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                 break;
  81         case ACL_TYPE_DEFAULT:
  82                 ea_name = XATTR_NAME_POSIX_ACL_DEFAULT;
  83                 break;
  84         default:
  85                 return -EINVAL;
  86         }
  87
  88         if (acl) {
  89                 size = posix_acl_xattr_size(acl->a_count);
  90                 value = kmalloc(size, GFP_KERNEL);
  91                 if (!value)
  92                         return -ENOMEM;
  93                 rc = posix_acl_to_xattr(&init_user_ns, acl, value, size);
  94                 if (rc < 0)
  95                         goto out;
  96         }
  97         rc = __jfs_setxattr(tid, inode, ea_name, value, size, 0);
  98 out:
  99         kfree(value);
 100
 101         if (!rc)
 102                 set_cached_acl(inode, type, acl);
 103
 104         return rc;
 105 }
 106
 107 int jfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
 108 {
 109         int rc;
 110         tid_t tid;
 111         int update_mode = 0;
 112         umode_t mode = inode->i_mode;
 113
 114         tid = txBegin(inode->i_sb, 0);
 115         mutex_lock(&JFS_IP(inode)->commit_mutex);
 116         if (type == ACL_TYPE_ACCESS && acl) {
 117                 rc = posix_acl_update_mode(inode, &mode, &acl);
 118                 if (rc)
 119                         goto end_tx;
 120                 update_mode = 1;
 121         }
 122         rc = __jfs_set_acl(tid, inode, type, acl);
 123         if (!rc) {
 124                 if (update_mode) {
 125                         inode->i_mode = mode;
 126                         inode->i_ctime = current_time(inode);
 127                         mark_inode_dirty(inode);
 128                 }
 129                 rc = txCommit(tid, 1, &inode, 0);
 130         }
 131 end_tx:
 132         txEnd(tid);
 133         mutex_unlock(&JFS_IP(inode)->commit_mutex);
 134         return rc;
 135 }
 136
 137 int jfs_init_acl(tid_t tid, struct inode *inode, struct inode *dir)
 138 {
 139         struct posix_acl *default_acl, *acl;
 140         int rc = 0;
 141
 142         rc = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
 143         if (rc)
 144                 return rc;
 145
 146         if (default_acl) {
 147                 rc = __jfs_set_acl(tid, inode, ACL_TYPE_DEFAULT, default_acl);
 148                 posix_acl_release(default_acl);
 149         }
 150
 151         if (acl) {
 152                 if (!rc)
 153                         rc = __jfs_set_acl(tid, inode, ACL_TYPE_ACCESS, acl);
 154                 posix_acl_release(acl);
 155         }
 156
 157         JFS_IP(inode)->mode2 = (JFS_IP(inode)->mode2 & 0xffff0000) |
 158                                inode->i_mode;
 159
 160         return rc;
 161 }