1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * fs/f2fs/xattr.h
  4 *
  5 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
  6 *             http://www.samsung.com/
  7 *
  8 * Portions of this code from linux/fs/ext2/xattr.h
  9 *
 10 * On-disk format of extended attributes for the ext2 filesystem.
 11 *
 12 * (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
 13 */
 14#ifndef __F2FS_XATTR_H__
 15#define __F2FS_XATTR_H__
 16
 17#include <linux/init.h>
 18#include <linux/xattr.h>
 19
 20/* Magic value in attribute blocks */
 21#define F2FS_XATTR_MAGIC                0xF2F52011
 22
 23/* Maximum number of references to one attribute block */
 24#define F2FS_XATTR_REFCOUNT_MAX         1024
 25
 26/* Name indexes */
 27#define F2FS_SYSTEM_ADVISE_NAME			"system.advise"
 28#define F2FS_XATTR_INDEX_USER			1
 29#define F2FS_XATTR_INDEX_POSIX_ACL_ACCESS	2
 30#define F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT	3
 31#define F2FS_XATTR_INDEX_TRUSTED		4
 32#define F2FS_XATTR_INDEX_LUSTRE			5
 33#define F2FS_XATTR_INDEX_SECURITY		6
 34#define F2FS_XATTR_INDEX_ADVISE			7
 35/* Should be same as EXT4_XATTR_INDEX_ENCRYPTION */
 36#define F2FS_XATTR_INDEX_ENCRYPTION		9
 37#define F2FS_XATTR_INDEX_VERITY			11
 38
 39#define F2FS_XATTR_NAME_ENCRYPTION_CONTEXT	"c"
 40#define F2FS_XATTR_NAME_VERITY			"v"
 41
 42struct f2fs_xattr_header {
 43	__le32  h_magic;        /* magic number for identification */
 44	__le32  h_refcount;     /* reference count */
 45	__u32   h_reserved[4];  /* zero right now */
 46};
 47
 48struct f2fs_xattr_entry {
 49	__u8    e_name_index;
 50	__u8    e_name_len;
 51	__le16  e_value_size;   /* size of attribute value */
 52	char    e_name[];      /* attribute name */
 53};
 54
 55#define XATTR_HDR(ptr)		((struct f2fs_xattr_header *)(ptr))
 56#define XATTR_ENTRY(ptr)	((struct f2fs_xattr_entry *)(ptr))
 57#define XATTR_FIRST_ENTRY(ptr)	(XATTR_ENTRY(XATTR_HDR(ptr) + 1))
 58#define XATTR_ROUND		(3)
 59
 60#define XATTR_ALIGN(size)	(((size) + XATTR_ROUND) & ~XATTR_ROUND)
 61
 62#define ENTRY_SIZE(entry) (XATTR_ALIGN(sizeof(struct f2fs_xattr_entry) + \
 63			(entry)->e_name_len + le16_to_cpu((entry)->e_value_size)))
 64
 65#define XATTR_NEXT_ENTRY(entry)	((struct f2fs_xattr_entry *)((char *)(entry) +\
 66			ENTRY_SIZE(entry)))
 67
 68#define IS_XATTR_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0)
 69
 70#define list_for_each_xattr(entry, addr) \
 71		for (entry = XATTR_FIRST_ENTRY(addr);\
 72				!IS_XATTR_LAST_ENTRY(entry);\
 73				entry = XATTR_NEXT_ENTRY(entry))
 74#define VALID_XATTR_BLOCK_SIZE	(PAGE_SIZE - sizeof(struct node_footer))
 75#define XATTR_PADDING_SIZE	(sizeof(__u32))
 76#define XATTR_SIZE(i)		((F2FS_I(i)->i_xattr_nid ?		\
 77					VALID_XATTR_BLOCK_SIZE : 0) +	\
 78						(inline_xattr_size(i)))
 79#define MIN_OFFSET(i)		XATTR_ALIGN(inline_xattr_size(i) +	\
 80						VALID_XATTR_BLOCK_SIZE)
 81
 82#define MAX_VALUE_LEN(i)	(MIN_OFFSET(i) -			\
 83				sizeof(struct f2fs_xattr_header) -	\
 84				sizeof(struct f2fs_xattr_entry))
 85
 86#define MAX_INLINE_XATTR_SIZE						\
 87			(DEF_ADDRS_PER_INODE -				\
 88			F2FS_TOTAL_EXTRA_ATTR_SIZE / sizeof(__le32) -	\
 89			DEF_INLINE_RESERVED_SIZE -			\
 90			MIN_INLINE_DENTRY_SIZE / sizeof(__le32))
 91
 92/*
 93 * On-disk structure of f2fs_xattr
 94 * We use inline xattrs space + 1 block for xattr.
 95 *
 96 * +--------------------+
 97 * | f2fs_xattr_header  |
 98 * |                    |
 99 * +--------------------+
100 * | f2fs_xattr_entry   |
101 * | .e_name_index = 1  |
102 * | .e_name_len = 3    |
103 * | .e_value_size = 14 |
104 * | .e_name = "foo"    |
105 * | "value_of_xattr"   |<- value_offs = e_name + e_name_len
106 * +--------------------+
107 * | f2fs_xattr_entry   |
108 * | .e_name_index = 4  |
109 * | .e_name = "bar"    |
110 * +--------------------+
111 * |                    |
112 * |        Free        |
113 * |                    |
114 * +--------------------+<- MIN_OFFSET
115 * |   node_footer      |
116 * | (nid, ino, offset) |
117 * +--------------------+
118 *
119 **/
120
121#ifdef CONFIG_F2FS_FS_XATTR
122extern const struct xattr_handler f2fs_xattr_user_handler;
123extern const struct xattr_handler f2fs_xattr_trusted_handler;
124extern const struct xattr_handler f2fs_xattr_advise_handler;
125extern const struct xattr_handler f2fs_xattr_security_handler;
126
127extern const struct xattr_handler *f2fs_xattr_handlers[];
128
129extern int f2fs_setxattr(struct inode *, int, const char *,
130				const void *, size_t, struct page *, int);
131extern int f2fs_getxattr(struct inode *, int, const char *, void *,
132						size_t, struct page *);
133extern ssize_t f2fs_listxattr(struct dentry *, char *, size_t);
134extern int f2fs_init_xattr_caches(struct f2fs_sb_info *);
135extern void f2fs_destroy_xattr_caches(struct f2fs_sb_info *);
136#else
137
138#define f2fs_xattr_handlers	NULL
139#define f2fs_listxattr		NULL
140static inline int f2fs_setxattr(struct inode *inode, int index,
141		const char *name, const void *value, size_t size,
142		struct page *page, int flags)
143{
144	return -EOPNOTSUPP;
145}
146static inline int f2fs_getxattr(struct inode *inode, int index,
147			const char *name, void *buffer,
148			size_t buffer_size, struct page *dpage)
149{
150	return -EOPNOTSUPP;
151}
152static inline int f2fs_init_xattr_caches(struct f2fs_sb_info *sbi) { return 0; }
153static inline void f2fs_destroy_xattr_caches(struct f2fs_sb_info *sbi) { }
154#endif
155
156#ifdef CONFIG_F2FS_FS_SECURITY
157extern int f2fs_init_security(struct inode *, struct inode *,
158				const struct qstr *, struct page *);
159#else
160static inline int f2fs_init_security(struct inode *inode, struct inode *dir,
161				const struct qstr *qstr, struct page *ipage)
162{
163	return 0;
164}
165#endif
166#endif /* __F2FS_XATTR_H__ */