Import of Linux/MIPS 2.1.14

1 files changed, 1965 insertions, 0 deletions

diff --git a/arch/sparc/mm/sun4c.c b/arch/sparc/mm/sun4c.c
new file mode 100644
index 000000000..fdc74d3d7
--- /dev/null
+++ b/arch/sparc/mm/sun4c.c
@@ -0,0 +1,1965 @@
+/* $Id: sun4c.c,v 1.121 1996/11/01 20:36:27 ecd Exp $
+ * sun4c.c: Doing in software what should be done in hardware.
+ *
+ * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
+ * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
+ * Copyright (C) 1996 Andrew Tridgell (Andrew.Tridgell@anu.edu.au)
+ */
+
+#include <linux/kernel.h>
+#include <linux/mm.h>
+
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/vaddrs.h>
+#include <asm/idprom.h>
+#include <asm/machines.h>
+#include <asm/memreg.h>
+#include <asm/processor.h>
+#include <asm/auxio.h>
+#include <asm/io.h>
+#include <asm/oplib.h>
+#include <asm/openprom.h>
+
+extern int num_segmaps, num_contexts;
+
+/* Small structure for ease of handling in the low level kernel fault
+ * handler. This holds all information necessary, like the sun4c_ufree_ring
+ * for user segments.
+ */
+struct sun4c_segment_info {
+	unsigned long vaddr;
+	unsigned char pseg;
+};
+struct sun4c_segment_info *sun4c_kernel_next;
+
+#define SUN4C_KERNEL_BUCKETS 32
+#define SUN4C_KERNEL_BSIZE (sizeof(struct sun4c_segment_info) \
+			    * SUN4C_KERNEL_BUCKETS)
+
+#ifndef MAX
+#define MAX(a,b) ((a)<(b)?(b):(a))
+#endif
+#ifndef MIN
+#define MIN(a,b) ((a)<(b)?(a):(b))
+#endif
+
+
+
+#define KGPROF_PROFILING 0
+#if KGPROF_PROFILING
+#define KGPROF_DEPTH 3 /* this needs to match the code below */
+#define KGPROF_SIZE 100
+static struct {
+	unsigned addr[KGPROF_DEPTH];
+	unsigned count;
+} kgprof_counters[KGPROF_SIZE];
+
+/* just call this function from whatever function you think needs it then
+   look at /proc/cpuinfo to see where the function is being called from
+   and how often. This gives a type of "kernel gprof" */
+#define NEXT_PROF(prev,lvl) (prev>PAGE_OFFSET?__builtin_return_address(lvl):0)
+static inline void kgprof_profile(void)
+{
+	unsigned ret[KGPROF_DEPTH];
+	int i,j;
+	/* you can't use a variable argument to __builtin_return_address() */
+	ret[0] = (unsigned)__builtin_return_address(0);
+	ret[1] = (unsigned)NEXT_PROF(ret[0],1);
+	ret[2] = (unsigned)NEXT_PROF(ret[1],2);
+
+	for (i=0;i<KGPROF_SIZE && kgprof_counters[i].addr[0];i++) {
+		for (j=0;j<KGPROF_DEPTH;j++) 
+			if (ret[j] != kgprof_counters[i].addr[j]) break;
+		if (j==KGPROF_DEPTH) break;
+	}
+	if (i<KGPROF_SIZE) {		
+		for (j=0;j<KGPROF_DEPTH;j++)
+			kgprof_counters[i].addr[j] = ret[j];
+		kgprof_counters[i].count++;
+	}
+}
+#endif
+
+
+/* Flushing the cache. */
+struct sun4c_vac_props sun4c_vacinfo;
+static int ctxflushes, segflushes, pageflushes;
+
+/* convert a virtual address to a physical address and vice
+   versa. Easy on the 4c */
+static unsigned long sun4c_v2p(unsigned long vaddr)
+{
+  return(vaddr - PAGE_OFFSET);
+}
+
+static unsigned long sun4c_p2v(unsigned long vaddr)
+{
+  return(vaddr + PAGE_OFFSET);
+}
+
+
+/* Invalidate every sun4c cache line tag. */
+void sun4c_flush_all(void)
+{
+	unsigned long begin, end;
+
+	if(sun4c_vacinfo.on)
+		panic("SUN4C: AIEEE, trying to invalidate vac while"
+                      " it is on.");
+
+	/* Clear 'valid' bit in all cache line tags */
+	begin = AC_CACHETAGS;
+	end = (AC_CACHETAGS + sun4c_vacinfo.num_bytes);
+	while(begin < end) {
+		__asm__ __volatile__("sta %%g0, [%0] %1\n\t" : :
+				     "r" (begin), "i" (ASI_CONTROL));
+		begin += sun4c_vacinfo.linesize;
+	}
+}
+
+/* Blow the entire current context out of the virtual cache. */
+static inline void sun4c_flush_context(void)
+{
+	unsigned long vaddr;
+
+	ctxflushes++;
+	if(sun4c_vacinfo.do_hwflushes) {
+		for(vaddr=0; vaddr < sun4c_vacinfo.num_bytes; vaddr+=PAGE_SIZE)
+			__asm__ __volatile__("sta %%g0, [%0] %1\n\t" : :
+					     "r" (vaddr), "i" (ASI_HWFLUSHCONTEXT));
+	} else {
+		/* AJT: possibly read the tags and avoid flushing the ones that 
+		   are above 0xf0000000 so the kernel isn't flushed all the time */
+		__asm__ __volatile__("add	%1, %1, %%g1\n\t"
+				     "add	%1, %%g1, %%g2\n\t"
+				     "add	%1, %%g2, %%g3\n\t"
+				     "add	%1, %%g3, %%g4\n\t"
+				     "add	%1, %%g4, %%g5\n\t"
+				     "add	%1, %%g5, %%o4\n\t"
+				     "add	%1, %%o4, %%o5\n"
+				     "1:\n\t"
+				     "subcc	%0, %%o5, %0\n\t"
+				     "sta	%%g0, [%0] %2\n\t"
+				     "sta	%%g0, [%0 + %1] %2\n\t"
+				     "sta	%%g0, [%0 + %%g1] %2\n\t"
+				     "sta	%%g0, [%0 + %%g2] %2\n\t"
+				     "sta	%%g0, [%0 + %%g3] %2\n\t"
+				     "sta	%%g0, [%0 + %%g4] %2\n\t"
+				     "sta	%%g0, [%0 + %%g5] %2\n\t"
+				     "bg	1b\n\t"
+				     " sta	%%g0, [%0 + %%o4] %2\n\t" : :
+				     "r" (sun4c_vacinfo.num_bytes),
+				     "r" (sun4c_vacinfo.linesize),
+				     "i" (ASI_FLUSHCTX) :
+				     "g1", "g2", "g3", "g4", "g5", "o4", "o5");
+	}
+}
+
+/* Scrape the segment starting at ADDR from the virtual cache. */
+static inline void sun4c_flush_segment(unsigned long addr)
+{
+	segflushes++;
+	addr &= SUN4C_REAL_PGDIR_MASK;
+	if(sun4c_vacinfo.do_hwflushes) {
+		unsigned long end = (addr + sun4c_vacinfo.num_bytes);
+
+		for( ; addr < end; addr += PAGE_SIZE)
+			__asm__ __volatile__("sta %%g0, [%0] %1\n\t" : :
+					     "r" (addr), "i" (ASI_HWFLUSHSEG));
+	} else {
+		__asm__ __volatile__("add	%2, %2, %%g1\n\t"
+				     "add	%2, %%g1, %%g2\n\t"
+				     "add	%2, %%g2, %%g3\n\t"
+				     "add	%2, %%g3, %%g4\n\t"
+				     "add	%2, %%g4, %%g5\n\t"
+				     "add	%2, %%g5, %%o4\n\t"
+				     "add	%2, %%o4, %%o5\n"
+				     "1:\n\t"
+				     "subcc	%1, %%o5, %1\n\t"
+				     "sta	%%g0, [%0] %3\n\t"
+				     "sta	%%g0, [%0 + %2] %3\n\t"
+				     "sta	%%g0, [%0 + %%g1] %3\n\t"
+				     "sta	%%g0, [%0 + %%g2] %3\n\t"
+				     "sta	%%g0, [%0 + %%g3] %3\n\t"
+				     "sta	%%g0, [%0 + %%g4] %3\n\t"
+				     "sta	%%g0, [%0 + %%g5] %3\n\t"
+				     "sta	%%g0, [%0 + %%o4] %3\n\t"
+				     "bg	1b\n\t"
+				     " add	%0, %%o5, %0\n\t" : :
+				     "r" (addr), "r" (sun4c_vacinfo.num_bytes),
+				     "r" (sun4c_vacinfo.linesize),
+				     "i" (ASI_FLUSHSEG) :
+				     "g1", "g2", "g3", "g4", "g5", "o4", "o5");
+	}
+}
+
+/* Bolix one page from the virtual cache. */
+static inline void sun4c_flush_page(unsigned long addr)
+{
+	addr &= PAGE_MASK;
+
+	pageflushes++;
+	if(sun4c_vacinfo.do_hwflushes) {
+		__asm__ __volatile__("sta %%g0, [%0] %1\n\t" : :
+				     "r" (addr), "i" (ASI_HWFLUSHPAGE));
+	} else {
+		__asm__ __volatile__("add	%2, %2, %%g1\n\t"
+				     "add	%2, %%g1, %%g2\n\t"
+				     "add	%2, %%g2, %%g3\n\t"
+				     "add	%2, %%g3, %%g4\n\t"
+				     "add	%2, %%g4, %%g5\n\t"
+				     "add	%2, %%g5, %%o4\n\t"
+				     "add	%2, %%o4, %%o5\n"
+				     "1:\n\t"
+				     "subcc	%1, %%o5, %1\n\t"
+				     "sta	%%g0, [%0] %3\n\t"
+				     "sta	%%g0, [%0 + %2] %3\n\t"
+				     "sta	%%g0, [%0 + %%g1] %3\n\t"
+				     "sta	%%g0, [%0 + %%g2] %3\n\t"
+				     "sta	%%g0, [%0 + %%g3] %3\n\t"
+				     "sta	%%g0, [%0 + %%g4] %3\n\t"
+				     "sta	%%g0, [%0 + %%g5] %3\n\t"
+				     "sta	%%g0, [%0 + %%o4] %3\n\t"
+				     "bg	1b\n\t"
+				     " add	%0, %%o5, %0\n\t" : :
+				     "r" (addr), "r" (PAGE_SIZE),
+				     "r" (sun4c_vacinfo.linesize),
+				     "i" (ASI_FLUSHPG) :
+				     "g1", "g2", "g3", "g4", "g5", "o4", "o5");
+	}
+}
+
+/* The sun4c's do have an on chip store buffer.  And the way you
+ * clear them out isn't so obvious.  The only way I can think of
+ * to accomplish this is to read the current context register,
+ * store the same value there, then read an external hardware
+ * register.
