hw/scsi: cleanups before VPD BL emulation

To add support for the emulation of Block Limits VPD page
for passthrough devices, a few adjustments in the current code
base is required to avoid repetition and improve clarity.

In scsi-generic.c, detach the Inquiry handling from
scsi_read_complete and put it into a new function called
scsi_handle_inquiry_reply. This change aims to avoid
cluttering of scsi_read_complete when we more logic in the
Inquiry response handling is added in the next patches,
centralizing the changes in the new function.

In scsi-disk.c, take the build of all emulated VPD pages
from scsi_disk_emulate_inquiry and make it available to
other files into a non-static function called
scsi_disk_emulate_vpd_page. Making it public will allow
the future VPD BL emulation code for passthrough devices
to use it from scsi-generic.c, avoiding copy/pasting this
code solely for that purpose. It also has the advantage of
providing emulation of all VPD pages in case we need to
emulate other pages in other scenarios. As a bonus,
scsi_disk_emulate_inquiry got tidier.

Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20180627172432.11120-2-danielhb413@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 38 insertions, 33 deletions

diff --git a/hw/scsi/scsi-generic.c b/hw/scsi/scsi-generic.c
index 03bce8ff39..a04a704bbf 100644
--- a/hw/scsi/scsi-generic.c
+++ b/hw/scsi/scsi-generic.c
@@ -142,6 +142,43 @@ static int execute_command(BlockBackend *blk,
     return 0;
 }
 
+static void scsi_handle_inquiry_reply(SCSIGenericReq *r, SCSIDevice *s)
+{
+    /*
+     *  EVPD set to zero returns the standard INQUIRY data.
+     *
+     *  Check if scsi_version is unset (-1) to avoid re-defining it
+     *  each time an INQUIRY with standard data is received.
+     *  scsi_version is initialized with -1 in scsi_generic_reset
+     *  and scsi_disk_reset, making sure that we'll set the
+     *  scsi_version after a reset. If the version field of the
+     *  INQUIRY response somehow changes after a guest reboot,
+     *  we'll be able to keep track of it.
+     *
+     *  On SCSI-2 and older, first 3 bits of byte 2 is the
+     *  ANSI-approved version, while on later versions the
+     *  whole byte 2 contains the version. Check if we're dealing
+     *  with a newer version and, in that case, assign the
+     *  whole byte.
+     */
+    if (s->scsi_version == -1 && !(r->req.cmd.buf[1] & 0x01)) {
+        s->scsi_version = r->buf[2] & 0x07;
+        if (s->scsi_version > 2) {
+            s->scsi_version = r->buf[2];
+        }
+    }
+    if (s->type == TYPE_DISK && r->req.cmd.buf[2] == 0xb0) {
+        uint32_t max_transfer =
+            blk_get_max_transfer(s->conf.blk) / s->blocksize;
+
+        assert(max_transfer);
+        stl_be_p(&r->buf[8], max_transfer);
+        /* Also take care of the opt xfer len. */
+        stl_be_p(&r->buf[12],
+                 MIN_NON_ZERO(max_transfer, ldl_be_p(&r->buf[12])));
+    }
+}
+
 static void scsi_read_complete(void * opaque, int ret)
 {
     SCSIGenericReq *r = (SCSIGenericReq *)opaque;
@@ -194,39 +231,7 @@ static void scsi_read_complete(void * opaque, int ret)
         }
     }
     if (r->req.cmd.buf[0] == INQUIRY) {
-        /*
-         *  EVPD set to zero returns the standard INQUIRY data.
-         *
-         *  Check if scsi_version is unset (-1) to avoid re-defining it
-         *  each time an INQUIRY with standard data is received.
-         *  scsi_version is initialized with -1 in scsi_generic_reset
-         *  and scsi_disk_reset, making sure that we'll set the
-         *  scsi_version after a reset. If the version field of the
-         *  INQUIRY response somehow changes after a guest reboot,
-         *  we'll be able to keep track of it.
-         *
-         *  On SCSI-2 and older, first 3 bits of byte 2 is the
-         *  ANSI-approved version, while on later versions the
-         *  whole byte 2 contains the version. Check if we're dealing
-         *  with a newer version and, in that case, assign the
-         *  whole byte.
-         */
-        if (s->scsi_version == -1 && !(r->req.cmd.buf[1] & 0x01)) {
-            s->scsi_version = r->buf[2] & 0x07;
-            if (s->scsi_version > 2) {
-                s->scsi_version = r->buf[2];
-            }
-        }
-        if (s->type == TYPE_DISK && r->req.cmd.buf[2] == 0xb0) {
-            uint32_t max_transfer =
-                blk_get_max_transfer(s->conf.blk) / s->blocksize;
-
-            assert(max_transfer);
-            stl_be_p(&r->buf[8], max_transfer);
-            /* Also take care of the opt xfer len. */
-            stl_be_p(&r->buf[12],
-                     MIN_NON_ZERO(max_transfer, ldl_be_p(&r->buf[12])));
-        }
+        scsi_handle_inquiry_reply(r, s);
     }
     scsi_req_data(&r->req, len);
     scsi_req_unref(&r->req);