Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 601 insertions, 0 deletions

diff --git a/arch/sh64/mm/fault.c b/arch/sh64/mm/fault.c
new file mode 100644
index 00000000000..a24932881db
--- /dev/null
+++ b/arch/sh64/mm/fault.c
@@ -0,0 +1,601 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * arch/sh64/mm/fault.c
+ *
+ * Copyright (C) 2000, 2001  Paolo Alberelli
+ * Copyright (C) 2003  Richard Curnow (/proc/tlb, bug fixes)
+ * Copyright (C) 2003  Paul Mundt
+ *
+ */
+
+#include <linux/signal.h>
+#include <linux/rwsem.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/interrupt.h>
+
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/tlb.h>
+#include <asm/uaccess.h>
+#include <asm/pgalloc.h>
+#include <asm/mmu_context.h>
+#include <asm/registers.h>		/* required by inline asm statements */
+
+#if defined(CONFIG_SH64_PROC_TLB)
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+/* Count numbers of tlb refills in each region */
+static unsigned long long calls_to_update_mmu_cache = 0ULL;
+static unsigned long long calls_to_flush_tlb_page   = 0ULL;
+static unsigned long long calls_to_flush_tlb_range  = 0ULL;
+static unsigned long long calls_to_flush_tlb_mm     = 0ULL;
+static unsigned long long calls_to_flush_tlb_all    = 0ULL;
+unsigned long long calls_to_do_slow_page_fault = 0ULL;
+unsigned long long calls_to_do_fast_page_fault = 0ULL;
+
+/* Count size of ranges for flush_tlb_range */
+static unsigned long long flush_tlb_range_1         = 0ULL;
+static unsigned long long flush_tlb_range_2         = 0ULL;
+static unsigned long long flush_tlb_range_3_4       = 0ULL;
+static unsigned long long flush_tlb_range_5_7       = 0ULL;
+static unsigned long long flush_tlb_range_8_11      = 0ULL;
+static unsigned long long flush_tlb_range_12_15     = 0ULL;
+static unsigned long long flush_tlb_range_16_up     = 0ULL;
+
+static unsigned long long page_not_present          = 0ULL;
+
+#endif
+
+extern void die(const char *,struct pt_regs *,long);
+
+#define PFLAG(val,flag)   (( (val) & (flag) ) ? #flag : "" )
+#define PPROT(flag) PFLAG(pgprot_val(prot),flag)
+
+static inline void print_prots(pgprot_t prot)
+{
+	printk("prot is 0x%08lx\n",pgprot_val(prot));
+
+	printk("%s %s %s %s %s\n",PPROT(_PAGE_SHARED),PPROT(_PAGE_READ),
+	       PPROT(_PAGE_EXECUTE),PPROT(_PAGE_WRITE),PPROT(_PAGE_USER));
+}
+
+static inline void print_vma(struct vm_area_struct *vma)
+{
+	printk("vma start 0x%08lx\n", vma->vm_start);
+	printk("vma end   0x%08lx\n", vma->vm_end);
+
+	print_prots(vma->vm_page_prot);
+	printk("vm_flags 0x%08lx\n", vma->vm_flags);
+}
+
+static inline void print_task(struct task_struct *tsk)
+{
+	printk("Task pid %d\n", tsk->pid);
+}
+
+static pte_t *lookup_pte(struct mm_struct *mm, unsigned long address)
+{
+	pgd_t *dir;
+	pmd_t *pmd;
+	pte_t *pte;
+	pte_t entry;
+
+	dir = pgd_offset(mm, address);
+	if (pgd_none(*dir)) {
+		return NULL;
+	}
+
+	pmd = pmd_offset(dir, address);
+	if (pmd_none(*pmd)) {
+		return NULL;
+	}
+
+	pte = pte_offset_kernel(pmd, address);
+	entry = *pte;
+
+	if (pte_none(entry)) {
+		return NULL;
+	}
+	if (!pte_present(entry)) {
+		return NULL;
+	}
+
+	return pte;
+}
+
+/*
+ * This routine handles page faults.  It determines the address,
+ * and the problem, and then passes it off to one of the appropriate
+ * routines.
