From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50583) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e1XdC-000181-Uc for qemu-devel@nongnu.org; Mon, 09 Oct 2017 08:58:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e1XdC-00022E-6H for qemu-devel@nongnu.org; Mon, 09 Oct 2017 08:58:03 -0400 From: Ashijeet Acharya Date: Mon, 9 Oct 2017 18:29:37 +0530 Message-Id: <20171009125940.24220-6-ashijeetacharya@gmail.com> In-Reply-To: <20171009125940.24220-1-ashijeetacharya@gmail.com> References: <20171009125940.24220-1-ashijeetacharya@gmail.com> Subject: [Qemu-devel] [PATCH v9 5/8] vmdk: Set maximum bytes allocated in one cycle List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: famz@redhat.com Cc: kwolf@redhat.com, jsnow@redhat.com, mreitz@redhat.com, stefanha@gmail.com, qemu-devel@nongnu.org, qemu-block@nongnu.org, Ashijeet Acharya Set the maximum bytes allowed to get allocated at once to be not more than the extent size boundary to handle writes at two separate extents appropriately. Signed-off-by: Ashijeet Acharya Reviewed-by: Fam Zheng --- block/vmdk.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/block/vmdk.c b/block/vmdk.c index 07707779a0..11bc0f09c7 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -1641,6 +1641,7 @@ static int vmdk_pwritev(BlockDriverState *bs, uint64_t offset, uint64_t cluster_offset; uint64_t bytes_done = 0; VmdkMetaData m_data; + uint64_t extent_end; if (DIV_ROUND_UP(offset, BDRV_SECTOR_SIZE) > bs->total_sectors) { error_report("Wrong offset: offset=0x%" PRIx64 @@ -1654,9 +1655,17 @@ static int vmdk_pwritev(BlockDriverState *bs, uint64_t offset, if (!extent) { return -EIO; } + extent_end = extent->end_sector * BDRV_SECTOR_SIZE; + offset_in_cluster = vmdk_find_offset_in_cluster(extent, offset); - n_bytes = MIN(bytes, extent->cluster_sectors * BDRV_SECTOR_SIZE - - offset_in_cluster); + + /* truncate n_bytes to first cluster because we need to perform COW */ + if (offset_in_cluster > 0) { + n_bytes = MIN(bytes, extent->cluster_sectors * BDRV_SECTOR_SIZE + - offset_in_cluster); + } else { + n_bytes = MIN(bytes, extent_end - offset); + } ret = vmdk_get_cluster_offset(bs, extent, &m_data, offset, !(extent->compressed || zeroed), -- 2.13.5