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linux/drivers/scsi/libiscsi.c
Mike Christie 92ed4d6993 [SCSI] libiscsi: reset cmd timer if cmds are making progress 
This patch resets the cmd timer if cmds started before
the timedout command are making progress. The idea is
that the cmd probably timed out because we are trying
to exeucte too many commands. If it turns out that the
device the IO timedout on was bad or the cmd just got
screwed up but other IO/devs were ok then we will
will figure this out when the cmds ahead of the timed
out one complete ok.

This also fixes a bug where we were sort of detecting
this by setting the last_timeout and last_xfer to the
same value when the task was allocated. That caught
the case where we never got to send any IO for it. However,
if the problem had started right before we started the
new task, then we were forced to wait an extra cmd
timeout seconds to start the scsi eh.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-02-17 13:40:10 -06:00

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/*
* iSCSI lib functions
*
* Copyright (C) 2006 Red Hat, Inc. All rights reserved.
* Copyright (C) 2004 - 2006 Mike Christie
* Copyright (C) 2004 - 2005 Dmitry Yusupov
* Copyright (C) 2004 - 2005 Alex Aizman
* maintained by open-iscsi@googlegroups.com
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <linux/types.h>
#include <linux/kfifo.h>
#include <linux/delay.h>
#include <linux/log2.h>
#include <asm/unaligned.h>
#include <net/tcp.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_tcq.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi.h>
#include <scsi/iscsi_proto.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_iscsi.h>
#include <scsi/libiscsi.h>
static int iscsi_dbg_lib_conn;
module_param_named(debug_libiscsi_conn, iscsi_dbg_lib_conn, int,
S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug_libiscsi_conn,
"Turn on debugging for connections in libiscsi module. "
"Set to 1 to turn on, and zero to turn off. Default is off.");
static int iscsi_dbg_lib_session;
module_param_named(debug_libiscsi_session, iscsi_dbg_lib_session, int,
S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug_libiscsi_session,
"Turn on debugging for sessions in libiscsi module. "
"Set to 1 to turn on, and zero to turn off. Default is off.");
static int iscsi_dbg_lib_eh;
module_param_named(debug_libiscsi_eh, iscsi_dbg_lib_eh, int,
S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug_libiscsi_eh,
"Turn on debugging for error handling in libiscsi module. "
"Set to 1 to turn on, and zero to turn off. Default is off.");
#define ISCSI_DBG_CONN(_conn, dbg_fmt, arg...) \
do { \
if (iscsi_dbg_lib_conn) \
iscsi_conn_printk(KERN_INFO, _conn, \
"%s " dbg_fmt, \
__func__, ##arg); \
} while (0);
#define ISCSI_DBG_SESSION(_session, dbg_fmt, arg...) \
do { \
if (iscsi_dbg_lib_session) \
iscsi_session_printk(KERN_INFO, _session, \
"%s " dbg_fmt, \
__func__, ##arg); \
} while (0);
#define ISCSI_DBG_EH(_session, dbg_fmt, arg...) \
do { \
if (iscsi_dbg_lib_eh) \
iscsi_session_printk(KERN_INFO, _session, \
"%s " dbg_fmt, \
__func__, ##arg); \
} while (0);
/* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
#define SNA32_CHECK 2147483648UL
static int iscsi_sna_lt(u32 n1, u32 n2)
{
return n1 != n2 && ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
(n1 > n2 && (n2 - n1 < SNA32_CHECK)));
}
/* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
static int iscsi_sna_lte(u32 n1, u32 n2)
{
return n1 == n2 || ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
(n1 > n2 && (n2 - n1 < SNA32_CHECK)));
}
inline void iscsi_conn_queue_work(struct iscsi_conn *conn)
{
struct Scsi_Host *shost = conn->session->host;
struct iscsi_host *ihost = shost_priv(shost);
if (ihost->workq)
queue_work(ihost->workq, &conn->xmitwork);
}
EXPORT_SYMBOL_GPL(iscsi_conn_queue_work);
static void __iscsi_update_cmdsn(struct iscsi_session *session,
uint32_t exp_cmdsn, uint32_t max_cmdsn)
{
/*
* standard specifies this check for when to update expected and
* max sequence numbers
*/
if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
return;
if (exp_cmdsn != session->exp_cmdsn &&
!iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
session->exp_cmdsn = exp_cmdsn;
if (max_cmdsn != session->max_cmdsn &&
!iscsi_sna_lt(max_cmdsn, session->max_cmdsn)) {
session->max_cmdsn = max_cmdsn;
/*
* if the window closed with IO queued, then kick the
* xmit thread
*/
if (!list_empty(&session->leadconn->cmdqueue) ||
!list_empty(&session->leadconn->mgmtqueue))
iscsi_conn_queue_work(session->leadconn);
}
}
void iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
{
__iscsi_update_cmdsn(session, be32_to_cpu(hdr->exp_cmdsn),
be32_to_cpu(hdr->max_cmdsn));
}
EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
/**
* iscsi_prep_data_out_pdu - initialize Data-Out
* @task: scsi command task
* @r2t: R2T info
* @hdr: iscsi data in pdu
*
* Notes:
* Initialize Data-Out within this R2T sequence and finds
* proper data_offset within this SCSI command.
*
* This function is called with connection lock taken.
**/
void iscsi_prep_data_out_pdu(struct iscsi_task *task, struct iscsi_r2t_info *r2t,
struct iscsi_data *hdr)
{
struct iscsi_conn *conn = task->conn;
unsigned int left = r2t->data_length - r2t->sent;
task->hdr_len = sizeof(struct iscsi_data);
memset(hdr, 0, sizeof(struct iscsi_data));
hdr->ttt = r2t->ttt;
hdr->datasn = cpu_to_be32(r2t->datasn);
r2t->datasn++;
hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
memcpy(hdr->lun, task->lun, sizeof(hdr->lun));
hdr->itt = task->hdr_itt;
hdr->exp_statsn = r2t->exp_statsn;
hdr->offset = cpu_to_be32(r2t->data_offset + r2t->sent);
if (left > conn->max_xmit_dlength) {
hton24(hdr->dlength, conn->max_xmit_dlength);
r2t->data_count = conn->max_xmit_dlength;
hdr->flags = 0;
} else {
hton24(hdr->dlength, left);
r2t->data_count = left;
hdr->flags = ISCSI_FLAG_CMD_FINAL;
}
conn->dataout_pdus_cnt++;
}
EXPORT_SYMBOL_GPL(iscsi_prep_data_out_pdu);
static int iscsi_add_hdr(struct iscsi_task *task, unsigned len)
{
unsigned exp_len = task->hdr_len + len;
if (exp_len > task->hdr_max) {
WARN_ON(1);
return -EINVAL;
}
WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
task->hdr_len = exp_len;
return 0;
}
/*
* make an extended cdb AHS
*/
static int iscsi_prep_ecdb_ahs(struct iscsi_task *task)
{
struct scsi_cmnd *cmd = task->sc;
unsigned rlen, pad_len;
unsigned short ahslength;
struct iscsi_ecdb_ahdr *ecdb_ahdr;
int rc;
ecdb_ahdr = iscsi_next_hdr(task);
rlen = cmd->cmd_len - ISCSI_CDB_SIZE;
BUG_ON(rlen > sizeof(ecdb_ahdr->ecdb));
ahslength = rlen + sizeof(ecdb_ahdr->reserved);
pad_len = iscsi_padding(rlen);
rc = iscsi_add_hdr(task, sizeof(ecdb_ahdr->ahslength) +
sizeof(ecdb_ahdr->ahstype) + ahslength + pad_len);
if (rc)
return rc;
if (pad_len)
memset(&ecdb_ahdr->ecdb[rlen], 0, pad_len);
ecdb_ahdr->ahslength = cpu_to_be16(ahslength);
ecdb_ahdr->ahstype = ISCSI_AHSTYPE_CDB;
ecdb_ahdr->reserved = 0;
memcpy(ecdb_ahdr->ecdb, cmd->cmnd + ISCSI_CDB_SIZE, rlen);
ISCSI_DBG_SESSION(task->conn->session,
"iscsi_prep_ecdb_ahs: varlen_cdb_len %d "
"rlen %d pad_len %d ahs_length %d iscsi_headers_size "
"%u\n", cmd->cmd_len, rlen, pad_len, ahslength,
task->hdr_len);
return 0;
}
static int iscsi_prep_bidi_ahs(struct iscsi_task *task)
{
struct scsi_cmnd *sc = task->sc;
struct iscsi_rlength_ahdr *rlen_ahdr;
int rc;
rlen_ahdr = iscsi_next_hdr(task);
rc = iscsi_add_hdr(task, sizeof(*rlen_ahdr));
if (rc)
return rc;
rlen_ahdr->ahslength =
cpu_to_be16(sizeof(rlen_ahdr->read_length) +
sizeof(rlen_ahdr->reserved));
rlen_ahdr->ahstype = ISCSI_AHSTYPE_RLENGTH;
rlen_ahdr->reserved = 0;
rlen_ahdr->read_length = cpu_to_be32(scsi_in(sc)->length);
ISCSI_DBG_SESSION(task->conn->session,
"bidi-in rlen_ahdr->read_length(%d) "
"rlen_ahdr->ahslength(%d)\n",
be32_to_cpu(rlen_ahdr->read_length),
be16_to_cpu(rlen_ahdr->ahslength));
return 0;
}
/**
* iscsi_check_tmf_restrictions - check if a task is affected by TMF
* @task: iscsi task
* @opcode: opcode to check for
*
* During TMF a task has to be checked if it's affected.
* All unrelated I/O can be passed through, but I/O to the
* affected LUN should be restricted.
* If 'fast_abort' is set we won't be sending any I/O to the
* affected LUN.
* Otherwise the target is waiting for all TTTs to be completed,
* so we have to send all outstanding Data-Out PDUs to the target.
*/
static int iscsi_check_tmf_restrictions(struct iscsi_task *task, int opcode)
{
struct iscsi_conn *conn = task->conn;
struct iscsi_tm *tmf = &conn->tmhdr;
unsigned int hdr_lun;
if (conn->tmf_state == TMF_INITIAL)
return 0;
if ((tmf->opcode & ISCSI_OPCODE_MASK) != ISCSI_OP_SCSI_TMFUNC)
return 0;
switch (ISCSI_TM_FUNC_VALUE(tmf)) {
case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
/*
* Allow PDUs for unrelated LUNs
*/
hdr_lun = scsilun_to_int((struct scsi_lun *)tmf->lun);
if (hdr_lun != task->sc->device->lun)
return 0;
/* fall through */
case ISCSI_TM_FUNC_TARGET_WARM_RESET:
/*
* Fail all SCSI cmd PDUs
*/
if (opcode != ISCSI_OP_SCSI_DATA_OUT) {
iscsi_conn_printk(KERN_INFO, conn,
"task [op %x/%x itt "
"0x%x/0x%x] "
"rejected.\n",
task->hdr->opcode, opcode,
task->itt, task->hdr_itt);
return -EACCES;
}
/*
* And also all data-out PDUs in response to R2T
* if fast_abort is set.
