/*******************************************************************************
* This file contains the iSCSI Target specific Task Management 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 <asm/unaligned.h>
#include <scsi/scsi_device.h>
#include <scsi/iscsi_proto.h>
#include <target/target_core_base.h>
#include <target/target_core_fabric.h>
#include <target/iscsi/iscsi_transport.h>
#include "iscsi_target_core.h"
#include "iscsi_target_seq_pdu_list.h"
#include "iscsi_target_datain_values.h"
#include "iscsi_target_device.h"
#include "iscsi_target_erl0.h"
#include "iscsi_target_erl1.h"
#include "iscsi_target_erl2.h"
#include "iscsi_target_tmr.h"
#include "iscsi_target_tpg.h"
#include "iscsi_target_util.h"
#include "iscsi_target.h"
u8 iscsit_tmr_abort_task(
struct iscsi_cmd *cmd,
unsigned char *buf)
{
struct iscsi_cmd *ref_cmd;
struct iscsi_conn *conn = cmd->conn;
struct iscsi_tmr_req *tmr_req = cmd->tmr_req;
struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
struct iscsi_tm *hdr = (struct iscsi_tm *) buf;
ref_cmd = iscsit_find_cmd_from_itt(conn, hdr->rtt);
if (!ref_cmd) {
pr_err("Unable to locate RefTaskTag: 0x%08x on CID:"
" %hu.\n", hdr->rtt, conn->cid);
return (iscsi_sna_gte(be32_to_cpu(hdr->refcmdsn), conn->sess->exp_cmd_sn) &&
iscsi_sna_lte(be32_to_cpu(hdr->refcmdsn), conn->sess->max_cmd_sn)) ?
ISCSI_TMF_RSP_COMPLETE : ISCSI_TMF_RSP_NO_TASK;
}
if (ref_cmd->cmd_sn != be32_to_cpu(hdr->refcmdsn)) {
pr_err("RefCmdSN 0x%08x does not equal"
" task's CmdSN 0x%08x. Rejecting ABORT_TASK.\n",
hdr->refcmdsn, ref_cmd->cmd_sn);
return ISCSI_TMF_RSP_REJECTED;
}
se_tmr->ref_task_tag = (__force u32)hdr->rtt;
tmr_req->ref_cmd = ref_cmd;
tmr_req->exp_data_sn = be32_to_cpu(hdr->exp_datasn);
return ISCSI_TMF_RSP_COMPLETE;
}
/*
* Called from iscsit_handle_task_mgt_cmd().
*/
int iscsit_tmr_task_warm_reset(
struct iscsi_conn *conn,
struct iscsi_tmr_req *tmr_req,
unsigned char *buf)
{
struct iscsi_session *sess = conn->sess;
struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
if (!na->tmr_warm_reset) {
pr_err("TMR Opcode TARGET_WARM_RESET authorization"
" failed for Initiator Node: %s\n",
sess->se_sess->se_node_acl->initiatorname);
return -1;
}
/*
* Do the real work in transport_generic_do_tmr().
*/
return 0;
}
int iscsit_tmr_task_cold_reset(
struct iscsi_conn *conn,
struct iscsi_tmr_req *tmr_req,
unsigned char *buf)
{
struct iscsi_session *sess = conn->sess;
struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
if (!na->tmr_cold_reset) {
pr_err("TMR Opcode TARGET_COLD_RESET authorization"
" failed for Initiator Node: %s\n",
sess->se_sess->se_node_acl->initiatorname);
return -1;
}
/*
* Do the real work in transport_generic_do_tmr().
