* [Qemu-devel] [PATCH v4 01/20] docs: incremental backup documentation
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
@ 2015-03-20 19:16 ` John Snow
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 02/20] qapi: Add optional field "name" to block dirty bitmap John Snow
` (20 subsequent siblings)
21 siblings, 0 replies; 54+ messages in thread
From: John Snow @ 2015-03-20 19:16 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
---
docs/bitmaps.md | 311 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 311 insertions(+)
create mode 100644 docs/bitmaps.md
diff --git a/docs/bitmaps.md b/docs/bitmaps.md
new file mode 100644
index 0000000..ad8c33b
--- /dev/null
+++ b/docs/bitmaps.md
@@ -0,0 +1,311 @@
+# Dirty Bitmaps and Incremental Backup
+
+* Dirty Bitmaps are objects that track which data needs to be backed up for the
+ next incremental backup.
+
+* Dirty bitmaps can be created at any time and attached to any node
+ (not just complete drives.)
+
+## Dirty Bitmap Names
+
+* A dirty bitmap's name is unique to the node, but bitmaps attached to different
+nodes can share the same name.
+
+## Bitmap Modes
+
+* A Bitmap can be "frozen," which means that it is currently in-use by a backup
+operation and cannot be deleted, renamed, written to, reset,
+etc.
+
+## Basic QMP Usage
+
+### Supported Commands ###
+
+* block-dirty-bitmap-add
+* block-dirty-bitmap-remove
+* block-dirty-bitmap-clear
+
+### Creation
+
+* To create a new bitmap, enabled, on the drive with id=drive0:
+
+```json
+{ "execute": "block-dirty-bitmap-add",
+ "arguments": {
+ "node": "drive0",
+ "name": "bitmap0"
+ }
+}
+```
+
+* This bitmap will have a default granularity that matches the cluster size of
+its associated drive, if available, clamped to between [4KiB, 64KiB].
+The current default for qcow2 is 64KiB.
+
+* To create a new bitmap that tracks changes in 32KiB segments:
+
+```json
+{ "execute": "block-dirty-bitmap-add",
+ "arguments": {
+ "node": "drive0",
+ "name": "bitmap0",
+ "granularity": 32768
+ }
+}
+```
+
+### Deletion
+
+* Can be performed on a disabled bitmap, but not a frozen one.
+
+* Because bitmaps are only unique to the node to which they are attached,
+you must specify the node/drive name here, too.
+
+```json
+{ "execute": "block-dirty-bitmap-remove",
+ "arguments": {
+ "node": "drive0",
+ "name": "bitmap0"
+ }
+}
+```
+
+### Resetting
+
+* Resetting a bitmap will clear all information it holds.
+* An incremental backup created from an empty bitmap will copy no data,
+as if nothing has changed.
+
+```json
+{ "execute": "block-dirty-bitmap-clear",
+ "arguments": {
+ "node": "drive0",
+ "name": "bitmap0"
+ }
+}
+```
+
+## Transactions (Not yet implemented)
+
+* Transactional commands are forthcoming in a future version,
+ and are not yet available for use. This section serves as
+ documentation of intent for their design and usage.
+
+### Justification
+Bitmaps can be safely modified when the VM is paused or halted by using
+the basic QMP commands. For instance, you might perform the following actions:
+
+1. Boot the VM in a paused state.
+2. Create a full drive backup of drive0.
+3. Create a new bitmap attached to drive0.
+4. Resume execution of the VM.
+5. Incremental backups are ready to be created.
+
+At this point, the bitmap and drive backup would be correctly in sync,
+and incremental backups made from this point forward would be correctly aligned
+to the full drive backup.
+
+This is not particularly useful if we decide we want to start incremental
+backups after the VM has been running for a while, for which we will need to
+perform actions such as the following:
+
+1. Boot the VM and begin execution.
+2. Using a single transaction, perform the following operations:
+ * Create bitmap0.
+ * Create a full drive backup of drive0.
+3. Incremental backups are now ready to be created.
+
+### Supported Bitmap Transactions
+
+* block-dirty-bitmap-add
+* block-dirty-bitmap-clear
+
+The usages are identical to their respective QMP commands, but see below
+for examples.
+
+### Example: New Incremental Backup
+
+As outlined in the justification, perhaps we want to create a new incremental
+backup chain attached to a drive.
+
+```json
+{ "execute": "transaction",
+ "arguments": {
+ "actions": [
+ {"type": "block-dirty-bitmap-add",
+ "data": {"node": "drive0", "name": "bitmap0"} },
+ {"type": "drive-backup",
+ "data": {"device": "drive0", "target": "/path/to/full_backup.img",
+ "sync": "full", "format": "qcow2"} }
+ ]
+ }
+}
+```
+
+### Example: New Incremental Backup Anchor Point
+
+Maybe we just want to create a new full backup with an existing bitmap and
+want to reset the bitmap to track the new chain.
+
+```json
+{ "execute": "transaction",
+ "arguments": {
+ "actions": [
+ {"type": "block-dirty-bitmap-clear",
+ "data": {"node": "drive0", "name": "bitmap0"} },
+ {"type": "drive-backup",
+ "data": {"device": "drive0", "target": "/path/to/new_full_backup.img",
+ "sync": "full", "format": "qcow2"} }
+ ]
+ }
+}
+```
+
+## Incremental Backups
+
+The star of the show.
+
+**Nota Bene!** Only incremental backups of entire drives are supported for now.
+So despite the fact that you can attach a bitmap to any arbitrary node, they are
+only currently useful when attached to the root node. This is because
+drive-backup only supports drives/devices instead of arbitrary nodes.
+
+### Example: First Incremental Backup
+
+1. Create a full backup and sync it to the dirty bitmap, as in the transactional
+examples above; or with the VM offline, manually create a full copy and then
+create a new bitmap before the VM begins execution.
+
+ * Let's assume the full backup is named 'full_backup.img'.
+ * Let's assume the bitmap you created is 'bitmap0' attached to 'drive0'.
+
+2. Create a destination image for the incremental backup that utilizes the
+full backup as a backing image.
+
+ * Let's assume it is named 'incremental.0.img'.
+
+ ```sh
+ # qemu-img create -f qcow2 incremental.0.img -b full_backup.img -F qcow2
+ ```
+
+3. Issue the incremental backup command:
+
+ ```json
+ { "execute": "drive-backup",
+ "arguments": {
+ "device": "drive0",
+ "bitmap": "bitmap0",
+ "target": "incremental.0.img",
+ "format": "qcow2",
+ "sync": "dirty-bitmap",
+ "mode": "existing"
+ }
+ }
+ ```
+
+### Example: Second Incremental Backup
+
+1. Create a new destination image for the incremental backup that points to the
+ previous one, e.g.: 'incremental.1.img'
+
+ ```sh
+ # qemu-img create -f qcow2 incremental.1.img -b incremental.0.img -F qcow2
+ ```
+
+2. Issue a new incremental backup command. The only difference here is that we
+ have changed the target image below.
+
+ ```json
+ { "execute": "drive-backup",
+ "arguments": {
+ "device": "drive0",
+ "bitmap": "bitmap0",
+ "target": "incremental.1.img",
+ "format": "qcow2",
+ "sync": "dirty-bitmap",
+ "mode": "existing"
+ }
+ }
+ ```
+
+## Errors
+
+* In the event of an error that occurs after a backup job is successfully
+ launched, either by a direct QMP command or a QMP transaction, the user
+ will receive a BLOCK_JOB_COMPLETE event with a failure message, accompanied
+ by a BLOCK_JOB_ERROR event.
+
+* In the case of an event being cancelled, the user will receive a
+ BLOCK_JOB_CANCELLED event instead of a pair of COMPLETE and ERROR events.
+
+* In either case, the incremental backup data contained within the bitmap is
+ safely rolled back, and the data within the bitmap is not lost. The image
+ file created for the failed attempt can be safely deleted.
+
+* Once the underlying problem is fixed (e.g. more storage space is freed up),
+ you can simply retry the incremental backup command with the same bitmap.
+
+### Example
+
+1. Create a target image:
+
+ ```sh
+ # qemu-img create -f qcow2 incremental.0.img -b full_backup.img -F qcow2
+ ```
+
+2. Attempt to create an incremental backup via QMP:
+
+ ```json
+ { "execute": "drive-backup",
+ "arguments": {
+ "device": "drive0",
+ "bitmap": "bitmap0",
+ "target": "incremental.0.img",
+ "format": "qcow2",
+ "sync": "dirty-bitmap",
+ "mode": "existing"
+ }
+ }
+ ```
+
+3. Receive an event notifying us of failure:
+
+ ```json
+ { "timestamp": { "seconds": 1424709442, "microseconds": 844524 },
+ "data": { "speed": 0, "offset": 0, "len": 67108864,
+ "error": "No space left on device",
+ "device": "drive1", "type": "backup" },
+ "event": "BLOCK_JOB_COMPLETED" }
+ ```
+
+4. Delete the failed incremental, and re-create the image.
+
+ ```sh
+ # rm incremental.0.img
+ # qemu-img create -f qcow2 incremental.0.img -b full_backup.img -F qcow2
+ ```
+
+5. Retry the command after fixing the underlaying problem,
+ such as freeing up space on the backup volume:
+
+ ```json
+ { "execute": "drive-backup",
+ "arguments": {
+ "device": "drive0",
+ "bitmap": "bitmap0",
+ "target": "incremental.0.img",
+ "format": "qcow2",
+ "sync": "dirty-bitmap",
+ "mode": "existing"
+ }
+ }
+ ```
+
+6. Receive confirmation that the job completed successfully:
+
+ ```json
+ { "timestamp": { "seconds": 1424709668, "microseconds": 526525 },
+ "data": { "device": "drive1", "type": "backup",
+ "speed": 0, "len": 67108864, "offset": 67108864},
+ "event": "BLOCK_JOB_COMPLETED" }
+ ```
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* [Qemu-devel] [PATCH v4 02/20] qapi: Add optional field "name" to block dirty bitmap
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 01/20] docs: incremental backup documentation John Snow
@ 2015-03-20 19:16 ` John Snow
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 03/20] qmp: Ensure consistent granularity type John Snow
` (19 subsequent siblings)
21 siblings, 0 replies; 54+ messages in thread
From: John Snow @ 2015-03-20 19:16 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
From: Fam Zheng <famz@redhat.com>
This field will be set for user created dirty bitmap. Also pass in an
error pointer to bdrv_create_dirty_bitmap, so when a name is already
taken on this BDS, it can report an error message. This is not global
check, two BDSes can have dirty bitmap with a common name.
Implemented bdrv_find_dirty_bitmap to find a dirty bitmap by name, will
be used later when other QMP commands want to reference dirty bitmap by
name.
Add bdrv_dirty_bitmap_make_anon. This unsets the name of dirty bitmap.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
---
block.c | 32 +++++++++++++++++++++++++++++++-
block/mirror.c | 2 +-
include/block/block.h | 7 ++++++-
migration/block.c | 2 +-
qapi/block-core.json | 4 +++-
5 files changed, 42 insertions(+), 5 deletions(-)
diff --git a/block.c b/block.c
index 0fe97de..bdf98a9 100644
--- a/block.c
+++ b/block.c
@@ -53,6 +53,7 @@
struct BdrvDirtyBitmap {
HBitmap *bitmap;
+ char *name;
QLIST_ENTRY(BdrvDirtyBitmap) list;
};
@@ -5402,7 +5403,28 @@ bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov)
return true;
}
-BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs, int granularity,
+BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs, const char *name)
+{
+ BdrvDirtyBitmap *bm;
+
+ assert(name);
+ QLIST_FOREACH(bm, &bs->dirty_bitmaps, list) {
+ if (bm->name && !strcmp(name, bm->name)) {
+ return bm;
+ }
+ }
+ return NULL;
+}
+
+void bdrv_dirty_bitmap_make_anon(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
+{
+ g_free(bitmap->name);
+ bitmap->name = NULL;
+}
+
+BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
+ int granularity,
+ const char *name,
Error **errp)
{
int64_t bitmap_size;
@@ -5410,6 +5432,10 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs, int granularity,
assert((granularity & (granularity - 1)) == 0);
+ if (name && bdrv_find_dirty_bitmap(bs, name)) {
+ error_setg(errp, "Bitmap already exists: %s", name);
+ return NULL;
+ }
granularity >>= BDRV_SECTOR_BITS;
assert(granularity);
bitmap_size = bdrv_nb_sectors(bs);
@@ -5420,6 +5446,7 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs, int granularity,
}
bitmap = g_new0(BdrvDirtyBitmap, 1);
bitmap->bitmap = hbitmap_alloc(bitmap_size, ffs(granularity) - 1);
+ bitmap->name = g_strdup(name);
QLIST_INSERT_HEAD(&bs->dirty_bitmaps, bitmap, list);
return bitmap;
}
@@ -5431,6 +5458,7 @@ void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
if (bm == bitmap) {
QLIST_REMOVE(bitmap, list);
hbitmap_free(bitmap->bitmap);
+ g_free(bitmap->name);
g_free(bitmap);
return;
}
@@ -5449,6 +5477,8 @@ BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs)
info->count = bdrv_get_dirty_count(bs, bm);
info->granularity =
((int64_t) BDRV_SECTOR_SIZE << hbitmap_granularity(bm->bitmap));
+ info->has_name = !!bm->name;
+ info->name = g_strdup(bm->name);
entry->value = info;
*plist = entry;
plist = &entry->next;
diff --git a/block/mirror.c b/block/mirror.c
index 4056164..f073ad7 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -703,7 +703,7 @@ static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target,
s->granularity = granularity;
s->buf_size = MAX(buf_size, granularity);
- s->dirty_bitmap = bdrv_create_dirty_bitmap(bs, granularity, errp);
+ s->dirty_bitmap = bdrv_create_dirty_bitmap(bs, granularity, NULL, errp);
if (!s->dirty_bitmap) {
return;
}
diff --git a/include/block/block.h b/include/block/block.h
index 4c57d63..05e32f9 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -449,8 +449,13 @@ bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov);
struct HBitmapIter;
typedef struct BdrvDirtyBitmap BdrvDirtyBitmap;
-BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs, int granularity,
+BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
+ int granularity,
+ const char *name,
Error **errp);
+BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs,
+ const char *name);
+void bdrv_dirty_bitmap_make_anon(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs);
int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, int64_t sector);
diff --git a/migration/block.c b/migration/block.c
index 085c0fa..02a7d26 100644
--- a/migration/block.c
+++ b/migration/block.c
@@ -320,7 +320,7 @@ static int set_dirty_tracking(void)
QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
bmds->dirty_bitmap = bdrv_create_dirty_bitmap(bmds->bs, BLOCK_SIZE,
- NULL);
+ NULL, NULL);
if (!bmds->dirty_bitmap) {
ret = -errno;
goto fail;
diff --git a/qapi/block-core.json b/qapi/block-core.json
index f525b04..ad3d5c3 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -330,6 +330,8 @@
#
# Block dirty bitmap information.
#
+# @name: #optional the name of the dirty bitmap (Since 2.4)
+#
# @count: number of dirty bytes according to the dirty bitmap
#
# @granularity: granularity of the dirty bitmap in bytes (since 1.4)
@@ -337,7 +339,7 @@
# Since: 1.3
##
{ 'type': 'BlockDirtyInfo',
- 'data': {'count': 'int', 'granularity': 'int'} }
+ 'data': {'*name': 'str', 'count': 'int', 'granularity': 'int'} }
##
# @BlockInfo:
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* [Qemu-devel] [PATCH v4 03/20] qmp: Ensure consistent granularity type
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 01/20] docs: incremental backup documentation John Snow
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 02/20] qapi: Add optional field "name" to block dirty bitmap John Snow
@ 2015-03-20 19:16 ` John Snow
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 04/20] qmp: Add block-dirty-bitmap-add and block-dirty-bitmap-remove John Snow
` (18 subsequent siblings)
21 siblings, 0 replies; 54+ messages in thread
From: John Snow @ 2015-03-20 19:16 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
We treat this field with a variety of different types everywhere
in the code. Now it's just uint32_t.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
---
block.c | 11 ++++++-----
block/mirror.c | 4 ++--
include/block/block.h | 2 +-
include/block/block_int.h | 2 +-
qapi/block-core.json | 2 +-
5 files changed, 11 insertions(+), 10 deletions(-)
diff --git a/block.c b/block.c
index bdf98a9..a05971a 100644
--- a/block.c
+++ b/block.c
@@ -5423,12 +5423,13 @@ void bdrv_dirty_bitmap_make_anon(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
}
BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
- int granularity,
+ uint32_t granularity,
const char *name,
Error **errp)
{
int64_t bitmap_size;
BdrvDirtyBitmap *bitmap;
+ uint32_t sector_granularity;
assert((granularity & (granularity - 1)) == 0);
@@ -5436,8 +5437,8 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
error_setg(errp, "Bitmap already exists: %s", name);
return NULL;
}
- granularity >>= BDRV_SECTOR_BITS;
- assert(granularity);
+ sector_granularity = granularity >> BDRV_SECTOR_BITS;
+ assert(sector_granularity);
bitmap_size = bdrv_nb_sectors(bs);
if (bitmap_size < 0) {
error_setg_errno(errp, -bitmap_size, "could not get length of device");
@@ -5445,7 +5446,7 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
return NULL;
}
bitmap = g_new0(BdrvDirtyBitmap, 1);
- bitmap->bitmap = hbitmap_alloc(bitmap_size, ffs(granularity) - 1);
+ bitmap->bitmap = hbitmap_alloc(bitmap_size, ffs(sector_granularity) - 1);
bitmap->name = g_strdup(name);
QLIST_INSERT_HEAD(&bs->dirty_bitmaps, bitmap, list);
return bitmap;
@@ -5476,7 +5477,7 @@ BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs)
BlockDirtyInfoList *entry = g_new0(BlockDirtyInfoList, 1);
info->count = bdrv_get_dirty_count(bs, bm);
info->granularity =
- ((int64_t) BDRV_SECTOR_SIZE << hbitmap_granularity(bm->bitmap));
+ ((uint32_t) BDRV_SECTOR_SIZE << hbitmap_granularity(bm->bitmap));
info->has_name = !!bm->name;
info->name = g_strdup(bm->name);
entry->value = info;
diff --git a/block/mirror.c b/block/mirror.c
index f073ad7..f8aac33 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -656,7 +656,7 @@ static const BlockJobDriver commit_active_job_driver = {
static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target,
const char *replaces,
- int64_t speed, int64_t granularity,
+ int64_t speed, uint32_t granularity,
int64_t buf_size,
BlockdevOnError on_source_error,
BlockdevOnError on_target_error,
@@ -717,7 +717,7 @@ static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target,
void mirror_start(BlockDriverState *bs, BlockDriverState *target,
const char *replaces,
- int64_t speed, int64_t granularity, int64_t buf_size,
+ int64_t speed, uint32_t granularity, int64_t buf_size,
MirrorSyncMode mode, BlockdevOnError on_source_error,
BlockdevOnError on_target_error,
BlockCompletionFunc *cb,
diff --git a/include/block/block.h b/include/block/block.h
index 05e32f9..5235086 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -450,7 +450,7 @@ bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov);
struct HBitmapIter;
typedef struct BdrvDirtyBitmap BdrvDirtyBitmap;
BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
- int granularity,
+ uint32_t granularity,
const char *name,
Error **errp);
BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs,
diff --git a/include/block/block_int.h b/include/block/block_int.h
index dccb092..fb9e100 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -590,7 +590,7 @@ void commit_active_start(BlockDriverState *bs, BlockDriverState *base,
*/
void mirror_start(BlockDriverState *bs, BlockDriverState *target,
const char *replaces,
- int64_t speed, int64_t granularity, int64_t buf_size,
+ int64_t speed, uint32_t granularity, int64_t buf_size,
MirrorSyncMode mode, BlockdevOnError on_source_error,
BlockdevOnError on_target_error,
BlockCompletionFunc *cb,
diff --git a/qapi/block-core.json b/qapi/block-core.json
index ad3d5c3..42c9d75 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -339,7 +339,7 @@
# Since: 1.3
##
{ 'type': 'BlockDirtyInfo',
- 'data': {'*name': 'str', 'count': 'int', 'granularity': 'int'} }
+ 'data': {'*name': 'str', 'count': 'int', 'granularity': 'uint32'} }
##
# @BlockInfo:
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* [Qemu-devel] [PATCH v4 04/20] qmp: Add block-dirty-bitmap-add and block-dirty-bitmap-remove
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (2 preceding siblings ...)
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 03/20] qmp: Ensure consistent granularity type John Snow
@ 2015-03-20 19:16 ` John Snow
2015-03-20 19:39 ` Max Reitz
2015-04-02 9:57 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 05/20] block: Introduce bdrv_dirty_bitmap_granularity() John Snow
` (17 subsequent siblings)
21 siblings, 2 replies; 54+ messages in thread
From: John Snow @ 2015-03-20 19:16 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
The new command pair is added to manage a user created dirty bitmap. The
dirty bitmap's name is mandatory and must be unique for the same device,
but different devices can have bitmaps with the same names.
The granularity is an optional field. If it is not specified, we will
choose a default granularity based on the cluster size if available,
clamped to between 4K and 64K to mirror how the 'mirror' code was
already choosing granularity. If we do not have cluster size info
available, we choose 64K. This code has been factored out into a helper
shared with block/mirror.
This patch also introduces the 'block_dirty_bitmap_lookup' helper,
which takes a device name and a dirty bitmap name and validates the
lookup, returning NULL and setting errp if there is a problem with
either field. This helper will be re-used in future patches in this
series.
The types added to block-core.json will be re-used in future patches
in this series, see:
'qapi: Add transaction support to block-dirty-bitmap-{add, enable, disable}'
Signed-off-by: John Snow <jsnow@redhat.com>
---
block.c | 20 +++++++++
block/mirror.c | 10 +----
blockdev.c | 117 ++++++++++++++++++++++++++++++++++++++++++++++++++
include/block/block.h | 1 +
qapi/block-core.json | 55 ++++++++++++++++++++++++
qmp-commands.hx | 56 ++++++++++++++++++++++++
6 files changed, 250 insertions(+), 9 deletions(-)
diff --git a/block.c b/block.c
index a05971a..c5d68ff 100644
--- a/block.c
+++ b/block.c
@@ -5497,6 +5497,26 @@ int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, int64_t sector
}
}
+/**
+ * Chooses a default granularity based on the existing cluster size,
+ * but clamped between [4K, 64K]. Defaults to 64K in the case that there
+ * is no cluster size information available.
+ */
+uint32_t bdrv_get_default_bitmap_granularity(BlockDriverState *bs)
+{
+ BlockDriverInfo bdi;
+ uint32_t granularity;
+
+ if (bdrv_get_info(bs, &bdi) >= 0 && bdi.cluster_size > 0) {
+ granularity = MAX(4096, bdi.cluster_size);
+ granularity = MIN(65536, granularity);
+ } else {
+ granularity = 65536;
+ }
+
+ return granularity;
+}
+
void bdrv_dirty_iter_init(BlockDriverState *bs,
BdrvDirtyBitmap *bitmap, HBitmapIter *hbi)
{
diff --git a/block/mirror.c b/block/mirror.c
index f8aac33..1cb700e 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -668,15 +668,7 @@ static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target,
MirrorBlockJob *s;
if (granularity == 0) {
- /* Choose the default granularity based on the target file's cluster
- * size, clamped between 4k and 64k. */
- BlockDriverInfo bdi;
- if (bdrv_get_info(target, &bdi) >= 0 && bdi.cluster_size != 0) {
- granularity = MAX(4096, bdi.cluster_size);
- granularity = MIN(65536, granularity);
- } else {
- granularity = 65536;
- }
+ granularity = bdrv_get_default_bitmap_granularity(target);
}
assert ((granularity & (granularity - 1)) == 0);
diff --git a/blockdev.c b/blockdev.c
index fbb3a79..7d71b81 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1164,6 +1164,68 @@ out_aio_context:
return NULL;
}
+/**
+ * block_dirty_bitmap_lookup:
+ * Return a dirty bitmap (if present), after validating
+ * the node reference and bitmap names.
+ *
+ * @node: The name of the BDS node to search for bitmaps
+ * @name: The name of the bitmap to search for
+ * @pbs: Output pointer for BDS lookup, if desired. Can be NULL.
+ * @paio: Output pointer for aio_context acquisition, if desired. Can be NULL.
+ * @errp: Output pointer for error information. Can be NULL.
+ *
+ * @return: A bitmap object on success, or NULL on failure.
