Merge branch 'siw' into rdma.git for-next

Bernard Metzler says:

====================
This patch set contributes the SoftiWarp driver rebased for latest
rdma-next. SoftiWarp (siw) implements the iWarp RDMA protocol over kernel
TCP sockets. The driver integrates with the linux-rdma framework.

A matching userlevel driver is available as PR at
https://github.com/linux-rdma/rdma-core/pull/536

Many thanks for reviewing and testing the driver, especially to Leon,
Jason, Steve, Doug, Olga, Dennis, Gal. You all helped to significantly
improve the driver over the last year.

Please find below a list of changes and comments, compared to older
versions of the siw driver.

Many thanks!
Bernard.

CHANGES:
========

v3 (this version)
-----------------

- Rebased to rdma-next

- Removed unneccessary initialization of enums in siw-abi.h

- Added comment on sizing of all work queues to power of two.

v2
-----------------

- Changed recieve path CRC calculation to compute CRC32c not
  on target buffer after placement, but on original skbuf.
  This change severely hurts performance, if CRC is switched
  on, since skb must now be walked twice. It is planned to
  work on an extension to skb_copy_bits() to fold in CRC
  computation.

- Moved debugging to using ibdev_dbg().

- Dropped detailed packet debug printing.

- Removed siw_debug.[ch] files.

- Removed resource tracking, code now relies on restrack of
  RDMA midlayer. Only object counting to enforce reported
  device limits is left in place.

- Removed all nested switch-case statements.

- Cleaned up header file #include's

- Moved CQ create/destroy to new semantics,
  where midlayer creates/destroys containing object.

- Set siw's ABI version to 1 (was 0 before)

- Removed all enum initialization where not needed.

- Fixed MAINTANERS entry for siw driver

- This version stays with the current siw specific
  management of user memory (siw_umem_get() vs.
  ib_umem_get(), etc.). This, since the current ib_umem
  implementation is less efficient for user page lookup
  on the fast path, where effciency is important for a
  SW RDMA driver.
  It is planned to contribute enhancements to the ib_umem
  framework, wich makes it suitable for SW drivers as well.

v1 (first version after v9 of siw RFC)
--------------------------------------

- Rebased to 5.2-rc1

- All IDR code got removed.

- Both MR and QP deallocation verbs now synchronously
  free the resources referenced by the RDMA mid-layer.

- IPv6 support was added.

- For compatibility with Chelsio iWarp hardware, the RX
  path was slightly reworked. It now allows packet intersection
  between tagged and untagged RDMAP operations. While not
  a defined behavior as of IETF RFC 5040/5041, some RDMA hardware
  may intersect an ongoing outbound (large) tagged message, such
  as an multisegment RDMA Read Response with sending an untagged
  message, such as an RDMA Send frame. This behavior was only
  detected in an NVMeF setup, where siw was used at target side,
  and RDMA hardware at client side (during file write). siw now
  implements two input paths for tagged and untagged messages each,
  and allows the intersected placement of both messages.

- The siw kernel abi file got renamed from siw_user.h to siw-abi.h.
====================

* branch 'siw':
  SIW addition to kernel build environment
  SIW completion queue methods
  SIW receive path
  SIW transmit path
  SIW queue pair methods
  SIW application buffer management
  SIW application interface
  SIW connection management
  SIW network and RDMA core interface
  SIW main include file
  iWarp wire packet format

20 files changed, 10773 insertions, 0 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index 83a62b911692..6d2de0c1520e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -14558,6 +14558,13 @@ M:	Chris Boot <bootc@bootc.net>
 S:	Maintained
 F:	drivers/leds/leds-net48xx.c
 
+SOFT-IWARP DRIVER (siw)
+M:	Bernard Metzler <bmt@zurich.ibm.com>
+L:	linux-rdma@vger.kernel.org
+S:	Supported
+F:	drivers/infiniband/sw/siw/
+F:	include/uapi/rdma/siw-abi.h
+
 SOFT-ROCE DRIVER (rxe)
 M:	Moni Shoua <monis@mellanox.com>
 L:	linux-rdma@vger.kernel.org
diff --git a/drivers/infiniband/Kconfig b/drivers/infiniband/Kconfig
index 42af4cd40ba2..f277cb7aea29 100644
--- a/drivers/infiniband/Kconfig
+++ b/drivers/infiniband/Kconfig
@@ -96,6 +96,7 @@ source "drivers/infiniband/hw/hfi1/Kconfig"
 source "drivers/infiniband/hw/qedr/Kconfig"
 source "drivers/infiniband/sw/rdmavt/Kconfig"
 source "drivers/infiniband/sw/rxe/Kconfig"
+source "drivers/infiniband/sw/siw/Kconfig"
 endif
 
