From: Kevin Wolf Date: Tue, 1 Jul 2014 14:52:21 +0000 (+0200) Subject: mirror: Fix qiov size for short requests X-Git-Tag: qemu-xen-4.5.0-rc1^2~4 X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=3c548f670060ffa835fdf26a67d0a7de926ca8c8;p=qemu-xen.git mirror: Fix qiov size for short requests When mirroring an image of a size that is not a multiple of the mirror job granularity, the last request would have the right nb_sectors argument, but a qiov that is rounded up to the next multiple of the granularity. Don't do this. This fixes a segfault that is caused by raw-posix being confused by this and allocating a buffer with request length, but operating on it with qiov length. [s/Driver/Drive/ in qemu-iotests 041 as suggested by Eric --Stefan] Reported-by: Eric Blake Signed-off-by: Kevin Wolf Tested-by: Eric Blake Reviewed-by: Eric Blake Signed-off-by: Stefan Hajnoczi (cherry picked from commit 5a0f6fd5c84573387056e0464a7fc0c6fb70b2dc) Conflicts: tests/qemu-iotests/041.out *updated 041.out to reflect tests missing from 2.0 Signed-off-by: Michael Roth --- diff --git a/block/mirror.c b/block/mirror.c index 21f2d8dcfd..6e502e3f21 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -259,9 +259,11 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s) next_sector = sector_num; while (nb_chunks-- > 0) { MirrorBuffer *buf = QSIMPLEQ_FIRST(&s->buf_free); + size_t remaining = (nb_sectors * BDRV_SECTOR_SIZE) - op->qiov.size; + QSIMPLEQ_REMOVE_HEAD(&s->buf_free, next); s->buf_free_count--; - qemu_iovec_add(&op->qiov, buf, s->granularity); + qemu_iovec_add(&op->qiov, buf, MIN(s->granularity, remaining)); /* Advance the HBitmapIter in parallel, so that we do not examine * the same sector twice. diff --git a/tests/qemu-iotests/041 b/tests/qemu-iotests/041 index ef4f4657cc..ef74be63ec 100755 --- a/tests/qemu-iotests/041 +++ b/tests/qemu-iotests/041 @@ -211,6 +211,11 @@ class TestSingleDriveZeroLength(TestSingleDrive): test_small_buffer2 = None test_large_cluster = None +class TestSingleDriveUnalignedLength(TestSingleDrive): + image_len = 1025 * 1024 + test_small_buffer2 = None + test_large_cluster = None + class TestMirrorNoBacking(ImageMirroringTestCase): image_len = 2 * 1024 * 1024 # MB diff --git a/tests/qemu-iotests/041.out b/tests/qemu-iotests/041.out index cfa5c0d0e6..802ffaa0c0 100644 --- a/tests/qemu-iotests/041.out +++ b/tests/qemu-iotests/041.out @@ -1,5 +1,5 @@ -................................... +........................................... ---------------------------------------------------------------------- -Ran 35 tests +Ran 43 tests OK