[SCSI] storvsc: Restructure error handling code on command completion

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@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

1 files changed, 59 insertions, 42 deletions

diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index 82873e775fc3..95c759fe071a 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);