Commit 9f1b92ad authored by Vladimir Sementsov-Ogievskiy's avatar Vladimir Sementsov-Ogievskiy Committed by Max Reitz
Browse files

qemu-img: improve convert_iteration_sectors() 



Do not do extra call to _get_block_status()

Signed-off-by: default avatarVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20170407113404.9351-1-vsementsov@virtuozzo.com
Reviewed-by: default avatarJohn Snow <jsnow@redhat.com>
Signed-off-by: default avatarMax Reitz <mreitz@redhat.com>
parent 504c205a

qemu-img.c

+10 −22
Original line number Diff line number Diff line
@@ -1554,37 +1554,25 @@ static int convert_iteration_sectors(ImgConvertState *s, int64_t sector_num) 


    if (s->sector_next_status <= sector_num) {

        BlockDriverState *file;

        if (s->target_has_backing) {

            ret = bdrv_get_block_status(blk_bs(s->src[src_cur]),

                                        sector_num - src_cur_offset,

                                        n, &n, &file);

        if (ret < 0) {

            return ret;

        }



        if (ret & BDRV_BLOCK_ZERO) {

            s->status = BLK_ZERO;

        } else if (ret & BDRV_BLOCK_DATA) {

            s->status = BLK_DATA;

        } else if (!s->target_has_backing) {

            /* Without a target backing file we must copy over the contents of

             * the backing file as well. */

            /* Check block status of the backing file chain to avoid

             * needlessly reading zeroes and limiting the iteration to the

             * buffer size */

        } else {

            ret = bdrv_get_block_status_above(blk_bs(s->src[src_cur]), NULL,

                                              sector_num - src_cur_offset,

                                              n, &n, &file);

        }

        if (ret < 0) {

            return ret;

        }



        if (ret & BDRV_BLOCK_ZERO) {

            s->status = BLK_ZERO;

            } else {

        } else if (ret & BDRV_BLOCK_DATA) {

            s->status = BLK_DATA;

            }

        } else {

            s->status = BLK_BACKING_FILE;

            s->status = s->target_has_backing ? BLK_BACKING_FILE : BLK_DATA;

        }



        s->sector_next_status = sector_num + n;