[PATCH 3/4] Drivers: scsi: storvsc: Restructure error handling code on command completion

From: K. Y. Srinivasan
Date: Thu Feb 21 2013 - 14:37:47 EST


In preparation for handling additional sense codes, restructure and cleanup
the error handling code in the command completion code path.

Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx>
Reviewed-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
---
drivers/scsi/storvsc_drv.c | 101 +++++++++++++++++++++++++------------------
1 files changed, 59 insertions(+), 42 deletions(-)

diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index 2060509..16d5aac 100644
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -761,6 +761,55 @@ cleanup:
return ret;
}

+static void storvsc_handle_error(struct vmscsi_request *vm_srb,
+ struct scsi_cmnd *scmnd,
+ struct Scsi_Host *host,
+ u8 asc, u8 ascq)
+{
+ struct storvsc_scan_work *wrk;
+ void (*process_err_fn)(struct work_struct *work);
+ bool do_work = false;
+
+ switch (vm_srb->srb_status) {
+ case SRB_STATUS_ERROR:
+ /*
+ * If there is an error; offline the device since all
+ * error recovery strategies would have already been
+ * deployed on the host side. However, if the command
+ * were a pass-through command deal with it appropriately.
+ */
+ switch (scmnd->cmnd[0]) {
+ case ATA_16:
+ case ATA_12:
+ set_host_byte(scmnd, DID_PASSTHROUGH);
+ break;
+ default:
+ set_host_byte(scmnd, DID_TARGET_FAILURE);
+ }
+ break;
+ case SRB_STATUS_INVALID_LUN:
+ do_work = true;
+ process_err_fn = storvsc_remove_lun;
+ break;
+ }
+ if (!do_work)
+ return;
+
+ /*
+ * We need to schedule work to process this error; schedule it.
+ */
+ wrk = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
+ if (!wrk) {
+ set_host_byte(scmnd, DID_TARGET_FAILURE);
+ return;
+ }
+
+ wrk->host = host;
+ wrk->lun = vm_srb->lun;
+ INIT_WORK(&wrk->work, process_err_fn);
+ schedule_work(&wrk->work);
+}
+

static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request)
{
@@ -769,8 +818,13 @@ static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request)
void (*scsi_done_fn)(struct scsi_cmnd *);
struct scsi_sense_hdr sense_hdr;
struct vmscsi_request *vm_srb;
- struct storvsc_scan_work *wrk;
struct stor_mem_pools *memp = scmnd->device->hostdata;
+ struct Scsi_Host *host;
+ struct storvsc_device *stor_dev;
+ struct hv_device *dev = host_dev->dev;
+
+ stor_dev = get_in_stor_device(dev);
+ host = stor_dev->host;

vm_srb = &cmd_request->vstor_packet.vm_srb;
if (cmd_request->bounce_sgl_count) {
@@ -783,55 +837,18 @@ static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request)
cmd_request->bounce_sgl_count);
}

- /*
- * If there is an error; offline the device since all
- * error recovery strategies would have already been
- * deployed on the host side. However, if the command
- * were a pass-through command deal with it appropriately.
- */
scmnd->result = vm_srb->scsi_status;

- if (vm_srb->srb_status == SRB_STATUS_ERROR) {
- switch (scmnd->cmnd[0]) {
- case ATA_16:
- case ATA_12:
- set_host_byte(scmnd, DID_PASSTHROUGH);
- break;
- default:
- set_host_byte(scmnd, DID_TARGET_FAILURE);
- }
- }
-
-
- /*
- * If the LUN is invalid; remove the device.
- */
- if (vm_srb->srb_status == SRB_STATUS_INVALID_LUN) {
- struct storvsc_device *stor_dev;
- struct hv_device *dev = host_dev->dev;
- struct Scsi_Host *host;
-
- stor_dev = get_in_stor_device(dev);
- host = stor_dev->host;
-
- wrk = kmalloc(sizeof(struct storvsc_scan_work),
- GFP_ATOMIC);
- if (!wrk) {
- scmnd->result = DID_TARGET_FAILURE << 16;
- } else {
- wrk->host = host;
- wrk->lun = vm_srb->lun;
- INIT_WORK(&wrk->work, storvsc_remove_lun);
- schedule_work(&wrk->work);
- }
- }
-
if (scmnd->result) {
if (scsi_normalize_sense(scmnd->sense_buffer,
SCSI_SENSE_BUFFERSIZE, &sense_hdr))
scsi_print_sense_hdr("storvsc", &sense_hdr);
}

+ if (vm_srb->srb_status != SRB_STATUS_SUCCESS)
+ storvsc_handle_error(vm_srb, scmnd, host, sense_hdr.asc,
+ sense_hdr.ascq);
+
scsi_set_resid(scmnd,
cmd_request->data_buffer.len -
vm_srb->data_transfer_length);
--
1.7.4.1

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