Re: [PATCH 24/24] fs: remove simple_nosetlease()

[Jeff Layton <jlayton@kernel.org>]

On Wed, 2026-02-25 at 12:58 -0500, Mike Snitzer wrote:
> On Thu, Jan 08, 2026 at 12:13:19PM -0500, Jeff Layton wrote:
> > Setting ->setlease() to a NULL pointer now has the same effect as
> > setting it to simple_nosetlease(). Remove all of the setlease
> > file_operations that are set to simple_nosetlease, and the function
> > itself.
> > 
> > Signed-off-by: Jeff Layton <jlayton@kernel.org>
> > ---
> >  fs/9p/vfs_dir.c        |  2 --
> >  fs/9p/vfs_file.c       |  2 --
> >  fs/ceph/dir.c          |  2 --
> >  fs/ceph/file.c         |  1 -
> >  fs/fuse/dir.c          |  1 -
> >  fs/gfs2/file.c         |  2 --
> >  fs/libfs.c             | 18 ------------------
> >  fs/nfs/dir.c           |  1 -
> >  fs/nfs/file.c          |  1 -
> >  fs/smb/client/cifsfs.c |  1 -
> >  fs/vboxsf/dir.c        |  1 -
> >  fs/vboxsf/file.c       |  1 -
> >  include/linux/fs.h     |  1 -
> >  13 files changed, 34 deletions(-)
> > 
> 
> <snip>
> 
> > diff --git a/fs/libfs.c b/fs/libfs.c
> > index 697c6d5fc12786c036f0086886297fb5cd52ae00..f1860dff86f2703266beecf31e9d2667af7a9684 100644
> > --- a/fs/libfs.c
> > +++ b/fs/libfs.c
> > @@ -1699,24 +1699,6 @@ struct inode *alloc_anon_inode(struct super_block *s)
> >  }
> >  EXPORT_SYMBOL(alloc_anon_inode);
> >  
> > -/**
> > - * simple_nosetlease - generic helper for prohibiting leases
> > - * @filp: file pointer
> > - * @arg: type of lease to obtain
> > - * @flp: new lease supplied for insertion
> > - * @priv: private data for lm_setup operation
> > - *
> > - * Generic helper for filesystems that do not wish to allow leases to be set.
> > - * All arguments are ignored and it just returns -EINVAL.
> > - */
> > -int
> > -simple_nosetlease(struct file *filp, int arg, struct file_lease **flp,
> > -		  void **priv)
> > -{
> > -	return -EINVAL;
> > -}
> > -EXPORT_SYMBOL(simple_nosetlease);
> > -
> >  /**
> >   * simple_get_link - generic helper to get the target of "fast" symlinks
> >   * @dentry: not used here
> > diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
> > index 71df279febf797880ded19e45528c3df4cea2dde..23a78a742b619dea8b76ddf28f4f59a1c8a015e2 100644
> > --- a/fs/nfs/dir.c
> > +++ b/fs/nfs/dir.c
> > @@ -66,7 +66,6 @@ const struct file_operations nfs_dir_operations = {
> >  	.open		= nfs_opendir,
> >  	.release	= nfs_closedir,
> >  	.fsync		= nfs_fsync_dir,
> > -	.setlease	= simple_nosetlease,
> >  };
> >  
> >  const struct address_space_operations nfs_dir_aops = {
> > diff --git a/fs/nfs/file.c b/fs/nfs/file.c
> > index d020aab40c64ebda30d130b6acee1b9194621457..9d269561961825f88529551b0f0287920960ac62 100644
> > --- a/fs/nfs/file.c
> > +++ b/fs/nfs/file.c
> > @@ -962,7 +962,6 @@ const struct file_operations nfs_file_operations = {
> >  	.splice_read	= nfs_file_splice_read,
> >  	.splice_write	= iter_file_splice_write,
> >  	.check_flags	= nfs_check_flags,
> > -	.setlease	= simple_nosetlease,
> >  	.fop_flags	= FOP_DONTCACHE,
> >  };
> >  EXPORT_SYMBOL_GPL(nfs_file_operations);
> 
> Hey Jeff,
> 
> I've noticed an NFS reexport regression in v6.19 and now v7.0-rc1
> (similar but different due to your series that requires opt-in via
> .setlease).
> 
> Bisect first pointed out this commit:
> 10dcd5110678 nfs: properly disallow delegation requests on directories
> 
> And now with v7.0-rc1 its the fact that NFS doesn't provide .setlease
> so lstat() on parent dir (of file that I touch) gets -EINVAL.
> 
> So its a confluence of NFS's dir delegations and your setlease changes.
> 
> If I reexport NFSv4.2 filesystem in terms of NFSv4.1, the regression
> is seen by doing (lstat reproducer that gemini spit out for me is
> attached):
> 
> $ touch /mnt/share41/test
> $ strace ./lstat /mnt/share41
> ...
> lstat("/mnt/share41", 0x7ffec0d79920)   = -1 EINVAL (Invalid argument)
> 
> If I immediately re-run it works:
> ...
> lstat("/mnt/share41", {st_mode=S_IFDIR|0777, st_size=4096, ...}) = 0
> 
> I'm not sure what the proper fix is yet, but I feel like you've missed
> that NFS itself can be (re)exported?
> 
> 

My apologies. I missed seeing this last week.

That's a very simple reproducer! That's very strange behavior,
especially since NFS4 does provide a setlease operation:

const struct file_operations nfs4_file_operations = {
	[...]
	.setlease       = nfs4_setlease,
	[...]
};

I'm not sure why this would cause lstat() to return -EINVAL. What's
happening on the wire when this occurs?

I'll plan to take a look here soon either way.
-- 
Jeff Layton <jlayton@kernel.org>