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linux/drivers/scsi/libiscsi.c
Mike Christie e648f63c65 [SCSI] libiscsi: don't call into lld to cleanup task 
In the normal IO path we should not be calling back
into the LLD since the LLD will have cleaned up the
task before or after calling complete pdu.

For the fail_command path we still need to do this
to force the cleanup.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-09-02 13:37:40 -05:00

1998 lines
53 KiB
C
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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/mutex.h>
#include <linux/kfifo.h>
#include <linux/delay.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>
struct iscsi_session *
class_to_transport_session(struct iscsi_cls_session *cls_session)
{
struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
return iscsi_hostdata(shost->hostdata);
}
EXPORT_SYMBOL_GPL(class_to_transport_session);
#define INVALID_SN_DELTA 0xffff
int
iscsi_check_assign_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);
if (max_cmdsn < exp_cmdsn -1 &&
max_cmdsn > exp_cmdsn - INVALID_SN_DELTA)
return ISCSI_ERR_MAX_CMDSN;
if (max_cmdsn > session->max_cmdsn ||
max_cmdsn < session->max_cmdsn - INVALID_SN_DELTA)
session->max_cmdsn = max_cmdsn;
if (exp_cmdsn > session->exp_cmdsn ||
exp_cmdsn < session->exp_cmdsn - INVALID_SN_DELTA)
session->exp_cmdsn = exp_cmdsn;
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_check_assign_cmdsn);
void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask,
struct iscsi_data *hdr)
{
struct iscsi_conn *conn = ctask->conn;
memset(hdr, 0, sizeof(struct iscsi_data));
hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
ctask->unsol_datasn++;
hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
hdr->itt = ctask->hdr->itt;
hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
hdr->offset = cpu_to_be32(ctask->unsol_offset);
if (ctask->unsol_count > conn->max_xmit_dlength) {
hton24(hdr->dlength, conn->max_xmit_dlength);
ctask->data_count = conn->max_xmit_dlength;
ctask->unsol_offset += ctask->data_count;
hdr->flags = 0;
} else {
hton24(hdr->dlength, ctask->unsol_count);
ctask->data_count = ctask->unsol_count;
hdr->flags = ISCSI_FLAG_CMD_FINAL;
}
}
EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
/**
* iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
* @ctask: iscsi cmd 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 void iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
{
struct iscsi_conn *conn = ctask->conn;
struct iscsi_session *session = conn->session;
struct iscsi_cmd *hdr = ctask->hdr;
struct scsi_cmnd *sc = ctask->sc;
hdr->opcode = ISCSI_OP_SCSI_CMD;
hdr->flags = ISCSI_ATTR_SIMPLE;
int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
hdr->itt = ctask->itt | (conn->id << ISCSI_CID_SHIFT) |
(session->age << ISCSI_AGE_SHIFT);
hdr->data_length = cpu_to_be32(sc->request_bufflen);
hdr->cmdsn = cpu_to_be32(session->cmdsn);
session->cmdsn++;
hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
memcpy(hdr->cdb, sc->cmnd, sc->cmd_len);
memset(&hdr->cdb[sc->cmd_len], 0, MAX_COMMAND_SIZE - sc->cmd_len);
ctask->data_count = 0;
if (sc->sc_data_direction == DMA_TO_DEVICE) {
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_count bytes to be sent via R2T ack's
*
* pad_count bytes to be sent as zero-padding
*/
ctask->imm_count = 0;
ctask->unsol_count = 0;
ctask->unsol_offset = 0;
ctask->unsol_datasn = 0;
if (session->imm_data_en) {
if (ctask->total_length >= session->first_burst)
ctask->imm_count = min(session->first_burst,
conn->max_xmit_dlength);
else
ctask->imm_count = min(ctask->total_length,
conn->max_xmit_dlength);
hton24(ctask->hdr->dlength, ctask->imm_count);
} else
zero_data(ctask->hdr->dlength);
if (!session->initial_r2t_en) {
ctask->unsol_count = min(session->first_burst,
ctask->total_length) - ctask->imm_count;
ctask->unsol_offset = ctask->imm_count;
}
if (!ctask->unsol_count)
/* No unsolicit Data-Out's */
ctask->hdr->flags |= ISCSI_FLAG_CMD_FINAL;
} else {
ctask->datasn = 0;
hdr->flags |= ISCSI_FLAG_CMD_FINAL;
zero_data(hdr->dlength);
if (sc->sc_data_direction == DMA_FROM_DEVICE)
hdr->flags |= ISCSI_FLAG_CMD_READ;
}
conn->scsicmd_pdus_cnt++;
}
EXPORT_SYMBOL_GPL(iscsi_prep_scsi_cmd_pdu);
/**
* iscsi_complete_command - return command back to scsi-ml
* @ctask: iscsi cmd task
*
* Must be called with session lock.
* This function returns the scsi command to scsi-ml and returns
* the cmd task to the pool of available cmd tasks.
