This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_co_block_status() need to hold a reader lock for the graph.
For some places, we know that they will hold the lock, but we don't have the GRAPH_RDLOCK annotations yet. In this case, add assume_graph_lock() with a FIXME comment. These places will be removed once everything is properly annotated. Signed-off-by: Emanuele Giuseppe Esposito <eespo...@redhat.com> Signed-off-by: Kevin Wolf <kw...@redhat.com> Message-Id: <20230203152202.49054-5-kw...@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eespo...@redhat.com> Signed-off-by: Kevin Wolf <kw...@redhat.com> --- block/coroutines.h | 2 +- include/block/block-copy.h | 6 +++--- include/block/block-io.h | 22 +++++++++++----------- include/block/block_int-common.h | 3 ++- block/backup.c | 3 +++ block/block-backend.c | 2 ++ block/block-copy.c | 19 +++++++++++-------- block/io.c | 13 ++++++++----- block/mirror.c | 14 +++++++++----- block/qcow.c | 11 ++++------- block/quorum.c | 9 ++++----- block/stream.c | 32 ++++++++++++++++++-------------- qemu-img.c | 4 +++- tests/unit/test-block-iothread.c | 3 ++- 14 files changed, 81 insertions(+), 62 deletions(-) diff --git a/block/coroutines.h b/block/coroutines.h index 2a1e0b3c9d..dd9f3d449b 100644 --- a/block/coroutines.h +++ b/block/coroutines.h @@ -43,7 +43,7 @@ bdrv_co_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix); int coroutine_fn GRAPH_RDLOCK bdrv_co_invalidate_cache(BlockDriverState *bs, Error **errp); -int coroutine_fn +int coroutine_fn GRAPH_RDLOCK bdrv_co_common_block_status_above(BlockDriverState *bs, BlockDriverState *base, bool include_base, diff --git a/include/block/block-copy.h b/include/block/block-copy.h index d0f8386554..0700953ab8 100644 --- a/include/block/block-copy.h +++ b/include/block/block-copy.h @@ -36,9 +36,9 @@ void block_copy_set_progress_meter(BlockCopyState *s, ProgressMeter *pm); void block_copy_state_free(BlockCopyState *s); void block_copy_reset(BlockCopyState *s, int64_t offset, int64_t bytes); -int64_t coroutine_fn block_copy_reset_unallocated(BlockCopyState *s, - int64_t offset, - int64_t *count); + +int64_t coroutine_fn GRAPH_RDLOCK +block_copy_reset_unallocated(BlockCopyState *s, int64_t offset, int64_t *count); int coroutine_fn block_copy(BlockCopyState *s, int64_t offset, int64_t bytes, bool ignore_ratelimit, uint64_t timeout_ns, diff --git a/include/block/block-io.h b/include/block/block-io.h index 9a09ec2bdd..6303501b0f 100644 --- a/include/block/block-io.h +++ b/include/block/block-io.h @@ -109,24 +109,24 @@ int bdrv_block_status(BlockDriverState *bs, int64_t offset, int64_t bytes, int64_t *pnum, int64_t *map, BlockDriverState **file); -int coroutine_fn bdrv_co_block_status_above(BlockDriverState *bs, - BlockDriverState *base, - int64_t offset, int64_t bytes, - int64_t *pnum, int64_t *map, - BlockDriverState **file); +int coroutine_fn GRAPH_RDLOCK +bdrv_co_block_status_above(BlockDriverState *bs, BlockDriverState *base, + int64_t offset, int64_t bytes, int64_t *pnum, + int64_t *map, BlockDriverState **file); int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base, int64_t offset, int64_t bytes, int64_t *pnum, int64_t *map, BlockDriverState **file); -int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs, int64_t offset, - int64_t bytes, int64_t *pnum); +int coroutine_fn GRAPH_RDLOCK +bdrv_co_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, + int64_t *pnum); int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, int64_t *pnum); -int coroutine_fn