From 647d1e4c5235763b83fbfe74a09d148edc6ca152 Mon Sep 17 00:00:00 2001
From: Fengguang Wu <fengguang.wu@intel.com>
Date: Thu, 9 Aug 2012 15:23:09 +0200
Subject: [PATCH] block: move down direct IO plugging
Move unplugging for direct I/O from around ->direct_IO() down to
do_blockdev_direct_IO(). This implicitly adds plugging for direct
writes.
CC: Li Shaohua <shli@fusionio.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
fs/direct-io.c | 5 +++++
mm/filemap.c | 4 ----
2 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/fs/direct-io.c b/fs/direct-io.c
index 1faf4cb56f39..f86c720dba0e 100644
--- a/fs/direct-io.c
+++ b/fs/direct-io.c
@@ -1062,6 +1062,7 @@ do_blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
unsigned long user_addr;
size_t bytes;
struct buffer_head map_bh = { 0, };
+ struct blk_plug plug;
if (rw & WRITE)
rw = WRITE_ODIRECT;
@@ -1177,6 +1178,8 @@ do_blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
PAGE_SIZE - user_addr / PAGE_SIZE);
}
+ blk_start_plug(&plug);
+
for (seg = 0; seg < nr_segs; seg++) {
user_addr = (unsigned long)iov[seg].iov_base;
sdio.size += bytes = iov[seg].iov_len;
@@ -1235,6 +1238,8 @@ do_blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
if (sdio.bio)
dio_bio_submit(dio, &sdio);
+ blk_finish_plug(&plug);
+
/*
* It is possible that, we return short IO due to end of file.
* In that case, we need to release all the pages we got hold on.
diff --git a/mm/filemap.c b/mm/filemap.c
index 2b0952974cb9..384344575c37 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1412,12 +1412,8 @@ generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
retval = filemap_write_and_wait_range(mapping, pos,
pos + iov_length(iov, nr_segs) - 1);
if (!retval) {
- struct blk_plug plug;
-
- blk_start_plug(&plug);
retval = mapping->a_ops->direct_IO(READ, iocb,
iov, pos, nr_segs);
- blk_finish_plug(&plug);
}
if (retval > 0) {
*ppos = pos + retval;