1 files changed, 25 insertions, 13 deletions

diff --git a/fs/namespace.c b/fs/namespace.c
index a7bea8c8bd46..277c28a63ead 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -22,6 +22,7 @@
 #include <linux/seq_file.h>
 #include <linux/mnt_namespace.h>
 #include <linux/namei.h>
+#include <linux/nsproxy.h>
 #include <linux/security.h>
 #include <linux/mount.h>
 #include <linux/ramfs.h>
@@ -42,6 +43,8 @@ __cacheline_aligned_in_smp DEFINE_SPINLOCK(vfsmount_lock);
 static int event;
 static DEFINE_IDA(mnt_id_ida);
 static DEFINE_IDA(mnt_group_ida);
+static int mnt_id_start = 0;
+static int mnt_group_start = 1;
 
 static struct list_head *mount_hashtable __read_mostly;
 static struct kmem_cache *mnt_cache __read_mostly;
@@ -69,7 +72,9 @@ static int mnt_alloc_id(struct vfsmount *mnt)
 retry:
         ida_pre_get(&mnt_id_ida, GFP_KERNEL);
         spin_lock(&vfsmount_lock);
-        res = ida_get_new(&mnt_id_ida, &mnt->mnt_id);
+        res = ida_get_new_above(&mnt_id_ida, mnt_id_start, &mnt->mnt_id);
+        if (!res)
+                mnt_id_start = mnt->mnt_id + 1;
         spin_unlock(&vfsmount_lock);
         if (res == -EAGAIN)
                 goto retry;
@@ -79,8 +84,11 @@ retry:
 
 static void mnt_free_id(struct vfsmount *mnt)
 {
+        int id = mnt->mnt_id;
         spin_lock(&vfsmount_lock);
-        ida_remove(&mnt_id_ida, mnt->mnt_id);
+        ida_remove(&mnt_id_ida, id);
+        if (mnt_id_start > id)
+                mnt_id_start = id;
         spin_unlock(&vfsmount_lock);
 }
 
@@ -91,10 +99,18 @@ static void mnt_free_id(struct vfsmount *mnt)
  */
 static int mnt_alloc_group_id(struct vfsmount *mnt)
 {
+        int res;
+
         if (!ida_pre_get(&mnt_group_ida, GFP_KERNEL))
                 return -ENOMEM;
 
-        return ida_get_new_above(&mnt_group_ida, 1, &mnt->mnt_group_id);
+        res = ida_get_new_above(&mnt_group_ida,
+                                mnt_group_start,
+                                &mnt->mnt_group_id);
+        if (!res)
+                mnt_group_start = mnt->mnt_group_id + 1;
+
+        return res;
 }
 
 /*
@@ -102,7 +118,10 @@ static int mnt_alloc_group_id(struct vfsmount *mnt)
  */
 void mnt_release_group_id(struct vfsmount *mnt)
 {
-        ida_remove(&mnt_group_ida, mnt->mnt_group_id);
+        int id = mnt->mnt_group_id;
+        ida_remove(&mnt_group_ida, id);
+        if (mnt_group_start > id)
+                mnt_group_start = id;
         mnt->mnt_group_id = 0;
 }
 
@@ -2222,16 +2241,9 @@ static void __init init_mount_tree(void)
         mnt = do_kern_mount("rootfs", 0, "rootfs", NULL);
         if (IS_ERR(mnt))
                 panic("Can't create rootfs");
-        ns = kmalloc(sizeof(*ns), GFP_KERNEL);
-        if (!ns)
+        ns = create_mnt_ns(mnt);
+        if (IS_ERR(ns))
                 panic("Can't allocate initial namespace");
-        atomic_set(&ns->count, 1);
-        INIT_LIST_HEAD(&ns->list);
-        init_waitqueue_head(&ns->poll);
-        ns->event = 0;
-        list_add(&mnt->mnt_list, &ns->list);
-        ns->root = mnt;
-        mnt->mnt_ns = ns;
 
         init_task.nsproxy->mnt_ns = ns;
         get_mnt_ns(ns);