From: Mike Christie Date: Fri, 19 May 2006 01:31:42 +0000 (-0500) Subject: [SCSI] iscsi: fix command requeues during iscsi recovery X-Git-Tag: v2.6.18-rc1~1092^2~57 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=656cffc95f0cb8211aa75eaca249e6ff4f59ec83;p=linux-2.6 [SCSI] iscsi: fix command requeues during iscsi recovery Do not flush queues then block session. This will cause commands to needlessly swing around on us and remove goofy recovery_failed field and replace with state value. And do not start recovery from within the host reset function. This causeis too many problems becuase open-iscsi was desinged to call out to userspace then have userpscae decide if we should go into recovery or kill the session. Signed-off-by: Mike Christie Signed-off-by: James Bottomley --- diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c index 580c050560..d810acae45 100644 --- a/drivers/scsi/libiscsi.c +++ b/drivers/scsi/libiscsi.c @@ -487,6 +487,11 @@ void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err) unsigned long flags; spin_lock_irqsave(&session->lock, flags); + if (session->state == ISCSI_STATE_FAILED) { + spin_unlock_irqrestore(&session->lock, flags); + return; + } + if (session->conn_cnt == 1 || session->leadconn == conn) session->state = ISCSI_STATE_FAILED; spin_unlock_irqrestore(&session->lock, flags); @@ -612,6 +617,7 @@ enum { FAILURE_SESSION_FREED, FAILURE_WINDOW_CLOSED, FAILURE_SESSION_TERMINATE, + FAILURE_SESSION_IN_RECOVERY, FAILURE_SESSION_RECOVERY_TIMEOUT, }; @@ -631,18 +637,30 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *)) spin_lock(&session->lock); - if (session->state != ISCSI_STATE_LOGGED_IN) { - if (session->recovery_failed) { - reason = FAILURE_SESSION_RECOVERY_TIMEOUT; - goto fault; - } else if (session->state == ISCSI_STATE_FAILED) { - reason = FAILURE_SESSION_FAILED; - goto reject; - } else if (session->state == ISCSI_STATE_TERMINATE) { - reason = FAILURE_SESSION_TERMINATE; + /* + * 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 fault; } - reason = FAILURE_SESSION_FREED; + + 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; } @@ -728,8 +746,8 @@ iscsi_conn_send_generic(struct iscsi_conn *conn, struct iscsi_hdr *hdr, */ mtask = conn->login_mtask; else { - BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE); - BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED); + 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, @@ -803,7 +821,7 @@ void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session) spin_lock_bh(&session->lock); if (session->state != ISCSI_STATE_LOGGED_IN) { - session->recovery_failed = 1; + session->state = ISCSI_STATE_RECOVERY_FAILED; if (conn) wake_up(&conn->ehwait); } @@ -838,20 +856,14 @@ failed: * we drop the lock here but the leadconn cannot be destoyed while * we are in the scsi eh */ - if (fail_session) { + if (fail_session) iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED); - /* - * if userspace cannot respond then we must kick this off - * here for it - */ - iscsi_start_session_recovery(session, conn, STOP_CONN_RECOVER); - } 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->recovery_failed); + session->state == ISCSI_STATE_RECOVERY_FAILED); if (signal_pending(current)) flush_signals(current); @@ -940,8 +952,7 @@ static int iscsi_exec_abort_task(struct scsi_cmnd *sc, wait_event_interruptible(conn->ehwait, sc->SCp.phase != session->age || session->state != ISCSI_STATE_LOGGED_IN || - conn->tmabort_state != TMABORT_INITIAL || - session->recovery_failed); + conn->tmabort_state != TMABORT_INITIAL); if (signal_pending(current)) flush_signals(current); del_timer_sync(&conn->tmabort_timer); @@ -1491,7 +1502,6 @@ int iscsi_conn_start(struct iscsi_cls_conn *cls_conn) conn->stop_stage = 0; conn->tmabort_state = TMABORT_INITIAL; session->age++; - session->recovery_failed = 0; spin_unlock_bh(&session->lock); iscsi_unblock_session(session_to_cls(session)); @@ -1566,8 +1576,8 @@ static void fail_all_commands(struct iscsi_conn *conn) conn->ctask = NULL; } -void iscsi_start_session_recovery(struct iscsi_session *session, - struct iscsi_conn *conn, int flag) +static void iscsi_start_session_recovery(struct iscsi_session *session, + struct iscsi_conn *conn, int flag) { int old_stop_stage; @@ -1597,19 +1607,10 @@ void iscsi_start_session_recovery(struct iscsi_session *session, set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx); if (session->conn_cnt == 0 || session->leadconn == conn) - session->state = ISCSI_STATE_FAILED; + session->state = ISCSI_STATE_IN_RECOVERY; spin_unlock_bh(&session->lock); - session->tt->terminate_conn(conn); - /* - * flush queues. - */ - spin_lock_bh(&session->lock); - fail_all_commands(conn); - flush_control_queues(session, conn); - spin_unlock_bh(&session->lock); - /* * for connection level recovery we should not calculate * header digest. conn->hdr_size used for optimization @@ -1619,18 +1620,26 @@ void iscsi_start_session_recovery(struct iscsi_session *session, if (flag == STOP_CONN_RECOVER) { conn->hdrdgst_en = 0; conn->datadgst_en = 0; - /* * if this is called from the eh and and from userspace * then we only need to block once. */ - if (session->state == ISCSI_STATE_FAILED && + if (session->state == ISCSI_STATE_IN_RECOVERY && old_stop_stage != STOP_CONN_RECOVER) iscsi_block_session(session_to_cls(session)); } + + session->tt->terminate_conn(conn); + /* + * 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); } -EXPORT_SYMBOL_GPL(iscsi_start_session_recovery); void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag) { diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h index 2dba929a2a..17b28f08b6 100644 --- a/include/scsi/libiscsi.h +++ b/include/scsi/libiscsi.h @@ -210,7 +210,6 @@ struct iscsi_session { * - mgmtpool, * * - r2tpool */ int state; /* session state */ - int recovery_failed; struct list_head item; int conn_cnt; int age; /* counts session re-opens */ @@ -241,8 +240,6 @@ iscsi_session_setup(struct iscsi_transport *, struct scsi_transport_template *, int, int, uint32_t, uint32_t *); extern void iscsi_session_teardown(struct iscsi_cls_session *); extern struct iscsi_session *class_to_transport_session(struct iscsi_cls_session *); -extern void iscsi_start_session_recovery(struct iscsi_session *, - struct iscsi_conn *, int); extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *); #define session_to_cls(_sess) \ diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h index c9e9475c6d..92129b97d3 100644 --- a/include/scsi/scsi_transport_iscsi.h +++ b/include/scsi/scsi_transport_iscsi.h @@ -173,6 +173,8 @@ struct iscsi_cls_conn { #define ISCSI_STATE_LOGGED_IN 2 #define ISCSI_STATE_FAILED 3 #define ISCSI_STATE_TERMINATE 4 +#define ISCSI_STATE_IN_RECOVERY 5 +#define ISCSI_STATE_RECOVERY_FAILED 6 struct iscsi_cls_session { struct list_head sess_list; /* item in session_list */