From 70023da276ed7a46201e7b0d3168b005ad82fecb Mon Sep 17 00:00:00 2001 From: Stefan Behrens Date: Wed, 17 Apr 2013 09:11:47 +0000 Subject: [PATCH] Btrfs: clear received_uuid field for new writable snapshots For created snapshots, the full root_item is copied from the source root and afterwards selectively modified. The current code forgets to clear the field received_uuid. The only problem is that it is confusing when you look at it with 'btrfs subv list', since for writable snapshots, the contents of the snapshot can be completely unrelated to the previously received snapshot. The receiver ignores such snapshots anyway because he also checks the field stransid in the root_item and that value used to be reset to zero for all created snapshots. This commit changes two things: - clear the received_uuid field for new writable snapshots. - don't clear the send/receive related information like the stransid for read-only snapshots (which makes them useable as a parent for the automatic selection of parents in the receive code). Signed-off-by: Stefan Behrens Signed-off-by: Josef Bacik --- fs/btrfs/transaction.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index de774580134f..258fcebc7ccf 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -1169,13 +1169,17 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, memcpy(new_root_item->uuid, new_uuid.b, BTRFS_UUID_SIZE); memcpy(new_root_item->parent_uuid, root->root_item.uuid, BTRFS_UUID_SIZE); + if (!(root_flags & BTRFS_ROOT_SUBVOL_RDONLY)) { + memset(new_root_item->received_uuid, 0, + sizeof(new_root_item->received_uuid)); + memset(&new_root_item->stime, 0, sizeof(new_root_item->stime)); + memset(&new_root_item->rtime, 0, sizeof(new_root_item->rtime)); + btrfs_set_root_stransid(new_root_item, 0); + btrfs_set_root_rtransid(new_root_item, 0); + } new_root_item->otime.sec = cpu_to_le64(cur_time.tv_sec); new_root_item->otime.nsec = cpu_to_le32(cur_time.tv_nsec); btrfs_set_root_otransid(new_root_item, trans->transid); - memset(&new_root_item->stime, 0, sizeof(new_root_item->stime)); - memset(&new_root_item->rtime, 0, sizeof(new_root_item->rtime)); - btrfs_set_root_stransid(new_root_item, 0); - btrfs_set_root_rtransid(new_root_item, 0); old = btrfs_lock_root_node(root); ret = btrfs_cow_block(trans, root, old, NULL, 0, &old); -- 2.20.1