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-rw-r--r--arch/arm26/mm/fault.c312
1 files changed, 0 insertions, 312 deletions
diff --git a/arch/arm26/mm/fault.c b/arch/arm26/mm/fault.c
deleted file mode 100644
index dec638a0c8d..00000000000
--- a/arch/arm26/mm/fault.c
+++ /dev/null
@@ -1,312 +0,0 @@
-/*
- * linux/arch/arm26/mm/fault.c
- *
- * Copyright (C) 1995 Linus Torvalds
- * Modifications for ARM processor (c) 1995-2001 Russell King
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-#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/interrupt.h>
-#include <linux/proc_fs.h>
-#include <linux/init.h>
-
-#include <asm/system.h>
-#include <asm/pgtable.h>
-#include <asm/uaccess.h> //FIXME this header may be bogusly included
-
-#include "fault.h"
-
-#define FAULT_CODE_LDRSTRPOST 0x80
-#define FAULT_CODE_LDRSTRPRE 0x40
-#define FAULT_CODE_LDRSTRREG 0x20
-#define FAULT_CODE_LDMSTM 0x10
-#define FAULT_CODE_LDCSTC 0x08
-#define FAULT_CODE_PREFETCH 0x04
-#define FAULT_CODE_WRITE 0x02
-#define FAULT_CODE_FORCECOW 0x01
-
-#define DO_COW(m) ((m) & (FAULT_CODE_WRITE|FAULT_CODE_FORCECOW))
-#define READ_FAULT(m) (!((m) & FAULT_CODE_WRITE))
-#define DEBUG
-/*
- * This is useful to dump out the page tables associated with
- * 'addr' in mm 'mm'.
- */
-void show_pte(struct mm_struct *mm, unsigned long addr)
-{
- pgd_t *pgd;
-
- if (!mm)
- mm = &init_mm;
-
- printk(KERN_ALERT "pgd = %p\n", mm->pgd);
- pgd = pgd_offset(mm, addr);
- printk(KERN_ALERT "[%08lx] *pgd=%08lx", addr, pgd_val(*pgd));
-
- do {
- pmd_t *pmd;
- pte_t *pte;
-
- pmd = pmd_offset(pgd, addr);
-
- if (pmd_none(*pmd))
- break;
-
- if (pmd_bad(*pmd)) {
- printk("(bad)");
- break;
- }
-
- /* We must not map this if we have highmem enabled */
- /* FIXME */
- pte = pte_offset_map(pmd, addr);
- printk(", *pte=%08lx", pte_val(*pte));
- pte_unmap(pte);
- } while(0);
-
- printk("\n");
-}
-
-/*
- * Oops. The kernel tried to access some page that wasn't present.
- */
-static void
-__do_kernel_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr,
- struct pt_regs *regs)
-{
- /*
- * Are we prepared to handle this kernel fault?
- */
- if (fixup_exception(regs))
- return;
-
- /*
- * No handler, we'll have to terminate things with extreme prejudice.
- */
- bust_spinlocks(1);
- printk(KERN_ALERT
- "Unable to handle kernel %s at virtual address %08lx\n",
- (addr < PAGE_SIZE) ? "NULL pointer dereference" :
- "paging request", addr);
-
- show_pte(mm, addr);
- die("Oops", regs, fsr);
- bust_spinlocks(0);
- do_exit(SIGKILL);
-}
-
-/*
- * Something tried to access memory that isn't in our memory map..
- * User mode accesses just cause a SIGSEGV
- */
-static void
-__do_user_fault(struct task_struct *tsk, unsigned long addr,
- unsigned int fsr, int code, struct pt_regs *regs)
-{
- struct siginfo si;
-
-#ifdef CONFIG_DEBUG_USER
- printk("%s: unhandled page fault at 0x%08lx, code 0x%03x\n",
- tsk->comm, addr, fsr);
- show_pte(tsk->mm, addr);
- show_regs(regs);
- //dump_backtrace(regs, tsk); // FIXME ARM32 dropped this - why?
- while(1); //FIXME - hack to stop debug going nutso
-#endif
-
- tsk->thread.address = addr;
- tsk->thread.error_code = fsr;
- tsk->thread.trap_no = 14;
- si.si_signo = SIGSEGV;
- si.si_errno = 0;
- si.si_code = code;
- si.si_addr = (void *)addr;
- force_sig_info(SIGSEGV, &si, tsk);
-}
-
-static int
-__do_page_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr,
- struct task_struct *tsk)
-{
- struct vm_area_struct *vma;
- int fault, mask;
-
- vma = find_vma(mm, addr);
- fault = -2; /* bad map area */
- if (!vma)
- goto out;
- if (vma->vm_start > addr)
- goto check_stack;
-
- /*
- * Ok, we have a good vm_area for this
- * memory access, so we can handle it.