+ */
+static BdrvDirtyBitmap *block_dirty_bitmap_lookup(const char *node,
+ const char *name,
+ BlockDriverState **pbs,
+ AioContext **paio,
+ Error **errp)
+{
+ BlockDriverState *bs;
+ BdrvDirtyBitmap *bitmap;
+ AioContext *aio_context;
+
+ if (!node) {
+ error_setg(errp, "Node cannot be NULL");
+ return NULL;
+ }
+ if (!name) {
+ error_setg(errp, "Bitmap name cannot be NULL");
+ return NULL;
+ }
+ bs = bdrv_lookup_bs(node, node, NULL);
+ if (!bs) {
+ error_setg(errp, "Node '%s' not found", node);
+ return NULL;
+ }
+
+ aio_context = bdrv_get_aio_context(bs);
+ aio_context_acquire(aio_context);
+
+ bitmap = bdrv_find_dirty_bitmap(bs, name);
+ if (!bitmap) {
+ error_setg(errp, "Dirty bitmap '%s' not found", name);
+ goto fail;
+ }
+
+ if (pbs) {
+ *pbs = bs;
+ }
+ if (paio) {
+ *paio = aio_context;
+ } else {
+ aio_context_release(aio_context);
+ }
+
+ return bitmap;
+
+ fail:
+ aio_context_release(aio_context);
+ return NULL;
+}
+
/* New and old BlockDriverState structs for atomic group operations */
typedef struct BlkTransactionState BlkTransactionState;
@@ -1953,6 +2015,61 @@ void qmp_block_set_io_throttle(const char *device, int64_t bps, int64_t bps_rd,
aio_context_release(aio_context);
}
+void qmp_block_dirty_bitmap_add(const char *node, const char *name,
+ bool has_granularity, uint32_t granularity,
+ Error **errp)
+{
+ AioContext *aio_context;
+ BlockDriverState *bs;
+
+ if (!name || name[0] == '\0') {
+ error_setg(errp, "Bitmap name cannot be empty");
+ return;
+ }
+
+ bs = bdrv_lookup_bs(node, node, errp);
+ if (!bs) {
+ return;
+ }
+
+ aio_context = bdrv_get_aio_context(bs);
+ aio_context_acquire(aio_context);
+
+ if (has_granularity) {
+ if (granularity < 512 || !is_power_of_2(granularity)) {
+ error_setg(errp, "Granularity must be power of 2 "
+ "and at least 512");
+ goto out;
+ }
+ } else {
+ /* Default to cluster size, if available: */
+ granularity = bdrv_get_default_bitmap_granularity(bs);
+ }
+
+ bdrv_create_dirty_bitmap(bs, granularity, name, errp);
+
+ out:
+ aio_context_release(aio_context);
+}
+
+void qmp_block_dirty_bitmap_remove(const char *node, const char *name,
+ Error **errp)
+{
+ AioContext *aio_context;
+ BlockDriverState *bs;
+ BdrvDirtyBitmap *bitmap;
+
+ bitmap = block_dirty_bitmap_lookup(node, name, &bs, &aio_context, errp);
+ if (!bitmap || !bs) {
+ return;
+ }
+
+ bdrv_dirty_bitmap_make_anon(bs, bitmap);
+ bdrv_release_dirty_bitmap(bs, bitmap);
+
+ aio_context_release(aio_context);
+}
+
int hmp_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data)
{
const char *id = qdict_get_str(qdict, "id");
diff --git a/include/block/block.h b/include/block/block.h
index 5235086..0f014a3 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -458,6 +458,7 @@ BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs,
void bdrv_dirty_bitmap_make_anon(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs);
+uint32_t bdrv_get_default_bitmap_granularity(BlockDriverState *bs);
int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, int64_t sector);
void bdrv_set_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int nr_sectors);
diff --git a/qapi/block-core.json b/qapi/block-core.json
index 42c9d75..faadd10 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -960,6 +960,61 @@
'*on-target-error': 'BlockdevOnError' } }
##
+# @BlockDirtyBitmap
+#
+# @node: name of device/node which the bitmap is tracking
+#
+# @name: name of the dirty bitmap
+#
+# Since 2.4
+##
+{ 'type': 'BlockDirtyBitmap',
+ 'data': { 'node': 'str', 'name': 'str' } }
+
+##
+# @BlockDirtyBitmapAdd
+#
+# @node: name of device/node which the bitmap is tracking
+#
+# @name: name of the dirty bitmap
+#
+# @granularity: #optional the bitmap granularity, default is 64k for
+# block-dirty-bitmap-add
+#
+# Since 2.4
+##
+{ 'type': 'BlockDirtyBitmapAdd',
+ 'data': { 'node': 'str', 'name': 'str', '*granularity': 'uint32' } }
+
+##
+# @block-dirty-bitmap-add
+#
+# Create a dirty bitmap with a name on the node
+#
+# Returns: nothing on success
+# If @node is not a valid block device or node, DeviceNotFound
+# If @name is already taken, GenericError with an explanation
+#
+# Since 2.4
+##
+{ 'command': 'block-dirty-bitmap-add',
+ 'data': 'BlockDirtyBitmapAdd' }
+
+##
+# @block-dirty-bitmap-remove
+#
+# Remove a dirty bitmap on the node
+#
+# Returns: nothing on success
+# If @node is not a valid block device or node, DeviceNotFound
+# If @name is not found, GenericError with an explanation
+#
+# Since 2.4
+##
+{ 'command': 'block-dirty-bitmap-remove',
+ 'data': 'BlockDirtyBitmap' }
+
+##
# @block_set_io_throttle:
#
# Change I/O throttle limits for a block drive.
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 7f68760..e9f2eb1 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -1270,6 +1270,62 @@ Example:
EQMP
{
+ .name = "block-dirty-bitmap-add",
+ .args_type = "node:B,name:s,granularity:i?",
+ .mhandler.cmd_new = qmp_marshal_input_block_dirty_bitmap_add,
+ },
+
+SQMP
+
+block-dirty-bitmap-add
+----------------------
+Since 2.4
+
+Create a dirty bitmap with a name on the device, and start tracking the writes.
+
+Arguments:
+
+- "node": device/node on which to create dirty bitmap (json-string)
+- "name": name of the new dirty bitmap (json-string)
+- "granularity": granularity to track writes with (int, optional)
+
+Example:
+
+-> { "execute": "block-dirty-bitmap-add", "arguments": { "node": "drive0",
+ "name": "bitmap0" } }
+<- { "return": {} }
+
+EQMP
+
+ {
+ .name = "block-dirty-bitmap-remove",
+ .args_type = "node:B,name:s",
+ .mhandler.cmd_new = qmp_marshal_input_block_dirty_bitmap_remove,
+ },
+
+SQMP
+
+block-dirty-bitmap-remove
+-------------------------
+Since 2.4
+
+Stop write tracking and remove the dirty bitmap that was created with
+block-dirty-bitmap-add.
+
+Arguments:
+
+- "node": device/node on which to remove dirty bitmap (json-string)
+- "name": name of the dirty bitmap to remove (json-string)
+
+Example:
+
+-> { "execute": "block-dirty-bitmap-remove", "arguments": { "node": "drive0",
+ "name": "bitmap0" } }
+<- { "return": {} }
+
+EQMP
+
+ {
.name = "blockdev-snapshot-sync",
.args_type = "device:s?,node-name:s?,snapshot-file:s,snapshot-node-name:s?,format:s?,mode:s?",
.mhandler.cmd_new = qmp_marshal_input_blockdev_snapshot_sync,
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [PATCH v4 04/20] qmp: Add block-dirty-bitmap-add and block-dirty-bitmap-remove
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 04/20] qmp: Add block-dirty-bitmap-add and block-dirty-bitmap-remove John Snow
@ 2015-03-20 19:39 ` Max Reitz
2015-04-02 9:57 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
1 sibling, 0 replies; 54+ messages in thread
From: Max Reitz @ 2015-03-20 19:39 UTC (permalink / raw)
To: John Snow, qemu-block
Cc: kwolf, famz, qemu-devel, armbru, vsementsov, stefanha
On 2015-03-20 at 15:16, John Snow wrote:
> The new command pair is added to manage a user created dirty bitmap. The
> dirty bitmap's name is mandatory and must be unique for the same device,
> but different devices can have bitmaps with the same names.
>
> The granularity is an optional field. If it is not specified, we will
> choose a default granularity based on the cluster size if available,
> clamped to between 4K and 64K to mirror how the 'mirror' code was
> already choosing granularity. If we do not have cluster size info
> available, we choose 64K. This code has been factored out into a helper
> shared with block/mirror.
>
> This patch also introduces the 'block_dirty_bitmap_lookup' helper,
> which takes a device name and a dirty bitmap name and validates the
> lookup, returning NULL and setting errp if there is a problem with
> either field. This helper will be re-used in future patches in this
> series.
>
> The types added to block-core.json will be re-used in future patches
> in this series, see:
> 'qapi: Add transaction support to block-dirty-bitmap-{add, enable, disable}'
>
> Signed-off-by: John Snow <jsnow@redhat.com>
> ---
> block.c | 20 +++++++++
> block/mirror.c | 10 +----
> blockdev.c | 117 ++++++++++++++++++++++++++++++++++++++++++++++++++
> include/block/block.h | 1 +
> qapi/block-core.json | 55 ++++++++++++++++++++++++
> qmp-commands.hx | 56 ++++++++++++++++++++++++
> 6 files changed, 250 insertions(+), 9 deletions(-)
>
> diff --git a/block.c b/block.c
> index a05971a..c5d68ff 100644
> --- a/block.c
> +++ b/block.c
> @@ -5497,6 +5497,26 @@ int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, int64_t sector
> }
> }
>
> +/**
> + * Chooses a default granularity based on the existing cluster size,
> + * but clamped between [4K, 64K]. Defaults to 64K in the case that there
> + * is no cluster size information available.
> + */
> +uint32_t bdrv_get_default_bitmap_granularity(BlockDriverState *bs)
> +{
> + BlockDriverInfo bdi;
> + uint32_t granularity;
> +
> + if (bdrv_get_info(bs, &bdi) >= 0 && bdi.cluster_size > 0) {
> + granularity = MAX(4096, bdi.cluster_size);
> + granularity = MIN(65536, granularity);
> + } else {
> + granularity = 65536;
> + }
> +
> + return granularity;
> +}
> +
> void bdrv_dirty_iter_init(BlockDriverState *bs,
> BdrvDirtyBitmap *bitmap, HBitmapIter *hbi)
> {
> diff --git a/block/mirror.c b/block/mirror.c
> index f8aac33..1cb700e 100644
> --- a/block/mirror.c
> +++ b/block/mirror.c
> @@ -668,15 +668,7 @@ static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target,
> MirrorBlockJob *s;
>
> if (granularity == 0) {
> - /* Choose the default granularity based on the target file's cluster
> - * size, clamped between 4k and 64k. */
> - BlockDriverInfo bdi;
> - if (bdrv_get_info(target, &bdi) >= 0 && bdi.cluster_size != 0) {
> - granularity = MAX(4096, bdi.cluster_size);
> - granularity = MIN(65536, granularity);
> - } else {
> - granularity = 65536;
> - }
> + granularity = bdrv_get_default_bitmap_granularity(target);
> }
>
> assert ((granularity & (granularity - 1)) == 0);
> diff --git a/blockdev.c b/blockdev.c
> index fbb3a79..7d71b81 100644
> --- a/blockdev.c
> +++ b/blockdev.c
> @@ -1164,6 +1164,68 @@ out_aio_context:
> return NULL;
> }
>
> +/**
> + * block_dirty_bitmap_lookup:
> + * Return a dirty bitmap (if present), after validating
> + * the node reference and bitmap names.
> + *
> + * @node: The name of the BDS node to search for bitmaps
> + * @name: The name of the bitmap to search for
> + * @pbs: Output pointer for BDS lookup, if desired. Can be NULL.
> + * @paio: Output pointer for aio_context acquisition, if desired. Can be NULL.
> + * @errp: Output pointer for error information. Can be NULL.
> + *
> + * @return: A bitmap object on success, or NULL on failure.
> + */
> +static BdrvDirtyBitmap *block_dirty_bitmap_lookup(const char *node,
> + const char *name,
> + BlockDriverState **pbs,
> + AioContext **paio,
> + Error **errp)
> +{
> + BlockDriverState *bs;
> + BdrvDirtyBitmap *bitmap;
> + AioContext *aio_context;
> +
> + if (!node) {
> + error_setg(errp, "Node cannot be NULL");
> + return NULL;
> + }
> + if (!name) {
> + error_setg(errp, "Bitmap name cannot be NULL");
> + return NULL;
> + }
> + bs = bdrv_lookup_bs(node, node, NULL);
> + if (!bs) {
> + error_setg(errp, "Node '%s' not found", node);
> + return NULL;
> + }
> +
> + aio_context = bdrv_get_aio_context(bs);
> + aio_context_acquire(aio_context);
> +
> + bitmap = bdrv_find_dirty_bitmap(bs, name);
> + if (!bitmap) {
> + error_setg(errp, "Dirty bitmap '%s' not found", name);
> + goto fail;
> + }
> +
> + if (pbs) {
> + *pbs = bs;
> + }
> + if (paio) {
> + *paio = aio_context;
> + } else {
> + aio_context_release(aio_context);
> + }
> +
> + return bitmap;
> +
> + fail:
> + aio_context_release(aio_context);
> + return NULL;
> +}
> +
> /* New and old BlockDriverState structs for atomic group operations */
>
> typedef struct BlkTransactionState BlkTransactionState;
> @@ -1953,6 +2015,61 @@ void qmp_block_set_io_throttle(const char *device, int64_t bps, int64_t bps_rd,
> aio_context_release(aio_context);
> }
>
> +void qmp_block_dirty_bitmap_add(const char *node, const char *name,
> + bool has_granularity, uint32_t granularity,
> + Error **errp)
> +{
> + AioContext *aio_context;
> + BlockDriverState *bs;
> +
> + if (!name || name[0] == '\0') {
> + error_setg(errp, "Bitmap name cannot be empty");
> + return;
> + }
> +
> + bs = bdrv_lookup_bs(node, node, errp);
> + if (!bs) {
> + return;
> + }
> +
> + aio_context = bdrv_get_aio_context(bs);
> + aio_context_acquire(aio_context);
> +
> + if (has_granularity) {
> + if (granularity < 512 || !is_power_of_2(granularity)) {
> + error_setg(errp, "Granularity must be power of 2 "
> + "and at least 512");
> + goto out;
> + }
> + } else {
> + /* Default to cluster size, if available: */
> + granularity = bdrv_get_default_bitmap_granularity(bs);
> + }
> +
> + bdrv_create_dirty_bitmap(bs, granularity, name, errp);
> +
> + out:
> + aio_context_release(aio_context);
> +}
> +
> +void qmp_block_dirty_bitmap_remove(const char *node, const char *name,
> + Error **errp)
> +{
> + AioContext *aio_context;
> + BlockDriverState *bs;
> + BdrvDirtyBitmap *bitmap;
> +
> + bitmap = block_dirty_bitmap_lookup(node, name, &bs, &aio_context, errp);
> + if (!bitmap || !bs) {
Is there actually a way for bs to be NULL if bitmap is non-NULL? In
fact, bs is never set to NULL by block_dirty_bitmap_lookup(), so it's
either uninitialized or valid. If you have to respin for some reason or
another, I think it would be nice to drop the !bs part.
Because bitmap != NULL always means bs is valid, though, this is not
wrong, and thus with or without it:
Reviewed-by: Max Reitz <mreitz@redhat.com>
> + return;
> + }
> +
> + bdrv_dirty_bitmap_make_anon(bs, bitmap);
> + bdrv_release_dirty_bitmap(bs, bitmap);
> +
> + aio_context_release(aio_context);
> +}
> +
> int hmp_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data)
> {
> const char *id = qdict_get_str(qdict, "id");
> diff --git a/include/block/block.h b/include/block/block.h
> index 5235086..0f014a3 100644
> --- a/include/block/block.h
> +++ b/include/block/block.h
> @@ -458,6 +458,7 @@ BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs,
> void bdrv_dirty_bitmap_make_anon(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
> void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
> BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs);
> +uint32_t bdrv_get_default_bitmap_granularity(BlockDriverState *bs);
> int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, int64_t sector);
> void bdrv_set_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
> int64_t cur_sector, int nr_sectors);
> diff --git a/qapi/block-core.json b/qapi/block-core.json
> index 42c9d75..faadd10 100644
> --- a/qapi/block-core.json
> +++ b/qapi/block-core.json
> @@ -960,6 +960,61 @@
> '*on-target-error': 'BlockdevOnError' } }
>
> ##
> +# @BlockDirtyBitmap
> +#
> +# @node: name of device/node which the bitmap is tracking
> +#
> +# @name: name of the dirty bitmap
> +#
> +# Since 2.4
> +##
> +{ 'type': 'BlockDirtyBitmap',
> + 'data': { 'node': 'str', 'name': 'str' } }
> +
> +##
> +# @BlockDirtyBitmapAdd
> +#
> +# @node: name of device/node which the bitmap is tracking
> +#
> +# @name: name of the dirty bitmap
> +#
> +# @granularity: #optional the bitmap granularity, default is 64k for
> +# block-dirty-bitmap-add
> +#
> +# Since 2.4
> +##
> +{ 'type': 'BlockDirtyBitmapAdd',
> + 'data': { 'node': 'str', 'name': 'str', '*granularity': 'uint32' } }
> +
> +##
> +# @block-dirty-bitmap-add
> +#
> +# Create a dirty bitmap with a name on the node
> +#
> +# Returns: nothing on success
> +# If @node is not a valid block device or node, DeviceNotFound
> +# If @name is already taken, GenericError with an explanation
> +#
> +# Since 2.4
> +##
> +{ 'command': 'block-dirty-bitmap-add',
> + 'data': 'BlockDirtyBitmapAdd' }
> +
> +##
> +# @block-dirty-bitmap-remove
> +#
> +# Remove a dirty bitmap on the node
> +#
> +# Returns: nothing on success
> +# If @node is not a valid block device or node, DeviceNotFound
> +# If @name is not found, GenericError with an explanation
> +#
> +# Since 2.4
> +##
> +{ 'command': 'block-dirty-bitmap-remove',
> + 'data': 'BlockDirtyBitmap' }
> +
> +##
> # @block_set_io_throttle:
> #
> # Change I/O throttle limits for a block drive.
> diff --git a/qmp-commands.hx b/qmp-commands.hx
> index 7f68760..e9f2eb1 100644
> --- a/qmp-commands.hx
> +++ b/qmp-commands.hx
> @@ -1270,6 +1270,62 @@ Example:
> EQMP
>
> {
> + .name = "block-dirty-bitmap-add",
> + .args_type = "node:B,name:s,granularity:i?",
> + .mhandler.cmd_new = qmp_marshal_input_block_dirty_bitmap_add,
> + },
> +
> +SQMP
> +
> +block-dirty-bitmap-add
> +----------------------
> +Since 2.4
> +
> +Create a dirty bitmap with a name on the device, and start tracking the writes.
> +
> +Arguments:
> +
> +- "node": device/node on which to create dirty bitmap (json-string)
> +- "name": name of the new dirty bitmap (json-string)
> +- "granularity": granularity to track writes with (int, optional)
> +
> +Example:
> +
> +-> { "execute": "block-dirty-bitmap-add", "arguments": { "node": "drive0",
> + "name": "bitmap0" } }
> +<- { "return": {} }
> +
> +EQMP
> +
> + {
> + .name = "block-dirty-bitmap-remove",
> + .args_type = "node:B,name:s",
> + .mhandler.cmd_new = qmp_marshal_input_block_dirty_bitmap_remove,
> + },
> +
> +SQMP
> +
> +block-dirty-bitmap-remove
> +-------------------------
> +Since 2.4
> +
> +Stop write tracking and remove the dirty bitmap that was created with
> +block-dirty-bitmap-add.
> +
> +Arguments:
> +
> +- "node": device/node on which to remove dirty bitmap (json-string)
> +- "name": name of the dirty bitmap to remove (json-string)
> +
> +Example:
> +
> +-> { "execute": "block-dirty-bitmap-remove", "arguments": { "node": "drive0",
> + "name": "bitmap0" } }
> +<- { "return": {} }
> +
> +EQMP
> +
> + {
> .name = "blockdev-snapshot-sync",
> .args_type = "device:s?,node-name:s?,snapshot-file:s,snapshot-node-name:s?,format:s?,mode:s?",
> .mhandler.cmd_new = qmp_marshal_input_blockdev_snapshot_sync,
^ permalink raw reply [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 04/20] qmp: Add block-dirty-bitmap-add and block-dirty-bitmap-remove
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 04/20] qmp: Add block-dirty-bitmap-add and block-dirty-bitmap-remove John Snow
2015-03-20 19:39 ` Max Reitz
@ 2015-04-02 9:57 ` Stefan Hajnoczi
1 sibling, 0 replies; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-02 9:57 UTC (permalink / raw)
To: John Snow
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
[-- Attachment #1: Type: text/plain, Size: 1621 bytes --]
On Fri, Mar 20, 2015 at 03:16:47PM -0400, John Snow wrote:
> The new command pair is added to manage a user created dirty bitmap. The
> dirty bitmap's name is mandatory and must be unique for the same device,
> but different devices can have bitmaps with the same names.
>
> The granularity is an optional field. If it is not specified, we will
> choose a default granularity based on the cluster size if available,
> clamped to between 4K and 64K to mirror how the 'mirror' code was
> already choosing granularity. If we do not have cluster size info
> available, we choose 64K. This code has been factored out into a helper
> shared with block/mirror.
>
> This patch also introduces the 'block_dirty_bitmap_lookup' helper,
> which takes a device name and a dirty bitmap name and validates the
> lookup, returning NULL and setting errp if there is a problem with
> either field. This helper will be re-used in future patches in this
> series.
>
> The types added to block-core.json will be re-used in future patches
> in this series, see:
> 'qapi: Add transaction support to block-dirty-bitmap-{add, enable, disable}'
>
> Signed-off-by: John Snow <jsnow@redhat.com>
> ---
> block.c | 20 +++++++++
> block/mirror.c | 10 +----
> blockdev.c | 117 ++++++++++++++++++++++++++++++++++++++++++++++++++
> include/block/block.h | 1 +
> qapi/block-core.json | 55 ++++++++++++++++++++++++
> qmp-commands.hx | 56 ++++++++++++++++++++++++
> 6 files changed, 250 insertions(+), 9 deletions(-)
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread
* [Qemu-devel] [PATCH v4 05/20] block: Introduce bdrv_dirty_bitmap_granularity()
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (3 preceding siblings ...)
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 04/20] qmp: Add block-dirty-bitmap-add and block-dirty-bitmap-remove John Snow
@ 2015-03-20 19:16 ` John Snow
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 06/20] hbitmap: cache array lengths John Snow
` (16 subsequent siblings)
21 siblings, 0 replies; 54+ messages in thread
From: John Snow @ 2015-03-20 19:16 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
This returns the granularity (in bytes) of dirty bitmap,
which matches the QMP interface and the existing query
interface.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
---
block.c | 8 ++++++--
include/block/block.h | 1 +
2 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/block.c b/block.c
index c5d68ff..2a590aa 100644
--- a/block.c
+++ b/block.c
@@ -5476,8 +5476,7 @@ BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs)
BlockDirtyInfo *info = g_new0(BlockDirtyInfo, 1);
BlockDirtyInfoList *entry = g_new0(BlockDirtyInfoList, 1);
info->count = bdrv_get_dirty_count(bs, bm);
- info->granularity =
- ((uint32_t) BDRV_SECTOR_SIZE << hbitmap_granularity(bm->bitmap));
+ info->granularity = bdrv_dirty_bitmap_granularity(bm);
info->has_name = !!bm->name;
info->name = g_strdup(bm->name);
entry->value = info;
@@ -5517,6 +5516,11 @@ uint32_t bdrv_get_default_bitmap_granularity(BlockDriverState *bs)
return granularity;
}
+uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap)
+{
+ return BDRV_SECTOR_SIZE << hbitmap_granularity(bitmap->bitmap);
+}
+
void bdrv_dirty_iter_init(BlockDriverState *bs,
BdrvDirtyBitmap *bitmap, HBitmapIter *hbi)
{
diff --git a/include/block/block.h b/include/block/block.h
index 0f014a3..493b7c5 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -459,6 +459,7 @@ void bdrv_dirty_bitmap_make_anon(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs);
uint32_t bdrv_get_default_bitmap_granularity(BlockDriverState *bs);
+uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap);
int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, int64_t sector);
void bdrv_set_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int nr_sectors);
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* [Qemu-devel] [PATCH v4 06/20] hbitmap: cache array lengths
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (4 preceding siblings ...)
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 05/20] block: Introduce bdrv_dirty_bitmap_granularity() John Snow
@ 2015-03-20 19:16 ` John Snow
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 07/20] hbitmap: add hbitmap_merge John Snow
` (15 subsequent siblings)
21 siblings, 0 replies; 54+ messages in thread
From: John Snow @ 2015-03-20 19:16 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
As a convenience: between incremental backups, bitmap migrations
and bitmap persistence we seem to need to recalculate these a lot.
Because the lengths are a little bit-twiddly, let's just solidly
cache them and be done with it.
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
---
util/hbitmap.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/util/hbitmap.c b/util/hbitmap.c
index ab13971..5b78613 100644
--- a/util/hbitmap.c
+++ b/util/hbitmap.c
@@ -90,6 +90,9 @@ struct HBitmap {
* bitmap will still allocate HBITMAP_LEVELS arrays.
*/
unsigned long *levels[HBITMAP_LEVELS];
+
+ /* The length of each levels[] array. */
+ uint64_t sizes[HBITMAP_LEVELS];
};
/* Advance hbi to the next nonzero word and return it. hbi->pos
@@ -384,6 +387,7 @@ HBitmap *hbitmap_alloc(uint64_t size, int granularity)
hb->granularity = granularity;
for (i = HBITMAP_LEVELS; i-- > 0; ) {
size = MAX((size + BITS_PER_LONG - 1) >> BITS_PER_LEVEL, 1);
+ hb->sizes[i] = size;
hb->levels[i] = g_new0(unsigned long, size);
}
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* [Qemu-devel] [PATCH v4 07/20] hbitmap: add hbitmap_merge
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (5 preceding siblings ...)
