On Wed, Jan 08, 2014 at 11:09:02PM +0800, Wang Shilong wrote: > > Hello David, > > > On Tue, Jan 07, 2014 at 05:25:18PM +0800, Wang Shilong wrote: > >> Steps to reproduce: > >> # mkfs.btrfs -f /dev/sda8 > >> # mount /dev/sda8 /mnt > >> # btrfs sub snapshot -r /mnt /mnt/snap1 > >> # btrfs sub snapshot -r /mnt /mnt/snap2 > >> # btrfs send /mnt/snap1 -p /mnt/snap2 -f /mnt/1 > >> # dmesg > >> > >> The problem is that we will sort clone roots(include @send_root), it > >> might push @send_root before thus @send_root's @send_in_progress will > >> be decreased twice. > > > > Of course, the sort(). I think your fix adds some complexity that's not > > necessary. Whether the clone_roots array is sorted is not important, we > > just have to process each root once. > > > > send_root becomes a clone_root member, so the missing part is to account > > in the rollback counter: > > > > --- a/fs/btrfs/send.c > > +++ b/fs/btrfs/send.c > > @@ -4937,6 +4937,7 @@ long btrfs_ioctl_send(struct file *mnt_file, void > > __user *arg_) > > * for possible clone sources. > > */ > > sctx->clone_roots[sctx->clone_roots_cnt++].root = sctx->send_root; > > + clone_sources_to_rollback++; > > Not really, If we fail to come here, we still need decrease @send_root.
Right. I was thinking if the code can be simplified somehow, but don't have anything vastly better. Can you please add a comment to the first branch that send_root is processed in the loop and not missed? It looks unabalanced when it's handled just a few lines below and not in the 1st loop. thanks, david -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
