[SCSI] improved eh timeout handler
When a command runs into a timeout we need to send an 'ABORT TASK'
TMF. This is typically done by the 'eh_abort_handler' LLDD callback.
Conceptually, however, this function is a normal SCSI command, so
there is no need to enter the error handler.
This patch implements a new scsi_abort_command() function which
invokes an asynchronous function scsi_eh_abort_handler() to
abort the commands via the usual 'eh_abort_handler'.
If abort succeeds the command is either retried or terminated,
depending on the number of allowed retries. However, 'eh_eflags'
records the abort, so if the retry would fail again the
command is pushed onto the error handler without trying to
abort it (again); it'll be cleared up from SCSI EH.
[hare: smatch detected stray switch fixed]
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
index f2c5005..c3ab093 100644
--- a/drivers/scsi/hosts.c
+++ b/drivers/scsi/hosts.c
@@ -169,6 +169,7 @@
spin_unlock_irqrestore(shost->host_lock, flags);
scsi_autopm_get_host(shost);
+ flush_workqueue(shost->tmf_work_q);
scsi_forget_host(shost);
mutex_unlock(&shost->scan_mutex);
scsi_proc_host_rm(shost);
@@ -294,6 +295,8 @@
scsi_proc_hostdir_rm(shost->hostt);
+ if (shost->tmf_work_q)
+ destroy_workqueue(shost->tmf_work_q);
if (shost->ehandler)
kthread_stop(shost->ehandler);
if (shost->work_q)
@@ -360,7 +363,6 @@
INIT_LIST_HEAD(&shost->eh_cmd_q);
INIT_LIST_HEAD(&shost->starved_list);
init_waitqueue_head(&shost->host_wait);
-
mutex_init(&shost->scan_mutex);
/*
@@ -444,9 +446,19 @@
goto fail_kfree;
}
+ shost->tmf_work_q = alloc_workqueue("scsi_tmf_%d",
+ WQ_UNBOUND | WQ_MEM_RECLAIM,
+ 1, shost->host_no);
+ if (!shost->tmf_work_q) {
+ printk(KERN_WARNING "scsi%d: failed to create tmf workq\n",
+ shost->host_no);
+ goto fail_kthread;
+ }
scsi_proc_hostdir_add(shost->hostt);
return shost;
+ fail_kthread:
+ kthread_stop(shost->ehandler);
fail_kfree:
kfree(shost);
return NULL;