* [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD
@ 2014-03-10 7:25 Fam Zheng
2014-03-10 7:25 ` [Qemu-devel] [PATCH v17 01/14] block: Add BlockOpType enum Fam Zheng
` (14 more replies)
0 siblings, 15 replies; 36+ messages in thread
From: Fam Zheng @ 2014-03-10 7:25 UTC (permalink / raw)
To: qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
This series adds for point-in-time snapshot NBD exporting based on
blockdev-backup (variant of drive-backup with existing device as target).
We get a thin point-in-time snapshot by COW mechanism of drive-backup, and
export it through built in NBD server. The steps are as below:
1. (SHELL) qemu-img create -f qcow2 BACKUP.qcow2 <source size here>
(Alternatively we can use -o backing_file=RUNNING-VM.img to omit explicitly
providing the size by ourselves, but it's risky because RUNNING-VM.qcow2 is
used r/w by guest. Whether or not setting backing file in the image file
doesn't matter, as we are going to override the backing hd in the next
step)
2. (QMP) blockdev-add backing=source-drive file.driver=file file.filename=BACKUP.qcow2 id=target0 if=none driver=qcow2
(where source-drive is the running BlockDriverState name for
RUNNING-VM.img. This patch implements "backing=" option to override
backing_hd for added drive)
3. (QMP) blockdev-backup device=source-drive sync=none target=target0
(this is the QMP command introduced by this series, which use a named
device as target of drive-backup)
4. (QMP) nbd-server-add device=target0
When image fleecing done:
1. (QMP) block-job-cancel device=source-drive
2. (HMP) drive_del target0
3. (SHELL) rm BACKUP.qcow2
v17: Rebase to current master.
v16: Address review comments from Jeff and Markus (thanks for reviewing!)
(A side-by-side diff of v15 -> v16: http://goo.gl/1goc6S)
[03/14] block: Replace in_use with operation blocker
Improve error message. (Markus)
[05/14] block: Add bdrv_set_backing_hd()
in bdrv_set_backing_hd:
* Don't call bdrv_ref and bdrv_unref. (Jeff)
* Add "bs->open_flags &= ~BDRV_O_NO_BACKING". (Jeff)
in bdrv_open_backing_file:
* Remove unnecessary "bs->backing_hd = NULL;". (Jeff)
* Don't get wrong refcnt on backing_hd. (Jeff)
in bdrv_append:
* Remove unnessary backing_file and backing_format copy, it's taken
care of in bdrv_set_backing_hd(). (Jeff)
[06/14] block: Add backing_blocker in BlockDriverState
Add call to bdrv_ref() since bdrv_set_backing_hd() doesn't do it
now.
[08/14] block: Support dropping active in bdrv_drop_intermediate
Verify active, top, base are in the same backing chain. (Jeff)
Remember to change backing file when base != NULL. (Jeff)
[09/14] stream: Use bdrv_drop_intermediate and drop close_unused_images
Drop more unnecessary code. (Jeff)
Thanks,
Fam
Fam Zheng (14):
block: Add BlockOpType enum
block: Introduce op_blockers to BlockDriverState
block: Replace in_use with operation blocker
block: Move op_blocker check from block_job_create to its caller
block: Add bdrv_set_backing_hd()
block: Add backing_blocker in BlockDriverState
block: Parse "backing" option to reference existing BDS
block: Support dropping active in bdrv_drop_intermediate
stream: Use bdrv_drop_intermediate and drop close_unused_images
qmp: Add command 'blockdev-backup'
block: Allow backup on referenced named BlockDriverState
block: Add blockdev-backup to transaction
qemu-iotests: Test blockdev-backup in 055
qemu-iotests: Image fleecing test case 083
block-migration.c | 7 +-
block.c | 314 +++++++++++++++++++++++++++-------------
block/backup.c | 26 ++++
block/commit.c | 2 +-
block/mirror.c | 1 +
block/stream.c | 42 +-----
blockdev.c | 122 ++++++++++++++--
blockjob.c | 14 +-
hw/block/dataplane/virtio-blk.c | 19 ++-
include/block/block.h | 29 +++-
include/block/block_int.h | 9 +-
include/block/blockjob.h | 3 +
qapi-schema.json | 50 +++++++
qmp-commands.hx | 44 ++++++
tests/qemu-iotests/055 | 275 +++++++++++++++++++++++++++++------
tests/qemu-iotests/055.out | 4 +-
tests/qemu-iotests/083 | 99 +++++++++++++
tests/qemu-iotests/083.out | 5 +
tests/qemu-iotests/group | 1 +
19 files changed, 854 insertions(+), 212 deletions(-)
create mode 100755 tests/qemu-iotests/083
create mode 100644 tests/qemu-iotests/083.out
--
1.9.0
^ permalink raw reply [flat|nested] 36+ messages in thread
* [Qemu-devel] [PATCH v17 01/14] block: Add BlockOpType enum
2014-03-10 7:25 [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
@ 2014-03-10 7:25 ` Fam Zheng
2014-04-06 23:47 ` Jeff Cody
2014-03-10 7:25 ` [Qemu-devel] [PATCH v17 02/14] block: Introduce op_blockers to BlockDriverState Fam Zheng
` (13 subsequent siblings)
14 siblings, 1 reply; 36+ messages in thread
From: Fam Zheng @ 2014-03-10 7:25 UTC (permalink / raw)
To: qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
This adds the enum of all the operations that can be taken on a block
device.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
---
include/block/block.h | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
diff --git a/include/block/block.h b/include/block/block.h
index 780f48b..8820735 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -154,6 +154,25 @@ typedef struct BDRVReopenState {
void *opaque;
} BDRVReopenState;
+/*
+ * Block operation types
+ */
+typedef enum BlockOpType {
+ BLOCK_OP_TYPE_BACKUP_SOURCE,
+ BLOCK_OP_TYPE_BACKUP_TARGET,
+ BLOCK_OP_TYPE_CHANGE,
+ BLOCK_OP_TYPE_COMMIT,
+ BLOCK_OP_TYPE_DATAPLANE,
+ BLOCK_OP_TYPE_DRIVE_DEL,
+ BLOCK_OP_TYPE_EJECT,
+ BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT,
+ BLOCK_OP_TYPE_INTERNAL_SNAPSHOT,
+ BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE,
+ BLOCK_OP_TYPE_MIRROR,
+ BLOCK_OP_TYPE_RESIZE,
+ BLOCK_OP_TYPE_STREAM,
+ BLOCK_OP_TYPE_MAX,
+} BlockOpType;
void bdrv_iostatus_enable(BlockDriverState *bs);
void bdrv_iostatus_reset(BlockDriverState *bs);
--
1.9.0
^ permalink raw reply related [flat|nested] 36+ messages in thread
* [Qemu-devel] [PATCH v17 02/14] block: Introduce op_blockers to BlockDriverState
2014-03-10 7:25 [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
2014-03-10 7:25 ` [Qemu-devel] [PATCH v17 01/14] block: Add BlockOpType enum Fam Zheng
@ 2014-03-10 7:25 ` Fam Zheng
2014-04-06 23:49 ` Jeff Cody
2014-03-10 7:25 ` [Qemu-devel] [PATCH v17 03/14] block: Replace in_use with operation blocker Fam Zheng
` (12 subsequent siblings)
14 siblings, 1 reply; 36+ messages in thread
From: Fam Zheng @ 2014-03-10 7:25 UTC (permalink / raw)
To: qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
BlockDriverState.op_blockers is an array of lists with BLOCK_OP_TYPE_MAX
elements. Each list is a list of blockers of an operation type
(BlockOpType), that marks this BDS as currently blocked for a certain
type of operation with reason errors stored in the list. The rule of
usage is:
* BDS user who wants to take an operation should check if there's any
blocker of the type with bdrv_op_is_blocked().
* BDS user who wants to block certain types of operation, should call
bdrv_op_block (or bdrv_op_block_all to block all types of operations,
which is similar to the existing bdrv_set_in_use()).
* A blocker is only referenced by op_blockers, so the lifecycle is
managed by caller, and shouldn't be lost until unblock, so typically
a caller does these:
- Allocate a blocker with error_setg or similar, call bdrv_op_block()
to block some operations.
- Hold the blocker, do his job.
- Unblock operations that it blocked, with the same reason pointer
passed to bdrv_op_unblock().
- Release the blocker with error_free().
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
---
block.c | 75 +++++++++++++++++++++++++++++++++++++++++++++++
include/block/block.h | 7 +++++
include/block/block_int.h | 5 ++++
3 files changed, 87 insertions(+)
diff --git a/block.c b/block.c
index f1ef4b0..56a4433 100644
--- a/block.c
+++ b/block.c
@@ -335,6 +335,7 @@ void bdrv_register(BlockDriver *bdrv)
BlockDriverState *bdrv_new(const char *device_name)
{
BlockDriverState *bs;
+ int i;
bs = g_malloc0(sizeof(BlockDriverState));
QLIST_INIT(&bs->dirty_bitmaps);
@@ -342,6 +343,9 @@ BlockDriverState *bdrv_new(const char *device_name)
if (device_name[0] != '\0') {
QTAILQ_INSERT_TAIL(&bdrv_states, bs, device_list);
}
+ for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) {
+ QLIST_INIT(&bs->op_blockers[i]);
+ }
bdrv_iostatus_disable(bs);
notifier_list_init(&bs->close_notifiers);
notifier_with_return_list_init(&bs->before_write_notifiers);
@@ -1853,6 +1857,8 @@ static void bdrv_move_feature_fields(BlockDriverState *bs_dest,
pstrcpy(bs_dest->device_name, sizeof(bs_dest->device_name),
bs_src->device_name);
bs_dest->device_list = bs_src->device_list;
+ memcpy(bs_dest->op_blockers, bs_src->op_blockers,
+ sizeof(bs_dest->op_blockers));
}
/*
@@ -5151,6 +5157,75 @@ void bdrv_unref(BlockDriverState *bs)
}
}
+struct BdrvOpBlocker {
+ Error *reason;
+ QLIST_ENTRY(BdrvOpBlocker) list;
+};
+
+bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp)
+{
+ BdrvOpBlocker *blocker;
+ assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX);
+ if (!QLIST_EMPTY(&bs->op_blockers[op])) {
+ blocker = QLIST_FIRST(&bs->op_blockers[op]);
+ if (errp) {
+ *errp = error_copy(blocker->reason);
+ }
+ return true;
+ }
+ return false;
+}
+
+void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason)
+{
+ BdrvOpBlocker *blocker;
+ assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX);
+
+ blocker = g_malloc0(sizeof(BdrvOpBlocker));
+ blocker->reason = reason;
+ QLIST_INSERT_HEAD(&bs->op_blockers[op], blocker, list);
+}
+
+void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason)
+{
+ BdrvOpBlocker *blocker, *next;
+ assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX);
+ QLIST_FOREACH_SAFE(blocker, &bs->op_blockers[op], list, next) {
+ if (blocker->reason == reason) {
+ QLIST_REMOVE(blocker, list);
+ g_free(blocker);
+ }
+ }
+}
+
+void bdrv_op_block_all(BlockDriverState *bs, Error *reason)
+{
+ int i;
+ for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) {
+ bdrv_op_block(bs, i, reason);
+ }
+}
+
+void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason)
+{
+ int i;
+ for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) {
+ bdrv_op_unblock(bs, i, reason);
+ }
+}
+
+bool bdrv_op_blocker_is_empty(BlockDriverState *bs)
+{
+ int i;
+
+ for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) {
+ if (!QLIST_EMPTY(&bs->op_blockers[i])) {
+ return false;
+ }
+ }
+ return true;
+}
+
void bdrv_set_in_use(BlockDriverState *bs, int in_use)
{
assert(bs->in_use != in_use);
diff --git a/include/block/block.h b/include/block/block.h
index 8820735..4874e2a 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -474,6 +474,13 @@ void bdrv_unref(BlockDriverState *bs);
void bdrv_set_in_use(BlockDriverState *bs, int in_use);
int bdrv_in_use(BlockDriverState *bs);
+bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp);
+void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason);
+void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason);
+void bdrv_op_block_all(BlockDriverState *bs, Error *reason);
+void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason);
+bool bdrv_op_blocker_is_empty(BlockDriverState *bs);
+
#ifdef CONFIG_LINUX_AIO
int raw_get_aio_fd(BlockDriverState *bs);
#else
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 0bcf1c9..4e558d0 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -270,6 +270,8 @@ typedef struct BlockLimits {
size_t opt_mem_alignment;
} BlockLimits;
+typedef struct BdrvOpBlocker BdrvOpBlocker;
+
/*
* Note: the function bdrv_append() copies and swaps contents of
* BlockDriverStates, so if you add new fields to this struct, please
@@ -361,6 +363,9 @@ struct BlockDriverState {
QLIST_HEAD(, BdrvTrackedRequest) tracked_requests;
+ /* operation blockers */
+ QLIST_HEAD(, BdrvOpBlocker) op_blockers[BLOCK_OP_TYPE_MAX];
+
/* long-running background operation */
BlockJob *job;
--
1.9.0
^ permalink raw reply related [flat|nested] 36+ messages in thread
* [Qemu-devel] [PATCH v17 03/14] block: Replace in_use with operation blocker
2014-03-10 7:25 [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
2014-03-10 7:25 ` [Qemu-devel] [PATCH v17 01/14] block: Add BlockOpType enum Fam Zheng
2014-03-10 7:25 ` [Qemu-devel] [PATCH v17 02/14] block: Introduce op_blockers to BlockDriverState Fam Zheng
@ 2014-03-10 7:25 ` Fam Zheng
2014-04-07 0:10 ` Jeff Cody
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 04/14] block: Move op_blocker check from block_job_create to its caller Fam Zheng
` (11 subsequent siblings)
14 siblings, 1 reply; 36+ messages in thread
From: Fam Zheng @ 2014-03-10 7:25 UTC (permalink / raw)
To: qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
This drops BlockDriverState.in_use with op_blockers:
- Call bdrv_op_block_all in place of bdrv_set_in_use(bs, 1).
- Call bdrv_op_unblock_all in place of bdrv_set_in_use(bs, 0).
- Check bdrv_op_is_blocked() in place of bdrv_in_use(bs).
The specific types are used, e.g. in place of starting block backup,
bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP, ...).
- Check bdrv_op_blocker_is_empty() in place of assert(!bs->in_use).
Note: there is only bdrv_op_block_all and bdrv_op_unblock_all callers at
this moment. So although the checks are specific to op types, this
changes can still be seen as identical logic with previously with
in_use. The difference is error message are improved because of blocker
error info.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
---
block-migration.c | 7 +++++--
block.c | 24 +++++++-----------------
blockdev.c | 19 +++++++++----------
blockjob.c | 14 +++++++++-----
hw/block/dataplane/virtio-blk.c | 19 ++++++++++++-------
include/block/block.h | 2 --
include/block/block_int.h | 1 -
include/block/blockjob.h | 3 +++
8 files changed, 45 insertions(+), 44 deletions(-)
diff --git a/block-migration.c b/block-migration.c
index 897fdba..bf9a25f 100644
--- a/block-migration.c
+++ b/block-migration.c
@@ -59,6 +59,7 @@ typedef struct BlkMigDevState {
unsigned long *aio_bitmap;
int64_t completed_sectors;
BdrvDirtyBitmap *dirty_bitmap;
+ Error *blocker;
} BlkMigDevState;
typedef struct BlkMigBlock {
@@ -346,7 +347,8 @@ static void init_blk_migration_it(void *opaque, BlockDriverState *bs)
bmds->completed_sectors = 0;
bmds->shared_base = block_mig_state.shared_base;
alloc_aio_bitmap(bmds);
- bdrv_set_in_use(bs, 1);
+ error_setg(&bmds->blocker, "block device is in use by migration");
+ bdrv_op_block_all(bs, bmds->blocker);
bdrv_ref(bs);
block_mig_state.total_sector_sum += sectors;
@@ -584,7 +586,8 @@ static void blk_mig_cleanup(void)
blk_mig_lock();
while ((bmds = QSIMPLEQ_FIRST(&block_mig_state.bmds_list)) != NULL) {
QSIMPLEQ_REMOVE_HEAD(&block_mig_state.bmds_list, entry);
- bdrv_set_in_use(bmds->bs, 0);
+ bdrv_op_unblock_all(bmds->bs, bmds->blocker);
+ error_free(bmds->blocker);
bdrv_unref(bmds->bs);
g_free(bmds->aio_bitmap);
g_free(bmds);
diff --git a/block.c b/block.c
index 56a4433..c79d5dc 100644
--- a/block.c
+++ b/block.c
@@ -1850,7 +1850,6 @@ static void bdrv_move_feature_fields(BlockDriverState *bs_dest,
bs_dest->refcnt = bs_src->refcnt;
/* job */
- bs_dest->in_use = bs_src->in_use;
bs_dest->job = bs_src->job;
/* keep the same entry in bdrv_states */
@@ -1893,7 +1892,7 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
assert(QLIST_EMPTY(&bs_new->dirty_bitmaps));
assert(bs_new->job == NULL);
assert(bs_new->dev == NULL);
- assert(bs_new->in_use == 0);
+ assert(bdrv_op_blocker_is_empty(bs_new));
assert(bs_new->io_limits_enabled == false);
assert(!throttle_have_timer(&bs_new->throttle_state));
@@ -1912,7 +1911,7 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
/* Check a few fields that should remain attached to the device */
assert(bs_new->dev == NULL);
assert(bs_new->job == NULL);
- assert(bs_new->in_use == 0);
+ assert(bdrv_op_blocker_is_empty(bs_new));
assert(bs_new->io_limits_enabled == false);
assert(!throttle_have_timer(&bs_new->throttle_state));
@@ -1957,7 +1956,7 @@ static void bdrv_delete(BlockDriverState *bs)
{
assert(!bs->dev);
assert(!bs->job);
- assert(!bs->in_use);
+ assert(bdrv_op_blocker_is_empty(bs));
assert(!bs->refcnt);
assert(QLIST_EMPTY(&bs->dirty_bitmaps));
@@ -2139,7 +2138,8 @@ int bdrv_commit(BlockDriverState *bs)
return -ENOTSUP;
}
- if (bdrv_in_use(bs) || bdrv_in_use(bs->backing_hd)) {
+ if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT, NULL) ||
+ bdrv_op_is_blocked(bs->backing_hd, BLOCK_OP_TYPE_COMMIT, NULL)) {
return -EBUSY;
}
@@ -3374,8 +3374,9 @@ int bdrv_truncate(BlockDriverState *bs, int64_t offset)
return -ENOTSUP;
if (bs->read_only)
return -EACCES;
- if (bdrv_in_use(bs))
+ 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);
@@ -5226,17 +5227,6 @@ bool bdrv_op_blocker_is_empty(BlockDriverState *bs)
return true;
}
-void bdrv_set_in_use(BlockDriverState *bs, int in_use)
-{
- assert(bs->in_use != in_use);
- bs->in_use = in_use;
-}
-
-int bdrv_in_use(BlockDriverState *bs)
-{
- return bs->in_use;
-}
-
void bdrv_iostatus_enable(BlockDriverState *bs)
{
bs->iostatus_enabled = true;
diff --git a/blockdev.c b/blockdev.c
index c3422a1..593925e 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1293,8 +1293,8 @@ static void external_snapshot_prepare(BlkTransactionState *common,
return;
}
- if (bdrv_in_use(state->old_bs)) {
- error_set(errp, QERR_DEVICE_IN_USE, device);
+ if (bdrv_op_is_blocked(state->old_bs,
+ BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, errp)) {
return;
}
@@ -1516,8 +1516,7 @@ exit:
static void eject_device(BlockDriverState *bs, int force, Error **errp)
{
- if (bdrv_in_use(bs)) {
- error_set(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
+ if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_EJECT, errp)) {
return;
}
if (!bdrv_dev_has_removable_media(bs)) {
@@ -1717,14 +1716,16 @@ int do_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data)
{
const char *id = qdict_get_str(qdict, "id");
BlockDriverState *bs;
+ Error *local_err = NULL;
bs = bdrv_find(id);
if (!bs) {
qerror_report(QERR_DEVICE_NOT_FOUND, id);
return -1;
}
- if (bdrv_in_use(bs)) {
- qerror_report(QERR_DEVICE_IN_USE, id);
+ if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_DRIVE_DEL, &local_err)) {
+ error_report("%s", error_get_pretty(local_err));
+ error_free(local_err);
return -1;
}
@@ -1976,8 +1977,7 @@ void qmp_drive_backup(const char *device, const char *target,
}
}
- if (bdrv_in_use(bs)) {
- error_set(errp, QERR_DEVICE_IN_USE, device);
+ if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
return;
}
@@ -2110,8 +2110,7 @@ void qmp_drive_mirror(const char *device, const char *target,
}
}
- if (bdrv_in_use(bs)) {
- error_set(errp, QERR_DEVICE_IN_USE, device);
+ if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR, errp)) {
return;
}
diff --git a/blockjob.c b/blockjob.c
index b3ce14c..f643a78 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -41,14 +41,16 @@ void *block_job_create(const BlockJobDriver *driver, BlockDriverState *bs,
{
BlockJob *job;
- if (bs->job || bdrv_in_use(bs)) {
+ if (bs->job || !bdrv_op_blocker_is_empty(bs)) {
error_set(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
return NULL;
}
bdrv_ref(bs);
- bdrv_set_in_use(bs, 1);
-
job = g_malloc0(driver->instance_size);
+ error_setg(&job->blocker, "block device is in use by block job: %s",
+ BlockJobType_lookup[driver->job_type]);
+ bdrv_op_block_all(bs, job->blocker);
+
job->driver = driver;
job->bs = bs;
job->cb = cb;
@@ -63,8 +65,9 @@ void *block_job_create(const BlockJobDriver *driver, BlockDriverState *bs,
block_job_set_speed(job, speed, &local_err);
if (local_err) {
bs->job = NULL;
+ bdrv_op_unblock_all(bs, job->blocker);
+ error_free(job->blocker);
g_free(job);
- bdrv_set_in_use(bs, 0);
error_propagate(errp, local_err);
return NULL;
}
@@ -79,8 +82,9 @@ void block_job_completed(BlockJob *job, int ret)
assert(bs->job == job);
job->cb(job->opaque, ret);
bs->job = NULL;
+ bdrv_op_unblock_all(bs, job->blocker);
+ error_free(job->blocker);
g_free(job);
- bdrv_set_in_use(bs, 0);
}
void block_job_set_speed(BlockJob *job, int64_t speed, Error **errp)
diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c
index 2237edb..cee0aa5 100644
--- a/hw/block/dataplane/virtio-blk.c
+++ b/hw/block/dataplane/virtio-blk.c
@@ -69,6 +69,9 @@ struct VirtIOBlockDataPlane {
queue */
unsigned int num_reqs;
+
+ /* Operation blocker on BDS */
+ Error *blocker;
};
/* Raise an interrupt to signal guest, if necessary */
@@ -368,6 +371,7 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *blk,
{
VirtIOBlockDataPlane *s;
int fd;
+ Error *local_err = NULL;
*dataplane = NULL;
@@ -390,9 +394,10 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *blk,
/* If dataplane is (re-)enabled while the guest is running there could be
* block jobs that can conflict.
*/
- if (bdrv_in_use(blk->conf.bs)) {
- error_setg(errp,
- "cannot start dataplane thread while device is in use");
+ if (bdrv_op_is_blocked(blk->conf.bs, BLOCK_OP_TYPE_DATAPLANE, &local_err)) {
+ error_report("cannot start dataplane thread: %s",
+ error_get_pretty(local_err));
+ error_free(local_err);
return;
}
@@ -407,9 +412,8 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *blk,
s->vdev = vdev;
s->fd = fd;
s->blk = blk;
-
- /* Prevent block operations that conflict with data plane thread */
- bdrv_set_in_use(blk->conf.bs, 1);
+ error_setg(&s->blocker, "block device is in use by data plane");
+ bdrv_op_block_all(blk->conf.bs, s->blocker);
*dataplane = s;
}
@@ -421,7 +425,8 @@ void virtio_blk_data_plane_destroy(VirtIOBlockDataPlane *s)
}
virtio_blk_data_plane_stop(s);
- bdrv_set_in_use(s->blk->conf.bs, 0);
+ bdrv_op_unblock_all(s->blk->conf.bs, s->blocker);
+ error_free(s->blocker);
g_free(s);
}
diff --git a/include/block/block.h b/include/block/block.h
index 4874e2a..a46f70a 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -471,8 +471,6 @@ void bdrv_disable_copy_on_read(BlockDriverState *bs);
void bdrv_ref(BlockDriverState *bs);
void bdrv_unref(BlockDriverState *bs);
-void bdrv_set_in_use(BlockDriverState *bs, int in_use);
-int bdrv_in_use(BlockDriverState *bs);
bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp);
void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason);
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 4e558d0..1d3f76f 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -359,7 +359,6 @@ struct BlockDriverState {
QTAILQ_ENTRY(BlockDriverState) device_list;
QLIST_HEAD(, BdrvDirtyBitmap) dirty_bitmaps;
int refcnt;
- int in_use; /* users other than guest access, eg. block migration */
QLIST_HEAD(, BdrvTrackedRequest) tracked_requests;
diff --git a/include/block/blockjob.h b/include/block/blockjob.h
index d76de62..c0a7875 100644
--- a/include/block/blockjob.h
+++ b/include/block/blockjob.h
@@ -106,6 +106,9 @@ struct BlockJob {
/** The completion function that will be called when the job completes. */
BlockDriverCompletionFunc *cb;
+ /** Block other operations when block job is running */
+ Error *blocker;
+
/** The opaque value that is passed to the completion function. */
void *opaque;
};
--
1.9.0
^ permalink raw reply related [flat|nested] 36+ messages in thread
* [Qemu-devel] [PATCH v17 04/14] block: Move op_blocker check from block_job_create to its caller
2014-03-10 7:25 [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
` (2 preceding siblings ...)
