Merge tag 'iversion-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux

Pull i_version updates from Jeff Layton:
 "This overhauls how we handle i_version queries from nfsd.

  Instead of having special routines and grabbing the i_version field
  directly out of the inode in some cases, we've moved most of the
  handling into the various filesystems' getattr operations. As a bonus,
  this makes ceph's change attribute usable by knfsd as well.

  This should pave the way for future work to make this value queryable
  by userland, and to make it more resilient against rolling back on a
  crash"

* tag 'iversion-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
  nfsd: remove fetch_iversion export operation
  nfsd: use the getattr operation to fetch i_version
  nfsd: move nfsd4_change_attribute to nfsfh.c
  ceph: report the inode version in getattr if requested
  nfs: report the inode version in getattr if requested
  vfs: plumb i_version handling into struct kstat
  fs: clarify when the i_version counter must be updated
  fs: uninline inode_query_iversion

2 files changed, 12 insertions, 11 deletions

diff --git a/fs/nfs/export.c b/fs/nfs/export.c
index 01596f2d0a1e..1a9d5aa51dfb 100644
--- a/fs/nfs/export.c
+++ b/fs/nfs/export.c
@@ -145,17 +145,10 @@ out:
 	return parent;
 }
 
-static u64 nfs_fetch_iversion(struct inode *inode)
-{
-	nfs_revalidate_inode(inode, NFS_INO_INVALID_CHANGE);
-	return inode_peek_iversion_raw(inode);
-}
-
 const struct export_operations nfs_export_ops = {
 	.encode_fh = nfs_encode_fh,
 	.fh_to_dentry = nfs_fh_to_dentry,
 	.get_parent = nfs_get_parent,
-	.fetch_iversion = nfs_fetch_iversion,
 	.flags = EXPORT_OP_NOWCC|EXPORT_OP_NOSUBTREECHK|
 		EXPORT_OP_CLOSE_BEFORE_UNLINK|EXPORT_OP_REMOTE_FS|
 		EXPORT_OP_NOATOMIC_ATTR,
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index e98ee7599eeb..756ad4fa6f2a 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -825,6 +825,8 @@ static u32 nfs_get_valid_attrmask(struct inode *inode)
 		reply_mask |= STATX_UID | STATX_GID;
 	if (!(cache_validity & NFS_INO_INVALID_BLOCKS))
 		reply_mask |= STATX_BLOCKS;
+	if (!(cache_validity & NFS_INO_INVALID_CHANGE))
+		reply_mask |= STATX_CHANGE_COOKIE;
 	return reply_mask;
 }
 
@@ -843,7 +845,8 @@ int nfs_getattr(struct user_namespace *mnt_userns, const struct path *path,
 
 	request_mask &= STATX_TYPE | STATX_MODE | STATX_NLINK | STATX_UID |
 			STATX_GID | STATX_ATIME | STATX_MTIME | STATX_CTIME |
-			STATX_INO | STATX_SIZE | STATX_BLOCKS;
+			STATX_INO | STATX_SIZE | STATX_BLOCKS | STATX_BTIME |
+			STATX_CHANGE_COOKIE;
 
 	if ((query_flags & AT_STATX_DONT_SYNC) && !force_sync) {
 		if (readdirplus_enabled)
@@ -851,8 +854,8 @@ int nfs_getattr(struct user_namespace *mnt_userns, const struct path *path,
 		goto out_no_revalidate;
 	}
 
-	/* Flush out writes to the server in order to update c/mtime.  */
-	if ((request_mask & (STATX_CTIME | STATX_MTIME)) &&
+	/* Flush out writes to the server in order to update c/mtime/version.  */
+	if ((request_mask & (STATX_CTIME | STATX_MTIME | STATX_CHANGE_COOKIE)) &&
 	    S_ISREG(inode->i_mode))
 		filemap_write_and_wait(inode->i_mapping);
 
@@ -872,7 +875,8 @@ int nfs_getattr(struct user_namespace *mnt_userns, const struct path *path,
 	/* Is the user requesting attributes that might need revalidation? */
 	if (!(request_mask & (STATX_MODE|STATX_NLINK|STATX_ATIME|STATX_CTIME|
 					STATX_MTIME|STATX_UID|STATX_GID|
-					STATX_SIZE|STATX_BLOCKS)))
+					STATX_SIZE|STATX_BLOCKS|
+					STATX_CHANGE_COOKIE)))
 		goto out_no_revalidate;
 
 	/* Check whether the cached attributes are stale */
@@ -910,6 +914,10 @@ out_no_revalidate:
 
 	generic_fillattr(&init_user_ns, inode, stat);
 	stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
+	stat->change_cookie = inode_peek_iversion_raw(inode);
+	stat->attributes_mask |= STATX_ATTR_CHANGE_MONOTONIC;
+	if (server->change_attr_type != NFS4_CHANGE_TYPE_IS_UNDEFINED)
+		stat->attributes |= STATX_ATTR_CHANGE_MONOTONIC;
 	if (S_ISDIR(inode->i_mode))
 		stat->blksize = NFS_SERVER(inode)->dtsize;
 out: