diff options
Diffstat (limited to 'arch/ia64/mm/fault.c')
-rw-r--r-- | arch/ia64/mm/fault.c | 251 |
1 files changed, 0 insertions, 251 deletions
diff --git a/arch/ia64/mm/fault.c b/arch/ia64/mm/fault.c deleted file mode 100644 index 5458b52b40..0000000000 --- a/arch/ia64/mm/fault.c +++ /dev/null @@ -1,251 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * MMU fault handling support. - * - * Copyright (C) 1998-2002 Hewlett-Packard Co - * David Mosberger-Tang <davidm@hpl.hp.com> - */ -#include <linux/sched/signal.h> -#include <linux/kernel.h> -#include <linux/mm.h> -#include <linux/extable.h> -#include <linux/interrupt.h> -#include <linux/kprobes.h> -#include <linux/kdebug.h> -#include <linux/prefetch.h> -#include <linux/uaccess.h> -#include <linux/perf_event.h> - -#include <asm/processor.h> -#include <asm/exception.h> - -extern int die(char *, struct pt_regs *, long); - -/* - * 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; - p4d_t *p4d; - pud_t *pud; - pmd_t *pmd; - pte_t *ptep, pte; - - pgd = pgd_offset_k(address); - if (pgd_none(*pgd) || pgd_bad(*pgd)) - return 0; - - p4d = p4d_offset(pgd, address); - if (p4d_none(*p4d) || p4d_bad(*p4d)) - return 0; - - pud = pud_offset(p4d, 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); -} - -# define VM_READ_BIT 0 -# define VM_WRITE_BIT 1 -# define VM_EXEC_BIT 2 - -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; - unsigned long mask; - vm_fault_t fault; - unsigned int flags = FAULT_FLAG_DEFAULT; - - mask = ((((isr >> IA64_ISR_X_BIT) & 1UL) << VM_EXEC_BIT) - | (((isr >> IA64_ISR_W_BIT) & 1UL) << VM_WRITE_BIT)); - - /* mmap_lock is performance critical.... */ - prefetchw(&mm->mmap_lock); - - /* - * If we're in an interrupt or have no user context, we must not take the fault.. - */ - if (faulthandler_disabled() || !mm) - goto no_context; - - /* - * This is to handle the kprobes on user space access instructions - */ - if (kprobe_page_fault(regs, TRAP_BRKPT)) - return; - - if (user_mode(regs)) - flags |= FAULT_FLAG_USER; - if (mask & VM_WRITE) - flags |= FAULT_FLAG_WRITE; - - perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); -retry: - mmap_read_lock(mm); - - 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) ) { - vma = expand_stack(mm, address); - if (!vma) - goto bad_area_nosemaphore; - } - - code = SEGV_ACCERR; - - /* OK, we've got a good vm_area for this memory area. Check the access permissions: */ - -# 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; - - 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(vma, address, flags, regs); - - if (fault_signal_pending(fault, regs)) { - if (!user_mode(regs)) - goto no_context; - return; - } - - /* The fault is fully completed (including releasing mmap lock) */ - if (fault & VM_FAULT_COMPLETED) - return; - - 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_SIGSEGV) { - goto bad_area; - } else if (fault & VM_FAULT_SIGBUS) { - signal = SIGBUS; - goto bad_area; - } - BUG(); - } - - if (fault & VM_FAULT_RETRY) { - flags |= FAULT_FLAG_TRIED; - - /* No need to mmap_read_unlock(mm) as we would - * have already released it in __lock_page_or_retry - * in mm/filemap.c. - */ - - goto retry; - } - - mmap_read_unlock(mm); - return; - - bad_area: - mmap_read_unlock(mm); - bad_area_nosemaphore: - 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)) { - force_sig_fault(signal, code, (void __user *) address, - 0, __ISR_VALID, isr); - 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) - make_task_dead(SIGKILL); - return; - - out_of_memory: - mmap_read_unlock(mm); - if (!user_mode(regs)) - goto no_context; - pagefault_out_of_memory(); -} |