2014-03-10 7:25 ` [Qemu-devel] [PATCH v17 03/14] block: Replace in_use with operation blocker Fam Zheng
@ 2014-03-10 7:26 ` Fam Zheng
2014-04-06 23:50 ` Jeff Cody
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 05/14] block: Add bdrv_set_backing_hd() Fam Zheng
` (10 subsequent siblings)
14 siblings, 1 reply; 36+ messages in thread
From: Fam Zheng @ 2014-03-10 7:26 UTC (permalink / raw)
To: qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
It makes no sense to check for "any" blocker on bs, we are here only
because of the mechanical conversion from in_use to op_blockers. Remove
it now, and let the callers check specific operation types. Backup and
mirror already have it, add checker to stream and commit.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
---
blockdev.c | 8 ++++++++
blockjob.c | 2 +-
2 files changed, 9 insertions(+), 1 deletion(-)
diff --git a/blockdev.c b/blockdev.c
index 593925e..d68fd2b 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1846,6 +1846,10 @@ void qmp_block_stream(const char *device, bool has_base,
return;
}
+ if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_STREAM, errp)) {
+ return;
+ }
+
if (base) {
base_bs = bdrv_find_backing_image(bs, base);
if (base_bs == NULL) {
@@ -1886,6 +1890,10 @@ void qmp_block_commit(const char *device,
return;
}
+ if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT, errp)) {
+ return;
+ }
+
/* default top_bs is the active layer */
top_bs = bs;
diff --git a/blockjob.c b/blockjob.c
index f643a78..3e33051 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -41,7 +41,7 @@ void *block_job_create(const BlockJobDriver *driver, BlockDriverState *bs,
{
BlockJob *job;
- if (bs->job || !bdrv_op_blocker_is_empty(bs)) {
+ if (bs->job) {
error_set(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
return NULL;
}
--
1.9.0
^ permalink raw reply related [flat|nested] 36+ messages in thread
* [Qemu-devel] [PATCH v17 05/14] block: Add bdrv_set_backing_hd()
2014-03-10 7:25 [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
` (3 preceding siblings ...)
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 04/14] block: Move op_blocker check from block_job_create to its caller Fam Zheng
@ 2014-03-10 7:26 ` Fam Zheng
2014-04-07 0:01 ` Jeff Cody
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 06/14] block: Add backing_blocker in BlockDriverState Fam Zheng
` (9 subsequent siblings)
14 siblings, 1 reply; 36+ messages in thread
From: Fam Zheng @ 2014-03-10 7:26 UTC (permalink / raw)
To: qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
This is the common but non-trivial steps to assign or change the
backing_hd of BDS.
Signed-off-by: Fam Zheng <famz@redhat.com>
---
block.c | 39 +++++++++++++++++++++++++--------------
include/block/block.h | 1 +
2 files changed, 26 insertions(+), 14 deletions(-)
diff --git a/block.c b/block.c
index c79d5dc..64738dc 100644
--- a/block.c
+++ b/block.c
@@ -1047,6 +1047,23 @@ fail:
return ret;
}
+void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
+{
+
+ bs->backing_hd = backing_hd;
+ if (!backing_hd) {
+ bs->backing_file[0] = '\0';
+ bs->backing_format[0] = '\0';
+ goto out;
+ }
+ bs->open_flags &= ~BDRV_O_NO_BACKING;
+ pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename);
+ pstrcpy(bs->backing_format, sizeof(bs->backing_format),
+ backing_hd->drv ? backing_hd->drv->format_name : "");
+out:
+ bdrv_refresh_limits(bs);
+}
+
/*
* Opens the backing file for a BlockDriverState if not yet open
*
@@ -1060,6 +1077,7 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp)
char backing_filename[PATH_MAX];
int back_flags, ret;
BlockDriver *back_drv = NULL;
+ BlockDriverState *backing_hd;
Error *local_err = NULL;
if (bs->backing_hd != NULL) {
@@ -1083,6 +1101,8 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp)
sizeof(backing_filename));
}
+ backing_hd = bdrv_new("");
+
if (bs->backing_format[0] != '\0') {
back_drv = bdrv_find_format(bs->backing_format);
}
@@ -1091,23 +1111,19 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp)
back_flags = bs->open_flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT |
BDRV_O_COPY_ON_READ);
- assert(bs->backing_hd == NULL);
- ret = bdrv_open(&bs->backing_hd,
+ ret = bdrv_open(&backing_hd,
*backing_filename ? backing_filename : NULL, NULL, options,
back_flags, back_drv, &local_err);
if (ret < 0) {
- bs->backing_hd = NULL;
+ bdrv_unref(backing_hd);
+ backing_hd = NULL;
bs->open_flags |= BDRV_O_NO_BACKING;
error_setg(errp, "Could not open backing file: %s",
error_get_pretty(local_err));
error_free(local_err);
return ret;
}
-
- if (bs->backing_hd->file) {
- pstrcpy(bs->backing_file, sizeof(bs->backing_file),
- bs->backing_hd->file->filename);
- }
+ bdrv_set_backing_hd(bs, backing_hd);
/* Recalculate the BlockLimits with the backing file */
bdrv_refresh_limits(bs);
@@ -1944,12 +1960,7 @@ void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top)
/* The contents of 'tmp' will become bs_top, as we are
* swapping bs_new and bs_top contents. */
- bs_top->backing_hd = bs_new;
- bs_top->open_flags &= ~BDRV_O_NO_BACKING;
- pstrcpy(bs_top->backing_file, sizeof(bs_top->backing_file),
- bs_new->filename);
- pstrcpy(bs_top->backing_format, sizeof(bs_top->backing_format),
- bs_new->drv ? bs_new->drv->format_name : "");
+ bdrv_set_backing_hd(bs_top, bs_new);
}
static void bdrv_delete(BlockDriverState *bs)
diff --git a/include/block/block.h b/include/block/block.h
index a46f70a..ee1582d 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -208,6 +208,7 @@ int bdrv_parse_discard_flags(const char *mode, int *flags);
int bdrv_open_image(BlockDriverState **pbs, const char *filename,
QDict *options, const char *bdref_key, int flags,
bool allow_none, Error **errp);
+void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd);
int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp);
int bdrv_open(BlockDriverState **pbs, const char *filename,
const char *reference, QDict *options, int flags,
--
1.9.0
^ permalink raw reply related [flat|nested] 36+ messages in thread
* [Qemu-devel] [PATCH v17 06/14] block: Add backing_blocker in BlockDriverState
2014-03-10 7:25 [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
` (4 preceding siblings ...)
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 05/14] block: Add bdrv_set_backing_hd() Fam Zheng
@ 2014-03-10 7:26 ` Fam Zheng
2014-04-07 0:31 ` Jeff Cody
2014-04-09 18:29 ` Jeff Cody
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 07/14] block: Parse "backing" option to reference existing BDS Fam Zheng
` (8 subsequent siblings)
14 siblings, 2 replies; 36+ messages in thread
From: Fam Zheng @ 2014-03-10 7:26 UTC (permalink / raw)
To: qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
This makes use of op_blocker and blocks all the operations except for
commit target, on each BlockDriverState->backing_hd.
The asserts for op_blocker in bdrv_swap are removed because with this
change, the target of block commit has at least the backing blocker of
its child, so the assertion is not true. Callers should do their check.
Signed-off-by: Fam Zheng <famz@redhat.com>
---
block.c | 24 ++++++++++++++++++++----
block/mirror.c | 1 +
include/block/block_int.h | 3 +++
3 files changed, 24 insertions(+), 4 deletions(-)
diff --git a/block.c b/block.c
index 64738dc..95247c8 100644
--- a/block.c
+++ b/block.c
@@ -1050,16 +1050,33 @@ fail:
void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
{
+ if (bs->backing_hd) {
+ assert(error_is_set(&bs->backing_blocker));
+ bdrv_op_unblock_all(bs->backing_hd, bs->backing_blocker);
+ } else if (backing_hd) {
+ error_setg(&bs->backing_blocker,
+ "device is used as backing hd of '%s'",
+ bs->device_name);
+ }
+
bs->backing_hd = backing_hd;
if (!backing_hd) {
bs->backing_file[0] = '\0';
bs->backing_format[0] = '\0';
+ if (error_is_set(&bs->backing_blocker)) {
+ error_free(bs->backing_blocker);
+ }
goto out;
}
bs->open_flags &= ~BDRV_O_NO_BACKING;
pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename);
pstrcpy(bs->backing_format, sizeof(bs->backing_format),
backing_hd->drv ? backing_hd->drv->format_name : "");
+
+ bdrv_op_block_all(bs->backing_hd, bs->backing_blocker);
+ /* Otherwise we won't be able to commit due to check in bdrv_commit */
+ bdrv_op_unblock(bs->backing_hd, BLOCK_OP_TYPE_COMMIT,
+ bs->backing_blocker);
out:
bdrv_refresh_limits(bs);
}
@@ -1699,8 +1716,9 @@ void bdrv_close(BlockDriverState *bs)
if (bs->drv) {
if (bs->backing_hd) {
- bdrv_unref(bs->backing_hd);
- bs->backing_hd = NULL;
+ BlockDriverState *backing_hd = bs->backing_hd;
+ bdrv_set_backing_hd(bs, NULL);
+ bdrv_unref(backing_hd);
}
bs->drv->bdrv_close(bs);
g_free(bs->opaque);
@@ -1908,7 +1926,6 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
assert(QLIST_EMPTY(&bs_new->dirty_bitmaps));
assert(bs_new->job == NULL);
assert(bs_new->dev == NULL);
- assert(bdrv_op_blocker_is_empty(bs_new));
assert(bs_new->io_limits_enabled == false);
assert(!throttle_have_timer(&bs_new->throttle_state));
@@ -1927,7 +1944,6 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
/* Check a few fields that should remain attached to the device */
assert(bs_new->dev == NULL);
assert(bs_new->job == NULL);
- assert(bdrv_op_blocker_is_empty(bs_new));
assert(bs_new->io_limits_enabled == false);
assert(!throttle_have_timer(&bs_new->throttle_state));
diff --git a/block/mirror.c b/block/mirror.c
index dd5ee05..6dc84e8 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -487,6 +487,7 @@ immediate_exit:
* trigger the unref from the top one */
BlockDriverState *p = s->base->backing_hd;
s->base->backing_hd = NULL;
+ bdrv_op_unblock_all(p, s->base->backing_blocker);
bdrv_unref(p);
}
}
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 1d3f76f..1f4f78b 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -369,6 +369,9 @@ struct BlockDriverState {
BlockJob *job;
QDict *options;
+
+ /* The error object in use for blocking operations on backing_hd */
+ Error *backing_blocker;
};
int get_tmp_filename(char *filename, int size);
--
1.9.0
^ permalink raw reply related [flat|nested] 36+ messages in thread
* [Qemu-devel] [PATCH v17 07/14] block: Parse "backing" option to reference existing BDS
2014-03-10 7:25 [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
` (5 preceding siblings ...)
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 06/14] block: Add backing_blocker in BlockDriverState Fam Zheng
@ 2014-03-10 7:26 ` Fam Zheng
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 08/14] block: Support dropping active in bdrv_drop_intermediate Fam Zheng
` (7 subsequent siblings)
14 siblings, 0 replies; 36+ messages in thread
From: Fam Zheng @ 2014-03-10 7:26 UTC (permalink / raw)
To: qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
Now it's safe to allow reference for backing_hd in the interface.
Signed-off-by: Fam Zheng <famz@redhat.com>
---
block.c | 27 +++++++++++++++++++++++++--
1 file changed, 25 insertions(+), 2 deletions(-)
diff --git a/block.c b/block.c
index 95247c8..05f7766 100644
--- a/block.c
+++ b/block.c
@@ -1401,12 +1401,35 @@ int bdrv_open(BlockDriverState **pbs, const char *filename,
/* If there is a backing file, use it */
if ((flags & BDRV_O_NO_BACKING) == 0) {
QDict *backing_options;
+ const char *backing_name;
+ BlockDriverState *backing_hd;
+ backing_name = qdict_get_try_str(options, "backing");
qdict_extract_subqdict(options, &backing_options, "backing.");
- ret = bdrv_open_backing_file(bs, backing_options, &local_err);
- if (ret < 0) {
+
+ if (backing_name && qdict_size(backing_options)) {
+ error_setg(&local_err,
+ "Option \"backing\" and \"backing.*\" cannot be "
+ "used together");
+ ret = -EINVAL;
goto close_and_fail;
}
+ if (backing_name) {
+ backing_hd = bdrv_find(backing_name);
+ if (!backing_hd) {
+ error_set(&local_err, QERR_DEVICE_NOT_FOUND, backing_name);
+ ret = -ENOENT;
+ goto close_and_fail;
+ }
+ qdict_del(options, "backing");
+ bdrv_set_backing_hd(bs, backing_hd);
+ bdrv_ref(backing_hd);
+ } else {
+ ret = bdrv_open_backing_file(bs, backing_options, &local_err);
+ if (ret < 0) {
+ goto close_and_fail;
+ }
+ }
}
done:
--
1.9.0
^ permalink raw reply related [flat|nested] 36+ messages in thread
* [Qemu-devel] [PATCH v17 08/14] block: Support dropping active in bdrv_drop_intermediate
2014-03-10 7:25 [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
` (6 preceding siblings ...)
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 07/14] block: Parse "backing" option to reference existing BDS Fam Zheng
@ 2014-03-10 7:26 ` Fam Zheng
2014-04-07 18:47 ` Jeff Cody
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 09/14] stream: Use bdrv_drop_intermediate and drop close_unused_images Fam Zheng
` (6 subsequent siblings)
14 siblings, 1 reply; 36+ messages in thread
From: Fam Zheng @ 2014-03-10 7:26 UTC (permalink / raw)
To: qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
Dropping intermediate could be useful both for commit and stream, and
BDS refcnt plus bdrv_swap could do most of the job nicely. It also needs
to work with op blockers.
Signed-off-by: Fam Zheng <famz@redhat.com>
---
block.c | 139 ++++++++++++++++++++++++++++-----------------------------
block/commit.c | 2 +-
2 files changed, 70 insertions(+), 71 deletions(-)
diff --git a/block.c b/block.c
index 05f7766..0af7c62 100644
--- a/block.c
+++ b/block.c
@@ -2503,115 +2503,114 @@ BlockDriverState *bdrv_find_overlay(BlockDriverState *active,
return overlay;
}
-typedef struct BlkIntermediateStates {
- BlockDriverState *bs;
- QSIMPLEQ_ENTRY(BlkIntermediateStates) entry;
-} BlkIntermediateStates;
-
-
/*
- * Drops images above 'base' up to and including 'top', and sets the image
- * above 'top' to have base as its backing file.
+ * Drops images above 'base' up to and including 'top', and sets new 'base' as
+ * backing_hd of top's overlay (the image orignally has 'top' as backing file).
+ * top's overlay may be NULL if 'top' is active, no such update needed.
+ * Requires that the top's overlay to 'top' is opened r/w.
+ *
+ * 1) This will convert the following chain:
+ *
+ * ... <- base <- ... <- top <- overlay <-... <- active
*
- * Requires that the overlay to 'top' is opened r/w, so that the backing file
- * information in 'bs' can be properly updated.
+ * to
+ *
+ * ... <- base <- overlay <- active
+ *
+ * 2) It is allowed for bottom==base, in which case it converts:
*
- * E.g., this will convert the following chain:
- * bottom <- base <- intermediate <- top <- active
+ * base <- ... <- top <- overlay <- ... <- active
*
* to
*
- * bottom <- base <- active
+ * base <- overlay <- active
*
- * It is allowed for bottom==base, in which case it converts:
+ * 2) It also allows active==top, in which case it converts:
*
- * base <- intermediate <- top <- active
+ * ... <- base <- ... <- top (active)
*
* to
*
- * base <- active
+ * ... <- base == active == top
+ *
+ * i.e. only base and lower remains: *top == *base when return.
+ *
+ * 3) If base==NULL, it will drop all the BDS below overlay and set its
+ * backing_hd to NULL. I.e.:
*
- * Error conditions:
- * if active == top, that is considered an error
+ * base(NULL) <- ... <- overlay <- ... <- active
+ *
+ * to
+ *
+ * overlay <- ... <- active
*
*/
int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top,
BlockDriverState *base)
{
- BlockDriverState *intermediate;
- BlockDriverState *base_bs = NULL;
- BlockDriverState *new_top_bs = NULL;
- BlkIntermediateStates *intermediate_state, *next;
- int ret = -EIO;
-
- QSIMPLEQ_HEAD(states_to_delete, BlkIntermediateStates) states_to_delete;
- QSIMPLEQ_INIT(&states_to_delete);
+ BlockDriverState *drop_start, *overlay, *bs;
+ int ret = -EINVAL;
- if (!top->drv || !base->drv) {
+ assert(active);
+ assert(top);
+ /* Verify that top is in backing chain of active */
+ bs = active;
+ while (bs && bs != top) {
+ bs = bs->backing_hd;
+ }
+ if (!bs) {
goto exit;
}
+ /* Verify that base is in backing chain of top */
+ if (base) {
+ while (bs && bs != base) {
+ bs = bs->backing_hd;
+ }
+ if (bs != base) {
+ goto exit;
+ }
+ }
- new_top_bs = bdrv_find_overlay(active, top);
-
- if (new_top_bs == NULL) {
- /* we could not find the image above 'top', this is an error */
+ if (!top->drv || (base && !base->drv)) {
goto exit;
}
-
- /* special case of new_top_bs->backing_hd already pointing to base - nothing
- * to do, no intermediate images */
- if (new_top_bs->backing_hd == base) {
+ if (top == base) {
+ ret = 0;
+ goto exit;
+ } else if (top == active) {
+ assert(base);
+ drop_start = active->backing_hd;
+ bdrv_swap(active, base);
+ base->backing_hd = NULL;
+ bdrv_unref(drop_start);
ret = 0;
goto exit;
}
- intermediate = top;
-
- /* now we will go down through the list, and add each BDS we find
- * into our deletion queue, until we hit the 'base'
- */
- while (intermediate) {
- intermediate_state = g_malloc0(sizeof(BlkIntermediateStates));
- intermediate_state->bs = intermediate;
- QSIMPLEQ_INSERT_TAIL(&states_to_delete, intermediate_state, entry);
-
- if (intermediate->backing_hd == base) {
- base_bs = intermediate->backing_hd;
- break;
- }
- intermediate = intermediate->backing_hd;
- }
- if (base_bs == NULL) {
- /* something went wrong, we did not end at the base. safely
- * unravel everything, and exit with error */
+ overlay = bdrv_find_overlay(active, top);
+ if (!overlay) {
goto exit;
}
-
- /* success - we can delete the intermediate states, and link top->base */
- ret = bdrv_change_backing_file(new_top_bs, base_bs->filename,
- base_bs->drv ? base_bs->drv->format_name : "");
+ ret = bdrv_change_backing_file(overlay,
+ base ? base->filename : NULL,
+ base ? base->drv->format_name : NULL);
if (ret) {
goto exit;
}
- new_top_bs->backing_hd = base_bs;
- bdrv_refresh_limits(new_top_bs);
-
- QSIMPLEQ_FOREACH_SAFE(intermediate_state, &states_to_delete, entry, next) {
- /* so that bdrv_close() does not recursively close the chain */
- intermediate_state->bs->backing_hd = NULL;
- bdrv_unref(intermediate_state->bs);
+ bs = overlay->backing_hd;
+ bdrv_set_backing_hd(overlay, base);
+ if (base) {
+ bdrv_ref(base);
+ }
+ if (bs) {
+ bdrv_unref(bs);
}
ret = 0;
-
exit:
- QSIMPLEQ_FOREACH_SAFE(intermediate_state, &states_to_delete, entry, next) {
- g_free(intermediate_state);
- }
return ret;
}
-
static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset,
size_t size)
{
diff --git a/block/commit.c b/block/commit.c
index acec4ac..ac598d6 100644
--- a/block/commit.c
+++ b/block/commit.c
@@ -73,6 +73,7 @@ static void coroutine_fn commit_run(void *opaque)
int bytes_written = 0;
int64_t base_len;
+ overlay_bs = bdrv_find_overlay(active, top);
ret = s->common.len = bdrv_getlength(top);
@@ -154,7 +155,6 @@ exit_restore_reopen:
if (s->base_flags != bdrv_get_flags(base)) {
bdrv_reopen(base, s->base_flags, NULL);
}
- overlay_bs = bdrv_find_overlay(active, top);
if (overlay_bs && s->orig_overlay_flags != bdrv_get_flags(overlay_bs)) {
bdrv_reopen(overlay_bs, s->orig_overlay_flags, NULL);
}
--
1.9.0
^ permalink raw reply related [flat|nested] 36+ messages in thread
* [Qemu-devel] [PATCH v17 09/14] stream: Use bdrv_drop_intermediate and drop close_unused_images
2014-03-10 7:25 [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
` (7 preceding siblings ...)
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 08/14] block: Support dropping active in bdrv_drop_intermediate Fam Zheng
@ 2014-03-10 7:26 ` Fam Zheng
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 10/14] qmp: Add command 'blockdev-backup' Fam Zheng
` (5 subsequent siblings)
14 siblings, 0 replies; 36+ messages in thread
From: Fam Zheng @ 2014-03-10 7:26 UTC (permalink / raw)
To: qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
This reuses the new bdrv_drop_intermediate.
Signed-off-by: Fam Zheng <famz@redhat.com>
---
block/stream.c | 42 +-----------------------------------------
1 file changed, 1 insertion(+), 41 deletions(-)
diff --git a/block/stream.c b/block/stream.c
index dd0b4ac..1b348a2 100644
--- a/block/stream.c
+++ b/block/stream.c
@@ -32,7 +32,6 @@ typedef struct StreamBlockJob {
RateLimit limit;
BlockDriverState *base;
BlockdevOnError on_error;
- char backing_file_id[1024];
} StreamBlockJob;
static int coroutine_fn stream_populate(BlockDriverState *bs,
@@ -51,34 +50,6 @@ static int coroutine_fn stream_populate(BlockDriverState *bs,
return bdrv_co_copy_on_readv(bs, sector_num, nb_sectors, &qiov);
}
-static void close_unused_images(BlockDriverState *top, BlockDriverState *base,
- const char *base_id)
-{
- BlockDriverState *intermediate;
- intermediate = top->backing_hd;
-
- /* Must assign before bdrv_delete() to prevent traversing dangling pointer
- * while we delete backing image instances.
- */
- top->backing_hd = base;
-
- while (intermediate) {
- BlockDriverState *unused;
-
- /* reached base */
- if (intermediate == base) {
- break;
- }
-
- unused = intermediate;
- intermediate = intermediate->backing_hd;
- unused->backing_hd = NULL;
- bdrv_unref(unused);
- }
-
- bdrv_refresh_limits(top);
-}
-
static void coroutine_fn stream_run(void *opaque)
{
StreamBlockJob *s = opaque;
@@ -184,15 +155,7 @@ wait:
ret = error;
if (!block_job_is_cancelled(&s->common) && sector_num == end && ret == 0) {
- const char *base_id = NULL, *base_fmt = NULL;
- if (base) {
- base_id = s->backing_file_id;
- if (base->drv) {
- base_fmt = base->drv->format_name;
- }
- }
- ret = bdrv_change_backing_file(bs, base_id, base_fmt);
- close_unused_images(bs, base, base_id);
+ ret = bdrv_drop_intermediate(bs, bs->backing_hd, base);
}
qemu_vfree(buf);
@@ -237,9 +200,6 @@ void stream_start(BlockDriverState *bs, BlockDriverState *base,
}
s->base = base;
- if (base_id) {
- pstrcpy(s->backing_file_id, sizeof(s->backing_file_id), base_id);
- }
s->on_error = on_error;
s->common.co = qemu_coroutine_create(stream_run);
--
1.9.0
^ permalink raw reply related [flat|nested] 36+ messages in thread
* [Qemu-devel] [PATCH v17 10/14] qmp: Add command 'blockdev-backup'
2014-03-10 7:25 [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
` (8 preceding siblings ...)
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 09/14] stream: Use bdrv_drop_intermediate and drop close_unused_images Fam Zheng
@ 2014-03-10 7:26 ` Fam Zheng
2014-04-07 21:07 ` Eric Blake
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 11/14] block: Allow backup on referenced named BlockDriverState Fam Zheng
` (4 subsequent siblings)
14 siblings, 1 reply; 36+ messages in thread
From: Fam Zheng @ 2014-03-10 7:26 UTC (permalink / raw)
To: qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
Similar to drive-backup, but this command uses a device id as target
instead of creating/opening an image file.
Also add blocker on target bs, since the target is also a named device
now.
Add check and report error for bs == target which became possible but is
an illegal case with introduction of blockdev-backup.
