iscsi-target: Add iSCSI fabric support for target v4.1

The Linux-iSCSI.org target module is a full featured in-kernel
software implementation of iSCSI target mode (RFC-3720) for the
current WIP mainline target v4.1 infrastructure code for the v3.1
kernel.  More information can be found here:

http://linux-iscsi.org/wiki/ISCSI

This includes support for:

   * RFC-3720 defined request / response state machines and support for
     all defined iSCSI operation codes from Section 10.2.1.2 using libiscsi
     include/scsi/iscsi_proto.h PDU definitions
   * Target v4.1 compatible control plane using the generic layout in
     target_core_fabric_configfs.c and fabric dependent attributes
     within /sys/kernel/config/target/iscsi/ subdirectories.
   * Target v4.1 compatible iSCSI statistics based on RFC-4544 (iSCSI MIBS)
   * Support for IPv6 and IPv4 network portals in M:N mapping to TPGs
   * iSCSI Error Recovery Hierarchy support
   * Per iSCSI connection RX/TX thread pair scheduling affinity
   * crc32c + crc32c_intel SSEv4 instruction offload support using libcrypto
   * CHAP Authentication support using libcrypto
   * Conversion to use internal SGl allocation with iscsit_alloc_buffs() ->
     transport_generic_map_mem_to_cmd()

(nab: Fix iscsi_proto.h struct scsi_lun usage from linux-next in commit:
      iscsi: Use struct scsi_lun in iscsi structs instead of u8[8])
(nab: Fix 32-bit compile warnings)

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andy Grover <agrover@redhat.com>
Acked-by: Roland Dreier <roland@kernel.org>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>

1 files changed, 531 insertions, 0 deletions

diff --git a/drivers/target/iscsi/iscsi_target_datain_values.c b/drivers/target/iscsi/iscsi_target_datain_values.c
new file mode 100644
index 000000000000..8c0495129513
--- /dev/null
+++ b/drivers/target/iscsi/iscsi_target_datain_values.c
@@ -0,0 +1,531 @@
+/*******************************************************************************
+ * This file contains the iSCSI Target DataIN value generation functions.
+ *
+ * \u00a9 Copyright 2007-2011 RisingTide Systems LLC.
+ *
+ * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
+ *
+ * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ ******************************************************************************/
+
+#include <scsi/iscsi_proto.h>
+
+#include "iscsi_target_core.h"
+#include "iscsi_target_seq_pdu_list.h"
+#include "iscsi_target_erl1.h"
+#include "iscsi_target_util.h"
+#include "iscsi_target.h"
+#include "iscsi_target_datain_values.h"
+
+struct iscsi_datain_req *iscsit_allocate_datain_req(void)
+{
+	struct iscsi_datain_req *dr;
+
+	dr = kmem_cache_zalloc(lio_dr_cache, GFP_ATOMIC);
+	if (!dr) {
+		pr_err("Unable to allocate memory for"
+				" struct iscsi_datain_req\n");
+		return NULL;
+	}
+	INIT_LIST_HEAD(&dr->dr_list);
+
+	return dr;
+}
+
+void iscsit_attach_datain_req(struct iscsi_cmd *cmd, struct iscsi_datain_req *dr)
+{
+	spin_lock(&cmd->datain_lock);
+	list_add_tail(&dr->dr_list, &cmd->datain_list);
+	spin_unlock(&cmd->datain_lock);
+}
+
+void iscsit_free_datain_req(struct iscsi_cmd *cmd, struct iscsi_datain_req *dr)
+{
+	spin_lock(&cmd->datain_lock);
+	list_del(&dr->dr_list);
+	spin_unlock(&cmd->datain_lock);
+
+	kmem_cache_free(lio_dr_cache, dr);
+}
+
+void iscsit_free_all_datain_reqs(struct iscsi_cmd *cmd)
+{
+	struct iscsi_datain_req *dr, *dr_tmp;
+
+	spin_lock(&cmd->datain_lock);
+	list_for_each_entry_safe(dr, dr_tmp, &cmd->datain_list, dr_list) {
+		list_del(&dr->dr_list);
+		kmem_cache_free(lio_dr_cache, dr);
+	}
+	spin_unlock(&cmd->datain_lock);
+}
+
+struct iscsi_datain_req *iscsit_get_datain_req(struct iscsi_cmd *cmd)
+{
+	struct iscsi_datain_req *dr;
+
+	if (list_empty(&cmd->datain_list)) {
+		pr_err("cmd->datain_list is empty for ITT:"
+			" 0x%08x\n", cmd->init_task_tag);
+		return NULL;
+	}
+	list_for_each_entry(dr, &cmd->datain_list, dr_list)
+		break;
+
+	return dr;
+}
+
+/*
+ *	For Normal and Recovery DataSequenceInOrder=Yes and DataPDUInOrder=Yes.
