We can figure out the necessary permissions from the flags that the caller passed.
Signed-off-by: Kevin Wolf <kw...@redhat.com> --- block/block-backend.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/block/block-backend.c b/block/block-backend.c index 1f80854..e10a278 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -160,6 +160,7 @@ BlockBackend *blk_new_open(const char *filename, const char *reference, { BlockBackend *blk; BlockDriverState *bs; + uint64_t perm; blk = blk_new(0, BLK_PERM_ALL); bs = bdrv_open(filename, reference, options, flags, errp); @@ -168,9 +169,20 @@ BlockBackend *blk_new_open(const char *filename, const char *reference, return NULL; } - /* FIXME Use real permissions */ + /* blk_new_open() is mainly used in .bdrv_create implementations and the + * tools where sharing isn't a concern because the BDS stays private, so we + * just request permission according to the flags. + * + * The exceptions are xen_disk and blockdev_init(); in these cases, the + * caller of blk_new_open() doesn't make use of the permissions, but they + * shouldn't hurt either. We can still share everything here because the + * guest devices will add their own blockers if they can't share. */ + perm = BLK_PERM_CONSISTENT_READ; + if (flags & BDRV_O_RDWR) { + perm |= BLK_PERM_WRITE; + } blk->root = bdrv_root_attach_child(bs, "root", &child_root, - 0, BLK_PERM_ALL, blk, &error_abort); + perm, BLK_PERM_ALL, blk, &error_abort); return blk; } -- 1.8.3.1