*/
static void iscsi_complete_command(struct iscsi_cmd_task *ctask)
{
struct iscsi_session *session = ctask->conn->session;
struct scsi_cmnd *sc = ctask->sc;
ctask->state = ISCSI_TASK_COMPLETED;
ctask->sc = NULL;
/* SCSI eh reuses commands to verify us */
sc->SCp.ptr = NULL;
list_del_init(&ctask->running);
__kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
sc->scsi_done(sc);
}
static void __iscsi_get_ctask(struct iscsi_cmd_task *ctask)
{
atomic_inc(&ctask->refcount);
}
static void iscsi_get_ctask(struct iscsi_cmd_task *ctask)
{
spin_lock_bh(&ctask->conn->session->lock);
__iscsi_get_ctask(ctask);
spin_unlock_bh(&ctask->conn->session->lock);
}
static void __iscsi_put_ctask(struct iscsi_cmd_task *ctask)
{
if (atomic_dec_and_test(&ctask->refcount))
iscsi_complete_command(ctask);
}
static void iscsi_put_ctask(struct iscsi_cmd_task *ctask)
{
spin_lock_bh(&ctask->conn->session->lock);
__iscsi_put_ctask(ctask);
spin_unlock_bh(&ctask->conn->session->lock);
}
/**
* iscsi_cmd_rsp - SCSI Command Response processing
* @conn: iscsi connection
* @hdr: iscsi header
* @ctask: 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 int iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
struct iscsi_cmd_task *ctask, char *data,
int datalen)
{
int rc;
struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
struct iscsi_session *session = conn->session;
struct scsi_cmnd *sc = ctask->sc;
rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
if (rc) {
sc->result = DID_ERROR << 16;
goto out;
}
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) {
int senselen;
if (datalen < 2) {
invalid_datalen:
printk(KERN_ERR "iscsi: Got CHECK_CONDITION but "
"invalid data buffer size of %d\n", datalen);
sc->result = DID_BAD_TARGET << 16;
goto out;
}
senselen = (data[0] << 8) | data[1];
if (datalen < senselen)
goto invalid_datalen;
memcpy(sc->sense_buffer, data + 2,
min(senselen, SCSI_SENSE_BUFFERSIZE));
debug_scsi("copied %d bytes of sense\n",
min(senselen, SCSI_SENSE_BUFFERSIZE));
}
if (sc->sc_data_direction == DMA_TO_DEVICE)
goto out;
if (rhdr->flags & ISCSI_FLAG_CMD_UNDERFLOW) {
int res_count = be32_to_cpu(rhdr->residual_count);
if (res_count > 0 && res_count <= sc->request_bufflen)
sc->resid = res_count;
else
sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
} else if (rhdr->flags & ISCSI_FLAG_CMD_BIDI_UNDERFLOW)
sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
else if (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW)
sc->resid = be32_to_cpu(rhdr->residual_count);
out:
debug_scsi("done [sc %lx res %d itt 0x%x]\n",
(long)sc, sc->result, ctask->itt);
conn->scsirsp_pdus_cnt++;
__iscsi_put_ctask(ctask);
return rc;
}
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->tmabort_state != TMABORT_INITIAL)
return;
if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
conn->tmabort_state = TMABORT_SUCCESS;
else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
conn->tmabort_state = TMABORT_NOT_FOUND;
else
conn->tmabort_state = TMABORT_FAILED;
wake_up(&conn->ehwait);
}
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;
uint32_t itt;
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));
itt = rejected_pdu.itt & ISCSI_ITT_MASK;
printk(KERN_ERR "itt 0x%x had pdu (op 0x%x) rejected "
"due to DataDigest error.\n", itt,
rejected_pdu.opcode);
}
}
return 0;
}
/**
* __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_cmd_task *ctask;
struct iscsi_mgmt_task *mtask;
uint32_t itt;
if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG))
itt = hdr->itt & ISCSI_ITT_MASK;
else
itt = hdr->itt;
if (itt < session->cmds_max) {
ctask = session->cmds[itt];
debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
opcode, conn->id, ctask->itt, datalen);
switch(opcode) {
case ISCSI_OP_SCSI_CMD_RSP:
BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
rc = iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
datalen);
break;
case ISCSI_OP_SCSI_DATA_IN:
BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
conn->scsirsp_pdus_cnt++;
__iscsi_put_ctask(ctask);
}
break;
case ISCSI_OP_R2T:
/* LLD handles this for now */
break;
default:
rc = ISCSI_ERR_BAD_OPCODE;
break;
}
} else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
opcode, conn->id, mtask->itt, datalen);
rc = iscsi_check_assign_cmdsn(session,
(struct iscsi_nopin*)hdr);
if (rc)
goto done;
switch(opcode) {
case ISCSI_OP_LOGOUT_RSP:
if (datalen) {
rc = ISCSI_ERR_PROTO;
break;
}
conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
/* fall through */
case ISCSI_OP_LOGIN_RSP:
case ISCSI_OP_TEXT_RSP:
/*
* login related PDU's exp_statsn is handled in
* userspace
*/
if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
rc = ISCSI_ERR_CONN_FAILED;
list_del(&mtask->running);
if (conn->login_mtask != mtask)
__kfifo_put(session->mgmtpool.queue,
(void*)&mtask, sizeof(void*));
break;
case ISCSI_OP_SCSI_TMFUNC_RSP:
if (datalen) {
rc = ISCSI_ERR_PROTO;
break;
}
iscsi_tmf_rsp(conn, hdr);
