Implement pmap_growkernel. From NetBSD.

2 files changed, 113 insertions, 6 deletions

diff --git a/sys/arch/alpha/alpha/pmap.c b/sys/arch/alpha/alpha/pmap.c
index b9a8aeec24a..4820d12bca1 100644
--- a/sys/arch/alpha/alpha/pmap.c
+++ b/sys/arch/alpha/alpha/pmap.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: pmap.c,v 1.9 2001/03/04 13:37:44 art Exp $ */
+/* $OpenBSD: pmap.c,v 1.10 2001/03/16 09:06:03 art Exp $ */
 /* $NetBSD: pmap.c,v 1.132 2000/05/23 05:12:54 thorpej Exp $ */
 
 /*-
@@ -379,6 +379,9 @@ u_long	pmap_asn_generation[ALPHA_MAXPROCS]; /* current ASN generation */
  *	  all pmaps.  Note that a pm_slock must never be held while this
  *	  lock is held.
  *
+ *	* pmap_growkernel_slock - This lock protects pmap_growkernel()
+ *	  and the virtual_end variable.
+ *
  *	Address space number management (global ASN counters and per-pmap
  *	ASN state) are not locked; they use arrays of values indexed
  *	per-processor.
@@ -389,6 +392,7 @@ u_long	pmap_asn_generation[ALPHA_MAXPROCS]; /* current ASN generation */
  */
 struct lock pmap_main_lock;
 struct simplelock pmap_all_pmaps_slock;
+struct simplelock pmap_growkernel_slock;
 
 #ifdef __OpenBSD__
 #define spinlockinit(lock, name, flags)  lockinit(lock, 0, name, 0, flags)
@@ -876,6 +880,9 @@ pmap_bootstrap(ptaddr, maxasn, ncpuids)
 		    (i*PAGE_SIZE*NPTEPG))] = pte;
 	}
 
+	/* Initialize the pmap_growkernel_slock. */
+	simple_lock_init(&pmap_growkernel_slock);
+
 	/*
 	 * Set up level three page table (lev3map)
 	 */
@@ -889,7 +896,7 @@ pmap_bootstrap(ptaddr, maxasn, ncpuids)
 	avail_start = ptoa(vm_physmem[0].start);
 	avail_end = ptoa(vm_physmem[vm_nphysseg - 1].end);
 	virtual_avail = VM_MIN_KERNEL_ADDRESS;
-	virtual_end = VM_MIN_KERNEL_ADDRESS + lev3mapsize * NBPG;
+	virtual_end = VM_MIN_KERNEL_ADDRESS + lev3mapsize * PAGE_SIZE;
 
 #if 0
 	printf("avail_start = 0x%lx\n", avail_start);
@@ -1088,7 +1095,7 @@ pmap_steal_memory(size, vstartp, vendp)
 		if (vstartp)
 			*vstartp = round_page(virtual_avail);
 		if (vendp)
-			*vendp = trunc_page(virtual_end);
+			*vendp = VM_MAX_KERNEL_ADDRESS;
 