*/
if (conn->session->fast_abort) {
iscsi_conn_printk(KERN_INFO, conn,
"task [op %x/%x itt "
"0x%x/0x%x] fast abort.\n",
task->hdr->opcode, opcode,
task->itt, task->hdr_itt);
return -EACCES;
}
break;
case ISCSI_TM_FUNC_ABORT_TASK:
/*
* the caller has already checked if the task
* they want to abort was in the pending queue so if
* we are here the cmd pdu has gone out already, and
* we will only hit this for data-outs
*/
if (opcode == ISCSI_OP_SCSI_DATA_OUT &&
task->hdr_itt == tmf->rtt) {
ISCSI_DBG_SESSION(conn->session,
"Preventing task %x/%x from sending "
"data-out due to abort task in "
"progress\n", task->itt,
task->hdr_itt);
return -EACCES;
}
break;
}
return 0;
}
/**
* iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
* @task: iscsi task
*
* Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
* fields like dlength or final based on how much data it sends
*/
static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
{
struct iscsi_conn *conn = task->conn;
struct iscsi_session *session = conn->session;
struct scsi_cmnd *sc = task->sc;
struct iscsi_cmd *hdr;
unsigned hdrlength, cmd_len;
itt_t itt;
int rc;
rc = iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_CMD);
if (rc)
return rc;
if (conn->session->tt->alloc_pdu) {
rc = conn->session->tt->alloc_pdu(task, ISCSI_OP_SCSI_CMD);
if (rc)
return rc;
}
hdr = (struct iscsi_cmd *) task->hdr;
itt = hdr->itt;
memset(hdr, 0, sizeof(*hdr));
if (session->tt->parse_pdu_itt)
hdr->itt = task->hdr_itt = itt;
else
hdr->itt = task->hdr_itt = build_itt(task->itt,
task->conn->session->age);
task->hdr_len = 0;
rc = iscsi_add_hdr(task, sizeof(*hdr));
if (rc)
return rc;
hdr->opcode = ISCSI_OP_SCSI_CMD;
hdr->flags = ISCSI_ATTR_SIMPLE;
int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
memcpy(task->lun, hdr->lun, sizeof(task->lun));
hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
cmd_len = sc->cmd_len;
if (cmd_len < ISCSI_CDB_SIZE)
memset(&hdr->cdb[cmd_len], 0, ISCSI_CDB_SIZE - cmd_len);
else if (cmd_len > ISCSI_CDB_SIZE) {
rc = iscsi_prep_ecdb_ahs(task);
if (rc)
return rc;
cmd_len = ISCSI_CDB_SIZE;
}
memcpy(hdr->cdb, sc->cmnd, cmd_len);
task->imm_count = 0;
if (scsi_bidi_cmnd(sc)) {
hdr->flags |= ISCSI_FLAG_CMD_READ;
rc = iscsi_prep_bidi_ahs(task);
if (rc)
return rc;
}
if (sc->sc_data_direction == DMA_TO_DEVICE) {
unsigned out_len = scsi_out(sc)->length;
struct iscsi_r2t_info *r2t = &task->unsol_r2t;
hdr->data_length = cpu_to_be32(out_len);
hdr->flags |= ISCSI_FLAG_CMD_WRITE;
/*
* Write counters:
*
* imm_count bytes to be sent right after
* SCSI PDU Header
*
* unsol_count bytes(as Data-Out) to be sent
* without R2T ack right after
* immediate data
*
* r2t data_length bytes to be sent via R2T ack's
*
* pad_count bytes to be sent as zero-padding
*/
memset(r2t, 0, sizeof(*r2t));
if (session->imm_data_en) {
if (out_len >= session->first_burst)
task->imm_count = min(session->first_burst,
conn->max_xmit_dlength);
else
task->imm_count = min(out_len,
conn->max_xmit_dlength);
hton24(hdr->dlength, task->imm_count);
} else
zero_data(hdr->dlength);
if (!session->initial_r2t_en) {
r2t->data_length = min(session->first_burst, out_len) -
task->imm_count;
r2t->data_offset = task->imm_count;
r2t->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
r2t->exp_statsn = cpu_to_be32(conn->exp_statsn);
}
if (!task->unsol_r2t.data_length)
/* No unsolicit Data-Out's */
hdr->flags |= ISCSI_FLAG_CMD_FINAL;
} else {
hdr->flags |= ISCSI_FLAG_CMD_FINAL;
zero_data(hdr->dlength);
hdr->data_length = cpu_to_be32(scsi_in(sc)->length);
if (sc->sc_data_direction == DMA_FROM_DEVICE)
hdr->flags |= ISCSI_FLAG_CMD_READ;
}
/* calculate size of additional header segments (AHSs) */
hdrlength = task->hdr_len - sizeof(*hdr);
WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
hdrlength /= ISCSI_PAD_LEN;
WARN_ON(hdrlength >= 256);
hdr->hlength = hdrlength & 0xFF;
if (session->tt->init_task && session->tt->init_task(task))
return -EIO;
task->state = ISCSI_TASK_RUNNING;
hdr->cmdsn = task->cmdsn = cpu_to_be32(session->cmdsn);
session->cmdsn++;
conn->scsicmd_pdus_cnt++;
ISCSI_DBG_SESSION(session, "iscsi prep [%s cid %d sc %p cdb 0x%x "
"itt 0x%x len %d bidi_len %d cmdsn %d win %d]\n",
scsi_bidi_cmnd(sc) ? "bidirectional" :
sc->sc_data_direction == DMA_TO_DEVICE ?
"write" : "read", conn->id, sc, sc->cmnd[0],
task->itt, scsi_bufflen(sc),
scsi_bidi_cmnd(sc) ? scsi_in(sc)->length : 0,
session->cmdsn,
session->max_cmdsn - session->exp_cmdsn + 1);
return 0;
}
/**
* iscsi_free_task - free a task
* @task: iscsi cmd task
*
* Must be called with session lock.
* This function returns the scsi command to scsi-ml or cleans
* up mgmt tasks then returns the task to the pool.
*/
static void iscsi_free_task(struct iscsi_task *task)
{
struct iscsi_conn *conn = task->conn;
struct iscsi_session *session = conn->session;
struct scsi_cmnd *sc = task->sc;
ISCSI_DBG_SESSION(session, "freeing task itt 0x%x state %d sc %p\n",
task->itt, task->state, task->sc);
session->tt->cleanup_task(task);
task->state = ISCSI_TASK_FREE;
task->sc = NULL;
/*
* login task is preallocated so do not free
*/
if (conn->login_task == task)
return;
kfifo_in(&session->cmdpool.queue, (void*)&task, sizeof(void*));
if (sc) {
task->sc = NULL;
/* SCSI eh reuses commands to verify us */
sc->SCp.ptr = NULL;
/*
* queue command may call this to free the task, but
* not have setup the sc callback
*/
if (sc->scsi_done)
sc->scsi_done(sc);
}
}
void __iscsi_get_task(struct iscsi_task *task)
{
atomic_inc(&task->refcount);
}
EXPORT_SYMBOL_GPL(__iscsi_get_task);
static void __iscsi_put_task(struct iscsi_task *task)
{
if (atomic_dec_and_test(&task->refcount))
iscsi_free_task(task);
}
void iscsi_put_task(struct iscsi_task *task)
{
struct iscsi_session *session = task->conn->session;
spin_lock_bh(&session->lock);
__iscsi_put_task(task);
spin_unlock_bh(&session->lock);
}
EXPORT_SYMBOL_GPL(iscsi_put_task);
/**
* iscsi_complete_task - finish a task
* @task: iscsi cmd task
* @state: state to complete task with
*
* Must be called with session lock.
*/
static void iscsi_complete_task(struct iscsi_task *task, int state)
{
struct iscsi_conn *conn = task->conn;
ISCSI_DBG_SESSION(conn->session,
"complete task itt 0x%x state %d sc %p\n",
task->itt, task->state, task->sc);
if (task->state == ISCSI_TASK_COMPLETED ||
task->state == ISCSI_TASK_ABRT_TMF ||
task->state == ISCSI_TASK_ABRT_SESS_RECOV)
return;
WARN_ON_ONCE(task->state == ISCSI_TASK_FREE);
task->state = state;
if (!list_empty(&task->running))
list_del_init(&task->running);
if (conn->task == task)
conn->task = NULL;
if (conn->ping_task == task)
conn->ping_task = NULL;
/* release get from queueing */
__iscsi_put_task(task);
}
/**
* iscsi_complete_scsi_task - finish scsi task normally
* @task: iscsi task for scsi cmd
* @exp_cmdsn: expected cmd sn in cpu format
* @max_cmdsn: max cmd sn in cpu format
*
* This is used when drivers do not need or cannot perform
* lower level pdu processing.
*
* Called with session lock
*/
void iscsi_complete_scsi_task(struct iscsi_task *task,
uint32_t exp_cmdsn, uint32_t max_cmdsn)
{
struct iscsi_conn *conn = task->conn;
ISCSI_DBG_SESSION(conn->session, "[itt 0x%x]\n", task->itt);
conn->last_recv = jiffies;
__iscsi_update_cmdsn(conn->session, exp_cmdsn, max_cmdsn);
iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
}
EXPORT_SYMBOL_GPL(iscsi_complete_scsi_task);
/*
* session lock must be held and if not called for a task that is
* still pending or from the xmit thread, then xmit thread must
* be suspended.
*/
static void fail_scsi_task(struct iscsi_task *task, int err)
{
struct iscsi_conn *conn = task->conn;
struct scsi_cmnd *sc;
int state;
/*
* if a command completes and we get a successful tmf response
* we will hit this because the scsi eh abort code does not take
* a ref to the task.
*/
sc = task->sc;
if (!sc)
return;
if (task->state == ISCSI_TASK_PENDING) {
/*
* cmd never made it to the xmit thread, so we should not count
* the cmd in the sequencing
*/
conn->session->queued_cmdsn--;
/* it was never sent so just complete like normal */
state = ISCSI_TASK_COMPLETED;
} else if (err == DID_TRANSPORT_DISRUPTED)
state = ISCSI_TASK_ABRT_SESS_RECOV;
else
state = ISCSI_TASK_ABRT_TMF;
sc->result = err << 16;
if (!scsi_bidi_cmnd(sc))
scsi_set_resid(sc, scsi_bufflen(sc));
else {
scsi_out(sc)->resid = scsi_out(sc)->length;
scsi_in(sc)->resid = scsi_in(sc)->length;
}
iscsi_complete_task(task, state);
}
static int iscsi_prep_mgmt_task(struct iscsi_conn *conn,
struct iscsi_task *task)
{
struct iscsi_session *session = conn->session;
struct iscsi_hdr *hdr = task->hdr;
struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
return -ENOTCONN;
if (opcode != ISCSI_OP_LOGIN && opcode != ISCSI_OP_TEXT)
nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
/*
* pre-format CmdSN for outgoing PDU.
*/
nop->cmdsn = cpu_to_be32(session->cmdsn);
if (hdr->itt != RESERVED_ITT) {
/*
* TODO: We always use immediate for normal session pdus.
* If we start to send tmfs or nops as non-immediate then
* we should start checking the cmdsn numbers for mgmt tasks.
*
* During discovery sessions iscsid sends TEXT as non immediate,
* but we always only send one PDU at a time.
*/
if (conn->c_stage == ISCSI_CONN_STARTED &&
!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
session->queued_cmdsn++;
session->cmdsn++;
}
}
if (session->tt->init_task && session->tt->init_task(task))
return -EIO;
if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
session->state = ISCSI_STATE_LOGGING_OUT;
task->state = ISCSI_TASK_RUNNING;
ISCSI_DBG_SESSION(session, "mgmtpdu [op 0x%x hdr->itt 0x%x "
"datalen %d]\n", hdr->opcode & ISCSI_OPCODE_MASK,
hdr->itt, task->data_count);
return 0;
}
static struct iscsi_task *
__iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
char *data, uint32_t data_size)
{
struct iscsi_session *session = conn->session;
struct iscsi_host *ihost = shost_priv(session->host);
uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
struct iscsi_task *task;
itt_t itt;
if (session->state == ISCSI_STATE_TERMINATE)
return NULL;
if (opcode == ISCSI_OP_LOGIN || opcode == ISCSI_OP_TEXT) {
/*
* Login and Text are sent serially, in
* request-followed-by-response sequence.
* Same task can be used. Same ITT must be used.
* Note that login_task is preallocated at conn_create().
*/
if (conn->login_task->state != ISCSI_TASK_FREE) {
iscsi_conn_printk(KERN_ERR, conn, "Login/Text in "
"progress. Cannot start new task.\n");
return NULL;
}
task = conn->login_task;
} else {
if (session->state != ISCSI_STATE_LOGGED_IN)
return NULL;
BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
if (!kfifo_out(&session->cmdpool.queue,
(void*)&task, sizeof(void*)))
return NULL;
}
/*
* released in complete pdu for task we expect a response for, and
* released by the lld when it has transmitted the task for
* pdus we do not expect a response for.
*/
atomic_set(&task->refcount, 1);
task->conn = conn;
task->sc = NULL;
INIT_LIST_HEAD(&task->running);
task->state = ISCSI_TASK_PENDING;
if (data_size) {
memcpy(task->data, data, data_size);
task->data_count = data_size;
} else
task->data_count = 0;
if (conn->session->tt->alloc_pdu) {
if (conn->session->tt->alloc_pdu(task, hdr->opcode)) {
iscsi_conn_printk(KERN_ERR, conn, "Could not allocate "
"pdu for mgmt task.\n");
goto free_task;
}
}
itt = task->hdr->itt;
task->hdr_len = sizeof(struct iscsi_hdr);
memcpy(task->hdr, hdr, sizeof(struct iscsi_hdr));
if (hdr->itt != RESERVED_ITT) {
if (session->tt->parse_pdu_itt)
task->hdr->itt = itt;
else
task->hdr->itt = build_itt(task->itt,
task->conn->session->age);
}
if (!ihost->workq) {
if (iscsi_prep_mgmt_task(conn, task))
goto free_task;
if (session->tt->xmit_task(task))
goto free_task;
} else {
list_add_tail(&task->running, &conn->mgmtqueue);
iscsi_conn_queue_work(conn);
}
return task;
free_task:
__iscsi_put_task(task);
return NULL;
}
int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
char *data, uint32_t data_size)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_session *session = conn->session;
int err = 0;
spin_lock_bh(&session->lock);
if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
err = -EPERM;
spin_unlock_bh(&session->lock);
return err;
}
EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
/**
* iscsi_cmd_rsp - SCSI Command Response processing
* @conn: iscsi connection
* @hdr: iscsi header
* @task: scsi command task
* @data: cmd data buffer
* @datalen: len of buffer
*
* iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
* then completes the command and task.
