diff options
Diffstat (limited to 'block.c')
-rw-r--r-- | block.c | 19 |
1 files changed, 15 insertions, 4 deletions
@@ -331,11 +331,10 @@ int bdrv_open(BlockDriverState *bs, const char *filename, int flags) int bdrv_open2(BlockDriverState *bs, const char *filename, int flags, BlockDriver *drv) { - int ret, open_flags; + int ret, open_flags, try_rw; char tmp_filename[PATH_MAX]; char backing_filename[PATH_MAX]; - bs->read_only = 0; bs->is_temporary = 0; bs->encrypted = 0; bs->valid_key = 0; @@ -422,9 +421,10 @@ int bdrv_open2(BlockDriverState *bs, const char *filename, int flags, /* Note: for compatibility, we open disk image files as RDWR, and RDONLY as fallback */ + try_rw = !bs->read_only || bs->is_temporary; if (!(flags & BDRV_O_FILE)) - open_flags = BDRV_O_RDWR | - (flags & (BDRV_O_CACHE_MASK|BDRV_O_NATIVE_AIO)); + open_flags = (try_rw ? BDRV_O_RDWR : 0) | + (flags & (BDRV_O_CACHE_MASK|BDRV_O_NATIVE_AIO)); else open_flags = flags & ~(BDRV_O_FILE | BDRV_O_SNAPSHOT); ret = drv->bdrv_open(bs, filename, open_flags); @@ -453,6 +453,8 @@ int bdrv_open2(BlockDriverState *bs, const char *filename, int flags, /* if there is a backing file, use it */ BlockDriver *back_drv = NULL; bs->backing_hd = bdrv_new(""); + /* pass on read_only property to the backing_hd */ + bs->backing_hd->read_only = bs->read_only; path_combine(backing_filename, sizeof(backing_filename), filename, bs->backing_file); if (bs->backing_format[0] != '\0') @@ -731,6 +733,8 @@ int bdrv_truncate(BlockDriverState *bs, int64_t offset) return -ENOMEDIUM; if (!drv->bdrv_truncate) return -ENOTSUP; + if (bs->read_only) + return -EACCES; return drv->bdrv_truncate(bs, offset); } @@ -925,6 +929,13 @@ int bdrv_is_read_only(BlockDriverState *bs) return bs->read_only; } +int bdrv_set_read_only(BlockDriverState *bs, int read_only) +{ + int ret = bs->read_only; + bs->read_only = read_only; + return ret; +} + int bdrv_is_sg(BlockDriverState *bs) { return bs->sg; |