From: Saugata Das Subject: [PATCH v2 1/2] block: add BH_Meta flag Date: Thu, 17 May 2012 17:51:29 +0530 Message-ID: <1337257290-28547-1-git-send-email-saugata.das@stericsson.com> Mime-Version: 1.0 Content-Type: text/plain Cc: , , , , , , , , Saugata Das To: , , Return-path: Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org 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 changes in v2: Replaced the conditionals around submit_bh as suggested in the review comments from Boaz --- fs/buffer.c | 6 ++++-- include/linux/buffer_head.h | 2 ++ 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/buffer.c b/fs/buffer.c index 36d6665..942c75b 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -1685,7 +1685,8 @@ 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); + submit_bh(write_op | + (buffer_meta(bh) << __REQ_META), bh); nr_underway++; } bh = next; @@ -1739,7 +1740,8 @@ recover: struct buffer_head *next = bh->b_this_page; if (buffer_async_write(bh)) { clear_buffer_dirty(bh); - submit_bh(write_op, bh); + submit_bh(write_op | + (buffer_meta(bh) << __REQ_META), bh); nr_underway++; } bh = next; diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h index 458f497..13bba17 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 @@ -124,6 +125,7 @@ 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