/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */ /* * Copyright (c) 2014-2017 Oracle. All rights reserved. * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU * General Public License (GPL) Version 2, available from the file * COPYING in the main directory of this source tree, or the BSD-type * license below: * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials provided * with the distribution. * * Neither the name of the Network Appliance, Inc. nor the names of * its contributors may be used to endorse or promote products * derived from this software without specific prior written * permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #ifndef _LINUX_SUNRPC_XPRT_RDMA_H #define _LINUX_SUNRPC_XPRT_RDMA_H #include /* wait_queue_head_t, etc */ #include /* spinlock_t, etc */ #include /* atomic_t, etc */ #include /* struct work_struct */ #include /* RDMA connection api */ #include /* RDMA verbs api */ #include /* rpc_xprt */ #include /* RPC/RDMA protocol */ #include /* xprt parameters */ #define RDMA_RESOLVE_TIMEOUT (5000) /* 5 seconds */ #define RDMA_CONNECT_RETRY_MAX (2) /* retries if no listener backlog */ #define RPCRDMA_BIND_TO (60U * HZ) #define RPCRDMA_INIT_REEST_TO (5U * HZ) #define RPCRDMA_MAX_REEST_TO (30U * HZ) #define RPCRDMA_IDLE_DISC_TO (5U * 60 * HZ) /* * Interface Adapter -- one per transport instance */ struct rpcrdma_ia { struct ib_device *ri_device; struct rdma_cm_id *ri_id; struct ib_pd *ri_pd; struct completion ri_done; struct completion ri_remove_done; int ri_async_rc; unsigned int ri_max_segs; unsigned int ri_max_frwr_depth; unsigned int ri_max_inline_write; unsigned int ri_max_inline_read; unsigned int ri_max_send_sges; bool ri_implicit_roundup; enum ib_mr_type ri_mrtype; unsigned long ri_flags; }; enum { RPCRDMA_IAF_REMOVING = 0, }; /* * RDMA Endpoint -- one per transport instance */ struct rpcrdma_ep { unsigned int rep_send_count; unsigned int rep_send_batch; int rep_connected; struct ib_qp_init_attr rep_attr; wait_queue_head_t rep_connect_wait; struct rpcrdma_connect_private rep_cm_private; struct rdma_conn_param rep_remote_cma; int rep_receive_count; }; /* Pre-allocate extra Work Requests for handling backward receives * and sends. This is a fixed value because the Work Queues are * allocated when the forward channel is set up. */ #if defined(CONFIG_SUNRPC_BACKCHANNEL) #define RPCRDMA_BACKWARD_WRS (8) #else #define RPCRDMA_BACKWARD_WRS (0) #endif /* Registered buffer -- registered kmalloc'd memory for RDMA SEND/RECV * * The below structure appears at the front of a large region of kmalloc'd * memory, which always starts on a good alignment boundary. */ struct rpcrdma_regbuf { struct ib_sge rg_iov; struct ib_device *rg_device; enum dma_data_direction rg_direction; __be32 rg_base[0] __attribute__ ((aligned(256))); }; static inline u64 rdmab_addr(struct rpcrdma_regbuf *rb) { return rb->rg_iov.addr; } static inline u32 rdmab_length(struct rpcrdma_regbuf *rb) { return rb->rg_iov.length; } static inline u32 rdmab_lkey(struct rpcrdma_regbuf *rb) { return rb->rg_iov.lkey; } static inline struct ib_device * rdmab_device(struct rpcrdma_regbuf *rb) { return rb->rg_device; } #define RPCRDMA_DEF_GFP (GFP_NOIO | __GFP_NOWARN) /* To ensure a transport can always make forward progress, * the number of RDMA segments allowed in header chunk lists * is capped at 8. This prevents less-capable devices and * memory registrations from overrunning the Send buffer * while building chunk lists. * * Elements of the Read list take up more room than the * Write list or Reply chunk. 