**/
static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
struct iscsi_task *task, char *data,
int datalen)
{
struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
struct iscsi_session *session = conn->session;
struct scsi_cmnd *sc = task->sc;
iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
sc->result = (DID_OK << 16) | rhdr->cmd_status;
if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
sc->result = DID_ERROR << 16;
goto out;
}
if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
uint16_t senselen;
if (datalen < 2) {
invalid_datalen:
iscsi_conn_printk(KERN_ERR, conn,
"Got CHECK_CONDITION but invalid data "
"buffer size of %d\n", datalen);
sc->result = DID_BAD_TARGET << 16;
goto out;
}
senselen = get_unaligned_be16(data);
if (datalen < senselen)
goto invalid_datalen;
memcpy(sc->sense_buffer, data + 2,
min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
ISCSI_DBG_SESSION(session, "copied %d bytes of sense\n",
min_t(uint16_t, senselen,
SCSI_SENSE_BUFFERSIZE));
}
if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {
int res_count = be32_to_cpu(rhdr->bi_residual_count);
if (scsi_bidi_cmnd(sc) && res_count > 0 &&
(rhdr->flags & ISCSI_FLAG_CMD_BIDI_OVERFLOW ||
res_count <= scsi_in(sc)->length))
scsi_in(sc)->resid = res_count;
else
sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
}
if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
ISCSI_FLAG_CMD_OVERFLOW)) {
int res_count = be32_to_cpu(rhdr->residual_count);
if (res_count > 0 &&
(rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
res_count <= scsi_bufflen(sc)))
/* write side for bidi or uni-io set_resid */
scsi_set_resid(sc, res_count);
else
sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
}
out:
ISCSI_DBG_SESSION(session, "cmd rsp done [sc %p res %d itt 0x%x]\n",
sc, sc->result, task->itt);
conn->scsirsp_pdus_cnt++;
iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
}
/**
* iscsi_data_in_rsp - SCSI Data-In Response processing
* @conn: iscsi connection
* @hdr: iscsi pdu
* @task: scsi command task
**/
static void
iscsi_data_in_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
struct iscsi_task *task)
{
struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)hdr;
struct scsi_cmnd *sc = task->sc;
if (!(rhdr->flags & ISCSI_FLAG_DATA_STATUS))
return;
iscsi_update_cmdsn(conn->session, (struct iscsi_nopin *)hdr);
sc->result = (DID_OK << 16) | rhdr->cmd_status;
conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW |
ISCSI_FLAG_DATA_OVERFLOW)) {
int res_count = be32_to_cpu(rhdr->residual_count);
if (res_count > 0 &&
(rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
res_count <= scsi_in(sc)->length))
scsi_in(sc)->resid = res_count;
else
sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
}
ISCSI_DBG_SESSION(conn->session, "data in with status done "
"[sc %p res %d itt 0x%x]\n",
sc, sc->result, task->itt);
conn->scsirsp_pdus_cnt++;
iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
}
static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
{
struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
conn->tmfrsp_pdus_cnt++;
if (conn->tmf_state != TMF_QUEUED)
return;
if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
conn->tmf_state = TMF_SUCCESS;
else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
conn->tmf_state = TMF_NOT_FOUND;
else
conn->tmf_state = TMF_FAILED;
wake_up(&conn->ehwait);
}
static void iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
{
struct iscsi_nopout hdr;
struct iscsi_task *task;
if (!rhdr && conn->ping_task)
return;
memset(&hdr, 0, sizeof(struct iscsi_nopout));
hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
hdr.flags = ISCSI_FLAG_CMD_FINAL;
if (rhdr) {
memcpy(hdr.lun, rhdr->lun, 8);
hdr.ttt = rhdr->ttt;
hdr.itt = RESERVED_ITT;
} else
hdr.ttt = RESERVED_ITT;
task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
if (!task)
iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
else if (!rhdr) {
/* only track our nops */
conn->ping_task = task;
conn->last_ping = jiffies;
}
}
static int iscsi_nop_out_rsp(struct iscsi_task *task,
struct iscsi_nopin *nop, char *data, int datalen)
{
struct iscsi_conn *conn = task->conn;
int rc = 0;
if (conn->ping_task != task) {
/*
* If this is not in response to one of our
* nops then it must be from userspace.
*/
if (iscsi_recv_pdu(conn->cls_conn, (struct iscsi_hdr *)nop,
data, datalen))
rc = ISCSI_ERR_CONN_FAILED;
} else
mod_timer(&conn->transport_timer, jiffies + conn->recv_timeout);
iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
return rc;
}
static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
char *data, int datalen)
{
struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
struct iscsi_hdr rejected_pdu;
int opcode, rc = 0;
conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
if (ntoh24(reject->dlength) > datalen ||
ntoh24(reject->dlength) < sizeof(struct iscsi_hdr)) {
iscsi_conn_printk(KERN_ERR, conn, "Cannot handle rejected "
"pdu. Invalid data length (pdu dlength "
"%u, datalen %d\n", ntoh24(reject->dlength),
datalen);
return ISCSI_ERR_PROTO;
}
memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
opcode = rejected_pdu.opcode & ISCSI_OPCODE_MASK;
switch (reject->reason) {
case ISCSI_REASON_DATA_DIGEST_ERROR:
iscsi_conn_printk(KERN_ERR, conn,
"pdu (op 0x%x itt 0x%x) rejected "
"due to DataDigest error.\n",
rejected_pdu.itt, opcode);
break;
case ISCSI_REASON_IMM_CMD_REJECT:
iscsi_conn_printk(KERN_ERR, conn,
"pdu (op 0x%x itt 0x%x) rejected. Too many "
"immediate commands.\n",
rejected_pdu.itt, opcode);
/*
* We only send one TMF at a time so if the target could not
* handle it, then it should get fixed (RFC mandates that
* a target can handle one immediate TMF per conn).
*
* For nops-outs, we could have sent more than one if
* the target is sending us lots of nop-ins
*/
if (opcode != ISCSI_OP_NOOP_OUT)
return 0;
if (rejected_pdu.itt == cpu_to_be32(ISCSI_RESERVED_TAG))
/*
* nop-out in response to target's nop-out rejected.
* Just resend.
*/
iscsi_send_nopout(conn,
(struct iscsi_nopin*)&rejected_pdu);
else {
struct iscsi_task *task;
/*
* Our nop as ping got dropped. We know the target
* and transport are ok so just clean up
*/
task = iscsi_itt_to_task(conn, rejected_pdu.itt);
if (!task) {
iscsi_conn_printk(KERN_ERR, conn,
"Invalid pdu reject. Could "
"not lookup rejected task.\n");
rc = ISCSI_ERR_BAD_ITT;
} else
rc = iscsi_nop_out_rsp(task,
(struct iscsi_nopin*)&rejected_pdu,
NULL, 0);
}
break;
default:
iscsi_conn_printk(KERN_ERR, conn,
"pdu (op 0x%x itt 0x%x) rejected. Reason "
"code 0x%x\n", rejected_pdu.itt,
rejected_pdu.opcode, reject->reason);
break;
}
return rc;
}
/**
* iscsi_itt_to_task - look up task by itt
* @conn: iscsi connection
* @itt: itt
*
* This should be used for mgmt tasks like login and nops, or if
* the LDD's itt space does not include the session age.
*
* The session lock must be held.
*/
struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *conn, itt_t itt)
{
struct iscsi_session *session = conn->session;
int i;
if (itt == RESERVED_ITT)
return NULL;
if (session->tt->parse_pdu_itt)
session->tt->parse_pdu_itt(conn, itt, &i, NULL);
else
i = get_itt(itt);
if (i >= session->cmds_max)
return NULL;
return session->cmds[i];
}
EXPORT_SYMBOL_GPL(iscsi_itt_to_task);
/**
* __iscsi_complete_pdu - complete pdu
* @conn: iscsi conn
* @hdr: iscsi header
* @data: data buffer
* @datalen: len of data buffer
*
* Completes pdu processing by freeing any resources allocated at
* queuecommand or send generic. session lock must be held and verify
* itt must have been called.
*/
int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
char *data, int datalen)
{
struct iscsi_session *session = conn->session;
int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
struct iscsi_task *task;
uint32_t itt;
conn->last_recv = jiffies;
rc = iscsi_verify_itt(conn, hdr->itt);
if (rc)
return rc;
if (hdr->itt != RESERVED_ITT)
itt = get_itt(hdr->itt);
else
itt = ~0U;
ISCSI_DBG_SESSION(session, "[op 0x%x cid %d itt 0x%x len %d]\n",
opcode, conn->id, itt, datalen);
if (itt == ~0U) {
iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
switch(opcode) {
case ISCSI_OP_NOOP_IN:
if (datalen) {
rc = ISCSI_ERR_PROTO;
break;
}
if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
break;
iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
break;
case ISCSI_OP_REJECT:
rc = iscsi_handle_reject(conn, hdr, data, datalen);
break;
case ISCSI_OP_ASYNC_EVENT:
conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
rc = ISCSI_ERR_CONN_FAILED;
break;
default:
rc = ISCSI_ERR_BAD_OPCODE;
break;
}
goto out;
}
switch(opcode) {
case ISCSI_OP_SCSI_CMD_RSP:
case ISCSI_OP_SCSI_DATA_IN:
task = iscsi_itt_to_ctask(conn, hdr->itt);
if (!task)
return ISCSI_ERR_BAD_ITT;
task->last_xfer = jiffies;
break;
case ISCSI_OP_R2T:
/*
* LLD handles R2Ts if they need to.
*/
return 0;
case ISCSI_OP_LOGOUT_RSP:
case ISCSI_OP_LOGIN_RSP:
case ISCSI_OP_TEXT_RSP:
case ISCSI_OP_SCSI_TMFUNC_RSP:
case ISCSI_OP_NOOP_IN:
task = iscsi_itt_to_task(conn, hdr->itt);
if (!task)
return ISCSI_ERR_BAD_ITT;
break;
default:
return ISCSI_ERR_BAD_OPCODE;
}
switch(opcode) {
case ISCSI_OP_SCSI_CMD_RSP:
iscsi_scsi_cmd_rsp(conn, hdr, task, data, datalen);
break;
case ISCSI_OP_SCSI_DATA_IN:
iscsi_data_in_rsp(conn, hdr, task);
break;
case ISCSI_OP_LOGOUT_RSP:
iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
if (datalen) {
rc = ISCSI_ERR_PROTO;
break;
}
conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
goto recv_pdu;
case ISCSI_OP_LOGIN_RSP:
case ISCSI_OP_TEXT_RSP:
iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
/*
* login related PDU's exp_statsn is handled in
* userspace
*/
goto recv_pdu;
case ISCSI_OP_SCSI_TMFUNC_RSP:
iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
if (datalen) {
rc = ISCSI_ERR_PROTO;
break;
}
iscsi_tmf_rsp(conn, hdr);
iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
break;
case ISCSI_OP_NOOP_IN:
iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) || datalen) {
rc = ISCSI_ERR_PROTO;
break;
}
conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
rc = iscsi_nop_out_rsp(task, (struct iscsi_nopin*)hdr,
data, datalen);
break;
default:
rc = ISCSI_ERR_BAD_OPCODE;
break;
}
out:
return rc;
recv_pdu:
if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
rc = ISCSI_ERR_CONN_FAILED;
iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
return rc;
}
EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
char *data, int datalen)
{
int rc;
spin_lock(&conn->session->lock);
rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
spin_unlock(&conn->session->lock);
return rc;
}
EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
{
struct iscsi_session *session = conn->session;
int age = 0, i = 0;
if (itt == RESERVED_ITT)
return 0;
if (session->tt->parse_pdu_itt)
session->tt->parse_pdu_itt(conn, itt, &i, &age);
else {
i = get_itt(itt);
age = ((__force u32)itt >> ISCSI_AGE_SHIFT) & ISCSI_AGE_MASK;
}
if (age != session->age) {
iscsi_conn_printk(KERN_ERR, conn,
"received itt %x expected session age (%x)\n",
(__force u32)itt, session->age);
return ISCSI_ERR_BAD_ITT;
}
if (i >= session->cmds_max) {
iscsi_conn_printk(KERN_ERR, conn,
"received invalid itt index %u (max cmds "
"%u.\n", i, session->cmds_max);
return ISCSI_ERR_BAD_ITT;
}
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_verify_itt);
/**
* iscsi_itt_to_ctask - look up ctask by itt
* @conn: iscsi connection
* @itt: itt
*
* This should be used for cmd tasks.
