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

[Mike Snitzer <snitzer@kernel.org>]

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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?

Thanks,
Mike

[-- Attachment #2: lstat.c --]
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#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>

int main(int argc, char *argv[]) {
    // 1. Check if the filename was provided via argv
    if (argc < 2) {
        fprintf(stderr, "Usage: %s <filename>\n", argv[0]);
        return EXIT_FAILURE;
    }

    struct stat file_stats;

    // 2. Pass the filename to the lstat syscall
    if (lstat(argv[1], &file_stats) < 0) {
        perror("lstat error");
        return EXIT_FAILURE;
    }

    // 3. Display some basic metadata
    printf("Information for: %s\n", argv[1]);
    printf("---------------------------\n");
    printf("File Size: \t\t%lld bytes\n", (long long)file_stats.st_size);
    printf("Number of Links: \t%ld\n", (long)file_stats.st_nlink);
    printf("File inode: \t\t%ld\n", (long)file_stats.st_ino);

    // 4. Determine file type using macros
    printf("File Type: \t\t");
    if (S_ISLNK(file_stats.st_mode)) printf("Symbolic Link\n");
    else if (S_ISREG(file_stats.st_mode)) printf("Regular File\n");
    else if (S_ISDIR(file_stats.st_mode)) printf("Directory\n");
    else printf("Other\n");

    return EXIT_SUCCESS;
}