[PATCH 5.12 094/292] scsi: storvsc: Correctly handle multiple flags in srb_status

Greg Kroah-Hartman
2021-07-19T18:01:00Z

From: Michael Kelley <mikelley@microsoft.com>

[ Upstream commit 52e1b3b3daa9d53f0204bf474ee1d4b1beb38234 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/scsi/storvsc_drv.c | 61 +++++++++++++++++++++-----------------
1 file changed, 33 insertions(+), 28 deletions(-)

diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index 6bc5453cea8a..181d7b372fd0 100644
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1005,17 +1005,40 @@ 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
@@ -1028,37 +1051,19 @@ 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.
*/
--
2.30.2