diff options
| -rw-r--r-- | qemu-img.c | 22 | ||||
| -rwxr-xr-x | tests/qemu-iotests/251 | 7 |
2 files changed, 27 insertions, 2 deletions
diff --git a/qemu-img.c b/qemu-img.c index d0b1c97562..37365d06fa 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -1666,6 +1666,7 @@ enum ImgConvertBlockStatus { typedef struct ImgConvertState { BlockBackend **src; int64_t *src_sectors; + int *src_alignment; int src_num; int64_t total_sectors; int64_t allocated_sectors; @@ -1732,6 +1733,7 @@ static int convert_iteration_sectors(ImgConvertState *s, int64_t sector_num) if (s->sector_next_status <= sector_num) { uint64_t offset = (sector_num - src_cur_offset) * BDRV_SECTOR_SIZE; int64_t count; + int tail; BlockDriverState *src_bs = blk_bs(s->src[src_cur]); BlockDriverState *base; @@ -1772,6 +1774,16 @@ static int convert_iteration_sectors(ImgConvertState *s, int64_t sector_num) n = DIV_ROUND_UP(count, BDRV_SECTOR_SIZE); + /* + * Avoid that s->sector_next_status becomes unaligned to the source + * request alignment and/or cluster size to avoid unnecessary read + * cycles. + */ + tail = (sector_num - src_cur_offset + n) % s->src_alignment[src_cur]; + if (n > tail) { + n -= tail; + } + if (ret & BDRV_BLOCK_ZERO) { s->status = post_backing_zero ? BLK_BACKING_FILE : BLK_ZERO; } else if (ret & BDRV_BLOCK_DATA) { @@ -2410,8 +2422,10 @@ static int img_convert(int argc, char **argv) s.src = g_new0(BlockBackend *, s.src_num); s.src_sectors = g_new(int64_t, s.src_num); + s.src_alignment = g_new(int, s.src_num); for (bs_i = 0; bs_i < s.src_num; bs_i++) { + BlockDriverState *src_bs; s.src[bs_i] = img_open(image_opts, argv[optind + bs_i], fmt, src_flags, src_writethrough, s.quiet, force_share); @@ -2426,6 +2440,13 @@ static int img_convert(int argc, char **argv) ret = -1; goto out; } + src_bs = blk_bs(s.src[bs_i]); + s.src_alignment[bs_i] = DIV_ROUND_UP(src_bs->bl.request_alignment, + BDRV_SECTOR_SIZE); + if (!bdrv_get_info(src_bs, &bdi)) { + s.src_alignment[bs_i] = MAX(s.src_alignment[bs_i], + bdi.cluster_size / BDRV_SECTOR_SIZE); + } s.total_sectors += s.src_sectors[bs_i]; } @@ -2708,6 +2729,7 @@ out: g_free(s.src); } g_free(s.src_sectors); + g_free(s.src_alignment); fail_getopt: g_free(options); diff --git a/tests/qemu-iotests/251 b/tests/qemu-iotests/251 index 7918ba3559..294773bdc1 100755 --- a/tests/qemu-iotests/251 +++ b/tests/qemu-iotests/251 @@ -46,8 +46,11 @@ if [ "$IMGOPTSSYNTAX" = "true" ]; then # We use json:{} filenames here, so we cannot work with additional options. _unsupported_fmt $IMGFMT else - # With VDI, the output is ordered differently. Just disable it. - _unsupported_fmt vdi + # - With VDI, the output is ordered differently. Just disable it. + # - VHDX has large clusters; because qemu-img convert tries to + # align the requests to the cluster size, the output is ordered + # differently, so disable it, too. + _unsupported_fmt vdi vhdx fi |