From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42381) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dGPw3-00076v-I8 for qemu-devel@nongnu.org; Thu, 01 Jun 2017 09:14:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dGPw2-0002AU-IR for qemu-devel@nongnu.org; Thu, 01 Jun 2017 09:14:43 -0400 Date: Thu, 1 Jun 2017 21:14:32 +0800 From: Fam Zheng Message-ID: <20170601131432.GF13127@lemon.lan> References: <1492838021-10538-1-git-send-email-ashijeetacharya@gmail.com> <1492838021-10538-6-git-send-email-ashijeetacharya@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1492838021-10538-6-git-send-email-ashijeetacharya@gmail.com> Subject: Re: [Qemu-devel] [PATCH v4 5/8] vmdk: Set maximum bytes allocated in one cycle List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Ashijeet Acharya Cc: kwolf@redhat.com, jsnow@redhat.com, mreitz@redhat.com, stefanha@gmail.com, qemu-devel@nongnu.org, qemu-block@nongnu.org On Sat, 04/22 10:43, Ashijeet Acharya wrote: > 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 > --- > block/vmdk.c | 13 +++++++++++-- > 1 file changed, 11 insertions(+), 2 deletions(-) > > diff --git a/block/vmdk.c b/block/vmdk.c > index 4cee868..7862791 100644 > --- a/block/vmdk.c > +++ b/block/vmdk.c > @@ -1624,6 +1624,7 @@ 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 > @@ -1637,9 +1638,17 @@ 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), > -- > 2.6.2 > Reviewed-by: Fam Zheng