[Qemu-devel] [PATCH 02/16] vscsi: always use get_sense

[Paolo Bonzini]

vscsi supports autosensing by providing sense data directly in the
response.  When get_sense was added, the older state machine approach
that sent REQUEST SENSE commands separately was left in place.  Remove
it, all existing SCSIDevices do support autosensing and the next patches
will make the support come for free from the SCSIBus.

Signed-off-by: Paolo Bonzini <address@hidden>
---
 hw/spapr_vscsi.c |   91 ++++++++++++-----------------------------------------
 1 files changed, 21 insertions(+), 70 deletions(-)

diff --git a/hw/spapr_vscsi.c b/hw/spapr_vscsi.c
index 646b1e3..c65308c 100644
--- a/hw/spapr_vscsi.c
+++ b/hw/spapr_vscsi.c
@@ -80,7 +80,6 @@ typedef struct vscsi_req {
     int                     active;
     long                    data_len;
     int                     writing;
-    int                     sensing;
     int                     senselen;
     uint8_t                 sense[SCSI_SENSE_BUF_SIZE];
 
@@ -436,40 +435,6 @@ static int vscsi_preprocess_desc(vscsi_req *req)
     return 0;
 }
 
-static void vscsi_send_request_sense(VSCSIState *s, vscsi_req *req)
-{
-    uint8_t *cdb = req->iu.srp.cmd.cdb;
-    int n;
-
-    n = scsi_req_get_sense(req->sreq, req->sense, sizeof(req->sense));
-    if (n) {
-        req->senselen = n;
-        vscsi_send_rsp(s, req, CHECK_CONDITION, 0, 0);
-        vscsi_put_req(req);
-        return;
-    }
-
-    dprintf("VSCSI: Got CHECK_CONDITION, requesting sense...\n");
-    cdb[0] = 3;
-    cdb[1] = 0;
-    cdb[2] = 0;
-    cdb[3] = 0;
-    cdb[4] = 96;
-    cdb[5] = 0;
-    req->sensing = 1;
-    n = scsi_req_enqueue(req->sreq, cdb);
-    dprintf("VSCSI: Queued request sense tag 0x%x\n", req->qtag);
-    if (n < 0) {
-        fprintf(stderr, "VSCSI: REQUEST_SENSE wants write data !?!?!?\n");
-        vscsi_makeup_sense(s, req, HARDWARE_ERROR, 0, 0);
-        scsi_req_abort(req->sreq, CHECK_CONDITION);
-        return;
-    } else if (n == 0) {
-        return;
-    }
-    scsi_req_continue(req->sreq);
-}
-
 /* Callback to indicate that the SCSI layer has completed a transfer.  */
 static void vscsi_transfer_data(SCSIRequest *sreq, uint32_t len)
 {
@@ -485,23 +450,6 @@ static void vscsi_transfer_data(SCSIRequest *sreq, 
uint32_t len)
         return;
     }
 
-    if (req->sensing) {
-        uint8_t *buf = scsi_req_get_buf(sreq);
-
-        len = MIN(len, SCSI_SENSE_BUF_SIZE);
-        dprintf("VSCSI: Sense data, %d bytes:\n", len);
-        dprintf("       %02x  %02x  %02x  %02x  %02x  %02x  %02x  %02x\n",
-                buf[0], buf[1], buf[2], buf[3],
-                buf[4], buf[5], buf[6], buf[7]);
-        dprintf("       %02x  %02x  %02x  %02x  %02x  %02x  %02x  %02x\n",
-                buf[8], buf[9], buf[10], buf[11],
-                buf[12], buf[13], buf[14], buf[15]);
-        memcpy(req->sense, buf, len);
-        req->senselen = len;
-        scsi_req_continue(req->sreq);
-        return;
-    }
-
     if (len) {
         buf = scsi_req_get_buf(sreq);
         rc = vscsi_srp_transfer_data(s, req, req->writing, buf, len);
@@ -532,28 +480,31 @@ static void vscsi_command_complete(SCSIRequest *sreq, 
uint32_t status)
         return;
     }
 
-    if (!req->sensing && status == CHECK_CONDITION) {
-        vscsi_send_request_sense(s, req);
-        return;
+    if (status == CHECK_CONDITION) {
+        req->senselen = scsi_req_get_sense(req->sreq, req->sense,
+                                           sizeof(req->sense));
+        status = 0;
+        dprintf("VSCSI: Sense data, %d bytes:\n", len);
+        dprintf("       %02x  %02x  %02x  %02x  %02x  %02x  %02x  %02x\n",
+                req->sense[0], req->sense[1], req->sense[2], req->sense[3],
+                req->sense[4], req->sense[5], req->sense[6], req->sense[7]);
+        dprintf("       %02x  %02x  %02x  %02x  %02x  %02x  %02x  %02x\n",
+                req->sense[8], req->sense[9], req->sense[10], req->sense[11],
+                req->sense[12], req->sense[13], req->sense[14], 
req->sense[15]);
     }
 
-    if (req->sensing) {
-        dprintf("VSCSI: Sense done !\n");
-        status = CHECK_CONDITION;
-    } else {
-        dprintf("VSCSI: Command complete err=%d\n", status);
-        if (status == 0) {
-            /* We handle overflows, not underflows for normal commands,
-             * but hopefully nobody cares
-             */
-            if (req->writing) {
-                res_out = req->data_len;
-            } else {
-                res_in = req->data_len;
-            }
+    dprintf("VSCSI: Command complete err=%d\n", status);
+    if (status == 0) {
+        /* We handle overflows, not underflows for normal commands,
+         * but hopefully nobody cares
+         */
+        if (req->writing) {
+            res_out = req->data_len;
+        } else {
+            res_in = req->data_len;
         }
     }
-    vscsi_send_rsp(s, req, 0, res_in, res_out);
+    vscsi_send_rsp(s, req, status, res_in, res_out);
     vscsi_put_req(req);
 }
 
-- 
1.7.6