scsi: storvsc: Correctly handle multiple flags in srb_status

Hyper-V is observed to sometimes set multiple flags in the srb_status, such
as ABORTED and ERROR. Current code in storvsc_handle_error() handles only a
single flag being set, and does nothing when multiple flags are set.  Fix
this by changing the case statement into a series of "if" statements
testing individual flags. The functionality for handling each flag is
unchanged.

Link: https://lore.kernel.org/r/1622827263-12516-3-git-send-email-mikelley@microsoft.com
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index b4ea671..8488ca1 100644 (file)
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1009,17 +1009,40 @@ static void storvsc_handle_error(struct vmscsi_request *vm_srb,
        struct storvsc_scan_work *wrk;
        void (*process_err_fn)(struct work_struct *work);
        struct hv_host_device *host_dev = shost_priv(host);
-       bool do_work = false;
 
-       switch (SRB_STATUS(vm_srb->srb_status)) {
-       case SRB_STATUS_ERROR:
+       /*
+        * In some situations, Hyper-V sets multiple bits in the
+        * srb_status, such as ABORTED and ERROR. So process them
+        * individually, with the most specific bits first.
+        */
+
+       if (vm_srb->srb_status & SRB_STATUS_INVALID_LUN) {
+               set_host_byte(scmnd, DID_NO_CONNECT);
+               process_err_fn = storvsc_remove_lun;
+               goto do_work;
+       }
+
+       if (vm_srb->srb_status & SRB_STATUS_ABORTED) {
+               if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID &&
+                   /* Capacity data has changed */
+                   (asc == 0x2a) && (ascq == 0x9)) {
+                       process_err_fn = storvsc_device_scan;
+                       /*
+                        * Retry the I/O that triggered this.
+                        */
+                       set_host_byte(scmnd, DID_REQUEUE);
+                       goto do_work;
+               }
+       }
+
+       if (vm_srb->srb_status & SRB_STATUS_ERROR) {
                /*
                 * Let upper layer deal with error when
                 * sense message is present.
                 */
-
                if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID)
-                       break;
+                       return;
+
                /*
                 * If there is an error; offline the device since all
                 * error recovery strategies would have already been
@@ -1032,37 +1055,19 @@ static void storvsc_handle_error(struct vmscsi_request *vm_srb,
                        set_host_byte(scmnd, DID_PASSTHROUGH);
                        break;
                /*
-                * On Some Windows hosts TEST_UNIT_READY command can return
-                * SRB_STATUS_ERROR, let the upper level code deal with it
-                * based on the sense information.
+                * On some Hyper-V hosts TEST_UNIT_READY command can
+                * return SRB_STATUS_ERROR. Let the upper level code
+                * deal with it based on the sense information.
                 */
                case TEST_UNIT_READY:
                        break;
                default:
                        set_host_byte(scmnd, DID_ERROR);
                }
-               break;
-       case SRB_STATUS_INVALID_LUN:
-               set_host_byte(scmnd, DID_NO_CONNECT);
-               do_work = true;
-               process_err_fn = storvsc_remove_lun;
-               break;
-       case SRB_STATUS_ABORTED:
-               if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID &&
-                   (asc == 0x2a) && (ascq == 0x9)) {
-                       do_work = true;
-                       process_err_fn = storvsc_device_scan;
-                       /*
-                        * Retry the I/O that triggered this.
-                        */
-                       set_host_byte(scmnd, DID_REQUEUE);
-               }
-               break;
        }
+       return;
 
-       if (!do_work)
-               return;
-
+do_work:
        /*
         * We need to schedule work to process this error; schedule it.
         */