Implement an optimization of the VM<->pmap API. Pass vm_page_t's directly

to various pmap_*() functions instead of looking up the physical address
and passing that.  In many cases, the first thing the pmap code was doing
was going to a lot of trouble to get back the original vm_page_t, or
it's shadow pv_table entry.

Inspired by: John Dyson's 1998 patches.

Also:
Eliminate pv_table as a seperate thing and build it into a machine
dependent part of vm_page_t.  This eliminates having a seperate set of
structions that shadow each other in a 1:1 fashion that we often went to
a lot of trouble to translate from one to the other. (see above)
This happens to save 4 bytes of physical memory for each page in the
system.  (8 bytes on the Alpha).

Eliminate the use of the phys_avail[] array to determine if a page is
managed (ie: it has pv_entries etc).  Store this information in a flag.
Things like device_pager set it because they create vm_page_t's on the
fly that do not have pv_entries.  This makes it easier to "unmanage" a
page of physical memory (this will be taken advantage of in subsequent
commits).

Add a function to add a new page to the freelist.  This could be used
for reclaiming the previously wasted pages left over from preloaded
loader(8) files.

Reviewed by:	dillon

1 files changed, 2 insertions, 5 deletions

diff --git a/sys/amd64/amd64/mem.c b/sys/amd64/amd64/mem.c
index 21e7b3f..38cc24b 100644
--- a/sys/amd64/amd64/mem.c
+++ b/sys/amd64/amd64/mem.c
@@ -176,16 +176,13 @@ mmrw(dev, uio, flags)
 /* minor device 0 is physical memory */
 		case 0:
 			v = uio->uio_offset;
-			pmap_enter(kernel_pmap, (vm_offset_t)ptvmmap, v,
-				uio->uio_rw == UIO_READ ? VM_PROT_READ : VM_PROT_WRITE,
-				TRUE);
+			pmap_kenter((vm_offset_t)ptvmmap, v);
 			o = (int)uio->uio_offset & PAGE_MASK;
 			c = (u_int)(PAGE_SIZE - ((int)iov->iov_base & PAGE_MASK));
 			c = min(c, (u_int)(PAGE_SIZE - o));
 			c = min(c, (u_int)iov->iov_len);
 			error = uiomove((caddr_t)&ptvmmap[o], (int)c, uio);
-			pmap_remove(kernel_pmap, (vm_offset_t)ptvmmap,
-				    (vm_offset_t)&ptvmmap[PAGE_SIZE]);
+			pmap_kremove((vm_offset_t)ptvmmap);
 			continue;
 
 /* minor device 1 is kernel memory */