diff options
Diffstat (limited to 'arch/m32r/mm/fault.c')
| -rw-r--r-- | arch/m32r/mm/fault.c | 550 |
1 files changed, 0 insertions, 550 deletions
diff --git a/arch/m32r/mm/fault.c b/arch/m32r/mm/fault.c deleted file mode 100644 index 46d9a5ca0e3a..000000000000 --- a/arch/m32r/mm/fault.c +++ /dev/null @@ -1,550 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * linux/arch/m32r/mm/fault.c - * - * Copyright (c) 2001, 2002 Hitoshi Yamamoto, and H. Kondo - * Copyright (c) 2004 Naoto Sugai, NIIBE Yutaka - * - * Some code taken from i386 version. - * Copyright (C) 1995 Linus Torvalds - */ - -#include <linux/signal.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/interrupt.h> -#include <linux/init.h> -#include <linux/tty.h> -#include <linux/vt_kern.h> /* For unblank_screen() */ -#include <linux/highmem.h> -#include <linux/extable.h> -#include <linux/uaccess.h> - -#include <asm/m32r.h> -#include <asm/hardirq.h> -#include <asm/mmu_context.h> -#include <asm/tlbflush.h> - -extern void die(const char *, struct pt_regs *, long); - -#ifndef CONFIG_SMP -asmlinkage unsigned int tlb_entry_i_dat; -asmlinkage unsigned int tlb_entry_d_dat; -#define tlb_entry_i tlb_entry_i_dat -#define tlb_entry_d tlb_entry_d_dat -#else -unsigned int tlb_entry_i_dat[NR_CPUS]; -unsigned int tlb_entry_d_dat[NR_CPUS]; -#define tlb_entry_i tlb_entry_i_dat[smp_processor_id()] -#define tlb_entry_d tlb_entry_d_dat[smp_processor_id()] -#endif - -extern void init_tlb(void); - -/*======================================================================* - * do_page_fault() - *======================================================================* - * This routine handles page faults. It determines the address, - * and the problem, and then passes it off to one of the appropriate - * routines. - * - * ARGUMENT: - * regs : M32R SP reg. - * error_code : See below - * address : M32R MMU MDEVA reg. (Operand ACE) - * : M32R BPC reg. (Instruction ACE) - * - * error_code : - * bit 0 == 0 means no page found, 1 means protection fault - * bit 1 == 0 means read, 1 means write - * bit 2 == 0 means kernel, 1 means user-mode - * bit 3 == 0 means data, 1 means instruction - *======================================================================*/ -#define ACE_PROTECTION 1 -#define ACE_WRITE 2 -#define ACE_USERMODE 4 -#define ACE_INSTRUCTION 8 - -asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code, - unsigned long address) -{ - struct task_struct *tsk; - struct mm_struct *mm; - struct vm_area_struct * vma; - unsigned long page, addr; - unsigned long flags = 0; - int fault; - siginfo_t info; - - /* - * If BPSW IE bit enable --> set PSW IE bit - */ - if (regs->psw & M32R_PSW_BIE) - local_irq_enable(); - - tsk = current; - - info.si_code = SEGV_MAPERR; - - /* - * 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. - * - * This verifies that the fault happens in kernel space - * (error_code & ACE_USERMODE) == 0, and that the fault was not a - * protection error (error_code & ACE_PROTECTION) == 0. - */ - if (address >= TASK_SIZE && !