[SCSI] aic79xx: remove qfrozen

This patch removes the need for platform_data->qfrozen.
We're now using complete() instead of semaphores thus
simplifying ahd_freeze_simq() quite a lot.
This also fixes some deadlocks in the recovery code (again).

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

2 files changed, 27 insertions, 82 deletions

diff --git a/drivers/scsi/aic7xxx/aic79xx_osm.c b/drivers/scsi/aic7xxx/aic79xx_osm.c
index 7254ea535a16..fc393bd95f4a 100644
--- a/drivers/scsi/aic7xxx/aic79xx_osm.c
+++ b/drivers/scsi/aic7xxx/aic79xx_osm.c
@@ -373,7 +373,6 @@ static void ahd_linux_handle_scsi_status(struct ahd_softc *,
                                          struct scb *);
 static void ahd_linux_queue_cmd_complete(struct ahd_softc *ahd,
                                          struct scsi_cmnd *cmd);
-static void ahd_linux_sem_timeout(u_long arg);
 static int  ahd_linux_queue_recovery_cmd(struct scsi_cmnd *cmd, scb_flag flag);
 static void ahd_linux_initialize_scsi_bus(struct ahd_softc *ahd);
 static u_int ahd_linux_user_tagdepth(struct ahd_softc *ahd,
@@ -453,18 +452,13 @@ ahd_linux_queue(struct scsi_cmnd * cmd, void (*scsi_done) (struct scsi_cmnd *))
         struct   ahd_softc *ahd;
         struct   ahd_linux_device *dev = scsi_transport_device_data(cmd->device);
         int rtn = SCSI_MLQUEUE_HOST_BUSY;
-        unsigned long flags;
 
         ahd = *(struct ahd_softc **)cmd->device->host->hostdata;
 
-        ahd_lock(ahd, &flags);
-        if (ahd->platform_data->qfrozen == 0) {
-                cmd->scsi_done = scsi_done;
-                cmd->result = CAM_REQ_INPROG << 16;
-                rtn = ahd_linux_run_command(ahd, dev, cmd);
+        cmd->scsi_done = scsi_done;
+        cmd->result = CAM_REQ_INPROG << 16;
+        rtn = ahd_linux_run_command(ahd, dev, cmd);
 
-        }
-        ahd_unlock(ahd, &flags);
         return rtn;
 }
 
@@ -682,7 +676,6 @@ static int
 ahd_linux_bus_reset(struct scsi_cmnd *cmd)
 {
         struct ahd_softc *ahd;
-        u_long s;
         int    found;
 
         ahd = *(struct ahd_softc **)cmd->device->host->hostdata;
@@ -691,10 +684,8 @@ ahd_linux_bus_reset(struct scsi_cmnd *cmd)
                 printf("%s: Bus reset called for cmd %p\n",
                        ahd_name(ahd), cmd);
 #endif
-        ahd_lock(ahd, &s);
         found = ahd_reset_channel(ahd, scmd_channel(cmd) + 'A',
                                   /*initiate reset*/TRUE);
-        ahd_unlock(ahd, &s);
 
         if (bootverbose)
                 printf("%s: SCSI bus reset delivered. "
@@ -1194,7 +1185,6 @@ ahd_platform_alloc(struct ahd_softc *ahd, void *platform_arg)
         memset(ahd->platform_data, 0, sizeof(struct ahd_platform_data));
         ahd->platform_data->irq = AHD_LINUX_NOIRQ;
         ahd_lockinit(ahd);
-        init_MUTEX_LOCKED(&ahd->platform_data->eh_sem);
         ahd->seltime = (aic79xx_seltime & 0x3) << 4;
         return (0);
 }
@@ -1443,6 +1433,9 @@ ahd_linux_run_command(struct ahd_softc *ahd, struct ahd_linux_device *dev,
         struct   ahd_tmode_tstate *tstate;
         u_int    col_idx;
         uint16_t mask;
+        unsigned long flags;
+
+        ahd_lock(ahd, &flags);
 
         /*
          * Get an scb to use.
@@ -1458,6 +1451,7 @@ ahd_linux_run_command(struct ahd_softc *ahd, struct ahd_linux_device *dev,
         }
         if ((scb = ahd_get_scb(ahd, col_idx)) == NULL) {
                 ahd->flags |= AHD_RESOURCE_SHORTAGE;
+                ahd_unlock(ahd, &flags);
                 return SCSI_MLQUEUE_HOST_BUSY;
         }
 
@@ -1583,6 +1577,8 @@ ahd_linux_run_command(struct ahd_softc *ahd, struct ahd_linux_device *dev,
         scb->flags |= SCB_ACTIVE;
         ahd_queue_scb(ahd, scb);
 
+        ahd_unlock(ahd, &flags);
+
         return 0;
 }
 
@@ -1618,7 +1614,6 @@ ahd_send_async(struct ahd_softc *ahd, char channel,
         {
                 char    buf[80];
                 struct  scsi_target *starget;
-                struct  ahd_linux_target *targ;
                 struct  info_str info;
                 struct  ahd_initiator_tinfo *tinfo;
                 struct  ahd_tmode_tstate *tstate;
@@ -1651,7 +1646,6 @@ ahd_send_async(struct ahd_softc *ahd, char channel,
                 starget = ahd->platform_data->starget[target];
                 if (starget == NULL)
                         break;
-                targ = scsi_transport_target_data(starget);
 
                 target_ppr_options =
                         (spi_dt(starget) ? MSG_EXT_PPR_DT_REQ : 0)
@@ -1803,10 +1797,9 @@ ahd_done(struct ahd_softc *ahd, struct scb *scb)
                 if (ahd_get_transaction_status(scb) == CAM_BDR_SENT
                  || ahd_get_transaction_status(scb) == CAM_REQ_ABORTED)
                         ahd_set_transaction_status(scb, CAM_CMD_TIMEOUT);
-                if ((ahd->platform_data->flags & AHD_SCB_UP_EH_SEM) != 0) {
-                        ahd->platform_data->flags &= ~AHD_SCB_UP_EH_SEM;
-                        up(&ahd->platform_data->eh_sem);
-                }
+
+                if (ahd->platform_data->eh_done)
+                        complete(ahd->platform_data->eh_done);
         }
 
         ahd_free_scb(ahd, scb);
@@ -2030,60 +2023,16 @@ ahd_linux_queue_cmd_complete(struct ahd_softc *ahd, struct scsi_cmnd *cmd)
         cmd->scsi_done(cmd);
 }
 
