fs: rename generic posix acl handlers

Reflect in their naming and document that they are kept around for
legacy reasons and shouldn't be used anymore by new code.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>

fs/erofs/xattr.h

@@ -49,10 +49,8 @@ static inline const char *erofs_xattr_prefix(unsigned int idx,
 	static const struct xattr_handler *xattr_handler_map[] = {
 		[EROFS_XATTR_INDEX_USER] = &erofs_xattr_user_handler,
 #ifdef CONFIG_EROFS_FS_POSIX_ACL
-		[EROFS_XATTR_INDEX_POSIX_ACL_ACCESS] =
-			&posix_acl_access_xattr_handler,
-		[EROFS_XATTR_INDEX_POSIX_ACL_DEFAULT] =
-			&posix_acl_default_xattr_handler,
+		[EROFS_XATTR_INDEX_POSIX_ACL_ACCESS] = &nop_posix_acl_access,
+		[EROFS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &nop_posix_acl_default,
 #endif
 		[EROFS_XATTR_INDEX_TRUSTED] = &erofs_xattr_trusted_handler,
 #ifdef CONFIG_EROFS_FS_SECURITY

fs/ext2/xattr.c

@@ -101,8 +101,8 @@ static void ext2_xattr_rehash(struct ext2_xattr_header *,
 static const struct xattr_handler *ext2_xattr_handler_map[] = {
 	[EXT2_XATTR_INDEX_USER]		     = &ext2_xattr_user_handler,
 #ifdef CONFIG_EXT2_FS_POSIX_ACL
-	[EXT2_XATTR_INDEX_POSIX_ACL_ACCESS]  = &posix_acl_access_xattr_handler,
-	[EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler,
+	[EXT2_XATTR_INDEX_POSIX_ACL_ACCESS]  = &nop_posix_acl_access,
+	[EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT] = &nop_posix_acl_default,
 #endif
 	[EXT2_XATTR_INDEX_TRUSTED]	     = &ext2_xattr_trusted_handler,
 #ifdef CONFIG_EXT2_FS_SECURITY

fs/ext4/xattr.c

@@ -88,8 +88,8 @@ static void ext4_xattr_rehash(struct ext4_xattr_header *);
 static const struct xattr_handler * const ext4_xattr_handler_map[] = {
 	[EXT4_XATTR_INDEX_USER]		     = &ext4_xattr_user_handler,
 #ifdef CONFIG_EXT4_FS_POSIX_ACL
-	[EXT4_XATTR_INDEX_POSIX_ACL_ACCESS]  = &posix_acl_access_xattr_handler,
-	[EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler,
+	[EXT4_XATTR_INDEX_POSIX_ACL_ACCESS]  = &nop_posix_acl_access,
+	[EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT] = &nop_posix_acl_default,
 #endif
 	[EXT4_XATTR_INDEX_TRUSTED]	     = &ext4_xattr_trusted_handler,
 #ifdef CONFIG_EXT4_FS_SECURITY

fs/f2fs/xattr.c

@@ -192,8 +192,8 @@ const struct xattr_handler f2fs_xattr_security_handler = {
 static const struct xattr_handler *f2fs_xattr_handler_map[] = {
 	[F2FS_XATTR_INDEX_USER] = &f2fs_xattr_user_handler,
 #ifdef CONFIG_F2FS_FS_POSIX_ACL
-	[F2FS_XATTR_INDEX_POSIX_ACL_ACCESS] = &posix_acl_access_xattr_handler,
-	[F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler,
+	[F2FS_XATTR_INDEX_POSIX_ACL_ACCESS] = &nop_posix_acl_access,
+	[F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &nop_posix_acl_default,
 #endif
 	[F2FS_XATTR_INDEX_TRUSTED] = &f2fs_xattr_trusted_handler,
 #ifdef CONFIG_F2FS_FS_SECURITY

