The two callers to a mirror job (drive-mirror and blockdev-mirror) set
zero_target precisely when sync mode == FULL, with the one exception
that drive-mirror skips zeroing the target if it was newly created and
reads as zero. But given the previous patch, that exception is
equally captured by target_is_zero. And since we recently updated
things to pass the sync mode all the way through to
mirror_dirty_init(), we can now reconstruct the same conditionals
without the redundant parameter.
Signed-off-by: Eric Blake <ebl...@redhat.com>
---
v4: new patch
---
include/block/block_int-global-state.h | 3 +--
block/mirror.c | 13 +++++--------
blockdev.c | 15 ++++-----------
tests/unit/test-block-iothread.c | 2 +-
4 files changed, 11 insertions(+), 22 deletions(-)
diff --git a/include/block/block_int-global-state.h
b/include/block/block_int-global-state.h
index 8cf0003ce78..d21bd7fd2f5 100644
--- a/include/block/block_int-global-state.h
+++ b/include/block/block_int-global-state.h
@@ -139,7 +139,6 @@ BlockJob *commit_active_start(const char *job_id,
BlockDriverState *bs,
* @buf_size: The amount of data that can be in flight at one time.
* @mode: Whether to collapse all images in the chain to the target.
* @backing_mode: How to establish the target's backing chain after completion.
- * @zero_target: Whether the target should be explicitly zero-initialized
* @target_is_zero: Whether the target already is zero-initialized.
* @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.
@@ -160,7 +159,7 @@ void mirror_start(const char *job_id, BlockDriverState *bs,
int creation_flags, int64_t speed,
uint32_t granularity, int64_t buf_size,
MirrorSyncMode mode, BlockMirrorBackingMode backing_mode,
- bool zero_target, bool target_is_zero,
+ bool target_is_zero,
BlockdevOnError on_source_error,
BlockdevOnError on_target_error,
bool unmap, const char *filter_node_name,
diff --git a/block/mirror.c b/block/mirror.c
index 4dcb50c81ad..d04db85883d 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -53,8 +53,6 @@ typedef struct MirrorBlockJob {
Error *replace_blocker;
MirrorSyncMode sync_mode;
BlockMirrorBackingMode backing_mode;
- /* Whether the target image requires explicit zero-initialization */
- bool zero_target;
/* Whether the target should be assumed to be already zero initialized */
bool target_is_zero;
/*
@@ -854,7 +852,9 @@ static int coroutine_fn GRAPH_UNLOCKED
mirror_dirty_init(MirrorBlockJob *s)
bs = s->mirror_top_bs->backing->bs;
bdrv_graph_co_rdunlock();
- if (s->zero_target && (!s->target_is_zero || punch_holes)) {
+ if (s->sync_mode == MIRROR_SYNC_MODE_TOP) {
+ /* In TOP mode, there is no benefit to a pre-zeroing pass. */
+ } else if (!s->target_is_zero || punch_holes) {
/*
* Here, we are in FULL mode; our goal is to avoid writing
* zeroes if the destination already reads as zero, except
@@ -1730,7 +1730,7 @@ static BlockJob *mirror_start_job(
uint32_t granularity, int64_t buf_size,
MirrorSyncMode sync_mode,
BlockMirrorBackingMode backing_mode,
- bool zero_target, bool target_is_zero,
+ bool target_is_zero,
BlockdevOnError on_source_error,
BlockdevOnError on_target_error,
bool unmap,
@@ -1898,7 +1898,6 @@ static BlockJob *mirror_start_job(
s->on_target_error = on_target_error;
s->sync_mode = sync_mode;
s->backing_mode = backing_mode;
- s->zero_target = zero_target;
s->target_is_zero = target_is_zero;
qatomic_set(&s->copy_mode, copy_mode);
s->base = base;
@@ -2028,7 +2027,7 @@ void mirror_start(const char *job_id, BlockDriverState
*bs,
int creation_flags, int64_t speed,
uint32_t granularity, int64_t buf_size,
MirrorSyncMode mode, BlockMirrorBackingMode backing_mode,
- bool zero_target, bool target_is_zero,
+ bool target_is_zero,
BlockdevOnError on_source_error,
BlockdevOnError on_target_error,
bool unmap, const char *filter_node_name,
@@ -2051,7 +2050,6 @@ void mirror_start(const char *job_id, BlockDriverState
