Divorce "dev_t" from the "major|minor" bitmap, which is now called

udev_t in the kernel but still called dev_t in userland.

Provide functions to manipulate both types:
        major()         umajor()
        minor()         uminor()
        makedev()       umakedev()
        dev2udev()      udev2dev()

For now they're functions, they will become in-line functions
after one of the next two steps in this process.

Return major/minor/makedev to macro-hood for userland.

Register a name in cdevsw[] for the "filedescriptor" driver.

In the kernel the udev_t appears in places where we have the
major/minor number combination, (ie: a potential device: we
may not have the driver nor the device), like in inodes, vattr,
cdevsw registration and so on, whereas the dev_t appears where
we carry around a reference to a actual device.

In the future the cdevsw and the aliased-from vnode will be hung
directly from the dev_t, along with up to two softc pointers for
the device driver and a few houskeeping bits.  This will essentially
replace the current "alias" check code (same buck, bigger bang).

A little stunt has been provided to try to catch places where the
wrong type is being used (dev_t vs udev_t), if you see something
not working, #undef DEVT_FASCIST in kern/kern_conf.c and see if
it makes a difference.  If it does, please try to track it down
(many hands make light work) or at least try to reproduce it
as simply as possible, and describe how to do that.

Without DEVT_FASCIST I belive this patch is a no-op.

Stylistic/posixoid comments about the userland view of the <sys/*.h>
files welcome now, from userland they now contain the end result.

Next planned step: make all dev_t's refer to the same devsw[] which
means convert BLK's to CHR's at the perimeter of the vnodes and
other places where they enter the game (bootdev, mknod, sysctl).

1 files changed, 4 insertions, 4 deletions

diff --git a/sys/vm/device_pager.c b/sys/vm/device_pager.c
index c8e241a..997667d 100644
--- a/sys/vm/device_pager.c
+++ b/sys/vm/device_pager.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)device_pager.c	8.1 (Berkeley) 6/11/93
- * $Id: device_pager.c,v 1.39 1999/01/24 02:32:14 dillon Exp $
+ * $Id: device_pager.c,v 1.40 1999/05/08 06:40:29 phk Exp $
  */
 
 #include <sys/param.h>
@@ -103,7 +103,7 @@ dev_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t fo
 	/*
 	 * Make sure this device can be mapped.
 	 */
-	dev = (dev_t) (uintptr_t) handle;
+	dev = udev2dev((uintptr_t) handle, 2);
 	mapfunc = devsw(dev)->d_mmap;
 	if (mapfunc == NULL || mapfunc == (d_mmap_t *)nullop) {
 		printf("obsolete map function %p\n", (void *)mapfunc);
@@ -199,7 +199,7 @@ dev_pager_getpages(object, m, count, reqpage)
 	d_mmap_t *mapfunc;
 	int prot;
 
-	dev = (dev_t) (uintptr_t) object->handle;
+	dev = udev2dev((uintptr_t) object->handle, 2);
 	offset = m[reqpage]->pindex;
 	prot = PROT_READ;	/* XXX should pass in? */
 	mapfunc = devsw(dev)->d_mmap;
@@ -207,7 +207,7 @@ dev_pager_getpages(object, m, count, reqpage)
 	if (mapfunc == NULL || mapfunc == (d_mmap_t *)nullop)
 		panic("dev_pager_getpage: no map function");
 
-	paddr = pmap_phys_address((*mapfunc) ((dev_t) dev, (vm_offset_t) offset << PAGE_SHIFT, prot));
+	paddr = pmap_phys_address((*mapfunc) (dev, (vm_offset_t) offset << PAGE_SHIFT, prot));
 	KASSERT(paddr != -1,("dev_pager_getpage: map function returns error"));
 	/*
 	 * Replace the passed in reqpage page with our own fake page and free up the