8 read segments means the Read * list (or Write list or Reply chunk) cannot consume more * than * * ((8 + 2) * read segment size) + 1 XDR words, or 244 bytes. * * And the fixed part of the header is another 24 bytes. * * The smallest inline threshold is 1024 bytes, ensuring that * at least 750 bytes are available for RPC messages. */ enum { RPCRDMA_MAX_HDR_SEGS = 8, RPCRDMA_HDRBUF_SIZE = 256, }; /* * struct rpcrdma_rep -- this structure encapsulates state required * to receive and complete an RPC Reply, asychronously. It needs * several pieces of state: * * o receive buffer and ib_sge (donated to provider) * o status of receive (success or not, length, inv rkey) * o bookkeeping state to get run by reply handler (XDR stream) * * These structures are allocated during transport initialization. * N of these are associated with a transport instance, managed by * struct rpcrdma_buffer. N is the max number of outstanding RPCs. */ struct rpcrdma_rep { struct ib_cqe rr_cqe; __be32 rr_xid; __be32 rr_vers; __be32 rr_proc; int rr_wc_flags; u32 rr_inv_rkey; bool rr_temp; struct rpcrdma_regbuf *rr_rdmabuf; struct rpcrdma_xprt *rr_rxprt; struct work_struct rr_work; struct xdr_buf rr_hdrbuf; struct xdr_stream rr_stream; struct rpc_rqst *rr_rqst; struct list_head rr_list; struct ib_recv_wr rr_recv_wr; }; /* struct rpcrdma_sendctx - DMA mapped SGEs to unmap after Send completes */ struct rpcrdma_req; struct rpcrdma_xprt; struct rpcrdma_sendctx { struct ib_send_wr sc_wr; struct ib_cqe sc_cqe; struct rpcrdma_xprt *sc_xprt; struct rpcrdma_req *sc_req; unsigned int sc_unmap_count; struct ib_sge sc_sges[]; }; /* Limit the number of SGEs that can be unmapped during one * Send completion. This caps the amount of work a single * completion can do before returning to the provider. * * Setting this to zero disables Send completion batching. */ enum { RPCRDMA_MAX_SEND_BATCH = 7, }; /* * struct rpcrdma_mr - external memory region metadata * * An external memory region is any buffer or page that is registered * on the fly (ie, not pre-registered). * * Each rpcrdma_buffer has a list of free MWs anchored in rb_mrs. During * call_allocate, rpcrdma_buffer_get() assigns one to each segment in * an rpcrdma_req. Then rpcrdma_register_external() grabs these to keep * track of registration metadata while each RPC is pending. * rpcrdma_deregister_external() uses this metadata to unmap and * release these resources when an RPC is complete. */ enum rpcrdma_frwr_state { FRWR_IS_INVALID, /* ready to be used */ FRWR_IS_VALID, /* in use */ FRWR_FLUSHED_FR, /* flushed FASTREG WR */ FRWR_FLUSHED_LI, /* flushed LOCALINV WR */ }; struct rpcrdma_frwr { struct ib_mr *fr_mr; struct ib_cqe fr_cqe; enum rpcrdma_frwr_state fr_state; struct completion fr_linv_done; union { struct ib_reg_wr fr_regwr; struct ib_send_wr fr_invwr; }; }; struct rpcrdma_mr { struct list_head mr_list; struct scatterlist *mr_sg; int mr_nents; enum dma_data_direction mr_dir; struct rpcrdma_frwr frwr; struct rpcrdma_xprt *mr_xprt; u32 mr_handle; u32 mr_length; u64 mr_offset; struct work_struct mr_recycle; struct list_head mr_all; }; /* * struct rpcrdma_req -- structure central to the request/reply sequence. * * N of these are associated with a transport instance, and stored in * struct rpcrdma_buffer. N is the max number of outstanding requests. * * It includes pre-registered buffer memory for send AND recv. * The recv buffer, however, is not owned by this structure, and * is "donated" to the