*
* The session lock must be held.
*/
struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt)
{
struct iscsi_task *task;
if (iscsi_verify_itt(conn, itt))
return NULL;
task = iscsi_itt_to_task(conn, itt);
if (!task || !task->sc)
return NULL;
if (task->sc->SCp.phase != conn->session->age) {
iscsi_session_printk(KERN_ERR, conn->session,
"task's session age %d, expected %d\n",
task->sc->SCp.phase, conn->session->age);
return NULL;
}
return task;
}
EXPORT_SYMBOL_GPL(iscsi_itt_to_ctask);
void iscsi_session_failure(struct iscsi_session *session,
enum iscsi_err err)
{
struct iscsi_conn *conn;
struct device *dev;
unsigned long flags;
spin_lock_irqsave(&session->lock, flags);
conn = session->leadconn;
if (session->state == ISCSI_STATE_TERMINATE || !conn) {
spin_unlock_irqrestore(&session->lock, flags);
return;
}
dev = get_device(&conn->cls_conn->dev);
spin_unlock_irqrestore(&session->lock, flags);
if (!dev)
return;
/*
* if the host is being removed bypass the connection
* recovery initialization because we are going to kill
* the session.
*/
if (err == ISCSI_ERR_INVALID_HOST)
iscsi_conn_error_event(conn->cls_conn, err);
else
iscsi_conn_failure(conn, err);
put_device(dev);
}
EXPORT_SYMBOL_GPL(iscsi_session_failure);
void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
{
struct iscsi_session *session = conn->session;
unsigned long flags;
spin_lock_irqsave(&session->lock, flags);
if (session->state == ISCSI_STATE_FAILED) {
spin_unlock_irqrestore(&session->lock, flags);
return;
}
if (conn->stop_stage == 0)
session->state = ISCSI_STATE_FAILED;
spin_unlock_irqrestore(&session->lock, flags);
set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
iscsi_conn_error_event(conn->cls_conn, err);
}
EXPORT_SYMBOL_GPL(iscsi_conn_failure);
static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
{
struct iscsi_session *session = conn->session;
/*
* Check for iSCSI window and take care of CmdSN wrap-around
*/
if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
ISCSI_DBG_SESSION(session, "iSCSI CmdSN closed. ExpCmdSn "
"%u MaxCmdSN %u CmdSN %u/%u\n",
session->exp_cmdsn, session->max_cmdsn,
session->cmdsn, session->queued_cmdsn);
return -ENOSPC;
}
return 0;
}
static int iscsi_xmit_task(struct iscsi_conn *conn)
{
struct iscsi_task *task = conn->task;
int rc;
if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx))
return -ENODATA;
__iscsi_get_task(task);
spin_unlock_bh(&conn->session->lock);
rc = conn->session->tt->xmit_task(task);
spin_lock_bh(&conn->session->lock);
if (!rc) {
/* done with this task */
task->last_xfer = jiffies;
conn->task = NULL;
}
__iscsi_put_task(task);
return rc;
}
/**
* iscsi_requeue_task - requeue task to run from session workqueue
* @task: task to requeue
*
* LLDs that need to run a task from the session workqueue should call
* this. The session lock must be held. This should only be called
* by software drivers.
*/
void iscsi_requeue_task(struct iscsi_task *task)
{
struct iscsi_conn *conn = task->conn;
/*
* this may be on the requeue list already if the xmit_task callout
* is handling the r2ts while we are adding new ones
*/
if (list_empty(&task->running))
list_add_tail(&task->running, &conn->requeue);
iscsi_conn_queue_work(conn);
}
EXPORT_SYMBOL_GPL(iscsi_requeue_task);
/**
* iscsi_data_xmit - xmit any command into the scheduled connection
* @conn: iscsi connection
*
* Notes:
* The function can return -EAGAIN in which case the caller must
* re-schedule it again later or recover. '0' return code means
* successful xmit.
**/
static int iscsi_data_xmit(struct iscsi_conn *conn)
{
struct iscsi_task *task;
int rc = 0;
spin_lock_bh(&conn->session->lock);
if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
ISCSI_DBG_SESSION(conn->session, "Tx suspended!\n");
spin_unlock_bh(&conn->session->lock);
return -ENODATA;
}
if (conn->task) {
rc = iscsi_xmit_task(conn);
if (rc)
goto done;
}
/*
* process mgmt pdus like nops before commands since we should
* only have one nop-out as a ping from us and targets should not
* overflow us with nop-ins
*/
check_mgmt:
while (!list_empty(&conn->mgmtqueue)) {
conn->task = list_entry(conn->mgmtqueue.next,
struct iscsi_task, running);
list_del_init(&conn->task->running);
if (iscsi_prep_mgmt_task(conn, conn->task)) {
__iscsi_put_task(conn->task);
conn->task = NULL;
continue;
}
rc = iscsi_xmit_task(conn);
if (rc)
goto done;
}
/* process pending command queue */
while (!list_empty(&conn->cmdqueue)) {
conn->task = list_entry(conn->cmdqueue.next, struct iscsi_task,
running);
list_del_init(&conn->task->running);
if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
fail_scsi_task(conn->task, DID_IMM_RETRY);
continue;
}
rc = iscsi_prep_scsi_cmd_pdu(conn->task);
if (rc) {
if (rc == -ENOMEM || rc == -EACCES) {
list_add_tail(&conn->task->running,
&conn->cmdqueue);
conn->task = NULL;
goto done;
} else
fail_scsi_task(conn->task, DID_ABORT);
continue;
}
rc = iscsi_xmit_task(conn);
if (rc)
goto done;
/*
* we could continuously get new task requests so
* we need to check the mgmt queue for nops that need to
* be sent to aviod starvation
*/
if (!list_empty(&conn->mgmtqueue))
goto check_mgmt;
}
while (!list_empty(&conn->requeue)) {
/*
* we always do fastlogout - conn stop code will clean up.
*/
if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
break;
task = list_entry(conn->requeue.next, struct iscsi_task,
running);
if (iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_DATA_OUT))
break;
conn->task = task;
list_del_init(&conn->task->running);
conn->task->state = ISCSI_TASK_RUNNING;
rc = iscsi_xmit_task(conn);
if (rc)
goto done;
if (!list_empty(&conn->mgmtqueue))
goto check_mgmt;
}
spin_unlock_bh(&conn->session->lock);
return -ENODATA;
done:
spin_unlock_bh(&conn->session->lock);
return rc;
}
static void iscsi_xmitworker(struct work_struct *work)
{
struct iscsi_conn *conn =
container_of(work, struct iscsi_conn, xmitwork);
int rc;
/*
* serialize Xmit worker on a per-connection basis.
*/
do {
rc = iscsi_data_xmit(conn);
} while (rc >= 0 || rc == -EAGAIN);
}
static inline struct iscsi_task *iscsi_alloc_task(struct iscsi_conn *conn,
struct scsi_cmnd *sc)
{
struct iscsi_task *task;
if (!kfifo_out(&conn->session->cmdpool.queue,
(void *) &task, sizeof(void *)))
return NULL;
sc->SCp.phase = conn->session->age;
sc->SCp.ptr = (char *) task;
atomic_set(&task->refcount, 1);
task->state = ISCSI_TASK_PENDING;
task->conn = conn;
task->sc = sc;
task->have_checked_conn = false;
task->last_timeout = jiffies;
task->last_xfer = jiffies;
INIT_LIST_HEAD(&task->running);
return task;
}
enum {
FAILURE_BAD_HOST = 1,
FAILURE_SESSION_FAILED,
FAILURE_SESSION_FREED,
FAILURE_WINDOW_CLOSED,
FAILURE_OOM,
FAILURE_SESSION_TERMINATE,
FAILURE_SESSION_IN_RECOVERY,
FAILURE_SESSION_RECOVERY_TIMEOUT,
FAILURE_SESSION_LOGGING_OUT,
FAILURE_SESSION_NOT_READY,
};
int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
{
struct iscsi_cls_session *cls_session;
struct Scsi_Host *host;
struct iscsi_host *ihost;
int reason = 0;
struct iscsi_session *session;
struct iscsi_conn *conn;
struct iscsi_task *task = NULL;
sc->scsi_done = done;
sc->result = 0;
sc->SCp.ptr = NULL;
host = sc->device->host;
ihost = shost_priv(host);
spin_unlock(host->host_lock);
cls_session = starget_to_session(scsi_target(sc->device));
session = cls_session->dd_data;
spin_lock(&session->lock);
reason = iscsi_session_chkready(cls_session);
if (reason) {
sc->result = reason;
goto fault;
}
if (session->state != ISCSI_STATE_LOGGED_IN) {
/*
* to handle the race between when we set the recovery state
* and block the session we requeue here (commands could
* be entering our queuecommand while a block is starting
* up because the block code is not locked)
*/
switch (session->state) {
case ISCSI_STATE_FAILED:
case ISCSI_STATE_IN_RECOVERY:
reason = FAILURE_SESSION_IN_RECOVERY;
sc->result = DID_IMM_RETRY << 16;
break;
case ISCSI_STATE_LOGGING_OUT:
reason = FAILURE_SESSION_LOGGING_OUT;
sc->result = DID_IMM_RETRY << 16;
break;
case ISCSI_STATE_RECOVERY_FAILED:
reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
sc->result = DID_TRANSPORT_FAILFAST << 16;
break;
case ISCSI_STATE_TERMINATE:
reason = FAILURE_SESSION_TERMINATE;
sc->result = DID_NO_CONNECT << 16;
break;
default:
reason = FAILURE_SESSION_FREED;
sc->result = DID_NO_CONNECT << 16;
}
goto fault;
}
conn = session->leadconn;
if (!conn) {
reason = FAILURE_SESSION_FREED;
sc->result = DID_NO_CONNECT << 16;
goto fault;
}
if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
reason = FAILURE_SESSION_IN_RECOVERY;
sc->result = DID_REQUEUE;
goto fault;
}
if (iscsi_check_cmdsn_window_closed(conn)) {
reason = FAILURE_WINDOW_CLOSED;
goto reject;
}
task = iscsi_alloc_task(conn, sc);
if (!task) {
reason = FAILURE_OOM;
goto reject;
}
if (!ihost->workq) {
reason = iscsi_prep_scsi_cmd_pdu(task);
if (reason) {
if (reason == -ENOMEM || reason == -EACCES) {
reason = FAILURE_OOM;
goto prepd_reject;
} else {
sc->result = DID_ABORT << 16;
goto prepd_fault;
}
}
if (session->tt->xmit_task(task)) {
session->cmdsn--;
reason = FAILURE_SESSION_NOT_READY;
goto prepd_reject;
}
} else {
list_add_tail(&task->running, &conn->cmdqueue);
iscsi_conn_queue_work(conn);
}
session->queued_cmdsn++;
spin_unlock(&session->lock);
spin_lock(host->host_lock);
return 0;
prepd_reject:
sc->scsi_done = NULL;
iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
reject:
spin_unlock(&session->lock);
ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
sc->cmnd[0], reason);
spin_lock(host->host_lock);
return SCSI_MLQUEUE_TARGET_BUSY;
prepd_fault:
sc->scsi_done = NULL;
iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
fault:
spin_unlock(&session->lock);
ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n",
sc->cmnd[0], reason);
if (!scsi_bidi_cmnd(sc))
scsi_set_resid(sc, scsi_bufflen(sc));
else {
scsi_out(sc)->resid = scsi_out(sc)->length;
scsi_in(sc)->resid = scsi_in(sc)->length;
}
done(sc);
spin_lock(host->host_lock);
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_queuecommand);
int iscsi_change_queue_depth(struct scsi_device *sdev, int depth, int reason)
{
switch (reason) {
case SCSI_QDEPTH_DEFAULT:
scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
break;
case SCSI_QDEPTH_QFULL:
scsi_track_queue_full(sdev, depth);
break;
case SCSI_QDEPTH_RAMP_UP:
scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
break;
default:
return -EOPNOTSUPP;
}
return sdev->queue_depth;
}
EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
int iscsi_target_alloc(struct scsi_target *starget)
{
struct iscsi_cls_session *cls_session = starget_to_session(starget);
struct iscsi_session *session = cls_session->dd_data;
starget->can_queue = session->scsi_cmds_max;
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_target_alloc);
static void iscsi_tmf_timedout(unsigned long data)
{
struct iscsi_conn *conn = (struct iscsi_conn *)data;
struct iscsi_session *session = conn->session;
spin_lock(&session->lock);
if (conn->tmf_state == TMF_QUEUED) {
conn->tmf_state = TMF_TIMEDOUT;
ISCSI_DBG_EH(session, "tmf timedout\n");
/* unblock eh_abort() */
wake_up(&conn->ehwait);
}
spin_unlock(&session->lock);
}
static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
struct iscsi_tm *hdr, int age,
int timeout)
{
struct iscsi_session *session = conn->session;
struct iscsi_task *task;
task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
NULL, 0);
if (!task) {
spin_unlock_bh(&session->lock);
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
spin_lock_bh(&session->lock);
ISCSI_DBG_EH(session, "tmf exec failure\n");
return -EPERM;
}
conn->tmfcmd_pdus_cnt++;
conn->tmf_timer.expires = timeout * HZ + jiffies;
conn->tmf_timer.function = iscsi_tmf_timedout;
conn->tmf_timer.data = (unsigned long)conn;
add_timer(&conn->tmf_timer);
ISCSI_DBG_EH(session, "tmf set timeout\n");
spin_unlock_bh(&session->lock);
mutex_unlock(&session->eh_mutex);
/*
* block eh thread until:
*
* 1) tmf response
* 2) tmf timeout
* 3) session is terminated or restarted or userspace has
* given up on recovery
*/
wait_event_interruptible(conn->ehwait, age != session->age ||
session->state != ISCSI_STATE_LOGGED_IN ||
conn->tmf_state != TMF_QUEUED);
if (signal_pending(current))
flush_signals(current);
del_timer_sync(&conn->tmf_timer);
mutex_lock(&session->eh_mutex);
spin_lock_bh(&session->lock);
/* if the session drops it will clean up the task */
if (age != session->age ||
session->state != ISCSI_STATE_LOGGED_IN)
return -ENOTCONN;
return 0;
}
/*
* Fail commands. session lock held and recv side suspended and xmit
* thread flushed
*/
static void fail_scsi_tasks(struct iscsi_conn *conn, unsigned lun,
int error)
{
struct iscsi_task *task;
int i;
for (i = 0; i < conn->session->cmds_max; i++) {
task = conn->session->cmds[i];
if (!task->sc || task->state == ISCSI_TASK_FREE)
continue;
if (lun != -1 && lun != task->sc->device->lun)
continue;
ISCSI_DBG_SESSION(conn->session,
"failing sc %p itt 0x%x state %d\n",
task->sc, task->itt, task->state);
fail_scsi_task(task, error);
}
}
/**
* iscsi_suspend_queue - suspend iscsi_queuecommand
* @conn: iscsi conn to stop queueing IO on
*
* This grabs the session lock to make sure no one is in
* xmit_task/queuecommand, and then sets suspend to prevent
* new commands from being queued. This only needs to be called
* by offload drivers that need to sync a path like ep disconnect
* with the iscsi_queuecommand/xmit_task. To start IO again libiscsi
* will call iscsi_start_tx and iscsi_unblock_session when in FFP.
