block: get rid of the WRITE_ODIRECT flag

Hi,

The WRITE_ODIRECT flag is only used in one place, and that code path
happens to also call blk_run_address_space.  The introduction of this
flag, then, could result in the device being unplugged twice for every
I/O.

Further, with the batching changes in the next patch, we don't want an
O_DIRECT write to imply a queue unplug.

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2 files changed, 1 insertions, 3 deletions

diff --git a/fs/direct-io.c b/fs/direct-io.c
index 8b10b87dc01a..c86d35f142de 100644
--- a/fs/direct-io.c
+++ b/fs/direct-io.c
@@ -1124,7 +1124,7 @@ __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
         int acquire_i_mutex = 0;
 
         if (rw & WRITE)
-                rw = WRITE_ODIRECT;
+                rw = WRITE_SYNC_PLUG;
 
         if (bdev)
                 bdev_blkbits = blksize_bits(bdev_logical_block_size(bdev));
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 2620a8c63571..2f5fca4147c2 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -129,7 +129,6 @@ struct inodes_stat_t {
  * WRITE_SYNC           Like WRITE_SYNC_PLUG, but also unplugs the device
  *                      immediately after submission. The write equivalent
  *                      of READ_SYNC.
- * WRITE_ODIRECT        Special case write for O_DIRECT only.
  * SWRITE_SYNC
  * SWRITE_SYNC_PLUG     Like WRITE_SYNC/WRITE_SYNC_PLUG, but locks the buffer.
  *                      See SWRITE.
@@ -151,7 +150,6 @@ struct inodes_stat_t {
 #define READ_META       (READ | (1 << BIO_RW_META))
 #define WRITE_SYNC_PLUG (WRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_NOIDLE))
 #define WRITE_SYNC      (WRITE_SYNC_PLUG | (1 << BIO_RW_UNPLUG))
-#define WRITE_ODIRECT   (WRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG))
 #define SWRITE_SYNC_PLUG        \
                         (SWRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_NOIDLE))
 #define SWRITE_SYNC     (SWRITE_SYNC_PLUG | (1 << BIO_RW_UNPLUG))