1 files changed, 0 insertions, 396 deletions
diff --git a/arch/nds32/mm/fault.c b/arch/nds32/mm/fault.c
deleted file mode 100644
index 636977a1c8b9..000000000000
--- a/arch/nds32/mm/fault.c
+++ /dev/null
@@ -1,396 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-// Copyright (C) 2005-2017 Andes Technology Corporation
-
-#include <linux/extable.h>
-#include <linux/module.h>
-#include <linux/signal.h>
-#include <linux/ptrace.h>
-#include <linux/mm.h>
-#include <linux/init.h>
-#include <linux/hardirq.h>
-#include <linux/uaccess.h>
-#include <linux/perf_event.h>
-
-#include <asm/tlbflush.h>
-
-extern void __noreturn die(const char *str, struct pt_regs *regs, long err);
-
-/*
- * 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;
-
-	pr_alert("pgd = %p\n", mm->pgd);
-	pgd = pgd_offset(mm, addr);
-	pr_alert("[%08lx] *pgd=%08lx", addr, pgd_val(*pgd));
-
-	do {
-		p4d_t *p4d;
-		pud_t *pud;
-		pmd_t *pmd;
-
-		if (pgd_none(*pgd))
-			break;
-
-		if (pgd_bad(*pgd)) {
-			pr_alert("(bad)");
-			break;
-		}
-
-		p4d = p4d_offset(pgd, addr);
-		pud = pud_offset(p4d, addr);
-		pmd = pmd_offset(pud, addr);
-#if PTRS_PER_PMD != 1
-		pr_alert(", *pmd=%08lx", pmd_val(*pmd));
-#endif
-
-		if (pmd_none(*pmd))
-			break;
-
-		if (pmd_bad(*pmd)) {
-			pr_alert("(bad)");
-			break;
-		}
-
-		if (IS_ENABLED(CONFIG_HIGHMEM))
-		{
-			pte_t *pte;
-			/* We must not map this if we have highmem enabled */
-			pte = pte_offset_map(pmd, addr);
-			pr_alert(", *pte=%08lx", pte_val(*pte));
-			pte_unmap(pte);
-		}
-	} while (0);
-
-	pr_alert("\n");
-}
-
-void do_page_fault(unsigned long entry, unsigned long addr,
-		   unsigned int error_code, struct pt_regs *regs)
-{
-	struct task_struct *tsk;
-	struct mm_struct *mm;
-	struct vm_area_struct *vma;
-	int si_code;
-	vm_fault_t fault;
-	unsigned int mask = VM_ACCESS_FLAGS;
-	unsigned int flags = FAULT_FLAG_DEFAULT;
-
-	error_code = error_code & (ITYPE_mskINST | ITYPE_mskETYPE);
-	tsk = current;
-	mm = tsk->mm;
-	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.
-	 */
-	if (addr >= TASK_SIZE) {
-		if (user_mode(regs))
-			goto bad_area_nosemaphore;
-
-		if (addr >= TASK_SIZE && addr < VMALLOC_END
-		    && (entry == ENTRY_PTE_NOT_PRESENT))
-			goto vmalloc_fault;
-		else
-			goto no_context;
-	}
-
-	/* Send a signal to the task for handling the unalignment access. */
-	if (entry == ENTRY_GENERAL_EXCPETION
-	    && error_code == ETYPE_ALIGNMENT_CHECK) {
-		if (user_mode(regs))
-			goto bad_area_nosemaphore;
-		else
-			goto no_context;
-	}
-
-	/*
-	 * If we're in an interrupt or have no user
-	 * context, we must not take the fault..
-	 */
-	if (unlikely(faulthandler_disabled() || !mm))
-		goto no_context;
-
-	perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr);
-
-	/*
-	 * As per x86, we may deadlock here. However, since the kernel only
-	 * validly references user space from well defined areas of the code,
-	 * we can bug out early if this is from code which shouldn't.
-	 */
-	if (unlikely(!mmap_read_trylock(mm))) {
-		if (!user_mode(regs) &&
-		    !search_exception_tables(instruction_pointer(regs)))
-			goto no_context;
-retry:
-		mmap_read_lock(mm);
-	} else {
-		/*
-		 * The above down_read_trylock() might have succeeded in which
-		 * case, we'll have missed the might_sleep() from down_read().
-		 */
-		might_sleep();
-		if (IS_ENABLED(CONFIG_DEBUG_VM)) {
-			if (!user_mode(regs) &&
-			    !search_exception_tables(instruction_pointer(regs)))
-				goto no_context;
-		}
-	}
-
-	vma = find_vma(mm, addr);
-
-	if (unlikely(!vma))
-		goto bad_area;
-
-	if (vma->vm_start <= addr)
-		goto good_area;
-
-	if (unlikely(!(vma->vm_flags & VM_GROWSDOWN)))
-		goto bad_area;
-
-	if (unlikely(expand_stack(vma, addr)))
-		goto bad_area;
-
-	/*
-	 * Ok, we have a good vm_area for this memory access, so
-	 * we can handle it..
