1 files changed, 39 insertions, 22 deletions

diff --git a/include/linux/highmem.h b/include/linux/highmem.h
index 283cd47bb34c..8a85ec109a3a 100644
--- a/include/linux/highmem.h
+++ b/include/linux/highmem.h
@@ -28,18 +28,6 @@ static inline void invalidate_kernel_vmap_range(void *vaddr, int size)
 
 #include <asm/kmap_types.h>
 
-#ifdef CONFIG_DEBUG_HIGHMEM
-
-void debug_kmap_atomic(enum km_type type);
-
-#else
-
-static inline void debug_kmap_atomic(enum km_type type)
-{
-}
-
-#endif
-
 #ifdef CONFIG_HIGHMEM
 #include <asm/highmem.h>
 
@@ -49,6 +37,27 @@ extern unsigned long totalhigh_pages;
 
 void kmap_flush_unused(void);
 
+DECLARE_PER_CPU(int, __kmap_atomic_idx);
+
+static inline int kmap_atomic_idx_push(void)
+{
+	int idx = __get_cpu_var(__kmap_atomic_idx)++;
+#ifdef CONFIG_DEBUG_HIGHMEM
+	WARN_ON_ONCE(in_irq() && !irqs_disabled());
+	BUG_ON(idx > KM_TYPE_NR);
+#endif
+	return idx;
+}
+
+static inline int kmap_atomic_idx_pop(void)
+{
+	int idx = --__get_cpu_var(__kmap_atomic_idx);
+#ifdef CONFIG_DEBUG_HIGHMEM
+	BUG_ON(idx < 0);
+#endif
+	return idx;
+}
+
 #else /* CONFIG_HIGHMEM */
 
 static inline unsigned int nr_free_highpages(void) { return 0; }
@@ -66,19 +75,19 @@ static inline void kunmap(struct page *page)
 {
 }
 
-static inline void *kmap_atomic(struct page *page, enum km_type idx)
+static inline void *__kmap_atomic(struct page *page)
 {
 	pagefault_disable();
 	return page_address(page);
 }
-#define kmap_atomic_prot(page, idx, prot)	kmap_atomic(page, idx)
+#define kmap_atomic_prot(page, prot)	__kmap_atomic(page)
 
-static inline void kunmap_atomic_notypecheck(void *addr, enum km_type idx)
+static inline void __kunmap_atomic(void *addr)
 {
 	pagefault_enable();
 }
 
-#define kmap_atomic_pfn(pfn, idx)	kmap_atomic(pfn_to_page(pfn), (idx))
+#define kmap_atomic_pfn(pfn)	kmap_atomic(pfn_to_page(pfn))
 #define kmap_atomic_to_page(ptr)	virt_to_page(ptr)
 
 #define kmap_flush_unused()	do {} while(0)
@@ -86,12 +95,20 @@ static inline void kunmap_atomic_notypecheck(void *addr, enum km_type idx)
 
 #endif /* CONFIG_HIGHMEM */
 
-/* Prevent people trying to call kunmap_atomic() as if it were kunmap() */
-/* kunmap_atomic() should get the return value of kmap_atomic, not the page. */
-#define kunmap_atomic(addr, idx) do { \
-		BUILD_BUG_ON(__same_type((addr), struct page *)); \
-		kunmap_atomic_notypecheck((addr), (idx)); \
-	} while (0)
+/*
+ * Make both: kmap_atomic(page, idx) and kmap_atomic(page) work.
+ */
+#define kmap_atomic(page, args...) __kmap_atomic(page)
+
+/*
+ * Prevent people trying to call kunmap_atomic() as if it were kunmap()
+ * kunmap_atomic() should get the return value of kmap_atomic, not the page.
+ */
+#define kunmap_atomic(addr, args...)				\
+do {								\
+	BUILD_BUG_ON(__same_type((addr), struct page *));	\
+	__kunmap_atomic(addr);					\
+} while (0)
 
 /* when CONFIG_HIGHMEM is not set these will be plain clear/copy_page */
 #ifndef clear_user_highpage