From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with ESMTP id 4ED7C6B0204 for ; Thu, 22 Apr 2010 09:44:32 -0400 (EDT) Date: Thu, 22 Apr 2010 06:43:09 -0700 From: Dan Magenheimer Subject: Frontswap [PATCH 1/4] (was Transcendent Memory): swap data structure changes Message-ID: <20100422134309.GA2994@ca-server1.us.oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: owner-linux-mm@kvack.org To: linux-kernel@vger.kernel.org, linux-mm@kvack.org, jeremy@goop.org, hugh.dickins@tiscali.co.uk, ngupta@vflare.org, JBeulich@novell.com, chris.mason@oracle.com, kurt.hackel@oracle.com, dave.mccracken@oracle.com, npiggin@suse.de, akpm@linux-foundation.org, riel@redhat.com List-ID: Frontswap [PATCH 1/4] (was Transcendent Memory): swap data structure changes Core swap data structures are needed by frontswap.c but we don't need to expose them to the dozens of files that include swap.h so create a new swapfile.h just to extern-ify these. Add frontswap-related elements to swap_info_struct. Don't tie these to CONFIG_FRONTSWAP to avoid unnecessary clutter around various frontswap hooks. Signed-off-by: Dan Magenheimer Diffstat: swap.h | 2 ++ swapfile.h | 13 +++++++++++++ 2 files changed, 15 insertions(+) --- linux-2.6.34-rc5/include/linux/swapfile.h 1969-12-31 17:00:00.000000000 -0700 +++ linux-2.6.34-rc5-frontswap/include/linux/swapfile.h 2010-04-21 08:59:36.000000000 -0600 @@ -0,0 +1,13 @@ +#ifndef _LINUX_SWAPFILE_H +#define _LINUX_SWAPFILE_H + +/* + * these were static in swapfile.c but frontswap.c needs them and we don't + * want to expose them to the dozens of source files that include swap.h + */ +extern spinlock_t swap_lock; +extern struct swap_list_t swap_list; +extern struct swap_info_struct *swap_info[]; +extern int try_to_unuse(unsigned int, bool, unsigned long); + +#endif /* _LINUX_SWAPFILE_H */ --- linux-2.6.34-rc5/include/linux/swap.h 2010-04-19 17:29:56.000000000 -0600 +++ linux-2.6.34-rc5-frontswap/include/linux/swap.h 2010-04-21 08:59:36.000000000 -0600 @@ -182,6 +182,8 @@ struct swap_info_struct { struct block_device *bdev; /* swap device or bdev of swap file */ struct file *swap_file; /* seldom referenced */ unsigned int old_block_size; /* seldom referenced */ + unsigned long *frontswap_map; /* frontswap in-use, one bit per page */ + unsigned int frontswap_pages; /* frontswap pages in-use counter */ }; struct swap_list_t { -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org