diff options
| -rw-r--r-- | block.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/block.c b/block.c index 35a372df57..d9ac0e07eb 100644 --- a/block.c +++ b/block.c @@ -2025,6 +2025,22 @@ static int bdrv_check_perm(BlockDriverState *bs, BlockReopenQueue *q, return -EPERM; } + /* + * Unaligned requests will automatically be aligned to bl.request_alignment + * and without RESIZE we can't extend requests to write to space beyond the + * end of the image, so it's required that the image size is aligned. + */ + if ((cumulative_perms & (BLK_PERM_WRITE | BLK_PERM_WRITE_UNCHANGED)) && + !(cumulative_perms & BLK_PERM_RESIZE)) + { + if ((bs->total_sectors * BDRV_SECTOR_SIZE) % bs->bl.request_alignment) { + error_setg(errp, "Cannot get 'write' permission without 'resize': " + "Image size is not a multiple of request " + "alignment"); + return -EPERM; + } + } + /* Check this node */ if (!drv) { return 0; |