(1) fix incorrect virtual address calculation in kmap_atomic()
(2) more compilefixes for arch/i386/mm/highmem.c
(3) checking for alignment of kmap() and kmap_atomic() virtualspace
        in arch/i386/mm/init.c
(4) rework fixmap enums yet again so kmap() and kmap_atomic() areas
        actually come out properly aligned
(5) change FIXADDR_TOP to -PAGE_SIZE so the offset calculation isn't
        as easy to screw up
(6) fix mismerge of pgd_ctor() bits that installed garbage pmd's on
        CONFIG_HIGHMEM64G

diff -prauN pgcl-2.5.70-bk5-2/arch/i386/mm/highmem.c pgcl-2.5.70-bk5-3/arch/i386/mm/highmem.c
--- pgcl-2.5.70-bk5-2/arch/i386/mm/highmem.c	2003-06-01 23:44:38.000000000 -0700
+++ pgcl-2.5.70-bk5-3/arch/i386/mm/highmem.c	2003-06-01 23:45:12.000000000 -0700
@@ -43,7 +43,7 @@ void *kmap_atomic(struct page *page, enu
 		return page_address(page);
 
 	idx = type + KM_TYPE_NR*smp_processor_id();
-	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx*PAGE_SIZE);
+	vaddr = __fix_to_virt(FIX_KMAP_END) + PAGE_SIZE*idx;
 	WARN_ON(vaddr > __fix_to_virt(FIX_KMAP_BEGIN));
 	WARN_ON(vaddr < __fix_to_virt(FIX_KMAP_END));
 	pfn = page_to_pfn(page);
@@ -51,7 +51,7 @@ void *kmap_atomic(struct page *page, enu
 	pgd = pgd_offset_k(addr);
 	pmd = pmd_offset(pgd, addr);
 	pte = pte_offset_kernel(pmd, addr);
-	for (k = 0; k < PAGE_MMUCOUNT, ++k, addr += MMUPAGE_SIZE) {
+	for (k = 0; k < PAGE_MMUCOUNT; ++k, addr += MMUPAGE_SIZE) {
 #ifdef CONFIG_DEBUG_HIGHMEM
 		BUG_ON(!pte_none(pte[k]));
 #endif
@@ -77,10 +77,10 @@ void kunmap_atomic(void *kvaddr, enum km
 		return;
 	}
 
-	lo = __fix_to_virt(FIX_KMAP_END) + PAGE_SIZE * idx;
+	lo = __fix_to_virt(FIX_KMAP_END) + PAGE_SIZE*idx;
 	hi = lo + PAGE_SIZE;
 
-	BUG_ON(vaddr < lo || vaddr > hi);;
+	BUG_ON(vaddr < lo || vaddr > hi);
 
 	/*
 	 * force other mappings to Oops if they'll try to access
diff -prauN pgcl-2.5.70-bk5-2/arch/i386/mm/init.c pgcl-2.5.70-bk5-3/arch/i386/mm/init.c
--- pgcl-2.5.70-bk5-2/arch/i386/mm/init.c	2003-05-31 04:59:16.000000000 -0700
+++ pgcl-2.5.70-bk5-3/arch/i386/mm/init.c	2003-06-01 23:45:12.000000000 -0700
@@ -508,6 +508,24 @@ void __init mem_init(void)
 	printk("fixaddr: start = 0x%lx, end = 0x%lx\n",
 			FIXADDR_START, FIXADDR_TOP);
 
+#ifdef CONFIG_HIGHMEM
+	printk("FIX_KMAP_END == %lx\n", __fix_to_virt(FIX_KMAP_END));
+	if (__fix_to_virt(FIX_KMAP_END) % PAGE_SIZE)
+		printk(KERN_CRIT "kmap_atomic() area misaligned!\n");
+
+	printk("FIX_KMAP_BEGIN == %lx\n", __fix_to_virt(FIX_KMAP_BEGIN));
+	if ((__fix_to_virt(FIX_KMAP_BEGIN) + MMUPAGE_SIZE) % PAGE_SIZE)
+		printk(KERN_CRIT "kmap_atomic() area misaligned!\n");
+
+	printk("FIX_PKMAP_END == %lx\n", __fix_to_virt(FIX_PKMAP_END));
+	if (__fix_to_virt(FIX_PKMAP_END) % PAGE_SIZE)
+		printk(KERN_CRIT "kmap() area misaligned!\n");
+
+	printk("FIX_PKMAP_BEGIN == %lx\n", __fix_to_virt(FIX_PKMAP_BEGIN));
+	if ((__fix_to_virt(FIX_PKMAP_BEGIN) + MMUPAGE_SIZE) % PAGE_SIZE)
+		printk(KERN_CRIT "kmap() area misaligned!\n");
+#endif
+
 #ifdef CONFIG_X86_PAE
 	if (!cpu_has_pae)
 		panic("cannot execute a PAE-enabled kernel on a PAE-less CPU!");
diff -prauN pgcl-2.5.70-bk5-2/arch/i386/mm/pgtable.c pgcl-2.5.70-bk5-3/arch/i386/mm/pgtable.c
--- pgcl-2.5.70-bk5-2/arch/i386/mm/pgtable.c	2003-06-01 23:44:38.000000000 -0700
+++ pgcl-2.5.70-bk5-3/arch/i386/mm/pgtable.c	2003-06-01 23:50:38.000000000 -0700
@@ -240,7 +240,8 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
 		pmd_t *pmd = kmem_cache_alloc(pmd_cache, GFP_KERNEL);
 		if (!pmd)
 			goto out_oom;
-		set_pgd(&pgd[i], __pgd(1 + __pa((u64)(u32)__va(pgd_val(pgd[i])-1))));
+		else
+			set_pgd(&pgd[i], __pgd(1 + __pa(pmd)));
 	}
 	return pgd;
 
