From 361f29d46ce4a310818e88adaef0912573847295 Mon Sep 17 00:00:00 2001

From: Cole Robinson <crobinso@redhat.com>

Date: Thu, 14 Jan 2010 16:19:40 +0000

Subject: [PATCH] raw-posix: Detect CDROM via ioctl on linux

Current CDROM detection is hardcoded based on source file name.

Make this smarter on linux by attempting a CDROM specific ioctl.

This makes '-cdrom /dev/sr0' succeed with no media present.

v2:

    Give ioctl check higher priority than filename check.

v3:

    Actually initialize 'prio' variable.

    Check for ioctl success rather than absence of specific failure.

v4:

    Explicitly mention that change is linux specific.

Signed-off-by: Cole Robinson <crobinso@redhat.com>

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

---

 block/raw-posix.c |   20 ++++++++++++++++++--

 1 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/block/raw-posix.c b/block/raw-posix.c

index c204cf9..1c777a1 100644

--- a/block/raw-posix.c

+++ b/block/raw-posix.c

@@ -1142,9 +1142,25 @@ static int cdrom_open(BlockDriverState *bs, const char *filename, int flags)

 static int cdrom_probe_device(const char *filename)

 {

+    int fd, ret;

+    int prio = 0;

+

     if (strstart(filename, "/dev/cd", NULL))

-        return 100;

-    return 0;

+        prio = 50;

+

+    fd = open(filename, O_RDONLY | O_NONBLOCK);

+    if (fd < 0) {

+        goto out;

+    }

+

+    /* Attempt to detect via a CDROM specific ioctl */

+    ret = ioctl(fd, CDROM_DRIVE_STATUS, CDSL_CURRENT);

+    if (ret >= 0)

+        prio = 100;

+

+    close(fd);

+out:

+    return prio;

 }

 static int cdrom_is_inserted(BlockDriverState *bs)

-- 

1.6.6.1