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, 3 insertions, 3 deletions

diff --git a/sys/i386/include/pmap.h b/sys/i386/include/pmap.h
index 66b6b61..813f2ae 100644
--- a/sys/i386/include/pmap.h
+++ b/sys/i386/include/pmap.h
@@ -188,11 +188,11 @@ pmap_kextract(vm_offset_t va)
  * Pmap stuff
  */
 struct	pv_entry;
-typedef struct {
+
+struct md_page {
 	int pv_list_count;
-	struct vm_page		*pv_vm_page;
 	TAILQ_HEAD(,pv_entry)	pv_list;
-} pv_table_t;
+};
 
 struct pmap {
 	pd_entry_t		*pm_pdir;	/* KVA of page directory */