* Page fault handler for SH with an MMU.
*
* Copyright (C) 1999 Niibe Yutaka
- * Copyright (C) 2003 Paul Mundt
+ * Copyright (C) 2003 - 2007 Paul Mundt
*
* Based on linux/arch/i386/mm/fault.c:
* Copyright (C) 1995 Linus Torvalds
#include <linux/mm.h>
#include <linux/hardirq.h>
#include <linux/kprobes.h>
+#include <asm/kdebug.h>
#include <asm/system.h>
#include <asm/mmu_context.h>
+#include <asm/tlbflush.h>
#include <asm/kgdb.h>
-extern void die(const char *,struct pt_regs *,long);
+#ifdef CONFIG_KPROBES
+ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain);
+
+/* Hook to register for page fault notifications */
+int register_page_fault_notifier(struct notifier_block *nb)
+{
+ return atomic_notifier_chain_register(¬ify_page_fault_chain, nb);
+}
+
+int unregister_page_fault_notifier(struct notifier_block *nb)
+{
+ return atomic_notifier_chain_unregister(¬ify_page_fault_chain, nb);
+}
+
+static inline int notify_page_fault(enum die_val val, struct pt_regs *regs,
+ int trap, int sig)
+{
+ struct die_args args = {
+ .regs = regs,
+ .trapnr = trap,
+ };
+ return atomic_notifier_call_chain(¬ify_page_fault_chain, val, &args);
+}
+#else
+static inline int notify_page_fault(enum die_val val, struct pt_regs *regs,
+ int trap, int sig)
+{
+ return NOTIFY_DONE;
+}
+#endif
/*
* 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 address)
+asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
+ unsigned long writeaccess,
+ unsigned long address)
{
struct task_struct *tsk;
struct mm_struct *mm;
struct vm_area_struct * vma;
unsigned long page;
+ int si_code;
+ siginfo_t info;
+
+ trace_hardirqs_on();
+
+ if (notify_page_fault(DIE_PAGE_FAULT, regs,
+ writeaccess, SIGSEGV) == NOTIFY_STOP)
+ return;
+
+ local_irq_enable();
#ifdef CONFIG_SH_KGDB
if (kgdb_nofault && kgdb_bus_err_hook)
tsk = current;
mm = tsk->mm;
+ si_code = SEGV_MAPERR;
+
+ if (unlikely(address >= TASK_SIZE)) {
+ /*
+ * Synchronize this task's top level page-table
+ * with the 'reference' page table.
+ *
+ * Do _not_ use "tsk" here. We might be inside
+ * an interrupt in the middle of a task switch..
+ */
+ int offset = pgd_index(address);
+ pgd_t *pgd, *pgd_k;
+ pud_t *pud, *pud_k;
+ pmd_t *pmd, *pmd_k;
+
+ pgd = get_TTB() + offset;
+ pgd_k = swapper_pg_dir + offset;
+
+ /* This will never happen with the folded page table. */
+ if (!pgd_present(*pgd)) {
+ if (!pgd_present(*pgd_k))
+ goto bad_area_nosemaphore;
+ set_pgd(pgd, *pgd_k);
+ return;
+ }
+
+ pud = pud_offset(pgd, address);
+ pud_k = pud_offset(pgd_k, address);
+ if (pud_present(*pud) || !pud_present(*pud_k))
+ goto bad_area_nosemaphore;
+ set_pud(pud, *pud_k);
+
+ pmd = pmd_offset(pud, address);
+ pmd_k = pmd_offset(pud_k, address);
+ if (pmd_present(*pmd) || !pmd_present(*pmd_k))
+ goto bad_area_nosemaphore;
+ set_pmd(pmd, *pmd_k);
+
+ return;
+ }
/*
* If we're in an interrupt or have no user
* we can handle it..
*/
good_area:
+ si_code = SEGV_ACCERR;
if (writeaccess) {
if (!(vma->vm_flags & VM_WRITE))
goto bad_area;
bad_area:
up_read(&mm->mmap_sem);
+bad_area_nosemaphore:
if (user_mode(regs)) {
- tsk->thread.address = address;
- tsk->thread.error_code = writeaccess;
- force_sig(SIGSEGV, tsk);
+ info.si_signo = SIGSEGV;
+ info.si_errno = 0;
+ info.si_code = si_code;
+ info.si_addr = (void *) address;
+ force_sig_info(SIGSEGV, &info, tsk);
return;
}
printk(KERN_ALERT "Unable to handle kernel paging request");
printk(" at virtual address %08lx\n", address);
printk(KERN_ALERT "pc = %08lx\n", regs->pc);
- asm volatile("mov.l %1, %0"
- : "=r" (page)
- : "m" (__m(MMU_TTB)));
+ page = (unsigned long)get_TTB();
if (page) {
- page = ((unsigned long *) page)[address >> 22];
+ page = ((unsigned long *) page)[address >> PGDIR_SHIFT];
printk(KERN_ALERT "*pde = %08lx\n", page);
if (page & _PAGE_PRESENT) {
page &= PAGE_MASK;
* 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);
+ info.si_signo = SIGBUS;
+ info.si_errno = 0;
+ info.si_code = BUS_ADRERR;
+ info.si_addr = (void *)address;
+ force_sig_info(SIGBUS, &info, tsk);
/* Kernel mode? Handle exceptions or die */
if (!user_mode(regs))
* ITLB is not affected by "ldtlb" instruction.
* So, we need to flush the entry by ourselves.
*/
- __flush_tlb_page(get_asid(), address & PAGE_MASK);
+ local_flush_tlb_one(get_asid(), address & PAGE_MASK);
#endif
set_pte(pte, entry);
projects / linux-drm-fsl-dcu.git / blobdiff