+ */
+asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long writeaccess,
+			      unsigned long textaccess, unsigned long address)
+{
+	struct task_struct *tsk;
+	struct mm_struct *mm;
+	struct vm_area_struct * vma;
+	const struct exception_table_entry *fixup;
+	pte_t *pte;
+
+#if defined(CONFIG_SH64_PROC_TLB)
+        ++calls_to_do_slow_page_fault;
+#endif
+
+	/* SIM
+	 * Note this is now called with interrupts still disabled
+	 * This is to cope with being called for a missing IO port
+	 * address with interupts disabled. This should be fixed as
+	 * soon as we have a better 'fast path' miss handler.
+	 *
+	 * Plus take care how you try and debug this stuff.
+	 * For example, writing debug data to a port which you
+	 * have just faulted on is not going to work.
+	 */
+
+	tsk = current;
+	mm = tsk->mm;
+
+	/* Not an IO address, so reenable interrupts */
+	local_irq_enable();
+
+	/*
+	 * If we're in an interrupt or have no user
+	 * context, we must not take the fault..
+	 */
+	if (in_interrupt() || !mm)
+		goto no_context;
+
+	/* TLB misses upon some cache flushes get done under cli() */
+	down_read(&mm->mmap_sem);
+
+	vma = find_vma(mm, address);
+
+	if (!vma) {
+#ifdef DEBUG_FAULT
+		print_task(tsk);
+		printk("%s:%d fault, address is 0x%08x PC %016Lx textaccess %d writeaccess %d\n",
+		       __FUNCTION__,__LINE__,
+		       address,regs->pc,textaccess,writeaccess);
+		show_regs(regs);
+#endif
+		goto bad_area;
+	}
+	if (vma->vm_start <= address) {
+		goto good_area;
+	}
+
+	if (!(vma->vm_flags & VM_GROWSDOWN)) {
+#ifdef DEBUG_FAULT
+		print_task(tsk);
+		printk("%s:%d fault, address is 0x%08x PC %016Lx textaccess %d writeaccess %d\n",
+		       __FUNCTION__,__LINE__,
+		       address,regs->pc,textaccess,writeaccess);
+		show_regs(regs);
+
+		print_vma(vma);
+#endif
+		goto bad_area;
+	}
+	if (expand_stack(vma, address)) {
+#ifdef DEBUG_FAULT
+		print_task(tsk);
+		printk("%s:%d fault, address is 0x%08x PC %016Lx textaccess %d writeaccess %d\n",
+		       __FUNCTION__,__LINE__,
+		       address,regs->pc,textaccess,writeaccess);
+		show_regs(regs);
+#endif
+		goto bad_area;
+	}
+/*
+ * Ok, we have a good vm_area for this memory access, so
+ * we can handle it..
+ */
+good_area:
+	if (textaccess) {
+		if (!(vma->vm_flags & VM_EXEC))
+			goto bad_area;
+	} else {
+		if (writeaccess) {
+			if (!(vma->vm_flags & VM_WRITE))
+				goto bad_area;
+		} else {
+			if (!(vma->vm_flags & VM_READ))
+				goto bad_area;
+		}
+	}
+
+	/*
+	 * If for any reason at all we couldn't handle the fault,
+	 * make sure we exit gracefully rather than endlessly redo
+	 * the fault.
+	 */
+survive:
+	switch (handle_mm_fault(mm, vma, address, writeaccess)) {
+	case 1:
+		tsk->min_flt++;
+		break;
+	case 2:
+		tsk->maj_flt++;
+		break;
+	case 0:
+		goto do_sigbus;
+	default:
+		goto out_of_memory;
+	}
+	/* If we get here, the page fault has been handled.  Do the TLB refill
+	   now from the newly-setup PTE, to avoid having to fault again right
+	   away on the same instruction. */
+	pte = lookup_pte (mm, address);
+	if (!pte) {
+		/* From empirical evidence, we can get here, due to
+		   !pte_present(pte).  (e.g. if a swap-in occurs, and the page
+		   is swapped back out again before the process that wanted it
+		   gets rescheduled?) */
+		goto no_pte;
+	}
+
+	__do_tlb_refill(address, textaccess, pte);
+
+no_pte:
+
+	up_read(&mm->mmap_sem);
+	return;
+
+/*
+ * Something tried to access memory that isn't in our memory map..
