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 #define XATTR_USER_PREFIX "user." 16 17 static size_t 18 ext4_xattr_user_list(struct inode *inode, char *list, size_t list_size, 19 const char *name, size_t name_len) 20 { 21 const size_t prefix_len = sizeof(XATTR_USER_PREFIX)-1; 22 const size_t total_len = prefix_len + name_len + 1; 23 24 if (!test_opt(inode->i_sb, XATTR_USER)) 25 return 0; 26 27 if (list && total_len <= list_size) { 28 memcpy(list, XATTR_USER_PREFIX, prefix_len); 29 memcpy(list+prefix_len, name, name_len); 30 list[prefix_len + name_len] = '\0'; 31 } 32 return total_len; 33 } 34 35 static int 36 ext4_xattr_user_get(struct inode *inode, const char *name, 37 void *buffer, size_t size) 38 { 39 if (strcmp(name, "") == 0) 40 return -EINVAL; 41 if (!test_opt(inode->i_sb, XATTR_USER)) 42 return -EOPNOTSUPP; 43 return ext4_xattr_get(inode, EXT4_XATTR_INDEX_USER, name, buffer, size); 44 } 45 46 static int 47 ext4_xattr_user_set(struct inode *inode, const char *name, 48 const void *value, size_t size, int flags) 49 { 50 if (strcmp(name, "") == 0) 51 return -EINVAL; 52 if (!test_opt(inode->i_sb, XATTR_USER)) 53 return -EOPNOTSUPP; 54 return ext4_xattr_set(inode, EXT4_XATTR_INDEX_USER, name, 55 value, size, flags); 56 } 57 58 struct xattr_handler ext4_xattr_user_handler = { 59 .prefix = XATTR_USER_PREFIX, 60 .list = ext4_xattr_user_list, 61 .get = ext4_xattr_user_get, 62 .set = ext4_xattr_user_set, 63 }; 64