break;
case ISCSI_OP_NOOP_IN:
if (hdr->ttt != ISCSI_RESERVED_TAG || datalen) {
rc = ISCSI_ERR_PROTO;
break;
}
conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
rc = ISCSI_ERR_CONN_FAILED;
list_del(&mtask->running);
if (conn->login_mtask != mtask)
__kfifo_put(session->mgmtpool.queue,
(void*)&mtask, sizeof(void*));
break;
default:
rc = ISCSI_ERR_BAD_OPCODE;
break;
}
} else if (itt == ISCSI_RESERVED_TAG) {
rc = iscsi_check_assign_cmdsn(session,
(struct iscsi_nopin*)hdr);
if (rc)
goto done;
switch(opcode) {
case ISCSI_OP_NOOP_IN:
if (datalen) {
rc = ISCSI_ERR_PROTO;
break;
}
if (hdr->ttt == ISCSI_RESERVED_TAG)
break;
if (iscsi_recv_pdu(conn->cls_conn, hdr, NULL, 0))
rc = ISCSI_ERR_CONN_FAILED;
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;
/* we need sth like iscsi_async_event_rsp() */
rc = ISCSI_ERR_BAD_OPCODE;
break;
default:
rc = ISCSI_ERR_BAD_OPCODE;
break;
}
} else
rc = ISCSI_ERR_BAD_ITT;
done:
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);
/* verify itt (itt encoding: age+cid+itt) */
int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
uint32_t *ret_itt)
{
struct iscsi_session *session = conn->session;
struct iscsi_cmd_task *ctask;
uint32_t itt;
if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
if ((hdr->itt & ISCSI_AGE_MASK) !=
(session->age << ISCSI_AGE_SHIFT)) {
printk(KERN_ERR "iscsi: received itt %x expected "
"session age (%x)\n", hdr->itt,
session->age & ISCSI_AGE_MASK);
return ISCSI_ERR_BAD_ITT;
}
if ((hdr->itt & ISCSI_CID_MASK) !=
(conn->id << ISCSI_CID_SHIFT)) {
printk(KERN_ERR "iscsi: received itt %x, expected "
"CID (%x)\n", hdr->itt, conn->id);
return ISCSI_ERR_BAD_ITT;
}
itt = hdr->itt & ISCSI_ITT_MASK;
} else
itt = hdr->itt;
if (itt < session->cmds_max) {
ctask = session->cmds[itt];
if (!ctask->sc) {
printk(KERN_INFO "iscsi: dropping ctask with "
"itt 0x%x\n", ctask->itt);
/* force drop */
return ISCSI_ERR_NO_SCSI_CMD;
}
if (ctask->sc->SCp.phase != session->age) {
printk(KERN_ERR "iscsi: ctask's session age %d, "
"expected %d\n", ctask->sc->SCp.phase,
session->age);
return ISCSI_ERR_SESSION_FAILED;
}
}
*ret_itt = itt;
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_verify_itt);
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(conn->cls_conn, err);
}
EXPORT_SYMBOL_GPL(iscsi_conn_failure);
/**
* 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_transport *tt;
int rc = 0;
if (unlikely(conn->suspend_tx)) {
debug_scsi("conn %d Tx suspended!\n", conn->id);
return -ENODATA;
}
tt = conn->session->tt;
/*
* Transmit in the following order:
*
* 1) un-finished xmit (ctask or mtask)
* 2) immediate control PDUs
* 3) write data
* 4) SCSI commands
* 5) non-immediate control PDUs
*
* No need to lock around __kfifo_get as long as
* there's one producer and one consumer.
*/
BUG_ON(conn->ctask && conn->mtask);
if (conn->ctask) {
iscsi_get_ctask(conn->ctask);
rc = tt->xmit_cmd_task(conn, conn->ctask);
iscsi_put_ctask(conn->ctask);
if (rc)
goto again;
/* done with this in-progress ctask */
conn->ctask = NULL;
}
if (conn->mtask) {
rc = tt->xmit_mgmt_task(conn, conn->mtask);
if (rc)
goto again;
/* done with this in-progress mtask */
conn->mtask = NULL;
}
/* process immediate first */
if (unlikely(__kfifo_len(conn->immqueue))) {
while (__kfifo_get(conn->immqueue, (void*)&conn->mtask,
sizeof(void*))) {
spin_lock_bh(&conn->session->lock);
list_add_tail(&conn->mtask->running,
&conn->mgmt_run_list);
spin_unlock_bh(&conn->session->lock);
rc = tt->xmit_mgmt_task(conn, conn->mtask);
if (rc)
goto again;
}
/* done with this mtask */
conn->mtask = NULL;
}
/* process command queue */
spin_lock_bh(&conn->session->lock);
while (!list_empty(&conn->xmitqueue)) {
/*
* iscsi tcp may readd the task to the xmitqueue to send
* write data
*/
conn->ctask = list_entry(conn->xmitqueue.next,
struct iscsi_cmd_task, running);
conn->ctask->state = ISCSI_TASK_RUNNING;
list_move_tail(conn->xmitqueue.next, &conn->run_list);
__iscsi_get_ctask(conn->ctask);
spin_unlock_bh(&conn->session->lock);
rc = tt->xmit_cmd_task(conn, conn->ctask);
if (rc)
goto again;
spin_lock_bh(&conn->session->lock);
__iscsi_put_ctask(conn->ctask);
if (rc) {
spin_unlock_bh(&conn->session->lock);
goto again;
}
}
spin_unlock_bh(&conn->session->lock);
/* done with this ctask */
conn->ctask = NULL;
/* process the rest control plane PDUs, if any */
if (unlikely(__kfifo_len(conn->mgmtqueue))) {
while (__kfifo_get(conn->mgmtqueue, (void*)&conn->mtask,
sizeof(void*))) {
spin_lock_bh(&conn->session->lock);
list_add_tail(&conn->mtask->running,
&conn->mgmt_run_list);
spin_unlock_bh(&conn->session->lock);
rc = tt->xmit_mgmt_task(conn, conn->mtask);
if (rc)
goto again;
}
/* done with this mtask */
conn->mtask = NULL;
}
return -ENODATA;
again:
if (unlikely(conn->suspend_tx))
return -ENODATA;
return rc;
}
static void iscsi_xmitworker(void *data)
{
struct iscsi_conn *conn = data;
int rc;
/*
* serialize Xmit worker on a per-connection basis.