(error_code & ACE_USERMODE)) - goto vmalloc_fault; - - mm = tsk->mm; - - /* - * If we're in an interrupt or have no user context or have pagefaults - * disabled then we must not take the fault. - */ - if (faulthandler_disabled() || !mm) - goto bad_area_nosemaphore; - - if (error_code & ACE_USERMODE) - flags |= FAULT_FLAG_USER; - - /* When running in the kernel we expect faults to occur only to - * addresses in user space. All other faults represent errors in the - * kernel and should generate an OOPS. Unfortunately, in the case of an - * erroneous fault occurring in a code path which already holds mmap_sem - * we will deadlock attempting to validate the fault against the - * address space. Luckily the kernel only validly references user - * space from well defined areas of code, which are listed in the - * exceptions table. - * - * As the vast majority of faults will be valid we will only perform - * the source reference check when there is a possibility of a deadlock. - * Attempt to lock the address space, if we cannot we then validate the - * source. If this is invalid we can skip the address space check, - * thus avoiding the deadlock. - */ - if (!down_read_trylock(&mm->mmap_sem)) { - if ((error_code & ACE_USERMODE) == 0 && - !search_exception_tables(regs->psw)) - goto bad_area_nosemaphore; - 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 (error_code & ACE_USERMODE) { - /* - * accessing the stack below "spu" is always a bug. - * The "+ 4" is there due to the push instruction - * doing pre-decrement on the stack and that - * doesn't show up until later.. - */ - if (address + 4 < regs->spu) - 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: - info.si_code = SEGV_ACCERR; - switch (error_code & (ACE_WRITE|ACE_PROTECTION)) { - default: /* 3: write, present */ - /* fall through */ - case ACE_WRITE: /* write, not present */ - if (!(vma->vm_flags & VM_WRITE)) - goto bad_area; - flags |= FAULT_FLAG_WRITE; - break; - case ACE_PROTECTION: /* read, present */ - case 0: /* read, not present */ - if (!(vma->vm_flags & (VM_READ | VM_EXEC))) - goto bad_area; - } - - /* - * For instruction access exception, check if the area is executable - */ - if ((error_code & ACE_INSTRUCTION) && !(vma->vm_flags & VM_EXEC)) - 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. - */ - addr = (address & PAGE_MASK); - set_thread_fault_code(error_code); - fault = handle_mm_fault(vma, addr, flags); - if (unlikely(fault & VM_FAULT_ERROR)) { - if (fault & VM_FAULT_OOM) - goto out_of_memory; - else if (fault & VM_FAULT_SIGSEGV) - goto bad_area; - else if (fault & VM_FAULT_SIGBUS) - goto do_sigbus; - BUG(); - } - if (fault & VM_FAULT_MAJOR) - tsk->maj_flt++; - else - tsk->min_flt++; - set_thread_fault_code(0); - 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: - /* User mode accesses just cause a SIGSEGV */ - if (error_code & ACE_USERMODE) { - tsk->thread.address = address; - tsk->thread.error_code = error_code | (address >= TASK_SIZE); - tsk->thread.trap_no = 14; - info.si_signo = SIGSEGV; - info.si_errno = 0; - /* info.si_code has been set above */ - info.si_addr = (void __user *)address; - force_sig_info(SIGSEGV, &info, tsk); - return; - } - -no_context: - /* Are we prepared to handle this kernel fault? */ - if (fixup_exception(regs)) - return; - -/* - * Oops. The kernel tried to access some bad page. We'll have to - * terminate things with extreme prejudice. - */ - - bust_spinlocks(1); - - 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 " printing bpc:\n"); - printk("%08lx\n", regs->bpc); - page = *(unsigned long *)MPTB; - page = ((unsigned long *) page)[address >> PGDIR_SHIFT]; - printk(KERN_ALERT "*pde = %08lx\n", page); - if (page & _PAGE_PRESENT) { - page &= PAGE_MASK; - address &= 0x003ff000; - page = ((unsigned long *) __va(page))[address >> PAGE_SHIFT]; - printk(KERN_ALERT "*pte = %08lx\n", page); - } - die("Oops", regs, error_code); - 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 (!