This patch moves L1 table writeout to qcow_disk_flush(). The rationale here is that while writes to clusters that don't have L2 table allocated on-disk are volatile until VIRTIO_BLK_T_FLUSH is issued, we never corrupt the disk image.
Cc: Asias He <[email protected]> Cc: Cyrill Gorcunov <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Prasad Joshi <[email protected]> Cc: Sasha Levin <[email protected]> Signed-off-by: Pekka Enberg <[email protected]> --- tools/kvm/disk/qcow.c | 24 +++++++++++++----------- 1 files changed, 13 insertions(+), 11 deletions(-) diff --git a/tools/kvm/disk/qcow.c b/tools/kvm/disk/qcow.c index 1a6a969..0fef92f 100644 --- a/tools/kvm/disk/qcow.c +++ b/tools/kvm/disk/qcow.c @@ -421,17 +421,6 @@ static ssize_t qcow_write_cluster(struct qcow *q, u64 offset, void *buf, u32 src if (!l2t_off) goto free_cache; - /* Metadata update: update on disk level 1 table */ - t = cpu_to_be64(l2t_off); - - if (qcow_pwrite_sync(q->fd, &t, sizeof(t), header->l1_table_offset + l1t_idx * sizeof(u64)) < 0) { - /* restore file to consistent state */ - if (ftruncate(q->fd, f_sz) < 0) - goto free_cache; - - goto free_cache; - } - if (cache_table(q, l2t) < 0) { if (ftruncate(q->fd, f_sz) < 0) goto free_cache; @@ -522,6 +511,19 @@ static ssize_t qcow_nowrite_sector(struct disk_image *disk, u64 sector, void *sr static int qcow_disk_flush(struct disk_image *disk) { + struct qcow *q = disk->priv; + struct qcow_header *header; + struct qcow_table *table; + + if (fdatasync(disk->fd) < 0) + return -1; + + header = q->header; + table = &q->table; + + if (pwrite_in_full(disk->fd, table->l1_table, table->table_size * sizeof(u64), header->l1_table_offset) < 0) + return -1; + return fsync(disk->fd); } -- 1.7.0.4 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
