aboutsummaryrefslogtreecommitdiff
path: root/block.c
diff options
context:
space:
mode:
Diffstat (limited to 'block.c')
-rw-r--r--block.c89
1 files changed, 71 insertions, 18 deletions
diff --git a/block.c b/block.c
index 9a1a0d1e73..a8da4f2b25 100644
--- a/block.c
+++ b/block.c
@@ -822,6 +822,18 @@ static void bdrv_child_cb_drained_end(BdrvChild *child)
bdrv_drained_end(bs);
}
+static void bdrv_child_cb_attach(BdrvChild *child)
+{
+ BlockDriverState *bs = child->opaque;
+ bdrv_apply_subtree_drain(child, bs);
+}
+
+static void bdrv_child_cb_detach(BdrvChild *child)
+{
+ BlockDriverState *bs = child->opaque;
+ bdrv_unapply_subtree_drain(child, bs);
+}
+
static int bdrv_child_cb_inactivate(BdrvChild *child)
{
BlockDriverState *bs = child->opaque;
@@ -889,6 +901,8 @@ const BdrvChildRole child_file = {
.inherit_options = bdrv_inherited_options,
.drained_begin = bdrv_child_cb_drained_begin,
.drained_end = bdrv_child_cb_drained_end,
+ .attach = bdrv_child_cb_attach,
+ .detach = bdrv_child_cb_detach,
.inactivate = bdrv_child_cb_inactivate,
};
@@ -911,6 +925,8 @@ const BdrvChildRole child_format = {
.inherit_options = bdrv_inherited_fmt_options,
.drained_begin = bdrv_child_cb_drained_begin,
.drained_end = bdrv_child_cb_drained_end,
+ .attach = bdrv_child_cb_attach,
+ .detach = bdrv_child_cb_detach,
.inactivate = bdrv_child_cb_inactivate,
};
@@ -953,6 +969,8 @@ static void bdrv_backing_attach(BdrvChild *c)
parent->backing_blocker);
bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_BACKUP_TARGET,
parent->backing_blocker);
+
+ bdrv_child_cb_attach(c);
}
static void bdrv_backing_detach(BdrvChild *c)
@@ -963,6 +981,8 @@ static void bdrv_backing_detach(BdrvChild *c)
bdrv_op_unblock_all(c->bs, parent->backing_blocker);
error_free(parent->backing_blocker);
parent->backing_blocker = NULL;
+
+ bdrv_child_cb_detach(c);
}
/*
@@ -1924,6 +1944,8 @@ void bdrv_format_default_perms(BlockDriverState *bs, BdrvChild *c,
assert(role == &child_backing || role == &child_file);
if (!backing) {
+ int flags = bdrv_reopen_get_flags(reopen_queue, bs);
+
/* Apart from the modifications below, the same permissions are
* forwarded and left alone as for filters */
bdrv_filter_default_perms(bs, c, role, reopen_queue, perm, shared,
@@ -1936,7 +1958,9 @@ void bdrv_format_default_perms(BlockDriverState *bs, BdrvChild *c,
/* bs->file always needs to be consistent because of the metadata. We
* can never allow other users to resize or write to it. */
- perm |= BLK_PERM_CONSISTENT_READ;
+ if (!(flags & BDRV_O_NO_IO)) {
+ perm |= BLK_PERM_CONSISTENT_READ;
+ }
shared &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE);
} else {
/* We want consistent read from backing files if the parent needs it.
@@ -1968,17 +1992,23 @@ static void bdrv_replace_child_noperm(BdrvChild *child,
BlockDriverState *new_bs)
{
BlockDriverState *old_bs = child->bs;
+ int i;
if (old_bs && new_bs) {
assert(bdrv_get_aio_context(old_bs) == bdrv_get_aio_context(new_bs));
}
if (old_bs) {
- if (old_bs->quiesce_counter && child->role->drained_end) {
- child->role->drained_end(child);
- }
+ /* Detach first so that the recursive drain sections coming from @child
+ * are already gone and we only end the drain sections that came from
+ * elsewhere. */
if (child->role->detach) {
child->role->detach(child);
}
+ if (old_bs->quiesce_counter && child->role->drained_end) {
+ for (i = 0; i < old_bs->quiesce_counter; i++) {
+ child->role->drained_end(child);
+ }
+ }
QLIST_REMOVE(child, next_parent);
}
@@ -1987,9 +2017,14 @@ static void bdrv_replace_child_noperm(BdrvChild *child,
if (new_bs) {
QLIST_INSERT_HEAD(&new_bs->parents, child, next_parent);
if (new_bs->quiesce_counter && child->role->drained_begin) {
- child->role->drained_begin(child);
+ for (i = 0; i < new_bs->quiesce_counter; i++) {
+ child->role->drained_begin(child);
+ }
}
+ /* Attach only after starting new drained sections, so that recursive
+ * drain sections coming from @child don't get an extra .drained_begin
+ * callback. */
if (child->role->attach) {
child->role->attach(child);
}
@@ -2731,6 +2766,7 @@ BlockDriverState *bdrv_open(const char *filename, const char *reference,
* returns a pointer to bs_queue, which is either the newly allocated
* bs_queue, or the existing bs_queue being used.