 source "drivers/infiniband/ulp/ipoib/Kconfig"
diff --git a/drivers/infiniband/sw/Makefile b/drivers/infiniband/sw/Makefile
index ab48a9b60844..68e0230f8f31 100644
--- a/drivers/infiniband/sw/Makefile
+++ b/drivers/infiniband/sw/Makefile
@@ -1,3 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0-only
 obj-$(CONFIG_INFINIBAND_RDMAVT)		+= rdmavt/
 obj-$(CONFIG_RDMA_RXE)			+= rxe/
+obj-$(CONFIG_RDMA_SIW)			+= siw/
diff --git a/drivers/infiniband/sw/siw/Kconfig b/drivers/infiniband/sw/siw/Kconfig
new file mode 100644
index 000000000000..94f684174ce3
--- /dev/null
+++ b/drivers/infiniband/sw/siw/Kconfig
@@ -0,0 +1,17 @@
+config RDMA_SIW
+	tristate "Software RDMA over TCP/IP (iWARP) driver"
+	depends on INET && INFINIBAND && CRYPTO_CRC32
+	help
+	This driver implements the iWARP RDMA transport over
+	the Linux TCP/IP network stack. It enables a system with a
+	standard Ethernet adapter to interoperate with a iWARP
+	adapter or with another system running the SIW driver.
+	(See also RXE which is a similar software driver for RoCE.)
+
+	The driver interfaces with the Linux RDMA stack and
+	implements both a kernel and user space RDMA verbs API.
+	The user space verbs API requires a support
+	library named libsiw which is loaded by the generic user
+	space verbs API, libibverbs. To implement RDMA over
+	TCP/IP, the driver further interfaces with the Linux
+	in-kernel TCP socket layer.
diff --git a/drivers/infiniband/sw/siw/Makefile b/drivers/infiniband/sw/siw/Makefile
new file mode 100644
index 000000000000..f5f7e3867889
--- /dev/null
+++ b/drivers/infiniband/sw/siw/Makefile
@@ -0,0 +1,11 @@
+obj-$(CONFIG_RDMA_SIW) += siw.o
+
+siw-y := \
+	siw_cm.o \
+	siw_cq.o \
+	siw_main.o \
+	siw_mem.o \
+	siw_qp.o \
+	siw_qp_tx.o \
+	siw_qp_rx.o \
+	siw_verbs.o
diff --git a/drivers/infiniband/sw/siw/iwarp.h b/drivers/infiniband/sw/siw/iwarp.h
new file mode 100644
index 000000000000..e8a04d9c89cb
--- /dev/null
+++ b/drivers/infiniband/sw/siw/iwarp.h
@@ -0,0 +1,380 @@
+/* SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause */
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+
+#ifndef _IWARP_H
+#define _IWARP_H
+
+#include <rdma/rdma_user_cm.h> /* RDMA_MAX_PRIVATE_DATA */
+#include <linux/types.h>
+#include <asm/byteorder.h>
+
+#define RDMAP_VERSION 1
+#define DDP_VERSION 1
+#define MPA_REVISION_1 1
+#define MPA_REVISION_2 2
+#define MPA_MAX_PRIVDATA RDMA_MAX_PRIVATE_DATA
+#define MPA_KEY_REQ "MPA ID Req Frame"
+#define MPA_KEY_REP "MPA ID Rep Frame"
+#define MPA_IRD_ORD_MASK 0x3fff
+
+struct mpa_rr_params {
+	__be16 bits;
+	__be16 pd_len;
+};
+
+/*
+ * MPA request/response header bits & fields
+ */
+enum {
+	MPA_RR_FLAG_MARKERS = cpu_to_be16(0x8000),
+	MPA_RR_FLAG_CRC = cpu_to_be16(0x4000),
+	MPA_RR_FLAG_REJECT = cpu_to_be16(0x2000),
+	MPA_RR_FLAG_ENHANCED = cpu_to_be16(0x1000),
+	MPA_RR_FLAG_GSO_EXP = cpu_to_be16(0x0800),
+	MPA_RR_MASK_REVISION = cpu_to_be16(0x00ff)
+};
+
+/*
+ * MPA request/reply header
+ */
+struct mpa_rr {
+	__u8 key[16];
+	struct mpa_rr_params params;
+};
+
+static inline void __mpa_rr_set_revision(__be16 *bits, u8 rev)
+{
+	*bits = (*bits & ~MPA_RR_MASK_REVISION) |
+		(cpu_to_be16(rev) & MPA_RR_MASK_REVISION);
+}
+
+static inline u8 __mpa_rr_revision(__be16 mpa_rr_bits)
+{
+	__be16 rev = mpa_rr_bits & MPA_RR_MASK_REVISION;
+
+	return be16_to_cpu(rev);
+}
+
+enum mpa_v2_ctrl {
+	MPA_V2_PEER_TO_PEER = cpu_to_be16(0x8000),
+	MPA_V2_ZERO_LENGTH_RTR = cpu_to_be16(0x4000),
+	MPA_V2_RDMA_WRITE_RTR = cpu_to_be16(0x8000),
+	MPA_V2_RDMA_READ_RTR = cpu_to_be16(0x4000),
+	MPA_V2_RDMA_NO_RTR = cpu_to_be16(0x0000),
+	MPA_V2_MASK_IRD_ORD = cpu_to_be16(0x3fff)
+};
+
+struct mpa_v2_data {
+	__be16 ird;
+	__be16 ord;
+};
+
+struct mpa_marker {
+	__be16 rsvd;
+	__be16 fpdu_hmd; /* FPDU header-marker distance (= MPA's FPDUPTR) */
+};
+
+/*
+ * maximum MPA trailer
+ */
+struct mpa_trailer {
+	__u8 pad[4];
+	__be32 crc;
+};
+
+#define MPA_HDR_SIZE 2
+#define MPA_CRC_SIZE 4
+
+/*
+ * Common portion of iWARP headers (MPA, DDP, RDMAP)
+ * for any FPDU
+ */
+struct iwarp_ctrl {
+	__be16 mpa_len;
+	__be16 ddp_rdmap_ctrl;
+};
+
+/*
+ * DDP/RDMAP Hdr bits & fields
+ */
+enum {
+	DDP_FLAG_TAGGED = cpu_to_be16(0x8000),
+	DDP_FLAG_LAST = cpu_to_be16(0x4000),
+	DDP_MASK_RESERVED = cpu_to_be16(0x3C00),
+	DDP_MASK_VERSION = cpu_to_be16(0x0300),
+	RDMAP_MASK_VERSION = cpu_to_be16(0x00C0),
+	RDMAP_MASK_RESERVED = cpu_to_be16(0x0030),
+	RDMAP_MASK_OPCODE = cpu_to_be16(0x000f)
+};
+
+static inline u8 __ddp_get_version(struct iwarp_ctrl *ctrl)
+{
+	return be16_to_cpu(ctrl->ddp_rdmap_ctrl & DDP_MASK_VERSION) >> 8;
+}
+
+static inline void __ddp_set_version(struct iwarp_ctrl *ctrl, u8 version)
+{
+	ctrl->ddp_rdmap_ctrl =
+		(ctrl->ddp_rdmap_ctrl & ~DDP_MASK_VERSION) |
+		(cpu_to_be16((u16)version << 8) & DDP_MASK_VERSION);
+}
+
+static inline u8 __rdmap_get_version(struct iwarp_ctrl *ctrl)
+{
+	__be16 ver = ctrl->ddp_rdmap_ctrl & RDMAP_MASK_VERSION;
+
+	return be16_to_cpu(ver) >> 6;
+}
+
+static inline void __rdmap_set_version(struct iwarp_ctrl *ctrl, u8 version)
+{
+	ctrl->ddp_rdmap_ctrl = (ctrl->ddp_rdmap_ctrl & ~RDMAP_MASK_VERSION) |
+			       (cpu_to_be16(version << 6) & RDMAP_MASK_VERSION);
+}
+
+static inline u8 __rdmap_get_opcode(struct iwarp_ctrl *ctrl)
+{
+	return be16_to_cpu(ctrl->ddp_rdmap_ctrl & RDMAP_MASK_OPCODE);
+}
+
+static inline void __rdmap_set_opcode(struct iwarp_ctrl *ctrl, u8 opcode)
+{
+	ctrl->ddp_rdmap_ctrl = (ctrl->ddp_rdmap_ctrl & ~RDMAP_MASK_OPCODE) |
+			       (cpu_to_be16(opcode) & RDMAP_MASK_OPCODE);
+}
+
+struct iwarp_rdma_write {
+	struct iwarp_ctrl ctrl;
+	__be32 sink_stag;
+	__be64 sink_to;
+};
+
+struct iwarp_rdma_rreq {
+	struct iwarp_ctrl ctrl;
+	__be32 rsvd;
+	__be32 ddp_qn;
+	__be32 ddp_msn;
+	__be32 ddp_mo;
+	__be32 sink_stag;
+	__be64 sink_to;
+	__be32 read_size;
+	__be32 source_stag;
+	__be64 source_to;
+};
+
+struct iwarp_rdma_rresp {
+	struct iwarp_ctrl ctrl;
+	__be32 sink_stag;
+	__be64 sink_to;
+};
+
+struct iwarp_send {
+	struct iwarp_ctrl ctrl;
+	__be32 rsvd;
+	__be32 ddp_qn;
+	__be32 ddp_msn;
+	__be32 ddp_mo;
+};
+
+struct iwarp_send_inv {
+	struct iwarp_ctrl ctrl;
+	__be32 inval_stag;
+	__be32 ddp_qn;
+	__be32 ddp_msn;
+	__be32 ddp_mo;
+};
+
+struct iwarp_terminate {
+	struct iwarp_ctrl ctrl;
+	__be32 rsvd;
+	__be32 ddp_qn;
+	__be32 ddp_msn;
+	__be32 ddp_mo;
+#if defined(__LITTLE_ENDIAN_BITFIELD)
+	__be32 layer : 4;
+	__be32 etype : 4;
+	__be32 ecode : 8;
+	__be32 flag_m : 1;
+	__be32 flag_d : 1;
+	__be32 flag_r : 1;
+	__be32 reserved : 13;
+#elif defined(__BIG_ENDIAN_BITFIELD)
+	__be32 reserved : 13;
+	__be32 flag_r : 1;
+	__be32 flag_d : 1;
+	__be32 flag_m : 1;
+	__be32 ecode : 8;
+	__be32 etype : 4;
+	__be32 layer : 4;
+#else
+#error "undefined byte order"
+#endif
+};
+
+/*
+ * Terminate Hdr bits & fields
+ */
+enum {
+	TERM_MASK_LAYER = cpu_to_be32(0xf0000000),
+	TERM_MASK_ETYPE = cpu_to_be32(0x0f000000),
+	TERM_MASK_ECODE = cpu_to_be32(0x00ff0000),
+	TERM_FLAG_M = cpu_to_be32(0x00008000),
+	TERM_FLAG_D = cpu_to_be32(0x00004000),
+	TERM_FLAG_R = cpu_to_be32(0x00002000),
+	TERM_MASK_RESVD = cpu_to_be32(0x00001fff)
+};
+
+static inline u8 __rdmap_term_layer(struct iwarp_terminate *term)
+{
+	return term->layer;
+}
+
+static inline void __rdmap_term_set_layer(struct iwarp_terminate *term,
+					  u8 layer)
+{
+	term->layer = layer & 0xf;
+}
+
+static inline u8 __rdmap_term_etype(struct iwarp_terminate *term)
+{
+	return term->etype;
+}
+
+static inline void __rdmap_term_set_etype(struct iwarp_terminate *term,
+					  u8 etype)
+{
+	term->etype = etype & 0xf;
+}
+
+static inline u8 __rdmap_term_ecode(struct iwarp_terminate *term)
+{
+	return term->ecode;
+}
+
+static inline void __rdmap_term_set_ecode(struct iwarp_terminate *term,
+					  u8 ecode)
+{
+	term->ecode = ecode;
+}
+
+/*
+ * Common portion of iWARP headers (MPA, DDP, RDMAP)
+ * for an FPDU carrying an untagged DDP segment
+ */
+struct iwarp_ctrl_untagged {
+	struct iwarp_ctrl ctrl;
+	__be32 rsvd;
+	__be32 ddp_qn;
+	__be32 ddp_msn;
+	__be32 ddp_mo;
+};
+
+/*
+ * Common portion of iWARP headers (MPA, DDP, RDMAP)
+ * for an FPDU carrying a tagged DDP segment
+ */
+struct iwarp_ctrl_tagged {
+	struct iwarp_ctrl ctrl;
+	__be32 ddp_stag;
+	__be64 ddp_to;
+};
+
+union iwarp_hdr {
+	struct iwarp_ctrl ctrl;
+	struct iwarp_ctrl_untagged c_untagged;
+	struct iwarp_ctrl_tagged c_tagged;
+	struct iwarp_rdma_write rwrite;
+	struct iwarp_rdma_rreq rreq;
+	struct iwarp_rdma_rresp rresp;
+	struct iwarp_terminate terminate;
+	struct iwarp_send send;
+	struct iwarp_send_inv send_inv;
+};
+
+enum term_elayer {
+	TERM_ERROR_LAYER_RDMAP = 0x00,
+	TERM_ERROR_LAYER_DDP = 0x01,
+	TERM_ERROR_LAYER_LLP = 0x02 /* eg., MPA */
+};
+
+enum ddp_etype {
+	DDP_ETYPE_CATASTROPHIC = 0x0,
+	DDP_ETYPE_TAGGED_BUF = 0x1,
+	DDP_ETYPE_UNTAGGED_BUF = 0x2,
+	DDP_ETYPE_RSVD = 0x3
+};
+
+enum ddp_ecode {
+	/* unspecified, set to zero */
+	DDP_ECODE_CATASTROPHIC = 0x00,
+	/* Tagged Buffer Errors */
+	DDP_ECODE_T_INVALID_STAG = 0x00,
+	DDP_ECODE_T_BASE_BOUNDS = 0x01,
+	DDP_ECODE_T_STAG_NOT_ASSOC = 0x02,
+	DDP_ECODE_T_TO_WRAP = 0x03,
+	DDP_ECODE_T_VERSION = 0x04,
+	/* Untagged Buffer Errors */
+	DDP_ECODE_UT_INVALID_QN = 0x01,
+	DDP_ECODE_UT_INVALID_MSN_NOBUF = 0x02,
+	DDP_ECODE_UT_INVALID_MSN_RANGE = 0x03,
+	DDP_ECODE_UT_INVALID_MO = 0x04,
+	DDP_ECODE_UT_MSG_TOOLONG = 0x05,
+	DDP_ECODE_UT_VERSION = 0x06
+};
+
+enum rdmap_untagged_qn {
+	RDMAP_UNTAGGED_QN_SEND = 0,
+	RDMAP_UNTAGGED_QN_RDMA_READ = 1,
+	RDMAP_UNTAGGED_QN_TERMINATE = 2,
+	RDMAP_UNTAGGED_QN_COUNT = 3
+};
+
+enum rdmap_etype {
+	RDMAP_ETYPE_CATASTROPHIC = 0x0,
+	RDMAP_ETYPE_REMOTE_PROTECTION = 0x1,
+	RDMAP_ETYPE_REMOTE_OPERATION = 0x2
+};
+
+enum rdmap_ecode {
+	RDMAP_ECODE_INVALID_STAG = 0x00,
+	RDMAP_ECODE_BASE_BOUNDS = 0x01,
+	RDMAP_ECODE_ACCESS_RIGHTS = 0x02,
+	RDMAP_ECODE_STAG_NOT_ASSOC = 0x03,
+	RDMAP_ECODE_TO_WRAP = 0x04,
+	RDMAP_ECODE_VERSION = 0x05,
+	RDMAP_ECODE_OPCODE = 0x06,
+	RDMAP_ECODE_CATASTROPHIC_STREAM = 0x07,
+	RDMAP_ECODE_CATASTROPHIC_GLOBAL = 0x08,
+	RDMAP_ECODE_CANNOT_INVALIDATE = 0x09,
+	RDMAP_ECODE_UNSPECIFIED = 0xff
+};
+
+enum llp_ecode {
+	LLP_ECODE_TCP_STREAM_LOST = 0x01, /* How to transfer this ?? */
+	LLP_ECODE_RECEIVED_CRC = 0x02,
+	LLP_ECODE_FPDU_START = 0x03,
+	LLP_ECODE_INVALID_REQ_RESP = 0x04,
+
+	/* Errors for Enhanced Connection Establishment only */
+	LLP_ECODE_LOCAL_CATASTROPHIC = 0x05,
+	LLP_ECODE_INSUFFICIENT_IRD = 0x06,
+	LLP_ECODE_NO_MATCHING_RTR = 0x07
+};
+
+enum llp_etype { LLP_ETYPE_MPA = 0x00 };
+
+enum rdma_opcode {
+	RDMAP_RDMA_WRITE = 0x0,
+	RDMAP_RDMA_READ_REQ = 0x1,
+	RDMAP_RDMA_READ_RESP = 0x2,
+	RDMAP_SEND = 0x3,
+	RDMAP_SEND_INVAL = 0x4,
+	RDMAP_SEND_SE = 0x5,
+	RDMAP_SEND_SE_INVAL = 0x6,
+	RDMAP_TERMINATE = 0x7,
+	RDMAP_NOT_SUPPORTED = RDMAP_TERMINATE + 1
+};
+
+#endif
diff --git a/drivers/infiniband/sw/siw/siw.h b/drivers/infiniband/sw/siw/siw.h
new file mode 100644
index 000000000000..03fd7b2f595f
--- /dev/null
+++ b/drivers/infiniband/sw/siw/siw.h
@@ -0,0 +1,745 @@
+/* SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause */
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+
+#ifndef _SIW_H
+#define _SIW_H
+
+#include <rdma/ib_verbs.h>
+#include <linux/socket.h>
+#include <linux/skbuff.h>
+#include <crypto/hash.h>
+#include <linux/crc32.h>
+#include <linux/crc32c.h>
+
+#include <rdma/siw-abi.h>
+#include "iwarp.h"
+
+#define SIW_VENDOR_ID 0x626d74 /* ascii 'bmt' for now */
+#define SIW_VENDORT_PART_ID 0
+#define SIW_MAX_QP (1024 * 100)
+#define SIW_MAX_QP_WR (1024 * 32)
+#define SIW_MAX_ORD_QP 128
+#define SIW_MAX_IRD_QP 128
+#define SIW_MAX_SGE_PBL 256 /* max num sge's for PBL */
+#define SIW_MAX_SGE_RD 1 /* iwarp limitation. we could relax */
+#define SIW_MAX_CQ (1024 * 100)
+#define SIW_MAX_CQE (SIW_MAX_QP_WR * 100)
+#define SIW_MAX_MR (SIW_MAX_QP * 10)
+#define SIW_MAX_PD SIW_MAX_QP
+#define SIW_MAX_MW 0 /* to be set if MW's are supported */
+#define SIW_MAX_FMR SIW_MAX_MR
+#define SIW_MAX_SRQ SIW_MAX_QP
+#define SIW_MAX_SRQ_WR (SIW_MAX_QP_WR * 10)
+#define SIW_MAX_CONTEXT SIW_MAX_PD
+
+/* Min number of bytes for using zero copy transmit */
+#define SENDPAGE_THRESH PAGE_SIZE
+
+/* Maximum number of frames which can be send in one SQ processing */
+#define SQ_USER_MAXBURST 100
+
+/* Maximum number of consecutive IRQ elements which get served
+ * if SQ has pending work. Prevents starving local SQ processing
+ * by serving peer Read Requests.
+ */
+#define SIW_IRQ_MAXBURST_SQ_ACTIVE 4
+
+struct siw_dev_cap {
+	int max_qp;
+	int max_qp_wr;
+	int max_ord; /* max. outbound read queue depth */
+	int max_ird; /* max. inbound read queue depth */
+	int max_sge;
+	int max_sge_rd;
+	int max_cq;
+	int max_cqe;
+	int max_mr;
+	int max_pd;
+	int max_mw;
+	int max_fmr;
+	int max_srq;
+	int max_srq_wr;
+	int max_srq_sge;
+};
+
+struct siw_pd {
+	struct ib_pd base_pd;
+};
+
+struct siw_device {
+	struct ib_device base_dev;
+	struct net_device *netdev;
+	struct siw_dev_cap attrs;
+
+	u32 vendor_part_id;
+	int numa_node;
+
+	/* physical port state (only one port per device) */
+	enum ib_port_state state;
+
+	spinlock_t lock;
+
+	struct xarray qp_xa;
+	struct xarray mem_xa;
+
+	struct list_head cep_list;
+	struct list_head qp_list;
+
+	/* active objects statistics to enforce limits */
+	atomic_t num_qp;
+	atomic_t num_cq;
+	atomic_t num_pd;
+	atomic_t num_mr;
+	atomic_t num_srq;
+	atomic_t num_ctx;
+
+	struct work_struct netdev_down;
+};
+
+struct siw_uobj {
+	void *addr;
+	u32 size;
+};
+
+struct siw_ucontext {
+	struct ib_ucontext base_ucontext;
+	struct siw_device *sdev;
+
+	/* xarray of user mappable objects */
+	struct xarray xa;
+	u32 uobj_nextkey;
+};
+
+/*
+ * The RDMA core does not define LOCAL_READ access, which is always
+ * enabled implictely.
+ */
+#define IWARP_ACCESS_MASK					\
+	(IB_ACCESS_LOCAL_WRITE | IB_ACCESS_REMOTE_WRITE	|	\
+	 IB_ACCESS_REMOTE_READ)
+
+/*
+ * siw presentation of user memory registered as source
+ * or target of RDMA operations.
+ */
+
+struct siw_page_chunk {
+	struct page **plist;
+};
+
+struct siw_umem {
+	struct siw_page_chunk *page_chunk;
+	int num_pages;
+	bool writable;
+	u64 fp_addr; /* First page base address */
+	struct mm_struct *owning_mm;
+};
+
+struct siw_pble {
+	u64 addr; /* Address of assigned user buffer */
+	u64 size; /* Size of this entry */
+	u64 pbl_off; /* Total offset from start of PBL */
+};
+
+struct siw_pbl {
+	unsigned int num_buf;
+	unsigned int max_buf;
+	struct siw_pble pbe[1];
+};
+
+struct siw_mr;
+
+/*
+ * Generic memory representation for registered siw memory.
+ * Memory lookup always via higher 24 bit of STag (STag index).
+ */
+struct siw_mem {
+	struct siw_device *sdev;
+	struct kref ref;
+	u64 va; /* VA of memory */
+	u64 len; /* length of the memory buffer in bytes */
+	u32 stag; /* iWarp memory access steering tag */
+	u8 stag_valid; /* VALID or INVALID */
+	u8 is_pbl; /* PBL or user space mem */
+	u8 is_mw; /* Memory Region or Memory Window */
+	enum ib_access_flags perms; /* local/remote READ & WRITE */
+	union {
+		struct siw_umem *umem;
+		struct siw_pbl *pbl;
+		void *mem_obj;
+	};
+	struct ib_pd *pd;
+};
+
+struct siw_mr {
+	struct ib_mr base_mr;
+	struct siw_mem *mem;
+	struct rcu_head rcu;
+};
+
+/*
+ * Error codes for local or remote
+ * access to registered memory
+ */
+enum siw_access_state {
+	E_ACCESS_OK,
+	E_STAG_INVALID,
+	E_BASE_BOUNDS,
+	E_ACCESS_PERM,
+	E_PD_MISMATCH
+};
+
+enum siw_wr_state {
+	SIW_WR_IDLE,
+	SIW_WR_QUEUED, /* processing has not started yet */
+	SIW_WR_INPROGRESS /* initiated processing of the WR */
+};
+
+/* The WQE currently being processed (RX or TX) */
+struct siw_wqe {
+	/* Copy of applications SQE or RQE */
+	union {
+		struct siw_sqe sqe;
+		struct siw_rqe rqe;
+	};
+	struct siw_mem *mem[SIW_MAX_SGE]; /* per sge's resolved mem */
+	enum siw_wr_state wr_status;
+	enum siw_wc_status wc_status;
+	u32 bytes; /* total bytes to process */
+	u32 processed; /* bytes processed */
+};
+
+struct siw_cq {
+	struct ib_cq base_cq;
+	spinlock_t lock;
+	u64 *notify;
+	struct siw_cqe *queue;
+	u32 cq_put;
+	u32 cq_get;
+	u32 num_cqe;
+	bool kernel_verbs;
+	u32 xa_cq_index; /* mmap information for CQE array */
+	u32 id; /* For debugging only */
+};
+
+enum siw_qp_state {
+	SIW_QP_STATE_IDLE,
+	SIW_QP_STATE_RTR,
+	SIW_QP_STATE_RTS,
+	SIW_QP_STATE_CLOSING,
+	SIW_QP_STATE_TERMINATE,
+	SIW_QP_STATE_ERROR,
+	SIW_QP_STATE_COUNT
+};
+
+enum siw_qp_flags {
+	SIW_RDMA_BIND_ENABLED = (1 << 0),
+	SIW_RDMA_WRITE_ENABLED = (1 << 1),
+	SIW_RDMA_READ_ENABLED = (1 << 2),
+	SIW_SIGNAL_ALL_WR = (1 << 3),
+	SIW_MPA_CRC = (1 << 4),
+	SIW_QP_IN_DESTROY = (1 << 5)
+};
+
+enum siw_qp_attr_mask {
+	SIW_QP_ATTR_STATE = (1 << 0),
+	SIW_QP_ATTR_ACCESS_FLAGS = (1 << 1),
+	SIW_QP_ATTR_LLP_HANDLE = (1 << 2),
+	SIW_QP_ATTR_ORD = (1 << 3),
+	SIW_QP_ATTR_IRD = (1 << 4),
+	SIW_QP_ATTR_SQ_SIZE = (1 << 5),
+	SIW_QP_ATTR_RQ_SIZE = (1 << 6),
+	SIW_QP_ATTR_MPA = (1 << 7)
+};
+
+struct siw_srq {
+	struct ib_srq base_srq;
+	spinlock_t lock;
+	u32 max_sge;
+	u32 limit; /* low watermark for async event */
+	struct siw_rqe *recvq;
+	u32 rq_put;
+	u32 rq_get;
+	u32 num_rqe; /* max # of wqe's allowed */
+	u32 xa_srq_index; /* mmap information for SRQ array */
+	char armed; /* inform user if limit hit */
+	char kernel_verbs; /* '1' if kernel client */
+};
+
+struct siw_qp_attrs {
+	enum siw_qp_state state;
+	u32 sq_size;
+	u32 rq_size;
+	u32 orq_size;
+	u32 irq_size;
+	u32 sq_max_sges;
+	u32 rq_max_sges;
+	enum siw_qp_flags flags;
+
+	struct socket *sk;
+};
+
+enum siw_tx_ctx {
+	SIW_SEND_HDR, /* start or continue sending HDR */
+	SIW_SEND_DATA, /* start or continue sending DDP payload */
+	SIW_SEND_TRAILER, /* start or continue sending TRAILER */
+	SIW_SEND_SHORT_FPDU/* send whole FPDU hdr|data|trailer at once */
+};
+
+enum siw_rx_state {
+	SIW_GET_HDR, /* await new hdr or within hdr */
+	SIW_GET_DATA_START, /* start of inbound DDP payload */
+	SIW_GET_DATA_MORE, /* continuation of (misaligned) DDP payload */
+	SIW_GET_TRAILER/* await new trailer or within trailer */
+};
+
+struct siw_rx_stream {
+	struct sk_buff *skb;
+	int skb_new; /* pending unread bytes in skb */
+	int skb_offset; /* offset in skb */
+	int skb_copied; /* processed bytes in skb */
+
+	union iwarp_hdr hdr;
+	struct mpa_trailer trailer;
+
+	enum siw_rx_state state;
+
+	/*
+	 * For each FPDU, main RX loop runs through 3 stages:
+	 * Receiving protocol headers, placing DDP payload and receiving
+	 * trailer information (CRC + possibly padding).
+	 * Next two variables keep state on receive status of the
+	 * current FPDU part (hdr, data, trailer).
+	 */
+	int fpdu_part_rcvd; /* bytes in pkt part copied */
+	int fpdu_part_rem; /* bytes in pkt part not seen */
+
+	/*
+	 * Next expected DDP MSN for each QN +
+	 * expected steering tag +
+	 * expected DDP tagget offset (all HBO)
+	 */
+	u32 ddp_msn[RDMAP_UNTAGGED_QN_COUNT];
+	u32 ddp_stag;
+	u64 ddp_to;
+	u32 inval_stag; /* Stag to be invalidated */
+
+	struct shash_desc *mpa_crc_hd;
+	u8 rx_suspend : 1;
+	u8 pad : 2; /* # of pad bytes expected */
+	u8 rdmap_op : 4; /* opcode of current frame */
+};
+
+struct siw_rx_fpdu {
+	/*
+	 * Local destination memory of inbound RDMA operation.
+	 * Valid, according to wqe->wr_status
+	 */
+	struct siw_wqe wqe_active;
+
+	unsigned int pbl_idx; /* Index into current PBL */
+	unsigned int sge_idx; /* current sge in rx */
+	unsigned int sge_off; /* already rcvd in curr. sge */
+
+	char first_ddp_seg; /* this is the first DDP seg */
+	char more_ddp_segs; /* more DDP segs expected */
+	u8 prev_rdmap_op : 4; /* opcode of prev frame */
+};
+
+/*
+ * Shorthands for short packets w/o payload
+ * to be transmitted more efficient.
+ */
+struct siw_send_pkt {
+	struct iwarp_send send;
+	__be32 crc;
+};
+
+struct siw_write_pkt {
+	struct iwarp_rdma_write write;
+	__be32 crc;
+};
+
+struct siw_rreq_pkt {
+	struct iwarp_rdma_rreq rreq;
+	__be32 crc;
+};
+
+struct siw_rresp_pkt {
+	struct iwarp_rdma_rresp rresp;
+	__be32 crc;
+};
+
+struct siw_iwarp_tx {
+	union {
+		union iwarp_hdr hdr;
+
+		/* Generic part of FPDU header */
+		struct iwarp_ctrl ctrl;
+		struct iwarp_ctrl_untagged c_untagged;
+		struct iwarp_ctrl_tagged c_tagged;
+
+		/* FPDU headers */
+		struct iwarp_rdma_write rwrite;
+		struct iwarp_rdma_rreq rreq;
+		struct iwarp_rdma_rresp rresp;
+		struct iwarp_terminate terminate;
+		struct iwarp_send send;
+		struct iwarp_send_inv send_inv;
+
+		/* complete short FPDUs */
+		struct siw_send_pkt send_pkt;
+		struct siw_write_pkt write_pkt;
+		struct siw_rreq_pkt rreq_pkt;
+		struct siw_rresp_pkt rresp_pkt;
+	} pkt;
+
+	struct mpa_trailer trailer;
+	/* DDP MSN for untagged messages */
+	u32 ddp_msn[RDMAP_UNTAGGED_QN_COUNT];
+
+	enum siw_tx_ctx state;
+	u16 ctrl_len; /* ddp+rdmap hdr */
+	u16 ctrl_sent;
+	int burst;
+	int bytes_unsent; /* ddp payload bytes */
+
+	struct shash_desc *mpa_crc_hd;
+
+	u8 do_crc : 1; /* do crc for segment */
+	u8 use_sendpage : 1; /* send w/o copy */
+	u8 tx_suspend : 1; /* stop sending DDP segs. */
+	u8 pad : 2; /* # pad in current fpdu */
+	u8 orq_fence : 1; /* ORQ full or Send fenced */
+	u8 in_syscall : 1; /* TX out of user context */
+	u8 zcopy_tx : 1; /* Use TCP_SENDPAGE if possible */
+	u8 gso_seg_limit; /* Maximum segments for GSO, 0 = unbound */
+
+	u16 fpdu_len; /* len of FPDU to tx */
+	unsigned int tcp_seglen; /* remaining tcp seg space */
+
+	struct siw_wqe wqe_active;
+
+	int pbl_idx; /* Index into current PBL */
+	int sge_idx; /* current sge in tx */
+	u32 sge_off; /* already sent in curr. sge */
+};
+
+struct siw_qp {
+	struct siw_device *sdev;
+	struct ib_qp *ib_qp;
+	struct kref ref;
+	u32 qp_num;
+	struct list_head devq;
+	int tx_cpu;
+	bool kernel_verbs;
+	struct siw_qp_attrs attrs;
+
+	struct siw_cep *cep;
+	struct rw_semaphore state_lock;
+
+	struct ib_pd *pd;
+	struct siw_cq *scq;
+	struct siw_cq *rcq;
+	struct siw_srq *srq;
+
+	struct siw_iwarp_tx tx_ctx; /* Transmit context */
+	spinlock_t sq_lock;
+	struct siw_sqe *sendq; /* send queue element array */
+	uint32_t sq_get; /* consumer index into sq array */
+	uint32_t sq_put; /* kernel prod. index into sq array */
+	struct llist_node tx_list;
+
+	struct siw_sqe *orq; /* outbound read queue element array */
+	spinlock_t orq_lock;
+	uint32_t orq_get; /* consumer index into orq array */
+	uint32_t orq_put; /* shared producer index for ORQ */
+
+	struct siw_rx_stream rx_stream;
+	struct siw_rx_fpdu *rx_fpdu;
+	struct siw_rx_fpdu rx_tagged;
+	struct siw_rx_fpdu rx_untagged;
+	spinlock_t rq_lock;
+	struct siw_rqe *recvq; /* recv queue element array */
+	uint32_t rq_get; /* consumer index into rq array */
+	uint32_t rq_put; /* kernel prod. index into rq array */
+
+	struct siw_sqe *irq; /* inbound read queue element array */
+	uint32_t irq_get; /* consumer index into irq array */
+	uint32_t irq_put; /* producer index into irq array */
+	int irq_burst;
+
+	struct { /* information to be carried in TERMINATE pkt, if valid */
+		u8 valid;
+		u8 in_tx;
+		u8 layer : 4, etype : 4;
+		u8 ecode;
+	} term_info;
+	u32 xa_sq_index; /* mmap information for SQE array */
+	u32 xa_rq_index; /* mmap information for RQE array */
+	struct rcu_head rcu;
+};
+
+struct siw_base_qp {
+	struct ib_qp base_qp;
+	struct siw_qp *qp;
+};
+
+/* helper macros */
+#define rx_qp(rx) container_of(rx, struct siw_qp, rx_stream)
+#define tx_qp(tx) container_of(tx, struct siw_qp, tx_ctx)
+#define tx_wqe(qp) (&(qp)->tx_ctx.wqe_active)
+#define rx_wqe(rctx) (&(rctx)->wqe_active)
+#define rx_mem(rctx) ((rctx)->wqe_active.mem[0])
+#define tx_type(wqe) ((wqe)->sqe.opcode)
+#define rx_type(wqe) ((wqe)->rqe.opcode)
+#define tx_flags(wqe) ((wqe)->sqe.flags)
+
+struct iwarp_msg_info {
+	int hdr_len;
+	struct iwarp_ctrl ctrl;
+	int (*rx_data)(struct siw_qp *qp);
+};
+
+/* Global siw parameters. Currently set in siw_main.c */
+extern const bool zcopy_tx;
+extern const bool try_gso;
+extern const bool loopback_enabled;
+extern const bool mpa_crc_required;
+extern const bool mpa_crc_strict;
+extern const bool siw_tcp_nagle;
+extern u_char mpa_version;
+extern const bool peer_to_peer;
+extern struct task_struct *siw_tx_thread[];
+
+extern struct crypto_shash *siw_crypto_shash;
+extern struct iwarp_msg_info iwarp_pktinfo[RDMAP_TERMINATE + 1];
+
+/* QP general functions */
+int siw_qp_modify(struct siw_qp *qp, struct siw_qp_attrs *attr,
+		  enum siw_qp_attr_mask mask);
+int siw_qp_mpa_rts(struct siw_qp *qp, enum mpa_v2_ctrl ctrl);
+void siw_qp_llp_close(struct siw_qp *qp);
+void siw_qp_cm_drop(struct siw_qp *qp, int schedule);
+void siw_send_terminate(struct siw_qp *qp);
+
+void siw_qp_get_ref(struct ib_qp *qp);
+void siw_qp_put_ref(struct ib_qp *qp);
+int siw_qp_add(struct siw_device *sdev, struct siw_qp *qp);
+void siw_free_qp(struct kref *ref);
+
+void siw_init_terminate(struct siw_qp *qp, enum term_elayer layer,
+			u8 etype, u8 ecode, int in_tx);
+enum ddp_ecode siw_tagged_error(enum siw_access_state state);
+enum rdmap_ecode siw_rdmap_error(enum siw_access_state state);
+
+void siw_read_to_orq(struct siw_sqe *rreq, struct siw_sqe *sqe);
+int siw_sqe_complete(struct siw_qp *qp, struct siw_sqe *sqe, u32 bytes,
+		     enum siw_wc_status status);
+int siw_rqe_complete(struct siw_qp *qp, struct siw_rqe *rqe, u32 bytes,
+		     u32 inval_stag, enum siw_wc_status status);
+void siw_qp_llp_data_ready(struct sock *sk);
+void siw_qp_llp_write_space(struct sock *sk);
+
+/* QP TX path functions */
+int siw_run_sq(void *arg);
+int siw_qp_sq_process(struct siw_qp *qp);
+int siw_sq_start(struct siw_qp *qp);
+int siw_activate_tx(struct siw_qp *qp);
+void siw_stop_tx_thread(int nr_cpu);
+int siw_get_tx_cpu(struct siw_device *sdev);
+void siw_put_tx_cpu(int cpu);
+
+/* QP RX path functions */
+int siw_proc_send(struct siw_qp *qp);
+int siw_proc_rreq(struct siw_qp *qp);
+int siw_proc_rresp(struct siw_qp *qp);
+int siw_proc_write(struct siw_qp *qp);
+int siw_proc_terminate(struct siw_qp *qp);
+
+int siw_tcp_rx_data(read_descriptor_t *rd_desc, struct sk_buff *skb,
+		    unsigned int off, size_t len);
+
+static inline void set_rx_fpdu_context(struct siw_qp *qp, u8 opcode)
+{
+	if (opcode == RDMAP_RDMA_WRITE || opcode == RDMAP_RDMA_READ_RESP)
+		qp->rx_fpdu = &qp->rx_tagged;
+	else
+		qp->rx_fpdu = &qp->rx_untagged;
+
+	qp->rx_stream.rdmap_op = opcode;
+}
+
+static inline struct siw_ucontext *to_siw_ctx(struct ib_ucontext *base_ctx)
+{
+	return container_of(base_ctx, struct siw_ucontext, base_ucontext);
+}
+
+static inline struct siw_base_qp *to_siw_base_qp(struct ib_qp *base_qp)
+{
+	return container_of(base_qp, struct siw_base_qp, base_qp);
+}
+
+static inline struct siw_qp *to_siw_qp(struct ib_qp *base_qp)
+{
+	return to_siw_base_qp(base_qp)->qp;
+}
+
+static inline struct siw_cq *to_siw_cq(struct ib_cq *base_cq)
+{
+	return container_of(base_cq, struct siw_cq, base_cq);
+}
+
+static inline struct siw_srq *to_siw_srq(struct ib_srq *base_srq)
+{
+	return container_of(base_srq, struct siw_srq, base_srq);
+}
+
+static inline struct siw_device *to_siw_dev(struct ib_device *base_dev)
+{
+	return container_of(base_dev, struct siw_device, base_dev);
+}
+
+static inline struct siw_mr *to_siw_mr(struct ib_mr *base_mr)
+{
+	return container_of(base_mr, struct siw_mr, base_mr);
+}
+
+static inline struct siw_qp *siw_qp_id2obj(struct siw_device *sdev, int id)
+{
+	struct siw_qp *qp;
+
+	rcu_read_lock();
+	qp = xa_load(&sdev->qp_xa, id);
+	if (likely(qp && kref_get_unless_zero(&qp->ref))) {
+		rcu_read_unlock();
+		return qp;
+	}
+	rcu_read_unlock();
+	return NULL;
+}
+
+static inline u32 qp_id(struct siw_qp *qp)
+{
+	return qp->qp_num;
+}
+
+static inline void siw_qp_get(struct siw_qp *qp)
+{
+	kref_get(&qp->ref);
+}
+
+static inline void siw_qp_put(struct siw_qp *qp)
+{
+	kref_put(&qp->ref, siw_free_qp);
+}
+
+static inline int siw_sq_empty(struct siw_qp *qp)
+{
+	struct siw_sqe *sqe = &qp->sendq[qp->sq_get % qp->attrs.sq_size];
+
+	return READ_ONCE(sqe->flags) == 0;
+}
+
+static inline struct siw_sqe *sq_get_next(struct siw_qp *qp)
+{
+	struct siw_sqe *sqe = &qp->sendq[qp->sq_get % qp->attrs.sq_size];
+
+	if (READ_ONCE(sqe->flags) & SIW_WQE_VALID)
+		return sqe;
+
+	return NULL;
+}
+
+static inline struct siw_sqe *orq_get_current(struct siw_qp *qp)
+{
+	return &qp->orq[qp->orq_get % qp->attrs.orq_size];
+}
+
+static inline struct siw_sqe *orq_get_tail(struct siw_qp *qp)
+{
+	return &qp->orq[qp->orq_put % qp->attrs.orq_size];
+}
+
+static inline struct siw_sqe *orq_get_free(struct siw_qp *qp)
+{
+	struct siw_sqe *orq_e = orq_get_tail(qp);
+
+	if (orq_e && READ_ONCE(orq_e->flags) == 0)
+		return orq_e;
+
+	return NULL;
+}
+
+static inline int siw_orq_empty(struct siw_qp *qp)
+{
+	return qp->orq[qp->orq_get % qp->attrs.orq_size].flags == 0 ? 1 : 0;
+}
+
+static inline struct siw_sqe *irq_alloc_free(struct siw_qp *qp)
+{
+	struct siw_sqe *irq_e = &qp->irq[qp->irq_put % qp->attrs.irq_size];
+
+	if (READ_ONCE(irq_e->flags) == 0) {
+		qp->irq_put++;
+		return irq_e;
+	}
+	return NULL;
+}
+
+static inline __wsum siw_csum_update(const void *buff, int len, __wsum sum)
+{
+	return (__force __wsum)crc32c((__force __u32)sum, buff, len);
+}
+
+static inline __wsum siw_csum_combine(__wsum csum, __wsum csum2, int offset,
+				      int len)
+{
+	return (__force __wsum)__crc32c_le_combine((__force __u32)csum,
+						   (__force __u32)csum2, len);
+}
+
+static inline void siw_crc_skb(struct siw_rx_stream *srx, unsigned int len)
+{
+	const struct skb_checksum_ops siw_cs_ops = {
+		.update = siw_csum_update,
+		.combine = siw_csum_combine,
+	};
+	__wsum crc = *(u32 *)shash_desc_ctx(srx->mpa_crc_hd);
+
+	crc = __skb_checksum(srx->skb, srx->skb_offset, len, crc,
+			     &siw_cs_ops);
+	*(u32 *)shash_desc_ctx(srx->mpa_crc_hd) = crc;
+}
+
+#define siw_dbg(ibdev, fmt, ...)                                               \
+	ibdev_dbg(ibdev, "%s: " fmt, __func__, ##__VA_ARGS__)
+
+#define siw_dbg_qp(qp, fmt, ...)                                               \
+	ibdev_dbg(&qp->sdev->base_dev, "QP[%u] %s: " fmt, qp_id(qp), __func__, \
+		  ##__VA_ARGS__)
+
+#define siw_dbg_cq(cq, fmt, ...)                                               \
+	ibdev_dbg(cq->base_cq.device, "CQ[%u] %s: " fmt, cq->id, __func__,     \
+		  ##__VA_ARGS__)
+
+#define siw_dbg_pd(pd, fmt, ...)                                               \
+	ibdev_dbg(pd->device, "PD[%u] %s: " fmt, pd->res.id, __func__,         \
+		  ##__VA_ARGS__)
+
+#define siw_dbg_mem(mem, fmt, ...)                                             \
+	ibdev_dbg(&mem->sdev->base_dev,                                        \
+		  "MEM[0x%08x] %s: " fmt, mem->stag, __func__, ##__VA_ARGS__)
+
+#define siw_dbg_cep(cep, fmt, ...)                                             \
+	ibdev_dbg(&cep->sdev->base_dev, "CEP[0x%p] %s: " fmt,                  \
+		  cep, __func__, ##__VA_ARGS__)
+
+void siw_cq_flush(struct siw_cq *cq);
+void siw_sq_flush(struct siw_qp *qp);
+void siw_rq_flush(struct siw_qp *qp);
+int siw_reap_cqe(struct siw_cq *cq, struct ib_wc *wc);
+
+#endif
diff --git a/drivers/infiniband/sw/siw/siw_cm.c b/drivers/infiniband/sw/siw/siw_cm.c
new file mode 100644
index 000000000000..8e618cb7261f
--- /dev/null
+++ b/drivers/infiniband/sw/siw/siw_cm.c
@@ -0,0 +1,2072 @@
+// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/*          Fredy Neeser */
+/*          Greg Joyce <greg@opengridcomputing.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+/* Copyright (c) 2017, Open Grid Computing, Inc. */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/net.h>
+#include <linux/inetdevice.h>
+#include <net/addrconf.h>
+#include <linux/workqueue.h>
+#include <net/sock.h>
+#include <net/tcp.h>
+#include <linux/inet.h>
+#include <linux/tcp.h>
+
+#include <rdma/iw_cm.h>
+#include <rdma/ib_verbs.h>
+#include <rdma/ib_user_verbs.h>
+
+#include "siw.h"
+#include "siw_cm.h"
+
+/*
+ * Set to any combination of
+ * MPA_V2_RDMA_NO_RTR, MPA_V2_RDMA_READ_RTR, MPA_V2_RDMA_WRITE_RTR
+ */
+static __be16 rtr_type = MPA_V2_RDMA_READ_RTR | MPA_V2_RDMA_WRITE_RTR;
+static const bool relaxed_ird_negotiation = 1;
+
+static void siw_cm_llp_state_change(struct sock *s);
+static void siw_cm_llp_data_ready(struct sock *s);
+static void siw_cm_llp_write_space(struct sock *s);
+static void siw_cm_llp_error_report(struct sock *s);
+static int siw_cm_upcall(struct siw_cep *cep, enum iw_cm_event_type reason,
+			 int status);
+
+static void siw_sk_assign_cm_upcalls(struct sock *sk)
+{
+	write_lock_bh(&sk->sk_callback_lock);
+	sk->sk_state_change = siw_cm_llp_state_change;
+	sk->sk_data_ready = siw_cm_llp_data_ready;
+	sk->sk_write_space = siw_cm_llp_write_space;
+	sk->sk_error_report = siw_cm_llp_error_report;
+	write_unlock_bh(&sk->sk_callback_lock);
+}
+
+static void siw_sk_save_upcalls(struct sock *sk)
+{
+	struct siw_cep *cep = sk_to_cep(sk);
+
+	write_lock_bh(&sk->sk_callback_lock);
+	cep->sk_state_change = sk->sk_state_change;
+	cep->sk_data_ready = sk->sk_data_ready;
+	cep->sk_write_space = sk->sk_write_space;
+	cep->sk_error_report = sk->sk_error_report;
+	write_unlock_bh(&sk->sk_callback_lock);
+}
+
+static void siw_sk_restore_upcalls(struct sock *sk, struct siw_cep *cep)
+{
+	sk->sk_state_change = cep->sk_state_change;
+	sk->sk_data_ready = cep->sk_data_ready;
+	sk->sk_write_space = cep->sk_write_space;
+	sk->sk_error_report = cep->sk_error_report;
+	sk->sk_user_data = NULL;
+}
+
+static void siw_qp_socket_assoc(struct siw_cep *cep, struct siw_qp *qp)
+{
+	struct socket *s = cep->sock;
+	struct sock *sk = s->sk;
+
+	write_lock_bh(&sk->sk_callback_lock);
+
+	qp->attrs.sk = s;
+	sk->sk_data_ready = siw_qp_llp_data_ready;
+	sk->sk_write_space = siw_qp_llp_write_space;
+
+	write_unlock_bh(&sk->sk_callback_lock);
+}
+
+static void siw_socket_disassoc(struct socket *s)
+{
+	struct sock *sk = s->sk;
+	struct siw_cep *cep;
+
+	if (sk) {
+		write_lock_bh(&sk->sk_callback_lock);
+		cep = sk_to_cep(sk);
+		if (cep) {
+			siw_sk_restore_upcalls(sk, cep);
+			siw_cep_put(cep);
+		} else {
+			pr_warn("siw: cannot restore sk callbacks: no ep\n");
+		}
+		write_unlock_bh(&sk->sk_callback_lock);
+	} else {
+		pr_warn("siw: cannot restore sk callbacks: no sk\n");
+	}
+}
+
+static void siw_rtr_data_ready(struct sock *sk)
+{
+	struct siw_cep *cep;
+	struct siw_qp *qp = NULL;
+	read_descriptor_t rd_desc;
+
+	read_lock(&sk->sk_callback_lock);
+
+	cep = sk_to_cep(sk);
+	if (!cep) {
+		WARN(1, "No connection endpoint\n");
+		goto out;
+	}
+	qp = sk_to_qp(sk);
+
+	memset(&rd_desc, 0, sizeof(rd_desc));
+	rd_desc.arg.data = qp;
+	rd_desc.count = 1;
+
+	tcp_read_sock(sk, &rd_desc, siw_tcp_rx_data);
+	/*
+	 * Check if first frame was successfully processed.
+	 * Signal connection full establishment if yes.
+	 * Failed data processing would have already scheduled
+	 * connection drop.
+	 */
+	if (!qp->rx_stream.rx_suspend)
+		siw_cm_upcall(cep, IW_CM_EVENT_ESTABLISHED, 0);
+out:
+	read_unlock(&sk->sk_callback_lock);
+	if (qp)
+		siw_qp_socket_assoc(cep, qp);
+}
+
+static void siw_sk_assign_rtr_upcalls(struct siw_cep *cep)
+{
+	struct sock *sk = cep->sock->sk;
+
+	write_lock_bh(&sk->sk_callback_lock);
+	sk->sk_data_ready = siw_rtr_data_ready;
+	sk->sk_write_space = siw_qp_llp_write_space;
+	write_unlock_bh(&sk->sk_callback_lock);
+}
+
+static void siw_cep_socket_assoc(struct siw_cep *cep, struct socket *s)
+{
+	cep->sock = s;
+	siw_cep_get(cep);
+	s->sk->sk_user_data = cep;
+
+	siw_sk_save_upcalls(s->sk);
+	siw_sk_assign_cm_upcalls(s->sk);
+}
+
+static struct siw_cep *siw_cep_alloc(struct siw_device *sdev)
+{
+	struct siw_cep *cep = kzalloc(sizeof(*cep), GFP_KERNEL);
+	unsigned long flags;
+
+	if (!cep)
+		return NULL;
+
+	INIT_LIST_HEAD(&cep->listenq);
+	INIT_LIST_HEAD(&cep->devq);
+	INIT_LIST_HEAD(&cep->work_freelist);
+
+	kref_init(&cep->ref);
+	cep->state = SIW_EPSTATE_IDLE;
+	init_waitqueue_head(&cep->waitq);
+	spin_lock_init(&cep->lock);
+	cep->sdev = sdev;
+	cep->enhanced_rdma_conn_est = false;
+
+	spin_lock_irqsave(&sdev->lock, flags);
+	list_add_tail(&cep->devq, &sdev->cep_list);
+	spin_unlock_irqrestore(&sdev->lock, flags);
+
+	siw_dbg_cep(cep, "new endpoint\n");
+	return cep;
+}
+
+static void siw_cm_free_work(struct siw_cep *cep)
+{
+	struct list_head *w, *tmp;
+	struct siw_cm_work *work;
+
+	list_for_each_safe(w, tmp, &cep->work_freelist) {
+		work = list_entry(w, struct siw_cm_work, list);
+		list_del(&work->list);
+		kfree(work);
+	}
+}
+
+static void siw_cancel_mpatimer(struct siw_cep *cep)
+{
+	spin_lock_bh(&cep->lock);
+	if (cep->mpa_timer) {
+		if (cancel_delayed_work(&cep->mpa_timer->work)) {
+			siw_cep_put(cep);
+			kfree(cep->mpa_timer); /* not needed again */
+		}
+		cep->mpa_timer = NULL;
+	}
+	spin_unlock_bh(&cep->lock);
+}
+
+static void siw_put_work(struct siw_cm_work *work)
+{
+	INIT_LIST_HEAD(&work->list);
+	spin_lock_bh(&work->cep->lock);
+	list_add(&work->list, &work->cep->work_freelist);
+	spin_unlock_bh(&work->cep->lock);
+}
+
+static void siw_cep_set_inuse(struct siw_cep *cep)
+{
+	unsigned long flags;
+	int rv;
+retry:
+	spin_lock_irqsave(&cep->lock, flags);
+
+	if (cep->in_use) {
+		spin_unlock_irqrestore(&cep->lock, flags);
+		rv = wait_event_interruptible(cep->waitq, !cep->in_use);
+		if (signal_pending(current))
+			flush_signals(current);
+		goto retry;
+	} else {
+		cep->in_use = 1;
+		spin_unlock_irqrestore(&cep->lock, flags);
+	}
+}
+
+static void siw_cep_set_free(struct siw_cep *cep)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&cep->lock, flags);
+	cep->in_use = 0;
+	spin_unlock_irqrestore(&cep->lock, flags);
+
+	wake_up(&cep->waitq);
+}
+
+static void __siw_cep_dealloc(struct kref *ref)
+{
+	struct siw_cep *cep = container_of(ref, struct siw_cep, ref);
+	struct siw_device *sdev = cep->sdev;
+	unsigned long flags;
+
+	WARN_ON(cep->listen_cep);
+
+	/* kfree(NULL) is safe */
+	kfree(cep->mpa.pdata);
+	spin_lock_bh(&cep->lock);
+	if (!list_empty(&cep->work_freelist))
+		siw_cm_free_work(cep);
+	spin_unlock_bh(&cep->lock);
+
+	spin_lock_irqsave(&sdev->lock, flags);
+	list_del(&cep->devq);
+	spin_unlock_irqrestore(&sdev->lock, flags);
+
+	siw_dbg_cep(cep, "free endpoint\n");
+	kfree(cep);
+}
+
+static struct siw_cm_work *siw_get_work(struct siw_cep *cep)
+{
+	struct siw_cm_work *work = NULL;
+
+	spin_lock_bh(&cep->lock);
+	if (!list_empty(&cep->work_freelist)) {
+		work = list_entry(cep->work_freelist.next, struct siw_cm_work,
+				  list);
+		list_del_init(&work->list);
+	}
+	spin_unlock_bh(&cep->lock);
+	return work;
+}
+
+static int siw_cm_alloc_work(struct siw_cep *cep, int num)
+{
+	struct siw_cm_work *work;
+
+	while (num--) {
+		work = kmalloc(sizeof(*work), GFP_KERNEL);
+		if (!work) {
+			if (!(list_empty(&cep->work_freelist)))
+				siw_cm_free_work(cep);
+			return -ENOMEM;
+		}
+		work->cep = cep;
+		INIT_LIST_HEAD(&work->list);
+		list_add(&work->list, &cep->work_freelist);
+	}
+	return 0;
+}
+
+/*
+ * siw_cm_upcall()
+ *
+ * Upcall to IWCM to inform about async connection events
+ */
+static int siw_cm_upcall(struct siw_cep *cep, enum iw_cm_event_type reason,
+			 int status)
+{
+	struct iw_cm_event event;
+	struct iw_cm_id *id;
+
+	memset(&event, 0, sizeof(event));
+	event.status = status;
+	event.event = reason;
+
+	if (reason == IW_CM_EVENT_CONNECT_REQUEST) {
+		event.provider_data = cep;
+		id = cep->listen_cep->cm_id;
+	} else {
+		id = cep->cm_id;
+	}
+	/* Signal IRD and ORD */
+	if (reason == IW_CM_EVENT_ESTABLISHED ||
+	    reason == IW_CM_EVENT_CONNECT_REPLY) {
+		/* Signal negotiated IRD/ORD values we will use */
+		event.ird = cep->ird;
+		event.ord = cep->ord;
+	} else if (reason == IW_CM_EVENT_CONNECT_REQUEST) {
+		event.ird = cep->ord;
+		event.ord = cep->ird;
+	}
+	/* Signal private data and address information */
+	if (reason == IW_CM_EVENT_CONNECT_REQUEST ||
+	    reason == IW_CM_EVENT_CONNECT_REPLY) {
+		u16 pd_len = be16_to_cpu(cep->mpa.hdr.params.pd_len);
+
+		if (pd_len) {
+			/*
+			 * hand over MPA private data
+			 */
+			event.private_data_len = pd_len;
+			event.private_data = cep->mpa.pdata;
+
+			/* Hide MPA V2 IRD/ORD control */
+			if (cep->enhanced_rdma_conn_est) {
+				event.private_data_len -=
+					sizeof(struct mpa_v2_data);
+				event.private_data +=
+					sizeof(struct mpa_v2_data);
+			}
+		}
+		getname_local(cep->sock, &event.local_addr);
+		getname_peer(cep->sock, &event.remote_addr);
+	}
+	siw_dbg_cep(cep, "[QP %u]: id 0x%p, reason=%d, status=%d\n",
+		    cep->qp ? qp_id(cep->qp) : -1, id, reason, status);
+
+	return id->event_handler(id, &event);
+}
+
+/*
+ * siw_qp_cm_drop()
+ *
+ * Drops established LLP connection if present and not already
+ * scheduled for dropping. Called from user context, SQ workqueue
+ * or receive IRQ. Caller signals if socket can be immediately
+ * closed (basically, if not in IRQ).
+ */
+void siw_qp_cm_drop(struct siw_qp *qp, int schedule)
+{
+	struct siw_cep *cep = qp->cep;
+
+	qp->rx_stream.rx_suspend = 1;
+	qp->tx_ctx.tx_suspend = 1;
+
+	if (!qp->cep)
+		return;
+
+	if (schedule) {
+		siw_cm_queue_work(cep, SIW_CM_WORK_CLOSE_LLP);
+	} else {
+		siw_cep_set_inuse(cep);
+
+		if (cep->state == SIW_EPSTATE_CLOSED) {
+			siw_dbg_cep(cep, "already closed\n");
+			goto out;
+		}
+		siw_dbg_cep(cep, "immediate close, state %d\n", cep->state);
+
+		if (qp->term_info.valid)
+			siw_send_terminate(qp);
+
+		if (cep->cm_id) {
+			switch (cep->state) {
+			case SIW_EPSTATE_AWAIT_MPAREP:
+				siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REPLY,
+					      -EINVAL);
+				break;
+
+			case SIW_EPSTATE_RDMA_MODE:
+				siw_cm_upcall(cep, IW_CM_EVENT_CLOSE, 0);
+				break;
+
+			case SIW_EPSTATE_IDLE:
+			case SIW_EPSTATE_LISTENING:
+			case SIW_EPSTATE_CONNECTING:
+			case SIW_EPSTATE_AWAIT_MPAREQ:
+			case SIW_EPSTATE_RECVD_MPAREQ:
+			case SIW_EPSTATE_CLOSED:
+			default:
+				break;
+			}
+			cep->cm_id->rem_ref(cep->cm_id);
+			cep->cm_id = NULL;
+			siw_cep_put(cep);
+		}
+		cep->state = SIW_EPSTATE_CLOSED;
+
+		if (cep->sock) {
+			siw_socket_disassoc(cep->sock);
+			/*
+			 * Immediately close socket
+			 */
+			sock_release(cep->sock);
+			cep->sock = NULL;
+		}
+		if (cep->qp) {
+			cep->qp = NULL;
+			siw_qp_put(qp);
+		}
+out:
+		siw_cep_set_free(cep);
+	}
+}
+
+void siw_cep_put(struct siw_cep *cep)
+{
+	WARN_ON(kref_read(&cep->ref) < 1);
+	kref_put(&cep->ref, __siw_cep_dealloc);
+}
+
+void siw_cep_get(struct siw_cep *cep)
+{
+	kref_get(&cep->ref);
+}
+
+/*
+ * Expects params->pd_len in host byte order
+ */
+static int siw_send_mpareqrep(struct siw_cep *cep, const void *pdata, u8 pd_len)
+{
+	struct socket *s = cep->sock;
+	struct mpa_rr *rr = &cep->mpa.hdr;
+	struct kvec iov[3];
+	struct msghdr msg;
+	int rv;
+	int iovec_num = 0;
+	int mpa_len;
+
+	memset(&msg, 0, sizeof(msg));
+
+	iov[iovec_num].iov_base = rr;
+	iov[iovec_num].iov_len = sizeof(*rr);
+	mpa_len = sizeof(*rr);
+
+	if (cep->enhanced_rdma_conn_est) {
+		iovec_num++;
+		iov[iovec_num].iov_base = &cep->mpa.v2_ctrl;
+		iov[iovec_num].iov_len = sizeof(cep->mpa.v2_ctrl);
+		mpa_len += sizeof(cep->mpa.v2_ctrl);
+	}
+	if (pd_len) {
+		iovec_num++;
+		iov[iovec_num].iov_base = (char *)pdata;
+		iov[iovec_num].iov_len = pd_len;
+		mpa_len += pd_len;
+	}
+	if (cep->enhanced_rdma_conn_est)
+		pd_len += sizeof(cep->mpa.v2_ctrl);
+
+	rr->params.pd_len = cpu_to_be16(pd_len);
+
+	rv = kernel_sendmsg(s, &msg, iov, iovec_num + 1, mpa_len);
+
+	return rv < 0 ? rv : 0;
+}
+
+/*
+ * Receive MPA Request/Reply header.
+ *
+ * Returns 0 if complete MPA Request/Reply header including
+ * eventual private data was received. Returns -EAGAIN if
+ * header was partially received or negative error code otherwise.
+ *
+ * Context: May be called in process context only
+ */
+static int siw_recv_mpa_rr(struct siw_cep *cep)
+{
+	struct mpa_rr *hdr = &cep->mpa.hdr;
+	struct socket *s = cep->sock;
+	u16 pd_len;
+	int rcvd, to_rcv;
+
+	if (cep->mpa.bytes_rcvd < sizeof(struct mpa_rr)) {
+		rcvd = ksock_recv(s, (char *)hdr + cep->mpa.bytes_rcvd,
+				  sizeof(struct mpa_rr) - cep->mpa.bytes_rcvd,
+				  0);
+		if (rcvd <= 0)
+			return -ECONNABORTED;
+
+		cep->mpa.bytes_rcvd += rcvd;
+
+		if (cep->mpa.bytes_rcvd < sizeof(struct mpa_rr))
+			return -EAGAIN;
+
+		if (be16_to_cpu(hdr->params.pd_len) > MPA_MAX_PRIVDATA)
+			return -EPROTO;
+	}
+	pd_len = be16_to_cpu(hdr->params.pd_len);
+
+	/*
+	 * At least the MPA Request/Reply header (frame not including
+	 * private data) has been received.
+	 * Receive (or continue receiving) any private data.
+	 */
+	to_rcv = pd_len - (cep->mpa.bytes_rcvd - sizeof(struct mpa_rr));
+
+	if (!to_rcv) {
+		/*
+		 * We must have hdr->params.pd_len == 0 and thus received a
+		 * complete MPA Request/Reply frame.
+		 * Check against peer protocol violation.
+		 */
+		u32 word;
+
+		rcvd = ksock_recv(s, (char *)&word, sizeof(word), MSG_DONTWAIT);
+		if (rcvd == -EAGAIN)
+			return 0;
+
+		if (rcvd == 0) {
+			siw_dbg_cep(cep, "peer EOF\n");
+			return -EPIPE;
+		}
+		if (rcvd < 0) {
+			siw_dbg_cep(cep, "error: %d\n", rcvd);
+			return rcvd;
+		}
+		siw_dbg_cep(cep, "peer sent extra data: %d\n", rcvd);
+
+		return -EPROTO;
+	}
+
+	/*
+	 * At this point, we must have hdr->params.pd_len != 0.
+	 * A private data buffer gets allocated if hdr->params.pd_len != 0.
+	 */
+	if (!cep->mpa.pdata) {
+		cep->mpa.pdata = kmalloc(pd_len + 4, GFP_KERNEL);
+		if (!cep->mpa.pdata)
+			return -ENOMEM;
+	}
+	rcvd = ksock_recv(
+		s, cep->mpa.pdata + cep->mpa.bytes_rcvd - sizeof(struct mpa_rr),
+		to_rcv + 4, MSG_DONTWAIT);
+
+	if (rcvd < 0)
+		return rcvd;
+
+	if (rcvd > to_rcv)
+		return -EPROTO;
+
+	cep->mpa.bytes_rcvd += rcvd;
+
+	if (to_rcv == rcvd) {
+		siw_dbg_cep(cep, "%d bytes private data received\n", pd_len);
+		return 0;
+	}
+	return -EAGAIN;
+}
+
+/*
+ * siw_proc_mpareq()
+ *
+ * Read MPA Request from socket and signal new connection to IWCM
+ * if success. Caller must hold lock on corresponding listening CEP.
+ */
+static int siw_proc_mpareq(struct siw_cep *cep)
+{
+	struct mpa_rr *req;
+	int version, rv;
+	u16 pd_len;
+
+	rv = siw_recv_mpa_rr(cep);
+	if (rv)
+		return rv;
+
+	req = &cep->mpa.hdr;
+
+	version = __mpa_rr_revision(req->params.bits);
+	pd_len = be16_to_cpu(req->params.pd_len);
+
+	if (version > MPA_REVISION_2)
+		/* allow for 0, 1, and 2 only */
+		return -EPROTO;
+
+	if (memcmp(req->key, MPA_KEY_REQ, 16))
+		return -EPROTO;
+
+	/* Prepare for sending MPA reply */
+	memcpy(req->key, MPA_KEY_REP, 16);
+
+	if (version == MPA_REVISION_2 &&
+	    (req->params.bits & MPA_RR_FLAG_ENHANCED)) {
+		/*
+		 * MPA version 2 must signal IRD/ORD values and P2P mode
+		 * in private data if header flag MPA_RR_FLAG_ENHANCED
+		 * is set.
+		 */
+		if (pd_len < sizeof(struct mpa_v2_data))
+			goto reject_conn;
+
+		cep->enhanced_rdma_conn_est = true;
+	}
+
+	/* MPA Markers: currently not supported. Marker TX to be added. */
+	if (req->params.bits & MPA_RR_FLAG_MARKERS)
+		goto reject_conn;
+
+	if (req->params.bits & MPA_RR_FLAG_CRC) {
+		/*
+		 * RFC 5044, page 27: CRC MUST be used if peer requests it.
+		 * siw specific: 'mpa_crc_strict' parameter to reject
+		 * connection with CRC if local CRC off enforced by
+		 * 'mpa_crc_strict' module parameter.
+		 */
+		if (!mpa_crc_required && mpa_crc_strict)
+			goto reject_conn;
+
+		/* Enable CRC if requested by module parameter */
+		if (mpa_crc_required)
+			req->params.bits |= MPA_RR_FLAG_CRC;
+	}
+	if (cep->enhanced_rdma_conn_est) {
+		struct mpa_v2_data *v2 = (struct mpa_v2_data *)cep->mpa.pdata;
+
+		/*
+		 * Peer requested ORD becomes requested local IRD,
+		 * peer requested IRD becomes requested local ORD.
+		 * IRD and ORD get limited by global maximum values.
+		 */
+		cep->ord = ntohs(v2->ird) & MPA_IRD_ORD_MASK;
+		cep->ord = min(cep->ord, SIW_MAX_ORD_QP);
+		cep->ird = ntohs(v2->ord) & MPA_IRD_ORD_MASK;
+		cep->ird = min(cep->ird, SIW_MAX_IRD_QP);
+
+		/* May get overwritten by locally negotiated values */
+		cep->mpa.v2_ctrl.ird = htons(cep->ird);
+		cep->mpa.v2_ctrl.ord = htons(cep->ord);
+
+		/*
+		 * Support for peer sent zero length Write or Read to
+		 * let local side enter RTS. Writes are preferred.
+		 * Sends would require pre-posting a Receive and are
+		 * not supported.
+		 * Propose zero length Write if none of Read and Write
+		 * is indicated.
+		 */
+		if (v2->ird & MPA_V2_PEER_TO_PEER) {
+			cep->mpa.v2_ctrl.ird |= MPA_V2_PEER_TO_PEER;
+
+			if (v2->ord & MPA_V2_RDMA_WRITE_RTR)
+				cep->mpa.v2_ctrl.ord |= MPA_V2_RDMA_WRITE_RTR;
+			else if (v2->ord & MPA_V2_RDMA_READ_RTR)
+				cep->mpa.v2_ctrl.ord |= MPA_V2_RDMA_READ_RTR;
+			else
+				cep->mpa.v2_ctrl.ord |= MPA_V2_RDMA_WRITE_RTR;
+		}
+	}
+
+	cep->state = SIW_EPSTATE_RECVD_MPAREQ;
+
+	/* Keep reference until IWCM accepts/rejects */
+	siw_cep_get(cep);
+	rv = siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REQUEST, 0);
+	if (rv)
+		siw_cep_put(cep);
+
+	return rv;
+
+reject_conn:
+	siw_dbg_cep(cep, "reject: crc %d:%d:%d, m %d:%d\n",
+		    req->params.bits & MPA_RR_FLAG_CRC ? 1 : 0,
+		    mpa_crc_required, mpa_crc_strict,
+		    req->params.bits & MPA_RR_FLAG_MARKERS ? 1 : 0, 0);
+
+	req->params.bits &= ~MPA_RR_FLAG_MARKERS;
+	req->params.bits |= MPA_RR_FLAG_REJECT;
+
+	if (!mpa_crc_required && mpa_crc_strict)
+		req->params.bits &= ~MPA_RR_FLAG_CRC;
+
+	if (pd_len)
+		kfree(cep->mpa.pdata);
+
+	cep->mpa.pdata = NULL;
+
+	siw_send_mpareqrep(cep, NULL, 0);
+
+	return -EOPNOTSUPP;
+}
+
+static int siw_proc_mpareply(struct siw_cep *cep)
+{
+	struct siw_qp_attrs qp_attrs;
+	enum siw_qp_attr_mask qp_attr_mask;
+	struct siw_qp *qp = cep->qp;
+	struct mpa_rr *rep;
+	int rv;
+	u16 rep_ord;
+	u16 rep_ird;
+	bool ird_insufficient = false;
+	enum mpa_v2_ctrl mpa_p2p_mode = MPA_V2_RDMA_NO_RTR;
+
+	rv = siw_recv_mpa_rr(cep);
+	if (rv != -EAGAIN)
+		siw_cancel_mpatimer(cep);
+	if (rv)
+		goto out_err;
+
+	rep = &cep->mpa.hdr;
+
+	if (__mpa_rr_revision(rep->params.bits) > MPA_REVISION_2) {
+		/* allow for 0, 1,  and 2 only */
+		rv = -EPROTO;
+		goto out_err;
+	}
+	if (memcmp(rep->key, MPA_KEY_REP, 16)) {
+		siw_init_terminate(qp, TERM_ERROR_LAYER_LLP, LLP_ETYPE_MPA,
+				   LLP_ECODE_INVALID_REQ_RESP, 0);
+		siw_send_terminate(qp);
+		rv = -EPROTO;
+		goto out_err;
+	}
+	if (rep->params.bits & MPA_RR_FLAG_REJECT) {
+		siw_dbg_cep(cep, "got mpa reject\n");
+		siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REPLY, -ECONNRESET);
+
+		return -ECONNRESET;
+	}
+	if (try_gso && rep->params.bits & MPA_RR_FLAG_GSO_EXP) {
+		siw_dbg_cep(cep, "peer allows GSO on TX\n");
+		qp->tx_ctx.gso_seg_limit = 0;
+	}
+	if ((rep->params.bits & MPA_RR_FLAG_MARKERS) ||
+	    (mpa_crc_required && !(rep->params.bits & MPA_RR_FLAG_CRC)) ||
+	    (mpa_crc_strict && !mpa_crc_required &&
+	     (rep->params.bits & MPA_RR_FLAG_CRC))) {
+		siw_dbg_cep(cep, "reply unsupp: crc %d:%d:%d, m %d:%d\n",
+			    rep->params.bits & MPA_RR_FLAG_CRC ? 1 : 0,
+			    mpa_crc_required, mpa_crc_strict,
+			    rep->params.bits & MPA_RR_FLAG_MARKERS ? 1 : 0, 0);
+
+		siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REPLY, -ECONNREFUSED);
+
+		return -EINVAL;
+	}
+	if (cep->enhanced_rdma_conn_est) {
+		struct mpa_v2_data *v2;
+
+		if (__mpa_rr_revision(rep->params.bits) < MPA_REVISION_2 ||
+		    !(rep->params.bits & MPA_RR_FLAG_ENHANCED)) {
+			/*
+			 * Protocol failure: The responder MUST reply with
+			 * MPA version 2 and MUST set MPA_RR_FLAG_ENHANCED.
+			 */
+			siw_dbg_cep(cep, "mpa reply error: vers %d, enhcd %d\n",
+				    __mpa_rr_revision(rep->params.bits),
+				    rep->params.bits & MPA_RR_FLAG_ENHANCED ?
+					    1 :
+					    0);
+
+			siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REPLY,
+				      -ECONNRESET);
+			return -EINVAL;
+		}
+		v2 = (struct mpa_v2_data *)cep->mpa.pdata;
+		rep_ird = ntohs(v2->ird) & MPA_IRD_ORD_MASK;
+		rep_ord = ntohs(v2->ord) & MPA_IRD_ORD_MASK;
+
+		if (cep->ird < rep_ord &&
+		    (relaxed_ird_negotiation == false ||
+		     rep_ord > cep->sdev->attrs.max_ird)) {
+			siw_dbg_cep(cep, "ird %d, rep_ord %d, max_ord %d\n",
+				    cep->ird, rep_ord,
+				    cep->sdev->attrs.max_ord);
+			ird_insufficient = true;
+		}
+		if (cep->ord > rep_ird && relaxed_ird_negotiation == false) {
+			siw_dbg_cep(cep, "ord %d, rep_ird %d\n", cep->ord,
+				    rep_ird);
+			ird_insufficient = true;
+		}
+		/*
+		 * Always report negotiated peer values to user,
+		 * even if IRD/ORD negotiation failed
+		 */
+		cep->ird = rep_ord;
+		cep->ord = rep_ird;
+
+		if (ird_insufficient) {
+			/*
+			 * If the initiator IRD is insuffient for the
+			 * responder ORD, send a TERM.
+			 */
+			siw_init_terminate(qp, TERM_ERROR_LAYER_LLP,
+					   LLP_ETYPE_MPA,
+					   LLP_ECODE_INSUFFICIENT_IRD, 0);
+			siw_send_terminate(qp);
+			rv = -ENOMEM;
+			goto out_err;
+		}
+		if (cep->mpa.v2_ctrl_req.ird & MPA_V2_PEER_TO_PEER)
+			mpa_p2p_mode =
+				cep->mpa.v2_ctrl_req.ord &
+				(MPA_V2_RDMA_WRITE_RTR | MPA_V2_RDMA_READ_RTR);
+
+		/*
+		 * Check if we requested P2P mode, and if peer agrees
+		 */
+		if (mpa_p2p_mode != MPA_V2_RDMA_NO_RTR) {
+			if ((mpa_p2p_mode & v2->ord) == 0) {
+				/*
+				 * We requested RTR mode(s), but the peer
+				 * did not pick any mode we support.
+				 */
+				siw_dbg_cep(cep,
+					    "rtr mode:  req %2x, got %2x\n",
+					    mpa_p2p_mode,
+					    v2->ord & (MPA_V2_RDMA_WRITE_RTR |
+						       MPA_V2_RDMA_READ_RTR));
+
+				siw_init_terminate(qp, TERM_ERROR_LAYER_LLP,
+						   LLP_ETYPE_MPA,
+						   LLP_ECODE_NO_MATCHING_RTR,
+						   0);
+				siw_send_terminate(qp);
+				rv = -EPROTO;
+				goto out_err;
+			}
+			mpa_p2p_mode = v2->ord & (MPA_V2_RDMA_WRITE_RTR |
+						  MPA_V2_RDMA_READ_RTR);
+		}
+	}
+	memset(&qp_attrs, 0, sizeof(qp_attrs));
+
+	if (rep->params.bits & MPA_RR_FLAG_CRC)
+		qp_attrs.flags = SIW_MPA_CRC;
+
+	qp_attrs.irq_size = cep->ird;
+	qp_attrs.orq_size = cep->ord;
+	qp_attrs.sk = cep->sock;
+	qp_attrs.state = SIW_QP_STATE_RTS;
+
+	qp_attr_mask = SIW_QP_ATTR_STATE | SIW_QP_ATTR_LLP_HANDLE |
+		       SIW_QP_ATTR_ORD | SIW_QP_ATTR_IRD | SIW_QP_ATTR_MPA;
+
+	/* Move socket RX/TX under QP control */
+	down_write(&qp->state_lock);
+	if (qp->attrs.state > SIW_QP_STATE_RTR) {
+		rv = -EINVAL;
+		up_write(&qp->state_lock);
+		goto out_err;
+	}
+	rv = siw_qp_modify(qp, &qp_attrs, qp_attr_mask);
+
+	siw_qp_socket_assoc(cep, qp);
+
+	up_write(&qp->state_lock);
+
+	/* Send extra RDMA frame to trigger peer RTS if negotiated */
+	if (mpa_p2p_mode != MPA_V2_RDMA_NO_RTR) {
+		rv = siw_qp_mpa_rts(qp, mpa_p2p_mode);
+		if (rv)
+			goto out_err;
+	}
+	if (!rv) {
+		rv = siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REPLY, 0);
+		if (!rv)
+			cep->state = SIW_EPSTATE_RDMA_MODE;
+
+		return 0;
+	}
+
+out_err:
+	siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REPLY, -EINVAL);
+
+	return rv;
+}
+
+/*
+ * siw_accept_newconn - accept an incoming pending connection
+ *
+ */
+static void siw_accept_newconn(struct siw_cep *cep)
+{
+	struct socket *s = cep->sock;
+	struct socket *new_s = NULL;
+	struct siw_cep *new_cep = NULL;
+	int rv = 0; /* debug only. should disappear */
+
+	if (cep->state != SIW_EPSTATE_LISTENING)
+		goto error;
+
+	new_cep = siw_cep_alloc(cep->sdev);
+	if (!new_cep)
+		goto error;
+
+	/*
+	 * 4: Allocate a sufficient number of work elements
+	 * to allow concurrent handling of local + peer close
+	 * events, MPA header processing + MPA timeout.
+	 */
+	if (siw_cm_alloc_work(new_cep, 4) != 0)
+		goto error;
+
+	/*
+	 * Copy saved socket callbacks from listening CEP
+	 * and assign new socket with new CEP
+	 */
+	new_cep->sk_state_change = cep->sk_state_change;
+	new_cep->sk_data_ready = cep->sk_data_ready;
+	new_cep->sk_write_space = cep->sk_write_space;
+	new_cep->sk_error_report = cep->sk_error_report;
+
+	rv = kernel_accept(s, &new_s, O_NONBLOCK);
+	if (rv != 0) {
+		/*
+		 * Connection already aborted by peer..?
+		 */
+		siw_dbg_cep(cep, "kernel_accept() error: %d\n", rv);
+		goto error;
+	}
+	new_cep->sock = new_s;
+	siw_cep_get(new_cep);
+	new_s->sk->sk_user_data = new_cep;
+
+	siw_dbg_cep(cep, "listen socket 0x%p, new 0x%p\n", s, new_s);
+
+	if (siw_tcp_nagle == false) {
+		int val = 1;
+
+		rv = kernel_setsockopt(new_s, SOL_TCP, TCP_NODELAY,
+				       (char *)&val, sizeof(val));
+		if (rv) {
+			siw_dbg_cep(cep, "setsockopt NODELAY error: %d\n", rv);
+			goto error;
+		}
+	}
+	new_cep->state = SIW_EPSTATE_AWAIT_MPAREQ;
+
+	rv = siw_cm_queue_work(new_cep, SIW_CM_WORK_MPATIMEOUT);
+	if (rv)
+		goto error;
+	/*
+	 * See siw_proc_mpareq() etc. for the use of new_cep->listen_cep.
+	 */
+	new_cep->listen_cep = cep;
+	siw_cep_get(cep);
+
+	if (atomic_read(&new_s->sk->sk_rmem_alloc)) {
+		/*
+		 * MPA REQ already queued
+		 */
+		siw_dbg_cep(cep, "immediate mpa request\n");
+
+		siw_cep_set_inuse(new_cep);
+		rv = siw_proc_mpareq(new_cep);
+		siw_cep_set_free(new_cep);
+
+		if (rv != -EAGAIN) {
+			siw_cep_put(cep);
+			new_cep->listen_cep = NULL;
+			if (rv)
+				goto error;
+		}
+	}
+	return;
+
+error:
+	if (new_cep)
+		siw_cep_put(new_cep);
+
+	if (new_s) {
+		siw_socket_disassoc(new_s);
+		sock_release(new_s);
+		new_cep->sock = NULL;
+	}
+	siw_dbg_cep(cep, "error %d\n", rv);
+}
+
+static void siw_cm_work_handler(struct work_struct *w)
+{
+	struct siw_cm_work *work;
+	struct siw_cep *cep;
+	int release_cep = 0, rv = 0;
+
+	work = container_of(w, struct siw_cm_work, work.work);
+	cep = work->cep;
+
+	siw_dbg_cep(cep, "[QP %u]: work type: %d, state %d\n",
+		    cep->qp ? qp_id(cep->qp) : -1, work->type, cep->state);
+
+	siw_cep_set_inuse(cep);
+
+	switch (work->type) {
+	case SIW_CM_WORK_ACCEPT:
+		siw_accept_newconn(cep);
+		break;
+
+	case SIW_CM_WORK_READ_MPAHDR:
+		if (cep->state == SIW_EPSTATE_AWAIT_MPAREQ) {
+			if (cep->listen_cep) {
+				siw_cep_set_inuse(cep->listen_cep);
+
+				if (cep->listen_cep->state ==
+				    SIW_EPSTATE_LISTENING)
+					rv = siw_proc_mpareq(cep);
+				else
+					rv = -EFAULT;
+
+				siw_cep_set_free(cep->listen_cep);
+
+				if (rv != -EAGAIN) {
+					siw_cep_put(cep->listen_cep);
+					cep->listen_cep = NULL;
+					if (rv)
+						siw_cep_put(cep);
+				}
+			}
+		} else if (cep->state == SIW_EPSTATE_AWAIT_MPAREP) {
+			rv = siw_proc_mpareply(cep);
+		} else {
+			/*
+			 * CEP already moved out of MPA handshake.
+			 * any connection management already done.
+			 * silently ignore the mpa packet.
+			 */
+			if (cep->state == SIW_EPSTATE_RDMA_MODE) {
+				cep->sock->sk->sk_data_ready(cep->sock->sk);
+				siw_dbg_cep(cep, "already in RDMA mode");
+			} else {
+				siw_dbg_cep(cep, "out of state: %d\n",
+					    cep->state);
+			}
+		}
+		if (rv && rv != EAGAIN)
+			release_cep = 1;
+		break;
+
+	case SIW_CM_WORK_CLOSE_LLP:
+		/*
+		 * QP scheduled LLP close
+		 */
+		if (cep->qp && cep->qp->term_info.valid)
+			siw_send_terminate(cep->qp);
+
+		if (cep->cm_id)
+			siw_cm_upcall(cep, IW_CM_EVENT_CLOSE, 0);
+
+		release_cep = 1;
+		break;
+
+	case SIW_CM_WORK_PEER_CLOSE:
+		if (cep->cm_id) {
+			if (cep->state == SIW_EPSTATE_AWAIT_MPAREP) {
+				/*
+				 * MPA reply not received, but connection drop
+				 */
+				siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REPLY,
+					      -ECONNRESET);
+			} else if (cep->state == SIW_EPSTATE_RDMA_MODE) {
+				/*
+				 * NOTE: IW_CM_EVENT_DISCONNECT is given just
+				 *       to transition IWCM into CLOSING.
+				 */
+				siw_cm_upcall(cep, IW_CM_EVENT_DISCONNECT, 0);
+				siw_cm_upcall(cep, IW_CM_EVENT_CLOSE, 0);
+			}
+			/*
+			 * for other states there is no connection
+			 * known to the IWCM.
+			 */
+		} else {
+			if (cep->state == SIW_EPSTATE_RECVD_MPAREQ) {
+				/*
+				 * Wait for the ulp/CM to call accept/reject
+				 */
+				siw_dbg_cep(cep,
+					    "mpa req recvd, wait for ULP\n");
+			} else if (cep->state == SIW_EPSTATE_AWAIT_MPAREQ) {
+				/*
+				 * Socket close before MPA request received.
+				 */
+				siw_dbg_cep(cep, "no mpareq: drop listener\n");
+				siw_cep_put(cep->listen_cep);
+				cep->listen_cep = NULL;
+			}
+		}
+		release_cep = 1;
+		break;
+
+	case SIW_CM_WORK_MPATIMEOUT:
+		cep->mpa_timer = NULL;
+
+		if (cep->state == SIW_EPSTATE_AWAIT_MPAREP) {
+			/*
+			 * MPA request timed out:
+			 * Hide any partially received private data and signal
+			 * timeout
+			 */
+			cep->mpa.hdr.params.pd_len = 0;
+
+			if (cep->cm_id)
+				siw_cm_upcall(cep, IW_CM_EVENT_CONNECT_REPLY,
+					      -ETIMEDOUT);
+			release_cep = 1;
+
+		} else if (cep->state == SIW_EPSTATE_AWAIT_MPAREQ) {
+			/*
+			 * No MPA request received after peer TCP stream setup.
+			 */
+			if (cep->listen_cep) {
+				siw_cep_put(cep->listen_cep);
+				cep->listen_cep = NULL;
+			}
+			release_cep = 1;
+		}
+		break;
+
+	default:
+		WARN(1, "Undefined CM work type: %d\n", work->type);
+	}
+	if (release_cep) {
+		siw_dbg_cep(cep,
+			    "release: timer=%s, QP[%u], id 0x%p\n",
+			    cep->mpa_timer ? "y" : "n",
+			    cep->qp ? qp_id(cep->qp) : -1, cep->cm_id);
+
+		siw_cancel_mpatimer(cep);
+
+		cep->state = SIW_EPSTATE_CLOSED;
+
+		if (cep->qp) {
+			struct siw_qp *qp = cep->qp;
+			/*
+			 * Serialize a potential race with application
+			 * closing the QP and calling siw_qp_cm_drop()
+			 */
+			siw_qp_get(qp);
+			siw_cep_set_free(cep);
+
+			siw_qp_llp_close(qp);
+			siw_qp_put(qp);
+
+			siw_cep_set_inuse(cep);
+			cep->qp = NULL;
+			siw_qp_put(qp);
+		}
+		if (cep->sock) {
+			siw_socket_disassoc(cep->sock);
+			sock_release(cep->sock);
+			cep->sock = NULL;
+		}
+		if (cep->cm_id) {
+			cep->cm_id->rem_ref(cep->cm_id);
+			cep->cm_id = NULL;
+			siw_cep_put(cep);
+		}
+	}
+	siw_cep_set_free(cep);
+	siw_put_work(work);
+	siw_cep_put(cep);
+}
+
+static struct workqueue_struct *siw_cm_wq;
+
+int siw_cm_queue_work(struct siw_cep *cep, enum siw_work_type type)
+{
+	struct siw_cm_work *work = siw_get_work(cep);
+	unsigned long delay = 0;
+
+	if (!work) {
+		siw_dbg_cep(cep, "failed with no work available\n");
+		return -ENOMEM;
+	}
+	work->type = type;
+	work->cep = cep;
+
+	siw_cep_get(cep);
+
+	INIT_DELAYED_WORK(&work->work, siw_cm_work_handler);
+
+	if (type == SIW_CM_WORK_MPATIMEOUT) {
+		cep->mpa_timer = work;
+
+		if (cep->state == SIW_EPSTATE_AWAIT_MPAREP)
+			delay = MPAREQ_TIMEOUT;
+		else
+			delay = MPAREP_TIMEOUT;
+	}
+	siw_dbg_cep(cep, "[QP %u]: work type: %d, work 0x%p, timeout %lu\n",
+		    cep->qp ? qp_id(cep->qp) : -1, type, work, delay);
+
+	queue_delayed_work(siw_cm_wq, &work->work, delay);
+
+	return 0;
+}
+
+static void siw_cm_llp_data_ready(struct sock *sk)
+{
+	struct siw_cep *cep;
+
+	read_lock(&sk->sk_callback_lock);
+
+	cep = sk_to_cep(sk);
+	if (!cep) {
+		WARN_ON(1);
+		goto out;
+	}
+	siw_dbg_cep(cep, "state: %d\n", cep->state);
+
+	switch (cep->state) {
+	case SIW_EPSTATE_RDMA_MODE:
+		/* fall through */
+	case SIW_EPSTATE_LISTENING:
+		break;
+
+	case SIW_EPSTATE_AWAIT_MPAREQ:
+		/* fall through */
+	case SIW_EPSTATE_AWAIT_MPAREP:
+		siw_cm_queue_work(cep, SIW_CM_WORK_READ_MPAHDR);
+		break;
+
+	default:
+		siw_dbg_cep(cep, "unexpected data, state %d\n", cep->state);
+		break;
+	}
+out:
+	read_unlock(&sk->sk_callback_lock);
+}
+
+static void siw_cm_llp_write_space(struct sock *sk)
+{
+	struct siw_cep *cep = sk_to_cep(sk);
+
+	if (cep)
+		siw_dbg_cep(cep, "state: %d\n", cep->state);
+}
+
+static void siw_cm_llp_error_report(struct sock *sk)
+{
+	struct siw_cep *cep = sk_to_cep(sk);
+
+	if (cep) {
+		siw_dbg_cep(cep, "error %d, socket state: %d, cep state: %d\n",
+			    sk->sk_err, sk->sk_state, cep->state);
+		cep->sk_error_report(sk);
+	}
+}
+
+static void siw_cm_llp_state_change(struct sock *sk)
+{
+	struct siw_cep *cep;
+	struct socket *s;
+	void (*orig_state_change)(struct sock *s);
+
+	read_lock(&sk->sk_callback_lock);
+
+	cep = sk_to_cep(sk);
+	if (!cep) {
+		/* endpoint already disassociated */
+		read_unlock(&sk->sk_callback_lock);
+		return;
+	}
+	orig_state_change = cep->sk_state_change;
+
+	s = sk->sk_socket;
+
+	siw_dbg_cep(cep, "state: %d\n", cep->state);
+
+	switch (sk->sk_state) {
+	case TCP_ESTABLISHED:
+		/*
+		 * handle accepting socket as special case where only
+		 * new connection is possible
+		 */
+		siw_cm_queue_work(cep, SIW_CM_WORK_ACCEPT);
+		break;
+
+	case TCP_CLOSE:
+	case TCP_CLOSE_WAIT:
+		if (cep->qp)
+			cep->qp->tx_ctx.tx_suspend = 1;
+		siw_cm_queue_work(cep, SIW_CM_WORK_PEER_CLOSE);
+		break;
+
+	default:
+		siw_dbg_cep(cep, "unexpected socket state %d\n", sk->sk_state);
+	}
+	read_unlock(&sk->sk_callback_lock);
+	orig_state_change(sk);
+}
+
+static int kernel_bindconnect(struct socket *s, struct sockaddr *laddr,
+			      struct sockaddr *raddr)
+{
+	int rv, flags = 0, s_val = 1;
+	size_t size = laddr->sa_family == AF_INET ?
+		sizeof(struct sockaddr_in) : sizeof(struct sockaddr_in6);
+
+	/*
+	 * Make address available again asap.
+	 */
+	rv = kernel_setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char *)&s_val,
+			       sizeof(s_val));
+	if (rv < 0)
+		return rv;
+
+	rv = s->ops->bind(s, laddr, size);
+	if (rv < 0)
+		return rv;
+
+	rv = s->ops->connect(s, raddr, size, flags);
+
+	return rv < 0 ? rv : 0;
+}
+
+int siw_connect(struct iw_cm_id *id, struct iw_cm_conn_param *params)
+{
+	struct siw_device *sdev = to_siw_dev(id->device);
+	struct siw_qp *qp;
+	struct siw_cep *cep = NULL;
+	struct socket *s = NULL;
+	struct sockaddr *laddr = (struct sockaddr *)&id->local_addr,
+			*raddr = (struct sockaddr *)&id->remote_addr;
+	bool p2p_mode = peer_to_peer, v4 = true;
+	u16 pd_len = params->private_data_len;
+	int version = mpa_version, rv;
+
+	if (pd_len > MPA_MAX_PRIVDATA)
+		return -EINVAL;
+
+	if (params->ird > sdev->attrs.max_ird ||
+	    params->ord > sdev->attrs.max_ord)
+		return -ENOMEM;
+
+	if (laddr->sa_family == AF_INET6)
+		v4 = false;
+	else if (laddr->sa_family != AF_INET)
+		return -EAFNOSUPPORT;
+
+	/*
+	 * Respect any iwarp port mapping: Use mapped remote address
+	 * if valid. Local address must not be mapped, since siw
+	 * uses kernel TCP stack.
+	 */
+	if ((v4 && to_sockaddr_in(id->remote_addr).sin_port != 0) ||
+	     to_sockaddr_in6(id->remote_addr).sin6_port != 0)
+		raddr = (struct sockaddr *)&id->m_remote_addr;
+
+	qp = siw_qp_id2obj(sdev, params->qpn);
+	if (!qp) {
+		WARN(1, "[QP %u] does not exist\n", params->qpn);
+		rv = -EINVAL;
+		goto error;
+	}
+	if (v4)
+		siw_dbg_qp(qp,
+			   "id 0x%p, pd_len %d, laddr %pI4 %d, raddr %pI4 %d\n",
+			   id, pd_len,
+			   &((struct sockaddr_in *)(laddr))->sin_addr,
+			   ntohs(((struct sockaddr_in *)(laddr))->sin_port),
+			   &((struct sockaddr_in *)(raddr))->sin_addr,
+			   ntohs(((struct sockaddr_in *)(raddr))->sin_port));
+	else
+		siw_dbg_qp(qp,
+			   "id 0x%p, pd_len %d, laddr %pI6 %d, raddr %pI6 %d\n",
+			   id, pd_len,
+			   &((struct sockaddr_in6 *)(laddr))->sin6_addr,
+			   ntohs(((struct sockaddr_in6 *)(laddr))->sin6_port),
+			   &((struct sockaddr_in6 *)(raddr))->sin6_addr,
+			   ntohs(((struct sockaddr_in6 *)(raddr))->sin6_port));
+
+	rv = sock_create(v4 ? AF_INET : AF_INET6, SOCK_STREAM, IPPROTO_TCP, &s);
+	if (rv < 0)
+		goto error;
+
+	/*
+	 * NOTE: For simplification, connect() is called in blocking
+	 * mode. Might be reconsidered for async connection setup at
+	 * TCP level.
+	 */
+	rv = kernel_bindconnect(s, laddr, raddr);
+	if (rv != 0) {
+		siw_dbg_qp(qp, "kernel_bindconnect: error %d\n", rv);
+		goto error;
+	}
+	if (siw_tcp_nagle == false) {
+		int val = 1;
+
+		rv = kernel_setsockopt(s, SOL_TCP, TCP_NODELAY, (char *)&val,
+				       sizeof(val));
+		if (rv) {
+			siw_dbg_qp(qp, "setsockopt NODELAY error: %d\n", rv);
+			goto error;
+		}
+	}
+	cep = siw_cep_alloc(sdev);
+	if (!cep) {
+		rv = -ENOMEM;
+		goto error;
+	}
+	siw_cep_set_inuse(cep);
+
+	/* Associate QP with CEP */
+	siw_cep_get(cep);
+	qp->cep = cep;
+
+	/* siw_qp_get(qp) already done by QP lookup */
+	cep->qp = qp;
+
+	id->add_ref(id);
+	cep->cm_id = id;
+
+	/*
+	 * 4: Allocate a sufficient number of work elements
+	 * to allow concurrent handling of local + peer close
+	 * events, MPA header processing + MPA timeout.
+	 */
+	rv = siw_cm_alloc_work(cep, 4);
+	if (rv != 0) {
+		rv = -ENOMEM;
+		goto error;
+	}
+	cep->ird = params->ird;
+	cep->ord = params->ord;
+
+	if (p2p_mode && cep->ord == 0)
+		cep->ord = 1;
+
+	cep->state = SIW_EPSTATE_CONNECTING;
+
+	/*
+	 * Associate CEP with socket
+	 */
+	siw_cep_socket_assoc(cep, s);
+
+	cep->state = SIW_EPSTATE_AWAIT_MPAREP;
+
+	/*
+	 * Set MPA Request bits: CRC if required, no MPA Markers,
+	 * MPA Rev. according to module parameter 'mpa_version', Key 'Request'.
+	 */
+	cep->mpa.hdr.params.bits = 0;
+	if (version > MPA_REVISION_2) {
+		pr_warn("Setting MPA version to %u\n", MPA_REVISION_2);
+		version = MPA_REVISION_2;
+		/* Adjust also module parameter */
+		mpa_version = MPA_REVISION_2;
+	}
+	__mpa_rr_set_revision(&cep->mpa.hdr.params.bits, version);
+
+	if (try_gso)
+		cep->mpa.hdr.params.bits |= MPA_RR_FLAG_GSO_EXP;
+
+	if (mpa_crc_required)
+		cep->mpa.hdr.params.bits |= MPA_RR_FLAG_CRC;
+
+	/*
+	 * If MPA version == 2:
+	 * o Include ORD and IRD.
+	 * o Indicate peer-to-peer mode, if required by module
+	 *   parameter 'peer_to_peer'.
+	 */
+	if (version == MPA_REVISION_2) {
+		cep->enhanced_rdma_conn_est = true;
+		cep->mpa.hdr.params.bits |= MPA_RR_FLAG_ENHANCED;
+
+		cep->mpa.v2_ctrl.ird = htons(cep->ird);
+		cep->mpa.v2_ctrl.ord = htons(cep->ord);
+
+		if (p2p_mode) {
+			cep->mpa.v2_ctrl.ird |= MPA_V2_PEER_TO_PEER;
+			cep->mpa.v2_ctrl.ord |= rtr_type;
+		}
+		/* Remember own P2P mode requested */
+		cep->mpa.v2_ctrl_req.ird = cep->mpa.v2_ctrl.ird;
+		cep->mpa.v2_ctrl_req.ord = cep->mpa.v2_ctrl.ord;
+	}
+	memcpy(cep->mpa.hdr.key, MPA_KEY_REQ, 16);
+
+	rv = siw_send_mpareqrep(cep, params->private_data, pd_len);
+	/*
+	 * Reset private data.
+	 */
+	cep->mpa.hdr.params.pd_len = 0;
+
+	if (rv >= 0) {
+		rv = siw_cm_queue_work(cep, SIW_CM_WORK_MPATIMEOUT);
+		if (!rv) {
+			siw_dbg_cep(cep, "id 0x%p, [QP %u]: exit\n", id,
+				    qp_id(qp));
+			siw_cep_set_free(cep);
+			return 0;
+		}
+	}
+error:
+	siw_dbg_qp(qp, "failed: %d\n", rv);
+
+	if (cep) {
+		siw_socket_disassoc(s);
+		sock_release(s);
+		cep->sock = NULL;
+
+		cep->qp = NULL;
+
+		cep->cm_id = NULL;
+		id->rem_ref(id);
+		siw_cep_put(cep);
+
+		qp->cep = NULL;
+		siw_cep_put(cep);
+
+		cep->state = SIW_EPSTATE_CLOSED;
+
+		siw_cep_set_free(cep);
+
+		siw_cep_put(cep);
+
+	} else if (s) {
+		sock_release(s);
+	}
+	siw_qp_put(qp);
+
+	return rv;
+}
+
+/*
+ * siw_accept - Let SoftiWARP accept an RDMA connection request
+ *
+ * @id:		New connection management id to be used for accepted
+ *		connection request
+ * @params:	Connection parameters provided by ULP for accepting connection
+ *
+ * Transition QP to RTS state, associate new CM id @id with accepted CEP
+ * and get prepared for TCP input by installing socket callbacks.
+ * Then send MPA Reply and generate the "connection established" event.
+ * Socket callbacks must be installed before sending MPA Reply, because
+ * the latter may cause a first RDMA message to arrive from the RDMA Initiator
+ * side very quickly, at which time the socket callbacks must be ready.
+ */
+int siw_accept(struct iw_cm_id *id, struct iw_cm_conn_param *params)
+{
+	struct siw_device *sdev = to_siw_dev(id->device);
+	struct siw_cep *cep = (struct siw_cep *)id->provider_data;
+	struct siw_qp *qp;
+	struct siw_qp_attrs qp_attrs;
+	int rv, max_priv_data = MPA_MAX_PRIVDATA;
+	bool wait_for_peer_rts = false;
+
+	siw_cep_set_inuse(cep);
+	siw_cep_put(cep);
+
+	/* Free lingering inbound private data */
+	if (cep->mpa.hdr.params.pd_len) {
+		cep->mpa.hdr.params.pd_len = 0;
+		kfree(cep->mpa.pdata);
+		cep->mpa.pdata = NULL;
+	}
+	siw_cancel_mpatimer(cep);
+
+	if (cep->state != SIW_EPSTATE_RECVD_MPAREQ) {
+		siw_dbg_cep(cep, "id 0x%p: out of state\n", id);
+
+		siw_cep_set_free(cep);
+		siw_cep_put(cep);
+
+		return -ECONNRESET;
+	}
+	qp = siw_qp_id2obj(sdev, params->qpn);
+	if (!qp) {
+		WARN(1, "[QP %d] does not exist\n", params->qpn);
+		siw_cep_set_free(cep);
+		siw_cep_put(cep);
+
+		return -EINVAL;
+	}
+	down_write(&qp->state_lock);
+	if (qp->attrs.state > SIW_QP_STATE_RTR) {
+		rv = -EINVAL;
+		up_write(&qp->state_lock);
+		goto error;
+	}
+	siw_dbg_cep(cep, "id 0x%p\n", id);
+
+	if (try_gso && cep->mpa.hdr.params.bits & MPA_RR_FLAG_GSO_EXP) {
+		siw_dbg_cep(cep, "peer allows GSO on TX\n");
+		qp->tx_ctx.gso_seg_limit = 0;
+	}
+	if (params->ord > sdev->attrs.max_ord ||
+	    params->ird > sdev->attrs.max_ird) {
+		siw_dbg_cep(
+			cep,
+			"id 0x%p, [QP %u]: ord %d (max %d), ird %d (max %d)\n",
+			id, qp_id(qp), params->ord, sdev->attrs.max_ord,
+			params->ird, sdev->attrs.max_ird);
+		rv = -EINVAL;
+		up_write(&qp->state_lock);
+		goto error;
+	}
+	if (cep->enhanced_rdma_conn_est)
+		max_priv_data -= sizeof(struct mpa_v2_data);
+
+	if (params->private_data_len > max_priv_data) {
+		siw_dbg_cep(
+			cep,
+			"id 0x%p, [QP %u]: private data length: %d (max %d)\n",
+			id, qp_id(qp), params->private_data_len, max_priv_data);
+		rv = -EINVAL;
+		up_write(&qp->state_lock);
+		goto error;
+	}
+	if (cep->enhanced_rdma_conn_est) {
+		if (params->ord > cep->ord) {
+			if (relaxed_ird_negotiation) {
+				params->ord = cep->ord;
+			} else {
+				cep->ird = params->ird;
+				cep->ord = params->ord;
+				rv = -EINVAL;
+				up_write(&qp->state_lock);
+				goto error;
+			}
+		}
+		if (params->ird < cep->ird) {
+			if (relaxed_ird_negotiation &&
+			    cep->ird <= sdev->attrs.max_ird)
+				params->ird = cep->ird;
+			else {
+				rv = -ENOMEM;
+				up_write(&qp->state_lock);
+				goto error;
+			}
+		}
+		if (cep->mpa.v2_ctrl.ord &
+		    (MPA_V2_RDMA_WRITE_RTR | MPA_V2_RDMA_READ_RTR))
+			wait_for_peer_rts = true;
+		/*
+		 * Signal back negotiated IRD and ORD values
+		 */
+		cep->mpa.v2_ctrl.ord =
+			htons(params->ord & MPA_IRD_ORD_MASK) |
+			(cep->mpa.v2_ctrl.ord & ~MPA_V2_MASK_IRD_ORD);
+		cep->mpa.v2_ctrl.ird =
+			htons(params->ird & MPA_IRD_ORD_MASK) |
+			(cep->mpa.v2_ctrl.ird & ~MPA_V2_MASK_IRD_ORD);
+	}
+	cep->ird = params->ird;
+	cep->ord = params->ord;
+
+	cep->cm_id = id;
+	id->add_ref(id);
+
+	memset(&qp_attrs, 0, sizeof(qp_attrs));
+	qp_attrs.orq_size = cep->ord;
+	qp_attrs.irq_size = cep->ird;
+	qp_attrs.sk = cep->sock;
+	if (cep->mpa.hdr.params.bits & MPA_RR_FLAG_CRC)
+		qp_attrs.flags = SIW_MPA_CRC;
+	qp_attrs.state = SIW_QP_STATE_RTS;
+
+	siw_dbg_cep(cep, "id 0x%p, [QP%u]: moving to rts\n", id, qp_id(qp));
+
+	/* Associate QP with CEP */
+	siw_cep_get(cep);
+	qp->cep = cep;
+
+	/* siw_qp_get(qp) already done by QP lookup */
+	cep->qp = qp;
+
+	cep->state = SIW_EPSTATE_RDMA_MODE;
+
+	/* Move socket RX/TX under QP control */
+	rv = siw_qp_modify(qp, &qp_attrs,
+			   SIW_QP_ATTR_STATE | SIW_QP_ATTR_LLP_HANDLE |
+				   SIW_QP_ATTR_ORD | SIW_QP_ATTR_IRD |
+				   SIW_QP_ATTR_MPA);
+	up_write(&qp->state_lock);
+
+	if (rv)
+		goto error;
+
+	siw_dbg_cep(cep, "id 0x%p, [QP %u]: send mpa reply, %d byte pdata\n",
+		    id, qp_id(qp), params->private_data_len);
+
+	rv = siw_send_mpareqrep(cep, params->private_data,
+				params->private_data_len);
+	if (rv != 0)
+		goto error;
+
+	if (wait_for_peer_rts) {
+		siw_sk_assign_rtr_upcalls(cep);
+	} else {
+		siw_qp_socket_assoc(cep, qp);
+		rv = siw_cm_upcall(cep, IW_CM_EVENT_ESTABLISHED, 0);
+		if (rv)
+			goto error;
+	}
+	siw_cep_set_free(cep);
+
+	return 0;
+error:
+	siw_socket_disassoc(cep->sock);
+	sock_release(cep->sock);
+	cep->sock = NULL;
+
+	cep->state = SIW_EPSTATE_CLOSED;
+
+	if (cep->cm_id) {
+		cep->cm_id->rem_ref(id);
+		cep->cm_id = NULL;
+	}
+	if (qp->cep) {
+		siw_cep_put(cep);
+		qp->cep = NULL;
+	}
+	cep->qp = NULL;
+	siw_qp_put(qp);
+
+	siw_cep_set_free(cep);
+	siw_cep_put(cep);
+
+	return rv;
+}
+
+/*
+ * siw_reject()
+ *
+ * Local connection reject case. Send private data back to peer,
+ * close connection and dereference connection id.
+ */
+int siw_reject(struct iw_cm_id *id, const void *pdata, u8 pd_len)
+{
+	struct siw_cep *cep = (struct siw_cep *)id->provider_data;
+
+	siw_cep_set_inuse(cep);
+	siw_cep_put(cep);
+
+	siw_cancel_mpatimer(cep);
+
+	if (cep->state != SIW_EPSTATE_RECVD_MPAREQ) {
+		siw_dbg_cep(cep, "id 0x%p: out of state\n", id);
+
+		siw_cep_set_free(cep);
+		siw_cep_put(cep); /* put last reference */
+
+		return -ECONNRESET;
+	}
+	siw_dbg_cep(cep, "id 0x%p, cep->state %d, pd_len %d\n", id, cep->state,
+		    pd_len);
+
+	if (__mpa_rr_revision(cep->mpa.hdr.params.bits) >= MPA_REVISION_1) {
+		cep->mpa.hdr.params.bits |= MPA_RR_FLAG_REJECT; /* reject */
+		siw_send_mpareqrep(cep, pdata, pd_len);
+	}
+	siw_socket_disassoc(cep->sock);
+	sock_release(cep->sock);
+	cep->sock = NULL;
+
+	cep->state = SIW_EPSTATE_CLOSED;
+
+	siw_cep_set_free(cep);
+	siw_cep_put(cep);
+
+	return 0;
+}
+
+static int siw_listen_address(struct iw_cm_id *id, int backlog,
+			      struct sockaddr *laddr, int addr_family)
+{
+	struct socket *s;
+	struct siw_cep *cep = NULL;
+	struct siw_device *sdev = to_siw_dev(id->device);
+	int rv = 0, s_val;
+
+	rv = sock_create(addr_family, SOCK_STREAM, IPPROTO_TCP, &s);
+	if (rv < 0)
+		return rv;
+
+	/*
+	 * Allow binding local port when still in TIME_WAIT from last close.
+	 */
+	s_val = 1;
+	rv = kernel_setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char *)&s_val,
+			       sizeof(s_val));
+	if (rv) {
+		siw_dbg(id->device, "id 0x%p: setsockopt error: %d\n", id, rv);
+		goto error;
+	}
+	rv = s->ops->bind(s, laddr, addr_family == AF_INET ?
+				    sizeof(struct sockaddr_in) :
+				    sizeof(struct sockaddr_in6));
+	if (rv) {
+		siw_dbg(id->device, "id 0x%p: socket bind error: %d\n", id, rv);
+		goto error;
+	}
+	cep = siw_cep_alloc(sdev);
+	if (!cep) {
+		rv = -ENOMEM;
+		goto error;
+	}
+	siw_cep_socket_assoc(cep, s);
+
+	rv = siw_cm_alloc_work(cep, backlog);
+	if (rv) {
+		siw_dbg(id->device,
+			"id 0x%p: alloc_work error %d, backlog %d\n", id,
+			rv, backlog);
+		goto error;
+	}
+	rv = s->ops->listen(s, backlog);
+	if (rv) {
+		siw_dbg(id->device, "id 0x%p: listen error %d\n", id, rv);
+		goto error;
+	}
+	cep->cm_id = id;
+	id->add_ref(id);
+
+	/*
+	 * In case of a wildcard rdma_listen on a multi-homed device,
+	 * a listener's IWCM id is associated with more than one listening CEP.
+	 *
+	 * We currently use id->provider_data in three different ways:
+	 *
+	 * o For a listener's IWCM id, id->provider_data points to
+	 *   the list_head of the list of listening CEPs.
+	 *   Uses: siw_create_listen(), siw_destroy_listen()
+	 *
+	 * o For each accepted passive-side IWCM id, id->provider_data
+	 *   points to the CEP itself. This is a consequence of
+	 *   - siw_cm_upcall() setting event.provider_data = cep and
+	 *   - the IWCM's cm_conn_req_handler() setting provider_data of the
+	 *     new passive-side IWCM id equal to event.provider_data
+	 *   Uses: siw_accept(), siw_reject()
+	 *
+	 * o For an active-side IWCM id, id->provider_data is not used at all.
+	 *
+	 */
+	if (!id->provider_data) {
+		id->provider_data =
+			kmalloc(sizeof(struct list_head), GFP_KERNEL);
+		if (!id->provider_data) {
+			rv = -ENOMEM;
+			goto error;
+		}
+		INIT_LIST_HEAD((struct list_head *)id->provider_data);
+	}
+	list_add_tail(&cep->listenq, (struct list_head *)id->provider_data);
+	cep->state = SIW_EPSTATE_LISTENING;
+
+	if (addr_family == AF_INET)
+		siw_dbg(id->device, "Listen at laddr %pI4 %u\n",
+			&(((struct sockaddr_in *)laddr)->sin_addr),
+			((struct sockaddr_in *)laddr)->sin_port);
+	else
+		siw_dbg(id->device, "Listen at laddr %pI6 %u\n",
+			&(((struct sockaddr_in6 *)laddr)->sin6_addr),
+			((struct sockaddr_in6 *)laddr)->sin6_port);
+
+	return 0;
+
+error:
+	siw_dbg(id->device, "failed: %d\n", rv);
+
+	if (cep) {
+		siw_cep_set_inuse(cep);
+
+		if (cep->cm_id) {
+			cep->cm_id->rem_ref(cep->cm_id);
+			cep->cm_id = NULL;
+		}
+		cep->sock = NULL;
+		siw_socket_disassoc(s);
+		cep->state = SIW_EPSTATE_CLOSED;
+
+		siw_cep_set_free(cep);
+		siw_cep_put(cep);
+	}
+	sock_release(s);
+
+	return rv;
+}
+
+static void siw_drop_listeners(struct iw_cm_id *id)
+{
+	struct list_head *p, *tmp;
+
+	/*
+	 * In case of a wildcard rdma_listen on a multi-homed device,
+	 * a listener's IWCM id is associated with more than one listening CEP.
+	 */
+	list_for_each_safe(p, tmp, (struct list_head *)id->provider_data) {
+		struct siw_cep *cep = list_entry(p, struct siw_cep, listenq);
+
+		list_del(p);
+
+		siw_dbg_cep(cep, "id 0x%p: drop cep, state %d\n", id,
+			    cep->state);
+
+		siw_cep_set_inuse(cep);
+
+		if (cep->cm_id) {
+			cep->cm_id->rem_ref(cep->cm_id);
+			cep->cm_id = NULL;
+		}
+		if (cep->sock) {
+			siw_socket_disassoc(cep->sock);
+			sock_release(cep->sock);
+			cep->sock = NULL;
+		}
+		cep->state = SIW_EPSTATE_CLOSED;
+		siw_cep_set_free(cep);
+		siw_cep_put(cep);
+	}
+}
+
+/*
+ * siw_create_listen - Create resources for a listener's IWCM ID @id
+ *
+ * Listens on the socket addresses id->local_addr and id->remote_addr.
+ *
+ * If the listener's @id provides a specific local IP address, at most one
+ * listening socket is created and associated with @id.
+ *
+ * If the listener's @id provides the wildcard (zero) local IP address,
+ * a separate listen is performed for each local IP address of the device
+ * by creating a listening socket and binding to that local IP address.
+ *
+ */
+int siw_create_listen(struct iw_cm_id *id, int backlog)
+{
+	struct net_device *dev = to_siw_dev(id->device)->netdev;
+	int rv = 0, listeners = 0;
+
+	siw_dbg(id->device, "id 0x%p: backlog %d\n", id, backlog);
+
+	/*
+	 * For each attached address of the interface, create a
+	 * listening socket, if id->local_addr is the wildcard
+	 * IP address or matches the IP address.
+	 */
+	if (id->local_addr.ss_family == AF_INET) {
+		struct in_device *in_dev = in_dev_get(dev);
+		struct sockaddr_in s_laddr, *s_raddr;
+
+		memcpy(&s_laddr, &id->local_addr, sizeof(s_laddr));
+		s_raddr = (struct sockaddr_in *)&id->remote_addr;
+
+		siw_dbg(id->device,
+			"id 0x%p: laddr %pI4:%d, raddr %pI4:%d\n",
+			id, &s_laddr.sin_addr, ntohs(s_laddr.sin_port),
+			&s_raddr->sin_addr, ntohs(s_raddr->sin_port));
+
+		for_ifa(in_dev)
+		{
+			if (ipv4_is_zeronet(s_laddr.sin_addr.s_addr) ||
+			    s_laddr.sin_addr.s_addr == ifa->ifa_address) {
+				s_laddr.sin_addr.s_addr = ifa->ifa_address;
+
+				rv = siw_listen_address(id, backlog,
+						(struct sockaddr *)&s_laddr,
+						AF_INET);
+				if (!rv)
+					listeners++;
+			}
+		}
+		endfor_ifa(in_dev);
+		in_dev_put(in_dev);
+	} else if (id->local_addr.ss_family == AF_INET6) {
+		struct inet6_dev *in6_dev = in6_dev_get(dev);
+		struct inet6_ifaddr *ifp;
+		struct sockaddr_in6 *s_laddr = &to_sockaddr_in6(id->local_addr),
+			*s_raddr = &to_sockaddr_in6(id->remote_addr);
+
+		siw_dbg(id->device,
+			"id 0x%p: laddr %pI6:%d, raddr %pI6:%d\n",
+			id, &s_laddr->sin6_addr, ntohs(s_laddr->sin6_port),
+			&s_raddr->sin6_addr, ntohs(s_raddr->sin6_port));
+
+		read_lock_bh(&in6_dev->lock);
+		list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
+			struct sockaddr_in6 bind_addr;
+
+			if (ipv6_addr_any(&s_laddr->sin6_addr) ||
+			    ipv6_addr_equal(&s_laddr->sin6_addr, &ifp->addr)) {
+				bind_addr.sin6_family = AF_INET6;
+				bind_addr.sin6_port = s_laddr->sin6_port;
+				bind_addr.sin6_flowinfo = 0;
+				bind_addr.sin6_addr = ifp->addr;
+				bind_addr.sin6_scope_id = dev->ifindex;
+
+				rv = siw_listen_address(id, backlog,
+						(struct sockaddr *)&bind_addr,
+						AF_INET6);
+				if (!rv)
+					listeners++;
+			}
+		}
+		read_unlock_bh(&in6_dev->lock);
+
+		in6_dev_put(in6_dev);
+	} else {
+		return -EAFNOSUPPORT;
+	}
+	if (listeners)
+		rv = 0;
+	else if (!rv)
+		rv = -EINVAL;
+
+	siw_dbg(id->device, "id 0x%p: %s\n", id, rv ? "FAIL" : "OK");
+
+	return rv;
+}
+
+int siw_destroy_listen(struct iw_cm_id *id)
+{
+	siw_dbg(id->device, "id 0x%p\n", id);
+
+	if (!id->provider_data) {
+		siw_dbg(id->device, "id 0x%p: no cep(s)\n", id);
+		return 0;
+	}
+	siw_drop_listeners(id);
+	kfree(id->provider_data);
+	id->provider_data = NULL;
+
+	return 0;
+}
+
+int siw_cm_init(void)
+{
+	/*
+	 * create_single_workqueue for strict ordering
+	 */
+	siw_cm_wq = create_singlethread_workqueue("siw_cm_wq");
+	if (!siw_cm_wq)
+		return -ENOMEM;
+
+	return 0;
+}
+
+void siw_cm_exit(void)
+{
+	if (siw_cm_wq) {
+		flush_workqueue(siw_cm_wq);
+		destroy_workqueue(siw_cm_wq);
+	}
+}
diff --git a/drivers/infiniband/sw/siw/siw_cm.h b/drivers/infiniband/sw/siw/siw_cm.h
new file mode 100644
index 000000000000..8c59cb3e2868
--- /dev/null
+++ b/drivers/infiniband/sw/siw/siw_cm.h
@@ -0,0 +1,133 @@
+/* SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause */
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/*          Greg Joyce <greg@opengridcomputing.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+/* Copyright (c) 2017, Open Grid Computing, Inc. */
+
+#ifndef _SIW_CM_H
+#define _SIW_CM_H
+
+#include <net/sock.h>
+#include <linux/tcp.h>
+
+#include <rdma/iw_cm.h>
+
+enum siw_cep_state {
+	SIW_EPSTATE_IDLE = 1,
+	SIW_EPSTATE_LISTENING,
+	SIW_EPSTATE_CONNECTING,
+	SIW_EPSTATE_AWAIT_MPAREQ,
+	SIW_EPSTATE_RECVD_MPAREQ,
+	SIW_EPSTATE_AWAIT_MPAREP,
+	SIW_EPSTATE_RDMA_MODE,
+	SIW_EPSTATE_CLOSED
+};
+
+struct siw_mpa_info {
+	struct mpa_rr hdr; /* peer mpa hdr in host byte order */
+	struct mpa_v2_data v2_ctrl;
+	struct mpa_v2_data v2_ctrl_req;
+	char *pdata;
+	int bytes_rcvd;
+};
+
+struct siw_device;
+
+struct siw_cep {
+	struct iw_cm_id *cm_id;
+	struct siw_device *sdev;
+	struct list_head devq;
+	spinlock_t lock;
+	struct kref ref;
+	int in_use;
+	wait_queue_head_t waitq;
+	enum siw_cep_state state;
+
+	struct list_head listenq;
+	struct siw_cep *listen_cep;
+
+	struct siw_qp *qp;
+	struct socket *sock;
+
+	struct siw_cm_work *mpa_timer;
+	struct list_head work_freelist;
+
+	struct siw_mpa_info mpa;
+	int ord;
+	int ird;
+	bool enhanced_rdma_conn_est;
+
+	/* Saved upcalls of socket */
+	void (*sk_state_change)(struct sock *sk);
+	void (*sk_data_ready)(struct sock *sk);
+	void (*sk_write_space)(struct sock *sk);
+	void (*sk_error_report)(struct sock *sk);
+};
+
+/*
+ * Connection initiator waits 10 seconds to receive an
+ * MPA reply after sending out MPA request. Reponder waits for
+ * 5 seconds for MPA request to arrive if new TCP connection
+ * was set up.
+ */
+#define MPAREQ_TIMEOUT (HZ * 10)
+#define MPAREP_TIMEOUT (HZ * 5)
+
+enum siw_work_type {
+	SIW_CM_WORK_ACCEPT = 1,
+	SIW_CM_WORK_READ_MPAHDR,
+	SIW_CM_WORK_CLOSE_LLP, /* close socket */
+	SIW_CM_WORK_PEER_CLOSE, /* socket indicated peer close */
+	SIW_CM_WORK_MPATIMEOUT
+};
+
+struct siw_cm_work {
+	struct delayed_work work;
+	struct list_head list;
+	enum siw_work_type type;
+	struct siw_cep *cep;
+};
+
+#define to_sockaddr_in(a) (*(struct sockaddr_in *)(&(a)))
+#define to_sockaddr_in6(a) (*(struct sockaddr_in6 *)(&(a)))
+
+static inline int getname_peer(struct socket *s, struct sockaddr_storage *a)
+{
+	return s->ops->getname(s, (struct sockaddr *)a, 1);
+}
+
+static inline int getname_local(struct socket *s, struct sockaddr_storage *a)
+{
+	return s->ops->getname(s, (struct sockaddr *)a, 0);
+}
+
+static inline int ksock_recv(struct socket *sock, char *buf, size_t size,
+			     int flags)
+{
+	struct kvec iov = { buf, size };
+	struct msghdr msg = { .msg_name = NULL, .msg_flags = flags };
+
+	return kernel_recvmsg(sock, &msg, &iov, 1, size, flags);
+}
+
+int siw_connect(struct iw_cm_id *id, struct iw_cm_conn_param *parm);
+int siw_accept(struct iw_cm_id *id, struct iw_cm_conn_param *param);
+int siw_reject(struct iw_cm_id *id, const void *data, u8 len);
+int siw_create_listen(struct iw_cm_id *id, int backlog);
+int siw_destroy_listen(struct iw_cm_id *id);
+
+void siw_cep_get(struct siw_cep *cep);
+void siw_cep_put(struct siw_cep *cep);
+int siw_cm_queue_work(struct siw_cep *cep, enum siw_work_type type);
+
+int siw_cm_init(void);
+void siw_cm_exit(void);
+
+/*
+ * TCP socket interface
+ */
+#define sk_to_qp(sk) (((struct siw_cep *)((sk)->sk_user_data))->qp)
+#define sk_to_cep(sk) ((struct siw_cep *)((sk)->sk_user_data))
+
+#endif
diff --git a/drivers/infiniband/sw/siw/siw_cq.c b/drivers/infiniband/sw/siw/siw_cq.c
new file mode 100644
index 000000000000..e2a0ee40d5b5
--- /dev/null
+++ b/drivers/infiniband/sw/siw/siw_cq.c
@@ -0,0 +1,101 @@
+// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+
+#include <rdma/ib_verbs.h>
+
+#include "siw.h"
+
+static int map_wc_opcode[SIW_NUM_OPCODES] = {
+	[SIW_OP_WRITE] = IB_WC_RDMA_WRITE,
+	[SIW_OP_SEND] = IB_WC_SEND,
+	[SIW_OP_SEND_WITH_IMM] = IB_WC_SEND,
+	[SIW_OP_READ] = IB_WC_RDMA_READ,
+	[SIW_OP_READ_LOCAL_INV] = IB_WC_RDMA_READ,
+	[SIW_OP_COMP_AND_SWAP] = IB_WC_COMP_SWAP,
+	[SIW_OP_FETCH_AND_ADD] = IB_WC_FETCH_ADD,
+	[SIW_OP_INVAL_STAG] = IB_WC_LOCAL_INV,
+	[SIW_OP_REG_MR] = IB_WC_REG_MR,
+	[SIW_OP_RECEIVE] = IB_WC_RECV,
+	[SIW_OP_READ_RESPONSE] = -1 /* not used */
+};
+
+static struct {
+	enum siw_opcode siw;
+	enum ib_wc_status ib;
+} map_cqe_status[SIW_NUM_WC_STATUS] = {
+	{ SIW_WC_SUCCESS, IB_WC_SUCCESS },
+	{ SIW_WC_LOC_LEN_ERR, IB_WC_LOC_LEN_ERR },
+	{ SIW_WC_LOC_PROT_ERR, IB_WC_LOC_PROT_ERR },
+	{ SIW_WC_LOC_QP_OP_ERR, IB_WC_LOC_QP_OP_ERR },
+	{ SIW_WC_WR_FLUSH_ERR, IB_WC_WR_FLUSH_ERR },
+	{ SIW_WC_BAD_RESP_ERR, IB_WC_BAD_RESP_ERR },
+	{ SIW_WC_LOC_ACCESS_ERR, IB_WC_LOC_ACCESS_ERR },
+	{ SIW_WC_REM_ACCESS_ERR, IB_WC_REM_ACCESS_ERR },
+	{ SIW_WC_REM_INV_REQ_ERR, IB_WC_REM_INV_REQ_ERR },
+	{ SIW_WC_GENERAL_ERR, IB_WC_GENERAL_ERR }
+};
+
+/*
+ * Reap one CQE from the CQ. Only used by kernel clients
+ * during CQ normal operation. Might be called during CQ
+ * flush for user mapped CQE array as well.
+ */
+int siw_reap_cqe(struct siw_cq *cq, struct ib_wc *wc)
+{
+	struct siw_cqe *cqe;
+	unsigned long flags;
+
+	spin_lock_irqsave(&cq->lock, flags);
+
+	cqe = &cq->queue[cq->cq_get % cq->num_cqe];
+	if (READ_ONCE(cqe->flags) & SIW_WQE_VALID) {
+		memset(wc, 0, sizeof(*wc));
+		wc->wr_id = cqe->id;
+		wc->status = map_cqe_status[cqe->status].ib;
+		wc->opcode = map_wc_opcode[cqe->opcode];
+		wc->byte_len = cqe->bytes;
+
+		/*
+		 * During CQ flush, also user land CQE's may get
+		 * reaped here, which do not hold a QP reference
+		 * and do not qualify for memory extension verbs.
+		 */
+		if (likely(cq->kernel_verbs)) {
+			if (cqe->flags & SIW_WQE_REM_INVAL) {
+				wc->ex.invalidate_rkey = cqe->inval_stag;
+				wc->wc_flags = IB_WC_WITH_INVALIDATE;
+			}
+			wc->qp = cqe->base_qp;
+			siw_dbg_cq(cq, "idx %u, type %d, flags %2x, id 0x%p\n",
+				   cq->cq_get % cq->num_cqe, cqe->opcode,
+				   cqe->flags, (void *)cqe->id);
+		}
+		WRITE_ONCE(cqe->flags, 0);
+		cq->cq_get++;
+
+		spin_unlock_irqrestore(&cq->lock, flags);
+
+		return 1;
+	}
+	spin_unlock_irqrestore(&cq->lock, flags);
+
+	return 0;
+}
+
+/*
+ * siw_cq_flush()
+ *
+ * Flush all CQ elements.
+ */
+void siw_cq_flush(struct siw_cq *cq)
+{
+	struct ib_wc wc;
+
+	while (siw_reap_cqe(cq, &wc))
+		;
+}
diff --git a/drivers/infiniband/sw/siw/siw_main.c b/drivers/infiniband/sw/siw/siw_main.c
new file mode 100644
index 000000000000..3f5f3d27ebe5
--- /dev/null
+++ b/drivers/infiniband/sw/siw/siw_main.c
@@ -0,0 +1,687 @@
+// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/netdevice.h>
+#include <linux/inetdevice.h>
+#include <net/net_namespace.h>
+#include <linux/rtnetlink.h>
+#include <linux/if_arp.h>
+#include <linux/list.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/module.h>
+#include <linux/dma-mapping.h>
+
+#include <rdma/ib_verbs.h>
+#include <rdma/ib_user_verbs.h>
+#include <rdma/rdma_netlink.h>
+#include <linux/kthread.h>
+
+#include "siw.h"
+#include "siw_verbs.h"
+
+MODULE_AUTHOR("Bernard Metzler");
+MODULE_DESCRIPTION("Software iWARP Driver");
+MODULE_LICENSE("Dual BSD/GPL");
+
+/* transmit from user buffer, if possible */
+const bool zcopy_tx = true;
+
+/* Restrict usage of GSO, if hardware peer iwarp is unable to process
+ * large packets. try_gso = true lets siw try to use local GSO,
+ * if peer agrees.  Not using GSO severly limits siw maximum tx bandwidth.
+ */
+const bool try_gso;
+
+/* Attach siw also with loopback devices */
+const bool loopback_enabled = true;
+
+/* We try to negotiate CRC on, if true */
+const bool mpa_crc_required;
+
+/* MPA CRC on/off enforced */
+const bool mpa_crc_strict;
+
+/* Control TCP_NODELAY socket option */
+const bool siw_tcp_nagle;
+
