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-rw-r--r--arch/avr32/mm/fault.c268
1 files changed, 0 insertions, 268 deletions
diff --git a/arch/avr32/mm/fault.c b/arch/avr32/mm/fault.c
deleted file mode 100644
index b3977e9208a3..000000000000
--- a/arch/avr32/mm/fault.c
+++ /dev/null
@@ -1,268 +0,0 @@
-/*
- * Copyright (C) 2004-2006 Atmel Corporation
- *
- * Based on linux/arch/sh/mm/fault.c:
- * Copyright (C) 1999 Niibe Yutaka
- *
- * 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/mm.h>
-#include <linux/extable.h>
-#include <linux/pagemap.h>
-#include <linux/kdebug.h>
-#include <linux/kprobes.h>
-#include <linux/uaccess.h>
-
-#include <asm/mmu_context.h>
-#include <asm/sysreg.h>
-#include <asm/tlb.h>
-
-#ifdef CONFIG_KPROBES
-static inline int notify_page_fault(struct pt_regs *regs, int trap)
-{
- int ret = 0;
-
- if (!user_mode(regs)) {
- if (kprobe_running() && kprobe_fault_handler(regs, trap))
- ret = 1;
- }
-
- return ret;
-}
-#else
-static inline int notify_page_fault(struct pt_regs *regs, int trap)
-{
- return 0;
-}
-#endif
-
-int exception_trace = 1;
-
-/*
- * This routine handles page faults. It determines the address and the
- * problem, and then passes it off to one of the appropriate routines.
- *
- * ecr is the Exception Cause Register. Possible values are:
- * 6: Protection fault (instruction access)
- * 15: Protection fault (read access)
- * 16: Protection fault (write access)
- * 20: Page not found (instruction access)
- * 24: Page not found (read access)
- * 28: Page not found (write access)
- */
-asmlinkage void do_page_fault(unsigned long ecr, struct pt_regs *regs)
-{
- struct task_struct *tsk;
- struct mm_struct *mm;
- struct vm_area_struct *vma;
- const struct exception_table_entry *fixup;
- unsigned long address;
- unsigned long page;
- long signr;
- int code;
- int fault;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
-
- if (notify_page_fault(regs, ecr))
- return;
-
- address = sysreg_read(TLBEAR);
-
- tsk = current;
- mm = tsk->mm;
-
- signr = SIGSEGV;
- code = SEGV_MAPERR;
-
- /*
- * If we're in an interrupt or have no user context, we must
- * not take the fault...
- */
- if (faulthandler_disabled() || !mm || regs->sr & SYSREG_BIT(GM))
- goto no_context;
-
- local_irq_enable();
-
- if (user_mode(regs))
- flags |= FAULT_FLAG_USER;
-retry:
- 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:
- code = SEGV_ACCERR;
-
- switch (ecr) {
- case ECR_PROTECTION_X:
- case ECR_TLB_MISS_X:
- if (!(vma->vm_flags & VM_EXEC))
- goto bad_area;
- break;
- case ECR_PROTECTION_R:
- case ECR_TLB_MISS_R:
- if (!(vma->vm_flags & (VM_READ | VM_WRITE | VM_EXEC)))
- goto bad_area;
- break;
- case ECR_PROTECTION_W:
- case ECR_TLB_MISS_W:
- if (!(vma->vm_flags & VM_WRITE))
- goto bad_area;
- flags |= FAULT_FLAG_WRITE;
- break;
- default:
- panic("Unhandled case %lu in do_page_fault!", ecr);
- }
-
- /*
- * 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(vma, address, flags);
-
- if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current))
- return;
-
- 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 (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_MAJOR)
- tsk->maj_flt++;
- else
- tsk->min_flt++;
- if (fault & VM_FAULT_RETRY) {
- flags &= ~FAULT_FLAG_ALLOW_RETRY;
- flags |= FAULT_FLAG_TRIED;
-
- /*
- * No need to up_read(&mm->mmap_sem) as we would have
- * already released it in __lock_page_or_retry() in
- * mm/filemap.c.
- */
- goto retry;
- }
- }
-
- 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);
-
- if (user_mode(regs)) {
- if (exception_trace && printk_ratelimit())
- printk("%s%s[%d]: segfault at %08lx pc %08lx "
- "sp %08lx ecr %lu\n",
- is_global_init(tsk) ? KERN_EMERG : KERN_INFO,
- tsk->comm, tsk->pid, address, regs->pc,
- regs->sp, ecr);
- _exception(SIGSEGV, regs, code, address);
- return;
- }
-
-no_context:
- /* Are we prepared to handle this kernel fault? */
- fixup = search_exception_tables(regs->pc);
- if (fixup) {
- regs->pc = fixup->fixup;
- return;
- }
-
- /*
- * Oops. The kernel tried to access some bad page. We'll have
- * to terminate things with extreme prejudice.
- */
- 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);
-
- page = sysreg_read(PTBR);
- printk(KERN_ALERT "ptbr = %08lx", page);
- if (address >= TASK_SIZE)
- page = (unsigned long)swapper_pg_dir;
- if (page) {
- page = ((unsigned long *)page)[address >> 22];
- printk(" pgd = %08lx", page);
- if (page & _PAGE_PRESENT) {
- page &= PAGE_MASK;
- address &= 0x003ff000;
- page = ((unsigned long *)__va(page))[address >> PAGE_SHIFT];
- printk(" pte = %08lx", page);
- }
- }
- printk("\n");
- die("Kernel access of bad area", regs, signr);
- return;
-
- /*
- * 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);
-
- /* Kernel mode? Handle exceptions or die */
- signr = SIGBUS;
- code = BUS_ADRERR;
- if (!user_mode(regs))
- goto no_context;
-
- if (exception_trace)
- printk("%s%s[%d]: bus error at %08lx pc %08lx "
- "sp %08lx ecr %lu\n",
- is_global_init(tsk) ? KERN_EMERG : KERN_INFO,
- tsk->comm, tsk->pid, address, regs->pc,
- regs->sp, ecr);
-
- _exception(SIGBUS, regs, BUS_ADRERR, address);
-}
-
-asmlinkage void do_bus_error(unsigned long addr, int write_access,
- struct pt_regs *regs)
-{
- printk(KERN_ALERT
- "Bus error at physical address 0x%08lx (%s access)\n",
- addr, write_access ? "write" : "read");
- printk(KERN_INFO "DTLB dump:\n");
- dump_dtlb();
- die("Bus Error", regs, SIGKILL);
-}
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