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