From f10cc24359917da1347c0a56a2cbda3a5fcf9ce6 Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Mon, 25 Apr 2016 17:34:41 +0200 Subject: [PATCH] vmdk: Implement .bdrv_co_preadv() interface Signed-off-by: Kevin Wolf Reviewed-by: Fam Zheng --- block/vmdk.c | 98 ++++++++++++++++++++++++++++------------------------ 1 file changed, 53 insertions(+), 45 deletions(-) diff --git a/block/vmdk.c b/block/vmdk.c index f1e01f9731..6c447add3a 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -1381,8 +1381,8 @@ static int vmdk_write_extent(VmdkExtent *extent, int64_t cluster_offset, } static int vmdk_read_extent(VmdkExtent *extent, int64_t cluster_offset, - int64_t offset_in_cluster, uint8_t *buf, - int nb_sectors) + int64_t offset_in_cluster, QEMUIOVector *qiov, + int bytes) { int ret; int cluster_bytes, buf_bytes; @@ -1394,14 +1394,13 @@ static int vmdk_read_extent(VmdkExtent *extent, int64_t cluster_offset, if (!extent->compressed) { - ret = bdrv_pread(extent->file->bs, - cluster_offset + offset_in_cluster, - buf, nb_sectors * 512); - if (ret == nb_sectors * 512) { - return 0; - } else { - return -EIO; + ret = bdrv_co_preadv(extent->file->bs, + cluster_offset + offset_in_cluster, bytes, + qiov, 0); + if (ret < 0) { + return ret; } + return 0; } cluster_bytes = extent->cluster_sectors * 512; /* Read two clusters in case GrainMarker + compressed data > one cluster */ @@ -1433,11 +1432,11 @@ static int vmdk_read_extent(VmdkExtent *extent, int64_t cluster_offset, } if (offset_in_cluster < 0 || - offset_in_cluster + nb_sectors * 512 > buf_len) { + offset_in_cluster + bytes > buf_len) { ret = -EINVAL; goto out; } - memcpy(buf, uncomp_buf + offset_in_cluster, nb_sectors * 512); + qemu_iovec_from_buf(qiov, 0, uncomp_buf + offset_in_cluster, bytes); ret = 0; out: @@ -1446,64 +1445,73 @@ static int vmdk_read_extent(VmdkExtent *extent, int64_t cluster_offset, return ret; } -static int vmdk_read(BlockDriverState *bs, int64_t sector_num, - uint8_t *buf, int nb_sectors) +static int coroutine_fn +vmdk_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes, + QEMUIOVector *qiov, int flags) { BDRVVmdkState *s = bs->opaque; int ret; - uint64_t n, index_in_cluster; + uint64_t n_bytes, offset_in_cluster; VmdkExtent *extent = NULL; + QEMUIOVector local_qiov; uint64_t cluster_offset; + uint64_t bytes_done = 0; - while (nb_sectors > 0) { - extent = find_extent(s, sector_num, extent); + qemu_iovec_init(&local_qiov, qiov->niov); + qemu_co_mutex_lock(&s->lock); + + while (bytes > 0) { + extent = find_extent(s, offset >> BDRV_SECTOR_BITS, extent); if (!extent) { - return -EIO; + ret = -EIO; + goto fail; } ret = get_cluster_offset(bs, extent, NULL, - sector_num << 9, false, &cluster_offset, - 0, 0); - index_in_cluster = vmdk_find_index_in_cluster(extent, sector_num); - n = extent->cluster_sectors - index_in_cluster; - if (n > nb_sectors) { - n = nb_sectors; - } + offset, false, &cluster_offset, 0, 0); + offset_in_cluster = vmdk_find_offset_in_cluster(extent, offset); + + n_bytes = MIN(bytes, extent->cluster_sectors * BDRV_SECTOR_SIZE + - offset_in_cluster); + if (ret != VMDK_OK) { /* if not allocated, try to read from parent image, if exist */ if (bs->backing && ret != VMDK_ZEROED) { if (!vmdk_is_cid_valid(bs)) { - return -EINVAL; + ret = -EINVAL; + goto fail; } - ret = bdrv_read(bs->backing->bs, sector_num, buf, n); + + qemu_iovec_reset(&local_qiov); + qemu_iovec_concat(&local_qiov, qiov, bytes_done, n_bytes); + + ret = bdrv_co_preadv(bs->backing->bs, offset, n_bytes, + &local_qiov, 0); if (ret < 0) { - return ret; + goto fail; } } else { - memset(buf, 0, 512 * n); + qemu_iovec_memset(qiov, bytes_done, 0, n_bytes); } } else { - ret = vmdk_read_extent(extent, - cluster_offset, index_in_cluster * 512, - buf, n); + qemu_iovec_reset(&local_qiov); + qemu_iovec_concat(&local_qiov, qiov, bytes_done, n_bytes); + + ret = vmdk_read_extent(extent, cluster_offset, offset_in_cluster, + &local_qiov, n_bytes); if (ret) { - return ret; + goto fail; } } - nb_sectors -= n; - sector_num += n; - buf += n * 512; + bytes -= n_bytes; + offset += n_bytes; + bytes_done += n_bytes; } - return 0; -} -static coroutine_fn int vmdk_co_read(BlockDriverState *bs, int64_t sector_num, - uint8_t *buf, int nb_sectors) -{ - int ret; - BDRVVmdkState *s = bs->opaque; - qemu_co_mutex_lock(&s->lock); - ret = vmdk_read(bs, sector_num, buf, nb_sectors); + ret = 0; +fail: qemu_co_mutex_unlock(&s->lock); + qemu_iovec_destroy(&local_qiov); + return ret; } @@ -2332,7 +2340,7 @@ static BlockDriver bdrv_vmdk = { .bdrv_open = vmdk_open, .bdrv_check = vmdk_check, .bdrv_reopen_prepare = vmdk_reopen_prepare, - .bdrv_read = vmdk_co_read, + .bdrv_co_preadv = vmdk_co_preadv, .bdrv_write = vmdk_co_write, .bdrv_write_compressed = vmdk_write_compressed, .bdrv_co_write_zeroes = vmdk_co_write_zeroes,