From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta12.messagelabs.com (mail6.bemta12.messagelabs.com [216.82.250.247]) by kanga.kvack.org (Postfix) with ESMTP id C81E86B0023 for ; Thu, 19 May 2011 18:49:13 -0400 (EDT) Received: from d03relay03.boulder.ibm.com (d03relay03.boulder.ibm.com [9.17.195.228]) by e38.co.us.ibm.com (8.14.4/8.13.1) with ESMTP id p4JMf4bw031135 for ; Thu, 19 May 2011 16:41:04 -0600 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d03relay03.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p4JMn7A7161504 for ; Thu, 19 May 2011 16:49:07 -0600 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p4JGmcMj026879 for ; Thu, 19 May 2011 10:48:40 -0600 Subject: [PATCH 3/3] mm: Provide stub page_mkwrite functionality to stabilize pages during writes From: "Darrick J. Wong" Date: Thu, 19 May 2011 15:49:03 -0700 Message-ID: <20110519224903.28755.2703.stgit@elm3c44.beaverton.ibm.com> In-Reply-To: <20110519224841.28755.80650.stgit@elm3c44.beaverton.ibm.com> References: <20110519224841.28755.80650.stgit@elm3c44.beaverton.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Alexander Viro , "Darrick J. Wong" Cc: Jens Axboe , Theodore Tso , "Martin K. Petersen" , Jeff Layton , Dave Chinner , linux-kernel , Dave Hansen , Christoph Hellwig , linux-mm@kvack.org, Chris Mason , Joel Becker , linux-scsi , linux-fsdevel , Jan Kara , linux-ext4@vger.kernel.org, Mingming Cao For filesystems that do not provide any page_mkwrite handler, provide a stub page_mkwrite function that locks the page and waits for pending writeback to complete. This is needed to stabilize pages during writes for a large variety of filesystem drivers (ext2, ext3, vfat, hfs...). Signed-off-by: Darrick J. Wong --- mm/filemap.c | 19 +++++++++++++++++++ 1 files changed, 19 insertions(+), 0 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index fd0e7f2..2a922b4 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1713,8 +1713,27 @@ page_not_uptodate: } EXPORT_SYMBOL(filemap_fault); +static int stub_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) +{ + struct page *page = vmf->page; + struct inode *inode = vma->vm_file->f_path.dentry->d_inode; + loff_t size; + + lock_page(page); + size = i_size_read(inode); + if ((page->mapping != inode->i_mapping) || + (page_offset(page) > size)) { + /* page got truncated out from underneath us */ + unlock_page(page); + return VM_FAULT_NOPAGE; + } + wait_on_page_writeback(page); + return VM_FAULT_LOCKED; +} + const struct vm_operations_struct generic_file_vm_ops = { .fault = filemap_fault, + .page_mkwrite = stub_page_mkwrite, }; /* This is used for a general mmap of a disk file */ -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org