+ */
+void sun4c_complete_all_stores(void)
+{
+	volatile int _unused;
+
+	_unused = sun4c_get_context();
+	sun4c_set_context(_unused);
+	_unused = *AUXREG;
+}
+
+/* Bootup utility functions. */
+static inline void sun4c_init_clean_segmap(unsigned char pseg)
+{
+	unsigned long vaddr;
+
+	sun4c_put_segmap(0, pseg);
+	for(vaddr = 0; vaddr < SUN4C_REAL_PGDIR_SIZE; vaddr+=PAGE_SIZE)
+		sun4c_put_pte(vaddr, 0);
+	sun4c_put_segmap(0, invalid_segment);
+}
+
+static inline void sun4c_init_clean_mmu(unsigned long kernel_end)
+{
+	unsigned long vaddr;
+	unsigned char savectx, ctx;
+
+	savectx = sun4c_get_context();
+	kernel_end = SUN4C_REAL_PGDIR_ALIGN(kernel_end);
+	for(ctx = 0; ctx < num_contexts; ctx++) {
+		sun4c_set_context(ctx);
+		for(vaddr = 0; vaddr < 0x20000000; vaddr += SUN4C_REAL_PGDIR_SIZE)
+			sun4c_put_segmap(vaddr, invalid_segment);
+		for(vaddr = 0xe0000000; vaddr < KERNBASE; vaddr += SUN4C_REAL_PGDIR_SIZE)
+			sun4c_put_segmap(vaddr, invalid_segment);
+		for(vaddr = kernel_end; vaddr < KADB_DEBUGGER_BEGVM; vaddr += SUN4C_REAL_PGDIR_SIZE)
+			sun4c_put_segmap(vaddr, invalid_segment);
+		for(vaddr = LINUX_OPPROM_ENDVM; vaddr; vaddr += SUN4C_REAL_PGDIR_SIZE)
+			sun4c_put_segmap(vaddr, invalid_segment);
+	}
+	sun4c_set_context(savectx);
+}
+
+void sun4c_probe_vac(void)
+{
+	sun4c_disable_vac();
+	sun4c_vacinfo.num_bytes = prom_getintdefault(prom_root_node,
+						     "vac-size", 65536);
+	sun4c_vacinfo.linesize = prom_getintdefault(prom_root_node,
+						    "vac-linesize", 16);
+	sun4c_vacinfo.num_lines =
+		(sun4c_vacinfo.num_bytes / sun4c_vacinfo.linesize);
+	switch(sun4c_vacinfo.linesize) {
+	case 16:
+		sun4c_vacinfo.log2lsize = 4;
+		break;
+	case 32:
+		sun4c_vacinfo.log2lsize = 5;
+		break;
+	default:
+		prom_printf("probe_vac: Didn't expect vac-linesize of %d, halting\n",
+			    sun4c_vacinfo.linesize);
+		prom_halt();
+	};
+
+	/* Only vac-hwflush (with a dash) is reliable, weitek
+	 * power-up processor claims vac_hwflush (underscore)
+	 * yet crashes if you try to use hardware based flushes.
+	 */
+	sun4c_vacinfo.do_hwflushes = prom_getintdefault(prom_root_node,
+							"vac-hwflush", 0);
+
+	if(sun4c_vacinfo.num_bytes != 65536) {
+		prom_printf("WEIRD Sun4C VAC cache size, tell davem");
+		prom_halt();
+	}
+
+	sun4c_flush_all();
+	sun4c_enable_vac();
+}
+
+/* Patch instructions for the low level kernel fault handler. */
+extern unsigned long invalid_segment_patch1, invalid_segment_patch1_ff;
+extern unsigned long invalid_segment_patch2, invalid_segment_patch2_ff;
+extern unsigned long num_context_patch1, num_context_patch1_16;
+extern unsigned long num_context_patch2, num_context_patch2_16;
+extern unsigned long sun4c_kernel_buckets_patch;
+extern unsigned long sun4c_kernel_buckets_patch_32;
+
+#define PATCH_INSN(src, dst) do {	\
+		daddr = &(dst);		\
+		iaddr = &(src);		\
+		*daddr = *iaddr;	\
+	} while (0);
+
+static void patch_kernel_fault_handler(void)
+{
+	unsigned long *iaddr, *daddr;
+
+	switch (num_segmaps) {
+		case 128:
+			/* Default, nothing to do. */
+			break;
+		case 256:
+			PATCH_INSN(invalid_segment_patch1_ff,
+				   invalid_segment_patch1);
+			PATCH_INSN(invalid_segment_patch2_ff,
+				   invalid_segment_patch2);
+			break;
+		default:
+			prom_printf("Unhandled number of segmaps: %d\n",
+				    num_segmaps);
+			prom_halt();
+	}
+	switch (num_contexts) {
+		case 8:
+			/* Default, nothing to do. */
+			break;
+		case 16:
+			PATCH_INSN(num_context_patch1_16,
+				   num_context_patch1);
+			PATCH_INSN(num_context_patch2_16,
+				   num_context_patch2);
+			break;
+		default:
+			prom_printf("Unhandled number of contexts: %d\n",
+				    num_contexts);
+			prom_halt();
+	}
+	switch (SUN4C_KERNEL_BUCKETS) {
+		case 16:
+			/* Default, nothing to do. */
+			break;
+		case 32:
+			PATCH_INSN(sun4c_kernel_buckets_patch_32,
+				   sun4c_kernel_buckets_patch);
+			break;
+		default:
+			prom_printf("Unhandled number of kernel buckets: %d\n",
+				    SUN4C_KERNEL_BUCKETS);
+			prom_halt();
+	}
+}
+
+static void sun4c_probe_mmu(void)
+{
+	num_segmaps = prom_getintdefault(prom_root_node, "mmu-npmg", 128);
+	num_contexts = prom_getintdefault(prom_root_node, "mmu-nctx", 0x8);
+	patch_kernel_fault_handler();
+}
+
+volatile unsigned long *sun4c_memerr_reg = 0;
+
+void sun4c_probe_memerr_reg(void)
+{
+	int node;
+	struct linux_prom_registers regs[1];
+
+	node = prom_getchild(prom_root_node);
+	node = prom_searchsiblings(prom_root_node, "memory-error");
+	if (!node)
+		return;
+	prom_getproperty(node, "reg", (char *)regs, sizeof(regs));
+	sun4c_memerr_reg = sparc_alloc_io(regs[0].phys_addr, 0,
+					  regs[0].reg_size,
+					  "memory parity error",
+					  regs[0].which_io, 0);
+}
+
+static inline void sun4c_init_ss2_cache_bug(void)
+{
+	extern unsigned long start;
+
+	if((idprom->id_machtype == (SM_SUN4C | SM_4C_SS2)) ||
+	   (idprom->id_machtype == (SM_SUN4C | SM_4C_IPX))) {
+		/* Whee.. */
+		printk("SS2 cache bug detected, uncaching trap table page\n");
+		sun4c_flush_page((unsigned int) &start);
+		sun4c_put_pte(((unsigned long) &start),
+			(sun4c_get_pte((unsigned long) &start) | _SUN4C_PAGE_NOCACHE));
+	}
+}
+
+/* Addr is always aligned on a page boundry for us already. */
+static void sun4c_map_dma_area(unsigned long addr, int len)
+{
+	unsigned long page, end;
+
+	end = PAGE_ALIGN((addr + len));
+	while(addr < end) {
+		page = get_free_page(GFP_KERNEL);
+		if(!page) {
+			prom_printf("alloc_dvma: Cannot get a dvma page\n");
+			prom_halt();
+		}
+		sun4c_flush_page(page);
+		page -= PAGE_OFFSET;
+		page >>= PAGE_SHIFT;
+		page |= (_SUN4C_PAGE_VALID | _SUN4C_PAGE_WRITE | _SUN4C_PAGE_NOCACHE);
+		sun4c_put_pte(addr, page);
+		addr += PAGE_SIZE;
+	}
+}
+
+
+/* TLB management. */
+struct sun4c_mmu_entry {
+	struct sun4c_mmu_entry *next;
+	struct sun4c_mmu_entry *prev;
+	unsigned long vaddr;
+	unsigned char pseg;
+	unsigned char locked;
+};
+static struct sun4c_mmu_entry mmu_entry_pool[256];
+
+static void sun4c_init_mmu_entry_pool(void)
+{
+	int i;
+
+	for(i=0; i < 256; i++) {
+		mmu_entry_pool[i].pseg = i;
+		mmu_entry_pool[i].next = 0;
+		mmu_entry_pool[i].prev = 0;
+		mmu_entry_pool[i].vaddr = 0;
+		mmu_entry_pool[i].locked = 0;
+	}
+	mmu_entry_pool[invalid_segment].locked = 1;
+}
+
+static inline void fix_permissions(unsigned long vaddr, unsigned long bits_on,
+				   unsigned long bits_off)
+{
+	unsigned long start, end;
+
+	end = vaddr + SUN4C_REAL_PGDIR_SIZE;
+	for(start = vaddr; start < end; start += PAGE_SIZE)
+		if(sun4c_get_pte(start) & _SUN4C_PAGE_VALID)
+			sun4c_put_pte(start, (sun4c_get_pte(start) | bits_on) &
+				      ~bits_off);
+}
+
+static inline void sun4c_init_map_kernelprom(unsigned long kernel_end)
+{
+	unsigned long vaddr;
+	unsigned char pseg, ctx;
+
+	for(vaddr = KADB_DEBUGGER_BEGVM;
+	    vaddr < LINUX_OPPROM_ENDVM;
+	    vaddr += SUN4C_REAL_PGDIR_SIZE) {
+		pseg = sun4c_get_segmap(vaddr);
+		if(pseg != invalid_segment) {
+			mmu_entry_pool[pseg].locked = 1;
+			for(ctx = 0; ctx < num_contexts; ctx++)
