[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 <James.Bottomley@SteelEye.com>
diff --git a/drivers/scsi/scsi_transport_fc.c b/drivers/scsi/scsi_transport_fc.c
index 8db6562..95c5478 100644
--- a/drivers/scsi/scsi_transport_fc.c
+++ b/drivers/scsi/scsi_transport_fc.c
@@ -34,6 +34,8 @@
#include <scsi/scsi_cmnd.h>
#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 @@
#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 @@
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->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(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->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(shost) = FC_TGTID_BIND_BY_WWPN;
+ fc_host->tgtid_bind_type = 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;
+ 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;
- fc_host_flags(shost) = 0;
- INIT_WORK(&fc_host_rport_del_work(shost), fc_shost_remove_rports, shost);
+ 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 @@
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 @@
}
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 @@
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 @@
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 @@
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 @@
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 @@
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 @@
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 @@
*/
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 @@
* 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 @@
}
if (match) {
- list_move_tail(&rport->peers,
- &fc_host_rports(shost));
+ list_move_tail(&rport->peers, &fc_host->rports);
break;
}
}
@@ -1574,15 +1754,17 @@
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 @@
}
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 @@
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 @@
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 @@
} 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 @@
* 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 @@
{
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 @@
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 @@
"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 @@
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 @@
* 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 @@
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 cf3fec8..5626225 100644
--- a/include/scsi/scsi_transport_fc.h
+++ b/include/scsi/scsi_transport_fc.h
@@ -202,12 +202,19 @@
/* 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 list_head rport_bindings;
u32 next_rport_number;
u32 next_target_id;
- u8 flags;
- struct work_struct rport_del_work;
+
+ /* 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;
};
-/* values for struct fc_host_attrs "flags" field: */
-#define FC_SHOST_RPORT_DEL_SCHEDULED 0x01
-
+#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 *)(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 @@
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;
