From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f49.google.com (mail-pa0-f49.google.com [209.85.220.49]) by kanga.kvack.org (Postfix) with ESMTP id 8A08C6B0036 for ; Wed, 23 Jul 2014 09:55:21 -0400 (EDT) Received: by mail-pa0-f49.google.com with SMTP id hz1so1760560pad.22 for ; Wed, 23 Jul 2014 06:55:21 -0700 (PDT) Received: from mga01.intel.com (mga01.intel.com. [192.55.52.88]) by mx.google.com with ESMTP id q9si1320123pdj.265.2014.07.23.06.55.20 for ; Wed, 23 Jul 2014 06:55:20 -0700 (PDT) Date: Wed, 23 Jul 2014 09:55:14 -0400 From: Matthew Wilcox Subject: Re: [PATCH v8 10/22] Replace the XIP page fault handler with the DAX page fault handler Message-ID: <20140723135514.GB6754@linux.intel.com> References: <00ad731b459e32ce965af8530bcd611a141e41b6.1406058387.git.matthew.r.wilcox@intel.com> <20140723121025.GE10317@node.dhcp.inet.fi> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140723121025.GE10317@node.dhcp.inet.fi> Sender: owner-linux-mm@kvack.org List-ID: To: "Kirill A. Shutemov" Cc: Matthew Wilcox , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org On Wed, Jul 23, 2014 at 03:10:25PM +0300, Kirill A. Shutemov wrote: > > +int dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf, > > + get_block_t get_block) > > +{ > > + int result; > > + struct super_block *sb = file_inode(vma->vm_file)->i_sb; > > + > > + if (vmf->flags & FAULT_FLAG_WRITE) { > > Nobody seems calls sb_start_pagefault() in fault handler. > Do you mean FAULT_FLAG_MKWRITE? We need to call sb_start_pagefault() if we're going to make a modification to the filesystem. Admittedly, we don't know if we're going to make a modification at this point, but if we're taking a write fault on a hole, we will be. We can skip the call to sb_start_pagefault() if we're taking a read fault. > > +int dax_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf, > > + get_block_t get_block) > > +{ > > + return dax_fault(vma, vmf, get_block); > > +} > > +EXPORT_SYMBOL_GPL(dax_mkwrite); > > I don't think we want to introduce new exported symbol just for dummy > wrapper. Just use ".page_mkwrite = foo_fault,". perf and selinux do > this. > Or add #define into header file if you want better readability. They were different at one time ... agreed, I can just make them an alias for now. -- 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