*/
mutex_lock(&conn->xmitmutex);
do {
rc = iscsi_data_xmit(conn);
} while (rc >= 0 || rc == -EAGAIN);
mutex_unlock(&conn->xmitmutex);
}
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,
};
int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
{
struct Scsi_Host *host;
int reason = 0;
struct iscsi_session *session;
struct iscsi_conn *conn;
struct iscsi_cmd_task *ctask = NULL;
sc->scsi_done = done;
sc->result = 0;
sc->SCp.ptr = NULL;
host = sc->device->host;
session = iscsi_hostdata(host->hostdata);
spin_lock(&session->lock);
/*
* 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)
*/
if (session->state == ISCSI_STATE_IN_RECOVERY) {
reason = FAILURE_SESSION_IN_RECOVERY;
goto reject;
}
if (session->state == ISCSI_STATE_RECOVERY_FAILED)
reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
else if (session->state == ISCSI_STATE_TERMINATE)
reason = FAILURE_SESSION_TERMINATE;
else
reason = FAILURE_SESSION_FREED;
goto fault;
}
/*
* Check for iSCSI window and take care of CmdSN wrap-around
*/
if ((int)(session->max_cmdsn - session->cmdsn) < 0) {
reason = FAILURE_WINDOW_CLOSED;
goto reject;
}
conn = session->leadconn;
if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
sizeof(void*))) {
reason = FAILURE_OOM;
goto reject;
}
sc->SCp.phase = session->age;
sc->SCp.ptr = (char *)ctask;
atomic_set(&ctask->refcount, 1);
ctask->state = ISCSI_TASK_PENDING;
ctask->mtask = NULL;
ctask->conn = conn;
ctask->sc = sc;
INIT_LIST_HEAD(&ctask->running);
ctask->total_length = sc->request_bufflen;
iscsi_prep_scsi_cmd_pdu(ctask);
session->tt->init_cmd_task(ctask);
list_add_tail(&ctask->running, &conn->xmitqueue);
debug_scsi(
"ctask enq [%s cid %d sc %p cdb 0x%x itt 0x%x len %d cmdsn %d "
"win %d]\n",
sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
conn->id, sc, sc->cmnd[0], ctask->itt, sc->request_bufflen,
session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
spin_unlock(&session->lock);
scsi_queue_work(host, &conn->xmitwork);
return 0;
reject:
spin_unlock(&session->lock);
debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
return SCSI_MLQUEUE_HOST_BUSY;
fault:
spin_unlock(&session->lock);
printk(KERN_ERR "iscsi: cmd 0x%x is not queued (%d)\n",
sc->cmnd[0], reason);
sc->result = (DID_NO_CONNECT << 16);
sc->resid = sc->request_bufflen;
sc->scsi_done(sc);
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_queuecommand);
int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
{
if (depth > ISCSI_MAX_CMD_PER_LUN)
depth = ISCSI_MAX_CMD_PER_LUN;
scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
return sdev->queue_depth;
}
EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
static int
iscsi_conn_send_generic(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
char *data, uint32_t data_size)
{
struct iscsi_session *session = conn->session;
struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
struct iscsi_mgmt_task *mtask;
spin_lock_bh(&session->lock);
if (session->state == ISCSI_STATE_TERMINATE) {
spin_unlock_bh(&session->lock);
return -EPERM;
}
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 mtask can be used. Same ITT must be used.
* Note that login_mtask is preallocated at conn_create().
*/
mtask = conn->login_mtask;
else {
BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
if (!__kfifo_get(session->mgmtpool.queue,
(void*)&mtask, sizeof(void*))) {
spin_unlock_bh(&session->lock);
return -ENOSPC;
}
}
/*
* pre-format CmdSN for outgoing PDU.