*
+ * bs must be drained between bdrv_reopen_queue() and bdrv_reopen_multiple().
*/
static BlockReopenQueue *bdrv_reopen_queue_child(BlockReopenQueue *bs_queue,
BlockDriverState *bs,
@@ -2746,6 +2782,11 @@ static BlockReopenQueue *bdrv_reopen_queue_child(BlockReopenQueue *bs_queue,
BdrvChild *child;
QDict *old_options, *explicit_options;
+ /* Make sure that the caller remembered to use a drained section. This is
+ * important to avoid graph changes between the recursive queuing here and
+ * bdrv_reopen_multiple(). */
+ assert(bs->quiesce_counter > 0);
+
if (bs_queue == NULL) {
bs_queue = g_new0(BlockReopenQueue, 1);
QSIMPLEQ_INIT(bs_queue);
@@ -2870,6 +2911,8 @@ BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue,
* If all devices prepare successfully, then the changes are committed
* to all devices.
*
+ * All affected nodes must be drained between bdrv_reopen_queue() and
+ * bdrv_reopen_multiple().
*/
int bdrv_reopen_multiple(AioContext *ctx, BlockReopenQueue *bs_queue, Error **errp)
{
@@ -2879,11 +2922,8 @@ int bdrv_reopen_multiple(AioContext *ctx, BlockReopenQueue *bs_queue, Error **er
assert(bs_queue != NULL);
- aio_context_release(ctx);
- bdrv_drain_all_begin();
- aio_context_acquire(ctx);
-
QSIMPLEQ_FOREACH(bs_entry, bs_queue, entry) {
+ assert(bs_entry->state.bs->quiesce_counter > 0);
if (bdrv_reopen_prepare(&bs_entry->state, bs_queue, &local_err)) {
error_propagate(errp, local_err);
goto cleanup;
@@ -2912,8 +2952,6 @@ cleanup:
}
g_free(bs_queue);
- bdrv_drain_all_end();
-
return ret;
}
@@ -2923,12 +2961,18 @@ int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp)
{
int ret = -1;
Error *local_err = NULL;
- BlockReopenQueue *queue = bdrv_reopen_queue(NULL, bs, NULL, bdrv_flags);
+ BlockReopenQueue *queue;
+
+ bdrv_subtree_drained_begin(bs);
+ queue = bdrv_reopen_queue(NULL, bs, NULL, bdrv_flags);
ret = bdrv_reopen_multiple(bdrv_get_aio_context(bs), queue, &local_err);
if (local_err != NULL) {
error_propagate(errp, local_err);
}
+
+ bdrv_subtree_drained_end(bs);
+
return ret;
}
@@ -4320,9 +4364,15 @@ int bdrv_inactivate_all(void)
BdrvNextIterator it;
int ret = 0;
int pass;
+ GSList *aio_ctxs = NULL, *ctx;
for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
- aio_context_acquire(bdrv_get_aio_context(bs));
+ AioContext *aio_context = bdrv_get_aio_context(bs);
+
+ if (!g_slist_find(aio_ctxs, aio_context)) {
+ aio_ctxs = g_slist_prepend(aio_ctxs, aio_context);
+ aio_context_acquire(aio_context);
+ }
}
/* We do two passes of inactivation. The first pass calls to drivers'
@@ -4340,9 +4390,11 @@ int bdrv_inactivate_all(void)
}
out:
- for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
- aio_context_release(bdrv_get_aio_context(bs));
+ for (ctx = aio_ctxs; ctx != NULL; ctx = ctx->next) {
+ AioContext *aio_context = ctx->data;
+ aio_context_release(aio_context);
}
+ g_slist_free(aio_ctxs);
return ret;
}
@@ -4593,10 +4645,11 @@ void bdrv_img_create(const char *filename, const char *fmt,
back_flags = flags;
back_flags &= ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING);
+ backing_options = qdict_new();
if (backing_fmt) {
- backing_options = qdict_new();
qdict_put_str(backing_options, "driver", backing_fmt);
}
+ qdict_put_bool(backing_options, BDRV_OPT_FORCE_SHARE, true);
bs = bdrv_open(full_backing, NULL, backing_options, back_flags,
&local_err);
@@ -4746,7 +4799,7 @@ void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context)
AioContext *ctx = bdrv_get_aio_context(bs);
aio_disable_external(ctx);
- bdrv_parent_drained_begin(bs);
+ bdrv_parent_drained_begin(bs, NULL);
bdrv_drain(bs); /* ensure there are no in-flight requests */
while (aio_poll(ctx, false)) {
@@ -4760,7 +4813,7 @@ void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context)
*/
aio_context_acquire(new_context);
bdrv_attach_aio_context(bs, new_context);
- bdrv_parent_drained_end(bs);
+ bdrv_parent_drained_end(bs, NULL);
aio_enable_external(ctx);
aio_context_release(new_context);
}