On Fri, Mar 30, 2018 at 01:53:24PM +0300, Amir Goldstein wrote: > On Thu, Mar 29, 2018 at 10:38 PM, Vivek Goyal <vgoyal@xxxxxxxxxx> wrote: > > If we find a upper metacopy inode, make sure we also found associated data > > dentry in lower. Otherwise copy up operation later will fail. > > > > There are two cases where this can happen. First case is that somehow > > data file was removed from lower layer. Other case is that REDIRECT > > xattr was removed due to copy up of file on another cpu (when inode is > > shared between two dentries) and hence ovl_lookup() could not find the > > correct dentry. > > > > Remind me again why we remove REDIRECT xattr? > Is it a must for functionality or just for being boy scouts? > I would prefer to avoid having to deal with races of this sort. > You can cleanup REDIRECT for non-dir that is not metacopy > on lookup when finding a I_NEW inode. Ok, thinking more about it. If we were to clean REDIRECT on lookup when finding I_NEW inode, that means we will have to always do vfs_removexattr(OVL_XATTR_REDIRECT) on all non-metacopy non-dir files. That does not sound like a very good idea. Its unnecessary overhead in lookup path. IOW, I think removing REDIRECT and doing appropriate locking around ovl_inode->redirect is probably better. Thanks Vivek -- To unsubscribe from this list: send the line "unsubscribe linux-unionfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
