xfs: remove i_iocount

We now have an i_dio_count filed and surrounding infrastructure to wait
for direct I/O completion instead of i_icount, and we have never needed
to iocount waits for buffered I/O given that we only set the page uptodate
after finishing all required work.  Thus remove i_iocount, and replace
the actually needed waits with calls to inode_dio_wait.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>


diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index e1ff077..46bba3e 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -38,40 +38,6 @@
 #include <linux/pagevec.h>
 #include <linux/writeback.h>
 
-
-/*
- * Prime number of hash buckets since address is used as the key.
- */
-#define NVSYNC		37
-#define to_ioend_wq(v)	(&xfs_ioend_wq[((unsigned long)v) % NVSYNC])
-static wait_queue_head_t xfs_ioend_wq[NVSYNC];
-
-void __init
-xfs_ioend_init(void)
-{
-	int i;
-
-	for (i = 0; i < NVSYNC; i++)
-		init_waitqueue_head(&xfs_ioend_wq[i]);
-}
-
-void
-xfs_ioend_wait(
-	xfs_inode_t	*ip)
-{
-	wait_queue_head_t *wq = to_ioend_wq(ip);
-
-	wait_event(*wq, (atomic_read(&ip->i_iocount) == 0));
-}
-
-STATIC void
-xfs_ioend_wake(
-	xfs_inode_t	*ip)
-{
-	if (atomic_dec_and_test(&ip->i_iocount))
-		wake_up(to_ioend_wq(ip));
-}
-
 void
 xfs_count_page_state(
 	struct page		*page,
@@ -115,7 +81,6 @@
 	xfs_ioend_t		*ioend)
 {
 	struct buffer_head	*bh, *next;
-	struct xfs_inode	*ip = XFS_I(ioend->io_inode);
 
 	for (bh = ioend->io_buffer_head; bh; bh = next) {
 		next = bh->b_private;
@@ -127,7 +92,7 @@
 			aio_complete(ioend->io_iocb, ioend->io_result, 0);
 		inode_dio_done(ioend->io_inode);
 	}
-	xfs_ioend_wake(ip);
+
 	mempool_free(ioend, xfs_ioend_pool);
 }
 
@@ -298,7 +263,6 @@
 	ioend->io_inode = inode;
 	ioend->io_buffer_head = NULL;
 	ioend->io_buffer_tail = NULL;
-	atomic_inc(&XFS_I(ioend->io_inode)->i_iocount);
 	ioend->io_offset = 0;
 	ioend->io_size = 0;
 	ioend->io_iocb = NULL;
@@ -558,7 +522,6 @@
 			unlock_buffer(bh);
 		} while ((bh = next_bh) != NULL);
 
-		xfs_ioend_wake(XFS_I(ioend->io_inode));
 		mempool_free(ioend, xfs_ioend_pool);
 	} while ((ioend = next) != NULL);
 }