[PARISC] Further work for multiple page sizes

More work towards supporing multiple page sizes on 64-bit. Convert
some assumptions that 64bit uses 3 level page tables into testing
PT_NLEVELS. Also some BUG() to BUG_ON() conversions and some cleanups
to assembler.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index 3796be6..6317125 100644
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -6,6 +6,7 @@
  *    changed by Philipp Rumpf
  *  Copyright 1999 Philipp Rumpf (prumpf@tux.org)
  *  Copyright 2004 Randolph Chung (tausq@debian.org)
+ *  Copyright 2006 Helge Deller (deller@gmx.de)
  *
  */
 
@@ -371,8 +372,8 @@
 
 void free_initmem(void)
 {
-	unsigned long addr;
-	
+	unsigned long addr, init_begin, init_end;
+
 	printk(KERN_INFO "Freeing unused kernel memory: ");
 
 #ifdef CONFIG_DEBUG_KERNEL
@@ -395,8 +396,11 @@
 	local_irq_enable();
 #endif
 	
-	addr = (unsigned long)(&__init_begin);
-	for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
+	/* align __init_begin and __init_end to page size,
+	   ignoring linker script where we might have tried to save RAM */
+	init_begin = PAGE_ALIGN((unsigned long)(&__init_begin));
+	init_end   = PAGE_ALIGN((unsigned long)(&__init_end));
+	for (addr = init_begin; addr < init_end; addr += PAGE_SIZE) {
 		ClearPageReserved(virt_to_page(addr));
 		init_page_count(virt_to_page(addr));
 		free_page(addr);
@@ -407,7 +411,7 @@
 	/* set up a new led state on systems shipped LED State panel */
 	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE);
 	
-	printk("%luk freed\n", (unsigned long)(&__init_end - &__init_begin) >> 10);
+	printk("%luk freed\n", (init_end - init_begin) >> 10);
 }
 
 
@@ -639,11 +643,13 @@
 				 * Map the fault vector writable so we can
 				 * write the HPMC checksum.
 				 */
+#if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
 				if (address >= ro_start && address < ro_end
 							&& address != fv_addr
 							&& address != gw_addr)
 				    pte = __mk_pte(address, PAGE_KERNEL_RO);
 				else
+#endif
 				    pte = __mk_pte(address, pgprot);
 
 				if (address >= end_paddr)
@@ -874,8 +880,7 @@
 			flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
 			spin_lock(&sid_lock);
 		}
-		if (free_space_ids == 0)
-			BUG();
+		BUG_ON(free_space_ids == 0);
 	}
 
 	free_space_ids--;
@@ -899,8 +904,7 @@
 
 	spin_lock(&sid_lock);
 
-	if (*dirty_space_offset & (1L << index))
-	    BUG(); /* attempt to free space id twice */
+	BUG_ON(*dirty_space_offset & (1L << index)); /* attempt to free space id twice */
 
 	*dirty_space_offset |= (1L << index);
 	dirty_space_ids++;
@@ -975,7 +979,7 @@
 
 static unsigned long recycle_ndirty;
 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
-static unsigned int recycle_inuse = 0;
+static unsigned int recycle_inuse;
 
 void flush_tlb_all(void)
 {
@@ -984,9 +988,7 @@
 	do_recycle = 0;
 	spin_lock(&sid_lock);
 	if (dirty_space_ids > RECYCLE_THRESHOLD) {
-	    if (recycle_inuse) {
-		BUG();  /* FIXME: Use a semaphore/wait queue here */
-	    }
+	    BUG_ON(recycle_inuse);  /* FIXME: Use a semaphore/wait queue here */
 	    get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
 	    recycle_inuse++;
 	    do_recycle++;