diff options
Diffstat (limited to 'block.c')
| -rw-r--r-- | block.c | 32 |
1 files changed, 20 insertions, 12 deletions
@@ -684,6 +684,10 @@ static void bdrv_temp_snapshot_options(int *child_flags, QDict *child_options, /* For temporary files, unconditional cache=unsafe is fine */ qdict_set_default_str(child_options, BDRV_OPT_CACHE_DIRECT, "off"); qdict_set_default_str(child_options, BDRV_OPT_CACHE_NO_FLUSH, "on"); + + /* aio=native doesn't work for cache.direct=off, so disable it for the + * temporary snapshot */ + *child_flags &= ~BDRV_O_NATIVE_AIO; } /* @@ -937,8 +941,7 @@ static int bdrv_open_common(BlockDriverState *bs, BdrvChild *file, goto fail_opts; } - bs->request_alignment = 512; - bs->zero_beyond_eof = true; + bs->request_alignment = drv->bdrv_co_preadv ? 1 : 512; bs->read_only = !(bs->open_flags & BDRV_O_RDWR); if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, bs->read_only)) { @@ -2192,7 +2195,6 @@ static void bdrv_close(BlockDriverState *bs) bs->encrypted = 0; bs->valid_key = 0; bs->sg = 0; - bs->zero_beyond_eof = false; QDECREF(bs->options); QDECREF(bs->explicit_options); bs->options = NULL; @@ -2224,9 +2226,23 @@ void bdrv_close_all(void) static void change_parent_backing_link(BlockDriverState *from, BlockDriverState *to) { - BdrvChild *c, *next; + BdrvChild *c, *next, *to_c; QLIST_FOREACH_SAFE(c, &from->parents, next_parent, next) { + if (c->role == &child_backing) { + /* @from is generally not allowed to be a backing file, except for + * when @to is the overlay. In that case, @from may not be replaced + * by @to as @to's backing node. */ + QLIST_FOREACH(to_c, &to->children, next) { + if (to_c == c) { + break; + } + } + if (to_c) { + continue; + } + } + assert(c->role != &child_backing); bdrv_ref(to); bdrv_replace_child(c, to); @@ -2275,14 +2291,6 @@ void bdrv_replace_in_backing_chain(BlockDriverState *old, BlockDriverState *new) change_parent_backing_link(old, new); - /* Change backing files if a previously independent node is added to the - * chain. For active commit, we replace top by its own (indirect) backing - * file and don't do anything here so we don't build a loop. */ - if (new->backing == NULL && !bdrv_chain_contains(backing_bs(old), new)) { - bdrv_set_backing_hd(new, backing_bs(old)); - bdrv_set_backing_hd(old, NULL); - } - bdrv_unref(old); } |