From: James Smart Date: Mon, 10 Apr 2006 14:14:05 +0000 (-0400) Subject: [SCSI] FC transport: fixes for workq deadlocks X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=aedf349773e5877d716a89368d512b9baa3e8c7b;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git [SCSI] FC transport: fixes for workq deadlocks As previously reported via Michael Reed, the FC transport took a hit in 2.6.15 (perhaps a little earlier) when we solved a recursion error. There are 2 deadlocks occurring: - With scan and the delete items sharing the same workq, flushing the workq for the delete code was getting it stalled behind a very long running scan code path. - There's a deadlock where scsi_remove_target() has to sit behind scsi_scan_target() due to contention over the scan_lock(). This patch resolves the 1st deadlock and significantly reduces the odds of the second. So far, we have only replicated the 2nd deadlock on a highly-parallel SMP system. More on the 2nd deadlock in a following email. This patch reworks the transport to: - Only use the scsi host workq for scanning - Use 2 other workq's internally. One for deletions, the other for scheduled deletions. Originally, we tried this with a single workq, but the occassional flushes of the scheduled queues was hitting the second deadlock with a slightly higher frequency. In the future, we'll look at the LLDD's and the transport to see if we can get rid of this extra overhead. - When moving to the other workq's we tightened up some object states and some lock handling. - Properly syncs adds/deletes - minor code cleanups - directly reference fc_host_attrs, rather than through attribute macros - flush the right workq on delayed work cancel failures. Large kudos to Michael Reed who has been working this issue for the last month. Signed-off-by: James Bottomley --- diff --git a/drivers/scsi/scsi_transport_fc.c b/drivers/scsi/scsi_transport_fc.c index 8db656214b5c..95c5478dcdfd 100644 --- a/drivers/scsi/scsi_transport_fc.c +++ b/drivers/scsi/scsi_transport_fc.c @@ -34,6 +34,8 @@ #include #include "scsi_priv.h" +static int fc_queue_work(struct Scsi_Host *, struct work_struct *); + /* * Redefine so that we can have same named attributes in the * sdev/starget/host objects. @@ -213,10 +215,8 @@ fc_bitfield_name_search(remote_port_roles, fc_remote_port_role_names) #define FC_MGMTSRVR_PORTID 0x00000a -static void fc_shost_remove_rports(void *data); static void fc_timeout_deleted_rport(void *data); static void fc_scsi_scan_rport(void *data); -static void fc_rport_terminate(struct fc_rport *rport); /* * Attribute counts pre object type... @@ -288,42 +288,58 @@ static int fc_host_setup(struct transport_container *tc, struct device *dev, struct class_device *cdev) { struct Scsi_Host *shost = dev_to_shost(dev); + struct fc_host_attrs *fc_host = shost_to_fc_host(shost); /* * Set default values easily detected by the midlayer as * failure cases. The scsi lldd is responsible for initializing * all transport attributes to valid values per host. */ - fc_host_node_name(shost) = -1; - fc_host_port_name(shost) = -1; - fc_host_permanent_port_name(shost) = -1; - fc_host_supported_classes(shost) = FC_COS_UNSPECIFIED; - memset(fc_host_supported_fc4s(shost), 0, - sizeof(fc_host_supported_fc4s(shost))); - memset(fc_host_symbolic_name(shost), 