[XFS] Remove a no-longer-used pagebuf source file.

fs/xfs/pagebuf/page_buf_locking.c

-/*
- * Copyright (c) 2000-2002 Silicon Graphics, Inc.  All Rights Reserved.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of version 2 of the GNU General Public License as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it would be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
- *
- * Further, this software is distributed without any warranty that it is
- * free of the rightful claim of any third person regarding infringement
- * or the like.  Any license provided herein, whether implied or
- * otherwise, applies only to this software file.  Patent licenses, if
- * any, provided herein do not apply to combinations of this program with
- * other software, or any other product whatsoever.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write the Free Software Foundation, Inc., 59
- * Temple Place - Suite 330, Boston MA 02111-1307, USA.
- *
- * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
- * Mountain View, CA  94043, or:
- *
- * http://www.sgi.com
- *
- * For further information regarding this notice, see:
- *
- * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
- */
-
-/*
- *	page_buf_locking.c
- *
- *	The page_buf module provides an abstract buffer cache model on top of
- *	the Linux page cache.  Cached metadata blocks for a file system are
- *	hashed to the inode for the block device.  The page_buf module
- *	assembles buffer (page_buf_t) objects on demand to aggregate such
- *	cached pages for I/O.  The page_buf_locking module adds support for
- *	locking such page buffers.
- *
- *      Written by Steve Lord at SGI
- *
- */
-
-#include <linux/stddef.h>
-#include <linux/errno.h>
-#include <linux/slab.h>
-#include <linux/bitops.h>
-#include <linux/string.h>
-#include <linux/pagemap.h>
-#include <linux/init.h>
-#include <linux/major.h>
-
-#include <support/debug.h>
-
-#include "page_buf_internal.h"
-
-/*
- *	pagebuf_cond_lock
- *
- *	pagebuf_cond_lock locks a buffer object, if it is not already locked.
- *	Note that this in no way
- *	locks the underlying pages, so it is only useful for synchronizing
- *	concurrent use of page buffer objects, not for synchronizing independent
- *	access to the underlying pages.
- */
-int
-pagebuf_cond_lock(			/* lock buffer, if not locked	*/
-					/* returns -EBUSY if locked)	*/
-	page_buf_t		*pb)
-{
-	int			locked;
-
-	ASSERT(pb->pb_flags & _PBF_LOCKABLE);
-
-	locked = down_trylock(&pb->pb_sema) == 0;
-	if (locked) {
-		PB_SET_OWNER(pb);
-	}
-
-	PB_TRACE(pb, PB_TRACE_REC(condlck), locked);
-
-	return(locked ? 0 : -EBUSY);
-}
-
-/*
- *	pagebuf_lock_value
- *
- *	Return lock value for a pagebuf
- */
-int
-pagebuf_lock_value(
-	page_buf_t		*pb)
-{
-	ASSERT(pb->pb_flags & _PBF_LOCKABLE);
-	return(atomic_read(&pb->pb_sema.count));
-}
-
-/*
- *	pagebuf_lock
- *
- *	pagebuf_lock locks a buffer object.  Note that this in no way
- *	locks the underlying pages, so it is only useful for synchronizing
- *	concurrent use of page buffer objects, not for synchronizing independent
- *	access to the underlying pages.
- */
-int
-pagebuf_lock(
-	page_buf_t		*pb)
-{
-	ASSERT(pb->pb_flags & _PBF_LOCKABLE);
-
-	PB_TRACE(pb, PB_TRACE_REC(lock), 0);
-	if (atomic_read(&pb->pb_io_remaining))
-		blk_run_queues();
-	down(&pb->pb_sema);
-	PB_SET_OWNER(pb);
-	PB_TRACE(pb, PB_TRACE_REC(locked), 0);
-	return 0;
-}
-
-/*
- *	pagebuf_unlock
- *
- *	pagebuf_unlock releases the lock on the buffer object created by
- *	pagebuf_lock or pagebuf_cond_lock (not any
- *	pinning of underlying pages created by pagebuf_pin).
- */
-void
-pagebuf_unlock(				/* unlock buffer		*/
-	page_buf_t		*pb)	/* buffer to unlock		*/
-{
-	ASSERT(pb->pb_flags & _PBF_LOCKABLE);
-	PB_CLEAR_OWNER(pb);
-	up(&pb->pb_sema);
-	PB_TRACE(pb, PB_TRACE_REC(unlock), 0);
-}