*/
return 0;
}
u8 iscsit_tmr_task_reassign(
struct iscsi_cmd *cmd,
unsigned char *buf)
{
struct iscsi_cmd *ref_cmd = NULL;
struct iscsi_conn *conn = cmd->conn;
struct iscsi_conn_recovery *cr = NULL;
struct iscsi_tmr_req *tmr_req = cmd->tmr_req;
struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
struct iscsi_tm *hdr = (struct iscsi_tm *) buf;
int ret, ref_lun;
pr_debug("Got TASK_REASSIGN TMR ITT: 0x%08x,"
" RefTaskTag: 0x%08x, ExpDataSN: 0x%08x, CID: %hu\n",
hdr->itt, hdr->rtt, hdr->exp_datasn, conn->cid);
if (conn->sess->sess_ops->ErrorRecoveryLevel != 2) {
pr_err("TMR TASK_REASSIGN not supported in ERL<2,"
" ignoring request.\n");
return ISCSI_TMF_RSP_NOT_SUPPORTED;
}
ret = iscsit_find_cmd_for_recovery(conn->sess, &ref_cmd, &cr, hdr->rtt);
if (ret == -2) {
pr_err("Command ITT: 0x%08x is still alligent to CID:"
" %hu\n", ref_cmd->init_task_tag, cr->cid);
return ISCSI_TMF_RSP_TASK_ALLEGIANT;
} else if (ret == -1) {
pr_err("Unable to locate RefTaskTag: 0x%08x in"
" connection recovery command list.\n", hdr->rtt);
return ISCSI_TMF_RSP_NO_TASK;
}
/*
* Temporary check to prevent connection recovery for
* connections with a differing Max*DataSegmentLength.
*/
if (cr->maxrecvdatasegmentlength !=
conn->conn_ops->MaxRecvDataSegmentLength) {
pr_err("Unable to perform connection recovery for"
" differing MaxRecvDataSegmentLength, rejecting"
" TMR TASK_REASSIGN.\n");
return ISCSI_TMF_RSP_REJECTED;
}
if (cr->maxxmitdatasegmentlength !=
conn->conn_ops->MaxXmitDataSegmentLength) {
pr_err("Unable to perform connection recovery for"
" differing MaxXmitDataSegmentLength, rejecting"
" TMR TASK_REASSIGN.\n");
return ISCSI_TMF_RSP_REJECTED;
}
ref_lun = scsilun_to_int(&hdr->lun);
if (ref_lun != ref_cmd->se_cmd.orig_fe_lun) {
pr_err("Unable to perform connection recovery for"
" differing ref_lun: %d ref_cmd orig_fe_lun: %u\n",
ref_lun, ref_cmd->se_cmd.orig_fe_lun);
return ISCSI_TMF_RSP_REJECTED;
}
se_tmr->ref_task_tag = (__force u32)hdr->rtt;
tmr_req->ref_cmd = ref_cmd;
tmr_req->exp_data_sn = be32_to_cpu(hdr->exp_datasn);
tmr_req->conn_recovery = cr;
tmr_req->task_reassign = 1;
/*
* Command can now be reassigned to a new connection.
* The task management response must be sent before the
* reassignment actually happens. See iscsi_tmr_post_handler().
*/
return ISCSI_TMF_RSP_COMPLETE;
}
static void iscsit_task_reassign_remove_cmd(
struct iscsi_cmd *cmd,
struct iscsi_conn_recovery *cr,
struct iscsi_session *sess)
{
int ret;
spin_lock(&cr->conn_recovery_cmd_lock);
ret = iscsit_remove_cmd_from_connection_recovery(cmd, sess);
spin_unlock(&cr->conn_recovery_cmd_lock);
if (!ret) {
pr_debug("iSCSI connection recovery successful for CID:"
" %hu on SID: %u\n", cr->cid, sess->sid);
iscsit_remove_active_connection_recovery_entry(cr, sess);
}
}
static int iscsit_task_reassign_complete_nop_out(
struct iscsi_tmr_req *tmr_req,
struct iscsi_conn *conn)
{
struct iscsi_cmd *cmd = tmr_req->ref_cmd;
struct iscsi_conn_recovery *cr;
if (!cmd->cr) {
pr_err("struct iscsi_conn_recovery pointer for ITT: 0x%08x"
" is NULL!\n", cmd->init_task_tag);
return -1;
}
cr = cmd->cr;
/*
* Reset the StatSN so a new one for this commands new connection
* will be assigned.
* Reset the ExpStatSN as well so we may receive Status SNACKs.