0, - sizeof(fc_host_symbolic_name(shost))); - fc_host_supported_speeds(shost) = FC_PORTSPEED_UNKNOWN; - fc_host_maxframe_size(shost) = -1; - memset(fc_host_serial_number(shost), 0, - sizeof(fc_host_serial_number(shost))); - - fc_host_port_id(shost) = -1; - fc_host_port_type(shost) = FC_PORTTYPE_UNKNOWN; - fc_host_port_state(shost) = FC_PORTSTATE_UNKNOWN; - memset(fc_host_active_fc4s(shost), 0, - sizeof(fc_host_active_fc4s(shost))); - fc_host_speed(shost) = FC_PORTSPEED_UNKNOWN; - fc_host_fabric_name(shost) = -1; - - fc_host_tgtid_bind_type(shost) = FC_TGTID_BIND_BY_WWPN; - - INIT_LIST_HEAD(&fc_host_rports(shost)); - INIT_LIST_HEAD(&fc_host_rport_bindings(shost)); - fc_host_next_rport_number(shost) = 0; - fc_host_next_target_id(shost) = 0; - - fc_host_flags(shost) = 0; - INIT_WORK(&fc_host_rport_del_work(shost), fc_shost_remove_rports, shost); + fc_host->node_name = -1; + fc_host->port_name = -1; + fc_host->permanent_port_name = -1; + fc_host->supported_classes = FC_COS_UNSPECIFIED; + memset(fc_host->supported_fc4s, 0, + sizeof(fc_host->supported_fc4s)); + memset(fc_host->symbolic_name, 0, + sizeof(fc_host->symbolic_name)); + fc_host->supported_speeds = FC_PORTSPEED_UNKNOWN; + fc_host->maxframe_size = -1; + memset(fc_host->serial_number, 0, + sizeof(fc_host->serial_number)); + + fc_host->port_id = -1; + fc_host->port_type = FC_PORTTYPE_UNKNOWN; + fc_host->port_state = FC_PORTSTATE_UNKNOWN; + memset(fc_host->active_fc4s, 0, + sizeof(fc_host->active_fc4s)); + fc_host->speed = FC_PORTSPEED_UNKNOWN; + fc_host->fabric_name = -1; + + fc_host->tgtid_bind_type = FC_TGTID_BIND_BY_WWPN; + + INIT_LIST_HEAD(&fc_host->rports); + INIT_LIST_HEAD(&fc_host->rport_bindings); + fc_host->next_rport_number = 0; + fc_host->next_target_id = 0; + + snprintf(fc_host->work_q_name, KOBJ_NAME_LEN, "fc_wq_%d", + shost->host_no); + fc_host->work_q = create_singlethread_workqueue( + fc_host->work_q_name); + if (!fc_host->work_q) + return -ENOMEM; + + snprintf(fc_host->devloss_work_q_name, KOBJ_NAME_LEN, "fc_dl_%d", + shost->host_no); + fc_host->devloss_work_q = create_singlethread_workqueue( + fc_host->devloss_work_q_name); + if (!fc_host->devloss_work_q) { + destroy_workqueue(fc_host->work_q); + fc_host->work_q = NULL; + return -ENOMEM; + } + return 0; } @@ -879,9 +895,9 @@ store_fc_private_host_tgtid_bind_type(struct class_device *cdev, while (!list_empty(&fc_host_rport_bindings(shost))) { get_list_head_entry(rport, &fc_host_rport_bindings(shost), peers); - spin_unlock_irqrestore(shost->host_lock, flags); - fc_rport_terminate(rport); - spin_lock_irqsave(shost->host_lock, flags); + list_del(&rport->peers); + rport->port_state = FC_PORTSTATE_DELETED; + fc_queue_work(shost, &rport->rport_delete_work); } spin_unlock_irqrestore(shost->host_lock, flags); } @@ -1262,6 +1278,90 @@ void fc_release_transport(struct scsi_transport_template *t) } EXPORT_SYMBOL(fc_release_transport); +/** + * fc_queue_work - Queue work to the fc_host workqueue. + * @shost: Pointer to Scsi_Host bound to fc_host. + * @work: Work to queue for execution. + * + * Return value: + * 0 on success / != 0 for error + **/ +static int +fc_queue_work(struct Scsi_Host *shost, struct work_struct *work) +{ + if (unlikely(!fc_host_work_q(shost))) { + printk(KERN_ERR + "ERROR: FC host '%s' attempted to queue work, " + "when no workqueue created.