From mboxrd@z Thu Jan 1 00:00:00 1970 From: Theodore Ts'o Subject: [PATCH 3/5] libext2fs: make read_bitmaps() more efficient when using direct I/O Date: Mon, 7 May 2012 14:56:23 -0400 Message-ID: <1336416985-24605-4-git-send-email-tytso@mit.edu> References: <1336416985-24605-1-git-send-email-tytso@mit.edu> Cc: ksumrall@google.com, Theodore Ts'o To: Ext4 Developers List Return-path: Received: from li9-11.members.linode.com ([67.18.176.11]:38761 "EHLO test.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751058Ab2EGS42 (ORCPT ); Mon, 7 May 2012 14:56:28 -0400 In-Reply-To: <1336416985-24605-1-git-send-email-tytso@mit.edu> Sender: linux-ext4-owner@vger.kernel.org List-ID: Read in a full block for each allocation bitmap, to avoid using a kernel bounce buffer when using direct I/O. Signed-off-by: "Theodore Ts'o" --- lib/ext2fs/rw_bitmaps.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/lib/ext2fs/rw_bitmaps.c b/lib/ext2fs/rw_bitmaps.c index 1d5f7b2..81e09c0 100644 --- a/lib/ext2fs/rw_bitmaps.c +++ b/lib/ext2fs/rw_bitmaps.c @@ -166,6 +166,9 @@ static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block) EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); + if ((block_nbytes > fs->blocksize) || (inode_nbytes > fs->blocksize)) + return EXT2_ET_CORRUPT_SUPERBLOCK; + fs->write_bitmaps = ext2fs_write_bitmaps; if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super, @@ -186,7 +189,7 @@ static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block) if (do_image) retval = ext2fs_get_mem(fs->blocksize, &block_bitmap); else - retval = ext2fs_get_memalign((unsigned) block_nbytes, + retval = ext2fs_get_memalign(fs->blocksize, fs->blocksize, &block_bitmap); @@ -202,8 +205,7 @@ 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(do_image ? fs->blocksize : - (unsigned) inode_nbytes, &inode_bitmap); + retval = ext2fs_get_mem(fs->blocksize, &inode_bitmap); if (retval) goto cleanup; } else @@ -261,7 +263,7 @@ static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block) blk = 0; if (blk) { retval = io_channel_read_blk64(fs->io, blk, - -block_nbytes, block_bitmap); + 1, block_bitmap); if (retval) { retval = EXT2_ET_BLOCK_BITMAP_READ; goto cleanup; @@ -283,7 +285,7 @@ static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block) blk = 0; if (blk) { retval = io_channel_read_blk64(fs->io, blk, - -inode_nbytes, inode_bitmap); + 1, inode_bitmap); if (retval) { retval = EXT2_ET_INODE_BITMAP_READ; goto cleanup; -- 1.7.10.rc3