Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966329AbWKNUMZ (ORCPT ); Tue, 14 Nov 2006 15:12:25 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S966323AbWKNUJk (ORCPT ); Tue, 14 Nov 2006 15:09:40 -0500 Received: from mx1.redhat.com ([66.187.233.31]:53929 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S966310AbWKNUJP (ORCPT ); Tue, 14 Nov 2006 15:09:15 -0500 From: David Howells Subject: [PATCH 09/19] CacheFiles: Permit the page lock state to be monitored Date: Tue, 14 Nov 2006 20:06:41 +0000 To: torvalds@osdl.org, akpm@osdl.org, sds@tycho.nsa.gov, trond.myklebust@fys.uio.no Cc: dhowells@redhat.com, selinux@tycho.nsa.gov, linux-kernel@vger.kernel.org, aviro@redhat.com, steved@redhat.com Message-Id: <20061114200641.12943.98546.stgit@warthog.cambridge.redhat.com> In-Reply-To: <20061114200621.12943.18023.stgit@warthog.cambridge.redhat.com> References: <20061114200621.12943.18023.stgit@warthog.cambridge.redhat.com> Content-Type: text/plain; charset=utf-8; format=fixed Content-Transfer-Encoding: 8bit User-Agent: StGIT/0.10 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2131 Lines: 64 Add a function to install a monitor on the page lock waitqueue for a particular page, thus allowing the page being unlocked to be detected. This is used by CacheFiles to detect read completion on a page in the backing filesystem so that it can then copy the data to the waiting netfs page. Signed-Off-By: David Howells --- include/linux/pagemap.h | 5 +++++ mm/filemap.c | 19 +++++++++++++++++++ 2 files changed, 24 insertions(+), 0 deletions(-) diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 24fdc48..a86693c 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -200,6 +200,11 @@ static inline void wait_on_page_fs_misc( extern void fastcall end_page_fs_misc(struct page *page); /* + * Add an arbitrary waiter to a page's wait queue + */ +extern void add_page_wait_queue(struct page *page, wait_queue_t *waiter); + +/* * Fault a userspace page into pagetables. Return non-zero on a fault. * * This assumes that two userspace pages are always sufficient. That's diff --git a/mm/filemap.c b/mm/filemap.c index b9eb8b2..4c9c1ac 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -517,6 +517,25 @@ void fastcall wait_on_page_bit(struct pa EXPORT_SYMBOL(wait_on_page_bit); /** + * add_page_wait_queue - Add an arbitrary waiter to a page's wait queue + * @page - Page defining the wait queue of interest + * @waiter - Waiter to add to the queue + * + * Add an arbitrary @waiter to the wait queue for the nominated @page. + */ +void add_page_wait_queue(struct page *page, wait_queue_t *waiter) +{ + wait_queue_head_t *q = page_waitqueue(page); + unsigned long flags; + + spin_lock_irqsave(&q->lock, flags); + __add_wait_queue(q, waiter); + spin_unlock_irqrestore(&q->lock, flags); +} + +EXPORT_SYMBOL_GPL(add_page_wait_queue); + +/** * unlock_page - unlock a locked page * @page: the page * - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/