static QLIST_HEAD(, BlockDriver) bdrv_drivers =
QLIST_HEAD_INITIALIZER(bdrv_drivers);
-static int bdrv_open_inherit(BlockDriverState **pbs, const char *filename,
- const char *reference, QDict *options, int flags,
- BlockDriverState *parent,
- const BdrvChildRole *child_role, Error **errp);
+static BlockDriverState *bdrv_open_inherit(const char *filename,
+ const char *reference,
+ QDict *options, int flags,
+ BlockDriverState *parent,
+ const BdrvChildRole *child_role,
+ Error **errp);
/* If non-zero, use only whitelisted block drivers */
static int use_bdrv_whitelist;
-static void bdrv_close(BlockDriverState *bs);
-
#ifdef _WIN32
static int is_windows_drive_prefix(const char *filename)
{
return 0;
}
+static void bdrv_child_cb_drained_begin(BdrvChild *child)
+{
+ BlockDriverState *bs = child->opaque;
+ bdrv_drained_begin(bs);
+}
+
+static void bdrv_child_cb_drained_end(BdrvChild *child)
+{
+ BlockDriverState *bs = child->opaque;
+ bdrv_drained_end(bs);
+}
+
/*
* Returns the options and flags that a temporary snapshot should get, based on
* the originally requested flags (the originally requested image will have
/* 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;
}
/*
const BdrvChildRole child_file = {
.inherit_options = bdrv_inherited_options,
+ .drained_begin = bdrv_child_cb_drained_begin,
+ .drained_end = bdrv_child_cb_drained_end,
};
/*
const BdrvChildRole child_format = {
.inherit_options = bdrv_inherited_fmt_options,
+ .drained_begin = bdrv_child_cb_drained_begin,
+ .drained_end = bdrv_child_cb_drained_end,
};
/*
static const BdrvChildRole child_backing = {
.inherit_options = bdrv_backing_options,
+ .drained_begin = bdrv_child_cb_drained_begin,
+ .drained_end = bdrv_child_cb_drained_end,
};
static int bdrv_open_flags(BlockDriverState *bs, int flags)
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)) {
assert(bdrv_opt_mem_align(bs) != 0);
assert(bdrv_min_mem_align(bs) != 0);
- assert((bs->request_alignment != 0) || bdrv_is_sg(bs));
+ assert(is_power_of_2(bs->request_alignment) || bdrv_is_sg(bs));
qemu_opts_del(opts);
return 0;
return 0;
}
+static void bdrv_replace_child(BdrvChild *child, BlockDriverState *new_bs)
+{
+ BlockDriverState *old_bs = child->bs;
+
+ if (old_bs) {
+ if (old_bs->quiesce_counter && child->role->drained_end) {
+ child->role->drained_end(child);
+ }
+ QLIST_REMOVE(child, next_parent);
+ }
+
+ child->bs = new_bs;
+
+ 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);
+ }
+ }
+}
+
BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs,
const char *child_name,
- const BdrvChildRole *child_role)
+ const BdrvChildRole *child_role,
+ void *opaque)
{
BdrvChild *child = g_new(BdrvChild, 1);
*child = (BdrvChild) {
- .bs = child_bs,
+ .bs = NULL,
.name = g_strdup(child_name),
.role = child_role,
+ .opaque = opaque,
};
- QLIST_INSERT_HEAD(&child_bs->parents, child, next_parent);
+ bdrv_replace_child(child, child_bs);
return child;
}
const char *child_name,
const BdrvChildRole *child_role)
{
- BdrvChild *child = bdrv_root_attach_child(child_bs, child_name, child_role);
+ BdrvChild *child = bdrv_root_attach_child(child_bs, child_name, child_role,
+ parent_bs);
QLIST_INSERT_HEAD(&parent_bs->children, child, next);
return child;
}
QLIST_REMOVE(child, next);
child->next.le_prev = NULL;
}
- QLIST_REMOVE(child, next_parent);
+
+ bdrv_replace_child(child, NULL);
+
g_free(child->name);
g_free(child);
}
qdict_put(options, "driver", qstring_from_str(bs->backing_format));
}
- backing_hd = NULL;
- ret = bdrv_open_inherit(&backing_hd,
- *backing_filename ? backing_filename : NULL,
- reference, options, 0, bs, &child_backing,
- errp);
- if (ret < 0) {
+ backing_hd = bdrv_open_inherit(*backing_filename ? backing_filename : NULL,
+ reference, options, 0, bs, &child_backing,