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 06/20] hbitmap: cache array lengths John Snow
@ 2015-03-20 19:16 ` John Snow
2015-04-02 12:19 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 08/20] block: Add bitmap disabled status John Snow
` (14 subsequent siblings)
21 siblings, 1 reply; 54+ messages in thread
From: John Snow @ 2015-03-20 19:16 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
We add a bitmap merge operation to assist in error cases
where we wish to combine two bitmaps together.
This is algorithmically O(bits) provided HBITMAP_LEVELS remains
constant. For a full bitmap on a 64bit machine:
sum(bits/64^k, k, 0, HBITMAP_LEVELS) ~= 1.01587 * bits
We may be able to improve running speed for particularly sparse
bitmaps by using iterators, but the running time for dense maps
will be worse.
We present the simpler solution first, and we can refine it later
if needed.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
include/qemu/hbitmap.h | 11 +++++++++++
util/hbitmap.c | 29 +++++++++++++++++++++++++++++
2 files changed, 40 insertions(+)
diff --git a/include/qemu/hbitmap.h b/include/qemu/hbitmap.h
index 550d7ce..c19c1cb 100644
--- a/include/qemu/hbitmap.h
+++ b/include/qemu/hbitmap.h
@@ -65,6 +65,17 @@ struct HBitmapIter {
HBitmap *hbitmap_alloc(uint64_t size, int granularity);
/**
+ * hbitmap_merge:
+ * @a: The bitmap to store the result in.
+ * @b: The bitmap to merge into @a.
+ *
+ * Merge two bitmaps together.
+ * A := A (BITOR) B.
+ * B is left unmodified.
+ */
+bool hbitmap_merge(HBitmap *a, const HBitmap *b);
+
+/**
* hbitmap_empty:
* @hb: HBitmap to operate on.
*
diff --git a/util/hbitmap.c b/util/hbitmap.c
index 5b78613..ba11fd3 100644
--- a/util/hbitmap.c
+++ b/util/hbitmap.c
@@ -399,3 +399,32 @@ HBitmap *hbitmap_alloc(uint64_t size, int granularity)
hb->levels[0][0] |= 1UL << (BITS_PER_LONG - 1);
return hb;
}
+
+/**
+ * Given HBitmaps A and B, let A := A (BITOR) B.
+ * Bitmap B will not be modified.
+ */
+bool hbitmap_merge(HBitmap *a, const HBitmap *b)
+{
+ int i, j;
+
+ if ((a->size != b->size) || (a->granularity != b->granularity)) {
+ return false;
+ }
+
+ if (hbitmap_count(b) == 0) {
+ return true;
+ }
+
+ /* This merge is O(size), as BITS_PER_LONG and HBITMAP_LEVELS are constant.
+ * It may be possible to improve running times for sparsely populated maps
+ * by using hbitmap_iter_next, but this is suboptimal for dense maps.
+ */
+ for (i = HBITMAP_LEVELS - 1; i >= 0; i--) {
+ for (j = 0; j < a->sizes[i]; j++) {
+ a->levels[i][j] |= b->levels[i][j];
+ }
+ }
+
+ return true;
+}
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 07/20] hbitmap: add hbitmap_merge
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 07/20] hbitmap: add hbitmap_merge John Snow
@ 2015-04-02 12:19 ` Stefan Hajnoczi
0 siblings, 0 replies; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-02 12:19 UTC (permalink / raw)
To: John Snow
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
[-- Attachment #1: Type: text/plain, Size: 895 bytes --]
On Fri, Mar 20, 2015 at 03:16:50PM -0400, John Snow wrote:
> We add a bitmap merge operation to assist in error cases
> where we wish to combine two bitmaps together.
>
> This is algorithmically O(bits) provided HBITMAP_LEVELS remains
> constant. For a full bitmap on a 64bit machine:
> sum(bits/64^k, k, 0, HBITMAP_LEVELS) ~= 1.01587 * bits
>
> We may be able to improve running speed for particularly sparse
> bitmaps by using iterators, but the running time for dense maps
> will be worse.
>
> We present the simpler solution first, and we can refine it later
> if needed.
>
> Signed-off-by: John Snow <jsnow@redhat.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
> ---
> include/qemu/hbitmap.h | 11 +++++++++++
> util/hbitmap.c | 29 +++++++++++++++++++++++++++++
> 2 files changed, 40 insertions(+)
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread
* [Qemu-devel] [PATCH v4 08/20] block: Add bitmap disabled status
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (6 preceding siblings ...)
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 07/20] hbitmap: add hbitmap_merge John Snow
@ 2015-03-20 19:16 ` John Snow
2015-04-02 12:21 ` Stefan Hajnoczi
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 09/20] block: Add bitmap successors John Snow
` (13 subsequent siblings)
21 siblings, 1 reply; 54+ messages in thread
From: John Snow @ 2015-03-20 19:16 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
Add a status indicating the enabled/disabled state of the bitmap.
A bitmap is by default enabled, but you can lock the bitmap into
a read-only state by setting disabled = true.
A previous version of this patch added a QMP interface for changing
the state of the bitmap, but it has since been removed for now until
a use case emerges where this state must be revealed to the user.
The disabled state WILL be used internally for bitmap migration and
bitmap persistence.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
block.c | 25 +++++++++++++++++++++++++
include/block/block.h | 3 +++
2 files changed, 28 insertions(+)
diff --git a/block.c b/block.c
index 2a590aa..0bf5565 100644
--- a/block.c
+++ b/block.c
@@ -54,6 +54,7 @@
struct BdrvDirtyBitmap {
HBitmap *bitmap;
char *name;
+ bool disabled;
QLIST_ENTRY(BdrvDirtyBitmap) list;
};
@@ -5448,10 +5449,16 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
bitmap = g_new0(BdrvDirtyBitmap, 1);
bitmap->bitmap = hbitmap_alloc(bitmap_size, ffs(sector_granularity) - 1);
bitmap->name = g_strdup(name);
+ bitmap->disabled = false;
QLIST_INSERT_HEAD(&bs->dirty_bitmaps, bitmap, list);
return bitmap;
}
+bool bdrv_dirty_bitmap_enabled(BdrvDirtyBitmap *bitmap)
+{
+ return !bitmap->disabled;
+}
+
void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
{
BdrvDirtyBitmap *bm, *next;
@@ -5466,6 +5473,16 @@ void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
}
}
+void bdrv_disable_dirty_bitmap(BdrvDirtyBitmap *bitmap)
+{
+ bitmap->disabled = true;
+}
+
+void bdrv_enable_dirty_bitmap(BdrvDirtyBitmap *bitmap)
+{
+ bitmap->disabled = false;
+}
+
BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs)
{
BdrvDirtyBitmap *bm;
@@ -5530,12 +5547,14 @@ void bdrv_dirty_iter_init(BlockDriverState *bs,
void bdrv_set_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int nr_sectors)
{
+ assert(bdrv_dirty_bitmap_enabled(bitmap));
hbitmap_set(bitmap->bitmap, cur_sector, nr_sectors);
}
void bdrv_reset_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int nr_sectors)
{
+ assert(bdrv_dirty_bitmap_enabled(bitmap));
hbitmap_reset(bitmap->bitmap, cur_sector, nr_sectors);
}
@@ -5544,6 +5563,9 @@ static void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector,
{
BdrvDirtyBitmap *bitmap;
QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
+ if (!bdrv_dirty_bitmap_enabled(bitmap)) {
+ continue;
+ }
hbitmap_set(bitmap->bitmap, cur_sector, nr_sectors);
}
}
@@ -5553,6 +5575,9 @@ static void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector,
{
BdrvDirtyBitmap *bitmap;
QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
+ if (!bdrv_dirty_bitmap_enabled(bitmap)) {
+ continue;
+ }
hbitmap_reset(bitmap->bitmap, cur_sector, nr_sectors);
}
}
diff --git a/include/block/block.h b/include/block/block.h
index 493b7c5..029a8a7 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -457,9 +457,12 @@ BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs,
const char *name);
void bdrv_dirty_bitmap_make_anon(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
+void bdrv_disable_dirty_bitmap(BdrvDirtyBitmap *bitmap);
+void bdrv_enable_dirty_bitmap(BdrvDirtyBitmap *bitmap);
BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs);
uint32_t bdrv_get_default_bitmap_granularity(BlockDriverState *bs);
uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap);
+bool bdrv_dirty_bitmap_enabled(BdrvDirtyBitmap *bitmap);
int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, int64_t sector);
void bdrv_set_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int nr_sectors);
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [PATCH v4 08/20] block: Add bitmap disabled status
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 08/20] block: Add bitmap disabled status John Snow
@ 2015-04-02 12:21 ` Stefan Hajnoczi
0 siblings, 0 replies; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-02 12:21 UTC (permalink / raw)
To: John Snow
Cc: kwolf, famz, qemu-block, qemu-devel, armbru, vsementsov,
stefanha, mreitz
[-- Attachment #1: Type: text/plain, Size: 894 bytes --]
On Fri, Mar 20, 2015 at 03:16:51PM -0400, John Snow wrote:
> Add a status indicating the enabled/disabled state of the bitmap.
> A bitmap is by default enabled, but you can lock the bitmap into
> a read-only state by setting disabled = true.
>
> A previous version of this patch added a QMP interface for changing
> the state of the bitmap, but it has since been removed for now until
> a use case emerges where this state must be revealed to the user.
>
> The disabled state WILL be used internally for bitmap migration and
> bitmap persistence.
>
> Signed-off-by: Fam Zheng <famz@redhat.com>
> Signed-off-by: John Snow <jsnow@redhat.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
> ---
> block.c | 25 +++++++++++++++++++++++++
> include/block/block.h | 3 +++
> 2 files changed, 28 insertions(+)
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread
* [Qemu-devel] [PATCH v4 09/20] block: Add bitmap successors
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (7 preceding siblings ...)
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 08/20] block: Add bitmap disabled status John Snow
@ 2015-03-20 19:16 ` John Snow
2015-04-02 12:23 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 10/20] qmp: Add support of "dirty-bitmap" sync mode for drive-backup John Snow
` (12 subsequent siblings)
21 siblings, 1 reply; 54+ messages in thread
From: John Snow @ 2015-03-20 19:16 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
A bitmap successor is an anonymous BdrvDirtyBitmap that is intended to
be created just prior to a sensitive operation (e.g. Incremental Backup)
that can either succeed or fail, but during the course of which we still
want a bitmap tracking writes.
On creating a successor, we "freeze" the parent bitmap which prevents
its deletion, enabling, anonymization, or creating a bitmap with the
same name.
On success, the parent bitmap can "abdicate" responsibility to the
successor, which will inherit its name. The successor will have been
tracking writes during the course of the backup operation. The parent
will be safely deleted.
On failure, we can "reclaim" the successor from the parent, unifying
them such that the resulting bitmap describes all writes occurring since
the last successful backup, for instance. Reclamation will thaw the
parent, but not explicitly re-enable it.
BdrvDirtyBitmap operations that target a single bitmap are protected
by assertions that the bitmap is not frozen and/or disabled.
BdrvDirtyBitmap operations that target a group of bitmaps, such as
bdrv_{set,reset}_dirty will ignore frozen/disabled drives with a
conditional instead.
QMP transactions that enable/disable bitmaps have extra error checking
surrounding them that prevent modifying bitmaps that are frozen.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
block.c | 104 +++++++++++++++++++++++++++++++++++++++++++++++++-
blockdev.c | 7 ++++
include/block/block.h | 10 +++++
qapi/block-core.json | 1 +
4 files changed, 121 insertions(+), 1 deletion(-)
diff --git a/block.c b/block.c
index 0bf5565..2fff00b 100644
--- a/block.c
+++ b/block.c
@@ -51,8 +51,17 @@
#include <windows.h>
#endif
+/**
+ * A BdrvDirtyBitmap can be in three possible states:
+ * (1) successor is false and disabled is false: full r/w mode
+ * (2) successor is false and disabled is true: read only mode ("disabled")
+ * (3) successor is set: frozen mode.
+ * A frozen bitmap cannot be renamed, deleted, anonymized, cleared, set,
+ * or enabled. A frozen bitmap can only abdicate() or reclaim().
+ */
struct BdrvDirtyBitmap {
HBitmap *bitmap;
+ BdrvDirtyBitmap *successor;
char *name;
bool disabled;
QLIST_ENTRY(BdrvDirtyBitmap) list;
@@ -5419,6 +5428,7 @@ BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs, const char *name)
void bdrv_dirty_bitmap_make_anon(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
{
+ assert(!bdrv_dirty_bitmap_frozen(bitmap));
g_free(bitmap->name);
bitmap->name = NULL;
}
@@ -5454,9 +5464,98 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
return bitmap;
}
+bool bdrv_dirty_bitmap_frozen(BdrvDirtyBitmap *bitmap)
+{
+ return bitmap->successor;
+}
+
bool bdrv_dirty_bitmap_enabled(BdrvDirtyBitmap *bitmap)
{
- return !bitmap->disabled;
+ return !(bitmap->disabled || bitmap->successor);
+}
+
+/**
+ * Create a successor bitmap destined to replace this bitmap after an operation.
+ * Requires that the bitmap is not frozen and has no successor.
+ */
+int bdrv_dirty_bitmap_create_successor(BlockDriverState *bs,
+ BdrvDirtyBitmap *bitmap, Error **errp)
+{
+ uint64_t granularity;
+ BdrvDirtyBitmap *child;
+
+ if (bdrv_dirty_bitmap_frozen(bitmap)) {
+ error_setg(errp, "Cannot create a successor for a bitmap that is "
+ "currently frozen");
+ return -1;
+ }
+ assert(!bitmap->successor);
+
+ /* Create an anonymous successor */
+ granularity = bdrv_dirty_bitmap_granularity(bitmap);
+ child = bdrv_create_dirty_bitmap(bs, granularity, NULL, errp);
+ if (!child) {
+ return -1;
+ }
+
+ /* Successor will be on or off based on our current state. */
+ child->disabled = bitmap->disabled;
+
+ /* Install the successor and freeze the parent */
+ bitmap->successor = child;
+ return 0;
+}
+
+/**
+ * For a bitmap with a successor, yield our name to the successor,
+ * Delete the old bitmap, and return a handle to the new bitmap.
+ */
+BdrvDirtyBitmap *bdrv_dirty_bitmap_abdicate(BlockDriverState *bs,
+ BdrvDirtyBitmap *bitmap,
+ Error **errp)
+{
+ char *name;
+ BdrvDirtyBitmap *successor = bitmap->successor;
+
+ if (successor == NULL) {
+ error_setg(errp, "Cannot relinquish control if "
+ "there's no successor present");
+ return NULL;
+ }
+
+ name = bitmap->name;
+ bitmap->name = NULL;
+ successor->name = name;
+ bitmap->successor = NULL;
+ bdrv_release_dirty_bitmap(bs, bitmap);
+
+ return successor;
+}
+
+/**
+ * In cases of failure where we can no longer safely delete the parent,
+ * We may wish to re-join the parent and child/successor.
+ * The merged parent will be un-frozen, but not explicitly re-enabled.
+ */
+BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs,
+ BdrvDirtyBitmap *parent,
+ Error **errp)
+{
+ BdrvDirtyBitmap *successor = parent->successor;
+
+ if (!successor) {
+ error_setg(errp, "Cannot reclaim a successor when none is present");
+ return NULL;
+ }
+
+ if (!hbitmap_merge(parent->bitmap, successor->bitmap)) {
+ error_setg(errp, "Merging of parent and successor bitmap failed");
+ return NULL;
+ }
+ bdrv_release_dirty_bitmap(bs, successor);
+ parent->successor = NULL;
+
+ return parent;
}
void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
@@ -5464,6 +5563,7 @@ void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
BdrvDirtyBitmap *bm, *next;
QLIST_FOREACH_SAFE(bm, &bs->dirty_bitmaps, list, next) {
if (bm == bitmap) {
+ assert(!bdrv_dirty_bitmap_frozen(bm));
QLIST_REMOVE(bitmap, list);
hbitmap_free(bitmap->bitmap);
g_free(bitmap->name);
@@ -5475,11 +5575,13 @@ void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
void bdrv_disable_dirty_bitmap(BdrvDirtyBitmap *bitmap)
{
+ assert(!bdrv_dirty_bitmap_frozen(bitmap));
bitmap->disabled = true;
}
void bdrv_enable_dirty_bitmap(BdrvDirtyBitmap *bitmap)
{
+ assert(!bdrv_dirty_bitmap_frozen(bitmap));
bitmap->disabled = false;
}
diff --git a/blockdev.c b/blockdev.c
index 7d71b81..373d19a 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -2064,9 +2064,16 @@ void qmp_block_dirty_bitmap_remove(const char *node, const char *name,
return;
}
+ if (bdrv_dirty_bitmap_frozen(bitmap)) {
+ error_setg(errp,
+ "Bitmap '%s' is currently frozen and cannot be removed",
+ name);
+ goto out;
+ }
bdrv_dirty_bitmap_make_anon(bs, bitmap);
bdrv_release_dirty_bitmap(bs, bitmap);
+ out:
aio_context_release(aio_context);
}
diff --git a/include/block/block.h b/include/block/block.h
index 029a8a7..b02c670 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -453,6 +453,15 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
uint32_t granularity,
const char *name,
Error **errp);
+int bdrv_dirty_bitmap_create_successor(BlockDriverState *bs,
+ BdrvDirtyBitmap *bitmap,
+ Error **errp);
+BdrvDirtyBitmap *bdrv_dirty_bitmap_abdicate(BlockDriverState *bs,
+ BdrvDirtyBitmap *bitmap,
+ Error **errp);
+BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs,
+ BdrvDirtyBitmap *bitmap,
+ Error **errp);
BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs,
const char *name);
void bdrv_dirty_bitmap_make_anon(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
@@ -463,6 +472,7 @@ BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs);
uint32_t bdrv_get_default_bitmap_granularity(BlockDriverState *bs);
uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap);
bool bdrv_dirty_bitmap_enabled(BdrvDirtyBitmap *bitmap);
+bool bdrv_dirty_bitmap_frozen(BdrvDirtyBitmap *bitmap);
int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, int64_t sector);
void bdrv_set_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int nr_sectors);
diff --git a/qapi/block-core.json b/qapi/block-core.json
index faadd10..725a2a3 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -1008,6 +1008,7 @@
# Returns: nothing on success
# If @node is not a valid block device or node, DeviceNotFound
# If @name is not found, GenericError with an explanation
+# if @name is frozen by an operation, GenericError
#
# Since 2.4
##
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 09/20] block: Add bitmap successors
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 09/20] block: Add bitmap successors John Snow
@ 2015-04-02 12:23 ` Stefan Hajnoczi
0 siblings, 0 replies; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-02 12:23 UTC (permalink / raw)
To: John Snow
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
[-- Attachment #1: Type: text/plain, Size: 1852 bytes --]
On Fri, Mar 20, 2015 at 03:16:52PM -0400, John Snow wrote:
> A bitmap successor is an anonymous BdrvDirtyBitmap that is intended to
> be created just prior to a sensitive operation (e.g. Incremental Backup)
> that can either succeed or fail, but during the course of which we still
> want a bitmap tracking writes.
>
> On creating a successor, we "freeze" the parent bitmap which prevents
> its deletion, enabling, anonymization, or creating a bitmap with the
> same name.
>
> On success, the parent bitmap can "abdicate" responsibility to the
> successor, which will inherit its name. The successor will have been
> tracking writes during the course of the backup operation. The parent
> will be safely deleted.
>
> On failure, we can "reclaim" the successor from the parent, unifying
> them such that the resulting bitmap describes all writes occurring since
> the last successful backup, for instance. Reclamation will thaw the
> parent, but not explicitly re-enable it.
>
> BdrvDirtyBitmap operations that target a single bitmap are protected
> by assertions that the bitmap is not frozen and/or disabled.
>
> BdrvDirtyBitmap operations that target a group of bitmaps, such as
> bdrv_{set,reset}_dirty will ignore frozen/disabled drives with a
> conditional instead.
>
> QMP transactions that enable/disable bitmaps have extra error checking
> surrounding them that prevent modifying bitmaps that are frozen.
>
> Signed-off-by: John Snow <jsnow@redhat.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
> ---
> block.c | 104 +++++++++++++++++++++++++++++++++++++++++++++++++-
> blockdev.c | 7 ++++
> include/block/block.h | 10 +++++
> qapi/block-core.json | 1 +
> 4 files changed, 121 insertions(+), 1 deletion(-)
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread
* [Qemu-devel] [PATCH v4 10/20] qmp: Add support of "dirty-bitmap" sync mode for drive-backup
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (8 preceding siblings ...)
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 09/20] block: Add bitmap successors John Snow
@ 2015-03-20 19:16 ` John Snow
2015-04-02 12:44 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 11/20] qmp: add block-dirty-bitmap-clear John Snow
` (11 subsequent siblings)
21 siblings, 1 reply; 54+ messages in thread
From: John Snow @ 2015-03-20 19:16 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
For "dirty-bitmap" sync mode, the block job will iterate through the
given dirty bitmap to decide if a sector needs backup (backup all the
dirty clusters and skip clean ones), just as allocation conditions of
"top" sync mode.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
block.c | 9 +++
block/backup.c | 148 +++++++++++++++++++++++++++++++++++++++-------
block/mirror.c | 4 ++
blockdev.c | 18 +++++-
hmp.c | 3 +-
include/block/block.h | 1 +
include/block/block_int.h | 2 +
qapi/block-core.json | 13 ++--
qmp-commands.hx | 7 ++-
9 files changed, 171 insertions(+), 34 deletions(-)
diff --git a/block.c b/block.c
index 2fff00b..63cdedf 100644
--- a/block.c
+++ b/block.c
@@ -5684,6 +5684,15 @@ static void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector,
}
}
+/**
+ * Advance an HBitmapIter to an arbitrary offset.
+ */
+void bdrv_set_dirty_iter(HBitmapIter *hbi, int64_t offset)
+{
+ assert(hbi->hb);
+ hbitmap_iter_init(hbi, hbi->hb, offset);
+}
+
int64_t bdrv_get_dirty_count(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
{
return hbitmap_count(bitmap->bitmap);
diff --git a/block/backup.c b/block/backup.c
index 1c535b1..2639ba8 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -37,6 +37,8 @@ typedef struct CowRequest {
typedef struct BackupBlockJob {
BlockJob common;
BlockDriverState *target;
+ /* bitmap for sync=dirty-bitmap */
+ BdrvDirtyBitmap *sync_bitmap;
MirrorSyncMode sync_mode;
RateLimit limit;
BlockdevOnError on_source_error;
@@ -242,6 +244,31 @@ static void backup_complete(BlockJob *job, void *opaque)
g_free(data);
}
+static bool coroutine_fn yield_and_check(BackupBlockJob *job)
+{
+ if (block_job_is_cancelled(&job->common)) {
+ return true;
+ }
+
+ /* we need to yield so that qemu_aio_flush() returns.
+ * (without, VM does not reboot)
+ */
+ if (job->common.speed) {
+ uint64_t delay_ns = ratelimit_calculate_delay(&job->limit,
+ job->sectors_read);
+ job->sectors_read = 0;
+ block_job_sleep_ns(&job->common, QEMU_CLOCK_REALTIME, delay_ns);
+ } else {
+ block_job_sleep_ns(&job->common, QEMU_CLOCK_REALTIME, 0);
+ }
+
+ if (block_job_is_cancelled(&job->common)) {
+ return true;
+ }
+
+ return false;
+}
+
static void coroutine_fn backup_run(void *opaque)
{
BackupBlockJob *job = opaque;
@@ -254,13 +281,13 @@ static void coroutine_fn backup_run(void *opaque)
};
int64_t start, end;
int ret = 0;
+ bool error_is_read;
QLIST_INIT(&job->inflight_reqs);
qemu_co_rwlock_init(&job->flush_rwlock);
start = 0;
- end = DIV_ROUND_UP(job->common.len / BDRV_SECTOR_SIZE,
- BACKUP_SECTORS_PER_CLUSTER);
+ end = DIV_ROUND_UP(job->common.len, BACKUP_CLUSTER_SIZE);
job->bitmap = hbitmap_alloc(end, 0);
@@ -278,28 +305,62 @@ static void coroutine_fn backup_run(void *opaque)
qemu_coroutine_yield();
job->common.busy = true;
}
+ } else if (job->sync_mode == MIRROR_SYNC_MODE_DIRTY_BITMAP) {
+ /* Dirty Bitmap sync has a slightly different iteration method */
+ HBitmapIter hbi;
+ int64_t sector;
+ int64_t cluster;
+ int64_t last_cluster = -1;
+ bool polyrhythmic;
+
+ bdrv_dirty_iter_init(bs, job->sync_bitmap, &hbi);
+ /* Does the granularity happen to match our backup cluster size? */
+ polyrhythmic = (bdrv_dirty_bitmap_granularity(job->sync_bitmap) !=
+ BACKUP_CLUSTER_SIZE);
+
+ /* Find the next dirty /sector/ and copy that /cluster/ */
+ while ((sector = hbitmap_iter_next(&hbi)) != -1) {
+ cluster = sector / BACKUP_SECTORS_PER_CLUSTER;
+
+ /* Fake progress updates for any clusters we skipped,
+ * excluding this current cluster. */
+ if (cluster != last_cluster + 1) {
+ job->common.offset += ((cluster - last_cluster - 1) *
+ BACKUP_CLUSTER_SIZE);
+ }
+
+ if (yield_and_check(job)) {
+ goto leave;
+ }
+
+ do {
+ ret = backup_do_cow(bs, cluster * BACKUP_SECTORS_PER_CLUSTER,
+ BACKUP_SECTORS_PER_CLUSTER, &error_is_read);
+ if ((ret < 0) &&
+ backup_error_action(job, error_is_read, -ret) ==
+ BLOCK_ERROR_ACTION_REPORT) {
+ goto leave;
+ }
+ } while (ret < 0);
+
+ /* Advance (or rewind) our iterator if we need to. */
+ if (polyrhythmic) {
+ bdrv_set_dirty_iter(&hbi,
+ (cluster + 1) * BACKUP_SECTORS_PER_CLUSTER);
+ }
+
+ last_cluster = cluster;
+ }
+
+ /* Play some final catchup with the progress meter */
+ if (last_cluster + 1 < end) {
+ job->common.offset += ((end - last_cluster - 1) *
+ BACKUP_CLUSTER_SIZE);
+ }
} else {
/* Both FULL and TOP SYNC_MODE's require copying.. */
for (; start < end; start++) {
- bool error_is_read;
-
- if (block_job_is_cancelled(&job->common)) {
- break;
- }
-
- /* we need to yield so that qemu_aio_flush() returns.