+ */
+static struct iscsi_datain_req *iscsit_set_datain_values_yes_and_yes(
+	struct iscsi_cmd *cmd,
+	struct iscsi_datain *datain)
+{
+	u32 next_burst_len, read_data_done, read_data_left;
+	struct iscsi_conn *conn = cmd->conn;
+	struct iscsi_datain_req *dr;
+
+	dr = iscsit_get_datain_req(cmd);
+	if (!dr)
+		return NULL;
+
+	if (dr->recovery && dr->generate_recovery_values) {
+		if (iscsit_create_recovery_datain_values_datasequenceinorder_yes(
+					cmd, dr) < 0)
+			return NULL;
+
+		dr->generate_recovery_values = 0;
+	}
+
+	next_burst_len = (!dr->recovery) ?
+			cmd->next_burst_len : dr->next_burst_len;
+	read_data_done = (!dr->recovery) ?
+			cmd->read_data_done : dr->read_data_done;
+
+	read_data_left = (cmd->data_length - read_data_done);
+	if (!read_data_left) {
+		pr_err("ITT: 0x%08x read_data_left is zero!\n",
+				cmd->init_task_tag);
+		return NULL;
+	}
+
+	if ((read_data_left <= conn->conn_ops->MaxRecvDataSegmentLength) &&
+	    (read_data_left <= (conn->sess->sess_ops->MaxBurstLength -
+	     next_burst_len))) {
+		datain->length = read_data_left;
+
+		datain->flags |= (ISCSI_FLAG_CMD_FINAL | ISCSI_FLAG_DATA_STATUS);
+		if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
+			datain->flags |= ISCSI_FLAG_DATA_ACK;
+	} else {
+		if ((next_burst_len +
+		     conn->conn_ops->MaxRecvDataSegmentLength) <
+		     conn->sess->sess_ops->MaxBurstLength) {
+			datain->length =
+				conn->conn_ops->MaxRecvDataSegmentLength;
+			next_burst_len += datain->length;
+		} else {
+			datain->length = (conn->sess->sess_ops->MaxBurstLength -
+					  next_burst_len);
+			next_burst_len = 0;
+
+			datain->flags |= ISCSI_FLAG_CMD_FINAL;
+			if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
+				datain->flags |= ISCSI_FLAG_DATA_ACK;
+		}
+	}
+
+	datain->data_sn = (!dr->recovery) ? cmd->data_sn++ : dr->data_sn++;
+	datain->offset = read_data_done;
+
+	if (!dr->recovery) {
+		cmd->next_burst_len = next_burst_len;
+		cmd->read_data_done += datain->length;
+	} else {
+		dr->next_burst_len = next_burst_len;
+		dr->read_data_done += datain->length;
+	}
+
+	if (!dr->recovery) {
+		if (datain->flags & ISCSI_FLAG_DATA_STATUS)
+			dr->dr_complete = DATAIN_COMPLETE_NORMAL;
+
+		return dr;
+	}
+
+	if (!dr->runlength) {
+		if (datain->flags & ISCSI_FLAG_DATA_STATUS) {
+			dr->dr_complete =
+			    (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
+				DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
+				DATAIN_COMPLETE_CONNECTION_RECOVERY;
+		}
+	} else {
+		if ((dr->begrun + dr->runlength) == dr->data_sn) {
+			dr->dr_complete =
+			    (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
+				DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
+				DATAIN_COMPLETE_CONNECTION_RECOVERY;
+		}
+	}
+
+	return dr;
+}
+
+/*
+ *	For Normal and Recovery DataSequenceInOrder=No and DataPDUInOrder=Yes.
