[PATCH 4.6 097/100] hpfs: implement the show_options method

Greg Kroah-Hartman
2016-05-30T20:50:32Z

From: Mikulas Patocka <mikulas@twibright.com>

commit 037369b872940cd923835a0a589763180c4a36bc upstream.

The HPFS filesystem used generic_show_options to produce string that is
displayed in /proc/mounts. However, there is a problem that the options
may disappear after remount. If we mount the filesystem with option1
and then remount it with option2, /proc/mounts should show both option1
and option2, however it only shows option2 because the whole option
string is replaced with replace_mount_options in hpfs_remount_fs.

To fix this bug, implement the hpfs_show_options function that prints
options that are currently selected.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/hpfs/super.c | 43 ++++++++++++++++++++++++++++++++-----------
1 file changed, 32 insertions(+), 11 deletions(-)

--- a/fs/hpfs/super.c
+++ b/fs/hpfs/super.c
@@ -15,6 +15,7 @@
#include <linux/sched.h>
#include <linux/bitmap.h>
#include <linux/slab.h>
+#include <linux/seq_file.h>

/* Mark the filesystem dirty, so that chkdsk checks it when os/2 booted */

@@ -453,10 +454,6 @@ static int hpfs_remount_fs(struct super_
int lowercase, eas, chk, errs, chkdsk, timeshift;
int o;
struct hpfs_sb_info *sbi = hpfs_sb(s);
- char *new_opts = kstrdup(data, GFP_KERNEL);
-
- if (data && !new_opts)
- return -ENOMEM;

sync_filesystem(s);

@@ -493,18 +490,44 @@ static int hpfs_remount_fs(struct super_

if (!(*flags & MS_RDONLY)) mark_dirty(s, 1);

- if (new_opts)
- replace_mount_options(s, new_opts);
-
hpfs_unlock(s);
return 0;

out_err:
hpfs_unlock(s);
- kfree(new_opts);
return -EINVAL;
}

+static int hpfs_show_options(struct seq_file *seq, struct dentry *root)
+{
+ struct hpfs_sb_info *sbi = hpfs_sb(root->d_sb);
+
+ seq_printf(seq, ",uid=%u", from_kuid_munged(&init_user_ns, sbi->sb_uid));
+ seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, sbi->sb_gid));
+ seq_printf(seq, ",umask=%03o", (~sbi->sb_mode & 0777));
+ if (sbi->sb_lowercase)
+ seq_printf(seq, ",case=lower");
+ if (!sbi->sb_chk)
+ seq_printf(seq, ",check=none");
+ if (sbi->sb_chk == 2)
+ seq_printf(seq, ",check=strict");
+ if (!sbi->sb_err)
+ seq_printf(seq, ",errors=continue");
+ if (sbi->sb_err == 2)
+ seq_printf(seq, ",errors=panic");
+ if (!sbi->sb_chkdsk)
+ seq_printf(seq, ",chkdsk=no");
+ if (sbi->sb_chkdsk == 2)
+ seq_printf(seq, ",chkdsk=always");
+ if (!sbi->sb_eas)
+ seq_printf(seq, ",eas=no");
+ if (sbi->sb_eas == 1)
+ seq_printf(seq, ",eas=ro");
+ if (sbi->sb_timeshift)
+ seq_printf(seq, ",timeshift=%d", sbi->sb_timeshift);
+ return 0;
+}
+
/* Super operations */

static const struct super_operations hpfs_sops =
@@ -515,7 +538,7 @@ static const struct super_operations hpf
.put_super = hpfs_put_super,
.statfs = hpfs_statfs,
.remount_fs = hpfs_remount_fs,
- .show_options = generic_show_options,
+ .show_options = hpfs_show_options,
};

static int hpfs_fill_super(struct super_block *s, void *options, int silent)
@@ -538,8 +561,6 @@ static int hpfs_fill_super(struct super_

int o;

- save_mount_options(s, options);
-
sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
if (!sbi) {
return -ENOMEM;