* [Qemu-devel] [PATCH 1/2] Add a BlockDriverState parameter to bdrv_probe_device()
2009-06-17 20:28 [Qemu-devel] [PATCH 0/2] Guess host device type from guest device type for block devices Eduardo Habkost
@ 2009-06-17 20:28 ` Eduardo Habkost
2009-06-17 20:28 ` [Qemu-devel] [PATCH 2/2] Guess host device type from requested guest device type Eduardo Habkost
2009-06-17 22:17 ` [Qemu-devel] Re: [PATCH 0/2] Guess host device type from guest device type for block devices Anthony Liguori
2 siblings, 0 replies; 4+ messages in thread
From: Eduardo Habkost @ 2009-06-17 20:28 UTC (permalink / raw)
To: Anthony Liguori; +Cc: qemu-devel, Cole Robinson
Some probe functions may behave differently depending on the drive
configuration. For example, if a block device is used as backend for a virtual
cdrom device, the cdrom driver may be used.
Changes not tested on Windows or FreeBSD, but I don't expect them to cause any
problems.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
block.c | 6 +++---
block/raw-posix.c | 8 ++++----
block/raw-win32.c | 2 +-
block_int.h | 2 +-
4 files changed, 9 insertions(+), 9 deletions(-)
diff --git a/block.c b/block.c
index aca5a6d..fa890a7 100644
--- a/block.c
+++ b/block.c
@@ -253,14 +253,14 @@ static BlockDriver *find_protocol(const char *filename)
* Detect host devices. By convention, /dev/cdrom[N] is always
* recognized as a host CDROM.
*/
-static BlockDriver *find_hdev_driver(const char *filename)
+static BlockDriver *find_hdev_driver(BlockDriverState *bs, const char *filename)
{
int score_max = 0, score;
BlockDriver *drv = NULL, *d;
for (d = first_drv; d; d = d->next) {
if (d->bdrv_probe_device) {
- score = d->bdrv_probe_device(filename);
+ score = d->bdrv_probe_device(bs, filename);
if (score > score_max) {
score_max = score;
drv = d;
@@ -397,7 +397,7 @@ int bdrv_open2(BlockDriverState *bs, const char *filename, int flags,
if (flags & BDRV_O_FILE) {
drv = find_protocol(filename);
} else if (!drv) {
- drv = find_hdev_driver(filename);
+ drv = find_hdev_driver(bs, filename);
if (!drv) {
drv = find_image_format(filename);
}
diff --git a/block/raw-posix.c b/block/raw-posix.c
index fa1a394..bbcb6bc 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -955,7 +955,7 @@ kern_return_t GetBSDPath( io_iterator_t mediaIterator, char *bsdPath, CFIndex ma
#endif
-static int hdev_probe_device(const char *filename)
+static int hdev_probe_device(BlockDriverState *bs, const char *filename)
{
struct stat st;
@@ -1201,7 +1201,7 @@ static int floppy_open(BlockDriverState *bs, const char *filename, int flags)
return 0;
}
-static int floppy_probe_device(const char *filename)
+static int floppy_probe_device(BlockDriverState *bs, const char *filename)
{
if (strstart(filename, "/dev/fd", NULL))
return 100;
@@ -1285,7 +1285,7 @@ static int cdrom_open(BlockDriverState *bs, const char *filename, int flags)
return raw_open_common(bs, filename, flags, O_NONBLOCK);
}
-static int cdrom_probe_device(const char *filename)
+static int cdrom_probe_device(BlockDriverState *bs, const char *filename)
{
if (strstart(filename, "/dev/cd", NULL))
return 100;
@@ -1381,7 +1381,7 @@ static int cdrom_open(BlockDriverState *bs, const char *filename, int flags)
return 0;
}
-static int cdrom_probe_device(const char *filename)
+static int cdrom_probe_device(BlockDriverState *bs, const char *filename)
{
if (strstart(filename, "/dev/cd", NULL) ||
strstart(filename, "/dev/acd", NULL))
diff --git a/block/raw-win32.c b/block/raw-win32.c
index 72acad5..7c7e846 100644
--- a/block/raw-win32.c
+++ b/block/raw-win32.c
@@ -306,7 +306,7 @@ static int find_device_type(BlockDriverState *bs, const char *filename)
}
}
-static int hdev_probe_device(const char *filename)
+static int hdev_probe_device(BlockDriverState *bs, const char *filename)
{
if (strstart(filename, "/dev/cdrom", NULL))
return 100;
diff --git a/block_int.h b/block_int.h
index 830b7e9..b70186d 100644
--- a/block_int.h
+++ b/block_int.h
@@ -48,7 +48,7 @@ struct BlockDriver {
const char *format_name;
