Merge ../linus

[linux-drm-fsl-dcu.git] / arch / i386 / mm / highmem.c

diff --git a/arch/i386/mm/highmem.c b/arch/i386/mm/highmem.c
index ba44000b9069f5376d64304fafdf43ddcd4987f7..e0fa6cb655a82574a50c3e8fc9334c2f71b9c156 100644 (file)
--- a/arch/i386/mm/highmem.c
+++ b/arch/i386/mm/highmem.c
@@ -32,47 +32,40 @@ void *kmap_atomic(struct page *page, enum km_type type)
        unsigned long vaddr;
 
        /* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
-       inc_preempt_count();
+       pagefault_disable();
        if (!PageHighMem(page))
                return page_address(page);
 
        idx = type + KM_TYPE_NR*smp_processor_id();
        vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
        if (!pte_none(*(kmap_pte-idx)))
                BUG();
-#endif
        set_pte(kmap_pte-idx, mk_pte(page, kmap_prot));
-       __flush_tlb_one(vaddr);
 
        return (void*) vaddr;
 }
 
 void kunmap_atomic(void *kvaddr, enum km_type type)
 {
-#ifdef CONFIG_DEBUG_HIGHMEM
        unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
        enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id();
 
-       if (vaddr >= PAGE_OFFSET && vaddr < (unsigned long)high_memory) {
-               dec_preempt_count();
-               preempt_check_resched();
-               return;
-       }
-
-       if (vaddr != __fix_to_virt(FIX_KMAP_BEGIN+idx))
-               BUG();
-
        /*
-        * force other mappings to Oops if they'll try to access
-        * this pte without first remap it
+        * Force other mappings to Oops if they'll try to access this pte
+        * without first remap it.  Keeping stale mappings around is a bad idea
+        * also, in case the page changes cacheability attributes or becomes
+        * a protected page in a hypervisor.
         */
-       pte_clear(&init_mm, vaddr, kmap_pte-idx);
-       __flush_tlb_one(vaddr);
+       if (vaddr == __fix_to_virt(FIX_KMAP_BEGIN+idx))
+               kpte_clear_flush(kmap_pte-idx, vaddr);
+       else {
+#ifdef CONFIG_DEBUG_HIGHMEM
+               BUG_ON(vaddr < PAGE_OFFSET);
+               BUG_ON(vaddr >= (unsigned long)high_memory);
 #endif
+       }
 
-       dec_preempt_count();
-       preempt_check_resched();
+       pagefault_enable();
 }
 
 /* This is the same as kmap_atomic() but can map memory that doesn't
@@ -83,12 +76,11 @@ void *kmap_atomic_pfn(unsigned long pfn, enum km_type type)
        enum fixed_addresses idx;
        unsigned long vaddr;
 
-       inc_preempt_count();
+       pagefault_disable();
 
        idx = type + KM_TYPE_NR*smp_processor_id();
        vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
        set_pte(kmap_pte-idx, pfn_pte(pfn, kmap_prot));
-       __flush_tlb_one(vaddr);
 
        return (void*) vaddr;
 }