*/
if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
hdr->itt = mtask->itt | (conn->id << ISCSI_CID_SHIFT) |
(session->age << ISCSI_AGE_SHIFT);
nop->cmdsn = cpu_to_be32(session->cmdsn);
if (conn->c_stage == ISCSI_CONN_STARTED &&
!(hdr->opcode & ISCSI_OP_IMMEDIATE))
session->cmdsn++;
} else
/* do not advance CmdSN */
nop->cmdsn = cpu_to_be32(session->cmdsn);
if (data_size) {
memcpy(mtask->data, data, data_size);
mtask->data_count = data_size;
} else
mtask->data_count = 0;
INIT_LIST_HEAD(&mtask->running);
memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
if (session->tt->init_mgmt_task)
session->tt->init_mgmt_task(conn, mtask, data, data_size);
spin_unlock_bh(&session->lock);
debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
hdr->opcode, hdr->itt, data_size);
/*
* since send_pdu() could be called at least from two contexts,
* we need to serialize __kfifo_put, so we don't have to take
* additional lock on fast data-path
*/
if (hdr->opcode & ISCSI_OP_IMMEDIATE)
__kfifo_put(conn->immqueue, (void*)&mtask, sizeof(void*));
else
__kfifo_put(conn->mgmtqueue, (void*)&mtask, sizeof(void*));
scsi_queue_work(session->host, &conn->xmitwork);
return 0;
}
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;
int rc;
mutex_lock(&conn->xmitmutex);
rc = iscsi_conn_send_generic(conn, hdr, data, data_size);
mutex_unlock(&conn->xmitmutex);
return rc;
}
EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
{
struct iscsi_session *session = class_to_transport_session(cls_session);
struct iscsi_conn *conn = session->leadconn;
spin_lock_bh(&session->lock);
if (session->state != ISCSI_STATE_LOGGED_IN) {
session->state = ISCSI_STATE_RECOVERY_FAILED;
if (conn)
wake_up(&conn->ehwait);
}
spin_unlock_bh(&session->lock);
}
EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
int iscsi_eh_host_reset(struct scsi_cmnd *sc)
{
struct Scsi_Host *host = sc->device->host;
struct iscsi_session *session = iscsi_hostdata(host->hostdata);
struct iscsi_conn *conn = session->leadconn;
int fail_session = 0;
spin_lock_bh(&session->lock);
if (session->state == ISCSI_STATE_TERMINATE) {
failed:
debug_scsi("failing host reset: session terminated "
"[CID %d age %d]", conn->id, session->age);
spin_unlock_bh(&session->lock);
return FAILED;
}
if (sc->SCp.phase == session->age) {
debug_scsi("failing connection CID %d due to SCSI host reset",
conn->id);
fail_session = 1;
}
spin_unlock_bh(&session->lock);
/*
* we drop the lock here but the leadconn cannot be destoyed while
* we are in the scsi eh
*/
if (fail_session)
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
debug_scsi("iscsi_eh_host_reset 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);
spin_lock_bh(&session->lock);
if (session->state == ISCSI_STATE_LOGGED_IN)
printk(KERN_INFO "iscsi: host reset succeeded\n");
else
goto failed;
spin_unlock_bh(&session->lock);
return SUCCESS;
}
EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
static void iscsi_tmabort_timedout(unsigned long data)
{
struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)data;
struct iscsi_conn *conn = ctask->conn;
struct iscsi_session *session = conn->session;
spin_lock(&session->lock);
if (conn->tmabort_state == TMABORT_INITIAL) {
conn->tmabort_state = TMABORT_TIMEDOUT;
debug_scsi("tmabort timedout [sc %p itt 0x%x]\n",
ctask->sc, ctask->itt);
/* unblock eh_abort() */
wake_up(&conn->ehwait);
}
spin_unlock(&session->lock);
}
/* must be called with the mutex lock */
static int iscsi_exec_abort_task(struct scsi_cmnd *sc,
struct iscsi_cmd_task *ctask)
{
struct iscsi_conn *conn = ctask->conn;
struct iscsi_session *session = conn->session;
struct iscsi_tm *hdr = &conn->tmhdr;
int rc;
/*
* ctask timed out but session is OK requests must be serialized.
*/
memset(hdr, 0, sizeof(struct iscsi_tm));
hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
hdr->flags = ISCSI_TM_FUNC_ABORT_TASK;
hdr->flags |= ISCSI_FLAG_CMD_FINAL;
memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
hdr->rtt = ctask->hdr->itt;
hdr->refcmdsn = ctask->hdr->cmdsn;
rc = iscsi_conn_send_generic(conn, (struct iscsi_hdr *)hdr,
NULL, 0);
if (rc) {
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
debug_scsi("abort sent failure [itt 0x%x] %d", ctask->itt, rc);
return rc;
}
debug_scsi("abort sent [itt 0x%x]\n", ctask->itt);
spin_lock_bh(&session->lock);
ctask->mtask = (struct iscsi_mgmt_task *)
session->mgmt_cmds[(hdr->itt & ISCSI_ITT_MASK) -
ISCSI_MGMT_ITT_OFFSET];
if (conn->tmabort_state == TMABORT_INITIAL) {
conn->tmfcmd_pdus_cnt++;
conn->tmabort_timer.expires = 10*HZ + jiffies;
conn->tmabort_timer.function = iscsi_tmabort_timedout;
conn->tmabort_timer.data = (unsigned long)ctask;
add_timer(&conn->tmabort_timer);
debug_scsi("abort set timeout [itt 0x%x]", ctask->itt);
}
spin_unlock_bh(&session->lock);
mutex_unlock(&conn->xmitmutex);
/*
* block eh thread until:
*
* 1) abort response
* 2) abort timeout
* 3) session is terminated or restarted or userspace has
* given up on recovery
*/
wait_event_interruptible(conn->ehwait,
sc->SCp.phase != session->age ||
session->state != ISCSI_STATE_LOGGED_IN ||
conn->tmabort_state != TMABORT_INITIAL);
if (signal_pending(current))
flush_signals(current);
del_timer_sync(&conn->tmabort_timer);
mutex_lock(&conn->xmitmutex);
return 0;
}
/*
* xmit mutex and session lock must be held
*/
static struct iscsi_mgmt_task *
iscsi_remove_mgmt_task(struct kfifo *fifo, uint32_t itt)
{
int i, nr_tasks = __kfifo_len(fifo) / sizeof(void*);
struct iscsi_mgmt_task *task;
debug_scsi("searching %d tasks\n", nr_tasks);
for (i = 0; i < nr_tasks; i++) {
__kfifo_get(fifo, (void*)&task, sizeof(void*));
debug_scsi("check task %u\n", task->itt);
if (task->itt == itt) {
debug_scsi("matched task\n");
return task;
}
__kfifo_put(fifo, (void*)&task, sizeof(void*));
}
return NULL;
}
static int iscsi_ctask_mtask_cleanup(struct iscsi_cmd_task *ctask)
{
struct iscsi_conn *conn = ctask->conn;
struct iscsi_session *session = conn->session;
if (!ctask->mtask)
return -EINVAL;
if (!iscsi_remove_mgmt_task(conn->immqueue, ctask->mtask->itt))
list_del(&ctask->mtask->running);
__kfifo_put(session->mgmtpool.queue, (void*)&ctask->mtask,
sizeof(void*));
ctask->mtask = NULL;
return 0;
}
/*
* session lock and xmitmutex must be held
*/
static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
int err)
{
struct scsi_cmnd *sc;
sc = ctask->sc;
if (!sc)
return;
conn->session->tt->cleanup_cmd_task(conn, ctask);
iscsi_ctask_mtask_cleanup(ctask);
sc->result = err;
sc->resid = sc->request_bufflen;
/* release ref from queuecommand */
__iscsi_put_ctask(ctask);
}
int iscsi_eh_abort(struct scsi_cmnd *sc)
{
struct iscsi_cmd_task *ctask;
struct iscsi_conn *conn;
struct iscsi_session *session;
int rc;
/*
* if session was ISCSI_STATE_IN_RECOVERY then we may not have
* got the command.
