PERFORCE change 30685 for review

[Marcel Moolenaar]

http://perforce.freebsd.org/chv.cgi?CH=30685

Change 30685 by marcel at marcel_nfs on 2003/05/06 19:56:03

	pmap_growkernel:
	o  Turn this function into a critical section.
	o  Move initialization of kernel_vm_end to pmap_bootstrap()
	   to avoid having to do it here.
	o  Don't further adjust kernel_vm_end by looking at the
	   page table directory entry, as if we cannot trust the
	   value.
	
	pmap_install:
	o  Do not treat kernel maps differently by not installing
	   them. This breaks the common usage of temporarily installing
	   a new map and then switch back again if the original map
	   is the kernel map.
	o  Clear the pm_active bit for this CPU on the old map, not
	   the new map. Hence, we never cleared pm_active...

Affected files ...

.. //depot/projects/ia64_epc/sys/ia64/ia64/pmap.c#9 edit

Differences ...

==== //depot/projects/ia64_epc/sys/ia64/ia64/pmap.c#9 (text+ko) ====

@@ -354,6 +354,7 @@
 		ia64_kptdir[i] = (void*)pmap_steal_memory(PAGE_SIZE);
 	}
 	nkpt = NKPT;
+	kernel_vm_end = NKPT * PAGE_SIZE * NKPTEPG + VM_MIN_KERNEL_ADDRESS;
 
 	avail_start = phys_avail[0];
 	for (i = 0; phys_avail[i+2]; i+= 2) ;
@@ -875,40 +876,30 @@
 	struct ia64_lpte *ptepage;
 	vm_page_t nkpg;
 
-	if (kernel_vm_end == 0) {
-		kernel_vm_end = nkpt * PAGE_SIZE * NKPTEPG
-		    + VM_MIN_KERNEL_ADDRESS;
-	}
-	addr = (addr + PAGE_SIZE * NKPTEPG) & ~(PAGE_SIZE * NKPTEPG - 1);
+	if (kernel_vm_end >= addr)
+		return;
+
+	critical_enter();
+
 	while (kernel_vm_end < addr) {
-		if (ia64_kptdir[KPTE_DIR_INDEX(kernel_vm_end)]) {
-			kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NKPTEPG)
-				& ~(PAGE_SIZE * NKPTEPG - 1);
-			continue;
-		}
-
-		/*
-		 * We could handle more by increasing the size of kptdir.
-		 */
+		/* We could handle more by increasing the size of kptdir. */
 		if (nkpt == MAXKPT)
 			panic("pmap_growkernel: out of kernel address space");
 
-		/*
-		 * This index is bogus, but out of the way
-		 */
 		nkpg = vm_page_alloc(NULL, nkpt,
 		    VM_ALLOC_NOOBJ | VM_ALLOC_SYSTEM | VM_ALLOC_WIRED);
 		if (!nkpg)
 			panic("pmap_growkernel: no memory to grow kernel");
-
-		nkpt++;
 		ptepage = (struct ia64_lpte *)
-			IA64_PHYS_TO_RR7(VM_PAGE_TO_PHYS(nkpg));
+		    IA64_PHYS_TO_RR7(VM_PAGE_TO_PHYS(nkpg));
 		bzero(ptepage, PAGE_SIZE);
 		ia64_kptdir[KPTE_DIR_INDEX(kernel_vm_end)] = ptepage;
 
-		kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NKPTEPG) & ~(PAGE_SIZE * NKPTEPG - 1);
+		nkpt++;
+		kernel_vm_end += PAGE_SIZE * NKPTEPG;
 	}
+
+	critical_exit();
 }
 
 /***************************************************
@@ -1171,9 +1162,9 @@
 pmap_find_kpte(vm_offset_t va)
 {
 	KASSERT((va >> 61) == 5,
-		("kernel mapping 0x%lx not in region 5", va));
+	    ("kernel mapping 0x%lx not in region 5", va));
 	KASSERT(IA64_RR_MASK(va) < (nkpt * PAGE_SIZE * NKPTEPG),
-		("kernel mapping 0x%lx out of range", va));
+	    ("kernel mapping 0x%lx out of range", va));
 	return (&ia64_kptdir[KPTE_DIR_INDEX(va)][KPTE_PTE_INDEX(va)]);
 }
 
@@ -2531,39 +2522,37 @@
 	critical_enter();
 
 	oldpmap = PCPU_GET(current_pmap);
-
-	if (pmap == oldpmap || pmap == kernel_pmap) {
+	if (oldpmap == pmap) {
 		critical_exit();
-		return pmap;
+		return (oldpmap);
 	}
 
-	if (oldpmap) {
-		atomic_clear_32(&pmap->pm_active, PCPU_GET(cpumask));
-	}
+	if (oldpmap != NULL)
+		atomic_clear_32(&oldpmap->pm_active, PCPU_GET(cpumask));
 
 	PCPU_SET(current_pmap, pmap);
-	if (!pmap) {
-		/*
-		 * RIDs 0..4 have no mappings to make sure we generate 
-		 * page faults on accesses.
-		 */
+
+	if (pmap == NULL) {
+		/* Invalidate regions 0-4. */
 		ia64_set_rr(IA64_RR_BASE(0), (0 << 8)|(PAGE_SHIFT << 2)|1);
 		ia64_set_rr(IA64_RR_BASE(1), (1 << 8)|(PAGE_SHIFT << 2)|1);
 		ia64_set_rr(IA64_RR_BASE(2), (2 << 8)|(PAGE_SHIFT << 2)|1);
 		ia64_set_rr(IA64_RR_BASE(3), (3 << 8)|(PAGE_SHIFT << 2)|1);
 		ia64_set_rr(IA64_RR_BASE(4), (4 << 8)|(PAGE_SHIFT << 2)|1);
 		critical_exit();
-		return oldpmap;
+		return (oldpmap);
 	}
 
 	atomic_set_32(&pmap->pm_active, PCPU_GET(cpumask));
 
-	for (i = 0; i < 5; i++)
+	for (i = 0; i < 5; i++) {
 		ia64_set_rr(IA64_RR_BASE(i),
-			    (pmap->pm_rid[i] << 8)|(PAGE_SHIFT << 2)|1);
+		    (pmap->pm_rid[i] << 8)|(PAGE_SHIFT << 2)|1);
+	}
 
 	critical_exit();
-	return oldpmap;
+
+	return (oldpmap);
 }
 
 vm_offset_t