From 4237964a9f433faaf643166a8ce9c070dc4cf165 Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Thu, 14 Jan 2016 15:10:31 +0100 Subject: [PATCH] raw-posix: Fix .bdrv_co_get_block_status() for unaligned image size Message-id: <1452784231-14211-2-git-send-email-mreitz@redhat.com> Patchwork-id: 68756 O-Subject: [RHEL-7.3 qemu-kvm PATCH 1/1] raw-posix: Fix .bdrv_co_get_block_status() for unaligned image size Bugzilla: 1283116 RH-Acked-by: Fam Zheng RH-Acked-by: Stefan Hajnoczi RH-Acked-by: Kevin Wolf From: Kevin Wolf Image files with an unaligned image size have a final hole that starts at EOF, i.e. in the middle of a sector. Currently, *pnum == 0 is returned when checking the status of this sector. In qemu-img, this triggers an assertion failure. In order to fix this, one type for the sector that contains EOF must be found. Treating a hole as data is safe, so this patch rounds the calculated number of data sectors up, so that a partial sector at EOF is treated as a full data sector. This fixes https://bugzilla.redhat.com/show_bug.cgi?id=1229394 Signed-off-by: Kevin Wolf Reviewed-by: Eric Blake Tested-by: Cole Robinson (cherry picked from commit b8684454e152ca2e100f4b59d80de2be27186206) Signed-off-by: Max Reitz Signed-off-by: Miroslav Rezanina --- block/raw-posix.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/block/raw-posix.c b/block/raw-posix.c index 72a9dc0..1f5275f 100644 --- a/block/raw-posix.c +++ b/block/raw-posix.c @@ -1452,8 +1452,9 @@ static int64_t coroutine_fn raw_co_get_block_status(BlockDriverState *bs, *pnum = nb_sectors; ret = BDRV_BLOCK_DATA; } else if (data == start) { - /* On a data extent, compute sectors to the end of the extent. */ - *pnum = MIN(nb_sectors, (hole - start) / BDRV_SECTOR_SIZE); + /* On a data extent, compute sectors to the end of the extent, + * possibly including a partial sector at EOF. */ + *pnum = MIN(nb_sectors, DIV_ROUND_UP(hole - start, BDRV_SECTOR_SIZE)); ret = BDRV_BLOCK_DATA; } else { /* On a hole, compute sectors to the beginning of the next extent. */ -- 1.8.3.1