*/
void iscsi_suspend_queue(struct iscsi_conn *conn)
{
spin_lock_bh(&conn->session->lock);
set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
spin_unlock_bh(&conn->session->lock);
}
EXPORT_SYMBOL_GPL(iscsi_suspend_queue);
/**
* iscsi_suspend_tx - suspend iscsi_data_xmit
* @conn: iscsi conn tp stop processing IO on.
*
* This function sets the suspend bit to prevent iscsi_data_xmit
* from sending new IO, and if work is queued on the xmit thread
* it will wait for it to be completed.
*/
void iscsi_suspend_tx(struct iscsi_conn *conn)
{
struct Scsi_Host *shost = conn->session->host;
struct iscsi_host *ihost = shost_priv(shost);
set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
if (ihost->workq)
flush_workqueue(ihost->workq);
}
EXPORT_SYMBOL_GPL(iscsi_suspend_tx);
static void iscsi_start_tx(struct iscsi_conn *conn)
{
clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
iscsi_conn_queue_work(conn);
}
/*
* We want to make sure a ping is in flight. It has timed out.
* And we are not busy processing a pdu that is making
* progress but got started before the ping and is taking a while
* to complete so the ping is just stuck behind it in a queue.
*/
static int iscsi_has_ping_timed_out(struct iscsi_conn *conn)
{
if (conn->ping_task &&
time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
(conn->ping_timeout * HZ), jiffies))
return 1;
else
return 0;
}
static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc)
{
enum blk_eh_timer_return rc = BLK_EH_NOT_HANDLED;
struct iscsi_task *task = NULL, *running_task;
struct iscsi_cls_session *cls_session;
struct iscsi_session *session;
struct iscsi_conn *conn;
int i;
cls_session = starget_to_session(scsi_target(sc->device));
session = cls_session->dd_data;
ISCSI_DBG_EH(session, "scsi cmd %p timedout\n", sc);
spin_lock(&session->lock);
if (session->state != ISCSI_STATE_LOGGED_IN) {
/*
* We are probably in the middle of iscsi recovery so let
* that complete and handle the error.
*/
rc = BLK_EH_RESET_TIMER;
goto done;
}
conn = session->leadconn;
if (!conn) {
/* In the middle of shuting down */
rc = BLK_EH_RESET_TIMER;
goto done;
}
task = (struct iscsi_task *)sc->SCp.ptr;
if (!task) {
/*
* Raced with completion. Just reset timer, and let it
* complete normally
*/
rc = BLK_EH_RESET_TIMER;
goto done;
}
/*
* If we have sent (at least queued to the network layer) a pdu or
* recvd one for the task since the last timeout ask for
* more time. If on the next timeout we have not made progress
* we can check if it is the task or connection when we send the
* nop as a ping.
*/
if (time_after(task->last_xfer, task->last_timeout)) {
ISCSI_DBG_EH(session, "Command making progress. Asking "
"scsi-ml for more time to complete. "
"Last data xfer at %lu. Last timeout was at "
"%lu\n.", task->last_xfer, task->last_timeout);
task->have_checked_conn = false;
rc = BLK_EH_RESET_TIMER;
goto done;
}
if (!conn->recv_timeout && !conn->ping_timeout)
goto done;
/*
* if the ping timedout then we are in the middle of cleaning up
* and can let the iscsi eh handle it
*/
if (iscsi_has_ping_timed_out(conn)) {
rc = BLK_EH_RESET_TIMER;
goto done;
}
for (i = 0; i < conn->session->cmds_max; i++) {
running_task = conn->session->cmds[i];
if (!running_task->sc || running_task == task ||
running_task->state != ISCSI_TASK_RUNNING)
continue;
/*
* Only check if cmds started before this one have made
* progress, or this could never fail
*/
if (time_after(running_task->sc->jiffies_at_alloc,
task->sc->jiffies_at_alloc))
continue;
if (time_after(running_task->last_xfer, task->last_timeout)) {
/*
* This task has not made progress, but a task
* started before us has transferred data since
* we started/last-checked. We could be queueing
* too many tasks or the LU is bad.
*
* If the device is bad the cmds ahead of us on
* other devs will complete, and this loop will
* eventually fail starting the scsi eh.
*/
ISCSI_DBG_EH(session, "Command has not made progress "
"but commands ahead of it have. "
"Asking scsi-ml for more time to "
"complete. Our last xfer vs running task "
"last xfer %lu/%lu. Last check %lu.\n",
task->last_xfer, running_task->last_xfer,
task->last_timeout);
rc = BLK_EH_RESET_TIMER;
goto done;
}
}
/* Assumes nop timeout is shorter than scsi cmd timeout */
if (task->have_checked_conn)
goto done;
/*
* Checking the transport already or nop from a cmd timeout still
* running
*/
if (conn->ping_task) {
task->have_checked_conn = true;
rc = BLK_EH_RESET_TIMER;
goto done;
}
/* Make sure there is a transport check done */
iscsi_send_nopout(conn, NULL);
task->have_checked_conn = true;
rc = BLK_EH_RESET_TIMER;
done:
if (task)
task->last_timeout = jiffies;
spin_unlock(&session->lock);
ISCSI_DBG_EH(session, "return %s\n", rc == BLK_EH_RESET_TIMER ?
"timer reset" : "nh");
return rc;
}
static void iscsi_check_transport_timeouts(unsigned long data)
{
struct iscsi_conn *conn = (struct iscsi_conn *)data;
struct iscsi_session *session = conn->session;
unsigned long recv_timeout, next_timeout = 0, last_recv;
spin_lock(&session->lock);
if (session->state != ISCSI_STATE_LOGGED_IN)
goto done;
recv_timeout = conn->recv_timeout;
if (!recv_timeout)
goto done;
recv_timeout *= HZ;
last_recv = conn->last_recv;
if (iscsi_has_ping_timed_out(conn)) {
iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
"expired, recv timeout %d, last rx %lu, "
"last ping %lu, now %lu\n",
conn->ping_timeout, conn->recv_timeout,
last_recv, conn->last_ping, jiffies);
spin_unlock(&session->lock);
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
return;
}
if (time_before_eq(last_recv + recv_timeout, jiffies)) {
/* send a ping to try to provoke some traffic */
ISCSI_DBG_CONN(conn, "Sending nopout as ping\n");
iscsi_send_nopout(conn, NULL);
next_timeout = conn->last_ping + (conn->ping_timeout * HZ);
} else
next_timeout = last_recv + recv_timeout;
ISCSI_DBG_CONN(conn, "Setting next tmo %lu\n", next_timeout);
mod_timer(&conn->transport_timer, next_timeout);
done:
spin_unlock(&session->lock);
}
static void iscsi_prep_abort_task_pdu(struct iscsi_task *task,
struct iscsi_tm *hdr)
{
memset(hdr, 0, sizeof(*hdr));
hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
hdr->flags |= ISCSI_FLAG_CMD_FINAL;
memcpy(hdr->lun, task->lun, sizeof(hdr->lun));
hdr->rtt = task->hdr_itt;
hdr->refcmdsn = task->cmdsn;
}
int iscsi_eh_abort(struct scsi_cmnd *sc)
{
struct iscsi_cls_session *cls_session;
struct iscsi_session *session;
struct iscsi_conn *conn;
struct iscsi_task *task;
struct iscsi_tm *hdr;
int rc, age;
cls_session = starget_to_session(scsi_target(sc->device));
session = cls_session->dd_data;
ISCSI_DBG_EH(session, "aborting sc %p\n", sc);
mutex_lock(&session->eh_mutex);
spin_lock_bh(&session->lock);
/*
* if session was ISCSI_STATE_IN_RECOVERY then we may not have
* got the command.
*/
if (!sc->SCp.ptr) {
ISCSI_DBG_EH(session, "sc never reached iscsi layer or "
"it completed.\n");
spin_unlock_bh(&session->lock);
mutex_unlock(&session->eh_mutex);
return SUCCESS;
}
/*
* If we are not logged in or we have started a new session
* then let the host reset code handle this
*/
if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
sc->SCp.phase != session->age) {
spin_unlock_bh(&session->lock);
mutex_unlock(&session->eh_mutex);
ISCSI_DBG_EH(session, "failing abort due to dropped "
"session.\n");
return FAILED;
}
conn = session->leadconn;
conn->eh_abort_cnt++;
age = session->age;
task = (struct iscsi_task *)sc->SCp.ptr;
ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n",
sc, task->itt);
/* task completed before time out */
if (!task->sc) {
ISCSI_DBG_EH(session, "sc completed while abort in progress\n");
goto success;
}
if (task->state == ISCSI_TASK_PENDING) {
fail_scsi_task(task, DID_ABORT);
goto success;
}
/* only have one tmf outstanding at a time */
if (conn->tmf_state != TMF_INITIAL)
goto failed;
conn->tmf_state = TMF_QUEUED;
hdr = &conn->tmhdr;
iscsi_prep_abort_task_pdu(task, hdr);
if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) {
rc = FAILED;
goto failed;
}
switch (conn->tmf_state) {
case TMF_SUCCESS:
spin_unlock_bh(&session->lock);
/*
* stop tx side incase the target had sent a abort rsp but
* the initiator was still writing out data.