Signed-off-by: Fam Zheng <famz@redhat.com>
---
block/backup.c | 26 ++++++++++++++++++++++++++
blockdev.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
qapi-schema.json | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
qmp-commands.hx | 44 ++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 166 insertions(+)
diff --git a/block/backup.c b/block/backup.c
index 15a2e55..ea46340 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -344,6 +344,7 @@ static void coroutine_fn backup_run(void *opaque)
hbitmap_free(job->bitmap);
bdrv_iostatus_disable(target);
+ bdrv_op_unblock_all(target, job->common.blocker);
bdrv_unref(target);
block_job_completed(&job->common, ret);
@@ -362,6 +363,11 @@ void backup_start(BlockDriverState *bs, BlockDriverState *target,
assert(target);
assert(cb);
+ if (bs == target) {
+ error_setg(errp, "Source and target cannot be the same");
+ return;
+ }
+
if ((on_source_error == BLOCKDEV_ON_ERROR_STOP ||
on_source_error == BLOCKDEV_ON_ERROR_ENOSPC) &&
!bdrv_iostatus_is_enabled(bs)) {
@@ -369,6 +375,24 @@ void backup_start(BlockDriverState *bs, BlockDriverState *target,
return;
}
+ if (!bdrv_is_inserted(bs)) {
+ error_set(errp, QERR_DEVICE_HAS_NO_MEDIUM, bs->device_name);
+ return;
+ }
+
+ if (!bdrv_is_inserted(target)) {
+ error_set(errp, QERR_DEVICE_HAS_NO_MEDIUM, target->device_name);
+ return;
+ }
+
+ if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
+ return;
+ }
+
+ if (bdrv_op_is_blocked(target, BLOCK_OP_TYPE_BACKUP_TARGET, errp)) {
+ return;
+ }
+
len = bdrv_getlength(bs);
if (len < 0) {
error_setg_errno(errp, -len, "unable to get length for '%s'",
@@ -382,6 +406,8 @@ void backup_start(BlockDriverState *bs, BlockDriverState *target,
return;
}
+ bdrv_op_block_all(target, job->common.blocker);
+
job->on_source_error = on_source_error;
job->on_target_error = on_target_error;
job->target = target;
diff --git a/blockdev.c b/blockdev.c
index d68fd2b..f241455 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1969,6 +1969,8 @@ void qmp_drive_backup(const char *device, const char *target,
return;
}
+ /* Although backup_run has this check too, we need to use bs->drv below, so
+ * do an early check redundantly. */
if (!bdrv_is_inserted(bs)) {
error_set(errp, QERR_DEVICE_HAS_NO_MEDIUM, device);
return;
@@ -1985,6 +1987,7 @@ void qmp_drive_backup(const char *device, const char *target,
}
}
+ /* Early check to avoid creating target */
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
return;
}
@@ -2047,6 +2050,50 @@ BlockDeviceInfoList *qmp_query_named_block_nodes(Error **errp)
return bdrv_named_nodes_list();
}
+void qmp_blockdev_backup(const char *device, const char *target,
+ enum MirrorSyncMode sync,
+ bool has_speed, int64_t speed,
+ bool has_on_source_error,
+ BlockdevOnError on_source_error,
+ bool has_on_target_error,
+ BlockdevOnError on_target_error,
+ Error **errp)
+{
+ BlockDriverState *bs;
+ BlockDriverState *target_bs;
+ Error *local_err = NULL;
+
+ if (!has_speed) {
+ speed = 0;
+ }
+ if (!has_on_source_error) {
+ on_source_error = BLOCKDEV_ON_ERROR_REPORT;
+ }
+ if (!has_on_target_error) {
+ on_target_error = BLOCKDEV_ON_ERROR_REPORT;
+ }
+
+ bs = bdrv_find(device);
+ if (!bs) {
+ error_set(errp, QERR_DEVICE_NOT_FOUND, device);
+ return;
+ }
+
+ target_bs = bdrv_find(target);
+ if (!target_bs) {
+ error_set(errp, QERR_DEVICE_NOT_FOUND, target);
+ return;
+ }
+
+ bdrv_ref(target_bs);
+ backup_start(bs, target_bs, speed, sync, on_source_error, on_target_error,
+ block_job_cb, bs, &local_err);
+ if (local_err != NULL) {
+ bdrv_unref(target_bs);
+ error_propagate(errp, local_err);
+ }
+}
+
#define DEFAULT_MIRROR_BUF_SIZE (10 << 20)
void qmp_drive_mirror(const char *device, const char *target,
diff --git a/qapi-schema.json b/qapi-schema.json
index 6c381b7..acff31a 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -1919,6 +1919,40 @@
'*on-target-error': 'BlockdevOnError' } }
##
+# @BlockdevBackup
+#
+# @device: the name of the device which should be copied.
+#
+# @target: the name of the backup target device.
+#
+# @sync: what parts of the disk image should be copied to the destination
+# (all the disk, only the sectors allocated in the topmost image, or
+# only new I/O).
+#
+# @speed: #optional the maximum speed, in bytes per second.
+#
+# @on-source-error: #optional the action to take on an error on the source,
+# default 'report'. 'stop' and 'enospc' can only be used
+# if the block device supports io-status (see BlockInfo).
+#
+# @on-target-error: #optional the action to take on an error on the target,
+# default 'report' (no limitations, since this applies to
+# a different block device than @device).
+#
+# Note that @on-source-error and @on-target-error only affect background I/O.
+# If an error occurs during a guest write request, the device's rerror/werror
+# actions will be used.
+#
+# Since: 2.0
+##
+{ 'type': 'BlockdevBackup',
+ 'data': { 'device': 'str', 'target': 'str',
+ 'sync': 'MirrorSyncMode',
+ '*speed': 'int',
+ '*on-source-error': 'BlockdevOnError',
+ '*on-target-error': 'BlockdevOnError' } }
+
+##
# @Abort
#
# This action can be used to test transaction failure.
@@ -2127,6 +2161,21 @@
{ 'command': 'query-named-block-nodes', 'returns': [ 'BlockDeviceInfo' ] }
##
+# @blockdev-backup
+#
+# Block device version for drive-backup command. Use existing device as target
+# of backup.
+#
+# For the arguments, see the documentation of BlockdevBackup.
+#
+# Returns: Nothing on success.
+# If @device or @target is not a valid block device, DeviceNotFound.
+#
+# Since 2.0
+##
+{ 'command': 'blockdev-backup', 'data': 'BlockdevBackup' }
+
+##
# @drive-mirror
#
# Start mirroring a block device's writes to a new destination.
diff --git a/qmp-commands.hx b/qmp-commands.hx
index d982cd6..dd336f7 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -1077,6 +1077,50 @@ Example:
"sync": "full",
"target": "backup.img" } }
<- { "return": {} }
+
+EQMP
+
+ {
+ .name = "blockdev-backup",
+ .args_type = "sync:s,device:B,target:B,speed:i?,"
+ "on-source-error:s?,on-target-error:s?",
+ .mhandler.cmd_new = qmp_marshal_input_blockdev_backup,
+ },
+
+SQMP
+blockdev-backup
+------------
+
+The device version of drive-backup: this command takes a existing named device
+as backup target.
+
+Arguments:
+
+- "device": the name of the device which should be copied.
+ (json-string)
+- "target": the target of the new image. If the file exists, or if it is a
+ device, the existing file/device will be used as the new
+ destination. If it does not exist, a new file will be created.
+ (json-string)
+- "sync": what parts of the disk image should be copied to the destination;
+ possibilities include "full" for all the disk, "top" for only the
+ sectors allocated in the topmost image, or "none" to only replicate
+ new I/O (MirrorSyncMode).
+- "speed": the maximum speed, in bytes per second (json-int, optional)
+- "on-source-error": the action to take on an error on the source, default
+ 'report'. 'stop' and 'enospc' can only be used
+ if the block device supports io-status.
+ (BlockdevOnError, optional)
+- "on-target-error": the action to take on an error on the target, default
+ 'report' (no limitations, since this applies to
+ a different block device than device).
+ (BlockdevOnError, optional)
+
+Example:
+-> { "execute": "blockdev-backup", "arguments": { "device": "src-id",
+ "target": "tgt-id" } }
+<- { "return": {} }
+
EQMP
{
--
1.9.0
^ permalink raw reply related [flat|nested] 36+ messages in thread
* [Qemu-devel] [PATCH v17 11/14] block: Allow backup on referenced named BlockDriverState
2014-03-10 7:25 [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
` (9 preceding siblings ...)
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 10/14] qmp: Add command 'blockdev-backup' Fam Zheng
@ 2014-03-10 7:26 ` Fam Zheng
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 12/14] block: Add blockdev-backup to transaction Fam Zheng
` (3 subsequent siblings)
14 siblings, 0 replies; 36+ messages in thread
From: Fam Zheng @ 2014-03-10 7:26 UTC (permalink / raw)
To: qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
Drive backup is a read only operation on source bs. We want to allow
this specific case to enable image-fleecing. Note that when
image-fleecing job starts, the job still add its blocker to source bs,
and any other operation on it will be blocked by that.
Signed-off-by: Fam Zheng <famz@redhat.com>
---
block.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/block.c b/block.c
index 0af7c62..9f2fe85 100644
--- a/block.c
+++ b/block.c
@@ -1077,6 +1077,8 @@ void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
/* Otherwise we won't be able to commit due to check in bdrv_commit */
bdrv_op_unblock(bs->backing_hd, BLOCK_OP_TYPE_COMMIT,
bs->backing_blocker);
+ bdrv_op_unblock(bs->backing_hd, BLOCK_OP_TYPE_BACKUP_SOURCE,
+ bs->backing_blocker);
out:
bdrv_refresh_limits(bs);
}
--
1.9.0
^ permalink raw reply related [flat|nested] 36+ messages in thread
* [Qemu-devel] [PATCH v17 12/14] block: Add blockdev-backup to transaction
2014-03-10 7:25 [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
` (10 preceding siblings ...)
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 11/14] block: Allow backup on referenced named BlockDriverState Fam Zheng
@ 2014-03-10 7:26 ` Fam Zheng
2014-04-07 21:11 ` Eric Blake
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 13/14] qemu-iotests: Test blockdev-backup in 055 Fam Zheng
` (2 subsequent siblings)
14 siblings, 1 reply; 36+ messages in thread
From: Fam Zheng @ 2014-03-10 7:26 UTC (permalink / raw)
To: qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
Signed-off-by: Fam Zheng <famz@redhat.com>
---
blockdev.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
qapi-schema.json | 1 +
2 files changed, 49 insertions(+)
diff --git a/blockdev.c b/blockdev.c
index f241455..8a6ae0a 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1409,6 +1409,49 @@ static void drive_backup_abort(BlkTransactionState *common)
}
}
+typedef struct BlockdevBackupState {
+ BlkTransactionState common;
+ BlockDriverState *bs;
+ BlockJob *job;
+} BlockdevBackupState;
+
+static void blockdev_backup_prepare(BlkTransactionState *common, Error **errp)
+{
+ BlockdevBackupState *state = DO_UPCAST(BlockdevBackupState, common, common);
+ BlockdevBackup *backup;
+ Error *local_err = NULL;
+
+ assert(common->action->kind == TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP);
+ backup = common->action->blockdev_backup;
+
+ qmp_blockdev_backup(backup->device, backup->target,
+ backup->sync,
+ backup->has_speed, backup->speed,
+ backup->has_on_source_error, backup->on_source_error,
+ backup->has_on_target_error, backup->on_target_error,
+ &local_err);
+ if (error_is_set(&local_err)) {
+ error_propagate(errp, local_err);
+ state->bs = NULL;
+ state->job = NULL;
+ return;
+ }
+
+ state->bs = bdrv_find(backup->device);
+ state->job = state->bs->job;
+}
+
+static void blockdev_backup_abort(BlkTransactionState *common)
+{
+ BlockdevBackupState *state = DO_UPCAST(BlockdevBackupState, common, common);
+ BlockDriverState *bs = state->bs;
+
+ /* Only cancel if it's the job we started */
+ if (bs && bs->job && bs->job == state->job) {
+ block_job_cancel_sync(bs->job);
+ }
+}
+
static void abort_prepare(BlkTransactionState *common, Error **errp)
{
error_setg(errp, "Transaction aborted using Abort action");
@@ -1431,6 +1474,11 @@ static const BdrvActionOps actions[] = {
.prepare = drive_backup_prepare,
.abort = drive_backup_abort,
},
+ [TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP] = {
+ .instance_size = sizeof(BlockdevBackupState),
+ .prepare = blockdev_backup_prepare,
+ .abort = blockdev_backup_abort,
+ },
[TRANSACTION_ACTION_KIND_ABORT] = {
.instance_size = sizeof(BlkTransactionState),
.prepare = abort_prepare,
diff --git a/qapi-schema.json b/qapi-schema.json
index acff31a..6476d4a 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -1972,6 +1972,7 @@
'data': {
'blockdev-snapshot-sync': 'BlockdevSnapshot',
'drive-backup': 'DriveBackup',
+ 'blockdev-backup': 'BlockdevBackup',
'abort': 'Abort',
'blockdev-snapshot-internal-sync': 'BlockdevSnapshotInternal'
} }
--
1.9.0
^ permalink raw reply related [flat|nested] 36+ messages in thread
* [Qemu-devel] [PATCH v17 13/14] qemu-iotests: Test blockdev-backup in 055
2014-03-10 7:25 [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
` (11 preceding siblings ...)
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 12/14] block: Add blockdev-backup to transaction Fam Zheng
@ 2014-03-10 7:26 ` Fam Zheng
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 14/14] qemu-iotests: Image fleecing test case 083 Fam Zheng
2014-04-02 6:01 ` [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
14 siblings, 0 replies; 36+ messages in thread
From: Fam Zheng @ 2014-03-10 7:26 UTC (permalink / raw)
To: qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
This applies cases on drive-backup on blockdev-backup, except cases with
target format and mode.
Also add a case to check source == target.
Signed-off-by: Fam Zheng <famz@redhat.com>
---
tests/qemu-iotests/055 | 275 ++++++++++++++++++++++++++++++++++++++-------
tests/qemu-iotests/055.out | 4 +-
2 files changed, 235 insertions(+), 44 deletions(-)
diff --git a/tests/qemu-iotests/055 b/tests/qemu-iotests/055
index 451b67d..1fab088 100755
--- a/tests/qemu-iotests/055
+++ b/tests/qemu-iotests/055
@@ -1,6 +1,6 @@
#!/usr/bin/env python
#
-# Tests for drive-backup
+# Tests for drive-backup and blockdev-backup
#
# Copyright (C) 2013 Red Hat, Inc.
#
@@ -27,6 +27,7 @@ from iotests import qemu_img, qemu_io
test_img = os.path.join(iotests.test_dir, 'test.img')
target_img = os.path.join(iotests.test_dir, 'target.img')
+blockdev_target_img = os.path.join(iotests.test_dir, 'blockdev-target.img')
class TestSingleDrive(iotests.QMPTestCase):
image_len = 64 * 1024 * 1024 # MB
@@ -38,34 +39,48 @@ class TestSingleDrive(iotests.QMPTestCase):
qemu_io('-c', 'write -P0xd5 1M 32k', test_img)
qemu_io('-c', 'write -P0xdc 32M 124k', test_img)
qemu_io('-c', 'write -P0xdc 67043328 64k', test_img)
+ qemu_img('create', '-f', iotests.imgfmt, blockdev_target_img, str(TestSingleDrive.image_len))
- self.vm = iotests.VM().add_drive(test_img)
+ self.vm = iotests.VM().add_drive(test_img).add_drive(blockdev_target_img)
self.vm.launch()
def tearDown(self):
self.vm.shutdown()
os.remove(test_img)
+ os.remove(blockdev_target_img)
try:
os.remove(target_img)
except OSError:
pass
- def test_cancel(self):
+ def do_test_cancel(self, test_drive_backup):
self.assert_no_active_block_jobs()
- result = self.vm.qmp('drive-backup', device='drive0',
- target=target_img, sync='full')
+ if test_drive_backup:
+ result = self.vm.qmp('drive-backup', device='drive0',
+ target=target_img, sync='full')
+ else:
+ result = self.vm.qmp('blockdev-backup', device='drive0',
+ target='drive1', sync='full')
self.assert_qmp(result, 'return', {})
event = self.cancel_and_wait()
self.assert_qmp(event, 'data/type', 'backup')
- def test_pause(self):
+ def test_cancel(self):
+ self.do_test_cancel(True)
+ self.do_test_cancel(False)
+
+ def do_test_pause(self, test_drive_backup):
self.assert_no_active_block_jobs()
self.vm.pause_drive('drive0')
- result = self.vm.qmp('drive-backup', device='drive0',
- target=target_img, sync='full')
+ if test_drive_backup:
+ result = self.vm.qmp('drive-backup', device='drive0',
+ target=target_img, sync='full')
+ else:
+ result = self.vm.qmp('blockdev-backup', device='drive0',
+ target='drive1', sync='full')
self.assert_qmp(result, 'return', {})
result = self.vm.qmp('block-job-pause', device='drive0')
@@ -86,14 +101,28 @@ class TestSingleDrive(iotests.QMPTestCase):
self.wait_until_completed()
self.vm.shutdown()
- self.assertTrue(iotests.compare_images(test_img, target_img),
- 'target image does not match source after backup')
+ if test_drive_backup:
+ self.assertTrue(iotests.compare_images(test_img, target_img),
+ 'target image does not match source after backup')
+ else:
+ self.assertTrue(iotests.compare_images(test_img, blockdev_target_img),
+ 'target image does not match source after backup')
+
+ def test_pause_drive_backup(self):
+ self.do_test_pause(True)
+
+ def test_pause_blockdev_backup(self):
+ self.do_test_pause(False)
def test_medium_not_found(self):
result = self.vm.qmp('drive-backup', device='ide1-cd0',
target=target_img, sync='full')
self.assert_qmp(result, 'error/class', 'GenericError')
+ result = self.vm.qmp('blockdev-backup', device='ide1-cd0',
+ target='drive1', sync='full')
+ self.assert_qmp(result, 'error/class', 'GenericError')
+
def test_image_not_found(self):
result = self.vm.qmp('drive-backup', device='drive0',
target=target_img, sync='full', mode='existing')
@@ -110,26 +139,56 @@ class TestSingleDrive(iotests.QMPTestCase):
target=target_img, sync='full')
self.assert_qmp(result, 'error/class', 'DeviceNotFound')
+ result = self.vm.qmp('blockdev-backup', device='nonexistent',
+ target='drive0', sync='full')
+ self.assert_qmp(result, 'error/class', 'DeviceNotFound')
+
+ result = self.vm.qmp('blockdev-backup', device='drive0',
+ target='nonexistent', sync='full')
+ self.assert_qmp(result, 'error/class', 'DeviceNotFound')
+
+ result = self.vm.qmp('blockdev-backup', device='nonexistent',
+ target='nonexistent', sync='full')
+ self.assert_qmp(result, 'error/class', 'DeviceNotFound')
+
+ def test_target_is_source(self):
+ result = self.vm.qmp('blockdev-backup', device='drive0',
+ target='drive0', sync='full')
+ self.assert_qmp(result, 'error/class', 'GenericError')
+
class TestSetSpeed(iotests.QMPTestCase):
image_len = 80 * 1024 * 1024 # MB
def setUp(self):
qemu_img('create', '-f', iotests.imgfmt, test_img, str(TestSetSpeed.image_len))
qemu_io('-c', 'write -P1 0 512', test_img)
- self.vm = iotests.VM().add_drive(test_img)
+ qemu_img('create', '-f', iotests.imgfmt, blockdev_target_img, str(TestSingleDrive.image_len))
+
+ self.vm = iotests.VM().add_drive(test_img).add_drive(blockdev_target_img)
self.vm.launch()
def tearDown(self):
self.vm.shutdown()
os.remove(test_img)
- os.remove(target_img)
+ try:
+ os.remove(blockdev_target_img)
+ except OSError:
+ pass
+ try:
+ os.remove(target_img)
+ except OSError:
+ pass
- def test_set_speed(self):
+ def do_test_set_speed(self, test_drive_backup):
self.assert_no_active_block_jobs()
self.vm.pause_drive('drive0')
- result = self.vm.qmp('drive-backup', device='drive0',
- target=target_img, sync='full')
+ if test_drive_backup:
+ result = self.vm.qmp('drive-backup', device='drive0',
+ target=target_img, sync='full')
+ else:
+ result = self.vm.qmp('blockdev-backup', device='drive0',
+ target='drive1', sync='full')
self.assert_qmp(result, 'return', {})
# Default speed is 0
@@ -148,10 +207,14 @@ class TestSetSpeed(iotests.QMPTestCase):
event = self.cancel_and_wait(resume=True)
self.assert_qmp(event, 'data/type', 'backup')
- # Check setting speed in drive-backup works
+ # Check setting speed option works
self.vm.pause_drive('drive0')
- result = self.vm.qmp('drive-backup', device='drive0',
- target=target_img, sync='full', speed=4*1024*1024)
+ if test_drive_backup:
+ result = self.vm.qmp('drive-backup', device='drive0',
+ target=target_img, sync='full', speed=4*1024*1024)
+ else:
+ result = self.vm.qmp('blockdev-backup', device='drive0',
+ target='drive1', sync='full', speed=4*1024*1024)
self.assert_qmp(result, 'return', {})
result = self.vm.qmp('query-block-jobs')
@@ -161,18 +224,32 @@ class TestSetSpeed(iotests.QMPTestCase):
event = self.cancel_and_wait(resume=True)
self.assert_qmp(event, 'data/type', 'backup')
- def test_set_speed_invalid(self):
+ def test_set_speed_drive_backup(self):
+ self.do_test_set_speed(True)
+
+ def test_set_speed_blockdev_backup(self):
+ self.do_test_set_speed(False)
+
+ def do_test_set_speed_invalid(self, test_drive_backup):
self.assert_no_active_block_jobs()
- result = self.vm.qmp('drive-backup', device='drive0',
- target=target_img, sync='full', speed=-1)
+ if test_drive_backup:
+ result = self.vm.qmp('drive-backup', device='drive0',
+ target=target_img, sync='full', speed=-1)
+ else:
+ result = self.vm.qmp('blockdev-backup', device='drive0',
+ target='drive1', sync='full', speed=-1)
self.assert_qmp(result, 'error/class', 'GenericError')
self.assert_no_active_block_jobs()
self.vm.pause_drive('drive0')
- result = self.vm.qmp('drive-backup', device='drive0',
- target=target_img, sync='full')
+ if test_drive_backup:
+ result = self.vm.qmp('drive-backup', device='drive0',
+ target=target_img, sync='full')
+ else:
+ result = self.vm.qmp('blockdev-backup', device='drive0',
+ target='drive1', sync='full')
self.assert_qmp(result, 'return', {})
result = self.vm.qmp('block-job-set-speed', device='drive0', speed=-1)
@@ -181,6 +258,12 @@ class TestSetSpeed(iotests.QMPTestCase):
event = self.cancel_and_wait(resume=True)
self.assert_qmp(event, 'data/type', 'backup')
+ def test_set_speed_invalid_drive_backup(self):
+ self.do_test_set_speed_invalid(True)
+
+ def test_set_speed_invalid_blockdev_backup(self):
+ self.do_test_set_speed_invalid(False)
+
class TestSingleTransaction(iotests.QMPTestCase):
image_len = 64 * 1024 * 1024 # MB
@@ -190,44 +273,71 @@ class TestSingleTransaction(iotests.QMPTestCase):
qemu_io('-c', 'write -P0xd5 1M 32k', test_img)
qemu_io('-c', 'write -P0xdc 32M 124k', test_img)
qemu_io('-c', 'write -P0xdc 67043328 64k', test_img)
+ qemu_img('create', '-f', iotests.imgfmt, blockdev_target_img, str(TestSingleDrive.image_len))
- self.vm = iotests.VM().add_drive(test_img)
+ self.vm = iotests.VM().add_drive(test_img).add_drive(blockdev_target_img)
self.vm.launch()
def tearDown(self):
self.vm.shutdown()
os.remove(test_img)
+ os.remove(blockdev_target_img)
try:
os.remove(target_img)
except OSError:
pass
- def test_cancel(self):
+ def do_test_cancel(self, test_drive_backup):
self.assert_no_active_block_jobs()
- result = self.vm.qmp('transaction', actions=[{
- 'type': 'drive-backup',
- 'data': { 'device': 'drive0',
- 'target': target_img,
- 'sync': 'full' },
- }
- ])
+ if test_drive_backup:
+ result = self.vm.qmp('transaction', actions=[{
+ 'type': 'drive-backup',
+ 'data': { 'device': 'drive0',
+ 'target': target_img,
+ 'sync': 'full' },
+ }
+ ])
+ else:
+ result = self.vm.qmp('transaction', actions=[{
+ 'type': 'blockdev-backup',
+ 'data': { 'device': 'drive0',
+ 'target': 'drive1',
+ 'sync': 'full' },
+ }
+ ])
+
self.assert_qmp(result, 'return', {})
event = self.cancel_and_wait()
self.assert_qmp(event, 'data/type', 'backup')
- def test_pause(self):
+ def test_cancel_drive_backup(self):
+ self.do_test_cancel(True)
+
+ def test_cancel_blockdev_backup(self):
+ self.do_test_cancel(False)
+
+ def do_test_pause(self, test_drive_backup):
self.assert_no_active_block_jobs()
self.vm.pause_drive('drive0')
- result = self.vm.qmp('transaction', actions=[{
- 'type': 'drive-backup',
- 'data': { 'device': 'drive0',
- 'target': target_img,
- 'sync': 'full' },
- }
- ])
+ if test_drive_backup:
+ result = self.vm.qmp('transaction', actions=[{
+ 'type': 'drive-backup',
+ 'data': { 'device': 'drive0',
+ 'target': target_img,
+ 'sync': 'full' },
+ }
+ ])
+ else:
+ result = self.vm.qmp('transaction', actions=[{
+ 'type': 'blockdev-backup',
+ 'data': { 'device': 'drive0',
+ 'target': 'drive1',
+ 'sync': 'full' },
+ }
+ ])
self.assert_qmp(result, 'return', {})
result = self.vm.qmp('block-job-pause', device='drive0')
@@ -248,8 +358,18 @@ class TestSingleTransaction(iotests.QMPTestCase):
self.wait_until_completed()
self.vm.shutdown()
- self.assertTrue(iotests.compare_images(test_img, target_img),
- 'target image does not match source after backup')
+ if test_drive_backup:
+ self.assertTrue(iotests.compare_images(test_img, target_img),
+ 'target image does not match source after backup')
+ else:
+ self.assertTrue(iotests.compare_images(test_img, blockdev_target_img),
+ 'target image does not match source after backup')
+
+ def test_pause_drive_backup(self):
+ self.do_test_pause(True)
+
+ def test_pause_blockdev_backup(self):
+ self.do_test_pause(False)
def test_medium_not_found(self):
result = self.vm.qmp('transaction', actions=[{
@@ -260,6 +380,14 @@ class TestSingleTransaction(iotests.QMPTestCase):
}
])
self.assert_qmp(result, 'error/class', 'GenericError')
+ result = self.vm.qmp('transaction', actions=[{
+ 'type': 'blockdev-backup',
+ 'data': { 'device': 'ide1-cd0',
+ 'target': 'drive1',
+ 'sync': 'full' },
+ }
+ ])
+ self.assert_qmp(result, 'error/class', 'GenericError')
def test_image_not_found(self):
result = self.vm.qmp('transaction', actions=[{
@@ -283,6 +411,43 @@ class TestSingleTransaction(iotests.QMPTestCase):
])
self.assert_qmp(result, 'error/class', 'DeviceNotFound')
+ result = self.vm.qmp('transaction', actions=[{
+ 'type': 'blockdev-backup',
+ 'data': { 'device': 'nonexistent',
+ 'target': 'drive1',
+ 'sync': 'full' },
+ }
+ ])
+ self.assert_qmp(result, 'error/class', 'DeviceNotFound')
+
+ result = self.vm.qmp('transaction', actions=[{
+ 'type': 'blockdev-backup',
+ 'data': { 'device': 'drive0',
+ 'target': 'nonexistent',
+ 'sync': 'full' },
+ }
+ ])
+ self.assert_qmp(result, 'error/class', 'DeviceNotFound')
+
+ result = self.vm.qmp('transaction', actions=[{
+ 'type': 'blockdev-backup',
+ 'data': { 'device': 'nonexistent',
+ 'target': 'nonexistent',
+ 'sync': 'full' },
+ }
+ ])
+ self.assert_qmp(result, 'error/class', 'DeviceNotFound')
+
+ def test_target_is_source(self):
+ result = self.vm.qmp('transaction', actions=[{
+ 'type': 'blockdev-backup',
+ 'data': { 'device': 'drive0',
+ 'target': 'drive0',
+ 'sync': 'full' },
+ }
+ ])
+ self.assert_qmp(result, 'error/class', 'GenericError')
+
def test_abort(self):
result = self.vm.qmp('transaction', actions=[{
'type': 'drive-backup',
@@ -298,5 +463,31 @@ class TestSingleTransaction(iotests.QMPTestCase):
self.assert_qmp(result, 'error/class', 'GenericError')
self.assert_no_active_block_jobs()
+ result = self.vm.qmp('transaction', actions=[{
+ 'type': 'blockdev-backup',
+ 'data': { 'device': 'nonexistent',
+ 'target': 'drive1',
+ 'sync': 'full' },
+ }, {
+ 'type': 'Abort',
+ 'data': {},
+ }
+ ])
+ self.assert_qmp(result, 'error/class', 'GenericError')
+ self.assert_no_active_block_jobs()
+
+ result = self.vm.qmp('transaction', actions=[{
+ 'type': 'blockdev-backup',
+ 'data': { 'device': 'drive0',
+ 'target': 'nonexistent',
+ 'sync': 'full' },
+ }, {
+ 'type': 'Abort',
+ 'data': {},
+ }
+ ])
+ self.assert_qmp(result, 'error/class', 'GenericError')
+ self.assert_no_active_block_jobs()
+
if __name__ == '__main__':
iotests.main(supported_fmts=['raw', 'qcow2'])
diff --git a/tests/qemu-iotests/055.out b/tests/qemu-iotests/055.out
index 6323079..c6a10f8 100644
--- a/tests/qemu-iotests/055.out
+++ b/tests/qemu-iotests/055.out
@@ -1,5 +1,5 @@
-..............