hardware when a recv is posted. When a * reply is handled, the recv buffer used is given back to the * struct rpcrdma_req associated with the request. * * In addition to the basic memory, this structure includes an array * of iovs for send operations. The reason is that the iovs passed to * ib_post_{send,recv} must not be modified until the work request * completes. */ /* Maximum number of page-sized "segments" per chunk list to be * registered or invalidated. Must handle a Reply chunk: */ enum { RPCRDMA_MAX_IOV_SEGS = 3, RPCRDMA_MAX_DATA_SEGS = ((1 * 1024 * 1024) / PAGE_SIZE) + 1, RPCRDMA_MAX_SEGS = RPCRDMA_MAX_DATA_SEGS + RPCRDMA_MAX_IOV_SEGS, }; struct rpcrdma_mr_seg { /* chunk descriptors */ u32 mr_len; /* length of chunk or segment */ struct page *mr_page; /* owning page, if any */ char *mr_offset; /* kva if no page, else offset */ }; /* The Send SGE array is provisioned to send a maximum size * inline request: * - RPC-over-RDMA header * - xdr_buf head iovec * - RPCRDMA_MAX_INLINE bytes, in pages * - xdr_buf tail iovec * * The actual number of array elements consumed by each RPC * depends on the device's max_sge limit. */ enum { RPCRDMA_MIN_SEND_SGES = 3, RPCRDMA_MAX_PAGE_SGES = RPCRDMA_MAX_INLINE >> PAGE_SHIFT, RPCRDMA_MAX_SEND_SGES = 1 + 1 + RPCRDMA_MAX_PAGE_SGES + 1, }; struct rpcrdma_buffer; struct rpcrdma_req { struct list_head rl_list; struct rpc_rqst rl_slot; struct rpcrdma_buffer *rl_buffer; struct rpcrdma_rep *rl_reply; struct xdr_stream rl_stream; struct xdr_buf rl_hdrbuf; struct rpcrdma_sendctx *rl_sendctx; struct rpcrdma_regbuf *rl_rdmabuf; /* xprt header */ struct rpcrdma_regbuf *rl_sendbuf; /* rq_snd_buf */ struct rpcrdma_regbuf *rl_recvbuf; /* rq_rcv_buf */ struct list_head rl_all; unsigned long rl_flags; struct list_head rl_registered; /* registered segments */ struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS]; }; /* rl_flags */ enum { RPCRDMA_REQ_F_PENDING = 0, RPCRDMA_REQ_F_TX_RESOURCES, }; static inline struct rpcrdma_req * rpcr_to_rdmar(const struct rpc_rqst *rqst) { return container_of(rqst, struct rpcrdma_req, rl_slot); } static inline void rpcrdma_mr_push(struct rpcrdma_mr *mr, struct list_head *list) { list_add_tail(&mr->mr_list, list); } static inline struct rpcrdma_mr * rpcrdma_mr_pop(struct list_head *list) { struct rpcrdma_mr *mr; mr = list_first_entry(list, struct rpcrdma_mr, mr_list); list_del_init(&mr->mr_list); return mr; } /* * struct rpcrdma_buffer -- holds list/queue of pre-registered memory for * inline requests/replies, and client/server credits. * * One of these is associated with a transport instance */ struct rpcrdma_buffer { spinlock_t rb_mrlock; /* protect rb_mrs list */ struct list_head rb_mrs; struct list_head rb_all; unsigned long rb_sc_head; unsigned long rb_sc_tail; unsigned long rb_sc_last; struct rpcrdma_sendctx **rb_sc_ctxs; spinlock_t rb_lock; /* protect buf lists */ struct list_head rb_send_bufs; struct list_head rb_recv_bufs; struct list_head rb_allreqs; unsigned long rb_flags; u32 rb_max_requests; u32 rb_credits; /* most recent credit grant */ u32 rb_bc_srv_max_requests; u32 rb_bc_max_requests; struct workqueue_struct *rb_completion_wq; struct delayed_work rb_refresh_worker; }; /* rb_flags */ enum { RPCRDMA_BUF_F_EMPTY_SCQ = 0, }; /* * Internal structure for transport instance creation. This * exists primarily for modularity. * * This data should be set with mount options */ struct rpcrdma_create_data_internal { unsigned int max_requests; /* max requests (slots) in flight */ unsigned int