From: Saugata Das Subject: [PATCH 1/2] block: add BH_Meta flag Date: Fri, 11 May 2012 20:32:56 +0530 Message-ID: <1336748577-9258-1-git-send-email-saugata.das@stericsson.com> Mime-Version: 1.0 Content-Type: text/plain Cc: , , , , , Saugata Das To: , Return-path: Received: from eu1sys200aog104.obsmtp.com ([207.126.144.117]:47104 "EHLO eu1sys200aog104.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752082Ab2EKPHP (ORCPT ); Fri, 11 May 2012 11:07:15 -0400 Sender: linux-ext4-owner@vger.kernel.org List-ID: From: Saugata Das Today, storage devices like eMMC has special features like data tagging (introduced in MMC-4.5 version) in order to improve performance of some specific writes. On MMC stack, data tagging is used for all writes which has REQ_META flag set. This patch adds the capability to add REQ_META flag during meta data write. Signed-off-by: Saugata Das --- fs/buffer.c | 10 ++++++++-- include/linux/buffer_head.h | 2 ++ 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/fs/buffer.c b/fs/buffer.c index 36d6665..688b38b 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -1685,7 +1685,10 @@ static int __block_write_full_page(struct inode *inode, struct page *page, do { struct buffer_head *next = bh->b_this_page; if (buffer_async_write(bh)) { - submit_bh(write_op, bh); + if (buffer_meta(bh)) + submit_bh(write_op | REQ_META, bh); + else + submit_bh(write_op, bh); nr_underway++; } bh = next; @@ -1739,7 +1742,10 @@ recover: struct buffer_head *next = bh->b_this_page; if (buffer_async_write(bh)) { clear_buffer_dirty(bh); - submit_bh(write_op, bh); + if (buffer_meta(bh)) + submit_bh(write_op | REQ_META, bh); + else + submit_bh(write_op, bh); nr_underway++; } bh = next; diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h index ef26043..0776564 100644 --- a/include/linux/buffer_head.h +++ b/include/linux/buffer_head.h @@ -34,6 +34,7 @@ enum bh_state_bits { BH_Write_EIO, /* I/O error on write */ BH_Unwritten, /* Buffer is allocated on disk but not written */ BH_Quiet, /* Buffer Error Prinks to be quiet */ + BH_Meta, /* Is meta */ BH_PrivateStart,/* not a state bit, but the first bit available * for private allocation by other entities @@ -126,6 +127,7 @@ BUFFER_FNS(Delay, delay) BUFFER_FNS(Boundary, boundary) BUFFER_FNS(Write_EIO, write_io_error) BUFFER_FNS(Unwritten, unwritten) +BUFFER_FNS(Meta, meta) #define bh_offset(bh) ((unsigned long)(bh)->b_data & ~PAGE_MASK) #define touch_buffer(bh) mark_page_accessed(bh->b_page) -- 1.7.4.3