+ */
+static struct iscsi_datain_req *iscsit_set_datain_values_no_and_yes(
+	struct iscsi_cmd *cmd,
+	struct iscsi_datain *datain)
+{
+	u32 offset, read_data_done, read_data_left, seq_send_order;
+	struct iscsi_conn *conn = cmd->conn;
+	struct iscsi_datain_req *dr;
+	struct iscsi_seq *seq;
+
+	dr = iscsit_get_datain_req(cmd);
+	if (!dr)
+		return NULL;
+
+	if (dr->recovery && dr->generate_recovery_values) {
+		if (iscsit_create_recovery_datain_values_datasequenceinorder_no(
+					cmd, dr) < 0)
+			return NULL;
+
+		dr->generate_recovery_values = 0;
+	}
+
+	read_data_done = (!dr->recovery) ?
+			cmd->read_data_done : dr->read_data_done;
+	seq_send_order = (!dr->recovery) ?
+			cmd->seq_send_order : dr->seq_send_order;
+
+	read_data_left = (cmd->data_length - read_data_done);
+	if (!read_data_left) {
+		pr_err("ITT: 0x%08x read_data_left is zero!\n",
+				cmd->init_task_tag);
+		return NULL;
+	}
+
+	seq = iscsit_get_seq_holder_for_datain(cmd, seq_send_order);
+	if (!seq)
+		return NULL;
+
+	seq->sent = 1;
+
+	if (!dr->recovery && !seq->next_burst_len)
+		seq->first_datasn = cmd->data_sn;
+
+	offset = (seq->offset + seq->next_burst_len);
+
+	if ((offset + conn->conn_ops->MaxRecvDataSegmentLength) >=
+	     cmd->data_length) {
+		datain->length = (cmd->data_length - offset);
+		datain->offset = offset;
+
+		datain->flags |= ISCSI_FLAG_CMD_FINAL;
+		if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
+			datain->flags |= ISCSI_FLAG_DATA_ACK;
+
+		seq->next_burst_len = 0;
+		seq_send_order++;
+	} else {
+		if ((seq->next_burst_len +
+		     conn->conn_ops->MaxRecvDataSegmentLength) <
+		     conn->sess->sess_ops->MaxBurstLength) {
+			datain->length =
+				conn->conn_ops->MaxRecvDataSegmentLength;
+			datain->offset = (seq->offset + seq->next_burst_len);
+
+			seq->next_burst_len += datain->length;
+		} else {
+			datain->length = (conn->sess->sess_ops->MaxBurstLength -
+					  seq->next_burst_len);
+			datain->offset = (seq->offset + seq->next_burst_len);
+
+			datain->flags |= ISCSI_FLAG_CMD_FINAL;
+			if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
+				datain->flags |= ISCSI_FLAG_DATA_ACK;
+
+			seq->next_burst_len = 0;
+			seq_send_order++;
+		}
+	}
+
+	if ((read_data_done + datain->length) == cmd->data_length)
+		datain->flags |= ISCSI_FLAG_DATA_STATUS;
+
+	datain->data_sn = (!dr->recovery) ? cmd->data_sn++ : dr->data_sn++;
+	if (!dr->recovery) {
+		cmd->seq_send_order = seq_send_order;
+		cmd->read_data_done += datain->length;
+	} else {
+		dr->seq_send_order = seq_send_order;
+		dr->read_data_done += datain->length;
+	}
+
+	if (!dr->recovery) {
+		if (datain->flags & ISCSI_FLAG_CMD_FINAL)
+			seq->last_datasn = datain->data_sn;
+		if (datain->flags & ISCSI_FLAG_DATA_STATUS)
+			dr->dr_complete = DATAIN_COMPLETE_NORMAL;
+
+		return dr;
+	}
+
+	if (!dr->runlength) {
+		if (datain->flags & ISCSI_FLAG_DATA_STATUS) {
+			dr->dr_complete =
+			    (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
+				DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
+				DATAIN_COMPLETE_CONNECTION_RECOVERY;
+		}
+	} else {
+		if ((dr->begrun + dr->runlength) == dr->data_sn) {
+			dr->dr_complete =
+			    (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
+				DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
+				DATAIN_COMPLETE_CONNECTION_RECOVERY;
+		}
+	}
+
+	return dr;
+}
+
+/*
+ *	For Normal and Recovery DataSequenceInOrder=Yes and DataPDUInOrder=No.
