From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34465) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cv4Ym-0001Ht-Ux for qemu-devel@nongnu.org; Mon, 03 Apr 2017 12:10:30 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cv4Ym-0000R8-1h for qemu-devel@nongnu.org; Mon, 03 Apr 2017 12:10:28 -0400 From: Max Reitz Date: Mon, 3 Apr 2017 18:09:30 +0200 Message-Id: <20170403160936.28293-11-mreitz@redhat.com> In-Reply-To: <20170403160936.28293-1-mreitz@redhat.com> References: <20170403160936.28293-1-mreitz@redhat.com> Subject: [Qemu-devel] [PATCH v2 for-2.10 10/16] block/qcow2: Lock s->lock in preallocate() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: qemu-devel@nongnu.org, Max Reitz , Stefan Hajnoczi , Kevin Wolf preallocate() is and will be called only from places that do not lock s->lock: Currently that is qcow2_create2(), as of a future patch it will be called from qcow2_truncate(), too. It therefore makes sense to move locking that mutex into preallocate() itself. Signed-off-by: Max Reitz Reviewed-by: Stefan Hajnoczi --- block/qcow2.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/block/qcow2.c b/block/qcow2.c index 163d51ec65..f665cd21dc 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -2043,12 +2043,15 @@ static int qcow2_change_backing_file(BlockDriverState *bs, */ static int preallocate(BlockDriverState *bs, int64_t offset, int64_t new_length) { + BDRVQcow2State *s = bs->opaque; uint64_t bytes; uint64_t host_offset = 0; unsigned int cur_bytes; int ret; QCowL2Meta *meta; + qemu_co_mutex_lock(&s->lock); + assert(offset <= new_length); bytes = new_length - offset; @@ -2057,7 +2060,7 @@ static int preallocate(BlockDriverState *bs, int64_t offset, int64_t new_length) ret = qcow2_alloc_cluster_offset(bs, offset, &cur_bytes, &host_offset, &meta); if (ret < 0) { - return ret; + goto done; } while (meta) { @@ -2067,7 +2070,7 @@ static int preallocate(BlockDriverState *bs, int64_t offset, int64_t new_length) if (ret < 0) { qcow2_free_any_clusters(bs, meta->alloc_offset, meta->nb_clusters, QCOW2_DISCARD_NEVER); - return ret; + goto done; } /* There are no dependent requests, but we need to remove our @@ -2094,11 +2097,15 @@ static int preallocate(BlockDriverState *bs, int64_t offset, int64_t new_length) ret = bdrv_pwrite(bs->file, (host_offset + cur_bytes) - 1, &data, 1); if (ret < 0) { - return ret; + goto done; } } - return 0; + ret = 0; + +done: + qemu_co_mutex_unlock(&s->lock); + return ret; } static int qcow2_create2(const char *filename, int64_t total_size, @@ -2318,10 +2325,7 @@ static int qcow2_create2(const char *filename, int64_t total_size, /* And if we're supposed to preallocate metadata, do that now */ if (prealloc != PREALLOC_MODE_OFF) { - BDRVQcow2State *s = blk_bs(blk)->opaque; - qemu_co_mutex_lock(&s->lock); ret = preallocate(blk_bs(blk), 0, total_size); - qemu_co_mutex_unlock(&s->lock); if (ret < 0) { error_setg_errno(errp, -ret, "Could not preallocate metadata"); goto out; -- 2.12.1