diff options
Diffstat (limited to 'ANDROID_3.4.5/arch/ia64/mm/fault.c')
-rw-r--r-- | ANDROID_3.4.5/arch/ia64/mm/fault.c | 281 |
1 files changed, 0 insertions, 281 deletions
diff --git a/ANDROID_3.4.5/arch/ia64/mm/fault.c b/ANDROID_3.4.5/arch/ia64/mm/fault.c deleted file mode 100644 index 02d29c2a..00000000 --- a/ANDROID_3.4.5/arch/ia64/mm/fault.c +++ /dev/null @@ -1,281 +0,0 @@ -/* - * MMU fault handling support. - * - * Copyright (C) 1998-2002 Hewlett-Packard Co - * David Mosberger-Tang <davidm@hpl.hp.com> - */ -#include <linux/sched.h> -#include <linux/kernel.h> -#include <linux/mm.h> -#include <linux/interrupt.h> -#include <linux/kprobes.h> -#include <linux/kdebug.h> -#include <linux/prefetch.h> - -#include <asm/pgtable.h> -#include <asm/processor.h> -#include <asm/uaccess.h> - -extern int die(char *, struct pt_regs *, long); - -#ifdef CONFIG_KPROBES -static inline int notify_page_fault(struct pt_regs *regs, int trap) -{ - int ret = 0; - - if (!user_mode(regs)) { - /* kprobe_running() needs smp_processor_id() */ - preempt_disable(); - if (kprobe_running() && kprobe_fault_handler(regs, trap)) - ret = 1; - preempt_enable(); - } - - return ret; -} -#else -static inline int notify_page_fault(struct pt_regs *regs, int trap) -{ - return 0; -} -#endif - -/* - * Return TRUE if ADDRESS points at a page in the kernel's mapped segment - * (inside region 5, on ia64) and that page is present. - */ -static int -mapped_kernel_page_is_present (unsigned long address) -{ - pgd_t *pgd; - pud_t *pud; - pmd_t *pmd; - pte_t *ptep, pte; - - pgd = pgd_offset_k(address); - if (pgd_none(*pgd) || pgd_bad(*pgd)) - return 0; - - pud = pud_offset(pgd, address); - if (pud_none(*pud) || pud_bad(*pud)) - return 0; - - pmd = pmd_offset(pud, address); - if (pmd_none(*pmd) || pmd_bad(*pmd)) - return 0; - - ptep = pte_offset_kernel(pmd, address); - if (!ptep) - return 0; - - pte = *ptep; - return pte_present(pte); -} - -void __kprobes -ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *regs) -{ - int signal = SIGSEGV, code = SEGV_MAPERR; - struct vm_area_struct *vma, *prev_vma; - struct mm_struct *mm = current->mm; - struct siginfo si; - unsigned long mask; - int fault; - - /* mmap_sem is performance critical.... */ - prefetchw(&mm->mmap_sem); - - /* - * If we're in an interrupt or have no user context, we must not take the fault.. - */ - if (in_atomic() || !mm) - goto no_context; - -#ifdef CONFIG_VIRTUAL_MEM_MAP - /* - * If fault is in region 5 and we are in the kernel, we may already - * have the mmap_sem (pfn_valid macro is called during mmap). There - * is no vma for region 5 addr's anyway, so skip getting the semaphore - * and go directly to the exception handling code. - */ - - if ((REGION_NUMBER(address) == 5) && !user_mode(regs)) - goto bad_area_no_up; -#endif - - /* - * This is to handle the kprobes on user space access instructions - */ - if (notify_page_fault(regs, TRAP_BRKPT)) - return; - - down_read(&mm->mmap_sem); - - vma = find_vma_prev(mm, address, &prev_vma); - if (!vma && !prev_vma ) - goto bad_area; - - /* - * find_vma_prev() returns vma such that address < vma->vm_end or NULL - * - * May find no vma, but could be that the last vm area is the - * register backing store that needs to expand upwards, in - * this case vma will be null, but prev_vma will ne non-null - */ - if (( !vma && prev_vma ) || (address < vma->vm_start) ) - goto check_expansion; - - good_area: - code = SEGV_ACCERR; - - /* OK, we've got a good vm_area for this memory area. Check the access permissions: */ - -# define VM_READ_BIT 0 -# define VM_WRITE_BIT 1 -# define VM_EXEC_BIT 2 - -# if (((1 << VM_READ_BIT) != VM_READ || (1 << VM_WRITE_BIT) != VM_WRITE) \ - || (1 << VM_EXEC_BIT) != VM_EXEC) -# error File is out of sync with <linux/mm.h>. Please update. -# endif - - if (((isr >> IA64_ISR_R_BIT) & 1UL) && (!