Bring back PHYSLOAD_DEVICE for uvm_page_physload.

ok kettenis@ beck@ (tentatively) and ariane@. deraadt asked for it to be
commited now.

original commit message:

	extend uvm_page_physload to have the ability to add "device" pages to
	the system.

	This is needed in the case where you need managed pages so you can
	handle faulting and pmap_page_protect() on said pages when you manage
	memory in such regions (i'm looking at you, graphics cards).

	these pages are flagged PG_DEV, and shall never be on the freelists,
	assert this. behaviour remains unchanged in the non-device case,
	specifically for all archs currently in the tree we panic if called
	after bootstrap.

	ok art@ kettenis@, beck@

1 files changed, 34 insertions, 21 deletions

diff --git a/sys/uvm/uvm_page.c b/sys/uvm/uvm_page.c
index 72bbce4a874..7e95c431d18 100644
--- a/sys/uvm/uvm_page.c
+++ b/sys/uvm/uvm_page.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_page.c,v 1.97 2009/10/14 17:53:30 beck Exp $	*/
+/*	$OpenBSD: uvm_page.c,v 1.98 2010/03/24 00:36:04 oga Exp $	*/
 /*	$NetBSD: uvm_page.c,v 1.44 2000/11/27 08:40:04 chs Exp $	*/
 
 /* 
@@ -575,8 +575,8 @@ uvm_page_physget(paddr_t *paddrp)
  */
 
 void
-uvm_page_physload(paddr_t start, paddr_t end, paddr_t avail_start,
-    paddr_t avail_end, int free_list)
+uvm_page_physload_flags(paddr_t start, paddr_t end, paddr_t avail_start,
+    paddr_t avail_end, int free_list, int flags)
 {
 	int preload, lcv;
 	psize_t npages;
@@ -618,32 +618,46 @@ uvm_page_physload(paddr_t start, paddr_t end, paddr_t avail_start,
 	 * if VM is already running, attempt to malloc() vm_page structures
 	 */
 	if (!preload) {
-#if defined(VM_PHYSSEG_NOADD)
-		panic("uvm_page_physload: tried to add RAM after vm_mem_init");
-#else
-		/* XXXCDC: need some sort of lockout for this case */
-		paddr_t paddr;
-		npages = end - start;  /* # of pages */
-		pgs = (vm_page *)uvm_km_zalloc(kernel_map,
-		    sizeof(struct vm_page) * npages);
+		/*
+		 * XXXCDC: need some sort of lockout for this case
+		 * right now it is only used by devices so it should be alright.
+		 */
+ 		paddr_t paddr;
+
+ 		npages = end - start;  /* # of pages */
+
+		pgs = (struct vm_page *)uvm_km_zalloc(kernel_map,
+		    npages * sizeof(*pgs));
 		if (pgs == NULL) {
 			printf("uvm_page_physload: can not malloc vm_page "
 			    "structs for segment\n");
 			printf("\tignoring 0x%lx -> 0x%lx\n", start, end);
 			return;
 		}
-		/* init phys_addr and free_list, and free pages */
-		for (lcv = 0, paddr = ptoa(start) ;
-				 lcv < npages ; lcv++, paddr += PAGE_SIZE) {
+		/* init phys_addr and free pages, XXX uvmexp.npages */
+		for (lcv = 0, paddr = ptoa(start); lcv < npages;
+		    lcv++, paddr += PAGE_SIZE) {
 			pgs[lcv].phys_addr = paddr;
-			pgs[lcv].free_list = free_list;
+#ifdef __HAVE_VM_PAGE_MD
+			VM_MDPAGE_INIT(&pgs[lcv]);
+#endif
 			if (atop(paddr) >= avail_start &&
-			    atop(paddr) <= avail_end)
-				uvm_pagefree(&pgs[lcv]);
+			    atop(paddr) <= avail_end) {
+				if (flags & PHYSLOAD_DEVICE) {
+					atomic_setbits_int(&pgs[lcv].pg_flags,
+					    PG_DEV);
+					pgs[lcv].wire_count = 1;
+				} else {
+#if defined(VM_PHYSSEG_NOADD)
+		panic("uvm_page_physload: tried to add RAM after vm_mem_init");
+#else
+					uvm_pagefree(&pgs[lcv]);
+#endif
+				}
+			}
 		}
 		/* XXXCDC: incomplete: need to update uvmexp.free, what else? */
 		/* XXXCDC: need hook to tell pmap to rebuild pv_list, etc... */
-#endif
 	} else {
 
 		/* gcc complains if these don't get init'd */
@@ -901,14 +915,12 @@ uvm_pagealloc_strat(struct uvm_object *obj, voff_t off, struct vm_anon *anon,
 	pg->offset = off;
 	pg->uobject = obj;
 	pg->uanon = anon;
+	KASSERT((pg->pg_flags & PG_DEV) == 0);
 	pg->pg_flags = PG_BUSY|PG_CLEAN|PG_FAKE;
 	pg->pg_version++;
 	if (anon) {
 		anon->an_page = pg;
 		atomic_setbits_int(&pg->pg_flags, PQ_ANON);
-#ifdef UBC
-		uvm_pgcnt_anon++;
-#endif
 	} else {
 		if (obj)
 			uvm_pageinsert(pg);
@@ -996,6 +1008,7 @@ uvm_pagefree(struct vm_page *pg)
 
 	UVMHIST_LOG(pghist, "freeing pg %p/%lx", pg,
 	    (u_long)VM_PAGE_TO_PHYS(pg), 0, 0);
+	KASSERT((pg->pg_flags & PG_DEV) == 0);
 
 	/*
 	 * if the page was an object page (and thus "TABLED"), remove it