From patchwork Wed Oct 10 05:56:36 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [2/2] block: in commit, determine base image from the top image Date: Tue, 09 Oct 2012 19:56:36 -0000 From: Jeff Cody X-Patchwork-Id: 190549 Message-Id: <633f30c7b1812692ca9cd4497f502d5a7366e7e3.1349848348.git.jcody@redhat.com> To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, pbonzini@redhat.com This simplifies some code and error checking, and also fixes a bug. bdrv_find_backing_image() should only be passed absolute filenames, or filenames relative to the chain. In the QMP message handler for block commit, when looking up the base do so from the determined top image, so we know it is reachable from top. Signed-off-by: Jeff Cody Reviewed-by: Paolo Bonzini Reviewed-by: Eric Blake --- block/commit.c | 9 --------- blockdev.c | 21 +++++++++++---------- 2 files changed, 11 insertions(+), 19 deletions(-) diff --git a/block/commit.c b/block/commit.c index 733c914..13d9e82 100644 --- a/block/commit.c +++ b/block/commit.c @@ -211,15 +211,6 @@ void commit_start(BlockDriverState *bs, BlockDriverState *base, return; } - /* top and base may be valid, but let's make sure that base is reachable - * from top */ - if (bdrv_find_backing_image(top, base->filename) != base) { - error_setg(errp, - "Base (%s) is not reachable from top (%s)", - base->filename, top->filename); - return; - } - overlay_bs = bdrv_find_overlay(bs, top); if (overlay_bs == NULL) { diff --git a/blockdev.c b/blockdev.c index 99828ad..7052287 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1157,16 +1157,6 @@ void qmp_block_commit(const char *device, error_set(errp, QERR_DEVICE_NOT_FOUND, device); return; } - if (base && has_base) { - base_bs = bdrv_find_backing_image(bs, base); - } else { - base_bs = bdrv_find_base(bs); - } - - if (base_bs == NULL) { - error_set(errp, QERR_BASE_NOT_FOUND, base ? base : "NULL"); - return; - } /* default top_bs is the active layer */ top_bs = bs; @@ -1182,6 +1172,17 @@ void qmp_block_commit(const char *device, return; } + if (base && has_base) { + base_bs = bdrv_find_backing_image(top_bs, base); + } else { + base_bs = bdrv_find_base(top_bs); + } + + if (base_bs == NULL) { + error_set(errp, QERR_BASE_NOT_FOUND, base ? base : "NULL"); + return; + } + commit_start(bs, base_bs, top_bs, speed, on_error, block_job_cb, bs, &local_err); if (local_err != NULL) {