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edbc9aa058
linux/drivers/scsi/libiscsi.c
Mike Christie edbc9aa058 [SCSI] libiscsi: have iscsi_data_in_rsp call iscsi_update_cmdsn 
This has iscsi_data_in_rsp call iscsi_update_cmdsn when a pdu is
completed like is done for other pdu's that are don.

For libiscsi_tcp, this means that it calls iscsi_update_cmdsn when
it is handling the pdu internally to only transfer data, but if there is
status then it does not need to call it since the completion handling
will do it.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-05-23 15:44:10 -05:00

2949 lines
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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;
module_param_named(debug_libiscsi, iscsi_dbg_lib, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug_libiscsi, "Turn on debugging for 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) \
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) \
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);
queue_work(ihost->workq, &conn->xmitwork);
}
EXPORT_SYMBOL_GPL(iscsi_conn_queue_work);
void
iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
{
uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_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->xmitqueue) ||
!list_empty(&session->leadconn->mgmtqueue)) {
if (!(session->tt->caps & CAP_DATA_PATH_OFFLOAD))
iscsi_conn_queue_work(session->leadconn);
}
}
}
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_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;
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->cmdsn = task->cmdsn = cpu_to_be32(session->cmdsn);
session->cmdsn++;
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;
list_move_tail(&task->running, &conn->run_list);
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_complete_command - finish 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_complete_command(struct iscsi_task *task)
{
struct iscsi_conn *conn = task->conn;
struct iscsi_session *session = conn->session;
struct scsi_cmnd *sc = task->sc;
session->tt->cleanup_task(task);
list_del_init(&task->running);
task->state = ISCSI_TASK_COMPLETED;
task->sc = NULL;
if (conn->task == task)
conn->task = NULL;
/*
* login task is preallocated so do not free
*/
if (conn->login_task == task)
return;
__kfifo_put(session->cmdpool.queue, (void*)&task, sizeof(void*));
if (conn->ping_task == task)
conn->ping_task = NULL;
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_complete_command(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);
/*
* session lock must be held
*/
static void fail_command(struct iscsi_conn *conn, struct iscsi_task *task,
int err)
{
struct scsi_cmnd *sc;
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--;
sc->result = err;
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;
}
if (conn->task == task)
conn->task = NULL;
/* release ref from queuecommand */
__iscsi_put_task(task);
}
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;
if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
return -ENOTCONN;
if (hdr->opcode != (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) &&
hdr->opcode != (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
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, so we never hit this.
* If we start to send tmfs or nops as non-immediate then
* we should start checking the cmdsn numbers for mgmt tasks.
*/
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;
list_move_tail(&task->running, &conn->mgmt_run_list);
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_task *task;
itt_t itt;
if (session->state == ISCSI_STATE_TERMINATE)
return NULL;
if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
/*
* 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().
*/
task = conn->login_task;
else {
BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
if (!__kfifo_get(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;
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 requeue_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);
}
INIT_LIST_HEAD(&task->running);
list_add_tail(&task->running, &conn->mgmtqueue);
if (session->tt->caps & CAP_DATA_PATH_OFFLOAD) {
if (iscsi_prep_mgmt_task(conn, task))
goto free_task;
if (session->tt->xmit_task(task))
goto free_task;
} else
iscsi_conn_queue_work(conn);
return task;
free_task:
__iscsi_put_task(task);
return NULL;
requeue_task:
if (task != conn->login_task)
__kfifo_put(session->cmdpool.queue, (void*)&task,
sizeof(void*));
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, "done [sc %p res %d itt 0x%x]\n",
sc, sc->result, task->itt);
conn->scsirsp_pdus_cnt++;
__iscsi_put_task(task);
}
/**
* 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;
}
conn->scsirsp_pdus_cnt++;
__iscsi_put_task(task);
}
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_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;
conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
if (reject->reason == ISCSI_REASON_DATA_DIGEST_ERROR) {
if (ntoh24(reject->dlength) > datalen)
return ISCSI_ERR_PROTO;
if (ntoh24(reject->dlength) >= sizeof(struct iscsi_hdr)) {
memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
iscsi_conn_printk(KERN_ERR, conn,
"pdu (op 0x%x) rejected "
"due to DataDigest error.\n",
rejected_pdu.opcode);
}
}
return 0;
}
/**
* 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;
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_put_task(task);
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;
if (conn->ping_task != task)
/*
* If this is not in response to one of our
* nops then it must be from userspace.