(error_code & ACE_USERMODE)) - goto no_context; - pagefault_out_of_memory(); - return; - -do_sigbus: - up_read(&mm->mmap_sem); - - /* Kernel mode? Handle exception or die */ - if (!(error_code & ACE_USERMODE)) - goto no_context; - - tsk->thread.address = address; - tsk->thread.error_code = error_code; - tsk->thread.trap_no = 14; - info.si_signo = SIGBUS; - info.si_errno = 0; - info.si_code = BUS_ADRERR; - info.si_addr = (void __user *)address; - force_sig_info(SIGBUS, &info, tsk); - return; - -vmalloc_fault: - { - /* - * 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; - pmd_t *pmd, *pmd_k; - pte_t *pte_k; - - pgd = (pgd_t *)*(unsigned long *)MPTB; - pgd = offset + (pgd_t *)pgd; - pgd_k = init_mm.pgd + offset; - - if (!pgd_present(*pgd_k)) - goto no_context; - - /* - * set_pgd(pgd, *pgd_k); here would be useless on PAE - * and redundant with the set_pmd() on non-PAE. - */ - - pmd = pmd_offset(pgd, address); - pmd_k = pmd_offset(pgd_k, address); - if (!pmd_present(*pmd_k)) - goto no_context; - set_pmd(pmd, *pmd_k); - - pte_k = pte_offset_kernel(pmd_k, address); - if (!pte_present(*pte_k)) - goto no_context; - - addr = (address & PAGE_MASK); - set_thread_fault_code(error_code); - update_mmu_cache(NULL, addr, pte_k); - set_thread_fault_code(0); - return; - } -} - -/*======================================================================* - * update_mmu_cache() - *======================================================================*/ -#define TLB_MASK (NR_TLB_ENTRIES - 1) -#define ITLB_END (unsigned long *)(ITLB_BASE + (NR_TLB_ENTRIES * 8)) -#define DTLB_END (unsigned long *)(DTLB_BASE + (NR_TLB_ENTRIES * 8)) -void update_mmu_cache(struct vm_area_struct *vma, unsigned long vaddr, - pte_t *ptep) -{ - volatile unsigned long *entry1, *entry2; - unsigned long pte_data, flags; - unsigned int *entry_dat; - int inst = get_thread_fault_code() & ACE_INSTRUCTION; - int i; - - /* Ptrace may call this routine. */ - if (vma && current->active_mm != vma->vm_mm) - return; - - local_irq_save(flags); - - vaddr = (vaddr & PAGE_MASK) | get_asid(); - - pte_data = pte_val(*ptep); - -#ifdef CONFIG_CHIP_OPSP - entry1 = (unsigned long *)ITLB_BASE; - for (i = 0; i < NR_TLB_ENTRIES; i++) { - if (*entry1++ == vaddr) { - set_tlb_data(entry1, pte_data); - break; - } - entry1++; - } - entry2 = (unsigned long *)DTLB_BASE; - for (i = 0; i < NR_TLB_ENTRIES; i++) { - if (*entry2++ == vaddr) { - set_tlb_data(entry2, pte_data); - break; - } - entry2++; - } -#else - /* - * Update TLB entries - * entry1: ITLB entry address - * entry2: DTLB entry address - */ - __asm__ __volatile__ ( - "seth %0, #high(%4) \n\t" - "st %2, @(%5, %0) \n\t" - "ldi %1, #1 \n\t" - "st %1, @(%6, %0) \n\t" - "add3 r4, %0, %7 \n\t" - ".fillinsn \n" - "1: \n\t" - "ld %1, @(%6, %0) \n\t" - "bnez %1, 1b \n\t" - "ld %0, @r4+ \n\t" - "ld %1, @r4 \n\t" - "st %3, @+%0 \n\t" - "st %3, @+%1 \n\t" - : "=&r" (entry1), "=&r" (entry2) - : "r" (vaddr), "r" (pte_data), "i" (MMU_REG_BASE), - "i" (MSVA_offset), "i" (MTOP_offset), "i" (MIDXI_offset) - : "r4", "memory" - ); -#endif - - if ((!inst && entry2 >= DTLB_END) || (inst && entry1 >= ITLB_END)) - goto notfound; - -found: - local_irq_restore(flags); - - return; - - /* Valid entry not found */ -notfound: - /* - * Update ITLB or DTLB entry - * entry1: TLB entry address - * entry2: TLB base address - */ - if (!inst) { - entry2 = (unsigned long *)DTLB_BASE; - entry_dat = &tlb_entry_d; - } else { - entry2 = (unsigned long *)ITLB_BASE; - entry_dat = &tlb_entry_i; - } - entry1 = entry2 + (((*entry_dat - 1) & TLB_MASK) << 1); - - for (i = 0 ; i < NR_TLB_ENTRIES ; i++) { - if (!