+.....................
----------------------------------------------------------------------
-Ran 14 tests
+Ran 21 tests
OK
--
1.9.0
^ permalink raw reply related [flat|nested] 36+ messages in thread
* [Qemu-devel] [PATCH v17 14/14] qemu-iotests: Image fleecing test case 083
2014-03-10 7:25 [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
` (12 preceding siblings ...)
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 13/14] qemu-iotests: Test blockdev-backup in 055 Fam Zheng
@ 2014-03-10 7:26 ` Fam Zheng
2014-04-02 6:01 ` [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
14 siblings, 0 replies; 36+ messages in thread
From: Fam Zheng @ 2014-03-10 7:26 UTC (permalink / raw)
To: qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
This tests the workflow of creating a lightweight point-in-time snapshot
with blockdev-backup command and export it with built-in NBD server.
It's tested that after the snapshot it created, writing to the original
device doesn't change data that can be read from target with NBD.
Signed-off-by: Fam Zheng <famz@redhat.com>
---
tests/qemu-iotests/083 | 99 ++++++++++++++++++++++++++++++++++++++++++++++
tests/qemu-iotests/083.out | 5 +++
tests/qemu-iotests/group | 1 +
3 files changed, 105 insertions(+)
create mode 100755 tests/qemu-iotests/083
create mode 100644 tests/qemu-iotests/083.out
diff --git a/tests/qemu-iotests/083 b/tests/qemu-iotests/083
new file mode 100755
index 0000000..8be32d7
--- /dev/null
+++ b/tests/qemu-iotests/083
@@ -0,0 +1,99 @@
+#!/usr/bin/env python
+#
+# Tests for image fleecing (point in time snapshot export to NBD)
+#
+# Copyright (C) 2014 Red Hat, Inc.
+#
+# Based on 055.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+
+import time
+import os
+import iotests
+from iotests import qemu_img, qemu_io
+
+test_img = os.path.join(iotests.test_dir, 'test.img')
+target_img = os.path.join(iotests.test_dir, 'target.img')
+nbd_sock = os.path.join(iotests.test_dir, 'nbd.sock')
+
+class TestImageFleecing(iotests.QMPTestCase):
+ image_len = 64 * 1024 * 1024 # MB
+
+ def setUp(self):
+ # Write data to the image so we can compare later
+ qemu_img('create', '-f', iotests.imgfmt, test_img, str(TestImageFleecing.image_len))
+ self.patterns = [
+ ("0x5d", "0", "64k"),
+ ("0xd5", "1M", "64k"),
+ ("0xdc", "32M", "64k"),
+ ("0xdc", "67043328", "64k")]
+
+ for p in self.patterns:
+ qemu_io('-c', 'write -P%s %s %s' % p, test_img)
+
+ qemu_img('create', '-f', iotests.imgfmt, target_img, str(TestImageFleecing.image_len))
+
+ self.vm = iotests.VM().add_drive(test_img)
+ self.vm.launch()
+
+ self.overwrite_patterns = [
+ ("0xa0", "0", "64k"),
+ ("0x0a", "1M", "64k"),
+ ("0x55", "32M", "64k"),
+ ("0x56", "67043328", "64k")]
+
+ self.nbd_uri = "nbd+unix:///drive1?socket=%s" % nbd_sock
+
+ def tearDown(self):
+ self.vm.shutdown()
+ os.remove(test_img)
+ os.remove(target_img)
+
+ def verify_patterns(self):
+ for p in self.patterns:
+ self.assertEqual(-1, qemu_io(self.nbd_uri, '-c', 'read -P%s %s %s' % p).find("verification failed"),
+ "Failed to verify pattern: %s %s %s" % p)
+
+ def test_image_fleecing(self):
+ result = self.vm.qmp("blockdev-add", **{"options": {
+ "driver": "qcow2",
+ "id": "drive1",
+ "file": {
+ "driver": "file",
+ "filename": target_img,
+ },
+ "backing": "drive0",
+ }})
+ self.assert_qmp(result, 'return', {})
+ result = self.vm.qmp("nbd-server-start", **{"addr": { "type": "unix", "data": { "path": nbd_sock } } })
+ self.assert_qmp(result, 'return', {})
+ result = self.vm.qmp("blockdev-backup", device="drive0", target="drive1", sync="none")
+ self.assert_qmp(result, 'return', {})
+ result = self.vm.qmp("nbd-server-add", device="drive1")
+ self.assert_qmp(result, 'return', {})
+
+ self.verify_patterns()
+
+ for p in self.overwrite_patterns:
+ self.vm.hmp_qemu_io("drive0", "write -P%s %s %s" % p)
+
+ self.verify_patterns()
+
+ self.cancel_and_wait(resume=True)
+ self.assert_no_active_block_jobs()
+
+if __name__ == '__main__':
+ iotests.main(supported_fmts=['raw', 'qcow2'])
diff --git a/tests/qemu-iotests/083.out b/tests/qemu-iotests/083.out
new file mode 100644
index 0000000..ae1213e
--- /dev/null
+++ b/tests/qemu-iotests/083.out
@@ -0,0 +1,5 @@
+.
+----------------------------------------------------------------------
+Ran 1 tests
+
+OK
diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
index e96eafd..b96c6bc 100644
--- a/tests/qemu-iotests/group
+++ b/tests/qemu-iotests/group
@@ -85,6 +85,7 @@
079 rw auto
081 rw auto
082 rw auto quick
+083 rw auto quick
085 rw auto quick
086 rw auto quick
087 rw auto quick
--
1.9.0
^ permalink raw reply related [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD
2014-03-10 7:25 [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
` (13 preceding siblings ...)
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 14/14] qemu-iotests: Image fleecing test case 083 Fam Zheng
@ 2014-04-02 6:01 ` Fam Zheng
2014-04-03 1:53 ` Jeff Cody
14 siblings, 1 reply; 36+ messages in thread
From: Fam Zheng @ 2014-04-02 6:01 UTC (permalink / raw)
To: qemu-devel
Cc: kwolf, benoit.canet, armbru, jcody, rjones, ptoscano, imain,
stefanha, pbonzini
On Mon, 03/10 15:25, Fam Zheng wrote:
> v17: Rebase to current master.
Ping?
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD
2014-04-02 6:01 ` [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
@ 2014-04-03 1:53 ` Jeff Cody
0 siblings, 0 replies; 36+ messages in thread
From: Jeff Cody @ 2014-04-03 1:53 UTC (permalink / raw)
To: Fam Zheng
Cc: kwolf, benoit.canet, rjones, armbru, qemu-devel, ptoscano, imain,
stefanha, pbonzini
On Wed, Apr 02, 2014 at 02:01:55PM +0800, Fam Zheng wrote:
> On Mon, 03/10 15:25, Fam Zheng wrote:
> > v17: Rebase to current master.
>
> Ping?
Hi Fam,
Sorry, I'll try to finish up my review of v17 tomorrow.
Jeff
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 01/14] block: Add BlockOpType enum
2014-03-10 7:25 ` [Qemu-devel] [PATCH v17 01/14] block: Add BlockOpType enum Fam Zheng
@ 2014-04-06 23:47 ` Jeff Cody
0 siblings, 0 replies; 36+ messages in thread
From: Jeff Cody @ 2014-04-06 23:47 UTC (permalink / raw)
To: Fam Zheng
Cc: kwolf, benoit.canet, rjones, armbru, qemu-devel, ptoscano, imain,
stefanha, pbonzini
On Mon, Mar 10, 2014 at 03:25:57PM +0800, Fam Zheng wrote:
> This adds the enum of all the operations that can be taken on a block
> device.
>
> Signed-off-by: Fam Zheng <famz@redhat.com>
> Reviewed-by: Benoit Canet <benoit@irqsave.net>
> ---
> include/block/block.h | 19 +++++++++++++++++++
> 1 file changed, 19 insertions(+)
>
> diff --git a/include/block/block.h b/include/block/block.h
> index 780f48b..8820735 100644
> --- a/include/block/block.h
> +++ b/include/block/block.h
> @@ -154,6 +154,25 @@ typedef struct BDRVReopenState {
> void *opaque;
> } BDRVReopenState;
>
> +/*
> + * Block operation types
> + */
> +typedef enum BlockOpType {
> + BLOCK_OP_TYPE_BACKUP_SOURCE,
> + BLOCK_OP_TYPE_BACKUP_TARGET,
> + BLOCK_OP_TYPE_CHANGE,
> + BLOCK_OP_TYPE_COMMIT,
> + BLOCK_OP_TYPE_DATAPLANE,
> + BLOCK_OP_TYPE_DRIVE_DEL,
> + BLOCK_OP_TYPE_EJECT,
> + BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT,
> + BLOCK_OP_TYPE_INTERNAL_SNAPSHOT,
> + BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE,
> + BLOCK_OP_TYPE_MIRROR,
> + BLOCK_OP_TYPE_RESIZE,
> + BLOCK_OP_TYPE_STREAM,
> + BLOCK_OP_TYPE_MAX,
> +} BlockOpType;
>
> void bdrv_iostatus_enable(BlockDriverState *bs);
> void bdrv_iostatus_reset(BlockDriverState *bs);
> --
> 1.9.0
>
>
Reviewed-by: Jeff Cody <jcody@redhat.com>
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 02/14] block: Introduce op_blockers to BlockDriverState
2014-03-10 7:25 ` [Qemu-devel] [PATCH v17 02/14] block: Introduce op_blockers to BlockDriverState Fam Zheng
@ 2014-04-06 23:49 ` Jeff Cody
2014-04-08 6:56 ` Fam Zheng
0 siblings, 1 reply; 36+ messages in thread
From: Jeff Cody @ 2014-04-06 23:49 UTC (permalink / raw)
To: Fam Zheng
Cc: kwolf, benoit.canet, rjones, armbru, qemu-devel, ptoscano, imain,
stefanha, pbonzini
On Mon, Mar 10, 2014 at 03:25:58PM +0800, Fam Zheng wrote:
> BlockDriverState.op_blockers is an array of lists with BLOCK_OP_TYPE_MAX
> elements. Each list is a list of blockers of an operation type
> (BlockOpType), that marks this BDS as currently blocked for a certain
> type of operation with reason errors stored in the list. The rule of
> usage is:
>
> * BDS user who wants to take an operation should check if there's any
> blocker of the type with bdrv_op_is_blocked().
>
> * BDS user who wants to block certain types of operation, should call
> bdrv_op_block (or bdrv_op_block_all to block all types of operations,
> which is similar to the existing bdrv_set_in_use()).
>
> * A blocker is only referenced by op_blockers, so the lifecycle is
> managed by caller, and shouldn't be lost until unblock, so typically
> a caller does these:
>
> - Allocate a blocker with error_setg or similar, call bdrv_op_block()
> to block some operations.
> - Hold the blocker, do his job.
> - Unblock operations that it blocked, with the same reason pointer
> passed to bdrv_op_unblock().
> - Release the blocker with error_free().
Is there a reason to assume there will be atypical usages that don't
follow these steps? If not, could the Error reason resource be
allocated inside the block() operation if non-NULL, and freed inside
the unblock() operations?
>
> Signed-off-by: Fam Zheng <famz@redhat.com>
> Reviewed-by: Benoit Canet <benoit@irqsave.net>
> ---
> block.c | 75 +++++++++++++++++++++++++++++++++++++++++++++++
> include/block/block.h | 7 +++++
> include/block/block_int.h | 5 ++++
> 3 files changed, 87 insertions(+)
>
> diff --git a/block.c b/block.c
> index f1ef4b0..56a4433 100644
> --- a/block.c
> +++ b/block.c
> @@ -335,6 +335,7 @@ void bdrv_register(BlockDriver *bdrv)
> BlockDriverState *bdrv_new(const char *device_name)
> {
> BlockDriverState *bs;
> + int i;
>
> bs = g_malloc0(sizeof(BlockDriverState));
> QLIST_INIT(&bs->dirty_bitmaps);
> @@ -342,6 +343,9 @@ BlockDriverState *bdrv_new(const char *device_name)
> if (device_name[0] != '\0') {
> QTAILQ_INSERT_TAIL(&bdrv_states, bs, device_list);
> }
> + for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) {
> + QLIST_INIT(&bs->op_blockers[i]);
> + }
> bdrv_iostatus_disable(bs);
> notifier_list_init(&bs->close_notifiers);
> notifier_with_return_list_init(&bs->before_write_notifiers);
> @@ -1853,6 +1857,8 @@ static void bdrv_move_feature_fields(BlockDriverState *bs_dest,
> pstrcpy(bs_dest->device_name, sizeof(bs_dest->device_name),
> bs_src->device_name);
> bs_dest->device_list = bs_src->device_list;
> + memcpy(bs_dest->op_blockers, bs_src->op_blockers,
> + sizeof(bs_dest->op_blockers));
> }
>
> /*
> @@ -5151,6 +5157,75 @@ void bdrv_unref(BlockDriverState *bs)
> }
> }
>
> +struct BdrvOpBlocker {
> + Error *reason;
> + QLIST_ENTRY(BdrvOpBlocker) list;
> +};
> +
> +bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp)
> +{
> + BdrvOpBlocker *blocker;
> + assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX);
> + if (!QLIST_EMPTY(&bs->op_blockers[op])) {
> + blocker = QLIST_FIRST(&bs->op_blockers[op]);
> + if (errp) {
> + *errp = error_copy(blocker->reason);
> + }
The blocker assignment could be moved inside the if bracket (just an
observation, not a request)
Reviewed-by: Jeff Cody <jcody@redhat.com>
> + return true;
> + }
> + return false;
> +}
> +
> +void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason)
> +{
> + BdrvOpBlocker *blocker;
> + assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX);
> +
> + blocker = g_malloc0(sizeof(BdrvOpBlocker));
> + blocker->reason = reason;
> + QLIST_INSERT_HEAD(&bs->op_blockers[op], blocker, list);
> +}
> +
> +void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason)
> +{
> + BdrvOpBlocker *blocker, *next;
> + assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX);
> + QLIST_FOREACH_SAFE(blocker, &bs->op_blockers[op], list, next) {
> + if (blocker->reason == reason) {
> + QLIST_REMOVE(blocker, list);
> + g_free(blocker);
> + }
> + }
> +}
> +
> +void bdrv_op_block_all(BlockDriverState *bs, Error *reason)
> +{
> + int i;
> + for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) {
> + bdrv_op_block(bs, i, reason);
> + }
> +}
> +
> +void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason)
> +{
> + int i;
> + for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) {
> + bdrv_op_unblock(bs, i, reason);
> + }
> +}
> +
> +bool bdrv_op_blocker_is_empty(BlockDriverState *bs)
> +{
> + int i;
> +
> + for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) {
> + if (!QLIST_EMPTY(&bs->op_blockers[i])) {
> + return false;
> + }
> + }
> + return true;
> +}
> +
> void bdrv_set_in_use(BlockDriverState *bs, int in_use)
> {
> assert(bs->in_use != in_use);
> diff --git a/include/block/block.h b/include/block/block.h
> index 8820735..4874e2a 100644
> --- a/include/block/block.h
> +++ b/include/block/block.h
> @@ -474,6 +474,13 @@ void bdrv_unref(BlockDriverState *bs);
> void bdrv_set_in_use(BlockDriverState *bs, int in_use);
> int bdrv_in_use(BlockDriverState *bs);
>
> +bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp);
> +void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason);
> +void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason);
> +void bdrv_op_block_all(BlockDriverState *bs, Error *reason);
> +void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason);
> +bool bdrv_op_blocker_is_empty(BlockDriverState *bs);
> +
> #ifdef CONFIG_LINUX_AIO
> int raw_get_aio_fd(BlockDriverState *bs);
> #else
> diff --git a/include/block/block_int.h b/include/block/block_int.h
> index 0bcf1c9..4e558d0 100644
> --- a/include/block/block_int.h
> +++ b/include/block/block_int.h
> @@ -270,6 +270,8 @@ typedef struct BlockLimits {
> size_t opt_mem_alignment;
> } BlockLimits;
>
> +typedef struct BdrvOpBlocker BdrvOpBlocker;
> +
> /*
> * Note: the function bdrv_append() copies and swaps contents of
> * BlockDriverStates, so if you add new fields to this struct, please
> @@ -361,6 +363,9 @@ struct BlockDriverState {
>
> QLIST_HEAD(, BdrvTrackedRequest) tracked_requests;
>
> + /* operation blockers */
> + QLIST_HEAD(, BdrvOpBlocker) op_blockers[BLOCK_OP_TYPE_MAX];
> +
> /* long-running background operation */
> BlockJob *job;
>
> --
> 1.9.0
>
>
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 04/14] block: Move op_blocker check from block_job_create to its caller
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 04/14] block: Move op_blocker check from block_job_create to its caller Fam Zheng
@ 2014-04-06 23:50 ` Jeff Cody
0 siblings, 0 replies; 36+ messages in thread
From: Jeff Cody @ 2014-04-06 23:50 UTC (permalink / raw)
To: Fam Zheng
Cc: kwolf, benoit.canet, rjones, armbru, qemu-devel, ptoscano, imain,
stefanha, pbonzini
On Mon, Mar 10, 2014 at 03:26:00PM +0800, Fam Zheng wrote:
> It makes no sense to check for "any" blocker on bs, we are here only
> because of the mechanical conversion from in_use to op_blockers. Remove
> it now, and let the callers check specific operation types. Backup and
> mirror already have it, add checker to stream and commit.
>
> Signed-off-by: Fam Zheng <famz@redhat.com>
> Reviewed-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Jeff Cody <jcody@redhat.com>
> ---
> blockdev.c | 8 ++++++++
> blockjob.c | 2 +-
> 2 files changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/blockdev.c b/blockdev.c
> index 593925e..d68fd2b 100644
> --- a/blockdev.c
> +++ b/blockdev.c
> @@ -1846,6 +1846,10 @@ void qmp_block_stream(const char *device, bool has_base,
> return;
> }
>
> + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_STREAM, errp)) {
> + return;
> + }
> +
> if (base) {
> base_bs = bdrv_find_backing_image(bs, base);
> if (base_bs == NULL) {
> @@ -1886,6 +1890,10 @@ void qmp_block_commit(const char *device,
> return;
> }
>
> + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT, errp)) {
> + return;
> + }
> +
> /* default top_bs is the active layer */
> top_bs = bs;
>
> diff --git a/blockjob.c b/blockjob.c
> index f643a78..3e33051 100644
> --- a/blockjob.c
> +++ b/blockjob.c
> @@ -41,7 +41,7 @@ void *block_job_create(const BlockJobDriver *driver, BlockDriverState *bs,
> {
> BlockJob *job;
>
> - if (bs->job || !bdrv_op_blocker_is_empty(bs)) {
> + if (bs->job) {
> error_set(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
> return NULL;
> }
> --
> 1.9.0
>
>
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 05/14] block: Add bdrv_set_backing_hd()
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 05/14] block: Add bdrv_set_backing_hd() Fam Zheng
@ 2014-04-07 0:01 ` Jeff Cody
0 siblings, 0 replies; 36+ messages in thread
From: Jeff Cody @ 2014-04-07 0:01 UTC (permalink / raw)
To: Fam Zheng
Cc: kwolf, benoit.canet, rjones, armbru, qemu-devel, ptoscano, imain,
stefanha, pbonzini
On Mon, Mar 10, 2014 at 03:26:01PM +0800, Fam Zheng wrote:
> This is the common but non-trivial steps to assign or change the
> backing_hd of BDS.
