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
  42 struct 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
  48 struct 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[0];      /* 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(x,i)         (((x) ? VALID_XATTR_BLOCK_SIZE : 0) +   \
  77                                                 (inline_xattr_size(i)))
  78 #define MIN_OFFSET(i)           XATTR_ALIGN(inline_xattr_size(i) +      \
  79                                                 VALID_XATTR_BLOCK_SIZE)
  80
  81 #define MAX_VALUE_LEN(i)        (MIN_OFFSET(i) -                        \
  82                                 sizeof(struct f2fs_xattr_header) -      \
  83                                 sizeof(struct f2fs_xattr_entry))
  84
  85 #define MAX_INLINE_XATTR_SIZE                                           \
  86                         (DEF_ADDRS_PER_INODE -                          \
  87                         F2FS_TOTAL_EXTRA_ATTR_SIZE / sizeof(__le32) -   \
  88                         DEF_INLINE_RESERVED_SIZE -                      \
  89                         MIN_INLINE_DENTRY_SIZE / sizeof(__le32))
  90
  91 /*
  92  * On-disk structure of f2fs_xattr
  93  * We use inline xattrs space + 1 block for xattr.
  94  *
  95  * +--------------------+
  96  * | f2fs_xattr_header  |
  97  * |                    |
  98  * +--------------------+
  99  * | f2fs_xattr_entry   |
 100  * | .e_name_index = 1  |
 101  * | .e_name_len = 3    |
 102  * | .e_value_size = 14 |
 103  * | .e_name = "foo"    |
 104  * | "value_of_xattr"   |<- value_offs = e_name + e_name_len
 105  * +--------------------+
 106  * | f2fs_xattr_entry   |
 107  * | .e_name_index = 4  |
 108  * | .e_name = "bar"    |
 109  * +--------------------+
 110  * |                    |
 111  * |        Free        |
 112  * |                    |
 113  * +--------------------+<- MIN_OFFSET
 114  * |   node_footer      |
 115  * | (nid, ino, offset) |
 116  * +--------------------+
 117  *
 118  **/
 119
 120 #ifdef CONFIG_F2FS_FS_XATTR
 121 extern const struct xattr_handler f2fs_xattr_user_handler;
 122 extern const struct xattr_handler f2fs_xattr_trusted_handler;
 123 extern const struct xattr_handler f2fs_xattr_advise_handler;
 124 extern const struct xattr_handler f2fs_xattr_security_handler;
 125
 126 extern const struct xattr_handler *f2fs_xattr_handlers[];
 127
 128 extern int f2fs_setxattr(struct inode *, int, const char *,
 129                                 const void *, size_t, struct page *, int);
 130 extern int f2fs_getxattr(struct inode *, int, const char *, void *,
 131                                                 size_t, struct page *);
 132 extern ssize_t f2fs_listxattr(struct dentry *, char *, size_t);
 133 #else
 134
 135 #define f2fs_xattr_handlers     NULL
 136 static inline int f2fs_setxattr(struct inode *inode, int index,
 137                 const char *name, const void *value, size_t size,
 138                 struct page *page, int flags)
 139 {
 140         return -EOPNOTSUPP;
 141 }
 142 static inline int f2fs_getxattr(struct inode *inode, int index,
 143                         const char *name, void *buffer,
 144                         size_t buffer_size, struct page *dpage)
 145 {
 146         return -EOPNOTSUPP;
 147 }
 148 static inline ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer,
 149                 size_t buffer_size)
 150 {
 151         return -EOPNOTSUPP;
 152 }
 153 #endif
 154
 155 #ifdef CONFIG_F2FS_FS_SECURITY
 156 extern int f2fs_init_security(struct inode *, struct inode *,
 157                                 const struct qstr *, struct page *);
 158 #else
 159 static inline int f2fs_init_security(struct inode *inode, struct inode *dir,
 160                                 const struct qstr *qstr, struct page *ipage)
 161 {
 162         return 0;
 163 }
 164 #endif
 165 #endif /* __F2FS_XATTR_H__ */