1 files changed, 13 insertions, 2 deletions

diff --git a/include/linux/mount.h b/include/linux/mount.h
index 5ee2df217cdf..b4836d58f428 100644
--- a/include/linux/mount.h
+++ b/include/linux/mount.h
@@ -14,6 +14,7 @@
 
 #include <linux/types.h>
 #include <linux/list.h>
+#include <linux/nodemask.h>
 #include <linux/spinlock.h>
 #include <asm/atomic.h>
 
@@ -28,8 +29,10 @@ struct mnt_namespace;
 #define MNT_NOATIME     0x08
 #define MNT_NODIRATIME  0x10
 #define MNT_RELATIME    0x20
+#define MNT_READONLY    0x40    /* does the user want this to be r/o? */
 
 #define MNT_SHRINKABLE  0x100
+#define MNT_IMBALANCED_WRITE_COUNT      0x200 /* just for debugging */
 
 #define MNT_SHARED      0x1000  /* if the vfsmount is a shared mount */
 #define MNT_UNBINDABLE  0x2000  /* if the vfsmount is a unbindable mount */
@@ -53,6 +56,8 @@ struct vfsmount {
         struct list_head mnt_slave;     /* slave list entry */
         struct vfsmount *mnt_master;    /* slave is on master->mnt_slave_list */
         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
@@ -62,6 +67,11 @@ struct vfsmount {
         int mnt_expiry_mark;            /* true if marked for expiry */
         int mnt_pinned;
         int mnt_ghosts;
+        /*
+         * This value is not stable unless all of the mnt_writers[] spinlocks
+         * are held, and all mnt_writer[]s on this mount have 0 as their ->count
+         */
+        atomic_t __mnt_writers;
 };
 
 static inline struct vfsmount *mntget(struct vfsmount *mnt)
@@ -71,9 +81,12 @@ static inline struct vfsmount *mntget(struct vfsmount *mnt)
         return mnt;
 }
 
+extern int mnt_want_write(struct vfsmount *mnt);
+extern void mnt_drop_write(struct vfsmount *mnt);
 extern void mntput_no_expire(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)
 {
@@ -83,8 +96,6 @@ static inline void mntput(struct vfsmount *mnt)
         }
 }
 
-extern void free_vfsmnt(struct vfsmount *mnt);
-extern struct vfsmount *alloc_vfsmnt(const char *name);
 extern struct vfsmount *do_kern_mount(const char *fstype, int flags,
                                       const char *name, void *data);