releases/4.6.1/hpfs-implement-the-show_options-method.patch

   1 From 037369b872940cd923835a0a589763180c4a36bc Mon Sep 17 00:00:00 2001
   2 From: Mikulas Patocka <mikulas@twibright.com>
   3 Date: Tue, 24 May 2016 22:49:18 +0200
   4 Subject: hpfs: implement the show_options method
   5
   6 From: Mikulas Patocka <mikulas@twibright.com>
   7
   8 commit 037369b872940cd923835a0a589763180c4a36bc upstream.
   9
  10 The HPFS filesystem used generic_show_options to produce string that is
  11 displayed in /proc/mounts.  However, there is a problem that the options
  12 may disappear after remount.  If we mount the filesystem with option1
  13 and then remount it with option2, /proc/mounts should show both option1
  14 and option2, however it only shows option2 because the whole option
  15 string is replaced with replace_mount_options in hpfs_remount_fs.
  16
  17 To fix this bug, implement the hpfs_show_options function that prints
  18 options that are currently selected.
  19
  20 Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
  21 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
  22 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  23
  24 ---
  25  fs/hpfs/super.c |   43 ++++++++++++++++++++++++++++++++-----------
  26  1 file changed, 32 insertions(+), 11 deletions(-)
  27
  28 --- a/fs/hpfs/super.c
  29 +++ b/fs/hpfs/super.c
  30 @@ -15,6 +15,7 @@
  31  #include <linux/sched.h>
  32  #include <linux/bitmap.h>
  33  #include <linux/slab.h>
  34 +#include <linux/seq_file.h>
  35
  36  /* Mark the filesystem dirty, so that chkdsk checks it when os/2 booted */
  37
  38 @@ -453,10 +454,6 @@ static int hpfs_remount_fs(struct super_
  39         int lowercase, eas, chk, errs, chkdsk, timeshift;
  40         int o;
  41         struct hpfs_sb_info *sbi = hpfs_sb(s);
  42 -       char *new_opts = kstrdup(data, GFP_KERNEL);
  43 -
  44 -       if (data && !new_opts)
  45 -               return -ENOMEM;
  46
  47         sync_filesystem(s);
  48
  49 @@ -493,18 +490,44 @@ static int hpfs_remount_fs(struct super_
  50
  51         if (!(*flags & MS_RDONLY)) mark_dirty(s, 1);
  52
  53 -       if (new_opts)
  54 -               replace_mount_options(s, new_opts);
  55 -
  56         hpfs_unlock(s);
  57         return 0;
  58
  59  out_err:
  60         hpfs_unlock(s);
  61 -       kfree(new_opts);
  62         return -EINVAL;
  63  }
  64
  65 +static int hpfs_show_options(struct seq_file *seq, struct dentry *root)
  66 +{
  67 +       struct hpfs_sb_info *sbi = hpfs_sb(root->d_sb);
  68 +
  69 +       seq_printf(seq, ",uid=%u", from_kuid_munged(&init_user_ns, sbi->sb_uid));
  70 +       seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, sbi->sb_gid));
  71 +       seq_printf(seq, ",umask=%03o", (~sbi->sb_mode & 0777));
  72 +       if (sbi->sb_lowercase)
  73 +               seq_printf(seq, ",case=lower");
  74 +       if (!sbi->sb_chk)
  75 +               seq_printf(seq, ",check=none");
  76 +       if (sbi->sb_chk == 2)
  77 +               seq_printf(seq, ",check=strict");
  78 +       if (!sbi->sb_err)
  79 +               seq_printf(seq, ",errors=continue");
  80 +       if (sbi->sb_err == 2)
  81 +               seq_printf(seq, ",errors=panic");
  82 +       if (!sbi->sb_chkdsk)
  83 +               seq_printf(seq, ",chkdsk=no");
  84 +       if (sbi->sb_chkdsk == 2)
  85 +               seq_printf(seq, ",chkdsk=always");
  86 +       if (!sbi->sb_eas)
  87 +               seq_printf(seq, ",eas=no");
  88 +       if (sbi->sb_eas == 1)
  89 +               seq_printf(seq, ",eas=ro");
  90 +       if (sbi->sb_timeshift)
  91 +               seq_printf(seq, ",timeshift=%d", sbi->sb_timeshift);
  92 +       return 0;
  93 +}
  94 +
  95  /* Super operations */
  96
  97  static const struct super_operations hpfs_sops =
  98 @@ -515,7 +538,7 @@ static const struct super_operations hpf
  99         .put_super      = hpfs_put_super,
 100         .statfs         = hpfs_statfs,
 101         .remount_fs     = hpfs_remount_fs,
 102 -       .show_options   = generic_show_options,
 103 +       .show_options   = hpfs_show_options,
 104  };
 105
 106  static int hpfs_fill_super(struct super_block *s, void *options, int silent)
 107 @@ -538,8 +561,6 @@ static int hpfs_fill_super(struct super_
 108
 109         int o;
 110
 111 -       save_mount_options(s, options);
 112 -
 113         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 114         if (!sbi) {
 115                 return -ENOMEM;