\n", shost->hostt->name); + dump_stack(); + + return -EINVAL; + } + + return queue_work(fc_host_work_q(shost), work); +} + +/** + * fc_flush_work - Flush a fc_host's workqueue. + * @shost: Pointer to Scsi_Host bound to fc_host. + **/ +static void +fc_flush_work(struct Scsi_Host *shost) +{ + if (!fc_host_work_q(shost)) { + printk(KERN_ERR + "ERROR: FC host '%s' attempted to flush work, " + "when no workqueue created.\n", shost->hostt->name); + dump_stack(); + return; + } + + flush_workqueue(fc_host_work_q(shost)); +} + +/** + * fc_queue_devloss_work - Schedule work for the fc_host devloss workqueue. + * @shost: Pointer to Scsi_Host bound to fc_host. + * @work: Work to queue for execution. + * @delay: jiffies to delay the work queuing + * + * Return value: + * 0 on success / != 0 for error + **/ +static int +fc_queue_devloss_work(struct Scsi_Host *shost, struct work_struct *work, + unsigned long delay) +{ + if (unlikely(!fc_host_devloss_work_q(shost))) { + printk(KERN_ERR + "ERROR: FC host '%s' attempted to queue work, " + "when no workqueue created.\n", shost->hostt->name); + dump_stack(); + + return -EINVAL; + } + + return queue_delayed_work(fc_host_devloss_work_q(shost), work, delay); +} + +/** + * fc_flush_devloss - Flush a fc_host's devloss workqueue. + * @shost: Pointer to Scsi_Host bound to fc_host. + **/ +static void +fc_flush_devloss(struct Scsi_Host *shost) +{ + if (!fc_host_devloss_work_q(shost)) { + printk(KERN_ERR + "ERROR: FC host '%s' attempted to flush work, " + "when no workqueue created.\n", shost->hostt->name); + dump_stack(); + return; + } + + flush_workqueue(fc_host_devloss_work_q(shost)); +} + /** * fc_remove_host - called to terminate any fc_transport-related elements @@ -1283,36 +1383,103 @@ void fc_remove_host(struct Scsi_Host *shost) { struct fc_rport *rport, *next_rport; + struct workqueue_struct *work_q; + struct fc_host_attrs *fc_host = shost_to_fc_host(shost); /* Remove any remote ports */ list_for_each_entry_safe(rport, next_rport, - &fc_host_rports(shost), peers) - fc_rport_terminate(rport); + &fc_host->rports, peers) { + list_del(&rport->peers); + rport->port_state = FC_PORTSTATE_DELETED; + fc_queue_work(shost, &rport->rport_delete_work); + } + list_for_each_entry_safe(rport, next_rport, - &fc_host_rport_bindings(shost), peers) - fc_rport_terminate(rport); + &fc_host->rport_bindings, peers) { + list_del(&rport->peers); + rport->port_state = FC_PORTSTATE_DELETED; + fc_queue_work(shost, &rport->rport_delete_work); + } + + /* flush all scan work items */ + scsi_flush_work(shost); + + /* flush all stgt delete, and rport delete work items, then kill it */ + if (fc_host->work_q) { + work_q = fc_host->work_q; + fc_host->work_q = NULL; + destroy_workqueue(work_q); + } + + /* flush all devloss work items, then kill it */ + if (fc_host->devloss_work_q) { + work_q = fc_host->devloss_work_q; + fc_host->devloss_work_q = NULL; + destroy_workqueue(work_q); + } } EXPORT_SYMBOL(fc_remove_host); -/* - * fc_rport_tgt_remove - Removes the scsi target on the remote port - * @rport: The remote port to be operated on - */ + +/** + * fc_starget_delete - called to delete the scsi decendents of an rport + * (target and all sdevs) + * + * @data: remote port to be operated on. + **/ static void -fc_rport_tgt_remove(struct fc_rport *rport) +fc_starget_delete(void *data) { + struct fc_rport *rport = (struct fc_rport *)data; struct Scsi_Host *shost = rport_to_shost(rport); + unsigned long flags; scsi_target_unblock(&rport->dev); - /* Stop anything on the workq */ - if (!cancel_delayed_work(&rport->dev_loss_work)) - flush_scheduled_work(); - scsi_flush_work(shost); + spin_lock_irqsave(shost->host_lock, flags); + if (rport->flags & FC_RPORT_DEVLOSS_PENDING) { + spin_unlock_irqrestore(shost->host_lock, flags); + if (!cancel_delayed_work(&rport->dev_loss_work)) + fc_flush_devloss(shost); + spin_lock_irqsave(shost->host_lock, flags); + rport->flags &= ~FC_RPORT_DEVLOSS_PENDING; + } + spin_unlock_irqrestore(shost->host_lock, flags); scsi_remove_target(&rport->dev); } + +/** + * fc_rport_final_delete - finish rport termination and delete it. + * + * @data: remote port to be deleted. + **/ +static void +fc_rport_final_delete(void *data) +{ + struct fc_rport *rport = (struct fc_rport *)data; + struct device *dev = &rport->dev; + struct Scsi_Host *shost = rport_to_shost(rport); + + /* Delete SCSI target and sdevs */ + if (rport->scsi_target_id != -1) + fc_starget_delete(data); + + /* + * if a scan is pending, flush the SCSI Host work_q so that + * that we can reclaim the rport scan work element. + */ + if (rport->flags & FC_RPORT_SCAN_PENDING) + scsi_flush_work(shost); + + transport_remove_device(dev); + device_del(dev); + transport_destroy_device(dev); + put_device(&shost->shost_gendev); +} + + /** * fc_rport_create - allocates and creates a remote FC port. * @shost: scsi host the remote port is connected to. @@ -1330,8 +1497,7 @@ struct fc_rport * fc_rport_create(struct Scsi_Host *shost, int channel, struct fc_rport_identifiers *ids) { - struct fc_host_attrs *fc_host = - (struct fc_host_attrs *)shost->shost_data; + struct fc_host_attrs *fc_host = shost_to_fc_host(shost); struct fc_internal *fci = to_fc_internal(shost->transportt); struct fc_rport *rport; struct device *dev; @@ -1360,6 +1526,8 @@ fc_rport_create(struct Scsi_Host *shost, int channel, INIT_WORK(&rport->dev_loss_work, fc_timeout_deleted_rport, rport); INIT_WORK(&rport->scan_work, fc_scsi_scan_rport, rport); + INIT_WORK(&rport->stgt_delete_work, fc_starget_delete, rport); + INIT_WORK(&rport->rport_delete_work, fc_rport_final_delete, rport); spin_lock_irqsave(shost->host_lock, flags); @@ -1368,7 +1536,7 @@ fc_rport_create(struct Scsi_Host *shost, int channel, rport->scsi_target_id = fc_host->next_target_id++; else rport->scsi_target_id = -1; - list_add_tail(&rport->peers, &fc_host_rports(shost)); + list_add_tail(&rport->peers, &fc_host->rports); get_device(&shost->shost_gendev); spin_unlock_irqrestore(shost->host_lock, flags); @@ -1389,9 +1557,11 @@ fc_rport_create(struct Scsi_Host *shost, int channel, transport_add_device(dev); transport_configure_device(dev); - if (rport->roles & FC_RPORT_ROLE_FCP_TARGET) + if (rport->roles & FC_RPORT_ROLE_FCP_TARGET) { /* initiate a scan of the target */ + rport->flags |= FC_RPORT_SCAN_PENDING; scsi_queue_work(shost, &rport->scan_work); + } return rport; @@ -1451,10 +1621,14 @@ fc_remote_port_add(struct Scsi_Host *shost, int channel, struct fc_rport_identifiers *ids) { struct fc_internal *fci = to_fc_internal(shost->transportt); + struct fc_host_attrs *fc_host = shost_to_fc_host(shost); struct fc_rport *rport; unsigned long flags; int match = 0; + /* ensure any stgt delete functions are done */ + fc_flush_work(shost); + /* * Search the list of "active" rports, for an rport that has been * deleted, but we've held off the real delete while the target @@ -1462,12 +1636,12 @@ fc_remote_port_add(struct Scsi_Host *shost, int channel, */ spin_lock_irqsave(shost->host_lock, flags); - list_for_each_entry(rport, &fc_host_rports(shost), peers) { + list_for_each_entry(rport, &fc_host->rports, peers) { if ((rport->port_state == FC_PORTSTATE_BLOCKED) && (rport->channel == channel)) { - switch (fc_host_tgtid_bind_type(shost)) { + switch (fc_host->tgtid_bind_type) { case FC_TGTID_BIND_BY_WWPN: case FC_TGTID_BIND_NONE: if (rport->port_name == ids->port_name) @@ -1521,27 +1695,34 @@ fc_remote_port_add(struct Scsi_Host *shost, int channel, * transaction. */ if (!cancel_delayed_work(work)) - flush_scheduled_work(); + fc_flush_devloss(shost); + + spin_lock_irqsave(shost->host_lock, flags); + + rport->flags &= ~FC_RPORT_DEVLOSS_PENDING; /* initiate a scan of the target */ + rport->flags |= FC_RPORT_SCAN_PENDING; scsi_queue_work(shost, &rport->scan_work); + spin_unlock_irqrestore(shost->host_lock, flags); + return rport; } } } /* Search the bindings array */ - if (fc_host_tgtid_bind_type(shost) != FC_TGTID_BIND_NONE) { + if (fc_host->tgtid_bind_type != FC_TGTID_BIND_NONE) { /* search for a matching consistent binding */ - list_for_each_entry(rport, &fc_host_rport_bindings(shost), + list_for_each_entry(rport, &fc_host->rport_bindings, peers) { if (rport->channel != channel) continue; - switch (fc_host_tgtid_bind_type(shost)) { + switch (fc_host->tgtid_bind_type) { case FC_TGTID_BIND_BY_WWPN: if (rport->port_name == ids->port_name) match = 1; @@ -1559,8 +1740,7 @@ fc_remote_port_add(struct Scsi_Host *shost, int channel, } if (match) { - list_move_tail(&rport->peers, - &fc_host_rports(shost)); + list_move_tail(&rport->peers, &fc_host->rports); break; } } @@ -1574,15 +1754,17 @@ fc_remote_port_add(struct Scsi_Host *shost, int channel, rport->roles = ids->roles; rport->port_state = FC_PORTSTATE_ONLINE; - spin_unlock_irqrestore(shost->host_lock, flags); - if (fci->f->dd_fcrport_size) memset(rport->dd_data, 0, fci->f->dd_fcrport_size); - if (rport->roles & FC_RPORT_ROLE_FCP_TARGET) + if (rport->roles & FC_RPORT_ROLE_FCP_TARGET) { /* initiate a scan of the target */ + rport->flags |= FC_RPORT_SCAN_PENDING; scsi_queue_work(shost, &rport->scan_work); + } + + spin_unlock_irqrestore(shost->host_lock, flags); return rport; } @@ -1597,30 +1779,6 @@ fc_remote_port_add(struct Scsi_Host *shost, int channel, } EXPORT_SYMBOL(fc_remote_port_add); -/* - * fc_rport_terminate - this routine tears down and deallocates a remote port. - * @rport: The remote port to be terminated - * - * Notes: - * This routine assumes no locks are held on entry. - */ -static void -fc_rport_terminate(struct fc_rport *rport) -{ - struct Scsi_Host *shost = rport_to_shost(rport); - struct device *dev = &rport->dev; - unsigned long flags; - - fc_rport_tgt_remove(rport); - - transport_remove_device(dev); - device_del(dev); - transport_destroy_device(dev); - spin_lock_irqsave(shost->host_lock, flags); - list_del(&rport->peers); - spin_unlock_irqrestore(shost->host_lock, flags); - put_device(&shost->shost_gendev); -} /** * fc_remote_port_delete - notifies the fc transport that a remote @@ -1675,20 +1833,39 @@ fc_rport_terminate(struct fc_rport *rport) void fc_remote_port_delete(struct fc_rport *rport) { + struct Scsi_Host *shost = rport_to_shost(rport); int timeout = rport->dev_loss_tmo; + unsigned long flags; + + /* + * No need to flush the fc_host work_q's, as all adds are synchronous. + * + * We do need to reclaim the rport scan work element, so eventually + * (in fc_rport_final_delete()) we'll flush the scsi host work_q if + * there's still a scan pending. + */ + + spin_lock_irqsave(shost->host_lock, flags); /* If no scsi target id mapping, delete it */ if (rport->scsi_target_id == -1) { - fc_rport_terminate(rport); + list_del(&rport->peers); + rport->port_state = FC_PORTSTATE_DELETED; + fc_queue_work(shost, &rport->rport_delete_work); + spin_unlock_irqrestore(shost->host_lock, flags); return; } + rport->port_state = FC_PORTSTATE_BLOCKED; + + rport->flags |= FC_RPORT_DEVLOSS_PENDING; + + spin_unlock_irqrestore(shost->host_lock, flags); + scsi_target_block(&rport->dev); /* cap the length the devices can be blocked until they are deleted */ - schedule_delayed_work(&rport->dev_loss_work, timeout * HZ); - - rport->port_state = FC_PORTSTATE_BLOCKED; + fc_queue_devloss_work(shost, &rport->dev_loss_work, timeout * HZ); } EXPORT_SYMBOL(fc_remote_port_delete); @@ -1716,8 +1893,7 @@ void fc_remote_port_rolechg(struct fc_rport *rport, u32 roles) { struct Scsi_Host *shost = rport_to_shost(rport); - struct fc_host_attrs *fc_host = - (struct fc_host_attrs *)shost->shost_data; + struct fc_host_attrs *fc_host = shost_to_fc_host(shost); unsigned long flags; int create = 0; @@ -1729,10 +1905,11 @@ fc_remote_port_rolechg(struct fc_rport *rport, u32 roles) } else if (!(rport->roles & FC_RPORT_ROLE_FCP_TARGET)) create = 1; } - spin_unlock_irqrestore(shost->host_lock, flags); rport->roles = roles; + spin_unlock_irqrestore(shost->host_lock, flags); + if (create) { /* * There may have been a delete timer running on the @@ -1747,10 +1924,20 @@ fc_remote_port_rolechg(struct fc_rport *rport, u32 roles) * transaction. */ if (!cancel_delayed_work(&rport->dev_loss_work)) - flush_scheduled_work(); + fc_flush_devloss(shost); + + spin_lock_irqsave(shost->host_lock, flags); + rport->flags &= ~FC_RPORT_DEVLOSS_PENDING; + spin_unlock_irqrestore(shost->host_lock, flags); + + /* ensure any stgt delete functions are done */ + fc_flush_work(shost); /* initiate a scan of the target */ + spin_lock_irqsave(shost->host_lock, flags); + rport->flags |= FC_RPORT_SCAN_PENDING; scsi_queue_work(shost, &rport->scan_work); + spin_unlock_irqrestore(shost->host_lock, flags); } } EXPORT_SYMBOL(fc_remote_port_rolechg); @@ -1767,22 +1954,24 @@ fc_timeout_deleted_rport(void *data) { struct fc_rport *rport = (struct fc_rport *)data; struct Scsi_Host *shost = rport_to_shost(rport); + struct fc_host_attrs *fc_host = shost_to_fc_host(shost); unsigned long flags; spin_lock_irqsave(shost->host_lock, flags); + rport->flags &= ~FC_RPORT_DEVLOSS_PENDING; + /* - * If the port is ONLINE, then it came back, but was no longer an - * FCP target. Thus we need to tear down the scsi_target on it. + * If the port is ONLINE, then it came back. Validate it's still an + * FCP target. If not, tear down the scsi_target on it. */ - if (rport->port_state == FC_PORTSTATE_ONLINE) { - spin_unlock_irqrestore(shost->host_lock, flags); - + if ((rport->port_state == FC_PORTSTATE_ONLINE) && + !