1 /* 2 File: linux/xattr.h 3 4 Extended attributes handling. 5 6 Copyright (C) 2001 by Andreas Gruenbacher <[email protected]> 7 Copyright (c) 2001-2002 Silicon Graphics, Inc. All Rights Reserved. 8 Copyright (c) 2004 Red Hat, Inc., James Morris <[email protected]> 9 */ 10 #ifndef _LINUX_XATTR_H 11 #define _LINUX_XATTR_H 12 13 14 #include <linux/slab.h> 15 #include <linux/types.h> 16 #include <linux/spinlock.h> 17 #include <uapi/linux/xattr.h> 18 19 struct inode; 20 struct dentry; 21 22 /* 23 * struct xattr_handler: When @name is set, match attributes with exactly that 24 * name. When @prefix is set instead, match attributes with that prefix and 25 * with a non-empty suffix. 26 */ 27 struct xattr_handler { 28 const char *name; 29 const char *prefix; 30 int flags; /* fs private flags */ 31 bool (*list)(struct dentry *dentry); 32 int (*get)(const struct xattr_handler *, struct dentry *dentry, 33 struct inode *inode, const char *name, void *buffer, 34 size_t size); 35 int (*set)(const struct xattr_handler *, struct dentry *dentry, 36 struct inode *inode, const char *name, const void *buffer, 37 size_t size, int flags); 38 }; 39 40 const char *xattr_full_name(const struct xattr_handler *, const char *); 41 42 struct xattr { 43 const char *name; 44 void *value; 45 size_t value_len; 46 }; 47 48 ssize_t xattr_getsecurity(struct inode *, const char *, void *, size_t); 49 ssize_t vfs_getxattr(struct dentry *, const char *, void *, size_t); 50 ssize_t vfs_listxattr(struct dentry *d, char *list, size_t size); 51 int __vfs_setxattr_noperm(struct dentry *, const char *, const void *, size_t, int); 52 int vfs_setxattr(struct dentry *, const char *, const void *, size_t, int); 53 int vfs_removexattr(struct dentry *, const char *); 54 55 ssize_t generic_getxattr(struct dentry *dentry, struct inode *inode, const char *name, void *buffer, size_t size); 56 ssize_t generic_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size); 57 int generic_setxattr(struct dentry *dentry, struct inode *inode, 58 const char *name, const void *value, size_t size, int flags); 59 int generic_removexattr(struct dentry *dentry, const char *name); 60 ssize_t vfs_getxattr_alloc(struct dentry *dentry, const char *name, 61 char **xattr_value, size_t size, gfp_t flags); 62 63 static inline const char *xattr_prefix(const struct xattr_handler *handler) 64 { 65 return handler->prefix ?: handler->name; 66 } 67 68 struct simple_xattrs { 69 struct list_head head; 70 spinlock_t lock; 71 }; 72 73 struct simple_xattr { 74 struct list_head list; 75 char *name; 76 size_t size; 77 char value[0]; 78 }; 79 80 /* 81 * initialize the simple_xattrs structure 82 */ 83 static inline void simple_xattrs_init(struct simple_xattrs *xattrs) 84 { 85 INIT_LIST_HEAD(&xattrs->head); 86 spin_lock_init(&xattrs->lock); 87 } 88 89 /* 90 * free all the xattrs 91 */ 92 static inline void simple_xattrs_free(struct simple_xattrs *xattrs) 93 { 94 struct simple_xattr *xattr, *node; 95 96 list_for_each_entry_safe(xattr, node, &xattrs->head, list) { 97 kfree(xattr->name); 98 kfree(xattr); 99 } 100 } 101 102 struct simple_xattr *simple_xattr_alloc(const void *value, size_t size); 103 int simple_xattr_get(struct simple_xattrs *xattrs, const char *name, 104 void *buffer, size_t size); 105 int simple_xattr_set(struct simple_xattrs *xattrs, const char *name, 106 const void *value, size_t size, int flags); 107 ssize_t simple_xattr_list(struct inode *inode, struct simple_xattrs *xattrs, char *buffer, 108 size_t size); 109 void simple_xattr_list_add(struct simple_xattrs *xattrs, 110 struct simple_xattr *new_xattr); 111 112 #endif /* _LINUX_XATTR_H */ 113