Clustered read and write are switched at mount-option level.

1. Clustered I/O is switched by the MNT_NOCLUSTERR and MNT_NOCLUSTERW
   bits of the mnt_flag.  The sysctl variables, vfs.foo.doclusterread
   and vfs.foo.doclusterwrite are deleted.  Only mount option can
   control clustered I/O from userland.
2. When foofs_mount mounts block device, foofs_mount checks D_CLUSTERR
   and D_CLUSTERW bits of the d_flags member in the block device switch
   table.  If D_NOCLUSTERR / D_NOCLUSTERW are set, MNT_NOCLUSTERR /
   MNT_NOCLUSTERW bits will be set.  In this case, MNT_NOCLUSTERR and
   MNT_NOCLUSTERW cannot be cleared from userland.
3. Vnode driver disables both clustered read and write.
4. Union filesystem disables clutered write.

Reviewed by:	bde

4 files changed, 24 insertions, 23 deletions

diff --git a/sys/ufs/ffs/ffs_extern.h b/sys/ufs/ffs/ffs_extern.h
index 5c6a519..8fd7d70 100644
--- a/sys/ufs/ffs/ffs_extern.h
+++ b/sys/ufs/ffs/ffs_extern.h
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)ffs_extern.h	8.6 (Berkeley) 3/30/95
- * $Id: ffs_extern.h,v 1.15 1997/02/22 09:47:02 peter Exp $
+ * $Id: ffs_extern.h,v 1.16 1997/08/16 19:16:19 wollman Exp $
  */
 
 #ifndef _UFS_FFS_EXTERN_H
@@ -40,16 +40,14 @@
 /*
  * Sysctl values for the fast filesystem.
  */
-#define FFS_CLUSTERREAD		1	/* cluster reading enabled */
-#define FFS_CLUSTERWRITE	2	/* cluster writing enabled */
 #define FFS_REALLOCBLKS		3	/* block reallocation enabled */
 #define FFS_ASYNCFREE		4	/* asynchronous block freeing enabled */
 #define	FFS_MAXID		5	/* number of valid ffs ids */
 
 #define FFS_NAMES { \
 	{ 0, 0 }, \
-	{ "doclusterread", CTLTYPE_INT }, \
-	{ "doclusterwrite", CTLTYPE_INT }, \
+	{ 0, 0 }, \
+	{ 0, 0 }, \
 	{ "doreallocblks", CTLTYPE_INT }, \
 	{ "doasyncfree", CTLTYPE_INT }, \
 }
diff --git a/sys/ufs/ffs/ffs_vfsops.c b/sys/ufs/ffs/ffs_vfsops.c
index a835da5..c0dae9a 100644
--- a/sys/ufs/ffs/ffs_vfsops.c
+++ b/sys/ufs/ffs/ffs_vfsops.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)ffs_vfsops.c	8.31 (Berkeley) 5/20/95
- * $Id: ffs_vfsops.c,v 1.54 1997/09/02 20:06:46 bde Exp $
+ * $Id: ffs_vfsops.c,v 1.55 1997/09/07 16:20:59 bde Exp $
  */
 
 #include "opt_quota.h"
@@ -44,6 +44,7 @@
 #include <sys/vnode.h>
 #include <sys/mount.h>
 #include <sys/buf.h>
+#include <sys/conf.h>
 #include <sys/fcntl.h>
 #include <sys/disklabel.h>
 #include <sys/malloc.h>
@@ -155,9 +156,10 @@ ffs_mount( mp, path, data, ndp, p)
 			return (err);
 		}
 
-		/*
-		 * Attempt mount
-		 */
+		if (bdevsw[major(rootdev)]->d_flags & D_NOCLUSTERR)
+			mp->mnt_flag |= MNT_NOCLUSTERR;
+		if (bdevsw[major(rootdev)]->d_flags & D_NOCLUSTERW)
+			mp->mnt_flag |= MNT_NOCLUSTERW;
 		if( ( err = ffs_mountfs(rootvp, mp, p)) != 0) {
 			/* fs specific cleanup (if any)*/
 			goto error_1;
@@ -181,11 +183,17 @@ ffs_mount( mp, path, data, ndp, p)
 	/*
 	 * If updating, check whether changing from read-only to
 	 * read/write; if there is no device name, that's all we do.
+	 * Disallow clearing MNT_NOCLUSTERR and MNT_NOCLUSTERW flags,
+	 * if block device requests.
 	 */
 	if (mp->mnt_flag & MNT_UPDATE) {
 		ump = VFSTOUFS(mp);
 		fs = ump->um_fs;
 		err = 0;
+		if (bdevsw[major(ump->um_dev)]->d_flags & D_NOCLUSTERR)
+			mp->mnt_flag |= MNT_NOCLUSTERR;
+		if (bdevsw[major(ump->um_dev)]->d_flags & D_NOCLUSTERW)
+			mp->mnt_flag |= MNT_NOCLUSTERW;
 		if (fs->fs_ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) {
 			flags = WRITECLOSE;
 			if (mp->mnt_flag & MNT_FORCE)
@@ -275,6 +283,11 @@ ffs_mount( mp, path, data, ndp, p)
 		 ********************
 		 */
 
