On Wed, 2021-04-07 at 18:08 -0700, Eric Biggers wrote: > On Fri, Mar 26, 2021 at 01:32:09PM -0400, Jeff Layton wrote: > > Ceph needs to be able to allocate inodes ahead of a create that might > > involve a fscrypt-encrypted inode. new_inode() almost fits the bill, > > but it puts the inode on the sb->s_inodes list and when we go to hash > > it, that might be done again. > > > > We could work around that by setting I_CREATING on the new inode, but > > that causes ilookup5 to return -ESTALE if something tries to find it > > before I_NEW is cleared. To work around all of this, just use > > new_inode_pseudo which doesn't add it to the list. > > > > Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> > > Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx> > > IIRC, this looked like a bug in ilookup5(). Did you come to the conclusion that > it's not actually a bug? > Yes. Al pointed out that it's desirable behavior for most (simpler) filesystems. Basically, nothing should have presented the filehandle for this inode to a client until after I_NEW has been cleared. So, any attempt to look it up should give you back ESTALE at this point. I'm not married to this approach however. If there's a better way to do this, then I'm happy to consider it. -- Jeff Layton <jlayton@xxxxxxxxxx>
