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/module.h> 9 #include <linux/string.h> 10 #include <linux/fs.h> 11 #include "ext4_jbd2.h" 12 #include "ext4.h" 13 #include "xattr.h" 14 15 static size_t 16 ext4_xattr_user_list(struct inode *inode, 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(inode->i_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 33 static int 34 ext4_xattr_user_get(struct inode *inode, const char *name, 35 void *buffer, size_t size) 36 { 37 if (strcmp(name, "") == 0) 38 return -EINVAL; 39 if (!test_opt(inode->i_sb, XATTR_USER)) 40 return -EOPNOTSUPP; 41 return ext4_xattr_get(inode, EXT4_XATTR_INDEX_USER, name, buffer, size); 42 } 43 44 static int 45 ext4_xattr_user_set(struct inode *inode, const char *name, 46 const void *value, size_t size, int flags) 47 { 48 if (strcmp(name, "") == 0) 49 return -EINVAL; 50 if (!test_opt(inode->i_sb, XATTR_USER)) 51 return -EOPNOTSUPP; 52 return ext4_xattr_set(inode, EXT4_XATTR_INDEX_USER, name, 53 value, size, flags); 54 } 55 56 struct xattr_handler ext4_xattr_user_handler = { 57 .prefix = XATTR_USER_PREFIX, 58 .list = ext4_xattr_user_list, 59 .get = ext4_xattr_user_get, 60 .set = ext4_xattr_user_set, 61 }; 62