*/
if (!sc->SCp.ptr) {
debug_scsi("sc never reached iscsi layer or it completed.\n");
return SUCCESS;
}
ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
conn = ctask->conn;
session = conn->session;
conn->eh_abort_cnt++;
debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
mutex_lock(&conn->xmitmutex);
spin_lock_bh(&session->lock);
/*
* If we are not logged in or we have started a new session
* then let the host reset code handle this
*/
if (session->state != ISCSI_STATE_LOGGED_IN ||
sc->SCp.phase != session->age)
goto failed;
/* ctask completed before time out */
if (!ctask->sc) {
spin_unlock_bh(&session->lock);
debug_scsi("sc completed while abort in progress\n");
goto success_rel_mutex;
}
/* what should we do here ? */
if (conn->ctask == ctask) {
printk(KERN_INFO "iscsi: sc %p itt 0x%x partially sent. "
"Failing abort\n", sc, ctask->itt);
goto failed;
}
if (ctask->state == ISCSI_TASK_PENDING)
goto success_cleanup;
conn->tmabort_state = TMABORT_INITIAL;
spin_unlock_bh(&session->lock);
rc = iscsi_exec_abort_task(sc, ctask);
spin_lock_bh(&session->lock);
if (rc || sc->SCp.phase != session->age ||
session->state != ISCSI_STATE_LOGGED_IN)
goto failed;
iscsi_ctask_mtask_cleanup(ctask);
switch (conn->tmabort_state) {
case TMABORT_SUCCESS:
goto success_cleanup;
case TMABORT_NOT_FOUND:
if (!ctask->sc) {
/* ctask completed before tmf abort response */
spin_unlock_bh(&session->lock);
debug_scsi("sc completed while abort in progress\n");
goto success_rel_mutex;
}
/* fall through */
default:
/* timedout or failed */
spin_unlock_bh(&session->lock);
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
spin_lock_bh(&session->lock);
goto failed;
}
success_cleanup:
debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
spin_unlock_bh(&session->lock);
/*
* clean up task if aborted. we have the xmitmutex so grab
* the recv lock as a writer
*/
write_lock_bh(conn->recv_lock);
spin_lock(&session->lock);
fail_command(conn, ctask, DID_ABORT << 16);
spin_unlock(&session->lock);
write_unlock_bh(conn->recv_lock);
success_rel_mutex:
mutex_unlock(&conn->xmitmutex);
return SUCCESS;
failed:
spin_unlock_bh(&session->lock);
mutex_unlock(&conn->xmitmutex);
debug_scsi("abort failed [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
return FAILED;
}
EXPORT_SYMBOL_GPL(iscsi_eh_abort);
int
iscsi_pool_init(struct iscsi_queue *q, int max, void ***items, int item_size)
{
int i;
*items = kmalloc(max * sizeof(void*), GFP_KERNEL);
if (*items == NULL)
return -ENOMEM;
q->max = max;
q->pool = kmalloc(max * sizeof(void*), GFP_KERNEL);
if (q->pool == NULL) {
kfree(*items);
return -ENOMEM;
}
q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
GFP_KERNEL, NULL);
if (q->queue == ERR_PTR(-ENOMEM)) {
kfree(q->pool);
kfree(*items);
return -ENOMEM;
}
for (i = 0; i < max; i++) {
q->pool[i] = kmalloc(item_size, GFP_KERNEL);
if (q->pool[i] == NULL) {
int j;
for (j = 0; j < i; j++)
kfree(q->pool[j]);
kfifo_free(q->queue);
kfree(q->pool);
kfree(*items);
return -ENOMEM;
}
memset(q->pool[i], 0, item_size);
(*items)[i] = q->pool[i];
__kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
}
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_pool_init);
void iscsi_pool_free(struct iscsi_queue *q, void **items)
{
int i;
for (i = 0; i < q->max; i++)
kfree(items[i]);
kfree(q->pool);
kfree(items);
}
EXPORT_SYMBOL_GPL(iscsi_pool_free);
/*
* iSCSI Session's hostdata organization:
*
* *------------------* <== hostdata_session(host->hostdata)
* | ptr to class sess|
* |------------------| <== iscsi_hostdata(host->hostdata)
* | iscsi_session |
* *------------------*
*/
#define hostdata_privsize(_sz) (sizeof(unsigned long) + _sz + \
_sz % sizeof(unsigned long))
#define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
/**
* iscsi_session_setup - create iscsi cls session and host and session
* @scsit: scsi transport template
* @iscsit: iscsi transport template
* @initial_cmdsn: initial CmdSN
* @hostno: host no allocated
*
* This can be used by software iscsi_transports that allocate
* a session per scsi host.
