block: get rid of the BDRV_O_FILE flag

BDRV_O_FILE is only used to communicate between bdrv_file_open and bdrv_open.
It affects two things:  first bdrv_open only searches for protocols using
find_protocol instead of all image formats and host drivers.  We can easily
move that to the caller and pass the found driver to bdrv_open.  Second
it is used to not force a read-write open of a snapshot file.  But we never
use bdrv_file_open to open snapshots and this behaviour doesn't make sense
to start with.

qemu-io abused the BDRV_O_FILE for it's growable option, switch it to
using bdrv_file_open to make sure we only open files as growable were
we can actually support that.

This patch requires Kevin's "[PATCH] Replace calls of old bdrv_open" to
be applied first.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Christoph Hellwig 2010-04-05 16:53:57 +02:00 committed by Kevin Wolf
parent d6e9098e10
commit 6db956039d
3 changed files with 25 additions and 26 deletions

19
block.c
View File

@ -335,10 +335,16 @@ static BlockDriver *find_image_format(const char *filename)
int bdrv_file_open(BlockDriverState **pbs, const char *filename, int flags)
{
BlockDriverState *bs;
BlockDriver *drv;
int ret;
drv = find_protocol(filename);
if (!drv) {
return -ENOENT;
}
bs = bdrv_new("");
ret = bdrv_open(bs, filename, flags | BDRV_O_FILE, NULL);
ret = bdrv_open(bs, filename, flags, drv);
if (ret < 0) {
bdrv_delete(bs);
return ret;
@ -416,9 +422,8 @@ int bdrv_open(BlockDriverState *bs, const char *filename, int flags,
}
pstrcpy(bs->filename, sizeof(bs->filename), filename);
if (flags & BDRV_O_FILE) {
drv = find_protocol(filename);
} else if (!drv) {
if (!drv) {
drv = find_hdev_driver(filename);
if (!drv) {
drv = find_image_format(filename);
@ -450,14 +455,12 @@ int bdrv_open(BlockDriverState *bs, const char *filename, int flags,
* Clear flags that are internal to the block layer before opening the
* image.
*/
open_flags = flags & ~(BDRV_O_FILE | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING);
open_flags = flags & ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING);
/*
* Snapshots should be writeable.
*
* XXX(hch): and what is the point of a snapshot during a read-only open?
*/
if (!(flags & BDRV_O_FILE) && bs->is_temporary) {
if (bs->is_temporary) {
open_flags |= BDRV_O_RDWR;
}

View File

@ -29,10 +29,6 @@ typedef struct QEMUSnapshotInfo {
#define BDRV_O_RDWR 0x0002
#define BDRV_O_SNAPSHOT 0x0008 /* open the file read only and save writes in a snapshot */
#define BDRV_O_FILE 0x0010 /* open as a raw file (do not try to
use a disk image format on top of
it (default for
bdrv_file_open()) */
#define BDRV_O_NOCACHE 0x0020 /* do not use the host page cache */
#define BDRV_O_CACHE_WB 0x0040 /* use write-back caching */
#define BDRV_O_NATIVE_AIO 0x0080 /* use native AIO instead of the thread pool */

View File

@ -1276,23 +1276,23 @@ static int openfile(char *name, int flags, int growable)
return 1;
}
bs = bdrv_new("hda");
if (!bs)
return 1;
if (growable) {
flags |= BDRV_O_FILE;
if (bdrv_file_open(&bs, name, flags)) {
fprintf(stderr, "%s: can't open device %s\n", progname, name);
return 1;
}
} else {
bs = bdrv_new("hda");
if (!bs)
return 1;
if (bdrv_open(bs, name, flags, NULL) < 0) {
fprintf(stderr, "%s: can't open device %s\n", progname, name);
bs = NULL;
return 1;
}
}
if (bdrv_open(bs, name, flags, NULL) < 0) {
fprintf(stderr, "%s: can't open device %s\n", progname, name);
bs = NULL;
return 1;
}
if (growable) {
bs->growable = 1;
}
return 0;
}