Add function to cancel running async block-copy call. It will be used in backup.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> --- include/block/block-copy.h | 7 +++++++ block/block-copy.c | 22 +++++++++++++++++++--- 2 files changed, 26 insertions(+), 3 deletions(-) diff --git a/include/block/block-copy.h b/include/block/block-copy.h index d40e691123..370a194d3c 100644 --- a/include/block/block-copy.h +++ b/include/block/block-copy.h @@ -67,6 +67,13 @@ BlockCopyCallState *block_copy_async(BlockCopyState *s, void block_copy_set_speed(BlockCopyState *s, BlockCopyCallState *call_state, uint64_t speed); +/* + * Cancel running block-copy call. + * Cancel leaves block-copy state valid: dirty bits are correct and you may use + * cancel + <run block_copy with same parameters> to emulate pause/resume. + */ +void block_copy_cancel(BlockCopyCallState *call_state); + BdrvDirtyBitmap *block_copy_dirty_bitmap(BlockCopyState *s); void block_copy_set_skip_unallocated(BlockCopyState *s, bool skip); diff --git a/block/block-copy.c b/block/block-copy.c index 851d9c8aaf..b551feb6c2 100644 --- a/block/block-copy.c +++ b/block/block-copy.c @@ -44,6 +44,8 @@ typedef struct BlockCopyCallState { bool failed; bool finished; QemuCoSleepState *sleep_state; + bool cancelled; + Coroutine *canceller; /* OUT parameters */ bool error_is_read; @@ -582,7 +584,7 @@ block_copy_dirty_clusters(BlockCopyCallState *call_state) assert(QEMU_IS_ALIGNED(offset, s->cluster_size)); assert(QEMU_IS_ALIGNED(bytes, s->cluster_size)); - while (bytes && aio_task_pool_status(aio) == 0) { + while (bytes && aio_task_pool_status(aio) == 0 && !call_state->cancelled) { BlockCopyTask *task; int64_t status_bytes; @@ -693,7 +695,7 @@ static int coroutine_fn block_copy_common(BlockCopyCallState *call_state) do { ret = block_copy_dirty_clusters(call_state); - if (ret == 0) { + if (ret == 0 && !call_state->cancelled) { ret = block_copy_wait_one(call_state->s, call_state->offset, call_state->bytes); } @@ -707,13 +709,18 @@ static int coroutine_fn block_copy_common(BlockCopyCallState *call_state) * 2. We have waited for some intersecting block-copy request * It may have failed and produced new dirty bits. */ - } while (ret > 0); + } while (ret > 0 && !call_state->cancelled); if (call_state->cb) { call_state->cb(ret, call_state->error_is_read, call_state->s->progress_opaque); } + if (call_state->canceller) { + aio_co_wake(call_state->canceller); + call_state->canceller = NULL; + } + call_state->finished = true; return ret; @@ -772,6 +779,15 @@ BlockCopyCallState *block_copy_async(BlockCopyState *s, return call_state; } + +void block_copy_cancel(BlockCopyCallState *call_state) +{ + call_state->cancelled = true; + call_state->canceller = qemu_coroutine_self(); + block_copy_kick(call_state); + qemu_coroutine_yield(); +} + BdrvDirtyBitmap *block_copy_dirty_bitmap(BlockCopyState *s) { return s->copy_bitmap; -- 2.21.0