- * (without, VM does not reboot)
- */
- if (job->common.speed) {
- uint64_t delay_ns = ratelimit_calculate_delay(
- &job->limit, job->sectors_read);
- job->sectors_read = 0;
- block_job_sleep_ns(&job->common, QEMU_CLOCK_REALTIME, delay_ns);
- } else {
- block_job_sleep_ns(&job->common, QEMU_CLOCK_REALTIME, 0);
- }
-
- if (block_job_is_cancelled(&job->common)) {
+ if (yield_and_check(job)) {
break;
}
@@ -351,12 +412,25 @@ static void coroutine_fn backup_run(void *opaque)
}
}
+leave:
notifier_with_return_remove(&before_write);
/* wait until pending backup_do_cow() calls have completed */
qemu_co_rwlock_wrlock(&job->flush_rwlock);
qemu_co_rwlock_unlock(&job->flush_rwlock);
+ if (job->sync_bitmap) {
+ BdrvDirtyBitmap *bm;
+ if (ret < 0) {
+ /* Merge the successor back into the parent, delete nothing. */
+ bm = bdrv_reclaim_dirty_bitmap(bs, job->sync_bitmap, NULL);
+ assert(bm);
+ } else {
+ /* Everything is fine, delete this bitmap and install the backup. */
+ bm = bdrv_dirty_bitmap_abdicate(bs, job->sync_bitmap, NULL);
+ assert(bm);
+ }
+ }
hbitmap_free(job->bitmap);
bdrv_iostatus_disable(target);
@@ -369,6 +443,7 @@ static void coroutine_fn backup_run(void *opaque)
void backup_start(BlockDriverState *bs, BlockDriverState *target,
int64_t speed, MirrorSyncMode sync_mode,
+ BdrvDirtyBitmap *sync_bitmap,
BlockdevOnError on_source_error,
BlockdevOnError on_target_error,
BlockCompletionFunc *cb, void *opaque,
@@ -412,17 +487,36 @@ void backup_start(BlockDriverState *bs, BlockDriverState *target,
return;
}
+ if (sync_mode == MIRROR_SYNC_MODE_DIRTY_BITMAP) {
+ if (!sync_bitmap) {
+ error_setg(errp, "must provide a valid bitmap name for "
+ "\"dirty-bitmap\" sync mode");
+ return;
+ }
+
+ /* Create a new bitmap, and freeze/disable this one. */
+ if (bdrv_dirty_bitmap_create_successor(bs, sync_bitmap, errp) < 0) {
+ return;
+ }
+ } else if (sync_bitmap) {
+ error_setg(errp,
+ "a sync_bitmap was provided to backup_run, "
+ "but received an incompatible sync_mode (%s)",
+ MirrorSyncMode_lookup[sync_mode]);
+ return;
+ }
+
len = bdrv_getlength(bs);
if (len < 0) {
error_setg_errno(errp, -len, "unable to get length for '%s'",
bdrv_get_device_name(bs));
- return;
+ goto error;
}
BackupBlockJob *job = block_job_create(&backup_job_driver, bs, speed,
cb, opaque, errp);
if (!job) {
- return;
+ goto error;
}
bdrv_op_block_all(target, job->common.blocker);
@@ -431,7 +525,15 @@ void backup_start(BlockDriverState *bs, BlockDriverState *target,
job->on_target_error = on_target_error;
job->target = target;
job->sync_mode = sync_mode;
+ job->sync_bitmap = sync_mode == MIRROR_SYNC_MODE_DIRTY_BITMAP ?
+ sync_bitmap : NULL;
job->common.len = len;
job->common.co = qemu_coroutine_create(backup_run);
qemu_coroutine_enter(job->common.co, job);
+ return;
+
+ error:
+ if (sync_bitmap) {
+ bdrv_reclaim_dirty_bitmap(bs, sync_bitmap, NULL);
+ }
}
diff --git a/block/mirror.c b/block/mirror.c
index 1cb700e..f89eccf 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -718,6 +718,10 @@ void mirror_start(BlockDriverState *bs, BlockDriverState *target,
bool is_none_mode;
BlockDriverState *base;
+ if (mode == MIRROR_SYNC_MODE_DIRTY_BITMAP) {
+ error_setg(errp, "Sync mode 'dirty-bitmap' not supported");
+ return;
+ }
is_none_mode = mode == MIRROR_SYNC_MODE_NONE;
base = mode == MIRROR_SYNC_MODE_TOP ? bs->backing_hd : NULL;
mirror_start_job(bs, target, replaces,
diff --git a/blockdev.c b/blockdev.c
index 373d19a..90ba5b6 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1584,6 +1584,7 @@ static void drive_backup_prepare(BlkTransactionState *common, Error **errp)
backup->sync,
backup->has_mode, backup->mode,
backup->has_speed, backup->speed,
+ backup->has_bitmap, backup->bitmap,
backup->has_on_source_error, backup->on_source_error,
backup->has_on_target_error, backup->on_target_error,
&local_err);
@@ -2394,6 +2395,7 @@ void qmp_drive_backup(const char *device, const char *target,
enum MirrorSyncMode sync,
bool has_mode, enum NewImageMode mode,
bool has_speed, int64_t speed,
+ bool has_bitmap, const char *bitmap,
bool has_on_source_error, BlockdevOnError on_source_error,
bool has_on_target_error, BlockdevOnError on_target_error,
Error **errp)
@@ -2402,6 +2404,7 @@ void qmp_drive_backup(const char *device, const char *target,
BlockDriverState *bs;
BlockDriverState *target_bs;
BlockDriverState *source = NULL;
+ BdrvDirtyBitmap *bmap = NULL;
AioContext *aio_context;
BlockDriver *drv = NULL;
Error *local_err = NULL;
@@ -2501,7 +2504,16 @@ void qmp_drive_backup(const char *device, const char *target,
bdrv_set_aio_context(target_bs, aio_context);
- backup_start(bs, target_bs, speed, sync, on_source_error, on_target_error,
+ if (has_bitmap) {
+ bmap = bdrv_find_dirty_bitmap(bs, bitmap);
+ if (!bmap) {
+ error_setg(errp, "Bitmap '%s' could not be found", bitmap);
+ goto out;
+ }
+ }
+
+ backup_start(bs, target_bs, speed, sync, bmap,
+ on_source_error, on_target_error,
block_job_cb, bs, &local_err);
if (local_err != NULL) {
bdrv_unref(target_bs);
@@ -2562,8 +2574,8 @@ void qmp_blockdev_backup(const char *device, const char *target,
bdrv_ref(target_bs);
bdrv_set_aio_context(target_bs, aio_context);
- backup_start(bs, target_bs, speed, sync, on_source_error, on_target_error,
- block_job_cb, bs, &local_err);
+ backup_start(bs, target_bs, speed, sync, NULL, 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);
diff --git a/hmp.c b/hmp.c
index f31ae27..d85d913 100644
--- a/hmp.c
+++ b/hmp.c
@@ -1061,7 +1061,8 @@ void hmp_drive_backup(Monitor *mon, const QDict *qdict)
qmp_drive_backup(device, filename, !!format, format,
full ? MIRROR_SYNC_MODE_FULL : MIRROR_SYNC_MODE_TOP,
- true, mode, false, 0, false, 0, false, 0, &err);
+ true, mode, false, 0, false, NULL,
+ false, 0, false, 0, &err);
hmp_handle_error(mon, &err);
}
diff --git a/include/block/block.h b/include/block/block.h
index b02c670..80ac2cc 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -480,6 +480,7 @@ void bdrv_reset_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int nr_sectors);
void bdrv_dirty_iter_init(BlockDriverState *bs,
BdrvDirtyBitmap *bitmap, struct HBitmapIter *hbi);
+void bdrv_set_dirty_iter(struct HBitmapIter *hbi, int64_t offset);
int64_t bdrv_get_dirty_count(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
void bdrv_enable_copy_on_read(BlockDriverState *bs);
diff --git a/include/block/block_int.h b/include/block/block_int.h
index fb9e100..e0d5561 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -602,6 +602,7 @@ void mirror_start(BlockDriverState *bs, BlockDriverState *target,
* @target: Block device to write to.
* @speed: The maximum speed, in bytes per second, or 0 for unlimited.
* @sync_mode: What parts of the disk image should be copied to the destination.
+ * @sync_bitmap: The dirty bitmap if sync_mode is MIRROR_SYNC_MODE_DIRTY_BITMAP.
* @on_source_error: The action to take upon error reading from the source.
* @on_target_error: The action to take upon error writing to the target.
* @cb: Completion function for the job.
@@ -612,6 +613,7 @@ void mirror_start(BlockDriverState *bs, BlockDriverState *target,
*/
void backup_start(BlockDriverState *bs, BlockDriverState *target,
int64_t speed, MirrorSyncMode sync_mode,
+ BdrvDirtyBitmap *sync_bitmap,
BlockdevOnError on_source_error,
BlockdevOnError on_target_error,
BlockCompletionFunc *cb, void *opaque,
diff --git a/qapi/block-core.json b/qapi/block-core.json
index 725a2a3..c17a7e9 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -512,10 +512,12 @@
#
# @none: only copy data written from now on
#
+# @dirty-bitmap: only copy data described by the dirty bitmap. Since: 2.4
+#
# Since: 1.3
##
{ 'enum': 'MirrorSyncMode',
- 'data': ['top', 'full', 'none'] }
+ 'data': ['top', 'full', 'none', 'dirty-bitmap'] }
##
# @BlockJobType:
@@ -690,14 +692,17 @@
# probe if @mode is 'existing', else the format of the source
#
# @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).
+# (all the disk, only the sectors allocated in the topmost image, from a
+# dirty bitmap, or only new I/O).
#
# @mode: #optional whether and how QEMU should create a new image, default is
# 'absolute-paths'.
#
# @speed: #optional the maximum speed, in bytes per second
#
+# @bitmap: #optional the name of dirty bitmap if sync is "dirty-bitmap"
+# (Since 2.4)
+#
# @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).
@@ -715,7 +720,7 @@
{ 'type': 'DriveBackup',
'data': { 'device': 'str', 'target': 'str', '*format': 'str',
'sync': 'MirrorSyncMode', '*mode': 'NewImageMode',
- '*speed': 'int',
+ '*speed': 'int', '*bitmap': 'str',
'*on-source-error': 'BlockdevOnError',
'*on-target-error': 'BlockdevOnError' } }
diff --git a/qmp-commands.hx b/qmp-commands.hx
index e9f2eb1..cc77834 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -1074,7 +1074,7 @@ EQMP
{
.name = "drive-backup",
.args_type = "sync:s,device:B,target:s,speed:i?,mode:s?,format:s?,"
- "on-source-error:s?,on-target-error:s?",
+ "bitmap:s?,on-source-error:s?,on-target-error:s?",
.mhandler.cmd_new = qmp_marshal_input_drive_backup,
},
@@ -1101,8 +1101,9 @@ Arguments:
(json-string, optional)
- "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).
+ allocated in the topmost image, "dirty-bitmap" for only the dirty sectors in
+ the bitmap, or "none" to only replicate new I/O (MirrorSyncMode).
+- "bitmap": dirty bitmap name for sync==dirty-bitmap
- "mode": whether and how QEMU should create a new image
(NewImageMode, optional, default 'absolute-paths')
- "speed": the maximum speed, in bytes per second (json-int, optional)
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 10/20] qmp: Add support of "dirty-bitmap" sync mode for drive-backup
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 10/20] qmp: Add support of "dirty-bitmap" sync mode for drive-backup John Snow
@ 2015-04-02 12:44 ` Stefan Hajnoczi
2015-04-02 16:55 ` John Snow
2015-04-08 2:15 ` John Snow
0 siblings, 2 replies; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-02 12:44 UTC (permalink / raw)
To: John Snow
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
[-- Attachment #1: Type: text/plain, Size: 2475 bytes --]
On Fri, Mar 20, 2015 at 03:16:53PM -0400, John Snow wrote:
> + } else if (job->sync_mode == MIRROR_SYNC_MODE_DIRTY_BITMAP) {
> + /* Dirty Bitmap sync has a slightly different iteration method */
> + HBitmapIter hbi;
> + int64_t sector;
> + int64_t cluster;
> + int64_t last_cluster = -1;
> + bool polyrhythmic;
> +
> + bdrv_dirty_iter_init(bs, job->sync_bitmap, &hbi);
> + /* Does the granularity happen to match our backup cluster size? */
> + polyrhythmic = (bdrv_dirty_bitmap_granularity(job->sync_bitmap) !=
> + BACKUP_CLUSTER_SIZE);
> +
> + /* Find the next dirty /sector/ and copy that /cluster/ */
> + while ((sector = hbitmap_iter_next(&hbi)) != -1) {
> + cluster = sector / BACKUP_SECTORS_PER_CLUSTER;
> +
> + /* Fake progress updates for any clusters we skipped,
> + * excluding this current cluster. */
> + if (cluster != last_cluster + 1) {
> + job->common.offset += ((cluster - last_cluster - 1) *
> + BACKUP_CLUSTER_SIZE);
> + }
> +
> + if (yield_and_check(job)) {
> + goto leave;
> + }
> +
> + do {
> + ret = backup_do_cow(bs, cluster * BACKUP_SECTORS_PER_CLUSTER,
> + BACKUP_SECTORS_PER_CLUSTER, &error_is_read);
> + if ((ret < 0) &&
> + backup_error_action(job, error_is_read, -ret) ==
> + BLOCK_ERROR_ACTION_REPORT) {
> + goto leave;
> + }
> + } while (ret < 0);
> +
> + /* Advance (or rewind) our iterator if we need to. */
> + if (polyrhythmic) {
> + bdrv_set_dirty_iter(&hbi,
> + (cluster + 1) * BACKUP_SECTORS_PER_CLUSTER);
> + }
> +
> + last_cluster = cluster;
> + }
What happens when the dirty bitmap granularity is larger than
BACKUP_SECTORS_PER_CLUSTER?
|-----bitmap granularity-----|
|---backup cluster---|
~~~~~~~
Will these sectors ever be copied?
I think this case causes an infinite loop:
cluster = hbitmap_iter_next(&hbi) / BACKUP_SECTORS_PER_CLUSTER
The iterator is reset:
bdrv_set_dirty_iter(&hbi, (cluster + 1) * BACKUP_SECTORS_PER_CLUSTER);
So we get the same cluster ever time and never advance?
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 10/20] qmp: Add support of "dirty-bitmap" sync mode for drive-backup
2015-04-02 12:44 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
@ 2015-04-02 16:55 ` John Snow
2015-04-08 2:15 ` John Snow
1 sibling, 0 replies; 54+ messages in thread
From: John Snow @ 2015-04-02 16:55 UTC (permalink / raw)
To: Stefan Hajnoczi
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
On 04/02/2015 08:44 AM, Stefan Hajnoczi wrote:
> On Fri, Mar 20, 2015 at 03:16:53PM -0400, John Snow wrote:
>> + } else if (job->sync_mode == MIRROR_SYNC_MODE_DIRTY_BITMAP) {
>> + /* Dirty Bitmap sync has a slightly different iteration method */
>> + HBitmapIter hbi;
>> + int64_t sector;
>> + int64_t cluster;
>> + int64_t last_cluster = -1;
>> + bool polyrhythmic;
>> +
>> + bdrv_dirty_iter_init(bs, job->sync_bitmap, &hbi);
>> + /* Does the granularity happen to match our backup cluster size? */
>> + polyrhythmic = (bdrv_dirty_bitmap_granularity(job->sync_bitmap) !=
>> + BACKUP_CLUSTER_SIZE);
>> +
>> + /* Find the next dirty /sector/ and copy that /cluster/ */
>> + while ((sector = hbitmap_iter_next(&hbi)) != -1) {
>> + cluster = sector / BACKUP_SECTORS_PER_CLUSTER;
>> +
>> + /* Fake progress updates for any clusters we skipped,
>> + * excluding this current cluster. */
>> + if (cluster != last_cluster + 1) {
>> + job->common.offset += ((cluster - last_cluster - 1) *
>> + BACKUP_CLUSTER_SIZE);
>> + }
>> +
>> + if (yield_and_check(job)) {
>> + goto leave;
>> + }
>> +
>> + do {
>> + ret = backup_do_cow(bs, cluster * BACKUP_SECTORS_PER_CLUSTER,
>> + BACKUP_SECTORS_PER_CLUSTER, &error_is_read);
>> + if ((ret < 0) &&
>> + backup_error_action(job, error_is_read, -ret) ==
>> + BLOCK_ERROR_ACTION_REPORT) {
>> + goto leave;
>> + }
>> + } while (ret < 0);
>> +
>> + /* Advance (or rewind) our iterator if we need to. */
>> + if (polyrhythmic) {
>> + bdrv_set_dirty_iter(&hbi,
>> + (cluster + 1) * BACKUP_SECTORS_PER_CLUSTER);
>> + }
>> +
>> + last_cluster = cluster;
>> + }
>
> What happens when the dirty bitmap granularity is larger than
> BACKUP_SECTORS_PER_CLUSTER?
>
> |-----bitmap granularity-----|
> |---backup cluster---|
> ~~~~~~~
> Will these sectors ever be copied?
>
> I think this case causes an infinite loop:
>
> cluster = hbitmap_iter_next(&hbi) / BACKUP_SECTORS_PER_CLUSTER
>
> The iterator is reset:
>
> bdrv_set_dirty_iter(&hbi, (cluster + 1) * BACKUP_SECTORS_PER_CLUSTER);
>
> So we get the same cluster ever time and never advance?
>
That is indeed a bug. Tracking to the middle of a granularity group will
return the index of the group you're in the middle of, not the next group.
Thanks for catching this.
^ permalink raw reply [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 10/20] qmp: Add support of "dirty-bitmap" sync mode for drive-backup
2015-04-02 12:44 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2015-04-02 16:55 ` John Snow
@ 2015-04-08 2:15 ` John Snow
1 sibling, 0 replies; 54+ messages in thread
From: John Snow @ 2015-04-08 2:15 UTC (permalink / raw)
To: Stefan Hajnoczi
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
On 04/02/2015 08:44 AM, Stefan Hajnoczi wrote:
> On Fri, Mar 20, 2015 at 03:16:53PM -0400, John Snow wrote:
>> + } else if (job->sync_mode == MIRROR_SYNC_MODE_DIRTY_BITMAP) {
>> + /* Dirty Bitmap sync has a slightly different iteration method */
>> + HBitmapIter hbi;
>> + int64_t sector;
>> + int64_t cluster;
>> + int64_t last_cluster = -1;
>> + bool polyrhythmic;
>> +
>> + bdrv_dirty_iter_init(bs, job->sync_bitmap, &hbi);
>> + /* Does the granularity happen to match our backup cluster size? */
>> + polyrhythmic = (bdrv_dirty_bitmap_granularity(job->sync_bitmap) !=
>> + BACKUP_CLUSTER_SIZE);
>> +
>> + /* Find the next dirty /sector/ and copy that /cluster/ */
>> + while ((sector = hbitmap_iter_next(&hbi)) != -1) {
>> + cluster = sector / BACKUP_SECTORS_PER_CLUSTER;
>> +
>> + /* Fake progress updates for any clusters we skipped,
>> + * excluding this current cluster. */
>> + if (cluster != last_cluster + 1) {
>> + job->common.offset += ((cluster - last_cluster - 1) *
>> + BACKUP_CLUSTER_SIZE);
>> + }
>> +
>> + if (yield_and_check(job)) {
>> + goto leave;
>> + }
>> +
>> + do {
>> + ret = backup_do_cow(bs, cluster * BACKUP_SECTORS_PER_CLUSTER,
>> + BACKUP_SECTORS_PER_CLUSTER, &error_is_read);
>> + if ((ret < 0) &&
>> + backup_error_action(job, error_is_read, -ret) ==
>> + BLOCK_ERROR_ACTION_REPORT) {
>> + goto leave;
>> + }
>> + } while (ret < 0);
>> +
>> + /* Advance (or rewind) our iterator if we need to. */
>> + if (polyrhythmic) {
>> + bdrv_set_dirty_iter(&hbi,
>> + (cluster + 1) * BACKUP_SECTORS_PER_CLUSTER);
>> + }
>> +
>> + last_cluster = cluster;
>> + }
>
> What happens when the dirty bitmap granularity is larger than
> BACKUP_SECTORS_PER_CLUSTER?
>
> |-----bitmap granularity-----|
> |---backup cluster---|
> ~~~~~~~
> Will these sectors ever be copied?
>
> I think this case causes an infinite loop:
>
> cluster = hbitmap_iter_next(&hbi) / BACKUP_SECTORS_PER_CLUSTER
>
> The iterator is reset:
>
> bdrv_set_dirty_iter(&hbi, (cluster + 1) * BACKUP_SECTORS_PER_CLUSTER);
>
> So we get the same cluster ever time and never advance?
>
I had mistakenly thought that if I advanced to the middle of a
granularity grouping that the iterator might return the next (virtual)
index to me, instead of the beginning of the current group.
Anyway, I've fixed this up a bit and added in some granularity variance
tests for the iotests to test what happens if the granularity is larger,
equal, or smaller.
v5 is ready to send out, but I need to test it first, so I will probably
send that out Wednesday night.
Thanks,
--js
^ permalink raw reply [flat|nested] 54+ messages in thread
* [Qemu-devel] [PATCH v4 11/20] qmp: add block-dirty-bitmap-clear
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (9 preceding siblings ...)
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 10/20] qmp: Add support of "dirty-bitmap" sync mode for drive-backup John Snow
@ 2015-03-20 19:16 ` John Snow
2015-04-02 12:49 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 12/20] qmp: Add dirty bitmap status field in query-block John Snow
` (10 subsequent siblings)
21 siblings, 1 reply; 54+ messages in thread
From: John Snow @ 2015-03-20 19:16 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
Add bdrv_clear_dirty_bitmap and a matching QMP command,
qmp_block_dirty_bitmap_clear that enables a user to reset
the bitmap attached to a drive.
This allows us to reset a bitmap in the event of a full
drive backup.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
block.c | 8 ++++++++
blockdev.c | 34 ++++++++++++++++++++++++++++++++++
include/block/block.h | 1 +
qapi/block-core.json | 14 ++++++++++++++
qmp-commands.hx | 29 +++++++++++++++++++++++++++++
5 files changed, 86 insertions(+)
diff --git a/block.c b/block.c
index 63cdedf..a4b3e34 100644
--- a/block.c
+++ b/block.c
@@ -62,6 +62,7 @@
struct BdrvDirtyBitmap {
HBitmap *bitmap;
BdrvDirtyBitmap *successor;
+ int64_t size;
char *name;
bool disabled;
QLIST_ENTRY(BdrvDirtyBitmap) list;
@@ -5458,6 +5459,7 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
}
bitmap = g_new0(BdrvDirtyBitmap, 1);
bitmap->bitmap = hbitmap_alloc(bitmap_size, ffs(sector_granularity) - 1);
+ bitmap->size = bitmap_size;
bitmap->name = g_strdup(name);
bitmap->disabled = false;
QLIST_INSERT_HEAD(&bs->dirty_bitmaps, bitmap, list);
@@ -5660,6 +5662,12 @@ void bdrv_reset_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
hbitmap_reset(bitmap->bitmap, cur_sector, nr_sectors);
}
+void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap)
+{
+ assert(bdrv_dirty_bitmap_enabled(bitmap));
+ hbitmap_reset(bitmap->bitmap, 0, bitmap->size);
+}
+
static void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector,
int nr_sectors)
{
diff --git a/blockdev.c b/blockdev.c
index 90ba5b6..df96959 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -2078,6 +2078,40 @@ void qmp_block_dirty_bitmap_remove(const char *node, const char *name,
aio_context_release(aio_context);
}
+/**
+ * Completely clear a bitmap, for the purposes of synchronizing a bitmap
+ * immediately after a full backup operation.
