From 6eabafbe6616266e8de61980a7dac5ecc1ba1113 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Thu, 31 Jan 2008 13:36:43 -0600 Subject: [SCSI] iscsi class, libiscsi: add iscsi sysfs session state file This adds a iscsi session state file which exports the session state for both software and hardware iscsi. It also hooks libiscsi in. Signed-off-by: Mike Christie Signed-off-by: James Bottomley --- drivers/scsi/libiscsi.c | 41 +++++++++----- drivers/scsi/scsi_transport_iscsi.c | 107 +++++++++++++++++++++++++++++++++++- 2 files changed, 130 insertions(+), 18 deletions(-) (limited to 'drivers/scsi') diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c index e7942628ac4..c8c00e17341 100644 --- a/drivers/scsi/libiscsi.c +++ b/drivers/scsi/libiscsi.c @@ -996,6 +996,7 @@ enum { FAILURE_SESSION_IN_RECOVERY, FAILURE_SESSION_RECOVERY_TIMEOUT, FAILURE_SESSION_LOGGING_OUT, + FAILURE_SESSION_NOT_READY, }; int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *)) @@ -1016,6 +1017,12 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *)) session = iscsi_hostdata(host->hostdata); spin_lock(&session->lock); + reason = iscsi_session_chkready(session_to_cls(session)); + if (reason) { + sc->result = reason; + goto fault; + } + /* * ISCSI_STATE_FAILED is a temp. state. The recovery * code will decide what is best to do with command queued @@ -1032,18 +1039,23 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *)) switch (session->state) { case ISCSI_STATE_IN_RECOVERY: reason = FAILURE_SESSION_IN_RECOVERY; - goto reject; + sc->result = DID_IMM_RETRY << 16; + break; case ISCSI_STATE_LOGGING_OUT: reason = FAILURE_SESSION_LOGGING_OUT; - goto reject; + sc->result = DID_IMM_RETRY << 16; + break; case ISCSI_STATE_RECOVERY_FAILED: reason = FAILURE_SESSION_RECOVERY_TIMEOUT; + sc->result = DID_NO_CONNECT << 16; break; case ISCSI_STATE_TERMINATE: reason = FAILURE_SESSION_TERMINATE; + sc->result = DID_NO_CONNECT << 16; break; default: reason = FAILURE_SESSION_FREED; + sc->result = DID_NO_CONNECT << 16; } goto fault; } @@ -1051,6 +1063,7 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *)) conn = session->leadconn; if (!conn) { reason = FAILURE_SESSION_FREED; + sc->result = DID_NO_CONNECT << 16; goto fault; } @@ -1090,9 +1103,7 @@ reject: 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); + debug_scsi("iscsi: cmd 0x%x is not queued (%d)\n", sc->cmnd[0], reason); scsi_set_resid(sc, scsi_bufflen(sc)); sc->scsi_done(sc); spin_lock(host->host_lock); @@ -1238,7 +1249,8 @@ static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn, * Fail commands. session lock held and recv side suspended and xmit * thread flushed */ -static void fail_all_commands(struct iscsi_conn *conn, unsigned lun) +static void fail_all_commands(struct iscsi_conn *conn, unsigned lun, + int error) { struct iscsi_cmd_task *ctask, *tmp; @@ -1250,7 +1262,7 @@ static void fail_all_commands(struct iscsi_conn *conn, unsigned lun) if (lun == ctask->sc->device->lun || lun == -1) { debug_scsi("failing pending sc %p itt 0x%x\n", ctask->sc, ctask->itt); - fail_command(conn, ctask, DID_BUS_BUSY << 16); + fail_command(conn, ctask, error << 16); } } @@ -1258,7 +1270,7 @@ static void fail_all_commands(struct iscsi_conn *conn, unsigned lun) if (lun == ctask->sc->device->lun || lun == -1) { debug_scsi("failing requeued sc %p itt 0x%x\n", ctask->sc, ctask->itt); - fail_command(conn, ctask, DID_BUS_BUSY << 16); + fail_command(conn, ctask, error << 16); } } @@ -1572,7 +1584,7 @@ int iscsi_eh_device_reset(struct scsi_cmnd *sc) /* need to grab the recv lock then session lock */ write_lock_bh(conn->recv_lock); spin_lock(&session->lock); - fail_all_commands(conn, sc->device->lun); + fail_all_commands(conn, sc->device->lun, DID_ERROR); conn->tmf_state = TMF_INITIAL; spin_unlock(&session->lock); write_unlock_bh(conn->recv_lock); @@ -2018,11 +2030,7 @@ int iscsi_conn_start(struct iscsi_cls_conn *cls_conn) conn->stop_stage = 0; conn->tmf_state = TMF_INITIAL; session->age++; - spin_unlock_bh(&session->lock); - - iscsi_unblock_session(session_to_cls(session)); - wake_up(&conn->ehwait); - return 0; + break; case STOP_CONN_TERM: conn->stop_stage = 0; break; @@ -2031,6 +2039,8 @@ int iscsi_conn_start(struct iscsi_cls_conn *cls_conn) } spin_unlock_bh(&session->lock); + iscsi_unblock_session(session_to_cls(session)); + wake_up(&conn->ehwait); return 0; } EXPORT_SYMBOL_GPL(iscsi_conn_start); @@ -2122,7 +2132,8 @@ static void iscsi_start_session_recovery(struct iscsi_session *session, * flush queues. */ spin_lock_bh(&session->lock); - fail_all_commands(conn, -1); + fail_all_commands(conn, -1, + STOP_CONN_RECOVER ? DID_BUS_BUSY : DID_ERROR); flush_control_queues(session, conn); spin_unlock_bh(&session->lock); mutex_unlock(&session->eh_mutex); diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c index 0d7b4e79415..f876b0ae521 100644 --- a/drivers/scsi/scsi_transport_iscsi.c +++ b/drivers/scsi/scsi_transport_iscsi.c @@ -30,7 +30,7 @@ #include #include -#define ISCSI_SESSION_ATTRS 18 +#define ISCSI_SESSION_ATTRS 19 #define ISCSI_CONN_ATTRS 11 #define ISCSI_HOST_ATTRS 4 #define ISCSI_TRANSPORT_VERSION "2.0-867" @@ -221,6 +221,54 @@ static struct iscsi_cls_conn *iscsi_conn_lookup(uint32_t sid, uint32_t cid) * The following functions can be used by LLDs that allocate * their own scsi_hosts or by software iscsi LLDs */ +static struct { + int value; + char *name; +} iscsi_session_state_names[] = { + { ISCSI_SESSION_LOGGED_IN, "LOGGED_IN" }, + { ISCSI_SESSION_FAILED, "FAILED" }, + { ISCSI_SESSION_FREE, "FREE" }, +}; + +const char *iscsi_session_state_name(int state) +{ + int i; + char *name = NULL; + + for (i = 0; i < ARRAY_SIZE(iscsi_session_state_names); i++) { + if (iscsi_session_state_names[i].value == state) { + name = iscsi_session_state_names[i].name; + break; + } + } + return name; +} + +int iscsi_session_chkready(struct iscsi_cls_session *session) +{ + unsigned long flags; + int err; + + spin_lock_irqsave(&session->lock, flags); + switch (session->state) { + case ISCSI_SESSION_LOGGED_IN: + err = 0; + break; + case ISCSI_SESSION_FAILED: + err = DID_IMM_RETRY << 16; + break; + case ISCSI_SESSION_FREE: + err = DID_NO_CONNECT << 16; + break; + default: + err = DID_NO_CONNECT << 16; + break; + } + spin_unlock_irqrestore(&session->lock, flags); + return err; +} +EXPORT_SYMBOL_GPL(iscsi_session_chkready); + static void iscsi_session_release(struct device *dev) { struct iscsi_cls_session *session = iscsi_dev_to_session(dev); @@ -259,26 +307,57 @@ static void session_recovery_timedout(struct work_struct *work) struct iscsi_cls_session *session = container_of(work, struct iscsi_cls_session, recovery_work.work); + unsigned long flags; dev_printk(KERN_INFO, &session->dev, "iscsi: session recovery timed " "out after %d secs\n", session->recovery_tmo); + spin_lock_irqsave(&session->lock, flags); + switch (session->state) { + case ISCSI_SESSION_FAILED: + session->state = ISCSI_SESSION_FREE; + break; + case ISCSI_SESSION_LOGGED_IN: + case ISCSI_SESSION_FREE: + /* we raced with the unblock's flush */ + spin_unlock_irqrestore(&session->lock, flags); + return; + } + spin_unlock_irqrestore(&session->lock, flags); + if (session->transport->session_recovery_timedout) session->transport->session_recovery_timedout(session); scsi_target_unblock(&session->dev); } -void