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-rw-r--r--drivers/scsi/libiscsi.c59
1 files changed, 50 insertions, 9 deletions
diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index a7c6e70f4ef..9584cbc082f 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -179,16 +179,15 @@ EXPORT_SYMBOL_GPL(iscsi_prep_scsi_cmd_pdu);
/**
* iscsi_complete_command - return command back to scsi-ml
- * @session: iscsi session
* @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_session *session,
- struct iscsi_cmd_task *ctask)
+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;
@@ -198,6 +197,35 @@ static void iscsi_complete_command(struct iscsi_session *session,
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)
+{
+ struct iscsi_conn *conn = ctask->conn;
+
+ if (atomic_dec_and_test(&ctask->refcount)) {
+ conn->session->tt->cleanup_cmd_task(conn, ctask);
+ 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
@@ -274,7 +302,7 @@ out:
(long)sc, sc->result, ctask->itt);
conn->scsirsp_pdus_cnt++;
- iscsi_complete_command(conn->session, ctask);
+ __iscsi_put_ctask(ctask);
return rc;
}
@@ -338,7 +366,7 @@ int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
conn->scsirsp_pdus_cnt++;
- iscsi_complete_command(session, ctask);
+ __iscsi_put_ctask(ctask);
}
break;
case ISCSI_OP_R2T:
@@ -563,7 +591,9 @@ static int iscsi_data_xmit(struct iscsi_conn *conn)
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 */
@@ -604,12 +634,19 @@ static int iscsi_data_xmit(struct iscsi_conn *conn)
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 */
@@ -659,6 +696,7 @@ enum {
FAILURE_SESSION_FAILED,
FAILURE_SESSION_FREED,
FAILURE_WINDOW_CLOSED,
+ FAILURE_OOM,
FAILURE_SESSION_TERMINATE,
FAILURE_SESSION_IN_RECOVERY,
FAILURE_SESSION_RECOVERY_TIMEOUT,
@@ -717,10 +755,15 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
conn = session->leadconn;
- __kfifo_get(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
+ 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;
@@ -1057,13 +1100,11 @@ static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
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;
- iscsi_complete_command(conn->session, ctask);
+ __iscsi_put_ctask(ctask);
}
int iscsi_eh_abort(struct scsi_cmnd *sc)