[SCSI] libsas: modify error handler to use scsi_eh_* functions

This patch adds an EH done queue to sas_ha, converts the error handling
strategy function and the sas_scsi_task_done functions in libsas to use
the scsi_eh_* commands for error'd commands, and adds checks for the
INITIATOR_ABORTED flag so that we do the right thing if a sas_task has
been aborted by the initiator.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

3 files changed, 33 insertions, 7 deletions

diff --git a/drivers/scsi/libsas/sas_init.c b/drivers/scsi/libsas/sas_init.c
index c836a237fb79..a2b479a65908 100644
--- a/drivers/scsi/libsas/sas_init.c
+++ b/drivers/scsi/libsas/sas_init.c
@@ -112,6 +112,8 @@ int sas_register_ha(struct sas_ha_struct *sas_ha)
                 }
         }
 
+        INIT_LIST_HEAD(&sas_ha->eh_done_q);
+
         return 0;
 
 Undo_ports:
diff --git a/drivers/scsi/libsas/sas_scsi_host.c b/drivers/scsi/libsas/sas_scsi_host.c
index e46e79355b77..6a97b07849b4 100644
--- a/drivers/scsi/libsas/sas_scsi_host.c
+++ b/drivers/scsi/libsas/sas_scsi_host.c
@@ -29,6 +29,7 @@
 #include <scsi/scsi_device.h>
 #include <scsi/scsi_tcq.h>
 #include <scsi/scsi.h>
+#include <scsi/scsi_eh.h>
 #include <scsi/scsi_transport.h>
 #include <scsi/scsi_transport_sas.h>
 #include "../scsi_sas_internal.h"
@@ -46,6 +47,7 @@ static void sas_scsi_task_done(struct sas_task *task)
 {
         struct task_status_struct *ts = &task->task_status;
         struct scsi_cmnd *sc = task->uldd_task;
+        struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(sc->device->host);
         unsigned ts_flags = task->task_state_flags;
         int hs = 0, stat = 0;
 
@@ -116,7 +118,7 @@ static void sas_scsi_task_done(struct sas_task *task)
         sas_free_task(task);
         /* This is very ugly but this is how SCSI Core works. */
         if (ts_flags & SAS_TASK_STATE_ABORTED)
-                scsi_finish_command(sc);
+                scsi_eh_finish_cmd(sc, &sas_ha->eh_done_q);
         else
                 sc->scsi_done(sc);
 }
@@ -307,6 +309,15 @@ static enum task_disposition sas_scsi_find_task(struct sas_task *task)
                 spin_unlock_irqrestore(&core->task_queue_lock, flags);
         }
 
+        spin_lock_irqsave(&task->task_state_lock, flags);
+        if (task->task_state_flags & SAS_TASK_INITIATOR_ABORTED) {
+                spin_unlock_irqrestore(&task->task_state_lock, flags);
+                SAS_DPRINTK("%s: task 0x%p already aborted\n",
+                            __FUNCTION__, task);
+                return TASK_IS_ABORTED;
+        }
+        spin_unlock_irqrestore(&task->task_state_lock, flags);
+
         for (i = 0; i < 5; i++) {
                 SAS_DPRINTK("%s: aborting task 0x%p\n", __FUNCTION__, task);
                 res = si->dft->lldd_abort_task(task);
@@ -409,13 +420,16 @@ Again:
         SAS_DPRINTK("going over list...\n");
         list_for_each_entry_safe(cmd, n, &error_q, eh_entry) {
                 struct sas_task *task = TO_SAS_TASK(cmd);
+                list_del_init(&cmd->eh_entry);
 
+                if (!task) {
+                        SAS_DPRINTK("%s: taskless cmd?!\n", __FUNCTION__);
+                        continue;
+                }
                 SAS_DPRINTK("trying to find task 0x%p\n", task);
-                list_del_init(&cmd->eh_entry);
                 res = sas_scsi_find_task(task);
 
                 cmd->eh_eflags = 0;
-                shost->host_failed--;
 
                 switch (res) {
                 case TASK_IS_DONE:
@@ -491,6 +505,7 @@ Again:
                 }
         }
 out:
+        scsi_eh_flush_done_q(&ha->eh_done_q);
         SAS_DPRINTK("--- Exit %s\n", __FUNCTION__);
         return;
 clear_q:
@@ -508,12 +523,18 @@ enum scsi_eh_timer_return sas_scsi_timed_out(struct scsi_cmnd *cmd)
         unsigned long flags;
 
         if (!task) {
-                SAS_DPRINTK("command 0x%p, task 0x%p, timed out: EH_HANDLED\n",
+                SAS_DPRINTK("command 0x%p, task 0x%p, gone: EH_HANDLED\n",
                             cmd, task);
                 return EH_HANDLED;
         }
 
         spin_lock_irqsave(&task->task_state_lock, flags);
+        if (task->task_state_flags & SAS_TASK_INITIATOR_ABORTED) {
+                spin_unlock_irqrestore(&task->task_state_lock, flags);
+                SAS_DPRINTK("command 0x%p, task 0x%p, aborted by initiator: "
+                            "EH_NOT_HANDLED\n", cmd, task);
+                return EH_NOT_HANDLED;
+        }
         if (task->task_state_flags & SAS_TASK_STATE_DONE) {
                 spin_unlock_irqrestore(&task->task_state_lock, flags);
                 SAS_DPRINTK("command 0x%p, task 0x%p, timed out: EH_HANDLED\n",
diff --git a/include/scsi/libsas.h b/include/scsi/libsas.h
index 9582e8401669..7bf2e8b9903c 100644
--- a/include/scsi/libsas.h
+++ b/include/scsi/libsas.h
@@ -338,6 +338,8 @@ struct sas_ha_struct {
         void (*notify_phy_event)(struct asd_sas_phy *, enum phy_event);
 
         void *lldd_ha;            /* not touched by sas class code */
+
+        struct list_head eh_done_q;
 };
 
 #define SHOST_TO_SAS_HA(_shost) (*(struct sas_ha_struct **)(_shost)->hostdata)
@@ -530,9 +532,10 @@ struct sas_task {
 
 
 
-#define SAS_TASK_STATE_PENDING  1
-#define SAS_TASK_STATE_DONE     2
-#define SAS_TASK_STATE_ABORTED  4
+#define SAS_TASK_STATE_PENDING      1
+#define SAS_TASK_STATE_DONE         2
+#define SAS_TASK_STATE_ABORTED      4
+#define SAS_TASK_INITIATOR_ABORTED  8
 
 static inline struct sas_task *sas_alloc_task(gfp_t flags)
 {