*/
goto recv_pdu;
mod_timer(&conn->transport_timer, jiffies + conn->recv_timeout);
__iscsi_put_task(task);
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_put_task(task);
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;
__iscsi_get_task(task);
spin_unlock_bh(&conn->session->lock);
rc = conn->session->tt->xmit_task(task);
spin_lock_bh(&conn->session->lock);
__iscsi_put_task(task);
if (!rc)
/* done with this task */
conn->task = NULL;
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;
list_move_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)
{
int rc = 0;
spin_lock_bh(&conn->session->lock);
if (unlikely(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 again;
}
/*
* 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);
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 again;
}
/* process pending command queue */
while (!list_empty(&conn->xmitqueue)) {
if (conn->tmf_state == TMF_QUEUED)
break;
conn->task = list_entry(conn->xmitqueue.next,
struct iscsi_task, running);
if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
fail_command(conn, conn->task, DID_IMM_RETRY << 16);
continue;
}
rc = iscsi_prep_scsi_cmd_pdu(conn->task);
if (rc) {
if (rc == -ENOMEM) {
conn->task = NULL;
goto again;
} else
fail_command(conn, conn->task, DID_ABORT << 16);
continue;
}
rc = iscsi_xmit_task(conn);
if (rc)
goto again;
/*
* 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)) {
if (conn->session->fast_abort && conn->tmf_state != TMF_INITIAL)
break;
/*
* we always do fastlogout - conn stop code will clean up.
*/
if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
break;
conn->task = list_entry(conn->requeue.next,
struct iscsi_task, running);
conn->task->state = ISCSI_TASK_RUNNING;
list_move_tail(conn->requeue.next, &conn->run_list);
rc = iscsi_xmit_task(conn);
if (rc)
goto again;
if (!list_empty(&conn->mgmtqueue))
goto check_mgmt;
}
spin_unlock_bh(&conn->session->lock);
return -ENODATA;
again:
if (unlikely(conn->suspend_tx))
rc = -ENODATA;
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_get(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;
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;
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;
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;
}
/*
* ISCSI_STATE_FAILED is a temp. state. The recovery
* code will decide what is best to do with command queued
* during this time
*/
if (session->state != ISCSI_STATE_LOGGED_IN &&
session->state != ISCSI_STATE_FAILED) {
/*
* 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_IN_RECOVERY:
reason = FAILURE_SESSION_IN_RECOVERY;
goto reject;
case ISCSI_STATE_LOGGING_OUT:
reason = FAILURE_SESSION_LOGGING_OUT;
goto reject;
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 (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;
}
list_add_tail(&task->running, &conn->xmitqueue);
if (session->tt->caps & CAP_DATA_PATH_OFFLOAD) {
reason = iscsi_prep_scsi_cmd_pdu(task);
if (reason) {
if (reason == -ENOMEM) {
reason = FAILURE_OOM;
goto prepd_reject;
} else {
sc->result = DID_ABORT << 16;
goto prepd_fault;
}
}
if (session->tt->xmit_task(task)) {
reason = FAILURE_SESSION_NOT_READY;
goto prepd_reject;
}
} else
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_command(task);
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_command(task);
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)
{
scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
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);
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);
int iscsi_eh_target_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_session_printk(KERN_INFO, session,
"failing target reset: Could not log "
"back into target [age %d]\n",
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_SESSION(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_session_printk(KERN_INFO, session,
"target reset succeeded\n");
else
goto failed;
spin_unlock_bh(&session->lock);
mutex_unlock(&session->eh_mutex);
return SUCCESS;
}
EXPORT_SYMBOL_GPL(iscsi_eh_target_reset);
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_SESSION(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_SESSION(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_SESSION(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_all_commands(struct iscsi_conn *conn, unsigned lun,
int error)
{
struct iscsi_task *task, *tmp;
if (conn->task) {
if (lun == -1 ||
(conn->task->sc && conn->task->sc->device->lun == lun))
conn->task = NULL;
}
/* flush pending */
list_for_each_entry_safe(task, tmp, &conn->xmitqueue, running) {
if (lun == task->sc->device->lun || lun == -1) {
ISCSI_DBG_SESSION(conn->session,
"failing pending sc %p itt 0x%x\n",
task->sc, task->itt);
fail_command(conn, task, error << 16);
}
}
list_for_each_entry_safe(task, tmp, &conn->requeue, running) {
if (lun == task->sc->device->lun || lun == -1) {
ISCSI_DBG_SESSION(conn->session,
"failing requeued sc %p itt 0x%x\n",
task->sc, task->itt);
fail_command(conn, task, error << 16);
}
}
/* fail all other running */
list_for_each_entry_safe(task, tmp, &conn->run_list, running) {
if (lun == task->sc->device->lun || lun == -1) {
ISCSI_DBG_SESSION(conn->session,
"failing in progress sc %p itt 0x%x\n",
task->sc, task->itt);
fail_command(conn, task, error << 16);
}
}
}
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 (!(conn->session->tt->caps & CAP_DATA_PATH_OFFLOAD))
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);
if (!(conn->session->tt->caps & CAP_DATA_PATH_OFFLOAD))
iscsi_conn_queue_work(conn);
}
static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
{
struct iscsi_cls_session *cls_session;
struct iscsi_session *session;
struct iscsi_conn *conn;
enum blk_eh_timer_return rc = BLK_EH_NOT_HANDLED;
cls_session = starget_to_session(scsi_target(scmd->device));
session = cls_session->dd_data;
ISCSI_DBG_SESSION(session, "scsi cmd %p timedout\n", scmd);
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;
}
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 (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
(conn->ping_timeout * HZ), jiffies))
rc = BLK_EH_RESET_TIMER;
/*
* if we are about to check the transport then give the command
* more time
*/
if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ),
jiffies))
rc = BLK_EH_RESET_TIMER;
/* if in the middle of checking the transport then give us more time */
if (conn->ping_task)
rc = BLK_EH_RESET_TIMER;
done:
spin_unlock(&session->lock);
ISCSI_DBG_SESSION(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 (conn->ping_task &&
time_before_eq(conn->last_ping + (conn->ping_timeout * HZ),
jiffies)) {
iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
"expired, last rx %lu, last ping %lu, "
"now %lu\n", conn->ping_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;
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_SESSION(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);
return FAILED;
}
conn = session->leadconn;
conn->eh_abort_cnt++;
age = session->age;
task = (struct iscsi_task *)sc->SCp.ptr;
ISCSI_DBG_SESSION(session, "aborting [sc %p itt 0x%x]\n",
sc, task->itt);
/* task completed before time out */
if (!task->sc) {
ISCSI_DBG_SESSION(session, "sc completed while abort in "
"progress\n");
goto success;
}
if (task->state == ISCSI_TASK_PENDING) {
fail_command(conn, task, DID_ABORT << 16);
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(&session->lock);
fail_command(conn, task, DID_ABORT << 16);
conn->tmf_state = TMF_INITIAL;
spin_unlock(&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;
/* task completed before tmf abort response */
ISCSI_DBG_SESSION(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_SESSION(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_SESSION(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_SESSION(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);
fail_all_commands(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_SESSION(session, "dev reset result = %s\n",
rc == SUCCESS ? "SUCCESS" : "FAILED");
mutex_unlock(&session->eh_mutex);
return rc;
}
EXPORT_SYMBOL_GPL(iscsi_eh_device_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;
q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
GFP_KERNEL, NULL);
if (IS_ERR(q->queue)) {
q->queue = NULL;
goto enomem;
}
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_put(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);
kfree(q->queue);
}
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 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));
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->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;
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;
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->run_list);
INIT_LIST_HEAD(&conn->mgmt_run_list);
INIT_LIST_HEAD(&conn->mgmtqueue);
INIT_LIST_HEAD(&conn->xmitqueue);
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_get(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_put(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_put(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
flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
{
struct iscsi_task *task, *tmp;
/* handle pending */
list_for_each_entry_safe(task, tmp, &conn->mgmtqueue, running) {
ISCSI_DBG_SESSION(session, "flushing pending mgmt task "
"itt 0x%x\n", task->itt);
/* release ref from prep task */
__iscsi_put_task(task);
}
/* handle running */
list_for_each_entry_safe(task, tmp, &conn->mgmt_run_list, running) {
ISCSI_DBG_SESSION(session, "flushing running mgmt task "
"itt 0x%x\n", task->itt);
/* release ref from prep task */
__iscsi_put_task(task);
}
conn->task = NULL;
}
static void iscsi_start_session_recovery(struct iscsi_session *session,
struct iscsi_conn *conn, int flag)
{
int old_stop_stage;
del_timer_sync(&conn->transport_timer);
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;
old_stop_stage = conn->stop_stage;
conn->stop_stage = flag;
conn->c_stage = ISCSI_CONN_STOPPED;
spin_unlock_bh(&session->lock);
iscsi_suspend_tx(conn);
/*
* 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);
if (flag == STOP_CONN_RECOVER)
fail_all_commands(conn, -1, DID_TRANSPORT_DISRUPTED);
else
fail_all_commands(conn, -1, DID_ERROR);
flush_control_queues(session, conn);
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_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_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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