diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c index a7c6e70f4ef85c0aecf9421c013601d0cce2b7b9..9584cbc082fee79e4c65353ba1bd431e0332041f 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 @@ static int iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr, (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) diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h index 4900650bd08124642ff2539a61ceda6f10cc5a33..401192e56e502a6a69e2e1c14c4630678acbfed3 100644 --- a/include/scsi/libiscsi.h +++ b/include/scsi/libiscsi.h @@ -112,6 +112,7 @@ struct iscsi_cmd_task { /* state set/tested under session->lock */ int state; + atomic_t refcount; struct list_head running; /* running cmd list */ void *dd_data; /* driver/transport data */ };