+ errp);
+ if (!backing_hd) {
bs->open_flags |= BDRV_O_NO_BACKING;
error_prepend(errp, "Could not open backing file: ");
+ ret = -EINVAL;
goto free_exit;
}
BdrvChild *c = NULL;
BlockDriverState *bs;
QDict *image_options;
- int ret;
char *bdref_key_dot;
const char *reference;
goto done;
}
- bs = NULL;
- ret = bdrv_open_inherit(&bs, filename, reference, image_options, 0,
- parent, child_role, errp);
- if (ret < 0) {
+ bs = bdrv_open_inherit(filename, reference, image_options, 0,
+ parent, child_role, errp);
+ if (!bs) {
goto done;
}
int64_t total_size;
QemuOpts *opts = NULL;
BlockDriverState *bs_snapshot;
- Error *local_err = NULL;
int ret;
/* if snapshot, we create a temporary backing file and open it
qdict_put(snapshot_options, "driver",
qstring_from_str("qcow2"));
- bs_snapshot = NULL;
- ret = bdrv_open(&bs_snapshot, NULL, NULL, snapshot_options,
- flags, &local_err);
+ bs_snapshot = bdrv_open(NULL, NULL, snapshot_options, flags, errp);
snapshot_options = NULL;
- if (ret < 0) {
- error_propagate(errp, local_err);
+ if (!bs_snapshot) {
+ ret = -EINVAL;
goto out;
}
* should be opened. If specified, neither options nor a filename may be given,
* nor can an existing BDS be reused (that is, *pbs has to be NULL).
*/
-static int bdrv_open_inherit(BlockDriverState **pbs, const char *filename,
- const char *reference, QDict *options, int flags,
- BlockDriverState *parent,
- const BdrvChildRole *child_role, Error **errp)
+static BlockDriverState *bdrv_open_inherit(const char *filename,
+ const char *reference,
+ QDict *options, int flags,
+ BlockDriverState *parent,
+ const BdrvChildRole *child_role,
+ Error **errp)
{
int ret;
BdrvChild *file = NULL;
QDict *snapshot_options = NULL;
int snapshot_flags = 0;
- assert(pbs);
assert(!child_role || !flags);
assert(!child_role == !parent);
bool options_non_empty = options ? qdict_size(options) : false;
QDECREF(options);
- if (*pbs) {
- error_setg(errp, "Cannot reuse an existing BDS when referencing "
- "another block device");
- return -EINVAL;
- }
-
if (filename || options_non_empty) {
error_setg(errp, "Cannot reference an existing block device with "
"additional options or a new filename");
- return -EINVAL;
+ return NULL;
}
bs = bdrv_lookup_bs(reference, reference, errp);
if (!bs) {
- return -ENODEV;
+ return NULL;
}
bdrv_ref(bs);
- *pbs = bs;
- return 0;
+ return bs;
}
- if (*pbs) {
- bs = *pbs;
- } else {
- bs = bdrv_new();
- }
+ bs = bdrv_new();
/* NULL means an empty set of options */
if (options == NULL) {
/* json: syntax counts as explicit options, as if in the QDict */
parse_json_protocol(options, &filename, &local_err);
if (local_err) {
- ret = -EINVAL;
goto fail;
}
drv = bdrv_find_format(drvname);
if (!drv) {
error_setg(errp, "Unknown driver: '%s'", drvname);
- ret = -EINVAL;
goto fail;
}
}
file = bdrv_open_child(filename, options, "file", bs,
&child_file, true, &local_err);
if (local_err) {
- ret = -EINVAL;
goto fail;
}
}
qdict_put(options, "driver", qstring_from_str(drv->format_name));
} else if (!drv) {
error_setg(errp, "Must specify either driver or file");
- ret = -EINVAL;
goto fail;
}
drv->format_name, entry->key);
}
- ret = -EINVAL;
goto close_and_fail;
}
&& !runstate_check(RUN_STATE_PAUSED)) { /* HACK */
error_setg(errp,
"Guest must be stopped for opening of encrypted image");
- ret = -EBUSY;
goto close_and_fail;
}
snapshot_options, &local_err);
snapshot_options = NULL;
if (local_err) {
- ret = -EINVAL;
goto close_and_fail;
}
- if (!*pbs) {
- /* We are not going to return bs but the overlay on top of it
- * (snapshot_bs); thus, we have to drop the strong reference to bs
- * (which we obtained by calling bdrv_new()). bs will not be
- * deleted, though, because the overlay still has a reference to it.
