1 files changed, 17 insertions, 36 deletions

diff --git a/include/linux/mount.h b/include/linux/mount.h
index 5e7a59408dd4..1869ea24a739 100644
--- a/include/linux/mount.h
+++ b/include/linux/mount.h
@@ -13,6 +13,7 @@
 #include <linux/list.h>
 #include <linux/nodemask.h>
 #include <linux/spinlock.h>
+#include <linux/seqlock.h>
 #include <asm/atomic.h>
 
 struct super_block;
@@ -46,12 +47,24 @@ struct mnt_namespace;
 
 #define MNT_INTERNAL    0x4000
 
+struct mnt_pcp {
+        int mnt_count;
+        int mnt_writers;
+};
+
 struct vfsmount {
         struct list_head mnt_hash;
         struct vfsmount *mnt_parent;    /* fs we are mounted on */
         struct dentry *mnt_mountpoint;  /* dentry of mountpoint */
         struct dentry *mnt_root;        /* root of the mounted tree */
         struct super_block *mnt_sb;     /* pointer to superblock */
+#ifdef CONFIG_SMP
+        struct mnt_pcp __percpu *mnt_pcp;
+        atomic_t mnt_longrefs;
+#else
+        int mnt_count;
+        int mnt_writers;
+#endif
         struct list_head mnt_mounts;    /* list of children, anchored here */
         struct list_head mnt_child;     /* and going through their mnt_child */
         int mnt_flags;
@@ -70,57 +83,25 @@ struct vfsmount {
         struct mnt_namespace *mnt_ns;   /* containing namespace */
         int mnt_id;                     /* mount identifier */
         int mnt_group_id;               /* peer group identifier */
-        /*
-         * We put mnt_count & mnt_expiry_mark at the end of struct vfsmount
-         * to let these frequently modified fields in a separate cache line
-         * (so that reads of mnt_flags wont ping-pong on SMP machines)
-         */
-        atomic_t mnt_count;
         int mnt_expiry_mark;            /* true if marked for expiry */
         int mnt_pinned;
         int mnt_ghosts;
-#ifdef CONFIG_SMP
-        int __percpu *mnt_writers;
-#else
-        int mnt_writers;
-#endif
 };
 
-static inline int *get_mnt_writers_ptr(struct vfsmount *mnt)
-{
-#ifdef CONFIG_SMP
-        return mnt->mnt_writers;
-#else
-        return &mnt->mnt_writers;
-#endif
-}
-
-static inline struct vfsmount *mntget(struct vfsmount *mnt)
-{
-        if (mnt)
-                atomic_inc(&mnt->mnt_count);
-        return mnt;
-}
-
 struct file; /* forward dec */
 
 extern int mnt_want_write(struct vfsmount *mnt);
 extern int mnt_want_write_file(struct file *file);
 extern int mnt_clone_write(struct vfsmount *mnt);
 extern void mnt_drop_write(struct vfsmount *mnt);
-extern void mntput_no_expire(struct vfsmount *mnt);
+extern void mntput(struct vfsmount *mnt);
+extern struct vfsmount *mntget(struct vfsmount *mnt);
+extern void mntput_long(struct vfsmount *mnt);
+extern struct vfsmount *mntget_long(struct vfsmount *mnt);
 extern void mnt_pin(struct vfsmount *mnt);
 extern void mnt_unpin(struct vfsmount *mnt);
 extern int __mnt_is_readonly(struct vfsmount *mnt);
 
-static inline void mntput(struct vfsmount *mnt)
-{
-        if (mnt) {
-                mnt->mnt_expiry_mark = 0;
-                mntput_no_expire(mnt);
-        }
-}
-
 extern struct vfsmount *do_kern_mount(const char *fstype, int flags,
                                       const char *name, void *data);