*/
cmd->stat_sn = cmd->exp_stat_sn = 0;
iscsit_task_reassign_remove_cmd(cmd, cr, conn->sess);
spin_lock_bh(&conn->cmd_lock);
list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
spin_unlock_bh(&conn->cmd_lock);
cmd->i_state = ISTATE_SEND_NOPIN;
iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
return 0;
}
static int iscsit_task_reassign_complete_write(
struct iscsi_cmd *cmd,
struct iscsi_tmr_req *tmr_req)
{
int no_build_r2ts = 0;
u32 length = 0, offset = 0;
struct iscsi_conn *conn = cmd->conn;
struct se_cmd *se_cmd = &cmd->se_cmd;
/*
* The Initiator must not send a R2T SNACK with a Begrun less than
* the TMR TASK_REASSIGN's ExpDataSN.
*/
if (!tmr_req->exp_data_sn) {
cmd->cmd_flags &= ~ICF_GOT_DATACK_SNACK;
cmd->acked_data_sn = 0;
} else {
cmd->cmd_flags |= ICF_GOT_DATACK_SNACK;
cmd->acked_data_sn = (tmr_req->exp_data_sn - 1);
}
/*
* The TMR TASK_REASSIGN's ExpDataSN contains the next R2TSN the
* Initiator is expecting. The Target controls all WRITE operations
* so if we have received all DataOUT we can safety ignore Initiator.
*/
if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
if (!(cmd->se_cmd.transport_state & CMD_T_SENT)) {
pr_debug("WRITE ITT: 0x%08x: t_state: %d"
" never sent to transport\n",
cmd->init_task_tag, cmd->se_cmd.t_state);
target_execute_cmd(se_cmd);
return 0;
}
cmd->i_state = ISTATE_SEND_STATUS;
iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
return 0;
}
/*
* Special case to deal with DataSequenceInOrder=No and Non-Immeidate
* Unsolicited DataOut.
*/
if (cmd->unsolicited_data) {
cmd->unsolicited_data = 0;
offset = cmd->next_burst_len = cmd->write_data_done;
if ((conn->sess->sess_ops->FirstBurstLength - offset) >=
cmd->se_cmd.data_length) {
no_build_r2ts = 1;
length = (cmd->se_cmd.data_length - offset);
} else
length = (conn->sess->sess_ops->FirstBurstLength - offset);
spin_lock_bh(&cmd->r2t_lock);
if (iscsit_add_r2t_to_list(cmd, offset, length, 0, 0) < 0) {
spin_unlock_bh(&cmd->r2t_lock);
return -1;
}
cmd->outstanding_r2ts++;
spin_unlock_bh(&cmd->r2t_lock);
if (no_build_r2ts)
return 0;
}
/*
* iscsit_build_r2ts_for_cmd() can handle the rest from here.
*/
return conn->conn_transport->iscsit_get_dataout(conn, cmd, true);
}
static int iscsit_task_reassign_complete_read(
struct iscsi_cmd *cmd,
struct iscsi_tmr_req *tmr_req)
{
struct iscsi_conn *conn = cmd->conn;
struct iscsi_datain_req *dr;
struct se_cmd *se_cmd = &cmd->se_cmd;
/*
* The Initiator must not send a Data SNACK with a BegRun less than
* the TMR TASK_REASSIGN's ExpDataSN.
*/
if (!tmr_req->exp_data_sn) {
cmd->cmd_flags &= ~ICF_GOT_DATACK_SNACK;
cmd->acked_data_sn = 0;
} else {
cmd->cmd_flags |= ICF_GOT_DATACK_SNACK;
cmd->acked_data_sn = (tmr_req->exp_data_sn - 1);
}
if (!(cmd->se_cmd.transport_state & CMD_T_SENT)) {
pr_debug("READ ITT: 0x%08x: t_state: %d never sent to"
" transport\n", cmd->init_task_tag,
cmd->se_cmd.t_state);
transport_handle_cdb_direct(se_cmd);
return 0;
}
if (!(se_cmd->transport_state & CMD_T_COMPLETE)) {
pr_err("READ ITT: 0x%08x: t_state: %d, never returned"
" from transport\n", cmd->init_task_tag,
cmd->se_cmd.t_state);
return -1;
}
dr = iscsit_allocate_datain_req();
if (!dr)
return -1;
/*
* The TMR TASK_REASSIGN's ExpDataSN contains the next DataSN the
* Initiator is expecting.