diff -prauN pgcl-2.5.70-bk5-2/include/asm-i386/fixmap.h pgcl-2.5.70-bk5-3/include/asm-i386/fixmap.h
--- pgcl-2.5.70-bk5-2/include/asm-i386/fixmap.h	2003-05-31 04:59:16.000000000 -0700
+++ pgcl-2.5.70-bk5-3/include/asm-i386/fixmap.h	2003-06-01 23:45:12.000000000 -0700
@@ -28,21 +28,19 @@
  * addresses. The point is to have a constant address at
  * compile time, but to set the physical address only
  * in the boot process. We allocate these special addresses
- * from the end of virtual memory (0xfffff000) backwards.
+ * from the end of virtual memory (-PAGE_SIZE) backwards.
  * Also this lets us do fail-safe vmalloc(), we
  * can guarantee that these special addresses and
  * vmalloc()-ed addresses never overlap.
  *
- * these 'compile-time allocated' memory buffers are
- * fixed-size 4k pages. (or larger if used with an increment
- * highger than 1) use fixmap_set(idx,phys) to associate
- * physical memory with fixmap indices.
+ * These 'compile-time allocated' memory buffers are
+ * fixed-size MMUPAGE_SIZE-size pages. Use
+ * set_fixmap(idx, phys, prot) to associate physical memory with
+ * fixmap indices.
  *
  * TLB entries of such buffers will not be flushed across
  * task switches.
- */
-
-/*
+ *
  * Right now we initialize only a single pte table. It can be extended
  * easily, subsequent pte tables have to be allocated in one physical
  * chunk of RAM.
@@ -52,14 +50,29 @@
 #define LAST_PKMAP	1024
 #define LAST_PKMAP_MASK	(LAST_PKMAP-1)
 
+/*
+ * FIXADDR stuff is used by highmem.c for kmapping, and various
+ * drivers for system devices for their io mappings.
+ *
+ * Leave one empty page between vmalloc'ed areas and
+ * the start of the fixmap.
+ *
+ * leave a hole of exactly PAGE_SIZE at the top for CONFIG_HIGHMEM
+ * this makes things easier on core code; the math works out funny
+ * and I didn't care enough to conserve PAGE_SIZE - MMUPAGE_SIZE
+ * worth of virtualspace.
+ */
+#define FIXADDR_TOP	(-PAGE_SIZE)
+#define __FIXADDR_SIZE	(__end_of_permanent_fixed_addresses << MMUPAGE_SHIFT)
+#define FIXADDR_START	(FIXADDR_TOP - __FIXADDR_SIZE)
+
+#define __fix_to_virt(x)	(FIXADDR_TOP - ((x) << MMUPAGE_SHIFT))
+#define __virt_to_fix(x)	((FIXADDR_TOP - ((x) & MMUPAGE_MASK)) >> MMUPAGE_SHIFT)
+
 enum fixed_addresses {
-	/*
-	 * leave a hole of exactly PAGE_SIZE at the top for CONFIG_HIGHMEM
-	 * this makes things easier on core code; the math works out funny
-	 */
-	FIX_HOLE = PAGE_MMUCOUNT > 1 ? PAGE_MMUCOUNT - 1 : 0,
 #ifdef CONFIG_HIGHMEM
-	FIX_KMAP_BEGIN,	/* reserved pte's for temporary kernel mappings */
+	/* reserved pte's for temporary kernel mappings */
+	FIX_KMAP_BEGIN = 1,
 	FIX_KMAP_END = FIX_KMAP_BEGIN+((KM_TYPE_NR*NR_CPUS+1)*PAGE_MMUCOUNT)-1,
 	FIX_PKMAP_BEGIN,
 	FIX_PKMAP_END = FIX_PKMAP_BEGIN + (LAST_PKMAP+1)*PAGE_MMUCOUNT - 1,
@@ -111,19 +124,6 @@ extern void __set_fixmap (enum fixed_add
 #define clear_fixmap(idx) \
 		__set_fixmap(idx, 0, __pgprot(0))
 
-/*
- * used by vmalloc.c.
- *
- * Leave one empty page between vmalloc'ed areas and
- * the start of the fixmap.
- */
-#define FIXADDR_TOP	(0xfffff000UL)
-#define __FIXADDR_SIZE	(__end_of_permanent_fixed_addresses << MMUPAGE_SHIFT)
-#define FIXADDR_START	(FIXADDR_TOP - __FIXADDR_SIZE)
-
-#define __fix_to_virt(x)	(FIXADDR_TOP - ((x) << MMUPAGE_SHIFT))
-#define __virt_to_fix(x)	((FIXADDR_TOP - ((x) & MMUPAGE_MASK)) >> MMUPAGE_SHIFT)
-
 extern void __this_fixmap_does_not_exist(void);
 
 /*