| 1 | /* |
| 2 | File: linux/xattr.h |
| 3 | |
| 4 | Extended attributes handling. |
| 5 | |
| 6 | Copyright (C) 2001 by Andreas Gruenbacher <a.gruenbacher@computer.org> |
| 7 | Copyright (c) 2001-2002 Silicon Graphics, Inc. All Rights Reserved. |
| 8 | Copyright (c) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com> |
| 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 | const char *name, const void *buffer, size_t size, |
| 37 | 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, const char *name, const void *value, size_t size, int flags); |
| 58 | int generic_removexattr(struct dentry *dentry, const char *name); |
| 59 | ssize_t vfs_getxattr_alloc(struct dentry *dentry, const char *name, |
| 60 | char **xattr_value, size_t size, gfp_t flags); |
| 61 | |
| 62 | static inline const char *xattr_prefix(const struct xattr_handler *handler) |
| 63 | { |
| 64 | return handler->prefix ?: handler->name; |
| 65 | } |
| 66 | |
| 67 | struct simple_xattrs { |
| 68 | struct list_head head; |
| 69 | spinlock_t lock; |
| 70 | }; |
| 71 | |
| 72 | struct simple_xattr { |
| 73 | struct list_head list; |
| 74 | char *name; |
| 75 | size_t size; |
| 76 | char value[0]; |
| 77 | }; |
| 78 | |
| 79 | /* |
| 80 | * initialize the simple_xattrs structure |
| 81 | */ |
| 82 | static inline void simple_xattrs_init(struct simple_xattrs *xattrs) |
| 83 | { |
| 84 | INIT_LIST_HEAD(&xattrs->head); |
| 85 | spin_lock_init(&xattrs->lock); |
| 86 | } |
| 87 | |
| 88 | /* |
| 89 | * free all the xattrs |
| 90 | */ |
| 91 | static inline void simple_xattrs_free(struct simple_xattrs *xattrs) |
| 92 | { |
| 93 | struct simple_xattr *xattr, *node; |
| 94 | |
| 95 | list_for_each_entry_safe(xattr, node, &xattrs->head, list) { |
| 96 | kfree(xattr->name); |
| 97 | kfree(xattr); |
| 98 | } |
| 99 | } |
| 100 | |
| 101 | struct simple_xattr *simple_xattr_alloc(const void *value, size_t size); |
| 102 | int simple_xattr_get(struct simple_xattrs *xattrs, const char *name, |
| 103 | void *buffer, size_t size); |
| 104 | int simple_xattr_set(struct simple_xattrs *xattrs, const char *name, |
| 105 | const void *value, size_t size, int flags); |
| 106 | ssize_t simple_xattr_list(struct inode *inode, struct simple_xattrs *xattrs, char *buffer, |
| 107 | size_t size); |
| 108 | void simple_xattr_list_add(struct simple_xattrs *xattrs, |
| 109 | struct simple_xattr *new_xattr); |
| 110 | |
| 111 | #endif /* _LINUX_XATTR_H */ |