Merge branch 'intx' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/misc-2.6
[pandora-kernel.git] / arch / sh / mm / fault.c
index 507f289..716ebf5 100644 (file)
@@ -26,13 +26,19 @@ extern void die(const char *,struct pt_regs *,long);
  * 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();
+       local_irq_enable();
 
 #ifdef CONFIG_SH_KGDB
        if (kgdb_nofault && kgdb_bus_err_hook)
@@ -41,6 +47,46 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long writeaccess,
 
        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
@@ -65,6 +111,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long writeaccess,
  * we can handle it..
  */
 good_area:
+       si_code = SEGV_ACCERR;
        if (writeaccess) {
                if (!(vma->vm_flags & VM_WRITE))
                        goto bad_area;
@@ -104,10 +151,13 @@ survive:
 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;
        }
 
@@ -127,11 +177,9 @@ no_context:
                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;
@@ -149,7 +197,7 @@ no_context:
  */
 out_of_memory:
        up_read(&mm->mmap_sem);
-       if (current->pid == 1) {
+       if (is_init(current)) {
                yield();
                down_read(&mm->mmap_sem);
                goto survive;
@@ -166,98 +214,13 @@ do_sigbus:
         * 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))
                goto no_context;
 }
-
-#ifdef CONFIG_SH_STORE_QUEUES
-/*
- * This is a special case for the SH-4 store queues, as pages for this
- * space still need to be faulted in before it's possible to flush the
- * store queue cache for writeout to the remapped region.
- */
-#define P3_ADDR_MAX            (P4SEG_STORE_QUE + 0x04000000)
-#else
-#define P3_ADDR_MAX            P4SEG
-#endif
-
-/*
- * Called with interrupts disabled.
- */
-asmlinkage int __kprobes __do_page_fault(struct pt_regs *regs,
-                                        unsigned long writeaccess,
-                                        unsigned long address)
-{
-       pgd_t *pgd;
-       pud_t *pud;
-       pmd_t *pmd;
-       pte_t *pte;
-       pte_t entry;
-       struct mm_struct *mm = current->mm;
-       spinlock_t *ptl;
-       int ret = 1;
-
-#ifdef CONFIG_SH_KGDB
-       if (kgdb_nofault && kgdb_bus_err_hook)
-               kgdb_bus_err_hook();
-#endif
-
-       /*
-        * We don't take page faults for P1, P2, and parts of P4, these
-        * are always mapped, whether it be due to legacy behaviour in
-        * 29-bit mode, or due to PMB configuration in 32-bit mode.
-        */
-       if (address >= P3SEG && address < P3_ADDR_MAX) {
-               pgd = pgd_offset_k(address);
-               mm = NULL;
-       } else {
-               if (unlikely(address >= TASK_SIZE || !mm))
-                       return 1;
-
-               pgd = pgd_offset(mm, address);
-       }
-
-       pud = pud_offset(pgd, address);
-       if (pud_none_or_clear_bad(pud))
-               return 1;
-       pmd = pmd_offset(pud, address);
-       if (pmd_none_or_clear_bad(pmd))
-               return 1;
-
-       if (mm)
-               pte = pte_offset_map_lock(mm, pmd, address, &ptl);
-       else
-               pte = pte_offset_kernel(pmd, address);
-
-       entry = *pte;
-       if (unlikely(pte_none(entry) || pte_not_present(entry)))
-               goto unlock;
-       if (unlikely(writeaccess && !pte_write(entry)))
-               goto unlock;
-
-       if (writeaccess)
-               entry = pte_mkdirty(entry);
-       entry = pte_mkyoung(entry);
-
-#ifdef CONFIG_CPU_SH4
-       /*
-        * ITLB is not affected by "ldtlb" instruction.
-        * So, we need to flush the entry by ourselves.
-        */
-       __flush_tlb_page(get_asid(), address & PAGE_MASK);
-#endif
-
-       set_pte(pte, entry);
-       update_mmu_cache(NULL, address, entry);
-       ret = 0;
-unlock:
-       if (mm)
-               pte_unmap_unlock(pte, ptl);
-       return ret;
-}