+ */
+void qmp_block_dirty_bitmap_clear(const char *node, const char *name,
+ Error **errp)
+{
+ AioContext *aio_context;
+ BdrvDirtyBitmap *bitmap;
+ BlockDriverState *bs;
+
+ bitmap = block_dirty_bitmap_lookup(node, name, &bs, &aio_context, errp);
+ if (!bitmap || !bs) {
+ return;
+ }
+
+ if (bdrv_dirty_bitmap_frozen(bitmap)) {
+ error_setg(errp,
+ "Bitmap '%s' is currently frozen and cannot be modified",
+ name);
+ goto out;
+ } else if (!bdrv_dirty_bitmap_enabled(bitmap)) {
+ error_setg(errp,
+ "Bitmap '%s' is currently disabled and cannot be cleared",
+ name);
+ goto out;
+ }
+
+ bdrv_clear_dirty_bitmap(bitmap);
+
+ out:
+ aio_context_release(aio_context);
+}
+
int hmp_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data)
{
const char *id = qdict_get_str(qdict, "id");
diff --git a/include/block/block.h b/include/block/block.h
index 80ac2cc..0961b1e 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -478,6 +478,7 @@ void bdrv_set_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int nr_sectors);
void bdrv_reset_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int nr_sectors);
+void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap);
void bdrv_dirty_iter_init(BlockDriverState *bs,
BdrvDirtyBitmap *bitmap, struct HBitmapIter *hbi);
void bdrv_set_dirty_iter(struct HBitmapIter *hbi, int64_t offset);
diff --git a/qapi/block-core.json b/qapi/block-core.json
index c17a7e9..dbcf25a 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -1021,6 +1021,20 @@
'data': 'BlockDirtyBitmap' }
##
+# @block-dirty-bitmap-clear
+#
+# Clear (reset) a dirty bitmap on the device
+#
+# Returns: nothing on success
+# If @node is not a valid block device, DeviceNotFound
+# If @name is not found, GenericError with an explanation
+#
+# Since 2.4
+##
+{ 'command': 'block-dirty-bitmap-clear',
+ 'data': 'BlockDirtyBitmap' }
+
+##
# @block_set_io_throttle:
#
# Change I/O throttle limits for a block drive.
diff --git a/qmp-commands.hx b/qmp-commands.hx
index cc77834..11ddb44 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -1327,6 +1327,35 @@ Example:
EQMP
{
+ .name = "block-dirty-bitmap-clear",
+ .args_type = "node:B,name:s",
+ .mhandler.cmd_new = qmp_marshal_input_block_dirty_bitmap_clear,
+ },
+
+SQMP
+
+block-dirty-bitmap-clear
+------------------------
+Since 2.4
+
+Reset the dirty bitmap associated with a node so that an incremental backup
+from this point in time forward will only backup clusters modified after this
+clear operation.
+
+Arguments:
+
+- "node": device/node on which to remove dirty bitmap (json-string)
+- "name": name of the dirty bitmap to remove (json-string)
+
+Example:
+
+-> { "execute": "block-dirty-bitmap-clear", "arguments": { "node": "drive0",
+ "name": "bitmap0" } }
+<- { "return": {} }
+
+EQMP
+
+ {
.name = "blockdev-snapshot-sync",
.args_type = "device:s?,node-name:s?,snapshot-file:s,snapshot-node-name:s?,format:s?,mode:s?",
.mhandler.cmd_new = qmp_marshal_input_blockdev_snapshot_sync,
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 11/20] qmp: add block-dirty-bitmap-clear
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 11/20] qmp: add block-dirty-bitmap-clear John Snow
@ 2015-04-02 12:49 ` Stefan Hajnoczi
0 siblings, 0 replies; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-02 12:49 UTC (permalink / raw)
To: John Snow
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
[-- Attachment #1: Type: text/plain, Size: 737 bytes --]
On Fri, Mar 20, 2015 at 03:16:54PM -0400, John Snow wrote:
> Add bdrv_clear_dirty_bitmap and a matching QMP command,
> qmp_block_dirty_bitmap_clear that enables a user to reset
> the bitmap attached to a drive.
>
> This allows us to reset a bitmap in the event of a full
> drive backup.
>
> Signed-off-by: John Snow <jsnow@redhat.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
> ---
> block.c | 8 ++++++++
> blockdev.c | 34 ++++++++++++++++++++++++++++++++++
> include/block/block.h | 1 +
> qapi/block-core.json | 14 ++++++++++++++
> qmp-commands.hx | 29 +++++++++++++++++++++++++++++
> 5 files changed, 86 insertions(+)
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread
* [Qemu-devel] [PATCH v4 12/20] qmp: Add dirty bitmap status field in query-block
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (10 preceding siblings ...)
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 11/20] qmp: add block-dirty-bitmap-clear John Snow
@ 2015-03-20 19:16 ` John Snow
2015-04-02 12:49 ` Stefan Hajnoczi
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 13/20] block: add BdrvDirtyBitmap documentation John Snow
` (9 subsequent siblings)
21 siblings, 1 reply; 54+ messages in thread
From: John Snow @ 2015-03-20 19:16 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
Add the "frozen" status booleans, to inform clients
when a bitmap is occupied doing a task.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
block.c | 1 +
qapi/block-core.json | 5 ++++-
2 files changed, 5 insertions(+), 1 deletion(-)
diff --git a/block.c b/block.c
index a4b3e34..005b535 100644
--- a/block.c
+++ b/block.c
@@ -5600,6 +5600,7 @@ BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs)
info->granularity = bdrv_dirty_bitmap_granularity(bm);
info->has_name = !!bm->name;
info->name = g_strdup(bm->name);
+ info->frozen = bdrv_dirty_bitmap_frozen(bm);
entry->value = info;
*plist = entry;
plist = &entry->next;
diff --git a/qapi/block-core.json b/qapi/block-core.json
index dbcf25a..e57b116 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -336,10 +336,13 @@
#
# @granularity: granularity of the dirty bitmap in bytes (since 1.4)
#
+# @frozen: whether the dirty bitmap is frozen (Since 2.4)
+#
# Since: 1.3
##
{ 'type': 'BlockDirtyInfo',
- 'data': {'*name': 'str', 'count': 'int', 'granularity': 'uint32'} }
+ 'data': {'*name': 'str', 'count': 'int', 'granularity': 'uint32',
+ 'frozen': 'bool'} }
##
# @BlockInfo:
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [PATCH v4 12/20] qmp: Add dirty bitmap status field in query-block
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 12/20] qmp: Add dirty bitmap status field in query-block John Snow
@ 2015-04-02 12:49 ` Stefan Hajnoczi
0 siblings, 0 replies; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-02 12:49 UTC (permalink / raw)
To: John Snow
Cc: kwolf, famz, qemu-block, qemu-devel, armbru, vsementsov,
stefanha, mreitz
[-- Attachment #1: Type: text/plain, Size: 480 bytes --]
On Fri, Mar 20, 2015 at 03:16:55PM -0400, John Snow wrote:
> Add the "frozen" status booleans, to inform clients
> when a bitmap is occupied doing a task.
>
> Signed-off-by: Fam Zheng <famz@redhat.com>
> Signed-off-by: John Snow <jsnow@redhat.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
> ---
> block.c | 1 +
> qapi/block-core.json | 5 ++++-
> 2 files changed, 5 insertions(+), 1 deletion(-)
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread
* [Qemu-devel] [PATCH v4 13/20] block: add BdrvDirtyBitmap documentation
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (11 preceding siblings ...)
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 12/20] qmp: Add dirty bitmap status field in query-block John Snow
@ 2015-03-20 19:16 ` John Snow
2015-04-02 12:50 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 14/20] block: Ensure consistent bitmap function prototypes John Snow
` (8 subsequent siblings)
21 siblings, 1 reply; 54+ messages in thread
From: John Snow @ 2015-03-20 19:16 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
block.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/block.c b/block.c
index 005b535..c2e1b27 100644
--- a/block.c
+++ b/block.c
@@ -60,11 +60,11 @@
* or enabled. A frozen bitmap can only abdicate() or reclaim().
*/
struct BdrvDirtyBitmap {
- HBitmap *bitmap;
- BdrvDirtyBitmap *successor;
- int64_t size;
- char *name;
- bool disabled;
+ HBitmap *bitmap; /* Dirty sector bitmap implementation */
+ BdrvDirtyBitmap *successor; /* Anonymous child; implies frozen status */
+ char *name; /* Optional non-empty unique ID */
+ int64_t size; /* Size of the bitmap (Number of sectors) */
+ bool disabled; /* Bitmap is read-only */
QLIST_ENTRY(BdrvDirtyBitmap) list;
};
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 13/20] block: add BdrvDirtyBitmap documentation
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 13/20] block: add BdrvDirtyBitmap documentation John Snow
@ 2015-04-02 12:50 ` Stefan Hajnoczi
0 siblings, 0 replies; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-02 12:50 UTC (permalink / raw)
To: John Snow
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
[-- Attachment #1: Type: text/plain, Size: 286 bytes --]
On Fri, Mar 20, 2015 at 03:16:56PM -0400, John Snow wrote:
> Signed-off-by: John Snow <jsnow@redhat.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
> ---
> block.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread
* [Qemu-devel] [PATCH v4 14/20] block: Ensure consistent bitmap function prototypes
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (12 preceding siblings ...)
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 13/20] block: add BdrvDirtyBitmap documentation John Snow
@ 2015-03-20 19:16 ` John Snow
2015-04-02 12:50 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 15/20] block: Resize bitmaps on bdrv_truncate John Snow
` (7 subsequent siblings)
21 siblings, 1 reply; 54+ messages in thread
From: John Snow @ 2015-03-20 19:16 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
We often don't need the BlockDriverState for functions
that operate on bitmaps. Remove it.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
block.c | 13 ++++++-------
block/backup.c | 2 +-
block/mirror.c | 26 ++++++++++----------------
blockdev.c | 2 +-
include/block/block.h | 11 +++++------
migration/block.c | 7 +++----
6 files changed, 26 insertions(+), 35 deletions(-)
diff --git a/block.c b/block.c
index c2e1b27..81d176a 100644
--- a/block.c
+++ b/block.c
@@ -5427,7 +5427,7 @@ BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs, const char *name)
return NULL;
}
-void bdrv_dirty_bitmap_make_anon(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
+void bdrv_dirty_bitmap_make_anon(BdrvDirtyBitmap *bitmap)
{
assert(!bdrv_dirty_bitmap_frozen(bitmap));
g_free(bitmap->name);
@@ -5596,7 +5596,7 @@ BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs)
QLIST_FOREACH(bm, &bs->dirty_bitmaps, list) {
BlockDirtyInfo *info = g_new0(BlockDirtyInfo, 1);
BlockDirtyInfoList *entry = g_new0(BlockDirtyInfoList, 1);
- info->count = bdrv_get_dirty_count(bs, bm);
+ info->count = bdrv_get_dirty_count(bm);
info->granularity = bdrv_dirty_bitmap_granularity(bm);
info->has_name = !!bm->name;
info->name = g_strdup(bm->name);
@@ -5643,20 +5643,19 @@ uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap)
return BDRV_SECTOR_SIZE << hbitmap_granularity(bitmap->bitmap);
}
-void bdrv_dirty_iter_init(BlockDriverState *bs,
- BdrvDirtyBitmap *bitmap, HBitmapIter *hbi)
+void bdrv_dirty_iter_init(BdrvDirtyBitmap *bitmap, HBitmapIter *hbi)
{
hbitmap_iter_init(hbi, bitmap->bitmap, 0);
}
-void bdrv_set_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
+void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int nr_sectors)
{
assert(bdrv_dirty_bitmap_enabled(bitmap));
hbitmap_set(bitmap->bitmap, cur_sector, nr_sectors);
}
-void bdrv_reset_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
+void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int nr_sectors)
{
assert(bdrv_dirty_bitmap_enabled(bitmap));
@@ -5702,7 +5701,7 @@ void bdrv_set_dirty_iter(HBitmapIter *hbi, int64_t offset)
hbitmap_iter_init(hbi, hbi->hb, offset);
}
-int64_t bdrv_get_dirty_count(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
+int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap)
{
return hbitmap_count(bitmap->bitmap);
}
diff --git a/block/backup.c b/block/backup.c
index 2639ba8..4f9a3de 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -313,7 +313,7 @@ static void coroutine_fn backup_run(void *opaque)
int64_t last_cluster = -1;
bool polyrhythmic;
- bdrv_dirty_iter_init(bs, job->sync_bitmap, &hbi);
+ bdrv_dirty_iter_init(job->sync_bitmap, &hbi);
/* Does the granularity happen to match our backup cluster size? */
polyrhythmic = (bdrv_dirty_bitmap_granularity(job->sync_bitmap) !=
BACKUP_CLUSTER_SIZE);
diff --git a/block/mirror.c b/block/mirror.c
index f89eccf..dcd6f65 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -125,11 +125,9 @@ static void mirror_write_complete(void *opaque, int ret)
MirrorOp *op = opaque;
MirrorBlockJob *s = op->s;
if (ret < 0) {
- BlockDriverState *source = s->common.bs;
BlockErrorAction action;
- bdrv_set_dirty_bitmap(source, s->dirty_bitmap, op->sector_num,
- op->nb_sectors);
+ bdrv_set_dirty_bitmap(s->dirty_bitmap, op->sector_num, op->nb_sectors);
action = mirror_error_action(s, false, -ret);
if (action == BLOCK_ERROR_ACTION_REPORT && s->ret >= 0) {
s->ret = ret;
@@ -143,11 +141,9 @@ static void mirror_read_complete(void *opaque, int ret)
MirrorOp *op = opaque;
MirrorBlockJob *s = op->s;
if (ret < 0) {
- BlockDriverState *source = s->common.bs;
BlockErrorAction action;
- bdrv_set_dirty_bitmap(source, s->dirty_bitmap, op->sector_num,
- op->nb_sectors);
+ bdrv_set_dirty_bitmap(s->dirty_bitmap, op->sector_num, op->nb_sectors);
action = mirror_error_action(s, true, -ret);
if (action == BLOCK_ERROR_ACTION_REPORT && s->ret >= 0) {
s->ret = ret;
@@ -170,10 +166,9 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)
s->sector_num = hbitmap_iter_next(&s->hbi);
if (s->sector_num < 0) {
- bdrv_dirty_iter_init(source, s->dirty_bitmap, &s->hbi);
+ bdrv_dirty_iter_init(s->dirty_bitmap, &s->hbi);
s->sector_num = hbitmap_iter_next(&s->hbi);
- trace_mirror_restart_iter(s,
- bdrv_get_dirty_count(source, s->dirty_bitmap));
+ trace_mirror_restart_iter(s, bdrv_get_dirty_count(s->dirty_bitmap));
assert(s->sector_num >= 0);
}
@@ -288,8 +283,7 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)
next_sector += sectors_per_chunk;
}
- bdrv_reset_dirty_bitmap(source, s->dirty_bitmap, sector_num,
- nb_sectors);
+ bdrv_reset_dirty_bitmap(s->dirty_bitmap, sector_num, nb_sectors);
/* Copy the dirty cluster. */
s->in_flight++;
@@ -446,7 +440,7 @@ static void coroutine_fn mirror_run(void *opaque)
assert(n > 0);
if (ret == 1) {
- bdrv_set_dirty_bitmap(bs, s->dirty_bitmap, sector_num, n);
+ bdrv_set_dirty_bitmap(s->dirty_bitmap, sector_num, n);
sector_num = next;
} else {
sector_num += n;
@@ -454,7 +448,7 @@ static void coroutine_fn mirror_run(void *opaque)
}
}
- bdrv_dirty_iter_init(bs, s->dirty_bitmap, &s->hbi);
+ bdrv_dirty_iter_init(s->dirty_bitmap, &s->hbi);
last_pause_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
for (;;) {
uint64_t delay_ns = 0;
@@ -466,7 +460,7 @@ static void coroutine_fn mirror_run(void *opaque)
goto immediate_exit;
}
- cnt = bdrv_get_dirty_count(bs, s->dirty_bitmap);
+ cnt = bdrv_get_dirty_count(s->dirty_bitmap);
/* s->common.offset contains the number of bytes already processed so
* far, cnt is the number of dirty sectors remaining and
* s->sectors_in_flight is the number of sectors currently being
@@ -516,7 +510,7 @@ static void coroutine_fn mirror_run(void *opaque)
should_complete = s->should_complete ||
block_job_is_cancelled(&s->common);
- cnt = bdrv_get_dirty_count(bs, s->dirty_bitmap);
+ cnt = bdrv_get_dirty_count(s->dirty_bitmap);
}
}
@@ -531,7 +525,7 @@ static void coroutine_fn mirror_run(void *opaque)
*/
trace_mirror_before_drain(s, cnt);
bdrv_drain(bs);
- cnt = bdrv_get_dirty_count(bs, s->dirty_bitmap);
+ cnt = bdrv_get_dirty_count(s->dirty_bitmap);
}
ret = 0;
diff --git a/blockdev.c b/blockdev.c
index df96959..b9c79ed 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -2071,7 +2071,7 @@ void qmp_block_dirty_bitmap_remove(const char *node, const char *name,
name);
goto out;
}
- bdrv_dirty_bitmap_make_anon(bs, bitmap);
+ bdrv_dirty_bitmap_make_anon(bitmap);
bdrv_release_dirty_bitmap(bs, bitmap);
out:
diff --git a/include/block/block.h b/include/block/block.h
index 0961b1e..36bdf04 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -464,7 +464,7 @@ BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs,
Error **errp);
BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs,
const char *name);
-void bdrv_dirty_bitmap_make_anon(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
+void bdrv_dirty_bitmap_make_anon(BdrvDirtyBitmap *bitmap);
void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
void bdrv_disable_dirty_bitmap(BdrvDirtyBitmap *bitmap);
void bdrv_enable_dirty_bitmap(BdrvDirtyBitmap *bitmap);
@@ -474,15 +474,14 @@ uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap);
bool bdrv_dirty_bitmap_enabled(BdrvDirtyBitmap *bitmap);
bool bdrv_dirty_bitmap_frozen(BdrvDirtyBitmap *bitmap);
int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, int64_t sector);
-void bdrv_set_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
+void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int nr_sectors);
-void bdrv_reset_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
+void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
int64_t cur_sector, int nr_sectors);
void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap);
-void bdrv_dirty_iter_init(BlockDriverState *bs,
- BdrvDirtyBitmap *bitmap, struct HBitmapIter *hbi);
+void bdrv_dirty_iter_init(BdrvDirtyBitmap *bitmap, struct HBitmapIter *hbi);
void bdrv_set_dirty_iter(struct HBitmapIter *hbi, int64_t offset);
-int64_t bdrv_get_dirty_count(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
+int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap);
void bdrv_enable_copy_on_read(BlockDriverState *bs);
void bdrv_disable_copy_on_read(BlockDriverState *bs);
diff --git a/migration/block.c b/migration/block.c
index 02a7d26..ddb59cc 100644
--- a/migration/block.c
+++ b/migration/block.c
@@ -304,7 +304,7 @@ static int mig_save_device_bulk(QEMUFile *f, BlkMigDevState *bmds)
blk->aiocb = bdrv_aio_readv(bs, cur_sector, &blk->qiov,
nr_sectors, blk_mig_read_cb, blk);
- bdrv_reset_dirty_bitmap(bs, bmds->dirty_bitmap, cur_sector, nr_sectors);
+ bdrv_reset_dirty_bitmap(bmds->dirty_bitmap, cur_sector, nr_sectors);
qemu_mutex_unlock_iothread();
bmds->cur_sector = cur_sector + nr_sectors;
@@ -497,8 +497,7 @@ static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds,
g_free(blk);
}
- bdrv_reset_dirty_bitmap(bmds->bs, bmds->dirty_bitmap, sector,
- nr_sectors);
+ bdrv_reset_dirty_bitmap(bmds->dirty_bitmap, sector, nr_sectors);
break;
}
sector += BDRV_SECTORS_PER_DIRTY_CHUNK;
@@ -584,7 +583,7 @@ static int64_t get_remaining_dirty(void)
int64_t dirty = 0;
QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
- dirty += bdrv_get_dirty_count(bmds->bs, bmds->dirty_bitmap);
+ dirty += bdrv_get_dirty_count(bmds->dirty_bitmap);
}
return dirty << BDRV_SECTOR_BITS;
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 14/20] block: Ensure consistent bitmap function prototypes
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 14/20] block: Ensure consistent bitmap function prototypes John Snow
@ 2015-04-02 12:50 ` Stefan Hajnoczi
0 siblings, 0 replies; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-02 12:50 UTC (permalink / raw)
To: John Snow
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
[-- Attachment #1: Type: text/plain, Size: 623 bytes --]
On Fri, Mar 20, 2015 at 03:16:57PM -0400, John Snow wrote:
> We often don't need the BlockDriverState for functions
> that operate on bitmaps. Remove it.
>
> Signed-off-by: John Snow <jsnow@redhat.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
> ---
> block.c | 13 ++++++-------
> block/backup.c | 2 +-
> block/mirror.c | 26 ++++++++++----------------
> blockdev.c | 2 +-
> include/block/block.h | 11 +++++------
> migration/block.c | 7 +++----
> 6 files changed, 26 insertions(+), 35 deletions(-)
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread
* [Qemu-devel] [PATCH v4 15/20] block: Resize bitmaps on bdrv_truncate
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (13 preceding siblings ...)
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 14/20] block: Ensure consistent bitmap function prototypes John Snow
@ 2015-03-20 19:16 ` John Snow
2015-04-02 13:37 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 16/20] hbitmap: truncate tests John Snow
` (6 subsequent siblings)
21 siblings, 1 reply; 54+ messages in thread
From: John Snow @ 2015-03-20 19:16 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
block.c | 18 +++++++++++++++++
include/qemu/hbitmap.h | 10 ++++++++++
util/hbitmap.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 80 insertions(+)
diff --git a/block.c b/block.c
index 81d176a..9a8f2da 100644
--- a/block.c
+++ b/block.c
@@ -113,6 +113,7 @@ static void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector,
int nr_sectors);
static void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector,
int nr_sectors);
+static void bdrv_dirty_bitmap_truncate(BlockDriverState *bs);
/* If non-zero, use only whitelisted block drivers */
static int use_bdrv_whitelist;
@@ -3550,6 +3551,7 @@ int bdrv_truncate(BlockDriverState *bs, int64_t offset)
ret = drv->bdrv_truncate(bs, offset);
if (ret == 0) {
ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);
+ bdrv_dirty_bitmap_truncate(bs);
if (bs->blk) {
blk_dev_resize_cb(bs->blk);
}
@@ -5560,6 +5562,22 @@ BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs,
return parent;
}
+/**
+ * Truncates _all_ bitmaps attached to a BDS.
+ */
+static void bdrv_dirty_bitmap_truncate(BlockDriverState *bs)
+{
+ BdrvDirtyBitmap *bitmap;
+ uint64_t size = bdrv_nb_sectors(bs);
+
+ QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
+ if (bdrv_dirty_bitmap_frozen(bitmap)) {
+ continue;
+ }
+ hbitmap_truncate(bitmap->bitmap, size);
+ }
+}
+
void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
{
BdrvDirtyBitmap *bm, *next;
diff --git a/include/qemu/hbitmap.h b/include/qemu/hbitmap.h
index c19c1cb..a75157e 100644
--- a/include/qemu/hbitmap.h
+++ b/include/qemu/hbitmap.h
@@ -65,6 +65,16 @@ struct HBitmapIter {
HBitmap *hbitmap_alloc(uint64_t size, int granularity);
/**
+ * hbitmap_truncate:
+ * @hb: The bitmap to change the size of.
+ * @size: The number of elements to change the bitmap to accommodate.
+ *
+ * truncate or grow an existing bitmap to accommodate a new number of elements.
+ * This may invalidate existing HBitmapIterators.
+ */
+void hbitmap_truncate(HBitmap *hb, uint64_t size);
+
+/**
* hbitmap_merge:
* @a: The bitmap to store the result in.
* @b: The bitmap to merge into @a.
diff --git a/util/hbitmap.c b/util/hbitmap.c
index ba11fd3..4505ef7 100644
--- a/util/hbitmap.c
+++ b/util/hbitmap.c
@@ -400,6 +400,58 @@ HBitmap *hbitmap_alloc(uint64_t size, int granularity)
return hb;
}
+void hbitmap_truncate(HBitmap *hb, uint64_t size)
+{
+ bool shrink;
+ unsigned i;
+ uint64_t num_elements = size;
+ uint64_t old;
+
+ /* Size comes in as logical elements, adjust for granularity. */
+ size = (size + (1ULL << hb->granularity) - 1) >> hb->granularity;
+ assert(size <= ((uint64_t)1 << HBITMAP_LOG_MAX_SIZE));
+ shrink = size < hb->size;
+
+ /* bit sizes are identical; nothing to do. */
+ if (size == hb->size) {
+ return;
+ }
+
+ /* If we're losing bits, let's clear those bits before we invalidate all of
+ * our invariants. This helps keep the bitcount consistent, and will prevent
+ * us from carrying around garbage bits beyond the end of the map.
+ *
+ * Because clearing bits past the end of map might reset bits we care about
+ * within the array, record the current value of the last bit we're keeping.
