switch d_materialise_unique() users to d_splice_alias()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Documentation/filesystems/nfs/Exporting

@@ -72,24 +72,11 @@ c/ Helper routines to allocate anonymous dentries, and to help attach
         DCACHE_DISCONNECTED) dentry is allocated and attached.
       In the case of a directory, care is taken that only one dentry
       can ever be attached.
-    d_splice_alias(inode, dentry) or d_materialise_unique(dentry, inode)
+    d_splice_alias(inode, dentry) will introduce a new dentry into the tree;
-      will introduce a new dentry into the tree; either the passed-in
+      either the passed-in dentry or a preexisting alias for the given inode
-      dentry or a preexisting alias for the given inode (such as an
+      (such as an anonymous one created by d_obtain_alias), if appropriate.
-      anonymous one created by d_obtain_alias), if appropriate.  The two
+      It returns NULL when the passed-in dentry is used, following the calling
-      functions differ in their handling of directories with preexisting
+      convention of ->lookup.
-      aliases:
-        d_splice_alias will use any existing IS_ROOT dentry, but it will
-	  return -EIO rather than try to move a dentry with a different
-	  parent.  This is appropriate for local filesystems, which
-	  should never see such an alias unless the filesystem is
-	  corrupted somehow (for example, if two on-disk directory
-	  entries refer to the same directory.)
-	d_materialise_unique will attempt to move any dentry.  This is
-	  appropriate for distributed filesystems, where finding a
-	  directory other than where we last cached it may be a normal
-	  consequence of concurrent operations on other hosts.
-      Both functions return NULL when the passed-in dentry is used,
-      following the calling convention of ->lookup.
 
  
 Filesystem Issues

Documentation/filesystems/porting

@@ -463,3 +463,7 @@ in your dentry operations instead.
 	of the in-tree instances did).  inode_hash_lock is still held,
 	of course, so they are still serialized wrt removal from inode hash,
 	as well as wrt set() callback of iget5_locked().
+--
+[mandatory]
+	d_materialise_unique() is gone; d_splice_alias() does everything you
+	need now.  Remember that they have opposite orders of arguments ;-/

fs/9p/vfs_inode.c

@@ -832,7 +832,7 @@ struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
 	 * moved b under k and client parallely did a lookup for
 	 * k/b.
 	 */
-	res = d_materialise_unique(dentry, inode);
+	res = d_splice_alias(inode, dentry);
 	if (!res)
 		v9fs_fid_add(dentry, fid);
 	else if (!IS_ERR(res))

fs/btrfs/inode.c

@@ -5303,7 +5303,7 @@ static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
 			return ERR_CAST(inode);
 	}
 
-	return d_materialise_unique(dentry, inode);
+	return d_splice_alias(inode, dentry);
 }
 
 unsigned char btrfs_filetype_table[] = {

fs/ceph/inode.c

@@ -967,7 +967,7 @@ static struct dentry *splice_dentry(struct dentry *dn, struct inode *in,
 	/* dn must be unhashed */
 	if (!d_unhashed(dn))
 		d_drop(dn);
-	realdn = d_materialise_unique(dn, in);
+	realdn = d_splice_alias(in, dn);
 	if (IS_ERR(realdn)) {
 		pr_err("splice_dentry error %ld %p inode %p ino %llx.%llx\n",
 		       PTR_ERR(realdn), dn, in, ceph_vinop(in));

fs/cifs/readdir.c

@@ -123,7 +123,7 @@ cifs_prime_dcache(struct dentry *parent, struct qstr *name,
 	if (!inode)
 		goto out;
 
-	alias = d_materialise_unique(dentry, inode);
+	alias = d_splice_alias(inode, dentry);
 	if (alias && !IS_ERR(alias))
 		dput(alias);
 out:

fs/fuse/dir.c

@@ -372,7 +372,7 @@ static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
 	if (inode && get_node_id(inode) == FUSE_ROOT_ID)
 		goto out_iput;
 
-	newent = d_materialise_unique(entry, inode);
+	newent = d_splice_alias(inode, entry);
 	err = PTR_ERR(newent);
 	if (IS_ERR(newent))
 		goto out_err;
@@ -1320,7 +1320,7 @@ static int fuse_direntplus_link(struct file *file,
 	if (!inode)
 		goto out;
 
-	alias = d_materialise_unique(dentry, inode);
+	alias = d_splice_alias(inode, dentry);
 	err = PTR_ERR(alias);
 	if (IS_ERR(alias))
 		goto out;

fs/kernfs/dir.c

@@ -807,7 +807,7 @@ static struct dentry *kernfs_iop_lookup(struct inode *dir,
 	}
 
 	/* instantiate and hash dentry */
-	ret = d_materialise_unique(dentry, inode);
+	ret = d_splice_alias(inode, dentry);
  out_unlock:
 	mutex_unlock(&kernfs_mutex);
 	return ret;

fs/nfs/dir.c

@@ -499,7 +499,7 @@ void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry)
 	if (IS_ERR(inode))
 		goto out;
 
-	alias = d_materialise_unique(dentry, inode);
+	alias = d_splice_alias(inode, dentry);
 	if (IS_ERR(alias))
 		goto out;
 	else if (alias) {
@@ -1393,7 +1393,7 @@ struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, unsigned in
 	nfs_advise_use_readdirplus(dir);
 
 no_entry:
-	res = d_materialise_unique(dentry, inode);
+	res = d_splice_alias(inode, dentry);
 	if (res != NULL) {
 		if (IS_ERR(res))
 			goto out_unblock_sillyrename;

fs/nfs/getroot.c

@@ -51,7 +51,7 @@ static int nfs_superblock_set_dummy_root(struct super_block *sb, struct inode *i
 		/*
 		 * Ensure that this dentry is invisible to d_find_alias().
 		 * Otherwise, it may be spliced into the tree by
-		 * d_materialise_unique if a parent directory from the same
+		 * d_splice_alias if a parent directory from the same
 		 * filesystem gets mounted at a later time.
 		 * This again causes shrink_dcache_for_umount_subtree() to
 		 * Oops, since the test for IS_ROOT() will fail.

include/linux/dcache.h

@@ -230,7 +230,6 @@ extern seqlock_t rename_lock;
  */
 extern void d_instantiate(struct dentry *, struct inode *);
 extern struct dentry * d_instantiate_unique(struct dentry *, struct inode *);
-#define d_materialise_unique(d, i) d_splice_alias(i, d)
 extern int d_instantiate_no_diralias(struct dentry *, struct inode *);
 extern void __d_drop(struct dentry *dentry);
 extern void d_drop(struct dentry *dentry);