+/* Select MPA version to be used during connection setup */
+u_char mpa_version = MPA_REVISION_2;
+
+/* Selects MPA P2P mode (additional handshake during connection
+ * setup, if true.
+ */
+const bool peer_to_peer;
+
+struct task_struct *siw_tx_thread[NR_CPUS];
+struct crypto_shash *siw_crypto_shash;
+
+static int siw_device_register(struct siw_device *sdev, const char *name)
+{
+	struct ib_device *base_dev = &sdev->base_dev;
+	static int dev_id = 1;
+	int rv;
+
+	rv = ib_register_device(base_dev, name);
+	if (rv) {
+		pr_warn("siw: device registration error %d\n", rv);
+		return rv;
+	}
+	sdev->vendor_part_id = dev_id++;
+
+	siw_dbg(base_dev, "HWaddr=%pM\n", sdev->netdev->dev_addr);
+
+	return 0;
+}
+
+static void siw_device_cleanup(struct ib_device *base_dev)
+{
+	struct siw_device *sdev = to_siw_dev(base_dev);
+
+	xa_destroy(&sdev->qp_xa);
+	xa_destroy(&sdev->mem_xa);
+}
+
+static int siw_create_tx_threads(void)
+{
+	int cpu, rv, assigned = 0;
+
+	for_each_online_cpu(cpu) {
+		/* Skip HT cores */
+		if (cpu % cpumask_weight(topology_sibling_cpumask(cpu)))
+			continue;
+
+		siw_tx_thread[cpu] =
+			kthread_create(siw_run_sq, (unsigned long *)(long)cpu,
+				       "siw_tx/%d", cpu);
+		if (IS_ERR(siw_tx_thread[cpu])) {
+			rv = PTR_ERR(siw_tx_thread[cpu]);
+			siw_tx_thread[cpu] = NULL;
+			pr_info("Creating TX thread for CPU %d failed", cpu);
+			continue;
+		}
+		kthread_bind(siw_tx_thread[cpu], cpu);
+
+		wake_up_process(siw_tx_thread[cpu]);
+		assigned++;
+	}
+	return assigned;
+}
+
+static int siw_dev_qualified(struct net_device *netdev)
+{
+	/*
+	 * Additional hardware support can be added here
+	 * (e.g. ARPHRD_FDDI, ARPHRD_ATM, ...) - see
+	 * <linux/if_arp.h> for type identifiers.
+	 */
+	if (netdev->type == ARPHRD_ETHER || netdev->type == ARPHRD_IEEE802 ||
+	    (netdev->type == ARPHRD_LOOPBACK && loopback_enabled))
+		return 1;
+
+	return 0;
+}
+
+static DEFINE_PER_CPU(atomic_t, use_cnt = ATOMIC_INIT(0));
+
+static struct {
+	struct cpumask **tx_valid_cpus;
+	int num_nodes;
+} siw_cpu_info;
+
+static int siw_init_cpulist(void)
+{
+	int i, num_nodes = num_possible_nodes();
+
+	memset(siw_tx_thread, 0, sizeof(siw_tx_thread));
+
+	siw_cpu_info.num_nodes = num_nodes;
+
+	siw_cpu_info.tx_valid_cpus =
+		kcalloc(num_nodes, sizeof(struct cpumask *), GFP_KERNEL);
+	if (!siw_cpu_info.tx_valid_cpus) {
+		siw_cpu_info.num_nodes = 0;
+		return -ENOMEM;
+	}
+	for (i = 0; i < siw_cpu_info.num_nodes; i++) {
+		siw_cpu_info.tx_valid_cpus[i] =
+			kzalloc(sizeof(struct cpumask), GFP_KERNEL);
+		if (!siw_cpu_info.tx_valid_cpus[i])
+			goto out_err;
+
+		cpumask_clear(siw_cpu_info.tx_valid_cpus[i]);
+	}
+	for_each_possible_cpu(i)
+		cpumask_set_cpu(i, siw_cpu_info.tx_valid_cpus[cpu_to_node(i)]);
+
+	return 0;
+
+out_err:
+	siw_cpu_info.num_nodes = 0;
+	while (i) {
+		kfree(siw_cpu_info.tx_valid_cpus[i]);
+		siw_cpu_info.tx_valid_cpus[i--] = NULL;
+	}
+	kfree(siw_cpu_info.tx_valid_cpus);
+	siw_cpu_info.tx_valid_cpus = NULL;
+
+	return -ENOMEM;
+}
+
+static void siw_destroy_cpulist(void)
+{
+	int i = 0;
+
+	while (i < siw_cpu_info.num_nodes)
+		kfree(siw_cpu_info.tx_valid_cpus[i++]);
+
+	kfree(siw_cpu_info.tx_valid_cpus);
+}
+
+/*
+ * Choose CPU with least number of active QP's from NUMA node of
+ * TX interface.
+ */
+int siw_get_tx_cpu(struct siw_device *sdev)
+{
+	const struct cpumask *tx_cpumask;
+	int i, num_cpus, cpu, min_use, node = sdev->numa_node, tx_cpu = -1;
+
+	if (node < 0)
+		tx_cpumask = cpu_online_mask;
+	else
+		tx_cpumask = siw_cpu_info.tx_valid_cpus[node];
+
+	num_cpus = cpumask_weight(tx_cpumask);
+	if (!num_cpus) {
+		/* no CPU on this NUMA node */
+		tx_cpumask = cpu_online_mask;
+		num_cpus = cpumask_weight(tx_cpumask);
+	}
+	if (!num_cpus)
+		goto out;
+
+	cpu = cpumask_first(tx_cpumask);
+
+	for (i = 0, min_use = SIW_MAX_QP; i < num_cpus;
+	     i++, cpu = cpumask_next(cpu, tx_cpumask)) {
+		int usage;
+
+		/* Skip any cores which have no TX thread */
+		if (!siw_tx_thread[cpu])
+			continue;
+
+		usage = atomic_read(&per_cpu(use_cnt, cpu));
+		if (usage <= min_use) {
+			tx_cpu = cpu;
+			min_use = usage;
+		}
+	}
+	siw_dbg(&sdev->base_dev,
+		"tx cpu %d, node %d, %d qp's\n", tx_cpu, node, min_use);
+
+out:
+	if (tx_cpu >= 0)
+		atomic_inc(&per_cpu(use_cnt, tx_cpu));
+	else
+		pr_warn("siw: no tx cpu found\n");
+
+	return tx_cpu;
+}
+
+void siw_put_tx_cpu(int cpu)
+{
+	atomic_dec(&per_cpu(use_cnt, cpu));
+}
+
+static struct ib_qp *siw_get_base_qp(struct ib_device *base_dev, int id)
+{
+	struct siw_qp *qp = siw_qp_id2obj(to_siw_dev(base_dev), id);
+
+	if (qp) {
+		/*
+		 * siw_qp_id2obj() increments object reference count
+		 */
+		siw_qp_put(qp);
+		return qp->ib_qp;
+	}
+	return NULL;
+}
+
+static void siw_verbs_sq_flush(struct ib_qp *base_qp)
+{
+	struct siw_qp *qp = to_siw_qp(base_qp);
+
+	down_write(&qp->state_lock);
+	siw_sq_flush(qp);
+	up_write(&qp->state_lock);
+}
+
+static void siw_verbs_rq_flush(struct ib_qp *base_qp)
+{
+	struct siw_qp *qp = to_siw_qp(base_qp);
+
+	down_write(&qp->state_lock);
+	siw_rq_flush(qp);
+	up_write(&qp->state_lock);
+}
+
+static const struct ib_device_ops siw_device_ops = {
+	.owner = THIS_MODULE,
+	.uverbs_abi_ver = SIW_ABI_VERSION,
+	.driver_id = RDMA_DRIVER_SIW,
+
+	.alloc_mr = siw_alloc_mr,
+	.alloc_pd = siw_alloc_pd,
+	.alloc_ucontext = siw_alloc_ucontext,
+	.create_cq = siw_create_cq,
+	.create_qp = siw_create_qp,
+	.create_srq = siw_create_srq,
+	.dealloc_driver = siw_device_cleanup,
+	.dealloc_pd = siw_dealloc_pd,
+	.dealloc_ucontext = siw_dealloc_ucontext,
+	.dereg_mr = siw_dereg_mr,
+	.destroy_cq = siw_destroy_cq,
+	.destroy_qp = siw_destroy_qp,
+	.destroy_srq = siw_destroy_srq,
+	.drain_rq = siw_verbs_rq_flush,
+	.drain_sq = siw_verbs_sq_flush,
+	.get_dma_mr = siw_get_dma_mr,
+	.get_port_immutable = siw_get_port_immutable,
+	.iw_accept = siw_accept,
+	.iw_add_ref = siw_qp_get_ref,
+	.iw_connect = siw_connect,
+	.iw_create_listen = siw_create_listen,
+	.iw_destroy_listen = siw_destroy_listen,
+	.iw_get_qp = siw_get_base_qp,
+	.iw_reject = siw_reject,
+	.iw_rem_ref = siw_qp_put_ref,
+	.map_mr_sg = siw_map_mr_sg,
+	.mmap = siw_mmap,
+	.modify_qp = siw_verbs_modify_qp,
+	.modify_srq = siw_modify_srq,
+	.poll_cq = siw_poll_cq,
+	.post_recv = siw_post_receive,
+	.post_send = siw_post_send,
+	.post_srq_recv = siw_post_srq_recv,
+	.query_device = siw_query_device,
+	.query_gid = siw_query_gid,
+	.query_pkey = siw_query_pkey,
+	.query_port = siw_query_port,
+	.query_qp = siw_query_qp,
+	.query_srq = siw_query_srq,
+	.req_notify_cq = siw_req_notify_cq,
+	.reg_user_mr = siw_reg_user_mr,
+
+	INIT_RDMA_OBJ_SIZE(ib_cq, siw_cq, base_cq),
+	INIT_RDMA_OBJ_SIZE(ib_pd, siw_pd, base_pd),
+	INIT_RDMA_OBJ_SIZE(ib_srq, siw_srq, base_srq),
+	INIT_RDMA_OBJ_SIZE(ib_ucontext, siw_ucontext, base_ucontext),
+};
+
+static struct siw_device *siw_device_create(struct net_device *netdev)
+{
+	struct siw_device *sdev = NULL;
+	struct ib_device *base_dev;
+	struct device *parent = netdev->dev.parent;
+	int rv;
+
+	if (!parent) {
+		/*
+		 * The loopback device has no parent device,
+		 * so it appears as a top-level device. To support
+		 * loopback device connectivity, take this device
+		 * as the parent device. Skip all other devices
+		 * w/o parent device.
+		 */
+		if (netdev->type != ARPHRD_LOOPBACK) {
+			pr_warn("siw: device %s error: no parent device\n",
+				netdev->name);
+			return NULL;
+		}
+		parent = &netdev->dev;
+	}
+	sdev = ib_alloc_device(siw_device, base_dev);
+	if (!sdev)
+		return NULL;
+
+	base_dev = &sdev->base_dev;
+
+	sdev->netdev = netdev;
+
+	if (netdev->type != ARPHRD_LOOPBACK) {
+		memcpy(&base_dev->node_guid, netdev->dev_addr, 6);
+	} else {
+		/*
+		 * The loopback device does not have a HW address,
+		 * but connection mangagement lib expects gid != 0
+		 */
+		size_t gidlen = min_t(size_t, strlen(base_dev->name), 6);
+
+		memcpy(&base_dev->node_guid, base_dev->name, gidlen);
+	}
+	base_dev->uverbs_cmd_mask =
+		(1ull << IB_USER_VERBS_CMD_QUERY_DEVICE) |
+		(1ull << IB_USER_VERBS_CMD_QUERY_PORT) |
+		(1ull << IB_USER_VERBS_CMD_GET_CONTEXT) |
+		(1ull << IB_USER_VERBS_CMD_ALLOC_PD) |
+		(1ull << IB_USER_VERBS_CMD_DEALLOC_PD) |
+		(1ull << IB_USER_VERBS_CMD_REG_MR) |
+		(1ull << IB_USER_VERBS_CMD_DEREG_MR) |
+		(1ull << IB_USER_VERBS_CMD_CREATE_COMP_CHANNEL) |
+		(1ull << IB_USER_VERBS_CMD_CREATE_CQ) |
+		(1ull << IB_USER_VERBS_CMD_POLL_CQ) |
+		(1ull << IB_USER_VERBS_CMD_REQ_NOTIFY_CQ) |
+		(1ull << IB_USER_VERBS_CMD_DESTROY_CQ) |
+		(1ull << IB_USER_VERBS_CMD_CREATE_QP) |
+		(1ull << IB_USER_VERBS_CMD_QUERY_QP) |
+		(1ull << IB_USER_VERBS_CMD_MODIFY_QP) |
+		(1ull << IB_USER_VERBS_CMD_DESTROY_QP) |
+		(1ull << IB_USER_VERBS_CMD_POST_SEND) |
+		(1ull << IB_USER_VERBS_CMD_POST_RECV) |
+		(1ull << IB_USER_VERBS_CMD_CREATE_SRQ) |
+		(1ull << IB_USER_VERBS_CMD_POST_SRQ_RECV) |
+		(1ull << IB_USER_VERBS_CMD_MODIFY_SRQ) |
+		(1ull << IB_USER_VERBS_CMD_QUERY_SRQ) |
+		(1ull << IB_USER_VERBS_CMD_DESTROY_SRQ);
+
+	base_dev->node_type = RDMA_NODE_RNIC;
+	memcpy(base_dev->node_desc, SIW_NODE_DESC_COMMON,
+	       sizeof(SIW_NODE_DESC_COMMON));
+
+	/*
+	 * Current model (one-to-one device association):
+	 * One Softiwarp device per net_device or, equivalently,
+	 * per physical port.
+	 */
+	base_dev->phys_port_cnt = 1;
+	base_dev->dev.parent = parent;
+	base_dev->dev.dma_ops = &dma_virt_ops;
+	base_dev->num_comp_vectors = num_possible_cpus();
+
+	ib_set_device_ops(base_dev, &siw_device_ops);
+	rv = ib_device_set_netdev(base_dev, netdev, 1);
+	if (rv)
+		goto error;
+
+	memcpy(base_dev->iw_ifname, netdev->name,
+	       sizeof(base_dev->iw_ifname));
+
+	/* Disable TCP port mapping */
+	base_dev->iw_driver_flags = IW_F_NO_PORT_MAP,
+
+	sdev->attrs.max_qp = SIW_MAX_QP;
+	sdev->attrs.max_qp_wr = SIW_MAX_QP_WR;
+	sdev->attrs.max_ord = SIW_MAX_ORD_QP;
+	sdev->attrs.max_ird = SIW_MAX_IRD_QP;
+	sdev->attrs.max_sge = SIW_MAX_SGE;
+	sdev->attrs.max_sge_rd = SIW_MAX_SGE_RD;
+	sdev->attrs.max_cq = SIW_MAX_CQ;
+	sdev->attrs.max_cqe = SIW_MAX_CQE;
+	sdev->attrs.max_mr = SIW_MAX_MR;
+	sdev->attrs.max_pd = SIW_MAX_PD;
+	sdev->attrs.max_mw = SIW_MAX_MW;
+	sdev->attrs.max_fmr = SIW_MAX_FMR;
+	sdev->attrs.max_srq = SIW_MAX_SRQ;
+	sdev->attrs.max_srq_wr = SIW_MAX_SRQ_WR;
+	sdev->attrs.max_srq_sge = SIW_MAX_SGE;
+
+	xa_init_flags(&sdev->qp_xa, XA_FLAGS_ALLOC1);
+	xa_init_flags(&sdev->mem_xa, XA_FLAGS_ALLOC1);
+
+	INIT_LIST_HEAD(&sdev->cep_list);
+	INIT_LIST_HEAD(&sdev->qp_list);
+
+	atomic_set(&sdev->num_ctx, 0);
+	atomic_set(&sdev->num_srq, 0);
+	atomic_set(&sdev->num_qp, 0);
+	atomic_set(&sdev->num_cq, 0);
+	atomic_set(&sdev->num_mr, 0);
+	atomic_set(&sdev->num_pd, 0);
+
+	sdev->numa_node = dev_to_node(parent);
+	spin_lock_init(&sdev->lock);
+
+	return sdev;
+error:
+	ib_dealloc_device(base_dev);
+
+	return NULL;
+}
+
+/*
+ * Network link becomes unavailable. Mark all
+ * affected QP's accordingly.
+ */
+static void siw_netdev_down(struct work_struct *work)
+{
+	struct siw_device *sdev =
+		container_of(work, struct siw_device, netdev_down);
+
+	struct siw_qp_attrs qp_attrs;
+	struct list_head *pos, *tmp;
+
+	memset(&qp_attrs, 0, sizeof(qp_attrs));
+	qp_attrs.state = SIW_QP_STATE_ERROR;
+
+	list_for_each_safe(pos, tmp, &sdev->qp_list) {
+		struct siw_qp *qp = list_entry(pos, struct siw_qp, devq);
+
+		down_write(&qp->state_lock);
+		WARN_ON(siw_qp_modify(qp, &qp_attrs, SIW_QP_ATTR_STATE));
+		up_write(&qp->state_lock);
+	}
+	ib_device_put(&sdev->base_dev);
+}
+
+static void siw_device_goes_down(struct siw_device *sdev)
+{
+	if (ib_device_try_get(&sdev->base_dev)) {
+		INIT_WORK(&sdev->netdev_down, siw_netdev_down);
+		schedule_work(&sdev->netdev_down);
+	}
+}
+
+static int siw_netdev_event(struct notifier_block *nb, unsigned long event,
+			    void *arg)
+{
+	struct net_device *netdev = netdev_notifier_info_to_dev(arg);
+	struct ib_device *base_dev;
+	struct siw_device *sdev;
+
+	dev_dbg(&netdev->dev, "siw: event %lu\n", event);
+
+	if (dev_net(netdev) != &init_net)
+		return NOTIFY_OK;
+
+	base_dev = ib_device_get_by_netdev(netdev, RDMA_DRIVER_SIW);
+	if (!base_dev)
+		return NOTIFY_OK;
+
+	sdev = to_siw_dev(base_dev);
+
+	switch (event) {
+	case NETDEV_UP:
+		sdev->state = IB_PORT_ACTIVE;
+		siw_port_event(sdev, 1, IB_EVENT_PORT_ACTIVE);
+		break;
+
+	case NETDEV_GOING_DOWN:
+		siw_device_goes_down(sdev);
+		break;
+
+	case NETDEV_DOWN:
+		sdev->state = IB_PORT_DOWN;
+		siw_port_event(sdev, 1, IB_EVENT_PORT_ERR);
+		break;
+
+	case NETDEV_REGISTER:
+		/*
+		 * Device registration now handled only by
+		 * rdma netlink commands. So it shall be impossible
+		 * to end up here with a valid siw device.
+		 */
+		siw_dbg(base_dev, "unexpected NETDEV_REGISTER event\n");
+		break;
+
+	case NETDEV_UNREGISTER:
+		ib_unregister_device_queued(&sdev->base_dev);
+		break;
+
+	case NETDEV_CHANGEADDR:
+		siw_port_event(sdev, 1, IB_EVENT_LID_CHANGE);
+		break;
+	/*
+	 * Todo: Below netdev events are currently not handled.
+	 */
+	case NETDEV_CHANGEMTU:
+	case NETDEV_CHANGE:
+		break;
+
+	default:
+		break;
+	}
+	ib_device_put(&sdev->base_dev);
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block siw_netdev_nb = {
+	.notifier_call = siw_netdev_event,
+};
+
+static int siw_newlink(const char *basedev_name, struct net_device *netdev)
+{
+	struct ib_device *base_dev;
+	struct siw_device *sdev = NULL;
+	int rv = -ENOMEM;
+
+	if (!siw_dev_qualified(netdev))
+		return -EINVAL;
+
+	base_dev = ib_device_get_by_netdev(netdev, RDMA_DRIVER_SIW);
+	if (base_dev) {
+		ib_device_put(base_dev);
+		return -EEXIST;
+	}
+	sdev = siw_device_create(netdev);
+	if (sdev) {
+		dev_dbg(&netdev->dev, "siw: new device\n");
+
+		if (netif_running(netdev) && netif_carrier_ok(netdev))
+			sdev->state = IB_PORT_ACTIVE;
+		else
+			sdev->state = IB_PORT_DOWN;
+
+		rv = siw_device_register(sdev, basedev_name);
+		if (rv)
+			ib_dealloc_device(&sdev->base_dev);
+	}
+	return rv;
+}
+
+static struct rdma_link_ops siw_link_ops = {
+	.type = "siw",
+	.newlink = siw_newlink,
+};
+
+/*
+ * siw_init_module - Initialize Softiwarp module and register with netdev
+ *                   subsystem.
+ */
+static __init int siw_init_module(void)
+{
+	int rv;
+	int nr_cpu;
+
+	if (SENDPAGE_THRESH < SIW_MAX_INLINE) {
+		pr_info("siw: sendpage threshold too small: %u\n",
+			(int)SENDPAGE_THRESH);
+		rv = -EINVAL;
+		goto out_error;
+	}
+	rv = siw_init_cpulist();
+	if (rv)
+		goto out_error;
+
+	rv = siw_cm_init();
+	if (rv)
+		goto out_error;
+
+	if (!siw_create_tx_threads()) {
+		pr_info("siw: Could not start any TX thread\n");
+		goto out_error;
+	}
+	/*
+	 * Locate CRC32 algorithm. If unsuccessful, fail
+	 * loading siw only, if CRC is required.
+	 */
+	siw_crypto_shash = crypto_alloc_shash("crc32c", 0, 0);
+	if (IS_ERR(siw_crypto_shash)) {
+		pr_info("siw: Loading CRC32c failed: %ld\n",
+			PTR_ERR(siw_crypto_shash));
+		siw_crypto_shash = NULL;
+		if (mpa_crc_required) {
+			rv = -EOPNOTSUPP;
+			goto out_error;
+		}
+	}
+	rv = register_netdevice_notifier(&siw_netdev_nb);
+	if (rv)
+		goto out_error;
+
+	rdma_link_register(&siw_link_ops);
+
+	pr_info("SoftiWARP attached\n");
+	return 0;
+
+out_error:
+	for (nr_cpu = 0; nr_cpu < nr_cpu_ids; nr_cpu++) {
+		if (siw_tx_thread[nr_cpu]) {
+			siw_stop_tx_thread(nr_cpu);
+			siw_tx_thread[nr_cpu] = NULL;
+		}
+	}
+	if (siw_crypto_shash)
+		crypto_free_shash(siw_crypto_shash);
+
+	pr_info("SoftIWARP attach failed. Error: %d\n", rv);
+
+	siw_cm_exit();
+	siw_destroy_cpulist();
+
+	return rv;
+}
+
+static void __exit siw_exit_module(void)
+{
+	int cpu;
+
+	for_each_possible_cpu(cpu) {
+		if (siw_tx_thread[cpu]) {
+			siw_stop_tx_thread(cpu);
+			siw_tx_thread[cpu] = NULL;
+		}
+	}
+	unregister_netdevice_notifier(&siw_netdev_nb);
+	rdma_link_unregister(&siw_link_ops);
+	ib_unregister_driver(RDMA_DRIVER_SIW);
+
+	siw_cm_exit();
+
+	siw_destroy_cpulist();
+
+	if (siw_crypto_shash)
+		crypto_free_shash(siw_crypto_shash);
+
+	pr_info("SoftiWARP detached\n");
+}
+
+module_init(siw_init_module);
+module_exit(siw_exit_module);
+
+MODULE_ALIAS_RDMA_LINK("siw");
diff --git a/drivers/infiniband/sw/siw/siw_mem.c b/drivers/infiniband/sw/siw/siw_mem.c
new file mode 100644
index 000000000000..67171c82b0c4
--- /dev/null
+++ b/drivers/infiniband/sw/siw/siw_mem.c
@@ -0,0 +1,460 @@
+// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+
+#include <linux/gfp.h>
+#include <rdma/ib_verbs.h>
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+#include <linux/sched/mm.h>
+#include <linux/resource.h>
+
+#include "siw.h"
+#include "siw_mem.h"
+
+/*
+ * Stag lookup is based on its index part only (24 bits).
+ * The code avoids special Stag of zero and tries to randomize
+ * STag values between 1 and SIW_STAG_MAX_INDEX.
+ */
+int siw_mem_add(struct siw_device *sdev, struct siw_mem *m)
+{
+	struct xa_limit limit = XA_LIMIT(1, 0x00ffffff);
+	u32 id, next;
+
+	get_random_bytes(&next, 4);
+	next &= 0x00ffffff;
+
+	if (xa_alloc_cyclic(&sdev->mem_xa, &id, m, limit, &next,
+	    GFP_KERNEL) < 0)
+		return -ENOMEM;
+
+	/* Set the STag index part */
+	m->stag = id << 8;
+
+	siw_dbg_mem(m, "new MEM object\n");
+
+	return 0;
+}
+
+/*
+ * siw_mem_id2obj()
+ *
+ * resolves memory from stag given by id. might be called from:
+ * o process context before sending out of sgl, or
+ * o in softirq when resolving target memory
+ */
+struct siw_mem *siw_mem_id2obj(struct siw_device *sdev, int stag_index)
+{
+	struct siw_mem *mem;
+
+	rcu_read_lock();
+	mem = xa_load(&sdev->mem_xa, stag_index);
+	if (likely(mem && kref_get_unless_zero(&mem->ref))) {
+		rcu_read_unlock();
+		return mem;
+	}
+	rcu_read_unlock();
+
+	return NULL;
+}
+
+static void siw_free_plist(struct siw_page_chunk *chunk, int num_pages,
+			   bool dirty)
+{
+	struct page **p = chunk->plist;
+
+	while (num_pages--) {
+		if (!PageDirty(*p) && dirty)
+			put_user_pages_dirty_lock(p, 1);
+		else
+			put_user_page(*p);
+		p++;
+	}
+}
+
+void siw_umem_release(struct siw_umem *umem, bool dirty)
+{
+	struct mm_struct *mm_s = umem->owning_mm;
+	int i, num_pages = umem->num_pages;
+
+	for (i = 0; num_pages; i++) {
+		int to_free = min_t(int, PAGES_PER_CHUNK, num_pages);
+
+		siw_free_plist(&umem->page_chunk[i], to_free,
+			       umem->writable && dirty);
+		kfree(umem->page_chunk[i].plist);
+		num_pages -= to_free;
+	}
+	atomic64_sub(umem->num_pages, &mm_s->pinned_vm);
+
+	mmdrop(mm_s);
+	kfree(umem->page_chunk);
+	kfree(umem);
+}
+
+int siw_mr_add_mem(struct siw_mr *mr, struct ib_pd *pd, void *mem_obj,
+		   u64 start, u64 len, int rights)
+{
+	struct siw_device *sdev = to_siw_dev(pd->device);
+	struct siw_mem *mem = kzalloc(sizeof(*mem), GFP_KERNEL);
+	struct xa_limit limit = XA_LIMIT(1, 0x00ffffff);
+	u32 id, next;
+
+	if (!mem)
+		return -ENOMEM;
+
+	mem->mem_obj = mem_obj;
+	mem->stag_valid = 0;
+	mem->sdev = sdev;
+	mem->va = start;
+	mem->len = len;
+	mem->pd = pd;
+	mem->perms = rights & IWARP_ACCESS_MASK;
+	kref_init(&mem->ref);
+
+	mr->mem = mem;
+
+	get_random_bytes(&next, 4);
+	next &= 0x00ffffff;
+
+	if (xa_alloc_cyclic(&sdev->mem_xa, &id, mem, limit, &next,
+	    GFP_KERNEL) < 0) {
+		kfree(mem);
+		return -ENOMEM;
+	}
+	/* Set the STag index part */
+	mem->stag = id << 8;
+	mr->base_mr.lkey = mr->base_mr.rkey = mem->stag;
+
+	return 0;
+}
+
+void siw_mr_drop_mem(struct siw_mr *mr)
+{
+	struct siw_mem *mem = mr->mem, *found;
+
+	mem->stag_valid = 0;
+
+	/* make STag invalid visible asap */
+	smp_mb();
+
+	found = xa_erase(&mem->sdev->mem_xa, mem->stag >> 8);
+	WARN_ON(found != mem);
+	siw_mem_put(mem);
+}
+
+void siw_free_mem(struct kref *ref)
+{
+	struct siw_mem *mem = container_of(ref, struct siw_mem, ref);
+
+	siw_dbg_mem(mem, "free mem, pbl: %s\n", mem->is_pbl ? "y" : "n");
+
+	if (!mem->is_mw && mem->mem_obj) {
+		if (mem->is_pbl == 0)
+			siw_umem_release(mem->umem, true);
+		else
+			kfree(mem->pbl);
+	}
+	kfree(mem);
+}
+
+/*
+ * siw_check_mem()
+ *
+ * Check protection domain, STAG state, access permissions and
+ * address range for memory object.
+ *
+ * @pd:		Protection Domain memory should belong to
+ * @mem:	memory to be checked
+ * @addr:	starting addr of mem
+ * @perms:	requested access permissions
+ * @len:	len of memory interval to be checked
+ *
+ */
+int siw_check_mem(struct ib_pd *pd, struct siw_mem *mem, u64 addr,
+		  enum ib_access_flags perms, int len)
+{
+	if (!mem->stag_valid) {
+		siw_dbg_pd(pd, "STag 0x%08x invalid\n", mem->stag);
+		return -E_STAG_INVALID;
+	}
+	if (mem->pd != pd) {
+		siw_dbg_pd(pd, "STag 0x%08x: PD mismatch\n", mem->stag);
+		return -E_PD_MISMATCH;
+	}
+	/*
+	 * check access permissions
+	 */
+	if ((mem->perms & perms) < perms) {
+		siw_dbg_pd(pd, "permissions 0x%08x < 0x%08x\n",
+			   mem->perms, perms);
+		return -E_ACCESS_PERM;
+	}
+	/*
+	 * Check if access falls into valid memory interval.
+	 */
+	if (addr < mem->va || addr + len > mem->va + mem->len) {
+		siw_dbg_pd(pd, "MEM interval len %d\n", len);
+		siw_dbg_pd(pd, "[0x%016llx, 0x%016llx] out of bounds\n",
+			   (unsigned long long)addr,
+			   (unsigned long long)(addr + len));
+		siw_dbg_pd(pd, "[0x%016llx, 0x%016llx] STag=0x%08x\n",
+			   (unsigned long long)mem->va,
+			   (unsigned long long)(mem->va + mem->len),
+			   mem->stag);
+
+		return -E_BASE_BOUNDS;
+	}
+	return E_ACCESS_OK;
+}
+
+/*
+ * siw_check_sge()
+ *
+ * Check SGE for access rights in given interval
+ *
+ * @pd:		Protection Domain memory should belong to
+ * @sge:	SGE to be checked
+ * @mem:	location of memory reference within array
+ * @perms:	requested access permissions
+ * @off:	starting offset in SGE
+ * @len:	len of memory interval to be checked
+ *
+ * NOTE: Function references SGE's memory object (mem->obj)
+ * if not yet done. New reference is kept if check went ok and
+ * released if check failed. If mem->obj is already valid, no new
+ * lookup is being done and mem is not released it check fails.
+ */
+int siw_check_sge(struct ib_pd *pd, struct siw_sge *sge, struct siw_mem *mem[],
+		  enum ib_access_flags perms, u32 off, int len)
+{
+	struct siw_device *sdev = to_siw_dev(pd->device);
+	struct siw_mem *new = NULL;
+	int rv = E_ACCESS_OK;
+
+	if (len + off > sge->length) {
+		rv = -E_BASE_BOUNDS;
+		goto fail;
+	}
+	if (*mem == NULL) {
+		new = siw_mem_id2obj(sdev, sge->lkey >> 8);
+		if (unlikely(!new)) {
+			siw_dbg_pd(pd, "STag unknown: 0x%08x\n", sge->lkey);
+			rv = -E_STAG_INVALID;
+			goto fail;
+		}
+		*mem = new;
+	}
+	/* Check if user re-registered with different STag key */
+	if (unlikely((*mem)->stag != sge->lkey)) {
+		siw_dbg_mem((*mem), "STag mismatch: 0x%08x\n", sge->lkey);
+		rv = -E_STAG_INVALID;
+		goto fail;
+	}
+	rv = siw_check_mem(pd, *mem, sge->laddr + off, perms, len);
+	if (unlikely(rv))
+		goto fail;
+
+	return 0;
+
+fail:
+	if (new) {
+		*mem = NULL;
+		siw_mem_put(new);
+	}
+	return rv;
+}
+
+void siw_wqe_put_mem(struct siw_wqe *wqe, enum siw_opcode op)
+{
+	switch (op) {
+	case SIW_OP_SEND:
+	case SIW_OP_WRITE:
+	case SIW_OP_SEND_WITH_IMM:
+	case SIW_OP_SEND_REMOTE_INV:
+	case SIW_OP_READ:
+	case SIW_OP_READ_LOCAL_INV:
+		if (!(wqe->sqe.flags & SIW_WQE_INLINE))
+			siw_unref_mem_sgl(wqe->mem, wqe->sqe.num_sge);
+		break;
+
+	case SIW_OP_RECEIVE:
+		siw_unref_mem_sgl(wqe->mem, wqe->rqe.num_sge);
+		break;
+
+	case SIW_OP_READ_RESPONSE:
+		siw_unref_mem_sgl(wqe->mem, 1);
+		break;
+
+	default:
+		/*
+		 * SIW_OP_INVAL_STAG and SIW_OP_REG_MR
+		 * do not hold memory references
+		 */
+		break;
+	}
+}
+
+int siw_invalidate_stag(struct ib_pd *pd, u32 stag)
+{
+	struct siw_device *sdev = to_siw_dev(pd->device);
+	struct siw_mem *mem = siw_mem_id2obj(sdev, stag >> 8);
+	int rv = 0;
+
+	if (unlikely(!mem)) {
+		siw_dbg_pd(pd, "STag 0x%08x unknown\n", stag);
+		return -EINVAL;
+	}
+	if (unlikely(mem->pd != pd)) {
+		siw_dbg_pd(pd, "PD mismatch for STag 0x%08x\n", stag);
+		rv = -EACCES;
+		goto out;
+	}
+	/*
+	 * Per RDMA verbs definition, an STag may already be in invalid
+	 * state if invalidation is requested. So no state check here.
+	 */
+	mem->stag_valid = 0;
+
+	siw_dbg_pd(pd, "STag 0x%08x now invalid\n", stag);
+out:
+	siw_mem_put(mem);
+	return rv;
+}
+
+/*
+ * Gets physical address backed by PBL element. Address is referenced
+ * by linear byte offset into list of variably sized PB elements.
+ * Optionally, provides remaining len within current element, and
+ * current PBL index for later resume at same element.
+ */
+u64 siw_pbl_get_buffer(struct siw_pbl *pbl, u64 off, int *len, int *idx)
+{
+	int i = idx ? *idx : 0;
+
+	while (i < pbl->num_buf) {
+		struct siw_pble *pble = &pbl->pbe[i];
+
+		if (pble->pbl_off + pble->size > off) {
+			u64 pble_off = off - pble->pbl_off;
+
+			if (len)
+				*len = pble->size - pble_off;
+			if (idx)
+				*idx = i;
+
+			return pble->addr + pble_off;
+		}
+		i++;
+	}
+	if (len)
+		*len = 0;
+	return 0;
+}
+
+struct siw_pbl *siw_pbl_alloc(u32 num_buf)
+{
+	struct siw_pbl *pbl;
+	int buf_size = sizeof(*pbl);
+
+	if (num_buf == 0)
+		return ERR_PTR(-EINVAL);
+
+	buf_size += ((num_buf - 1) * sizeof(struct siw_pble));
+
+	pbl = kzalloc(buf_size, GFP_KERNEL);
+	if (!pbl)
+		return ERR_PTR(-ENOMEM);
+
+	pbl->max_buf = num_buf;
+
+	return pbl;
+}
+
+struct siw_umem *siw_umem_get(u64 start, u64 len, bool writable)
+{
+	struct siw_umem *umem;
+	struct mm_struct *mm_s;
+	u64 first_page_va;
+	unsigned long mlock_limit;
+	unsigned int foll_flags = FOLL_WRITE;
+	int num_pages, num_chunks, i, rv = 0;
+
+	if (!can_do_mlock())
+		return ERR_PTR(-EPERM);
+
+	if (!len)
+		return ERR_PTR(-EINVAL);
+
+	first_page_va = start & PAGE_MASK;
+	num_pages = PAGE_ALIGN(start + len - first_page_va) >> PAGE_SHIFT;
+	num_chunks = (num_pages >> CHUNK_SHIFT) + 1;
+
+	umem = kzalloc(sizeof(*umem), GFP_KERNEL);
+	if (!umem)
+		return ERR_PTR(-ENOMEM);
+
+	mm_s = current->mm;
+	umem->owning_mm = mm_s;
+	umem->writable = writable;
+
+	mmgrab(mm_s);
+
+	if (!writable)
+		foll_flags |= FOLL_FORCE;
+
+	down_read(&mm_s->mmap_sem);
+
+	mlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
+
+	if (num_pages + atomic64_read(&mm_s->pinned_vm) > mlock_limit) {
+		rv = -ENOMEM;
+		goto out_sem_up;
+	}
+	umem->fp_addr = first_page_va;
+
+	umem->page_chunk =
+		kcalloc(num_chunks, sizeof(struct siw_page_chunk), GFP_KERNEL);
+	if (!umem->page_chunk) {
+		rv = -ENOMEM;
+		goto out_sem_up;
+	}
+	for (i = 0; num_pages; i++) {
+		int got, nents = min_t(int, num_pages, PAGES_PER_CHUNK);
+
+		umem->page_chunk[i].plist =
+			kcalloc(nents, sizeof(struct page *), GFP_KERNEL);
+		if (!umem->page_chunk[i].plist) {
+			rv = -ENOMEM;
+			goto out_sem_up;
+		}
+		got = 0;
+		while (nents) {
+			struct page **plist = &umem->page_chunk[i].plist[got];
+
+			rv = get_user_pages(first_page_va, nents,
+					    foll_flags | FOLL_LONGTERM,
+					    plist, NULL);
+			if (rv < 0)
+				goto out_sem_up;
+
+			umem->num_pages += rv;
+			atomic64_add(rv, &mm_s->pinned_vm);
+			first_page_va += rv * PAGE_SIZE;
+			nents -= rv;
+			got += rv;
+		}
+		num_pages -= got;
+	}
+out_sem_up:
+	up_read(&mm_s->mmap_sem);
+
+	if (rv > 0)
+		return umem;
+
+	siw_umem_release(umem, false);
+
+	return ERR_PTR(rv);
+}
diff --git a/drivers/infiniband/sw/siw/siw_mem.h b/drivers/infiniband/sw/siw/siw_mem.h
new file mode 100644
index 000000000000..f43daf280891
--- /dev/null
+++ b/drivers/infiniband/sw/siw/siw_mem.h
@@ -0,0 +1,74 @@
+/* SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause */
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+
+#ifndef _SIW_MEM_H
+#define _SIW_MEM_H
+
+struct siw_umem *siw_umem_get(u64 start, u64 len, bool writable);
+void siw_umem_release(struct siw_umem *umem, bool dirty);
+struct siw_pbl *siw_pbl_alloc(u32 num_buf);
+u64 siw_pbl_get_buffer(struct siw_pbl *pbl, u64 off, int *len, int *idx);
+struct siw_mem *siw_mem_id2obj(struct siw_device *sdev, int stag_index);
+int siw_mem_add(struct siw_device *sdev, struct siw_mem *m);
+int siw_invalidate_stag(struct ib_pd *pd, u32 stag);
+int siw_check_mem(struct ib_pd *pd, struct siw_mem *mem, u64 addr,
+		  enum ib_access_flags perms, int len);
+int siw_check_sge(struct ib_pd *pd, struct siw_sge *sge,
+		  struct siw_mem *mem[], enum ib_access_flags perms,
+		  u32 off, int len);
+void siw_wqe_put_mem(struct siw_wqe *wqe, enum siw_opcode op);
+int siw_mr_add_mem(struct siw_mr *mr, struct ib_pd *pd, void *mem_obj,
+		   u64 start, u64 len, int rights);
+void siw_mr_drop_mem(struct siw_mr *mr);
+void siw_free_mem(struct kref *ref);
+
+static inline void siw_mem_put(struct siw_mem *mem)
+{
+	kref_put(&mem->ref, siw_free_mem);
+}
+
+static inline struct siw_mr *siw_mem2mr(struct siw_mem *m)
+{
+	return container_of(m, struct siw_mr, mem);
+}
+
+static inline void siw_unref_mem_sgl(struct siw_mem **mem, unsigned int num_sge)
+{
+	while (num_sge) {
+		if (*mem == NULL)
+			break;
+
+		siw_mem_put(*mem);
+		*mem = NULL;
+		mem++;
+		num_sge--;
+	}
+}
+
+#define CHUNK_SHIFT 9 /* sets number of pages per chunk */
+#define PAGES_PER_CHUNK (_AC(1, UL) << CHUNK_SHIFT)
+#define CHUNK_MASK (~(PAGES_PER_CHUNK - 1))
+#define PAGE_CHUNK_SIZE (PAGES_PER_CHUNK * sizeof(struct page *))
+
+/*
+ * siw_get_upage()
+ *
+ * Get page pointer for address on given umem.
+ *
+ * @umem: two dimensional list of page pointers
+ * @addr: user virtual address
+ */
+static inline struct page *siw_get_upage(struct siw_umem *umem, u64 addr)
+{
+	unsigned int page_idx = (addr - umem->fp_addr) >> PAGE_SHIFT,
+		     chunk_idx = page_idx >> CHUNK_SHIFT,
+		     page_in_chunk = page_idx & ~CHUNK_MASK;
+
+	if (likely(page_idx < umem->num_pages))
+		return umem->page_chunk[chunk_idx].plist[page_in_chunk];
+
+	return NULL;
+}
+#endif
diff --git a/drivers/infiniband/sw/siw/siw_qp.c b/drivers/infiniband/sw/siw/siw_qp.c
new file mode 100644
index 000000000000..11383d9f95ef
--- /dev/null
+++ b/drivers/infiniband/sw/siw/siw_qp.c
@@ -0,0 +1,1322 @@
+// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/net.h>
+#include <linux/scatterlist.h>
+#include <linux/llist.h>
+#include <asm/barrier.h>
+#include <net/tcp.h>
+
+#include "siw.h"
+#include "siw_verbs.h"
+#include "siw_mem.h"
+
+static char siw_qp_state_to_string[SIW_QP_STATE_COUNT][sizeof "TERMINATE"] = {
+	[SIW_QP_STATE_IDLE] = "IDLE",
+	[SIW_QP_STATE_RTR] = "RTR",
+	[SIW_QP_STATE_RTS] = "RTS",
+	[SIW_QP_STATE_CLOSING] = "CLOSING",
+	[SIW_QP_STATE_TERMINATE] = "TERMINATE",
+	[SIW_QP_STATE_ERROR] = "ERROR"
+};
+
+/*
+ * iWARP (RDMAP, DDP and MPA) parameters as well as Softiwarp settings on a
+ * per-RDMAP message basis. Please keep order of initializer. All MPA len
+ * is initialized to minimum packet size.
+ */
+struct iwarp_msg_info iwarp_pktinfo[RDMAP_TERMINATE + 1] = {
+	{ /* RDMAP_RDMA_WRITE */
+	  .hdr_len = sizeof(struct iwarp_rdma_write),
+	  .ctrl.mpa_len = htons(sizeof(struct iwarp_rdma_write) - 2),
+	  .ctrl.ddp_rdmap_ctrl = DDP_FLAG_TAGGED | DDP_FLAG_LAST |
+				 cpu_to_be16(DDP_VERSION << 8) |
+				 cpu_to_be16(RDMAP_VERSION << 6) |
+				 cpu_to_be16(RDMAP_RDMA_WRITE),
+	  .rx_data = siw_proc_write },
+	{ /* RDMAP_RDMA_READ_REQ */
+	  .hdr_len = sizeof(struct iwarp_rdma_rreq),
+	  .ctrl.mpa_len = htons(sizeof(struct iwarp_rdma_rreq) - 2),
+	  .ctrl.ddp_rdmap_ctrl = DDP_FLAG_LAST | cpu_to_be16(DDP_VERSION << 8) |
+				 cpu_to_be16(RDMAP_VERSION << 6) |
+				 cpu_to_be16(RDMAP_RDMA_READ_REQ),
+	  .rx_data = siw_proc_rreq },
+	{ /* RDMAP_RDMA_READ_RESP */
+	  .hdr_len = sizeof(struct iwarp_rdma_rresp),
+	  .ctrl.mpa_len = htons(sizeof(struct iwarp_rdma_rresp) - 2),
+	  .ctrl.ddp_rdmap_ctrl = DDP_FLAG_TAGGED | DDP_FLAG_LAST |
+				 cpu_to_be16(DDP_VERSION << 8) |
+				 cpu_to_be16(RDMAP_VERSION << 6) |
+				 cpu_to_be16(RDMAP_RDMA_READ_RESP),
+	  .rx_data = siw_proc_rresp },
+	{ /* RDMAP_SEND */
+	  .hdr_len = sizeof(struct iwarp_send),
+	  .ctrl.mpa_len = htons(sizeof(struct iwarp_send) - 2),
+	  .ctrl.ddp_rdmap_ctrl = DDP_FLAG_LAST | cpu_to_be16(DDP_VERSION << 8) |
+				 cpu_to_be16(RDMAP_VERSION << 6) |
+				 cpu_to_be16(RDMAP_SEND),
+	  .rx_data = siw_proc_send },
+	{ /* RDMAP_SEND_INVAL */
+	  .hdr_len = sizeof(struct iwarp_send_inv),
+	  .ctrl.mpa_len = htons(sizeof(struct iwarp_send_inv) - 2),
+	  .ctrl.ddp_rdmap_ctrl = DDP_FLAG_LAST | cpu_to_be16(DDP_VERSION << 8) |
+				 cpu_to_be16(RDMAP_VERSION << 6) |
+				 cpu_to_be16(RDMAP_SEND_INVAL),
+	  .rx_data = siw_proc_send },
+	{ /* RDMAP_SEND_SE */
+	  .hdr_len = sizeof(struct iwarp_send),
+	  .ctrl.mpa_len = htons(sizeof(struct iwarp_send) - 2),
+	  .ctrl.ddp_rdmap_ctrl = DDP_FLAG_LAST | cpu_to_be16(DDP_VERSION << 8) |
+				 cpu_to_be16(RDMAP_VERSION << 6) |
+				 cpu_to_be16(RDMAP_SEND_SE),
+	  .rx_data = siw_proc_send },
+	{ /* RDMAP_SEND_SE_INVAL */
+	  .hdr_len = sizeof(struct iwarp_send_inv),
+	  .ctrl.mpa_len = htons(sizeof(struct iwarp_send_inv) - 2),
+	  .ctrl.ddp_rdmap_ctrl = DDP_FLAG_LAST | cpu_to_be16(DDP_VERSION << 8) |
+				 cpu_to_be16(RDMAP_VERSION << 6) |
+				 cpu_to_be16(RDMAP_SEND_SE_INVAL),
+	  .rx_data = siw_proc_send },
+	{ /* RDMAP_TERMINATE */
+	  .hdr_len = sizeof(struct iwarp_terminate),
+	  .ctrl.mpa_len = htons(sizeof(struct iwarp_terminate) - 2),
+	  .ctrl.ddp_rdmap_ctrl = DDP_FLAG_LAST | cpu_to_be16(DDP_VERSION << 8) |
+				 cpu_to_be16(RDMAP_VERSION << 6) |
+				 cpu_to_be16(RDMAP_TERMINATE),
+	  .rx_data = siw_proc_terminate }
+};
+
+void siw_qp_llp_data_ready(struct sock *sk)
+{
+	struct siw_qp *qp;
+
+	read_lock(&sk->sk_callback_lock);
+
+	if (unlikely(!sk->sk_user_data || !sk_to_qp(sk)))
+		goto done;
+
+	qp = sk_to_qp(sk);
+
+	if (likely(!qp->rx_stream.rx_suspend &&
+		   down_read_trylock(&qp->state_lock))) {
+		read_descriptor_t rd_desc = { .arg.data = qp, .count = 1 };
+
+		if (likely(qp->attrs.state == SIW_QP_STATE_RTS))
+			/*
+			 * Implements data receive operation during
+			 * socket callback. TCP gracefully catches
+			 * the case where there is nothing to receive
+			 * (not calling siw_tcp_rx_data() then).
+			 */
+			tcp_read_sock(sk, &rd_desc, siw_tcp_rx_data);
+
+		up_read(&qp->state_lock);
+	} else {
+		siw_dbg_qp(qp, "unable to process RX, suspend: %d\n",
+			   qp->rx_stream.rx_suspend);
+	}
+done:
+	read_unlock(&sk->sk_callback_lock);
+}
+
+void siw_qp_llp_close(struct siw_qp *qp)
+{
+	siw_dbg_qp(qp, "enter llp close, state = %s\n",
+		   siw_qp_state_to_string[qp->attrs.state]);
+
+	down_write(&qp->state_lock);
+
+	qp->rx_stream.rx_suspend = 1;
+	qp->tx_ctx.tx_suspend = 1;
+	qp->attrs.sk = NULL;
+
+	switch (qp->attrs.state) {
+	case SIW_QP_STATE_RTS:
+	case SIW_QP_STATE_RTR:
+	case SIW_QP_STATE_IDLE:
+	case SIW_QP_STATE_TERMINATE:
+		qp->attrs.state = SIW_QP_STATE_ERROR;
+		break;
+	/*
+	 * SIW_QP_STATE_CLOSING:
+	 *
+	 * This is a forced close. shall the QP be moved to
+	 * ERROR or IDLE ?
+	 */
+	case SIW_QP_STATE_CLOSING:
+		if (tx_wqe(qp)->wr_status == SIW_WR_IDLE)
+			qp->attrs.state = SIW_QP_STATE_ERROR;
+		else
+			qp->attrs.state = SIW_QP_STATE_IDLE;
+		break;
+
+	default:
+		siw_dbg_qp(qp, "llp close: no state transition needed: %s\n",
+			   siw_qp_state_to_string[qp->attrs.state]);
+		break;
+	}
+	siw_sq_flush(qp);
+	siw_rq_flush(qp);
+
+	/*
+	 * Dereference closing CEP
+	 */
+	if (qp->cep) {
+		siw_cep_put(qp->cep);
+		qp->cep = NULL;
+	}
+
+	up_write(&qp->state_lock);
+
+	siw_dbg_qp(qp, "llp close exit: state %s\n",
+		   siw_qp_state_to_string[qp->attrs.state]);
+}
+
+/*
+ * socket callback routine informing about newly available send space.
+ * Function schedules SQ work for processing SQ items.
+ */
+void siw_qp_llp_write_space(struct sock *sk)
+{
+	struct siw_cep *cep = sk_to_cep(sk);
+
+	cep->sk_write_space(sk);
+
+	if (!test_bit(SOCK_NOSPACE, &sk->sk_socket->flags))
+		(void)siw_sq_start(cep->qp);
+}
+
+static int siw_qp_readq_init(struct siw_qp *qp, int irq_size, int orq_size)
+{
+	irq_size = roundup_pow_of_two(irq_size);
+	orq_size = roundup_pow_of_two(orq_size);
+
+	qp->attrs.irq_size = irq_size;
+	qp->attrs.orq_size = orq_size;
+
+	qp->irq = vzalloc(irq_size * sizeof(struct siw_sqe));
+	if (!qp->irq) {
+		siw_dbg_qp(qp, "irq malloc for %d failed\n", irq_size);
+		qp->attrs.irq_size = 0;
+		return -ENOMEM;
+	}
+	qp->orq = vzalloc(orq_size * sizeof(struct siw_sqe));
+	if (!qp->orq) {
+		siw_dbg_qp(qp, "orq malloc for %d failed\n", orq_size);
+		qp->attrs.orq_size = 0;
+		qp->attrs.irq_size = 0;
+		vfree(qp->irq);
+		return -ENOMEM;
+	}
+	siw_dbg_qp(qp, "ORD %d, IRD %d\n", orq_size, irq_size);
+	return 0;
+}
+
+static int siw_qp_enable_crc(struct siw_qp *qp)
+{
+	struct siw_rx_stream *c_rx = &qp->rx_stream;
+	struct siw_iwarp_tx *c_tx = &qp->tx_ctx;
+	int size = crypto_shash_descsize(siw_crypto_shash) +
+			sizeof(struct shash_desc);
+
+	if (siw_crypto_shash == NULL)
+		return -ENOENT;
+
+	c_tx->mpa_crc_hd = kzalloc(size, GFP_KERNEL);
+	c_rx->mpa_crc_hd = kzalloc(size, GFP_KERNEL);
+	if (!c_tx->mpa_crc_hd || !c_rx->mpa_crc_hd) {
+		kfree(c_tx->mpa_crc_hd);
+		kfree(c_rx->mpa_crc_hd);
+		c_tx->mpa_crc_hd = NULL;
+		c_rx->mpa_crc_hd = NULL;
+		return -ENOMEM;
+	}
+	c_tx->mpa_crc_hd->tfm = siw_crypto_shash;
+	c_rx->mpa_crc_hd->tfm = siw_crypto_shash;
+
+	return 0;
+}
+
+/*
+ * Send a non signalled READ or WRITE to peer side as negotiated
+ * with MPAv2 P2P setup protocol. The work request is only created
+ * as a current active WR and does not consume Send Queue space.
+ *
+ * Caller must hold QP state lock.
+ */
+int siw_qp_mpa_rts(struct siw_qp *qp, enum mpa_v2_ctrl ctrl)
+{
+	struct siw_wqe *wqe = tx_wqe(qp);
+	unsigned long flags;
+	int rv = 0;
+
+	spin_lock_irqsave(&qp->sq_lock, flags);
+
+	if (unlikely(wqe->wr_status != SIW_WR_IDLE)) {
+		spin_unlock_irqrestore(&qp->sq_lock, flags);
+		return -EIO;
+	}
+	memset(wqe->mem, 0, sizeof(*wqe->mem) * SIW_MAX_SGE);
+
+	wqe->wr_status = SIW_WR_QUEUED;
+	wqe->sqe.flags = 0;
+	wqe->sqe.num_sge = 1;
+	wqe->sqe.sge[0].length = 0;
+	wqe->sqe.sge[0].laddr = 0;
+	wqe->sqe.sge[0].lkey = 0;
+	/*
+	 * While it must not be checked for inbound zero length
+	 * READ/WRITE, some HW may treat STag 0 special.
+	 */
+	wqe->sqe.rkey = 1;
+	wqe->sqe.raddr = 0;
+	wqe->processed = 0;
+
+	if (ctrl & MPA_V2_RDMA_WRITE_RTR)
+		wqe->sqe.opcode = SIW_OP_WRITE;
+	else if (ctrl & MPA_V2_RDMA_READ_RTR) {
+		struct siw_sqe *rreq;
+
+		wqe->sqe.opcode = SIW_OP_READ;
+
+		spin_lock(&qp->orq_lock);
+
+		rreq = orq_get_free(qp);
+		if (rreq) {
+			siw_read_to_orq(rreq, &wqe->sqe);
+			qp->orq_put++;
+		} else
+			rv = -EIO;
+
+		spin_unlock(&qp->orq_lock);
+	} else
+		rv = -EINVAL;
+
+	if (rv)
+		wqe->wr_status = SIW_WR_IDLE;
+
+	spin_unlock_irqrestore(&qp->sq_lock, flags);
+
+	if (!rv)
+		rv = siw_sq_start(qp);
+
+	return rv;
+}
+
+/*
+ * Map memory access error to DDP tagged error
+ */
+enum ddp_ecode siw_tagged_error(enum siw_access_state state)
+{
+	switch (state) {
+	case E_STAG_INVALID:
+		return DDP_ECODE_T_INVALID_STAG;
+	case E_BASE_BOUNDS:
+		return DDP_ECODE_T_BASE_BOUNDS;
+	case E_PD_MISMATCH:
+		return DDP_ECODE_T_STAG_NOT_ASSOC;
+	case E_ACCESS_PERM:
+		/*
+		 * RFC 5041 (DDP) lacks an ecode for insufficient access
+		 * permissions. 'Invalid STag' seem to be the closest
+		 * match though.
+		 */
+		return DDP_ECODE_T_INVALID_STAG;
+	default:
+		WARN_ON(1);
+		return DDP_ECODE_T_INVALID_STAG;
+	}
+}
+
+/*
+ * Map memory access error to RDMAP protection error
+ */
+enum rdmap_ecode siw_rdmap_error(enum siw_access_state state)
+{
+	switch (state) {
+	case E_STAG_INVALID:
+		return RDMAP_ECODE_INVALID_STAG;
+	case E_BASE_BOUNDS:
+		return RDMAP_ECODE_BASE_BOUNDS;
+	case E_PD_MISMATCH:
+		return RDMAP_ECODE_STAG_NOT_ASSOC;
+	case E_ACCESS_PERM:
+		return RDMAP_ECODE_ACCESS_RIGHTS;
+	default:
+		return RDMAP_ECODE_UNSPECIFIED;
+	}
+}
+
+void siw_init_terminate(struct siw_qp *qp, enum term_elayer layer, u8 etype,
+			u8 ecode, int in_tx)
+{
+	if (!qp->term_info.valid) {
+		memset(&qp->term_info, 0, sizeof(qp->term_info));
+		qp->term_info.layer = layer;
+		qp->term_info.etype = etype;
+		qp->term_info.ecode = ecode;
+		qp->term_info.in_tx = in_tx;
+		qp->term_info.valid = 1;
+	}
+	siw_dbg_qp(qp, "init TERM: layer %d, type %d, code %d, in tx %s\n",
+		   layer, etype, ecode, in_tx ? "yes" : "no");
+}
+
+/*
+ * Send a TERMINATE message, as defined in RFC's 5040/5041/5044/6581.
+ * Sending TERMINATE messages is best effort - such messages
+ * can only be send if the QP is still connected and it does
+ * not have another outbound message in-progress, i.e. the
+ * TERMINATE message must not interfer with an incomplete current
+ * transmit operation.
+ */
+void siw_send_terminate(struct siw_qp *qp)
+{
+	struct kvec iov[3];
+	struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_EOR };
+	struct iwarp_terminate *term = NULL;
+	union iwarp_hdr *err_hdr = NULL;
+	struct socket *s = qp->attrs.sk;
+	struct siw_rx_stream *srx = &qp->rx_stream;
+	union iwarp_hdr *rx_hdr = &srx->hdr;
+	u32 crc = 0;
+	int num_frags, len_terminate, rv;
+
+	if (!qp->term_info.valid)
+		return;
+
+	qp->term_info.valid = 0;
+
+	if (tx_wqe(qp)->wr_status == SIW_WR_INPROGRESS) {
+		siw_dbg_qp(qp, "cannot send TERMINATE: op %d in progress\n",
+			   tx_type(tx_wqe(qp)));
+		return;
+	}
+	if (!s && qp->cep)
+		/* QP not yet in RTS. Take socket from connection end point */
+		s = qp->cep->sock;
+
+	if (!s) {
+		siw_dbg_qp(qp, "cannot send TERMINATE: not connected\n");
+		return;
+	}
+
+	term = kzalloc(sizeof(*term), GFP_KERNEL);
+	if (!term)
+		return;
+
+	term->ddp_qn = cpu_to_be32(RDMAP_UNTAGGED_QN_TERMINATE);
+	term->ddp_mo = 0;
+	term->ddp_msn = cpu_to_be32(1);
+
+	iov[0].iov_base = term;
+	iov[0].iov_len = sizeof(*term);
+
+	if ((qp->term_info.layer == TERM_ERROR_LAYER_DDP) ||
+	    ((qp->term_info.layer == TERM_ERROR_LAYER_RDMAP) &&
+	     (qp->term_info.etype != RDMAP_ETYPE_CATASTROPHIC))) {
+		err_hdr = kzalloc(sizeof(*err_hdr), GFP_KERNEL);
+		if (!err_hdr) {
+			kfree(term);
+			return;
+		}
+	}
+	memcpy(&term->ctrl, &iwarp_pktinfo[RDMAP_TERMINATE].ctrl,
+	       sizeof(struct iwarp_ctrl));
+
+	__rdmap_term_set_layer(term, qp->term_info.layer);
+	__rdmap_term_set_etype(term, qp->term_info.etype);
+	__rdmap_term_set_ecode(term, qp->term_info.ecode);
+
+	switch (qp->term_info.layer) {
+	case TERM_ERROR_LAYER_RDMAP:
+		if (qp->term_info.etype == RDMAP_ETYPE_CATASTROPHIC)
+			/* No additional DDP/RDMAP header to be included */
+			break;
+
+		if (qp->term_info.etype == RDMAP_ETYPE_REMOTE_PROTECTION) {
+			/*
+			 * Complete RDMAP frame will get attached, and
+			 * DDP segment length is valid
+			 */
+			term->flag_m = 1;
+			term->flag_d = 1;
+			term->flag_r = 1;
+
+			if (qp->term_info.in_tx) {
+				struct iwarp_rdma_rreq *rreq;
+				struct siw_wqe *wqe = tx_wqe(qp);
+
+				/* Inbound RREQ error, detected during
+				 * RRESP creation. Take state from
+				 * current TX work queue element to
+				 * reconstruct peers RREQ.
+				 */
+				rreq = (struct iwarp_rdma_rreq *)err_hdr;
+
+				memcpy(&rreq->ctrl,
+				       &iwarp_pktinfo[RDMAP_RDMA_READ_REQ].ctrl,
+				       sizeof(struct iwarp_ctrl));
+
+				rreq->rsvd = 0;
+				rreq->ddp_qn =
+					htonl(RDMAP_UNTAGGED_QN_RDMA_READ);
+
+				/* Provide RREQ's MSN as kept aside */
+				rreq->ddp_msn = htonl(wqe->sqe.sge[0].length);
+
+				rreq->ddp_mo = htonl(wqe->processed);
+				rreq->sink_stag = htonl(wqe->sqe.rkey);
+				rreq->sink_to = cpu_to_be64(wqe->sqe.raddr);
+				rreq->read_size = htonl(wqe->sqe.sge[0].length);
+				rreq->source_stag = htonl(wqe->sqe.sge[0].lkey);
+				rreq->source_to =
+					cpu_to_be64(wqe->sqe.sge[0].laddr);
+
+				iov[1].iov_base = rreq;
+				iov[1].iov_len = sizeof(*rreq);
+
+				rx_hdr = (union iwarp_hdr *)rreq;
+			} else {
+				/* Take RDMAP/DDP information from
+				 * current (failed) inbound frame.
+				 */
+				iov[1].iov_base = rx_hdr;
+
+				if (__rdmap_get_opcode(&rx_hdr->ctrl) ==
+				    RDMAP_RDMA_READ_REQ)
+					iov[1].iov_len =
+						sizeof(struct iwarp_rdma_rreq);
+				else /* SEND type */
+					iov[1].iov_len =
+						sizeof(struct iwarp_send);
+			}
+		} else {
+			/* Do not report DDP hdr information if packet
+			 * layout is unknown
+			 */
+			if ((qp->term_info.ecode == RDMAP_ECODE_VERSION) ||
+			    (qp->term_info.ecode == RDMAP_ECODE_OPCODE))
+				break;
+
+			iov[1].iov_base = rx_hdr;
+
+			/* Only DDP frame will get attached */
+			if (rx_hdr->ctrl.ddp_rdmap_ctrl & DDP_FLAG_TAGGED)
+				iov[1].iov_len =
+					sizeof(struct iwarp_rdma_write);
+			else
+				iov[1].iov_len = sizeof(struct iwarp_send);
+
+			term->flag_m = 1;
+			term->flag_d = 1;
+		}
+		term->ctrl.mpa_len = cpu_to_be16(iov[1].iov_len);
+		break;
+
+	case TERM_ERROR_LAYER_DDP:
+		/* Report error encountered while DDP processing.
+		 * This can only happen as a result of inbound
+		 * DDP processing
+		 */
+
+		/* Do not report DDP hdr information if packet
+		 * layout is unknown
+		 */
+		if (((qp->term_info.etype == DDP_ETYPE_TAGGED_BUF) &&
+		     (qp->term_info.ecode == DDP_ECODE_T_VERSION)) ||
+		    ((qp->term_info.etype == DDP_ETYPE_UNTAGGED_BUF) &&
+		     (qp->term_info.ecode == DDP_ECODE_UT_VERSION)))
+			break;
+
+		iov[1].iov_base = rx_hdr;
+
+		if (rx_hdr->ctrl.ddp_rdmap_ctrl & DDP_FLAG_TAGGED)
+			iov[1].iov_len = sizeof(struct iwarp_ctrl_tagged);
+		else
+			iov[1].iov_len = sizeof(struct iwarp_ctrl_untagged);
+
+		term->flag_m = 1;
+		term->flag_d = 1;
+		break;
+
+	default:
+		break;
+	}
+	if (term->flag_m || term->flag_d || term->flag_r) {
+		iov[2].iov_base = &crc;
+		iov[2].iov_len = sizeof(crc);
+		len_terminate = sizeof(*term) + iov[1].iov_len + MPA_CRC_SIZE;
+		num_frags = 3;
+	} else {
+		iov[1].iov_base = &crc;
+		iov[1].iov_len = sizeof(crc);
+		len_terminate = sizeof(*term) + MPA_CRC_SIZE;
+		num_frags = 2;
+	}
+
+	/* Adjust DDP Segment Length parameter, if valid */
+	if (term->flag_m) {
+		u32 real_ddp_len = be16_to_cpu(rx_hdr->ctrl.mpa_len);
+		enum rdma_opcode op = __rdmap_get_opcode(&rx_hdr->ctrl);
+
+		real_ddp_len -= iwarp_pktinfo[op].hdr_len - MPA_HDR_SIZE;
+		rx_hdr->ctrl.mpa_len = cpu_to_be16(real_ddp_len);
+	}
+
+	term->ctrl.mpa_len =
+		cpu_to_be16(len_terminate - (MPA_HDR_SIZE + MPA_CRC_SIZE));
+	if (qp->tx_ctx.mpa_crc_hd) {
+		crypto_shash_init(qp->tx_ctx.mpa_crc_hd);
+		if (crypto_shash_update(qp->tx_ctx.mpa_crc_hd,
+					(u8 *)iov[0].iov_base,
