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.

4 files changed, 8 insertions, 4 deletions

diff --git a/sys/gnu/ext2fs/ext2_bmap.c b/sys/gnu/ext2fs/ext2_bmap.c
index 57cef46..ab5ebb5 100644
--- a/sys/gnu/ext2fs/ext2_bmap.c
+++ b/sys/gnu/ext2fs/ext2_bmap.c
@@ -192,7 +192,7 @@ ufs_bmaparray(vp, bn, bnp, ap, nump, runp, runb)
 				panic("ufs_bmaparray: indirect block not in cache");
 #endif
 			bp->b_blkno = blkptrtodb(ump, daddr);
-			bp->b_flags |= B_READ;
+			bp->b_iocmd = BIO_READ;
 			bp->b_flags &= ~(B_INVAL|B_ERROR);
 			vfs_busy_pages(bp, 0);
 			VOP_STRATEGY(bp->b_vp, bp);
diff --git a/sys/gnu/ext2fs/ext2_inode.c b/sys/gnu/ext2fs/ext2_inode.c
index 657f699..22847f5 100644
--- a/sys/gnu/ext2fs/ext2_inode.c
+++ b/sys/gnu/ext2fs/ext2_inode.c
@@ -37,6 +37,8 @@
  * SUCH DAMAGE.
  *
  *	@(#)ext2_inode.c	8.5 (Berkeley) 12/30/93
+ *
+ * $FreeBSD$
  */
 
 #include "opt_quota.h"
@@ -416,7 +418,7 @@ ext2_indirtrunc(ip, lbn, dbn, lastbn, level, countp)
 	bp = getblk(vp, lbn, (int)fs->s_blocksize, 0, 0);
 	if (bp->b_flags & (B_DONE | B_DELWRI)) {
 	} else {
-		bp->b_flags |= B_READ;
+		bp->b_iocmd = BIO_READ;
 		if (bp->b_bcount > bp->b_bufsize)
 			panic("ext2_indirtrunc: bad buffer size");
 		bp->b_blkno = dbn;
diff --git a/sys/gnu/fs/ext2fs/ext2_bmap.c b/sys/gnu/fs/ext2fs/ext2_bmap.c
index 57cef46..ab5ebb5 100644
--- a/sys/gnu/fs/ext2fs/ext2_bmap.c
+++ b/sys/gnu/fs/ext2fs/ext2_bmap.c
@@ -192,7 +192,7 @@ ufs_bmaparray(vp, bn, bnp, ap, nump, runp, runb)
 				panic("ufs_bmaparray: indirect block not in cache");
 #endif
 			bp->b_blkno = blkptrtodb(ump, daddr);
-			bp->b_flags |= B_READ;
+			bp->b_iocmd = BIO_READ;
 			bp->b_flags &= ~(B_INVAL|B_ERROR);
 			vfs_busy_pages(bp, 0);
 			VOP_STRATEGY(bp->b_vp, bp);
diff --git a/sys/gnu/fs/ext2fs/ext2_inode.c b/sys/gnu/fs/ext2fs/ext2_inode.c
index 657f699..22847f5 100644
--- a/sys/gnu/fs/ext2fs/ext2_inode.c
+++ b/sys/gnu/fs/ext2fs/ext2_inode.c
@@ -37,6 +37,8 @@
  * SUCH DAMAGE.
  *
  *	@(#)ext2_inode.c	8.5 (Berkeley) 12/30/93
+ *
+ * $FreeBSD$
  */
 
 #include "opt_quota.h"
@@ -416,7 +418,7 @@ ext2_indirtrunc(ip, lbn, dbn, lastbn, level, countp)
 	bp = getblk(vp, lbn, (int)fs->s_blocksize, 0, 0);
 	if (bp->b_flags & (B_DONE | B_DELWRI)) {
 	} else {
-		bp->b_flags |= B_READ;
+		bp->b_iocmd = BIO_READ;
 		if (bp->b_bcount > bp->b_bufsize)
 			panic("ext2_indirtrunc: bad buffer size");
 		bp->b_blkno = dbn;