- */
- bdrv_unref(bs);
- bs = snapshot_bs;
- } else {
- /* We are not going to return snapshot_bs, so we have to drop the
- * strong reference to it (which was returned by
- * bdrv_append_temp_snapshot()). snapshot_bs will not be deleted,
- * though, because bdrv_append_temp_snapshot() made all parental
- * references to bs (*pbs) point to snapshot_bs.
- * In fact, if *pbs was not NULL, we are not going to return any new
- * BDS. But we do not need to decrement bs's refcount here as is
- * done above, because with a non-NULL *pbs this function never even
- * had a strong reference to bs. */
- bdrv_unref(snapshot_bs);
- }
- }
-
- if (!*pbs) {
- *pbs = bs;
+ /* We are not going to return bs but the overlay on top of it
+ * (snapshot_bs); thus, we have to drop the strong reference to bs
+ * (which we obtained by calling bdrv_new()). bs will not be deleted,
+ * though, because the overlay still has a reference to it. */
+ bdrv_unref(bs);
+ bs = snapshot_bs;
}
- return 0;
+ return bs;
fail:
if (file != NULL) {
QDECREF(bs->options);
QDECREF(options);
bs->options = NULL;
- if (!*pbs) {
- /* If *pbs is NULL, a new BDS has been created in this function and
- needs to be freed now. Otherwise, it does not need to be closed,
- since it has not really been opened yet. */
- bdrv_unref(bs);
- }
+ bdrv_unref(bs);
if (local_err) {
error_propagate(errp, local_err);
}
- return ret;
+ return NULL;
close_and_fail:
- /* See fail path, but now the BDS has to be always closed */
- if (*pbs) {
- bdrv_close(bs);
- } else {
- bdrv_unref(bs);
- }
+ bdrv_unref(bs);
QDECREF(snapshot_options);
QDECREF(options);
if (local_err) {
error_propagate(errp, local_err);
}
- return ret;
+ return NULL;
}
-int bdrv_open(BlockDriverState **pbs, const char *filename,
- const char *reference, QDict *options, int flags, Error **errp)
+BlockDriverState *bdrv_open(const char *filename, const char *reference,
+ QDict *options, int flags, Error **errp)
{
- return bdrv_open_inherit(pbs, filename, reference, options, flags, NULL,
+ return bdrv_open_inherit(filename, reference, options, flags, NULL,
NULL, errp);
}
BdrvAioNotifier *ban, *ban_next;
assert(!bs->job);
+ assert(!bs->refcnt);
bdrv_drained_begin(bs); /* complete I/O */
bdrv_flush(bs);
bdrv_release_named_dirty_bitmaps(bs);
assert(QLIST_EMPTY(&bs->dirty_bitmaps));
- bdrv_parent_cb_change_media(bs, false);
-
if (bs->drv) {
BdrvChild *child, *next;
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;
void bdrv_close_all(void)
{
- BlockDriverState *bs;
- AioContext *aio_context;
+ block_job_cancel_sync_all();
/* Drop references from requests still in flight, such as canceled block
* jobs whose AIO context has not been polled yet */
blk_remove_all_bs();
blockdev_close_all_bdrv_states();
- /* Cancel all block jobs */
- while (!QTAILQ_EMPTY(&all_bdrv_states)) {
- QTAILQ_FOREACH(bs, &all_bdrv_states, bs_list) {
- aio_context = bdrv_get_aio_context(bs);
-
- aio_context_acquire(aio_context);
- if (bs->job) {
- block_job_cancel_sync(bs->job);
- aio_context_release(aio_context);
- break;
- }
- aio_context_release(aio_context);
- }
-
- /* All the remaining BlockDriverStates are referenced directly or
- * indirectly from block jobs, so there needs to be at least one BDS
- * directly used by a block job */
- assert(bs);
- }
+ assert(QTAILQ_EMPTY(&all_bdrv_states));
}
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);
- c->bs = to;
- QLIST_REMOVE(c, next_parent);
- QLIST_INSERT_HEAD(&to->parents, c, next_parent);
bdrv_ref(to);
+ bdrv_replace_child(c, to);
bdrv_unref(from);
}
}
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);
}
qstring_from_str(backing_fmt));
}
- bs = NULL;
- ret = bdrv_open(&bs, full_backing, NULL, backing_options,
- back_flags, &local_err);
+ bs = bdrv_open(full_backing, NULL, backing_options, back_flags,
+ &local_err);
g_free(full_backing);
- if (ret < 0) {
+ if (!bs) {
goto out;
}
size = bdrv_getlength(bs);
projects / mirror_qemu.git / blobdiff