Revert a bunch of contraversial changes by PHK. After

a quick think and discussion among various people some form of some of
these changes will probably be recommitted.

The reversion requested was requested by dg while discussions proceed.
PHK has indicated that he can live with this, and it has been agreed
that some form of some of these changes may return shortly after further
discussion.

1 files changed, 33 insertions, 44 deletions

diff --git a/sys/miscfs/specfs/spec_vnops.c b/sys/miscfs/specfs/spec_vnops.c
index 8fd4539..1afc400 100644
--- a/sys/miscfs/specfs/spec_vnops.c
+++ b/sys/miscfs/specfs/spec_vnops.c
@@ -34,7 +34,6 @@
  * $FreeBSD$
  */
 
-#include "opt_fs.h"
 #include <sys/param.h>
 #include <sys/proc.h>
 #include <sys/systm.h>
@@ -47,7 +46,6 @@
 #include <sys/fcntl.h>
 #include <sys/disklabel.h>
 #include <sys/vmmeter.h>
-#include <sys/sysctl.h>
 
 #include <vm/vm.h>
 #include <vm/vm_prot.h>
@@ -235,15 +233,6 @@ spec_open(ap)
 	return (0);
 }
 
-#ifdef ALLOW_BDEV_ACCESS
-static int bdev_access = 1;
-#else
-static int bdev_access;
-#endif
-
-SYSCTL_INT(_vfs, OID_AUTO, bdev_access, CTLFLAG_RW, &bdev_access, 0,
-	"allow block device access");
-
 /*
  * Vnode op for read
  */
@@ -257,8 +246,8 @@ spec_read(ap)
 		struct ucred *a_cred;
 	} */ *ap;
 {
-	struct vnode *vp = ap->a_vp;
-	struct uio *uio = ap->a_uio;
+	register struct vnode *vp = ap->a_vp;
+	register struct uio *uio = ap->a_uio;
  	struct proc *p = uio->uio_procp;
 	struct buf *bp;
 	daddr_t bn, nextbn;
@@ -269,8 +258,6 @@ spec_read(ap)
 	int error = 0;
 	dev_t dev;
 
-	dev = vp->v_rdev;
-
 #ifdef DIAGNOSTIC
 	if (uio->uio_rw != UIO_READ)
 		panic("spec_read mode");
@@ -282,14 +269,24 @@ spec_read(ap)
 
 	switch (vp->v_type) {
 
+	case VCHR:
+		VOP_UNLOCK(vp, 0, p);
+		error = (*devsw(vp->v_rdev)->d_read)
+			(vp->v_rdev, uio, ap->a_ioflag);
+		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
+		return (error);
+
 	case VBLK:
-if (bdev_access) {
 		if (uio->uio_offset < 0)
 			return (EINVAL);
+		dev = vp->v_rdev;
 
-		bsize = dev->si_bsize_phys;
-		if (bsize < BLKDEV_IOSIZE)
-			bsize = BLKDEV_IOSIZE;
+		/*
+		 * Calculate block size for block device.  The block size must
+		 * be larger then the physical minimum.
+		 */
+
+		bsize = vp->v_rdev->si_bsize_best;
 
 		if ((ioctl = devsw(dev)->d_ioctl) != NULL &&
 		    (*ioctl)(dev, DIOCGPART, (caddr_t)&dpart, FREAD, p) == 0 &&
@@ -317,12 +314,6 @@ if (bdev_access) {
 			brelse(bp);
 		} while (error == 0 && uio->uio_resid > 0 && n != 0);
 		return (error);
-}
-	case VCHR:
-		VOP_UNLOCK(vp, 0, p);
-		error = (*devsw(dev)->d_read) (dev, uio, ap->a_ioflag);
-		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
-		return (error);
 
 	default:
 		panic("spec_read type");
@@ -343,8 +334,8 @@ spec_write(ap)
 		struct ucred *a_cred;
 	} */ *ap;
 {
-	struct vnode *vp = ap->a_vp;
-	struct uio *uio = ap->a_uio;
+	register struct vnode *vp = ap->a_vp;
+	register struct uio *uio = ap->a_uio;
 	struct proc *p = uio->uio_procp;
 	struct buf *bp;
 	daddr_t bn;
@@ -352,30 +343,36 @@ spec_write(ap)
 	struct partinfo dpart;
 	register int n, on;
 	int error = 0;
-	dev_t dev;
 
-	dev = vp->v_rdev;
 #ifdef DIAGNOSTIC
 	if (uio->uio_rw != UIO_WRITE)
 		panic("spec_write mode");
 	if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc)
 		panic("spec_write proc");
 #endif
-	if (uio->uio_resid == 0)
-		return (0);
 
 	switch (vp->v_type) {
 
+	case VCHR:
+		VOP_UNLOCK(vp, 0, p);
+		error = (*devsw(vp->v_rdev)->d_write)
+			(vp->v_rdev, uio, ap->a_ioflag);
+		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
+		return (error);
+
 	case VBLK:
-if (bdev_access) {
+		if (uio->uio_resid == 0)
+			return (0);
 		if (uio->uio_offset < 0)
 			return (EINVAL);
 
-		bsize = dev->si_bsize_phys;
-		if (bsize < BLKDEV_IOSIZE)
-			bsize = BLKDEV_IOSIZE;
+		/*
+		 * Calculate block size for block device.  The block size must
+		 * be larger then the physical minimum.
+		 */
+		bsize = vp->v_rdev->si_bsize_best;
 
-		if ((*devsw(dev)->d_ioctl)(dev, DIOCGPART,
+		if ((*devsw(vp->v_rdev)->d_ioctl)(vp->v_rdev, DIOCGPART,
 		    (caddr_t)&dpart, FREAD, p) == 0) {
 			if (dpart.part->p_fstype == FS_BSDFFS &&
 			    dpart.part->p_frag != 0 && dpart.part->p_fsize != 0)
@@ -403,14 +400,6 @@ if (bdev_access) {
 				bdwrite(bp);
 		} while (error == 0 && uio->uio_resid > 0 && n != 0);
 		return (error);
-}
-
-	case VCHR:
-		VOP_UNLOCK(vp, 0, p);
-		error = (*devsw(dev)->d_write)
-			(dev, uio, ap->a_ioflag);
-		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
-		return (error);
 
 	default:
 		panic("spec_write type");