*bs,
mirror_start_job(job_id, bs, creation_flags, target, replaces,
speed, granularity, buf_size, mode, backing_mode,
- zero_target,
target_is_zero, on_source_error, on_target_error, unmap,
NULL, NULL, &mirror_job_driver, base, false,
filter_node_name, true, copy_mode, false, errp);
@@ -2080,7 +2078,6 @@ BlockJob *commit_active_start(const char *job_id,
BlockDriverState *bs,
job = mirror_start_job(
job_id, bs, creation_flags, base, NULL, speed, 0, 0,
MIRROR_SYNC_MODE_TOP, MIRROR_LEAVE_BACKING_CHAIN, false,
- false,
on_error, on_error, true, cb, opaque,
&commit_active_job_driver, base, auto_complete,
filter_node_name, false, MIRROR_COPY_MODE_BACKGROUND,
diff --git a/blockdev.c b/blockdev.c
index 2e2fed539ee..7eb1ffb6396 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -2798,7 +2798,7 @@ static void blockdev_mirror_common(const char *job_id,
BlockDriverState *bs,
const char *replaces,
enum MirrorSyncMode sync,
BlockMirrorBackingMode backing_mode,
- bool zero_target, bool target_is_zero,
+ bool target_is_zero,
bool has_speed, int64_t speed,
bool has_granularity, uint32_t granularity,
bool has_buf_size, int64_t buf_size,
@@ -2910,7 +2910,7 @@ static void blockdev_mirror_common(const char *job_id,
BlockDriverState *bs,
* and will allow to check whether the node still exist at mirror
completion
*/
mirror_start(job_id, bs, target, replaces, job_flags,
- speed, granularity, buf_size, sync, backing_mode, zero_target,
+ speed, granularity, buf_size, sync, backing_mode,
target_is_zero, on_source_error, on_target_error, unmap,
filter_node_name, copy_mode, errp);
}
@@ -2926,7 +2926,6 @@ void qmp_drive_mirror(DriveMirror *arg, Error **errp)
int flags;
int64_t size;
const char *format = arg->format;
- bool zero_target;
bool target_is_zero;
int ret;
@@ -3041,9 +3040,6 @@ void qmp_drive_mirror(DriveMirror *arg, Error **errp)
}
bdrv_graph_rdlock_main_loop();
- zero_target = (arg->sync == MIRROR_SYNC_MODE_FULL &&
- (arg->mode == NEW_IMAGE_MODE_EXISTING ||
- !bdrv_has_zero_init(target_bs)));
target_is_zero = (arg->mode != NEW_IMAGE_MODE_EXISTING &&
bdrv_has_zero_init(target_bs));
bdrv_graph_rdunlock_main_loop();
@@ -3057,7 +3053,7 @@ void qmp_drive_mirror(DriveMirror *arg, Error **errp)
blockdev_mirror_common(arg->job_id, bs, target_bs,
arg->replaces, arg->sync,
- backing_mode, zero_target, target_is_zero,
+ backing_mode, target_is_zero,
arg->has_speed, arg->speed,
arg->has_granularity, arg->granularity,
arg->has_buf_size, arg->buf_size,
@@ -3094,7 +3090,6 @@ void qmp_blockdev_mirror(const char *job_id,
BlockDriverState *target_bs;
AioContext *aio_context;
BlockMirrorBackingMode backing_mode = MIRROR_LEAVE_BACKING_CHAIN;
- bool zero_target;
int ret;
bs = qmp_get_root_bs(device, errp);
@@ -3107,8 +3102,6 @@ void qmp_blockdev_mirror(const char *job_id,
return;
}
- zero_target = (sync == MIRROR_SYNC_MODE_FULL);
-
aio_context = bdrv_get_aio_context(bs);
ret = bdrv_try_change_aio_context(target_bs, aio_context, NULL, errp);
@@ -3118,7 +3111,7 @@ void qmp_blockdev_mirror(const char *job_id,
blockdev_mirror_common(job_id, bs, target_bs,
replaces, sync, backing_mode,
- zero_target, has_target_is_zero && target_is_zero,
+ has_target_is_zero && target_is_zero,
has_speed, speed,
has_granularity, granularity,
has_buf_size, buf_size,
diff --git a/tests/unit/test-block-iothread.c b/tests/unit/test-block-iothread.c
index 54aed8252c0..e26b3be5939 100644
--- a/tests/unit/test-block-iothread.c
+++ b/tests/unit/test-block-iothread.c
@@ -755,7 +755,7 @@ static void test_propagate_mirror(void)
/* Start a mirror job */
mirror_start("job0", src, target, NULL, JOB_DEFAULT, 0, 0, 0,
- MIRROR_SYNC_MODE_NONE, MIRROR_OPEN_BACKING_CHAIN, false,
false,
+ MIRROR_SYNC_MODE_NONE, MIRROR_OPEN_BACKING_CHAIN, false,
BLOCKDEV_ON_ERROR_REPORT, BLOCKDEV_ON_ERROR_REPORT,
false, "filter_node", MIRROR_COPY_MODE_BACKGROUND,
&error_abort);
--
2.49.0