+ */
+static struct iscsi_datain_req *iscsit_set_datain_values_yes_and_no(
+	struct iscsi_cmd *cmd,
+	struct iscsi_datain *datain)
+{
+	u32 next_burst_len, read_data_done, read_data_left;
+	struct iscsi_conn *conn = cmd->conn;
+	struct iscsi_datain_req *dr;
+	struct iscsi_pdu *pdu;
+
+	dr = iscsit_get_datain_req(cmd);
+	if (!dr)
+		return NULL;
+
+	if (dr->recovery && dr->generate_recovery_values) {
+		if (iscsit_create_recovery_datain_values_datasequenceinorder_yes(
+					cmd, dr) < 0)
+			return NULL;
+
+		dr->generate_recovery_values = 0;
+	}
+
+	next_burst_len = (!dr->recovery) ?
+			cmd->next_burst_len : dr->next_burst_len;
+	read_data_done = (!dr->recovery) ?
+			cmd->read_data_done : dr->read_data_done;
+
+	read_data_left = (cmd->data_length - read_data_done);
+	if (!read_data_left) {
+		pr_err("ITT: 0x%08x read_data_left is zero!\n",
+				cmd->init_task_tag);
+		return dr;
+	}
+
+	pdu = iscsit_get_pdu_holder_for_seq(cmd, NULL);
+	if (!pdu)
+		return dr;
+
+	if ((read_data_done + pdu->length) == cmd->data_length) {
+		pdu->flags |= (ISCSI_FLAG_CMD_FINAL | ISCSI_FLAG_DATA_STATUS);
+		if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
+			pdu->flags |= ISCSI_FLAG_DATA_ACK;
+
+		next_burst_len = 0;
+	} else {
+		if ((next_burst_len + conn->conn_ops->MaxRecvDataSegmentLength) <
+		     conn->sess->sess_ops->MaxBurstLength)
+			next_burst_len += pdu->length;
+		else {
+			pdu->flags |= ISCSI_FLAG_CMD_FINAL;
+			if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
+				pdu->flags |= ISCSI_FLAG_DATA_ACK;
+
+			next_burst_len = 0;
+		}
+	}
+
+	pdu->data_sn = (!dr->recovery) ? cmd->data_sn++ : dr->data_sn++;
+	if (!dr->recovery) {
+		cmd->next_burst_len = next_burst_len;
+		cmd->read_data_done += pdu->length;
+	} else {
+		dr->next_burst_len = next_burst_len;
+		dr->read_data_done += pdu->length;
+	}
+
+	datain->flags = pdu->flags;
+	datain->length = pdu->length;
+	datain->offset = pdu->offset;
+	datain->data_sn = pdu->data_sn;
+
+	if (!dr->recovery) {
+		if (datain->flags & ISCSI_FLAG_DATA_STATUS)
+			dr->dr_complete = DATAIN_COMPLETE_NORMAL;
+
+		return dr;
+	}
+
+	if (!dr->runlength) {
+		if (datain->flags & ISCSI_FLAG_DATA_STATUS) {
+			dr->dr_complete =
+			    (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
+				DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
+				DATAIN_COMPLETE_CONNECTION_RECOVERY;
+		}
+	} else {
+		if ((dr->begrun + dr->runlength) == dr->data_sn) {
+			dr->dr_complete =
+			    (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
+				DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
+				DATAIN_COMPLETE_CONNECTION_RECOVERY;
+		}
+	}
+
+	return dr;
+}
+
+/*
+ *	For Normal and Recovery DataSequenceInOrder=No and DataPDUInOrder=No.
+ */
+static struct iscsi_datain_req *iscsit_set_datain_values_no_and_no(
+	struct iscsi_cmd *cmd,
+	struct iscsi_datain *datain)
+{
+	u32 read_data_done, read_data_left, seq_send_order;
+	struct iscsi_conn *conn = cmd->conn;
+	struct iscsi_datain_req *dr;
+	struct iscsi_pdu *pdu;
+	struct iscsi_seq *seq = NULL;
+
+	dr = iscsit_get_datain_req(cmd);
+	if (!dr)
+		return NULL;
+
+	if (dr->recovery && dr->generate_recovery_values) {
+		if (iscsit_create_recovery_datain_values_datasequenceinorder_no(
+					cmd, dr) < 0)
+			return NULL;
+
+		dr->generate_recovery_values = 0;
+	}
+
+	read_data_done = (!dr->recovery) ?
