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uapi/virtio_scsi: allow overriding CDB/SENSE size

PATCH In review Michael S. Tsirkin 2 participants 5 messages Mar 11, 2015 1 message not in the archive

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Michael S. Tsirkin

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#1 lore raw

PATCH 1/4 virtio-scsi: drop duplicate CDB/SENSE SIZE

This is duplicated from the kernel header,
drop our copy.

Signed-off-by Michael S. Tsirkin <[email protected]>
---
 include/hw/virtio/virtio-scsi.h | 2 --
 1 file changed, 2 deletions(-)
include/hw/virtio/virtio-scsi.h +0 -2
index de2c739..e4b531e 100644
@@ -30,8 +30,6 @@
         OBJECT_CHECK(VirtIOSCSI, (obj), TYPE_VIRTIO_SCSI)
 
 #define VIRTIO_SCSI_VQ_SIZE     128
-#define VIRTIO_SCSI_CDB_SIZE    32
-#define VIRTIO_SCSI_SENSE_SIZE  96
 #define VIRTIO_SCSI_MAX_CHANNEL 0
 #define VIRTIO_SCSI_MAX_TARGET  255
 #define VIRTIO_SCSI_MAX_LUN     16383
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MST
author
#2 lore raw

PATCH 2/4 uapi/virtio_scsi: allow overriding CDB/SENSE size

In reply to a message not in the archive

QEMU wants to use virtio scsi structures with
a different VIRTIO_SCSI_CDB_SIZE/VIRTIO_SCSI_SENSE_SIZE, let's add ifdefs to allow overriding them.

Keep the old defines under new names:
VIRTIO_SCSI_CDB_DEFAULT_SIZE/VIRTIO_SCSI_SENSE_DEFAULT_SIZE, since that's what these values really are:
defaults for cdb/sense size fields.

Suggested-by Paolo Bonzini <[email protected]>
Signed-off-by Michael S. Tsirkin <[email protected]>
---
 include/standard-headers/linux/virtio_scsi.h | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)
include/standard-headers/linux/virtio_scsi.h +10 -2
index 78ba9d3..ab66166 100644
@@ -29,8 +29,16 @@
 
 #include "standard-headers/linux/virtio_types.h"
 
-#define VIRTIO_SCSI_CDB_SIZE   32
-#define VIRTIO_SCSI_SENSE_SIZE 96
+/* Default values of the CDB and sense data size configuration fields */
+#define VIRTIO_SCSI_CDB_DEFAULT_SIZE   32
+#define VIRTIO_SCSI_SENSE_DEFAULT_SIZE 96
+
+#ifndef VIRTIO_SCSI_CDB_SIZE
+#define VIRTIO_SCSI_CDB_SIZE VIRTIO_SCSI_CDB_DEFAULT_SIZE
+#endif
+#ifndef VIRTIO_SCSI_SENSE_SIZE
+#define VIRTIO_SCSI_SENSE_SIZE VIRTIO_SCSI_SENSE_DEFAULT_SIZE
+#endif
 
 /* SCSI command request, followed by data-out */
 struct virtio_scsi_cmd_req {
Signature · 1 line
MST
author
#3 lore raw

PATCH 3/4 virtio-scsi: fix cdb/sense size

In reply to a message not in the archive

Commit "virtio-scsi: use standard-headers" added cdb and sense into req/rep structures, which breaks uses of sizeof for these structures, since qemu adds its own arrays on top.

To fix, redefine CDB/sense field size to 0.

Reported-by Fam Zheng <[email protected]>
Signed-off-by Michael S. Tsirkin <[email protected]>
---
 include/hw/virtio/virtio-scsi.h |  3 +++
 hw/scsi/virtio-scsi.c           | 10 +++++-----
 2 files changed, 8 insertions(+), 5 deletions(-)
include/hw/virtio/virtio-scsi.h +3 -0
index e4b531e..9423865 100644
@@ -14,6 +14,9 @@
 #ifndef _QEMU_VIRTIO_SCSI_H
 #define _QEMU_VIRTIO_SCSI_H
 
+/* Override CDB/sense data size: they are dynamic (guest controlled) in QEMU */
+#define VIRTIO_SCSI_CDB_SIZE 0
+#define VIRTIO_SCSI_SENSE_SIZE 0
 #include "standard-headers/linux/virtio_scsi.h"
 #include "hw/virtio/virtio.h"
 #include "hw/pci/pci.h"
hw/scsi/virtio-scsi.c +5 -5
index cfb52e8..ba51e06 100644
@@ -476,7 +476,7 @@ static int virtio_scsi_parse_cdb(SCSIDevice *dev, SCSICommand *cmd,
     VirtIOSCSIReq *req = hba_private;
 
     if (cmd->len == 0) {
-        cmd->len = MIN(VIRTIO_SCSI_CDB_SIZE, SCSI_CMD_BUF_SIZE);
+        cmd->len = MIN(VIRTIO_SCSI_CDB_DEFAULT_SIZE, SCSI_CMD_BUF_SIZE);
         memcpy(cmd->buf, buf, cmd->len);
     }
 