+ * Fix it, but check if it's kernel or user first..
+ */
+bad_area:
+#ifdef DEBUG_FAULT
+	printk("fault:bad area\n");
+#endif
+	up_read(&mm->mmap_sem);
+
+	if (user_mode(regs)) {
+		static int count=0;
+		siginfo_t info;
+		if (count < 4) {
+			/* This is really to help debug faults when starting
+			 * usermode, so only need a few */
+			count++;
+			printk("user mode bad_area address=%08lx pid=%d (%s) pc=%08lx\n",
+				address, current->pid, current->comm,
+				(unsigned long) regs->pc);
+#if 0
+			show_regs(regs);
+#endif
+		}
+		if (tsk->pid == 1) {
+			panic("INIT had user mode bad_area\n");
+		}
+		tsk->thread.address = address;
+		tsk->thread.error_code = writeaccess;
+		info.si_signo = SIGSEGV;
+		info.si_errno = 0;
+		info.si_addr = (void *) address;
+		force_sig_info(SIGSEGV, &info, tsk);
+		return;
+	}
+
+no_context:
+#ifdef DEBUG_FAULT
+	printk("fault:No context\n");
+#endif
+	/* Are we prepared to handle this kernel fault?  */
+	fixup = search_exception_tables(regs->pc);
+	if (fixup) {
+		regs->pc = fixup->fixup;
+		return;
+	}
+
+/*
+ * Oops. The kernel tried to access some bad page. We'll have to
+ * terminate things with extreme prejudice.
+ *
+ */
+	if (address < PAGE_SIZE)
+		printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference");
+	else
+		printk(KERN_ALERT "Unable to handle kernel paging request");
+	printk(" at virtual address %08lx\n", address);
+	printk(KERN_ALERT "pc = %08Lx%08Lx\n", regs->pc >> 32, regs->pc & 0xffffffff);
+	die("Oops", regs, writeaccess);
+	do_exit(SIGKILL);
+
+/*
+ * We ran out of memory, or some other thing happened to us that made
+ * us unable to handle the page fault gracefully.
+ */
+out_of_memory:
+	if (current->pid == 1) {
+		panic("INIT out of memory\n");
+		yield();
+		goto survive;
+	}
+	printk("fault:Out of memory\n");
+	up_read(&mm->mmap_sem);
+	if (current->pid == 1) {
+		yield();
+		down_read(&mm->mmap_sem);
+		goto survive;
+	}
+	printk("VM: killing process %s\n", tsk->comm);
+	if (user_mode(regs))
+		do_exit(SIGKILL);
+	goto no_context;
+
+do_sigbus:
+	printk("fault:Do sigbus\n");
+	up_read(&mm->mmap_sem);
+
+	/*
+	 * Send a sigbus, regardless of whether we were in kernel
+	 * or user mode.
+	 */
+	tsk->thread.address = address;
+	tsk->thread.error_code = writeaccess;
+	tsk->thread.trap_no = 14;
+	force_sig(SIGBUS, tsk);
+
+	/* Kernel mode? Handle exceptions or die */
+	if (!user_mode(regs))
+		goto no_context;
+}
+
+
+void flush_tlb_all(void);
+
+void update_mmu_cache(struct vm_area_struct * vma,
+			unsigned long address, pte_t pte)
+{
+#if defined(CONFIG_SH64_PROC_TLB)
+	++calls_to_update_mmu_cache;
+#endif
+
+	/*
+	 * This appears to get called once for every pte entry that gets
+	 * established => I don't think it's efficient to try refilling the
+	 * TLBs with the pages - some may not get accessed even.  Also, for
+	 * executable pages, it is impossible to determine reliably here which
+	 * TLB they should be mapped into (or both even).
