mm: export symbol dependencies of is_zero_pfn()

[firefly-linux-kernel-4.4.55.git] / mm / memory.c

diff --git a/mm/memory.c b/mm/memory.c
index 61a262b08e53efa2f69c1387e488bea6f87bb0f9..20bb9e9017817ecb29ff492f723d868c58827ed2 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -118,6 +118,8 @@ __setup("norandmaps", disable_randmaps);
 unsigned long zero_pfn __read_mostly;
 unsigned long highest_memmap_pfn __read_mostly;
 
+EXPORT_SYMBOL(zero_pfn);
+
 /*
  * CONFIG_MMU architectures set up ZERO_PAGE in their paging_init()
  */
@@ -211,14 +213,15 @@ static int tlb_next_batch(struct mmu_gather *tlb)
  *     tear-down from @mm. The @fullmm argument is used when @mm is without
  *     users and we're going to destroy the full address space (exit/execve).
  */
-void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, bool fullmm)
+void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, unsigned long start, unsigned long end)
 {
        tlb->mm = mm;
 
-       tlb->fullmm     = fullmm;
+       /* Is it from 0 to ~0? */
+       tlb->fullmm     = !(start | (end+1));
        tlb->need_flush_all = 0;
-       tlb->start      = -1UL;
-       tlb->end        = 0;
+       tlb->start      = start;
+       tlb->end        = end;
        tlb->need_flush = 0;
        tlb->local.next = NULL;
        tlb->local.nr   = 0;
@@ -258,8 +261,6 @@ void tlb_finish_mmu(struct mmu_gather *tlb, unsigned long start, unsigned long e
 {
        struct mmu_gather_batch *batch, *next;
 
-       tlb->start = start;
-       tlb->end   = end;
        tlb_flush_mmu(tlb);
 
        /* keep the page table cache within bounds */
@@ -1203,13 +1204,23 @@ again:
         * and page-free while holding it.
         */
        if (force_flush) {
+               unsigned long old_end;
+
                force_flush = 0;
 
-#ifdef HAVE_GENERIC_MMU_GATHER
-               tlb->start = addr;
-               tlb->end = end;
-#endif
+               /*
+                * Flush the TLB just for the previous segment,
+                * then update the range to be the remaining
+                * TLB range.
+                */
+               old_end = tlb->end;
+               tlb->end = addr;
+
                tlb_flush_mmu(tlb);
+
+               tlb->start = addr;
+               tlb->end = old_end;
+
                if (addr != end)
                        goto again;
        }
@@ -1396,7 +1407,7 @@ void zap_page_range(struct vm_area_struct *vma, unsigned long start,
        unsigned long end = start + size;
 
        lru_add_drain();
-       tlb_gather_mmu(&tlb, mm, 0);
+       tlb_gather_mmu(&tlb, mm, start, end);
        update_hiwater_rss(mm);
        mmu_notifier_invalidate_range_start(mm, start, end);
        for ( ; vma && vma->vm_start < end; vma = vma->vm_next)
@@ -1422,7 +1433,7 @@ static void zap_page_range_single(struct vm_area_struct *vma, unsigned long addr
        unsigned long end = address + size;
 
        lru_add_drain();
-       tlb_gather_mmu(&tlb, mm, 0);
+       tlb_gather_mmu(&tlb, mm, address, end);
        update_hiwater_rss(mm);
        mmu_notifier_invalidate_range_start(mm, address, end);
        unmap_single_vma(&tlb, vma, address, end, details);