*/
iscsi_suspend_tx(conn);
/*
* we do not stop the recv side because targets have been
* good and have never sent us a successful tmf response
* then sent more data for the cmd.
*/
spin_lock_bh(&session->lock);
fail_scsi_task(task, DID_ABORT);
conn->tmf_state = TMF_INITIAL;
memset(hdr, 0, sizeof(*hdr));
spin_unlock_bh(&session->lock);
iscsi_start_tx(conn);
goto success_unlocked;
case TMF_TIMEDOUT:
spin_unlock_bh(&session->lock);
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
goto failed_unlocked;
case TMF_NOT_FOUND:
if (!sc->SCp.ptr) {
conn->tmf_state = TMF_INITIAL;
memset(hdr, 0, sizeof(*hdr));
/* task completed before tmf abort response */
ISCSI_DBG_EH(session, "sc completed while abort in "
"progress\n");
goto success;
}
/* fall through */
default:
conn->tmf_state = TMF_INITIAL;
goto failed;
}
success:
spin_unlock_bh(&session->lock);
success_unlocked:
ISCSI_DBG_EH(session, "abort success [sc %p itt 0x%x]\n",
sc, task->itt);
mutex_unlock(&session->eh_mutex);
return SUCCESS;
failed:
spin_unlock_bh(&session->lock);
failed_unlocked:
ISCSI_DBG_EH(session, "abort failed [sc %p itt 0x%x]\n", sc,
task ? task->itt : 0);
mutex_unlock(&session->eh_mutex);
return FAILED;
}
EXPORT_SYMBOL_GPL(iscsi_eh_abort);
static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
{
memset(hdr, 0, sizeof(*hdr));
hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
hdr->flags |= ISCSI_FLAG_CMD_FINAL;
int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
hdr->rtt = RESERVED_ITT;
}
int iscsi_eh_device_reset(struct scsi_cmnd *sc)
{
struct iscsi_cls_session *cls_session;
struct iscsi_session *session;
struct iscsi_conn *conn;
struct iscsi_tm *hdr;
int rc = FAILED;
cls_session = starget_to_session(scsi_target(sc->device));
session = cls_session->dd_data;
ISCSI_DBG_EH(session, "LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
mutex_lock(&session->eh_mutex);
spin_lock_bh(&session->lock);
/*
* Just check if we are not logged in. We cannot check for
* the phase because the reset could come from a ioctl.
*/
if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
goto unlock;
conn = session->leadconn;
/* only have one tmf outstanding at a time */
if (conn->tmf_state != TMF_INITIAL)
goto unlock;
conn->tmf_state = TMF_QUEUED;
hdr = &conn->tmhdr;
iscsi_prep_lun_reset_pdu(sc, hdr);
if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
session->lu_reset_timeout)) {
rc = FAILED;
goto unlock;
}
switch (conn->tmf_state) {
case TMF_SUCCESS:
break;
case TMF_TIMEDOUT:
spin_unlock_bh(&session->lock);
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
goto done;
default:
conn->tmf_state = TMF_INITIAL;
goto unlock;
}
rc = SUCCESS;
spin_unlock_bh(&session->lock);
iscsi_suspend_tx(conn);
spin_lock_bh(&session->lock);
memset(hdr, 0, sizeof(*hdr));
fail_scsi_tasks(conn, sc->device->lun, DID_ERROR);
conn->tmf_state = TMF_INITIAL;
spin_unlock_bh(&session->lock);
iscsi_start_tx(conn);
goto done;
unlock:
spin_unlock_bh(&session->lock);
done:
ISCSI_DBG_EH(session, "dev reset result = %s\n",
rc == SUCCESS ? "SUCCESS" : "FAILED");
mutex_unlock(&session->eh_mutex);
return rc;
}
EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
{
struct iscsi_session *session = cls_session->dd_data;
spin_lock_bh(&session->lock);
if (session->state != ISCSI_STATE_LOGGED_IN) {
session->state = ISCSI_STATE_RECOVERY_FAILED;
if (session->leadconn)
wake_up(&session->leadconn->ehwait);
}
spin_unlock_bh(&session->lock);
}
EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
/**
* iscsi_eh_session_reset - drop session and attempt relogin
* @sc: scsi command
*
* This function will wait for a relogin, session termination from
* userspace, or a recovery/replacement timeout.
*/
static int iscsi_eh_session_reset(struct scsi_cmnd *sc)
{
struct iscsi_cls_session *cls_session;
struct iscsi_session *session;
struct iscsi_conn *conn;
cls_session = starget_to_session(scsi_target(sc->device));
session = cls_session->dd_data;
conn = session->leadconn;
mutex_lock(&session->eh_mutex);
spin_lock_bh(&session->lock);
if (session->state == ISCSI_STATE_TERMINATE) {
failed:
ISCSI_DBG_EH(session,
"failing session reset: Could not log back into "
"%s, %s [age %d]\n", session->targetname,
conn->persistent_address, session->age);
spin_unlock_bh(&session->lock);
mutex_unlock(&session->eh_mutex);
return FAILED;
}
spin_unlock_bh(&session->lock);
mutex_unlock(&session->eh_mutex);
/*
* we drop the lock here but the leadconn cannot be destoyed while
* we are in the scsi eh
*/
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
ISCSI_DBG_EH(session, "wait for relogin\n");
wait_event_interruptible(conn->ehwait,
session->state == ISCSI_STATE_TERMINATE ||
session->state == ISCSI_STATE_LOGGED_IN ||
session->state == ISCSI_STATE_RECOVERY_FAILED);
if (signal_pending(current))
flush_signals(current);
mutex_lock(&session->eh_mutex);
spin_lock_bh(&session->lock);
if (session->state == ISCSI_STATE_LOGGED_IN) {
ISCSI_DBG_EH(session,
"session reset succeeded for %s,%s\n",
session->targetname, conn->persistent_address);
} else
goto failed;
spin_unlock_bh(&session->lock);
mutex_unlock(&session->eh_mutex);
return SUCCESS;
}
static void iscsi_prep_tgt_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
{
memset(hdr, 0, sizeof(*hdr));
hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
hdr->flags = ISCSI_TM_FUNC_TARGET_WARM_RESET & ISCSI_FLAG_TM_FUNC_MASK;
hdr->flags |= ISCSI_FLAG_CMD_FINAL;
hdr->rtt = RESERVED_ITT;
}
/**
* iscsi_eh_target_reset - reset target
* @sc: scsi command
*
* This will attempt to send a warm target reset. If that fails
* then we will drop the session and attempt ERL0 recovery.
*/
int iscsi_eh_target_reset(struct scsi_cmnd *sc)
{
struct iscsi_cls_session *cls_session;
struct iscsi_session *session;
struct iscsi_conn *conn;
struct iscsi_tm *hdr;
int rc = FAILED;
cls_session = starget_to_session(scsi_target(sc->device));
session = cls_session->dd_data;
ISCSI_DBG_EH(session, "tgt Reset [sc %p tgt %s]\n", sc,
session->targetname);
mutex_lock(&session->eh_mutex);
spin_lock_bh(&session->lock);
/*
* Just check if we are not logged in. We cannot check for
* the phase because the reset could come from a ioctl.
*/
if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
goto unlock;
conn = session->leadconn;
/* only have one tmf outstanding at a time */
if (conn->tmf_state != TMF_INITIAL)
goto unlock;
conn->tmf_state = TMF_QUEUED;
hdr = &conn->tmhdr;
iscsi_prep_tgt_reset_pdu(sc, hdr);
if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
session->tgt_reset_timeout)) {
rc = FAILED;
goto unlock;
}
switch (conn->tmf_state) {
case TMF_SUCCESS:
break;
case TMF_TIMEDOUT:
spin_unlock_bh(&session->lock);
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
goto done;
default:
conn->tmf_state = TMF_INITIAL;
goto unlock;
}
rc = SUCCESS;
spin_unlock_bh(&session->lock);
iscsi_suspend_tx(conn);
spin_lock_bh(&session->lock);
memset(hdr, 0, sizeof(*hdr));
fail_scsi_tasks(conn, -1, DID_ERROR);
conn->tmf_state = TMF_INITIAL;
spin_unlock_bh(&session->lock);
iscsi_start_tx(conn);
goto done;
unlock:
spin_unlock_bh(&session->lock);
done:
ISCSI_DBG_EH(session, "tgt %s reset result = %s\n", session->targetname,
rc == SUCCESS ? "SUCCESS" : "FAILED");
mutex_unlock(&session->eh_mutex);
if (rc == FAILED)
rc = iscsi_eh_session_reset(sc);
return rc;
}
EXPORT_SYMBOL_GPL(iscsi_eh_target_reset);
/*
* Pre-allocate a pool of @max items of @item_size. By default, the pool
* should be accessed via kfifo_{get,put} on q->queue.
* Optionally, the caller can obtain the array of object pointers
* by passing in a non-NULL @items pointer
*/
int
iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
{
int i, num_arrays = 1;
memset(q, 0, sizeof(*q));
q->max = max;
/* If the user passed an items pointer, he wants a copy of
* the array. */
if (items)
num_arrays++;
q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
if (q->pool == NULL)
return -ENOMEM;
kfifo_init(&q->queue, (void*)q->pool, max * sizeof(void*));
for (i = 0; i < max; i++) {
q->pool[i] = kzalloc(item_size, GFP_KERNEL);
if (q->pool[i] == NULL) {
q->max = i;
goto enomem;
}
kfifo_in(&q->queue, (void*)&q->pool[i], sizeof(void*));
}
if (items) {
*items = q->pool + max;
memcpy(*items, q->pool, max * sizeof(void *));
}
return 0;
enomem:
iscsi_pool_free(q);
return -ENOMEM;
}
EXPORT_SYMBOL_GPL(iscsi_pool_init);
void iscsi_pool_free(struct iscsi_pool *q)
{
int i;
for (i = 0; i < q->max; i++)
kfree(q->pool[i]);
kfree(q->pool);
}
EXPORT_SYMBOL_GPL(iscsi_pool_free);
/**
* iscsi_host_add - add host to system
* @shost: scsi host
* @pdev: parent device
*
* This should be called by partial offload and software iscsi drivers
* to add a host to the system.
*/
int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev)
{
if (!shost->can_queue)
shost->can_queue = ISCSI_DEF_XMIT_CMDS_MAX;
if (!shost->cmd_per_lun)
shost->cmd_per_lun = ISCSI_DEF_CMD_PER_LUN;
if (!shost->transportt->eh_timed_out)
shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
return scsi_add_host(shost, pdev);
}
EXPORT_SYMBOL_GPL(iscsi_host_add);
/**
* iscsi_host_alloc - allocate a host and driver data
* @sht: scsi host template
* @dd_data_size: driver host data size
* @xmit_can_sleep: bool indicating if LLD will queue IO from a work queue
*
* This should be called by partial offload and software iscsi drivers.
* To access the driver specific memory use the iscsi_host_priv() macro.
*/
struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
int dd_data_size, bool xmit_can_sleep)
{
struct Scsi_Host *shost;
struct iscsi_host *ihost;
shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) + dd_data_size);
if (!shost)
return NULL;
ihost = shost_priv(shost);
if (xmit_can_sleep) {
snprintf(ihost->workq_name, sizeof(ihost->workq_name),
"iscsi_q_%d", shost->host_no);
ihost->workq = create_singlethread_workqueue(ihost->workq_name);
if (!ihost->workq)
goto free_host;
}
spin_lock_init(&ihost->lock);
ihost->state = ISCSI_HOST_SETUP;
ihost->num_sessions = 0;
init_waitqueue_head(&ihost->session_removal_wq);
return shost;
free_host:
scsi_host_put(shost);
return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_host_alloc);
static void iscsi_notify_host_removed(struct iscsi_cls_session *cls_session)
{
iscsi_session_failure(cls_session->dd_data, ISCSI_ERR_INVALID_HOST);
}
/**
* iscsi_host_remove - remove host and sessions
* @shost: scsi host
*
* If there are any sessions left, this will initiate the removal and wait
* for the completion.