int instance_size;
int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename);
- int (*bdrv_probe_device)(const char *filename);
+ int (*bdrv_probe_device)(BlockDriverState *bs, const char *filename);
int (*bdrv_open)(BlockDriverState *bs, const char *filename, int flags);
int (*bdrv_read)(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors);
--
1.6.3.rc4.29.g8146
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [Qemu-devel] [PATCH 2/2] Guess host device type from requested guest device type
2009-06-17 20:28 [Qemu-devel] [PATCH 0/2] Guess host device type from guest device type for block devices Eduardo Habkost
2009-06-17 20:28 ` [Qemu-devel] [PATCH 1/2] Add a BlockDriverState parameter to bdrv_probe_device() Eduardo Habkost
@ 2009-06-17 20:28 ` Eduardo Habkost
2009-06-17 22:17 ` [Qemu-devel] Re: [PATCH 0/2] Guess host device type from guest device type for block devices Anthony Liguori
2 siblings, 0 replies; 4+ messages in thread
From: Eduardo Habkost @ 2009-06-17 20:28 UTC (permalink / raw)
To: Anthony Liguori; +Cc: qemu-devel, Cole Robinson
This fixes the following issue:
https://bugzilla.redhat.com/show_bug.cgi?id=473154
Sometimes a CD-ROM drive path doesn't start with /dev/cdrom, causing problems
if a disk isn't inserted on the drive. With this patch, the floppy and cdrom
drivers are used if using a host block device as backend and the
virtual device type is floppy or CD-ROM.
Example:
$ ls -l /dev/cdrom /dev/hda
lrwxrwxrwx 1 root root 3 Jun 17 10:20 /dev/cdrom -> hda
brw-rw---- 1 root disk 3, 0 Jun 17 10:20 /dev/hda
Before this patch (CD-ROM drive with no disk):
$ sudo qemu-system-x86_64 -cdrom /dev/cdrom
[works]
$ sudo qemu-system-x86_64 -cdrom /dev/hda
qemu: could not open disk image /dev/hda
After this patch (with no disk on the CD-ROM drive, too):
$ sudo qemu-system-x86_64 -cdrom /dev/hda
[works]
This is based on a fix from Cole Robinson, submitted here:
http://marc.info/?l=qemu-devel&m=124458617900905
The FreeBSD side of the cdrom driver changes is untested.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
block/raw-posix.c | 30 +++++++++++++++++++++++++-----
1 files changed, 25 insertions(+), 5 deletions(-)
diff --git a/block/raw-posix.c b/block/raw-posix.c
index bbcb6bc..795d465 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -959,13 +959,12 @@ static int hdev_probe_device(BlockDriverState *bs, const char *filename)
{
struct stat st;
- /* allow a dedicated CD-ROM driver to match with a higher priority */
- if (strstart(filename, "/dev/cdrom", NULL))
- return 50;
-
if (stat(filename, &st) >= 0 &&
(S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode))) {
- return 100;
+ /* allow a dedicated driver (e.g. cdrom, floppy) to match with a higher
+ * priority
+ */
+ return 90;
}
return 0;
@@ -1203,8 +1202,15 @@ static int floppy_open(BlockDriverState *bs, const char *filename, int flags)
static int floppy_probe_device(BlockDriverState *bs, const char *filename)
{
+ struct stat st;
+
if (strstart(filename, "/dev/fd", NULL))
return 100;
+
+ if (bs->type == BDRV_TYPE_FLOPPY &&
+ stat(filename, &st) >= 0 && S_ISBLK(st.st_mode))
+ return 100;
+
return 0;
}
@@ -1287,8 +1293,15 @@ static int cdrom_open(BlockDriverState *bs, const char *filename, int flags)
static int cdrom_probe_device(BlockDriverState *bs, const char *filename)
{
+ struct stat st;
+
if (strstart(filename, "/dev/cd", NULL))
return 100;
+
+ if (bs->type == BDRV_TYPE_CDROM &&
+ stat(filename, &st) >= 0 && S_ISBLK(st.st_mode))
+ return 100;
+
return 0;
}
@@ -1383,9 +1396,16 @@ static int cdrom_open(BlockDriverState *bs, const char *filename, int flags)
static int cdrom_probe_device(BlockDriverState *bs, const char *filename)
{
+ struct stat st;
+
if (strstart(filename, "/dev/cd", NULL) ||
strstart(filename, "/dev/acd", NULL))
return 100;
+
+ if (bs->type == BDRV_TYPE_CDROM &&
+ stat(filename, &st) >= 0 && S_ISBLK(st.st_mode))
+ return 100;
+
return 0;
}
--
1.6.3.rc4.29.g8146
^ permalink raw reply related [flat|nested] 4+ messages in thread