rsize; /* mount rsize - max read hdr+data */ unsigned int wsize; /* mount wsize - max write hdr+data */ unsigned int inline_rsize; /* max non-rdma read data payload */ unsigned int inline_wsize; /* max non-rdma write data payload */ }; /* * Statistics for RPCRDMA */ struct rpcrdma_stats { /* accessed when sending a call */ unsigned long read_chunk_count; unsigned long write_chunk_count; unsigned long reply_chunk_count; unsigned long long total_rdma_request; /* rarely accessed error counters */ unsigned long long pullup_copy_count; unsigned long hardway_register_count; unsigned long failed_marshal_count; unsigned long bad_reply_count; unsigned long mrs_recycled; unsigned long mrs_orphaned; unsigned long mrs_allocated; unsigned long empty_sendctx_q; /* accessed when receiving a reply */ unsigned long long total_rdma_reply; unsigned long long fixup_copy_count; unsigned long reply_waits_for_send; unsigned long local_inv_needed; unsigned long nomsg_call_count; unsigned long bcall_count; }; /* * RPCRDMA transport -- encapsulates the structures above for * integration with RPC. * * The contained structures are embedded, not pointers, * for convenience. This structure need not be visible externally. * * It is allocated and initialized during mount, and released * during unmount. */ struct rpcrdma_xprt { struct rpc_xprt rx_xprt; struct rpcrdma_ia rx_ia; struct rpcrdma_ep rx_ep; struct rpcrdma_buffer rx_buf; struct rpcrdma_create_data_internal rx_data; struct delayed_work rx_connect_worker; struct rpcrdma_stats rx_stats; }; #define rpcx_to_rdmax(x) container_of(x, struct rpcrdma_xprt, rx_xprt) #define rpcx_to_rdmad(x) (rpcx_to_rdmax(x)->rx_data) static inline const char * rpcrdma_addrstr(const struct rpcrdma_xprt *r_xprt) { return r_xprt->rx_xprt.address_strings[RPC_DISPLAY_ADDR]; } static inline const char * rpcrdma_portstr(const struct rpcrdma_xprt *r_xprt) { return r_xprt->rx_xprt.address_strings[RPC_DISPLAY_PORT]; } /* Setting this to 0 ensures interoperability with early servers. * Setting this to 1 enhances certain unaligned read/write performance. * Default is 0, see sysctl entry and rpc_rdma.c rpcrdma_convert_iovs() */ extern int xprt_rdma_pad_optimize; /* This setting controls the hunt for a supported memory * registration strategy. */ extern unsigned int xprt_rdma_memreg_strategy; /* * Interface Adapter calls - xprtrdma/verbs.c */ int rpcrdma_ia_open(struct rpcrdma_xprt *xprt); void rpcrdma_ia_remove(struct rpcrdma_ia *ia); void rpcrdma_ia_close(struct rpcrdma_ia *); /* * Endpoint calls - xprtrdma/verbs.c */ int rpcrdma_ep_create(struct rpcrdma_ep *, struct rpcrdma_ia *, struct rpcrdma_create_data_internal *); void rpcrdma_ep_destroy(struct rpcrdma_ep *, struct rpcrdma_ia *); int rpcrdma_ep_connect(struct rpcrdma_ep *, struct rpcrdma_ia *); void rpcrdma_ep_disconnect(struct rpcrdma_ep *, struct rpcrdma_ia *); int rpcrdma_ep_post(struct rpcrdma_ia *, struct rpcrdma_ep *, struct rpcrdma_req *); /* * Buffer calls - xprtrdma/verbs.c */ struct rpcrdma_req *rpcrdma_create_req(struct rpcrdma_xprt *); void rpcrdma_req_destroy(struct rpcrdma_req *req); int rpcrdma_buffer_create(struct rpcrdma_xprt *); void rpcrdma_buffer_destroy(struct rpcrdma_buffer *); struct rpcrdma_sendctx *rpcrdma_sendctx_get_locked(struct rpcrdma_buffer *buf); struct rpcrdma_mr *rpcrdma_mr_get(struct rpcrdma_xprt *r_xprt); void rpcrdma_mr_put(struct rpcrdma_mr *mr); void rpcrdma_mr_unmap_and_put(struct rpcrdma_mr *mr); static inline void rpcrdma_mr_recycle(struct rpcrdma_mr *mr) { schedule_work(&mr->mr_recycle); } struct rpcrdma_req *rpcrdma_buffer_get(struct rpcrdma_buffer *); void rpcrdma_buffer_put(struct rpcrdma_req *); void rpcrdma_recv_buffer_put(struct rpcrdma_rep *); struct rpcrdma_regbuf *rpcrdma_alloc_regbuf(size_t, enum dma_data_direction, gfp_t); bool __rpcrdma_dma_map_regbuf(struct rpcrdma_ia *, struct rpcrdma_regbuf *); void rpcrdma_free_regbuf(struct rpcrdma_regbuf *); static inline bool rpcrdma_regbuf_is_mapped(struct rpcrdma_regbuf *rb) { return rb->rg_device != NULL; } static inline bool rpcrdma_dma_map_regbuf(struct rpcrdma_ia *ia, struct rpcrdma_regbuf *rb) { if (likely(rpcrdma_regbuf_is_mapped(rb))) return true; return __rpcrdma_dma_map_regbuf(ia, rb); } /* * Wrappers for chunk registration, shared by read/write chunk code. */ static inline enum dma_data_direction rpcrdma_data_dir(bool writing) { return writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE; } /* Memory registration calls xprtrdma/frwr_ops.c */ bool frwr_is_supported(struct rpcrdma_ia *); int frwr_open(struct rpcrdma_ia *ia, struct rpcrdma_ep *ep, struct rpcrdma_create_data_internal *cdata); int frwr_init_mr(struct rpcrdma_ia *ia, struct rpcrdma_mr *mr); void frwr_release_mr(struct rpcrdma_mr *mr); size_t frwr_maxpages(struct rpcrdma_xprt *r_xprt); struct rpcrdma_mr_seg *frwr_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg, int nsegs, bool writing, u32 xid, struct rpcrdma_mr **mr); int frwr_send(struct rpcrdma_ia *ia, struct rpcrdma_req *req); void frwr_reminv(struct rpcrdma_rep *rep, struct list_head *mrs); void frwr_unmap_sync(struct rpcrdma_xprt *r_xprt, struct list_head *mrs); /* * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c */ enum rpcrdma_chunktype { rpcrdma_noch = 0, rpcrdma_readch, rpcrdma_areadch, rpcrdma_writech, rpcrdma_replych }; int rpcrdma_prepare_send_sges(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req, u32 hdrlen, struct xdr_buf *xdr, enum rpcrdma_chunktype rtype); void rpcrdma_unmap_sendctx(struct rpcrdma_sendctx *sc); int rpcrdma_marshal_req(struct rpcrdma_xprt *r_xprt, struct rpc_rqst *rqst); void rpcrdma_set_max_header_sizes(struct rpcrdma_xprt *); void rpcrdma_complete_rqst(struct rpcrdma_rep *rep); void rpcrdma_reply_handler(struct rpcrdma_rep *rep); void rpcrdma_release_rqst(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req); void rpcrdma_deferred_completion(struct work_struct *work); static inline void rpcrdma_set_xdrlen(struct xdr_buf *xdr, size_t len) { xdr->head[0].iov_len = len; xdr->len = len; } /* RPC/RDMA module init - xprtrdma/transport.c */ extern unsigned int xprt_rdma_max_inline_read; void xprt_rdma_format_addresses(struct rpc_xprt *xprt, struct sockaddr *sap); void xprt_rdma_free_addresses(struct rpc_xprt *xprt); void xprt_rdma_close(struct rpc_xprt *xprt); void xprt_rdma_print_stats(struct rpc_xprt *xprt, struct seq_file *seq); int xprt_rdma_init(void); void xprt_rdma_cleanup(void); /* Backchannel calls - xprtrdma/backchannel.c */ #if defined(CONFIG_SUNRPC_BACKCHANNEL) int xprt_rdma_bc_setup(struct rpc_xprt *, unsigned int); size_t xprt_rdma_bc_maxpayload(struct rpc_xprt *); int rpcrdma_bc_post_recv(struct rpcrdma_xprt *, unsigned int); void rpcrdma_bc_receive_call(struct rpcrdma_xprt *, struct rpcrdma_rep *); int xprt_rdma_bc_send_reply(struct rpc_rqst *rqst); void xprt_rdma_bc_free_rqst(struct rpc_rqst *); void xprt_rdma_bc_destroy(struct rpc_xprt *, unsigned int); #endif /* CONFIG_SUNRPC_BACKCHANNEL */ extern struct xprt_class xprt_rdma_bc; #endif /* _LINUX_SUNRPC_XPRT_RDMA_H */