*/
void iscsi_host_remove(struct Scsi_Host *shost)
{
struct iscsi_host *ihost = shost_priv(shost);
unsigned long flags;
spin_lock_irqsave(&ihost->lock, flags);
ihost->state = ISCSI_HOST_REMOVED;
spin_unlock_irqrestore(&ihost->lock, flags);
iscsi_host_for_each_session(shost, iscsi_notify_host_removed);
wait_event_interruptible(ihost->session_removal_wq,
ihost->num_sessions == 0);
if (signal_pending(current))
flush_signals(current);
scsi_remove_host(shost);
if (ihost->workq)
destroy_workqueue(ihost->workq);
}
EXPORT_SYMBOL_GPL(iscsi_host_remove);
void iscsi_host_free(struct Scsi_Host *shost)
{
struct iscsi_host *ihost = shost_priv(shost);
kfree(ihost->netdev);
kfree(ihost->hwaddress);
kfree(ihost->initiatorname);
scsi_host_put(shost);
}
EXPORT_SYMBOL_GPL(iscsi_host_free);
static void iscsi_host_dec_session_cnt(struct Scsi_Host *shost)
{
struct iscsi_host *ihost = shost_priv(shost);
unsigned long flags;
shost = scsi_host_get(shost);
if (!shost) {
printk(KERN_ERR "Invalid state. Cannot notify host removal "
"of session teardown event because host already "
"removed.\n");
return;
}
spin_lock_irqsave(&ihost->lock, flags);
ihost->num_sessions--;
if (ihost->num_sessions == 0)
wake_up(&ihost->session_removal_wq);
spin_unlock_irqrestore(&ihost->lock, flags);
scsi_host_put(shost);
}
/**
* iscsi_session_setup - create iscsi cls session and host and session
* @iscsit: iscsi transport template
* @shost: scsi host
* @cmds_max: session can queue
* @cmd_task_size: LLD task private data size
* @initial_cmdsn: initial CmdSN
*
* This can be used by software iscsi_transports that allocate
* a session per scsi host.
*
* Callers should set cmds_max to the largest total numer (mgmt + scsi) of
* tasks they support. The iscsi layer reserves ISCSI_MGMT_CMDS_MAX tasks
* for nop handling and login/logout requests.
*/
struct iscsi_cls_session *
iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
uint16_t cmds_max, int dd_size, int cmd_task_size,
uint32_t initial_cmdsn, unsigned int id)
{
struct iscsi_host *ihost = shost_priv(shost);
struct iscsi_session *session;
struct iscsi_cls_session *cls_session;
int cmd_i, scsi_cmds, total_cmds = cmds_max;
unsigned long flags;
spin_lock_irqsave(&ihost->lock, flags);
if (ihost->state == ISCSI_HOST_REMOVED) {
spin_unlock_irqrestore(&ihost->lock, flags);
return NULL;
}
ihost->num_sessions++;
spin_unlock_irqrestore(&ihost->lock, flags);
if (!total_cmds)
total_cmds = ISCSI_DEF_XMIT_CMDS_MAX;
/*
* The iscsi layer needs some tasks for nop handling and tmfs,
* so the cmds_max must at least be greater than ISCSI_MGMT_CMDS_MAX
* + 1 command for scsi IO.
*/
if (total_cmds < ISCSI_TOTAL_CMDS_MIN) {
printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
"must be a power of two that is at least %d.\n",
total_cmds, ISCSI_TOTAL_CMDS_MIN);
goto dec_session_count;
}
if (total_cmds > ISCSI_TOTAL_CMDS_MAX) {
printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
"must be a power of 2 less than or equal to %d.\n",
cmds_max, ISCSI_TOTAL_CMDS_MAX);
total_cmds = ISCSI_TOTAL_CMDS_MAX;
}
if (!is_power_of_2(total_cmds)) {
printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
"must be a power of 2.\n", total_cmds);
total_cmds = rounddown_pow_of_two(total_cmds);
if (total_cmds < ISCSI_TOTAL_CMDS_MIN)
return NULL;
printk(KERN_INFO "iscsi: Rounding can_queue to %d.\n",
total_cmds);
}
scsi_cmds = total_cmds - ISCSI_MGMT_CMDS_MAX;
cls_session = iscsi_alloc_session(shost, iscsit,
sizeof(struct iscsi_session) +
dd_size);
if (!cls_session)
goto dec_session_count;
session = cls_session->dd_data;
session->cls_session = cls_session;
session->host = shost;
session->state = ISCSI_STATE_FREE;
session->fast_abort = 1;
session->tgt_reset_timeout = 30;
session->lu_reset_timeout = 15;
session->abort_timeout = 10;
session->scsi_cmds_max = scsi_cmds;
session->cmds_max = total_cmds;
session->queued_cmdsn = session->cmdsn = initial_cmdsn;
session->exp_cmdsn = initial_cmdsn + 1;
session->max_cmdsn = initial_cmdsn + 1;
session->max_r2t = 1;
session->tt = iscsit;
session->dd_data = cls_session->dd_data + sizeof(*session);
mutex_init(&session->eh_mutex);
spin_lock_init(&session->lock);
/* initialize SCSI PDU commands pool */
if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
(void***)&session->cmds,
cmd_task_size + sizeof(struct iscsi_task)))
goto cmdpool_alloc_fail;
/* pre-format cmds pool with ITT */
for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
struct iscsi_task *task = session->cmds[cmd_i];
if (cmd_task_size)
task->dd_data = &task[1];
task->itt = cmd_i;
task->state = ISCSI_TASK_FREE;
INIT_LIST_HEAD(&task->running);
}
if (!try_module_get(iscsit->owner))
goto module_get_fail;
if (iscsi_add_session(cls_session, id))
goto cls_session_fail;
return cls_session;
cls_session_fail:
module_put(iscsit->owner);
module_get_fail:
iscsi_pool_free(&session->cmdpool);
cmdpool_alloc_fail:
iscsi_free_session(cls_session);
dec_session_count:
iscsi_host_dec_session_cnt(shost);
return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_session_setup);
/**
* iscsi_session_teardown - destroy session, host, and cls_session
* @cls_session: iscsi session
*
* The driver must have called iscsi_remove_session before
* calling this.
*/
void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
{
struct iscsi_session *session = cls_session->dd_data;
struct module *owner = cls_session->transport->owner;
struct Scsi_Host *shost = session->host;
iscsi_pool_free(&session->cmdpool);
kfree(session->password);
kfree(session->password_in);
kfree(session->username);
kfree(session->username_in);
kfree(session->targetname);
kfree(session->initiatorname);
kfree(session->ifacename);
iscsi_destroy_session(cls_session);
iscsi_host_dec_session_cnt(shost);
module_put(owner);
}
EXPORT_SYMBOL_GPL(iscsi_session_teardown);
/**
* iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
* @cls_session: iscsi_cls_session
* @dd_size: private driver data size
* @conn_idx: cid
*/
struct iscsi_cls_conn *
iscsi_conn_setup(struct iscsi_cls_session *cls_session, int dd_size,
uint32_t conn_idx)
{
struct iscsi_session *session = cls_session->dd_data;
struct iscsi_conn *conn;
struct iscsi_cls_conn *cls_conn;
char *data;
cls_conn = iscsi_create_conn(cls_session, sizeof(*conn) + dd_size,
conn_idx);
if (!cls_conn)
return NULL;
conn = cls_conn->dd_data;
memset(conn, 0, sizeof(*conn) + dd_size);
conn->dd_data = cls_conn->dd_data + sizeof(*conn);
conn->session = session;
conn->cls_conn = cls_conn;
conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
conn->id = conn_idx;
conn->exp_statsn = 0;
conn->tmf_state = TMF_INITIAL;
init_timer(&conn->transport_timer);
conn->transport_timer.data = (unsigned long)conn;
conn->transport_timer.function = iscsi_check_transport_timeouts;
INIT_LIST_HEAD(&conn->mgmtqueue);
INIT_LIST_HEAD(&conn->cmdqueue);
INIT_LIST_HEAD(&conn->requeue);
INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
/* allocate login_task used for the login/text sequences */
spin_lock_bh(&session->lock);
if (!kfifo_out(&session->cmdpool.queue,
(void*)&conn->login_task,
sizeof(void*))) {
spin_unlock_bh(&session->lock);
goto login_task_alloc_fail;
}
spin_unlock_bh(&session->lock);
data = (char *) __get_free_pages(GFP_KERNEL,
get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
if (!data)
goto login_task_data_alloc_fail;
conn->login_task->data = conn->data = data;
init_timer(&conn->tmf_timer);
init_waitqueue_head(&conn->ehwait);
return cls_conn;
login_task_data_alloc_fail:
kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
sizeof(void*));
login_task_alloc_fail:
iscsi_destroy_conn(cls_conn);
return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_conn_setup);
/**
* iscsi_conn_teardown - teardown iscsi connection
* cls_conn: iscsi class connection
*
* TODO: we may need to make this into a two step process
* like scsi-mls remove + put host
*/
void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_session *session = conn->session;
unsigned long flags;
del_timer_sync(&conn->transport_timer);
spin_lock_bh(&session->lock);
conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
if (session->leadconn == conn) {
/*
* leading connection? then give up on recovery.
*/
session->state = ISCSI_STATE_TERMINATE;
wake_up(&conn->ehwait);
}
spin_unlock_bh(&session->lock);
/*
* Block until all in-progress commands for this connection
* time out or fail.
*/
for (;;) {
spin_lock_irqsave(session->host->host_lock, flags);
if (!session->host->host_busy) { /* OK for ERL == 0 */
spin_unlock_irqrestore(session->host->host_lock, flags);
break;
}
spin_unlock_irqrestore(session->host->host_lock, flags);
msleep_interruptible(500);
iscsi_conn_printk(KERN_INFO, conn, "iscsi conn_destroy(): "
"host_busy %d host_failed %d\n",
session->host->host_busy,
session->host->host_failed);
/*
* force eh_abort() to unblock
*/
wake_up(&conn->ehwait);
}
/* flush queued up work because we free the connection below */
iscsi_suspend_tx(conn);
spin_lock_bh(&session->lock);
free_pages((unsigned long) conn->data,
get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
kfree(conn->persistent_address);
kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
sizeof(void*));
if (session->leadconn == conn)
session->leadconn = NULL;
spin_unlock_bh(&session->lock);
iscsi_destroy_conn(cls_conn);
}
EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_session *session = conn->session;
if (!session) {
iscsi_conn_printk(KERN_ERR, conn,
"can't start unbound connection\n");
return -EPERM;
}
if ((session->imm_data_en || !session->initial_r2t_en) &&
session->first_burst > session->max_burst) {
iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
"first_burst %d max_burst %d\n",
session->first_burst, session->max_burst);
return -EINVAL;
}
if (conn->ping_timeout && !conn->recv_timeout) {
iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
"zero. Using 5 seconds\n.");
conn->recv_timeout = 5;
}
if (conn->recv_timeout && !conn->ping_timeout) {
iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
"zero. Using 5 seconds.\n");
conn->ping_timeout = 5;
}
spin_lock_bh(&session->lock);
conn->c_stage = ISCSI_CONN_STARTED;
session->state = ISCSI_STATE_LOGGED_IN;
session->queued_cmdsn = session->cmdsn;
conn->last_recv = jiffies;
conn->last_ping = jiffies;
if (conn->recv_timeout && conn->ping_timeout)
mod_timer(&conn->transport_timer,
jiffies + (conn->recv_timeout * HZ));
switch(conn->stop_stage) {
case STOP_CONN_RECOVER:
/*
* unblock eh_abort() if it is blocked. re-try all
* commands after successful recovery
*/
conn->stop_stage = 0;
conn->tmf_state = TMF_INITIAL;
session->age++;
if (session->age == 16)
session->age = 0;
break;
case STOP_CONN_TERM:
conn->stop_stage = 0;
break;
default:
break;
}
spin_unlock_bh(&session->lock);
iscsi_unblock_session(session->cls_session);
wake_up(&conn->ehwait);
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_conn_start);
static void
fail_mgmt_tasks(struct iscsi_session *session, struct iscsi_conn *conn)
{
struct iscsi_task *task;
int i, state;
for (i = 0; i < conn->session->cmds_max; i++) {
task = conn->session->cmds[i];
if (task->sc)
continue;
if (task->state == ISCSI_TASK_FREE)
continue;
ISCSI_DBG_SESSION(conn->session,
"failing mgmt itt 0x%x state %d\n",
task->itt, task->state);
state = ISCSI_TASK_ABRT_SESS_RECOV;
if (task->state == ISCSI_TASK_PENDING)
state = ISCSI_TASK_COMPLETED;
iscsi_complete_task(task, state);
}
}
static void iscsi_start_session_recovery(struct iscsi_session *session,
struct iscsi_conn *conn, int flag)
{
int old_stop_stage;
mutex_lock(&session->eh_mutex);
spin_lock_bh(&session->lock);
if (conn->stop_stage == STOP_CONN_TERM) {
spin_unlock_bh(&session->lock);
mutex_unlock(&session->eh_mutex);
return;
}
/*
* When this is called for the in_login state, we only want to clean
* up the login task and connection. We do not need to block and set
* the recovery state again
*/
if (flag == STOP_CONN_TERM)
session->state = ISCSI_STATE_TERMINATE;
else if (conn->stop_stage != STOP_CONN_RECOVER)
session->state = ISCSI_STATE_IN_RECOVERY;
spin_unlock_bh(&session->lock);
del_timer_sync(&conn->transport_timer);
iscsi_suspend_tx(conn);
spin_lock_bh(&session->lock);
old_stop_stage = conn->stop_stage;
conn->stop_stage = flag;
conn->c_stage = ISCSI_CONN_STOPPED;
spin_unlock_bh(&session->lock);
/*
* for connection level recovery we should not calculate
* header digest. conn->hdr_size used for optimization
* in hdr_extract() and will be re-negotiated at
* set_param() time.