+				prom_putsegment(ctx, vaddr, pseg);
+			fix_permissions(vaddr, _SUN4C_PAGE_PRIV, 0);
+		}
+	}
+	for(vaddr = KERNBASE; vaddr < kernel_end; vaddr += SUN4C_REAL_PGDIR_SIZE) {
+		pseg = sun4c_get_segmap(vaddr);
+		mmu_entry_pool[pseg].locked = 1;
+		for(ctx = 0; ctx < num_contexts; ctx++)
+			prom_putsegment(ctx, vaddr, pseg);
+		fix_permissions(vaddr, _SUN4C_PAGE_PRIV, _SUN4C_PAGE_NOCACHE);
+	}
+}
+
+static void sun4c_init_lock_area(unsigned long start, unsigned long end)
+{
+	int i, ctx;
+
+	while(start < end) {
+		for(i=0; i < invalid_segment; i++)
+			if(!mmu_entry_pool[i].locked)
+				break;
+		mmu_entry_pool[i].locked = 1;
+		sun4c_init_clean_segmap(i);
+		for(ctx = 0; ctx < num_contexts; ctx++)
+			prom_putsegment(ctx, start, mmu_entry_pool[i].pseg);
+		start += SUN4C_REAL_PGDIR_SIZE;
+	}
+}
+
+struct sun4c_mmu_ring {
+	struct sun4c_mmu_entry ringhd;
+	int num_entries;
+};
+static struct sun4c_mmu_ring sun4c_context_ring[16]; /* used user entries */
+static struct sun4c_mmu_ring sun4c_ufree_ring;       /* free user entries */
+
+static inline void sun4c_next_kernel_bucket(struct sun4c_segment_info **next)
+{
+	(*next)++;
+	*next = (struct sun4c_segment_info *)
+			((unsigned long)*next & ~SUN4C_KERNEL_BSIZE);
+}
+
+static inline void sun4c_init_rings(unsigned long *mempool)
+{
+	int i;
+	for(i=0; i<16; i++) {
+		sun4c_context_ring[i].ringhd.next =
+			sun4c_context_ring[i].ringhd.prev =
+			&sun4c_context_ring[i].ringhd;
+		sun4c_context_ring[i].num_entries = 0;
+	}
+	sun4c_ufree_ring.ringhd.next = sun4c_ufree_ring.ringhd.prev =
+		&sun4c_ufree_ring.ringhd;
+	sun4c_ufree_ring.num_entries = 0;
+	/* This needs to be aligned to twice it's size for speed. */
+	sun4c_kernel_next = sparc_init_alloc(mempool, 2 * SUN4C_KERNEL_BSIZE);
+}
+
+static inline void add_ring(struct sun4c_mmu_ring *ring, struct sun4c_mmu_entry *entry)
+{
+	struct sun4c_mmu_entry *head = &ring->ringhd;
+
+	entry->prev = head;
+	(entry->next = head->next)->prev = entry;
+	head->next = entry;
+	ring->num_entries++;
+}
+
+static inline void remove_ring(struct sun4c_mmu_ring *ring, struct sun4c_mmu_entry *entry)
+{
+	struct sun4c_mmu_entry *next = entry->next;
+
+	(next->prev = entry->prev)->next = next;
+	ring->num_entries--;
+}
+
+static inline void recycle_ring(struct sun4c_mmu_ring *ring, struct sun4c_mmu_entry *entry)
+{
+	struct sun4c_mmu_entry *head = &ring->ringhd;
+	struct sun4c_mmu_entry *next = entry->next;
+
+	(next->prev = entry->prev)->next = next;
+	entry->prev = head; (entry->next = head->next)->prev = entry;
+	head->next = entry;
+	/* num_entries stays the same */
+}
+
+static inline void free_user_entry(int ctx, struct sun4c_mmu_entry *entry)
+{
+        remove_ring(sun4c_context_ring+ctx, entry);
+        add_ring(&sun4c_ufree_ring, entry);
+}
+
+static inline void assign_user_entry(int ctx, struct sun4c_mmu_entry *entry) 
+{
+        remove_ring(&sun4c_ufree_ring, entry);
+        add_ring(sun4c_context_ring+ctx, entry);
+}
+
+static void sun4c_init_fill_kernel_ring(int howmany)
+{
+	int i;
+
+	while(howmany) {
+		for(i=0; i < invalid_segment; i++)
+			if(!mmu_entry_pool[i].locked)
+				break;
+		mmu_entry_pool[i].locked = 1;
+		sun4c_init_clean_segmap(i);
+		sun4c_kernel_next->vaddr = 0;
+		sun4c_kernel_next->pseg = mmu_entry_pool[i].pseg;
+		sun4c_next_kernel_bucket(&sun4c_kernel_next);
+		howmany--;
+	}
+}
+
+static void sun4c_init_fill_user_ring(void)
+{
+	int i;
+
+	for(i=0; i < invalid_segment; i++) {
+		if(mmu_entry_pool[i].locked)
+			continue;
+		sun4c_init_clean_segmap(i);
+		add_ring(&sun4c_ufree_ring, &mmu_entry_pool[i]);
+	}
+}
+
+static inline void sun4c_kernel_unmap(struct sun4c_mmu_entry *kentry)
+{
+	int savectx, ctx;
+
+	savectx = sun4c_get_context();
+	for(ctx = 0; ctx < num_contexts; ctx++) {
+		sun4c_set_context(ctx);
+		sun4c_put_segmap(kentry->vaddr, invalid_segment);
+	}
+	sun4c_set_context(savectx);
+}
+
+static inline void sun4c_kernel_map(struct sun4c_mmu_entry *kentry)
+{
+	int savectx, ctx;
+
+	savectx = sun4c_get_context();
+	for(ctx = 0; ctx < num_contexts; ctx++) {
+		sun4c_set_context(ctx);
+		sun4c_put_segmap(kentry->vaddr, kentry->pseg);
+	}
+	sun4c_set_context(savectx);
+}
+
+static inline void sun4c_user_unmap(struct sun4c_mmu_entry *uentry)
+{
+	/* PM: need flush_user_windows() ?? */
+	sun4c_put_segmap(uentry->vaddr, invalid_segment);
+}
+
+static inline void sun4c_user_map(struct sun4c_mmu_entry *uentry)
+{
+	unsigned long start = uentry->vaddr;
+	unsigned long end = start + SUN4C_REAL_PGDIR_SIZE;
+
+	sun4c_put_segmap(uentry->vaddr, uentry->pseg);
+	while(start < end) {
+		sun4c_put_pte(start, 0);
+		start += PAGE_SIZE;
+	}
+}
+
+static inline void sun4c_demap_context(struct sun4c_mmu_ring *crp, unsigned char ctx)
+{
+	struct sun4c_mmu_entry *this_entry, *next_entry;
+	int savectx = sun4c_get_context();
+
+	this_entry = crp->ringhd.next;
+	flush_user_windows();
+	sun4c_set_context(ctx);
+	sun4c_flush_context();
+	while(crp->num_entries) {
+		next_entry = this_entry->next;
+		sun4c_user_unmap(this_entry);
+		free_user_entry(ctx, this_entry);
+		this_entry = next_entry;
+	}
+	sun4c_set_context(savectx);
+}
+
+static inline void sun4c_demap_one(struct sun4c_mmu_ring *crp,unsigned char ctx)
+{
+	/* by using .prev we get a kind of "lru" algorithm */
+	struct sun4c_mmu_entry *entry = crp->ringhd.prev;
+	int savectx = sun4c_get_context();
+
+	flush_user_windows();
+	sun4c_set_context(ctx);
+	sun4c_flush_segment(entry->vaddr);
+	sun4c_user_unmap(entry);
+	free_user_entry(ctx, entry);
+	sun4c_set_context(savectx);
+}
+
+/* Using this method to free up mmu entries eliminates a lot of
+ * potential races since we have a kernel that incurs tlb
+ * replacement faults.  There may be performance penalties.
+ */
+static inline struct sun4c_mmu_entry *sun4c_user_strategy(void)
+{
+	struct ctx_list *next_one;
+	struct sun4c_mmu_ring *rp = 0;
+	unsigned char ctx;
+
+	/* If some are free, return first one. */
+	if(sun4c_ufree_ring.num_entries)
+		return sun4c_ufree_ring.ringhd.next;
+
+	/* Grab one from the LRU context. */
+	next_one = ctx_used.next;
+	while (sun4c_context_ring[next_one->ctx_number].num_entries == 0)
+		next_one = next_one->next;
+
+	ctx = next_one->ctx_number;
+	rp = &sun4c_context_ring[ctx];
+
+	sun4c_demap_one(rp,ctx);
+	return sun4c_ufree_ring.ringhd.next;
+}
+
+static inline void alloc_user_segment(unsigned long address, unsigned char ctx)
+{
+	struct sun4c_mmu_entry *entry;
+
+	address &= SUN4C_REAL_PGDIR_MASK;
+	entry = sun4c_user_strategy();
+	assign_user_entry(ctx, entry);
+	entry->vaddr = address;
+	sun4c_user_map(entry);
+}
+
+/* XXX Just like kernel tlb replacement we'd like to have a low level
+ * XXX equivalent for user faults which need not go through the mm
+ * XXX subsystem just to load a mmu entry.  But this might not be as
+ * XXX feasible since we need to go through the kernel page tables
+ * XXX for this process, which we currently don't lock into the mmu
+ * XXX so we would fault with traps off... must think about this...