bdrv_co_is_allocated_above(BlockDriverState *top, - BlockDriverState *base, - bool include_base, int64_t offset, - int64_t bytes, int64_t *pnum); +int coroutine_fn GRAPH_RDLOCK +bdrv_co_is_allocated_above(BlockDriverState *top, BlockDriverState *base, + bool include_base, int64_t offset, int64_t bytes, + int64_t *pnum); int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base, bool include_base, int64_t offset, int64_t bytes, int64_t *pnum); diff --git a/include/block/block_int-common.h b/include/block/block_int-common.h index eaf62beaff..5f0104a1af 100644 --- a/include/block/block_int-common.h +++ b/include/block/block_int-common.h @@ -606,7 +606,8 @@ struct BlockDriver { * *pnum value for the block-status cache on protocol nodes, prior * to clamping *pnum for return to its caller. */ - int coroutine_fn (*bdrv_co_block_status)(BlockDriverState *bs, + int coroutine_fn GRAPH_RDLOCK_PTR (*bdrv_co_block_status)( + BlockDriverState *bs, bool want_zero, int64_t offset, int64_t bytes, int64_t *pnum, int64_t *map, BlockDriverState **file); diff --git a/block/backup.c b/block/backup.c index 824d39acaa..46fca2459d 100644 --- a/block/backup.c +++ b/block/backup.c @@ -270,7 +270,10 @@ static int coroutine_fn backup_run(Job *job, Error **errp) return -ECANCELED; } + /* rdlock protects the subsequent call to bdrv_is_allocated() */ + bdrv_graph_co_rdlock(); ret = block_copy_reset_unallocated(s->bcs, offset, &count); + bdrv_graph_co_rdunlock(); if (ret < 0) { return ret; } diff --git a/block/block-backend.c b/block/block-backend.c index f25f3ba5e7..f5d9e3e269 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -1431,6 +1431,7 @@ int coroutine_fn blk_co_block_status_above(BlockBackend *blk, BlockDriverState **file) { IO_CODE(); + GRAPH_RDLOCK_GUARD(); return bdrv_co_block_status_above(blk_bs(blk), base, offset, bytes, pnum, map, file); } @@ -1441,6 +1442,7 @@ int coroutine_fn blk_co_is_allocated_above(BlockBackend *blk, int64_t bytes, int64_t *pnum) { IO_CODE(); + GRAPH_RDLOCK_GUARD(); return bdrv_co_is_allocated_above(blk_bs(blk), base, include_base, offset, bytes, pnum); } diff --git a/block/block-copy.c b/block/block-copy.c index 30a4da0f2e..d299fac7cc 100644 --- a/block/block-copy.c +++ b/block/block-copy.c @@ -581,9 +581,9 @@ static coroutine_fn int block_copy_task_entry(AioTask *task) return ret; } -static coroutine_fn int block_copy_block_status(BlockCopyState *s, - int64_t offset, - int64_t bytes, int64_t *pnum) +static coroutine_fn GRAPH_RDLOCK +int block_copy_block_status(BlockCopyState *s, int64_t offset, int64_t bytes, + int64_t *pnum) { int64_t num; BlockDriverState *base; @@ -618,9 +618,9 @@ static coroutine_fn int block_copy_block_status(BlockCopyState *s, * Check if the cluster starting at offset is allocated or not. * return via pnum the number of contiguous clusters sharing this allocation. */ -static int coroutine_fn block_copy_is_cluster_allocated(BlockCopyState *s, - int64_t offset, - int64_t *pnum) +static int coroutine_fn GRAPH_RDLOCK +block_copy_is_cluster_allocated(BlockCopyState *s, int64_t offset, + int64_t *pnum) { BlockDriverState *bs = s->source->bs; int64_t count, total_count = 0; @@ -630,6 +630,7 @@ static int coroutine_fn block_copy_is_cluster_allocated(BlockCopyState *s, assert(QEMU_IS_ALIGNED(offset, s->cluster_size)); while (true) { + /* protected in backup_run() */ ret = bdrv_co_is_allocated(bs, offset, bytes, &count); if (ret < 0) { return ret; @@ -704,7 +705,7 @@ int64_t coroutine_fn block_copy_reset_unallocated(BlockCopyState *s, * Returns 1 if dirty clusters found