**/
struct iscsi_cls_session *
iscsi_session_setup(struct iscsi_transport *iscsit,
struct scsi_transport_template *scsit,
int cmd_task_size, int mgmt_task_size,
uint32_t initial_cmdsn, uint32_t *hostno)
{
struct Scsi_Host *shost;
struct iscsi_session *session;
struct iscsi_cls_session *cls_session;
int cmd_i;
shost = scsi_host_alloc(iscsit->host_template,
hostdata_privsize(sizeof(*session)));
if (!shost)
return NULL;
shost->max_id = 1;
shost->max_channel = 0;
shost->max_lun = iscsit->max_lun;
shost->max_cmd_len = iscsit->max_cmd_len;
shost->transportt = scsit;
shost->transportt->create_work_queue = 1;
*hostno = shost->host_no;
session = iscsi_hostdata(shost->hostdata);
memset(session, 0, sizeof(struct iscsi_session));
session->host = shost;
session->state = ISCSI_STATE_FREE;
session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
session->cmds_max = ISCSI_XMIT_CMDS_MAX;
session->cmdsn = initial_cmdsn;
session->exp_cmdsn = initial_cmdsn + 1;
session->max_cmdsn = initial_cmdsn + 1;
session->max_r2t = 1;
session->tt = iscsit;
/* initialize SCSI PDU commands pool */
if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
(void***)&session->cmds,
cmd_task_size + sizeof(struct iscsi_cmd_task)))
goto cmdpool_alloc_fail;
/* pre-format cmds pool with ITT */
for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
if (cmd_task_size)
ctask->dd_data = &ctask[1];
ctask->itt = cmd_i;
INIT_LIST_HEAD(&ctask->running);
}
spin_lock_init(&session->lock);
INIT_LIST_HEAD(&session->connections);
/* initialize immediate command pool */
if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
(void***)&session->mgmt_cmds,
mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
goto mgmtpool_alloc_fail;
/* pre-format immediate cmds pool with ITT */
for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
if (mgmt_task_size)
mtask->dd_data = &mtask[1];
mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
INIT_LIST_HEAD(&mtask->running);
}
if (scsi_add_host(shost, NULL))
goto add_host_fail;
if (!try_module_get(iscsit->owner))
goto cls_session_fail;
cls_session = iscsi_create_session(shost, iscsit, 0);
if (!cls_session)
goto module_put;
*(unsigned long*)shost->hostdata = (unsigned long)cls_session;
return cls_session;
module_put:
module_put(iscsit->owner);
cls_session_fail:
scsi_remove_host(shost);
add_host_fail:
iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
mgmtpool_alloc_fail:
iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
cmdpool_alloc_fail:
scsi_host_put(shost);
return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_session_setup);
/**
* iscsi_session_teardown - destroy session, host, and cls_session
* shost: scsi host
*
* This can be used by software iscsi_transports that allocate
* a session per scsi host.
**/
void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
{
struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
struct module *owner = cls_session->transport->owner;
scsi_remove_host(shost);
iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
kfree(session->targetname);
iscsi_destroy_session(cls_session);
scsi_host_put(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
* @conn_idx: cid
**/
struct iscsi_cls_conn *
iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
{
struct iscsi_session *session = class_to_transport_session(cls_session);
struct iscsi_conn *conn;
struct iscsi_cls_conn *cls_conn;
char *data;
cls_conn = iscsi_create_conn(cls_session, conn_idx);
if (!cls_conn)
return NULL;
conn = cls_conn->dd_data;
memset(conn, 0, 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->tmabort_state = TMABORT_INITIAL;
INIT_LIST_HEAD(&conn->run_list);
INIT_LIST_HEAD(&conn->mgmt_run_list);
INIT_LIST_HEAD(&conn->xmitqueue);
/* initialize general immediate & non-immediate PDU commands queue */
conn->immqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
GFP_KERNEL, NULL);
if (conn->immqueue == ERR_PTR(-ENOMEM))
goto immqueue_alloc_fail;
conn->mgmtqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
GFP_KERNEL, NULL);
if (conn->mgmtqueue == ERR_PTR(-ENOMEM))
goto mgmtqueue_alloc_fail;
INIT_WORK(&conn->xmitwork, iscsi_xmitworker, conn);
/* allocate login_mtask used for the login/text sequences */
spin_lock_bh(&session->lock);
if (!__kfifo_get(session->mgmtpool.queue,
(void*)&conn->login_mtask,
sizeof(void*))) {
spin_unlock_bh(&session->lock);
goto login_mtask_alloc_fail;
}
spin_unlock_bh(&session->lock);
data = kmalloc(DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH, GFP_KERNEL);
if (!data)
goto login_mtask_data_alloc_fail;
conn->login_mtask->data = conn->data = data;
init_timer(&conn->tmabort_timer);
mutex_init(&conn->xmitmutex);
init_waitqueue_head(&conn->ehwait);
return cls_conn;
login_mtask_data_alloc_fail:
__kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
sizeof(void*));
login_mtask_alloc_fail:
kfifo_free(conn->mgmtqueue);
mgmtqueue_alloc_fail:
kfifo_free(conn->immqueue);
immqueue_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;
set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
mutex_lock(&conn->xmitmutex);
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);
mutex_unlock(&conn->xmitmutex);
/*
* 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);
printk(KERN_INFO "iscsi: scsi 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);
}
spin_lock_bh(&session->lock);
kfree(conn->data);
kfree(conn->persistent_address);
__kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
sizeof(void*));