+	 *
+	 * So, just do nothing here and handle faults on demand.  In the
+	 * TLBMISS handling case, the refill is now done anyway after the pte
+	 * has been fixed up, so that deals with most useful cases.
+	 */
+}
+
+static void __flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
+{
+	unsigned long long match, pteh=0, lpage;
+	unsigned long tlb;
+	struct mm_struct *mm;
+
+	mm = vma->vm_mm;
+
+	if (mm->context == NO_CONTEXT)
+		return;
+
+	/*
+	 * Sign-extend based on neff.
+	 */
+	lpage = (page & NEFF_SIGN) ? (page | NEFF_MASK) : page;
+	match = ((mm->context & MMU_CONTEXT_ASID_MASK) << PTEH_ASID_SHIFT) | PTEH_VALID;
+	match |= lpage;
+
+        /* Do ITLB : don't bother for pages in non-exectutable VMAs */
+	if (vma->vm_flags & VM_EXEC) {
+		for_each_itlb_entry(tlb) {
+			asm volatile ("getcfg	%1, 0, %0"
+				      : "=r" (pteh)
+				      : "r" (tlb) );
+
+			if (pteh == match) {
+				__flush_tlb_slot(tlb);
+				break;
+			}
+
+		}
+	}
+
+        /* Do DTLB : any page could potentially be in here. */
+	for_each_dtlb_entry(tlb) {
+		asm volatile ("getcfg	%1, 0, %0"
+			      : "=r" (pteh)
+			      : "r" (tlb) );
+
+		if (pteh == match) {
+			__flush_tlb_slot(tlb);
+			break;
+		}
+
+	}
+}
+
+void flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
+{
+	unsigned long flags;
+
+#if defined(CONFIG_SH64_PROC_TLB)
+        ++calls_to_flush_tlb_page;
+#endif
+
+	if (vma->vm_mm) {
+		page &= PAGE_MASK;
+		local_irq_save(flags);
+		__flush_tlb_page(vma, page);
+		local_irq_restore(flags);
+	}
+}
+
+void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
+		     unsigned long end)
+{
+	unsigned long flags;
+	unsigned long long match, pteh=0, pteh_epn, pteh_low;
+	unsigned long tlb;
+	struct mm_struct *mm;
+
+	mm = vma->vm_mm;
+
+#if defined(CONFIG_SH64_PROC_TLB)
+	++calls_to_flush_tlb_range;
+
+	{
+		unsigned long size = (end - 1) - start;
+		size >>= 12; /* divide by PAGE_SIZE */
+		size++; /* end=start+4096 => 1 page */
+		switch (size) {
+		  case  1        : flush_tlb_range_1++;     break;
+		  case  2        : flush_tlb_range_2++;     break;
+		  case  3 ...  4 : flush_tlb_range_3_4++;   break;
+		  case  5 ...  7 : flush_tlb_range_5_7++;   break;
+		  case  8 ... 11 : flush_tlb_range_8_11++;  break;
+		  case 12 ... 15 : flush_tlb_range_12_15++; break;
+		  default        : flush_tlb_range_16_up++; break;
+		}
+	}
+#endif
+
+	if (mm->context == NO_CONTEXT)
+		return;
+
+	local_irq_save(flags);
+
+	start &= PAGE_MASK;
+	end &= PAGE_MASK;
+
+	match = ((mm->context & MMU_CONTEXT_ASID_MASK) << PTEH_ASID_SHIFT) | PTEH_VALID;
+
+	/* Flush ITLB */
+	for_each_itlb_entry(tlb) {
+		asm volatile ("getcfg	%1, 0, %0"
+			      : "=r" (pteh)
+			      : "r" (tlb) );
+
+		pteh_epn = pteh & PAGE_MASK;
+		pteh_low = pteh & ~PAGE_MASK;
+
+		if (pteh_low == match && pteh_epn >= start && pteh_epn <= end)
+			__flush_tlb_slot(tlb);
+	}
+
+	/* Flush DTLB */
+	for_each_dtlb_entry(tlb) {
+		asm volatile ("getcfg	%1, 0, %0"