(rport->roles & FC_RPORT_ROLE_FCP_TARGET)) { dev_printk(KERN_ERR, &rport->dev, - "blocked FC remote port time out: removing target\n"); - - fc_rport_tgt_remove(rport); - + "blocked FC remote port time out: no longer" + " a FCP target, removing starget\n"); + fc_queue_work(shost, &rport->stgt_delete_work); + spin_unlock_irqrestore(shost->host_lock, flags); return; } @@ -1793,11 +1982,13 @@ fc_timeout_deleted_rport(void *data) return; } - if (fc_host_tgtid_bind_type(shost) == FC_TGTID_BIND_NONE) { - spin_unlock_irqrestore(shost->host_lock, flags); + if (fc_host->tgtid_bind_type == FC_TGTID_BIND_NONE) { + list_del(&rport->peers); + rport->port_state = FC_PORTSTATE_DELETED; dev_printk(KERN_ERR, &rport->dev, "blocked FC remote port time out: removing target\n"); - fc_rport_terminate(rport); + fc_queue_work(shost, &rport->rport_delete_work); + spin_unlock_irqrestore(shost->host_lock, flags); return; } @@ -1805,7 +1996,7 @@ fc_timeout_deleted_rport(void *data) "blocked FC remote port time out: removing target and " "saving binding\n"); - list_move_tail(&rport->peers, &fc_host_rport_bindings(shost)); + list_move_tail(&rport->peers, &fc_host->rport_bindings); /* * Note: We do not remove or clear the hostdata area. This allows @@ -1819,10 +2010,10 @@ fc_timeout_deleted_rport(void *data) rport->maxframe_size = -1; rport->supported_classes = FC_COS_UNSPECIFIED; rport->roles = FC_RPORT_ROLE_UNKNOWN; - rport->port_state = FC_PORTSTATE_DELETED; + rport->port_state = FC_PORTSTATE_NOTPRESENT; /* remove the identifiers that aren't used in the consisting binding */ - switch (fc_host_tgtid_bind_type(shost)) { + switch (fc_host->tgtid_bind_type) { case FC_TGTID_BIND_BY_WWPN: rport->node_name = -1; rport->port_id = -1; @@ -1843,17 +2034,8 @@ fc_timeout_deleted_rport(void *data) * As this only occurs if the remote port (scsi target) * went away and didn't come back - we'll remove * all attached scsi devices. - * - * We'll schedule the shost work item to perform the actual removal - * to avoid recursion in the different flush calls if we perform - * the removal in each target - and there are lots of targets - * whose timeouts fire at the same time. */ - - if ( !(fc_host_flags(shost) & FC_SHOST_RPORT_DEL_SCHEDULED)) { - fc_host_flags(shost) |= FC_SHOST_RPORT_DEL_SCHEDULED; - scsi_queue_work(shost, &fc_host_rport_del_work(shost)); - } + fc_queue_work(shost, &rport->stgt_delete_work); spin_unlock_irqrestore(shost->host_lock, flags); } @@ -1870,44 +2052,18 @@ static void fc_scsi_scan_rport(void *data) { struct fc_rport *rport = (struct fc_rport *)data; - - scsi_target_unblock(&rport->dev); - scsi_scan_target(&rport->dev, rport->channel, rport->scsi_target_id, - SCAN_WILD_CARD, 1); -} - - -/** - * fc_shost_remove_rports - called to remove all rports that are marked - * as in a deleted (not connected) state. - * - * @data: shost whose rports are to be looked at - **/ -static void -fc_shost_remove_rports(void *data) -{ - struct Scsi_Host *shost = (struct Scsi_Host *)data; - struct fc_rport *rport, *next_rport; + struct Scsi_Host *shost = rport_to_shost(rport); unsigned long flags; - spin_lock_irqsave(shost->host_lock, flags); - while (fc_host_flags(shost) & FC_SHOST_RPORT_DEL_SCHEDULED) { - - fc_host_flags(shost) &= ~FC_SHOST_RPORT_DEL_SCHEDULED; - -restart_search: - list_for_each_entry_safe(rport, next_rport, - &fc_host_rport_bindings(shost), peers) { - if (rport->port_state == FC_PORTSTATE_DELETED) { - rport->port_state = FC_PORTSTATE_NOTPRESENT; - spin_unlock_irqrestore(shost->host_lock, flags); - fc_rport_tgt_remove(rport); - spin_lock_irqsave(shost->host_lock, flags); - goto restart_search; - } - } - + if ((rport->port_state == FC_PORTSTATE_ONLINE) && + (rport->roles & FC_RPORT_ROLE_FCP_TARGET)) { + scsi_target_unblock(&rport->dev); + scsi_scan_target(&rport->dev, rport->channel, + rport->scsi_target_id, SCAN_WILD_CARD, 1); } + + spin_lock_irqsave(shost->host_lock, flags); + rport->flags &= ~FC_RPORT_SCAN_PENDING; spin_unlock_irqrestore(shost->host_lock, flags); } diff --git a/include/scsi/scsi_transport_fc.h b/include/scsi/scsi_transport_fc.h index cf3fec8be1e3..5626225bd3ae 100644 --- a/include/scsi/scsi_transport_fc.h +++ b/include/scsi/scsi_transport_fc.h @@ -202,12 +202,19 @@ struct fc_rport { /* aka fc_starget_attrs */ /* internal data */ unsigned int channel; u32 number; + u8 flags; struct list_head peers; struct device dev; struct work_struct dev_loss_work; struct work_struct scan_work; + struct work_struct stgt_delete_work; + struct work_struct rport_delete_work; } __attribute__((aligned(sizeof(unsigned long)))); +/* bit field values for struct fc_rport "flags" field: */ +#define FC_RPORT_DEVLOSS_PENDING 0x01 +#define FC_RPORT_SCAN_PENDING 0x02 + #define dev_to_rport(d) \ container_of(d, struct fc_rport, dev) #define transport_class_to_rport(classdev) \ @@ -327,13 +334,16 @@ struct fc_host_attrs { struct list_head rport_bindings; u32 next_rport_number; u32 next_target_id; - u8 flags; - struct work_struct rport_del_work; -}; -/* values for struct fc_host_attrs "flags" field: */ -#define FC_SHOST_RPORT_DEL_SCHEDULED 0x01 + /* work queues for rport state manipulation */ + char work_q_name[KOBJ_NAME_LEN]; + struct workqueue_struct *work_q; + char devloss_work_q_name[KOBJ_NAME_LEN]; + struct workqueue_struct *devloss_work_q; +}; +#define shost_to_fc_host(x) \ + ((struct fc_host_attrs *)(x)->shost_data) #define fc_host_node_name(x) \ (((struct fc_host_attrs *)(x)->shost_data)->node_name) @@ -375,10 +385,14 @@ struct fc_host_attrs { (((struct fc_host_attrs *)(x)->shost_data)->next_rport_number) #define fc_host_next_target_id(x) \ (((struct fc_host_attrs *)(x)->shost_data)->next_target_id) -#define fc_host_flags(x) \ - (((struct fc_host_attrs *)(x)->shost_data)->flags) -#define fc_host_rport_del_work(x) \ - (((struct fc_host_attrs *)(x)->shost_data)->rport_del_work) +#define fc_host_work_q_name(x) \ + (((struct fc_host_attrs *)(x)->shost_data)->work_q_name) +#define fc_host_work_q(x) \ + (((struct fc_host_attrs *)(x)->shost_data)->work_q) +#define fc_host_devloss_work_q_name(x) \ + (((struct fc_host_attrs *)(x)->shost_data)->devloss_work_q_name) +#define fc_host_devloss_work_q(x) \ + (((struct fc_host_attrs *)(x)->shost_data)->devloss_work_q) /* The functions by which the transport class and the driver communicate */ @@ -461,10 +475,15 @@ fc_remote_port_chkready(struct fc_rport *rport) switch (rport->port_state) { case FC_PORTSTATE_ONLINE: - result = 0; + if (rport->roles & FC_RPORT_ROLE_FCP_TARGET) + result = 0; + else if (rport->flags & FC_RPORT_DEVLOSS_PENDING) + result = DID_IMM_RETRY << 16; + else + result = DID_NO_CONNECT << 16; break; case FC_PORTSTATE_BLOCKED: - result = DID_BUS_BUSY << 16; + result = DID_IMM_RETRY << 16; break; default: result = DID_NO_CONNECT << 16;