diff options
Diffstat (limited to 'arch/sh/mm/fault_32.c')
-rw-r--r-- | arch/sh/mm/fault_32.c | 374 |
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 324eef93c90..00000000000 --- 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; -} |