[Qemu-devel] [PATCH 3/4] scsi-disk: fix changeable values returned by the MODE SENSE command

[Bernhard Kohl]

If the page control (PC) field in the MODE SENSE command defines Changeable
Values to be returned in the mode pages, don't return any mode page as there
is no support to change any values.

Signed-off-by: Bernhard Kohl <address@hidden>
---
 hw/scsi-disk.c |    9 ++++++---
 1 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/hw/scsi-disk.c b/hw/scsi-disk.c
index 927df54..26f7345 100644
--- a/hw/scsi-disk.c
+++ b/hw/scsi-disk.c
@@ -604,13 +604,15 @@ static int scsi_disk_emulate_mode_sense(SCSIRequest *req, 
uint8_t *outbuf)
 {
     SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, req->dev);
     uint64_t nb_sectors;
-    int page, dbd, buflen;
+    int page, dbd, buflen, page_control;
     uint8_t *p;
     uint8_t dev_specific_param;
 
     dbd = req->cmd.buf[1]  & 0x8;
     page = req->cmd.buf[2] & 0x3f;
-    DPRINTF("Mode Sense (page %d, len %zd)\n", page, req->cmd.xfer);
+    page_control = (req->cmd.buf[2] & 0xc0) >> 6;
+    DPRINTF("Mode Sense(%d) (page %d, len %d, page_control %d)\n",
+        (req->cmd.buf[0] == MODE_SENSE) ? 6 : 10, page, len, page_control);
     memset(outbuf, 0, req->cmd.xfer);
     p = outbuf;
 
@@ -654,7 +656,8 @@ static int scsi_disk_emulate_mode_sense(SCSIRequest *req, 
uint8_t *outbuf)
         p += 8;
     }
 
-    switch (page) {
+    /* Don't return pages if Changeable Values (1) are requested. */
+    if (page_control != 1) switch (page) {
     case 0x04:
     case 0x05:
     case 0x08:
-- 
1.7.2