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