list_del(&conn->item);
if (list_empty(&session->connections))
session->leadconn = NULL;
if (session->leadconn && session->leadconn == conn)
session->leadconn = container_of(session->connections.next,
struct iscsi_conn, item);
if (session->leadconn == NULL)
/* no connections exits.. reset sequencing */
session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1;
spin_unlock_bh(&session->lock);
kfifo_free(conn->immqueue);
kfifo_free(conn->mgmtqueue);
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) {
printk(KERN_ERR "iscsi: can't start unbound connection\n");
return -EPERM;
}
if ((session->imm_data_en || !session->initial_r2t_en) &&
session->first_burst > session->max_burst) {
printk("iscsi: invalid burst lengths: "
"first_burst %d max_burst %d\n",
session->first_burst, session->max_burst);
return -EINVAL;
}
spin_lock_bh(&session->lock);
conn->c_stage = ISCSI_CONN_STARTED;
session->state = ISCSI_STATE_LOGGED_IN;
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->tmabort_state = TMABORT_INITIAL;
session->age++;
spin_unlock_bh(&session->lock);
iscsi_unblock_session(session_to_cls(session));
wake_up(&conn->ehwait);
return 0;
case STOP_CONN_TERM:
conn->stop_stage = 0;
break;
default:
break;
}
spin_unlock_bh(&session->lock);
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_conn_start);
static void
flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
{
struct iscsi_mgmt_task *mtask, *tmp;
/* handle pending */
while (__kfifo_get(conn->immqueue, (void*)&mtask, sizeof(void*)) ||
__kfifo_get(conn->mgmtqueue, (void*)&mtask, sizeof(void*))) {
if (mtask == conn->login_mtask)
continue;
debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
__kfifo_put(session->mgmtpool.queue, (void*)&mtask,
sizeof(void*));
}
/* handle running */
list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
list_del(&mtask->running);
if (mtask == conn->login_mtask)
continue;
__kfifo_put(session->mgmtpool.queue, (void*)&mtask,
sizeof(void*));
}
conn->mtask = NULL;
}
/* Fail commands. Mutex and session lock held and recv side suspended */
static void fail_all_commands(struct iscsi_conn *conn)
{
struct iscsi_cmd_task *ctask, *tmp;
/* flush pending */
list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
debug_scsi("failing pending sc %p itt 0x%x\n", ctask->sc,
ctask->itt);
fail_command(conn, ctask, DID_BUS_BUSY << 16);
}
/* fail all other running */
list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
debug_scsi("failing in progress sc %p itt 0x%x\n",
ctask->sc, ctask->itt);
fail_command(conn, ctask, DID_BUS_BUSY << 16);
}
conn->ctask = NULL;
}
static void iscsi_start_session_recovery(struct iscsi_session *session,
struct iscsi_conn *conn, int flag)
{
int old_stop_stage;
spin_lock_bh(&session->lock);
if (conn->stop_stage == STOP_CONN_TERM) {
spin_unlock_bh(&session->lock);
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;
set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
spin_unlock_bh(&session->lock);
write_lock_bh(conn->recv_lock);
set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
write_unlock_bh(conn->recv_lock);
mutex_lock(&conn->xmitmutex);
/*
* 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) {
debug_scsi("blocking session\n");
iscsi_block_session(session_to_cls(session));
}
}
/*
* flush queues.
*/
spin_lock_bh(&session->lock);
fail_all_commands(conn);
flush_control_queues(session, conn);
spin_unlock_bh(&session->lock);
mutex_unlock(&conn->xmitmutex);
}
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:
printk(KERN_ERR "iscsi: 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 = class_to_transport_session(cls_session);
struct iscsi_conn *tmp = ERR_PTR(-EEXIST), *conn = cls_conn->dd_data;
/* lookup for existing connection */
spin_lock_bh(&session->lock);
list_for_each_entry(tmp, &session->connections, item) {
if (tmp == conn) {
if (conn->c_stage != ISCSI_CONN_STOPPED ||
conn->stop_stage == STOP_CONN_TERM) {
printk(KERN_ERR "iscsi: can't bind "
"non-stopped connection (%d:%d)\n",
conn->c_stage, conn->stop_stage);
spin_unlock_bh(&session->lock);
return -EIO;
}
break;
}
}
if (tmp != conn) {
/* bind new iSCSI connection to session */
conn->session = session;
list_add(&conn->item, &session->connections);
}
spin_unlock_bh(&session->lock);
if (is_leading)
session->leadconn = conn;
/*
* 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);
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_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_TARGET_NAME:
/* this should not change between logins */
if (session->targetname)
break;
session->targetname = kstrdup(buf, GFP_KERNEL);
if (!session->targetname)
return -ENOMEM;
break;
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:
/*
* this is the address returned in discovery so it should
* not change between logins.
*/
if (conn->persistent_address)
break;
conn->persistent_address = kstrdup(buf, GFP_KERNEL);
if (!conn->persistent_address)
return -ENOMEM;
break;
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 Scsi_Host *shost = iscsi_session_to_shost(cls_session);
struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
int len;
switch(param) {
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;
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_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);
MODULE_AUTHOR("Mike Christie");
MODULE_DESCRIPTION("iSCSI library functions");
MODULE_LICENSE("GPL");
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