return ret;
}
-void bdrv_append_temp_snapshot(BlockDriverState *bs, int flags, Error **errp)
+int bdrv_append_temp_snapshot(BlockDriverState *bs, int flags, Error **errp)
{
/* TODO: extra byte is a hack to ensure MAX_PATH space on Windows. */
char *tmp_filename = g_malloc0(PATH_MAX + 1);
/* Get the required size from the image */
total_size = bdrv_getlength(bs);
if (total_size < 0) {
+ ret = total_size;
error_setg_errno(errp, -total_size, "Could not get image size");
goto out;
}
out:
g_free(tmp_filename);
+ return ret;
}
/*
/* For snapshot=on, create a temporary qcow2 overlay. bs points to the
* temporary snapshot afterwards. */
if (snapshot_flags) {
- bdrv_append_temp_snapshot(bs, snapshot_flags, &local_err);
+ ret = bdrv_append_temp_snapshot(bs, snapshot_flags, &local_err);
if (local_err) {
- error_propagate(errp, local_err);
goto close_and_fail;
}
}
bool bs_busy;
aio_context_acquire(aio_context);
+ bdrv_flush_io_queue(bs);
bdrv_start_throttled_reqs(bs);
bs_busy = bdrv_requests_pending(bs);
bs_busy |= aio_poll(aio_context, bs_busy);
*
* Returns NULL if bs is not found in active's image chain,
* or if active == bs.
+ *
+ * Returns the bottommost base image if bs == NULL.
*/
BlockDriverState *bdrv_find_overlay(BlockDriverState *active,
BlockDriverState *bs)
{
- BlockDriverState *overlay = NULL;
- BlockDriverState *intermediate;
-
- assert(active != NULL);
- assert(bs != NULL);
-
- /* if bs is the same as active, then by definition it has no overlay
- */
- if (active == bs) {
- return NULL;
+ while (active && bs != active->backing_hd) {
+ active = active->backing_hd;
}
- intermediate = active;
- while (intermediate->backing_hd) {
- if (intermediate->backing_hd == bs) {
- overlay = intermediate;
- break;
- }
- intermediate = intermediate->backing_hd;
- }
+ return active;
+}
- return overlay;
+/* Given a BDS, searches for the base layer. */
+BlockDriverState *bdrv_find_base(BlockDriverState *bs)
+{
+ return bdrv_find_overlay(bs, NULL);
}
typedef struct BlkIntermediateStates {
*
* base <- active
*
+ * If backing_file_str is non-NULL, it will be used when modifying top's
+ * overlay image metadata.
+ *
* Error conditions:
* if active == top, that is considered an error
*
*/
int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top,
- BlockDriverState *base)
+ BlockDriverState *base, const char *backing_file_str)
{
BlockDriverState *intermediate;
BlockDriverState *base_bs = NULL;
}
/* success - we can delete the intermediate states, and link top->base */
- ret = bdrv_change_backing_file(new_top_bs, base_bs->filename,
+ backing_file_str = backing_file_str ? backing_file_str : base_bs->filename;
+ ret = bdrv_change_backing_file(new_top_bs, backing_file_str,
base_bs->drv ? base_bs->drv->format_name : "");
if (ret) {
goto exit;
return -ENOTSUP;
if (bs->read_only)
return -EACCES;
- if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_RESIZE, NULL)) {
- return -EBUSY;
- }
+
ret = drv->bdrv_truncate(bs, offset);
if (ret == 0) {
ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);
return NULL;
}
+/* If 'base' is in the same chain as 'top', return true. Otherwise,
+ * return false. If either argument is NULL, return false. */
+bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base)
+{
+ while (top && top != base) {
+ top = top->backing_hd;
+ }
+
+ return top != NULL;
+}
+
BlockDriverState *bdrv_next(BlockDriverState *bs)
{
if (!bs) {
return 1 + bdrv_get_backing_file_depth(bs->backing_hd);
}
-BlockDriverState *bdrv_find_base(BlockDriverState *bs)
-{
- BlockDriverState *curr_bs = NULL;
-
- if (!bs) {
- return NULL;
- }
-
- curr_bs = bs;
-
- while (curr_bs->backing_hd) {
- curr_bs = curr_bs->backing_hd;
- }
- return curr_bs;
-}
-
/**************************************************************/
/* async I/Os */
return false;
}
+
+BlockDriverState *check_to_replace_node(const char *node_name, Error **errp)
+{
+ BlockDriverState *to_replace_bs = bdrv_find_node(node_name);
+ if (!to_replace_bs) {
+ error_setg(errp, "Node name '%s' not found", node_name);
+ return NULL;
+ }
+
+ if (bdrv_op_is_blocked(to_replace_bs, BLOCK_OP_TYPE_REPLACE, errp)) {
+ return NULL;
+ }
+
+ /* We don't want arbitrary node of the BDS chain to be replaced only the top
+ * most non filter in order to prevent data corruption.
+ * Another benefit is that this tests exclude backing files which are
+ * blocked by the backing blockers.
+ */
+ if (!bdrv_is_first_non_filter(to_replace_bs)) {
+ error_setg(errp, "Only top most non filter can be replaced");
+ return NULL;
+ }
+
+ return to_replace_bs;
+}
+
+void bdrv_io_plug(BlockDriverState *bs)
+{
+ BlockDriver *drv = bs->drv;
+ if (drv && drv->bdrv_io_plug) {
+ drv->bdrv_io_plug(bs);
+ } else if (bs->file) {
+ bdrv_io_plug(bs->file);
+ }
+}
+
+void bdrv_io_unplug(BlockDriverState *bs)
+{
+ BlockDriver *drv = bs->drv;
+ if (drv && drv->bdrv_io_unplug) {
+ drv->bdrv_io_unplug(bs);
+ } else if (bs->file) {
+ bdrv_io_unplug(bs->file);
+ }
+}
+
+void bdrv_flush_io_queue(BlockDriverState *bs)
+{
+ BlockDriver *drv = bs->drv;
+ if (drv && drv->bdrv_flush_io_queue) {
+ drv->bdrv_flush_io_queue(bs);
+ } else if (bs->file) {
+ bdrv_flush_io_queue(bs->file);
+ }
+}