From patchwork Tue May 3 16:55:20 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Allison Henderson X-Patchwork-Id: 93854 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 43F24B6EF7 for ; Wed, 4 May 2011 02:55:35 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753556Ab1ECQza (ORCPT ); Tue, 3 May 2011 12:55:30 -0400 Received: from e37.co.us.ibm.com ([32.97.110.158]:37063 "EHLO e37.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753963Ab1ECQz1 (ORCPT ); Tue, 3 May 2011 12:55:27 -0400 Received: from d03relay03.boulder.ibm.com (d03relay03.boulder.ibm.com [9.17.195.228]) by e37.co.us.ibm.com (8.14.4/8.13.1) with ESMTP id p43GqXVR029652 for ; Tue, 3 May 2011 10:52:33 -0600 Received: from d03av01.boulder.ibm.com (d03av01.boulder.ibm.com [9.17.195.167]) by d03relay03.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p43GtKw3157798 for ; Tue, 3 May 2011 10:55:20 -0600 Received: from d03av01.boulder.ibm.com (loopback [127.0.0.1]) by d03av01.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p43GtKNW028862 for ; Tue, 3 May 2011 10:55:20 -0600 Received: from [9.65.15.245] (sig-9-65-15-245.mts.ibm.com [9.65.15.245]) by d03av01.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id p43GtKo6028798 for ; Tue, 3 May 2011 10:55:20 -0600 Message-ID: <4DC03378.1020102@linux.vnet.ibm.com> Date: Tue, 03 May 2011 09:55:20 -0700 From: Allison Henderson User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.15) Gecko/20110303 Thunderbird/3.1.9 MIME-Version: 1.0 To: Ext4 Developers List Subject: [Ext4 punch hole 2/5 v6] Ext4 Punch Hole Support: Clear Hole Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org Sorry, I lost the subject header on this one. It's the same patch, but I'll resend to avoid confusion This patch adds routines needed to zero out the unblock aligned data of the hole. The existing ext4_block_truncate_page routine that is used to zero out unblock aligned data from truncate has been modified to accept a length parameter, and renamed to ext4_block_zero_page_range. The function can now be used to zero out the head of a block, the tail of a block, or the middle of a block. The existing ext4_block_truncate_page has now become a wrapper to this function Signed-off-by: Allison Henderson --- :100644 100644 5639fdf... 45136d8... M fs/ext4/ext4.h :100644 100644 a04128f... dc45631... M fs/ext4/inode.c fs/ext4/ext4.h | 2 ++ fs/ext4/inode.c | 33 +++++++++++++++++++++++++++++++-- 2 files changed, 33 insertions(+), 2 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 5639fdf..45136d8 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1743,6 +1743,8 @@ extern int ext4_writepage_trans_blocks(struct inode *); extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks); extern int ext4_block_truncate_page(handle_t *handle, struct address_space *mapping, loff_t from); +extern int ext4_block_zero_page_range(handle_t *handle, + struct address_space *mapping, loff_t from, loff_t length); extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf); extern qsize_t *ext4_get_reserved_space(struct inode *inode); extern void ext4_da_update_reserve_space(struct inode *inode, diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index a04128f..dc45631 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3915,9 +3915,30 @@ void ext4_set_aops(struct inode *inode) int ext4_block_truncate_page(handle_t *handle, struct address_space *mapping, loff_t from) { + unsigned offset = from & (PAGE_CACHE_SIZE-1); + unsigned length; + unsigned blocksize; + struct inode *inode = mapping->host; + + blocksize = inode->i_sb->s_blocksize; + length = blocksize - (offset & (blocksize - 1)); + + return ext4_block_zero_page_range(handle, mapping, from, length); +} + +/* + * ext4_block_zero_page_range() zeros out a mapping of length 'length' + * starting from file offset 'from'. The range to be zero'd must + * be contained with in one block. If the specified range exceeds + * the end of the block it will be shortened to end of the block + * that cooresponds to 'from' + */ +int ext4_block_zero_page_range(handle_t *handle, + struct address_space *mapping, loff_t from, loff_t length) +{ ext4_fsblk_t index = from >> PAGE_CACHE_SHIFT; unsigned offset = from & (PAGE_CACHE_SIZE-1); - unsigned blocksize, length, pos; + unsigned blocksize, max, pos; ext4_lblk_t iblock; struct inode *inode = mapping->host; struct buffer_head *bh; @@ -3930,7 +3951,15 @@ int ext4_block_truncate_page(handle_t *handle, return -EINVAL; blocksize = inode->i_sb->s_blocksize; - length = blocksize - (offset & (blocksize - 1)); + max = blocksize - (offset & (blocksize - 1)); + + /* + * correct length if it does not fall between + * 'from' and the end of the block + */ + if (length > max || length < 0) + length = max; + iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); if (!page_has_buffers(page))