*/
dr->data_sn = dr->begrun = tmr_req->exp_data_sn;
dr->runlength = 0;
dr->generate_recovery_values = 1;
dr->recovery = DATAIN_CONNECTION_RECOVERY;
iscsit_attach_datain_req(cmd, dr);
cmd->i_state = ISTATE_SEND_DATAIN;
iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
return 0;
}
static int iscsit_task_reassign_complete_none(
struct iscsi_cmd *cmd,
struct iscsi_tmr_req *tmr_req)
{
struct iscsi_conn *conn = cmd->conn;
cmd->i_state = ISTATE_SEND_STATUS;
iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
return 0;
}
static int iscsit_task_reassign_complete_scsi_cmnd(
struct iscsi_tmr_req *tmr_req,
struct iscsi_conn *conn)
{
struct iscsi_cmd *cmd = tmr_req->ref_cmd;
struct iscsi_conn_recovery *cr;
if (!cmd->cr) {
pr_err("struct iscsi_conn_recovery pointer for ITT: 0x%08x"
" is NULL!\n", cmd->init_task_tag);
return -1;
}
cr = cmd->cr;
/*
* Reset the StatSN so a new one for this commands new connection
* will be assigned.
* Reset the ExpStatSN as well so we may receive Status SNACKs.
*/
cmd->stat_sn = cmd->exp_stat_sn = 0;
iscsit_task_reassign_remove_cmd(cmd, cr, conn->sess);
spin_lock_bh(&conn->cmd_lock);
list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
spin_unlock_bh(&conn->cmd_lock);
if (cmd->se_cmd.se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
cmd->i_state = ISTATE_SEND_STATUS;
iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
return 0;
}
switch (cmd->data_direction) {
case DMA_TO_DEVICE:
return iscsit_task_reassign_complete_write(cmd, tmr_req);
case DMA_FROM_DEVICE:
return iscsit_task_reassign_complete_read(cmd, tmr_req);
case DMA_NONE:
return iscsit_task_reassign_complete_none(cmd, tmr_req);
default:
pr_err("Unknown cmd->data_direction: 0x%02x\n",
cmd->data_direction);
return -1;
}
return 0;
}
static int iscsit_task_reassign_complete(
struct iscsi_tmr_req *tmr_req,
struct iscsi_conn *conn)
{
struct iscsi_cmd *cmd;
int ret = 0;
if (!tmr_req->ref_cmd) {
pr_err("TMR Request is missing a RefCmd struct iscsi_cmd.\n");
return -1;
}
cmd = tmr_req->ref_cmd;
cmd->conn = conn;
switch (cmd->iscsi_opcode) {
case ISCSI_OP_NOOP_OUT:
ret = iscsit_task_reassign_complete_nop_out(tmr_req, conn);
break;
case ISCSI_OP_SCSI_CMD:
ret = iscsit_task_reassign_complete_scsi_cmnd(tmr_req, conn);
break;
default:
pr_err("Illegal iSCSI Opcode 0x%02x during"
" command realligence\n", cmd->iscsi_opcode);
return -1;
}
if (ret != 0)
return ret;
pr_debug("Completed connection realligence for Opcode: 0x%02x,"
" ITT: 0x%08x to CID: %hu.\n", cmd->iscsi_opcode,
cmd->init_task_tag, conn->cid);
return 0;
}
/*
* Handles special after-the-fact actions related to TMRs.
* Right now the only one that its really needed for is
* connection recovery releated TASK_REASSIGN.
*/
int iscsit_tmr_post_handler(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
{
struct iscsi_tmr_req *tmr_req = cmd->tmr_req;
struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
if (tmr_req->task_reassign &&
(se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
return iscsit_task_reassign_complete(tmr_req, conn);
return 0;
}
EXPORT_SYMBOL(iscsit_tmr_post_handler);
/*
* Nothing to do here, but leave it for good measure. :-)
*/
static int iscsit_task_reassign_prepare_read(
struct iscsi_tmr_req *tmr_req,
struct iscsi_conn *conn)
{
return 0;
}
static void iscsit_task_reassign_prepare_unsolicited_dataout(
struct iscsi_cmd *cmd,
struct iscsi_conn *conn)
{
int i, j;
struct iscsi_pdu *pdu = NULL;
struct iscsi_seq *seq = NULL;
if (conn->sess->sess_ops->DataSequenceInOrder) {
cmd->data_sn = 0;
if (cmd->immediate_data)
cmd->r2t_offset += (cmd->first_burst_len -
cmd->seq_start_offset);
if (conn->sess->sess_ops->DataPDUInOrder) {
cmd->write_data_done -= (cmd->immediate_data) ?
