1/* 2 * linux/fs/ext4/xattr_user.c 3 * Handler for extended user attributes. 4 * 5 * Copyright (C) 2001 by Andreas Gruenbacher, <a.gruenbacher@computer.org> 6 */ 7 8#include <linux/string.h> 9#include <linux/fs.h> 10#include "ext4_jbd2.h" 11#include "ext4.h" 12#include "xattr.h" 13 14static size_t 15ext4_xattr_user_list(const struct xattr_handler *handler, 16 struct dentry *dentry, char *list, size_t list_size, 17 const char *name, size_t name_len) 18{ 19 const size_t prefix_len = XATTR_USER_PREFIX_LEN; 20 const size_t total_len = prefix_len + name_len + 1; 21 22 if (!test_opt(dentry->d_sb, XATTR_USER)) 23 return 0; 24 25 if (list && total_len <= list_size) { 26 memcpy(list, XATTR_USER_PREFIX, prefix_len); 27 memcpy(list+prefix_len, name, name_len); 28 list[prefix_len + name_len] = '\0'; 29 } 30 return total_len; 31} 32 33static int 34ext4_xattr_user_get(const struct xattr_handler *handler, 35 struct dentry *dentry, const char *name, 36 void *buffer, size_t size) 37{ 38 if (strcmp(name, "") == 0) 39 return -EINVAL; 40 if (!test_opt(dentry->d_sb, XATTR_USER)) 41 return -EOPNOTSUPP; 42 return ext4_xattr_get(d_inode(dentry), EXT4_XATTR_INDEX_USER, 43 name, buffer, size); 44} 45 46static int 47ext4_xattr_user_set(const struct xattr_handler *handler, 48 struct dentry *dentry, const char *name, 49 const void *value, size_t size, int flags) 50{ 51 if (strcmp(name, "") == 0) 52 return -EINVAL; 53 if (!test_opt(dentry->d_sb, XATTR_USER)) 54 return -EOPNOTSUPP; 55 return ext4_xattr_set(d_inode(dentry), EXT4_XATTR_INDEX_USER, 56 name, value, size, flags); 57} 58 59const struct xattr_handler ext4_xattr_user_handler = { 60 .prefix = XATTR_USER_PREFIX, 61 .list = ext4_xattr_user_list, 62 .get = ext4_xattr_user_get, 63 .set = ext4_xattr_user_set, 64}; 65