+ */
+ if (shrink) {
+ bool set = hbitmap_get(hb, num_elements - 1);
+ uint64_t fix_count = (hb->size << hb->granularity) - num_elements;
+
+ assert(fix_count);
+ hbitmap_reset(hb, num_elements, fix_count);
+ if (set) {
+ hbitmap_set(hb, num_elements - 1, 1);
+ }
+ }
+
+ hb->size = size;
+ for (i = HBITMAP_LEVELS; i-- > 0; ) {
+ size = MAX(BITS_TO_LONGS(size), 1);
+ if (hb->sizes[i] == size) {
+ break;
+ }
+ old = hb->sizes[i];
+ hb->sizes[i] = size;
+ hb->levels[i] = g_realloc(hb->levels[i], size * sizeof(unsigned long));
+ if (!shrink) {
+ memset(&hb->levels[i][old], 0x00,
+ (size - old) * sizeof(*hb->levels[i]));
+ }
+ }
+}
+
+
/**
* Given HBitmaps A and B, let A := A (BITOR) B.
* Bitmap B will not be modified.
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 15/20] block: Resize bitmaps on bdrv_truncate
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 15/20] block: Resize bitmaps on bdrv_truncate John Snow
@ 2015-04-02 13:37 ` Stefan Hajnoczi
2015-04-02 15:57 ` John Snow
0 siblings, 1 reply; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-02 13:37 UTC (permalink / raw)
To: John Snow
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
[-- Attachment #1: Type: text/plain, Size: 1430 bytes --]
On Fri, Mar 20, 2015 at 03:16:58PM -0400, John Snow wrote:
> +void hbitmap_truncate(HBitmap *hb, uint64_t size)
> +{
> + bool shrink;
> + unsigned i;
> + uint64_t num_elements = size;
> + uint64_t old;
> +
> + /* Size comes in as logical elements, adjust for granularity. */
> + size = (size + (1ULL << hb->granularity) - 1) >> hb->granularity;
> + assert(size <= ((uint64_t)1 << HBITMAP_LOG_MAX_SIZE));
> + shrink = size < hb->size;
> +
> + /* bit sizes are identical; nothing to do. */
> + if (size == hb->size) {
> + return;
> + }
> +
> + /* If we're losing bits, let's clear those bits before we invalidate all of
> + * our invariants. This helps keep the bitcount consistent, and will prevent
> + * us from carrying around garbage bits beyond the end of the map.
> + *
> + * Because clearing bits past the end of map might reset bits we care about
> + * within the array, record the current value of the last bit we're keeping.
> + */
> + if (shrink) {
> + bool set = hbitmap_get(hb, num_elements - 1);
> + uint64_t fix_count = (hb->size << hb->granularity) - num_elements;
> +
> + assert(fix_count);
> + hbitmap_reset(hb, num_elements, fix_count);
> + if (set) {
> + hbitmap_set(hb, num_elements - 1, 1);
> + }
Why is it necessary to set the last bit (if it was set)? The comment
isn't clear to me.
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^ permalink raw reply [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 15/20] block: Resize bitmaps on bdrv_truncate
2015-04-02 13:37 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
@ 2015-04-02 15:57 ` John Snow
2015-04-07 12:57 ` Stefan Hajnoczi
0 siblings, 1 reply; 54+ messages in thread
From: John Snow @ 2015-04-02 15:57 UTC (permalink / raw)
To: Stefan Hajnoczi
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
On 04/02/2015 09:37 AM, Stefan Hajnoczi wrote:
> On Fri, Mar 20, 2015 at 03:16:58PM -0400, John Snow wrote:
>> +void hbitmap_truncate(HBitmap *hb, uint64_t size)
>> +{
>> + bool shrink;
>> + unsigned i;
>> + uint64_t num_elements = size;
>> + uint64_t old;
>> +
>> + /* Size comes in as logical elements, adjust for granularity. */
>> + size = (size + (1ULL << hb->granularity) - 1) >> hb->granularity;
>> + assert(size <= ((uint64_t)1 << HBITMAP_LOG_MAX_SIZE));
>> + shrink = size < hb->size;
>> +
>> + /* bit sizes are identical; nothing to do. */
>> + if (size == hb->size) {
>> + return;
>> + }
>> +
>> + /* If we're losing bits, let's clear those bits before we invalidate all of
>> + * our invariants. This helps keep the bitcount consistent, and will prevent
>> + * us from carrying around garbage bits beyond the end of the map.
>> + *
>> + * Because clearing bits past the end of map might reset bits we care about
>> + * within the array, record the current value of the last bit we're keeping.
>> + */
>> + if (shrink) {
>> + bool set = hbitmap_get(hb, num_elements - 1);
>> + uint64_t fix_count = (hb->size << hb->granularity) - num_elements;
>> +
>> + assert(fix_count);
>> + hbitmap_reset(hb, num_elements, fix_count);
>> + if (set) {
>> + hbitmap_set(hb, num_elements - 1, 1);
>> + }
>
> Why is it necessary to set the last bit (if it was set)? The comment
> isn't clear to me.
>
Sure. The granularity of the bitmap provides us with virtual bit groups.
for a granularity of say g=2, we have 2^2 virtual bits per every real bit:
101 in memory is treated, virtually, as 1111 0000 1111.
The get/set calls operate on virtual bits, not concrete ones, so if we
were to reset virtual bits 2-11:
11|11 0000 1111
We'd set the real bits to '000', because we clear or set the entire
virtual group.
This is probably not what we really want, so as a shortcut I just read
and then re-set the final bit.
It is programmatically avoidable (Are we truncating into a granularity
group?) but in the case that we are, I'd need to read/reset the bit
anyway, so it seemed fine to just unconditionally apply the fix.
^ permalink raw reply [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 15/20] block: Resize bitmaps on bdrv_truncate
2015-04-02 15:57 ` John Snow
@ 2015-04-07 12:57 ` Stefan Hajnoczi
2015-04-07 16:45 ` John Snow
0 siblings, 1 reply; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-07 12:57 UTC (permalink / raw)
To: John Snow
Cc: famz, qemu-block, Stefan Hajnoczi, qemu-devel, armbru,
vsementsov, mreitz
[-- Attachment #1: Type: text/plain, Size: 2980 bytes --]
On Thu, Apr 02, 2015 at 11:57:59AM -0400, John Snow wrote:
>
>
> On 04/02/2015 09:37 AM, Stefan Hajnoczi wrote:
> >On Fri, Mar 20, 2015 at 03:16:58PM -0400, John Snow wrote:
> >>+void hbitmap_truncate(HBitmap *hb, uint64_t size)
> >>+{
> >>+ bool shrink;
> >>+ unsigned i;
> >>+ uint64_t num_elements = size;
> >>+ uint64_t old;
> >>+
> >>+ /* Size comes in as logical elements, adjust for granularity. */
> >>+ size = (size + (1ULL << hb->granularity) - 1) >> hb->granularity;
> >>+ assert(size <= ((uint64_t)1 << HBITMAP_LOG_MAX_SIZE));
> >>+ shrink = size < hb->size;
> >>+
> >>+ /* bit sizes are identical; nothing to do. */
> >>+ if (size == hb->size) {
> >>+ return;
> >>+ }
> >>+
> >>+ /* If we're losing bits, let's clear those bits before we invalidate all of
> >>+ * our invariants. This helps keep the bitcount consistent, and will prevent
> >>+ * us from carrying around garbage bits beyond the end of the map.
> >>+ *
> >>+ * Because clearing bits past the end of map might reset bits we care about
> >>+ * within the array, record the current value of the last bit we're keeping.
> >>+ */
> >>+ if (shrink) {
> >>+ bool set = hbitmap_get(hb, num_elements - 1);
> >>+ uint64_t fix_count = (hb->size << hb->granularity) - num_elements;
> >>+
> >>+ assert(fix_count);
> >>+ hbitmap_reset(hb, num_elements, fix_count);
> >>+ if (set) {
> >>+ hbitmap_set(hb, num_elements - 1, 1);
> >>+ }
> >
> >Why is it necessary to set the last bit (if it was set)? The comment
> >isn't clear to me.
> >
>
> Sure. The granularity of the bitmap provides us with virtual bit groups. for
> a granularity of say g=2, we have 2^2 virtual bits per every real bit:
>
> 101 in memory is treated, virtually, as 1111 0000 1111.
>
> The get/set calls operate on virtual bits, not concrete ones, so if we were
> to reset virtual bits 2-11:
> 11|11 0000 1111
>
> We'd set the real bits to '000', because we clear or set the entire virtual
> group.
>
> This is probably not what we really want, so as a shortcut I just read and
> then re-set the final bit.
>
> It is programmatically avoidable (Are we truncating into a granularity
> group?) but in the case that we are, I'd need to read/reset the bit anyway,
> so it seemed fine to just unconditionally apply the fix.
I see. This is equivalent to:
uint64_t start = QEMU_ALIGN_UP(num_elements, hb->granularity);
uint64_t fix_count = (hb->size << hb->granularity) - start;
hbitmap_reset(hb, start, fix_count);
The explicit QEMU_ALIGN_UP(num_elements, hb->granularity) calculation
shows that we're working around the granularity. I find this easier to
understand.
If you keep the get/set version, please extend the comment to explain
that clearing the first bit could destroy up to granularity - 1 bits
that must be preserved.
Stefan
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^ permalink raw reply [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 15/20] block: Resize bitmaps on bdrv_truncate
2015-04-07 12:57 ` Stefan Hajnoczi
@ 2015-04-07 16:45 ` John Snow
2015-04-08 8:44 ` Stefan Hajnoczi
0 siblings, 1 reply; 54+ messages in thread
From: John Snow @ 2015-04-07 16:45 UTC (permalink / raw)
To: Stefan Hajnoczi
Cc: famz, qemu-block, Stefan Hajnoczi, qemu-devel, armbru,
vsementsov, mreitz
On 04/07/2015 08:57 AM, Stefan Hajnoczi wrote:
> On Thu, Apr 02, 2015 at 11:57:59AM -0400, John Snow wrote:
>>
>>
>> On 04/02/2015 09:37 AM, Stefan Hajnoczi wrote:
>>> On Fri, Mar 20, 2015 at 03:16:58PM -0400, John Snow wrote:
>>>> +void hbitmap_truncate(HBitmap *hb, uint64_t size)
>>>> +{
>>>> + bool shrink;
>>>> + unsigned i;
>>>> + uint64_t num_elements = size;
>>>> + uint64_t old;
>>>> +
>>>> + /* Size comes in as logical elements, adjust for granularity. */
>>>> + size = (size + (1ULL << hb->granularity) - 1) >> hb->granularity;
>>>> + assert(size <= ((uint64_t)1 << HBITMAP_LOG_MAX_SIZE));
>>>> + shrink = size < hb->size;
>>>> +
>>>> + /* bit sizes are identical; nothing to do. */
>>>> + if (size == hb->size) {
>>>> + return;
>>>> + }
>>>> +
>>>> + /* If we're losing bits, let's clear those bits before we invalidate all of
>>>> + * our invariants. This helps keep the bitcount consistent, and will prevent
>>>> + * us from carrying around garbage bits beyond the end of the map.
>>>> + *
>>>> + * Because clearing bits past the end of map might reset bits we care about
>>>> + * within the array, record the current value of the last bit we're keeping.
>>>> + */
>>>> + if (shrink) {
>>>> + bool set = hbitmap_get(hb, num_elements - 1);
>>>> + uint64_t fix_count = (hb->size << hb->granularity) - num_elements;
>>>> +
>>>> + assert(fix_count);
>>>> + hbitmap_reset(hb, num_elements, fix_count);
>>>> + if (set) {
>>>> + hbitmap_set(hb, num_elements - 1, 1);
>>>> + }
>>>
>>> Why is it necessary to set the last bit (if it was set)? The comment
>>> isn't clear to me.
>>>
>>
>> Sure. The granularity of the bitmap provides us with virtual bit groups. for
>> a granularity of say g=2, we have 2^2 virtual bits per every real bit:
>>
>> 101 in memory is treated, virtually, as 1111 0000 1111.
>>
>> The get/set calls operate on virtual bits, not concrete ones, so if we were
>> to reset virtual bits 2-11:
>> 11|11 0000 1111
>>
>> We'd set the real bits to '000', because we clear or set the entire virtual
>> group.
>>
>> This is probably not what we really want, so as a shortcut I just read and
>> then re-set the final bit.
>>
>> It is programmatically avoidable (Are we truncating into a granularity
>> group?) but in the case that we are, I'd need to read/reset the bit anyway,
>> so it seemed fine to just unconditionally apply the fix.
>
> I see. This is equivalent to:
>
> uint64_t start = QEMU_ALIGN_UP(num_elements, hb->granularity);
Probably you mean QEMU_ALIGN_UP(num_elements, 1 << hb->granularity)
> uint64_t fix_count = (hb->size << hb->granularity) - start;
> hbitmap_reset(hb, start, fix_count);
>
> The explicit QEMU_ALIGN_UP(num_elements, hb->granularity) calculation
> shows that we're working around the granularity. I find this easier to
> understand.
>
> If you keep the get/set version, please extend the comment to explain
> that clearing the first bit could destroy up to granularity - 1 bits
> that must be preserved.
>
Your solution will read more nicely, so I'll just adopt that, thanks.
> Stefan
>
^ permalink raw reply [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 15/20] block: Resize bitmaps on bdrv_truncate
2015-04-07 16:45 ` John Snow
@ 2015-04-08 8:44 ` Stefan Hajnoczi
0 siblings, 0 replies; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-08 8:44 UTC (permalink / raw)
To: John Snow
Cc: famz, qemu-block, Stefan Hajnoczi, qemu-devel, armbru,
vsementsov, mreitz
[-- Attachment #1: Type: text/plain, Size: 2905 bytes --]
On Tue, Apr 07, 2015 at 12:45:30PM -0400, John Snow wrote:
>
>
> On 04/07/2015 08:57 AM, Stefan Hajnoczi wrote:
> >On Thu, Apr 02, 2015 at 11:57:59AM -0400, John Snow wrote:
> >>
> >>
> >>On 04/02/2015 09:37 AM, Stefan Hajnoczi wrote:
> >>>On Fri, Mar 20, 2015 at 03:16:58PM -0400, John Snow wrote:
> >>>>+void hbitmap_truncate(HBitmap *hb, uint64_t size)
> >>>>+{
> >>>>+ bool shrink;
> >>>>+ unsigned i;
> >>>>+ uint64_t num_elements = size;
> >>>>+ uint64_t old;
> >>>>+
> >>>>+ /* Size comes in as logical elements, adjust for granularity. */
> >>>>+ size = (size + (1ULL << hb->granularity) - 1) >> hb->granularity;
> >>>>+ assert(size <= ((uint64_t)1 << HBITMAP_LOG_MAX_SIZE));
> >>>>+ shrink = size < hb->size;
> >>>>+
> >>>>+ /* bit sizes are identical; nothing to do. */
> >>>>+ if (size == hb->size) {
> >>>>+ return;
> >>>>+ }
> >>>>+
> >>>>+ /* If we're losing bits, let's clear those bits before we invalidate all of
> >>>>+ * our invariants. This helps keep the bitcount consistent, and will prevent
> >>>>+ * us from carrying around garbage bits beyond the end of the map.
> >>>>+ *
> >>>>+ * Because clearing bits past the end of map might reset bits we care about
> >>>>+ * within the array, record the current value of the last bit we're keeping.
> >>>>+ */
> >>>>+ if (shrink) {
> >>>>+ bool set = hbitmap_get(hb, num_elements - 1);
> >>>>+ uint64_t fix_count = (hb->size << hb->granularity) - num_elements;
> >>>>+
> >>>>+ assert(fix_count);
> >>>>+ hbitmap_reset(hb, num_elements, fix_count);
> >>>>+ if (set) {
> >>>>+ hbitmap_set(hb, num_elements - 1, 1);
> >>>>+ }
> >>>
> >>>Why is it necessary to set the last bit (if it was set)? The comment
> >>>isn't clear to me.
> >>>
> >>
> >>Sure. The granularity of the bitmap provides us with virtual bit groups. for
> >>a granularity of say g=2, we have 2^2 virtual bits per every real bit:
> >>
> >>101 in memory is treated, virtually, as 1111 0000 1111.
> >>
> >>The get/set calls operate on virtual bits, not concrete ones, so if we were
> >>to reset virtual bits 2-11:
> >>11|11 0000 1111
> >>
> >>We'd set the real bits to '000', because we clear or set the entire virtual
> >>group.
> >>
> >>This is probably not what we really want, so as a shortcut I just read and
> >>then re-set the final bit.
> >>
> >>It is programmatically avoidable (Are we truncating into a granularity
> >>group?) but in the case that we are, I'd need to read/reset the bit anyway,
> >>so it seemed fine to just unconditionally apply the fix.
> >
> >I see. This is equivalent to:
> >
> >uint64_t start = QEMU_ALIGN_UP(num_elements, hb->granularity);
>
> Probably you mean QEMU_ALIGN_UP(num_elements, 1 << hb->granularity)
Yes, you are right.
Stefan
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread
* [Qemu-devel] [PATCH v4 16/20] hbitmap: truncate tests
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (14 preceding siblings ...)
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 15/20] block: Resize bitmaps on bdrv_truncate John Snow
@ 2015-03-20 19:16 ` John Snow
2015-03-20 19:43 ` Max Reitz
2015-04-02 13:43 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2015-03-20 19:17 ` [Qemu-devel] [PATCH v4 17/20] iotests: add invalid input incremental backup tests John Snow
` (5 subsequent siblings)
21 siblings, 2 replies; 54+ messages in thread
From: John Snow @ 2015-03-20 19:16 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
The general approach is to set bits close to the boundaries of
where we are truncating and ensure that everything appears to
have gone OK.
We test growing and shrinking by different amounts:
- Less than the granularity
- Less than the granularity, but across a boundary
- Less than sizeof(unsigned long)
- Less than sizeof(unsigned long), but across a ulong boundary
- More than sizeof(unsigned long)
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
tests/test-hbitmap.c | 255 +++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 255 insertions(+)
diff --git a/tests/test-hbitmap.c b/tests/test-hbitmap.c
index 8c902f2..9f41b5f 100644
--- a/tests/test-hbitmap.c
+++ b/tests/test-hbitmap.c
@@ -11,6 +11,8 @@
#include <glib.h>
#include <stdarg.h>
+#include <string.h>
+#include <sys/types.h>
#include "qemu/hbitmap.h"
#define LOG_BITS_PER_LONG (BITS_PER_LONG == 32 ? 5 : 6)
@@ -23,6 +25,7 @@ typedef struct TestHBitmapData {
HBitmap *hb;
unsigned long *bits;
size_t size;
+ size_t old_size;
int granularity;
} TestHBitmapData;
@@ -91,6 +94,44 @@ static void hbitmap_test_init(TestHBitmapData *data,
}
}
+static inline size_t hbitmap_test_array_size(size_t bits)
+{
+ size_t n = (bits + BITS_PER_LONG - 1) / BITS_PER_LONG;
+ return n ? n : 1;
+}
+
+static void hbitmap_test_truncate_impl(TestHBitmapData *data,
+ size_t size)
+{
+ size_t n;
+ size_t m;
+ data->old_size = data->size;
+ data->size = size;
+
+ if (data->size == data->old_size) {
+ return;
+ }
+
+ n = hbitmap_test_array_size(size);
+ m = hbitmap_test_array_size(data->old_size);
+ data->bits = g_realloc(data->bits, sizeof(unsigned long) * n);
+ if (n > m) {
+ memset(&data->bits[m], 0x00, sizeof(unsigned long) * (n - m));
+ }
+
+ /* If we shrink to an uneven multiple of sizeof(unsigned long),
+ * scrub the leftover memory. */
+ if (data->size < data->old_size) {
+ m = size % (sizeof(unsigned long) * 8);
+ if (m) {
+ unsigned long mask = (1ULL << m) - 1;
+ data->bits[n-1] &= mask;
+ }
+ }
+
+ hbitmap_truncate(data->hb, size);
+}
+
static void hbitmap_test_teardown(TestHBitmapData *data,
const void *unused)
{
@@ -369,6 +410,198 @@ static void test_hbitmap_iter_granularity(TestHBitmapData *data,
g_assert_cmpint(hbitmap_iter_next(&hbi), <, 0);
}
+static void hbitmap_test_set_boundary_bits(TestHBitmapData *data, ssize_t diff)
+{
+ size_t size = data->size;
+
+ /* First bit */
+ hbitmap_test_set(data, 0, 1);
+ if (diff < 0) {
+ /* Last bit in new, shortened map */
+ hbitmap_test_set(data, size + diff - 1, 1);
+
+ /* First bit to be truncated away */
+ hbitmap_test_set(data, size + diff, 1);
+ }
+ /* Last bit */
+ hbitmap_test_set(data, size - 1, 1);
+ if (data->granularity == 0) {
+ hbitmap_test_check_get(data);
+ }
+}
+
+static void hbitmap_test_check_boundary_bits(TestHBitmapData *data)
+{
+ size_t size = MIN(data->size, data->old_size);
+
+ if (data->granularity == 0) {
+ hbitmap_test_check_get(data);
+ hbitmap_test_check(data, 0);
+ } else {
+ /* If a granularity was set, note that every distinct
+ * (bit >> granularity) value that was set will increase
+ * the bit pop count by 2^granularity, not just 1.
+ *
+ * The hbitmap_test_check facility does not currently tolerate
+ * non-zero granularities, so test the boundaries and the population
+ * count manually.
+ */
+ g_assert(hbitmap_get(data->hb, 0));
+ g_assert(hbitmap_get(data->hb, size - 1));
+ g_assert_cmpint(2 << data->granularity, ==, hbitmap_count(data->hb));
+ }
+}
+
+/* Generic truncate test. */
+static void hbitmap_test_truncate(TestHBitmapData *data,
+ size_t size,
+ ssize_t diff,
+ int granularity)
+{
+ hbitmap_test_init(data, size, granularity);
+ hbitmap_test_set_boundary_bits(data, diff);
+ hbitmap_test_truncate_impl(data, size + diff);
+ hbitmap_test_check_boundary_bits(data);
+}
+
+static void test_hbitmap_truncate_nop(TestHBitmapData *data,
+ const void *unused)
+{
+ hbitmap_test_truncate(data, L2, 0, 0);
+}
+
+/**
+ * Grow by an amount smaller than the granularity, without crossing
+ * a granularity alignment boundary. Effectively a NOP.
+ */
+static void test_hbitmap_truncate_grow_negligible(TestHBitmapData *data,
+ const void *unused)
+{
+ size_t size = L2 - 1;
+ size_t diff = 1;
+ int granularity = 1;
+
+ hbitmap_test_truncate(data, size, diff, granularity);
+}
+
+/**
+ * Shrink by an amount smaller than the granularity, without crossing
+ * a granularity alignment boundary. Effectively a NOP.
+ */
+static void test_hbitmap_truncate_shrink_negligible(TestHBitmapData *data,
+ const void *unused)
+{
+ size_t size = L2;
+ ssize_t diff = -1;
+ int granularity = 1;
+
+ hbitmap_test_truncate(data, size, diff, granularity);
+}
+
+/**
+ * Grow by an amount smaller than the granularity, but crossing over
+ * a granularity alignment boundary.
+ */
+static void test_hbitmap_truncate_grow_tiny(TestHBitmapData *data,
+ const void *unused)
+{
+ size_t size = L2 - 2;
+ ssize_t diff = 1;
+ int granularity = 1;
+
+ hbitmap_test_truncate(data, size, diff, granularity);
+}
+
+/**
+ * Shrink by an amount smaller than the granularity, but crossing over
+ * a granularity alignment boundary.
+ */
+static void test_hbitmap_truncate_shrink_tiny(TestHBitmapData *data,
+ const void *unused)
+{
+ size_t size = L2 - 1;
+ ssize_t diff = -1;
+ int granularity = 1;
+
+ hbitmap_test_truncate(data, size, diff, granularity);
+}
+
+/**
+ * Grow by an amount smaller than sizeof(long), and not crossing over
+ * a sizeof(long) alignment boundary.
+ */
+static void test_hbitmap_truncate_grow_small(TestHBitmapData *data,
+ const void *unused)
+{
+ size_t size = L2 + 1;
+ size_t diff = sizeof(long) / 2;
+
+ hbitmap_test_truncate(data, size, diff, 0);
+}
+
+/**
+ * Shrink by an amount smaller than sizeof(long), and not crossing over
+ * a sizeof(long) alignment boundary.
+ */
+static void test_hbitmap_truncate_shrink_small(TestHBitmapData *data,
+ const void *unused)
+{
+ size_t size = L2;
+ size_t diff = sizeof(long) / 2;
+
+ hbitmap_test_truncate(data, size, -diff, 0);
+}
+
+/**
+ * Grow by an amount smaller than sizeof(long), while crossing over
+ * a sizeof(long) alignment boundary.
+ */
+static void test_hbitmap_truncate_grow_medium(TestHBitmapData *data,
+ const void *unused)
+{
+ size_t size = L2 - 1;
+ size_t diff = sizeof(long) / 2;
+
+ hbitmap_test_truncate(data, size, diff, 0);
+}
+
+/**
+ * Shrink by an amount smaller than sizeof(long), while crossing over
+ * a sizeof(long) alignment boundary.
+ */
+static void test_hbitmap_truncate_shrink_medium(TestHBitmapData *data,
+ const void *unused)
+{
+ size_t size = L2 + 1;
+ size_t diff = sizeof(long) / 2;
+
+ hbitmap_test_truncate(data, size, -diff, 0);
+}
+
+/**
+ * Grow by an amount larger than sizeof(long).