fs/jffs2/xattr.c

@@ -939,10 +939,10 @@ static const char *jffs2_xattr_prefix(int xprefix, struct dentry *dentry)
 #endif
 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
 	case JFFS2_XPREFIX_ACL_ACCESS:
-		ret = &posix_acl_access_xattr_handler;
+		ret = &nop_posix_acl_access;
 		break;
 	case JFFS2_XPREFIX_ACL_DEFAULT:
-		ret = &posix_acl_default_xattr_handler;
+		ret = &nop_posix_acl_default;
 		break;
 #endif
 	case JFFS2_XPREFIX_TRUSTED:

fs/ocfs2/xattr.c

@@ -95,13 +95,11 @@ const struct xattr_handler *ocfs2_xattr_handlers[] = {
 };
 
 static const struct xattr_handler *ocfs2_xattr_handler_map[OCFS2_XATTR_MAX] = {
-	[OCFS2_XATTR_INDEX_USER]	= &ocfs2_xattr_user_handler,
-	[OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS]
-					= &posix_acl_access_xattr_handler,
-	[OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT]
-					= &posix_acl_default_xattr_handler,
-	[OCFS2_XATTR_INDEX_TRUSTED]	= &ocfs2_xattr_trusted_handler,
-	[OCFS2_XATTR_INDEX_SECURITY]	= &ocfs2_xattr_security_handler,
+	[OCFS2_XATTR_INDEX_USER]		= &ocfs2_xattr_user_handler,
+	[OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS]	= &nop_posix_acl_access,
+	[OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT]	= &nop_posix_acl_default,
+	[OCFS2_XATTR_INDEX_TRUSTED]		= &ocfs2_xattr_trusted_handler,
+	[OCFS2_XATTR_INDEX_SECURITY]		= &ocfs2_xattr_security_handler,
 };
 
 struct ocfs2_xattr_info {

fs/posix_acl.c

@@ -988,19 +988,31 @@ posix_acl_xattr_list(struct dentry *dentry)
 	return IS_POSIXACL(d_backing_inode(dentry));
 }
 
-const struct xattr_handler posix_acl_access_xattr_handler = {
+/*
+ * nop_posix_acl_access - legacy xattr handler for access POSIX ACLs
+ *
+ * This is the legacy POSIX ACL access xattr handler. It is used by some
+ * filesystems to implement their ->listxattr() inode operation. New code
+ * should never use them.
+ */
+const struct xattr_handler nop_posix_acl_access = {
 	.name = XATTR_NAME_POSIX_ACL_ACCESS,
-	.flags = ACL_TYPE_ACCESS,
 	.list = posix_acl_xattr_list,
 };
-EXPORT_SYMBOL_GPL(posix_acl_access_xattr_handler);
+EXPORT_SYMBOL_GPL(nop_posix_acl_access);
 
-const struct xattr_handler posix_acl_default_xattr_handler = {
+/*
+ * nop_posix_acl_default - legacy xattr handler for default POSIX ACLs
+ *
+ * This is the legacy POSIX ACL default xattr handler. It is used by some
+ * filesystems to implement their ->listxattr() inode operation. New code
+ * should never use them.
+ */
+const struct xattr_handler nop_posix_acl_default = {
 	.name = XATTR_NAME_POSIX_ACL_DEFAULT,
-	.flags = ACL_TYPE_DEFAULT,
 	.list = posix_acl_xattr_list,
 };
-EXPORT_SYMBOL_GPL(posix_acl_default_xattr_handler);
+EXPORT_SYMBOL_GPL(nop_posix_acl_default);
 
 int simple_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
 		   struct posix_acl *acl, int type)

include/linux/posix_acl_xattr.h

@@ -68,7 +68,8 @@ static inline int posix_acl_type(const char *name)
 	return -1;
 }
 
-extern const struct xattr_handler posix_acl_access_xattr_handler;
-extern const struct xattr_handler posix_acl_default_xattr_handler;
+/* These are legacy handlers. Don't use them for new code. */
+extern const struct xattr_handler nop_posix_acl_access;
+extern const struct xattr_handler nop_posix_acl_default;
 
 #endif	/* _POSIX_ACL_XATTR_H */