fs/jfs/acl.c

   1 /*
   2  *   Copyright (C) International Business Machines  Corp., 2002-2004
   3  *   Copyright (C) Andreas Gruenbacher, 2001
   4  *   Copyright (C) Linus Torvalds, 1991, 1992
   5  *
   6  *   This program is free software;  you can redistribute it and/or modify
   7  *   it under the terms of the GNU General Public License as published by
   8  *   the Free Software Foundation; either version 2 of the License, or
   9  *   (at your option) any later version.
  10  *
  11  *   This program is distributed in the hope that it will be useful,
  12  *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  14  *   the GNU General Public License for more details.
  15  *
  16  *   You should have received a copy of the GNU General Public License
  17  *   along with this program;  if not, write to the Free Software
  18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19  */
  20
  21 #include <linux/sched.h>
  22 #include <linux/slab.h>
  23 #include <linux/fs.h>
  24 #include <linux/posix_acl_xattr.h>
  25 #include "jfs_incore.h"
  26 #include "jfs_txnmgr.h"
  27 #include "jfs_xattr.h"
  28 #include "jfs_acl.h"
  29
  30 struct posix_acl *jfs_get_acl(struct inode *inode, int type)
  31 {
  32         struct posix_acl *acl;
  33         char *ea_name;
  34         int size;
  35         char *value = NULL;
  36
  37         switch(type) {
  38                 case ACL_TYPE_ACCESS:
  39                         ea_name = XATTR_NAME_POSIX_ACL_ACCESS;
  40                         break;
  41                 case ACL_TYPE_DEFAULT:
  42                         ea_name = XATTR_NAME_POSIX_ACL_DEFAULT;
  43                         break;
  44                 default:
  45                         return ERR_PTR(-EINVAL);
  46         }
  47
  48         size = __jfs_getxattr(inode, ea_name, NULL, 0);
  49
  50         if (size > 0) {
  51                 value = kmalloc(size, GFP_KERNEL);
  52                 if (!value)
  53                         return ERR_PTR(-ENOMEM);
  54                 size = __jfs_getxattr(inode, ea_name, value, size);
  55         }
  56
  57         if (size < 0) {
  58                 if (size == -ENODATA)
  59                         acl = NULL;
  60                 else
  61                         acl = ERR_PTR(size);
  62         } else {
  63                 acl = posix_acl_from_xattr(&init_user_ns, value, size);
  64         }
  65         kfree(value);
  66         return acl;
  67 }
  68
  69 static int __jfs_set_acl(tid_t tid, struct inode *inode, int type,
  70                        struct posix_acl *acl)
  71 {
  72         char *ea_name;
  73         int rc;
  74         int size = 0;
  75         char *value = NULL;
  76
  77         switch (type) {
  78         case ACL_TYPE_ACCESS:
  79                 ea_name = XATTR_NAME_POSIX_ACL_ACCESS;
  80                 if (acl) {
  81                         rc = posix_acl_update_mode(inode, &inode->i_mode, &acl);
  82                         if (rc)
  83                                 return rc;
  84                         inode->i_ctime = current_time(inode);
  85                         mark_inode_dirty(inode);
  86                 }
  87                 break;
  88         case ACL_TYPE_DEFAULT:
  89                 ea_name = XATTR_NAME_POSIX_ACL_DEFAULT;
  90                 break;
  91         default:
  92                 return -EINVAL;
  93         }
  94
  95         if (acl) {
  96                 size = posix_acl_xattr_size(acl->a_count);
  97                 value = kmalloc(size, GFP_KERNEL);
  98                 if (!value)
  99                         return -ENOMEM;
 100                 rc = posix_acl_to_xattr(&init_user_ns, acl, value, size);
 101                 if (rc < 0)
 102                         goto out;
 103         }
 104         rc = __jfs_setxattr(tid, inode, ea_name, value, size, 0);
 105 out:
 106         kfree(value);
 107
 108         if (!rc)
 109                 set_cached_acl(inode, type, acl);
 110
 111         return rc;
 112 }
 113
 114 int jfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
 115 {
 116         int rc;
 117         tid_t tid;
 118
 119         tid = txBegin(inode->i_sb, 0);
 120         mutex_lock(&JFS_IP(inode)->commit_mutex);
 121         rc = __jfs_set_acl(tid, inode, type, acl);
 122         if (!rc)
 123                 rc = txCommit(tid, 1, &inode, 0);
 124         txEnd(tid);
 125         mutex_unlock(&JFS_IP(inode)->commit_mutex);
 126         return rc;
 127 }
 128
 129 int jfs_init_acl(tid_t tid, struct inode *inode, struct inode *dir)
 130 {
 131         struct posix_acl *default_acl, *acl;
 132         int rc = 0;
 133
 134         rc = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
 135         if (rc)
 136                 return rc;
 137
 138         if (default_acl) {
 139                 rc = __jfs_set_acl(tid, inode, ACL_TYPE_DEFAULT, default_acl);
 140                 posix_acl_release(default_acl);
 141         }
 142
 143         if (acl) {
 144                 if (!rc)
 145                         rc = __jfs_set_acl(tid, inode, ACL_TYPE_ACCESS, acl);
 146                 posix_acl_release(acl);
 147         }
 148
 149         JFS_IP(inode)->mode2 = (JFS_IP(inode)->mode2 & 0xffff0000) |
 150                                inode->i_mode;
 151
 152         return rc;
 153 }