From ad74751fc0ffdad7678224df0e752689ebb3f4b7 Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Fri, 27 Oct 2023 17:53:17 +0200 Subject: block: Mark bdrv_skip_filters() and callers GRAPH_RDLOCK This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_skip_filters() need to hold a reader lock for the graph because it calls bdrv_filter_child(), which accesses bs->file/backing. Signed-off-by: Kevin Wolf Message-ID: <20231027155333.420094-9-kwolf@redhat.com> Reviewed-by: Eric Blake Signed-off-by: Kevin Wolf --- qemu-img.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) (limited to 'qemu-img.c') diff --git a/qemu-img.c b/qemu-img.c index c061fd0..33f3ab5 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -1050,12 +1050,14 @@ static int img_commit(int argc, char **argv) qemu_progress_init(progress, 1.f); qemu_progress_print(0.f, 100); + bdrv_graph_rdlock_main_loop(); if (base) { base_bs = bdrv_find_backing_image(bs, base); if (!base_bs) { error_setg(&local_err, "Did not find '%s' in the backing chain of '%s'", base, filename); + bdrv_graph_rdunlock_main_loop(); goto done; } } else { @@ -1065,9 +1067,11 @@ static int img_commit(int argc, char **argv) base_bs = bdrv_backing_chain_next(bs); if (!base_bs) { error_setg(&local_err, "Image does not have a backing file"); + bdrv_graph_rdunlock_main_loop(); goto done; } } + bdrv_graph_rdunlock_main_loop(); cbi = (CommonBlockJobCBInfo){ .errp = &local_err, @@ -1713,7 +1717,8 @@ static void convert_select_part(ImgConvertState *s, int64_t sector_num, } } -static int convert_iteration_sectors(ImgConvertState *s, int64_t sector_num) +static int coroutine_mixed_fn GRAPH_RDLOCK +convert_iteration_sectors(ImgConvertState *s, int64_t sector_num) { int64_t src_cur_offset; int ret, n, src_cur; @@ -2115,7 +2120,9 @@ static int convert_do_copy(ImgConvertState *s) } while (sector_num < s->total_sectors) { + bdrv_graph_rdlock_main_loop(); n = convert_iteration_sectors(s, sector_num); + bdrv_graph_rdunlock_main_loop(); if (n < 0) { return n; } @@ -2757,8 +2764,10 @@ static int img_convert(int argc, char **argv) * s.target_backing_sectors has to be negative, which it will * be automatically). The backing file length is used only * for optimizations, so such a case is not fatal. */ + bdrv_graph_rdlock_main_loop(); s.target_backing_sectors = bdrv_nb_sectors(bdrv_backing_chain_next(out_bs)); + bdrv_graph_rdunlock_main_loop(); } else { s.target_backing_sectors = -1; } @@ -3145,6 +3154,9 @@ static int get_block_status(BlockDriverState *bs, int64_t offset, int64_t map; char *filename = NULL; + GLOBAL_STATE_CODE(); + GRAPH_RDLOCK_GUARD_MAINLOOP(); + /* As an optimization, we could cache the current range of unallocated * clusters in each file of the chain, and avoid querying the same * range repeatedly. @@ -3173,9 +3185,7 @@ static int get_block_status(BlockDriverState *bs, int64_t offset, has_offset = !!(ret & BDRV_BLOCK_OFFSET_VALID); if (file && has_offset) { - bdrv_graph_rdlock_main_loop(); bdrv_refresh_filename(file); - bdrv_graph_rdunlock_main_loop(); filename = file->filename; } @@ -3663,7 +3673,9 @@ static int img_rebase(int argc, char **argv) } bs = blk_bs(blk); + bdrv_graph_rdlock_main_loop(); unfiltered_bs = bdrv_skip_filters(bs); + bdrv_graph_rdunlock_main_loop(); if (compress && !block_driver_can_compress(unfiltered_bs->drv)) { error_report("Compression not supported for this file format"); -- cgit v1.1