+ */
+void sun4c_update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t pte)
+{
+	unsigned long flags;
+#if 0
+	struct inode *inode;
+	struct vm_area_struct *vmaring;
+	unsigned long offset, vaddr;
+	unsigned long start;
+	pgd_t *pgdp;
+	pmd_t *pmdp;
+	pte_t *ptep;
+#endif
+
+	save_and_cli(flags);
+	address &= PAGE_MASK;
+	if(sun4c_get_segmap(address) == invalid_segment)
+		alloc_user_segment(address, sun4c_get_context());
+	sun4c_put_pte(address, pte_val(pte));
+
+#if 0
+	if (!(vma->vm_flags & VM_WRITE) ||
+	    !(vma->vm_flags & VM_SHARED))
+		goto done;
+
+	inode = vma->vm_inode;
+	if (!inode)
+		goto done;
+
+	offset = (address & PAGE_MASK) - vma->vm_start;
+	vmaring = inode->i_mmap; 
+	do {
+		vaddr = vmaring->vm_start + offset;
+
+		if (S4CVAC_BADALIAS(vaddr, address)) {
+			start = vma->vm_start;
+			while (start < vma->vm_end) {
+				pgdp = pgd_offset(vma->vm_mm, start);
+				pmdp = pmd_offset(pgdp, start);
+				ptep = pte_offset(pmdp, start);
+
+				if (sun4c_get_pte(start) & _SUN4C_PAGE_VALID)
+				sun4c_put_pte(start, sun4c_get_pte(start) |
+						     _SUN4C_PAGE_NOCACHE);
+
+				start += PAGE_SIZE;
+			}
+			goto done;
+		}
+	} while ((vmaring = vmaring->vm_next_share) != inode->i_mmap);
+
+done:
+#endif
+	restore_flags(flags);
+}
+
+/* This is now a fast in-window trap handler to avoid any and all races. */
+static void sun4c_quick_kernel_fault(unsigned long address)
+{
+        printk("Kernel faults at addr=0x%08lx\n", address);
+        panic("sun4c fault handler bolixed...");
+}
+
+/*
+ * 4 page buckets for task struct and kernel stack allocation.
+ *
+ * TASK_STACK_BEGIN
+ * bucket[0]
+ * bucket[1]
+ *   [ ... ]
+ * bucket[NR_TASKS-1]
+ * TASK_STACK_BEGIN + (sizeof(struct task_bucket) * NR_TASKS)
+ *
+ * Each slot looks like:
+ *
+ *  page 1   --  task struct
+ *  page 2   --  unmapped, for stack redzone (maybe use for pgd)
+ *  page 3/4 --  kernel stack
+ */
+
+struct task_bucket {
+	struct task_struct task;
+	char _unused1[PAGE_SIZE - sizeof(struct task_struct)];
+	char kstack[(PAGE_SIZE*3)];
+};
+
+struct task_bucket *sun4c_bucket[NR_TASKS];
+
+#define BUCKET_EMPTY     ((struct task_bucket *) 0)
+#define BUCKET_SIZE      (PAGE_SIZE << 2)
+#define BUCKET_SHIFT     14        /* log2(sizeof(struct task_bucket)) */
+#define BUCKET_NUM(addr) ((((addr) - SUN4C_LOCK_VADDR) >> BUCKET_SHIFT))
+#define BUCKET_ADDR(num) (((num) << BUCKET_SHIFT) + SUN4C_LOCK_VADDR)
+#define BUCKET_PTE(page)       \
+        ((((page) - PAGE_OFFSET) >> PAGE_SHIFT) | pgprot_val(SUN4C_PAGE_KERNEL))
+#define BUCKET_PTE_PAGE(pte)   \
+        (PAGE_OFFSET + (((pte) & 0xffff) << PAGE_SHIFT))
+
+static inline void get_locked_segment(unsigned long addr)
+{
+	struct sun4c_mmu_entry *stolen;
+	unsigned long flags;
+
+	save_and_cli(flags);
+	addr &= SUN4C_REAL_PGDIR_MASK;
+	stolen = sun4c_user_strategy();
+	remove_ring(&sun4c_ufree_ring, stolen);
+	stolen->vaddr = addr;
+	flush_user_windows();
+	sun4c_kernel_map(stolen);
+	restore_flags(flags);
+}
+
+static inline void free_locked_segment(unsigned long addr)
+{
+	struct sun4c_mmu_entry *entry;
+	unsigned long flags;
+	unsigned char pseg;
+
+	save_and_cli(flags);
+	addr &= SUN4C_REAL_PGDIR_MASK;
+	pseg = sun4c_get_segmap(addr);
+	entry = &mmu_entry_pool[pseg];
+	flush_user_windows();
+	sun4c_flush_segment(addr);
+	sun4c_kernel_unmap(entry);
+	add_ring(&sun4c_ufree_ring, entry);
+	restore_flags(flags);
+}
+
+static inline void garbage_collect(int entry)
+{
+	int start, end;
+
+	/* 16 buckets per segment... */
+	entry &= ~15;
+	start = entry;
+	for(end = (start + 16); start < end; start++)
+		if(sun4c_bucket[start] != BUCKET_EMPTY)
+			return;
+	/* Entire segment empty, release it. */
+	free_locked_segment(BUCKET_ADDR(entry));
+}
+
+static struct task_struct *sun4c_alloc_task_struct(void)
+{
+	unsigned long addr, page;
+	int entry;
+
+	page = get_free_page(GFP_KERNEL);
+	if(!page)
+		return (struct task_struct *) 0;
+	/* XXX Bahh, linear search too slow, use hash
+	 * XXX table in final implementation.  Or
+	 * XXX keep track of first free when we free
+	 * XXX a bucket... anything but this.
+	 */
+	for(entry = 0; entry < NR_TASKS; entry++)
+		if(sun4c_bucket[entry] == BUCKET_EMPTY)
+			break;
+	if(entry == NR_TASKS) {
+		free_page(page);
+		return (struct task_struct *) 0;
+	}
+	addr = BUCKET_ADDR(entry);
+	sun4c_bucket[entry] = (struct task_bucket *) addr;
+	if(sun4c_get_segmap(addr) == invalid_segment)
+		get_locked_segment(addr);
+	sun4c_put_pte(addr, BUCKET_PTE(page));
+	return (struct task_struct *) addr;
+}
+
+static unsigned long sun4c_alloc_kernel_stack(struct task_struct *tsk)
+{
+	unsigned long saddr = (unsigned long) tsk;
+	unsigned long page[2];
+
+	if(!saddr)
+		return 0;
+	page[0] = __get_free_page(GFP_KERNEL);
+	if(!page[0])
+		return 0;
+	page[1] = __get_free_page(GFP_KERNEL);
+	if(!page[1]) {
+		free_page(page[0]);
+		return 0;
+	}
+	saddr += (PAGE_SIZE << 1);
+	sun4c_put_pte(saddr, BUCKET_PTE(page[0]));
+	sun4c_put_pte(saddr + PAGE_SIZE, BUCKET_PTE(page[1]));
+	return saddr;
+}
+
+static void sun4c_free_kernel_stack(unsigned long stack)
+{
+	unsigned long page[2];
+
+	page[0] = BUCKET_PTE_PAGE(sun4c_get_pte(stack));
+	page[1] = BUCKET_PTE_PAGE(sun4c_get_pte(stack+PAGE_SIZE));
+	sun4c_flush_page(stack);
+	sun4c_flush_page(stack + PAGE_SIZE);
+	sun4c_put_pte(stack, 0);
+	sun4c_put_pte(stack + PAGE_SIZE, 0);
+	free_page(page[0]);
+	free_page(page[1]);
+}
+
+static void sun4c_free_task_struct(struct task_struct *tsk)
+{
+	unsigned long tsaddr = (unsigned long) tsk;
+	unsigned long page = BUCKET_PTE_PAGE(sun4c_get_pte(tsaddr));
+	int entry = BUCKET_NUM(tsaddr);
+
+	sun4c_flush_page(tsaddr);
+	sun4c_put_pte(tsaddr, 0);
+	sun4c_bucket[entry] = BUCKET_EMPTY;
+	free_page(page);
+	garbage_collect(entry);
+}
+
+static void sun4c_init_buckets(void)
+{
+	int entry;
+
+	if(sizeof(struct task_bucket) != (PAGE_SIZE << 2)) {
+		prom_printf("task bucket not 4 pages!\n");
+		prom_halt();
+	}
+	for(entry = 0; entry < NR_TASKS; entry++)
+		sun4c_bucket[entry] = BUCKET_EMPTY;
+}
+
+static unsigned long sun4c_iobuffer_start;
+static unsigned long sun4c_iobuffer_end;
+static unsigned long sun4c_iobuffer_high;
+static unsigned long *sun4c_iobuffer_map;
+static int iobuffer_map_size;
+
+/*
+ * Alias our pages so they do not cause a trap.
+ * Also one page may be aliased into several I/O areas and we may
+ * finish these I/O separately.
