sh64: Port OOM changes to do_page_fault

Reflect the sh32 OOM changes for the sh64 page fault handler, too.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

diff --git a/arch/sh/mm/tlbflush_64.c b/arch/sh/mm/tlbflush_64.c
index 11c5a18f10ed9655c5fbc7acc6e5202b28b05e93..70b3c271aa9fc42c2ab24aa6adb91b872bc9847a 100644 (file)
--- a/arch/sh/mm/tlbflush_64.c
+++ b/arch/sh/mm/tlbflush_64.c
@@ -3,7 +3,7 @@
  *
  * Copyright (C) 2000, 2001  Paolo Alberelli
  * Copyright (C) 2003  Richard Curnow (/proc/tlb, bug fixes)
- * Copyright (C) 2003 - 2009 Paul Mundt
+ * Copyright (C) 2003 - 2012 Paul Mundt
  *
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
@@ -95,6 +95,8 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long writeaccess,
        struct mm_struct *mm;
        struct vm_area_struct * vma;
        const struct exception_table_entry *fixup;
+       unsigned int flags = (FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE |
+                             (writeaccess ? FAULT_FLAG_WRITE : 0));
        pte_t *pte;
        int fault;
 
@@ -124,6 +126,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long writeaccess,
        if (in_atomic() || !mm)
                goto no_context;
 
+retry:
        /* TLB misses upon some cache flushes get done under cli() */
        down_read(&mm->mmap_sem);
 
@@ -188,7 +191,11 @@ good_area:
         * make sure we exit gracefully rather than endlessly redo
         * the fault.
         */
-       fault = handle_mm_fault(mm, vma, address, writeaccess ? FAULT_FLAG_WRITE : 0);
+       fault = handle_mm_fault(mm, 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;
@@ -197,14 +204,27 @@ good_area:
                BUG();
        }
 
-       if (fault & VM_FAULT_MAJOR) {
-               tsk->maj_flt++;
-               perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1,
-                                    regs, address);
-       } else {
-               tsk->min_flt++;
-               perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1,
-                                    regs, address);
+       if (flags & FAULT_FLAG_ALLOW_RETRY) {
+               if (fault & VM_FAULT_MAJOR) {
+                       tsk->maj_flt++;
+                       perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1,
+                                     regs, address);
+               } else {
+                       tsk->min_flt++;
+                       perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1,
+                                     regs, address);
+               }
+
+               if (fault & VM_FAULT_RETRY) {
+                       flags &= ~FAULT_FLAG_ALLOW_RETRY;
+
+                       /*
+                        * 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;
+               }
        }
 
        /* If we get here, the page fault has been handled.  Do the TLB refill