(entry1[1] & 2)) /* Valid bit check */ - break; - - if (entry1 != entry2) - entry1 -= 2; - else - entry1 += TLB_MASK << 1; - } - - if (i >= NR_TLB_ENTRIES) { /* Empty entry not found */ - entry1 = entry2 + (*entry_dat << 1); - *entry_dat = (*entry_dat + 1) & TLB_MASK; - } - *entry1++ = vaddr; /* Set TLB tag */ - set_tlb_data(entry1, pte_data); - - goto found; -} - -/*======================================================================* - * flush_tlb_page() : flushes one page - *======================================================================*/ -void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page) -{ - if (vma->vm_mm && mm_context(vma->vm_mm) != NO_CONTEXT) { - unsigned long flags; - - local_irq_save(flags); - page &= PAGE_MASK; - page |= (mm_context(vma->vm_mm) & MMU_CONTEXT_ASID_MASK); - __flush_tlb_page(page); - local_irq_restore(flags); - } -} - -/*======================================================================* - * flush_tlb_range() : flushes a range of pages - *======================================================================*/ -void local_flush_tlb_range(struct vm_area_struct *vma, unsigned long start, - unsigned long end) -{ - struct mm_struct *mm; - - mm = vma->vm_mm; - if (mm_context(mm) != NO_CONTEXT) { - unsigned long flags; - int size; - - local_irq_save(flags); - size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT; - if (size > (NR_TLB_ENTRIES / 4)) { /* Too many TLB to flush */ - mm_context(mm) = NO_CONTEXT; - if (mm == current->mm) - activate_context(mm); - } else { - unsigned long asid; - - asid = mm_context(mm) & MMU_CONTEXT_ASID_MASK; - start &= PAGE_MASK; - end += (PAGE_SIZE - 1); - end &= PAGE_MASK; - - start |= asid; - end |= asid; - while (start < end) { - __flush_tlb_page(start); - start += PAGE_SIZE; - } - } - local_irq_restore(flags); - } -} - -/*======================================================================* - * flush_tlb_mm() : flushes the specified mm context TLB's - *======================================================================*/ -void local_flush_tlb_mm(struct mm_struct *mm) -{ - /* Invalidate all TLB of this process. */ - /* Instead of invalidating each TLB, we get new MMU context. */ - if (mm_context(mm) != NO_CONTEXT) { - unsigned long flags; - - local_irq_save(flags); - mm_context(mm) = NO_CONTEXT; - if (mm == current->mm) - activate_context(mm); - local_irq_restore(flags); - } -} - -/*======================================================================* - * flush_tlb_all() : flushes all processes TLBs - *======================================================================*/ -void local_flush_tlb_all(void) -{ - unsigned long flags; - - local_irq_save(flags); - __flush_tlb_all(); - local_irq_restore(flags); -} - -/*======================================================================* - * init_mmu() - *======================================================================*/ -void __init init_mmu(void) -{ - tlb_entry_i = 0; - tlb_entry_d = 0; - mmu_context_cache = MMU_CONTEXT_FIRST_VERSION; - set_asid(mmu_context_cache & MMU_CONTEXT_ASID_MASK); - *(volatile unsigned long *)MPTB = (unsigned long)swapper_pg_dir; -} |