+ */
+static char *sun4c_lockarea(char *vaddr, unsigned long size)
+{
+	unsigned long base, scan;
+	unsigned long npages;
+	unsigned long vpage;
+	unsigned long pte;
+	unsigned long apage;
+	unsigned long high;
+	unsigned long flags;
+
+	npages = (((unsigned long)vaddr & ~PAGE_MASK) +
+		  size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
+
+	scan = 0;
+	save_and_cli(flags);
+	for (;;) {
+		scan = find_next_zero_bit(sun4c_iobuffer_map,
+					  iobuffer_map_size, scan);
+		if ((base = scan) + npages > iobuffer_map_size) goto abend;
+		for (;;) {
+			if (scan >= base + npages) goto found;
+			if (test_bit(scan, sun4c_iobuffer_map)) break;
+			scan++;
+		}
+	}
+
+found:
+	high = ((base + npages) << PAGE_SHIFT) + sun4c_iobuffer_start;
+	high = SUN4C_REAL_PGDIR_ALIGN(high);
+	while (high > sun4c_iobuffer_high) {
+		get_locked_segment(sun4c_iobuffer_high);
+		sun4c_iobuffer_high += SUN4C_REAL_PGDIR_SIZE;
+	}
+
+	vpage = ((unsigned long) vaddr) & PAGE_MASK;
+	for (scan = base; scan < base+npages; scan++) {
+		pte = ((vpage-PAGE_OFFSET) >> PAGE_SHIFT);
+ 		pte |= pgprot_val(SUN4C_PAGE_KERNEL);
+		pte |= _SUN4C_PAGE_NOCACHE;
+		set_bit(scan, sun4c_iobuffer_map);
+		apage = (scan << PAGE_SHIFT) + sun4c_iobuffer_start;
+		sun4c_flush_page(vpage);
+		sun4c_put_pte(apage, pte);
+		vpage += PAGE_SIZE;
+	}
+	restore_flags(flags);
+	return (char *) ((base << PAGE_SHIFT) + sun4c_iobuffer_start +
+			 (((unsigned long) vaddr) & ~PAGE_MASK));
+
+abend:
+	restore_flags(flags);
+	printk("DMA vaddr=0x%p size=%08lx\n", vaddr, size);
+	panic("Out of iobuffer table");
+	return 0;
+}
+
+static void sun4c_unlockarea(char *vaddr, unsigned long size)
+{
+	unsigned long vpage, npages;
+	unsigned long flags;
+	int scan, high;
+
+	vpage = (unsigned long)vaddr & PAGE_MASK;
+	npages = (((unsigned long)vaddr & ~PAGE_MASK) +
+		  size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
+	while (npages != 0) {
+		--npages;
+		sun4c_put_pte(vpage, 0);
+		clear_bit((vpage - sun4c_iobuffer_start) >> PAGE_SHIFT,
+			  sun4c_iobuffer_map);
+		vpage += PAGE_SIZE;
+	}
+
+	/* garbage collect */
+	save_and_cli(flags);
+	scan = (sun4c_iobuffer_high - sun4c_iobuffer_start) >> PAGE_SHIFT;
+	while (scan >= 0 && !sun4c_iobuffer_map[scan >> 5])
+		scan -= 32;
+	scan += 32;
+	high = sun4c_iobuffer_start + (scan << PAGE_SHIFT);
+	high = SUN4C_REAL_PGDIR_ALIGN(high) + SUN4C_REAL_PGDIR_SIZE;
+	while (high < sun4c_iobuffer_high) {
+		sun4c_iobuffer_high -= SUN4C_REAL_PGDIR_SIZE;
+		free_locked_segment(sun4c_iobuffer_high);
+	}
+	restore_flags(flags);
+}
+
+/* Note the scsi code at init time passes to here buffers
+ * which sit on the kernel stack, those are already locked
+ * by implication and fool the page locking code above
+ * if passed to by mistake.
+ */
+static char *sun4c_get_scsi_one(char *bufptr, unsigned long len, struct linux_sbus *sbus)
+{
+	unsigned long page;
+
+	page = ((unsigned long) bufptr) & PAGE_MASK;
+	if(MAP_NR(page) > max_mapnr)
+		return bufptr; /* already locked */
+	return sun4c_lockarea(bufptr, len);
+}
+
+static void sun4c_get_scsi_sgl(struct mmu_sglist *sg, int sz, struct linux_sbus *sbus)
+{
+	while(sz >= 0) {
+		sg[sz].dvma_addr = sun4c_lockarea(sg[sz].addr, sg[sz].len);
+		sz--;
+	}
+}
+
+static void sun4c_release_scsi_one(char *bufptr, unsigned long len, struct linux_sbus *sbus)
+{
+	unsigned long page = (unsigned long) bufptr;
+
+	if(page < sun4c_iobuffer_start)
+		return; /* On kernel stack or similar, see above */
+	sun4c_unlockarea(bufptr, len);
+}
+
+static void sun4c_release_scsi_sgl(struct mmu_sglist *sg, int sz, struct linux_sbus *sbus)
+{
+	while(sz >= 0) {
+		sun4c_unlockarea(sg[sz].dvma_addr, sg[sz].len);
+		sz--;
+	}
+}
+
+#define TASK_ENTRY_SIZE    BUCKET_SIZE /* see above */
+#define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1))
+
+struct vm_area_struct sun4c_kstack_vma;
+
+static unsigned long sun4c_init_lock_areas(unsigned long start_mem)
+{
+	unsigned long sun4c_taskstack_start;
+	unsigned long sun4c_taskstack_end;
+	int bitmap_size;
+
+	sun4c_init_buckets();
+	sun4c_taskstack_start = SUN4C_LOCK_VADDR;
+	sun4c_taskstack_end = (sun4c_taskstack_start +
+			       (TASK_ENTRY_SIZE * NR_TASKS));
+	if(sun4c_taskstack_end >= SUN4C_LOCK_END) {
+		prom_printf("Too many tasks, decrease NR_TASKS please.\n");
+		prom_halt();
+	}
+
+	sun4c_iobuffer_start = sun4c_iobuffer_high =
+				SUN4C_REAL_PGDIR_ALIGN(sun4c_taskstack_end);
+	sun4c_iobuffer_end = SUN4C_LOCK_END;
+	bitmap_size = (sun4c_iobuffer_end - sun4c_iobuffer_start) >> PAGE_SHIFT;
+	bitmap_size = (bitmap_size + 7) >> 3;
+	bitmap_size = LONG_ALIGN(bitmap_size);
+	iobuffer_map_size = bitmap_size << 3;
+	sun4c_iobuffer_map = (unsigned long *) start_mem;
+	memset((void *) start_mem, 0, bitmap_size);
+	start_mem += bitmap_size;
+
+	/* Now get us some mmu entries for I/O maps. */
+	/* sun4c_init_lock_area(sun4c_iobuffer_start, sun4c_iobuffer_end); */
+	sun4c_kstack_vma.vm_mm = init_task.mm;
+	sun4c_kstack_vma.vm_start = sun4c_taskstack_start;
+	sun4c_kstack_vma.vm_end = sun4c_taskstack_end;
+	sun4c_kstack_vma.vm_page_prot = PAGE_SHARED;
+	sun4c_kstack_vma.vm_flags = VM_READ | VM_WRITE | VM_EXEC;
+	insert_vm_struct(&init_mm, &sun4c_kstack_vma);
+	return start_mem;
+}
+
+/* Cache flushing on the sun4c. */
+static void sun4c_flush_cache_all(void)
+{
+	/* Clear all tags in the sun4c cache.
+	 * The cache is write through so this is safe.
+	 */
+	flush_user_windows();
+	__asm__ __volatile__("add	%2, %2, %%g1\n\t"
+			     "add	%2, %%g1, %%g2\n\t"
+			     "add	%2, %%g2, %%g3\n\t"
+			     "add	%2, %%g3, %%g4\n\t"
+			     "add	%2, %%g4, %%g5\n\t"
+			     "add	%2, %%g5, %%o4\n\t"
+			     "add	%2, %%o4, %%o5\n"
+			     "1:\n\t"
+			     "subcc	%1, %%o5, %1\n\t"
+			     "sta	%%g0, [%0] %3\n\t"
+			     "sta	%%g0, [%0 + %2] %3\n\t"
+			     "sta	%%g0, [%0 + %%g1] %3\n\t"
+			     "sta	%%g0, [%0 + %%g2] %3\n\t"
+			     "sta	%%g0, [%0 + %%g3] %3\n\t"
+			     "sta	%%g0, [%0 + %%g4] %3\n\t"
+			     "sta	%%g0, [%0 + %%g5] %3\n\t"
+			     "sta	%%g0, [%0 + %%o4] %3\n\t"
+			     "bg	1b\n\t"
+			     " add	%0, %%o5, %0\n\t" : :
+			     "r" (AC_CACHETAGS),
+			     "r" (sun4c_vacinfo.num_bytes),
+			     "r" (sun4c_vacinfo.linesize),
+			     "i" (ASI_CONTROL) :
+			     "g1", "g2", "g3", "g4", "g5", "o4", "o5");
+}
+
+static void sun4c_flush_cache_mm(struct mm_struct *mm)
+{
+	int octx;
+
+#ifndef __SMP__
+	if(mm->context != NO_CONTEXT) {
+#endif
+		octx = sun4c_get_context();
+		flush_user_windows();
+		sun4c_set_context(mm->context);
+		sun4c_flush_context();
+		sun4c_set_context(octx);
+#ifndef __SMP__
+	}
+#endif
+}
+
+
+static void sun4c_flush_cache_range(struct mm_struct *mm, unsigned long start, unsigned long end)
+{
+	int size, size2, octx, i;
+	unsigned long start2,end2;
+	struct sun4c_mmu_entry *entry,*entry2;
+	
+	/* don't flush kernel memory as its always valid in
+	   all contexts */
+	if (start >= PAGE_OFFSET)
+		return;
+
+#if KGPROF_PROFILING
+	kgprof_profile();
+#endif
+
+#ifndef __SMP__
+	if(mm->context != NO_CONTEXT) {
+#endif
+		size = end - start;
+
+		octx = sun4c_get_context();
+		flush_user_windows();
+		sun4c_set_context(mm->context);
+
+		entry = sun4c_context_ring[mm->context].ringhd.next;
+		i = sun4c_context_ring[mm->context].num_entries;
+		while (i--) {
+			entry2 = entry->next;
+			if (entry->vaddr < start || entry->vaddr >= end) 
+				goto next_entry;
+
+			start2 = MAX(start,entry->vaddr);
+			end2 = MIN(end,entry->vaddr+SUN4C_REAL_PGDIR_SIZE);
+			size2 = end2 - start2;
+
+			if (size2 <= (PAGE_SIZE << 3)) {
+				start2 &= PAGE_MASK;
+				while(start2 < end2) {
+					sun4c_flush_page(start2);
+					start2 += PAGE_SIZE;
+				}
+			} else {
+				start2 &= SUN4C_REAL_PGDIR_MASK;
+				sun4c_flush_segment(start2);
+				/* we are betting that the entry will not be 
+				   needed for a while */
+				sun4c_user_unmap(entry);
+				free_user_entry(mm->context, entry);
+			}
+
+		next_entry:
+			entry = entry2;
+		}
+		sun4c_set_context(octx);
+#ifndef __SMP__
+	}
+#endif
+}
+
+static void sun4c_flush_cache_page(struct vm_area_struct *vma, unsigned long page)
+{
+	int octx;
+	struct mm_struct *mm = vma->vm_mm;
+
+	/* don't flush kernel memory as its always valid in
+	   all contexts */
+	if (page >= PAGE_OFFSET)
+		return;
+
+	/* Sun4c has no separate I/D caches so cannot optimize for non
+	 * text page flushes.