and successfully copied, 0 if no dirty * clusters found and -errno on failure. */ -static int coroutine_fn +static int coroutine_fn GRAPH_RDLOCK block_copy_dirty_clusters(BlockCopyCallState *call_state) { BlockCopyState *s = call_state->s; @@ -827,7 +828,8 @@ void block_copy_kick(BlockCopyCallState *call_state) * it means that some I/O operation failed in context of _this_ block_copy call, * not some parallel operation. */ -static int coroutine_fn block_copy_common(BlockCopyCallState *call_state) +static int coroutine_fn GRAPH_RDLOCK +block_copy_common(BlockCopyCallState *call_state) { int ret; BlockCopyState *s = call_state->s; @@ -892,6 +894,7 @@ static int coroutine_fn block_copy_common(BlockCopyCallState *call_state) static void coroutine_fn block_copy_async_co_entry(void *opaque) { + GRAPH_RDLOCK_GUARD(); block_copy_common(opaque); } diff --git a/block/io.c b/block/io.c index 35025fc11b..a0f8efc9a1 100644 --- a/block/io.c +++ b/block/io.c @@ -2224,11 +2224,10 @@ int bdrv_flush_all(void) * BDRV_BLOCK_OFFSET_VALID bit is set, 'map' and 'file' (if non-NULL) are * set to the host mapping and BDS corresponding to the guest offset. */ -static int coroutine_fn bdrv_co_block_status(BlockDriverState *bs, - bool want_zero, - int64_t offset, int64_t bytes, - int64_t *pnum, int64_t *map, - BlockDriverState **file) +static int coroutine_fn GRAPH_RDLOCK +bdrv_co_block_status(BlockDriverState *bs, bool want_zero, + int64_t offset, int64_t bytes, + int64_t *pnum, int64_t *map, BlockDriverState **file) { int64_t total_size; int64_t n; /* bytes */ @@ -2240,6 +2239,7 @@ static int coroutine_fn bdrv_co_block_status(BlockDriverState *bs, bool has_filtered_child; assert(pnum); + assert_bdrv_graph_readable(); *pnum = 0; total_size = bdrv_getlength(bs); if (total_size < 0) { @@ -2470,6 +2470,7 @@ bdrv_co_common_block_status_above(BlockDriverState *bs, IO_CODE(); assert(!include_base || base); /* Can't include NULL base */ + assert_bdrv_graph_readable(); if (!depth) { depth = &dummy; @@ -2595,6 +2596,8 @@ int coroutine_fn bdrv_co_is_zero_fast(BlockDriverState *bs, int64_t offset, int64_t pnum = bytes; IO_CODE(); + assume_graph_lock(); /* FIXME */ + if (!bytes) { return 1; } diff --git a/block/mirror.c b/block/mirror.c index fbbb4f619e..94c523af28 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -558,9 +558,11 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s) MirrorMethod mirror_method = MIRROR_METHOD_COPY; assert(!(offset % s->granularity)); - ret = bdrv_block_status_above(source, NULL, offset, - nb_chunks * s->granularity, - &io_bytes, NULL, NULL); + WITH_GRAPH_RDLOCK_GUARD() { + ret = bdrv_block_status_above(source, NULL, offset, + nb_chunks * s->granularity, + &io_bytes, NULL, NULL); + } if (ret < 0) { io_bytes = MIN(nb_chunks * s->granularity, max_io_bytes); } else if (ret & BDRV_BLOCK_DATA) { @@ -863,8 +865,10 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s) return 0; } - ret = bdrv_is_allocated_above(bs, s->base_overlay, true, offset, bytes, - &count); + WITH_GRAPH_RDLOCK_GUARD() { + ret = bdrv_is_allocated_above(bs, s->base_overlay, true, offset, + bytes, &count); + } if (ret < 0) { return ret; } diff --git a/block/qcow.c b/block/qcow.c index 5eb1ab5e59..2d19a78818 100644 --- a/block/qcow.c +++ b/block/qcow.c @@ -524,19 +524,16 @@ get_cluster_offset(BlockDriverState *bs, uint64_t offset, int allocate, return 1; } -static int coroutine_fn qcow_co_block_status(BlockDriverState *bs, - bool want_zero, - int64_t offset, int64_t bytes, - int64_t *pnum, int64_t *map, - BlockDriverState **file) +static int coroutine_fn GRAPH_RDLOCK +qcow_co_block_status(BlockDriverState *bs, bool want_zero, + int64_t offset, int64_t bytes, int64_t *pnum, + int64_t *map, BlockDriverState **file) { BDRVQcowState *s = bs->opaque; int index_in_cluster, ret; int64_t n; uint64_t cluster_offset; - assume_graph_lock(); /* FIXME */ - qemu_co_mutex_lock(&s->lock); ret = get_cluster_offset(bs, offset, 0, 0, 0, 0, &cluster_offset); qemu_co_mutex_unlock(&s->lock); diff --git a/block/quorum.c b/block/quorum.c index d1dcf2eaba..f3fe067541 100644 --- a/block/quorum.c +++ b/block/quorum.c @@ -1217,11 +1217,10 @@ static void quorum_child_perm(BlockDriverState *bs, BdrvChild *c, * return BDRV_BLOCK_ZERO if *all* children agree that a certain * region contains zeroes, and BDRV_BLOCK_DATA otherwise. */ -static int coroutine_fn quorum_co_block_status(BlockDriverState *bs, - bool want_zero, - int64_t offset, int64_t count, - int64_t *pnum, int64_t *map, - BlockDriverState **file) +static int coroutine_fn GRAPH_RDLOCK +quorum_co_block_status(BlockDriverState *bs, bool want_zero, + int64_t offset, int64_t count, + int64_t *pnum, int64_t *map, BlockDriverState **file) { BDRVQuorumState *s = bs->opaque; int i, ret; diff --git a/block/stream.c b/block/stream.c index 8744ad103f..22368ce186 100644 --- a/block/stream.c +++ b/block/stream.c @@ -161,21 +161,25 @@ static int coroutine_fn stream_run(Job *job, Error **errp) copy = false; - ret = bdrv_is_allocated(unfiltered_bs, offset, STREAM_CHUNK, &n); - if (ret == 1) { - /* Allocated in the top, no need to copy. */ - } else if (ret >= 0) { - /* Copy if allocated in the intermediate images. Limit to the - * known-unallocated area [offset, offset+n*BDRV_SECTOR_SIZE). */ - ret = bdrv_is_allocated_above(bdrv_cow_bs(unfiltered_bs), - s->base_overlay, true, - offset, n, &n); - /* Finish early if end of backing file has been reached */ - if (ret == 0 && n == 0) { - n = len - offset; + WITH_GRAPH_RDLOCK_GUARD() { + ret = bdrv_is_allocated(unfiltered_bs, offset, STREAM_CHUNK, &n); + if (ret == 1) { + /* Allocated in the top, no need to copy. */ + } else if (ret >= 0) { + /* + * Copy if allocated in the intermediate images. Limit to the + * known-unallocated area [offset, offset+n*BDRV_SECTOR_SIZE). + */ + ret = bdrv_is_allocated_above(bdrv_cow_bs(unfiltered_bs), + s->base_overlay, true, + offset, n, &n); + /* Finish early if end of backing file has been reached */ + if (ret == 0 && n == 0) { + n = len - offset; + } + + copy = (ret > 0); } - - copy = (ret > 0); } trace_stream_one_iteration(s, offset, n, ret); if (copy) { diff --git a/qemu-img.c b/qemu-img.c index 7c05931866..cd0178b51b 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -1991,7 +1991,9 @@ static void coroutine_fn convert_co_do_copy(void *opaque) qemu_co_mutex_unlock(&s->lock); break; } - n = convert_iteration_sectors(s, s->sector_num); + WITH_GRAPH_RDLOCK_GUARD() { + n = convert_iteration_sectors(s, s->sector_num); + } if (n < 0) { qemu_co_mutex_unlock(&s->lock); s->ret = n; diff --git a/tests/unit/test-block-iothread.c b/tests/unit/test-block-iothread.c index 6dfac6468a..3a5e1eb2c4 100644 --- a/tests/unit/test-block-iothread.c +++ b/tests/unit/test-block-iothread.c @@ -312,7 +312,8 @@ static void test_sync_op_blk_truncate(BlockBackend *blk) g_assert_cmpint(ret, ==, -EINVAL); } -static void test_sync_op_block_status(BdrvChild *c) +/* Disable TSA to make bdrv_test.bdrv_co_block_status writable */ +static void TSA_NO_TSA test_sync_op_block_status(BdrvChild *c) { int ret; int64_t n; -- 2.39.2