-static void
-ahd_linux_sem_timeout(u_long arg)
-{
-        struct  ahd_softc *ahd;
-        u_long  s;
-
-        ahd = (struct ahd_softc *)arg;
-
-        ahd_lock(ahd, &s);
-        if ((ahd->platform_data->flags & AHD_SCB_UP_EH_SEM) != 0) {
-                ahd->platform_data->flags &= ~AHD_SCB_UP_EH_SEM;
-                up(&ahd->platform_data->eh_sem);
-        }
-        ahd_unlock(ahd, &s);
-}
-
 void
 ahd_freeze_simq(struct ahd_softc *ahd)
 {
-        unsigned long s;
-
-        ahd_lock(ahd, &s);
-        ahd->platform_data->qfrozen++;
-        if (ahd->platform_data->qfrozen == 1) {
-                scsi_block_requests(ahd->platform_data->host);
-                ahd_platform_abort_scbs(ahd, CAM_TARGET_WILDCARD, ALL_CHANNELS,
-                                        CAM_LUN_WILDCARD, SCB_LIST_NULL,
-                                        ROLE_INITIATOR, CAM_REQUEUE_REQ);
-        }
-        ahd_unlock(ahd, &s);
+        scsi_block_requests(ahd->platform_data->host);
 }
 
 void
 ahd_release_simq(struct ahd_softc *ahd)
 {
-        u_long s;
-        int    unblock_reqs;
-
-        unblock_reqs = 0;
-        ahd_lock(ahd, &s);
-        if (ahd->platform_data->qfrozen > 0)
-                ahd->platform_data->qfrozen--;
-        if (ahd->platform_data->qfrozen == 0) {
-                unblock_reqs = 1;
-        }
-        ahd_unlock(ahd, &s);
-        /*
-         * There is still a race here.  The mid-layer
-         * should keep its own freeze count and use
-         * a bottom half handler to run the queues
-         * so we can unblock with our own lock held.
-         */
-        if (unblock_reqs)
-                scsi_unblock_requests(ahd->platform_data->host);
+        scsi_unblock_requests(ahd->platform_data->host);
 }
 
 static int
@@ -2344,30 +2293,29 @@ done:
         if (paused)
                 ahd_unpause(ahd);
         if (wait) {
-                struct timer_list timer;
-                int ret;
+                DECLARE_COMPLETION(done);
 
-                ahd->platform_data->flags |= AHD_SCB_UP_EH_SEM;
+                ahd->platform_data->eh_done = &done;
                 ahd_unlock(ahd, &flags);
 
-                init_timer(&timer);
-                timer.data = (u_long)ahd;
-                timer.expires = jiffies + (5 * HZ);
-                timer.function = ahd_linux_sem_timeout;
-                add_timer(&timer);
                 printf("%s: Recovery code sleeping\n", ahd_name(ahd));
-                down(&ahd->platform_data->eh_sem);
-                printf("%s: Recovery code awake\n", ahd_name(ahd));
-                ret = del_timer_sync(&timer);
-                if (ret == 0) {
+                if (!wait_for_completion_timeout(&done, 5 * HZ)) {
+                        ahd_lock(ahd, &flags);
+                        ahd->platform_data->eh_done = NULL;
+                        ahd_unlock(ahd, &flags);
                         printf("%s: Timer Expired (active %d)\n",
                                ahd_name(ahd), dev->active);
                         retval = FAILED;
                 }
+                printf("Recovery code awake\n");
         } else
                 ahd_unlock(ahd, &flags);
 
-        return (retval);
+        if (retval != SUCCESS)
+                printf("%s: Command abort returning 0x%x\n",
+                       ahd_name(ahd), retval);
+
+        return retval;
 }
 
 static void ahd_linux_set_width(struct scsi_target *starget, int width)
diff --git a/drivers/scsi/aic7xxx/aic79xx_osm.h b/drivers/scsi/aic7xxx/aic79xx_osm.h
index 9cb101345107..599e3940db16 100644
--- a/drivers/scsi/aic7xxx/aic79xx_osm.h
+++ b/drivers/scsi/aic7xxx/aic79xx_osm.h
@@ -381,15 +381,12 @@ struct ahd_platform_data {
         struct scsi_target *starget[AHD_NUM_TARGETS]; 
 
         spinlock_t               spin_lock;
-        u_int                    qfrozen;
-        struct semaphore         eh_sem;
+        struct completion       *eh_done;
         struct Scsi_Host        *host;          /* pointer to scsi host */
 #define AHD_LINUX_NOIRQ ((uint32_t)~0)
         uint32_t                 irq;           /* IRQ for this adapter */
         uint32_t                 bios_address;
         uint32_t                 mem_busaddr;   /* Mem Base Addr */
-#define AHD_SCB_UP_EH_SEM 0x1
-        uint32_t                 flags;
 };
 
 /************************** OS Utility Wrappers *******************************/