+ */
+static void test_hbitmap_truncate_grow_large(TestHBitmapData *data,
+ const void *unused)
+{
+ size_t size = L2;
+ size_t diff = 8 * sizeof(long);
+
+ hbitmap_test_truncate(data, size, diff, 0);
+}
+
+/**
+ * Shrink by an amount larger than sizeof(long).
+ */
+static void test_hbitmap_truncate_shrink_large(TestHBitmapData *data,
+ const void *unused)
+{
+ size_t size = L2;
+ size_t diff = 8 * sizeof(long);
+
+ hbitmap_test_truncate(data, size, -diff, 0);
+}
+
static void hbitmap_test_add(const char *testpath,
void (*test_func)(TestHBitmapData *data, const void *user_data))
{
@@ -395,6 +628,28 @@ int main(int argc, char **argv)
hbitmap_test_add("/hbitmap/reset/empty", test_hbitmap_reset_empty);
hbitmap_test_add("/hbitmap/reset/general", test_hbitmap_reset);
hbitmap_test_add("/hbitmap/granularity", test_hbitmap_granularity);
+
+ hbitmap_test_add("/hbitmap/truncate/nop", test_hbitmap_truncate_nop);
+ hbitmap_test_add("/hbitmap/truncate/grow/negligible",
+ test_hbitmap_truncate_grow_negligible);
+ hbitmap_test_add("/hbitmap/truncate/shrink/negligible",
+ test_hbitmap_truncate_shrink_negligible);
+ hbitmap_test_add("/hbitmap/truncate/grow/tiny",
+ test_hbitmap_truncate_grow_tiny);
+ hbitmap_test_add("/hbitmap/truncate/shrink/tiny",
+ test_hbitmap_truncate_shrink_tiny);
+ hbitmap_test_add("/hbitmap/truncate/grow/small",
+ test_hbitmap_truncate_grow_small);
+ hbitmap_test_add("/hbitmap/truncate/shrink/small",
+ test_hbitmap_truncate_shrink_small);
+ hbitmap_test_add("/hbitmap/truncate/grow/medium",
+ test_hbitmap_truncate_grow_medium);
+ hbitmap_test_add("/hbitmap/truncate/shrink/medium",
+ test_hbitmap_truncate_shrink_medium);
+ hbitmap_test_add("/hbitmap/truncate/grow/large",
+ test_hbitmap_truncate_grow_large);
+ hbitmap_test_add("/hbitmap/truncate/shrink/large",
+ test_hbitmap_truncate_shrink_large);
g_test_run();
return 0;
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [PATCH v4 16/20] hbitmap: truncate tests
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 16/20] hbitmap: truncate tests John Snow
@ 2015-03-20 19:43 ` Max Reitz
2015-04-02 13:43 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
1 sibling, 0 replies; 54+ messages in thread
From: Max Reitz @ 2015-03-20 19:43 UTC (permalink / raw)
To: John Snow, qemu-block
Cc: kwolf, famz, qemu-devel, armbru, vsementsov, stefanha
On 2015-03-20 at 15:16, John Snow wrote:
> The general approach is to set bits close to the boundaries of
> where we are truncating and ensure that everything appears to
> have gone OK.
>
> We test growing and shrinking by different amounts:
> - Less than the granularity
> - Less than the granularity, but across a boundary
> - Less than sizeof(unsigned long)
> - Less than sizeof(unsigned long), but across a ulong boundary
> - More than sizeof(unsigned long)
>
> Signed-off-by: John Snow <jsnow@redhat.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
> ---
> tests/test-hbitmap.c | 255 +++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 255 insertions(+)
>
> diff --git a/tests/test-hbitmap.c b/tests/test-hbitmap.c
> index 8c902f2..9f41b5f 100644
> --- a/tests/test-hbitmap.c
> +++ b/tests/test-hbitmap.c
[snip]
> +
> +static void hbitmap_test_check_boundary_bits(TestHBitmapData *data)
> +{
> + size_t size = MIN(data->size, data->old_size);
> +
> + if (data->granularity == 0) {
> + hbitmap_test_check_get(data);
> + hbitmap_test_check(data, 0);
> + } else {
> + /* If a granularity was set, note that every distinct
> + * (bit >> granularity) value that was set will increase
> + * the bit pop count by 2^granularity, not just 1.
> + *
> + * The hbitmap_test_check facility does not currently tolerate
> + * non-zero granularities, so test the boundaries and the population
> + * count manually.
> + */
Thanks!
Max
^ permalink raw reply [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 16/20] hbitmap: truncate tests
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 16/20] hbitmap: truncate tests John Snow
2015-03-20 19:43 ` Max Reitz
@ 2015-04-02 13:43 ` Stefan Hajnoczi
1 sibling, 0 replies; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-02 13:43 UTC (permalink / raw)
To: John Snow
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
[-- Attachment #1: Type: text/plain, Size: 771 bytes --]
On Fri, Mar 20, 2015 at 03:16:59PM -0400, John Snow wrote:
> The general approach is to set bits close to the boundaries of
> where we are truncating and ensure that everything appears to
> have gone OK.
>
> We test growing and shrinking by different amounts:
> - Less than the granularity
> - Less than the granularity, but across a boundary
> - Less than sizeof(unsigned long)
> - Less than sizeof(unsigned long), but across a ulong boundary
> - More than sizeof(unsigned long)
>
> Signed-off-by: John Snow <jsnow@redhat.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
> ---
> tests/test-hbitmap.c | 255 +++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 255 insertions(+)
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread
* [Qemu-devel] [PATCH v4 17/20] iotests: add invalid input incremental backup tests
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (15 preceding siblings ...)
2015-03-20 19:16 ` [Qemu-devel] [PATCH v4 16/20] hbitmap: truncate tests John Snow
@ 2015-03-20 19:17 ` John Snow
2015-03-20 19:49 ` Max Reitz
2015-04-02 13:44 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2015-03-20 19:17 ` [Qemu-devel] [PATCH v4 18/20] iotests: add QMP event waiting queue John Snow
` (4 subsequent siblings)
21 siblings, 2 replies; 54+ messages in thread
From: John Snow @ 2015-03-20 19:17 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
Signed-off-by: John Snow <jsnow@redhat.com>
---
tests/qemu-iotests/124 | 104 +++++++++++++++++++++++++++++++++++++++++++++
tests/qemu-iotests/124.out | 5 +++
tests/qemu-iotests/group | 1 +
3 files changed, 110 insertions(+)
create mode 100644 tests/qemu-iotests/124
create mode 100644 tests/qemu-iotests/124.out
diff --git a/tests/qemu-iotests/124 b/tests/qemu-iotests/124
new file mode 100644
index 0000000..85675ec
--- /dev/null
+++ b/tests/qemu-iotests/124
@@ -0,0 +1,104 @@
+#!/usr/bin/env python
+#
+# Tests for incremental drive-backup
+#
+# Copyright (C) 2015 John Snow for Red Hat, Inc.
+#
+# Based on 056.
+#
+# 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 os
+import iotests
+
+
+def io_write_patterns(img, patterns):
+ for pattern in patterns:
+ iotests.qemu_io('-c', 'write -P%s %s %s' % pattern, img)
+
+
+class TestIncrementalBackup(iotests.QMPTestCase):
+ def setUp(self):
+ self.bitmaps = list()
+ self.files = list()
+ self.drives = list()
+ self.vm = iotests.VM()
+ self.err_img = os.path.join(iotests.test_dir, 'err.%s' % iotests.imgfmt)
+
+ # Create a base image with a distinctive patterning
+ drive0 = self.add_node('drive0')
+ self.img_create(drive0['file'], drive0['fmt'])
+ self.vm.add_drive(drive0['file'])
+ io_write_patterns(drive0['file'], (('0x41', 0, 512),
+ ('0xd5', '1M', '32k'),
+ ('0xdc', '32M', '124k')))
+ self.vm.launch()
+
+
+ def add_node(self, node_id, fmt=iotests.imgfmt, path=None, backup=None):
+ if path is None:
+ path = os.path.join(iotests.test_dir, '%s.%s' % (node_id, fmt))
+ if backup is None:
+ backup = os.path.join(iotests.test_dir,
+ '%s.full.backup.%s' % (node_id, fmt))
+
+ self.drives.append({
+ 'id': node_id,
+ 'file': path,
+ 'backup': backup,
+ 'fmt': fmt })
+ return self.drives[-1]
+
+
+ def img_create(self, img, fmt=iotests.imgfmt, size='64M',
+ parent=None, parentFormat=None):
+ if parent:
+ if parentFormat is None:
+ parentFormat = fmt
+ iotests.qemu_img('create', '-f', fmt, img, size,
+ '-b', parent, '-F', parentFormat)
+ else:
+ iotests.qemu_img('create', '-f', fmt, img, size)
+ self.files.append(img)
+
+ def test_sync_dirty_bitmap_missing(self):
+ self.assert_no_active_block_jobs()
+ self.files.append(self.err_img)
+ result = self.vm.qmp('drive-backup', device=self.drives[0]['id'],
+ sync='dirty-bitmap', format=self.drives[0]['fmt'],
+ target=self.err_img)
+ self.assert_qmp(result, 'error/class', 'GenericError')
+
+
+ def test_sync_dirty_bitmap_not_found(self):
+ self.assert_no_active_block_jobs()
+ self.files.append(self.err_img)
+ result = self.vm.qmp('drive-backup', device=self.drives[0]['id'],
+ sync='dirty-bitmap', bitmap='unknown',
+ format=self.drives[0]['fmt'], target=self.err_img)
+ self.assert_qmp(result, 'error/class', 'GenericError')
+
+
+ def tearDown(self):
+ self.vm.shutdown()
+ for filename in self.files:
+ try:
+ os.remove(filename)
+ except OSError:
+ pass
+
+
+if __name__ == '__main__':
+ iotests.main(supported_fmts=['qcow2'])
diff --git a/tests/qemu-iotests/124.out b/tests/qemu-iotests/124.out
new file mode 100644
index 0000000..fbc63e6
--- /dev/null
+++ b/tests/qemu-iotests/124.out
@@ -0,0 +1,5 @@
+..
+----------------------------------------------------------------------
+Ran 2 tests
+
+OK
diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
index 6262127..020f357 100644
--- a/tests/qemu-iotests/group
+++ b/tests/qemu-iotests/group
@@ -123,4 +123,5 @@
116 rw auto quick
121 rw auto
123 rw auto quick
+124 rw auto backing
128 rw auto quick
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [PATCH v4 17/20] iotests: add invalid input incremental backup tests
2015-03-20 19:17 ` [Qemu-devel] [PATCH v4 17/20] iotests: add invalid input incremental backup tests John Snow
@ 2015-03-20 19:49 ` Max Reitz
2015-04-02 13:44 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
1 sibling, 0 replies; 54+ messages in thread
From: Max Reitz @ 2015-03-20 19:49 UTC (permalink / raw)
To: John Snow, qemu-block
Cc: kwolf, famz, qemu-devel, armbru, vsementsov, stefanha
On 2015-03-20 at 15:17, John Snow wrote:
> Signed-off-by: John Snow <jsnow@redhat.com>
> ---
> tests/qemu-iotests/124 | 104 +++++++++++++++++++++++++++++++++++++++++++++
> tests/qemu-iotests/124.out | 5 +++
> tests/qemu-iotests/group | 1 +
> 3 files changed, 110 insertions(+)
> create mode 100644 tests/qemu-iotests/124
> create mode 100644 tests/qemu-iotests/124.out
Reviewed-by: Max Reitz <mreitz@redhat.com>
^ permalink raw reply [flat|nested] 54+ messages in thread
* Re: [Qemu-devel] [Qemu-block] [PATCH v4 17/20] iotests: add invalid input incremental backup tests
2015-03-20 19:17 ` [Qemu-devel] [PATCH v4 17/20] iotests: add invalid input incremental backup tests John Snow
2015-03-20 19:49 ` Max Reitz
@ 2015-04-02 13:44 ` Stefan Hajnoczi
1 sibling, 0 replies; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-02 13:44 UTC (permalink / raw)
To: John Snow
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
[-- Attachment #1: Type: text/plain, Size: 455 bytes --]
On Fri, Mar 20, 2015 at 03:17:00PM -0400, John Snow wrote:
> Signed-off-by: John Snow <jsnow@redhat.com>
> ---
> tests/qemu-iotests/124 | 104 +++++++++++++++++++++++++++++++++++++++++++++
> tests/qemu-iotests/124.out | 5 +++
> tests/qemu-iotests/group | 1 +
> 3 files changed, 110 insertions(+)
> create mode 100644 tests/qemu-iotests/124
> create mode 100644 tests/qemu-iotests/124.out
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread
* [Qemu-devel] [PATCH v4 18/20] iotests: add QMP event waiting queue
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (16 preceding siblings ...)
2015-03-20 19:17 ` [Qemu-devel] [PATCH v4 17/20] iotests: add invalid input incremental backup tests John Snow
@ 2015-03-20 19:17 ` John Snow
2015-04-02 13:57 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2015-03-20 19:17 ` [Qemu-devel] [PATCH v4 19/20] iotests: add simple incremental backup case John Snow
` (3 subsequent siblings)
21 siblings, 1 reply; 54+ messages in thread
From: John Snow @ 2015-03-20 19:17 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
A filter is added to allow callers to request very specific
events to be pulled from the event queue, while leaving undesired
events still in the stream.
This allows to poll for completion data for multiple asynchronous
events in any arbitrary order.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
tests/qemu-iotests/iotests.py | 38 ++++++++++++++++++++++++++++++++++++++
1 file changed, 38 insertions(+)
diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index 1402854..ac55813 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -78,6 +78,23 @@ def create_image(name, size):
i = i + 512
file.close()
+# Test if 'match' is a recursive subset of 'event'
+def event_match(event, match = None):
+ if match is None:
+ return True
+
+ for key in match:
+ if key in event:
+ if isinstance(event[key], dict):
+ if not event_match(event[key], match[key]):
+ return False
+ elif event[key] != match[key]:
+ return False
+ else:
+ return False
+
+ return True
+
class VM(object):
'''A QEMU VM'''
@@ -92,6 +109,7 @@ class VM(object):
'-machine', 'accel=qtest',
'-display', 'none', '-vga', 'none']
self._num_drives = 0
+ self._events = []
# This can be used to add an unused monitor instance.
def add_monitor_telnet(self, ip, port):
@@ -202,14 +220,34 @@ class VM(object):
def get_qmp_event(self, wait=False):
'''Poll for one queued QMP events and return it'''
+ if len(self._events) > 0:
+ return self._events.pop(0)
return self._qmp.pull_event(wait=wait)
def get_qmp_events(self, wait=False):
'''Poll for queued QMP events and return a list of dicts'''
events = self._qmp.get_events(wait=wait)
+ events.extend(self._events)
+ del self._events[:]
self._qmp.clear_events()
return events
+ def event_wait(self, name='BLOCK_JOB_COMPLETED', maxtries=3, match=None):
+ # Search cached events
+ for event in self._events:
+ if (event['event'] == name) and event_match(event, match):
+ self._events.remove(event)
+ return event
+
+ # Poll for new events
+ for _ in range(maxtries):
+ event = self._qmp.pull_event(wait=True)
+ if (event['event'] == name) and event_match(event, match):
+ return event
+ self._events.append(event)
+
+ return None
+
index_re = re.compile(r'([^\[]+)\[([^\]]+)\]')
class QMPTestCase(unittest.TestCase):
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 18/20] iotests: add QMP event waiting queue
2015-03-20 19:17 ` [Qemu-devel] [PATCH v4 18/20] iotests: add QMP event waiting queue John Snow
@ 2015-04-02 13:57 ` Stefan Hajnoczi
2015-04-02 17:19 ` John Snow
0 siblings, 1 reply; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-02 13:57 UTC (permalink / raw)
To: John Snow
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
[-- Attachment #1: Type: text/plain, Size: 1254 bytes --]
On Fri, Mar 20, 2015 at 03:17:01PM -0400, John Snow wrote:
> +# Test if 'match' is a recursive subset of 'event'
> +def event_match(event, match = None):
Not worth respinning but PEP8 says there should be no spaces around the
'=' for keyword arguments:
https://www.python.org/dev/peps/pep-0008/#whitespace-in-expressions-and-statements
> + def event_wait(self, name='BLOCK_JOB_COMPLETED', maxtries=3, match=None):
> + # Search cached events
> + for event in self._events:
> + if (event['event'] == name) and event_match(event, match):
> + self._events.remove(event)
> + return event
> +
> + # Poll for new events
> + for _ in range(maxtries):
> + event = self._qmp.pull_event(wait=True)
> + if (event['event'] == name) and event_match(event, match):
> + return event
> + self._events.append(event)
> +
> + return None
I'm not sure if maxtries is useful. Why is a particular number of
skipped events useful to the caller and how do they pick the magic
number?
If you added the argument because this is a blocking operation then we
should probably use timeouts instead. Timeouts will bail out even if
QEMU is unresponsive.
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread
* Re: [Qemu-devel] [Qemu-block] [PATCH v4 18/20] iotests: add QMP event waiting queue
2015-04-02 13:57 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
@ 2015-04-02 17:19 ` John Snow
0 siblings, 0 replies; 54+ messages in thread
From: John Snow @ 2015-04-02 17:19 UTC (permalink / raw)
To: Stefan Hajnoczi
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
On 04/02/2015 09:57 AM, Stefan Hajnoczi wrote:
> On Fri, Mar 20, 2015 at 03:17:01PM -0400, John Snow wrote:
>> +# Test if 'match' is a recursive subset of 'event'
>> +def event_match(event, match = None):
>
> Not worth respinning but PEP8 says there should be no spaces around the
> '=' for keyword arguments:
> https://www.python.org/dev/peps/pep-0008/#whitespace-in-expressions-and-statements
>
>> + def event_wait(self, name='BLOCK_JOB_COMPLETED', maxtries=3, match=None):
>> + # Search cached events
>> + for event in self._events:
>> + if (event['event'] == name) and event_match(event, match):
>> + self._events.remove(event)
>> + return event
>> +
>> + # Poll for new events
>> + for _ in range(maxtries):
>> + event = self._qmp.pull_event(wait=True)
>> + if (event['event'] == name) and event_match(event, match):
>> + return event
>> + self._events.append(event)
>> +
>> + return None
>
> I'm not sure if maxtries is useful. Why is a particular number of
> skipped events useful to the caller and how do they pick the magic
> number?
>
> If you added the argument because this is a blocking operation then we
> should probably use timeouts instead. Timeouts will bail out even if
> QEMU is unresponsive.
>
Yeah, this was just a poor man's timeout.
I'll make it nicer.
^ permalink raw reply [flat|nested] 54+ messages in thread
* [Qemu-devel] [PATCH v4 19/20] iotests: add simple incremental backup case
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (17 preceding siblings ...)
2015-03-20 19:17 ` [Qemu-devel] [PATCH v4 18/20] iotests: add QMP event waiting queue John Snow
@ 2015-03-20 19:17 ` John Snow
2015-03-20 19:50 ` Max Reitz
2015-04-02 14:27 ` Stefan Hajnoczi
2015-03-20 19:17 ` [Qemu-devel] [PATCH v4 20/20] iotests: add incremental backup failure recovery test John Snow
` (2 subsequent siblings)
21 siblings, 2 replies; 54+ messages in thread
From: John Snow @ 2015-03-20 19:17 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
Signed-off-by: John Snow <jsnow@redhat.com>
---
tests/qemu-iotests/124 | 153 +++++++++++++++++++++++++++++++++++++++++++++
tests/qemu-iotests/124.out | 4 +-
2 files changed, 155 insertions(+), 2 deletions(-)
diff --git a/tests/qemu-iotests/124 b/tests/qemu-iotests/124
index 85675ec..ce2cda7 100644
--- a/tests/qemu-iotests/124
+++ b/tests/qemu-iotests/124
@@ -28,6 +28,42 @@ def io_write_patterns(img, patterns):
for pattern in patterns:
iotests.qemu_io('-c', 'write -P%s %s %s' % pattern, img)
+class Bitmap:
+ def __init__(self, name, drive):
+ self.name = name
+ self.drive = drive
+ self.pattern = os.path.join(iotests.test_dir.replace('%', '%%'),
+ '%s.%s.backup.%%i.img' % (drive['id'],
+ name))
+ self.num = 0
+ self.backups = list()
+
+ def base_target(self):
+ return self.drive['backup']
+
+ def new_target(self, num=None):
+ if num is None:
+ num = self.num
+ self.num = num + 1
+ target = self.pattern % num
+ self.backups.append(target)
+ return target
+
+ def last_target(self):
+ if self.backups:
+ return self.backups[-1]
+ return self.base_target()
+
+ def del_target(self):
+ os.remove(self.backups.pop())
+ self.num -= 1
+
+ def __del__(self):
+ for backup in self.backups:
+ try:
+ os.remove(backup)
+ except OSError:
+ pass
class TestIncrementalBackup(iotests.QMPTestCase):
def setUp(self):
@@ -73,6 +109,123 @@ class TestIncrementalBackup(iotests.QMPTestCase):
iotests.qemu_img('create', '-f', fmt, img, size)
self.files.append(img)
+
+ def create_full_backup(self, drive=None):
+ if drive is None:
+ drive = self.drives[-1]
+
+ res = self.vm.qmp('drive-backup', device=drive['id'],
+ sync='full', format=drive['fmt'],
+ target=drive['backup'])
+ self.assert_qmp(res, 'return', {})
+ self.wait_until_completed(drive['id'])
+ self.check_full_backup(drive)
+ self.files.append(drive['backup'])
+ return drive['backup']
+
+
+ def check_full_backup(self, drive=None):
+ if drive is None:
+ drive = self.drives[-1]
+ self.assertTrue(iotests.compare_images(drive['file'], drive['backup']))
+
+
+ def add_bitmap(self, name, drive):
+ bitmap = Bitmap(name, drive)
+ self.bitmaps.append(bitmap)
+ result = self.vm.qmp('block-dirty-bitmap-add', node=drive['id'],
+ name=bitmap.name)
+ self.assert_qmp(result, 'return', {})
+ return bitmap
+
+
+ def prepare_backup(self, bitmap=None, parent=None):
+ if bitmap is None:
+ bitmap = self.bitmaps[-1]
+ if parent is None:
+ parent = bitmap.last_target()
+
+ target = bitmap.new_target()
+ self.img_create(target, bitmap.drive['fmt'], parent=parent)
+ return target
+
+
+ def create_incremental(self, bitmap=None, parent=None,
+ parentFormat=None, validate=True):
+ if bitmap is None:
+ bitmap = self.bitmaps[-1]
+ if parent is None:
+ parent = bitmap.last_target()
+
+ target = self.prepare_backup(bitmap, parent)
+ result = self.vm.qmp('drive-backup', device=bitmap.drive['id'],
+ sync='dirty-bitmap', bitmap=bitmap.name,
+ format=bitmap.drive['fmt'], target=target,
+ mode='existing')
+ self.assert_qmp(result, 'return', {})
+
+ return self.wait_incremental(bitmap, validate)
+
+
+ def wait_incremental(self, bitmap=None, validate=True,
+ error='Input/output error'):
+ if bitmap is None:
+ bitmap = self.bitmaps[-1]
+
+ event = self.vm.event_wait(name="BLOCK_JOB_COMPLETED",
+ match={'data': {'device':
+ bitmap.drive['id']}})
+ if validate:
+ self.assert_qmp_absent(event, 'data/error')
+ self.assert_qmp(event, 'data/offset', event['data']['len'])
+ return self.check_incremental(bitmap)
+ else:
+ self.assert_qmp(event, 'data/error', error)
+ bitmap.del_target()
+ return False
+
+
+ def check_incremental(self, bitmap=None):
+ if bitmap is None:
+ bitmap = self.bitmaps[-1]
+ self.assertTrue(iotests.compare_images(bitmap.drive['file'],
+ bitmap.last_target()))
+ return True
+
+
+ def hmp_io_writes(self, drive, patterns):
+ for pattern in patterns:
+ self.vm.hmp_qemu_io(drive, 'write -P%s %s %s' % pattern)
+ self.vm.hmp_qemu_io(drive, 'flush')
+
+
+ def test_incremental_simple(self):
+ '''
+ Test: Create and verify three incremental backups.
+
+ Create a bitmap and a full backup before VM execution begins,
+ then create a series of three incremental backups "during execution,"
+ i.e.; after IO requests begin modifying the drive.
+ '''
+ self.create_full_backup()
+ self.add_bitmap('bitmap0', self.drives[0])
+
+ # Sanity: Create a "hollow" incremental backup
+ self.create_incremental()
+ # Three writes: One complete overwrite, one new segment,
+ # and one partial overlap.
+ self.hmp_io_writes(self.drives[0]['id'], (('0xab', 0, 512),
+ ('0xfe', '16M', '256k'),
+ ('0x64', '32736k', '64k')))
+ self.create_incremental()
+ # Three more writes, one of each kind, like above
+ self.hmp_io_writes(self.drives[0]['id'], (('0x9a', 0, 512),
+ ('0x55', '8M', '352k'),
+ ('0x78', '15872k', '1M')))
+ self.create_incremental()
+ return True
+
+
def test_sync_dirty_bitmap_missing(self):
self.assert_no_active_block_jobs()
self.files.append(self.err_img)
diff --git a/tests/qemu-iotests/124.out b/tests/qemu-iotests/124.out
index fbc63e6..8d7e996 100644
--- a/tests/qemu-iotests/124.out
+++ b/tests/qemu-iotests/124.out
@@ -1,5 +1,5 @@
-..