+			cmd->read_data_done : dr->read_data_done;
+	seq_send_order = (!dr->recovery) ?
+			cmd->seq_send_order : dr->seq_send_order;
+
+	read_data_left = (cmd->data_length - read_data_done);
+	if (!read_data_left) {
+		pr_err("ITT: 0x%08x read_data_left is zero!\n",
+				cmd->init_task_tag);
+		return NULL;
+	}
+
+	seq = iscsit_get_seq_holder_for_datain(cmd, seq_send_order);
+	if (!seq)
+		return NULL;
+
+	seq->sent = 1;
+
+	if (!dr->recovery && !seq->next_burst_len)
+		seq->first_datasn = cmd->data_sn;
+
+	pdu = iscsit_get_pdu_holder_for_seq(cmd, seq);
+	if (!pdu)
+		return NULL;
+
+	if (seq->pdu_send_order == seq->pdu_count) {
+		pdu->flags |= ISCSI_FLAG_CMD_FINAL;
+		if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
+			pdu->flags |= ISCSI_FLAG_DATA_ACK;
+
+		seq->next_burst_len = 0;
+		seq_send_order++;
+	} else
+		seq->next_burst_len += pdu->length;
+
+	if ((read_data_done + pdu->length) == cmd->data_length)
+		pdu->flags |= ISCSI_FLAG_DATA_STATUS;
+
+	pdu->data_sn = (!dr->recovery) ? cmd->data_sn++ : dr->data_sn++;
+	if (!dr->recovery) {
+		cmd->seq_send_order = seq_send_order;
+		cmd->read_data_done += pdu->length;
+	} else {
+		dr->seq_send_order = seq_send_order;
+		dr->read_data_done += pdu->length;
+	}
+
+	datain->flags = pdu->flags;
+	datain->length = pdu->length;
+	datain->offset = pdu->offset;
+	datain->data_sn = pdu->data_sn;
+
+	if (!dr->recovery) {
+		if (datain->flags & ISCSI_FLAG_CMD_FINAL)
+			seq->last_datasn = datain->data_sn;
+		if (datain->flags & ISCSI_FLAG_DATA_STATUS)
+			dr->dr_complete = DATAIN_COMPLETE_NORMAL;
+
+		return dr;
+	}
+
+	if (!dr->runlength) {
+		if (datain->flags & ISCSI_FLAG_DATA_STATUS) {
+			dr->dr_complete =
+			    (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
+				DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
+				DATAIN_COMPLETE_CONNECTION_RECOVERY;
+		}
+	} else {
+		if ((dr->begrun + dr->runlength) == dr->data_sn) {
+			dr->dr_complete =
+			    (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
+				DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
+				DATAIN_COMPLETE_CONNECTION_RECOVERY;
+		}
+	}
+
+	return dr;
+}
+
+struct iscsi_datain_req *iscsit_get_datain_values(
+	struct iscsi_cmd *cmd,
+	struct iscsi_datain *datain)
+{
+	struct iscsi_conn *conn = cmd->conn;
+
+	if (conn->sess->sess_ops->DataSequenceInOrder &&
+	    conn->sess->sess_ops->DataPDUInOrder)
+		return iscsit_set_datain_values_yes_and_yes(cmd, datain);
+	else if (!conn->sess->sess_ops->DataSequenceInOrder &&
+		  conn->sess->sess_ops->DataPDUInOrder)
+		return iscsit_set_datain_values_no_and_yes(cmd, datain);
+	else if (conn->sess->sess_ops->DataSequenceInOrder &&
+		 !conn->sess->sess_ops->DataPDUInOrder)
+		return iscsit_set_datain_values_yes_and_no(cmd, datain);
+	else if (!conn->sess->sess_ops->DataSequenceInOrder &&
+		   !conn->sess->sess_ops->DataPDUInOrder)
+		return iscsit_set_datain_values_no_and_no(cmd, datain);
+
+	return NULL;
+}