+					iov[0].iov_len))
+			goto out;
+
+		if (num_frags == 3) {
+			if (crypto_shash_update(qp->tx_ctx.mpa_crc_hd,
+						(u8 *)iov[1].iov_base,
+						iov[1].iov_len))
+				goto out;
+		}
+		crypto_shash_final(qp->tx_ctx.mpa_crc_hd, (u8 *)&crc);
+	}
+
+	rv = kernel_sendmsg(s, &msg, iov, num_frags, len_terminate);
+	siw_dbg_qp(qp, "sent TERM: %s, layer %d, type %d, code %d (%d bytes)\n",
+		   rv == len_terminate ? "success" : "failure",
+		   __rdmap_term_layer(term), __rdmap_term_etype(term),
+		   __rdmap_term_ecode(term), rv);
+out:
+	kfree(term);
+	kfree(err_hdr);
+}
+
+/*
+ * Handle all attrs other than state
+ */
+static void siw_qp_modify_nonstate(struct siw_qp *qp,
+				   struct siw_qp_attrs *attrs,
+				   enum siw_qp_attr_mask mask)
+{
+	if (mask & SIW_QP_ATTR_ACCESS_FLAGS) {
+		if (attrs->flags & SIW_RDMA_BIND_ENABLED)
+			qp->attrs.flags |= SIW_RDMA_BIND_ENABLED;
+		else
+			qp->attrs.flags &= ~SIW_RDMA_BIND_ENABLED;
+
+		if (attrs->flags & SIW_RDMA_WRITE_ENABLED)
+			qp->attrs.flags |= SIW_RDMA_WRITE_ENABLED;
+		else
+			qp->attrs.flags &= ~SIW_RDMA_WRITE_ENABLED;
+
+		if (attrs->flags & SIW_RDMA_READ_ENABLED)
+			qp->attrs.flags |= SIW_RDMA_READ_ENABLED;
+		else
+			qp->attrs.flags &= ~SIW_RDMA_READ_ENABLED;
+	}
+}
+
+static int siw_qp_nextstate_from_idle(struct siw_qp *qp,
+				      struct siw_qp_attrs *attrs,
+				      enum siw_qp_attr_mask mask)
+{
+	int rv = 0;
+
+	switch (attrs->state) {
+	case SIW_QP_STATE_RTS:
+		if (attrs->flags & SIW_MPA_CRC) {
+			rv = siw_qp_enable_crc(qp);
+			if (rv)
+				break;
+		}
+		if (!(mask & SIW_QP_ATTR_LLP_HANDLE)) {
+			siw_dbg_qp(qp, "no socket\n");
+			rv = -EINVAL;
+			break;
+		}
+		if (!(mask & SIW_QP_ATTR_MPA)) {
+			siw_dbg_qp(qp, "no MPA\n");
+			rv = -EINVAL;
+			break;
+		}
+		/*
+		 * Initialize iWARP TX state
+		 */
+		qp->tx_ctx.ddp_msn[RDMAP_UNTAGGED_QN_SEND] = 0;
+		qp->tx_ctx.ddp_msn[RDMAP_UNTAGGED_QN_RDMA_READ] = 0;
+		qp->tx_ctx.ddp_msn[RDMAP_UNTAGGED_QN_TERMINATE] = 0;
+
+		/*
+		 * Initialize iWARP RX state
+		 */
+		qp->rx_stream.ddp_msn[RDMAP_UNTAGGED_QN_SEND] = 1;
+		qp->rx_stream.ddp_msn[RDMAP_UNTAGGED_QN_RDMA_READ] = 1;
+		qp->rx_stream.ddp_msn[RDMAP_UNTAGGED_QN_TERMINATE] = 1;
+
+		/*
+		 * init IRD free queue, caller has already checked
+		 * limits.
+		 */
+		rv = siw_qp_readq_init(qp, attrs->irq_size,
+				       attrs->orq_size);
+		if (rv)
+			break;
+
+		qp->attrs.sk = attrs->sk;
+		qp->attrs.state = SIW_QP_STATE_RTS;
+
+		siw_dbg_qp(qp, "enter RTS: crc=%s, ord=%u, ird=%u\n",
+			   attrs->flags & SIW_MPA_CRC ? "y" : "n",
+			   qp->attrs.orq_size, qp->attrs.irq_size);
+		break;
+
+	case SIW_QP_STATE_ERROR:
+		siw_rq_flush(qp);
+		qp->attrs.state = SIW_QP_STATE_ERROR;
+		if (qp->cep) {
+			siw_cep_put(qp->cep);
+			qp->cep = NULL;
+		}
+		break;
+
+	default:
+		break;
+	}
+	return rv;
+}
+
+static int siw_qp_nextstate_from_rts(struct siw_qp *qp,
+				     struct siw_qp_attrs *attrs)
+{
+	int drop_conn = 0;
+
+	switch (attrs->state) {
+	case SIW_QP_STATE_CLOSING:
+		/*
+		 * Verbs: move to IDLE if SQ and ORQ are empty.
+		 * Move to ERROR otherwise. But first of all we must
+		 * close the connection. So we keep CLOSING or ERROR
+		 * as a transient state, schedule connection drop work
+		 * and wait for the socket state change upcall to
+		 * come back closed.
+		 */
+		if (tx_wqe(qp)->wr_status == SIW_WR_IDLE) {
+			qp->attrs.state = SIW_QP_STATE_CLOSING;
+		} else {
+			qp->attrs.state = SIW_QP_STATE_ERROR;
+			siw_sq_flush(qp);
+		}
+		siw_rq_flush(qp);
+
+		drop_conn = 1;
+		break;
+
+	case SIW_QP_STATE_TERMINATE:
+		qp->attrs.state = SIW_QP_STATE_TERMINATE;
+
+		siw_init_terminate(qp, TERM_ERROR_LAYER_RDMAP,
+				   RDMAP_ETYPE_CATASTROPHIC,
+				   RDMAP_ECODE_UNSPECIFIED, 1);
+		drop_conn = 1;
+		break;
+
+	case SIW_QP_STATE_ERROR:
+		/*
+		 * This is an emergency close.
+		 *
+		 * Any in progress transmit operation will get
+		 * cancelled.
+		 * This will likely result in a protocol failure,
+		 * if a TX operation is in transit. The caller
+		 * could unconditional wait to give the current
+		 * operation a chance to complete.
+		 * Esp., how to handle the non-empty IRQ case?
+		 * The peer was asking for data transfer at a valid
+		 * point in time.
+		 */
+		siw_sq_flush(qp);
+		siw_rq_flush(qp);
+		qp->attrs.state = SIW_QP_STATE_ERROR;
+		drop_conn = 1;
+		break;
+
+	default:
+		break;
+	}
+	return drop_conn;
+}
+
+static void siw_qp_nextstate_from_term(struct siw_qp *qp,
+				       struct siw_qp_attrs *attrs)
+{
+	switch (attrs->state) {
+	case SIW_QP_STATE_ERROR:
+		siw_rq_flush(qp);
+		qp->attrs.state = SIW_QP_STATE_ERROR;
+
+		if (tx_wqe(qp)->wr_status != SIW_WR_IDLE)
+			siw_sq_flush(qp);
+		break;
+
+	default:
+		break;
+	}
+}
+
+static int siw_qp_nextstate_from_close(struct siw_qp *qp,
+				       struct siw_qp_attrs *attrs)
+{
+	int rv = 0;
+
+	switch (attrs->state) {
+	case SIW_QP_STATE_IDLE:
+		WARN_ON(tx_wqe(qp)->wr_status != SIW_WR_IDLE);
+		qp->attrs.state = SIW_QP_STATE_IDLE;
+		break;
+
+	case SIW_QP_STATE_CLOSING:
+		/*
+		 * The LLP may already moved the QP to closing
+		 * due to graceful peer close init
+		 */
+		break;
+
+	case SIW_QP_STATE_ERROR:
+		/*
+		 * QP was moved to CLOSING by LLP event
+		 * not yet seen by user.
+		 */
+		qp->attrs.state = SIW_QP_STATE_ERROR;
+
+		if (tx_wqe(qp)->wr_status != SIW_WR_IDLE)
+			siw_sq_flush(qp);
+
+		siw_rq_flush(qp);
+		break;
+
+	default:
+		siw_dbg_qp(qp, "state transition undefined: %s => %s\n",
+			   siw_qp_state_to_string[qp->attrs.state],
+			   siw_qp_state_to_string[attrs->state]);
+
+		rv = -ECONNABORTED;
+	}
+	return rv;
+}
+
+/*
+ * Caller must hold qp->state_lock
+ */
+int siw_qp_modify(struct siw_qp *qp, struct siw_qp_attrs *attrs,
+		  enum siw_qp_attr_mask mask)
+{
+	int drop_conn = 0, rv = 0;
+
+	if (!mask)
+		return 0;
+
+	siw_dbg_qp(qp, "state: %s => %s\n",
+		   siw_qp_state_to_string[qp->attrs.state],
+		   siw_qp_state_to_string[attrs->state]);
+
+	if (mask != SIW_QP_ATTR_STATE)
+		siw_qp_modify_nonstate(qp, attrs, mask);
+
+	if (!(mask & SIW_QP_ATTR_STATE))
+		return 0;
+
+	switch (qp->attrs.state) {
+	case SIW_QP_STATE_IDLE:
+	case SIW_QP_STATE_RTR:
+		rv = siw_qp_nextstate_from_idle(qp, attrs, mask);
+		break;
+
+	case SIW_QP_STATE_RTS:
+		drop_conn = siw_qp_nextstate_from_rts(qp, attrs);
+		break;
+
+	case SIW_QP_STATE_TERMINATE:
+		siw_qp_nextstate_from_term(qp, attrs);
+		break;
+
+	case SIW_QP_STATE_CLOSING:
+		siw_qp_nextstate_from_close(qp, attrs);
+		break;
+	default:
+		break;
+	}
+	if (drop_conn)
+		siw_qp_cm_drop(qp, 0);
+
+	return rv;
+}
+
+void siw_read_to_orq(struct siw_sqe *rreq, struct siw_sqe *sqe)
+{
+	rreq->id = sqe->id;
+	rreq->opcode = sqe->opcode;
+	rreq->sge[0].laddr = sqe->sge[0].laddr;
+	rreq->sge[0].length = sqe->sge[0].length;
+	rreq->sge[0].lkey = sqe->sge[0].lkey;
+	rreq->sge[1].lkey = sqe->sge[1].lkey;
+	rreq->flags = sqe->flags | SIW_WQE_VALID;
+	rreq->num_sge = 1;
+}
+
+/*
+ * Must be called with SQ locked.
+ * To avoid complete SQ starvation by constant inbound READ requests,
+ * the active IRQ will not be served after qp->irq_burst, if the
+ * SQ has pending work.
+ */
+int siw_activate_tx(struct siw_qp *qp)
+{
+	struct siw_sqe *irqe, *sqe;
+	struct siw_wqe *wqe = tx_wqe(qp);
+	int rv = 1;
+
+	irqe = &qp->irq[qp->irq_get % qp->attrs.irq_size];
+
+	if (irqe->flags & SIW_WQE_VALID) {
+		sqe = sq_get_next(qp);
+
+		/*
+		 * Avoid local WQE processing starvation in case
+		 * of constant inbound READ request stream
+		 */
+		if (sqe && ++qp->irq_burst >= SIW_IRQ_MAXBURST_SQ_ACTIVE) {
+			qp->irq_burst = 0;
+			goto skip_irq;
+		}
+		memset(wqe->mem, 0, sizeof(*wqe->mem) * SIW_MAX_SGE);
+		wqe->wr_status = SIW_WR_QUEUED;
+
+		/* start READ RESPONSE */
+		wqe->sqe.opcode = SIW_OP_READ_RESPONSE;
+		wqe->sqe.flags = 0;
+		if (irqe->num_sge) {
+			wqe->sqe.num_sge = 1;
+			wqe->sqe.sge[0].length = irqe->sge[0].length;
+			wqe->sqe.sge[0].laddr = irqe->sge[0].laddr;
+			wqe->sqe.sge[0].lkey = irqe->sge[0].lkey;
+		} else {
+			wqe->sqe.num_sge = 0;
+		}
+
+		/* Retain original RREQ's message sequence number for
+		 * potential error reporting cases.
+		 */
+		wqe->sqe.sge[1].length = irqe->sge[1].length;
+
+		wqe->sqe.rkey = irqe->rkey;
+		wqe->sqe.raddr = irqe->raddr;
+
+		wqe->processed = 0;
+		qp->irq_get++;
+
+		/* mark current IRQ entry free */
+		smp_store_mb(irqe->flags, 0);
+
+		goto out;
+	}
+	sqe = sq_get_next(qp);
+	if (sqe) {
+skip_irq:
+		memset(wqe->mem, 0, sizeof(*wqe->mem) * SIW_MAX_SGE);
+		wqe->wr_status = SIW_WR_QUEUED;
+
+		/* First copy SQE to kernel private memory */
+		memcpy(&wqe->sqe, sqe, sizeof(*sqe));
+
+		if (wqe->sqe.opcode >= SIW_NUM_OPCODES) {
+			rv = -EINVAL;
+			goto out;
+		}
+		if (wqe->sqe.flags & SIW_WQE_INLINE) {
+			if (wqe->sqe.opcode != SIW_OP_SEND &&
+			    wqe->sqe.opcode != SIW_OP_WRITE) {
+				rv = -EINVAL;
+				goto out;
+			}
+			if (wqe->sqe.sge[0].length > SIW_MAX_INLINE) {
+				rv = -EINVAL;
+				goto out;
+			}
+			wqe->sqe.sge[0].laddr = (u64)&wqe->sqe.sge[1];
+			wqe->sqe.sge[0].lkey = 0;
+			wqe->sqe.num_sge = 1;
+		}
+		if (wqe->sqe.flags & SIW_WQE_READ_FENCE) {
+			/* A READ cannot be fenced */
+			if (unlikely(wqe->sqe.opcode == SIW_OP_READ ||
+				     wqe->sqe.opcode ==
+					     SIW_OP_READ_LOCAL_INV)) {
+				siw_dbg_qp(qp, "cannot fence read\n");
+				rv = -EINVAL;
+				goto out;
+			}
+			spin_lock(&qp->orq_lock);
+
+			if (!siw_orq_empty(qp)) {
+				qp->tx_ctx.orq_fence = 1;
+				rv = 0;
+			}
+			spin_unlock(&qp->orq_lock);
+
+		} else if (wqe->sqe.opcode == SIW_OP_READ ||
+			   wqe->sqe.opcode == SIW_OP_READ_LOCAL_INV) {
+			struct siw_sqe *rreq;
+
+			wqe->sqe.num_sge = 1;
+
+			spin_lock(&qp->orq_lock);
+
+			rreq = orq_get_free(qp);
+			if (rreq) {
+				/*
+				 * Make an immediate copy in ORQ to be ready
+				 * to process loopback READ reply
+				 */
+				siw_read_to_orq(rreq, &wqe->sqe);
+				qp->orq_put++;
+			} else {
+				qp->tx_ctx.orq_fence = 1;
+				rv = 0;
+			}
+			spin_unlock(&qp->orq_lock);
+		}
+
+		/* Clear SQE, can be re-used by application */
+		smp_store_mb(sqe->flags, 0);
+		qp->sq_get++;
+	} else {
+		rv = 0;
+	}
+out:
+	if (unlikely(rv < 0)) {
+		siw_dbg_qp(qp, "error %d\n", rv);
+		wqe->wr_status = SIW_WR_IDLE;
+	}
+	return rv;
+}
+
+/*
+ * Check if current CQ state qualifies for calling CQ completion
+ * handler. Must be called with CQ lock held.
+ */
+static bool siw_cq_notify_now(struct siw_cq *cq, u32 flags)
+{
+	u64 cq_notify;
+
+	if (!cq->base_cq.comp_handler)
+		return false;
+
+	cq_notify = READ_ONCE(*cq->notify);
+
+	if ((cq_notify & SIW_NOTIFY_NEXT_COMPLETION) ||
+	    ((cq_notify & SIW_NOTIFY_SOLICITED) &&
+	     (flags & SIW_WQE_SOLICITED))) {
+		/* dis-arm CQ */
+		smp_store_mb(*cq->notify, SIW_NOTIFY_NOT);
+
+		return true;
+	}
+	return false;
+}
+
+int siw_sqe_complete(struct siw_qp *qp, struct siw_sqe *sqe, u32 bytes,
+		     enum siw_wc_status status)
+{
+	struct siw_cq *cq = qp->scq;
+	int rv = 0;
+
+	if (cq) {
+		u32 sqe_flags = sqe->flags;
+		struct siw_cqe *cqe;
+		u32 idx;
+		unsigned long flags;
+
+		spin_lock_irqsave(&cq->lock, flags);
+
+		idx = cq->cq_put % cq->num_cqe;
+		cqe = &cq->queue[idx];
+
+		if (!READ_ONCE(cqe->flags)) {
+			bool notify;
+
+			cqe->id = sqe->id;
+			cqe->opcode = sqe->opcode;
+			cqe->status = status;
+			cqe->imm_data = 0;
+			cqe->bytes = bytes;
+
+			if (cq->kernel_verbs)
+				cqe->base_qp = qp->ib_qp;
+			else
+				cqe->qp_id = qp_id(qp);
+
+			/* mark CQE valid for application */
+			WRITE_ONCE(cqe->flags, SIW_WQE_VALID);
+			/* recycle SQE */
+			smp_store_mb(sqe->flags, 0);
+
+			cq->cq_put++;
+			notify = siw_cq_notify_now(cq, sqe_flags);
+
+			spin_unlock_irqrestore(&cq->lock, flags);
+
+			if (notify) {
+				siw_dbg_cq(cq, "Call completion handler\n");
+				cq->base_cq.comp_handler(&cq->base_cq,
+						cq->base_cq.cq_context);
+			}
+		} else {
+			spin_unlock_irqrestore(&cq->lock, flags);
+			rv = -ENOMEM;
+			siw_cq_event(cq, IB_EVENT_CQ_ERR);
+		}
+	} else {
+		/* recycle SQE */
+		smp_store_mb(sqe->flags, 0);
+	}
+	return rv;
+}
+
+int siw_rqe_complete(struct siw_qp *qp, struct siw_rqe *rqe, u32 bytes,
+		     u32 inval_stag, enum siw_wc_status status)
+{
+	struct siw_cq *cq = qp->rcq;
+	int rv = 0;
+
+	if (cq) {
+		struct siw_cqe *cqe;
+		u32 idx;
+		unsigned long flags;
+
+		spin_lock_irqsave(&cq->lock, flags);
+
+		idx = cq->cq_put % cq->num_cqe;
+		cqe = &cq->queue[idx];
+
+		if (!READ_ONCE(cqe->flags)) {
+			bool notify;
+			u8 cqe_flags = SIW_WQE_VALID;
+
+			cqe->id = rqe->id;
+			cqe->opcode = SIW_OP_RECEIVE;
+			cqe->status = status;
+			cqe->imm_data = 0;
+			cqe->bytes = bytes;
+
+			if (cq->kernel_verbs) {
+				cqe->base_qp = qp->ib_qp;
+				if (inval_stag) {
+					cqe_flags |= SIW_WQE_REM_INVAL;
+					cqe->inval_stag = inval_stag;
+				}
+			} else {
+				cqe->qp_id = qp_id(qp);
+			}
+			/* mark CQE valid for application */
+			WRITE_ONCE(cqe->flags, cqe_flags);
+			/* recycle RQE */
+			smp_store_mb(rqe->flags, 0);
+
+			cq->cq_put++;
+			notify = siw_cq_notify_now(cq, SIW_WQE_SIGNALLED);
+
+			spin_unlock_irqrestore(&cq->lock, flags);
+
+			if (notify) {
+				siw_dbg_cq(cq, "Call completion handler\n");
+				cq->base_cq.comp_handler(&cq->base_cq,
+						cq->base_cq.cq_context);
+			}
+		} else {
+			spin_unlock_irqrestore(&cq->lock, flags);
+			rv = -ENOMEM;
+			siw_cq_event(cq, IB_EVENT_CQ_ERR);
+		}
+	} else {
+		/* recycle RQE */
+		smp_store_mb(rqe->flags, 0);
+	}
+	return rv;
+}
+
+/*
+ * siw_sq_flush()
+ *
+ * Flush SQ and ORRQ entries to CQ.
+ *
+ * Must be called with QP state write lock held.
+ * Therefore, SQ and ORQ lock must not be taken.
+ */
+void siw_sq_flush(struct siw_qp *qp)
+{
+	struct siw_sqe *sqe;
+	struct siw_wqe *wqe = tx_wqe(qp);
+	int async_event = 0;
+
+	/*
+	 * Start with completing any work currently on the ORQ
+	 */
+	while (qp->attrs.orq_size) {
+		sqe = &qp->orq[qp->orq_get % qp->attrs.orq_size];
+		if (!READ_ONCE(sqe->flags))
+			break;
+
+		if (siw_sqe_complete(qp, sqe, 0, SIW_WC_WR_FLUSH_ERR) != 0)
+			break;
+
+		WRITE_ONCE(sqe->flags, 0);
+		qp->orq_get++;
+	}
+	/*
+	 * Flush an in-progress WQE if present
+	 */
+	if (wqe->wr_status != SIW_WR_IDLE) {
+		siw_dbg_qp(qp, "flush current SQE, type %d, status %d\n",
+			   tx_type(wqe), wqe->wr_status);
+
+		siw_wqe_put_mem(wqe, tx_type(wqe));
+
+		if (tx_type(wqe) != SIW_OP_READ_RESPONSE &&
+		    ((tx_type(wqe) != SIW_OP_READ &&
+		      tx_type(wqe) != SIW_OP_READ_LOCAL_INV) ||
+		     wqe->wr_status == SIW_WR_QUEUED))
+			/*
+			 * An in-progress Read Request is already in
+			 * the ORQ
+			 */
+			siw_sqe_complete(qp, &wqe->sqe, wqe->bytes,
+					 SIW_WC_WR_FLUSH_ERR);
+
+		wqe->wr_status = SIW_WR_IDLE;
+	}
+	/*
+	 * Flush the Send Queue
+	 */
+	while (qp->attrs.sq_size) {
+		sqe = &qp->sendq[qp->sq_get % qp->attrs.sq_size];
+		if (!READ_ONCE(sqe->flags))
+			break;
+
+		async_event = 1;
+		if (siw_sqe_complete(qp, sqe, 0, SIW_WC_WR_FLUSH_ERR) != 0)
+			/*
+			 * Shall IB_EVENT_SQ_DRAINED be supressed if work
+			 * completion fails?
+			 */
+			break;
+
+		WRITE_ONCE(sqe->flags, 0);
+		qp->sq_get++;
+	}
+	if (async_event)
+		siw_qp_event(qp, IB_EVENT_SQ_DRAINED);
+}
+
+/*
+ * siw_rq_flush()
+ *
+ * Flush recv queue entries to CQ. Also
+ * takes care of pending active tagged and untagged
+ * inbound transfers, which have target memory
+ * referenced.
+ *
+ * Must be called with QP state write lock held.
+ * Therefore, RQ lock must not be taken.
+ */
+void siw_rq_flush(struct siw_qp *qp)
+{
+	struct siw_wqe *wqe = &qp->rx_untagged.wqe_active;
+
+	/*
+	 * Flush an in-progress untagged operation if present
+	 */
+	if (wqe->wr_status != SIW_WR_IDLE) {
+		siw_dbg_qp(qp, "flush current rqe, type %d, status %d\n",
+			   rx_type(wqe), wqe->wr_status);
+
+		siw_wqe_put_mem(wqe, rx_type(wqe));
+
+		if (rx_type(wqe) == SIW_OP_RECEIVE) {
+			siw_rqe_complete(qp, &wqe->rqe, wqe->bytes,
+					 0, SIW_WC_WR_FLUSH_ERR);
+		} else if (rx_type(wqe) != SIW_OP_READ &&
+			   rx_type(wqe) != SIW_OP_READ_RESPONSE &&
+			   rx_type(wqe) != SIW_OP_WRITE) {
+			siw_sqe_complete(qp, &wqe->sqe, 0, SIW_WC_WR_FLUSH_ERR);
+		}
+		wqe->wr_status = SIW_WR_IDLE;
+	}
+	wqe = &qp->rx_tagged.wqe_active;
+
+	if (wqe->wr_status != SIW_WR_IDLE) {
+		siw_wqe_put_mem(wqe, rx_type(wqe));
+		wqe->wr_status = SIW_WR_IDLE;
+	}
+	/*
+	 * Flush the Receive Queue
+	 */
+	while (qp->attrs.rq_size) {
+		struct siw_rqe *rqe =
+			&qp->recvq[qp->rq_get % qp->attrs.rq_size];
+
+		if (!READ_ONCE(rqe->flags))
+			break;
+
+		if (siw_rqe_complete(qp, rqe, 0, 0, SIW_WC_WR_FLUSH_ERR) != 0)
+			break;
+
+		WRITE_ONCE(rqe->flags, 0);
+		qp->rq_get++;
+	}
+}
+
+int siw_qp_add(struct siw_device *sdev, struct siw_qp *qp)
+{
+	int rv = xa_alloc(&sdev->qp_xa, &qp->ib_qp->qp_num, qp, xa_limit_32b,
+			  GFP_KERNEL);
+
+	if (!rv) {
+		kref_init(&qp->ref);
+		qp->sdev = sdev;
+		qp->qp_num = qp->ib_qp->qp_num;
+		siw_dbg_qp(qp, "new QP\n");
+	}
+	return rv;
+}
+
+void siw_free_qp(struct kref *ref)
+{
+	struct siw_qp *found, *qp = container_of(ref, struct siw_qp, ref);
+	struct siw_device *sdev = qp->sdev;
+	unsigned long flags;
+
+	if (qp->cep)
+		siw_cep_put(qp->cep);
+
+	found = xa_erase(&sdev->qp_xa, qp_id(qp));
+	WARN_ON(found != qp);
+	spin_lock_irqsave(&sdev->lock, flags);
+	list_del(&qp->devq);
+	spin_unlock_irqrestore(&sdev->lock, flags);
+
+	vfree(qp->sendq);
+	vfree(qp->recvq);
+	vfree(qp->irq);
+	vfree(qp->orq);
+
+	siw_put_tx_cpu(qp->tx_cpu);
+
+	atomic_dec(&sdev->num_qp);
+	siw_dbg_qp(qp, "free QP\n");
+	kfree_rcu(qp, rcu);
+}
diff --git a/drivers/infiniband/sw/siw/siw_qp_rx.c b/drivers/infiniband/sw/siw/siw_qp_rx.c
new file mode 100644
index 000000000000..682a290bc11e
--- /dev/null
+++ b/drivers/infiniband/sw/siw/siw_qp_rx.c
@@ -0,0 +1,1456 @@
+// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/net.h>
+#include <linux/scatterlist.h>
+#include <linux/highmem.h>
+
+#include <rdma/iw_cm.h>
+#include <rdma/ib_verbs.h>
+
+#include "siw.h"
+#include "siw_verbs.h"
+#include "siw_mem.h"
+
+/*
+ * siw_rx_umem()
+ *
+ * Receive data of @len into target referenced by @dest_addr.
+ *
+ * @srx:	Receive Context
+ * @umem:	siw representation of target memory
+ * @dest_addr:	user virtual address
+ * @len:	number of bytes to place
+ */
+static int siw_rx_umem(struct siw_rx_stream *srx, struct siw_umem *umem,
+		       u64 dest_addr, int len)
+{
+	int copied = 0;
+
+	while (len) {
+		struct page *p;
+		int pg_off, bytes, rv;
+		void *dest;
+
+		p = siw_get_upage(umem, dest_addr);
+		if (unlikely(!p)) {
+			pr_warn("siw: %s: [QP %u]: bogus addr: %p, %p\n",
+				__func__, qp_id(rx_qp(srx)),
+				(void *)dest_addr, (void *)umem->fp_addr);
+			/* siw internal error */
+			srx->skb_copied += copied;
+			srx->skb_new -= copied;
+
+			return -EFAULT;
+		}
+		pg_off = dest_addr & ~PAGE_MASK;
+		bytes = min(len, (int)PAGE_SIZE - pg_off);
+
+		siw_dbg_qp(rx_qp(srx), "page %p, bytes=%u\n", p, bytes);
+
+		dest = kmap_atomic(p);
+		rv = skb_copy_bits(srx->skb, srx->skb_offset, dest + pg_off,
+				   bytes);
+
+		if (unlikely(rv)) {
+			kunmap_atomic(dest);
+			srx->skb_copied += copied;
+			srx->skb_new -= copied;
+
+			pr_warn("siw: [QP %u]: %s, len %d, page %p, rv %d\n",
+				qp_id(rx_qp(srx)), __func__, len, p, rv);
+
+			return -EFAULT;
+		}
+		if (srx->mpa_crc_hd) {
+			if (rx_qp(srx)->kernel_verbs) {
+				crypto_shash_update(srx->mpa_crc_hd,
+					(u8 *)(dest + pg_off), bytes);
+				kunmap_atomic(dest);
+			} else {
+				kunmap_atomic(dest);
+				/*
+				 * Do CRC on original, not target buffer.
+				 * Some user land applications may
+				 * concurrently write the target buffer,
+				 * which would yield a broken CRC.
+				 * Walking the skb twice is very ineffcient.
+				 * Folding the CRC into skb_copy_bits()
+				 * would be much better, but is currently
+				 * not supported.
+				 */
+				siw_crc_skb(srx, bytes);
+			}
+		} else {
+			kunmap_atomic(dest);
+		}
+		srx->skb_offset += bytes;
+		copied += bytes;
+		len -= bytes;
+		dest_addr += bytes;
+		pg_off = 0;
+	}
+	srx->skb_copied += copied;
+	srx->skb_new -= copied;
+
+	return copied;
+}
+
+static int siw_rx_kva(struct siw_rx_stream *srx, void *kva, int len)
+{
+	int rv;
+
+	siw_dbg_qp(rx_qp(srx), "kva: 0x%p, len: %u\n", kva, len);
+
+	rv = skb_copy_bits(srx->skb, srx->skb_offset, kva, len);
+	if (unlikely(rv)) {
+		pr_warn("siw: [QP %u]: %s, len %d, kva 0x%p, rv %d\n",
+			qp_id(rx_qp(srx)), __func__, len, kva, rv);
+
+		return rv;
+	}
+	if (srx->mpa_crc_hd)
+		crypto_shash_update(srx->mpa_crc_hd, (u8 *)kva, len);
+
+	srx->skb_offset += len;
+	srx->skb_copied += len;
+	srx->skb_new -= len;
+
+	return len;
+}
+
+static int siw_rx_pbl(struct siw_rx_stream *srx, int *pbl_idx,
+		      struct siw_mem *mem, u64 addr, int len)
+{
+	struct siw_pbl *pbl = mem->pbl;
+	u64 offset = addr - mem->va;
+	int copied = 0;
+
+	while (len) {
+		int bytes;
+		u64 buf_addr =
+			siw_pbl_get_buffer(pbl, offset, &bytes, pbl_idx);
+		if (!buf_addr)
+			break;
+
+		bytes = min(bytes, len);
+		if (siw_rx_kva(srx, (void *)buf_addr, bytes) == bytes) {
+			copied += bytes;
+			offset += bytes;
+			len -= bytes;
+		} else {
+			break;
+		}
+	}
+	return copied;
+}
+
+/*
+ * siw_rresp_check_ntoh()
+ *
+ * Check incoming RRESP fragment header against expected
+ * header values and update expected values for potential next
+ * fragment.
+ *
+ * NOTE: This function must be called only if a RRESP DDP segment
+ *       starts but not for fragmented consecutive pieces of an
+ *       already started DDP segment.
+ */
+static int siw_rresp_check_ntoh(struct siw_rx_stream *srx,
+				struct siw_rx_fpdu *frx)
+{
+	struct iwarp_rdma_rresp *rresp = &srx->hdr.rresp;
+	struct siw_wqe *wqe = &frx->wqe_active;
+	enum ddp_ecode ecode;
+
+	u32 sink_stag = be32_to_cpu(rresp->sink_stag);
+	u64 sink_to = be64_to_cpu(rresp->sink_to);
+
+	if (frx->first_ddp_seg) {
+		srx->ddp_stag = wqe->sqe.sge[0].lkey;
+		srx->ddp_to = wqe->sqe.sge[0].laddr;
+		frx->pbl_idx = 0;
+	}
+	/* Below checks extend beyond the semantics of DDP, and
+	 * into RDMAP:
+	 * We check if the read response matches exactly the
+	 * read request which was send to the remote peer to
+	 * trigger this read response. RFC5040/5041 do not
+	 * always have a proper error code for the detected
+	 * error cases. We choose 'base or bounds error' for
+	 * cases where the inbound STag is valid, but offset
+	 * or length do not match our response receive state.
+	 */
+	if (unlikely(srx->ddp_stag != sink_stag)) {
+		pr_warn("siw: [QP %u]: rresp stag: %08x != %08x\n",
+			qp_id(rx_qp(srx)), sink_stag, srx->ddp_stag);
+		ecode = DDP_ECODE_T_INVALID_STAG;
+		goto error;
+	}
+	if (unlikely(srx->ddp_to != sink_to)) {
+		pr_warn("siw: [QP %u]: rresp off: %016llx != %016llx\n",
+			qp_id(rx_qp(srx)), (unsigned long long)sink_to,
+			(unsigned long long)srx->ddp_to);
+		ecode = DDP_ECODE_T_BASE_BOUNDS;
+		goto error;
+	}
+	if (unlikely(!frx->more_ddp_segs &&
+		     (wqe->processed + srx->fpdu_part_rem != wqe->bytes))) {
+		pr_warn("siw: [QP %u]: rresp len: %d != %d\n",
+			qp_id(rx_qp(srx)),
+			wqe->processed + srx->fpdu_part_rem, wqe->bytes);
+		ecode = DDP_ECODE_T_BASE_BOUNDS;
+		goto error;
+	}
+	return 0;
+error:
+	siw_init_terminate(rx_qp(srx), TERM_ERROR_LAYER_DDP,
+			   DDP_ETYPE_TAGGED_BUF, ecode, 0);
+	return -EINVAL;
+}
+
+/*
+ * siw_write_check_ntoh()
+ *
+ * Check incoming WRITE fragment header against expected
+ * header values and update expected values for potential next
+ * fragment
+ *
+ * NOTE: This function must be called only if a WRITE DDP segment
+ *       starts but not for fragmented consecutive pieces of an
+ *       already started DDP segment.
+ */
+static int siw_write_check_ntoh(struct siw_rx_stream *srx,
+				struct siw_rx_fpdu *frx)
+{
+	struct iwarp_rdma_write *write = &srx->hdr.rwrite;
+	enum ddp_ecode ecode;
+
+	u32 sink_stag = be32_to_cpu(write->sink_stag);
+	u64 sink_to = be64_to_cpu(write->sink_to);
+
+	if (frx->first_ddp_seg) {
+		srx->ddp_stag = sink_stag;
+		srx->ddp_to = sink_to;
+		frx->pbl_idx = 0;
+	} else {
+		if (unlikely(srx->ddp_stag != sink_stag)) {
+			pr_warn("siw: [QP %u]: write stag: %08x != %08x\n",
+				qp_id(rx_qp(srx)), sink_stag,
+				srx->ddp_stag);
+			ecode = DDP_ECODE_T_INVALID_STAG;
+			goto error;
+		}
+		if (unlikely(srx->ddp_to != sink_to)) {
+			pr_warn("siw: [QP %u]: write off: %016llx != %016llx\n",
+				qp_id(rx_qp(srx)),
+				(unsigned long long)sink_to,
+				(unsigned long long)srx->ddp_to);
+			ecode = DDP_ECODE_T_BASE_BOUNDS;
+			goto error;
+		}
+	}
+	return 0;
+error:
+	siw_init_terminate(rx_qp(srx), TERM_ERROR_LAYER_DDP,
+			   DDP_ETYPE_TAGGED_BUF, ecode, 0);
+	return -EINVAL;
+}
+
+/*
+ * siw_send_check_ntoh()
+ *
+ * Check incoming SEND fragment header against expected
+ * header values and update expected MSN if no next
+ * fragment expected
+ *
+ * NOTE: This function must be called only if a SEND DDP segment
+ *       starts but not for fragmented consecutive pieces of an
+ *       already started DDP segment.
+ */
+static int siw_send_check_ntoh(struct siw_rx_stream *srx,
+			       struct siw_rx_fpdu *frx)
+{
+	struct iwarp_send_inv *send = &srx->hdr.send_inv;
+	struct siw_wqe *wqe = &frx->wqe_active;
+	enum ddp_ecode ecode;
+
+	u32 ddp_msn = be32_to_cpu(send->ddp_msn);
+	u32 ddp_mo = be32_to_cpu(send->ddp_mo);
+	u32 ddp_qn = be32_to_cpu(send->ddp_qn);
+
+	if (unlikely(ddp_qn != RDMAP_UNTAGGED_QN_SEND)) {
+		pr_warn("siw: [QP %u]: invalid ddp qn %d for send\n",
+			qp_id(rx_qp(srx)), ddp_qn);
+		ecode = DDP_ECODE_UT_INVALID_QN;
+		goto error;
+	}
+	if (unlikely(ddp_msn != srx->ddp_msn[RDMAP_UNTAGGED_QN_SEND])) {
+		pr_warn("siw: [QP %u]: send msn: %u != %u\n",
+			qp_id(rx_qp(srx)), ddp_msn,
+			srx->ddp_msn[RDMAP_UNTAGGED_QN_SEND]);
+		ecode = DDP_ECODE_UT_INVALID_MSN_RANGE;
+		goto error;
+	}
+	if (unlikely(ddp_mo != wqe->processed)) {
+		pr_warn("siw: [QP %u], send mo: %u != %u\n",
+			qp_id(rx_qp(srx)), ddp_mo, wqe->processed);
+		ecode = DDP_ECODE_UT_INVALID_MO;
+		goto error;
+	}
+	if (frx->first_ddp_seg) {
+		/* initialize user memory write position */
+		frx->sge_idx = 0;
+		frx->sge_off = 0;
+		frx->pbl_idx = 0;
+
+		/* only valid for SEND_INV and SEND_SE_INV operations */
+		srx->inval_stag = be32_to_cpu(send->inval_stag);
+	}
+	if (unlikely(wqe->bytes < wqe->processed + srx->fpdu_part_rem)) {
+		siw_dbg_qp(rx_qp(srx), "receive space short: %d - %d < %d\n",
+			   wqe->bytes, wqe->processed, srx->fpdu_part_rem);
+		wqe->wc_status = SIW_WC_LOC_LEN_ERR;
+		ecode = DDP_ECODE_UT_INVALID_MSN_NOBUF;
+		goto error;
+	}
+	return 0;
+error:
+	siw_init_terminate(rx_qp(srx), TERM_ERROR_LAYER_DDP,
+			   DDP_ETYPE_UNTAGGED_BUF, ecode, 0);
+	return -EINVAL;
+}
+
+static struct siw_wqe *siw_rqe_get(struct siw_qp *qp)
+{
+	struct siw_rqe *rqe;
+	struct siw_srq *srq;
+	struct siw_wqe *wqe = NULL;
+	bool srq_event = false;
+	unsigned long flags;
+
+	srq = qp->srq;
+	if (srq) {
+		spin_lock_irqsave(&srq->lock, flags);
+		if (unlikely(!srq->num_rqe))
+			goto out;
+
+		rqe = &srq->recvq[srq->rq_get % srq->num_rqe];
+	} else {
+		if (unlikely(!qp->recvq))
+			goto out;
+
+		rqe = &qp->recvq[qp->rq_get % qp->attrs.rq_size];
+	}
+	if (likely(rqe->flags == SIW_WQE_VALID)) {
+		int num_sge = rqe->num_sge;
+
+		if (likely(num_sge <= SIW_MAX_SGE)) {
+			int i = 0;
+
+			wqe = rx_wqe(&qp->rx_untagged);
+			rx_type(wqe) = SIW_OP_RECEIVE;
+			wqe->wr_status = SIW_WR_INPROGRESS;
+			wqe->bytes = 0;
+			wqe->processed = 0;
+
+			wqe->rqe.id = rqe->id;
+			wqe->rqe.num_sge = num_sge;
+
+			while (i < num_sge) {
+				wqe->rqe.sge[i].laddr = rqe->sge[i].laddr;
+				wqe->rqe.sge[i].lkey = rqe->sge[i].lkey;
+				wqe->rqe.sge[i].length = rqe->sge[i].length;
+				wqe->bytes += wqe->rqe.sge[i].length;
+				wqe->mem[i] = NULL;
+				i++;
+			}
+			/* can be re-used by appl */
+			smp_store_mb(rqe->flags, 0);
+		} else {
+			siw_dbg_qp(qp, "too many sge's: %d\n", rqe->num_sge);
+			if (srq)
+				spin_unlock_irqrestore(&srq->lock, flags);
+			return NULL;
+		}
+		if (!srq) {
+			qp->rq_get++;
+		} else {
+			if (srq->armed) {
+				/* Test SRQ limit */
+				u32 off = (srq->rq_get + srq->limit) %
+					  srq->num_rqe;
+				struct siw_rqe *rqe2 = &srq->recvq[off];
+
+				if (!(rqe2->flags & SIW_WQE_VALID)) {
+					srq->armed = 0;
+					srq_event = true;
+				}
+			}
+			srq->rq_get++;
+		}
+	}
+out:
+	if (srq) {
+		spin_unlock_irqrestore(&srq->lock, flags);
+		if (srq_event)
+			siw_srq_event(srq, IB_EVENT_SRQ_LIMIT_REACHED);
+	}
+	return wqe;
+}
+
+/*
+ * siw_proc_send:
+ *
+ * Process one incoming SEND and place data into memory referenced by
+ * receive wqe.
+ *
+ * Function supports partially received sends (suspending/resuming
+ * current receive wqe processing)
+ *
+ * return value:
+ *	0:       reached the end of a DDP segment
+ *	-EAGAIN: to be called again to finish the DDP segment
+ */
+int siw_proc_send(struct siw_qp *qp)
+{
+	struct siw_rx_stream *srx = &qp->rx_stream;
+	struct siw_rx_fpdu *frx = &qp->rx_untagged;
+	struct siw_wqe *wqe;
+	u32 data_bytes; /* all data bytes available */
+	u32 rcvd_bytes; /* sum of data bytes rcvd */
+	int rv = 0;
+
+	if (frx->first_ddp_seg) {
+		wqe = siw_rqe_get(qp);
+		if (unlikely(!wqe)) {
+			siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
+					   DDP_ETYPE_UNTAGGED_BUF,
+					   DDP_ECODE_UT_INVALID_MSN_NOBUF, 0);
+			return -ENOENT;
+		}
+	} else {
+		wqe = rx_wqe(frx);
+	}
+	if (srx->state == SIW_GET_DATA_START) {
+		rv = siw_send_check_ntoh(srx, frx);
+		if (unlikely(rv)) {
+			siw_qp_event(qp, IB_EVENT_QP_FATAL);
+			return rv;
+		}
+		if (!srx->fpdu_part_rem) /* zero length SEND */
+			return 0;
+	}
+	data_bytes = min(srx->fpdu_part_rem, srx->skb_new);
+	rcvd_bytes = 0;
+
+	/* A zero length SEND will skip below loop */
+	while (data_bytes) {
+		struct ib_pd *pd;
+		struct siw_mem **mem, *mem_p;
+		struct siw_sge *sge;
+		u32 sge_bytes; /* data bytes avail for SGE */
+
+		sge = &wqe->rqe.sge[frx->sge_idx];
+
+		if (!sge->length) {
+			/* just skip empty sge's */
+			frx->sge_idx++;
+			frx->sge_off = 0;
+			frx->pbl_idx = 0;
+			continue;
+		}
+		sge_bytes = min(data_bytes, sge->length - frx->sge_off);
+		mem = &wqe->mem[frx->sge_idx];
+
+		/*
+		 * check with QP's PD if no SRQ present, SRQ's PD otherwise
+		 */
+		pd = qp->srq == NULL ? qp->pd : qp->srq->base_srq.pd;
+
+		rv = siw_check_sge(pd, sge, mem, IB_ACCESS_LOCAL_WRITE,
+				   frx->sge_off, sge_bytes);
+		if (unlikely(rv)) {
+			siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
+					   DDP_ETYPE_CATASTROPHIC,
+					   DDP_ECODE_CATASTROPHIC, 0);
+
+			siw_qp_event(qp, IB_EVENT_QP_ACCESS_ERR);
+			break;
+		}
+		mem_p = *mem;
+		if (mem_p->mem_obj == NULL)
+			rv = siw_rx_kva(srx,
+					(void *)(sge->laddr + frx->sge_off),
+					sge_bytes);
+		else if (!mem_p->is_pbl)
+			rv = siw_rx_umem(srx, mem_p->umem,
+					 sge->laddr + frx->sge_off, sge_bytes);
+		else
+			rv = siw_rx_pbl(srx, &frx->pbl_idx, mem_p,
+					sge->laddr + frx->sge_off, sge_bytes);
+
+		if (unlikely(rv != sge_bytes)) {
+			wqe->processed += rcvd_bytes;
+
+			siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
+					   DDP_ETYPE_CATASTROPHIC,
+					   DDP_ECODE_CATASTROPHIC, 0);
+			return -EINVAL;
+		}
+		frx->sge_off += rv;
+
+		if (frx->sge_off == sge->length) {
+			frx->sge_idx++;
+			frx->sge_off = 0;
+			frx->pbl_idx = 0;
+		}
+		data_bytes -= rv;
+		rcvd_bytes += rv;
+
+		srx->fpdu_part_rem -= rv;
+		srx->fpdu_part_rcvd += rv;
+	}
+	wqe->processed += rcvd_bytes;
+
+	if (!srx->fpdu_part_rem)
+		return 0;
+
+	return (rv < 0) ? rv : -EAGAIN;
+}
+
+/*
+ * siw_proc_write:
+ *
+ * Place incoming WRITE after referencing and checking target buffer
+
+ * Function supports partially received WRITEs (suspending/resuming
+ * current receive processing)
+ *
+ * return value:
+ *	0:       reached the end of a DDP segment
+ *	-EAGAIN: to be called again to finish the DDP segment
+ */
+int siw_proc_write(struct siw_qp *qp)
+{
+	struct siw_rx_stream *srx = &qp->rx_stream;
+	struct siw_rx_fpdu *frx = &qp->rx_tagged;
+	struct siw_mem *mem;
+	int bytes, rv;
+
+	if (srx->state == SIW_GET_DATA_START) {
+		if (!srx->fpdu_part_rem) /* zero length WRITE */
+			return 0;
+
+		rv = siw_write_check_ntoh(srx, frx);
+		if (unlikely(rv)) {
+			siw_qp_event(qp, IB_EVENT_QP_FATAL);
+			return rv;
+		}
+	}
+	bytes = min(srx->fpdu_part_rem, srx->skb_new);
+
+	if (frx->first_ddp_seg) {
+		struct siw_wqe *wqe = rx_wqe(frx);
+
+		rx_mem(frx) = siw_mem_id2obj(qp->sdev, srx->ddp_stag >> 8);
+		if (unlikely(!rx_mem(frx))) {
+			siw_dbg_qp(qp,
+				   "sink stag not found/invalid, stag 0x%08x\n",
+				   srx->ddp_stag);
+
+			siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
+					   DDP_ETYPE_TAGGED_BUF,
+					   DDP_ECODE_T_INVALID_STAG, 0);
+			return -EINVAL;
+		}
+		wqe->rqe.num_sge = 1;
+		rx_type(wqe) = SIW_OP_WRITE;
+		wqe->wr_status = SIW_WR_INPROGRESS;
+	}
+	mem = rx_mem(frx);
+
+	/*
+	 * Check if application re-registered memory with different
+	 * key field of STag.
+	 */
+	if (unlikely(mem->stag != srx->ddp_stag)) {
+		siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
+				   DDP_ETYPE_TAGGED_BUF,
+				   DDP_ECODE_T_INVALID_STAG, 0);
+		return -EINVAL;
+	}
+	rv = siw_check_mem(qp->pd, mem, srx->ddp_to + srx->fpdu_part_rcvd,
+			   IB_ACCESS_REMOTE_WRITE, bytes);
+	if (unlikely(rv)) {
+		siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
+				   DDP_ETYPE_TAGGED_BUF, siw_tagged_error(-rv),
+				   0);
+
+		siw_qp_event(qp, IB_EVENT_QP_ACCESS_ERR);
+
+		return -EINVAL;
+	}
+
+	if (mem->mem_obj == NULL)
+		rv = siw_rx_kva(srx,
+				(void *)(srx->ddp_to + srx->fpdu_part_rcvd),
+				bytes);
+	else if (!mem->is_pbl)
+		rv = siw_rx_umem(srx, mem->umem,
+				 srx->ddp_to + srx->fpdu_part_rcvd, bytes);
+	else
+		rv = siw_rx_pbl(srx, &frx->pbl_idx, mem,
+				srx->ddp_to + srx->fpdu_part_rcvd, bytes);
+
+	if (unlikely(rv != bytes)) {
+		siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
+				   DDP_ETYPE_CATASTROPHIC,
+				   DDP_ECODE_CATASTROPHIC, 0);
+		return -EINVAL;
+	}
+	srx->fpdu_part_rem -= rv;
+	srx->fpdu_part_rcvd += rv;
+
+	if (!srx->fpdu_part_rem) {
+		srx->ddp_to += srx->fpdu_part_rcvd;
+		return 0;
+	}
+	return -EAGAIN;
+}
+
+/*
+ * Inbound RREQ's cannot carry user data.
+ */
+int siw_proc_rreq(struct siw_qp *qp)
+{
+	struct siw_rx_stream *srx = &qp->rx_stream;
+
+	if (!srx->fpdu_part_rem)
+		return 0;
+
+	pr_warn("siw: [QP %u]: rreq with mpa len %d\n", qp_id(qp),
+		be16_to_cpu(srx->hdr.ctrl.mpa_len));
+
+	return -EPROTO;
+}
+
+/*
+ * siw_init_rresp:
+ *
+ * Process inbound RDMA READ REQ. Produce a pseudo READ RESPONSE WQE.
+ * Put it at the tail of the IRQ, if there is another WQE currently in
+ * transmit processing. If not, make it the current WQE to be processed
+ * and schedule transmit processing.
+ *
+ * Can be called from softirq context and from process
+ * context (RREAD socket loopback case!)
+ *
+ * return value:
+ *	0:      success,
+ *		failure code otherwise
+ */
+
+static int siw_init_rresp(struct siw_qp *qp, struct siw_rx_stream *srx)
+{
+	struct siw_wqe *tx_work = tx_wqe(qp);
+	struct siw_sqe *resp;
+
+	uint64_t raddr = be64_to_cpu(srx->hdr.rreq.sink_to),
+		 laddr = be64_to_cpu(srx->hdr.rreq.source_to);
+	uint32_t length = be32_to_cpu(srx->hdr.rreq.read_size),
+		 lkey = be32_to_cpu(srx->hdr.rreq.source_stag),
+		 rkey = be32_to_cpu(srx->hdr.rreq.sink_stag),
+		 msn = be32_to_cpu(srx->hdr.rreq.ddp_msn);
+
+	int run_sq = 1, rv = 0;
+	unsigned long flags;
+
+	if (unlikely(msn != srx->ddp_msn[RDMAP_UNTAGGED_QN_RDMA_READ])) {
+		siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
+				   DDP_ETYPE_UNTAGGED_BUF,
+				   DDP_ECODE_UT_INVALID_MSN_RANGE, 0);
+		return -EPROTO;
+	}
+	spin_lock_irqsave(&qp->sq_lock, flags);
+
+	if (tx_work->wr_status == SIW_WR_IDLE) {
+		/*
+		 * immediately schedule READ response w/o
+		 * consuming IRQ entry: IRQ must be empty.
+		 */
+		tx_work->processed = 0;
+		tx_work->mem[0] = NULL;
+		tx_work->wr_status = SIW_WR_QUEUED;
+		resp = &tx_work->sqe;
+	} else {
+		resp = irq_alloc_free(qp);
+		run_sq = 0;
+	}
+	if (likely(resp)) {
+		resp->opcode = SIW_OP_READ_RESPONSE;
+
+		resp->sge[0].length = length;
+		resp->sge[0].laddr = laddr;
+		resp->sge[0].lkey = lkey;
+
+		/* Keep aside message sequence number for potential
+		 * error reporting during Read Response generation.
+		 */
+		resp->sge[1].length = msn;
+
+		resp->raddr = raddr;
+		resp->rkey = rkey;
+		resp->num_sge = length ? 1 : 0;
+
+		/* RRESP now valid as current TX wqe or placed into IRQ */
+		smp_store_mb(resp->flags, SIW_WQE_VALID);
+	} else {
+		pr_warn("siw: [QP %u]: irq %d exceeded %d\n", qp_id(qp),
+			qp->irq_put % qp->attrs.irq_size, qp->attrs.irq_size);
+
+		siw_init_terminate(qp, TERM_ERROR_LAYER_RDMAP,
+				   RDMAP_ETYPE_REMOTE_OPERATION,
+				   RDMAP_ECODE_CATASTROPHIC_STREAM, 0);
+		rv = -EPROTO;
+	}
+
+	spin_unlock_irqrestore(&qp->sq_lock, flags);
+
+	if (run_sq)
+		rv = siw_sq_start(qp);
+
+	return rv;
+}
+
+/*
+ * Only called at start of Read.Resonse processing.
+ * Transfer pending Read from tip of ORQ into currrent rx wqe,
+ * but keep ORQ entry valid until Read.Response processing done.
+ * No Queue locking needed.
+ */
+static int siw_orqe_start_rx(struct siw_qp *qp)
+{
+	struct siw_sqe *orqe;
+	struct siw_wqe *wqe = NULL;
+
+	/* make sure ORQ indices are current */
+	smp_mb();
+
+	orqe = orq_get_current(qp);
+	if (READ_ONCE(orqe->flags) & SIW_WQE_VALID) {
+		/* RRESP is a TAGGED RDMAP operation */
+		wqe = rx_wqe(&qp->rx_tagged);
+		wqe->sqe.id = orqe->id;
+		wqe->sqe.opcode = orqe->opcode;
+		wqe->sqe.sge[0].laddr = orqe->sge[0].laddr;
+		wqe->sqe.sge[0].lkey = orqe->sge[0].lkey;
+		wqe->sqe.sge[0].length = orqe->sge[0].length;
+		wqe->sqe.flags = orqe->flags;
+		wqe->sqe.num_sge = 1;
+		wqe->bytes = orqe->sge[0].length;
+		wqe->processed = 0;
+		wqe->mem[0] = NULL;
+		/* make sure WQE is completely written before valid */
+		smp_wmb();
+		wqe->wr_status = SIW_WR_INPROGRESS;
+
+		return 0;
+	}
+	return -EPROTO;
+}
+
+/*
+ * siw_proc_rresp:
+ *
+ * Place incoming RRESP data into memory referenced by RREQ WQE
+ * which is at the tip of the ORQ
+ *
+ * Function supports partially received RRESP's (suspending/resuming
+ * current receive processing)
+ */
+int siw_proc_rresp(struct siw_qp *qp)
+{
+	struct siw_rx_stream *srx = &qp->rx_stream;
+	struct siw_rx_fpdu *frx = &qp->rx_tagged;
+	struct siw_wqe *wqe = rx_wqe(frx);
+	struct siw_mem **mem, *mem_p;
+	struct siw_sge *sge;
+	int bytes, rv;
+
+	if (frx->first_ddp_seg) {
+		if (unlikely(wqe->wr_status != SIW_WR_IDLE)) {
+			pr_warn("siw: [QP %u]: proc RRESP: status %d, op %d\n",
+				qp_id(qp), wqe->wr_status, wqe->sqe.opcode);
+			rv = -EPROTO;
+			goto error_term;
+		}
+		/*
+		 * fetch pending RREQ from orq
+		 */
+		rv = siw_orqe_start_rx(qp);
+		if (rv) {
+			pr_warn("siw: [QP %u]: ORQ empty at idx %d\n",
+				qp_id(qp), qp->orq_get % qp->attrs.orq_size);
+			goto error_term;
+		}
+		rv = siw_rresp_check_ntoh(srx, frx);
+		if (unlikely(rv)) {
+			siw_qp_event(qp, IB_EVENT_QP_FATAL);
+			return rv;
+		}
+	} else {
+		if (unlikely(wqe->wr_status != SIW_WR_INPROGRESS)) {
+			pr_warn("siw: [QP %u]: resume RRESP: status %d\n",
+				qp_id(qp), wqe->wr_status);
+			rv = -EPROTO;
+			goto error_term;
+		}
+	}
+	if (!srx->fpdu_part_rem) /* zero length RRESPONSE */
+		return 0;
+
+	sge = wqe->sqe.sge; /* there is only one */
+	mem = &wqe->mem[0];
+
+	if (!(*mem)) {
+		/*
+		 * check target memory which resolves memory on first fragment
+		 */
+		rv = siw_check_sge(qp->pd, sge, mem, IB_ACCESS_LOCAL_WRITE, 0,
+				   wqe->bytes);
+		if (unlikely(rv)) {
+			siw_dbg_qp(qp, "target mem check: %d\n", rv);
+			wqe->wc_status = SIW_WC_LOC_PROT_ERR;
+
+			siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
+					   DDP_ETYPE_TAGGED_BUF,
+					   siw_tagged_error(-rv), 0);
+
+			siw_qp_event(qp, IB_EVENT_QP_ACCESS_ERR);
+
+			return -EINVAL;
+		}
+	}
+	mem_p = *mem;
+
+	bytes = min(srx->fpdu_part_rem, srx->skb_new);
+
+	if (mem_p->mem_obj == NULL)
+		rv = siw_rx_kva(srx, (void *)(sge->laddr + wqe->processed),
+				bytes);
+	else if (!mem_p->is_pbl)
+		rv = siw_rx_umem(srx, mem_p->umem, sge->laddr + wqe->processed,
+				 bytes);
+	else
+		rv = siw_rx_pbl(srx, &frx->pbl_idx, mem_p,
+				sge->laddr + wqe->processed, bytes);
+	if (rv != bytes) {
+		wqe->wc_status = SIW_WC_GENERAL_ERR;
+		rv = -EINVAL;
+		goto error_term;
+	}
+	srx->fpdu_part_rem -= rv;
+	srx->fpdu_part_rcvd += rv;
+	wqe->processed += rv;
+
+	if (!srx->fpdu_part_rem) {
+		srx->ddp_to += srx->fpdu_part_rcvd;
+		return 0;
+	}
+	return -EAGAIN;
+
+error_term:
+	siw_init_terminate(qp, TERM_ERROR_LAYER_DDP, DDP_ETYPE_CATASTROPHIC,
+			   DDP_ECODE_CATASTROPHIC, 0);
+	return rv;
+}
+
+int siw_proc_terminate(struct siw_qp *qp)
+{
+	struct siw_rx_stream *srx = &qp->rx_stream;
+	struct sk_buff *skb = srx->skb;
+	struct iwarp_terminate *term = &srx->hdr.terminate;
+	union iwarp_hdr term_info;
+	u8 *infop = (u8 *)&term_info;
+	enum rdma_opcode op;
+	u16 to_copy = sizeof(struct iwarp_ctrl);
+
+	pr_warn("siw: got TERMINATE. layer %d, type %d, code %d\n",
+		__rdmap_term_layer(term), __rdmap_term_etype(term),
+		__rdmap_term_ecode(term));
+
+	if (be32_to_cpu(term->ddp_qn) != RDMAP_UNTAGGED_QN_TERMINATE ||
+	    be32_to_cpu(term->ddp_msn) !=
+		    qp->rx_stream.ddp_msn[RDMAP_UNTAGGED_QN_TERMINATE] ||
+	    be32_to_cpu(term->ddp_mo) != 0) {
+		pr_warn("siw: rx bogus TERM [QN x%08x, MSN x%08x, MO x%08x]\n",
+			be32_to_cpu(term->ddp_qn), be32_to_cpu(term->ddp_msn),
+			be32_to_cpu(term->ddp_mo));
+		return -ECONNRESET;
+	}
+	/*
+	 * Receive remaining pieces of TERM if indicated
+	 */
+	if (!term->flag_m)
+		return -ECONNRESET;
+
+	/* Do not take the effort to reassemble a network fragmented
+	 * TERM message
+	 */
+	if (srx->skb_new < sizeof(struct iwarp_ctrl_tagged))
+		return -ECONNRESET;
+
+	memset(infop, 0, sizeof(term_info));
+
+	skb_copy_bits(skb, srx->skb_offset, infop, to_copy);
+
+	op = __rdmap_get_opcode(&term_info.ctrl);
+	if (op >= RDMAP_TERMINATE)
+		goto out;
+
+	infop += to_copy;
+	srx->skb_offset += to_copy;
+	srx->skb_new -= to_copy;
+	srx->skb_copied += to_copy;
+	srx->fpdu_part_rcvd += to_copy;
+	srx->fpdu_part_rem -= to_copy;
+
+	to_copy = iwarp_pktinfo[op].hdr_len - to_copy;
+
+	/* Again, no network fragmented TERM's */
+	if (to_copy + MPA_CRC_SIZE > srx->skb_new)
+		return -ECONNRESET;
+
+	skb_copy_bits(skb, srx->skb_offset, infop, to_copy);
+
+	if (term->flag_r) {
+		siw_dbg_qp(qp, "TERM reports RDMAP hdr type %u, len %u (%s)\n",
+			   op, be16_to_cpu(term_info.ctrl.mpa_len),
+			   term->flag_m ? "valid" : "invalid");
+	} else if (term->flag_d) {
+		siw_dbg_qp(qp, "TERM reports DDP hdr type %u, len %u (%s)\n",
+			   op, be16_to_cpu(term_info.ctrl.mpa_len),
+			   term->flag_m ? "valid" : "invalid");
+	}
+out:
+	srx->skb_new -= to_copy;
+	srx->skb_offset += to_copy;
+	srx->skb_copied += to_copy;
+	srx->fpdu_part_rcvd += to_copy;
+	srx->fpdu_part_rem -= to_copy;
+
+	return -ECONNRESET;
+}
+
+static int siw_get_trailer(struct siw_qp *qp, struct siw_rx_stream *srx)
+{
+	struct sk_buff *skb = srx->skb;
+	u8 *tbuf = (u8 *)&srx->trailer.crc - srx->pad;
+	__wsum crc_in, crc_own = 0;
+
+	siw_dbg_qp(qp, "expected %d, available %d, pad %u\n",
+		   srx->fpdu_part_rem, srx->skb_new, srx->pad);
+
+	if (srx->skb_new < srx->fpdu_part_rem)
+		return -EAGAIN;
+
+	skb_copy_bits(skb, srx->skb_offset, tbuf, srx->fpdu_part_rem);
+
+	if (srx->mpa_crc_hd && srx->pad)
+		crypto_shash_update(srx->mpa_crc_hd, tbuf, srx->pad);
+
+	srx->skb_new -= srx->fpdu_part_rem;
+	srx->skb_offset += srx->fpdu_part_rem;
+	srx->skb_copied += srx->fpdu_part_rem;
+
+	if (!srx->mpa_crc_hd)
+		return 0;
+
+	/*
+	 * CRC32 is computed, transmitted and received directly in NBO,
+	 * so there's never a reason to convert byte order.
+	 */
+	crypto_shash_final(srx->mpa_crc_hd, (u8 *)&crc_own);
+	crc_in = (__force __wsum)srx->trailer.crc;
+
+	if (unlikely(crc_in != crc_own)) {
+		pr_warn("siw: crc error. in: %08x, own %08x, op %u\n",
+			crc_in, crc_own, qp->rx_stream.rdmap_op);
+
+		siw_init_terminate(qp, TERM_ERROR_LAYER_LLP,
+				   LLP_ETYPE_MPA,
+				   LLP_ECODE_RECEIVED_CRC, 0);
+		return -EINVAL;
+	}
+	return 0;
+}
+
+#define MIN_DDP_HDR sizeof(struct iwarp_ctrl_tagged)
+
+static int siw_get_hdr(struct siw_rx_stream *srx)
+{
+	struct sk_buff *skb = srx->skb;
+	struct siw_qp *qp = rx_qp(srx);
+	struct iwarp_ctrl *c_hdr = &srx->hdr.ctrl;
+	struct siw_rx_fpdu *frx;
+	u8 opcode;
+	int bytes;
+
+	if (srx->fpdu_part_rcvd < MIN_DDP_HDR) {
+		/*
+		 * copy a mimimum sized (tagged) DDP frame control part
+		 */
+		bytes = min_t(int, srx->skb_new,
+			      MIN_DDP_HDR - srx->fpdu_part_rcvd);
+
+		skb_copy_bits(skb, srx->skb_offset,
+			      (char *)c_hdr + srx->fpdu_part_rcvd, bytes);
+
+		srx->fpdu_part_rcvd += bytes;
+
+		srx->skb_new -= bytes;
+		srx->skb_offset += bytes;
+		srx->skb_copied += bytes;
+
+		if (srx->fpdu_part_rcvd < MIN_DDP_HDR)
+			return -EAGAIN;
+
+		if (unlikely(__ddp_get_version(c_hdr) != DDP_VERSION)) {
+			enum ddp_etype etype;
+			enum ddp_ecode ecode;
+
+			pr_warn("siw: received ddp version unsupported %d\n",
+				__ddp_get_version(c_hdr));
+
+			if (c_hdr->ddp_rdmap_ctrl & DDP_FLAG_TAGGED) {
+				etype = DDP_ETYPE_TAGGED_BUF;
+				ecode = DDP_ECODE_T_VERSION;
+			} else {
+				etype = DDP_ETYPE_UNTAGGED_BUF;
+				ecode = DDP_ECODE_UT_VERSION;
+			}
+			siw_init_terminate(rx_qp(srx), TERM_ERROR_LAYER_DDP,
+					   etype, ecode, 0);
+			return -EINVAL;
+		}
+		if (unlikely(__rdmap_get_version(c_hdr) != RDMAP_VERSION)) {
+			pr_warn("siw: received rdmap version unsupported %d\n",
+				__rdmap_get_version(c_hdr));
+
+			siw_init_terminate(rx_qp(srx), TERM_ERROR_LAYER_RDMAP,
+					   RDMAP_ETYPE_REMOTE_OPERATION,
+					   RDMAP_ECODE_VERSION, 0);
+			return -EINVAL;
+		}
+		opcode = __rdmap_get_opcode(c_hdr);
+
+		if (opcode > RDMAP_TERMINATE) {
+			pr_warn("siw: received unknown packet type %u\n",
+				opcode);
+
