Merge branch 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull more vfs updates from Al Viro:
 "Assorted cleanups and fixes.

  In the "trivial API change" department - ->d_compare() losing 'parent'
  argument"

* 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  cachefiles: Fix race between inactivating and culling a cache object
  9p: use clone_fid()
  9p: fix braino introduced in "9p: new helper - v9fs_parent_fid()"
  vfs: make dentry_needs_remove_privs() internal
  vfs: remove file_needs_remove_privs()
  vfs: fix deadlock in file_remove_privs() on overlayfs
  get rid of 'parent' argument of ->d_compare()
  cifs, msdos, vfat, hfs+: don't bother with parent in ->d_compare()
  affs ->d_compare(): don't bother with ->d_inode
  fold _d_rehash() and __d_rehash() together
  fold dentry_rcuwalk_invalidate() into its only remaining caller

Author: torvalds

Documentation/filesystems/Locking

@@ -12,7 +12,7 @@ prototypes:
 	int (*d_revalidate)(struct dentry *, unsigned int);
 	int (*d_weak_revalidate)(struct dentry *, unsigned int);
 	int (*d_hash)(const struct dentry *, struct qstr *);
-	int (*d_compare)(const struct dentry *, const struct dentry *,
+	int (*d_compare)(const struct dentry *,
 			unsigned int, const char *, const struct qstr *);
 	int (*d_delete)(struct dentry *);
 	int (*d_init)(struct dentry *);

Documentation/filesystems/porting

@@ -585,3 +585,10 @@ in your dentry operations instead.
 	in the instances.  Rationale: !@#!@# security_d_instantiate() needs to be
 	called before we attach dentry to inode and !@#!@##!@$!$#!@#$!@$!@$ smack
 	->d_instantiate() uses not just ->getxattr() but ->setxattr() as well.
+--
+[mandatory]
+	->d_compare() doesn't get parent as a separate argument anymore.  If you
+	used it for finding the struct super_block involved, dentry->d_sb will
+	work just as well; if it's something more complicated, use dentry->d_parent.
+	Just be careful not to assume that fetching it more than once will yield
+	the same value - in RCU mode it could change under you.

Documentation/filesystems/vfs.txt

@@ -931,7 +931,7 @@ struct dentry_operations {
 	int (*d_revalidate)(struct dentry *, unsigned int);
 	int (*d_weak_revalidate)(struct dentry *, unsigned int);
 	int (*d_hash)(const struct dentry *, struct qstr *);
-	int (*d_compare)(const struct dentry *, const struct dentry *,
+	int (*d_compare)(const struct dentry *,
 			unsigned int, const char *, const struct qstr *);
 	int (*d_delete)(const struct dentry *);
 	int (*d_init)(struct dentry *);

drivers/staging/lustre/lustre/llite/dcache.c

@@ -78,7 +78,7 @@ static void ll_release(struct dentry *de)
  * INVALID) so d_lookup() matches it, but we have no lock on it (so
  * lock_match() fails) and we spin around real_lookup().
  */
-static int ll_dcompare(const struct dentry *parent, const struct dentry *dentry,
+static int ll_dcompare(const struct dentry *dentry,
 		       unsigned int len, const char *str,
 		       const struct qstr *name)
 {

fs/9p/fid.c

@@ -257,36 +257,12 @@ struct p9_fid *v9fs_fid_lookup(struct dentry *dentry)
 	return v9fs_fid_lookup_with_uid(dentry, uid, any);
 }
 
-struct p9_fid *v9fs_fid_clone(struct dentry *dentry)
-{
-	struct p9_fid *fid, *ret;
-
-	fid = v9fs_fid_lookup(dentry);
-	if (IS_ERR(fid))
-		return fid;
-
-	ret = p9_client_walk(fid, 0, NULL, 1);
-	return ret;
-}
-
-static struct p9_fid *v9fs_fid_clone_with_uid(struct dentry *dentry, kuid_t uid)
-{
-	struct p9_fid *fid, *ret;
-
-	fid = v9fs_fid_lookup_with_uid(dentry, uid, 0);
-	if (IS_ERR(fid))
-		return fid;
-
-	ret = p9_client_walk(fid, 0, NULL, 1);
-	return ret;
-}
-
 struct p9_fid *v9fs_writeback_fid(struct dentry *dentry)
 {
 	int err;
 	struct p9_fid *fid;
 