(cmd->first_burst_len -
cmd->seq_start_offset) :
cmd->first_burst_len;
cmd->first_burst_len = 0;
return;
}
for (i = 0; i < cmd->pdu_count; i++) {
pdu = &cmd->pdu_list[i];
if (pdu->status != ISCSI_PDU_RECEIVED_OK)
continue;
if ((pdu->offset >= cmd->seq_start_offset) &&
((pdu->offset + pdu->length) <=
cmd->seq_end_offset)) {
cmd->first_burst_len -= pdu->length;
cmd->write_data_done -= pdu->length;
pdu->status = ISCSI_PDU_NOT_RECEIVED;
}
}
} else {
for (i = 0; i < cmd->seq_count; i++) {
seq = &cmd->seq_list[i];
if (seq->type != SEQTYPE_UNSOLICITED)
continue;
cmd->write_data_done -=
(seq->offset - seq->orig_offset);
cmd->first_burst_len = 0;
seq->data_sn = 0;
seq->offset = seq->orig_offset;
seq->next_burst_len = 0;
seq->status = DATAOUT_SEQUENCE_WITHIN_COMMAND_RECOVERY;
if (conn->sess->sess_ops->DataPDUInOrder)
continue;
for (j = 0; j < seq->pdu_count; j++) {
pdu = &cmd->pdu_list[j+seq->pdu_start];
if (pdu->status != ISCSI_PDU_RECEIVED_OK)
continue;
pdu->status = ISCSI_PDU_NOT_RECEIVED;
}
}
}
}
static int iscsit_task_reassign_prepare_write(
struct iscsi_tmr_req *tmr_req,
struct iscsi_conn *conn)
{
struct iscsi_cmd *cmd = tmr_req->ref_cmd;
struct iscsi_pdu *pdu = NULL;
struct iscsi_r2t *r2t = NULL, *r2t_tmp;
int first_incomplete_r2t = 1, i = 0;
/*
* The command was in the process of receiving Unsolicited DataOUT when
* the connection failed.
*/
if (cmd->unsolicited_data)
iscsit_task_reassign_prepare_unsolicited_dataout(cmd, conn);
/*
* The Initiator is requesting R2Ts starting from zero, skip
* checking acknowledged R2Ts and start checking struct iscsi_r2ts
* greater than zero.
*/
if (!tmr_req->exp_data_sn)
goto drop_unacknowledged_r2ts;
/*
* We now check that the PDUs in DataOUT sequences below
* the TMR TASK_REASSIGN ExpDataSN (R2TSN the Initiator is
* expecting next) have all the DataOUT they require to complete
* the DataOUT sequence. First scan from R2TSN 0 to TMR
* TASK_REASSIGN ExpDataSN-1.
*
* If we have not received all DataOUT in question, we must
* make sure to make the appropriate changes to values in
* struct iscsi_cmd (and elsewhere depending on session parameters)
* so iscsit_build_r2ts_for_cmd() in iscsit_task_reassign_complete_write()
* will resend a new R2T for the DataOUT sequences in question.
*/
spin_lock_bh(&cmd->r2t_lock);
if (list_empty(&cmd->cmd_r2t_list)) {
spin_unlock_bh(&cmd->r2t_lock);
return -1;
}
list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
if (r2t->r2t_sn >= tmr_req->exp_data_sn)
continue;
/*
* Safely ignore Recovery R2Ts and R2Ts that have completed
* DataOUT sequences.
*/
if (r2t->seq_complete)
continue;
if (r2t->recovery_r2t)
continue;
/*
* DataSequenceInOrder=Yes:
*
* Taking into account the iSCSI implementation requirement of
* MaxOutstandingR2T=1 while ErrorRecoveryLevel>0 and
* DataSequenceInOrder=Yes, we must take into consideration
* the following:
*
* DataSequenceInOrder=No:
*
* Taking into account that the Initiator controls the (possibly
* random) PDU Order in (possibly random) Sequence Order of
* DataOUT the target requests with R2Ts, we must take into
* consideration the following:
*
* DataPDUInOrder=Yes for DataSequenceInOrder=[Yes,No]:
*
* While processing non-complete R2T DataOUT sequence requests
* the Target will re-request only the total sequence length
* minus current received offset. This is because we must
* assume the initiator will continue sending DataOUT from the
* last PDU before the connection failed.
*
* DataPDUInOrder=No for DataSequenceInOrder=[Yes,No]:
*
* While processing non-complete R2T DataOUT sequence requests
* the Target will re-request the entire DataOUT sequence if
* any single PDU is missing from the sequence. This is because
* we have no logical method to determine the next PDU offset,
* and we must assume the Initiator will be sending any random
* PDU offset in the current sequence after TASK_REASSIGN
* has completed.
*/
if (conn->sess->sess_ops->DataSequenceInOrder) {
if (!first_incomplete_r2t) {
cmd->r2t_offset -= r2t->xfer_len;
goto next;
}
if (conn->sess->sess_ops->DataPDUInOrder) {
cmd->data_sn = 0;
cmd->r2t_offset -= (r2t->xfer_len -
cmd->next_burst_len);
first_incomplete_r2t = 0;
goto next;
}
cmd->data_sn = 0;
cmd->r2t_offset -= r2t->xfer_len;
for (i = 0; i < cmd->pdu_count; i++) {
pdu = &cmd->pdu_list[i];
if (pdu->status != ISCSI_PDU_RECEIVED_OK)
continue;
if ((pdu->offset >= r2t->offset) &&
(pdu->offset < (r2t->offset +
r2t->xfer_len))) {
cmd->next_burst_len -= pdu->length;
cmd->write_data_done -= pdu->length;
pdu->status = ISCSI_PDU_NOT_RECEIVED;
}
}
first_incomplete_r2t = 0;
} else {
struct iscsi_seq *seq;
seq = iscsit_get_seq_holder(cmd, r2t->offset,
r2t->xfer_len);
if (!seq) {
spin_unlock_bh(&cmd->r2t_lock);
return -1;
}
cmd->write_data_done -=
(seq->offset - seq->orig_offset);
seq->data_sn = 0;
seq->offset = seq->orig_offset;
seq->next_burst_len = 0;
seq->status = DATAOUT_SEQUENCE_WITHIN_COMMAND_RECOVERY;
cmd->seq_send_order--;
if (conn->sess->sess_ops->DataPDUInOrder)
goto next;
for (i = 0; i < seq->pdu_count; i++) {
pdu = &cmd->pdu_list[i+seq->pdu_start];
if (pdu->status != ISCSI_PDU_RECEIVED_OK)
continue;
pdu->status = ISCSI_PDU_NOT_RECEIVED;
}
}
next:
cmd->outstanding_r2ts--;
}
spin_unlock_bh(&cmd->r2t_lock);
/*
* We now drop all unacknowledged R2Ts, ie: ExpDataSN from TMR
* TASK_REASSIGN to the last R2T in the list.. We are also careful
* to check that the Initiator is not requesting R2Ts for DataOUT
* sequences it has already completed.
*
* Free each R2T in question and adjust values in struct iscsi_cmd
* accordingly so iscsit_build_r2ts_for_cmd() do the rest of
* the work after the TMR TASK_REASSIGN Response is sent.
*/
drop_unacknowledged_r2ts:
cmd->cmd_flags &= ~ICF_SENT_LAST_R2T;
cmd->r2t_sn = tmr_req->exp_data_sn;
spin_lock_bh(&cmd->r2t_lock);
list_for_each_entry_safe(r2t, r2t_tmp, &cmd->cmd_r2t_list, r2t_list) {
/*
* Skip up to the R2T Sequence number provided by the
* iSCSI TASK_REASSIGN TMR
*/
if (r2t->r2t_sn < tmr_req->exp_data_sn)
continue;
if (r2t->seq_complete) {
pr_err("Initiator is requesting R2Ts from"
" R2TSN: 0x%08x, but R2TSN: 0x%08x, Offset: %u,"
" Length: %u is already complete."
