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