block: Remove second bdrv_open() recursion

This recursion was introduced in commit 505d7583 in order to allow
nesting image formats. It only ever takes effect when the user
explicitly specifies a driver name and that driver isn't suitable for
the protocol level.

We can check this earlier in bdrv_open() and if the explicitly
requested driver is a format driver, clear BDRV_O_PROTOCOL so that
another bs->file layer is opened.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This commit is contained in:
Kevin Wolf 2014-06-04 14:19:44 +02:00
parent b348f3311c
commit 76c591b013

50
block.c
View File

@ -1404,6 +1404,26 @@ int bdrv_open(BlockDriverState **pbs, const char *filename,
goto fail;
}
/* Find the right image format driver */
drv = NULL;
drvname = qdict_get_try_str(options, "driver");
if (drvname) {
drv = bdrv_find_format(drvname);
qdict_del(options, "driver");
if (!drv) {
error_setg(errp, "Unknown driver: '%s'", drvname);
ret = -EINVAL;
goto fail;
}
}
assert(drvname || !(flags & BDRV_O_PROTOCOL));
if (drv && !drv->bdrv_file_open) {
/* If the user explicitly wants a format driver here, we'll need to add
* another layer for the protocol in bs->file */
flags &= ~BDRV_O_PROTOCOL;
}
bs->options = options;
options = qdict_clone_shallow(options);
@ -1426,25 +1446,13 @@ int bdrv_open(BlockDriverState **pbs, const char *filename,
}
}
/* Find the right image format driver */
drv = NULL;
drvname = qdict_get_try_str(options, "driver");
assert(drvname || !(flags & BDRV_O_PROTOCOL));
if (drvname) {
drv = bdrv_find_format(drvname);
qdict_del(options, "driver");
if (!drv) {
error_setg(errp, "Unknown driver: '%s'", drvname);
ret = -EINVAL;
goto fail;
}
} else if (file) {
/* Image format probing */
if (!drv && file) {
ret = find_image_format(file, filename, &drv, &local_err);
if (ret < 0) {
goto fail;
}
} else {
} else if (!drv) {
error_setg(errp, "Must specify either driver or file");
ret = -EINVAL;
goto fail;
@ -1452,16 +1460,8 @@ int bdrv_open(BlockDriverState **pbs, const char *filename,
/* Open the image */
if (flags & BDRV_O_PROTOCOL) {
if (!drv->bdrv_file_open) {
const char *filename;
filename = qdict_get_try_str(options, "filename");
ret = bdrv_open(&bs, filename, NULL, options,
flags & ~BDRV_O_PROTOCOL, drv, &local_err);
options = NULL;
} else {
ret = bdrv_open_common(bs, NULL, options,
flags & ~BDRV_O_PROTOCOL, drv, &local_err);
}
ret = bdrv_open_common(bs, NULL, options,
flags & ~BDRV_O_PROTOCOL, drv, &local_err);
if (!ret) {
bs->growable = 1;
goto done;