From: Zheng Liu Subject: [RFC][PATCH v2 1/3] ext4: split ext4_file_write into buffered IO and direct IO Date: Thu, 14 Jun 2012 11:32:08 +0800 Message-ID: <1339644730-6204-2-git-send-email-wenqing.lz@taobao.com> References: <1339644730-6204-1-git-send-email-wenqing.lz@taobao.com> Cc: Tao Ma , Eric Sandeen , Zheng Liu To: linux-ext4@vger.kernel.org Return-path: Received: from mail-pz0-f46.google.com ([209.85.210.46]:64546 "EHLO mail-pz0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755096Ab2FNDYa (ORCPT ); Wed, 13 Jun 2012 23:24:30 -0400 Received: by dady13 with SMTP id y13so1935499dad.19 for ; Wed, 13 Jun 2012 20:24:30 -0700 (PDT) In-Reply-To: <1339644730-6204-1-git-send-email-wenqing.lz@taobao.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: From: Zheng Liu ext4_file_dio_write is defined in order to split buffered IO and direct IO in ext4. This patch just refactor some stuff in write path. CC: Tao Ma CC: Eric Sandeen Signed-off-by: Zheng Liu --- fs/ext4/file.c | 60 +++++++++++++++++++++++++++++++++++-------------------- 1 files changed, 38 insertions(+), 22 deletions(-) diff --git a/fs/ext4/file.c b/fs/ext4/file.c index 8c7642a..a10dc77 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -90,34 +90,16 @@ ext4_unaligned_aio(struct inode *inode, const struct iovec *iov, } static ssize_t -ext4_file_write(struct kiocb *iocb, const struct iovec *iov, - unsigned long nr_segs, loff_t pos) +ext4_file_dio_write(struct kiocb *iocb, const struct iovec *iov, + unsigned long nr_segs, loff_t pos) { struct inode *inode = iocb->ki_filp->f_path.dentry->d_inode; int unaligned_aio = 0; ssize_t ret; - /* - * If we have encountered a bitmap-format file, the size limit - * is smaller than s_maxbytes, which is for extent-mapped files. - */ - - if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) { - struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); - size_t length = iov_length(iov, nr_segs); - - if ((pos > sbi->s_bitmap_maxbytes || - (pos == sbi->s_bitmap_maxbytes && length > 0))) - return -EFBIG; - - if (pos + length > sbi->s_bitmap_maxbytes) { - nr_segs = iov_shorten((struct iovec *)iov, nr_segs, - sbi->s_bitmap_maxbytes - pos); - } - } else if (unlikely((iocb->ki_filp->f_flags & O_DIRECT) && - !is_sync_kiocb(iocb))) { + if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) && + !is_sync_kiocb(iocb)) unaligned_aio = ext4_unaligned_aio(inode, iov, nr_segs, pos); - } /* Unaligned direct AIO must be serialized; see comment above */ if (unaligned_aio) { @@ -141,6 +123,40 @@ ext4_file_write(struct kiocb *iocb, const struct iovec *iov, return ret; } +static ssize_t +ext4_file_write(struct kiocb *iocb, const struct iovec *iov, + unsigned long nr_segs, loff_t pos) +{ + struct inode *inode = iocb->ki_filp->f_path.dentry->d_inode; + ssize_t ret; + + /* + * If we have encountered a bitmap-format file, the size limit + * is smaller than s_maxbytes, which is for extent-mapped files. + */ + + if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) { + struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); + size_t length = iov_length(iov, nr_segs); + + if ((pos > sbi->s_bitmap_maxbytes || + (pos == sbi->s_bitmap_maxbytes && length > 0))) + return -EFBIG; + + if (pos + length > sbi->s_bitmap_maxbytes) { + nr_segs = iov_shorten((struct iovec *)iov, nr_segs, + sbi->s_bitmap_maxbytes - pos); + } + } + + if (unlikely(iocb->ki_filp->f_flags & O_DIRECT)) + ret = ext4_file_dio_write(iocb, iov, nr_segs, pos); + else + ret = generic_file_aio_write(iocb, iov, nr_segs, pos); + + return ret; +} + static const struct vm_operations_struct ext4_file_vm_ops = { .fault = filemap_fault, .page_mkwrite = ext4_page_mkwrite, -- 1.7.4.1