return 0;
}
+/**
+ * Set open flags for a given discard mode
+ *
+ * Return 0 on success, -1 if the discard mode was invalid.
+ */
+int bdrv_parse_discard_flags(const char *mode, int *flags)
+{
+ *flags &= ~BDRV_O_UNMAP;
+
+ if (!strcmp(mode, "off") || !strcmp(mode, "ignore")) {
+ /* do nothing */
+ } else if (!strcmp(mode, "on") || !strcmp(mode, "unmap")) {
+ *flags |= BDRV_O_UNMAP;
+ } else {
+ return -1;
+ }
+
+ return 0;
+}
+
/**
* Set open flags for a given cache mode
*
BlockDriverState *bs;
QTAILQ_FOREACH(bs, &bdrv_states, list) {
- int ret = bdrv_commit(bs);
- if (ret < 0) {
- return ret;
+ if (bs->drv && bs->backing_hd) {
+ int ret = bdrv_commit(bs);
+ if (ret < 0) {
+ return ret;
+ }
}
}
return 0;
return -EACCES;
if (bdrv_in_use(bs))
return -EBUSY;
+
+ /* There better not be any in-flight IOs when we truncate the device. */
+ bdrv_drain_all();
+
ret = drv->bdrv_truncate(bs, offset);
if (ret == 0) {
ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);
bdrv_reset_dirty(bs, sector_num, nb_sectors);
}
+ /* Do nothing if disabled. */
+ if (!(bs->open_flags & BDRV_O_UNMAP)) {
+ return 0;
+ }
+
if (bs->drv->bdrv_co_discard) {
return bs->drv->bdrv_co_discard(bs, sector_num, nb_sectors);
} else if (bs->drv->bdrv_aio_discard) {