(vma->vm_flags & (VM_READ | VM_WRITE)))) - goto bad_area; - - mask = ( (((isr >> IA64_ISR_X_BIT) & 1UL) << VM_EXEC_BIT) - | (((isr >> IA64_ISR_W_BIT) & 1UL) << VM_WRITE_BIT)); - - if ((vma->vm_flags & mask) != mask) - 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, (mask & VM_WRITE) ? FAULT_FLAG_WRITE : 0); - if (unlikely(fault & VM_FAULT_ERROR)) { - /* - * We ran out of memory, or some other thing happened - * to us that made us unable to handle the page fault - * gracefully. - */ - if (fault & VM_FAULT_OOM) { - goto out_of_memory; - } else if (fault & VM_FAULT_SIGBUS) { - signal = SIGBUS; - goto bad_area; - } - BUG(); - } - if (fault & VM_FAULT_MAJOR) - current->maj_flt++; - else - current->min_flt++; - up_read(&mm->mmap_sem); - return; - - check_expansion: - if (!(prev_vma && (prev_vma->vm_flags & VM_GROWSUP) && (address == prev_vma->vm_end))) { - if (!vma) - goto bad_area; - if (!(vma->vm_flags & VM_GROWSDOWN)) - goto bad_area; - if (REGION_NUMBER(address) != REGION_NUMBER(vma->vm_start) - || REGION_OFFSET(address) >= RGN_MAP_LIMIT) - goto bad_area; - if (expand_stack(vma, address)) - goto bad_area; - } else { - vma = prev_vma; - if (REGION_NUMBER(address) != REGION_NUMBER(vma->vm_start) - || REGION_OFFSET(address) >= RGN_MAP_LIMIT) - goto bad_area; - /* - * Since the register backing store is accessed sequentially, - * we disallow growing it by more than a page at a time. - */ - if (address > vma->vm_end + PAGE_SIZE - sizeof(long)) - goto bad_area; - if (expand_upwards(vma, address)) - goto bad_area; - } - goto good_area; - - bad_area: - up_read(&mm->mmap_sem); -#ifdef CONFIG_VIRTUAL_MEM_MAP - bad_area_no_up: -#endif - if ((isr & IA64_ISR_SP) - || ((isr & IA64_ISR_NA) && (isr & IA64_ISR_CODE_MASK) == IA64_ISR_CODE_LFETCH)) - { - /* - * This fault was due to a speculative load or lfetch.fault, set the "ed" - * bit in the psr to ensure forward progress. (Target register will get a - * NaT for ld.s, lfetch will be canceled.) - */ - ia64_psr(regs)->ed = 1; - return; - } - if (user_mode(regs)) { - si.si_signo = signal; - si.si_errno = 0; - si.si_code = code; - si.si_addr = (void __user *) address; - si.si_isr = isr; - si.si_flags = __ISR_VALID; - force_sig_info(signal, &si, current); - return; - } - - no_context: - if ((isr & IA64_ISR_SP) - || ((isr & IA64_ISR_NA) && (isr & IA64_ISR_CODE_MASK) == IA64_ISR_CODE_LFETCH)) - { - /* - * This fault was due to a speculative load or lfetch.fault, set the "ed" - * bit in the psr to ensure forward progress. (Target register will get a - * NaT for ld.s, lfetch will be canceled.) - */ - ia64_psr(regs)->ed = 1; - return; - } - - /* - * Since we have no vma's for region 5, we might get here even if the address is - * valid, due to the VHPT walker inserting a non present translation that becomes - * stale. If that happens, the non present fault handler already purged the stale - * translation, which fixed the problem. So, we check to see if the translation is - * valid, and return if it is. - */ - if (REGION_NUMBER(address) == 5 && mapped_kernel_page_is_present(address)) - return; - - if (ia64_done_with_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 (address %016lx)\n", address); - else - printk(KERN_ALERT "Unable to handle kernel paging request at " - "virtual address %016lx\n", address); - if (die("Oops", regs, isr)) - regs = NULL; - bust_spinlocks(0); - if (regs) - do_exit(SIGKILL); - return; - - out_of_memory: - up_read(&mm->mmap_sem); - if (!user_mode(regs)) - goto no_context; - pagefault_out_of_memory(); -} |