From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58457) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WhgEj-0000Pt-84 for qemu-devel@nongnu.org; Tue, 06 May 2014 10:20:55 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WhgEd-0007mL-2o for qemu-devel@nongnu.org; Tue, 06 May 2014 10:20:49 -0400 Received: from mx1.redhat.com ([209.132.183.28]:31370) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WhgEc-0007l3-PT for qemu-devel@nongnu.org; Tue, 06 May 2014 10:20:43 -0400 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s46EKcbh005651 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Tue, 6 May 2014 10:20:41 -0400 From: Kevin Wolf Date: Tue, 6 May 2014 15:30:18 +0200 Message-Id: <1399383018-17797-1-git-send-email-kwolf@redhat.com> Subject: [Qemu-devel] [PATCH] block: Fix bdrv_is_allocated() for short backing files List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, pbonzini@redhat.com, stefanha@redhat.com bdrv_is_allocated() shouldn't return true for sectors that are unallocated, but after the end of a short backing file, even though such sectors are (correctly) marked as containing zeros. Signed-off-by: Kevin Wolf --- block.c | 8 +++++--- include/block/block.h | 11 +++++++---- 2 files changed, 12 insertions(+), 7 deletions(-) diff --git a/block.c b/block.c index c90c71a..d3a9906 100644 --- a/block.c +++ b/block.c @@ -3883,6 +3883,10 @@ static int64_t coroutine_fn bdrv_co_get_block_status(BlockDriverState *bs, *pnum, pnum); } + if (ret & (BDRV_BLOCK_DATA | BDRV_BLOCK_ZERO)) { + ret |= BDRV_BLOCK_ALLOCATED; + } + if (!(ret & BDRV_BLOCK_DATA) && !(ret & BDRV_BLOCK_ZERO)) { if (bdrv_unallocated_blocks_are_zero(bs)) { ret |= BDRV_BLOCK_ZERO; @@ -3959,9 +3963,7 @@ int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, if (ret < 0) { return ret; } - return - (ret & BDRV_BLOCK_DATA) || - ((ret & BDRV_BLOCK_ZERO) && !bdrv_has_zero_init(bs)); + return (ret & BDRV_BLOCK_ALLOCATED); } /* diff --git a/include/block/block.h b/include/block/block.h index 2fda81c..ad4c7e8 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -116,6 +116,8 @@ typedef enum { /* BDRV_BLOCK_DATA: data is read from bs->file or another file * BDRV_BLOCK_ZERO: sectors read as zero * BDRV_BLOCK_OFFSET_VALID: sector stored in bs->file as raw data + * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this + * layer (as opposed to the backing file) * BDRV_BLOCK_RAW: used internally to indicate that the request * was answered by the raw driver and that one * should look in bs->file directly. @@ -137,10 +139,11 @@ typedef enum { * f t f not allocated or unknown offset, read as zero * f f f not allocated or unknown offset, read from backing_hd */ -#define BDRV_BLOCK_DATA 1 -#define BDRV_BLOCK_ZERO 2 -#define BDRV_BLOCK_OFFSET_VALID 4 -#define BDRV_BLOCK_RAW 8 +#define BDRV_BLOCK_DATA 0x01 +#define BDRV_BLOCK_ZERO 0x02 +#define BDRV_BLOCK_OFFSET_VALID 0x04 +#define BDRV_BLOCK_RAW 0x08 +#define BDRV_BLOCK_ALLOCATED 0x10 #define BDRV_BLOCK_OFFSET_MASK BDRV_SECTOR_MASK typedef enum { -- 1.8.3.1