+			siw_init_terminate(rx_qp(srx), TERM_ERROR_LAYER_RDMAP,
+					   RDMAP_ETYPE_REMOTE_OPERATION,
+					   RDMAP_ECODE_OPCODE, 0);
+			return -EINVAL;
+		}
+		siw_dbg_qp(rx_qp(srx), "new header, opcode %u\n", opcode);
+	} else {
+		opcode = __rdmap_get_opcode(c_hdr);
+	}
+	set_rx_fpdu_context(qp, opcode);
+	frx = qp->rx_fpdu;
+
+	/*
+	 * Figure out len of current hdr: variable length of
+	 * iwarp hdr may force us to copy hdr information in
+	 * two steps. Only tagged DDP messages are already
+	 * completely received.
+	 */
+	if (iwarp_pktinfo[opcode].hdr_len > sizeof(struct iwarp_ctrl_tagged)) {
+		bytes = iwarp_pktinfo[opcode].hdr_len - MIN_DDP_HDR;
+
+		if (srx->skb_new < bytes)
+			return -EAGAIN;
+
+		skb_copy_bits(skb, srx->skb_offset,
+			      (char *)c_hdr + srx->fpdu_part_rcvd, bytes);
+
+		srx->fpdu_part_rcvd += bytes;
+
+		srx->skb_new -= bytes;
+		srx->skb_offset += bytes;
+		srx->skb_copied += bytes;
+	}
+
+	/*
+	 * DDP/RDMAP header receive completed. Check if the current
+	 * DDP segment starts a new RDMAP message or continues a previously
+	 * started RDMAP message.
+	 *
+	 * Alternating reception of DDP segments (or FPDUs) from incomplete
+	 * tagged and untagged RDMAP messages is supported, as long as
+	 * the current tagged or untagged message gets eventually completed
+	 * w/o intersection from another message of the same type
+	 * (tagged/untagged). E.g., a WRITE can get intersected by a SEND,
+	 * but not by a READ RESPONSE etc.
+	 */
+	if (srx->mpa_crc_hd) {
+		/*
+		 * Restart CRC computation
+		 */
+		crypto_shash_init(srx->mpa_crc_hd);
+		crypto_shash_update(srx->mpa_crc_hd, (u8 *)c_hdr,
+				    srx->fpdu_part_rcvd);
+	}
+	if (frx->more_ddp_segs) {
+		frx->first_ddp_seg = 0;
+		if (frx->prev_rdmap_op != opcode) {
+			pr_warn("siw: packet intersection: %u : %u\n",
+				frx->prev_rdmap_op, opcode);
+			/*
+			 * The last inbound RDMA operation of same type
+			 * (tagged or untagged) is left unfinished.
+			 * To complete it in error, make it the current
+			 * operation again, even with the header already
+			 * overwritten. For error handling, only the opcode
+			 * and current rx context are relevant.
+			 */
+			set_rx_fpdu_context(qp, frx->prev_rdmap_op);
+			__rdmap_set_opcode(c_hdr, frx->prev_rdmap_op);
+			return -EPROTO;
+		}
+	} else {
+		frx->prev_rdmap_op = opcode;
+		frx->first_ddp_seg = 1;
+	}
+	frx->more_ddp_segs = c_hdr->ddp_rdmap_ctrl & DDP_FLAG_LAST ? 0 : 1;
+
+	return 0;
+}
+
+static int siw_check_tx_fence(struct siw_qp *qp)
+{
+	struct siw_wqe *tx_waiting = tx_wqe(qp);
+	struct siw_sqe *rreq;
+	int resume_tx = 0, rv = 0;
+	unsigned long flags;
+
+	spin_lock_irqsave(&qp->orq_lock, flags);
+
+	rreq = orq_get_current(qp);
+
+	/* free current orq entry */
+	WRITE_ONCE(rreq->flags, 0);
+
+	if (qp->tx_ctx.orq_fence) {
+		if (unlikely(tx_waiting->wr_status != SIW_WR_QUEUED)) {
+			pr_warn("siw: [QP %u]: fence resume: bad status %d\n",
+				qp_id(qp), tx_waiting->wr_status);
+			rv = -EPROTO;
+			goto out;
+		}
+		/* resume SQ processing */
+		if (tx_waiting->sqe.opcode == SIW_OP_READ ||
+		    tx_waiting->sqe.opcode == SIW_OP_READ_LOCAL_INV) {
+			rreq = orq_get_tail(qp);
+			if (unlikely(!rreq)) {
+				pr_warn("siw: [QP %u]: no ORQE\n", qp_id(qp));
+				rv = -EPROTO;
+				goto out;
+			}
+			siw_read_to_orq(rreq, &tx_waiting->sqe);
+
+			qp->orq_put++;
+			qp->tx_ctx.orq_fence = 0;
+			resume_tx = 1;
+
+		} else if (siw_orq_empty(qp)) {
+			qp->tx_ctx.orq_fence = 0;
+			resume_tx = 1;
+		} else {
+			pr_warn("siw: [QP %u]: fence resume: orq idx: %d:%d\n",
+				qp_id(qp), qp->orq_get, qp->orq_put);
+			rv = -EPROTO;
+		}
+	}
+	qp->orq_get++;
+out:
+	spin_unlock_irqrestore(&qp->orq_lock, flags);
+
+	if (resume_tx)
+		rv = siw_sq_start(qp);
+
+	return rv;
+}
+
+/*
+ * siw_rdmap_complete()
+ *
+ * Complete processing of an RDMA message after receiving all
+ * DDP segmens or ABort processing after encountering error case.
+ *
+ *   o SENDs + RRESPs will need for completion,
+ *   o RREQs need for  READ RESPONSE initialization
+ *   o WRITEs need memory dereferencing
+ *
+ * TODO: Failed WRITEs need local error to be surfaced.
+ */
+static int siw_rdmap_complete(struct siw_qp *qp, int error)
+{
+	struct siw_rx_stream *srx = &qp->rx_stream;
+	struct siw_wqe *wqe = rx_wqe(qp->rx_fpdu);
+	enum siw_wc_status wc_status = wqe->wc_status;
+	u8 opcode = __rdmap_get_opcode(&srx->hdr.ctrl);
+	int rv = 0;
+
+	switch (opcode) {
+	case RDMAP_SEND_SE:
+	case RDMAP_SEND_SE_INVAL:
+		wqe->rqe.flags |= SIW_WQE_SOLICITED;
+	case RDMAP_SEND:
+	case RDMAP_SEND_INVAL:
+		if (wqe->wr_status == SIW_WR_IDLE)
+			break;
+
+		srx->ddp_msn[RDMAP_UNTAGGED_QN_SEND]++;
+
+		if (error != 0 && wc_status == SIW_WC_SUCCESS)
+			wc_status = SIW_WC_GENERAL_ERR;
+		/*
+		 * Handle STag invalidation request
+		 */
+		if (wc_status == SIW_WC_SUCCESS &&
+		    (opcode == RDMAP_SEND_INVAL ||
+		     opcode == RDMAP_SEND_SE_INVAL)) {
+			rv = siw_invalidate_stag(qp->pd, srx->inval_stag);
+			if (rv) {
+				siw_init_terminate(
+					qp, TERM_ERROR_LAYER_RDMAP,
+					rv == -EACCES ?
+						RDMAP_ETYPE_REMOTE_PROTECTION :
+						RDMAP_ETYPE_REMOTE_OPERATION,
+					RDMAP_ECODE_CANNOT_INVALIDATE, 0);
+
+				wc_status = SIW_WC_REM_INV_REQ_ERR;
+			}
+			rv = siw_rqe_complete(qp, &wqe->rqe, wqe->processed,
+					      rv ? 0 : srx->inval_stag,
+					      wc_status);
+		} else {
+			rv = siw_rqe_complete(qp, &wqe->rqe, wqe->processed,
+					      0, wc_status);
+		}
+		siw_wqe_put_mem(wqe, SIW_OP_RECEIVE);
+		break;
+
+	case RDMAP_RDMA_READ_RESP:
+		if (wqe->wr_status == SIW_WR_IDLE)
+			break;
+
+		if (error != 0) {
+			if ((srx->state == SIW_GET_HDR &&
+			     qp->rx_fpdu->first_ddp_seg) || error == -ENODATA)
+				/* possible RREQ in ORQ left untouched */
+				break;
+
+			if (wc_status == SIW_WC_SUCCESS)
+				wc_status = SIW_WC_GENERAL_ERR;
+		} else if (qp->kernel_verbs &&
+			   rx_type(wqe) == SIW_OP_READ_LOCAL_INV) {
+			/*
+			 * Handle any STag invalidation request
+			 */
+			rv = siw_invalidate_stag(qp->pd, wqe->sqe.sge[0].lkey);
+			if (rv) {
+				siw_init_terminate(qp, TERM_ERROR_LAYER_RDMAP,
+						   RDMAP_ETYPE_CATASTROPHIC,
+						   RDMAP_ECODE_UNSPECIFIED, 0);
+
+				if (wc_status == SIW_WC_SUCCESS) {
+					wc_status = SIW_WC_GENERAL_ERR;
+					error = rv;
+				}
+			}
+		}
+		/*
+		 * All errors turn the wqe into signalled.
+		 */
+		if ((wqe->sqe.flags & SIW_WQE_SIGNALLED) || error != 0)
+			rv = siw_sqe_complete(qp, &wqe->sqe, wqe->processed,
+					      wc_status);
+		siw_wqe_put_mem(wqe, SIW_OP_READ);
+
+		if (!error)
+			rv = siw_check_tx_fence(qp);
+		else
+			/* Disable current ORQ eleement */
+			WRITE_ONCE(orq_get_current(qp)->flags, 0);
+		break;
+
+	case RDMAP_RDMA_READ_REQ:
+		if (!error) {
+			rv = siw_init_rresp(qp, srx);
+			srx->ddp_msn[RDMAP_UNTAGGED_QN_RDMA_READ]++;
+		}
+		break;
+
+	case RDMAP_RDMA_WRITE:
+		if (wqe->wr_status == SIW_WR_IDLE)
+			break;
+
+		/*
+		 * Free References from memory object if
+		 * attached to receive context (inbound WRITE).
+		 * While a zero-length WRITE is allowed,
+		 * no memory reference got created.
+		 */
+		if (rx_mem(&qp->rx_tagged)) {
+			siw_mem_put(rx_mem(&qp->rx_tagged));
+			rx_mem(&qp->rx_tagged) = NULL;
+		}
+		break;
+
+	default:
+		break;
+	}
+	wqe->wr_status = SIW_WR_IDLE;
+
+	return rv;
+}
+
+/*
+ * siw_tcp_rx_data()
+ *
+ * Main routine to consume inbound TCP payload
+ *
+ * @rd_desc:	read descriptor
+ * @skb:	socket buffer
+ * @off:	offset in skb
+ * @len:	skb->len - offset : payload in skb
+ */
+int siw_tcp_rx_data(read_descriptor_t *rd_desc, struct sk_buff *skb,
+		    unsigned int off, size_t len)
+{
+	struct siw_qp *qp = rd_desc->arg.data;
+	struct siw_rx_stream *srx = &qp->rx_stream;
+	int rv;
+
+	srx->skb = skb;
+	srx->skb_new = skb->len - off;
+	srx->skb_offset = off;
+	srx->skb_copied = 0;
+
+	siw_dbg_qp(qp, "new data, len %d\n", srx->skb_new);
+
+	while (srx->skb_new) {
+		int run_completion = 1;
+
+		if (unlikely(srx->rx_suspend)) {
+			/* Do not process any more data */
+			srx->skb_copied += srx->skb_new;
+			break;
+		}
+		switch (srx->state) {
+		case SIW_GET_HDR:
+			rv = siw_get_hdr(srx);
+			if (!rv) {
+				srx->fpdu_part_rem =
+					be16_to_cpu(srx->hdr.ctrl.mpa_len) -
+					srx->fpdu_part_rcvd + MPA_HDR_SIZE;
+
+				if (srx->fpdu_part_rem)
+					srx->pad = -srx->fpdu_part_rem & 0x3;
+				else
+					srx->pad = 0;
+
+				srx->state = SIW_GET_DATA_START;
+				srx->fpdu_part_rcvd = 0;
+			}
+			break;
+
+		case SIW_GET_DATA_MORE:
+			/*
+			 * Another data fragment of the same DDP segment.
+			 * Setting first_ddp_seg = 0 avoids repeating
+			 * initializations that shall occur only once per
+			 * DDP segment.
+			 */
+			qp->rx_fpdu->first_ddp_seg = 0;
+			/* Fall through */
+
+		case SIW_GET_DATA_START:
+			/*
+			 * Headers will be checked by the opcode-specific
+			 * data receive function below.
+			 */
+			rv = iwarp_pktinfo[qp->rx_stream.rdmap_op].rx_data(qp);
+			if (!rv) {
+				int mpa_len =
+					be16_to_cpu(srx->hdr.ctrl.mpa_len)
+					+ MPA_HDR_SIZE;
+
+				srx->fpdu_part_rem = (-mpa_len & 0x3)
+						      + MPA_CRC_SIZE;
+				srx->fpdu_part_rcvd = 0;
+				srx->state = SIW_GET_TRAILER;
+			} else {
+				if (unlikely(rv == -ECONNRESET))
+					run_completion = 0;
+				else
+					srx->state = SIW_GET_DATA_MORE;
+			}
+			break;
+
+		case SIW_GET_TRAILER:
+			/*
+			 * read CRC + any padding
+			 */
+			rv = siw_get_trailer(qp, srx);
+			if (likely(!rv)) {
+				/*
+				 * FPDU completed.
+				 * complete RDMAP message if last fragment
+				 */
+				srx->state = SIW_GET_HDR;
+				srx->fpdu_part_rcvd = 0;
+
+				if (!(srx->hdr.ctrl.ddp_rdmap_ctrl &
+				      DDP_FLAG_LAST))
+					/* more frags */
+					break;
+
+				rv = siw_rdmap_complete(qp, 0);
+				run_completion = 0;
+			}
+			break;
+
+		default:
+			pr_warn("QP[%u]: RX out of state\n", qp_id(qp));
+			rv = -EPROTO;
+			run_completion = 0;
+		}
+		if (unlikely(rv != 0 && rv != -EAGAIN)) {
+			if ((srx->state > SIW_GET_HDR ||
+			     qp->rx_fpdu->more_ddp_segs) && run_completion)
+				siw_rdmap_complete(qp, rv);
+
+			siw_dbg_qp(qp, "rx error %d, rx state %d\n", rv,
+				   srx->state);
+
+			siw_qp_cm_drop(qp, 1);
+
+			break;
+		}
+		if (rv) {
+			siw_dbg_qp(qp, "fpdu fragment, state %d, missing %d\n",
+				   srx->state, srx->fpdu_part_rem);
+			break;
+		}
+	}
+	return srx->skb_copied;
+}
diff --git a/drivers/infiniband/sw/siw/siw_qp_tx.c b/drivers/infiniband/sw/siw/siw_qp_tx.c
new file mode 100644
index 000000000000..5e926fac51db
--- /dev/null
+++ b/drivers/infiniband/sw/siw/siw_qp_tx.c
@@ -0,0 +1,1269 @@
+// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/net.h>
+#include <linux/scatterlist.h>
+#include <linux/highmem.h>
+#include <net/tcp.h>
+
+#include <rdma/iw_cm.h>
+#include <rdma/ib_verbs.h>
+#include <rdma/ib_user_verbs.h>
+
+#include "siw.h"
+#include "siw_verbs.h"
+#include "siw_mem.h"
+
+#define MAX_HDR_INLINE					\
+	(((uint32_t)(sizeof(struct siw_rreq_pkt) -	\
+		     sizeof(struct iwarp_send))) & 0xF8)
+
+static struct page *siw_get_pblpage(struct siw_mem *mem, u64 addr, int *idx)
+{
+	struct siw_pbl *pbl = mem->pbl;
+	u64 offset = addr - mem->va;
+	u64 paddr = siw_pbl_get_buffer(pbl, offset, NULL, idx);
+
+	if (paddr)
+		return virt_to_page(paddr);
+
+	return NULL;
+}
+
+/*
+ * Copy short payload at provided destination payload address
+ */
+static int siw_try_1seg(struct siw_iwarp_tx *c_tx, u64 paddr)
+{
+	struct siw_wqe *wqe = &c_tx->wqe_active;
+	struct siw_sge *sge = &wqe->sqe.sge[0];
+	u32 bytes = sge->length;
+
+	if (bytes > MAX_HDR_INLINE || wqe->sqe.num_sge != 1)
+		return MAX_HDR_INLINE + 1;
+
+	if (!bytes)
+		return 0;
+
+	if (tx_flags(wqe) & SIW_WQE_INLINE) {
+		memcpy((void *)paddr, &wqe->sqe.sge[1], bytes);
+	} else {
+		struct siw_mem *mem = wqe->mem[0];
+
+		if (!mem->mem_obj) {
+			/* Kernel client using kva */
+			memcpy((void *)paddr, (void *)sge->laddr, bytes);
+		} else if (c_tx->in_syscall) {
+			if (copy_from_user((void *)paddr,
+					   (const void __user *)sge->laddr,
+					   bytes))
+				return -EFAULT;
+		} else {
+			unsigned int off = sge->laddr & ~PAGE_MASK;
+			struct page *p;
+			char *buffer;
+			int pbl_idx = 0;
+
+			if (!mem->is_pbl)
+				p = siw_get_upage(mem->umem, sge->laddr);
+			else
+				p = siw_get_pblpage(mem, sge->laddr, &pbl_idx);
+
+			if (unlikely(!p))
+				return -EFAULT;
+
+			buffer = kmap_atomic(p);
+
+			if (likely(PAGE_SIZE - off >= bytes)) {
+				memcpy((void *)paddr, buffer + off, bytes);
+				kunmap_atomic(buffer);
+			} else {
+				unsigned long part = bytes - (PAGE_SIZE - off);
+
+				memcpy((void *)paddr, buffer + off, part);
+				kunmap_atomic(buffer);
+
+				if (!mem->is_pbl)
+					p = siw_get_upage(mem->umem,
+							  sge->laddr + part);
+				else
+					p = siw_get_pblpage(mem,
+							    sge->laddr + part,
+							    &pbl_idx);
+				if (unlikely(!p))
+					return -EFAULT;
+
+				buffer = kmap_atomic(p);
+				memcpy((void *)(paddr + part), buffer,
+				       bytes - part);
+				kunmap_atomic(buffer);
+			}
+		}
+	}
+	return (int)bytes;
+}
+
+#define PKT_FRAGMENTED 1
+#define PKT_COMPLETE 0
+
+/*
+ * siw_qp_prepare_tx()
+ *
+ * Prepare tx state for sending out one fpdu. Builds complete pkt
+ * if no user data or only immediate data are present.
+ *
+ * returns PKT_COMPLETE if complete pkt built, PKT_FRAGMENTED otherwise.
+ */
+static int siw_qp_prepare_tx(struct siw_iwarp_tx *c_tx)
+{
+	struct siw_wqe *wqe = &c_tx->wqe_active;
+	char *crc = NULL;
+	int data = 0;
+
+	switch (tx_type(wqe)) {
+	case SIW_OP_READ:
+	case SIW_OP_READ_LOCAL_INV:
+		memcpy(&c_tx->pkt.ctrl,
+		       &iwarp_pktinfo[RDMAP_RDMA_READ_REQ].ctrl,
+		       sizeof(struct iwarp_ctrl));
+
+		c_tx->pkt.rreq.rsvd = 0;
+		c_tx->pkt.rreq.ddp_qn = htonl(RDMAP_UNTAGGED_QN_RDMA_READ);
+		c_tx->pkt.rreq.ddp_msn =
+			htonl(++c_tx->ddp_msn[RDMAP_UNTAGGED_QN_RDMA_READ]);
+		c_tx->pkt.rreq.ddp_mo = 0;
+		c_tx->pkt.rreq.sink_stag = htonl(wqe->sqe.sge[0].lkey);
+		c_tx->pkt.rreq.sink_to =
+			cpu_to_be64(wqe->sqe.sge[0].laddr);
+		c_tx->pkt.rreq.source_stag = htonl(wqe->sqe.rkey);
+		c_tx->pkt.rreq.source_to = cpu_to_be64(wqe->sqe.raddr);
+		c_tx->pkt.rreq.read_size = htonl(wqe->sqe.sge[0].length);
+
+		c_tx->ctrl_len = sizeof(struct iwarp_rdma_rreq);
+		crc = (char *)&c_tx->pkt.rreq_pkt.crc;
+		break;
+
+	case SIW_OP_SEND:
+		if (tx_flags(wqe) & SIW_WQE_SOLICITED)
+			memcpy(&c_tx->pkt.ctrl,
+			       &iwarp_pktinfo[RDMAP_SEND_SE].ctrl,
+			       sizeof(struct iwarp_ctrl));
+		else
+			memcpy(&c_tx->pkt.ctrl, &iwarp_pktinfo[RDMAP_SEND].ctrl,
+			       sizeof(struct iwarp_ctrl));
+
+		c_tx->pkt.send.ddp_qn = RDMAP_UNTAGGED_QN_SEND;
+		c_tx->pkt.send.ddp_msn =
+			htonl(++c_tx->ddp_msn[RDMAP_UNTAGGED_QN_SEND]);
+		c_tx->pkt.send.ddp_mo = 0;
+
+		c_tx->pkt.send_inv.inval_stag = 0;
+
+		c_tx->ctrl_len = sizeof(struct iwarp_send);
+
+		crc = (char *)&c_tx->pkt.send_pkt.crc;
+		data = siw_try_1seg(c_tx, (u64)crc);
+		break;
+
+	case SIW_OP_SEND_REMOTE_INV:
+		if (tx_flags(wqe) & SIW_WQE_SOLICITED)
+			memcpy(&c_tx->pkt.ctrl,
+			       &iwarp_pktinfo[RDMAP_SEND_SE_INVAL].ctrl,
+			       sizeof(struct iwarp_ctrl));
+		else
+			memcpy(&c_tx->pkt.ctrl,
+			       &iwarp_pktinfo[RDMAP_SEND_INVAL].ctrl,
+			       sizeof(struct iwarp_ctrl));
+
+		c_tx->pkt.send.ddp_qn = RDMAP_UNTAGGED_QN_SEND;
+		c_tx->pkt.send.ddp_msn =
+			htonl(++c_tx->ddp_msn[RDMAP_UNTAGGED_QN_SEND]);
+		c_tx->pkt.send.ddp_mo = 0;
+
+		c_tx->pkt.send_inv.inval_stag = cpu_to_be32(wqe->sqe.rkey);
+
+		c_tx->ctrl_len = sizeof(struct iwarp_send_inv);
+
+		crc = (char *)&c_tx->pkt.send_pkt.crc;
+		data = siw_try_1seg(c_tx, (u64)crc);
+		break;
+
+	case SIW_OP_WRITE:
+		memcpy(&c_tx->pkt.ctrl, &iwarp_pktinfo[RDMAP_RDMA_WRITE].ctrl,
+		       sizeof(struct iwarp_ctrl));
+
+		c_tx->pkt.rwrite.sink_stag = htonl(wqe->sqe.rkey);
+		c_tx->pkt.rwrite.sink_to = cpu_to_be64(wqe->sqe.raddr);
+		c_tx->ctrl_len = sizeof(struct iwarp_rdma_write);
+
+		crc = (char *)&c_tx->pkt.write_pkt.crc;
+		data = siw_try_1seg(c_tx, (u64)crc);
+		break;
+
+	case SIW_OP_READ_RESPONSE:
+		memcpy(&c_tx->pkt.ctrl,
+		       &iwarp_pktinfo[RDMAP_RDMA_READ_RESP].ctrl,
+		       sizeof(struct iwarp_ctrl));
+
+		/* NBO */
+		c_tx->pkt.rresp.sink_stag = cpu_to_be32(wqe->sqe.rkey);
+		c_tx->pkt.rresp.sink_to = cpu_to_be64(wqe->sqe.raddr);
+
+		c_tx->ctrl_len = sizeof(struct iwarp_rdma_rresp);
+
+		crc = (char *)&c_tx->pkt.write_pkt.crc;
+		data = siw_try_1seg(c_tx, (u64)crc);
+		break;
+
+	default:
+		siw_dbg_qp(tx_qp(c_tx), "stale wqe type %d\n", tx_type(wqe));
+		return -EOPNOTSUPP;
+	}
+	if (unlikely(data < 0))
+		return data;
+
+	c_tx->ctrl_sent = 0;
+
+	if (data <= MAX_HDR_INLINE) {
+		if (data) {
+			wqe->processed = data;
+
+			c_tx->pkt.ctrl.mpa_len =
+				htons(c_tx->ctrl_len + data - MPA_HDR_SIZE);
+
+			/* Add pad, if needed */
+			data += -(int)data & 0x3;
+			/* advance CRC location after payload */
+			crc += data;
+			c_tx->ctrl_len += data;
+
+			if (!(c_tx->pkt.ctrl.ddp_rdmap_ctrl & DDP_FLAG_TAGGED))
+				c_tx->pkt.c_untagged.ddp_mo = 0;
+			else
+				c_tx->pkt.c_tagged.ddp_to =
+					cpu_to_be64(wqe->sqe.raddr);
+		}
+
+		*(u32 *)crc = 0;
+		/*
+		 * Do complete CRC if enabled and short packet
+		 */
+		if (c_tx->mpa_crc_hd) {
+			crypto_shash_init(c_tx->mpa_crc_hd);
+			if (crypto_shash_update(c_tx->mpa_crc_hd,
+						(u8 *)&c_tx->pkt,
+						c_tx->ctrl_len))
+				return -EINVAL;
+			crypto_shash_final(c_tx->mpa_crc_hd, (u8 *)crc);
+		}
+		c_tx->ctrl_len += MPA_CRC_SIZE;
+
+		return PKT_COMPLETE;
+	}
+	c_tx->ctrl_len += MPA_CRC_SIZE;
+	c_tx->sge_idx = 0;
+	c_tx->sge_off = 0;
+	c_tx->pbl_idx = 0;
+
+	/*
+	 * Allow direct sending out of user buffer if WR is non signalled
+	 * and payload is over threshold.
+	 * Per RDMA verbs, the application should not change the send buffer
+	 * until the work completed. In iWarp, work completion is only
+	 * local delivery to TCP. TCP may reuse the buffer for
+	 * retransmission. Changing unsent data also breaks the CRC,
+	 * if applied.
+	 */
+	if (c_tx->zcopy_tx && wqe->bytes >= SENDPAGE_THRESH &&
+	    !(tx_flags(wqe) & SIW_WQE_SIGNALLED))
+		c_tx->use_sendpage = 1;
+	else
+		c_tx->use_sendpage = 0;
+
+	return PKT_FRAGMENTED;
+}
+
+/*
+ * Send out one complete control type FPDU, or header of FPDU carrying
+ * data. Used for fixed sized packets like Read.Requests or zero length
+ * SENDs, WRITEs, READ.Responses, or header only.
+ */
+static int siw_tx_ctrl(struct siw_iwarp_tx *c_tx, struct socket *s,
+			      int flags)
+{
+	struct msghdr msg = { .msg_flags = flags };
+	struct kvec iov = { .iov_base =
+				    (char *)&c_tx->pkt.ctrl + c_tx->ctrl_sent,
+			    .iov_len = c_tx->ctrl_len - c_tx->ctrl_sent };
+
+	int rv = kernel_sendmsg(s, &msg, &iov, 1,
+				c_tx->ctrl_len - c_tx->ctrl_sent);
+
+	if (rv >= 0) {
+		c_tx->ctrl_sent += rv;
+
+		if (c_tx->ctrl_sent == c_tx->ctrl_len)
+			rv = 0;
+		else
+			rv = -EAGAIN;
+	}
+	return rv;
+}
+
+/*
+ * 0copy TCP transmit interface: Use do_tcp_sendpages.
+ *
+ * Using sendpage to push page by page appears to be less efficient
+ * than using sendmsg, even if data are copied.
+ *
+ * A general performance limitation might be the extra four bytes
+ * trailer checksum segment to be pushed after user data.
+ */
+static int siw_tcp_sendpages(struct socket *s, struct page **page, int offset,
+			     size_t size)
+{
+	struct sock *sk = s->sk;
+	int i = 0, rv = 0, sent = 0,
+	    flags = MSG_MORE | MSG_DONTWAIT | MSG_SENDPAGE_NOTLAST;
+
+	while (size) {
+		size_t bytes = min_t(size_t, PAGE_SIZE - offset, size);
+
+		if (size + offset <= PAGE_SIZE)
+			flags = MSG_MORE | MSG_DONTWAIT;
+
+		tcp_rate_check_app_limited(sk);
+try_page_again:
+		lock_sock(sk);
+		rv = do_tcp_sendpages(sk, page[i], offset, bytes, flags);
+		release_sock(sk);
+
+		if (rv > 0) {
+			size -= rv;
+			sent += rv;
+			if (rv != bytes) {
+				offset += rv;
+				bytes -= rv;
+				goto try_page_again;
+			}
+			offset = 0;
+		} else {
+			if (rv == -EAGAIN || rv == 0)
+				break;
+			return rv;
+		}
+		i++;
+	}
+	return sent;
+}
+
+/*
+ * siw_0copy_tx()
+ *
+ * Pushes list of pages to TCP socket. If pages from multiple
+ * SGE's, all referenced pages of each SGE are pushed in one
+ * shot.
+ */
+static int siw_0copy_tx(struct socket *s, struct page **page,
+			struct siw_sge *sge, unsigned int offset,
+			unsigned int size)
+{
+	int i = 0, sent = 0, rv;
+	int sge_bytes = min(sge->length - offset, size);
+
+	offset = (sge->laddr + offset) & ~PAGE_MASK;
+
+	while (sent != size) {
+		rv = siw_tcp_sendpages(s, &page[i], offset, sge_bytes);
+		if (rv >= 0) {
+			sent += rv;
+			if (size == sent || sge_bytes > rv)
+				break;
+
+			i += PAGE_ALIGN(sge_bytes + offset) >> PAGE_SHIFT;
+			sge++;
+			sge_bytes = min(sge->length, size - sent);
+			offset = sge->laddr & ~PAGE_MASK;
+		} else {
+			sent = rv;
+			break;
+		}
+	}
+	return sent;
+}
+
+#define MAX_TRAILER (MPA_CRC_SIZE + 4)
+
+static void siw_unmap_pages(struct page **pages, int hdr_len, int num_maps)
+{
+	if (hdr_len) {
+		++pages;
+		--num_maps;
+	}
+	while (num_maps-- > 0) {
+		kunmap(*pages);
+		pages++;
+	}
+}
+
+/*
+ * siw_tx_hdt() tries to push a complete packet to TCP where all
+ * packet fragments are referenced by the elements of one iovec.
+ * For the data portion, each involved page must be referenced by
+ * one extra element. All sge's data can be non-aligned to page
+ * boundaries. Two more elements are referencing iWARP header
+ * and trailer:
+ * MAX_ARRAY = 64KB/PAGE_SIZE + 1 + (2 * (SIW_MAX_SGE - 1) + HDR + TRL
+ */
+#define MAX_ARRAY ((0xffff / PAGE_SIZE) + 1 + (2 * (SIW_MAX_SGE - 1) + 2))
+
+/*
+ * Write out iov referencing hdr, data and trailer of current FPDU.
+ * Update transmit state dependent on write return status
+ */
+static int siw_tx_hdt(struct siw_iwarp_tx *c_tx, struct socket *s)
+{
+	struct siw_wqe *wqe = &c_tx->wqe_active;
+	struct siw_sge *sge = &wqe->sqe.sge[c_tx->sge_idx];
+	struct kvec iov[MAX_ARRAY];
+	struct page *page_array[MAX_ARRAY];
+	struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_EOR };
+
+	int seg = 0, do_crc = c_tx->do_crc, is_kva = 0, rv;
+	unsigned int data_len = c_tx->bytes_unsent, hdr_len = 0, trl_len = 0,
+		     sge_off = c_tx->sge_off, sge_idx = c_tx->sge_idx,
+		     pbl_idx = c_tx->pbl_idx;
+
+	if (c_tx->state == SIW_SEND_HDR) {
+		if (c_tx->use_sendpage) {
+			rv = siw_tx_ctrl(c_tx, s, MSG_DONTWAIT | MSG_MORE);
+			if (rv)
+				goto done;
+
+			c_tx->state = SIW_SEND_DATA;
+		} else {
+			iov[0].iov_base =
+				(char *)&c_tx->pkt.ctrl + c_tx->ctrl_sent;
+			iov[0].iov_len = hdr_len =
+				c_tx->ctrl_len - c_tx->ctrl_sent;
+			seg = 1;
+		}
+	}
+
+	wqe->processed += data_len;
+
+	while (data_len) { /* walk the list of SGE's */
+		unsigned int sge_len = min(sge->length - sge_off, data_len);
+		unsigned int fp_off = (sge->laddr + sge_off) & ~PAGE_MASK;
+		struct siw_mem *mem;
+
+		if (!(tx_flags(wqe) & SIW_WQE_INLINE)) {
+			mem = wqe->mem[sge_idx];
+			if (!mem->mem_obj)
+				is_kva = 1;
+		} else {
+			is_kva = 1;
+		}
+		if (is_kva && !c_tx->use_sendpage) {
+			/*
+			 * tx from kernel virtual address: either inline data
+			 * or memory region with assigned kernel buffer
+			 */
+			iov[seg].iov_base = (void *)(sge->laddr + sge_off);
+			iov[seg].iov_len = sge_len;
+
+			if (do_crc)
+				crypto_shash_update(c_tx->mpa_crc_hd,
+						    iov[seg].iov_base,
+						    sge_len);
+			sge_off += sge_len;
+			data_len -= sge_len;
+			seg++;
+			goto sge_done;
+		}
+
+		while (sge_len) {
+			size_t plen = min((int)PAGE_SIZE - fp_off, sge_len);
+
+			if (!is_kva) {
+				struct page *p;
+
+				if (mem->is_pbl)
+					p = siw_get_pblpage(
+						mem, sge->laddr + sge_off,
+						&pbl_idx);
+				else
+					p = siw_get_upage(mem->umem,
+							  sge->laddr + sge_off);
+				if (unlikely(!p)) {
+					if (hdr_len)
+						seg--;
+					if (!c_tx->use_sendpage && seg) {
+						siw_unmap_pages(page_array,
+								hdr_len, seg);
+					}
+					wqe->processed -= c_tx->bytes_unsent;
+					rv = -EFAULT;
+					goto done_crc;
+				}
+				page_array[seg] = p;
+
+				if (!c_tx->use_sendpage) {
+					iov[seg].iov_base = kmap(p) + fp_off;
+					iov[seg].iov_len = plen;
+					if (do_crc)
+						crypto_shash_update(
+							c_tx->mpa_crc_hd,
+							iov[seg].iov_base,
+							plen);
+				} else if (do_crc)
+					crypto_shash_update(
+						c_tx->mpa_crc_hd,
+						page_address(p) + fp_off,
+						plen);
+			} else {
+				u64 pa = ((sge->laddr + sge_off) & PAGE_MASK);
+
+				page_array[seg] = virt_to_page(pa);
+				if (do_crc)
+					crypto_shash_update(
+						c_tx->mpa_crc_hd,
+						(void *)(sge->laddr + sge_off),
+						plen);
+			}
+
+			sge_len -= plen;
+			sge_off += plen;
+			data_len -= plen;
+			fp_off = 0;
+
+			if (++seg > (int)MAX_ARRAY) {
+				siw_dbg_qp(tx_qp(c_tx), "to many fragments\n");
+				if (!is_kva && !c_tx->use_sendpage) {
+					siw_unmap_pages(page_array, hdr_len,
+							seg - 1);
+				}
+				wqe->processed -= c_tx->bytes_unsent;
+				rv = -EMSGSIZE;
+				goto done_crc;
+			}
+		}
+sge_done:
+		/* Update SGE variables at end of SGE */
+		if (sge_off == sge->length &&
+		    (data_len != 0 || wqe->processed < wqe->bytes)) {
+			sge_idx++;
+			sge++;
+			sge_off = 0;
+		}
+	}
+	/* trailer */
+	if (likely(c_tx->state != SIW_SEND_TRAILER)) {
+		iov[seg].iov_base = &c_tx->trailer.pad[4 - c_tx->pad];
+		iov[seg].iov_len = trl_len = MAX_TRAILER - (4 - c_tx->pad);
+	} else {
+		iov[seg].iov_base = &c_tx->trailer.pad[c_tx->ctrl_sent];
+		iov[seg].iov_len = trl_len = MAX_TRAILER - c_tx->ctrl_sent;
+	}
+
+	if (c_tx->pad) {
+		*(u32 *)c_tx->trailer.pad = 0;
+		if (do_crc)
+			crypto_shash_update(c_tx->mpa_crc_hd,
+				(u8 *)&c_tx->trailer.crc - c_tx->pad,
+				c_tx->pad);
+	}
+	if (!c_tx->mpa_crc_hd)
+		c_tx->trailer.crc = 0;
+	else if (do_crc)
+		crypto_shash_final(c_tx->mpa_crc_hd, (u8 *)&c_tx->trailer.crc);
+
+	data_len = c_tx->bytes_unsent;
+
+	if (c_tx->use_sendpage) {
+		rv = siw_0copy_tx(s, page_array, &wqe->sqe.sge[c_tx->sge_idx],
+				  c_tx->sge_off, data_len);
+		if (rv == data_len) {
+			rv = kernel_sendmsg(s, &msg, &iov[seg], 1, trl_len);
+			if (rv > 0)
+				rv += data_len;
+			else
+				rv = data_len;
+		}
+	} else {
+		rv = kernel_sendmsg(s, &msg, iov, seg + 1,
+				    hdr_len + data_len + trl_len);
+		if (!is_kva)
+			siw_unmap_pages(page_array, hdr_len, seg);
+	}
+	if (rv < (int)hdr_len) {
+		/* Not even complete hdr pushed or negative rv */
+		wqe->processed -= data_len;
+		if (rv >= 0) {
+			c_tx->ctrl_sent += rv;
+			rv = -EAGAIN;
+		}
+		goto done_crc;
+	}
+	rv -= hdr_len;
+
+	if (rv >= (int)data_len) {
+		/* all user data pushed to TCP or no data to push */
+		if (data_len > 0 && wqe->processed < wqe->bytes) {
+			/* Save the current state for next tx */
+			c_tx->sge_idx = sge_idx;
+			c_tx->sge_off = sge_off;
+			c_tx->pbl_idx = pbl_idx;
+		}
+		rv -= data_len;
+
+		if (rv == trl_len) /* all pushed */
+			rv = 0;
+		else {
+			c_tx->state = SIW_SEND_TRAILER;
+			c_tx->ctrl_len = MAX_TRAILER;
+			c_tx->ctrl_sent = rv + 4 - c_tx->pad;
+			c_tx->bytes_unsent = 0;
+			rv = -EAGAIN;
+		}
+
+	} else if (data_len > 0) {
+		/* Maybe some user data pushed to TCP */
+		c_tx->state = SIW_SEND_DATA;
+		wqe->processed -= data_len - rv;
+
+		if (rv) {
+			/*
+			 * Some bytes out. Recompute tx state based
+			 * on old state and bytes pushed
+			 */
+			unsigned int sge_unsent;
+
+			c_tx->bytes_unsent -= rv;
+			sge = &wqe->sqe.sge[c_tx->sge_idx];
+			sge_unsent = sge->length - c_tx->sge_off;
+
+			while (sge_unsent <= rv) {
+				rv -= sge_unsent;
+				c_tx->sge_idx++;
+				c_tx->sge_off = 0;
+				sge++;
+				sge_unsent = sge->length;
+			}
+			c_tx->sge_off += rv;
+		}
+		rv = -EAGAIN;
+	}
+done_crc:
+	c_tx->do_crc = 0;
+done:
+	return rv;
+}
+
+static void siw_update_tcpseg(struct siw_iwarp_tx *c_tx,
+				     struct socket *s)
+{
+	struct tcp_sock *tp = tcp_sk(s->sk);
+
+	if (tp->gso_segs) {
+		if (c_tx->gso_seg_limit == 0)
+			c_tx->tcp_seglen = tp->mss_cache * tp->gso_segs;
+		else
+			c_tx->tcp_seglen =
+				tp->mss_cache *
+				min_t(u16, c_tx->gso_seg_limit, tp->gso_segs);
+	} else {
+		c_tx->tcp_seglen = tp->mss_cache;
+	}
+	/* Loopback may give odd numbers */
+	c_tx->tcp_seglen &= 0xfffffff8;
+}
+
+/*
+ * siw_prepare_fpdu()
+ *
+ * Prepares transmit context to send out one FPDU if FPDU will contain
+ * user data and user data are not immediate data.
+ * Computes maximum FPDU length to fill up TCP MSS if possible.
+ *
+ * @qp:		QP from which to transmit
+ * @wqe:	Current WQE causing transmission
+ *
+ * TODO: Take into account real available sendspace on socket
+ *       to avoid header misalignment due to send pausing within
+ *       fpdu transmission
+ */
+static void siw_prepare_fpdu(struct siw_qp *qp, struct siw_wqe *wqe)
+{
+	struct siw_iwarp_tx *c_tx = &qp->tx_ctx;
+	int data_len;
+
+	c_tx->ctrl_len =
+		iwarp_pktinfo[__rdmap_get_opcode(&c_tx->pkt.ctrl)].hdr_len;
+	c_tx->ctrl_sent = 0;
+
+	/*
+	 * Update target buffer offset if any
+	 */
+	if (!(c_tx->pkt.ctrl.ddp_rdmap_ctrl & DDP_FLAG_TAGGED))
+		/* Untagged message */
+		c_tx->pkt.c_untagged.ddp_mo = cpu_to_be32(wqe->processed);
+	else /* Tagged message */
+		c_tx->pkt.c_tagged.ddp_to =
+			cpu_to_be64(wqe->sqe.raddr + wqe->processed);
+
+	data_len = wqe->bytes - wqe->processed;
+	if (data_len + c_tx->ctrl_len + MPA_CRC_SIZE > c_tx->tcp_seglen) {
+		/* Trim DDP payload to fit into current TCP segment */
+		data_len = c_tx->tcp_seglen - (c_tx->ctrl_len + MPA_CRC_SIZE);
+		c_tx->pkt.ctrl.ddp_rdmap_ctrl &= ~DDP_FLAG_LAST;
+		c_tx->pad = 0;
+	} else {
+		c_tx->pkt.ctrl.ddp_rdmap_ctrl |= DDP_FLAG_LAST;
+		c_tx->pad = -data_len & 0x3;
+	}
+	c_tx->bytes_unsent = data_len;
+
+	c_tx->pkt.ctrl.mpa_len =
+		htons(c_tx->ctrl_len + data_len - MPA_HDR_SIZE);
+
+	/*
+	 * Init MPA CRC computation
+	 */
+	if (c_tx->mpa_crc_hd) {
+		crypto_shash_init(c_tx->mpa_crc_hd);
+		crypto_shash_update(c_tx->mpa_crc_hd, (u8 *)&c_tx->pkt,
+				    c_tx->ctrl_len);
+		c_tx->do_crc = 1;
+	}
+}
+
+/*
+ * siw_check_sgl_tx()
+ *
+ * Check permissions for a list of SGE's (SGL).
+ * A successful check will have all memory referenced
+ * for transmission resolved and assigned to the WQE.
+ *
+ * @pd:		Protection Domain SGL should belong to
+ * @wqe:	WQE to be checked
+ * @perms:	requested access permissions
+ *
+ */
+
+static int siw_check_sgl_tx(struct ib_pd *pd, struct siw_wqe *wqe,
+			    enum ib_access_flags perms)
+{
+	struct siw_sge *sge = &wqe->sqe.sge[0];
+	int i, len, num_sge = wqe->sqe.num_sge;
+
+	if (unlikely(num_sge > SIW_MAX_SGE))
+		return -EINVAL;
+
+	for (i = 0, len = 0; num_sge; num_sge--, i++, sge++) {
+		/*
+		 * rdma verbs: do not check stag for a zero length sge
+		 */
+		if (sge->length) {
+			int rv = siw_check_sge(pd, sge, &wqe->mem[i], perms, 0,
+					       sge->length);
+
+			if (unlikely(rv != E_ACCESS_OK))
+				return rv;
+		}
+		len += sge->length;
+	}
+	return len;
+}
+
+/*
+ * siw_qp_sq_proc_tx()
+ *
+ * Process one WQE which needs transmission on the wire.
+ */
+static int siw_qp_sq_proc_tx(struct siw_qp *qp, struct siw_wqe *wqe)
+{
+	struct siw_iwarp_tx *c_tx = &qp->tx_ctx;
+	struct socket *s = qp->attrs.sk;
+	int rv = 0, burst_len = qp->tx_ctx.burst;
+	enum rdmap_ecode ecode = RDMAP_ECODE_CATASTROPHIC_STREAM;
+
+	if (unlikely(wqe->wr_status == SIW_WR_IDLE))
+		return 0;
+
+	if (!burst_len)
+		burst_len = SQ_USER_MAXBURST;
+
+	if (wqe->wr_status == SIW_WR_QUEUED) {
+		if (!(wqe->sqe.flags & SIW_WQE_INLINE)) {
+			if (tx_type(wqe) == SIW_OP_READ_RESPONSE)
+				wqe->sqe.num_sge = 1;
+
+			if (tx_type(wqe) != SIW_OP_READ &&
+			    tx_type(wqe) != SIW_OP_READ_LOCAL_INV) {
+				/*
+				 * Reference memory to be tx'd w/o checking
+				 * access for LOCAL_READ permission, since
+				 * not defined in RDMA core.
+				 */
+				rv = siw_check_sgl_tx(qp->pd, wqe, 0);
+				if (rv < 0) {
+					if (tx_type(wqe) ==
+					    SIW_OP_READ_RESPONSE)
+						ecode = siw_rdmap_error(-rv);
+					rv = -EINVAL;
+					goto tx_error;
+				}
+				wqe->bytes = rv;
+			} else {
+				wqe->bytes = 0;
+			}
+		} else {
+			wqe->bytes = wqe->sqe.sge[0].length;
+			if (!qp->kernel_verbs) {
+				if (wqe->bytes > SIW_MAX_INLINE) {
+					rv = -EINVAL;
+					goto tx_error;
+				}
+				wqe->sqe.sge[0].laddr = (u64)&wqe->sqe.sge[1];
+			}
+		}
+		wqe->wr_status = SIW_WR_INPROGRESS;
+		wqe->processed = 0;
+
+		siw_update_tcpseg(c_tx, s);
+
+		rv = siw_qp_prepare_tx(c_tx);
+		if (rv == PKT_FRAGMENTED) {
+			c_tx->state = SIW_SEND_HDR;
+			siw_prepare_fpdu(qp, wqe);
+		} else if (rv == PKT_COMPLETE) {
+			c_tx->state = SIW_SEND_SHORT_FPDU;
+		} else {
+			goto tx_error;
+		}
+	}
+
+next_segment:
+	siw_dbg_qp(qp, "wr type %d, state %d, data %u, sent %u, id %llx\n",
+		   tx_type(wqe), wqe->wr_status, wqe->bytes, wqe->processed,
+		   wqe->sqe.id);
+
+	if (--burst_len == 0) {
+		rv = -EINPROGRESS;
+		goto tx_done;
+	}
+	if (c_tx->state == SIW_SEND_SHORT_FPDU) {
+		enum siw_opcode tx_type = tx_type(wqe);
+		unsigned int msg_flags;
+
+		if (siw_sq_empty(qp) || !siw_tcp_nagle || burst_len == 1)
+			/*
+			 * End current TCP segment, if SQ runs empty,
+			 * or siw_tcp_nagle is not set, or we bail out
+			 * soon due to no burst credit left.
+			 */
+			msg_flags = MSG_DONTWAIT;
+		else
+			msg_flags = MSG_DONTWAIT | MSG_MORE;
+
+		rv = siw_tx_ctrl(c_tx, s, msg_flags);
+
+		if (!rv && tx_type != SIW_OP_READ &&
+		    tx_type != SIW_OP_READ_LOCAL_INV)
+			wqe->processed = wqe->bytes;
+
+		goto tx_done;
+
+	} else {
+		rv = siw_tx_hdt(c_tx, s);
+	}
+	if (!rv) {
+		/*
+		 * One segment sent. Processing completed if last
+		 * segment, Do next segment otherwise.
+		 */
+		if (unlikely(c_tx->tx_suspend)) {
+			/*
+			 * Verbs, 6.4.: Try stopping sending after a full
+			 * DDP segment if the connection goes down
+			 * (== peer halfclose)
+			 */
+			rv = -ECONNABORTED;
+			goto tx_done;
+		}
+		if (c_tx->pkt.ctrl.ddp_rdmap_ctrl & DDP_FLAG_LAST) {
+			siw_dbg_qp(qp, "WQE completed\n");
+			goto tx_done;
+		}
+		c_tx->state = SIW_SEND_HDR;
+
+		siw_update_tcpseg(c_tx, s);
+
+		siw_prepare_fpdu(qp, wqe);
+		goto next_segment;
+	}
+tx_done:
+	qp->tx_ctx.burst = burst_len;
+	return rv;
+
+tx_error:
+	if (ecode != RDMAP_ECODE_CATASTROPHIC_STREAM)
+		siw_init_terminate(qp, TERM_ERROR_LAYER_RDMAP,
+				   RDMAP_ETYPE_REMOTE_PROTECTION, ecode, 1);
+	else
+		siw_init_terminate(qp, TERM_ERROR_LAYER_RDMAP,
+				   RDMAP_ETYPE_CATASTROPHIC,
+				   RDMAP_ECODE_UNSPECIFIED, 1);
+	return rv;
+}
+
+static int siw_fastreg_mr(struct ib_pd *pd, struct siw_sqe *sqe)
+{
+	struct ib_mr *base_mr = (struct ib_mr *)sqe->base_mr;
+	struct siw_device *sdev = to_siw_dev(pd->device);
+	struct siw_mem *mem = siw_mem_id2obj(sdev, sqe->rkey  >> 8);
+	int rv = 0;
+
+	siw_dbg_pd(pd, "STag 0x%08x\n", sqe->rkey);
+
+	if (unlikely(!mem || !base_mr)) {
+		pr_warn("siw: fastreg: STag 0x%08x unknown\n", sqe->rkey);
+		return -EINVAL;
+	}
+	if (unlikely(base_mr->rkey >> 8 != sqe->rkey  >> 8)) {
+		pr_warn("siw: fastreg: STag 0x%08x: bad MR\n", sqe->rkey);
+		rv = -EINVAL;
+		goto out;
+	}
+	if (unlikely(mem->pd != pd)) {
+		pr_warn("siw: fastreg: PD mismatch\n");
+		rv = -EINVAL;
+		goto out;
+	}
+	if (unlikely(mem->stag_valid)) {
+		pr_warn("siw: fastreg: STag 0x%08x already valid\n", sqe->rkey);
+		rv = -EINVAL;
+		goto out;
+	}
+	/* Refresh STag since user may have changed key part */
+	mem->stag = sqe->rkey;
+	mem->perms = sqe->access;
+
+	siw_dbg_mem(mem, "STag now valid, MR va: 0x%016llx -> 0x%016llx\n",
+		    mem->va, base_mr->iova);
+	mem->va = base_mr->iova;
+	mem->stag_valid = 1;
+out:
+	siw_mem_put(mem);
+	return rv;
+}
+
+static int siw_qp_sq_proc_local(struct siw_qp *qp, struct siw_wqe *wqe)
+{
+	int rv;
+
+	switch (tx_type(wqe)) {
+	case SIW_OP_REG_MR:
+		rv = siw_fastreg_mr(qp->pd, &wqe->sqe);
+		break;
+
+	case SIW_OP_INVAL_STAG:
+		rv = siw_invalidate_stag(qp->pd, wqe->sqe.rkey);
+		break;
+
+	default:
+		rv = -EINVAL;
+	}
+	return rv;
+}
+
+/*
+ * siw_qp_sq_process()
+ *
+ * Core TX path routine for RDMAP/DDP/MPA using a TCP kernel socket.
+ * Sends RDMAP payload for the current SQ WR @wqe of @qp in one or more
+ * MPA FPDUs, each containing a DDP segment.
+ *
+ * SQ processing may occur in user context as a result of posting
+ * new WQE's or from siw_sq_work_handler() context. Processing in
+ * user context is limited to non-kernel verbs users.
+ *
+ * SQ processing may get paused anytime, possibly in the middle of a WR
+ * or FPDU, if insufficient send space is available. SQ processing
+ * gets resumed from siw_sq_work_handler(), if send space becomes
+ * available again.
+ *
+ * Must be called with the QP state read-locked.
+ *
+ * Note:
+ * An outbound RREQ can be satisfied by the corresponding RRESP
+ * _before_ it gets assigned to the ORQ. This happens regularly
+ * in RDMA READ via loopback case. Since both outbound RREQ and
+ * inbound RRESP can be handled by the same CPU, locking the ORQ
+ * is dead-lock prone and thus not an option. With that, the
+ * RREQ gets assigned to the ORQ _before_ being sent - see
+ * siw_activate_tx() - and pulled back in case of send failure.
+ */
+int siw_qp_sq_process(struct siw_qp *qp)
+{
+	struct siw_wqe *wqe = tx_wqe(qp);
+	enum siw_opcode tx_type;
+	unsigned long flags;
+	int rv = 0;
+
+	siw_dbg_qp(qp, "enter for type %d\n", tx_type(wqe));
+
+next_wqe:
+	/*
+	 * Stop QP processing if SQ state changed
+	 */
+	if (unlikely(qp->tx_ctx.tx_suspend)) {
+		siw_dbg_qp(qp, "tx suspended\n");
+		goto done;
+	}
+	tx_type = tx_type(wqe);
+
+	if (tx_type <= SIW_OP_READ_RESPONSE)
+		rv = siw_qp_sq_proc_tx(qp, wqe);
+	else
+		rv = siw_qp_sq_proc_local(qp, wqe);
+
+	if (!rv) {
+		/*
+		 * WQE processing done
+		 */
+		switch (tx_type) {
+		case SIW_OP_SEND:
+		case SIW_OP_SEND_REMOTE_INV:
+		case SIW_OP_WRITE:
+			siw_wqe_put_mem(wqe, tx_type);
+		case SIW_OP_INVAL_STAG:
+		case SIW_OP_REG_MR:
+			if (tx_flags(wqe) & SIW_WQE_SIGNALLED)
+				siw_sqe_complete(qp, &wqe->sqe, wqe->bytes,
+						 SIW_WC_SUCCESS);
+			break;
+
+		case SIW_OP_READ:
+		case SIW_OP_READ_LOCAL_INV:
+			/*
+			 * already enqueued to ORQ queue
+			 */
+			break;
+
+		case SIW_OP_READ_RESPONSE:
+			siw_wqe_put_mem(wqe, tx_type);
+			break;
+
+		default:
+			WARN(1, "undefined WQE type %d\n", tx_type);
+			rv = -EINVAL;
+			goto done;
+		}
+
+		spin_lock_irqsave(&qp->sq_lock, flags);
+		wqe->wr_status = SIW_WR_IDLE;
+		rv = siw_activate_tx(qp);
+		spin_unlock_irqrestore(&qp->sq_lock, flags);
+
+		if (rv <= 0)
+			goto done;
+
+		goto next_wqe;
+
+	} else if (rv == -EAGAIN) {
+		siw_dbg_qp(qp, "sq paused: hd/tr %d of %d, data %d\n",
+			   qp->tx_ctx.ctrl_sent, qp->tx_ctx.ctrl_len,
+			   qp->tx_ctx.bytes_unsent);
+		rv = 0;
+		goto done;
+	} else if (rv == -EINPROGRESS) {
+		rv = siw_sq_start(qp);
+		goto done;
+	} else {
+		/*
+		 * WQE processing failed.
+		 * Verbs 8.3.2:
+		 * o It turns any WQE into a signalled WQE.
+		 * o Local catastrophic error must be surfaced
+		 * o QP must be moved into Terminate state: done by code
+		 *   doing socket state change processing
+		 *
+		 * o TODO: Termination message must be sent.
+		 * o TODO: Implement more precise work completion errors,
+		 *         see enum ib_wc_status in ib_verbs.h
+		 */
+		siw_dbg_qp(qp, "wqe type %d processing failed: %d\n",
+			   tx_type(wqe), rv);
+
+		spin_lock_irqsave(&qp->sq_lock, flags);
+		/*
+		 * RREQ may have already been completed by inbound RRESP!
+		 */
+		if (tx_type == SIW_OP_READ ||
+		    tx_type == SIW_OP_READ_LOCAL_INV) {
+			/* Cleanup pending entry in ORQ */
+			qp->orq_put--;
+			qp->orq[qp->orq_put % qp->attrs.orq_size].flags = 0;
+		}
+		spin_unlock_irqrestore(&qp->sq_lock, flags);
+		/*
+		 * immediately suspends further TX processing
+		 */
+		if (!qp->tx_ctx.tx_suspend)
+			siw_qp_cm_drop(qp, 0);
+
+		switch (tx_type) {
+		case SIW_OP_SEND:
+		case SIW_OP_SEND_REMOTE_INV:
+		case SIW_OP_SEND_WITH_IMM:
+		case SIW_OP_WRITE:
+		case SIW_OP_READ:
+		case SIW_OP_READ_LOCAL_INV:
+			siw_wqe_put_mem(wqe, tx_type);
+		case SIW_OP_INVAL_STAG:
+		case SIW_OP_REG_MR:
+			siw_sqe_complete(qp, &wqe->sqe, wqe->bytes,
+					 SIW_WC_LOC_QP_OP_ERR);
+
+			siw_qp_event(qp, IB_EVENT_QP_FATAL);
+
+			break;
+
+		case SIW_OP_READ_RESPONSE:
+			siw_dbg_qp(qp, "proc. read.response failed: %d\n", rv);
+
+			siw_qp_event(qp, IB_EVENT_QP_REQ_ERR);
+
+			siw_wqe_put_mem(wqe, SIW_OP_READ_RESPONSE);
+
+			break;
+
+		default:
+			WARN(1, "undefined WQE type %d\n", tx_type);
+			rv = -EINVAL;
+		}
+		wqe->wr_status = SIW_WR_IDLE;
+	}
+done:
+	return rv;
+}
+
+static void siw_sq_resume(struct siw_qp *qp)
+{
+	if (down_read_trylock(&qp->state_lock)) {
+		if (likely(qp->attrs.state == SIW_QP_STATE_RTS &&
+			   !qp->tx_ctx.tx_suspend)) {
+			int rv = siw_qp_sq_process(qp);
+
+			up_read(&qp->state_lock);
+
+			if (unlikely(rv < 0)) {
+				siw_dbg_qp(qp, "SQ task failed: err %d\n", rv);
+
+				if (!qp->tx_ctx.tx_suspend)
+					siw_qp_cm_drop(qp, 0);
+			}
+		} else {
+			up_read(&qp->state_lock);
+		}
+	} else {
+		siw_dbg_qp(qp, "Resume SQ while QP locked\n");
+	}
+	siw_qp_put(qp);
+}
+
+struct tx_task_t {
+	struct llist_head active;
+	wait_queue_head_t waiting;
+};
+
+static DEFINE_PER_CPU(struct tx_task_t, tx_task_g);
+
+void siw_stop_tx_thread(int nr_cpu)
+{
+	kthread_stop(siw_tx_thread[nr_cpu]);
+	wake_up(&per_cpu(tx_task_g, nr_cpu).waiting);
+}
+
+int siw_run_sq(void *data)
+{
+	const int nr_cpu = (unsigned int)(long)data;
+	struct llist_node *active;
+	struct siw_qp *qp;
+	struct tx_task_t *tx_task = &per_cpu(tx_task_g, nr_cpu);
+
+	init_llist_head(&tx_task->active);
+	init_waitqueue_head(&tx_task->waiting);
+
+	pr_info("Started siw TX thread on CPU %u\n", nr_cpu);
+
+	while (1) {
+		struct llist_node *fifo_list = NULL;
+
+		wait_event_interruptible(tx_task->waiting,
+					 !llist_empty(&tx_task->active) ||
+						 kthread_should_stop());
+
+		if (kthread_should_stop())
+			break;
+
+		active = llist_del_all(&tx_task->active);
+		/*
+		 * llist_del_all returns a list with newest entry first.
+		 * Re-order list for fairness among QP's.
+		 */
+		while (active) {
+			struct llist_node *tmp = active;
+
+			active = llist_next(active);
+			tmp->next = fifo_list;
+			fifo_list = tmp;
+		}
+		while (fifo_list) {
+			qp = container_of(fifo_list, struct siw_qp, tx_list);
+			fifo_list = llist_next(fifo_list);
+			qp->tx_list.next = NULL;
+
+			siw_sq_resume(qp);
+		}
+	}
+	active = llist_del_all(&tx_task->active);
+	if (active) {
+		llist_for_each_entry(qp, active, tx_list) {
+			qp->tx_list.next = NULL;
+			siw_sq_resume(qp);
+		}
+	}
+	pr_info("Stopped siw TX thread on CPU %u\n", nr_cpu);
+
+	return 0;
+}
+
+int siw_sq_start(struct siw_qp *qp)
+{
+	if (tx_wqe(qp)->wr_status == SIW_WR_IDLE)
+		return 0;
+
+	if (unlikely(!cpu_online(qp->tx_cpu))) {
+		siw_put_tx_cpu(qp->tx_cpu);
+		qp->tx_cpu = siw_get_tx_cpu(qp->sdev);
+		if (qp->tx_cpu < 0) {
+			pr_warn("siw: no tx cpu available\n");
+
+			return -EIO;
+		}
+	}
+	siw_qp_get(qp);
+
+	llist_add(&qp->tx_list, &per_cpu(tx_task_g, qp->tx_cpu).active);
+
+	wake_up(&per_cpu(tx_task_g, qp->tx_cpu).waiting);
+
+	return 0;
+}
diff --git a/drivers/infiniband/sw/siw/siw_verbs.c b/drivers/infiniband/sw/siw/siw_verbs.c
new file mode 100644
index 000000000000..32dc79d0e898
--- /dev/null
+++ b/drivers/infiniband/sw/siw/siw_verbs.c
@@ -0,0 +1,1760 @@
+// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+#include <linux/xarray.h>
+
+#include <rdma/iw_cm.h>
+#include <rdma/ib_verbs.h>
+#include <rdma/ib_user_verbs.h>
+#include <rdma/uverbs_ioctl.h>
+
+#include "siw.h"
+#include "siw_verbs.h"
+#include "siw_mem.h"
+
+static int ib_qp_state_to_siw_qp_state[IB_QPS_ERR + 1] = {
+	[IB_QPS_RESET] = SIW_QP_STATE_IDLE,
+	[IB_QPS_INIT] = SIW_QP_STATE_IDLE,
+	[IB_QPS_RTR] = SIW_QP_STATE_RTR,
+	[IB_QPS_RTS] = SIW_QP_STATE_RTS,
+	[IB_QPS_SQD] = SIW_QP_STATE_CLOSING,
+	[IB_QPS_SQE] = SIW_QP_STATE_TERMINATE,
+	[IB_QPS_ERR] = SIW_QP_STATE_ERROR
+};
+
+static char ib_qp_state_to_string[IB_QPS_ERR + 1][sizeof("RESET")] = {
+	[IB_QPS_RESET] = "RESET", [IB_QPS_INIT] = "INIT", [IB_QPS_RTR] = "RTR",
+	[IB_QPS_RTS] = "RTS",     [IB_QPS_SQD] = "SQD",   [IB_QPS_SQE] = "SQE",
+	[IB_QPS_ERR] = "ERR"
+};
+
+static u32 siw_create_uobj(struct siw_ucontext *uctx, void *vaddr, u32 size)
+{
+	struct siw_uobj *uobj;
+	struct xa_limit limit = XA_LIMIT(0, SIW_UOBJ_MAX_KEY);
+	u32 key;
+
+	uobj = kzalloc(sizeof(*uobj), GFP_KERNEL);
+	if (!uobj)
+		return SIW_INVAL_UOBJ_KEY;
+
+	if (xa_alloc_cyclic(&uctx->xa, &key, uobj, limit, &uctx->uobj_nextkey,
+			    GFP_KERNEL) < 0) {
+		kfree(uobj);
+		return SIW_INVAL_UOBJ_KEY;
+	}
+	uobj->size = PAGE_ALIGN(size);
+	uobj->addr = vaddr;
+
+	return key;
+}
+
+static struct siw_uobj *siw_get_uobj(struct siw_ucontext *uctx,
+				     unsigned long off, u32 size)
+{
+	struct siw_uobj *uobj = xa_load(&uctx->xa, off);
+
+	if (uobj && uobj->size == size)
+		return uobj;
+
+	return NULL;
+}
+
+int siw_mmap(struct ib_ucontext *ctx, struct vm_area_struct *vma)
+{
+	struct siw_ucontext *uctx = to_siw_ctx(ctx);
+	struct siw_uobj *uobj;
+	unsigned long off = vma->vm_pgoff;
+	int size = vma->vm_end - vma->vm_start;
+	int rv = -EINVAL;
+
+	/*
+	 * Must be page aligned
+	 */
+	if (vma->vm_start & (PAGE_SIZE - 1)) {
+		pr_warn("siw: mmap not page aligned\n");
+		goto out;
+	}
+	uobj = siw_get_uobj(uctx, off, size);
+	if (!uobj) {
+		siw_dbg(&uctx->sdev->base_dev, "mmap lookup failed: %lu, %u\n",
+			off, size);
+		goto out;
+	}
+	rv = remap_vmalloc_range(vma, uobj->addr, 0);
+	if (rv)
+		pr_warn("remap_vmalloc_range failed: %lu, %u\n", off, size);
+out:
+	return rv;
+}
+
+int siw_alloc_ucontext(struct ib_ucontext *base_ctx, struct ib_udata *udata)
+{
+	struct siw_device *sdev = to_siw_dev(base_ctx->device);
+	struct siw_ucontext *ctx = to_siw_ctx(base_ctx);
+	struct siw_uresp_alloc_ctx uresp = {};
+	int rv;
+
+	if (atomic_inc_return(&sdev->num_ctx) > SIW_MAX_CONTEXT) {
+		rv = -ENOMEM;
+		goto err_out;
+	}
+	xa_init_flags(&ctx->xa, XA_FLAGS_ALLOC);
+	ctx->uobj_nextkey = 0;
+	ctx->sdev = sdev;
+
+	uresp.dev_id = sdev->vendor_part_id;