+...
----------------------------------------------------------------------
-Ran 2 tests
+Ran 3 tests
OK
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [PATCH v4 19/20] iotests: add simple incremental backup case
2015-03-20 19:17 ` [Qemu-devel] [PATCH v4 19/20] iotests: add simple incremental backup case John Snow
@ 2015-03-20 19:50 ` Max Reitz
2015-04-02 14:27 ` Stefan Hajnoczi
1 sibling, 0 replies; 54+ messages in thread
From: Max Reitz @ 2015-03-20 19:50 UTC (permalink / raw)
To: John Snow, qemu-block
Cc: kwolf, famz, qemu-devel, armbru, vsementsov, stefanha
On 2015-03-20 at 15:17, John Snow wrote:
> Signed-off-by: John Snow <jsnow@redhat.com>
> ---
> tests/qemu-iotests/124 | 153 +++++++++++++++++++++++++++++++++++++++++++++
> tests/qemu-iotests/124.out | 4 +-
> 2 files changed, 155 insertions(+), 2 deletions(-)
Reviewed-by: Max Reitz <mreitz@redhat.com>
^ permalink raw reply [flat|nested] 54+ messages in thread
* Re: [Qemu-devel] [PATCH v4 19/20] iotests: add simple incremental backup case
2015-03-20 19:17 ` [Qemu-devel] [PATCH v4 19/20] iotests: add simple incremental backup case John Snow
2015-03-20 19:50 ` Max Reitz
@ 2015-04-02 14:27 ` Stefan Hajnoczi
2015-04-06 21:49 ` John Snow
1 sibling, 1 reply; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-02 14:27 UTC (permalink / raw)
To: John Snow
Cc: kwolf, famz, qemu-block, qemu-devel, armbru, vsementsov,
stefanha, mreitz
[-- Attachment #1: Type: text/plain, Size: 3913 bytes --]
On Fri, Mar 20, 2015 at 03:17:02PM -0400, John Snow wrote:
> Signed-off-by: John Snow <jsnow@redhat.com>
> ---
> tests/qemu-iotests/124 | 153 +++++++++++++++++++++++++++++++++++++++++++++
> tests/qemu-iotests/124.out | 4 +-
> 2 files changed, 155 insertions(+), 2 deletions(-)
>
> diff --git a/tests/qemu-iotests/124 b/tests/qemu-iotests/124
> index 85675ec..ce2cda7 100644
> --- a/tests/qemu-iotests/124
> +++ b/tests/qemu-iotests/124
> @@ -28,6 +28,42 @@ def io_write_patterns(img, patterns):
> for pattern in patterns:
> iotests.qemu_io('-c', 'write -P%s %s %s' % pattern, img)
>
> +class Bitmap:
> + def __init__(self, name, drive):
> + self.name = name
> + self.drive = drive
> + self.pattern = os.path.join(iotests.test_dir.replace('%', '%%'),
> + '%s.%s.backup.%%i.img' % (drive['id'],
> + name))
drive['id'] and name aren't escaped.
It is simpler and safer to format the string from scratch in
new_target() and drop the Bitmap.pattern field:
def new_target(self, num=None):
...
filename = '%s.%s.backup.%i.img' % (self.drive['id'],
self.name,
num)
target = os.path.join(iotests.test_dir, filename)
> + self.num = 0
> + self.backups = list()
> +
> + def base_target(self):
> + return self.drive['backup']
> +
> + def new_target(self, num=None):
> + if num is None:
> + num = self.num
> + self.num = num + 1
> + target = self.pattern % num
> + self.backups.append(target)
> + return target
> +
> + def last_target(self):
> + if self.backups:
> + return self.backups[-1]
> + return self.base_target()
> +
> + def del_target(self):
> + os.remove(self.backups.pop())
> + self.num -= 1
> +
> + def __del__(self):
> + for backup in self.backups:
> + try:
> + os.remove(backup)
> + except OSError:
> + pass
From the language reference:
"It is not guaranteed that __del__() methods are called for objects
that still exist when the interpreter exits."
https://docs.python.org/2.7/reference/datamodel.html#object.__del__
Relying on reference counts is risky.
The TestCase.tearDown() method is the place to clean up:
https://docs.python.org/2.7/library/unittest.html#unittest.TestCase.tearDown
It could iterate over self.bitmaps[] and call a cleanup() function.
>
> class TestIncrementalBackup(iotests.QMPTestCase):
> def setUp(self):
> @@ -73,6 +109,123 @@ class TestIncrementalBackup(iotests.QMPTestCase):
> iotests.qemu_img('create', '-f', fmt, img, size)
> self.files.append(img)
>
> +
> + def create_full_backup(self, drive=None):
> + if drive is None:
> + drive = self.drives[-1]
> +
> + res = self.vm.qmp('drive-backup', device=drive['id'],
> + sync='full', format=drive['fmt'],
> + target=drive['backup'])
> + self.assert_qmp(res, 'return', {})
> + self.wait_until_completed(drive['id'])
> + self.check_full_backup(drive)
> + self.files.append(drive['backup'])
> + return drive['backup']
> +
> +
> + def check_full_backup(self, drive=None):
> + if drive is None:
> + drive = self.drives[-1]
> + self.assertTrue(iotests.compare_images(drive['file'], drive['backup']))
I think QEMU still has at least drive['file'] open? It's not safe to
access the file from another program while it is open.
The simplest solution is to terminate the VM before calling
iotests.compare_images().
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [PATCH v4 19/20] iotests: add simple incremental backup case
2015-04-02 14:27 ` Stefan Hajnoczi
@ 2015-04-06 21:49 ` John Snow
2015-04-07 13:00 ` Stefan Hajnoczi
2015-04-13 16:51 ` Max Reitz
0 siblings, 2 replies; 54+ messages in thread
From: John Snow @ 2015-04-06 21:49 UTC (permalink / raw)
To: Stefan Hajnoczi
Cc: kwolf, famz, qemu-block, qemu-devel, armbru, vsementsov,
stefanha, mreitz
On 04/02/2015 10:27 AM, Stefan Hajnoczi wrote:
> On Fri, Mar 20, 2015 at 03:17:02PM -0400, John Snow wrote:
>> Signed-off-by: John Snow <jsnow@redhat.com>
>> ---
>> tests/qemu-iotests/124 | 153 +++++++++++++++++++++++++++++++++++++++++++++
>> tests/qemu-iotests/124.out | 4 +-
>> 2 files changed, 155 insertions(+), 2 deletions(-)
>>
>> diff --git a/tests/qemu-iotests/124 b/tests/qemu-iotests/124
>> index 85675ec..ce2cda7 100644
>> --- a/tests/qemu-iotests/124
>> +++ b/tests/qemu-iotests/124
[snip, snip, snip]
>>
>> class TestIncrementalBackup(iotests.QMPTestCase):
>> def setUp(self):
>> @@ -73,6 +109,123 @@ class TestIncrementalBackup(iotests.QMPTestCase):
>> iotests.qemu_img('create', '-f', fmt, img, size)
>> self.files.append(img)
>>
>> +
>> + def create_full_backup(self, drive=None):
>> + if drive is None:
>> + drive = self.drives[-1]
>> +
>> + res = self.vm.qmp('drive-backup', device=drive['id'],
>> + sync='full', format=drive['fmt'],
>> + target=drive['backup'])
>> + self.assert_qmp(res, 'return', {})
>> + self.wait_until_completed(drive['id'])
>> + self.check_full_backup(drive)
>> + self.files.append(drive['backup'])
>> + return drive['backup']
>> +
>> +
>> + def check_full_backup(self, drive=None):
>> + if drive is None:
>> + drive = self.drives[-1]
>> + self.assertTrue(iotests.compare_images(drive['file'], drive['backup']))
>
> I think QEMU still has at least drive['file'] open? It's not safe to
> access the file from another program while it is open.
>
> The simplest solution is to terminate the VM before calling
> iotests.compare_images().
>
Oh, that's unfortunate. I have been checking images after every creation
as a nice incremental sanity check. That will be hard to do if I have to
actually close QEMU.
My reasoning was:
(1) We're explicitly flushing after every write,
(2) We're in a qtest mode so there is no guest activity,
(3) Nobody is writing to this image by the time we call compare_images().
So it should be safe to /read/ the files while QEMU is occupied doing
nothing.
I could delay all tests until completion, but I'd lose out on the
ability to test the equivalence of any incrementals that are not their
most recent versions, unless I also start creating a lot of full
backups, but I think this starts to get messy and makes the tests hard
to follow.
Is it really that unsafe? I could add in an explicit pause/resume
barrier around the check if that would help inspire some confidence in
the test.
--js
^ permalink raw reply [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [PATCH v4 19/20] iotests: add simple incremental backup case
2015-04-06 21:49 ` John Snow
@ 2015-04-07 13:00 ` Stefan Hajnoczi
2015-04-13 16:51 ` Max Reitz
1 sibling, 0 replies; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-07 13:00 UTC (permalink / raw)
To: John Snow
Cc: kwolf, famz, qemu-block, Stefan Hajnoczi, qemu-devel, armbru,
vsementsov, mreitz
[-- Attachment #1: Type: text/plain, Size: 439 bytes --]
On Mon, Apr 06, 2015 at 05:49:10PM -0400, John Snow wrote:
> Is it really that unsafe? I could add in an explicit pause/resume barrier
> around the check if that would help inspire some confidence in the test.
There are many cases where it happens to work, but we always tell users
never to do this because we cannot guarantee it is safe.
I don't think tests should be doing something that is unsupported and
could break subtly.
Stefan
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread
* Re: [Qemu-devel] [PATCH v4 19/20] iotests: add simple incremental backup case
2015-04-06 21:49 ` John Snow
2015-04-07 13:00 ` Stefan Hajnoczi
@ 2015-04-13 16:51 ` Max Reitz
1 sibling, 0 replies; 54+ messages in thread
From: Max Reitz @ 2015-04-13 16:51 UTC (permalink / raw)
To: John Snow, Stefan Hajnoczi
Cc: kwolf, famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha
On 06.04.2015 23:49, John Snow wrote:
>
>
> On 04/02/2015 10:27 AM, Stefan Hajnoczi wrote:
>> On Fri, Mar 20, 2015 at 03:17:02PM -0400, John Snow wrote:
>>> Signed-off-by: John Snow <jsnow@redhat.com>
>>> ---
>>> tests/qemu-iotests/124 | 153
>>> +++++++++++++++++++++++++++++++++++++++++++++
>>> tests/qemu-iotests/124.out | 4 +-
>>> 2 files changed, 155 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/tests/qemu-iotests/124 b/tests/qemu-iotests/124
>>> index 85675ec..ce2cda7 100644
>>> --- a/tests/qemu-iotests/124
>>> +++ b/tests/qemu-iotests/124
>
> [snip, snip, snip]
>
>>>
>>> class TestIncrementalBackup(iotests.QMPTestCase):
>>> def setUp(self):
>>> @@ -73,6 +109,123 @@ class TestIncrementalBackup(iotests.QMPTestCase):
>>> iotests.qemu_img('create', '-f', fmt, img, size)
>>> self.files.append(img)
>>>
>>> +
>>> + def create_full_backup(self, drive=None):
>>> + if drive is None:
>>> + drive = self.drives[-1]
>>> +
>>> + res = self.vm.qmp('drive-backup', device=drive['id'],
>>> + sync='full', format=drive['fmt'],
>>> + target=drive['backup'])
>>> + self.assert_qmp(res, 'return', {})
>>> + self.wait_until_completed(drive['id'])
>>> + self.check_full_backup(drive)
>>> + self.files.append(drive['backup'])
>>> + return drive['backup']
>>> +
>>> +
>>> + def check_full_backup(self, drive=None):
>>> + if drive is None:
>>> + drive = self.drives[-1]
>>> + self.assertTrue(iotests.compare_images(drive['file'],
>>> drive['backup']))
>>
>> I think QEMU still has at least drive['file'] open? It's not safe to
>> access the file from another program while it is open.
>>
>> The simplest solution is to terminate the VM before calling
>> iotests.compare_images().
>>
>
> Oh, that's unfortunate. I have been checking images after every
> creation as a nice incremental sanity check. That will be hard to do
> if I have to actually close QEMU.
>
> My reasoning was:
>
> (1) We're explicitly flushing after every write,
> (2) We're in a qtest mode so there is no guest activity,
> (3) Nobody is writing to this image by the time we call compare_images().
>
> So it should be safe to /read/ the files while QEMU is occupied doing
> nothing.
>
> I could delay all tests until completion, but I'd lose out on the
> ability to test the equivalence of any incrementals that are not their
> most recent versions, unless I also start creating a lot of full
> backups, but I think this starts to get messy and makes the tests hard
> to follow.
>
> Is it really that unsafe? I could add in an explicit pause/resume
> barrier around the check if that would help inspire some confidence in
> the test.
I'm fine with it (and consciously accepted it while reviewing), because
the worst I can see is the test breaking. You're modifying the image and
you're checking whether the modifications are appearing in the image. I
cannot really see how qemu could not have made the modifications or made
them differently than expected, and they still appear in the image file,
just as expected.
Second, we are already relying on internal things pretty much in the
iotests (just take qemu-io, it's nothing users should ever use). So
because relying on things users shouldn't do is already a part of the
iotests and because if it doesn't work, the test will most likely just
break, I'm fine with it.
In anticipation of an "Yes, *you* can't see how the behavior can break,
making the test pass when it's actually failed, but it's not impossible,
you're relying on undefined behavior after all! Doing this even in just
a test might consume your HDD in a dragon fire!",
Max
^ permalink raw reply [flat|nested] 54+ messages in thread
* [Qemu-devel] [PATCH v4 20/20] iotests: add incremental backup failure recovery test
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (18 preceding siblings ...)
2015-03-20 19:17 ` [Qemu-devel] [PATCH v4 19/20] iotests: add simple incremental backup case John Snow
@ 2015-03-20 19:17 ` John Snow
2015-03-20 19:51 ` Max Reitz
2015-04-02 14:52 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2015-03-20 19:52 ` [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series Max Reitz
2015-04-02 14:53 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
21 siblings, 2 replies; 54+ messages in thread
From: John Snow @ 2015-03-20 19:17 UTC (permalink / raw)
To: qemu-block
Cc: kwolf, famz, John Snow, qemu-devel, armbru, vsementsov, stefanha, mreitz
Test the failure case for incremental backups.
Signed-off-by: John Snow <jsnow@redhat.com>
---
blockdev.c | 1 -
tests/qemu-iotests/124 | 55 ++++++++++++++++++++++++++++++++++++++++++++++
tests/qemu-iotests/124.out | 4 ++--
3 files changed, 57 insertions(+), 3 deletions(-)
diff --git a/blockdev.c b/blockdev.c
index b9c79ed..ab67b4d 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1218,7 +1218,6 @@ static BdrvDirtyBitmap *block_dirty_bitmap_lookup(const char *node,
} else {
aio_context_release(aio_context);
}
-
return bitmap;
fail:
diff --git a/tests/qemu-iotests/124 b/tests/qemu-iotests/124
index ce2cda7..d16d2c2 100644
--- a/tests/qemu-iotests/124
+++ b/tests/qemu-iotests/124
@@ -226,6 +226,61 @@ class TestIncrementalBackup(iotests.QMPTestCase):
return True
+ def test_incremental_failure(self):
+ '''Test: Verify backups made after a failure are correct.
+
+ Simulate a failure during an incremental backup block job,
+ emulate additional writes, then create another incremental backup
+ afterwards and verify that the backup created is correct.
+ '''
+
+ # Create a blkdebug interface to this img as 'drive1',
+ # but don't actually create a new image.
+ drive1 = self.add_node('drive1', self.drives[0]['fmt'],
+ path=self.drives[0]['file'],
+ backup=self.drives[0]['backup'])
+ result = self.vm.qmp('blockdev-add', options={
+ 'id': drive1['id'],
+ 'driver': drive1['fmt'],
+ 'file': {
+ 'driver': 'blkdebug',
+ 'image': {
+ 'driver': 'file',
+ 'filename': drive1['file']
+ },
+ 'set-state': [{
+ 'event': 'flush_to_disk',
+ 'state': 1,
+ 'new_state': 2
+ }],
+ 'inject-error': [{
+ 'event': 'read_aio',
+ 'errno': 5,
+ 'state': 2,
+ 'immediately': False,
+ 'once': True
+ }],
+ }
+ })
+ self.assert_qmp(result, 'return', {})
+
+ self.create_full_backup(self.drives[0])
+ self.add_bitmap('bitmap0', drive1)
+ # Note: at this point, during a normal execution,
+ # Assume that the VM resumes and begins issuing IO requests here.
+
+ self.hmp_io_writes(drive1['id'], (('0xab', 0, 512),
+ ('0xfe', '16M', '256k'),
+ ('0x64', '32736k', '64k')))
+
+ result = self.create_incremental(validate=False)
+ self.assertFalse(result)
+ self.hmp_io_writes(drive1['id'], (('0x9a', 0, 512),
+ ('0x55', '8M', '352k'),
+ ('0x78', '15872k', '1M')))
+ self.create_incremental()
+
+
def test_sync_dirty_bitmap_missing(self):
self.assert_no_active_block_jobs()
self.files.append(self.err_img)
diff --git a/tests/qemu-iotests/124.out b/tests/qemu-iotests/124.out
index 8d7e996..89968f3 100644
--- a/tests/qemu-iotests/124.out
+++ b/tests/qemu-iotests/124.out
@@ -1,5 +1,5 @@
-...
+....
----------------------------------------------------------------------
-Ran 3 tests
+Ran 4 tests
OK
--
2.1.0
^ permalink raw reply related [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [PATCH v4 20/20] iotests: add incremental backup failure recovery test
2015-03-20 19:17 ` [Qemu-devel] [PATCH v4 20/20] iotests: add incremental backup failure recovery test John Snow
@ 2015-03-20 19:51 ` Max Reitz
2015-04-02 14:52 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
1 sibling, 0 replies; 54+ messages in thread
From: Max Reitz @ 2015-03-20 19:51 UTC (permalink / raw)
To: John Snow, qemu-block
Cc: kwolf, famz, qemu-devel, armbru, vsementsov, stefanha
On 2015-03-20 at 15:17, John Snow wrote:
> Test the failure case for incremental backups.
>
> Signed-off-by: John Snow <jsnow@redhat.com>
> ---
> blockdev.c | 1 -
> tests/qemu-iotests/124 | 55 ++++++++++++++++++++++++++++++++++++++++++++++
> tests/qemu-iotests/124.out | 4 ++--
> 3 files changed, 57 insertions(+), 3 deletions(-)
>
> diff --git a/blockdev.c b/blockdev.c
> index b9c79ed..ab67b4d 100644
> --- a/blockdev.c
> +++ b/blockdev.c
> @@ -1218,7 +1218,6 @@ static BdrvDirtyBitmap *block_dirty_bitmap_lookup(const char *node,
> } else {
> aio_context_release(aio_context);
> }
> -
> return bitmap;
>
> fail:
This doesn't look like it belongs here...
With that hunk removed (whether by maintainer or by you):
Reviewed-by: Max Reitz <mreitz@redhat.com>
^ permalink raw reply [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH v4 20/20] iotests: add incremental backup failure recovery test
2015-03-20 19:17 ` [Qemu-devel] [PATCH v4 20/20] iotests: add incremental backup failure recovery test John Snow
2015-03-20 19:51 ` Max Reitz
@ 2015-04-02 14:52 ` Stefan Hajnoczi
1 sibling, 0 replies; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-02 14:52 UTC (permalink / raw)
To: John Snow
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
[-- Attachment #1: Type: text/plain, Size: 438 bytes --]
On Fri, Mar 20, 2015 at 03:17:03PM -0400, John Snow wrote:
> Test the failure case for incremental backups.
>
> Signed-off-by: John Snow <jsnow@redhat.com>
> ---
> blockdev.c | 1 -
> tests/qemu-iotests/124 | 55 ++++++++++++++++++++++++++++++++++++++++++++++
> tests/qemu-iotests/124.out | 4 ++--
> 3 files changed, 57 insertions(+), 3 deletions(-)
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread
* Re: [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (19 preceding siblings ...)
2015-03-20 19:17 ` [Qemu-devel] [PATCH v4 20/20] iotests: add incremental backup failure recovery test John Snow
@ 2015-03-20 19:52 ` Max Reitz
2015-03-20 19:57 ` John Snow
2015-04-02 14:53 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
21 siblings, 1 reply; 54+ messages in thread
From: Max Reitz @ 2015-03-20 19:52 UTC (permalink / raw)
To: John Snow, qemu-block
Cc: kwolf, famz, qemu-devel, armbru, vsementsov, stefanha
On 2015-03-20 at 15:16, John Snow wrote:
> I've run out of cheeky jokes for my cover letters.
>
> This patchset enables the in-memory part of the incremental backup
> feature, without transactional support.
>
> Support for transactions was separated into a separate series which
> is also now available on-list. Getting this portion of the series
> committed will help stabilize work on bitmap persistence and bitmap
> migration.
>
> Thanks to Fam Zheng for the original versions of this patchset,
> And thanks to Max for reviewing 2,395 versions of it since.
>
> ===
> v4:
> ===
>
> 04: Some in-line documentation for block_dirty_bitmap_lookup
> Changed behavior with respect to aio_context
> (always acquire, release if pbs == null, give to user otherwise)
> 10: Removed vestigial (currently nop) bdrv_enable_dirty_bitmap call
> Kept R-B.
> 16: Added some comments to test_check_boundary_bits.
> Kept R-B.
> 17: Folded in refactor from "incremental transactions v1" (Poor Kitty)
> 18: Pulled forward from "incremental transactions v1"
> Kept R-B from that series.
> 19: Folded in refactor from "incremental transactions v1"
> Added offset assertions into wait_incremental
> 20: Removed error tolerance from wait_until_completed, as
> these patches no longer make use of that feature.
Thanks for squashing the iotest refactoring code into 17, 19, and 20!
Max
^ permalink raw reply [flat|nested] 54+ messages in thread* Re: [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series
2015-03-20 19:52 ` [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series Max Reitz
@ 2015-03-20 19:57 ` John Snow
0 siblings, 0 replies; 54+ messages in thread
From: John Snow @ 2015-03-20 19:57 UTC (permalink / raw)
To: Max Reitz, qemu-block
Cc: kwolf, famz, qemu-devel, armbru, vsementsov, stefanha
On 03/20/2015 03:52 PM, Max Reitz wrote:
> On 2015-03-20 at 15:16, John Snow wrote:
>> I've run out of cheeky jokes for my cover letters.
>>
>> This patchset enables the in-memory part of the incremental backup
>> feature, without transactional support.
>>
>> Support for transactions was separated into a separate series which
>> is also now available on-list. Getting this portion of the series
>> committed will help stabilize work on bitmap persistence and bitmap
>> migration.
>>
>> Thanks to Fam Zheng for the original versions of this patchset,
>> And thanks to Max for reviewing 2,395 versions of it since.
>>
>> ===
>> v4:
>> ===
>>
>> 04: Some in-line documentation for block_dirty_bitmap_lookup
>> Changed behavior with respect to aio_context
>> (always acquire, release if pbs == null, give to user otherwise)
>> 10: Removed vestigial (currently nop) bdrv_enable_dirty_bitmap call
>> Kept R-B.
>> 16: Added some comments to test_check_boundary_bits.
>> Kept R-B.
>> 17: Folded in refactor from "incremental transactions v1" (Poor Kitty)
>> 18: Pulled forward from "incremental transactions v1"
>> Kept R-B from that series.
>> 19: Folded in refactor from "incremental transactions v1"
>> Added offset assertions into wait_incremental
>> 20: Removed error tolerance from wait_until_completed, as
>> these patches no longer make use of that feature.
>
> Thanks for squashing the iotest refactoring code into 17, 19, and 20!
>
> Max
It wound up being easier than I thought it would be at first, and it
keeps the second series smaller, so we can focus on how badly I named
everything.
--js
^ permalink raw reply [flat|nested] 54+ messages in thread
* Re: [Qemu-devel] [Qemu-block] [PATCH v4 00/20] block: transactionless incremental backup series
2015-03-20 19:16 [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series John Snow
` (20 preceding siblings ...)
2015-03-20 19:52 ` [Qemu-devel] [PATCH v4 00/20] block: transactionless incremental backup series Max Reitz
@ 2015-04-02 14:53 ` Stefan Hajnoczi
21 siblings, 0 replies; 54+ messages in thread
From: Stefan Hajnoczi @ 2015-04-02 14:53 UTC (permalink / raw)
To: John Snow
Cc: famz, qemu-block, qemu-devel, armbru, vsementsov, stefanha, mreitz
[-- Attachment #1: Type: text/plain, Size: 677 bytes --]
On Fri, Mar 20, 2015 at 03:16:43PM -0400, John Snow wrote:
> I've run out of cheeky jokes for my cover letters.
>
> This patchset enables the in-memory part of the incremental backup
> feature, without transactional support.
>
> Support for transactions was separated into a separate series which
> is also now available on-list. Getting this portion of the series
> committed will help stabilize work on bitmap persistence and bitmap
> migration.
>
> Thanks to Fam Zheng for the original versions of this patchset,
> And thanks to Max for reviewing 2,395 versions of it since.
I'm happy with the design. I posted a few questions about individual
patches.
[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]
^ permalink raw reply [flat|nested] 54+ messages in thread