static QLIST_HEAD(, BlockDriver) bdrv_drivers =
QLIST_HEAD_INITIALIZER(bdrv_drivers);
+/* The device to use for VM snapshots */
+static BlockDriverState *bs_snapshots;
+
/* If non-zero, use only whitelisted block drivers */
static int use_bdrv_whitelist;
char protocol[128];
int len;
const char *p;
- int is_drive;
/* TODO Drivers without bdrv_file_open must be specified explicitly */
+ /*
+ * XXX(hch): we really should not let host device detection
+ * override an explicit protocol specification, but moving this
+ * later breaks access to device names with colons in them.
+ * Thanks to the brain-dead persistent naming schemes on udev-
+ * based Linux systems those actually are quite common.
+ */
+ drv1 = find_hdev_driver(filename);
+ if (drv1) {
+ return drv1;
+ }
+
#ifdef _WIN32
- is_drive = is_windows_drive(filename) ||
- is_windows_drive_prefix(filename);
-#else
- is_drive = 0;
+ if (is_windows_drive(filename) ||
+ is_windows_drive_prefix(filename))
+ return bdrv_find_format("file");
#endif
+
p = strchr(filename, ':');
- if (!p || is_drive) {
- drv1 = find_hdev_driver(filename);
- if (!drv1) {
- drv1 = bdrv_find_format("file");
- }
- return drv1;
+ if (!p) {
+ return bdrv_find_format("file");
}
len = p - filename;
if (len > sizeof(protocol) - 1)
bs->file = NULL;
bs->total_sectors = 0;
- bs->is_temporary = 0;
bs->encrypted = 0;
bs->valid_key = 0;
bs->open_flags = flags;
void bdrv_close(BlockDriverState *bs)
{
if (bs->drv) {
+ if (bs == bs_snapshots) {
+ bs_snapshots = NULL;
+ }
if (bs->backing_hd) {
bdrv_delete(bs->backing_hd);
bs->backing_hd = NULL;
void bdrv_delete(BlockDriverState *bs)
{
+ assert(!bs->peer);
+
/* remove from list, if necessary */
if (bs->device_name[0] != '\0') {
QTAILQ_REMOVE(&bdrv_states, bs, list);
bdrv_delete(bs->file);
}
+ assert(bs != bs_snapshots);
qemu_free(bs);
}
+int bdrv_attach(BlockDriverState *bs, DeviceState *qdev)
+{
+ if (bs->peer) {
+ return -EBUSY;
+ }
+ bs->peer = qdev;
+ return 0;
+}
+
+void bdrv_detach(BlockDriverState *bs, DeviceState *qdev)
+{
+ assert(bs->peer == qdev);
+ bs->peer = NULL;
+}
+
+DeviceState *bdrv_get_attached(BlockDriverState *bs)
+{
+ return bs->peer;
+}
+
/*
* Run consistency checks on an image
*
- * Returns the number of errors or -errno when an internal error occurs
+ * Returns 0 if the check could be completed (it doesn't mean that the image is
+ * free of errors) or -errno when an internal error occured. The results of the
+ * check are stored in res.
*/
-int bdrv_check(BlockDriverState *bs)
+int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res)
{
if (bs->drv->bdrv_check == NULL) {
return -ENOTSUP;
}
- return bs->drv->bdrv_check(bs);
+ memset(res, 0, sizeof(*res));
+ return bs->drv->bdrv_check(bs, res);
}
/* commit COW file into the raw image */
return ret;
}
+void bdrv_commit_all(void)
+{
+ BlockDriverState *bs;
+
+ QTAILQ_FOREACH(bs, &bdrv_states, list) {
+ bdrv_commit(bs);
+ }
+}
+
/*
* Return values:
* 0 - success
return count1;
}
+/*
+ * Writes to the file and ensures that no writes are reordered across this
+ * request (acts as a barrier)
+ *
+ * Returns 0 on success, -errno in error cases.
+ */
+int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset,
+ const void *buf, int count)
+{
+ int ret;
+
+ ret = bdrv_pwrite(bs, offset, buf, count);
+ if (ret < 0) {
+ return ret;
+ }
+
+ /* No flush needed for cache=writethrough, it uses O_DSYNC */
+ if ((bs->open_flags & BDRV_O_CACHE_MASK) != 0) {
+ bdrv_flush(bs);
+ }
+
+ return 0;
+}
+
+/*
+ * Writes to the file and ensures that no writes are reordered across this
+ * request (acts as a barrier)
+ *
+ * Returns 0 on success, -errno in error cases.
