diff options
| -rw-r--r-- | block/qcow2-cluster.c | 104 |
1 files changed, 35 insertions, 69 deletions
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index f4e049fa90..0e337075b3 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -289,89 +289,51 @@ void qcow2_encrypt_sectors(BDRVQcowState *s, int64_t sector_num, } } - -static int qcow2_read(BlockDriverState *bs, int64_t sector_num, - uint8_t *buf, int nb_sectors) -{ - BDRVQcowState *s = bs->opaque; - int ret, index_in_cluster, n, n1; - uint64_t cluster_offset; - struct iovec iov; - QEMUIOVector qiov; - - while (nb_sectors > 0) { - n = nb_sectors; - - ret = qcow2_get_cluster_offset(bs, sector_num << 9, &n, - &cluster_offset); - if (ret < 0) { - return ret; - } - - index_in_cluster = sector_num & (s->cluster_sectors - 1); - if (!cluster_offset) { - if (bs->backing_hd) { - /* read from the base image */ - iov.iov_base = buf; - iov.iov_len = n * 512; - qemu_iovec_init_external(&qiov, &iov, 1); - - n1 = qcow2_backing_read1(bs->backing_hd, &qiov, sector_num, n); - if (n1 > 0) { - BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING); - ret = bdrv_read(bs->backing_hd, sector_num, buf, n1); - if (ret < 0) - return -1; - } - } else { - memset(buf, 0, 512 * n); - } - } else if (cluster_offset & QCOW_OFLAG_COMPRESSED) { - if (qcow2_decompress_cluster(bs, cluster_offset) < 0) - return -1; - memcpy(buf, s->cluster_cache + index_in_cluster * 512, 512 * n); - } else { - BLKDBG_EVENT(bs->file, BLKDBG_READ); - ret = bdrv_pread(bs->file, cluster_offset + index_in_cluster * 512, buf, n * 512); - if (ret != n * 512) - return -1; - if (s->crypt_method) { - qcow2_encrypt_sectors(s, sector_num, buf, buf, n, 0, - &s->aes_decrypt_key); - } - } - nb_sectors -= n; - sector_num += n; - buf += n * 512; - } - return 0; -} - static int copy_sectors(BlockDriverState *bs, uint64_t start_sect, uint64_t cluster_offset, int n_start, int n_end) { BDRVQcowState *s = bs->opaque; int n, ret; + void *buf; + + /* + * If this is the last cluster and it is only partially used, we must only + * copy until the end of the image, or bdrv_check_request will fail for the + * bdrv_read/write calls below. + */ + if (start_sect + n_end > bs->total_sectors) { + n_end = bs->total_sectors - start_sect; + } n = n_end - n_start; - if (n <= 0) + if (n <= 0) { return 0; + } + + buf = qemu_blockalign(bs, n * BDRV_SECTOR_SIZE); + BLKDBG_EVENT(bs->file, BLKDBG_COW_READ); - ret = qcow2_read(bs, start_sect + n_start, s->cluster_data, n); - if (ret < 0) - return ret; + ret = bdrv_read(bs, start_sect + n_start, buf, n); + if (ret < 0) { + goto out; + } + if (s->crypt_method) { qcow2_encrypt_sectors(s, start_sect + n_start, - s->cluster_data, - s->cluster_data, n, 1, + buf, buf, n, 1, &s->aes_encrypt_key); } + BLKDBG_EVENT(bs->file, BLKDBG_COW_WRITE); - ret = bdrv_write(bs->file, (cluster_offset >> 9) + n_start, - s->cluster_data, n); - if (ret < 0) - return ret; - return 0; + ret = bdrv_write(bs->file, (cluster_offset >> 9) + n_start, buf, n); + if (ret < 0) { + goto out; + } + + ret = 0; +out: + qemu_vfree(buf); + return ret; } @@ -620,7 +582,9 @@ int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m) start_sect = (m->offset & ~(s->cluster_size - 1)) >> 9; if (m->n_start) { cow = true; + qemu_co_mutex_unlock(&s->lock); ret = copy_sectors(bs, start_sect, cluster_offset, 0, m->n_start); + qemu_co_mutex_lock(&s->lock); if (ret < 0) goto err; } @@ -628,8 +592,10 @@ int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m) if (m->nb_available & (s->cluster_sectors - 1)) { uint64_t end = m->nb_available & ~(uint64_t)(s->cluster_sectors - 1); cow = true; + qemu_co_mutex_unlock(&s->lock); ret = copy_sectors(bs, start_sect + end, cluster_offset + (end << 9), m->nb_available - end, s->cluster_sectors); + qemu_co_mutex_lock(&s->lock); if (ret < 0) goto err; } |