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Diffstat (limited to 'arch/sh/mm/fault_32.c')
-rw-r--r--arch/sh/mm/fault_32.c374
1 files changed, 0 insertions, 374 deletions
diff --git a/arch/sh/mm/fault_32.c b/arch/sh/mm/fault_32.c
deleted file mode 100644
index 324eef93c900..000000000000
--- a/arch/sh/mm/fault_32.c
+++ /dev/null
@@ -1,374 +0,0 @@
-/*
- * Page fault handler for SH with an MMU.
- *
- * Copyright (C) 1999 Niibe Yutaka
- * Copyright (C) 2003 - 2009 Paul Mundt
- *
- * Based on linux/arch/i386/mm/fault.c:
- * Copyright (C) 1995 Linus Torvalds
- *
- * 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.
- */
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/hardirq.h>
-#include <linux/kprobes.h>
-#include <linux/perf_event.h>
-#include <asm/io_trapped.h>
-#include <asm/mmu_context.h>
-#include <asm/tlbflush.h>
-#include <asm/traps.h>
-
-static inline int notify_page_fault(struct pt_regs *regs, int trap)
-{
- int ret = 0;
-
- if (kprobes_built_in() && !user_mode(regs)) {
- preempt_disable();
- if (kprobe_running() && kprobe_fault_handler(regs, trap))
- ret = 1;
- preempt_enable();
- }
-
- return ret;
-}
-
-static inline pmd_t *vmalloc_sync_one(pgd_t *pgd, unsigned long address)
-{
- unsigned index = pgd_index(address);
- pgd_t *pgd_k;
- pud_t *pud, *pud_k;
- pmd_t *pmd, *pmd_k;
-
- pgd += index;
- pgd_k = init_mm.pgd + index;
-
- if (!pgd_present(*pgd_k))
- return NULL;
-
- pud = pud_offset(pgd, address);
- pud_k = pud_offset(pgd_k, address);
- if (!pud_present(*pud_k))
- return NULL;
-
- if (!pud_present(*pud))
- set_pud(pud, *pud_k);
-
- pmd = pmd_offset(pud, address);
- pmd_k = pmd_offset(pud_k, address);
- if (!pmd_present(*pmd_k))
- return NULL;
-
- if (!pmd_present(*pmd))
- set_pmd(pmd, *pmd_k);
- else {
- /*
- * The page tables are fully synchronised so there must
- * be another reason for the fault. Return NULL here to
- * signal that we have not taken care of the fault.
- */
- BUG_ON(pmd_page(*pmd) != pmd_page(*pmd_k));
- return NULL;
- }
-
- return pmd_k;
-}
-
-/*
- * Handle a fault on the vmalloc or module mapping area
- */
-static noinline int vmalloc_fault(unsigned long address)
-{
- pgd_t *pgd_k;
- pmd_t *pmd_k;
- pte_t *pte_k;
-
- /* Make sure we are in vmalloc/module/P3 area: */
- if (!(address >= VMALLOC_START && address < P3_ADDR_MAX))
- return -1;
-
- /*
- * Synchronize this task's top level page-table
- * with the 'reference' page table.
- *
- * Do _not_ use "current" here. We might be inside
- * an interrupt in the middle of a task switch..
- */
- pgd_k = get_TTB();
- pmd_k = vmalloc_sync_one(pgd_k, address);
- if (!pmd_k)
- return -1;
-
- pte_k = pte_offset_kernel(pmd_k, address);
- if (!pte_present(*pte_k))
- return -1;
-
- return 0;
-}
-
-static int fault_in_kernel_space(unsigned long address)
-{
- return address >= TASK_SIZE;
-}
-
-/*
- * 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 __kprobes do_page_fault(struct pt_regs *regs,
- unsigned long writeaccess,
- unsigned long address)
-{
- unsigned long vec;
- struct task_struct *tsk;
- struct mm_struct *mm;
- struct vm_area_struct * vma;
- int si_code;
- int fault;
- siginfo_t info;
-
- tsk = current;
- mm = tsk->mm;
- si_code = SEGV_MAPERR;
- vec = lookup_exception_vector();
-
- /*
- * We fault-in kernel-space virtual memory on-demand. The
- * 'reference' page table is init_mm.pgd.
- *
- * NOTE! We MUST NOT take any locks for this case. We may
- * be in an interrupt or a critical region, and should
- * only copy the information from the master page table,
- * nothing more.