>
> Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
> ---
> block.c | 39 +++++++++++++++++++++++++--------------
> include/block/block.h | 1 +
> 2 files changed, 26 insertions(+), 14 deletions(-)
>
> diff --git a/block.c b/block.c
> index c79d5dc..64738dc 100644
> --- a/block.c
> +++ b/block.c
> @@ -1047,6 +1047,23 @@ fail:
> return ret;
> }
>
> +void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
> +{
> +
> + bs->backing_hd = backing_hd;
> + if (!backing_hd) {
> + bs->backing_file[0] = '\0';
> + bs->backing_format[0] = '\0';
> + goto out;
> + }
> + bs->open_flags &= ~BDRV_O_NO_BACKING;
> + pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename);
> + pstrcpy(bs->backing_format, sizeof(bs->backing_format),
> + backing_hd->drv ? backing_hd->drv->format_name : "");
> +out:
> + bdrv_refresh_limits(bs);
> +}
> +
> /*
> * Opens the backing file for a BlockDriverState if not yet open
> *
> @@ -1060,6 +1077,7 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp)
> char backing_filename[PATH_MAX];
> int back_flags, ret;
> BlockDriver *back_drv = NULL;
> + BlockDriverState *backing_hd;
> Error *local_err = NULL;
>
> if (bs->backing_hd != NULL) {
> @@ -1083,6 +1101,8 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp)
> sizeof(backing_filename));
> }
>
> + backing_hd = bdrv_new("");
> +
> if (bs->backing_format[0] != '\0') {
> back_drv = bdrv_find_format(bs->backing_format);
> }
> @@ -1091,23 +1111,19 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp)
> back_flags = bs->open_flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT |
> BDRV_O_COPY_ON_READ);
>
> - assert(bs->backing_hd == NULL);
> - ret = bdrv_open(&bs->backing_hd,
> + ret = bdrv_open(&backing_hd,
> *backing_filename ? backing_filename : NULL, NULL, options,
> back_flags, back_drv, &local_err);
> if (ret < 0) {
> - bs->backing_hd = NULL;
> + bdrv_unref(backing_hd);
> + backing_hd = NULL;
> bs->open_flags |= BDRV_O_NO_BACKING;
> error_setg(errp, "Could not open backing file: %s",
> error_get_pretty(local_err));
> error_free(local_err);
> return ret;
> }
> -
> - if (bs->backing_hd->file) {
> - pstrcpy(bs->backing_file, sizeof(bs->backing_file),
> - bs->backing_hd->file->filename);
> - }
> + bdrv_set_backing_hd(bs, backing_hd);
>
> /* Recalculate the BlockLimits with the backing file */
> bdrv_refresh_limits(bs);
> @@ -1944,12 +1960,7 @@ void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top)
>
> /* The contents of 'tmp' will become bs_top, as we are
> * swapping bs_new and bs_top contents. */
> - bs_top->backing_hd = bs_new;
> - bs_top->open_flags &= ~BDRV_O_NO_BACKING;
> - pstrcpy(bs_top->backing_file, sizeof(bs_top->backing_file),
> - bs_new->filename);
> - pstrcpy(bs_top->backing_format, sizeof(bs_top->backing_format),
> - bs_new->drv ? bs_new->drv->format_name : "");
> + bdrv_set_backing_hd(bs_top, bs_new);
> }
>
> static void bdrv_delete(BlockDriverState *bs)
> diff --git a/include/block/block.h b/include/block/block.h
> index a46f70a..ee1582d 100644
> --- a/include/block/block.h
> +++ b/include/block/block.h
> @@ -208,6 +208,7 @@ int bdrv_parse_discard_flags(const char *mode, int *flags);
> int bdrv_open_image(BlockDriverState **pbs, const char *filename,
> QDict *options, const char *bdref_key, int flags,
> bool allow_none, Error **errp);
> +void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd);
> int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp);
> int bdrv_open(BlockDriverState **pbs, const char *filename,
> const char *reference, QDict *options, int flags,
> --
> 1.9.0
>
>
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 03/14] block: Replace in_use with operation blocker
2014-03-10 7:25 ` [Qemu-devel] [PATCH v17 03/14] block: Replace in_use with operation blocker Fam Zheng
@ 2014-04-07 0:10 ` Jeff Cody
2014-04-07 0:24 ` Jeff Cody
0 siblings, 1 reply; 36+ messages in thread
From: Jeff Cody @ 2014-04-07 0:10 UTC (permalink / raw)
To: Fam Zheng
Cc: kwolf, benoit.canet, rjones, armbru, qemu-devel, ptoscano, imain,
stefanha, pbonzini
On Mon, Mar 10, 2014 at 03:25:59PM +0800, Fam Zheng wrote:
> This drops BlockDriverState.in_use with op_blockers:
>
> - Call bdrv_op_block_all in place of bdrv_set_in_use(bs, 1).
> - Call bdrv_op_unblock_all in place of bdrv_set_in_use(bs, 0).
> - Check bdrv_op_is_blocked() in place of bdrv_in_use(bs).
> The specific types are used, e.g. in place of starting block backup,
> bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP, ...).
> - Check bdrv_op_blocker_is_empty() in place of assert(!bs->in_use).
>
> Note: there is only bdrv_op_block_all and bdrv_op_unblock_all callers at
> this moment. So although the checks are specific to op types, this
> changes can still be seen as identical logic with previously with
> in_use. The difference is error message are improved because of blocker
> error info.
>
> Signed-off-by: Fam Zheng <famz@redhat.com>
> Signed-off-by: Markus Armbruster <armbru@redhat.com>
> ---
> block-migration.c | 7 +++++--
> block.c | 24 +++++++-----------------
> blockdev.c | 19 +++++++++----------
> blockjob.c | 14 +++++++++-----
> hw/block/dataplane/virtio-blk.c | 19 ++++++++++++-------
> include/block/block.h | 2 --
> include/block/block_int.h | 1 -
> include/block/blockjob.h | 3 +++
> 8 files changed, 45 insertions(+), 44 deletions(-)
>
> diff --git a/block-migration.c b/block-migration.c
> index 897fdba..bf9a25f 100644
> --- a/block-migration.c
> +++ b/block-migration.c
> @@ -59,6 +59,7 @@ typedef struct BlkMigDevState {
> unsigned long *aio_bitmap;
> int64_t completed_sectors;
> BdrvDirtyBitmap *dirty_bitmap;
> + Error *blocker;
> } BlkMigDevState;
>
> typedef struct BlkMigBlock {
> @@ -346,7 +347,8 @@ static void init_blk_migration_it(void *opaque, BlockDriverState *bs)
> bmds->completed_sectors = 0;
> bmds->shared_base = block_mig_state.shared_base;
> alloc_aio_bitmap(bmds);
> - bdrv_set_in_use(bs, 1);
> + error_setg(&bmds->blocker, "block device is in use by migration");
> + bdrv_op_block_all(bs, bmds->blocker);
> bdrv_ref(bs);
>
> block_mig_state.total_sector_sum += sectors;
> @@ -584,7 +586,8 @@ static void blk_mig_cleanup(void)
> blk_mig_lock();
> while ((bmds = QSIMPLEQ_FIRST(&block_mig_state.bmds_list)) != NULL) {
> QSIMPLEQ_REMOVE_HEAD(&block_mig_state.bmds_list, entry);
> - bdrv_set_in_use(bmds->bs, 0);
> + bdrv_op_unblock_all(bmds->bs, bmds->blocker);
> + error_free(bmds->blocker);
> bdrv_unref(bmds->bs);
> g_free(bmds->aio_bitmap);
> g_free(bmds);
> diff --git a/block.c b/block.c
> index 56a4433..c79d5dc 100644
> --- a/block.c
> +++ b/block.c
> @@ -1850,7 +1850,6 @@ static void bdrv_move_feature_fields(BlockDriverState *bs_dest,
> bs_dest->refcnt = bs_src->refcnt;
>
> /* job */
> - bs_dest->in_use = bs_src->in_use;
[1]
> bs_dest->job = bs_src->job;
>
> /* keep the same entry in bdrv_states */
> @@ -1893,7 +1892,7 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
> assert(QLIST_EMPTY(&bs_new->dirty_bitmaps));
> assert(bs_new->job == NULL);
> assert(bs_new->dev == NULL);
> - assert(bs_new->in_use == 0);
> + assert(bdrv_op_blocker_is_empty(bs_new));
Since we won't move the blocker via move_feature_fields() like we
did with in_use, do you think we should also assert on bs_old blocker
fields as well? I.e.:
assert(bdrv_op_blocker_is_empty(bs_old));
Or, alternatively, to keep the same behavior as in_use, preserve the
overlay bs blocker via bdrv_move_feature_field at [1] (see above)?
> assert(bs_new->io_limits_enabled == false);
> assert(!throttle_have_timer(&bs_new->throttle_state));
>
> @@ -1912,7 +1911,7 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
> /* Check a few fields that should remain attached to the device */
> assert(bs_new->dev == NULL);
> assert(bs_new->job == NULL);
> - assert(bs_new->in_use == 0);
> + assert(bdrv_op_blocker_is_empty(bs_new));
> assert(bs_new->io_limits_enabled == false);
> assert(!throttle_have_timer(&bs_new->throttle_state));
>
> @@ -1957,7 +1956,7 @@ static void bdrv_delete(BlockDriverState *bs)
> {
> assert(!bs->dev);
> assert(!bs->job);
> - assert(!bs->in_use);
> + assert(bdrv_op_blocker_is_empty(bs));
> assert(!bs->refcnt);
> assert(QLIST_EMPTY(&bs->dirty_bitmaps));
>
> @@ -2139,7 +2138,8 @@ int bdrv_commit(BlockDriverState *bs)
> return -ENOTSUP;
> }
>
> - if (bdrv_in_use(bs) || bdrv_in_use(bs->backing_hd)) {
> + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT, NULL) ||
> + bdrv_op_is_blocked(bs->backing_hd, BLOCK_OP_TYPE_COMMIT, NULL)) {
> return -EBUSY;
> }
>
> @@ -3374,8 +3374,9 @@ int bdrv_truncate(BlockDriverState *bs, int64_t offset)
> return -ENOTSUP;
> if (bs->read_only)
> return -EACCES;
> - if (bdrv_in_use(bs))
> + 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);
> @@ -5226,17 +5227,6 @@ bool bdrv_op_blocker_is_empty(BlockDriverState *bs)
> return true;
> }
>
> -void bdrv_set_in_use(BlockDriverState *bs, int in_use)
> -{
> - assert(bs->in_use != in_use);
> - bs->in_use = in_use;
> -}
> -
> -int bdrv_in_use(BlockDriverState *bs)
> -{
> - return bs->in_use;
> -}
> -
> void bdrv_iostatus_enable(BlockDriverState *bs)
> {
> bs->iostatus_enabled = true;
> diff --git a/blockdev.c b/blockdev.c
> index c3422a1..593925e 100644
> --- a/blockdev.c
> +++ b/blockdev.c
> @@ -1293,8 +1293,8 @@ static void external_snapshot_prepare(BlkTransactionState *common,
> return;
> }
>
> - if (bdrv_in_use(state->old_bs)) {
> - error_set(errp, QERR_DEVICE_IN_USE, device);
> + if (bdrv_op_is_blocked(state->old_bs,
> + BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, errp)) {
> return;
> }
>
> @@ -1516,8 +1516,7 @@ exit:
>
> static void eject_device(BlockDriverState *bs, int force, Error **errp)
> {
> - if (bdrv_in_use(bs)) {
> - error_set(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
> + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_EJECT, errp)) {
> return;
> }
> if (!bdrv_dev_has_removable_media(bs)) {
> @@ -1717,14 +1716,16 @@ int do_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data)
> {
> const char *id = qdict_get_str(qdict, "id");
> BlockDriverState *bs;
> + Error *local_err = NULL;
>
> bs = bdrv_find(id);
> if (!bs) {
> qerror_report(QERR_DEVICE_NOT_FOUND, id);
> return -1;
> }
> - if (bdrv_in_use(bs)) {
> - qerror_report(QERR_DEVICE_IN_USE, id);
> + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_DRIVE_DEL, &local_err)) {
> + error_report("%s", error_get_pretty(local_err));
> + error_free(local_err);
> return -1;
> }
>
> @@ -1976,8 +1977,7 @@ void qmp_drive_backup(const char *device, const char *target,
> }
> }
>
> - if (bdrv_in_use(bs)) {
> - error_set(errp, QERR_DEVICE_IN_USE, device);
> + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
> return;
> }
>
> @@ -2110,8 +2110,7 @@ void qmp_drive_mirror(const char *device, const char *target,
> }
> }
>
> - if (bdrv_in_use(bs)) {
> - error_set(errp, QERR_DEVICE_IN_USE, device);
> + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR, errp)) {
> return;
> }
>
> diff --git a/blockjob.c b/blockjob.c
> index b3ce14c..f643a78 100644
> --- a/blockjob.c
> +++ b/blockjob.c
> @@ -41,14 +41,16 @@ void *block_job_create(const BlockJobDriver *driver, BlockDriverState *bs,
> {
> BlockJob *job;
>
> - if (bs->job || bdrv_in_use(bs)) {
> + if (bs->job || !bdrv_op_blocker_is_empty(bs)) {
> error_set(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
> return NULL;
> }
> bdrv_ref(bs);
> - bdrv_set_in_use(bs, 1);
> -
> job = g_malloc0(driver->instance_size);
> + error_setg(&job->blocker, "block device is in use by block job: %s",
> + BlockJobType_lookup[driver->job_type]);
> + bdrv_op_block_all(bs, job->blocker);
> +
> job->driver = driver;
> job->bs = bs;
> job->cb = cb;
> @@ -63,8 +65,9 @@ void *block_job_create(const BlockJobDriver *driver, BlockDriverState *bs,
> block_job_set_speed(job, speed, &local_err);
> if (local_err) {
> bs->job = NULL;
> + bdrv_op_unblock_all(bs, job->blocker);
> + error_free(job->blocker);
> g_free(job);
> - bdrv_set_in_use(bs, 0);
> error_propagate(errp, local_err);
> return NULL;
> }
> @@ -79,8 +82,9 @@ void block_job_completed(BlockJob *job, int ret)
> assert(bs->job == job);
> job->cb(job->opaque, ret);
> bs->job = NULL;
> + bdrv_op_unblock_all(bs, job->blocker);
> + error_free(job->blocker);
> g_free(job);
> - bdrv_set_in_use(bs, 0);
> }
>
> void block_job_set_speed(BlockJob *job, int64_t speed, Error **errp)
> diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c
> index 2237edb..cee0aa5 100644
> --- a/hw/block/dataplane/virtio-blk.c
> +++ b/hw/block/dataplane/virtio-blk.c
> @@ -69,6 +69,9 @@ struct VirtIOBlockDataPlane {
> queue */
>
> unsigned int num_reqs;
> +
> + /* Operation blocker on BDS */
> + Error *blocker;
> };
>
> /* Raise an interrupt to signal guest, if necessary */
> @@ -368,6 +371,7 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *blk,
> {
> VirtIOBlockDataPlane *s;
> int fd;
> + Error *local_err = NULL;
>
> *dataplane = NULL;
>
> @@ -390,9 +394,10 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *blk,
> /* If dataplane is (re-)enabled while the guest is running there could be
> * block jobs that can conflict.
> */
> - if (bdrv_in_use(blk->conf.bs)) {
> - error_setg(errp,
> - "cannot start dataplane thread while device is in use");
> + if (bdrv_op_is_blocked(blk->conf.bs, BLOCK_OP_TYPE_DATAPLANE, &local_err)) {
> + error_report("cannot start dataplane thread: %s",
> + error_get_pretty(local_err));
> + error_free(local_err);
> return;
> }
>
> @@ -407,9 +412,8 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *blk,
> s->vdev = vdev;
> s->fd = fd;
> s->blk = blk;
> -
> - /* Prevent block operations that conflict with data plane thread */
> - bdrv_set_in_use(blk->conf.bs, 1);
> + error_setg(&s->blocker, "block device is in use by data plane");
> + bdrv_op_block_all(blk->conf.bs, s->blocker);
>
> *dataplane = s;
> }
> @@ -421,7 +425,8 @@ void virtio_blk_data_plane_destroy(VirtIOBlockDataPlane *s)
> }
>
> virtio_blk_data_plane_stop(s);
> - bdrv_set_in_use(s->blk->conf.bs, 0);
> + bdrv_op_unblock_all(s->blk->conf.bs, s->blocker);
> + error_free(s->blocker);
> g_free(s);
> }
>
> diff --git a/include/block/block.h b/include/block/block.h
> index 4874e2a..a46f70a 100644
> --- a/include/block/block.h
> +++ b/include/block/block.h
> @@ -471,8 +471,6 @@ void bdrv_disable_copy_on_read(BlockDriverState *bs);
>
> void bdrv_ref(BlockDriverState *bs);
> void bdrv_unref(BlockDriverState *bs);
> -void bdrv_set_in_use(BlockDriverState *bs, int in_use);
> -int bdrv_in_use(BlockDriverState *bs);
>
> bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp);
> void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason);
> diff --git a/include/block/block_int.h b/include/block/block_int.h
> index 4e558d0..1d3f76f 100644
> --- a/include/block/block_int.h
> +++ b/include/block/block_int.h
> @@ -359,7 +359,6 @@ struct BlockDriverState {
> QTAILQ_ENTRY(BlockDriverState) device_list;
> QLIST_HEAD(, BdrvDirtyBitmap) dirty_bitmaps;
> int refcnt;
> - int in_use; /* users other than guest access, eg. block migration */
>
> QLIST_HEAD(, BdrvTrackedRequest) tracked_requests;
>
> diff --git a/include/block/blockjob.h b/include/block/blockjob.h
> index d76de62..c0a7875 100644
> --- a/include/block/blockjob.h
> +++ b/include/block/blockjob.h
> @@ -106,6 +106,9 @@ struct BlockJob {
> /** The completion function that will be called when the job completes. */
> BlockDriverCompletionFunc *cb;
>
> + /** Block other operations when block job is running */
> + Error *blocker;
> +
> /** The opaque value that is passed to the completion function. */
> void *opaque;
> };
> --
> 1.9.0
>
>
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 03/14] block: Replace in_use with operation blocker
2014-04-07 0:10 ` Jeff Cody
@ 2014-04-07 0:24 ` Jeff Cody
0 siblings, 0 replies; 36+ messages in thread
From: Jeff Cody @ 2014-04-07 0:24 UTC (permalink / raw)
To: Fam Zheng
Cc: kwolf, benoit.canet, rjones, armbru, qemu-devel, ptoscano, imain,
stefanha, pbonzini
On Sun, Apr 06, 2014 at 08:10:58PM -0400, Jeff Cody wrote:
> On Mon, Mar 10, 2014 at 03:25:59PM +0800, Fam Zheng wrote:
> > This drops BlockDriverState.in_use with op_blockers:
> >
> > - Call bdrv_op_block_all in place of bdrv_set_in_use(bs, 1).
> > - Call bdrv_op_unblock_all in place of bdrv_set_in_use(bs, 0).
> > - Check bdrv_op_is_blocked() in place of bdrv_in_use(bs).
> > The specific types are used, e.g. in place of starting block backup,
> > bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP, ...).
> > - Check bdrv_op_blocker_is_empty() in place of assert(!bs->in_use).
> >
> > Note: there is only bdrv_op_block_all and bdrv_op_unblock_all callers at
> > this moment. So although the checks are specific to op types, this
> > changes can still be seen as identical logic with previously with
> > in_use. The difference is error message are improved because of blocker
> > error info.
> >
> > Signed-off-by: Fam Zheng <famz@redhat.com>
> > Signed-off-by: Markus Armbruster <armbru@redhat.com>
> > ---
> > block-migration.c | 7 +++++--
> > block.c | 24 +++++++-----------------
> > blockdev.c | 19 +++++++++----------
> > blockjob.c | 14 +++++++++-----
> > hw/block/dataplane/virtio-blk.c | 19 ++++++++++++-------
> > include/block/block.h | 2 --
> > include/block/block_int.h | 1 -
> > include/block/blockjob.h | 3 +++
> > 8 files changed, 45 insertions(+), 44 deletions(-)
> >
> > diff --git a/block-migration.c b/block-migration.c
> > index 897fdba..bf9a25f 100644
> > --- a/block-migration.c
> > +++ b/block-migration.c
> > @@ -59,6 +59,7 @@ typedef struct BlkMigDevState {
> > unsigned long *aio_bitmap;
> > int64_t completed_sectors;
> > BdrvDirtyBitmap *dirty_bitmap;
> > + Error *blocker;
> > } BlkMigDevState;
> >
> > typedef struct BlkMigBlock {
> > @@ -346,7 +347,8 @@ static void init_blk_migration_it(void *opaque, BlockDriverState *bs)
> > bmds->completed_sectors = 0;
> > bmds->shared_base = block_mig_state.shared_base;
> > alloc_aio_bitmap(bmds);
> > - bdrv_set_in_use(bs, 1);
> > + error_setg(&bmds->blocker, "block device is in use by migration");
> > + bdrv_op_block_all(bs, bmds->blocker);
> > bdrv_ref(bs);
> >
> > block_mig_state.total_sector_sum += sectors;
> > @@ -584,7 +586,8 @@ static void blk_mig_cleanup(void)
> > blk_mig_lock();
> > while ((bmds = QSIMPLEQ_FIRST(&block_mig_state.bmds_list)) != NULL) {
> > QSIMPLEQ_REMOVE_HEAD(&block_mig_state.bmds_list, entry);
> > - bdrv_set_in_use(bmds->bs, 0);
> > + bdrv_op_unblock_all(bmds->bs, bmds->blocker);
> > + error_free(bmds->blocker);
> > bdrv_unref(bmds->bs);
> > g_free(bmds->aio_bitmap);
> > g_free(bmds);
> > diff --git a/block.c b/block.c
> > index 56a4433..c79d5dc 100644
> > --- a/block.c
> > +++ b/block.c
> > @@ -1850,7 +1850,6 @@ static void bdrv_move_feature_fields(BlockDriverState *bs_dest,
> > bs_dest->refcnt = bs_src->refcnt;
> >
> > /* job */
> > - bs_dest->in_use = bs_src->in_use;
>
> [1]
>
> > bs_dest->job = bs_src->job;
> >
> > /* keep the same entry in bdrv_states */
> > @@ -1893,7 +1892,7 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
> > assert(QLIST_EMPTY(&bs_new->dirty_bitmaps));
> > assert(bs_new->job == NULL);
> > assert(bs_new->dev == NULL);
> > - assert(bs_new->in_use == 0);
> > + assert(bdrv_op_blocker_is_empty(bs_new));
>
> Since we won't move the blocker via move_feature_fields() like we
> did with in_use, do you think we should also assert on bs_old blocker
> fields as well? I.e.:
> assert(bdrv_op_blocker_is_empty(bs_old));
>
> Or, alternatively, to keep the same behavior as in_use, preserve the
> overlay bs blocker via bdrv_move_feature_field at [1] (see above)?
>
> > assert(bs_new->io_limits_enabled == false);
> > assert(!throttle_have_timer(&bs_new->throttle_state));
> >
> > @@ -1912,7 +1911,7 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
> > /* Check a few fields that should remain attached to the device */
> > assert(bs_new->dev == NULL);
> > assert(bs_new->job == NULL);
> > - assert(bs_new->in_use == 0);
> > + assert(bdrv_op_blocker_is_empty(bs_new));
Ah, my comment above is not relevant, because of this assert, that I
missed.
