xattr.h

  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 MIN_INLINE_XATTR_SIZE (sizeof(struct f2fs_xattr_header) / sizeof(__le32))
 87#define MAX_INLINE_XATTR_SIZE						\
 88			(DEF_ADDRS_PER_INODE -				\
 89			F2FS_TOTAL_EXTRA_ATTR_SIZE / sizeof(__le32) -	\
 90			DEF_INLINE_RESERVED_SIZE -			\
 91			MIN_INLINE_DENTRY_SIZE / sizeof(__le32))
 92#define DEFAULT_XATTR_SLAB_SIZE	(DEFAULT_INLINE_XATTR_ADDRS *		\
 93				sizeof(__le32) + XATTR_PADDING_SIZE)
 94
 95/*
 96 * On-disk structure of f2fs_xattr
 97 * We use inline xattrs space + 1 block for xattr.
 98 *
 99 * +--------------------+
100 * | f2fs_xattr_header  |
101 * |                    |
102 * +--------------------+
103 * | f2fs_xattr_entry   |
104 * | .e_name_index = 1  |
105 * | .e_name_len = 3    |
106 * | .e_value_size = 14 |
107 * | .e_name = "foo"    |
108 * | "value_of_xattr"   |<- value_offs = e_name + e_name_len
109 * +--------------------+
110 * | f2fs_xattr_entry   |
111 * | .e_name_index = 4  |
112 * | .e_name = "bar"    |
113 * +--------------------+
114 * |                    |
115 * |        Free        |
116 * |                    |
117 * +--------------------+<- MIN_OFFSET
118 * |   node_footer      |
119 * | (nid, ino, offset) |
120 * +--------------------+
121 *
122 **/
123
124#ifdef CONFIG_F2FS_FS_XATTR
125extern const struct xattr_handler f2fs_xattr_user_handler;
126extern const struct xattr_handler f2fs_xattr_trusted_handler;
127extern const struct xattr_handler f2fs_xattr_advise_handler;
128extern const struct xattr_handler f2fs_xattr_security_handler;
129
130extern const struct xattr_handler * const f2fs_xattr_handlers[];
131
132int f2fs_setxattr(struct inode *, int, const char *, const void *,
133		size_t, struct folio *, int);
134int f2fs_getxattr(struct inode *, int, const char *, void *,
135		size_t, struct folio *);
136ssize_t f2fs_listxattr(struct dentry *, char *, size_t);
137int __init f2fs_init_xattr_cache(void);
138void f2fs_destroy_xattr_cache(void);
139#else
140
141#define f2fs_xattr_handlers	NULL
142#define f2fs_listxattr		NULL
143static inline int f2fs_setxattr(struct inode *inode, int index,
144		const char *name, const void *value, size_t size,
145		struct folio *folio, int flags)
146{
147	return -EOPNOTSUPP;
148}
149static inline int f2fs_getxattr(struct inode *inode, int index,
150			const char *name, void *buffer,
151			size_t buffer_size, struct folio *dfolio)
152{
153	return -EOPNOTSUPP;
154}
155static inline int __init f2fs_init_xattr_cache(void) { return 0; }
156static inline void f2fs_destroy_xattr_cache(void) { }
157#endif
158
159#ifdef CONFIG_F2FS_FS_SECURITY
160int f2fs_init_security(struct inode *, struct inode *,
161				const struct qstr *, struct folio *);
162#else
163static inline int f2fs_init_security(struct inode *inode, struct inode *dir,
164				const struct qstr *qstr, struct folio *ifolio)
165{
166	return 0;
167}
168#endif
169#endif /* __F2FS_XATTR_H__ */