remove SWRITE* I/O types

These flags aren't real I/O types, but tell ll_rw_block to always
lock the buffer instead of giving up on a failed trylock.

Instead add a new write_dirty_buffer helper that implements this semantic
and use it from the existing SWRITE* callers.  Note that the ll_rw_block
code had a bug where it didn't promote WRITE_SYNC_PLUG properly, which
this patch fixes.

In the ufs code clean up the helper that used to call ll_rw_block
to mirror sync_dirty_buffer, which is the function it implements for
compound buffers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2 files changed, 1 insertions, 9 deletions

diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h
index 72c1cf83eb85..ec94c12f21da 100644
--- a/include/linux/buffer_head.h
+++ b/include/linux/buffer_head.h
@@ -182,6 +182,7 @@ void __lock_buffer(struct buffer_head *bh);
 void ll_rw_block(int, int, struct buffer_head * bh[]);
 int sync_dirty_buffer(struct buffer_head *bh);
 int __sync_dirty_buffer(struct buffer_head *bh, int rw);
+void write_dirty_buffer(struct buffer_head *bh, int rw);
 int submit_bh(int, struct buffer_head *);
 void write_boundary_block(struct block_device *bdev,
                         sector_t bblock, unsigned blocksize);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 9a96b4d83fc1..29f7c975304c 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -125,9 +125,6 @@ struct inodes_stat_t {
  *                      block layer could (in theory) choose to ignore this
  *                      request if it runs into resource problems.
  * WRITE                A normal async write. Device will be plugged.
- * SWRITE               Like WRITE, but a special case for ll_rw_block() that
- *                      tells it to lock the buffer first. Normally a buffer
- *                      must be locked before doing IO.
  * WRITE_SYNC_PLUG      Synchronous write. Identical to WRITE, but passes down
  *                      the hint that someone will be waiting on this IO
  *                      shortly. The device must still be unplugged explicitly,
@@ -138,9 +135,6 @@ struct inodes_stat_t {
  *                      immediately after submission. The write equivalent
  *                      of READ_SYNC.
  * WRITE_ODIRECT_PLUG   Special case write for O_DIRECT only.
- * SWRITE_SYNC
- * SWRITE_SYNC_PLUG     Like WRITE_SYNC/WRITE_SYNC_PLUG, but locks the buffer.
- *                      See SWRITE.
  * WRITE_BARRIER        Like WRITE_SYNC, but tells the block layer that all
  *                      previously submitted writes must be safely on storage
  *                      before this one is started. Also guarantees that when
@@ -155,7 +149,6 @@ struct inodes_stat_t {
 #define READ                    0
 #define WRITE                   RW_MASK
 #define READA                   RWA_MASK
-#define SWRITE                  (WRITE | READA)
 
 #define READ_SYNC               (READ | REQ_SYNC | REQ_UNPLUG)
 #define READ_META               (READ | REQ_META)
@@ -165,8 +158,6 @@ struct inodes_stat_t {
 #define WRITE_META              (WRITE | REQ_META)
 #define WRITE_BARRIER           (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG | \
                                  REQ_HARDBARRIER)
-#define SWRITE_SYNC_PLUG        (SWRITE | REQ_SYNC | REQ_NOIDLE)
-#define SWRITE_SYNC             (SWRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG)
 
 /*
  * These aren't really reads or writes, they pass down information about