From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754903AbXLEH5f (ORCPT ); Wed, 5 Dec 2007 02:57:35 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754130AbXLEHz1 (ORCPT ); Wed, 5 Dec 2007 02:55:27 -0500 Received: from cantor.suse.de ([195.135.220.2]:38637 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752047AbXLEHzK (ORCPT ); Wed, 5 Dec 2007 02:55:10 -0500 Message-Id: <20071205071627.577776000@nick.local0.net> References: <20071205071547.701344000@nick.local0.net> User-Agent: quilt/0.46-14 Date: Wed, 05 Dec 2007 18:15:55 +1100 From: npiggin@suse.de To: akpm@linux-foundation.org Cc: linux-fbdev-devel@lists.sourceforge.net, jayakumar.lkml@gmail.com, lethal@linux-sh.org, linux-kernel@vger.kernel.org Subject: [patch 08/18] fb: defio nopage Content-Disposition: inline; filename=fb-defio-nopage.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Convert fb defio from nopage to fault. Switch from OOM to SIGBUS if the resource is not available. Signed-off-by: Nick Piggin Cc: linux-fbdev-devel@lists.sourceforge.net Cc: jayakumar.lkml@gmail.com Cc: lethal@linux-sh.org Cc: linux-kernel@vger.kernel.org --- Documentation/fb/deferred_io.txt | 6 +++--- drivers/video/fb_defio.c | 17 ++++++++--------- 2 files changed, 11 insertions(+), 12 deletions(-) Index: linux-2.6/drivers/video/fb_defio.c =================================================================== --- linux-2.6.orig/drivers/video/fb_defio.c +++ linux-2.6/drivers/video/fb_defio.c @@ -25,8 +25,8 @@ #include /* this is to find and return the vmalloc-ed fb pages */ -static struct page* fb_deferred_io_nopage(struct vm_area_struct *vma, - unsigned long vaddr, int *type) +static int fb_deferred_io_fault(struct vm_area_struct *vma, + struct vm_fault *vmf) { unsigned long offset; struct page *page; @@ -34,18 +34,17 @@ static struct page* fb_deferred_io_nopag /* info->screen_base is in System RAM */ void *screen_base = (void __force *) info->screen_base; - offset = (vaddr - vma->vm_start) + (vma->vm_pgoff << PAGE_SHIFT); + offset = vmf->pgoff << PAGE_SHIFT; if (offset >= info->fix.smem_len) - return NOPAGE_SIGBUS; + return VM_FAULT_SIGBUS; page = vmalloc_to_page(screen_base + offset); if (!page) - return NOPAGE_OOM; + return VM_FAULT_SIGBUS; get_page(page); - if (type) - *type = VM_FAULT_MINOR; - return page; + vmf->page = page; + return 0; } int fb_deferred_io_fsync(struct file *file, struct dentry *dentry, int datasync) @@ -84,7 +83,7 @@ static int fb_deferred_io_mkwrite(struct } static struct vm_operations_struct fb_deferred_io_vm_ops = { - .nopage = fb_deferred_io_nopage, + .fault = fb_deferred_io_fault, .page_mkwrite = fb_deferred_io_mkwrite, }; Index: linux-2.6/Documentation/fb/deferred_io.txt =================================================================== --- linux-2.6.orig/Documentation/fb/deferred_io.txt +++ linux-2.6/Documentation/fb/deferred_io.txt @@ -7,10 +7,10 @@ IO. The following example may be a usefu works: - userspace app like Xfbdev mmaps framebuffer -- deferred IO and driver sets up nopage and page_mkwrite handlers +- deferred IO and driver sets up fault and page_mkwrite handlers - userspace app tries to write to mmaped vaddress -- we get pagefault and reach nopage handler -- nopage handler finds and returns physical page +- we get pagefault and reach fault handler +- fault handler finds and returns physical page - we get page_mkwrite where we add this page to a list - schedule a workqueue task to be run after a delay - app continues writing to that page with no additional cost. this is --