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, 2 deletions

diff --git a/sys/vm/swap_pager.c b/sys/vm/swap_pager.c
index 4e8174b..31b632a 100644
--- a/sys/vm/swap_pager.c
+++ b/sys/vm/swap_pager.c
@@ -1592,7 +1592,7 @@ swp_pager_async_iodone(bp)
 			 * valid bits here, it is up to the caller.
 			 */
 
-			pmap_clear_modify(VM_PAGE_TO_PHYS(m));
+			pmap_clear_modify(m);
 			m->valid = VM_PAGE_BITS_ALL;
 			vm_page_undirty(m);
 			vm_page_flag_clear(m, PG_ZERO);
@@ -1618,7 +1618,7 @@ swp_pager_async_iodone(bp)
 			 * busy count and possibly wakes waiter's up ).
 			 */
 			vm_page_protect(m, VM_PROT_READ);
-			pmap_clear_modify(VM_PAGE_TO_PHYS(m));
+			pmap_clear_modify(m);
 			vm_page_undirty(m);
 			vm_page_io_finish(m);
 		}