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>
diff --git a/fs/ufs/util.c b/fs/ufs/util.c
index 85a7fc9..d2c36d5 100644
--- a/fs/ufs/util.c
+++ b/fs/ufs/util.c
@@ -113,21 +113,17 @@
 	}
 }
 
-void ubh_ll_rw_block(int rw, struct ufs_buffer_head *ubh)
+void ubh_sync_block(struct ufs_buffer_head *ubh)
 {
-	if (!ubh)
-		return;
+	if (ubh) {
+		unsigned i;
 
-	ll_rw_block(rw, ubh->count, ubh->bh);
-}
+		for (i = 0; i < ubh->count; i++)
+			write_dirty_buffer(ubh->bh[i], WRITE);
 
-void ubh_wait_on_buffer (struct ufs_buffer_head * ubh)
-{
-	unsigned i;
-	if (!ubh)
-		return;
-	for ( i = 0; i < ubh->count; i++ )
-		wait_on_buffer (ubh->bh[i]);
+		for (i = 0; i < ubh->count; i++)
+			wait_on_buffer(ubh->bh[i]);
+	}
 }
 
 void ubh_bforget (struct ufs_buffer_head * ubh)