iscsi_unblock_session(struct iscsi_cls_session *session) +void __iscsi_unblock_session(struct iscsi_cls_session *session) { if (!cancel_delayed_work(&session->recovery_work)) flush_workqueue(iscsi_eh_timer_workq); scsi_target_unblock(&session->dev); } + +void iscsi_unblock_session(struct iscsi_cls_session *session) +{ + unsigned long flags; + + spin_lock_irqsave(&session->lock, flags); + session->state = ISCSI_SESSION_LOGGED_IN; + spin_unlock_irqrestore(&session->lock, flags); + + __iscsi_unblock_session(session); +} EXPORT_SYMBOL_GPL(iscsi_unblock_session); void iscsi_block_session(struct iscsi_cls_session *session) { + unsigned long flags; + + spin_lock_irqsave(&session->lock, flags); + session->state = ISCSI_SESSION_FAILED; + spin_unlock_irqrestore(&session->lock, flags); + scsi_target_block(&session->dev); queue_delayed_work(iscsi_eh_timer_workq, &session->recovery_work, session->recovery_tmo * HZ); @@ -327,10 +406,12 @@ iscsi_alloc_session(struct Scsi_Host *shost, session->transport = transport; session->recovery_tmo = 120; + session->state = ISCSI_SESSION_FREE; INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout); INIT_LIST_HEAD(&session->host_list); INIT_LIST_HEAD(&session->sess_list); INIT_WORK(&session->unbind_work, __iscsi_unbind_session); + spin_lock_init(&session->lock); /* this is released in the dev's release function */ scsi_host_get(shost); @@ -444,7 +525,10 @@ void iscsi_remove_session(struct iscsi_cls_session *session) * If we are blocked let commands flow again. The lld or iscsi * layer should set up the queuecommand to fail commands. */ - iscsi_unblock_session(session); + spin_lock_irqsave(&session->lock, flags); + session->state = ISCSI_SESSION_FREE; + spin_unlock_irqrestore(&session->lock, flags); + __iscsi_unblock_session(session); iscsi_unbind_session(session); /* * If the session dropped while removing devices then we need to make @@ -661,16 +745,23 @@ EXPORT_SYMBOL_GPL(iscsi_recv_pdu); void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error) { + struct iscsi_cls_session *session = iscsi_conn_to_session(conn); struct nlmsghdr *nlh; struct sk_buff *skb; struct iscsi_uevent *ev; struct iscsi_internal *priv; int len = NLMSG_SPACE(sizeof(*ev)); + unsigned long flags; priv = iscsi_if_transport_lookup(conn->transport); if (!priv) return; + spin_lock_irqsave(&session->lock, flags); + if (session->state == ISCSI_SESSION_LOGGED_IN) + session->state = ISCSI_SESSION_FAILED; + spin_unlock_irqrestore(&session->lock, flags); + skb = alloc_skb(len, GFP_ATOMIC); if (!skb) { dev_printk(KERN_ERR, &conn->dev, "iscsi: gracefully ignored " @@ -1246,6 +1337,15 @@ iscsi_session_attr(fast_abort, ISCSI_PARAM_FAST_ABORT, 0); iscsi_session_attr(abort_tmo, ISCSI_PARAM_ABORT_TMO, 0); iscsi_session_attr(lu_reset_tmo, ISCSI_PARAM_LU_RESET_TMO, 0); +static ssize_t +show_priv_session_state(struct class_device *cdev, char *buf) +{ + struct iscsi_cls_session *session = iscsi_cdev_to_session(cdev); + return sprintf(buf, "%s\n", iscsi_session_state_name(session->state)); +} +static ISCSI_CLASS_ATTR(priv_sess, state, S_IRUGO, show_priv_session_state, + NULL); + #define iscsi_priv_session_attr_show(field, format) \ static ssize_t \ show_priv_session_##field(struct class_device *cdev, char *buf) \ @@ -1472,6 +1572,7 @@ iscsi_register_transport(struct iscsi_transport *tt) SETUP_SESSION_RD_ATTR(abort_tmo, ISCSI_ABORT_TMO); SETUP_SESSION_RD_ATTR(lu_reset_tmo,ISCSI_LU_RESET_TMO); SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo); + SETUP_PRIV_SESSION_RD_ATTR(state); BUG_ON(count > ISCSI_SESSION_ATTRS); priv->session_attrs[count] = NULL; -- cgit v1.2.3