- */
- if (unlikely(fault_in_kernel_space(address))) {
- if (vmalloc_fault(address) >= 0)
- return;
- if (notify_page_fault(regs, vec))
- return;
-
- goto bad_area_nosemaphore;
- }
-
- if (unlikely(notify_page_fault(regs, vec)))
- return;
-
- /* Only enable interrupts if they were on before the fault */
- if ((regs->sr & SR_IMASK) != SR_IMASK)
- local_irq_enable();
-
- perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
-
- /*
- * If we're in an interrupt, have no user context or are running
- * in an atomic region then we must not take the fault:
- */
- if (in_atomic() || !mm)
- goto no_context;
-
- down_read(&mm->mmap_sem);
-
- vma = find_vma(mm, address);
- if (!vma)
- goto bad_area;
- if (vma->vm_start <= address)
- goto good_area;
- if (!(vma->vm_flags & VM_GROWSDOWN))
- goto bad_area;
- if (expand_stack(vma, address))
- goto bad_area;
-
- /*
- * Ok, we have a good vm_area for this memory access, so
- * we can handle it..
- */
-good_area:
- si_code = SEGV_ACCERR;
- if (writeaccess) {
- if (!(vma->vm_flags & VM_WRITE))
- goto bad_area;
- } else {
- if (!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)))
- 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.
- */
- fault = handle_mm_fault(mm, vma, address, writeaccess ? FAULT_FLAG_WRITE : 0);
- if (unlikely(fault & VM_FAULT_ERROR)) {
- if (fault & VM_FAULT_OOM)
- goto out_of_memory;
- else if (fault & VM_FAULT_SIGBUS)
- goto do_sigbus;
- BUG();
- }
- if (fault & VM_FAULT_MAJOR) {
- tsk->maj_flt++;
- perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1,
- regs, address);
- } else {
- tsk->min_flt++;
- perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1,
- regs, address);
- }
-
- 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:
- up_read(&mm->mmap_sem);
-
-bad_area_nosemaphore:
- if (user_mode(regs)) {
- 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;
- }
-
-no_context:
- /* Are we prepared to handle this kernel fault? */
- if (fixup_exception(regs))
- return;
-
- if (handle_trapped_io(regs, address))
- return;
-/*
- * Oops. The kernel tried to access some bad page. We'll have to
- * terminate things with extreme prejudice.
- *
- */
-
- bust_spinlocks(1);
-
- if (oops_may_print()) {
- unsigned long page;
-
- 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\n", regs->pc);
- page = (unsigned long)get_TTB();
- if (page) {
- page = ((__typeof__(page) *)page)[address >> PGDIR_SHIFT];
- printk(KERN_ALERT "*pde = %08lx\n", page);
- if (page & _PAGE_PRESENT) {
- page &= PAGE_MASK;
- address &= 0x003ff000;
- page = ((__typeof__(page) *)
- __va(page))[address >>
- PAGE_SHIFT];
- printk(KERN_ALERT "*pte = %08lx\n", page);
- }
- }
- }
-
- die("Oops", regs, writeaccess);
- bust_spinlocks(0);
- 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:
- up_read(&mm->mmap_sem);
- if (!user_mode(regs))
- goto no_context;
- pagefault_out_of_memory();
- return;
-
-do_sigbus:
- up_read(&mm->mmap_sem);
-
- /*
- * Send a sigbus, regardless of whether we were in kernel
- * or user mode.
- */
- 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;
-}
-
-/*
- * Called with interrupts disabled.
- */
-asmlinkage int __kprobes
-handle_tlbmiss(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;
-
- /*
- * 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);
- } else {
- if (unlikely(address >= TASK_SIZE || !current->mm))
- return 1;
-
- pgd = pgd_offset(current->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;
- pte = pte_offset_kernel(pmd, address);
- entry = *pte;
- if (unlikely(pte_none(entry) || pte_not_present(entry)))
- return 1;
- if (unlikely(writeaccess && !pte_write(entry)))
- return 1;
-
- if (writeaccess)
- entry = pte_mkdirty(entry);
- entry = pte_mkyoung(entry);
-
- set_pte(pte, entry);
-
-#if defined(CONFIG_CPU_SH4) && !defined(CONFIG_SMP)
- /*
- * SH-4 does not set MMUCR.RC to the corresponding TLB entry in
- * the case of an initial page write exception, so we need to
- * flush it in order to avoid potential TLB entry duplication.
- */
- if (writeaccess == 2)
- local_flush_tlb_one(get_asid(), address & PAGE_MASK);
-#endif
-
- update_mmu_cache(NULL, address, pte);
-
- return 0;
-}
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