fs/ocfs2/xattr_user.c

   1 /* -*- mode: c; c-basic-offset: 8; -*-
   2  * vim: noexpandtab sw=8 ts=8 sts=0:
   3  *
   4  * xattr_user.c
   5  *
   6  * Copyright (C) 2008 Oracle.  All rights reserved.
   7  *
   8  * CREDITS:
   9  * Lots of code in this file is taken from ext3.
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public
  13  * License as published by the Free Software Foundation; either
  14  * version 2 of the License, or (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  * General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public
  22  * License along with this program; if not, write to the
  23  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  24  * Boston, MA 021110-1307, USA.
  25  */
  26
  27 #include <linux/init.h>
  28 #include <linux/module.h>
  29 #include <linux/string.h>
  30
  31 #define MLOG_MASK_PREFIX ML_INODE
  32 #include <cluster/masklog.h>
  33
  34 #include "ocfs2.h"
  35 #include "alloc.h"
  36 #include "dlmglue.h"
  37 #include "file.h"
  38 #include "ocfs2_fs.h"
  39 #include "xattr.h"
  40
  41 #define XATTR_USER_PREFIX "user."
  42
  43 static size_t ocfs2_xattr_user_list(struct inode *inode, char *list,
  44                                     size_t list_size, const char *name,
  45                                     size_t name_len)
  46 {
  47         const size_t prefix_len = sizeof(XATTR_USER_PREFIX) - 1;
  48         const size_t total_len = prefix_len + name_len + 1;
  49         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  50
  51         if (osb->s_mount_opt & OCFS2_MOUNT_NOUSERXATTR)
  52                 return 0;
  53
  54         if (list && total_len <= list_size) {
  55                 memcpy(list, XATTR_USER_PREFIX, prefix_len);
  56                 memcpy(list + prefix_len, name, name_len);
  57                 list[prefix_len + name_len] = '\0';
  58         }
  59         return total_len;
  60 }
  61
  62 static int ocfs2_xattr_user_get(struct inode *inode, const char *name,
  63                                 void *buffer, size_t size)
  64 {
  65         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  66
  67         if (strcmp(name, "") == 0)
  68                 return -EINVAL;
  69         if (osb->s_mount_opt & OCFS2_MOUNT_NOUSERXATTR)
  70                 return -EOPNOTSUPP;
  71         return ocfs2_xattr_get(inode, OCFS2_XATTR_INDEX_USER, name,
  72                                buffer, size);
  73 }
  74
  75 static int ocfs2_xattr_user_set(struct inode *inode, const char *name,
  76                                 const void *value, size_t size, int flags)
  77 {
  78         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  79
  80         if (strcmp(name, "") == 0)
  81                 return -EINVAL;
  82         if (osb->s_mount_opt & OCFS2_MOUNT_NOUSERXATTR)
  83                 return -EOPNOTSUPP;
  84
  85         return ocfs2_xattr_set(inode, OCFS2_XATTR_INDEX_USER, name, value,
  86                                size, flags);
  87 }
  88
  89 struct xattr_handler ocfs2_xattr_user_handler = {
  90         .prefix = XATTR_USER_PREFIX,
  91         .list   = ocfs2_xattr_user_list,
  92         .get    = ocfs2_xattr_user_get,
  93         .set    = ocfs2_xattr_user_set,
  94 };