Btrfs: fix /proc/mounts info.

Some mount options are not displayed by /proc/mounts.
This patch displays the option such as compress_type by /proc/mounts.

Ex.
  [before]
    $ mount | grep sdc2
    /dev/sdc2 on /test12 type btrfs (rw,space_cache,compress=lzo)
    $ cat /proc/mounts | grep sdc2
    /dev/sdc2 /test12 btrfs rw,relatime,compress 0 0

  [after]
    $ mount | grep sdc2
    /dev/sdc2 on /test12 type btrfs (rw,space_cache,compress=lzo)
    $ cat /proc/mounts | grep sdc2
    /dev/sdc2 /test12 btrfs rw,relatime,compress=lzo,space_cache 0 0

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 17 insertions, 2 deletions

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 2edfc039f09..58e7de9cc90 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -644,6 +644,7 @@ static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
 {
         struct btrfs_root *root = btrfs_sb(vfs->mnt_sb);
         struct btrfs_fs_info *info = root->fs_info;
+        char *compress_type;
 
         if (btrfs_test_opt(root, DEGRADED))
                 seq_puts(seq, ",degraded");
@@ -662,8 +663,16 @@ static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
         if (info->thread_pool_size !=  min_t(unsigned long,
                                              num_online_cpus() + 2, 8))
                 seq_printf(seq, ",thread_pool=%d", info->thread_pool_size);
-        if (btrfs_test_opt(root, COMPRESS))
-                seq_puts(seq, ",compress");
+        if (btrfs_test_opt(root, COMPRESS)) {
+                if (info->compress_type == BTRFS_COMPRESS_ZLIB)
+                        compress_type = "zlib";
+                else
+                        compress_type = "lzo";
+                if (btrfs_test_opt(root, FORCE_COMPRESS))
+                        seq_printf(seq, ",compress-force=%s", compress_type);
+                else
+                        seq_printf(seq, ",compress=%s", compress_type);
+        }
         if (btrfs_test_opt(root, NOSSD))
                 seq_puts(seq, ",nossd");
         if (btrfs_test_opt(root, SSD_SPREAD))
@@ -678,6 +687,12 @@ static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
                 seq_puts(seq, ",discard");
         if (!(root->fs_info->sb->s_flags & MS_POSIXACL))
                 seq_puts(seq, ",noacl");
+        if (btrfs_test_opt(root, SPACE_CACHE))
+                seq_puts(seq, ",space_cache");
+        if (btrfs_test_opt(root, CLEAR_CACHE))
+                seq_puts(seq, ",clear_cache");
+        if (btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
+                seq_puts(seq, ",user_subvol_rm_allowed");
         return 0;
 }