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1/* SPDX-License-Identifier: GPL-2.0 */2/*3 File: linux/ext2_xattr.h4 5 On-disk format of extended attributes for the ext2 filesystem.6 7 (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>8*/9 10#include <linux/init.h>11#include <linux/xattr.h>12 13/* Magic value in attribute blocks */14#define EXT2_XATTR_MAGIC 0xEA02000015 16/* Maximum number of references to one attribute block */17#define EXT2_XATTR_REFCOUNT_MAX 102418 19/* Name indexes */20#define EXT2_XATTR_INDEX_USER 121#define EXT2_XATTR_INDEX_POSIX_ACL_ACCESS 222#define EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT 323#define EXT2_XATTR_INDEX_TRUSTED 424#define EXT2_XATTR_INDEX_LUSTRE 525#define EXT2_XATTR_INDEX_SECURITY 626 27struct ext2_xattr_header {28 __le32 h_magic; /* magic number for identification */29 __le32 h_refcount; /* reference count */30 __le32 h_blocks; /* number of disk blocks used */31 __le32 h_hash; /* hash value of all attributes */32 __u32 h_reserved[4]; /* zero right now */33};34 35struct ext2_xattr_entry {36 __u8 e_name_len; /* length of name */37 __u8 e_name_index; /* attribute name index */38 __le16 e_value_offs; /* offset in disk block of value */39 __le32 e_value_block; /* disk block attribute is stored on (n/i) */40 __le32 e_value_size; /* size of attribute value */41 __le32 e_hash; /* hash value of name and value */42 char e_name[]; /* attribute name */43};44 45#define EXT2_XATTR_PAD_BITS 246#define EXT2_XATTR_PAD (1<<EXT2_XATTR_PAD_BITS)47#define EXT2_XATTR_ROUND (EXT2_XATTR_PAD-1)48#define EXT2_XATTR_LEN(name_len) \49 (((name_len) + EXT2_XATTR_ROUND + \50 sizeof(struct ext2_xattr_entry)) & ~EXT2_XATTR_ROUND)51#define EXT2_XATTR_NEXT(entry) \52 ( (struct ext2_xattr_entry *)( \53 (char *)(entry) + EXT2_XATTR_LEN((entry)->e_name_len)) )54#define EXT2_XATTR_SIZE(size) \55 (((size) + EXT2_XATTR_ROUND) & ~EXT2_XATTR_ROUND)56 57struct mb_cache;58 59# ifdef CONFIG_EXT2_FS_XATTR60 61extern const struct xattr_handler ext2_xattr_user_handler;62extern const struct xattr_handler ext2_xattr_trusted_handler;63extern const struct xattr_handler ext2_xattr_security_handler;64 65extern ssize_t ext2_listxattr(struct dentry *, char *, size_t);66 67extern int ext2_xattr_get(struct inode *, int, const char *, void *, size_t);68extern int ext2_xattr_set(struct inode *, int, const char *, const void *, size_t, int);69 70extern void ext2_xattr_delete_inode(struct inode *);71 72extern struct mb_cache *ext2_xattr_create_cache(void);73extern void ext2_xattr_destroy_cache(struct mb_cache *cache);74 75extern const struct xattr_handler * const ext2_xattr_handlers[];76 77# else /* CONFIG_EXT2_FS_XATTR */78 79static inline int80ext2_xattr_get(struct inode *inode, int name_index,81 const char *name, void *buffer, size_t size)82{83 return -EOPNOTSUPP;84}85 86static inline int87ext2_xattr_set(struct inode *inode, int name_index, const char *name,88 const void *value, size_t size, int flags)89{90 return -EOPNOTSUPP;91}92 93static inline void94ext2_xattr_delete_inode(struct inode *inode)95{96}97 98static inline void ext2_xattr_destroy_cache(struct mb_cache *cache)99{100}101 102#define ext2_xattr_handlers NULL103#define ext2_listxattr NULL104 105# endif /* CONFIG_EXT2_FS_XATTR */106 107#ifdef CONFIG_EXT2_FS_SECURITY108extern int ext2_init_security(struct inode *inode, struct inode *dir,109 const struct qstr *qstr);110#else111static inline int ext2_init_security(struct inode *inode, struct inode *dir,112 const struct qstr *qstr)113{114 return 0;115}116#endif117