[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-block] [PULL 18/58] block: Reuse bs as backing hd for drive-backup
From: |
Kevin Wolf |
Subject: |
[Qemu-block] [PULL 18/58] block: Reuse bs as backing hd for drive-backup sync=none |
Date: |
Thu, 11 May 2017 16:32:21 +0200 |
From: Fam Zheng <address@hidden>
Opening the backing image for the second time is bad, especially here
when it is also in use as the active image as the source. The
drive-backup job itself doesn't read from target->backing for COW,
instead it gets data from the write notifier, so it's not a big problem.
However, exporting the target to NBD etc. won't work, because of the
likely stale metadata cache.
Use BDRV_O_NO_BACKING in this case and manually set up the backing
BdrvChild.
Cc: address@hidden
Signed-off-by: Fam Zheng <address@hidden>
Signed-off-by: Kevin Wolf <address@hidden>
---
blockdev.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/blockdev.c b/blockdev.c
index 0b38c3d..0d3773b 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -3151,6 +3151,7 @@ static BlockJob *do_drive_backup(DriveBackup *backup,
BlockJobTxn *txn,
Error *local_err = NULL;
int flags;
int64_t size;
+ bool set_backing_hd = false;
if (!backup->has_speed) {
backup->speed = 0;
@@ -3201,6 +3202,8 @@ static BlockJob *do_drive_backup(DriveBackup *backup,
BlockJobTxn *txn,
}
if (backup->sync == MIRROR_SYNC_MODE_NONE) {
source = bs;
+ flags |= BDRV_O_NO_BACKING;
+ set_backing_hd = true;
}
size = bdrv_getlength(bs);
@@ -3227,7 +3230,9 @@ static BlockJob *do_drive_backup(DriveBackup *backup,
BlockJobTxn *txn,
}
if (backup->format) {
- options = qdict_new();
+ if (!options) {
+ options = qdict_new();
+ }
qdict_put_str(options, "driver", backup->format);
}
@@ -3238,6 +3243,14 @@ static BlockJob *do_drive_backup(DriveBackup *backup,
BlockJobTxn *txn,
bdrv_set_aio_context(target_bs, aio_context);
+ if (set_backing_hd) {
+ bdrv_set_backing_hd(target_bs, source, &local_err);
+ if (local_err) {
+ bdrv_unref(target_bs);
+ goto out;
+ }
+ }
+
if (backup->has_bitmap) {
bmap = bdrv_find_dirty_bitmap(bs, backup->bitmap);
if (!bmap) {
--
1.8.3.1
- [Qemu-block] [PULL 08/58] iotests: 046: Prepare for image locking, (continued)
- [Qemu-block] [PULL 08/58] iotests: 046: Prepare for image locking, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 07/58] iotests: 030: Prepare for image locking, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 10/58] iotests: 085: Avoid image locking conflict, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 11/58] iotests: 087: Don't attach test image twice, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 12/58] iotests: 091: Quit QEMU before checking image, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 13/58] iotests: 172: Use separate images for multiple devices, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 17/58] tests: Disable image lock in test-replication, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 16/58] file-win32: Error out if locking=on, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 14/58] tests: Use null-co:// instead of /dev/null as the dummy image, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 15/58] file-posix: Add 'locking' option, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 18/58] block: Reuse bs as backing hd for drive-backup sync=none,
Kevin Wolf <=
- [Qemu-block] [PULL 19/58] osdep: Add qemu_lock_fd and qemu_unlock_fd, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 20/58] osdep: Fall back to posix lock when OFD lock is unavailable, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 22/58] qemu-iotests: Add test case 153 for image locking, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 23/58] tests: Add POSIX image locking test case 182, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 24/58] qcow2: Fix preallocation size formula, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 21/58] file-posix: Add image locking to perm operations, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 25/58] qcow2: Reuse preallocated zero clusters, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 26/58] qcow2: Discard preallocated zero clusters, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 27/58] iotests: Extend test 066, Kevin Wolf, 2017/05/11
- [Qemu-block] [PULL 28/58] migration: Unify block node activation error handling, Kevin Wolf, 2017/05/11