[Qemu-devel] [PATCH 06/10] scsi: pass residual amount to command_complete

[Paolo Bonzini <pbonzini@redhat.com>]

With the upcoming sglist support, HBAs will not see any transfer_data
call and will not have a way to detect short transfers.  So pass the
residual amount of data upon command completion.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 hw/esp.c         |    3 ++-
 hw/lsi53c895a.c  |    2 +-
 hw/scsi-bus.c    |    6 +++++-
 hw/scsi.h        |    3 ++-
 hw/spapr_vscsi.c |    2 +-
 hw/usb-msd.c     |    2 +-
 6 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/hw/esp.c b/hw/esp.c
index be3a35d..5d29071 100644
--- a/hw/esp.c
+++ b/hw/esp.c
@@ -395,7 +395,8 @@ static void esp_do_dma(ESPState *s)
     esp_dma_done(s);
 }
 
-static void esp_command_complete(SCSIRequest *req, uint32_t status)
+static void esp_command_complete(SCSIRequest *req, uint32_t status,
+                                 int32_t resid)
 {
     ESPState *s = DO_UPCAST(ESPState, busdev.qdev, req->bus->qbus.parent);
 
diff --git a/hw/lsi53c895a.c b/hw/lsi53c895a.c
index dac176a..a0c2419 100644
--- a/hw/lsi53c895a.c
+++ b/hw/lsi53c895a.c
@@ -706,7 +706,7 @@ static int lsi_queue_req(LSIState *s, SCSIRequest *req, uint32_t len)
 }
 
  /* Callback to indicate that the SCSI layer has completed a command.  */
-static void lsi_command_complete(SCSIRequest *req, uint32_t status)
+static void lsi_command_complete(SCSIRequest *req, uint32_t status, int32_t resid)
 {
     LSIState *s = DO_UPCAST(LSIState, dev.qdev, req->bus->qbus.parent);
     int out;
diff --git a/hw/scsi-bus.c b/hw/scsi-bus.c
index 648b1f9..b49d02d 100644
--- a/hw/scsi-bus.c
+++ b/hw/scsi-bus.c
@@ -394,6 +394,8 @@ SCSIRequest *scsi_req_new(SCSIDevice *d, uint32_t tag, uint32_t lun,
     }
 
     req->cmd = cmd;
+    req->resid = req->cmd.xfer;
+
     switch (buf[0]) {
     case INQUIRY:
         trace_scsi_inquiry(d->id, lun, tag, cmd.buf[1], cmd.buf[2]);
@@ -1043,6 +1045,8 @@ void scsi_req_continue(SCSIRequest *req)
 void scsi_req_data(SCSIRequest *req, int len)
 {
     trace_scsi_req_data(req->dev->id, req->lun, req->tag, len);
+    assert(req->cmd.mode != SCSI_XFER_NONE);
+    req->resid -= len;
     req->bus->ops->transfer_data(req, len);
 }
 
@@ -1091,7 +1095,7 @@ void scsi_req_complete(SCSIRequest *req, int status)
 
     scsi_req_ref(req);
     scsi_req_dequeue(req);
-    req->bus->ops->complete(req, req->status);
+    req->bus->ops->complete(req, req->status, req->resid);
     scsi_req_unref(req);
 }
 
diff --git a/hw/scsi.h b/hw/scsi.h
index 98fd689..76d4df2 100644
--- a/hw/scsi.h
+++ b/hw/scsi.h
@@ -47,6 +47,7 @@ struct SCSIRequest {
     uint32_t          tag;
     uint32_t          lun;
     uint32_t          status;
+    size_t            resid;
     SCSICommand       cmd;
     BlockDriverAIOCB  *aiocb;
     uint8_t sense[SCSI_SENSE_BUF_SIZE];
@@ -98,7 +99,7 @@ struct SCSIDeviceInfo {
 
 struct SCSIBusOps {
     void (*transfer_data)(SCSIRequest *req, uint32_t arg);
-    void (*complete)(SCSIRequest *req, uint32_t arg);
+    void (*complete)(SCSIRequest *req, uint32_t arg, int32_t len);
     void (*cancel)(SCSIRequest *req);
 };
 
diff --git a/hw/spapr_vscsi.c b/hw/spapr_vscsi.c
index 1f4de11..128b5a6 100644
--- a/hw/spapr_vscsi.c
+++ b/hw/spapr_vscsi.c
@@ -467,7 +467,7 @@ static void vscsi_transfer_data(SCSIRequest *sreq, uint32_t len)
 }
 
 /* Callback to indicate that the SCSI layer has completed a transfer.  */
-static void vscsi_command_complete(SCSIRequest *sreq, uint32_t status)
+static void vscsi_command_complete(SCSIRequest *sreq, uint32_t status, int32_t resid)
 {
     VSCSIState *s = DO_UPCAST(VSCSIState, vdev.qdev, sreq->bus->qbus.parent);
     vscsi_req *req = sreq->hba_private;
diff --git a/hw/usb-msd.c b/hw/usb-msd.c
index 63305b8..8cddf80 100644
--- a/hw/usb-msd.c
+++ b/hw/usb-msd.c
@@ -232,7 +232,7 @@ static void usb_msd_transfer_data(SCSIRequest *req, uint32_t len)
     }
 }
 
-static void usb_msd_command_complete(SCSIRequest *req, uint32_t status)
+static void usb_msd_command_complete(SCSIRequest *req, uint32_t status, int32_t resid)
 {
     MSDState *s = DO_UPCAST(MSDState, dev.qdev, req->bus->qbus.parent);
     USBPacket *p = s->packet;
-- 
1.7.6