On Tue, 2020-11-17 at 10:26 -0500, J. Bruce Fields wrote: > On Tue, Nov 17, 2020 at 07:34:49AM -0500, Jeff Layton wrote: > > I don't think I described what I was thinking well. Let me try again... > > > > There should be no need to change the code in iversion.h -- I think we > > can do this in a way that's confined to just nfsd/export code. > > > > What I would suggest is to have nfsd4_change_attribute call the > > fetch_iversion op if it exists, instead of checking IS_I_VERSION and > > doing the stuff in that block. If fetch_iversion is NULL, then just use > > the ctime. > > > > Then, you just need to make sure that the filesystems' export_ops have > > an appropriate fetch_iversion vector. xfs, ext4 and btrfs can just call > > inode_query_iversion, and NFS and Ceph can call inode_peek_iversion_raw. > > The rest of the filesystems can leave fetch_iversion as NULL (since we > > don't want to use it on them). > > Thanks for your patience, that makes sense, I'll try it. > There is one gotcha in here though... ext4 needs to also handle the case where SB_I_VERSION is not set. The simple fix might be to just have different export ops for ext4 based on whether it was mounted with -o iversion or not, but maybe there is some better way to do it? -- Jeff Layton <jlayton@xxxxxxxxxx>
