LXR linux/fs/f2fs/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 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__ */
 167