1 files changed, 44 insertions, 6 deletions

diff --git a/fs/namespace.c b/fs/namespace.c
index 39c81a8d6316..bf478addb852 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -43,9 +43,9 @@ __cacheline_aligned_in_smp DEFINE_SPINLOCK(vfsmount_lock);
 
 static int event;
 
-static struct list_head *mount_hashtable;
+static struct list_head *mount_hashtable __read_mostly;
 static int hash_mask __read_mostly, hash_bits __read_mostly;
-static kmem_cache_t *mnt_cache;
+static kmem_cache_t *mnt_cache __read_mostly;
 static struct rw_semaphore namespace_sem;
 
 /* /sys/fs */
@@ -399,6 +399,44 @@ struct seq_operations mounts_op = {
         .show   = show_vfsmnt
 };
 
+static int show_vfsstat(struct seq_file *m, void *v)
+{
+        struct vfsmount *mnt = v;
+        int err = 0;
+
+        /* device */
+        if (mnt->mnt_devname) {
+                seq_puts(m, "device ");
+                mangle(m, mnt->mnt_devname);
+        } else
+                seq_puts(m, "no device");
+
+        /* mount point */
+        seq_puts(m, " mounted on ");
+        seq_path(m, mnt, mnt->mnt_root, " \t\n\\");
+        seq_putc(m, ' ');
+
+        /* file system type */
+        seq_puts(m, "with fstype ");
+        mangle(m, mnt->mnt_sb->s_type->name);
+
+        /* optional statistics */
+        if (mnt->mnt_sb->s_op->show_stats) {
+                seq_putc(m, ' ');
+                err = mnt->mnt_sb->s_op->show_stats(m, mnt);
+        }
+
+        seq_putc(m, '\n');
+        return err;
+}
+
+struct seq_operations mountstats_op = {
+        .start  = m_start,
+        .next   = m_next,
+        .stop   = m_stop,
+        .show   = show_vfsstat,
+};
+
 /**
  * may_umount_tree - check if a mount tree is busy
  * @mnt: root of mount tree
@@ -421,9 +459,9 @@ int may_umount_tree(struct vfsmount *mnt)
         spin_unlock(&vfsmount_lock);
 
         if (actual_refs > minimum_refs)
-                return -EBUSY;
+                return 0;
 
-        return 0;
+        return 1;
 }
 
 EXPORT_SYMBOL(may_umount_tree);
@@ -443,10 +481,10 @@ EXPORT_SYMBOL(may_umount_tree);
  */
 int may_umount(struct vfsmount *mnt)
 {
-        int ret = 0;
+        int ret = 1;
         spin_lock(&vfsmount_lock);
         if (propagate_mount_busy(mnt, 2))
-                ret = -EBUSY;
+                ret = 0;
         spin_unlock(&vfsmount_lock);
         return ret;
 }