diff options
| -rw-r--r-- | block/qcow2-cluster.c | 27 |
1 files changed, 19 insertions, 8 deletions
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 0e337075b3..07a2e936fd 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -289,12 +289,15 @@ void qcow2_encrypt_sectors(BDRVQcowState *s, int64_t sector_num, } } -static int copy_sectors(BlockDriverState *bs, uint64_t start_sect, - uint64_t cluster_offset, int n_start, int n_end) +static int coroutine_fn copy_sectors(BlockDriverState *bs, + uint64_t start_sect, + uint64_t cluster_offset, + int n_start, int n_end) { BDRVQcowState *s = bs->opaque; + QEMUIOVector qiov; + struct iovec iov; int n, ret; - void *buf; /* * If this is the last cluster and it is only partially used, we must only @@ -310,29 +313,37 @@ static int copy_sectors(BlockDriverState *bs, uint64_t start_sect, return 0; } - buf = qemu_blockalign(bs, n * BDRV_SECTOR_SIZE); + iov.iov_len = n * BDRV_SECTOR_SIZE; + iov.iov_base = qemu_blockalign(bs, iov.iov_len); + + qemu_iovec_init_external(&qiov, &iov, 1); BLKDBG_EVENT(bs->file, BLKDBG_COW_READ); - ret = bdrv_read(bs, start_sect + n_start, buf, n); + + /* Call .bdrv_co_readv() directly instead of using the public block-layer + * interface. This avoids double I/O throttling and request tracking, + * which can lead to deadlock when block layer copy-on-read is enabled. + */ + ret = bs->drv->bdrv_co_readv(bs, start_sect + n_start, n, &qiov); if (ret < 0) { goto out; } if (s->crypt_method) { qcow2_encrypt_sectors(s, start_sect + n_start, - buf, buf, n, 1, + iov.iov_base, iov.iov_base, n, 1, &s->aes_encrypt_key); } BLKDBG_EVENT(bs->file, BLKDBG_COW_WRITE); - ret = bdrv_write(bs->file, (cluster_offset >> 9) + n_start, buf, n); + ret = bdrv_co_writev(bs->file, (cluster_offset >> 9) + n_start, n, &qiov); if (ret < 0) { goto out; } ret = 0; out: - qemu_vfree(buf); + qemu_vfree(iov.iov_base); return ret; } |