+	 */
+#ifndef __SMP__
+	if(mm->context != NO_CONTEXT) {
+#endif
+		octx = sun4c_get_context();
+		flush_user_windows();
+		sun4c_set_context(mm->context);
+		sun4c_flush_page(page);
+		sun4c_set_context(octx);
+#ifndef __SMP__
+	}
+#endif
+}
+
+/* Sun4c cache is write-through, so no need to validate main memory
+ * during a page copy in kernel space.
+ */
+static void sun4c_flush_page_to_ram(unsigned long page)
+{
+}
+
+/* TLB flushing on the sun4c.  These routines count on the cache
+ * flushing code to flush the user register windows so that we need
+ * not do so when we get here.
+ */
+
+static void sun4c_flush_tlb_all(void)
+{
+	unsigned long flags;
+	int savectx, ctx, entry;
+
+	save_and_cli(flags);
+	savectx = sun4c_get_context();
+	for (entry = 0; entry < SUN4C_KERNEL_BUCKETS; entry++) {
+		if (sun4c_kernel_next->vaddr) {
+			for(ctx = 0; ctx < num_contexts; ctx++) {
+				sun4c_set_context(ctx);
+				sun4c_put_segmap(sun4c_kernel_next->vaddr,
+						 invalid_segment);
+			}
+			sun4c_kernel_next->vaddr = 0;
+		}
+		sun4c_next_kernel_bucket(&sun4c_kernel_next);
+	}
+	sun4c_set_context(savectx);
+	restore_flags(flags);
+}
+
+static void sun4c_flush_tlb_mm(struct mm_struct *mm)
+{
+	struct sun4c_mmu_entry *this_entry, *next_entry;
+	struct sun4c_mmu_ring *crp;
+	int savectx, ctx;
+
+#ifndef __SMP__
+	if(mm->context != NO_CONTEXT) {
+#endif
+		crp = &sun4c_context_ring[mm->context];
+		savectx = sun4c_get_context();
+		ctx = mm->context;
+		this_entry = crp->ringhd.next;
+		flush_user_windows();
+		sun4c_set_context(mm->context);
+		sun4c_flush_context();
+		while(crp->num_entries) {
+			next_entry = this_entry->next;
+			sun4c_user_unmap(this_entry);
+			free_user_entry(ctx, this_entry);
+			this_entry = next_entry;
+		}
+		sun4c_set_context(savectx);
+#ifndef __SMP__
+	}
+#endif
+}
+
+static void sun4c_flush_tlb_range(struct mm_struct *mm, unsigned long start, unsigned long end)
+{
+	struct sun4c_mmu_entry *entry,*entry2;
+	unsigned char savectx;
+	int i;
+
+#ifndef __SMP__
+	if(mm->context == NO_CONTEXT)
+		return;
+#endif
+
+#if KGPROF_PROFILING
+	kgprof_profile();
+#endif
+
+	savectx = sun4c_get_context();
+	sun4c_set_context(mm->context);
+	start &= SUN4C_REAL_PGDIR_MASK;
+
+	entry = sun4c_context_ring[mm->context].ringhd.next;
+	i = sun4c_context_ring[mm->context].num_entries;
+	while (i--) {
+		entry2 = entry->next;
+		if (entry->vaddr >= start && entry->vaddr < end) {
+			sun4c_flush_segment(entry->vaddr);
+			sun4c_user_unmap(entry);
+			free_user_entry(mm->context, entry);
+		}
+		entry = entry2;
+	}
+	sun4c_set_context(savectx);
+}
+
+
+static void sun4c_flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
+{
+	struct mm_struct *mm = vma->vm_mm;
+	int savectx;
+
+#ifndef __SMP__
+	if(mm->context != NO_CONTEXT) {
+#endif
+		savectx = sun4c_get_context();
+		sun4c_set_context(mm->context);
+		page &= PAGE_MASK;
+		if(sun4c_get_pte(page) & _SUN4C_PAGE_VALID)
+			sun4c_put_pte(page, 0);
+		sun4c_set_context(savectx);
+#ifndef __SMP__
+	}
+#endif
+}
+
+/* Sun4c mmu hardware doesn't update the dirty bit in the pte's
+ * for us, so we do it in software.
+ */
+static void sun4c_set_pte(pte_t *ptep, pte_t pte)
+{
+
+	if((pte_val(pte) & (_SUN4C_PAGE_WRITE|_SUN4C_PAGE_DIRTY)) ==
+	   _SUN4C_PAGE_WRITE)
+		pte_val(pte) |= _SUN4C_PAGE_DIRTY;
+
+	*ptep = pte;
+}
+
+void sun4c_mapioaddr(unsigned long physaddr, unsigned long virt_addr,
+		     int bus_type, int rdonly)
+{
+	unsigned long page_entry;
+
+	page_entry = ((physaddr >> PAGE_SHIFT) & 0xffff);
+	page_entry |= (_SUN4C_PAGE_VALID | _SUN4C_PAGE_WRITE |
+		       _SUN4C_PAGE_NOCACHE | _SUN4C_PAGE_IO);
+	if(rdonly)
+		page_entry &= (~_SUN4C_PAGE_WRITE);
+	sun4c_flush_page(virt_addr);
+	sun4c_put_pte(virt_addr, page_entry);
+}
+
+void sun4c_unmapioaddr(unsigned long virt_addr)
+{
+	sun4c_flush_page(virt_addr); /* XXX P3: Is it necessary for I/O page? */
+	sun4c_put_pte(virt_addr, 0);
+}
+
+static inline void sun4c_alloc_context(struct mm_struct *mm)
+{
+	struct ctx_list *ctxp;
+
+	ctxp = ctx_free.next;
+	if(ctxp != &ctx_free) {
+		remove_from_ctx_list(ctxp);
+		add_to_used_ctxlist(ctxp);
+		mm->context = ctxp->ctx_number;
+		ctxp->ctx_mm = mm;
+		return;
+	}
+	ctxp = ctx_used.next;
+	if(ctxp->ctx_mm == current->mm)
+		ctxp = ctxp->next;
+	if(ctxp == &ctx_used)
+		panic("out of mmu contexts");
+	remove_from_ctx_list(ctxp);
+	add_to_used_ctxlist(ctxp);
+	ctxp->ctx_mm->context = NO_CONTEXT;
+	ctxp->ctx_mm = mm;
+	mm->context = ctxp->ctx_number;
+	sun4c_demap_context(&sun4c_context_ring[ctxp->ctx_number],
+			    ctxp->ctx_number);
+}
+
+#if some_day_soon /* We need some tweaking to start using this */
+extern void force_user_fault(unsigned long, int);
+
+void sun4c_switch_heuristic(struct pt_regs *regs)
+{
+	unsigned long sp = regs->u_regs[UREG_FP];
+	unsigned long sp2 = sp + REGWIN_SZ - 0x8;
+
+	force_user_fault(regs->pc, 0);
+	force_user_fault(sp, 0);
+	if((sp&PAGE_MASK) != (sp2&PAGE_MASK))
+		force_user_fault(sp2, 0);
+}
+#endif
+
+static void sun4c_switch_to_context(struct task_struct *tsk)
+{
+	struct ctx_list *ctx;
+
+	if(tsk->mm->context == NO_CONTEXT) {
+		sun4c_alloc_context(tsk->mm);
+		goto set_context;
+	}
+
+	/* Update the LRU ring of contexts. */
+	ctx = ctx_list_pool + tsk->mm->context;
+	remove_from_ctx_list(ctx);
+	add_to_used_ctxlist(ctx);
+
+set_context:
+	sun4c_set_context(tsk->mm->context);
+}
+
+static void sun4c_flush_hook(void)
+{
+	if(current->tss.flags & SPARC_FLAG_KTHREAD) {
+		sun4c_alloc_context(current->mm);
+		sun4c_set_context(current->mm->context);
+	}
+}
+
+static void sun4c_exit_hook(void)
+{
+	struct ctx_list *ctx_old;
+	struct mm_struct *mm = current->mm;
+
+	if(mm->context != NO_CONTEXT && mm->count == 1) {
+		sun4c_demap_context(&sun4c_context_ring[mm->context], mm->context);
+		ctx_old = ctx_list_pool + mm->context;
+		remove_from_ctx_list(ctx_old);
+		add_to_free_ctxlist(ctx_old);
+		mm->context = NO_CONTEXT;
+	}
+}
+
+#if KGPROF_PROFILING
+static char s4cinfo[10240];
+#else
+static char s4cinfo[512];
+#endif
+
+static char *sun4c_mmu_info(void)
+{
+	int used_user_entries, i;
+
+	used_user_entries = 0;
+	for(i=0; i < num_contexts; i++)
+		used_user_entries += sun4c_context_ring[i].num_entries;
+
+	sprintf(s4cinfo, "vacsize\t\t: %d bytes\n"
+		"vachwflush\t: %s\n"
+		"vaclinesize\t: %d bytes\n"
+		"mmuctxs\t\t: %d\n"
+		"mmupsegs\t: %d\n"
+		"kernelpsegs\t: %d\n"
+		"usedpsegs\t: %d\n"
+		"ufreepsegs\t: %d\n"
+		"context\t\t: %d flushes\n"
+		"segment\t\t: %d flushes\n"
+		"page\t\t: %d flushes\n",
+		sun4c_vacinfo.num_bytes,
+		(sun4c_vacinfo.do_hwflushes ? "yes" : "no"),
+		sun4c_vacinfo.linesize,
+		num_contexts,
+		(invalid_segment + 1),
+		invalid_segment - used_user_entries -
+			sun4c_ufree_ring.num_entries + 1,
+		used_user_entries,
+		sun4c_ufree_ring.num_entries,
+		ctxflushes, segflushes, pageflushes);
+
+#if KGPROF_PROFILING
+	{
+		char *p = s4cinfo + strlen(s4cinfo);
+		int i,j;
+		sprintf(p,"kgprof profiling:\n"); p += strlen(p);
+		for (i=0;i<KGPROF_SIZE && kgprof_counters[i].addr[0];i++) {
+			sprintf(p,"%5d  ",kgprof_counters[i].count); p += strlen(p);
+			for (j=0;j<KGPROF_DEPTH;j++) {
+				sprintf(p,"%08x ",kgprof_counters[i].addr[j]);
+				p += strlen(p);
+			}
+			sprintf(p,"\n"); p += strlen(p);
+		}
+	}
+#endif
+
+	return s4cinfo;
+}
+
+/* Nothing below here should touch the mmu hardware nor the mmu_entry
+ * data structures.