-	fid = v9fs_fid_clone_with_uid(dentry, GLOBAL_ROOT_UID);
+	fid = clone_fid(v9fs_fid_lookup_with_uid(dentry, GLOBAL_ROOT_UID, 0));
 	if (IS_ERR(fid))
 		goto error_out;
 	/*

fs/9p/fid.h

@@ -28,7 +28,14 @@ static inline struct p9_fid *v9fs_parent_fid(struct dentry *dentry)
 {
 	return v9fs_fid_lookup(dentry->d_parent);
 }
-struct p9_fid *v9fs_fid_clone(struct dentry *dentry);
 void v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid);
 struct p9_fid *v9fs_writeback_fid(struct dentry *dentry);
+static inline struct p9_fid *clone_fid(struct p9_fid *fid)
+{
+	return IS_ERR(fid) ? fid :  p9_client_walk(fid, 0, NULL, 1);
+}
+static inline struct p9_fid *v9fs_fid_clone(struct dentry *dentry)
+{
+	return clone_fid(v9fs_fid_lookup(dentry));
+}
 #endif

fs/9p/vfs_inode.c

@@ -661,7 +661,7 @@ v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
 	}
 
 	/* clone a fid to use for creation */
-	ofid = p9_client_walk(dfid, 0, NULL, 1);
+	ofid = clone_fid(dfid);
 	if (IS_ERR(ofid)) {
 		err = PTR_ERR(ofid);
 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
@@ -975,13 +975,13 @@ v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	if (IS_ERR(oldfid))
 		return PTR_ERR(oldfid);
 
-	olddirfid = v9fs_parent_fid(old_dentry);
+	olddirfid = clone_fid(v9fs_parent_fid(old_dentry));
 	if (IS_ERR(olddirfid)) {
 		retval = PTR_ERR(olddirfid);
 		goto done;
 	}
 
-	newdirfid = v9fs_parent_fid(new_dentry);
+	newdirfid = clone_fid(v9fs_parent_fid(new_dentry));
 	if (IS_ERR(newdirfid)) {
 		retval = PTR_ERR(newdirfid);
 		goto clunk_olddir;

fs/9p/vfs_inode_dotl.c

@@ -281,7 +281,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
 	}
 
 	/* clone a fid to use for creation */
-	ofid = p9_client_walk(dfid, 0, NULL, 1);
+	ofid = clone_fid(dfid);
 	if (IS_ERR(ofid)) {
 		err = PTR_ERR(ofid);
 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);

fs/9p/xattr.c

@@ -97,8 +97,6 @@ int v9fs_xattr_set(struct dentry *dentry, const char *name,
 		   const void *value, size_t value_len, int flags)
 {
 	struct p9_fid *fid = v9fs_fid_lookup(dentry);
-	if (IS_ERR(fid))
-		return PTR_ERR(fid);
 	return v9fs_fid_xattr_set(fid, name, value, value_len, flags);
 }
 
@@ -115,7 +113,7 @@ int v9fs_fid_xattr_set(struct p9_fid *fid, const char *name,
 		 name, value_len, flags);
 
 	/* Clone it */
-	fid = p9_client_walk(fid, 0, NULL, 1);
+	fid = clone_fid(fid);
 	if (IS_ERR(fid))
 		return PTR_ERR(fid);
 

fs/adfs/dir.c

@@ -227,7 +227,7 @@ adfs_hash(const struct dentry *parent, struct qstr *qstr)
  * requirements of the underlying filesystem.
  */
 static int
-adfs_compare(const struct dentry *parent, const struct dentry *dentry,
+adfs_compare(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
 	int i;