Reviewed-by: Jeff Cody <jcody@redhat.com>
> > assert(bs_new->io_limits_enabled == false);
> > assert(!throttle_have_timer(&bs_new->throttle_state));
> >
> > @@ -1957,7 +1956,7 @@ static void bdrv_delete(BlockDriverState *bs)
> > {
> > assert(!bs->dev);
> > assert(!bs->job);
> > - assert(!bs->in_use);
> > + assert(bdrv_op_blocker_is_empty(bs));
> > assert(!bs->refcnt);
> > assert(QLIST_EMPTY(&bs->dirty_bitmaps));
> >
> > @@ -2139,7 +2138,8 @@ int bdrv_commit(BlockDriverState *bs)
> > return -ENOTSUP;
> > }
> >
> > - if (bdrv_in_use(bs) || bdrv_in_use(bs->backing_hd)) {
> > + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT, NULL) ||
> > + bdrv_op_is_blocked(bs->backing_hd, BLOCK_OP_TYPE_COMMIT, NULL)) {
> > return -EBUSY;
> > }
> >
> > @@ -3374,8 +3374,9 @@ int bdrv_truncate(BlockDriverState *bs, int64_t offset)
> > return -ENOTSUP;
> > if (bs->read_only)
> > return -EACCES;
> > - if (bdrv_in_use(bs))
> > + 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);
> > @@ -5226,17 +5227,6 @@ bool bdrv_op_blocker_is_empty(BlockDriverState *bs)
> > return true;
> > }
> >
> > -void bdrv_set_in_use(BlockDriverState *bs, int in_use)
> > -{
> > - assert(bs->in_use != in_use);
> > - bs->in_use = in_use;
> > -}
> > -
> > -int bdrv_in_use(BlockDriverState *bs)
> > -{
> > - return bs->in_use;
> > -}
> > -
> > void bdrv_iostatus_enable(BlockDriverState *bs)
> > {
> > bs->iostatus_enabled = true;
> > diff --git a/blockdev.c b/blockdev.c
> > index c3422a1..593925e 100644
> > --- a/blockdev.c
> > +++ b/blockdev.c
> > @@ -1293,8 +1293,8 @@ static void external_snapshot_prepare(BlkTransactionState *common,
> > return;
> > }
> >
> > - if (bdrv_in_use(state->old_bs)) {
> > - error_set(errp, QERR_DEVICE_IN_USE, device);
> > + if (bdrv_op_is_blocked(state->old_bs,
> > + BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, errp)) {
> > return;
> > }
> >
> > @@ -1516,8 +1516,7 @@ exit:
> >
> > static void eject_device(BlockDriverState *bs, int force, Error **errp)
> > {
> > - if (bdrv_in_use(bs)) {
> > - error_set(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
> > + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_EJECT, errp)) {
> > return;
> > }
> > if (!bdrv_dev_has_removable_media(bs)) {
> > @@ -1717,14 +1716,16 @@ int do_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data)
> > {
> > const char *id = qdict_get_str(qdict, "id");
> > BlockDriverState *bs;
> > + Error *local_err = NULL;
> >
> > bs = bdrv_find(id);
> > if (!bs) {
> > qerror_report(QERR_DEVICE_NOT_FOUND, id);
> > return -1;
> > }
> > - if (bdrv_in_use(bs)) {
> > - qerror_report(QERR_DEVICE_IN_USE, id);
> > + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_DRIVE_DEL, &local_err)) {
> > + error_report("%s", error_get_pretty(local_err));
> > + error_free(local_err);
> > return -1;
> > }
> >
> > @@ -1976,8 +1977,7 @@ void qmp_drive_backup(const char *device, const char *target,
> > }
> > }
> >
> > - if (bdrv_in_use(bs)) {
> > - error_set(errp, QERR_DEVICE_IN_USE, device);
> > + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
> > return;
> > }
> >
> > @@ -2110,8 +2110,7 @@ void qmp_drive_mirror(const char *device, const char *target,
> > }
> > }
> >
> > - if (bdrv_in_use(bs)) {
> > - error_set(errp, QERR_DEVICE_IN_USE, device);
> > + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR, errp)) {
> > return;
> > }
> >
> > diff --git a/blockjob.c b/blockjob.c
> > index b3ce14c..f643a78 100644
> > --- a/blockjob.c
> > +++ b/blockjob.c
> > @@ -41,14 +41,16 @@ void *block_job_create(const BlockJobDriver *driver, BlockDriverState *bs,
> > {
> > BlockJob *job;
> >
> > - if (bs->job || bdrv_in_use(bs)) {
> > + if (bs->job || !bdrv_op_blocker_is_empty(bs)) {
> > error_set(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
> > return NULL;
> > }
> > bdrv_ref(bs);
> > - bdrv_set_in_use(bs, 1);
> > -
> > job = g_malloc0(driver->instance_size);
> > + error_setg(&job->blocker, "block device is in use by block job: %s",
> > + BlockJobType_lookup[driver->job_type]);
> > + bdrv_op_block_all(bs, job->blocker);
> > +
> > job->driver = driver;
> > job->bs = bs;
> > job->cb = cb;
> > @@ -63,8 +65,9 @@ void *block_job_create(const BlockJobDriver *driver, BlockDriverState *bs,
> > block_job_set_speed(job, speed, &local_err);
> > if (local_err) {
> > bs->job = NULL;
> > + bdrv_op_unblock_all(bs, job->blocker);
> > + error_free(job->blocker);
> > g_free(job);
> > - bdrv_set_in_use(bs, 0);
> > error_propagate(errp, local_err);
> > return NULL;
> > }
> > @@ -79,8 +82,9 @@ void block_job_completed(BlockJob *job, int ret)
> > assert(bs->job == job);
> > job->cb(job->opaque, ret);
> > bs->job = NULL;
> > + bdrv_op_unblock_all(bs, job->blocker);
> > + error_free(job->blocker);
> > g_free(job);
> > - bdrv_set_in_use(bs, 0);
> > }
> >
> > void block_job_set_speed(BlockJob *job, int64_t speed, Error **errp)
> > diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c
> > index 2237edb..cee0aa5 100644
> > --- a/hw/block/dataplane/virtio-blk.c
> > +++ b/hw/block/dataplane/virtio-blk.c
> > @@ -69,6 +69,9 @@ struct VirtIOBlockDataPlane {
> > queue */
> >
> > unsigned int num_reqs;
> > +
> > + /* Operation blocker on BDS */
> > + Error *blocker;
> > };
> >
> > /* Raise an interrupt to signal guest, if necessary */
> > @@ -368,6 +371,7 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *blk,
> > {
> > VirtIOBlockDataPlane *s;
> > int fd;
> > + Error *local_err = NULL;
> >
> > *dataplane = NULL;
> >
> > @@ -390,9 +394,10 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *blk,
> > /* If dataplane is (re-)enabled while the guest is running there could be
> > * block jobs that can conflict.
> > */
> > - if (bdrv_in_use(blk->conf.bs)) {
> > - error_setg(errp,
> > - "cannot start dataplane thread while device is in use");
> > + if (bdrv_op_is_blocked(blk->conf.bs, BLOCK_OP_TYPE_DATAPLANE, &local_err)) {
> > + error_report("cannot start dataplane thread: %s",
> > + error_get_pretty(local_err));
> > + error_free(local_err);
> > return;
> > }
> >
> > @@ -407,9 +412,8 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *blk,
> > s->vdev = vdev;
> > s->fd = fd;
> > s->blk = blk;
> > -
> > - /* Prevent block operations that conflict with data plane thread */
> > - bdrv_set_in_use(blk->conf.bs, 1);
> > + error_setg(&s->blocker, "block device is in use by data plane");
> > + bdrv_op_block_all(blk->conf.bs, s->blocker);
> >
> > *dataplane = s;
> > }
> > @@ -421,7 +425,8 @@ void virtio_blk_data_plane_destroy(VirtIOBlockDataPlane *s)
> > }
> >
> > virtio_blk_data_plane_stop(s);
> > - bdrv_set_in_use(s->blk->conf.bs, 0);
> > + bdrv_op_unblock_all(s->blk->conf.bs, s->blocker);
> > + error_free(s->blocker);
> > g_free(s);
> > }
> >
> > diff --git a/include/block/block.h b/include/block/block.h
> > index 4874e2a..a46f70a 100644
> > --- a/include/block/block.h
> > +++ b/include/block/block.h
> > @@ -471,8 +471,6 @@ void bdrv_disable_copy_on_read(BlockDriverState *bs);
> >
> > void bdrv_ref(BlockDriverState *bs);
> > void bdrv_unref(BlockDriverState *bs);
> > -void bdrv_set_in_use(BlockDriverState *bs, int in_use);
> > -int bdrv_in_use(BlockDriverState *bs);
> >
> > bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp);
> > void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason);
> > diff --git a/include/block/block_int.h b/include/block/block_int.h
> > index 4e558d0..1d3f76f 100644
> > --- a/include/block/block_int.h
> > +++ b/include/block/block_int.h
> > @@ -359,7 +359,6 @@ struct BlockDriverState {
> > QTAILQ_ENTRY(BlockDriverState) device_list;
> > QLIST_HEAD(, BdrvDirtyBitmap) dirty_bitmaps;
> > int refcnt;
> > - int in_use; /* users other than guest access, eg. block migration */
> >
> > QLIST_HEAD(, BdrvTrackedRequest) tracked_requests;
> >
> > diff --git a/include/block/blockjob.h b/include/block/blockjob.h
> > index d76de62..c0a7875 100644
> > --- a/include/block/blockjob.h
> > +++ b/include/block/blockjob.h
> > @@ -106,6 +106,9 @@ struct BlockJob {
> > /** The completion function that will be called when the job completes. */
> > BlockDriverCompletionFunc *cb;
> >
> > + /** Block other operations when block job is running */
> > + Error *blocker;
> > +
> > /** The opaque value that is passed to the completion function. */
> > void *opaque;
> > };
> > --
> > 1.9.0
> >
> >
>
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 06/14] block: Add backing_blocker in BlockDriverState
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 06/14] block: Add backing_blocker in BlockDriverState Fam Zheng
@ 2014-04-07 0:31 ` Jeff Cody
2014-04-08 7:37 ` Fam Zheng
2014-04-09 18:29 ` Jeff Cody
1 sibling, 1 reply; 36+ messages in thread
From: Jeff Cody @ 2014-04-07 0:31 UTC (permalink / raw)
To: Fam Zheng
Cc: kwolf, benoit.canet, rjones, armbru, qemu-devel, ptoscano, imain,
stefanha, pbonzini
On Mon, Mar 10, 2014 at 03:26:02PM +0800, Fam Zheng wrote:
> This makes use of op_blocker and blocks all the operations except for
> commit target, on each BlockDriverState->backing_hd.
>
> The asserts for op_blocker in bdrv_swap are removed because with this
> change, the target of block commit has at least the backing blocker of
> its child, so the assertion is not true. Callers should do their check.
>
> Signed-off-by: Fam Zheng <famz@redhat.com>
> ---
> block.c | 24 ++++++++++++++++++++----
> block/mirror.c | 1 +
> include/block/block_int.h | 3 +++
> 3 files changed, 24 insertions(+), 4 deletions(-)
>
> diff --git a/block.c b/block.c
> index 64738dc..95247c8 100644
> --- a/block.c
> +++ b/block.c
> @@ -1050,16 +1050,33 @@ fail:
> void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
> {
>
> + if (bs->backing_hd) {
> + assert(error_is_set(&bs->backing_blocker));
> + bdrv_op_unblock_all(bs->backing_hd, bs->backing_blocker);
> + } else if (backing_hd) {
> + error_setg(&bs->backing_blocker,
> + "device is used as backing hd of '%s'",
> + bs->device_name);
> + }
> +
> bs->backing_hd = backing_hd;
> if (!backing_hd) {
> bs->backing_file[0] = '\0';
> bs->backing_format[0] = '\0';
> + if (error_is_set(&bs->backing_blocker)) {
> + error_free(bs->backing_blocker);
> + }
> goto out;
> }
> bs->open_flags &= ~BDRV_O_NO_BACKING;
> pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename);
> pstrcpy(bs->backing_format, sizeof(bs->backing_format),
> backing_hd->drv ? backing_hd->drv->format_name : "");
> +
> + bdrv_op_block_all(bs->backing_hd, bs->backing_blocker);
> + /* Otherwise we won't be able to commit due to check in bdrv_commit */
> + bdrv_op_unblock(bs->backing_hd, BLOCK_OP_TYPE_COMMIT,
> + bs->backing_blocker);
> out:
> bdrv_refresh_limits(bs);
> }
> @@ -1699,8 +1716,9 @@ void bdrv_close(BlockDriverState *bs)
>
> if (bs->drv) {
> if (bs->backing_hd) {
> - bdrv_unref(bs->backing_hd);
> - bs->backing_hd = NULL;
> + BlockDriverState *backing_hd = bs->backing_hd;
> + bdrv_set_backing_hd(bs, NULL);
> + bdrv_unref(backing_hd);
> }
> bs->drv->bdrv_close(bs);
> g_free(bs->opaque);
> @@ -1908,7 +1926,6 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
> assert(QLIST_EMPTY(&bs_new->dirty_bitmaps));
> assert(bs_new->job == NULL);
> assert(bs_new->dev == NULL);
> - assert(bdrv_op_blocker_is_empty(bs_new));
> assert(bs_new->io_limits_enabled == false);
> assert(!throttle_have_timer(&bs_new->throttle_state));
>
> @@ -1927,7 +1944,6 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
> /* Check a few fields that should remain attached to the device */
> assert(bs_new->dev == NULL);
> assert(bs_new->job == NULL);
> - assert(bdrv_op_blocker_is_empty(bs_new));
Do we want to unswap the blocker field inside bdrv_move_feature_fields()
now?
> assert(bs_new->io_limits_enabled == false);
> assert(!throttle_have_timer(&bs_new->throttle_state));
>
> diff --git a/block/mirror.c b/block/mirror.c
> index dd5ee05..6dc84e8 100644
> --- a/block/mirror.c
> +++ b/block/mirror.c
> @@ -487,6 +487,7 @@ immediate_exit:
> * trigger the unref from the top one */
> BlockDriverState *p = s->base->backing_hd;
> s->base->backing_hd = NULL;
> + bdrv_op_unblock_all(p, s->base->backing_blocker);
> bdrv_unref(p);
> }
> }
> diff --git a/include/block/block_int.h b/include/block/block_int.h
> index 1d3f76f..1f4f78b 100644
> --- a/include/block/block_int.h
> +++ b/include/block/block_int.h
> @@ -369,6 +369,9 @@ struct BlockDriverState {
> BlockJob *job;
>
> QDict *options;
> +
> + /* The error object in use for blocking operations on backing_hd */
> + Error *backing_blocker;
> };
>
> int get_tmp_filename(char *filename, int size);
> --
> 1.9.0
>
>
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 08/14] block: Support dropping active in bdrv_drop_intermediate
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 08/14] block: Support dropping active in bdrv_drop_intermediate Fam Zheng
@ 2014-04-07 18:47 ` Jeff Cody
2014-04-08 8:15 ` Markus Armbruster
0 siblings, 1 reply; 36+ messages in thread
From: Jeff Cody @ 2014-04-07 18:47 UTC (permalink / raw)
To: Fam Zheng
Cc: kwolf, benoit.canet, rjones, armbru, qemu-devel, ptoscano, imain,
stefanha, pbonzini
On Mon, Mar 10, 2014 at 03:26:04PM +0800, Fam Zheng wrote:
> Dropping intermediate could be useful both for commit and stream, and
> BDS refcnt plus bdrv_swap could do most of the job nicely. It also needs
> to work with op blockers.
>
> Signed-off-by: Fam Zheng <famz@redhat.com>
> ---
> block.c | 139 ++++++++++++++++++++++++++++-----------------------------
> block/commit.c | 2 +-
> 2 files changed, 70 insertions(+), 71 deletions(-)
>
> diff --git a/block.c b/block.c
> index 05f7766..0af7c62 100644
> --- a/block.c
> +++ b/block.c
> @@ -2503,115 +2503,114 @@ BlockDriverState *bdrv_find_overlay(BlockDriverState *active,
> return overlay;
> }
>
> -typedef struct BlkIntermediateStates {
> - BlockDriverState *bs;
> - QSIMPLEQ_ENTRY(BlkIntermediateStates) entry;
> -} BlkIntermediateStates;
> -
> -
> /*
> - * Drops images above 'base' up to and including 'top', and sets the image
> - * above 'top' to have base as its backing file.
> + * Drops images above 'base' up to and including 'top', and sets new 'base' as
> + * backing_hd of top's overlay (the image orignally has 'top' as backing file).
> + * top's overlay may be NULL if 'top' is active, no such update needed.
> + * Requires that the top's overlay to 'top' is opened r/w.
> + *
> + * 1) This will convert the following chain:
> + *
> + * ... <- base <- ... <- top <- overlay <-... <- active
> *
> - * Requires that the overlay to 'top' is opened r/w, so that the backing file
> - * information in 'bs' can be properly updated.
> + * to
> + *
> + * ... <- base <- overlay <- active
> + *
> + * 2) It is allowed for bottom==base, in which case it converts:
> *
> - * E.g., this will convert the following chain:
> - * bottom <- base <- intermediate <- top <- active
> + * base <- ... <- top <- overlay <- ... <- active
> *
> * to
> *
> - * bottom <- base <- active
> + * base <- overlay <- active
> *
> - * It is allowed for bottom==base, in which case it converts:
> + * 2) It also allows active==top, in which case it converts:
> *
> - * base <- intermediate <- top <- active
> + * ... <- base <- ... <- top (active)
> *
> * to
> *
> - * base <- active
> + * ... <- base == active == top
> + *
> + * i.e. only base and lower remains: *top == *base when return.
> + *
> + * 3) If base==NULL, it will drop all the BDS below overlay and set its
> + * backing_hd to NULL. I.e.:
> *
> - * Error conditions:
> - * if active == top, that is considered an error
> + * base(NULL) <- ... <- overlay <- ... <- active
> + *
> + * to
> + *
> + * overlay <- ... <- active
> *
> */
> int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top,
> BlockDriverState *base)
> {
> - BlockDriverState *intermediate;
> - BlockDriverState *base_bs = NULL;
> - BlockDriverState *new_top_bs = NULL;
> - BlkIntermediateStates *intermediate_state, *next;
> - int ret = -EIO;
> -
> - QSIMPLEQ_HEAD(states_to_delete, BlkIntermediateStates) states_to_delete;
> - QSIMPLEQ_INIT(&states_to_delete);
> + BlockDriverState *drop_start, *overlay, *bs;
> + int ret = -EINVAL;
>
> - if (!top->drv || !base->drv) {
> + assert(active);
> + assert(top);
> + /* Verify that top is in backing chain of active */
> + bs = active;
> + while (bs && bs != top) {
> + bs = bs->backing_hd;
> + }
> + if (!bs) {
> goto exit;
> }
> + /* Verify that base is in backing chain of top */
> + if (base) {
> + while (bs && bs != base) {
> + bs = bs->backing_hd;
> + }
> + if (bs != base) {
> + goto exit;
> + }
> + }
>
> - new_top_bs = bdrv_find_overlay(active, top);
> -
> - if (new_top_bs == NULL) {
> - /* we could not find the image above 'top', this is an error */
> + if (!top->drv || (base && !base->drv)) {
> goto exit;
> }
> -
> - /* special case of new_top_bs->backing_hd already pointing to base - nothing
> - * to do, no intermediate images */
> - if (new_top_bs->backing_hd == base) {
> + if (top == base) {
> + ret = 0;
> + goto exit;
> + } else if (top == active) {
> + assert(base);
> + drop_start = active->backing_hd;
> + bdrv_swap(active, base);
This will assert in block.c, in bdrv_swap, on the test for
anonymity of active. (For testing, I changed the active layer commit
in mirror to use bdrv_drop_intermediate()).
Unfortunately, there are other problems as well (anonymity could be
fixed by bdrv_make_anon(active)).
Using line numbers from my version of block.c, lines 1957, 1959, and
1960 will each cause an assert (these lines are all in bdrv_swap()):
1956: /* bs_new must be anonymous and shouldn't have anything fancy enabled */
1957: assert(bs_new->device_name[0] == '\0');
1958: assert(QLIST_EMPTY(&bs_new->dirty_bitmaps));
1959: assert(bs_new->job == NULL);
1960: assert(bs_new->dev == NULL);
Markus - on line 1960 above, is it safe to remove that check (and the
other check further down in bdrv_swap())?
Thinking about it more, there may be other landmines in bdrv_swap()
for this case; prior to this, bdrv_swap() was always called with
bs_new being a newly-created BDS. With the active layer BDS it almost
certainly is not 'new', and could have other "prohibited" fields set,
in addition to the above (e.g. io limits, etc.)
> + base->backing_hd = NULL;
> + bdrv_unref(drop_start);
> ret = 0;
> goto exit;
> }
>
> - intermediate = top;
> -
> - /* now we will go down through the list, and add each BDS we find
> - * into our deletion queue, until we hit the 'base'
> - */
> - while (intermediate) {
> - intermediate_state = g_malloc0(sizeof(BlkIntermediateStates));
> - intermediate_state->bs = intermediate;
> - QSIMPLEQ_INSERT_TAIL(&states_to_delete, intermediate_state, entry);
> -
> - if (intermediate->backing_hd == base) {
> - base_bs = intermediate->backing_hd;
> - break;
> - }
> - intermediate = intermediate->backing_hd;
> - }
> - if (base_bs == NULL) {
> - /* something went wrong, we did not end at the base. safely
> - * unravel everything, and exit with error */
> + overlay = bdrv_find_overlay(active, top);
> + if (!overlay) {
> goto exit;
> }
> -
> - /* success - we can delete the intermediate states, and link top->base */
> - ret = bdrv_change_backing_file(new_top_bs, base_bs->filename,
> - base_bs->drv ? base_bs->drv->format_name : "");
> + ret = bdrv_change_backing_file(overlay,
> + base ? base->filename : NULL,
> + base ? base->drv->format_name : NULL);
> if (ret) {
> goto exit;
> }
> - new_top_bs->backing_hd = base_bs;
>
> - bdrv_refresh_limits(new_top_bs);
> -
> - QSIMPLEQ_FOREACH_SAFE(intermediate_state, &states_to_delete, entry, next) {
> - /* so that bdrv_close() does not recursively close the chain */
> - intermediate_state->bs->backing_hd = NULL;
> - bdrv_unref(intermediate_state->bs);
> + bs = overlay->backing_hd;
> + bdrv_set_backing_hd(overlay, base);
> + if (base) {
> + bdrv_ref(base);
> + }
> + if (bs) {
> + bdrv_unref(bs);
> }
> ret = 0;
> -
> exit:
> - QSIMPLEQ_FOREACH_SAFE(intermediate_state, &states_to_delete, entry, next) {
> - g_free(intermediate_state);
> - }
> return ret;
> }
>
> -
> static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset,
> size_t size)
> {
> diff --git a/block/commit.c b/block/commit.c
> index acec4ac..ac598d6 100644
> --- a/block/commit.c
> +++ b/block/commit.c
> @@ -73,6 +73,7 @@ static void coroutine_fn commit_run(void *opaque)
> int bytes_written = 0;
> int64_t base_len;
>
> + overlay_bs = bdrv_find_overlay(active, top);
> ret = s->common.len = bdrv_getlength(top);
>
>
> @@ -154,7 +155,6 @@ exit_restore_reopen:
> if (s->base_flags != bdrv_get_flags(base)) {
> bdrv_reopen(base, s->base_flags, NULL);
> }
> - overlay_bs = bdrv_find_overlay(active, top);
> if (overlay_bs && s->orig_overlay_flags != bdrv_get_flags(overlay_bs)) {
> bdrv_reopen(overlay_bs, s->orig_overlay_flags, NULL);
> }
> --
> 1.9.0
>
>
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 10/14] qmp: Add command 'blockdev-backup'
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 10/14] qmp: Add command 'blockdev-backup' Fam Zheng
@ 2014-04-07 21:07 ` Eric Blake
2014-04-08 7:00 ` Fam Zheng
0 siblings, 1 reply; 36+ messages in thread
From: Eric Blake @ 2014-04-07 21:07 UTC (permalink / raw)
To: Fam Zheng, qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
[-- Attachment #1: Type: text/plain, Size: 2646 bytes --]
On 03/10/2014 01:26 AM, Fam Zheng wrote:
> Similar to drive-backup, but this command uses a device id as target
> instead of creating/opening an image file.
>
> Also add blocker on target bs, since the target is also a named device
> now.
>
> Add check and report error for bs == target which became possible but is
> an illegal case with introduction of blockdev-backup.
>
> Signed-off-by: Fam Zheng <famz@redhat.com>
> ---
> block/backup.c | 26 ++++++++++++++++++++++++++
> blockdev.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
> qapi-schema.json | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
> qmp-commands.hx | 44 ++++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 166 insertions(+)
Reviewing just QAPI portion:
> +++ b/qapi-schema.json
> @@ -1919,6 +1919,40 @@
> '*on-target-error': 'BlockdevOnError' } }
>
> ##
> +# @BlockdevBackup
> +#
> +# @device: the name of the device which should be copied.
> +#
> +# @target: the name of the backup target device.
> +#
> +# @sync: what parts of the disk image should be copied to the destination
> +# (all the disk, only the sectors allocated in the topmost image, or
> +# only new I/O).
> +#
> +# @speed: #optional the maximum speed, in bytes per second.
> +#
> +# @on-source-error: #optional the action to take on an error on the source,
> +# default 'report'. 'stop' and 'enospc' can only be used
> +# if the block device supports io-status (see BlockInfo).
> +#
> +# @on-target-error: #optional the action to take on an error on the target,
> +# default 'report' (no limitations, since this applies to
> +# a different block device than @device).
> +#
> +# Note that @on-source-error and @on-target-error only affect background I/O.
> +# If an error occurs during a guest write request, the device's rerror/werror
> +# actions will be used.
> +#
> +# Since: 2.0
2.1 now
> +##
> +{ 'type': 'BlockdevBackup',
> + 'data': { 'device': 'str', 'target': 'str',
> + 'sync': 'MirrorSyncMode',
> + '*speed': 'int',
> + '*on-source-error': 'BlockdevOnError',
> + '*on-target-error': 'BlockdevOnError' } }
> +
Looks reasonable
> +# If @device or @target is not a valid block device, DeviceNotFound.
> +#
> +# Since 2.0
> +##
> +{ 'command': 'blockdev-backup', 'data': 'BlockdevBackup' }
Another case of 2.1
--
Eric Blake eblake redhat com +1-919-301-3266
Libvirt virtualization library http://libvirt.org
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 604 bytes --]
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 12/14] block: Add blockdev-backup to transaction
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 12/14] block: Add blockdev-backup to transaction Fam Zheng
@ 2014-04-07 21:11 ` Eric Blake
2014-04-10 2:15 ` Fam Zheng
0 siblings, 1 reply; 36+ messages in thread
From: Eric Blake @ 2014-04-07 21:11 UTC (permalink / raw)
To: Fam Zheng, qemu-devel
Cc: kwolf, benoit.canet, rjones, jcody, armbru, ptoscano, imain,
stefanha, pbonzini
[-- Attachment #1: Type: text/plain, Size: 1180 bytes --]
On 03/10/2014 01:26 AM, Fam Zheng wrote:
> Signed-off-by: Fam Zheng <famz@redhat.com>
> ---
> blockdev.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
> qapi-schema.json | 1 +
> 2 files changed, 49 insertions(+)
>
> +++ b/qapi-schema.json
> @@ -1972,6 +1972,7 @@
> 'data': {
> 'blockdev-snapshot-sync': 'BlockdevSnapshot',
> 'drive-backup': 'DriveBackup',
> + 'blockdev-backup': 'BlockdevBackup',
> 'abort': 'Abort',
> 'blockdev-snapshot-internal-sync': 'BlockdevSnapshotInternal'
> } }
It might be nice to mention that the union was expanded in 2.1;
something like:
# A discriminated record of operations that can be performed with
# @transaction.
#
# Since 1.1, blockdev-backup since 2.1
##
{ 'union': 'TransactionAction',
Of course, this is a pre-existing problem, as we've added other actions
since 1.1 (blockdev-snapshot-internal-sync in 1.7, for example), so it
could be justified as a separate patch. But it can't hurt to start
being more thorough in our docs.
--
Eric Blake eblake redhat com +1-919-301-3266
Libvirt virtualization library http://libvirt.org
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 604 bytes --]
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 02/14] block: Introduce op_blockers to BlockDriverState
2014-04-06 23:49 ` Jeff Cody
@ 2014-04-08 6:56 ` Fam Zheng
0 siblings, 0 replies; 36+ messages in thread
From: Fam Zheng @ 2014-04-08 6:56 UTC (permalink / raw)
To: Jeff Cody
Cc: kwolf, benoit.canet, rjones, armbru, qemu-devel, ptoscano, imain,
stefanha, pbonzini
On Sun, 04/06 19:49, Jeff Cody wrote:
> On Mon, Mar 10, 2014 at 03:25:58PM +0800, Fam Zheng wrote:
> > BlockDriverState.op_blockers is an array of lists with BLOCK_OP_TYPE_MAX
> > elements. Each list is a list of blockers of an operation type
> > (BlockOpType), that marks this BDS as currently blocked for a certain
> > type of operation with reason errors stored in the list. The rule of
> > usage is:
> >
> > * BDS user who wants to take an operation should check if there's any
> > blocker of the type with bdrv_op_is_blocked().
> >
> > * BDS user who wants to block certain types of operation, should call
> > bdrv_op_block (or bdrv_op_block_all to block all types of operations,
> > which is similar to the existing bdrv_set_in_use()).
> >
> > * A blocker is only referenced by op_blockers, so the lifecycle is
> > managed by caller, and shouldn't be lost until unblock, so typically
> > a caller does these:
> >
> > - Allocate a blocker with error_setg or similar, call bdrv_op_block()
> > to block some operations.
> > - Hold the blocker, do his job.
> > - Unblock operations that it blocked, with the same reason pointer
> > passed to bdrv_op_unblock().
> > - Release the blocker with error_free().
>
> Is there a reason to assume there will be atypical usages that don't
> follow these steps? If not, could the Error reason resource be
> allocated inside the block() operation if non-NULL, and freed inside
> the unblock() operations?
Could work as well. It's just that the current interface is following the style
of migration blocker.
Thanks,
Fam
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 10/14] qmp: Add command 'blockdev-backup'
2014-04-07 21:07 ` Eric Blake
@ 2014-04-08 7:00 ` Fam Zheng
0 siblings, 0 replies; 36+ messages in thread
From: Fam Zheng @ 2014-04-08 7:00 UTC (permalink / raw)
To: Eric Blake
Cc: kwolf, benoit.canet, rjones, jcody, qemu-devel, armbru, imain,
stefanha, pbonzini, ptoscano
On Mon, 04/07 15:07, Eric Blake wrote:
> On 03/10/2014 01:26 AM, Fam Zheng wrote:
> > Similar to drive-backup, but this command uses a device id as target
> > instead of creating/opening an image file.
> >
> > Also add blocker on target bs, since the target is also a named device
> > now.
> >
> > Add check and report error for bs == target which became possible but is
> > an illegal case with introduction of blockdev-backup.
> >
> > Signed-off-by: Fam Zheng <famz@redhat.com>
> > ---
> > block/backup.c | 26 ++++++++++++++++++++++++++
> > blockdev.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
> > qapi-schema.json | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
> > qmp-commands.hx | 44 ++++++++++++++++++++++++++++++++++++++++++++
> > 4 files changed, 166 insertions(+)
>
> Reviewing just QAPI portion:
>
>
> > +++ b/qapi-schema.json
> > @@ -1919,6 +1919,40 @@
> > '*on-target-error': 'BlockdevOnError' } }
> >
> > ##
> > +# @BlockdevBackup
> > +#
> > +# @device: the name of the device which should be copied.
> > +#
> > +# @target: the name of the backup target device.
> > +#
> > +# @sync: what parts of the disk image should be copied to the destination
> > +# (all the disk, only the sectors allocated in the topmost image, or
> > +# only new I/O).
> > +#
> > +# @speed: #optional the maximum speed, in bytes per second.
> > +#
> > +# @on-source-error: #optional the action to take on an error on the source,
> > +# default 'report'. 'stop' and 'enospc' can only be used
> > +# if the block device supports io-status (see BlockInfo).
> > +#
> > +# @on-target-error: #optional the action to take on an error on the target,
> > +# default 'report' (no limitations, since this applies to
> > +# a different block device than @device).
> > +#
> > +# Note that @on-source-error and @on-target-error only affect background I/O.
> > +# If an error occurs during a guest write request, the device's rerror/werror
> > +# actions will be used.
> > +#
> > +# Since: 2.0
>
> 2.1 now
>
> > +##
> > +{ 'type': 'BlockdevBackup',
> > + 'data': { 'device': 'str', 'target': 'str',
> > + 'sync': 'MirrorSyncMode',
> > + '*speed': 'int',
> > + '*on-source-error': 'BlockdevOnError',
> > + '*on-target-error': 'BlockdevOnError' } }
> > +
>
> Looks reasonable
>
>
> > +# If @device or @target is not a valid block device, DeviceNotFound.
> > +#
> > +# Since 2.0
> > +##
> > +{ 'command': 'blockdev-backup', 'data': 'BlockdevBackup' }
>
> Another case of 2.1
Yes, thanks!
Fam
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 06/14] block: Add backing_blocker in BlockDriverState
2014-04-07 0:31 ` Jeff Cody
@ 2014-04-08 7:37 ` Fam Zheng
0 siblings, 0 replies; 36+ messages in thread
From: Fam Zheng @ 2014-04-08 7:37 UTC (permalink / raw)
To: Jeff Cody
Cc: kwolf, benoit.canet, rjones, armbru, qemu-devel, ptoscano, imain,
stefanha, pbonzini
On Sun, 04/06 20:31, Jeff Cody wrote:
> On Mon, Mar 10, 2014 at 03:26:02PM +0800, Fam Zheng wrote:
> > This makes use of op_blocker and blocks all the operations except for
> > commit target, on each BlockDriverState->backing_hd.
> >
> > The asserts for op_blocker in bdrv_swap are removed because with this
> > change, the target of block commit has at least the backing blocker of
> > its child, so the assertion is not true. Callers should do their check.
> >
> > Signed-off-by: Fam Zheng <famz@redhat.com>
> > ---
> > block.c | 24 ++++++++++++++++++++----
> > block/mirror.c | 1 +
> > include/block/block_int.h | 3 +++
> > 3 files changed, 24 insertions(+), 4 deletions(-)
> >
> > diff --git a/block.c b/block.c
> > index 64738dc..95247c8 100644
> > --- a/block.c
> > +++ b/block.c
> > @@ -1050,16 +1050,33 @@ fail:
> > void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
> > {
> >
> > + if (bs->backing_hd) {
> > + assert(error_is_set(&bs->backing_blocker));
> > + bdrv_op_unblock_all(bs->backing_hd, bs->backing_blocker);
> > + } else if (backing_hd) {
> > + error_setg(&bs->backing_blocker,
> > + "device is used as backing hd of '%s'",
> > + bs->device_name);
> > + }
> > +
> > bs->backing_hd = backing_hd;
> > if (!backing_hd) {
> > bs->backing_file[0] = '\0';
> > bs->backing_format[0] = '\0';
> > + if (error_is_set(&bs->backing_blocker)) {
> > + error_free(bs->backing_blocker);
> > + }
> > goto out;
> > }
> > bs->open_flags &= ~BDRV_O_NO_BACKING;
> > pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename);
> > pstrcpy(bs->backing_format, sizeof(bs->backing_format),
> > backing_hd->drv ? backing_hd->drv->format_name : "");
> > +
> > + bdrv_op_block_all(bs->backing_hd, bs->backing_blocker);
> > + /* Otherwise we won't be able to commit due to check in bdrv_commit */
> > + bdrv_op_unblock(bs->backing_hd, BLOCK_OP_TYPE_COMMIT,
> > + bs->backing_blocker);
> > out:
> > bdrv_refresh_limits(bs);
> > }
> > @@ -1699,8 +1716,9 @@ void bdrv_close(BlockDriverState *bs)
> >
> > if (bs->drv) {
> > if (bs->backing_hd) {
> > - bdrv_unref(bs->backing_hd);
> > - bs->backing_hd = NULL;
> > + BlockDriverState *backing_hd = bs->backing_hd;
> > + bdrv_set_backing_hd(bs, NULL);
> > + bdrv_unref(backing_hd);
> > }
> > bs->drv->bdrv_close(bs);
> > g_free(bs->opaque);
> > @@ -1908,7 +1926,6 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
> > assert(QLIST_EMPTY(&bs_new->dirty_bitmaps));
> > assert(bs_new->job == NULL);
> > assert(bs_new->dev == NULL);
> > - assert(bdrv_op_blocker_is_empty(bs_new));
> > assert(bs_new->io_limits_enabled == false);
> > assert(!throttle_have_timer(&bs_new->throttle_state));
> >
> > @@ -1927,7 +1944,6 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
> > /* Check a few fields that should remain attached to the device */
> > assert(bs_new->dev == NULL);
> > assert(bs_new->job == NULL);
> > - assert(bdrv_op_blocker_is_empty(bs_new));
>
> Do we want to unswap the blocker field inside bdrv_move_feature_fields()
> now?
Conceptually a BDS's blocker is a "feature field" (whatever it is) that
shouldn't be swapped by bdrv_swap(), just as .device_name and .refcnt. So it is
added to bdrv_move_feature_fields() since introduced, in patch 02.
Are you seeing any issue with this?
Fam
>
> > assert(bs_new->io_limits_enabled == false);
> > assert(!throttle_have_timer(&bs_new->throttle_state));
> >
> > diff --git a/block/mirror.c b/block/mirror.c
> > index dd5ee05..6dc84e8 100644
> > --- a/block/mirror.c
> > +++ b/block/mirror.c
> > @@ -487,6 +487,7 @@ immediate_exit:
> > * trigger the unref from the top one */
> > BlockDriverState *p = s->base->backing_hd;
> > s->base->backing_hd = NULL;
> > + bdrv_op_unblock_all(p, s->base->backing_blocker);
> > bdrv_unref(p);
> > }
> > }
> > diff --git a/include/block/block_int.h b/include/block/block_int.h
> > index 1d3f76f..1f4f78b 100644
> > --- a/include/block/block_int.h
> > +++ b/include/block/block_int.h
> > @@ -369,6 +369,9 @@ struct BlockDriverState {
> > BlockJob *job;
> >
> > QDict *options;
> > +
> > + /* The error object in use for blocking operations on backing_hd */
> > + Error *backing_blocker;
> > };
> >
> > int get_tmp_filename(char *filename, int size);
> > --
> > 1.9.0
> >
> >
>
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 08/14] block: Support dropping active in bdrv_drop_intermediate
2014-04-07 18:47 ` Jeff Cody
@ 2014-04-08 8:15 ` Markus Armbruster
2014-04-08 9:07 ` Fam Zheng
0 siblings, 1 reply; 36+ messages in thread
From: Markus Armbruster @ 2014-04-08 8:15 UTC (permalink / raw)
To: Jeff Cody
Cc: kwolf, benoit.canet, Fam Zheng, qemu-devel, rjones, ptoscano,
imain, stefanha, pbonzini
Jeff Cody <jcody@redhat.com> writes:
> On Mon, Mar 10, 2014 at 03:26:04PM +0800, Fam Zheng wrote:
>> Dropping intermediate could be useful both for commit and stream, and
>> BDS refcnt plus bdrv_swap could do most of the job nicely. It also needs
>> to work with op blockers.
>>
>> Signed-off-by: Fam Zheng <famz@redhat.com>
>> ---
>> block.c | 139 ++++++++++++++++++++++++++++-----------------------------
>> block/commit.c | 2 +-
>> 2 files changed, 70 insertions(+), 71 deletions(-)
>>
>> diff --git a/block.c b/block.c
>> index 05f7766..0af7c62 100644
>> --- a/block.c
>> +++ b/block.c
>> @@ -2503,115 +2503,114 @@ BlockDriverState *bdrv_find_overlay(BlockDriverState *active,
>> return overlay;
>> }
>>
>> -typedef struct BlkIntermediateStates {
>> - BlockDriverState *bs;
>> - QSIMPLEQ_ENTRY(BlkIntermediateStates) entry;
>> -} BlkIntermediateStates;
>> -
>> -
>> /*
>> - * Drops images above 'base' up to and including 'top', and sets the image
>> - * above 'top' to have base as its backing file.
>> + * Drops images above 'base' up to and including 'top', and sets new 'base' as
>> + * backing_hd of top's overlay (the image orignally has 'top' as backing file).
>> + * top's overlay may be NULL if 'top' is active, no such update needed.
>> + * Requires that the top's overlay to 'top' is opened r/w.
>> + *
>> + * 1) This will convert the following chain:
>> + *
>> + * ... <- base <- ... <- top <- overlay <-... <- active
>> *
>> - * Requires that the overlay to 'top' is opened r/w, so that the backing file
>> - * information in 'bs' can be properly updated.
>> + * to
>> + *
>> + * ... <- base <- overlay <- active
>> + *
>> + * 2) It is allowed for bottom==base, in which case it converts:
>> *
>> - * E.g., this will convert the following chain:
>> - * bottom <- base <- intermediate <- top <- active
>> + * base <- ... <- top <- overlay <- ... <- active
>> *
>> * to
>> *
>> - * bottom <- base <- active
>> + * base <- overlay <- active
>> *
>> - * It is allowed for bottom==base, in which case it converts:
>> + * 2) It also allows active==top, in which case it converts:
>> *
>> - * base <- intermediate <- top <- active
>> + * ... <- base <- ... <- top (active)
>> *
>> * to
>> *
>> - * base <- active
>> + * ... <- base == active == top
>> + *
>> + * i.e. only base and lower remains: *top == *base when return.
>> + *
>> + * 3) If base==NULL, it will drop all the BDS below overlay and set its
>> + * backing_hd to NULL. I.e.:
>> *
>> - * Error conditions:
>> - * if active == top, that is considered an error
>> + * base(NULL) <- ... <- overlay <- ... <- active
>> + *
>> + * to
>> + *
>> + * overlay <- ... <- active
>> *
>> */
>> int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top,
>> BlockDriverState *base)
>> {
>> - BlockDriverState *intermediate;
>> - BlockDriverState *base_bs = NULL;
>> - BlockDriverState *new_top_bs = NULL;
>> - BlkIntermediateStates *intermediate_state, *next;
>> - int ret = -EIO;
>> -
>> - QSIMPLEQ_HEAD(states_to_delete, BlkIntermediateStates) states_to_delete;
>> - QSIMPLEQ_INIT(&states_to_delete);
>> + BlockDriverState *drop_start, *overlay, *bs;
>> + int ret = -EINVAL;
>>
>> - if (!top->drv || !base->drv) {
>> + assert(active);
>> + assert(top);
>> + /* Verify that top is in backing chain of active */
>> + bs = active;
>> + while (bs && bs != top) {
>> + bs = bs->backing_hd;
>> + }
>> + if (!bs) {
>> goto exit;
>> }
>> + /* Verify that base is in backing chain of top */
>> + if (base) {
>> + while (bs && bs != base) {
>> + bs = bs->backing_hd;
>> + }
>> + if (bs != base) {
>> + goto exit;
>> + }
>> + }
>>
>> - new_top_bs = bdrv_find_overlay(active, top);
>> -
>> - if (new_top_bs == NULL) {
>> - /* we could not find the image above 'top', this is an error */
>> + if (!top->drv || (base && !base->drv)) {
>> goto exit;
>> }
>> -
>> - /* special case of new_top_bs->backing_hd already pointing to base - nothing
>> - * to do, no intermediate images */
>> - if (new_top_bs->backing_hd == base) {
>> + if (top == base) {
>> + ret = 0;
>> + goto exit;
>> + } else if (top == active) {
>> + assert(base);
>> + drop_start = active->backing_hd;
>> + bdrv_swap(active, base);
>
> This will assert in block.c, in bdrv_swap, on the test for
> anonymity of active. (For testing, I changed the active layer commit
> in mirror to use bdrv_drop_intermediate()).
>
> Unfortunately, there are other problems as well (anonymity could be
> fixed by bdrv_make_anon(active)).
>
> Using line numbers from my version of block.c, lines 1957, 1959, and
> 1960 will each cause an assert (these lines are all in bdrv_swap()):
>
> 1956: /* bs_new must be anonymous and shouldn't have anything fancy
> enabled */
> 1957: assert(bs_new->device_name[0] == '\0');
> 1958: assert(QLIST_EMPTY(&bs_new->dirty_bitmaps));
> 1959: assert(bs_new->job == NULL);
> 1960: assert(bs_new->dev == NULL);
>
> Markus - on line 1960 above, is it safe to remove that check (and the
> other check further down in bdrv_swap())?
I guess you mean the one under /* Check a few fields that should remain
attached to the device */ by "the other check".
bdrv_swap() is a scary, scary function. It has a number of
preconditions, and we've tried to make them explicit in assertions.
The preconditions could be:
(0) Implicit. Or less politely said: unstated / unknown.
(1) Explicit, but wrong.
(2) Restrictions: the swapping code doesn't cover this state, but it
could be made to cover it, relaxing the precondition.
(3) Fundamental: the precondition cannot or should not be relaxed.
BDS member dev is is the back pointer for the device model property
pointing to the device model's backend. It must stay on top, and
bdrv_move_feature_fields() duly moves it, along with its buddies dev_ops
and dev_opaque. Obviously, only one of bdrv_old and bdrv_new can be on
top at the same time. bdrv_swap() currently assumes that bdrv_old is
the top one on entry. Feels like an instance of (3).
> Thinking about it more, there may be other landmines in bdrv_swap()
> for this case; prior to this, bdrv_swap() was always called with
> bs_new being a newly-created BDS. With the active layer BDS it almost
> certainly is not 'new', and could have other "prohibited" fields set,
> in addition to the above (e.g. io limits, etc.)
Hairy...
We talked about splitting BlockBackend off BDS with an axe. Do you
think that would make this series less hairy?
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 08/14] block: Support dropping active in bdrv_drop_intermediate
2014-04-08 8:15 ` Markus Armbruster
@ 2014-04-08 9:07 ` Fam Zheng
2014-04-09 18:12 ` Jeff Cody
0 siblings, 1 reply; 36+ messages in thread
From: Fam Zheng @ 2014-04-08 9:07 UTC (permalink / raw)
To: Markus Armbruster, jcody
Cc: kwolf, benoit.canet, qemu-devel, rjones, ptoscano, imain,
stefanha, pbonzini
On Tue, 04/08 10:15, Markus Armbruster wrote:
> Jeff Cody <jcody@redhat.com> writes:
>
> > On Mon, Mar 10, 2014 at 03:26:04PM +0800, Fam Zheng wrote:
> >> Dropping intermediate could be useful both for commit and stream, and
> >> BDS refcnt plus bdrv_swap could do most of the job nicely. It also needs
> >> to work with op blockers.
> >>
> >> Signed-off-by: Fam Zheng <famz@redhat.com>
> >> ---
> >> block.c | 139 ++++++++++++++++++++++++++++-----------------------------
> >> block/commit.c | 2 +-
> >> 2 files changed, 70 insertions(+), 71 deletions(-)
> >>
> >> diff --git a/block.c b/block.c
> >> index 05f7766..0af7c62 100644
> >> --- a/block.c
> >> +++ b/block.c
> >> @@ -2503,115 +2503,114 @@ BlockDriverState *bdrv_find_overlay(BlockDriverState *active,
> >> return overlay;
> >> }
> >>
> >> -typedef struct BlkIntermediateStates {
> >> - BlockDriverState *bs;
> >> - QSIMPLEQ_ENTRY(BlkIntermediateStates) entry;
> >> -} BlkIntermediateStates;
> >> -
> >> -
> >> /*
> >> - * Drops images above 'base' up to and including 'top', and sets the image
> >> - * above 'top' to have base as its backing file.
> >> + * Drops images above 'base' up to and including 'top', and sets new 'base' as
> >> + * backing_hd of top's overlay (the image orignally has 'top' as backing file).
> >> + * top's overlay may be NULL if 'top' is active, no such update needed.
> >> + * Requires that the top's overlay to 'top' is opened r/w.
> >> + *
> >> + * 1) This will convert the following chain:
> >> + *
> >> + * ... <- base <- ... <- top <- overlay <-... <- active
> >> *
> >> - * Requires that the overlay to 'top' is opened r/w, so that the backing file
> >> - * information in 'bs' can be properly updated.
> >> + * to
> >> + *
> >> + * ... <- base <- overlay <- active
> >> + *
> >> + * 2) It is allowed for bottom==base, in which case it converts:
> >> *
> >> - * E.g., this will convert the following chain:
> >> - * bottom <- base <- intermediate <- top <- active
> >> + * base <- ... <- top <- overlay <- ... <- active
> >> *
> >> * to
> >> *
> >> - * bottom <- base <- active
> >> + * base <- overlay <- active
> >> *
> >> - * It is allowed for bottom==base, in which case it converts:
> >> + * 2) It also allows active==top, in which case it converts:
> >> *
> >> - * base <- intermediate <- top <- active
> >> + * ... <- base <- ... <- top (active)
> >> *
> >> * to
> >> *
> >> - * base <- active
> >> + * ... <- base == active == top
> >> + *
> >> + * i.e. only base and lower remains: *top == *base when return.
> >> + *
> >> + * 3) If base==NULL, it will drop all the BDS below overlay and set its
> >> + * backing_hd to NULL. I.e.:
> >> *
> >> - * Error conditions:
> >> - * if active == top, that is considered an error
> >> + * base(NULL) <- ... <- overlay <- ... <- active
> >> + *
> >> + * to
> >> + *
> >> + * overlay <- ... <- active
> >> *
> >> */
> >> int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top,
> >> BlockDriverState *base)
> >> {
> >> - BlockDriverState *intermediate;
> >> - BlockDriverState *base_bs = NULL;
> >> - BlockDriverState *new_top_bs = NULL;
> >> - BlkIntermediateStates *intermediate_state, *next;
> >> - int ret = -EIO;
> >> -
> >> - QSIMPLEQ_HEAD(states_to_delete, BlkIntermediateStates) states_to_delete;
> >> - QSIMPLEQ_INIT(&states_to_delete);
> >> + BlockDriverState *drop_start, *overlay, *bs;
> >> + int ret = -EINVAL;
> >>
> >> - if (!top->drv || !base->drv) {
> >> + assert(active);
> >> + assert(top);
> >> + /* Verify that top is in backing chain of active */
> >> + bs = active;
> >> + while (bs && bs != top) {
> >> + bs = bs->backing_hd;
> >> + }
> >> + if (!bs) {
> >> goto exit;
> >> }
> >> + /* Verify that base is in backing chain of top */
> >> + if (base) {
> >> + while (bs && bs != base) {
> >> + bs = bs->backing_hd;
> >> + }
> >> + if (bs != base) {
> >> + goto exit;
> >> + }
> >> + }
> >>
> >> - new_top_bs = bdrv_find_overlay(active, top);
> >> -
> >> - if (new_top_bs == NULL) {
> >> - /* we could not find the image above 'top', this is an error */
> >> + if (!top->drv || (base && !base->drv)) {
> >> goto exit;
> >> }
> >> -
> >> - /* special case of new_top_bs->backing_hd already pointing to base - nothing
> >> - * to do, no intermediate images */
> >> - if (new_top_bs->backing_hd == base) {
> >> + if (top == base) {
> >> + ret = 0;
> >> + goto exit;
> >> + } else if (top == active) {
> >> + assert(base);
> >> + drop_start = active->backing_hd;
> >> + bdrv_swap(active, base);
> >
> > This will assert in block.c, in bdrv_swap, on the test for
> > anonymity of active. (For testing, I changed the active layer commit
> > in mirror to use bdrv_drop_intermediate()).
Jeff, you're right, because bdrv_swap requires first argument to be a "new"
BDS, while we are passing in an top BDS.
But what happens if we write bdrv_swap(base, active)?
> >
> > Unfortunately, there are other problems as well (anonymity could be
> > fixed by bdrv_make_anon(active)).
> >
> > Using line numbers from my version of block.c, lines 1957, 1959, and
> > 1960 will each cause an assert (these lines are all in bdrv_swap()):
> >
> > 1956: /* bs_new must be anonymous and shouldn't have anything fancy
> > enabled */
> > 1957: assert(bs_new->device_name[0] == '\0');
> > 1958: assert(QLIST_EMPTY(&bs_new->dirty_bitmaps));
> > 1959: assert(bs_new->job == NULL);
> > 1960: assert(bs_new->dev == NULL);
> >
> > Markus - on line 1960 above, is it safe to remove that check (and the
> > other check further down in bdrv_swap())?
>
> I guess you mean the one under /* Check a few fields that should remain
> attached to the device */ by "the other check".
>
> bdrv_swap() is a scary, scary function. It has a number of
> preconditions, and we've tried to make them explicit in assertions.
>
> The preconditions could be:
>
> (0) Implicit. Or less politely said: unstated / unknown.
>
> (1) Explicit, but wrong.
>
> (2) Restrictions: the swapping code doesn't cover this state, but it
> could be made to cover it, relaxing the precondition.
>
> (3) Fundamental: the precondition cannot or should not be relaxed.
>
> BDS member dev is is the back pointer for the device model property
> pointing to the device model's backend. It must stay on top, and
> bdrv_move_feature_fields() duly moves it, along with its buddies dev_ops
> and dev_opaque. Obviously, only one of bdrv_old and bdrv_new can be on
> top at the same time. bdrv_swap() currently assumes that bdrv_old is
> the top one on entry. Feels like an instance of (3).
>
> > Thinking about it more, there may be other landmines in bdrv_swap()
> > for this case; prior to this, bdrv_swap() was always called with
> > bs_new being a newly-created BDS. With the active layer BDS it almost
> > certainly is not 'new', and could have other "prohibited" fields set,
> > in addition to the above (e.g. io limits, etc.)