+ */
+
+static unsigned int sun4c_pmd_align(unsigned int addr) { return SUN4C_PMD_ALIGN(addr); }
+static unsigned int sun4c_pgdir_align(unsigned int addr) { return SUN4C_PGDIR_ALIGN(addr); }
+
+/* First the functions which the mid-level code uses to directly
+ * manipulate the software page tables.  Some defines since we are
+ * emulating the i386 page directory layout.
+ */
+#define PGD_PRESENT  0x001
+#define PGD_RW       0x002
+#define PGD_USER     0x004
+#define PGD_ACCESSED 0x020
+#define PGD_DIRTY    0x040
+#define PGD_TABLE    (PGD_PRESENT | PGD_RW | PGD_USER | PGD_ACCESSED | PGD_DIRTY)
+
+static unsigned long sun4c_vmalloc_start(void)
+{
+	return SUN4C_VMALLOC_START;
+}
+
+static int sun4c_pte_none(pte_t pte)		{ return !pte_val(pte); }
+static int sun4c_pte_present(pte_t pte)	        { return pte_val(pte) & _SUN4C_PAGE_VALID; }
+static void sun4c_pte_clear(pte_t *ptep)	{ pte_val(*ptep) = 0; }
+
+static int sun4c_pmd_none(pmd_t pmd)		{ return !pmd_val(pmd); }
+static int sun4c_pmd_bad(pmd_t pmd)
+{
+	return (pmd_val(pmd) & ~PAGE_MASK) != PGD_TABLE ||
+		MAP_NR(pmd_val(pmd)) > max_mapnr;
+}
+
+static int sun4c_pmd_present(pmd_t pmd)	        { return pmd_val(pmd) & PGD_PRESENT; }
+static void sun4c_pmd_clear(pmd_t *pmdp)	{ pmd_val(*pmdp) = 0; }
+
+static int sun4c_pgd_none(pgd_t pgd)		{ return 0; }
+static int sun4c_pgd_bad(pgd_t pgd)		{ return 0; }
+static int sun4c_pgd_present(pgd_t pgd)	        { return 1; }
+static void sun4c_pgd_clear(pgd_t * pgdp)	{ }
+
+/*
+ * The following only work if pte_present() is true.
+ * Undefined behaviour if not..
+ */
+static int sun4c_pte_write(pte_t pte)		{ return pte_val(pte) & _SUN4C_PAGE_WRITE; }
+static int sun4c_pte_dirty(pte_t pte)		{ return pte_val(pte) & _SUN4C_PAGE_DIRTY; }
+static int sun4c_pte_young(pte_t pte)		{ return pte_val(pte) & _SUN4C_PAGE_REF; }
+
+static pte_t sun4c_pte_wrprotect(pte_t pte)	{ pte_val(pte) &= ~_SUN4C_PAGE_WRITE; return pte; }
+static pte_t sun4c_pte_mkclean(pte_t pte)	{ pte_val(pte) &= ~_SUN4C_PAGE_DIRTY; return pte; }
+static pte_t sun4c_pte_mkold(pte_t pte)	        { pte_val(pte) &= ~_SUN4C_PAGE_REF; return pte; }
+static pte_t sun4c_pte_mkwrite(pte_t pte)	{ pte_val(pte) |= _SUN4C_PAGE_WRITE; return pte; }
+static pte_t sun4c_pte_mkdirty(pte_t pte)	{ pte_val(pte) |= _SUN4C_PAGE_DIRTY; return pte; }
+static pte_t sun4c_pte_mkyoung(pte_t pte)	{ pte_val(pte) |= _SUN4C_PAGE_REF; return pte; }
+
+/*
+ * Conversion functions: convert a page and protection to a page entry,
+ * and a page entry and page directory to the page they refer to.
+ */
+static pte_t sun4c_mk_pte(unsigned long page, pgprot_t pgprot)
+{
+	return __pte(((page - PAGE_OFFSET) >> PAGE_SHIFT) | pgprot_val(pgprot));
+}
+
+static pte_t sun4c_mk_pte_phys(unsigned long phys_page, pgprot_t pgprot)
+{
+	return __pte((phys_page >> PAGE_SHIFT) | pgprot_val(pgprot));
+}
+
+static pte_t sun4c_mk_pte_io(unsigned long page, pgprot_t pgprot, int space)
+{
+	return __pte(((page - PAGE_OFFSET) >> PAGE_SHIFT) | pgprot_val(pgprot));
+}
+
+static pte_t sun4c_pte_modify(pte_t pte, pgprot_t newprot)
+{
+	return __pte((pte_val(pte) & _SUN4C_PAGE_CHG_MASK) | pgprot_val(newprot));
+}
+
+static unsigned long sun4c_pte_page(pte_t pte)
+{
+	return (PAGE_OFFSET + ((pte_val(pte) & 0xffff) << (PAGE_SHIFT)));
+}
+
+static unsigned long sun4c_pmd_page(pmd_t pmd)
+{
+	return (pmd_val(pmd) & PAGE_MASK);
+}
+
+/* to find an entry in a page-table-directory */
+pgd_t *sun4c_pgd_offset(struct mm_struct * mm, unsigned long address)
+{
+	return mm->pgd + (address >> SUN4C_PGDIR_SHIFT);
+}
+
+/* Find an entry in the second-level page table.. */
+static pmd_t *sun4c_pmd_offset(pgd_t * dir, unsigned long address)
+{
+	return (pmd_t *) dir;
+}
+
+/* Find an entry in the third-level page table.. */ 
+pte_t *sun4c_pte_offset(pmd_t * dir, unsigned long address)
+{
+	return (pte_t *) sun4c_pmd_page(*dir) +	((address >> PAGE_SHIFT) & (SUN4C_PTRS_PER_PTE - 1));
+}
+
+/* Update the root mmu directory. */
+static void sun4c_update_rootmmu_dir(struct task_struct *tsk, pgd_t *pgdir)
+{
+}
+
+/* Allocate and free page tables. The xxx_kernel() versions are
+ * used to allocate a kernel page table - this turns on ASN bits
+ * if any, and marks the page tables reserved.
+ */
+static void sun4c_pte_free_kernel(pte_t *pte)
+{
+	free_page((unsigned long) pte);
+}
+
+static pte_t *sun4c_pte_alloc_kernel(pmd_t *pmd, unsigned long address)
+{
+	address = (address >> PAGE_SHIFT) & (SUN4C_PTRS_PER_PTE - 1);
+	if (sun4c_pmd_none(*pmd)) {
+		pte_t *page = (pte_t *) get_free_page(GFP_KERNEL);
+		if (sun4c_pmd_none(*pmd)) {
+			if (page) {
+				pmd_val(*pmd) = PGD_TABLE | (unsigned long) page;
+				return page + address;
+			}
+			pmd_val(*pmd) = PGD_TABLE | (unsigned long) BAD_PAGETABLE;
+			return NULL;
+		}
+		free_page((unsigned long) page);
+	}
+	if (sun4c_pmd_bad(*pmd)) {
+		printk("Bad pmd in pte_alloc_kernel: %08lx\n", pmd_val(*pmd));
+		pmd_val(*pmd) = PGD_TABLE | (unsigned long) BAD_PAGETABLE;
+		return NULL;
+	}
+	return (pte_t *) sun4c_pmd_page(*pmd) + address;
+}
+
+/*
+ * allocating and freeing a pmd is trivial: the 1-entry pmd is
+ * inside the pgd, so has no extra memory associated with it.
+ */
+static void sun4c_pmd_free_kernel(pmd_t *pmd)
+{
+	pmd_val(*pmd) = 0;
+}
+
+static pmd_t *sun4c_pmd_alloc_kernel(pgd_t *pgd, unsigned long address)
+{
+	return (pmd_t *) pgd;
+}
+
+static void sun4c_pte_free(pte_t *pte)
+{
+	free_page((unsigned long) pte);
+}
+
+static pte_t *sun4c_pte_alloc(pmd_t * pmd, unsigned long address)
+{
+	address = (address >> PAGE_SHIFT) & (SUN4C_PTRS_PER_PTE - 1);
+	if (sun4c_pmd_none(*pmd)) {
+		pte_t *page = (pte_t *) get_free_page(GFP_KERNEL);
+		if (sun4c_pmd_none(*pmd)) {
+			if (page) {
+				pmd_val(*pmd) = PGD_TABLE | (unsigned long) page;
+				return page + address;
+			}
+			pmd_val(*pmd) = PGD_TABLE | (unsigned long) BAD_PAGETABLE;
+			return NULL;
+		}
+		free_page((unsigned long) page);
+	}
+	if (sun4c_pmd_bad(*pmd)) {
+		printk("Bad pmd in pte_alloc: %08lx\n", pmd_val(*pmd));
+		pmd_val(*pmd) = PGD_TABLE | (unsigned long) BAD_PAGETABLE;
+		return NULL;
+	}
+	return (pte_t *) sun4c_pmd_page(*pmd) + address;
+}
+
+/*
+ * allocating and freeing a pmd is trivial: the 1-entry pmd is
+ * inside the pgd, so has no extra memory associated with it.