+
+	if (udata->outlen < sizeof(uresp)) {
+		rv = -EINVAL;
+		goto err_out;
+	}
+	rv = ib_copy_to_udata(udata, &uresp, sizeof(uresp));
+	if (rv)
+		goto err_out;
+
+	siw_dbg(base_ctx->device, "success. now %d context(s)\n",
+		atomic_read(&sdev->num_ctx));
+
+	return 0;
+
+err_out:
+	atomic_dec(&sdev->num_ctx);
+	siw_dbg(base_ctx->device, "failure %d. now %d context(s)\n", rv,
+		atomic_read(&sdev->num_ctx));
+
+	return rv;
+}
+
+void siw_dealloc_ucontext(struct ib_ucontext *base_ctx)
+{
+	struct siw_ucontext *uctx = to_siw_ctx(base_ctx);
+	void *entry;
+	unsigned long index;
+
+	/*
+	 * Make sure all user mmap objects are gone. Since QP, CQ
+	 * and SRQ destroy routines destroy related objects, nothing
+	 * should be found here.
+	 */
+	xa_for_each(&uctx->xa, index, entry) {
+		kfree(xa_erase(&uctx->xa, index));
+		pr_warn("siw: dropping orphaned uobj at %lu\n", index);
+	}
+	xa_destroy(&uctx->xa);
+	atomic_dec(&uctx->sdev->num_ctx);
+}
+
+int siw_query_device(struct ib_device *base_dev, struct ib_device_attr *attr,
+		     struct ib_udata *udata)
+{
+	struct siw_device *sdev = to_siw_dev(base_dev);
+
+	if (udata->inlen || udata->outlen)
+		return -EINVAL;
+
+	memset(attr, 0, sizeof(*attr));
+
+	/* Revisit atomic caps if RFC 7306 gets supported */
+	attr->atomic_cap = 0;
+	attr->device_cap_flags =
+		IB_DEVICE_MEM_MGT_EXTENSIONS | IB_DEVICE_ALLOW_USER_UNREG;
+	attr->max_cq = sdev->attrs.max_cq;
+	attr->max_cqe = sdev->attrs.max_cqe;
+	attr->max_fast_reg_page_list_len = SIW_MAX_SGE_PBL;
+	attr->max_fmr = sdev->attrs.max_fmr;
+	attr->max_mr = sdev->attrs.max_mr;
+	attr->max_mw = sdev->attrs.max_mw;
+	attr->max_mr_size = ~0ull;
+	attr->max_pd = sdev->attrs.max_pd;
+	attr->max_qp = sdev->attrs.max_qp;
+	attr->max_qp_init_rd_atom = sdev->attrs.max_ird;
+	attr->max_qp_rd_atom = sdev->attrs.max_ord;
+	attr->max_qp_wr = sdev->attrs.max_qp_wr;
+	attr->max_recv_sge = sdev->attrs.max_sge;
+	attr->max_res_rd_atom = sdev->attrs.max_qp * sdev->attrs.max_ird;
+	attr->max_send_sge = sdev->attrs.max_sge;
+	attr->max_sge_rd = sdev->attrs.max_sge_rd;
+	attr->max_srq = sdev->attrs.max_srq;
+	attr->max_srq_sge = sdev->attrs.max_srq_sge;
+	attr->max_srq_wr = sdev->attrs.max_srq_wr;
+	attr->page_size_cap = PAGE_SIZE;
+	attr->vendor_id = SIW_VENDOR_ID;
+	attr->vendor_part_id = sdev->vendor_part_id;
+
+	memcpy(&attr->sys_image_guid, sdev->netdev->dev_addr, 6);
+
+	return 0;
+}
+
+int siw_query_port(struct ib_device *base_dev, u8 port,
+		   struct ib_port_attr *attr)
+{
+	struct siw_device *sdev = to_siw_dev(base_dev);
+
+	memset(attr, 0, sizeof(*attr));
+
+	attr->active_mtu = attr->max_mtu;
+	attr->active_speed = 2;
+	attr->active_width = 2;
+	attr->gid_tbl_len = 1;
+	attr->max_msg_sz = -1;
+	attr->max_mtu = ib_mtu_int_to_enum(sdev->netdev->mtu);
+	attr->phys_state = sdev->state == IB_PORT_ACTIVE ? 5 : 3;
+	attr->pkey_tbl_len = 1;
+	attr->port_cap_flags = IB_PORT_CM_SUP | IB_PORT_DEVICE_MGMT_SUP;
+	attr->state = sdev->state;
+	/*
+	 * All zero
+	 *
+	 * attr->lid = 0;
+	 * attr->bad_pkey_cntr = 0;
+	 * attr->qkey_viol_cntr = 0;
+	 * attr->sm_lid = 0;
+	 * attr->lmc = 0;
+	 * attr->max_vl_num = 0;
+	 * attr->sm_sl = 0;
+	 * attr->subnet_timeout = 0;
+	 * attr->init_type_repy = 0;
+	 */
+	return 0;
+}
+
+int siw_get_port_immutable(struct ib_device *base_dev, u8 port,
+			   struct ib_port_immutable *port_immutable)
+{
+	struct ib_port_attr attr;
+	int rv = siw_query_port(base_dev, port, &attr);
+
+	if (rv)
+		return rv;
+
+	port_immutable->pkey_tbl_len = attr.pkey_tbl_len;
+	port_immutable->gid_tbl_len = attr.gid_tbl_len;
+	port_immutable->core_cap_flags = RDMA_CORE_PORT_IWARP;
+
+	return 0;
+}
+
+int siw_query_pkey(struct ib_device *base_dev, u8 port, u16 idx, u16 *pkey)
+{
+	/* Report the default pkey */
+	*pkey = 0xffff;
+	return 0;
+}
+
+int siw_query_gid(struct ib_device *base_dev, u8 port, int idx,
+		  union ib_gid *gid)
+{
+	struct siw_device *sdev = to_siw_dev(base_dev);
+
+	/* subnet_prefix == interface_id == 0; */
+	memset(gid, 0, sizeof(*gid));
+	memcpy(&gid->raw[0], sdev->netdev->dev_addr, 6);
+
+	return 0;
+}
+
+int siw_alloc_pd(struct ib_pd *pd, struct ib_udata *udata)
+{
+	struct siw_device *sdev = to_siw_dev(pd->device);
+
+	if (atomic_inc_return(&sdev->num_pd) > SIW_MAX_PD) {
+		atomic_dec(&sdev->num_pd);
+		return -ENOMEM;
+	}
+	siw_dbg_pd(pd, "now %d PD's(s)\n", atomic_read(&sdev->num_pd));
+
+	return 0;
+}
+
+void siw_dealloc_pd(struct ib_pd *pd, struct ib_udata *udata)
+{
+	struct siw_device *sdev = to_siw_dev(pd->device);
+
+	siw_dbg_pd(pd, "free PD\n");
+	atomic_dec(&sdev->num_pd);
+}
+
+void siw_qp_get_ref(struct ib_qp *base_qp)
+{
+	siw_qp_get(to_siw_qp(base_qp));
+}
+
+void siw_qp_put_ref(struct ib_qp *base_qp)
+{
+	siw_qp_put(to_siw_qp(base_qp));
+}
+
+/*
+ * siw_create_qp()
+ *
+ * Create QP of requested size on given device.
+ *
+ * @pd:		Protection Domain
+ * @attrs:	Initial QP attributes.
+ * @udata:	used to provide QP ID, SQ and RQ size back to user.
+ */
+
+struct ib_qp *siw_create_qp(struct ib_pd *pd,
+			    struct ib_qp_init_attr *attrs,
+			    struct ib_udata *udata)
+{
+	struct siw_qp *qp = NULL;
+	struct siw_base_qp *siw_base_qp = NULL;
+	struct ib_device *base_dev = pd->device;
+	struct siw_device *sdev = to_siw_dev(base_dev);
+	struct siw_ucontext *uctx =
+		rdma_udata_to_drv_context(udata, struct siw_ucontext,
+					  base_ucontext);
+	struct siw_cq *scq = NULL, *rcq = NULL;
+	unsigned long flags;
+	int num_sqe, num_rqe, rv = 0;
+
+	siw_dbg(base_dev, "create new QP\n");
+
+	if (atomic_inc_return(&sdev->num_qp) > SIW_MAX_QP) {
+		siw_dbg(base_dev, "too many QP's\n");
+		rv = -ENOMEM;
+		goto err_out;
+	}
+	if (attrs->qp_type != IB_QPT_RC) {
+		siw_dbg(base_dev, "only RC QP's supported\n");
+		rv = -EINVAL;
+		goto err_out;
+	}
+	if ((attrs->cap.max_send_wr > SIW_MAX_QP_WR) ||
+	    (attrs->cap.max_recv_wr > SIW_MAX_QP_WR) ||
+	    (attrs->cap.max_send_sge > SIW_MAX_SGE) ||
+	    (attrs->cap.max_recv_sge > SIW_MAX_SGE)) {
+		siw_dbg(base_dev, "QP size error\n");
+		rv = -EINVAL;
+		goto err_out;
+	}
+	if (attrs->cap.max_inline_data > SIW_MAX_INLINE) {
+		siw_dbg(base_dev, "max inline send: %d > %d\n",
+			attrs->cap.max_inline_data, (int)SIW_MAX_INLINE);
+		rv = -EINVAL;
+		goto err_out;
+	}
+	/*
+	 * NOTE: we allow for zero element SQ and RQ WQE's SGL's
+	 * but not for a QP unable to hold any WQE (SQ + RQ)
+	 */
+	if (attrs->cap.max_send_wr + attrs->cap.max_recv_wr == 0) {
+		siw_dbg(base_dev, "QP must have send or receive queue\n");
+		rv = -EINVAL;
+		goto err_out;
+	}
+	scq = to_siw_cq(attrs->send_cq);
+	rcq = to_siw_cq(attrs->recv_cq);
+
+	if (!scq || (!rcq && !attrs->srq)) {
+		siw_dbg(base_dev, "send CQ or receive CQ invalid\n");
+		rv = -EINVAL;
+		goto err_out;
+	}
+	siw_base_qp = kzalloc(sizeof(*siw_base_qp), GFP_KERNEL);
+	if (!siw_base_qp) {
+		rv = -ENOMEM;
+		goto err_out;
+	}
+	qp = kzalloc(sizeof(*qp), GFP_KERNEL);
+	if (!qp) {
+		rv = -ENOMEM;
+		goto err_out;
+	}
+	siw_base_qp->qp = qp;
+	qp->ib_qp = &siw_base_qp->base_qp;
+
+	init_rwsem(&qp->state_lock);
+	spin_lock_init(&qp->sq_lock);
+	spin_lock_init(&qp->rq_lock);
+	spin_lock_init(&qp->orq_lock);
+
+	qp->kernel_verbs = !udata;
+	qp->xa_sq_index = SIW_INVAL_UOBJ_KEY;
+	qp->xa_rq_index = SIW_INVAL_UOBJ_KEY;
+
+	rv = siw_qp_add(sdev, qp);
+	if (rv)
+		goto err_out;
+
+	/* All queue indices are derived from modulo operations
+	 * on a free running 'get' (consumer) and 'put' (producer)
+	 * unsigned counter. Having queue sizes at power of two
+	 * avoids handling counter wrap around.
+	 */
+	num_sqe = roundup_pow_of_two(attrs->cap.max_send_wr);
+	num_rqe = roundup_pow_of_two(attrs->cap.max_recv_wr);
+
+	if (qp->kernel_verbs)
+		qp->sendq = vzalloc(num_sqe * sizeof(struct siw_sqe));
+	else
+		qp->sendq = vmalloc_user(num_sqe * sizeof(struct siw_sqe));
+
+	if (qp->sendq == NULL) {
+		siw_dbg(base_dev, "SQ size %d alloc failed\n", num_sqe);
+		rv = -ENOMEM;
+		goto err_out_xa;
+	}
+	if (attrs->sq_sig_type != IB_SIGNAL_REQ_WR) {
+		if (attrs->sq_sig_type == IB_SIGNAL_ALL_WR)
+			qp->attrs.flags |= SIW_SIGNAL_ALL_WR;
+		else {
+			rv = -EINVAL;
+			goto err_out_xa;
+		}
+	}
+	qp->pd = pd;
+	qp->scq = scq;
+	qp->rcq = rcq;
+
+	if (attrs->srq) {
+		/*
+		 * SRQ support.
+		 * Verbs 6.3.7: ignore RQ size, if SRQ present
+		 * Verbs 6.3.5: do not check PD of SRQ against PD of QP
+		 */
+		qp->srq = to_siw_srq(attrs->srq);
+		qp->attrs.rq_size = 0;
+		siw_dbg(base_dev, "QP [%u]: [SRQ 0x%p] attached\n",
+			qp->qp_num, qp->srq);
+	} else if (num_rqe) {
+		if (qp->kernel_verbs)
+			qp->recvq = vzalloc(num_rqe * sizeof(struct siw_rqe));
+		else
+			qp->recvq =
+				vmalloc_user(num_rqe * sizeof(struct siw_rqe));
+
+		if (qp->recvq == NULL) {
+			siw_dbg(base_dev, "RQ size %d alloc failed\n", num_rqe);
+			rv = -ENOMEM;
+			goto err_out_xa;
+		}
+		qp->attrs.rq_size = num_rqe;
+	}
+	qp->attrs.sq_size = num_sqe;
+	qp->attrs.sq_max_sges = attrs->cap.max_send_sge;
+	qp->attrs.rq_max_sges = attrs->cap.max_recv_sge;
+
+	/* Make those two tunables fixed for now. */
+	qp->tx_ctx.gso_seg_limit = 1;
+	qp->tx_ctx.zcopy_tx = zcopy_tx;
+
+	qp->attrs.state = SIW_QP_STATE_IDLE;
+
+	if (udata) {
+		struct siw_uresp_create_qp uresp = {};
+
+		uresp.num_sqe = num_sqe;
+		uresp.num_rqe = num_rqe;
+		uresp.qp_id = qp_id(qp);
+
+		if (qp->sendq) {
+			qp->xa_sq_index =
+				siw_create_uobj(uctx, qp->sendq,
+					num_sqe * sizeof(struct siw_sqe));
+		}
+		if (qp->recvq) {
+			qp->xa_rq_index =
+				 siw_create_uobj(uctx, qp->recvq,
+					num_rqe * sizeof(struct siw_rqe));
+		}
+		if (qp->xa_sq_index == SIW_INVAL_UOBJ_KEY ||
+		    qp->xa_rq_index == SIW_INVAL_UOBJ_KEY) {
+			rv = -ENOMEM;
+			goto err_out_xa;
+		}
+		uresp.sq_key = qp->xa_sq_index << PAGE_SHIFT;
+		uresp.rq_key = qp->xa_rq_index << PAGE_SHIFT;
+
+		if (udata->outlen < sizeof(uresp)) {
+			rv = -EINVAL;
+			goto err_out_xa;
+		}
+		rv = ib_copy_to_udata(udata, &uresp, sizeof(uresp));
+		if (rv)
+			goto err_out_xa;
+	}
+	qp->tx_cpu = siw_get_tx_cpu(sdev);
+	if (qp->tx_cpu < 0) {
+		rv = -EINVAL;
+		goto err_out_xa;
+	}
+	INIT_LIST_HEAD(&qp->devq);
+	spin_lock_irqsave(&sdev->lock, flags);
+	list_add_tail(&qp->devq, &sdev->qp_list);
+	spin_unlock_irqrestore(&sdev->lock, flags);
+
+	return qp->ib_qp;
+
+err_out_xa:
+	xa_erase(&sdev->qp_xa, qp_id(qp));
+err_out:
+	kfree(siw_base_qp);
+
+	if (qp) {
+		if (qp->xa_sq_index != SIW_INVAL_UOBJ_KEY)
+			kfree(xa_erase(&uctx->xa, qp->xa_sq_index));
+		if (qp->xa_rq_index != SIW_INVAL_UOBJ_KEY)
+			kfree(xa_erase(&uctx->xa, qp->xa_rq_index));
+
+		vfree(qp->sendq);
+		vfree(qp->recvq);
+		kfree(qp);
+	}
+	atomic_dec(&sdev->num_qp);
+
+	return ERR_PTR(rv);
+}
+
+/*
+ * Minimum siw_query_qp() verb interface.
+ *
+ * @qp_attr_mask is not used but all available information is provided
+ */
+int siw_query_qp(struct ib_qp *base_qp, struct ib_qp_attr *qp_attr,
+		 int qp_attr_mask, struct ib_qp_init_attr *qp_init_attr)
+{
+	struct siw_qp *qp;
+	struct siw_device *sdev;
+
+	if (base_qp && qp_attr && qp_init_attr) {
+		qp = to_siw_qp(base_qp);
+		sdev = to_siw_dev(base_qp->device);
+	} else {
+		return -EINVAL;
+	}
+	qp_attr->cap.max_inline_data = SIW_MAX_INLINE;
+	qp_attr->cap.max_send_wr = qp->attrs.sq_size;
+	qp_attr->cap.max_send_sge = qp->attrs.sq_max_sges;
+	qp_attr->cap.max_recv_wr = qp->attrs.rq_size;
+	qp_attr->cap.max_recv_sge = qp->attrs.rq_max_sges;
+	qp_attr->path_mtu = ib_mtu_int_to_enum(sdev->netdev->mtu);
+	qp_attr->max_rd_atomic = qp->attrs.irq_size;
+	qp_attr->max_dest_rd_atomic = qp->attrs.orq_size;
+
+	qp_attr->qp_access_flags = IB_ACCESS_LOCAL_WRITE |
+				   IB_ACCESS_REMOTE_WRITE |
+				   IB_ACCESS_REMOTE_READ;
+
+	qp_init_attr->qp_type = base_qp->qp_type;
+	qp_init_attr->send_cq = base_qp->send_cq;
+	qp_init_attr->recv_cq = base_qp->recv_cq;
+	qp_init_attr->srq = base_qp->srq;
+
+	qp_init_attr->cap = qp_attr->cap;
+
+	return 0;
+}
+
+int siw_verbs_modify_qp(struct ib_qp *base_qp, struct ib_qp_attr *attr,
+			int attr_mask, struct ib_udata *udata)
+{
+	struct siw_qp_attrs new_attrs;
+	enum siw_qp_attr_mask siw_attr_mask = 0;
+	struct siw_qp *qp = to_siw_qp(base_qp);
+	int rv = 0;
+
+	if (!attr_mask)
+		return 0;
+
+	memset(&new_attrs, 0, sizeof(new_attrs));
+
+	if (attr_mask & IB_QP_ACCESS_FLAGS) {
+		siw_attr_mask = SIW_QP_ATTR_ACCESS_FLAGS;
+
+		if (attr->qp_access_flags & IB_ACCESS_REMOTE_READ)
+			new_attrs.flags |= SIW_RDMA_READ_ENABLED;
+		if (attr->qp_access_flags & IB_ACCESS_REMOTE_WRITE)
+			new_attrs.flags |= SIW_RDMA_WRITE_ENABLED;
+		if (attr->qp_access_flags & IB_ACCESS_MW_BIND)
+			new_attrs.flags |= SIW_RDMA_BIND_ENABLED;
+	}
+	if (attr_mask & IB_QP_STATE) {
+		siw_dbg_qp(qp, "desired IB QP state: %s\n",
+			   ib_qp_state_to_string[attr->qp_state]);
+
+		new_attrs.state = ib_qp_state_to_siw_qp_state[attr->qp_state];
+
+		if (new_attrs.state > SIW_QP_STATE_RTS)
+			qp->tx_ctx.tx_suspend = 1;
+
+		siw_attr_mask |= SIW_QP_ATTR_STATE;
+	}
+	if (!siw_attr_mask)
+		goto out;
+
+	down_write(&qp->state_lock);
+
+	rv = siw_qp_modify(qp, &new_attrs, siw_attr_mask);
+
+	up_write(&qp->state_lock);
+out:
+	return rv;
+}
+
+int siw_destroy_qp(struct ib_qp *base_qp, struct ib_udata *udata)
+{
+	struct siw_qp *qp = to_siw_qp(base_qp);
+	struct siw_base_qp *siw_base_qp = to_siw_base_qp(base_qp);
+	struct siw_ucontext *uctx =
+		rdma_udata_to_drv_context(udata, struct siw_ucontext,
+					  base_ucontext);
+	struct siw_qp_attrs qp_attrs;
+
+	siw_dbg_qp(qp, "state %d, cep 0x%p\n", qp->attrs.state, qp->cep);
+
+	/*
+	 * Mark QP as in process of destruction to prevent from
+	 * any async callbacks to RDMA core
+	 */
+	qp->attrs.flags |= SIW_QP_IN_DESTROY;
+	qp->rx_stream.rx_suspend = 1;
+
+	if (uctx && qp->xa_sq_index != SIW_INVAL_UOBJ_KEY)
+		kfree(xa_erase(&uctx->xa, qp->xa_sq_index));
+	if (uctx && qp->xa_rq_index != SIW_INVAL_UOBJ_KEY)
+		kfree(xa_erase(&uctx->xa, qp->xa_rq_index));
+
+	down_write(&qp->state_lock);
+
+	qp_attrs.state = SIW_QP_STATE_ERROR;
+	siw_qp_modify(qp, &qp_attrs, SIW_QP_ATTR_STATE);
+
+	if (qp->cep) {
+		siw_cep_put(qp->cep);
+		qp->cep = NULL;
+	}
+	up_write(&qp->state_lock);
+
+	kfree(qp->tx_ctx.mpa_crc_hd);
+	kfree(qp->rx_stream.mpa_crc_hd);
+
+	qp->scq = qp->rcq = NULL;
+
+	siw_qp_put(qp);
+	kfree(siw_base_qp);
+
+	return 0;
+}
+
+/*
+ * siw_copy_inline_sgl()
+ *
+ * Prepare sgl of inlined data for sending. For userland callers
+ * function checks if given buffer addresses and len's are within
+ * process context bounds.
+ * Data from all provided sge's are copied together into the wqe,
+ * referenced by a single sge.
+ */
+static int siw_copy_inline_sgl(const struct ib_send_wr *core_wr,
+			       struct siw_sqe *sqe)
+{
+	struct ib_sge *core_sge = core_wr->sg_list;
+	void *kbuf = &sqe->sge[1];
+	int num_sge = core_wr->num_sge, bytes = 0;
+
+	sqe->sge[0].laddr = (u64)kbuf;
+	sqe->sge[0].lkey = 0;
+
+	while (num_sge--) {
+		if (!core_sge->length) {
+			core_sge++;
+			continue;
+		}
+		bytes += core_sge->length;
+		if (bytes > SIW_MAX_INLINE) {
+			bytes = -EINVAL;
+			break;
+		}
+		memcpy(kbuf, (void *)(uintptr_t)core_sge->addr,
+		       core_sge->length);
+
+		kbuf += core_sge->length;
+		core_sge++;
+	}
+	sqe->sge[0].length = bytes > 0 ? bytes : 0;
+	sqe->num_sge = bytes > 0 ? 1 : 0;
+
+	return bytes;
+}
+
+/*
+ * siw_post_send()
+ *
+ * Post a list of S-WR's to a SQ.
+ *
+ * @base_qp:	Base QP contained in siw QP
+ * @wr:		Null terminated list of user WR's
+ * @bad_wr:	Points to failing WR in case of synchronous failure.
+ */
+int siw_post_send(struct ib_qp *base_qp, const struct ib_send_wr *wr,
+		  const struct ib_send_wr **bad_wr)
+{
+	struct siw_qp *qp = to_siw_qp(base_qp);
+	struct siw_wqe *wqe = tx_wqe(qp);
+
+	unsigned long flags;
+	int rv = 0;
+
+	/*
+	 * Try to acquire QP state lock. Must be non-blocking
+	 * to accommodate kernel clients needs.
+	 */
+	if (!down_read_trylock(&qp->state_lock)) {
+		*bad_wr = wr;
+		siw_dbg_qp(qp, "QP locked, state %d\n", qp->attrs.state);
+		return -ENOTCONN;
+	}
+	if (unlikely(qp->attrs.state != SIW_QP_STATE_RTS)) {
+		up_read(&qp->state_lock);
+		*bad_wr = wr;
+		siw_dbg_qp(qp, "QP out of state %d\n", qp->attrs.state);
+		return -ENOTCONN;
+	}
+	if (wr && !qp->kernel_verbs) {
+		siw_dbg_qp(qp, "wr must be empty for user mapped sq\n");
+		up_read(&qp->state_lock);
+		*bad_wr = wr;
+		return -EINVAL;
+	}
+	spin_lock_irqsave(&qp->sq_lock, flags);
+
+	while (wr) {
+		u32 idx = qp->sq_put % qp->attrs.sq_size;
+		struct siw_sqe *sqe = &qp->sendq[idx];
+
+		if (sqe->flags) {
+			siw_dbg_qp(qp, "sq full\n");
+			rv = -ENOMEM;
+			break;
+		}
+		if (wr->num_sge > qp->attrs.sq_max_sges) {
+			siw_dbg_qp(qp, "too many sge's: %d\n", wr->num_sge);
+			rv = -EINVAL;
+			break;
+		}
+		sqe->id = wr->wr_id;
+
+		if ((wr->send_flags & IB_SEND_SIGNALED) ||
+		    (qp->attrs.flags & SIW_SIGNAL_ALL_WR))
+			sqe->flags |= SIW_WQE_SIGNALLED;
+
+		if (wr->send_flags & IB_SEND_FENCE)
+			sqe->flags |= SIW_WQE_READ_FENCE;
+
+		switch (wr->opcode) {
+		case IB_WR_SEND:
+		case IB_WR_SEND_WITH_INV:
+			if (wr->send_flags & IB_SEND_SOLICITED)
+				sqe->flags |= SIW_WQE_SOLICITED;
+
+			if (!(wr->send_flags & IB_SEND_INLINE)) {
+				siw_copy_sgl(wr->sg_list, sqe->sge,
+					     wr->num_sge);
+				sqe->num_sge = wr->num_sge;
+			} else {
+				rv = siw_copy_inline_sgl(wr, sqe);
+				if (rv <= 0) {
+					rv = -EINVAL;
+					break;
+				}
+				sqe->flags |= SIW_WQE_INLINE;
+				sqe->num_sge = 1;
+			}
+			if (wr->opcode == IB_WR_SEND)
+				sqe->opcode = SIW_OP_SEND;
+			else {
+				sqe->opcode = SIW_OP_SEND_REMOTE_INV;
+				sqe->rkey = wr->ex.invalidate_rkey;
+			}
+			break;
+
+		case IB_WR_RDMA_READ_WITH_INV:
+		case IB_WR_RDMA_READ:
+			/*
+			 * iWarp restricts RREAD sink to SGL containing
+			 * 1 SGE only. we could relax to SGL with multiple
+			 * elements referring the SAME ltag or even sending
+			 * a private per-rreq tag referring to a checked
+			 * local sgl with MULTIPLE ltag's.
+			 */
+			if (unlikely(wr->num_sge != 1)) {
+				rv = -EINVAL;
+				break;
+			}
+			siw_copy_sgl(wr->sg_list, &sqe->sge[0], 1);
+			/*
+			 * NOTE: zero length RREAD is allowed!
+			 */
+			sqe->raddr = rdma_wr(wr)->remote_addr;
+			sqe->rkey = rdma_wr(wr)->rkey;
+			sqe->num_sge = 1;
+
+			if (wr->opcode == IB_WR_RDMA_READ)
+				sqe->opcode = SIW_OP_READ;
+			else
+				sqe->opcode = SIW_OP_READ_LOCAL_INV;
+			break;
+
+		case IB_WR_RDMA_WRITE:
+			if (!(wr->send_flags & IB_SEND_INLINE)) {
+				siw_copy_sgl(wr->sg_list, &sqe->sge[0],
+					     wr->num_sge);
+				sqe->num_sge = wr->num_sge;
+			} else {
+				rv = siw_copy_inline_sgl(wr, sqe);
+				if (unlikely(rv < 0)) {
+					rv = -EINVAL;
+					break;
+				}
+				sqe->flags |= SIW_WQE_INLINE;
+				sqe->num_sge = 1;
+			}
+			sqe->raddr = rdma_wr(wr)->remote_addr;
+			sqe->rkey = rdma_wr(wr)->rkey;
+			sqe->opcode = SIW_OP_WRITE;
+			break;
+
+		case IB_WR_REG_MR:
+			sqe->base_mr = (uint64_t)reg_wr(wr)->mr;
+			sqe->rkey = reg_wr(wr)->key;
+			sqe->access = reg_wr(wr)->access & IWARP_ACCESS_MASK;
+			sqe->opcode = SIW_OP_REG_MR;
+			break;
+
+		case IB_WR_LOCAL_INV:
+			sqe->rkey = wr->ex.invalidate_rkey;
+			sqe->opcode = SIW_OP_INVAL_STAG;
+			break;
+
+		default:
+			siw_dbg_qp(qp, "ib wr type %d unsupported\n",
+				   wr->opcode);
+			rv = -EINVAL;
+			break;
+		}
+		siw_dbg_qp(qp, "opcode %d, flags 0x%x, wr_id 0x%p\n",
+			   sqe->opcode, sqe->flags, (void *)sqe->id);
+
+		if (unlikely(rv < 0))
+			break;
+
+		/* make SQE only valid after completely written */
+		smp_wmb();
+		sqe->flags |= SIW_WQE_VALID;
+
+		qp->sq_put++;
+		wr = wr->next;
+	}
+
+	/*
+	 * Send directly if SQ processing is not in progress.
+	 * Eventual immediate errors (rv < 0) do not affect the involved
+	 * RI resources (Verbs, 8.3.1) and thus do not prevent from SQ
+	 * processing, if new work is already pending. But rv must be passed
+	 * to caller.
+	 */
+	if (wqe->wr_status != SIW_WR_IDLE) {
+		spin_unlock_irqrestore(&qp->sq_lock, flags);
+		goto skip_direct_sending;
+	}
+	rv = siw_activate_tx(qp);
+	spin_unlock_irqrestore(&qp->sq_lock, flags);
+
+	if (rv <= 0)
+		goto skip_direct_sending;
+
+	if (qp->kernel_verbs) {
+		rv = siw_sq_start(qp);
+	} else {
+		qp->tx_ctx.in_syscall = 1;
+
+		if (siw_qp_sq_process(qp) != 0 && !(qp->tx_ctx.tx_suspend))
+			siw_qp_cm_drop(qp, 0);
+
+		qp->tx_ctx.in_syscall = 0;
+	}
+skip_direct_sending:
+
+	up_read(&qp->state_lock);
+
+	if (rv >= 0)
+		return 0;
+	/*
+	 * Immediate error
+	 */
+	siw_dbg_qp(qp, "error %d\n", rv);
+
+	*bad_wr = wr;
+	return rv;
+}
+
+/*
+ * siw_post_receive()
+ *
+ * Post a list of R-WR's to a RQ.
+ *
+ * @base_qp:	Base QP contained in siw QP
+ * @wr:		Null terminated list of user WR's
+ * @bad_wr:	Points to failing WR in case of synchronous failure.
+ */
+int siw_post_receive(struct ib_qp *base_qp, const struct ib_recv_wr *wr,
+		     const struct ib_recv_wr **bad_wr)
+{
+	struct siw_qp *qp = to_siw_qp(base_qp);
+	unsigned long flags;
+	int rv = 0;
+
+	if (qp->srq) {
+		*bad_wr = wr;
+		return -EOPNOTSUPP; /* what else from errno.h? */
+	}
+	/*
+	 * Try to acquire QP state lock. Must be non-blocking
+	 * to accommodate kernel clients needs.
+	 */
+	if (!down_read_trylock(&qp->state_lock)) {
+		*bad_wr = wr;
+		return -ENOTCONN;
+	}
+	if (!qp->kernel_verbs) {
+		siw_dbg_qp(qp, "no kernel post_recv for user mapped sq\n");
+		up_read(&qp->state_lock);
+		*bad_wr = wr;
+		return -EINVAL;
+	}
+	if (qp->attrs.state > SIW_QP_STATE_RTS) {
+		up_read(&qp->state_lock);
+		*bad_wr = wr;
+		return -EINVAL;
+	}
+	/*
+	 * Serialize potentially multiple producers.
+	 * Not needed for single threaded consumer side.
+	 */
+	spin_lock_irqsave(&qp->rq_lock, flags);
+
+	while (wr) {
+		u32 idx = qp->rq_put % qp->attrs.rq_size;
+		struct siw_rqe *rqe = &qp->recvq[idx];
+
+		if (rqe->flags) {
+			siw_dbg_qp(qp, "RQ full\n");
+			rv = -ENOMEM;
+			break;
+		}
+		if (wr->num_sge > qp->attrs.rq_max_sges) {
+			siw_dbg_qp(qp, "too many sge's: %d\n", wr->num_sge);
+			rv = -EINVAL;
+			break;
+		}
+		rqe->id = wr->wr_id;
+		rqe->num_sge = wr->num_sge;
+		siw_copy_sgl(wr->sg_list, rqe->sge, wr->num_sge);
+
+		/* make sure RQE is completely written before valid */
+		smp_wmb();
+
+		rqe->flags = SIW_WQE_VALID;
+
+		qp->rq_put++;
+		wr = wr->next;
+	}
+	spin_unlock_irqrestore(&qp->rq_lock, flags);
+
+	up_read(&qp->state_lock);
+
+	if (rv < 0) {
+		siw_dbg_qp(qp, "error %d\n", rv);
+		*bad_wr = wr;
+	}
+	return rv > 0 ? 0 : rv;
+}
+
+void siw_destroy_cq(struct ib_cq *base_cq, struct ib_udata *udata)
+{
+	struct siw_cq *cq = to_siw_cq(base_cq);
+	struct siw_device *sdev = to_siw_dev(base_cq->device);
+	struct siw_ucontext *ctx =
+		rdma_udata_to_drv_context(udata, struct siw_ucontext,
+					  base_ucontext);
+
+	siw_dbg_cq(cq, "free CQ resources\n");
+
+	siw_cq_flush(cq);
+
+	if (ctx && cq->xa_cq_index != SIW_INVAL_UOBJ_KEY)
+		kfree(xa_erase(&ctx->xa, cq->xa_cq_index));
+
+	atomic_dec(&sdev->num_cq);
+
+	vfree(cq->queue);
+}
+
+/*
+ * siw_create_cq()
+ *
+ * Populate CQ of requested size
+ *
+ * @base_cq: CQ as allocated by RDMA midlayer
+ * @attr: Initial CQ attributes
+ * @udata: relates to user context
+ */
+
+int siw_create_cq(struct ib_cq *base_cq, const struct ib_cq_init_attr *attr,
+		  struct ib_udata *udata)
+{
+	struct siw_device *sdev = to_siw_dev(base_cq->device);
+	struct siw_cq *cq = to_siw_cq(base_cq);
+	int rv, size = attr->cqe;
+
+	if (atomic_inc_return(&sdev->num_cq) > SIW_MAX_CQ) {
+		siw_dbg(base_cq->device, "too many CQ's\n");
+		rv = -ENOMEM;
+		goto err_out;
+	}
+	if (size < 1 || size > sdev->attrs.max_cqe) {
+		siw_dbg(base_cq->device, "CQ size error: %d\n", size);
+		rv = -EINVAL;
+		goto err_out;
+	}
+	size = roundup_pow_of_two(size);
+	cq->base_cq.cqe = size;
+	cq->num_cqe = size;
+	cq->xa_cq_index = SIW_INVAL_UOBJ_KEY;
+
+	if (!udata) {
+		cq->kernel_verbs = 1;
+		cq->queue = vzalloc(size * sizeof(struct siw_cqe) +
+				    sizeof(struct siw_cq_ctrl));
+	} else {
+		cq->queue = vmalloc_user(size * sizeof(struct siw_cqe) +
+					 sizeof(struct siw_cq_ctrl));
+	}
+	if (cq->queue == NULL) {
+		rv = -ENOMEM;
+		goto err_out;
+	}
+	get_random_bytes(&cq->id, 4);
+	siw_dbg(base_cq->device, "new CQ [%u]\n", cq->id);
+
+	spin_lock_init(&cq->lock);
+
+	cq->notify = &((struct siw_cq_ctrl *)&cq->queue[size])->notify;
+
+	if (udata) {
+		struct siw_uresp_create_cq uresp = {};
+		struct siw_ucontext *ctx =
+			rdma_udata_to_drv_context(udata, struct siw_ucontext,
+						  base_ucontext);
+
+		cq->xa_cq_index =
+			siw_create_uobj(ctx, cq->queue,
+					size * sizeof(struct siw_cqe) +
+						sizeof(struct siw_cq_ctrl));
+		if (cq->xa_cq_index == SIW_INVAL_UOBJ_KEY) {
+			rv = -ENOMEM;
+			goto err_out;
+		}
+		uresp.cq_key = cq->xa_cq_index << PAGE_SHIFT;
+		uresp.cq_id = cq->id;
+		uresp.num_cqe = size;
+
+		if (udata->outlen < sizeof(uresp)) {
+			rv = -EINVAL;
+			goto err_out;
+		}
+		rv = ib_copy_to_udata(udata, &uresp, sizeof(uresp));
+		if (rv)
+			goto err_out;
+	}
+	return 0;
+
+err_out:
+	siw_dbg(base_cq->device, "CQ creation failed: %d", rv);
+
+	if (cq && cq->queue) {
+		struct siw_ucontext *ctx =
+			rdma_udata_to_drv_context(udata, struct siw_ucontext,
+						  base_ucontext);
+		if (cq->xa_cq_index != SIW_INVAL_UOBJ_KEY)
+			kfree(xa_erase(&ctx->xa, cq->xa_cq_index));
+		vfree(cq->queue);
+	}
+	atomic_dec(&sdev->num_cq);
+
+	return rv;
+}
+
+/*
+ * siw_poll_cq()
+ *
+ * Reap CQ entries if available and copy work completion status into
+ * array of WC's provided by caller. Returns number of reaped CQE's.
+ *
+ * @base_cq:	Base CQ contained in siw CQ.
+ * @num_cqe:	Maximum number of CQE's to reap.
+ * @wc:		Array of work completions to be filled by siw.
+ */
+int siw_poll_cq(struct ib_cq *base_cq, int num_cqe, struct ib_wc *wc)
+{
+	struct siw_cq *cq = to_siw_cq(base_cq);
+	int i;
+
+	for (i = 0; i < num_cqe; i++) {
+		if (!siw_reap_cqe(cq, wc))
+			break;
+		wc++;
+	}
+	return i;
+}
+
+/*
+ * siw_req_notify_cq()
+ *
+ * Request notification for new CQE's added to that CQ.
+ * Defined flags:
+ * o SIW_CQ_NOTIFY_SOLICITED lets siw trigger a notification
+ *   event if a WQE with notification flag set enters the CQ
+ * o SIW_CQ_NOTIFY_NEXT_COMP lets siw trigger a notification
+ *   event if a WQE enters the CQ.
+ * o IB_CQ_REPORT_MISSED_EVENTS: return value will provide the
+ *   number of not reaped CQE's regardless of its notification
+ *   type and current or new CQ notification settings.
+ *
+ * @base_cq:	Base CQ contained in siw CQ.
+ * @flags:	Requested notification flags.
+ */
+int siw_req_notify_cq(struct ib_cq *base_cq, enum ib_cq_notify_flags flags)
+{
+	struct siw_cq *cq = to_siw_cq(base_cq);
+
+	siw_dbg_cq(cq, "flags: 0x%02x\n", flags);
+
+	if ((flags & IB_CQ_SOLICITED_MASK) == IB_CQ_SOLICITED)
+		/* CQ event for next solicited completion */
+		smp_store_mb(*cq->notify, SIW_NOTIFY_SOLICITED);
+	else
+		/* CQ event for any signalled completion */
+		smp_store_mb(*cq->notify, SIW_NOTIFY_ALL);
+
+	if (flags & IB_CQ_REPORT_MISSED_EVENTS)
+		return cq->cq_put - cq->cq_get;
+
+	return 0;
+}
+
+/*
+ * siw_dereg_mr()
+ *
+ * Release Memory Region.
+ *
+ * @base_mr: Base MR contained in siw MR.
+ * @udata: points to user context, unused.
+ */
+int siw_dereg_mr(struct ib_mr *base_mr, struct ib_udata *udata)
+{
+	struct siw_mr *mr = to_siw_mr(base_mr);
+	struct siw_device *sdev = to_siw_dev(base_mr->device);
+
+	siw_dbg_mem(mr->mem, "deregister MR\n");
+
+	atomic_dec(&sdev->num_mr);
+
+	siw_mr_drop_mem(mr);
+	kfree_rcu(mr, rcu);
+
+	return 0;
+}
+
+/*
+ * siw_reg_user_mr()
+ *
+ * Register Memory Region.
+ *
+ * @pd:		Protection Domain
+ * @start:	starting address of MR (virtual address)
+ * @len:	len of MR
+ * @rnic_va:	not used by siw
+ * @rights:	MR access rights
+ * @udata:	user buffer to communicate STag and Key.
+ */
+struct ib_mr *siw_reg_user_mr(struct ib_pd *pd, u64 start, u64 len,
+			      u64 rnic_va, int rights, struct ib_udata *udata)
+{
+	struct siw_mr *mr = NULL;
+	struct siw_umem *umem = NULL;
+	struct siw_ureq_reg_mr ureq;
+	struct siw_device *sdev = to_siw_dev(pd->device);
+
+	unsigned long mem_limit = rlimit(RLIMIT_MEMLOCK);
+	int rv;
+
+	siw_dbg_pd(pd, "start: 0x%016llx, va: 0x%016llx, len: %llu\n",
+		   (unsigned long long)start, (unsigned long long)rnic_va,
+		   (unsigned long long)len);
+
+	if (atomic_inc_return(&sdev->num_mr) > SIW_MAX_MR) {
+		siw_dbg_pd(pd, "too many mr's\n");
+		rv = -ENOMEM;
+		goto err_out;
+	}
+	if (!len) {
+		rv = -EINVAL;
+		goto err_out;
+	}
+	if (mem_limit != RLIM_INFINITY) {
+		unsigned long num_pages =
+			(PAGE_ALIGN(len + (start & ~PAGE_MASK))) >> PAGE_SHIFT;
+		mem_limit >>= PAGE_SHIFT;
+
+		if (num_pages > mem_limit - current->mm->locked_vm) {
+			siw_dbg_pd(pd, "pages req %lu, max %lu, lock %lu\n",
+				   num_pages, mem_limit,
+				   current->mm->locked_vm);
+			rv = -ENOMEM;
+			goto err_out;
+		}
+	}
+	umem = siw_umem_get(start, len, ib_access_writable(rights));
+	if (IS_ERR(umem)) {
+		rv = PTR_ERR(umem);
+		siw_dbg_pd(pd, "getting user memory failed: %d\n", rv);
+		umem = NULL;
+		goto err_out;
+	}
+	mr = kzalloc(sizeof(*mr), GFP_KERNEL);
+	if (!mr) {
+		rv = -ENOMEM;
+		goto err_out;
+	}
+	rv = siw_mr_add_mem(mr, pd, umem, start, len, rights);
+	if (rv)
+		goto err_out;
+
+	if (udata) {
+		struct siw_uresp_reg_mr uresp = {};
+		struct siw_mem *mem = mr->mem;
+
+		if (udata->inlen < sizeof(ureq)) {
+			rv = -EINVAL;
+			goto err_out;
+		}
+		rv = ib_copy_from_udata(&ureq, udata, sizeof(ureq));
+		if (rv)
+			goto err_out;
+
+		mr->base_mr.lkey |= ureq.stag_key;
+		mr->base_mr.rkey |= ureq.stag_key;
+		mem->stag |= ureq.stag_key;
+		uresp.stag = mem->stag;
+
+		if (udata->outlen < sizeof(uresp)) {
+			rv = -EINVAL;
+			goto err_out;
+		}
+		rv = ib_copy_to_udata(udata, &uresp, sizeof(uresp));
+		if (rv)
+			goto err_out;
+	}
+	mr->mem->stag_valid = 1;
+
+	return &mr->base_mr;
+
+err_out:
+	atomic_dec(&sdev->num_mr);
+	if (mr) {
+		if (mr->mem)
+			siw_mr_drop_mem(mr);
+		kfree_rcu(mr, rcu);
+	} else {
+		if (umem)
+			siw_umem_release(umem, false);
+	}
+	return ERR_PTR(rv);
+}
+
+struct ib_mr *siw_alloc_mr(struct ib_pd *pd, enum ib_mr_type mr_type,
+			   u32 max_sge, struct ib_udata *udata)
+{
+	struct siw_device *sdev = to_siw_dev(pd->device);
+	struct siw_mr *mr = NULL;
+	struct siw_pbl *pbl = NULL;
+	int rv;
+
+	if (atomic_inc_return(&sdev->num_mr) > SIW_MAX_MR) {
+		siw_dbg_pd(pd, "too many mr's\n");
+		rv = -ENOMEM;
+		goto err_out;
+	}
+	if (mr_type != IB_MR_TYPE_MEM_REG) {
+		siw_dbg_pd(pd, "mr type %d unsupported\n", mr_type);
+		rv = -EOPNOTSUPP;
+		goto err_out;
+	}
+	if (max_sge > SIW_MAX_SGE_PBL) {
+		siw_dbg_pd(pd, "too many sge's: %d\n", max_sge);
+		rv = -ENOMEM;
+		goto err_out;
+	}
+	pbl = siw_pbl_alloc(max_sge);
+	if (IS_ERR(pbl)) {
+		rv = PTR_ERR(pbl);
+		siw_dbg_pd(pd, "pbl allocation failed: %d\n", rv);
+		pbl = NULL;
+		goto err_out;
+	}
+	mr = kzalloc(sizeof(*mr), GFP_KERNEL);
+	if (!mr) {
+		rv = -ENOMEM;
+		goto err_out;
+	}
+	rv = siw_mr_add_mem(mr, pd, pbl, 0, max_sge * PAGE_SIZE, 0);
+	if (rv)
+		goto err_out;
+
+	mr->mem->is_pbl = 1;
+
+	siw_dbg_pd(pd, "[MEM %u]: success\n", mr->mem->stag);
+
+	return &mr->base_mr;
+
+err_out:
+	atomic_dec(&sdev->num_mr);
+
+	if (!mr) {
+		kfree(pbl);
+	} else {
+		if (mr->mem)
+			siw_mr_drop_mem(mr);
+		kfree_rcu(mr, rcu);
+	}
+	siw_dbg_pd(pd, "failed: %d\n", rv);
+
+	return ERR_PTR(rv);
+}
+
+/* Just used to count number of pages being mapped */
+static int siw_set_pbl_page(struct ib_mr *base_mr, u64 buf_addr)
+{
+	return 0;
+}
+
+int siw_map_mr_sg(struct ib_mr *base_mr, struct scatterlist *sl, int num_sle,
+		  unsigned int *sg_off)
+{
+	struct scatterlist *slp;
+	struct siw_mr *mr = to_siw_mr(base_mr);
+	struct siw_mem *mem = mr->mem;
+	struct siw_pbl *pbl = mem->pbl;
+	struct siw_pble *pble;
+	u64 pbl_size;
+	int i, rv;
+
+	if (!pbl) {
+		siw_dbg_mem(mem, "no PBL allocated\n");
+		return -EINVAL;
+	}
+	pble = pbl->pbe;
+
+	if (pbl->max_buf < num_sle) {
+		siw_dbg_mem(mem, "too many SGE's: %d > %d\n",
+			    mem->pbl->max_buf, num_sle);
+		return -ENOMEM;
+	}
+	for_each_sg(sl, slp, num_sle, i) {
+		if (sg_dma_len(slp) == 0) {
+			siw_dbg_mem(mem, "empty SGE\n");
+			return -EINVAL;
+		}
+		if (i == 0) {
+			pble->addr = sg_dma_address(slp);
+			pble->size = sg_dma_len(slp);
+			pble->pbl_off = 0;
+			pbl_size = pble->size;
+			pbl->num_buf = 1;
+		} else {
+			/* Merge PBL entries if adjacent */
+			if (pble->addr + pble->size == sg_dma_address(slp)) {
+				pble->size += sg_dma_len(slp);
+			} else {
+				pble++;
+				pbl->num_buf++;
+				pble->addr = sg_dma_address(slp);
+				pble->size = sg_dma_len(slp);
+				pble->pbl_off = pbl_size;
+			}
+			pbl_size += sg_dma_len(slp);
+		}
+		siw_dbg_mem(mem,
+			"sge[%d], size %llu, addr 0x%016llx, total %llu\n",
+			i, pble->size, pble->addr, pbl_size);
+	}
+	rv = ib_sg_to_pages(base_mr, sl, num_sle, sg_off, siw_set_pbl_page);
+	if (rv > 0) {
+		mem->len = base_mr->length;
+		mem->va = base_mr->iova;
+		siw_dbg_mem(mem,
+			"%llu bytes, start 0x%016llx, %u SLE to %u entries\n",
+			mem->len, mem->va, num_sle, pbl->num_buf);
+	}
+	return rv;
+}
+
+/*
+ * siw_get_dma_mr()
+ *
+ * Create a (empty) DMA memory region, where no umem is attached.
+ */
+struct ib_mr *siw_get_dma_mr(struct ib_pd *pd, int rights)
+{
+	struct siw_device *sdev = to_siw_dev(pd->device);
+	struct siw_mr *mr = NULL;
+	int rv;
+
+	if (atomic_inc_return(&sdev->num_mr) > SIW_MAX_MR) {
+		siw_dbg_pd(pd, "too many mr's\n");
+		rv = -ENOMEM;
+		goto err_out;
+	}
+	mr = kzalloc(sizeof(*mr), GFP_KERNEL);
+	if (!mr) {
+		rv = -ENOMEM;
+		goto err_out;
+	}
+	rv = siw_mr_add_mem(mr, pd, NULL, 0, ULONG_MAX, rights);
+	if (rv)
+		goto err_out;
+
+	mr->mem->stag_valid = 1;
+
+	siw_dbg_pd(pd, "[MEM %u]: success\n", mr->mem->stag);
+
+	return &mr->base_mr;
+
+err_out:
+	if (rv)
+		kfree(mr);
+
+	atomic_dec(&sdev->num_mr);
+
+	return ERR_PTR(rv);
+}
+
+/*
+ * siw_create_srq()
+ *
+ * Create Shared Receive Queue of attributes @init_attrs
+ * within protection domain given by @pd.
+ *
+ * @base_srq:	Base SRQ contained in siw SRQ.
+ * @init_attrs:	SRQ init attributes.
+ * @udata:	points to user context
+ */
+int siw_create_srq(struct ib_srq *base_srq,
+		   struct ib_srq_init_attr *init_attrs, struct ib_udata *udata)
+{
+	struct siw_srq *srq = to_siw_srq(base_srq);
+	struct ib_srq_attr *attrs = &init_attrs->attr;
+	struct siw_device *sdev = to_siw_dev(base_srq->device);
+	struct siw_ucontext *ctx =
+		rdma_udata_to_drv_context(udata, struct siw_ucontext,
+					  base_ucontext);
+	int rv;
+
+	if (atomic_inc_return(&sdev->num_srq) > SIW_MAX_SRQ) {
+		siw_dbg_pd(base_srq->pd, "too many SRQ's\n");
+		rv = -ENOMEM;
+		goto err_out;
+	}
+	if (attrs->max_wr == 0 || attrs->max_wr > SIW_MAX_SRQ_WR ||
+	    attrs->max_sge > SIW_MAX_SGE || attrs->srq_limit > attrs->max_wr) {
+		rv = -EINVAL;
+		goto err_out;
+	}
+	srq->max_sge = attrs->max_sge;
+	srq->num_rqe = roundup_pow_of_two(attrs->max_wr);
+	srq->xa_srq_index = SIW_INVAL_UOBJ_KEY;
+	srq->limit = attrs->srq_limit;
+	if (srq->limit)
+		srq->armed = 1;
+
+	srq->kernel_verbs = !udata;
+
+	if (udata)
+		srq->recvq =
+			vmalloc_user(srq->num_rqe * sizeof(struct siw_rqe));
+	else
+		srq->recvq = vzalloc(srq->num_rqe * sizeof(struct siw_rqe));
+
+	if (srq->recvq == NULL) {
+		rv = -ENOMEM;
+		goto err_out;
+	}
+	if (udata) {
+		struct siw_uresp_create_srq uresp = {};
+
+		srq->xa_srq_index = siw_create_uobj(
+			ctx, srq->recvq, srq->num_rqe * sizeof(struct siw_rqe));
+
+		if (srq->xa_srq_index == SIW_INVAL_UOBJ_KEY) {
+			rv = -ENOMEM;
+			goto err_out;
+		}
+		uresp.srq_key = srq->xa_srq_index;
+		uresp.num_rqe = srq->num_rqe;
+
+		if (udata->outlen < sizeof(uresp)) {
+			rv = -EINVAL;
+			goto err_out;
+		}
+		rv = ib_copy_to_udata(udata, &uresp, sizeof(uresp));
+		if (rv)
+			goto err_out;
+	}
+	spin_lock_init(&srq->lock);
+
+	siw_dbg_pd(base_srq->pd, "[SRQ 0x%p]: success\n", srq);
+
+	return 0;
+
+err_out:
+	if (srq->recvq) {
+		if (ctx && srq->xa_srq_index != SIW_INVAL_UOBJ_KEY)
+			kfree(xa_erase(&ctx->xa, srq->xa_srq_index));
+		vfree(srq->recvq);
+	}
+	atomic_dec(&sdev->num_srq);
+
+	return rv;
+}
+
+/*
+ * siw_modify_srq()
+ *
+ * Modify SRQ. The caller may resize SRQ and/or set/reset notification
+ * limit and (re)arm IB_EVENT_SRQ_LIMIT_REACHED notification.
+ *
+ * NOTE: it is unclear if RDMA core allows for changing the MAX_SGE
+ * parameter. siw_modify_srq() does not check the attrs->max_sge param.
+ */
+int siw_modify_srq(struct ib_srq *base_srq, struct ib_srq_attr *attrs,
+		   enum ib_srq_attr_mask attr_mask, struct ib_udata *udata)
+{
+	struct siw_srq *srq = to_siw_srq(base_srq);
+	unsigned long flags;
+	int rv = 0;
+
+	spin_lock_irqsave(&srq->lock, flags);
+
+	if (attr_mask & IB_SRQ_MAX_WR) {
+		/* resize request not yet supported */
+		rv = -EOPNOTSUPP;
+		goto out;
+	}
+	if (attr_mask & IB_SRQ_LIMIT) {
+		if (attrs->srq_limit) {
+			if (unlikely(attrs->srq_limit > srq->num_rqe)) {
+				rv = -EINVAL;
+				goto out;
+			}
+			srq->armed = 1;
+		} else {
+			srq->armed = 0;
+		}
+		srq->limit = attrs->srq_limit;
+	}
+out:
+	spin_unlock_irqrestore(&srq->lock, flags);
+
+	return rv;
+}
+
+/*
+ * siw_query_srq()
+ *
+ * Query SRQ attributes.
+ */
+int siw_query_srq(struct ib_srq *base_srq, struct ib_srq_attr *attrs)
+{
+	struct siw_srq *srq = to_siw_srq(base_srq);
+	unsigned long flags;
+
+	spin_lock_irqsave(&srq->lock, flags);
+
+	attrs->max_wr = srq->num_rqe;
+	attrs->max_sge = srq->max_sge;
+	attrs->srq_limit = srq->limit;
+
+	spin_unlock_irqrestore(&srq->lock, flags);
+
+	return 0;
+}
+
+/*
+ * siw_destroy_srq()
+ *
+ * Destroy SRQ.
+ * It is assumed that the SRQ is not referenced by any
+ * QP anymore - the code trusts the RDMA core environment to keep track
+ * of QP references.
+ */
+void siw_destroy_srq(struct ib_srq *base_srq, struct ib_udata *udata)
+{
+	struct siw_srq *srq = to_siw_srq(base_srq);
+	struct siw_device *sdev = to_siw_dev(base_srq->device);
+	struct siw_ucontext *ctx =
+		rdma_udata_to_drv_context(udata, struct siw_ucontext,
+					  base_ucontext);
+
+	if (ctx && srq->xa_srq_index != SIW_INVAL_UOBJ_KEY)
+		kfree(xa_erase(&ctx->xa, srq->xa_srq_index));
+
+	vfree(srq->recvq);
+	atomic_dec(&sdev->num_srq);
+}
+
+/*
+ * siw_post_srq_recv()
+ *
+ * Post a list of receive queue elements to SRQ.
+ * NOTE: The function does not check or lock a certain SRQ state
+ *       during the post operation. The code simply trusts the
+ *       RDMA core environment.
+ *
+ * @base_srq:	Base SRQ contained in siw SRQ
+ * @wr:		List of R-WR's
+ * @bad_wr:	Updated to failing WR if posting fails.
+ */
+int siw_post_srq_recv(struct ib_srq *base_srq, const struct ib_recv_wr *wr,
+		      const struct ib_recv_wr **bad_wr)
+{
+	struct siw_srq *srq = to_siw_srq(base_srq);
+	unsigned long flags;
+	int rv = 0;
+
+	if (unlikely(!srq->kernel_verbs)) {
+		siw_dbg_pd(base_srq->pd,
+			   "[SRQ 0x%p]: no kernel post_recv for mapped srq\n",
+			   srq);
+		rv = -EINVAL;
+		goto out;
+	}
+	/*
+	 * Serialize potentially multiple producers.
+	 * Also needed to serialize potentially multiple
+	 * consumers.
+	 */
+	spin_lock_irqsave(&srq->lock, flags);
+
+	while (wr) {
+		u32 idx = srq->rq_put % srq->num_rqe;
+		struct siw_rqe *rqe = &srq->recvq[idx];
+
+		if (rqe->flags) {
+			siw_dbg_pd(base_srq->pd, "SRQ full\n");
+			rv = -ENOMEM;
+			break;
+		}
+		if (unlikely(wr->num_sge > srq->max_sge)) {
+			siw_dbg_pd(base_srq->pd,
+				   "[SRQ 0x%p]: too many sge's: %d\n", srq,
+				   wr->num_sge);
+			rv = -EINVAL;
+			break;
+		}
+		rqe->id = wr->wr_id;
+		rqe->num_sge = wr->num_sge;
+		siw_copy_sgl(wr->sg_list, rqe->sge, wr->num_sge);
+
+		/* Make sure S-RQE is completely written before valid */
+		smp_wmb();
+
+		rqe->flags = SIW_WQE_VALID;
+
+		srq->rq_put++;
+		wr = wr->next;
+	}
+	spin_unlock_irqrestore(&srq->lock, flags);
+out:
+	if (unlikely(rv < 0)) {
+		siw_dbg_pd(base_srq->pd, "[SRQ 0x%p]: error %d\n", srq, rv);
+		*bad_wr = wr;
+	}
+	return rv;
+}
+
+void siw_qp_event(struct siw_qp *qp, enum ib_event_type etype)
+{
+	struct ib_event event;
+	struct ib_qp *base_qp = qp->ib_qp;
+
+	/*
+	 * Do not report asynchronous errors on QP which gets
+	 * destroyed via verbs interface (siw_destroy_qp())
+	 */
+	if (qp->attrs.flags & SIW_QP_IN_DESTROY)
+		return;
+
+	event.event = etype;
+	event.device = base_qp->device;
+	event.element.qp = base_qp;
+
+	if (base_qp->event_handler) {
+		siw_dbg_qp(qp, "reporting event %d\n", etype);
+		base_qp->event_handler(&event, base_qp->qp_context);
+	}
+}
+
+void siw_cq_event(struct siw_cq *cq, enum ib_event_type etype)
+{
+	struct ib_event event;
+	struct ib_cq *base_cq = &cq->base_cq;
+
+	event.event = etype;
+	event.device = base_cq->device;
+	event.element.cq = base_cq;
+
+	if (base_cq->event_handler) {
+		siw_dbg_cq(cq, "reporting CQ event %d\n", etype);
+		base_cq->event_handler(&event, base_cq->cq_context);
+	}
+}
+
+void siw_srq_event(struct siw_srq *srq, enum ib_event_type etype)
+{
+	struct ib_event event;
+	struct ib_srq *base_srq = &srq->base_srq;
+
+	event.event = etype;
+	event.device = base_srq->device;
+	event.element.srq = base_srq;
+
+	if (base_srq->event_handler) {
+		siw_dbg_pd(srq->base_srq.pd,
+			   "reporting SRQ event %d\n", etype);
+		base_srq->event_handler(&event, base_srq->srq_context);
+	}
+}
+
+void siw_port_event(struct siw_device *sdev, u8 port, enum ib_event_type etype)
+{
+	struct ib_event event;
+
+	event.event = etype;
+	event.device = &sdev->base_dev;
+	event.element.port_num = port;
+
+	siw_dbg(&sdev->base_dev, "reporting port event %d\n", etype);
+
+	ib_dispatch_event(&event);
+}
diff --git a/drivers/infiniband/sw/siw/siw_verbs.h b/drivers/infiniband/sw/siw/siw_verbs.h
new file mode 100644
index 000000000000..1910869281cb
--- /dev/null
+++ b/drivers/infiniband/sw/siw/siw_verbs.h
@@ -0,0 +1,91 @@
+/* SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause */
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+
+#ifndef _SIW_VERBS_H
+#define _SIW_VERBS_H
+
+#include <linux/errno.h>
+
+#include <rdma/iw_cm.h>
+#include <rdma/ib_verbs.h>
+#include <rdma/ib_user_verbs.h>
+
+#include "siw.h"
+#include "siw_cm.h"
+
+/*
+ * siw_copy_sgl()
+ *
+ * Copy SGL from RDMA core representation to local
+ * representation.
+ */
+static inline void siw_copy_sgl(struct ib_sge *sge, struct siw_sge *siw_sge,
+				int num_sge)
+{
+	while (num_sge--) {
+		siw_sge->laddr = sge->addr;
+		siw_sge->length = sge->length;
+		siw_sge->lkey = sge->lkey;
+
+		siw_sge++;
+		sge++;
+	}
+}
+
+int siw_alloc_ucontext(struct ib_ucontext *base_ctx, struct ib_udata *udata);
+void siw_dealloc_ucontext(struct ib_ucontext *base_ctx);
+int siw_query_port(struct ib_device *base_dev, u8 port,
+		   struct ib_port_attr *attr);
+int siw_get_port_immutable(struct ib_device *base_dev, u8 port,
+			   struct ib_port_immutable *port_immutable);
+int siw_query_device(struct ib_device *base_dev, struct ib_device_attr *attr,
+		     struct ib_udata *udata);
+int siw_create_cq(struct ib_cq *base_cq, const struct ib_cq_init_attr *attr,
+		  struct ib_udata *udata);
+int siw_query_port(struct ib_device *base_dev, u8 port,
+		   struct ib_port_attr *attr);
+int siw_query_pkey(struct ib_device *base_dev, u8 port, u16 idx, u16 *pkey);
+int siw_query_gid(struct ib_device *base_dev, u8 port, int idx,
+		  union ib_gid *gid);
+int siw_alloc_pd(struct ib_pd *base_pd, struct ib_udata *udata);
+void siw_dealloc_pd(struct ib_pd *base_pd, struct ib_udata *udata);
+struct ib_qp *siw_create_qp(struct ib_pd *base_pd,
+			    struct ib_qp_init_attr *attr,
+			    struct ib_udata *udata);
+int siw_query_qp(struct ib_qp *base_qp, struct ib_qp_attr *qp_attr,
+		 int qp_attr_mask, struct ib_qp_init_attr *qp_init_attr);
+int siw_verbs_modify_qp(struct ib_qp *base_qp, struct ib_qp_attr *attr,
+			int attr_mask, struct ib_udata *udata);
+int siw_destroy_qp(struct ib_qp *base_qp, struct ib_udata *udata);
+int siw_post_send(struct ib_qp *base_qp, const struct ib_send_wr *wr,
+		  const struct ib_send_wr **bad_wr);
+int siw_post_receive(struct ib_qp *base_qp, const struct ib_recv_wr *wr,
+		     const struct ib_recv_wr **bad_wr);
+void siw_destroy_cq(struct ib_cq *base_cq, struct ib_udata *udata);
+int siw_poll_cq(struct ib_cq *base_cq, int num_entries, struct ib_wc *wc);
+int siw_req_notify_cq(struct ib_cq *base_cq, enum ib_cq_notify_flags flags);
+struct ib_mr *siw_reg_user_mr(struct ib_pd *base_pd, u64 start, u64 len,
+			      u64 rnic_va, int rights, struct ib_udata *udata);
+struct ib_mr *siw_alloc_mr(struct ib_pd *base_pd, enum ib_mr_type mr_type,
+			   u32 max_sge, struct ib_udata *udata);
+struct ib_mr *siw_get_dma_mr(struct ib_pd *base_pd, int rights);
+int siw_map_mr_sg(struct ib_mr *base_mr, struct scatterlist *sl, int num_sle,
+		  unsigned int *sg_off);
+int siw_dereg_mr(struct ib_mr *base_mr, struct ib_udata *udata);
+int siw_create_srq(struct ib_srq *base_srq, struct ib_srq_init_attr *attr,
+		   struct ib_udata *udata);
+int siw_modify_srq(struct ib_srq *base_srq, struct ib_srq_attr *attr,
+		   enum ib_srq_attr_mask mask, struct ib_udata *udata);
+int siw_query_srq(struct ib_srq *base_srq, struct ib_srq_attr *attr);
+void siw_destroy_srq(struct ib_srq *base_srq, struct ib_udata *udata);
+int siw_post_srq_recv(struct ib_srq *base_srq, const struct ib_recv_wr *wr,
+		      const struct ib_recv_wr **bad_wr);
+int siw_mmap(struct ib_ucontext *ctx, struct vm_area_struct *vma);
+void siw_qp_event(struct siw_qp *qp, enum ib_event_type type);
+void siw_cq_event(struct siw_cq *cq, enum ib_event_type type);
+void siw_srq_event(struct siw_srq *srq, enum ib_event_type type);
+void siw_port_event(struct siw_device *dev, u8 port, enum ib_event_type type);
+
+#endif
diff --git a/include/uapi/rdma/rdma_user_ioctl_cmds.h b/include/uapi/rdma/rdma_user_ioctl_cmds.h
index 26213f49f5c8..64c14cb0022f 100644
--- a/include/uapi/rdma/rdma_user_ioctl_cmds.h
+++ b/include/uapi/rdma/rdma_user_ioctl_cmds.h
@@ -103,6 +103,7 @@ enum rdma_driver_id {
 	RDMA_DRIVER_HFI1,
 	RDMA_DRIVER_QIB,
 	RDMA_DRIVER_EFA,
+	RDMA_DRIVER_SIW,
 };
 