+		if (bdevsw[major(devvp->v_rdev)]->d_flags & D_NOCLUSTERR)
+			mp->mnt_flag |= MNT_NOCLUSTERR;
+		if (bdevsw[major(devvp->v_rdev)]->d_flags & D_NOCLUSTERW)
+			mp->mnt_flag |= MNT_NOCLUSTERW;
+
 		/*
 		 * Since this is a new mount, we want the names for
 		 * the device and the mount point copied in.  If an
diff --git a/sys/ufs/ffs/ffs_vnops.c b/sys/ufs/ffs/ffs_vnops.c
index a546fb8..084e3a9 100644
--- a/sys/ufs/ffs/ffs_vnops.c
+++ b/sys/ufs/ffs/ffs_vnops.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)ffs_vnops.c	8.15 (Berkeley) 5/14/95
- * $Id: ffs_vnops.c,v 1.28 1997/09/02 20:06:46 bde Exp $
+ * $Id: ffs_vnops.c,v 1.29 1997/09/14 02:58:05 peter Exp $
  */
 
 #include <sys/param.h>
@@ -239,17 +239,7 @@ VNODEOP_SET(ffs_vnodeop_opv_desc);
 VNODEOP_SET(ffs_specop_opv_desc);
 VNODEOP_SET(ffs_fifoop_opv_desc);
 
-/*
- * Enabling cluster read/write operations.
- */
-static int ffs_doclusterread = 1;
-static int ffs_doclusterwrite = 1;
-
 SYSCTL_NODE(_vfs, MOUNT_UFS, ffs, CTLFLAG_RW, 0, "FFS filesystem");
-SYSCTL_INT(_vfs_ffs, FFS_CLUSTERREAD, doclusterread,
-		   CTLFLAG_RW, &ffs_doclusterread, 0, "");
-SYSCTL_INT(_vfs_ffs, FFS_CLUSTERWRITE, doclusterwrite,
-		   CTLFLAG_RW, &ffs_doclusterwrite, 0, "");
 
 #include <ufs/ufs/ufs_readwrite.c>
 
diff --git a/sys/ufs/ufs/ufs_readwrite.c b/sys/ufs/ufs/ufs_readwrite.c
index c598833..929a289 100644
--- a/sys/ufs/ufs/ufs_readwrite.c
+++ b/sys/ufs/ufs/ufs_readwrite.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)ufs_readwrite.c	8.11 (Berkeley) 5/8/95
- * $Id: ufs_readwrite.c,v 1.29 1997/03/22 06:53:44 bde Exp $
+ * $Id: ufs_readwrite.c,v 1.30 1997/08/25 08:18:39 kato Exp $
  */
 
 #ifdef LFS_READWRITE
@@ -123,7 +123,7 @@ READ(ap)
 #else
 		if (lblktosize(fs, nextlbn) >= ip->i_size)
 			error = bread(vp, lbn, size, NOCRED, &bp);
-		else if (ffs_doclusterread)
+		else if ((vp->v_mount->mnt_flag & MNT_NOCLUSTERR) == 0)
 			error = cluster_read(vp, ip->i_size, lbn,
 				size, NOCRED, uio->uio_resid, seqcount, &bp);
 		else if (lbn - 1 == vp->v_lastr) {
@@ -281,7 +281,7 @@ WRITE(ap)
 		if (ioflag & IO_SYNC) {
 			(void)bwrite(bp);
 		} else if (xfersize + blkoffset == fs->fs_bsize) {
-			if (ffs_doclusterwrite) {
+			if ((vp->v_mount->mnt_flag & MNT_NOCLUSTERW) == 0) {
 				bp->b_flags |= B_CLUSTEROK;
 				cluster_write(bp, ip->i_size);
 			} else {