@@ -642,8 +642,8 @@ static void virtio_scsi_reset(VirtIODevice *vdev)
     qbus_reset_all(&s->bus.qbus);
     s->resetting--;
 
-    vs->sense_size = VIRTIO_SCSI_SENSE_SIZE;
-    vs->cdb_size = VIRTIO_SCSI_CDB_SIZE;
+    vs->sense_size = VIRTIO_SCSI_SENSE_DEFAULT_SIZE;
+    vs->cdb_size = VIRTIO_SCSI_CDB_DEFAULT_SIZE;
     s->events_dropped = false;
 }
 

@@ -830,8 +830,8 @@ void virtio_scsi_common_realize(DeviceState *dev, Error **errp,
         return;
     }
     s->cmd_vqs = g_new0(VirtQueue *, s->conf.num_queues);
-    s->sense_size = VIRTIO_SCSI_SENSE_SIZE;
-    s->cdb_size = VIRTIO_SCSI_CDB_SIZE;
+    s->sense_size = VIRTIO_SCSI_SENSE_DEFAULT_SIZE;
+    s->cdb_size = VIRTIO_SCSI_CDB_DEFAULT_SIZE;
 
     s->ctrl_vq = virtio_add_queue(vdev, VIRTIO_SCSI_VQ_SIZE,
                                   ctrl);
Signature · 1 line
MST
author
#4 lore raw

PATCH 4/4 virtio-scsi: clean out duplicate cdb field

In reply to a message not in the archive

cdb is now part of cmd, drop it from req. There's also nothing to check using build assert now.

Signed-off-by Michael S. Tsirkin <[email protected]>
---
 include/hw/virtio/virtio-scsi.h | 7 +------
 hw/scsi/virtio-scsi.c           | 2 +-
 2 files changed, 2 insertions(+), 7 deletions(-)
include/hw/virtio/virtio-scsi.h +1 -6
index 9423865..e3f27a6 100644
@@ -109,8 +109,7 @@ typedef struct VirtIOSCSIReq {
     /* Note:
      * - fields before elem are initialized by virtio_scsi_init_req;
      * - elem is uninitialized at the time of allocation.
-     * - fields after elem (except the ending cdb[]) are zeroed by
-     *   virtio_scsi_init_req.
+     * - fields after elem are zeroed by virtio_scsi_init_req.
      * */
 
     VirtQueueElement elem;

@@ -137,16 +136,12 @@ typedef struct VirtIOSCSIReq {
     union {
         struct {
             VirtIOSCSICmdReq  cmd;
-            uint8_t           cdb[];
         } QEMU_PACKED;
         VirtIOSCSICtrlTMFReq  tmf;
         VirtIOSCSICtrlANReq   an;
     } req;
 } VirtIOSCSIReq;
 
-QEMU_BUILD_BUG_ON(offsetof(VirtIOSCSIReq, req.cdb) !=
-                  offsetof(VirtIOSCSIReq, req.cmd) + sizeof(VirtIOSCSICmdReq));
-
 #define DEFINE_VIRTIO_SCSI_PROPERTIES(_state, _conf_field)                     \
     DEFINE_PROP_UINT32("num_queues", _state, _conf_field.num_queues, 1),       \
     DEFINE_PROP_UINT32("max_sectors", _state, _conf_field.max_sectors, 0xFFFF),\
hw/scsi/virtio-scsi.c +1 -1
index ba51e06..da0cff8 100644
@@ -544,7 +544,7 @@ bool virtio_scsi_handle_cmd_req_prepare(VirtIOSCSI *s, VirtIOSCSIReq *req)
     }
     req->sreq = scsi_req_new(d, req->req.cmd.tag,
                              virtio_scsi_get_lun(req->req.cmd.lun),
-                             req->req.cdb, req);
+                             req->req.cmd.cdb, req);
 
     if (req->sreq->cmd.mode != SCSI_XFER_NONE
         && (req->sreq->cmd.mode != req->mode ||
Signature · 1 line
MST
Acked-by on v1 4/4
#5 lore raw

Re: [Qemu-devel] [PATCH 4/4] virtio-scsi: clean out duplicate cdb field

Quoted 4 lines · Michael S. Tsirkin
         struct {
             VirtIOSCSICmdReq  cmd;
-            uint8_t           cdb[];
         } QEMU_PACKED;

Just:

    VirtIOSCSICmdReq cmd;

without the wrapping struct.

With this change series

Acked-by Paolo Bonzini <[email protected]>
Quoted 8 lines
         VirtIOSCSICtrlTMFReq  tmf;
         VirtIOSCSICtrlANReq   an;
     } req;

} VirtIOSCSIReq;

include/hw/virtio/virtio-scsi.h +0 -3
-QEMU_BUILD_BUG_ON(offsetof(VirtIOSCSIReq, req.cdb) !=
-                  offsetof(VirtIOSCSIReq, req.cmd) + sizeof(VirtIOSCSICmdReq));
-