diff options
| -rw-r--r-- | block/mirror.c | 27 | ||||
| -rw-r--r-- | blockdev.c | 18 | ||||
| -rw-r--r-- | include/block/block_int-global-state.h | 3 | ||||
| -rw-r--r-- | qapi/block-core.json | 8 | ||||
| -rw-r--r-- | tests/unit/test-block-iothread.c | 2 |
5 files changed, 44 insertions, 14 deletions
diff --git a/block/mirror.c b/block/mirror.c index 2599b75d09..4dcb50c81a 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -55,6 +55,8 @@ typedef struct MirrorBlockJob { 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; /* * To be accesssed with atomics. Written only under the BQL (required by the * current implementation of mirror_change()). @@ -844,12 +846,26 @@ static int coroutine_fn GRAPH_UNLOCKED mirror_dirty_init(MirrorBlockJob *s) BlockDriverState *target_bs = blk_bs(s->target); int ret = -EIO; int64_t count; + bool punch_holes = + target_bs->detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && + bdrv_can_write_zeroes_with_unmap(target_bs); bdrv_graph_co_rdlock(); bs = s->mirror_top_bs->backing->bs; bdrv_graph_co_rdunlock(); - if (s->zero_target) { + if (s->zero_target && (!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 + * when we are trying to punch holes. This is possible if + * zeroing happened externally (s->target_is_zero) or if we + * have a fast way to pre-zero the image (the dirty bitmap + * will be populated later by the non-zero portions, the same + * as for TOP mode). If pre-zeroing is not fast, or we need + * to punch holes, then our only recourse is to write the + * entire image. + */ if (!bdrv_can_write_zeroes_with_unmap(target_bs)) { bdrv_set_dirty_bitmap(s->dirty_bitmap, 0, s->bdev_length); return 0; @@ -1714,7 +1730,7 @@ static BlockJob *mirror_start_job( uint32_t granularity, int64_t buf_size, MirrorSyncMode sync_mode, BlockMirrorBackingMode backing_mode, - bool zero_target, + bool zero_target, bool target_is_zero, BlockdevOnError on_source_error, BlockdevOnError on_target_error, bool unmap, @@ -1883,6 +1899,7 @@ static BlockJob *mirror_start_job( 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; s->base_overlay = bdrv_find_overlay(bs, base); @@ -2011,7 +2028,7 @@ 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 zero_target, bool target_is_zero, BlockdevOnError on_source_error, BlockdevOnError on_target_error, bool unmap, const char *filter_node_name, @@ -2034,7 +2051,8 @@ 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, on_source_error, on_target_error, unmap, + 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); } @@ -2062,6 +2080,7 @@ 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 818ec42511..97128feb27 100644 --- a/blockdev.c +++ b/blockdev.c @@ -2804,7 +2804,7 @@ static void blockdev_mirror_common(const char *job_id, BlockDriverState *bs, const char *replaces, enum MirrorSyncMode sync, BlockMirrorBackingMode backing_mode, - bool zero_target, + bool zero_target, bool target_is_zero, bool has_speed, int64_t speed, bool has_granularity, uint32_t granularity, bool has_buf_size, int64_t buf_size, @@ -2915,11 +2915,10 @@ static void blockdev_mirror_common(const char *job_id, BlockDriverState *bs, /* pass the node name to replace to mirror start since it's loose coupling * and will allow to check whether the node still exist at mirror completion */ - mirror_start(job_id, bs, target, - replaces, job_flags, + mirror_start(job_id, bs, target, replaces, job_flags, speed, granularity, buf_size, sync, backing_mode, zero_target, - on_source_error, on_target_error, unmap, filter_node_name, - copy_mode, errp); + target_is_zero, on_source_error, on_target_error, unmap, + filter_node_name, copy_mode, errp); } void qmp_drive_mirror(DriveMirror *arg, Error **errp) @@ -2934,6 +2933,7 @@ void qmp_drive_mirror(DriveMirror *arg, Error **errp) int64_t size; const char *format = arg->format; bool zero_target; + bool target_is_zero; int ret; bs = qmp_get_root_bs(arg->device, errp); @@ -3050,6 +3050,8 @@ void qmp_drive_mirror(DriveMirror *arg, Error **errp) 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(); @@ -3061,7 +3063,7 @@ 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, + backing_mode, zero_target, target_is_zero, arg->has_speed, arg->speed, arg->has_granularity, arg->granularity, arg->has_buf_size, arg->buf_size, @@ -3091,6 +3093,7 @@ void qmp_blockdev_mirror(const char *job_id, bool has_copy_mode, MirrorCopyMode copy_mode, bool has_auto_finalize, bool auto_finalize, bool has_auto_dismiss, bool auto_dismiss, + bool has_target_is_zero, bool target_is_zero, Error **errp) { BlockDriverState *bs; @@ -3121,7 +3124,8 @@ void qmp_blockdev_mirror(const char *job_id, blockdev_mirror_common(job_id, bs, target_bs, replaces, sync, backing_mode, - zero_target, has_speed, speed, + zero_target, has_target_is_zero && target_is_zero, + has_speed, speed, has_granularity, granularity, has_buf_size, buf_size, has_on_source_error, on_source_error, diff --git a/include/block/block_int-global-state.h b/include/block/block_int-global-state.h index 0d93783763..62a6c7e8e2 100644 --- a/include/block/block_int-global-state.h +++ b/include/block/block_int-global-state.h @@ -140,6 +140,7 @@ BlockJob *commit_active_start(const char *job_id, BlockDriverState *bs, * @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. * @unmap: Whether to unmap target where source sectors only contain zeroes. @@ -159,7 +160,7 @@ 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 zero_target, bool target_is_zero, BlockdevOnError on_source_error, BlockdevOnError on_target_error, bool unmap, const char *filter_node_name, diff --git a/qapi/block-core.json b/qapi/block-core.json index 91c70e24a7..b4115113d4 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -2542,6 +2542,11 @@ # disappear from the query list without user intervention. # Defaults to true. (Since 3.1) # +# @target-is-zero: Assume the destination reads as all zeroes before +# the mirror started. Setting this to true can speed up the +# mirror. Setting this to true when the destination is not +# actually all zero can corrupt the destination. (Since 10.1) +# # Since: 2.6 # # .. qmp-example:: @@ -2561,7 +2566,8 @@ '*on-target-error': 'BlockdevOnError', '*filter-node-name': 'str', '*copy-mode': 'MirrorCopyMode', - '*auto-finalize': 'bool', '*auto-dismiss': 'bool' }, + '*auto-finalize': 'bool', '*auto-dismiss': 'bool', + '*target-is-zero': 'bool'}, 'allow-preconfig': true } ## diff --git a/tests/unit/test-block-iothread.c b/tests/unit/test-block-iothread.c index e26b3be593..54aed8252c 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, + MIRROR_SYNC_MODE_NONE, MIRROR_OPEN_BACKING_CHAIN, false, false, BLOCKDEV_ON_ERROR_REPORT, BLOCKDEV_ON_ERROR_REPORT, false, "filter_node", MIRROR_COPY_MODE_BACKGROUND, &error_abort); |