" BAD INITIATOR ERL=2 IMPLEMENTATION!\n",
tmr_req->exp_data_sn, r2t->r2t_sn,
r2t->offset, r2t->xfer_len);
spin_unlock_bh(&cmd->r2t_lock);
return -1;
}
if (r2t->recovery_r2t) {
iscsit_free_r2t(r2t, cmd);
continue;
}
/* DataSequenceInOrder=Yes:
*
* Taking into account the iSCSI implementation requirement of
* MaxOutstandingR2T=1 while ErrorRecoveryLevel>0 and
* DataSequenceInOrder=Yes, it's safe to subtract the R2Ts
* entire transfer length from the commands R2T offset marker.
*
* DataSequenceInOrder=No:
*
* We subtract the difference from struct iscsi_seq between the
* current offset and original offset from cmd->write_data_done
* for account for DataOUT PDUs already received. Then reset
* the current offset to the original and zero out the current
* burst length, to make sure we re-request the entire DataOUT
* sequence.
*/
if (conn->sess->sess_ops->DataSequenceInOrder)
cmd->r2t_offset -= r2t->xfer_len;
else
cmd->seq_send_order--;
cmd->outstanding_r2ts--;
iscsit_free_r2t(r2t, cmd);
}
spin_unlock_bh(&cmd->r2t_lock);
return 0;
}
/*
* Performs sanity checks TMR TASK_REASSIGN's ExpDataSN for
* a given struct iscsi_cmd.
*/
int iscsit_check_task_reassign_expdatasn(
struct iscsi_tmr_req *tmr_req,
struct iscsi_conn *conn)
{
struct iscsi_cmd *ref_cmd = tmr_req->ref_cmd;
if (ref_cmd->iscsi_opcode != ISCSI_OP_SCSI_CMD)
return 0;
if (ref_cmd->se_cmd.se_cmd_flags & SCF_SENT_CHECK_CONDITION)
return 0;
if (ref_cmd->data_direction == DMA_NONE)
return 0;
/*
* For READs the TMR TASK_REASSIGNs ExpDataSN contains the next DataSN
* of DataIN the Initiator is expecting.
*
* Also check that the Initiator is not re-requesting DataIN that has
* already been acknowledged with a DataAck SNACK.
*/
if (ref_cmd->data_direction == DMA_FROM_DEVICE) {
if (tmr_req->exp_data_sn > ref_cmd->data_sn) {
pr_err("Received ExpDataSN: 0x%08x for READ"
" in TMR TASK_REASSIGN greater than command's"
" DataSN: 0x%08x.\n", tmr_req->exp_data_sn,
ref_cmd->data_sn);
return -1;
}
if ((ref_cmd->cmd_flags & ICF_GOT_DATACK_SNACK) &&
(tmr_req->exp_data_sn <= ref_cmd->acked_data_sn)) {
pr_err("Received ExpDataSN: 0x%08x for READ"
" in TMR TASK_REASSIGN for previously"
" acknowledged DataIN: 0x%08x,"
" protocol error\n", tmr_req->exp_data_sn,
ref_cmd->acked_data_sn);
return -1;
}
return iscsit_task_reassign_prepare_read(tmr_req, conn);
}
/*
* For WRITEs the TMR TASK_REASSIGNs ExpDataSN contains the next R2TSN
* for R2Ts the Initiator is expecting.
*
* Do the magic in iscsit_task_reassign_prepare_write().
*/
if (ref_cmd->data_direction == DMA_TO_DEVICE) {
if (tmr_req->exp_data_sn > ref_cmd->r2t_sn) {
pr_err("Received ExpDataSN: 0x%08x for WRITE"
" in TMR TASK_REASSIGN greater than command's"
" R2TSN: 0x%08x.\n", tmr_req->exp_data_sn,
ref_cmd->r2t_sn);
return -1;
}
return iscsit_task_reassign_prepare_write(tmr_req, conn);
}
pr_err("Unknown iSCSI data_direction: 0x%02x\n",
ref_cmd->data_direction);
return -1;
}