diff options
Diffstat (limited to 'kernel/scsi_transport_iscsi.c')
| -rw-r--r-- | kernel/scsi_transport_iscsi.c | 178 |
1 files changed, 167 insertions, 11 deletions
diff --git a/kernel/scsi_transport_iscsi.c b/kernel/scsi_transport_iscsi.c index 7e5e168..4686f3a 100644 --- a/kernel/scsi_transport_iscsi.c +++ b/kernel/scsi_transport_iscsi.c @@ -30,7 +30,7 @@ #include "scsi_transport_iscsi.h" #include "iscsi_if.h" -#define ISCSI_SESSION_ATTRS 18 +#define ISCSI_SESSION_ATTRS 19 #define ISCSI_CONN_ATTRS 11 #define ISCSI_HOST_ATTRS 4 #define ISCSI_TRANSPORT_VERSION "2.0-724" @@ -127,12 +127,13 @@ static int iscsi_setup_host(struct transport_container *tc, struct device *dev, memset(ihost, 0, sizeof(*ihost)); INIT_LIST_HEAD(&ihost->sessions); mutex_init(&ihost->mutex); + atomic_set(&ihost->nr_scans, 0); - snprintf(ihost->unbind_workq_name, KOBJ_NAME_LEN, "iscsi_unbind_%d", + snprintf(ihost->scan_workq_name, KOBJ_NAME_LEN, "iscsi_scan_%d", shost->host_no); - ihost->unbind_workq = create_singlethread_workqueue( - ihost->unbind_workq_name); - if (!ihost->unbind_workq) + ihost->scan_workq = create_singlethread_workqueue( + ihost->scan_workq_name); + if (!ihost->scan_workq) return -ENOMEM; return 0; } @@ -143,7 +144,7 @@ static int iscsi_remove_host(struct transport_container *tc, struct device *dev, struct Scsi_Host *shost = dev_to_shost(dev); struct iscsi_host *ihost = shost->shost_data; - destroy_workqueue(ihost->unbind_workq); + destroy_workqueue(ihost->scan_workq); return 0; } @@ -221,6 +222,54 @@ 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); @@ -236,6 +285,25 @@ static int iscsi_is_session_dev(const struct device *dev) return dev->release == iscsi_session_release; } +/** + * iscsi_scan_finished - helper to report when running scans are done + * @shost: scsi host + * @time: scan run time + * + * This function can be used by drives like qla4xxx to report to the scsi + * layer when the scans it kicked off at module load time are done. + */ +int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time) +{ + struct iscsi_host *ihost = shost->shost_data; + /* + * qla4xxx will have kicked off some session unblocks before calling + * scsi_scan_host, so just wait for them to complete. + */ + return !atomic_read(&ihost->nr_scans); +} +EXPORT_SYMBOL_GPL(iscsi_scan_finished); + static int iscsi_user_scan(struct Scsi_Host *shost, uint channel, uint id, uint lun) { @@ -254,31 +322,94 @@ static int iscsi_user_scan(struct Scsi_Host *shost, uint channel, return 0; } +static void iscsi_scan_session(struct work_struct *work) +{ + struct iscsi_cls_session *session = + container_of(work, struct iscsi_cls_session, scan_work); + struct Scsi_Host *shost = iscsi_session_to_shost(session); + struct iscsi_host *ihost = shost->shost_data; + unsigned long flags; + + spin_lock_irqsave(&session->lock, flags); + if (session->state != ISCSI_SESSION_LOGGED_IN) { + spin_unlock_irqrestore(&session->lock, flags); + goto done; + } + spin_unlock_irqrestore(&session->lock, flags); + + scsi_scan_target(&session->dev, 0, session->target_id, + SCAN_WILD_CARD, 1); +done: + atomic_dec(&ihost->nr_scans); +} + 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) +{ + struct Scsi_Host *shost = iscsi_session_to_shost(session); + struct iscsi_host *ihost = shost->shost_data; + 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); + /* + * Only do kernel scanning if the driver is properly hooked into + * the async scanning code (drivers like iscsi_tcp do login and + * scanning from userspace). + */ + if (shost->hostt->scan_finished) { + if (queue_work(ihost->scan_workq, &session->scan_work)) + atomic_inc(&ihost->nr_scans); + } +} 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); @@ -311,7 +442,7 @@ static int iscsi_unbind_session(struct iscsi_cls_session *session) struct Scsi_Host *shost = iscsi_session_to_shost(session); struct iscsi_host *ihost = shost->shost_data; - return queue_work(ihost->unbind_workq, &session->unbind_work); + return queue_work(ihost->scan_workq, &session->unbind_work); } struct iscsi_cls_session * @@ -327,10 +458,13 @@ 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); + INIT_WORK(&session->scan_work, iscsi_scan_session); + spin_lock_init(&session->lock); /* this is released in the dev's release function */ scsi_host_get(shost); @@ -443,15 +577,20 @@ 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); - iscsi_unbind_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->unbind_work); + + /* flush running scans */ + flush_workqueue(ihost->scan_workq); /* * If the session dropped while removing devices then we need to make * sure it is not blocked */ if (!cancel_delayed_work(&session->recovery_work)) flush_workqueue(iscsi_eh_timer_workq); - flush_workqueue(ihost->unbind_workq); /* hw iscsi may not have removed all connections from session */ err = device_for_each_child(&session->dev, NULL, @@ -660,16 +799,23 @@ 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 " @@ -1245,6 +1391,15 @@ 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) \ @@ -1471,6 +1626,7 @@ 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; |