 		va = ALPHA_PHYS_TO_K0SEG(pa);
 		bzero((caddr_t)va, size);
@@ -3390,9 +3397,108 @@ pmap_physpage_delref(kva)
  *
  *	Grow the kernel address space.  This is a hint from the
  *	upper layer to pre-allocate more kernel PT pages.
- *
- *	XXX Implement XXX
  */
+vaddr_t
+pmap_growkernel(vaddr_t maxkvaddr)
+{
+	struct pmap *kpm = pmap_kernel(), *pm;
+	paddr_t ptaddr;
+	pt_entry_t *l1pte, *l2pte, pte;
+	vaddr_t va;
+	int s, l1idx;
+
+	if (maxkvaddr <= virtual_end)
+		goto out;		/* we are OK */
+
+	s = splhigh();			/* to be safe */
+	simple_lock(&pmap_growkernel_slock);
+
+	va = virtual_end;
+
+	while (va < maxkvaddr) {
+		/*
+		 * If there is no valid L1 PTE (i.e. no L2 PT page),
+		 * allocate a new L2 PT page and insert it into the
+		 * L1 map.
+		 */
+		l1pte = pmap_l1pte(kpm, va);
+		if (pmap_pte_v(l1pte) == 0) {
+			/*
+			 * XXX PGU_NORMAL?  It's not a "traditional" PT page.
+			 */
+#ifdef notyet
+			if (uvm.page_init_done == FALSE) {
+#else
+			if (vm_physmem[0].pgs == NULL) {
+#endif
+				/*
+				 * We're growing the kernel pmap early (from
+				 * uvm_pageboot_alloc()).  This case must
+				 * be handled a little differently.
+				 */
+				ptaddr = ALPHA_K0SEG_TO_PHYS(
+				    pmap_steal_memory(PAGE_SIZE, NULL, NULL));
+			} else if (pmap_physpage_alloc(PGU_NORMAL,
+				   &ptaddr) == FALSE)
+				goto die;
+			pte = (atop(ptaddr) << PG_SHIFT) |
+			    PG_V | PG_ASM | PG_KRE | PG_KWE | PG_WIRED;
+			*l1pte = pte;
+
+			l1idx = l1pte_index(va);
+
+			/* Update all the user pmaps. */
+			simple_lock(&pmap_all_pmaps_slock);
+			for (pm = TAILQ_FIRST(&pmap_all_pmaps);
+			     pm != NULL; pm = TAILQ_NEXT(pm, pm_list)) {
+				/* Skip the kernel pmap. */
+				if (pm == pmap_kernel())
+					continue;
+
+				PMAP_LOCK(pm);
+				if (pm->pm_lev1map == kernel_lev1map) {
+					PMAP_UNLOCK(pm);
+					continue;
+				}
+				pm->pm_lev1map[l1idx] = pte;
+				PMAP_UNLOCK(pm);
+			}
+			simple_unlock(&pmap_all_pmaps_slock);
+		}
+
+		/*
+		 * Have an L2 PT page now, add the L3 PT page.
+		 */
+		l2pte = pmap_l2pte(kpm, va, l1pte);
+		KASSERT(pmap_pte_v(l2pte) == 0);
+#ifdef notyet
+		if (uvm.page_init_done == FALSE) {
+#else
+		if (vm_physmem[0].pgs == NULL) {
+#endif
+			/*
+			 * See above.
+			 */
+			ptaddr = ALPHA_K0SEG_TO_PHYS(
+			    pmap_steal_memory(PAGE_SIZE, NULL, NULL));
+		} else if (pmap_physpage_alloc(PGU_NORMAL, &ptaddr) == FALSE)
+			goto die;
+		*l2pte = (atop(ptaddr) << PG_SHIFT) |
+		    PG_V | PG_ASM | PG_KRE | PG_KWE | PG_WIRED;
+		va += ALPHA_L2SEG_SIZE;
+	}
+
+	virtual_end = va;
+
+	simple_unlock(&pmap_growkernel_slock);
+	splx(s);
+
+ out:
+	return (virtual_end);
+
+ die:
+	panic("pmap_growkernel: out of memory");
+}
 
 /*
  * pmap_lev1map_create:
diff --git a/sys/arch/alpha/include/pmap.h b/sys/arch/alpha/include/pmap.h
index ad9aedf06b2..007931c4723 100644
--- a/sys/arch/alpha/include/pmap.h
+++ b/sys/arch/alpha/include/pmap.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: pmap.h,v 1.6 2000/11/08 21:27:21 ericj Exp $ */
+/* $OpenBSD: pmap.h,v 1.7 2001/03/16 09:06:02 art Exp $ */
 /* $NetBSD: pmap.h,v 1.35 2000/06/08 03:10:06 thorpej Exp $ */
 
 /*-
@@ -192,6 +192,7 @@ void	pmap_do_tlb_shootdown(void);
 extern	pt_entry_t *VPT;		/* Virtual Page Table */
 
 #define	PMAP_STEAL_MEMORY		/* enable pmap_steal_memory() */
+#define PMAP_GROWKERNEL			/* enable pmap_growkernel() */
 
 /*
  * Alternate mapping hooks for pool pages.  Avoids thrashing the TLB.