-	 */
-
-good_area:
-	si_code = SEGV_ACCERR;
-
-	/* first do some preliminary protection checks */
-	if (entry == ENTRY_PTE_NOT_PRESENT) {
-		if (error_code & ITYPE_mskINST)
-			mask = VM_EXEC;
-		else {
-			mask = VM_READ | VM_WRITE;
-		}
-	} else if (entry == ENTRY_TLB_MISC) {
-		switch (error_code & ITYPE_mskETYPE) {
-		case RD_PROT:
-			mask = VM_READ;
-			break;
-		case WRT_PROT:
-			mask = VM_WRITE;
-			flags |= FAULT_FLAG_WRITE;
-			break;
-		case NOEXEC:
-			mask = VM_EXEC;
-			break;
-		case PAGE_MODIFY:
-			mask = VM_WRITE;
-			flags |= FAULT_FLAG_WRITE;
-			break;
-		case ACC_BIT:
-			BUG();
-		default:
-			break;
-		}
-
-	}
-	if (!(vma->vm_flags & 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, addr, flags, regs);
-
-	/*
-	 * If we need to retry but a fatal signal is pending, handle the
-	 * signal first. We do not need to release the mmap_lock because it
-	 * would already be released in __lock_page_or_retry in mm/filemap.c.
-	 */
-	if (fault_signal_pending(fault, regs)) {
-		if (!user_mode(regs))
-			goto no_context;
-		return;
-	}
-
-	if (unlikely(fault & VM_FAULT_ERROR)) {
-		if (fault & VM_FAULT_OOM)
-			goto out_of_memory;
-		else if (fault & VM_FAULT_SIGBUS)
-			goto do_sigbus;
-		else
-			goto bad_area;
-	}
-
-	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;
-
-	/*
-	 * 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:
-	mmap_read_unlock(mm);
-
-bad_area_nosemaphore:
-
-	/* User mode accesses just cause a SIGSEGV */
-
-	if (user_mode(regs)) {
-		tsk->thread.address = addr;
-		tsk->thread.error_code = error_code;
-		tsk->thread.trap_no = entry;
-		force_sig_fault(SIGSEGV, si_code, (void __user *)addr);
-		return;
-	}
-
-no_context:
-
-	/* Are we prepared to handle this kernel fault?
-	 *
-	 * (The kernel has valid exception-points in the source
-	 *  when it acesses user-memory. When it fails in one
-	 *  of those points, we find it in a table and do a jump
-	 *  to some fixup code that loads an appropriate error
-	 *  code)
-	 */
-
-	{
-		const struct exception_table_entry *entry;
-
-		if ((entry =
-		     search_exception_tables(instruction_pointer(regs))) !=
-		    NULL) {
-			/* Adjust the instruction pointer in the stackframe */
-			instruction_pointer(regs) = entry->fixup;
-			return;
-		}
-	}
-
-	/*
-	 * Oops. The kernel tried to access some bad page. We'll have to
-	 * terminate things with extreme prejudice.
-	 */
-
-	bust_spinlocks(1);
-	pr_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, error_code);
-
-	/*
-	 * 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:
-	mmap_read_unlock(mm);
-	if (!user_mode(regs))
-		goto no_context;
-	pagefault_out_of_memory();
-	return;
-
-do_sigbus:
-	mmap_read_unlock(mm);
-
-	/* Kernel mode? Handle exceptions or die */
-	if (!user_mode(regs))
-		goto no_context;
-
-	/*
-	 * Send a sigbus
-	 */
-	tsk->thread.address = addr;
-	tsk->thread.error_code = error_code;
-	tsk->thread.trap_no = entry;
-	force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)addr);
-
-	return;
-
-vmalloc_fault:
-	{
-		/*
-		 * Synchronize this task's top level page-table
-		 * with the 'reference' page table.
-		 *
-		 * Use current_pgd instead of tsk->active_mm->pgd
-		 * since the latter might be unavailable if this
-		 * code is executed in a misfortunately run irq
-		 * (like inside schedule() between switch_mm and
-		 *  switch_to...).
-		 */
-
-		unsigned int index = pgd_index(addr);
-		pgd_t *pgd, *pgd_k;
-		p4d_t *p4d, *p4d_k;
-		pud_t *pud, *pud_k;
-		pmd_t *pmd, *pmd_k;
-		pte_t *pte_k;
-
-		pgd = (pgd_t *) __va(__nds32__mfsr(NDS32_SR_L1_PPTB)) + index;
-		pgd_k = init_mm.pgd + index;
-
-		if (!pgd_present(*pgd_k))
-			goto no_context;
-
-		p4d = p4d_offset(pgd, addr);
-		p4d_k = p4d_offset(pgd_k, addr);
-		if (!p4d_present(*p4d_k))
-			goto no_context;
-
-		pud = pud_offset(p4d, addr);
-		pud_k = pud_offset(p4d_k, addr);
-		if (!pud_present(*pud_k))
-			goto no_context;
-
-		pmd = pmd_offset(pud, addr);
-		pmd_k = pmd_offset(pud_k, addr);
-		if (!pmd_present(*pmd_k))
-			goto no_context;
-
-		if (!pmd_present(*pmd))
-			set_pmd(pmd, *pmd_k);
-		else
-			BUG_ON(pmd_page(*pmd) != pmd_page(*pmd_k));
-
-		/*
-		 * Since the vmalloc area is global, we don't
-		 * need to copy individual PTE's, it is enough to
-		 * copy the pgd pointer into the pte page of the
-		 * root task. If that is there, we'll find our pte if
-		 * it exists.
-		 */
-
-		/* Make sure the actual PTE exists as well to
-		 * catch kernel vmalloc-area accesses to non-mapped
-		 * addres. If we don't do this, this will just
-		 * silently loop forever.
-		 */
-
-		pte_k = pte_offset_kernel(pmd_k, addr);
-		if (!pte_present(*pte_k))
-			goto no_context;
-
-		return;
-	}
-}