From patchwork Mon May 7 18:56:24 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Theodore Ts'o X-Patchwork-Id: 157384 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 BBDB6B6FAA for ; Tue, 8 May 2012 04:56:33 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757228Ab2EGS4b (ORCPT ); Mon, 7 May 2012 14:56:31 -0400 Received: from li9-11.members.linode.com ([67.18.176.11]:38764 "EHLO test.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752997Ab2EGS42 (ORCPT ); Mon, 7 May 2012 14:56:28 -0400 Received: from root (helo=tytso-glaptop.cam.corp.google.com) by test.thunk.org with local-esmtp (Exim 4.69) (envelope-from ) id 1SRT6h-0004OY-3v; Mon, 07 May 2012 18:56:27 +0000 Received: from tytso by tytso-glaptop.cam.corp.google.com with local (Exim 4.71) (envelope-from ) id 1SRT6f-0006Pg-Lb; Mon, 07 May 2012 14:56:25 -0400 From: Theodore Ts'o To: Ext4 Developers List Cc: ksumrall@google.com, Theodore Ts'o Subject: [PATCH 4/5] libext2fs: factor out I/O buffer allocation Date: Mon, 7 May 2012 14:56:24 -0400 Message-Id: <1336416985-24605-5-git-send-email-tytso@mit.edu> X-Mailer: git-send-email 1.7.10.rc3 In-Reply-To: <1336416985-24605-1-git-send-email-tytso@mit.edu> References: <1336416985-24605-1-git-send-email-tytso@mit.edu> X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: tytso@thunk.org X-SA-Exim-Scanned: No (on test.thunk.org); SAEximRunCond expanded to false Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org Create a new function, io_channel_alloc_buf() which allocates I/O buffers with appropriate alignment if we are using direct I/O. The original code was sometimes using a larger alignment factor than necessary, and would always request an aligned memory buffer even when it was not necessary since the block device was not opened with O_DIRECT. Signed-off-by: "Theodore Ts'o" --- lib/ext2fs/ext2_io.h | 2 ++ lib/ext2fs/inode.c | 4 ++-- lib/ext2fs/io_manager.c | 17 +++++++++++++++++ lib/ext2fs/openfs.c | 2 +- lib/ext2fs/rw_bitmaps.c | 16 ++++------------ lib/ext2fs/unix_io.c | 7 ++----- 6 files changed, 28 insertions(+), 20 deletions(-) diff --git a/lib/ext2fs/ext2_io.h b/lib/ext2fs/ext2_io.h index 95b8de3..1894fb8 100644 --- a/lib/ext2fs/ext2_io.h +++ b/lib/ext2fs/ext2_io.h @@ -122,6 +122,8 @@ extern errcode_t io_channel_write_blk64(io_channel channel, extern errcode_t io_channel_discard(io_channel channel, unsigned long long block, unsigned long long count); +extern errcode_t io_channel_alloc_buf(io_channel channel, + int count, void *ptr); /* unix_io.c */ extern io_manager unix_io_manager; diff --git a/lib/ext2fs/inode.c b/lib/ext2fs/inode.c index 6c524ff..77fc447 100644 --- a/lib/ext2fs/inode.c +++ b/lib/ext2fs/inode.c @@ -157,8 +157,8 @@ errcode_t ext2fs_open_inode_scan(ext2_filsys fs, int buffer_blocks, (fs->blocksize / scan->inode_size - 1)) * scan->inode_size / fs->blocksize; } - retval = ext2fs_get_memalign(scan->inode_buffer_blocks * fs->blocksize, - fs->blocksize, &scan->inode_buffer); + retval = io_channel_alloc_buf(fs->io, scan->inode_buffer_blocks, + &scan->inode_buffer); scan->done_group = 0; scan->done_group_data = 0; scan->bad_block_ptr = 0; diff --git a/lib/ext2fs/io_manager.c b/lib/ext2fs/io_manager.c index 25df59e..34e4859 100644 --- a/lib/ext2fs/io_manager.c +++ b/lib/ext2fs/io_manager.c @@ -111,3 +111,20 @@ errcode_t io_channel_discard(io_channel channel, unsigned long long block, return EXT2_ET_UNIMPLEMENTED; } + +errcode_t io_channel_alloc_buf(io_channel io, int count, void *ptr) +{ + size_t size; + + if (count == 0) + size = io->block_size; + else if (count > 0) + size = io->block_size * count; + else + size = -count; + + if (io->align) + return ext2fs_get_memalign(size, io->align, ptr); + else + return ext2fs_get_mem(size, ptr); +} diff --git a/lib/ext2fs/openfs.c b/lib/ext2fs/openfs.c index 220d954..482e4ab 100644 --- a/lib/ext2fs/openfs.c +++ b/lib/ext2fs/openfs.c @@ -144,7 +144,7 @@ errcode_t ext2fs_open2(const char *name, const char *io_options, goto cleanup; fs->image_io = fs->io; fs->io->app_data = fs; - retval = ext2fs_get_memalign(SUPERBLOCK_SIZE, 512, &fs->super); + retval = io_channel_alloc_buf(fs->io, -SUPERBLOCK_SIZE, &fs->super); if (retval) goto cleanup; if (flags & EXT2_FLAG_IMAGE_FILE) { diff --git a/lib/ext2fs/rw_bitmaps.c b/lib/ext2fs/rw_bitmaps.c index 81e09c0..53f6ec4 100644 --- a/lib/ext2fs/rw_bitmaps.c +++ b/lib/ext2fs/rw_bitmaps.c @@ -53,8 +53,7 @@ static errcode_t write_bitmaps(ext2_filsys fs, int do_inode, int do_block) inode_nbytes = block_nbytes = 0; if (do_block) { block_nbytes = EXT2_CLUSTERS_PER_GROUP(fs->super) / 8; - retval = ext2fs_get_memalign(fs->blocksize, fs->blocksize, - &block_buf); + retval = io_channel_alloc_buf(fs->io, 0, &block_buf); if (retval) goto errout; memset(block_buf, 0xff, fs->blocksize); @@ -62,8 +61,7 @@ static errcode_t write_bitmaps(ext2_filsys fs, int do_inode, int do_block) if (do_inode) { inode_nbytes = (size_t) ((EXT2_INODES_PER_GROUP(fs->super)+7) / 8); - retval = ext2fs_get_memalign(fs->blocksize, fs->blocksize, - &inode_buf); + retval = io_channel_alloc_buf(fs->io, 0, &inode_buf); if (retval) goto errout; memset(inode_buf, 0xff, fs->blocksize); @@ -186,13 +184,7 @@ static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block) retval = ext2fs_allocate_block_bitmap(fs, buf, &fs->block_map); if (retval) goto cleanup; - if (do_image) - retval = ext2fs_get_mem(fs->blocksize, &block_bitmap); - else - retval = ext2fs_get_memalign(fs->blocksize, - fs->blocksize, - &block_bitmap); - + retval = io_channel_alloc_buf(fs->io, 0, &block_bitmap); if (retval) goto cleanup; } else @@ -205,7 +197,7 @@ static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block) retval = ext2fs_allocate_inode_bitmap(fs, buf, &fs->inode_map); if (retval) goto cleanup; - retval = ext2fs_get_mem(fs->blocksize, &inode_bitmap); + retval = io_channel_alloc_buf(fs->io, 0, &inode_bitmap); if (retval) goto cleanup; } else diff --git a/lib/ext2fs/unix_io.c b/lib/ext2fs/unix_io.c index 8319eba..2ce0563 100644 --- a/lib/ext2fs/unix_io.c +++ b/lib/ext2fs/unix_io.c @@ -316,17 +316,14 @@ static errcode_t alloc_cache(io_channel channel, cache->in_use = 0; if (cache->buf) ext2fs_free_mem(&cache->buf); - retval = ext2fs_get_memalign(channel->block_size, - channel->align, &cache->buf); + retval = io_channel_alloc_buf(channel, 0, &cache->buf); if (retval) return retval; } if (channel->align) { if (data->bounce) ext2fs_free_mem(&data->bounce); - retval = ext2fs_get_memalign(channel->block_size, - channel->align, - &data->bounce); + retval = io_channel_alloc_buf(channel, 0, &data->bounce); } return retval; }