Remove B_READ, B_WRITE and B_FREEBUF and replace them with a new

field in struct buf: b_iocmd.  The b_iocmd is enforced to have
exactly one bit set.

B_WRITE was bogusly defined as zero giving rise to obvious coding
mistakes.

Also eliminate the redundant struct buf flag B_CALL, it can just
as efficiently be done by comparing b_iodone to NULL.

Should you get a panic or drop into the debugger, complaining about
"b_iocmd", don't continue.  It is likely to write on your disk
where it should have been reading.

This change is a step in the direction towards a stackable BIO capability.

A lot of this patch were machine generated (Thanks to style(9) compliance!)

Vinum users:  Greg has not had time to test this yet, be careful.

1 files changed, 1 insertions, 1 deletions

diff --git a/sys/dev/mcd/mcd.c b/sys/dev/mcd/mcd.c
index 923ec0f..8b41449 100644
--- a/sys/dev/mcd/mcd.c
+++ b/sys/dev/mcd/mcd.c
@@ -414,7 +414,7 @@ MCD_TRACE("strategy: drive not valid\n");
 	}
 
 	/* read only */
-	if (!(bp->b_flags & B_READ)) {
+	if (!(bp->b_iocmd == BIO_READ)) {
 		bp->b_error = EROFS;
 		goto bad;
 	}