 #endif
diff --git a/include/uapi/rdma/siw-abi.h b/include/uapi/rdma/siw-abi.h
new file mode 100644
index 000000000000..3dd8071ace7b
--- /dev/null
+++ b/include/uapi/rdma/siw-abi.h
@@ -0,0 +1,185 @@
+/* SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause */
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+
+#ifndef _SIW_USER_H
+#define _SIW_USER_H
+
+#include <linux/types.h>
+
+#define SIW_NODE_DESC_COMMON "Software iWARP stack"
+#define SIW_ABI_VERSION 1
+#define SIW_MAX_SGE 6
+#define SIW_UOBJ_MAX_KEY 0x08FFFF
+#define SIW_INVAL_UOBJ_KEY (SIW_UOBJ_MAX_KEY + 1)
+
+struct siw_uresp_create_cq {
+	__u32 cq_id;
+	__u32 num_cqe;
+	__aligned_u64 cq_key;
+};
+
+struct siw_uresp_create_qp {
+	__u32 qp_id;
+	__u32 num_sqe;
+	__u32 num_rqe;
+	__u32 pad;
+	__aligned_u64 sq_key;
+	__aligned_u64 rq_key;
+};
+
+struct siw_ureq_reg_mr {
+	__u8 stag_key;
+	__u8 reserved[3];
+	__u32 pad;
+};
+
+struct siw_uresp_reg_mr {
+	__u32 stag;
+	__u32 pad;
+};
+
+struct siw_uresp_create_srq {
+	__u32 num_rqe;
+	__u32 pad;
+	__aligned_u64 srq_key;
+};
+
+struct siw_uresp_alloc_ctx {
+	__u32 dev_id;
+	__u32 pad;
+};
+
+enum siw_opcode {
+	SIW_OP_WRITE,
+	SIW_OP_READ,
+	SIW_OP_READ_LOCAL_INV,
+	SIW_OP_SEND,
+	SIW_OP_SEND_WITH_IMM,
+	SIW_OP_SEND_REMOTE_INV,
+
+	/* Unsupported */
+	SIW_OP_FETCH_AND_ADD,
+	SIW_OP_COMP_AND_SWAP,
+
+	SIW_OP_RECEIVE,
+	/* provider internal SQE */
+	SIW_OP_READ_RESPONSE,
+	/*
+	 * below opcodes valid for
+	 * in-kernel clients only
+	 */
+	SIW_OP_INVAL_STAG,
+	SIW_OP_REG_MR,
+	SIW_NUM_OPCODES
+};
+
+/* Keep it same as ibv_sge to allow for memcpy */
+struct siw_sge {
+	__aligned_u64 laddr;
+	__u32 length;
+	__u32 lkey;
+};
+
+/*
+ * Inline data are kept within the work request itself occupying
+ * the space of sge[1] .. sge[n]. Therefore, inline data cannot be
+ * supported if SIW_MAX_SGE is below 2 elements.
+ */
+#define SIW_MAX_INLINE (sizeof(struct siw_sge) * (SIW_MAX_SGE - 1))
+
+#if SIW_MAX_SGE < 2
+#error "SIW_MAX_SGE must be at least 2"
+#endif
+
+enum siw_wqe_flags {
+	SIW_WQE_VALID = 1,
+	SIW_WQE_INLINE = (1 << 1),
+	SIW_WQE_SIGNALLED = (1 << 2),
+	SIW_WQE_SOLICITED = (1 << 3),
+	SIW_WQE_READ_FENCE = (1 << 4),
+	SIW_WQE_REM_INVAL = (1 << 5),
+	SIW_WQE_COMPLETED = (1 << 6)
+};
+
+/* Send Queue Element */
+struct siw_sqe {
+	__aligned_u64 id;
+	__u16 flags;
+	__u8 num_sge;
+	/* Contains enum siw_opcode values */
+	__u8 opcode;
+	__u32 rkey;
+	union {
+		__aligned_u64 raddr;
+		__aligned_u64 base_mr;
+	};
+	union {
+		struct siw_sge sge[SIW_MAX_SGE];
+		__aligned_u64 access;
+	};
+};
+
+/* Receive Queue Element */
+struct siw_rqe {
+	__aligned_u64 id;
+	__u16 flags;
+	__u8 num_sge;
+	/*
+	 * only used by kernel driver,
+	 * ignored if set by user
+	 */
+	__u8 opcode;
+	__u32 unused;
+	struct siw_sge sge[SIW_MAX_SGE];
+};
+
+enum siw_notify_flags {
+	SIW_NOTIFY_NOT = (0),
+	SIW_NOTIFY_SOLICITED = (1 << 0),
+	SIW_NOTIFY_NEXT_COMPLETION = (1 << 1),
+	SIW_NOTIFY_MISSED_EVENTS = (1 << 2),
+	SIW_NOTIFY_ALL = SIW_NOTIFY_SOLICITED | SIW_NOTIFY_NEXT_COMPLETION |
+			 SIW_NOTIFY_MISSED_EVENTS
+};
+
+enum siw_wc_status {
+	SIW_WC_SUCCESS,
+	SIW_WC_LOC_LEN_ERR,
+	SIW_WC_LOC_PROT_ERR,
+	SIW_WC_LOC_QP_OP_ERR,
+	SIW_WC_WR_FLUSH_ERR,
+	SIW_WC_BAD_RESP_ERR,
+	SIW_WC_LOC_ACCESS_ERR,
+	SIW_WC_REM_ACCESS_ERR,
+	SIW_WC_REM_INV_REQ_ERR,
+	SIW_WC_GENERAL_ERR,
+	SIW_NUM_WC_STATUS
+};
+
+struct siw_cqe {
+	__aligned_u64 id;
+	__u8 flags;
+	__u8 opcode;
+	__u16 status;
+	__u32 bytes;
+	union {
+		__aligned_u64 imm_data;
+		__u32 inval_stag;
+	};
+	/* QP number or QP pointer */
+	union {
+		struct ib_qp *base_qp;
+		__aligned_u64 qp_id;
+	};
+};
+
+/*
+ * Shared structure between user and kernel
+ * to control CQ arming.
+ */
+struct siw_cq_ctrl {
+	__aligned_u64 notify;
+};
+#endif