fs/jfs/ioctl.c

   1 /*
   2  * linux/fs/jfs/ioctl.c
   3  *
   4  * Copyright (C) 2006 Herbert Poetzl
   5  * adapted from Remy Card's ext2/ioctl.c
   6  */
   7
   8 #include <linux/fs.h>
   9 #include <linux/ext2_fs.h>
  10 #include <linux/ctype.h>
  11 #include <linux/capability.h>
  12 #include <linux/time.h>
  13 #include <asm/current.h>
  14 #include <asm/uaccess.h>
  15
  16 #include "jfs_incore.h"
  17 #include "jfs_dinode.h"
  18 #include "jfs_inode.h"
  19
  20
  21 static struct {
  22         long jfs_flag;
  23         long ext2_flag;
  24 } jfs_map[] = {
  25         {JFS_NOATIME_FL, EXT2_NOATIME_FL},
  26         {JFS_DIRSYNC_FL, EXT2_DIRSYNC_FL},
  27         {JFS_SYNC_FL, EXT2_SYNC_FL},
  28         {JFS_SECRM_FL, EXT2_SECRM_FL},
  29         {JFS_UNRM_FL, EXT2_UNRM_FL},
  30         {JFS_APPEND_FL, EXT2_APPEND_FL},
  31         {JFS_IMMUTABLE_FL, EXT2_IMMUTABLE_FL},
  32         {0, 0},
  33 };
  34
  35 static long jfs_map_ext2(unsigned long flags, int from)
  36 {
  37         int index=0;
  38         long mapped=0;
  39
  40         while (jfs_map[index].jfs_flag) {
  41                 if (from) {
  42                         if (jfs_map[index].ext2_flag & flags)
  43                                 mapped |= jfs_map[index].jfs_flag;
  44                 } else {
  45                         if (jfs_map[index].jfs_flag & flags)
  46                                 mapped |= jfs_map[index].ext2_flag;
  47                 }
  48                 index++;
  49         }
  50         return mapped;
  51 }
  52
  53
  54 int jfs_ioctl(struct inode * inode, struct file * filp, unsigned int cmd,
  55                 unsigned long arg)
  56 {
  57         struct jfs_inode_info *jfs_inode = JFS_IP(inode);
  58         unsigned int flags;
  59
  60         switch (cmd) {
  61         case JFS_IOC_GETFLAGS:
  62                 flags = jfs_inode->mode2 & JFS_FL_USER_VISIBLE;
  63                 flags = jfs_map_ext2(flags, 0);
  64                 return put_user(flags, (int __user *) arg);
  65         case JFS_IOC_SETFLAGS: {
  66                 unsigned int oldflags;
  67
  68                 if (IS_RDONLY(inode))
  69                         return -EROFS;
  70
  71                 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
  72                         return -EACCES;
  73
  74                 if (get_user(flags, (int __user *) arg))
  75                         return -EFAULT;
  76
  77                 flags = jfs_map_ext2(flags, 1);
  78                 if (!S_ISDIR(inode->i_mode))
  79                         flags &= ~JFS_DIRSYNC_FL;
  80
  81                 oldflags = jfs_inode->mode2;
  82
  83                 /*
  84                  * The IMMUTABLE and APPEND_ONLY flags can only be changed by
  85                  * the relevant capability.
  86                  */
  87                 if ((oldflags & JFS_IMMUTABLE_FL) ||
  88                         ((flags ^ oldflags) &
  89                         (JFS_APPEND_FL | JFS_IMMUTABLE_FL))) {
  90                         if (!capable(CAP_LINUX_IMMUTABLE))
  91                                 return -EPERM;
  92                 }
  93
  94                 flags = flags & JFS_FL_USER_MODIFIABLE;
  95                 flags |= oldflags & ~JFS_FL_USER_MODIFIABLE;
  96                 jfs_inode->mode2 = flags;
  97
  98                 jfs_set_inode_flags(inode);
  99                 inode->i_ctime = CURRENT_TIME_SEC;
 100                 mark_inode_dirty(inode);
 101                 return 0;
 102         }
 103         default:
 104                 return -ENOTTY;
 105         }
 106 }
 107