- */
-good_area:
- if (READ_FAULT(fsr)) /* read? */
- mask = VM_READ|VM_EXEC|VM_WRITE;
- else
- mask = VM_WRITE;
-
- fault = -1; /* bad access type */
- if (!(vma->vm_flags & mask))
- goto out;
-
- /*
- * If for any reason at all we couldn't handle
- * the fault, make sure we exit gracefully rather
- * than endlessly redo the fault.
- */
-survive:
- fault = handle_mm_fault(mm, vma, addr & PAGE_MASK, DO_COW(fsr));
- if (unlikely(fault & VM_FAULT_ERROR)) {
- if (fault & VM_FAULT_OOM)
- goto out_of_memory;
- else if (fault & VM_FAULT_SIGBUS)
- return fault;
- BUG();
- }
- if (fault & VM_FAULT_MAJOR)
- tsk->maj_flt++;
- else
- tsk->min_flt++;
- return fault;
-
-out_of_memory:
- fault = -3; /* out of memory */
- if (!is_init(tsk))
- goto out;
-
- /*
- * If we are out of memory for pid1,
- * sleep for a while and retry
- */
- yield();
- goto survive;
-
-check_stack:
- if (vma->vm_flags & VM_GROWSDOWN && !expand_stack(vma, addr))
- goto good_area;
-out:
- return fault;
-}
-
-int do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
-{
- struct task_struct *tsk;
- struct mm_struct *mm;
- int fault;
-
- tsk = current;
- mm = tsk->mm;
-
- /*
- * If we're in an interrupt or have no user
- * context, we must not take the fault..
- */
- if (in_atomic() || !mm)
- goto no_context;
-
- down_read(&mm->mmap_sem);
- fault = __do_page_fault(mm, addr, fsr, tsk);
- up_read(&mm->mmap_sem);
-
- /*
- * Handle the "normal" case first
- */
- if (likely(!(fault & VM_FAULT_ERROR)))
- return 0;
- if (fault & VM_FAULT_SIGBUS)
- goto do_sigbus;
- /* else VM_FAULT_OOM */
-
- /*
- * If we are in kernel mode at this point, we
- * have no context to handle this fault with.
- * FIXME - is this test right?
- */
- if (!user_mode(regs)){
- goto no_context;
- }
-
- if (fault == -3) {
- /*
- * We ran out of memory, or some other thing happened to
- * us that made us unable to handle the page fault gracefully.
- */
- printk("VM: killing process %s\n", tsk->comm);
- do_exit(SIGKILL);
- }
- else{
- __do_user_fault(tsk, addr, fsr, fault == -1 ? SEGV_ACCERR : SEGV_MAPERR, regs);
- }
-
- return 0;
-
-
-/*
- * We ran out of memory, or some other thing happened to us that made
- * us unable to handle the page fault gracefully.
- */
-do_sigbus:
- /*
- * Send a sigbus, regardless of whether we were in kernel
- * or user mode.
- */
- tsk->thread.address = addr; //FIXME - need other bits setting?
- tsk->thread.error_code = fsr;
- tsk->thread.trap_no = 14;
- force_sig(SIGBUS, tsk);
-#ifdef CONFIG_DEBUG_USER
- printk(KERN_DEBUG "%s: sigbus at 0x%08lx, pc=0x%08lx\n",
- current->comm, addr, instruction_pointer(regs));
-#endif
-
- /* Kernel mode? Handle exceptions or die */
- if (user_mode(regs))
- return 0;
-
-no_context:
- __do_kernel_fault(mm, addr, fsr, regs);
- return 0;
-}
-
-/*
- * Handle a data abort. Note that we have to handle a range of addresses
- * on ARM2/3 for ldm. If both pages are zero-mapped, then we have to force
- * a copy-on-write. However, on the second page, we always force COW.
- */
-asmlinkage void
-do_DataAbort(unsigned long min_addr, unsigned long max_addr, int mode, struct pt_regs *regs)
-{
- do_page_fault(min_addr, mode, regs);
-
- if ((min_addr ^ max_addr) >> PAGE_SHIFT){
- do_page_fault(max_addr, mode | FAULT_CODE_FORCECOW, regs);
- }
-}
-
-asmlinkage int
-do_PrefetchAbort(unsigned long addr, struct pt_regs *regs)
-{
-#if 0
- if (the memc mapping for this page exists) {
- printk ("Page in, but got abort (undefined instruction?)\n");
- return 0;
- }
-#endif
- do_page_fault(addr, FAULT_CODE_PREFETCH, regs);
- return 1;
-}
-
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-24 20:57:28 +0000