+ */
+static void sun4c_pmd_free(pmd_t * pmd)
+{
+	pmd_val(*pmd) = 0;
+}
+
+static pmd_t *sun4c_pmd_alloc(pgd_t * pgd, unsigned long address)
+{
+	return (pmd_t *) pgd;
+}
+
+static void sun4c_pgd_free(pgd_t *pgd)
+{
+	free_page((unsigned long) pgd);
+}
+
+static pgd_t *sun4c_pgd_alloc(void)
+{
+	return (pgd_t *) get_free_page(GFP_KERNEL);
+}
+
+extern unsigned long free_area_init(unsigned long, unsigned long);
+extern unsigned long sparc_context_init(unsigned long, int);
+extern unsigned long end;
+
+unsigned long sun4c_paging_init(unsigned long start_mem, unsigned long end_mem)
+{
+	int i, cnt;
+	unsigned long kernel_end;
+	extern unsigned long sparc_iobase_vaddr;
+
+	kernel_end = (unsigned long) &end;
+	kernel_end += (SUN4C_REAL_PGDIR_SIZE * 3);
+	kernel_end = SUN4C_REAL_PGDIR_ALIGN(kernel_end);
+	sun4c_probe_mmu();
+	invalid_segment = (num_segmaps - 1);
+	sun4c_init_mmu_entry_pool();
+	sun4c_init_rings(&start_mem);
+	sun4c_init_map_kernelprom(kernel_end);
+	sun4c_init_clean_mmu(kernel_end);
+	sun4c_init_fill_kernel_ring(SUN4C_KERNEL_BUCKETS);
+	sun4c_init_lock_area(sparc_iobase_vaddr, IOBASE_END);
+	sun4c_init_lock_area(DVMA_VADDR, DVMA_END);
+	start_mem = sun4c_init_lock_areas(start_mem);
+	sun4c_init_fill_user_ring();
+
+	sun4c_set_context(0);
+	memset(swapper_pg_dir, 0, PAGE_SIZE);
+	memset(pg0, 0, PAGE_SIZE);
+	/* Save work later. */
+	pgd_val(swapper_pg_dir[SUN4C_VMALLOC_START>>SUN4C_PGDIR_SHIFT]) =
+		PGD_TABLE | (unsigned long) pg0;
+	sun4c_init_ss2_cache_bug();
+	start_mem = PAGE_ALIGN(start_mem);
+	/* start_mem = sun4c_init_alloc_dvma_pages(start_mem); */
+	start_mem = sparc_context_init(start_mem, num_contexts);
+	start_mem = free_area_init(start_mem, end_mem);
+	cnt = 0;
+	for(i = 0; i < num_segmaps; i++)
+		if(mmu_entry_pool[i].locked)
+			cnt++;
+	printk("SUN4C: %d mmu entries for the kernel\n", cnt);
+	return start_mem;
+}
+
+/* Load up routines and constants for sun4c mmu */
+void ld_mmu_sun4c(void)
+{
+	printk("Loading sun4c MMU routines\n");
+
+	/* First the constants */
+	pmd_shift = SUN4C_PMD_SHIFT;
+	pmd_size = SUN4C_PMD_SIZE;
+	pmd_mask = SUN4C_PMD_MASK;
+	pgdir_shift = SUN4C_PGDIR_SHIFT;
+	pgdir_size = SUN4C_PGDIR_SIZE;
+	pgdir_mask = SUN4C_PGDIR_MASK;
+
+	ptrs_per_pte = SUN4C_PTRS_PER_PTE;
+	ptrs_per_pmd = SUN4C_PTRS_PER_PMD;
+	ptrs_per_pgd = SUN4C_PTRS_PER_PGD;
+
+	page_none = SUN4C_PAGE_NONE;
+	page_shared = SUN4C_PAGE_SHARED;
+	page_copy = SUN4C_PAGE_COPY;
+	page_readonly = SUN4C_PAGE_READONLY;
+	page_kernel = SUN4C_PAGE_KERNEL;
+	pg_iobits = _SUN4C_PAGE_NOCACHE | _SUN4C_PAGE_IO | _SUN4C_PAGE_VALID
+	    | _SUN4C_PAGE_WRITE | _SUN4C_PAGE_DIRTY;
+	
+	/* Functions */
+#ifndef __SMP__
+	flush_cache_all = sun4c_flush_cache_all;
+	flush_cache_mm = sun4c_flush_cache_mm;
+	flush_cache_range = sun4c_flush_cache_range;
+	flush_cache_page = sun4c_flush_cache_page;
+
+	flush_tlb_all = sun4c_flush_tlb_all;
+	flush_tlb_mm = sun4c_flush_tlb_mm;
+	flush_tlb_range = sun4c_flush_tlb_range;
+	flush_tlb_page = sun4c_flush_tlb_page;
+#else
+	local_flush_cache_all = sun4c_flush_cache_all;
+	local_flush_cache_mm = sun4c_flush_cache_mm;
+	local_flush_cache_range = sun4c_flush_cache_range;
+	local_flush_cache_page = sun4c_flush_cache_page;
+
+	local_flush_tlb_all = sun4c_flush_tlb_all;
+	local_flush_tlb_mm = sun4c_flush_tlb_mm;
+	local_flush_tlb_range = sun4c_flush_tlb_range;
+	local_flush_tlb_page = sun4c_flush_tlb_page;
+
+	flush_cache_all = smp_flush_cache_all;
+	flush_cache_mm = smp_flush_cache_mm;
+	flush_cache_range = smp_flush_cache_range;
+	flush_cache_page = smp_flush_cache_page;
+
+	flush_tlb_all = smp_flush_tlb_all;
+	flush_tlb_mm = smp_flush_tlb_mm;
+	flush_tlb_range = smp_flush_tlb_range;
+	flush_tlb_page = smp_flush_tlb_page;
+#endif
+
+	flush_page_to_ram = sun4c_flush_page_to_ram;
+
+	set_pte = sun4c_set_pte;
+	switch_to_context = sun4c_switch_to_context;
+	pmd_align = sun4c_pmd_align;
+	pgdir_align = sun4c_pgdir_align;
+	vmalloc_start = sun4c_vmalloc_start;
+
+	pte_page = sun4c_pte_page;
+	pmd_page = sun4c_pmd_page;
+
+	sparc_update_rootmmu_dir = sun4c_update_rootmmu_dir;
+
+	pte_none = sun4c_pte_none;
+	pte_present = sun4c_pte_present;
+	pte_clear = sun4c_pte_clear;
+
+	pmd_none = sun4c_pmd_none;
+	pmd_bad = sun4c_pmd_bad;
+	pmd_present = sun4c_pmd_present;
+	pmd_clear = sun4c_pmd_clear;
+
+	pgd_none = sun4c_pgd_none;
+	pgd_bad = sun4c_pgd_bad;
+	pgd_present = sun4c_pgd_present;
+	pgd_clear = sun4c_pgd_clear;
+
+	mk_pte = sun4c_mk_pte;
+	mk_pte_phys = sun4c_mk_pte_phys;
+	mk_pte_io = sun4c_mk_pte_io;
+	pte_modify = sun4c_pte_modify;
+	pgd_offset = sun4c_pgd_offset;
+	pmd_offset = sun4c_pmd_offset;
+	pte_offset = sun4c_pte_offset;
+	pte_free_kernel = sun4c_pte_free_kernel;
+	pmd_free_kernel = sun4c_pmd_free_kernel;
+	pte_alloc_kernel = sun4c_pte_alloc_kernel;
+	pmd_alloc_kernel = sun4c_pmd_alloc_kernel;
+	pte_free = sun4c_pte_free;
+	pte_alloc = sun4c_pte_alloc;
+	pmd_free = sun4c_pmd_free;
+	pmd_alloc = sun4c_pmd_alloc;
+	pgd_free = sun4c_pgd_free;
+	pgd_alloc = sun4c_pgd_alloc;
+
+	pte_write = sun4c_pte_write;
+	pte_dirty = sun4c_pte_dirty;
+	pte_young = sun4c_pte_young;
+	pte_wrprotect = sun4c_pte_wrprotect;
+	pte_mkclean = sun4c_pte_mkclean;
+	pte_mkold = sun4c_pte_mkold;
+	pte_mkwrite = sun4c_pte_mkwrite;
+	pte_mkdirty = sun4c_pte_mkdirty;
+	pte_mkyoung = sun4c_pte_mkyoung;
+	update_mmu_cache = sun4c_update_mmu_cache;
+	mmu_exit_hook = sun4c_exit_hook;
+	mmu_flush_hook = sun4c_flush_hook;
+	mmu_lockarea = sun4c_lockarea;
+	mmu_unlockarea = sun4c_unlockarea;
+
+	mmu_get_scsi_one = sun4c_get_scsi_one;
+	mmu_get_scsi_sgl = sun4c_get_scsi_sgl;
+	mmu_release_scsi_one = sun4c_release_scsi_one;
+	mmu_release_scsi_sgl = sun4c_release_scsi_sgl;
+
+	mmu_map_dma_area = sun4c_map_dma_area;
+
+        mmu_v2p = sun4c_v2p;
+        mmu_p2v = sun4c_p2v;
+	
+	/* Task struct and kernel stack allocating/freeing. */
+	alloc_kernel_stack = sun4c_alloc_kernel_stack;
+	alloc_task_struct = sun4c_alloc_task_struct;
+	free_kernel_stack = sun4c_free_kernel_stack;
+	free_task_struct = sun4c_free_task_struct;
+
+	quick_kernel_fault = sun4c_quick_kernel_fault;
+	mmu_info = sun4c_mmu_info;
+
+	/* These should _never_ get called with two level tables. */
+	pgd_set = 0;
+	pgd_page = 0;
+}