*/
if (flag == STOP_CONN_RECOVER) {
conn->hdrdgst_en = 0;
conn->datadgst_en = 0;
if (session->state == ISCSI_STATE_IN_RECOVERY &&
old_stop_stage != STOP_CONN_RECOVER) {
ISCSI_DBG_SESSION(session, "blocking session\n");
iscsi_block_session(session->cls_session);
}
}
/*
* flush queues.
*/
spin_lock_bh(&session->lock);
fail_scsi_tasks(conn, -1, DID_TRANSPORT_DISRUPTED);
fail_mgmt_tasks(session, conn);
memset(&conn->tmhdr, 0, sizeof(conn->tmhdr));
spin_unlock_bh(&session->lock);
mutex_unlock(&session->eh_mutex);
}
void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_session *session = conn->session;
switch (flag) {
case STOP_CONN_RECOVER:
case STOP_CONN_TERM:
iscsi_start_session_recovery(session, conn, flag);
break;
default:
iscsi_conn_printk(KERN_ERR, conn,
"invalid stop flag %d\n", flag);
}
}
EXPORT_SYMBOL_GPL(iscsi_conn_stop);
int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
struct iscsi_cls_conn *cls_conn, int is_leading)
{
struct iscsi_session *session = cls_session->dd_data;
struct iscsi_conn *conn = cls_conn->dd_data;
spin_lock_bh(&session->lock);
if (is_leading)
session->leadconn = conn;
spin_unlock_bh(&session->lock);
/*
* Unblock xmitworker(), Login Phase will pass through.
*/
clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_conn_bind);
static int iscsi_switch_str_param(char **param, char *new_val_buf)
{
char *new_val;
if (*param) {
if (!strcmp(*param, new_val_buf))
return 0;
}
new_val = kstrdup(new_val_buf, GFP_NOIO);
if (!new_val)
return -ENOMEM;
kfree(*param);
*param = new_val;
return 0;
}
int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
enum iscsi_param param, char *buf, int buflen)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_session *session = conn->session;
uint32_t value;
switch(param) {
case ISCSI_PARAM_FAST_ABORT:
sscanf(buf, "%d", &session->fast_abort);
break;
case ISCSI_PARAM_ABORT_TMO:
sscanf(buf, "%d", &session->abort_timeout);
break;
case ISCSI_PARAM_LU_RESET_TMO:
sscanf(buf, "%d", &session->lu_reset_timeout);
break;
case ISCSI_PARAM_TGT_RESET_TMO:
sscanf(buf, "%d", &session->tgt_reset_timeout);
break;
case ISCSI_PARAM_PING_TMO:
sscanf(buf, "%d", &conn->ping_timeout);
break;
case ISCSI_PARAM_RECV_TMO:
sscanf(buf, "%d", &conn->recv_timeout);
break;
case ISCSI_PARAM_MAX_RECV_DLENGTH:
sscanf(buf, "%d", &conn->max_recv_dlength);
break;
case ISCSI_PARAM_MAX_XMIT_DLENGTH:
sscanf(buf, "%d", &conn->max_xmit_dlength);
break;
case ISCSI_PARAM_HDRDGST_EN:
sscanf(buf, "%d", &conn->hdrdgst_en);
break;
case ISCSI_PARAM_DATADGST_EN:
sscanf(buf, "%d", &conn->datadgst_en);
break;
case ISCSI_PARAM_INITIAL_R2T_EN:
sscanf(buf, "%d", &session->initial_r2t_en);
break;
case ISCSI_PARAM_MAX_R2T:
sscanf(buf, "%d", &session->max_r2t);
break;
case ISCSI_PARAM_IMM_DATA_EN:
sscanf(buf, "%d", &session->imm_data_en);
break;
case ISCSI_PARAM_FIRST_BURST:
sscanf(buf, "%d", &session->first_burst);
break;
case ISCSI_PARAM_MAX_BURST:
sscanf(buf, "%d", &session->max_burst);
break;
case ISCSI_PARAM_PDU_INORDER_EN:
sscanf(buf, "%d", &session->pdu_inorder_en);
break;
case ISCSI_PARAM_DATASEQ_INORDER_EN:
sscanf(buf, "%d", &session->dataseq_inorder_en);
break;
case ISCSI_PARAM_ERL:
sscanf(buf, "%d", &session->erl);
break;
case ISCSI_PARAM_IFMARKER_EN:
sscanf(buf, "%d", &value);
BUG_ON(value);
break;
case ISCSI_PARAM_OFMARKER_EN:
sscanf(buf, "%d", &value);
BUG_ON(value);
break;
case ISCSI_PARAM_EXP_STATSN:
sscanf(buf, "%u", &conn->exp_statsn);
break;
case ISCSI_PARAM_USERNAME:
return iscsi_switch_str_param(&session->username, buf);
case ISCSI_PARAM_USERNAME_IN:
return iscsi_switch_str_param(&session->username_in, buf);
case ISCSI_PARAM_PASSWORD:
return iscsi_switch_str_param(&session->password, buf);
case ISCSI_PARAM_PASSWORD_IN:
return iscsi_switch_str_param(&session->password_in, buf);
case ISCSI_PARAM_TARGET_NAME:
return iscsi_switch_str_param(&session->targetname, buf);
case ISCSI_PARAM_TPGT:
sscanf(buf, "%d", &session->tpgt);
break;
case ISCSI_PARAM_PERSISTENT_PORT:
sscanf(buf, "%d", &conn->persistent_port);
break;
case ISCSI_PARAM_PERSISTENT_ADDRESS:
return iscsi_switch_str_param(&conn->persistent_address, buf);
case ISCSI_PARAM_IFACE_NAME:
return iscsi_switch_str_param(&session->ifacename, buf);
case ISCSI_PARAM_INITIATOR_NAME:
return iscsi_switch_str_param(&session->initiatorname, buf);
default:
return -ENOSYS;
}
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_set_param);
int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
enum iscsi_param param, char *buf)
{
struct iscsi_session *session = cls_session->dd_data;
int len;
switch(param) {
case ISCSI_PARAM_FAST_ABORT:
len = sprintf(buf, "%d\n", session->fast_abort);
break;
case ISCSI_PARAM_ABORT_TMO:
len = sprintf(buf, "%d\n", session->abort_timeout);
break;
case ISCSI_PARAM_LU_RESET_TMO:
len = sprintf(buf, "%d\n", session->lu_reset_timeout);
break;
case ISCSI_PARAM_TGT_RESET_TMO:
len = sprintf(buf, "%d\n", session->tgt_reset_timeout);
break;
case ISCSI_PARAM_INITIAL_R2T_EN:
len = sprintf(buf, "%d\n", session->initial_r2t_en);
break;
case ISCSI_PARAM_MAX_R2T:
len = sprintf(buf, "%hu\n", session->max_r2t);
break;
case ISCSI_PARAM_IMM_DATA_EN:
len = sprintf(buf, "%d\n", session->imm_data_en);
break;
case ISCSI_PARAM_FIRST_BURST:
len = sprintf(buf, "%u\n", session->first_burst);
break;
case ISCSI_PARAM_MAX_BURST:
len = sprintf(buf, "%u\n", session->max_burst);
break;
case ISCSI_PARAM_PDU_INORDER_EN:
len = sprintf(buf, "%d\n", session->pdu_inorder_en);
break;
case ISCSI_PARAM_DATASEQ_INORDER_EN:
len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
break;
case ISCSI_PARAM_ERL:
len = sprintf(buf, "%d\n", session->erl);
break;
case ISCSI_PARAM_TARGET_NAME:
len = sprintf(buf, "%s\n", session->targetname);
break;
case ISCSI_PARAM_TPGT:
len = sprintf(buf, "%d\n", session->tpgt);
break;
case ISCSI_PARAM_USERNAME:
len = sprintf(buf, "%s\n", session->username);
break;
case ISCSI_PARAM_USERNAME_IN:
len = sprintf(buf, "%s\n", session->username_in);
break;
case ISCSI_PARAM_PASSWORD:
len = sprintf(buf, "%s\n", session->password);
break;
case ISCSI_PARAM_PASSWORD_IN:
len = sprintf(buf, "%s\n", session->password_in);
break;
case ISCSI_PARAM_IFACE_NAME:
len = sprintf(buf, "%s\n", session->ifacename);
break;
case ISCSI_PARAM_INITIATOR_NAME:
len = sprintf(buf, "%s\n", session->initiatorname);
break;
default:
return -ENOSYS;
}
return len;
}
EXPORT_SYMBOL_GPL(iscsi_session_get_param);
int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
enum iscsi_param param, char *buf)
{
struct iscsi_conn *conn = cls_conn->dd_data;
int len;
switch(param) {
case ISCSI_PARAM_PING_TMO:
len = sprintf(buf, "%u\n", conn->ping_timeout);
break;
case ISCSI_PARAM_RECV_TMO:
len = sprintf(buf, "%u\n", conn->recv_timeout);
break;
case ISCSI_PARAM_MAX_RECV_DLENGTH:
len = sprintf(buf, "%u\n", conn->max_recv_dlength);
break;
case ISCSI_PARAM_MAX_XMIT_DLENGTH:
len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
break;
case ISCSI_PARAM_HDRDGST_EN:
len = sprintf(buf, "%d\n", conn->hdrdgst_en);
break;
case ISCSI_PARAM_DATADGST_EN:
len = sprintf(buf, "%d\n", conn->datadgst_en);
break;
case ISCSI_PARAM_IFMARKER_EN:
len = sprintf(buf, "%d\n", conn->ifmarker_en);
break;
case ISCSI_PARAM_OFMARKER_EN:
len = sprintf(buf, "%d\n", conn->ofmarker_en);
break;
case ISCSI_PARAM_EXP_STATSN:
len = sprintf(buf, "%u\n", conn->exp_statsn);
break;
case ISCSI_PARAM_PERSISTENT_PORT:
len = sprintf(buf, "%d\n", conn->persistent_port);
break;
case ISCSI_PARAM_PERSISTENT_ADDRESS:
len = sprintf(buf, "%s\n", conn->persistent_address);
break;
default:
return -ENOSYS;
}
return len;
}
EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
char *buf)
{
struct iscsi_host *ihost = shost_priv(shost);
int len;
switch (param) {
case ISCSI_HOST_PARAM_NETDEV_NAME:
len = sprintf(buf, "%s\n", ihost->netdev);
break;
case ISCSI_HOST_PARAM_HWADDRESS:
len = sprintf(buf, "%s\n", ihost->hwaddress);
break;
case ISCSI_HOST_PARAM_INITIATOR_NAME:
len = sprintf(buf, "%s\n", ihost->initiatorname);
break;
case ISCSI_HOST_PARAM_IPADDRESS:
len = sprintf(buf, "%s\n", ihost->local_address);
break;
default:
return -ENOSYS;
}
return len;
}
EXPORT_SYMBOL_GPL(iscsi_host_get_param);
int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
char *buf, int buflen)
{
struct iscsi_host *ihost = shost_priv(shost);
switch (param) {
case ISCSI_HOST_PARAM_NETDEV_NAME:
return iscsi_switch_str_param(&ihost->netdev, buf);
case ISCSI_HOST_PARAM_HWADDRESS:
return iscsi_switch_str_param(&ihost->hwaddress, buf);
case ISCSI_HOST_PARAM_INITIATOR_NAME:
return iscsi_switch_str_param(&ihost->initiatorname, buf);
default:
return -ENOSYS;
}
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_host_set_param);
MODULE_AUTHOR("Mike Christie");
MODULE_DESCRIPTION("iSCSI library functions");
MODULE_LICENSE("GPL");
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