+ */
+int bdrv_write_sync(BlockDriverState *bs, int64_t sector_num,
+ const uint8_t *buf, int nb_sectors)
+{
+ return bdrv_pwrite_sync(bs, BDRV_SECTOR_SIZE * sector_num,
+ buf, BDRV_SECTOR_SIZE * nb_sectors);
+}
+
/**
* Truncate file to 'offset' bytes (needed only for file protocols)
*/
return bs->translation;
}
+void bdrv_set_on_error(BlockDriverState *bs, BlockErrorAction on_read_error,
+ BlockErrorAction on_write_error)
+{
+ bs->on_read_error = on_read_error;
+ bs->on_write_error = on_write_error;
+}
+
+BlockErrorAction bdrv_get_on_error(BlockDriverState *bs, int is_read)
+{
+ return is_read ? bs->on_read_error : bs->on_write_error;
+}
+
+void bdrv_set_removable(BlockDriverState *bs, int removable)
+{
+ bs->removable = removable;
+ if (removable && bs == bs_snapshots) {
+ bs_snapshots = NULL;
+ }
+}
+
int bdrv_is_removable(BlockDriverState *bs)
{
return bs->removable;
return NULL;
}
+BlockDriverState *bdrv_next(BlockDriverState *bs)
+{
+ if (!bs) {
+ return QTAILQ_FIRST(&bdrv_states);
+ }
+ return QTAILQ_NEXT(bs, list);
+}
+
void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs), void *opaque)
{
BlockDriverState *bs;
"} }",
bs->rd_bytes, bs->wr_bytes,
bs->rd_ops, bs->wr_ops,
- bs->wr_highest_sector * (long)BDRV_SECTOR_SIZE);
+ bs->wr_highest_sector *
+ (uint64_t)BDRV_SECTOR_SIZE);
dict = qobject_to_qdict(res);
if (*bs->device_name) {
return 1;
}
+BlockDriverState *bdrv_snapshots(void)
+{
+ BlockDriverState *bs;
+
+ if (bs_snapshots) {
+ return bs_snapshots;
+ }
+
+ bs = NULL;
+ while ((bs = bdrv_next(bs))) {
+ if (bdrv_can_snapshot(bs)) {
+ bs_snapshots = bs;
+ return bs;
+ }
+ }
+ return NULL;
+}
+
int bdrv_snapshot_create(BlockDriverState *bs,
QEMUSnapshotInfo *sn_info)
{
if (ret < 0 && !mcb->error) {
mcb->error = ret;
- multiwrite_user_cb(mcb);
}
mcb->num_requests--;
if (mcb->num_requests == 0) {
- if (mcb->error == 0) {
- multiwrite_user_cb(mcb);
- }
+ multiwrite_user_cb(mcb);
qemu_free(mcb);
}
}
// Check for mergable requests
num_reqs = multiwrite_merge(bs, reqs, num_reqs, mcb);
- // Run the aio requests
+ /*
+ * Run the aio requests. As soon as one request can't be submitted
+ * successfully, fail all requests that are not yet submitted (we must
+ * return failure for all requests anyway)
+ *
+ * num_requests cannot be set to the right value immediately: If
+ * bdrv_aio_writev fails for some request, num_requests would be too high
+ * and therefore multiwrite_cb() would never recognize the multiwrite
+ * request as completed. We also cannot use the loop variable i to set it
+ * when the first request fails because the callback may already have been
+ * called for previously submitted requests. Thus, num_requests must be
+ * incremented for each request that is submitted.
+ *
+ * The problem that callbacks may be called early also means that we need
+ * to take care that num_requests doesn't become 0 before all requests are
+ * submitted - multiwrite_cb() would consider the multiwrite request
+ * completed. A dummy request that is "completed" by a manual call to
+ * multiwrite_cb() takes care of this.
+ */
+ mcb->num_requests = 1;
+
for (i = 0; i < num_reqs; i++) {
+ mcb->num_requests++;
acb = bdrv_aio_writev(bs, reqs[i].sector, reqs[i].qiov,
reqs[i].nb_sectors, multiwrite_cb, mcb);
// We can only fail the whole thing if no request has been
// submitted yet. Otherwise we'll wait for the submitted AIOs to
// complete and report the error in the callback.
- if (mcb->num_requests == 0) {
- reqs[i].error = -EIO;
+ if (i == 0) {
goto fail;
} else {
- mcb->num_requests++;
multiwrite_cb(mcb, -EIO);
break;
}
- } else {
- mcb->num_requests++;
}
}
+ /* Complete the dummy request */
+ multiwrite_cb(mcb, 0);
+
return 0;
fail:
+ for (i = 0; i < mcb->num_callbacks; i++) {
+ reqs[i].error = -EIO;
+ }
qemu_free(mcb);
return -1;
}
projects / qemu.git / blobdiff