xref: /openbmc/linux/fs/erofs/xattr.h (revision a5488f29)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2017-2018 HUAWEI, Inc.
4  *             https://www.huawei.com/
5  */
6 #ifndef __EROFS_XATTR_H
7 #define __EROFS_XATTR_H
8 
9 #include "internal.h"
10 #include <linux/posix_acl_xattr.h>
11 #include <linux/xattr.h>
12 
13 /* Attribute not found */
14 #define ENOATTR         ENODATA
15 
16 static inline unsigned int inlinexattr_header_size(struct inode *inode)
17 {
18 	return sizeof(struct erofs_xattr_ibody_header) +
19 		sizeof(u32) * EROFS_I(inode)->xattr_shared_count;
20 }
21 
22 static inline erofs_blk_t xattrblock_addr(struct erofs_sb_info *sbi,
23 					  unsigned int xattr_id)
24 {
25 #ifdef CONFIG_EROFS_FS_XATTR
26 	return sbi->xattr_blkaddr +
27 		xattr_id * sizeof(__u32) / EROFS_BLKSIZ;
28 #else
29 	return 0;
30 #endif
31 }
32 
33 static inline unsigned int xattrblock_offset(struct erofs_sb_info *sbi,
34 					     unsigned int xattr_id)
35 {
36 	return (xattr_id * sizeof(__u32)) % EROFS_BLKSIZ;
37 }
38 
39 #ifdef CONFIG_EROFS_FS_XATTR
40 extern const struct xattr_handler erofs_xattr_user_handler;
41 extern const struct xattr_handler erofs_xattr_trusted_handler;
42 extern const struct xattr_handler erofs_xattr_security_handler;
43 
44 static inline const char *erofs_xattr_prefix(unsigned int idx,
45 					     struct dentry *dentry)
46 {
47 	const struct xattr_handler *handler = NULL;
48 
49 	static const struct xattr_handler *xattr_handler_map[] = {
50 		[EROFS_XATTR_INDEX_USER] = &erofs_xattr_user_handler,
51 #ifdef CONFIG_EROFS_FS_POSIX_ACL
52 		[EROFS_XATTR_INDEX_POSIX_ACL_ACCESS] =
53 			&posix_acl_access_xattr_handler,
54 		[EROFS_XATTR_INDEX_POSIX_ACL_DEFAULT] =
55 			&posix_acl_default_xattr_handler,
56 #endif
57 		[EROFS_XATTR_INDEX_TRUSTED] = &erofs_xattr_trusted_handler,
58 #ifdef CONFIG_EROFS_FS_SECURITY
59 		[EROFS_XATTR_INDEX_SECURITY] = &erofs_xattr_security_handler,
60 #endif
61 	};
62 
63 	if (idx && idx < ARRAY_SIZE(xattr_handler_map))
64 		handler = xattr_handler_map[idx];
65 
66 	if (!xattr_handler_can_list(handler, dentry))
67 		return NULL;
68 
69 	return xattr_prefix(handler);
70 }
71 
72 extern const struct xattr_handler *erofs_xattr_handlers[];
73 
74 int erofs_getxattr(struct inode *, int, const char *, void *, size_t);
75 ssize_t erofs_listxattr(struct dentry *, char *, size_t);
76 #else
77 static inline int erofs_getxattr(struct inode *inode, int index,
78 				 const char *name, void *buffer,
79 				 size_t buffer_size)
80 {
81 	return -EOPNOTSUPP;
82 }
83 
84 #define erofs_listxattr (NULL)
85 #define erofs_xattr_handlers (NULL)
86 #endif	/* !CONFIG_EROFS_FS_XATTR */
87 
88 #ifdef CONFIG_EROFS_FS_POSIX_ACL
89 struct posix_acl *erofs_get_acl(struct inode *inode, int type, bool rcu);
90 #else
91 #define erofs_get_acl	(NULL)
92 #endif
93 
94 #endif
95