lockd: stop abusing file_lock_list

Currently lockd directly access the file_lock_list from fs/locks.c.
It does so to mark locks granted or reclaimable.  This is very
suboptimal, because a) lockd needs to poke into locks.c internals, and
b) it needs to iterate over all locks in the system for marking locks
granted or reclaimable.

This patch adds lists for granted and reclaimable locks to the nlm_host
structure instead, and adds locks to those.

nlmclnt_lock:
	now adds the lock to h_granted instead of setting the
	NFS_LCK_GRANTED, still O(1)

nlmclnt_mark_reclaim:
	goes away completely, replaced by a list_splice_init.
	Complexity reduced from O(locks in the system) to O(1)

reclaimer:
	iterates over h_reclaim now, complexity reduced from
	O(locks in the system) to O(locks per nlm_host)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/include/linux/nfs_fs_i.h b/include/linux/nfs_fs_i.h
index e2c18dab..8617302 100644
--- a/include/linux/nfs_fs_i.h
+++ b/include/linux/nfs_fs_i.h
@@ -12,8 +12,8 @@
  */
 struct nfs_lock_info {
 	u32		state;
-	u32		flags;
 	struct nlm_lockowner *owner;
+	struct list_head list;
 };
 
 struct nfs4_lock_state;
@@ -21,10 +21,4 @@
 	struct nfs4_lock_state *owner;
 };
 
-/*
- * Lock flag values
- */
-#define NFS_LCK_GRANTED		0x0001		/* lock has been granted */
-#define NFS_LCK_RECLAIM		0x0002		/* lock marked for reclaiming */
-
 #endif