>
> Hairy...
>
> We talked about splitting BlockBackend off BDS with an axe. Do you
> think that would make this series less hairy?
Hopefully, because it will help us to get rid of bdrv_move_feature_fields. :)
But if we need to get rid of bdrv_swap, we need a generic "level of indirect"
between BDS and BDS user, so we don't need to worry about the validity of old
BDS pointers when we update the chain. Just like BlockBackend does at device
emulation side. That's an even bigger project.
Thanks,
Fam
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 08/14] block: Support dropping active in bdrv_drop_intermediate
2014-04-08 9:07 ` Fam Zheng
@ 2014-04-09 18:12 ` Jeff Cody
0 siblings, 0 replies; 36+ messages in thread
From: Jeff Cody @ 2014-04-09 18:12 UTC (permalink / raw)
To: Fam Zheng
Cc: kwolf, benoit.canet, rjones, Markus Armbruster, qemu-devel,
ptoscano, imain, stefanha, pbonzini
On Tue, Apr 08, 2014 at 05:07:38PM +0800, Fam Zheng wrote:
> On Tue, 04/08 10:15, Markus Armbruster wrote:
> > Jeff Cody <jcody@redhat.com> writes:
> >
> > > On Mon, Mar 10, 2014 at 03:26:04PM +0800, Fam Zheng wrote:
> > >> Dropping intermediate could be useful both for commit and stream, and
> > >> BDS refcnt plus bdrv_swap could do most of the job nicely. It also needs
> > >> to work with op blockers.
> > >>
> > >> Signed-off-by: Fam Zheng <famz@redhat.com>
> > >> ---
> > >> block.c | 139 ++++++++++++++++++++++++++++-----------------------------
> > >> block/commit.c | 2 +-
> > >> 2 files changed, 70 insertions(+), 71 deletions(-)
> > >>
> > >> diff --git a/block.c b/block.c
> > >> index 05f7766..0af7c62 100644
> > >> --- a/block.c
> > >> +++ b/block.c
> > >> @@ -2503,115 +2503,114 @@ BlockDriverState *bdrv_find_overlay(BlockDriverState *active,
> > >> return overlay;
> > >> }
> > >>
> > >> -typedef struct BlkIntermediateStates {
> > >> - BlockDriverState *bs;
> > >> - QSIMPLEQ_ENTRY(BlkIntermediateStates) entry;
> > >> -} BlkIntermediateStates;
> > >> -
> > >> -
> > >> /*
> > >> - * Drops images above 'base' up to and including 'top', and sets the image
> > >> - * above 'top' to have base as its backing file.
> > >> + * Drops images above 'base' up to and including 'top', and sets new 'base' as
> > >> + * backing_hd of top's overlay (the image orignally has 'top' as backing file).
> > >> + * top's overlay may be NULL if 'top' is active, no such update needed.
> > >> + * Requires that the top's overlay to 'top' is opened r/w.
> > >> + *
> > >> + * 1) This will convert the following chain:
> > >> + *
> > >> + * ... <- base <- ... <- top <- overlay <-... <- active
> > >> *
> > >> - * Requires that the overlay to 'top' is opened r/w, so that the backing file
> > >> - * information in 'bs' can be properly updated.
> > >> + * to
> > >> + *
> > >> + * ... <- base <- overlay <- active
> > >> + *
> > >> + * 2) It is allowed for bottom==base, in which case it converts:
> > >> *
> > >> - * E.g., this will convert the following chain:
> > >> - * bottom <- base <- intermediate <- top <- active
> > >> + * base <- ... <- top <- overlay <- ... <- active
> > >> *
> > >> * to
> > >> *
> > >> - * bottom <- base <- active
> > >> + * base <- overlay <- active
> > >> *
> > >> - * It is allowed for bottom==base, in which case it converts:
> > >> + * 2) It also allows active==top, in which case it converts:
> > >> *
> > >> - * base <- intermediate <- top <- active
> > >> + * ... <- base <- ... <- top (active)
> > >> *
> > >> * to
> > >> *
> > >> - * base <- active
> > >> + * ... <- base == active == top
> > >> + *
> > >> + * i.e. only base and lower remains: *top == *base when return.
> > >> + *
> > >> + * 3) If base==NULL, it will drop all the BDS below overlay and set its
> > >> + * backing_hd to NULL. I.e.:
> > >> *
> > >> - * Error conditions:
> > >> - * if active == top, that is considered an error
> > >> + * base(NULL) <- ... <- overlay <- ... <- active
> > >> + *
> > >> + * to
> > >> + *
> > >> + * overlay <- ... <- active
> > >> *
> > >> */
> > >> int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top,
> > >> BlockDriverState *base)
> > >> {
> > >> - BlockDriverState *intermediate;
> > >> - BlockDriverState *base_bs = NULL;
> > >> - BlockDriverState *new_top_bs = NULL;
> > >> - BlkIntermediateStates *intermediate_state, *next;
> > >> - int ret = -EIO;
> > >> -
> > >> - QSIMPLEQ_HEAD(states_to_delete, BlkIntermediateStates) states_to_delete;
> > >> - QSIMPLEQ_INIT(&states_to_delete);
> > >> + BlockDriverState *drop_start, *overlay, *bs;
> > >> + int ret = -EINVAL;
> > >>
> > >> - if (!top->drv || !base->drv) {
> > >> + assert(active);
> > >> + assert(top);
> > >> + /* Verify that top is in backing chain of active */
> > >> + bs = active;
> > >> + while (bs && bs != top) {
> > >> + bs = bs->backing_hd;
> > >> + }
> > >> + if (!bs) {
> > >> goto exit;
> > >> }
> > >> + /* Verify that base is in backing chain of top */
> > >> + if (base) {
> > >> + while (bs && bs != base) {
> > >> + bs = bs->backing_hd;
> > >> + }
> > >> + if (bs != base) {
> > >> + goto exit;
> > >> + }
> > >> + }
> > >>
> > >> - new_top_bs = bdrv_find_overlay(active, top);
> > >> -
> > >> - if (new_top_bs == NULL) {
> > >> - /* we could not find the image above 'top', this is an error */
> > >> + if (!top->drv || (base && !base->drv)) {
> > >> goto exit;
> > >> }
> > >> -
> > >> - /* special case of new_top_bs->backing_hd already pointing to base - nothing
> > >> - * to do, no intermediate images */
> > >> - if (new_top_bs->backing_hd == base) {
> > >> + if (top == base) {
> > >> + ret = 0;
> > >> + goto exit;
> > >> + } else if (top == active) {
> > >> + assert(base);
> > >> + drop_start = active->backing_hd;
> > >> + bdrv_swap(active, base);
> > >
> > > This will assert in block.c, in bdrv_swap, on the test for
> > > anonymity of active. (For testing, I changed the active layer commit
> > > in mirror to use bdrv_drop_intermediate()).
>
> Jeff, you're right, because bdrv_swap requires first argument to be a "new"
> BDS, while we are passing in an top BDS.
>
> But what happens if we write bdrv_swap(base, active)?
>
That seems like it could work - I did a quick test, and did not run
into any issues, going from active->base, and active->intermediate.
> > >
> > > Unfortunately, there are other problems as well (anonymity could be
> > > fixed by bdrv_make_anon(active)).
> > >
> > > Using line numbers from my version of block.c, lines 1957, 1959, and
> > > 1960 will each cause an assert (these lines are all in bdrv_swap()):
> > >
> > > 1956: /* bs_new must be anonymous and shouldn't have anything fancy
> > > enabled */
> > > 1957: assert(bs_new->device_name[0] == '\0');
> > > 1958: assert(QLIST_EMPTY(&bs_new->dirty_bitmaps));
> > > 1959: assert(bs_new->job == NULL);
> > > 1960: assert(bs_new->dev == NULL);
> > >
> > > Markus - on line 1960 above, is it safe to remove that check (and the
> > > other check further down in bdrv_swap())?
> >
> > I guess you mean the one under /* Check a few fields that should remain
> > attached to the device */ by "the other check".
> >
> > bdrv_swap() is a scary, scary function. It has a number of
> > preconditions, and we've tried to make them explicit in assertions.
> >
> > The preconditions could be:
> >
> > (0) Implicit. Or less politely said: unstated / unknown.
> >
> > (1) Explicit, but wrong.
> >
> > (2) Restrictions: the swapping code doesn't cover this state, but it
> > could be made to cover it, relaxing the precondition.
> >
> > (3) Fundamental: the precondition cannot or should not be relaxed.
> >
> > BDS member dev is is the back pointer for the device model property
> > pointing to the device model's backend. It must stay on top, and
> > bdrv_move_feature_fields() duly moves it, along with its buddies dev_ops
> > and dev_opaque. Obviously, only one of bdrv_old and bdrv_new can be on
> > top at the same time. bdrv_swap() currently assumes that bdrv_old is
> > the top one on entry. Feels like an instance of (3).
> >
> > > Thinking about it more, there may be other landmines in bdrv_swap()
> > > for this case; prior to this, bdrv_swap() was always called with
> > > bs_new being a newly-created BDS. With the active layer BDS it almost
> > > certainly is not 'new', and could have other "prohibited" fields set,
> > > in addition to the above (e.g. io limits, etc.)
> >
> > Hairy...
> >
> > We talked about splitting BlockBackend off BDS with an axe. Do you
> > think that would make this series less hairy?
>
> Hopefully, because it will help us to get rid of bdrv_move_feature_fields. :)
>
> But if we need to get rid of bdrv_swap, we need a generic "level of indirect"
> between BDS and BDS user, so we don't need to worry about the validity of old
> BDS pointers when we update the chain. Just like BlockBackend does at device
> emulation side. That's an even bigger project.
>
> Thanks,
> Fam
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 06/14] block: Add backing_blocker in BlockDriverState
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 06/14] block: Add backing_blocker in BlockDriverState Fam Zheng
2014-04-07 0:31 ` Jeff Cody
@ 2014-04-09 18:29 ` Jeff Cody
2014-04-10 2:36 ` Fam Zheng
1 sibling, 1 reply; 36+ messages in thread
From: Jeff Cody @ 2014-04-09 18:29 UTC (permalink / raw)
To: Fam Zheng
Cc: kwolf, benoit.canet, rjones, armbru, qemu-devel, ptoscano, imain,
stefanha, pbonzini
On Mon, Mar 10, 2014 at 03:26:02PM +0800, Fam Zheng wrote:
> This makes use of op_blocker and blocks all the operations except for
> commit target, on each BlockDriverState->backing_hd.
>
> The asserts for op_blocker in bdrv_swap are removed because with this
> change, the target of block commit has at least the backing blocker of
> its child, so the assertion is not true. Callers should do their check.
>
> Signed-off-by: Fam Zheng <famz@redhat.com>
> ---
> block.c | 24 ++++++++++++++++++++----
> block/mirror.c | 1 +
> include/block/block_int.h | 3 +++
> 3 files changed, 24 insertions(+), 4 deletions(-)
>
> diff --git a/block.c b/block.c
> index 64738dc..95247c8 100644
> --- a/block.c
> +++ b/block.c
> @@ -1050,16 +1050,33 @@ fail:
> void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
> {
>
> + if (bs->backing_hd) {
> + assert(error_is_set(&bs->backing_blocker));
> + bdrv_op_unblock_all(bs->backing_hd, bs->backing_blocker);
> + } else if (backing_hd) {
> + error_setg(&bs->backing_blocker,
> + "device is used as backing hd of '%s'",
> + bs->device_name);
> + }
> +
> bs->backing_hd = backing_hd;
> if (!backing_hd) {
> bs->backing_file[0] = '\0';
> bs->backing_format[0] = '\0';
> + if (error_is_set(&bs->backing_blocker)) {
> + error_free(bs->backing_blocker);
> + }
> goto out;
> }
> bs->open_flags &= ~BDRV_O_NO_BACKING;
> pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename);
> pstrcpy(bs->backing_format, sizeof(bs->backing_format),
> backing_hd->drv ? backing_hd->drv->format_name : "");
> +
> + bdrv_op_block_all(bs->backing_hd, bs->backing_blocker);
> + /* Otherwise we won't be able to commit due to check in bdrv_commit */
> + bdrv_op_unblock(bs->backing_hd, BLOCK_OP_TYPE_COMMIT,
> + bs->backing_blocker);
> out:
> bdrv_refresh_limits(bs);
> }
> @@ -1699,8 +1716,9 @@ void bdrv_close(BlockDriverState *bs)
>
> if (bs->drv) {
> if (bs->backing_hd) {
> - bdrv_unref(bs->backing_hd);
> - bs->backing_hd = NULL;
> + BlockDriverState *backing_hd = bs->backing_hd;
> + bdrv_set_backing_hd(bs, NULL);
> + bdrv_unref(backing_hd);
> }
> bs->drv->bdrv_close(bs);
> g_free(bs->opaque);
> @@ -1908,7 +1926,6 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
> assert(QLIST_EMPTY(&bs_new->dirty_bitmaps));
> assert(bs_new->job == NULL);
> assert(bs_new->dev == NULL);
> - assert(bdrv_op_blocker_is_empty(bs_new));
> assert(bs_new->io_limits_enabled == false);
> assert(!throttle_have_timer(&bs_new->throttle_state));
>
> @@ -1927,7 +1944,6 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
> /* Check a few fields that should remain attached to the device */
> assert(bs_new->dev == NULL);
> assert(bs_new->job == NULL);
> - assert(bdrv_op_blocker_is_empty(bs_new));
> assert(bs_new->io_limits_enabled == false);
> assert(!throttle_have_timer(&bs_new->throttle_state));
>
> diff --git a/block/mirror.c b/block/mirror.c
> index dd5ee05..6dc84e8 100644
> --- a/block/mirror.c
> +++ b/block/mirror.c
> @@ -487,6 +487,7 @@ immediate_exit:
> * trigger the unref from the top one */
> BlockDriverState *p = s->base->backing_hd;
> s->base->backing_hd = NULL;
> + bdrv_op_unblock_all(p, s->base->backing_blocker);
> bdrv_unref(p);
FYI, this is what I changed in my testing, to try out the active layer
case in bdrv_drop_intermediate(). Since you'll need to respin anyway,
might as well clean this up to use the updated
bdrv_drop_intermediate():
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -490,15 +490,8 @@ immediate_exit:
if (bdrv_get_flags(s->target) != bdrv_get_flags(s->common.bs)) {
bdrv_reopen(s->target, bdrv_get_flags(s->common.bs), NULL);
}
- bdrv_swap(s->target, s->common.bs);
- if (s->common.driver->job_type == BLOCK_JOB_TYPE_COMMIT) {
- /* drop the bs loop chain formed by the swap: break the loop then
- * trigger the unref from the top one */
- BlockDriverState *p = s->base->backing_hd;
- s->base->backing_hd = NULL;
- bdrv_op_unblock_all(p, s->base->backing_blocker);
- bdrv_unref(p);
- }
+ bdrv_op_unblock_all(s->common.bs->backing_hd, s->common.bs->backing_blocker);
+ bdrv_drop_intermediate(s->common.bs, s->common.bs, s->target);
}
bdrv_unref(s->target);
block_job_completed(&s->common, ret);
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 12/14] block: Add blockdev-backup to transaction
2014-04-07 21:11 ` Eric Blake
@ 2014-04-10 2:15 ` Fam Zheng
0 siblings, 0 replies; 36+ messages in thread
From: Fam Zheng @ 2014-04-10 2:15 UTC (permalink / raw)
To: Eric Blake
Cc: kwolf, benoit.canet, rjones, jcody, qemu-devel, armbru, imain,
stefanha, pbonzini, ptoscano
On Mon, 04/07 15:11, Eric Blake wrote:
> On 03/10/2014 01:26 AM, Fam Zheng wrote:
> > Signed-off-by: Fam Zheng <famz@redhat.com>
> > ---
> > blockdev.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
> > qapi-schema.json | 1 +
> > 2 files changed, 49 insertions(+)
> >
>
> > +++ b/qapi-schema.json
> > @@ -1972,6 +1972,7 @@
> > 'data': {
> > 'blockdev-snapshot-sync': 'BlockdevSnapshot',
> > 'drive-backup': 'DriveBackup',
> > + 'blockdev-backup': 'BlockdevBackup',
> > 'abort': 'Abort',
> > 'blockdev-snapshot-internal-sync': 'BlockdevSnapshotInternal'
> > } }
>
> It might be nice to mention that the union was expanded in 2.1;
> something like:
>
> # A discriminated record of operations that can be performed with
> # @transaction.
> #
> # Since 1.1, blockdev-backup since 2.1
> ##
> { 'union': 'TransactionAction',
>
> Of course, this is a pre-existing problem, as we've added other actions
> since 1.1 (blockdev-snapshot-internal-sync in 1.7, for example), so it
> could be justified as a separate patch. But it can't hurt to start
> being more thorough in our docs.
>
OK, I'll add this to comment.
Thanks,
Fam
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [Qemu-devel] [PATCH v17 06/14] block: Add backing_blocker in BlockDriverState
2014-04-09 18:29 ` Jeff Cody
@ 2014-04-10 2:36 ` Fam Zheng
0 siblings, 0 replies; 36+ messages in thread
From: Fam Zheng @ 2014-04-10 2:36 UTC (permalink / raw)
To: Jeff Cody
Cc: kwolf, benoit.canet, rjones, armbru, qemu-devel, ptoscano, imain,
stefanha, pbonzini
On Wed, 04/09 14:29, Jeff Cody wrote:
> On Mon, Mar 10, 2014 at 03:26:02PM +0800, Fam Zheng wrote:
> > This makes use of op_blocker and blocks all the operations except for
> > commit target, on each BlockDriverState->backing_hd.
> >
> > The asserts for op_blocker in bdrv_swap are removed because with this
> > change, the target of block commit has at least the backing blocker of
> > its child, so the assertion is not true. Callers should do their check.
> >
> > Signed-off-by: Fam Zheng <famz@redhat.com>
> > ---
> > block.c | 24 ++++++++++++++++++++----
> > block/mirror.c | 1 +
> > include/block/block_int.h | 3 +++
> > 3 files changed, 24 insertions(+), 4 deletions(-)
> >
> > diff --git a/block.c b/block.c
> > index 64738dc..95247c8 100644
> > --- a/block.c
> > +++ b/block.c
> > @@ -1050,16 +1050,33 @@ fail:
> > void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
> > {
> >
> > + if (bs->backing_hd) {
> > + assert(error_is_set(&bs->backing_blocker));
> > + bdrv_op_unblock_all(bs->backing_hd, bs->backing_blocker);
> > + } else if (backing_hd) {
> > + error_setg(&bs->backing_blocker,
> > + "device is used as backing hd of '%s'",
> > + bs->device_name);
> > + }
> > +
> > bs->backing_hd = backing_hd;
> > if (!backing_hd) {
> > bs->backing_file[0] = '\0';
> > bs->backing_format[0] = '\0';
> > + if (error_is_set(&bs->backing_blocker)) {
> > + error_free(bs->backing_blocker);
> > + }
> > goto out;
> > }
> > bs->open_flags &= ~BDRV_O_NO_BACKING;
> > pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename);
> > pstrcpy(bs->backing_format, sizeof(bs->backing_format),
> > backing_hd->drv ? backing_hd->drv->format_name : "");
> > +
> > + bdrv_op_block_all(bs->backing_hd, bs->backing_blocker);
> > + /* Otherwise we won't be able to commit due to check in bdrv_commit */
> > + bdrv_op_unblock(bs->backing_hd, BLOCK_OP_TYPE_COMMIT,
> > + bs->backing_blocker);
> > out:
> > bdrv_refresh_limits(bs);
> > }
> > @@ -1699,8 +1716,9 @@ void bdrv_close(BlockDriverState *bs)
> >
> > if (bs->drv) {
> > if (bs->backing_hd) {
> > - bdrv_unref(bs->backing_hd);
> > - bs->backing_hd = NULL;
> > + BlockDriverState *backing_hd = bs->backing_hd;
> > + bdrv_set_backing_hd(bs, NULL);
> > + bdrv_unref(backing_hd);
> > }
> > bs->drv->bdrv_close(bs);
> > g_free(bs->opaque);
> > @@ -1908,7 +1926,6 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
> > assert(QLIST_EMPTY(&bs_new->dirty_bitmaps));
> > assert(bs_new->job == NULL);
> > assert(bs_new->dev == NULL);
> > - assert(bdrv_op_blocker_is_empty(bs_new));
> > assert(bs_new->io_limits_enabled == false);
> > assert(!throttle_have_timer(&bs_new->throttle_state));
> >
> > @@ -1927,7 +1944,6 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
> > /* Check a few fields that should remain attached to the device */
> > assert(bs_new->dev == NULL);
> > assert(bs_new->job == NULL);
> > - assert(bdrv_op_blocker_is_empty(bs_new));
> > assert(bs_new->io_limits_enabled == false);
> > assert(!throttle_have_timer(&bs_new->throttle_state));
> >
> > diff --git a/block/mirror.c b/block/mirror.c
> > index dd5ee05..6dc84e8 100644
> > --- a/block/mirror.c
> > +++ b/block/mirror.c
> > @@ -487,6 +487,7 @@ immediate_exit:
> > * trigger the unref from the top one */
> > BlockDriverState *p = s->base->backing_hd;
> > s->base->backing_hd = NULL;
> > + bdrv_op_unblock_all(p, s->base->backing_blocker);
> > bdrv_unref(p);
>
> FYI, this is what I changed in my testing, to try out the active layer
> case in bdrv_drop_intermediate(). Since you'll need to respin anyway,
> might as well clean this up to use the updated
> bdrv_drop_intermediate():
Good idea!
However bdrv_drop_intermediate() doesn't work for mirror job, because they are
not in the same backing chain. So we need an "if" here.
Will adjust this patch and add it in respin.
Thanks,
Fam
>
>
> --- a/block/mirror.c
> +++ b/block/mirror.c
> @@ -490,15 +490,8 @@ immediate_exit:
> if (bdrv_get_flags(s->target) != bdrv_get_flags(s->common.bs)) {
> bdrv_reopen(s->target, bdrv_get_flags(s->common.bs), NULL);
> }
> - bdrv_swap(s->target, s->common.bs);
> - if (s->common.driver->job_type == BLOCK_JOB_TYPE_COMMIT) {
> - /* drop the bs loop chain formed by the swap: break the loop then
> - * trigger the unref from the top one */
> - BlockDriverState *p = s->base->backing_hd;
> - s->base->backing_hd = NULL;
> - bdrv_op_unblock_all(p, s->base->backing_blocker);
> - bdrv_unref(p);
> - }
> + bdrv_op_unblock_all(s->common.bs->backing_hd, s->common.bs->backing_blocker);
> + bdrv_drop_intermediate(s->common.bs, s->common.bs, s->target);
> }
> bdrv_unref(s->target);
> block_job_completed(&s->common, ret);
^ permalink raw reply [flat|nested] 36+ messages in thread
end of thread, other threads:[~2014-04-10 2:36 UTC | newest]
Thread overview: 36+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2014-03-10 7:25 [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
2014-03-10 7:25 ` [Qemu-devel] [PATCH v17 01/14] block: Add BlockOpType enum Fam Zheng
2014-04-06 23:47 ` Jeff Cody
2014-03-10 7:25 ` [Qemu-devel] [PATCH v17 02/14] block: Introduce op_blockers to BlockDriverState Fam Zheng
2014-04-06 23:49 ` Jeff Cody
2014-04-08 6:56 ` Fam Zheng
2014-03-10 7:25 ` [Qemu-devel] [PATCH v17 03/14] block: Replace in_use with operation blocker Fam Zheng
2014-04-07 0:10 ` Jeff Cody
2014-04-07 0:24 ` Jeff Cody
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 04/14] block: Move op_blocker check from block_job_create to its caller Fam Zheng
2014-04-06 23:50 ` Jeff Cody
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 05/14] block: Add bdrv_set_backing_hd() Fam Zheng
2014-04-07 0:01 ` Jeff Cody
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 06/14] block: Add backing_blocker in BlockDriverState Fam Zheng
2014-04-07 0:31 ` Jeff Cody
2014-04-08 7:37 ` Fam Zheng
2014-04-09 18:29 ` Jeff Cody
2014-04-10 2:36 ` Fam Zheng
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 07/14] block: Parse "backing" option to reference existing BDS Fam Zheng
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 08/14] block: Support dropping active in bdrv_drop_intermediate Fam Zheng
2014-04-07 18:47 ` Jeff Cody
2014-04-08 8:15 ` Markus Armbruster
2014-04-08 9:07 ` Fam Zheng
2014-04-09 18:12 ` Jeff Cody
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 09/14] stream: Use bdrv_drop_intermediate and drop close_unused_images Fam Zheng
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 10/14] qmp: Add command 'blockdev-backup' Fam Zheng
2014-04-07 21:07 ` Eric Blake
2014-04-08 7:00 ` Fam Zheng
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 11/14] block: Allow backup on referenced named BlockDriverState Fam Zheng
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 12/14] block: Add blockdev-backup to transaction Fam Zheng
2014-04-07 21:11 ` Eric Blake
2014-04-10 2:15 ` Fam Zheng
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 13/14] qemu-iotests: Test blockdev-backup in 055 Fam Zheng
2014-03-10 7:26 ` [Qemu-devel] [PATCH v17 14/14] qemu-iotests: Image fleecing test case 083 Fam Zheng
2014-04-02 6:01 ` [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD Fam Zheng
2014-04-03 1:53 ` Jeff Cody
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