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[SCSI] libiscsi: do not take host lock in queuecommand 

iscsi_tcp, ib_iser, cxgb*, be2iscsi and bnx2i do not use
the host lock and do not take the session lock against
a irq, so this patch drops the DEF_SCSI_QCMD use. Instead
we just take the session lock and disable bhs.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
hifive-unleashed-5.1
Mike Christie 2010-12-31 02:22:21 -06:00 committed by James Bottomley
parent 1227633a44
commit f41d472179
2 changed files with 16 additions and 24 deletions
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37
drivers/scsi/libiscsi.c
View File

@ -505,6 +505,7 @@ static void iscsi_free_task(struct iscsi_task *task)
struct iscsi_conn *conn = task->conn;
struct iscsi_session *session = conn->session;
struct scsi_cmnd *sc = task->sc;
int oldstate = task->state;
ISCSI_DBG_SESSION(session, "freeing task itt 0x%x state %d sc %p\n",
task->itt, task->state, task->sc);
@ -525,10 +526,10 @@ static void iscsi_free_task(struct iscsi_task *task)
/* 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
* queue command may call this to free the task, so
* it will decide how to return sc to scsi-ml.
*/
if (sc->scsi_done)
if (oldstate != ISCSI_TASK_REQUEUE_SCSIQ)
sc->scsi_done(sc);
}
}
@ -572,7 +573,8 @@ static void iscsi_complete_task(struct iscsi_task *task, int state)
task->itt, task->state, task->sc);
if (task->state == ISCSI_TASK_COMPLETED ||
task->state == ISCSI_TASK_ABRT_TMF ||
task->state == ISCSI_TASK_ABRT_SESS_RECOV)
task->state == ISCSI_TASK_ABRT_SESS_RECOV ||
task->state == ISCSI_TASK_REQUEUE_SCSIQ)
return;
WARN_ON_ONCE(task->state == ISCSI_TASK_FREE);
task->state = state;
@ -1600,27 +1602,23 @@ enum {
FAILURE_SESSION_NOT_READY,
};
static int iscsi_queuecommand_lck(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc)
{
struct iscsi_cls_session *cls_session;
struct Scsi_Host *host;
struct iscsi_host *ihost;
int reason = 0;
struct iscsi_session *session;
struct iscsi_conn *conn;
struct iscsi_task *task = NULL;
sc->scsi_done = done;
sc->result = 0;
sc->SCp.ptr = NULL;
host = sc->device->host;
ihost = shost_priv(host);
spin_unlock(host->host_lock);
cls_session = starget_to_session(scsi_target(sc->device));
session = cls_session->dd_data;
spin_lock(&session->lock);
spin_lock_bh(&session->lock);
reason = iscsi_session_chkready(cls_session);
if (reason) {
@ -1706,25 +1704,21 @@ static int iscsi_queuecommand_lck(struct scsi_cmnd *sc, void (*done)(struct scsi
}
session->queued_cmdsn++;
spin_unlock(&session->lock);
spin_lock(host->host_lock);
spin_unlock_bh(&session->lock);
return 0;
prepd_reject:
sc->scsi_done = NULL;
iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
reject:
spin_unlock(&session->lock);
spin_unlock_bh(&session->lock);
ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
sc->cmnd[0], reason);
spin_lock(host->host_lock);
return SCSI_MLQUEUE_TARGET_BUSY;
prepd_fault:
sc->scsi_done = NULL;
iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
fault:
spin_unlock(&session->lock);
spin_unlock_bh(&session->lock);
ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n",
sc->cmnd[0], reason);
if (!scsi_bidi_cmnd(sc))
@ -1733,12 +1727,9 @@ fault:
scsi_out(sc)->resid = scsi_out(sc)->length;
scsi_in(sc)->resid = scsi_in(sc)->length;
}
done(sc);
spin_lock(host->host_lock);
sc->scsi_done(sc);
return 0;
}
DEF_SCSI_QCMD(iscsi_queuecommand)
EXPORT_SYMBOL_GPL(iscsi_queuecommand);
int iscsi_change_queue_depth(struct scsi_device *sdev, int depth, int reason)

3
include/scsi/libiscsi.h
View File

@ -89,6 +89,7 @@ enum {
ISCSI_TASK_RUNNING,
ISCSI_TASK_ABRT_TMF, /* aborted due to TMF */
ISCSI_TASK_ABRT_SESS_RECOV, /* aborted due to session recovery */
ISCSI_TASK_REQUEUE_SCSIQ, /* qcmd requeueing to scsi-ml */
};
struct iscsi_r2t_info {
@ -341,7 +342,7 @@ extern int iscsi_eh_abort(struct scsi_cmnd *sc);
extern int iscsi_eh_recover_target(struct scsi_cmnd *sc);
extern int iscsi_eh_session_reset(struct scsi_cmnd *sc);
extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
extern int iscsi_queuecommand(struct Scsi_Host *h, struct scsi_cmnd *sc);
extern int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc);
/*
* iSCSI host helpers.