+			      : "=r" (pteh)
+			      : "r" (tlb) );
+
+		pteh_epn = pteh & PAGE_MASK;
+		pteh_low = pteh & ~PAGE_MASK;
+
+		if (pteh_low == match && pteh_epn >= start && pteh_epn <= end)
+			__flush_tlb_slot(tlb);
+	}
+
+	local_irq_restore(flags);
+}
+
+void flush_tlb_mm(struct mm_struct *mm)
+{
+	unsigned long flags;
+
+#if defined(CONFIG_SH64_PROC_TLB)
+	++calls_to_flush_tlb_mm;
+#endif
+
+	if (mm->context == NO_CONTEXT)
+		return;
+
+	local_irq_save(flags);
+
+	mm->context=NO_CONTEXT;
+	if(mm==current->mm)
+		activate_context(mm);
+
+	local_irq_restore(flags);
+
+}
+
+void flush_tlb_all(void)
+{
+	/* Invalidate all, including shared pages, excluding fixed TLBs */
+
+	unsigned long flags, tlb;
+
+#if defined(CONFIG_SH64_PROC_TLB)
+	++calls_to_flush_tlb_all;
+#endif
+
+	local_irq_save(flags);
+
+	/* Flush each ITLB entry */
+	for_each_itlb_entry(tlb) {
+		__flush_tlb_slot(tlb);
+	}
+
+	/* Flush each DTLB entry */
+	for_each_dtlb_entry(tlb) {
+		__flush_tlb_slot(tlb);
+	}
+
+	local_irq_restore(flags);
+}
+
+void flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+        /* FIXME: Optimize this later.. */
+        flush_tlb_all();
+}
+
+#if defined(CONFIG_SH64_PROC_TLB)
+/* Procfs interface to read the performance information */
+
+static int
+tlb_proc_info(char *buf, char **start, off_t fpos, int length, int *eof, void *data)
+{
+  int len=0;
+  len += sprintf(buf+len, "do_fast_page_fault   called %12lld times\n", calls_to_do_fast_page_fault);
+  len += sprintf(buf+len, "do_slow_page_fault   called %12lld times\n", calls_to_do_slow_page_fault);
+  len += sprintf(buf+len, "update_mmu_cache     called %12lld times\n", calls_to_update_mmu_cache);
+  len += sprintf(buf+len, "flush_tlb_page       called %12lld times\n", calls_to_flush_tlb_page);
+  len += sprintf(buf+len, "flush_tlb_range      called %12lld times\n", calls_to_flush_tlb_range);
+  len += sprintf(buf+len, "flush_tlb_mm         called %12lld times\n", calls_to_flush_tlb_mm);
+  len += sprintf(buf+len, "flush_tlb_all        called %12lld times\n", calls_to_flush_tlb_all);
+  len += sprintf(buf+len, "flush_tlb_range_sizes\n"
+                          " 1      : %12lld\n"
+                          " 2      : %12lld\n"
+                          " 3 -  4 : %12lld\n"
+                          " 5 -  7 : %12lld\n"
+                          " 8 - 11 : %12lld\n"
+                          "12 - 15 : %12lld\n"
+                          "16+     : %12lld\n",
+                          flush_tlb_range_1, flush_tlb_range_2, flush_tlb_range_3_4,
+                          flush_tlb_range_5_7, flush_tlb_range_8_11, flush_tlb_range_12_15,
+                          flush_tlb_range_16_up);
+  len += sprintf(buf+len, "page not present           %12lld times\n", page_not_present);
+  *eof = 1;
+  return len;
+}
+
+static int __init register_proc_tlb(void)
+{
+  create_proc_read_entry("tlb", 0, NULL, tlb_proc_info, NULL);
+  return 0;
+}
+
+__initcall(register_proc_tlb);
+
+#endif