hpsa: prevent concurrent rescans

Prevent driver initiated and externally initiated
rescans from occurring simultaneously.

Signed-off-by: Don Brace <don.brace@microsemi.com>
Orabug: 25605941
Signed-off-by: Jack Vogel <jack.vogel@oracle.com>

diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index 1c6b8cc8612f4287ba4b0573a08128a774f9c839..24fa51399a0927b2c82629cba7ab13d73160350b 100644 (file)
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -5598,11 +5598,24 @@ static void hpsa_scan_start(struct Scsi_Host *sh)
        if (unlikely(lockup_detected(h)))
                return hpsa_scan_complete(h);
 
+       /*
+        * If a scan is alreay waiting to run, no need to add another
+        */
+       spin_lock_irqsave(&h->scan_lock, flags);
+       if (h->scan_waiting) {
+               wake_up_all(&h->scan_wait_queue);
+               spin_unlock_irqrestore(&h->scan_lock, flags);
+               return;
+       }
+
+       spin_unlock_irqrestore(&h->scan_lock, flags);
+
        /* wait until any scan already in progress is finished. */
        while (1) {
                spin_lock_irqsave(&h->scan_lock, flags);
                if (h->scan_finished)
                        break;
+               h->scan_waiting = 1;
                spin_unlock_irqrestore(&h->scan_lock, flags);
                wait_event(h->scan_wait_queue, h->scan_finished);
                /* Note: We don't need to worry about a race between this
@@ -5612,6 +5625,7 @@ static void hpsa_scan_start(struct Scsi_Host *sh)
                 */
        }
        h->scan_finished = 0; /* mark scan as in progress */
+       h->scan_waiting = 0;
        spin_unlock_irqrestore(&h->scan_lock, flags);
 
        if (unlikely(lockup_detected(h)))
@@ -8707,6 +8721,11 @@ static void hpsa_rescan_ctlr_worker(struct work_struct *work)
                return;
        }
 
+       if (h->scan_waiting) {
+               h->drv_req_rescan = 1;
+               return;
+       }
+
        if (hpsa_ctlr_needs_rescan(h) || hpsa_offline_devices_ready(h)) {
                scsi_host_get(h->scsi_host);
                hpsa_ack_ctlr_events(h);
@@ -8869,6 +8888,7 @@ reinit_after_soft_reset:
        init_waitqueue_head(&h->event_sync_wait_queue);
        mutex_init(&h->reset_mutex);
        h->scan_finished = 1; /* no scan currently in progress */
+       h->scan_waiting = 0;
 
        pci_set_drvdata(pdev, h);
        h->ndevices = 0;

diff --git a/drivers/scsi/hpsa.h b/drivers/scsi/hpsa.h
index 1858fa2b129ecda137e889b718c57660deb252de..2a7794903d19fec794213933930fcb48d9226c0d 100644 (file)
--- a/drivers/scsi/hpsa.h
+++ b/drivers/scsi/hpsa.h
@@ -204,6 +204,7 @@ struct ctlr_info {
        dma_addr_t              errinfo_pool_dhandle;
        unsigned long           *cmd_pool_bits;
        int                     scan_finished;
+       u8                      scan_waiting : 1;
        spinlock_t              scan_lock;
        wait_queue_head_t       scan_wait_queue;