mm: stack based kmap_atomic()

Keep the current interface but ignore the KM_type and use a stack based
approach.

The advantage is that we get rid of crappy code like:

	#define __KM_PTE			\
		(in_nmi() ? KM_NMI_PTE : 	\
		 in_irq() ? KM_IRQ_PTE :	\
		 KM_PTE0)

and in general can stop worrying about what context we're in and what kmap
slots might be appropriate for that.

The downside is that FRV kmap_atomic() gets more expensive.

For now we use a CPP trick suggested by Andrew:

  #define kmap_atomic(page, args...) __kmap_atomic(page)

to avoid having to touch all kmap_atomic() users in a single patch.

[ not compiled on:
  - mn10300: the arch doesn't actually build with highmem to begin with ]

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix up drivers/gpu/drm/i915/intel_overlay.c]
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Miller <davem@davemloft.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

28 files changed, 367 insertions, 372 deletions

diff --git a/arch/arm/include/asm/highmem.h b/arch/arm/include/asm/highmem.h
index 5aff58126602..1fc684e70ab6 100644
--- a/arch/arm/include/asm/highmem.h
+++ b/arch/arm/include/asm/highmem.h
@@ -35,9 +35,9 @@ extern void kunmap_high_l1_vipt(struct page *page, pte_t saved_pte);
 #ifdef CONFIG_HIGHMEM
 extern void *kmap(struct page *page);
 extern void kunmap(struct page *page);
-extern void *kmap_atomic(struct page *page, enum km_type type);
-extern void kunmap_atomic_notypecheck(void *kvaddr, enum km_type type);
-extern void *kmap_atomic_pfn(unsigned long pfn, enum km_type type);
+extern void *__kmap_atomic(struct page *page);
+extern void __kunmap_atomic(void *kvaddr);
+extern void *kmap_atomic_pfn(unsigned long pfn);
 extern struct page *kmap_atomic_to_page(const void *ptr);
 #endif
 
diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c
index 1fbdb55bfd1b..c00f119babbf 100644
--- a/arch/arm/mm/highmem.c
+++ b/arch/arm/mm/highmem.c
@@ -36,18 +36,17 @@ void kunmap(struct page *page)
 }
 EXPORT_SYMBOL(kunmap);
 
-void *kmap_atomic(struct page *page, enum km_type type)
+void *__kmap_atomic(struct page *page)
 {
         unsigned int idx;
         unsigned long vaddr;
         void *kmap;
+        int type;
 
         pagefault_disable();
         if (!PageHighMem(page))
                 return page_address(page);
 
-        debug_kmap_atomic(type);
-
 #ifdef CONFIG_DEBUG_HIGHMEM
         /*
          * There is no cache coherency issue when non VIVT, so force the
@@ -61,6 +60,8 @@ void *kmap_atomic(struct page *page, enum km_type type)
         if (kmap)
                 return kmap;
 
+        type = kmap_atomic_idx_push();
+
         idx = type + KM_TYPE_NR * smp_processor_id();
         vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
 #ifdef CONFIG_DEBUG_HIGHMEM
@@ -80,14 +81,17 @@ void *kmap_atomic(struct page *page, enum km_type type)
 
         return (void *)vaddr;
 }
-EXPORT_SYMBOL(kmap_atomic);
+EXPORT_SYMBOL(__kmap_atomic);
 
-void kunmap_atomic_notypecheck(void *kvaddr, enum km_type type)
+void __kunmap_atomic(void *kvaddr)
 {
         unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-        unsigned int idx = type + KM_TYPE_NR * smp_processor_id();
+        int idx, type;
 
         if (kvaddr >= (void *)FIXADDR_START) {
+                type = kmap_atomic_idx_pop();
+                idx = type + KM_TYPE_NR * smp_processor_id();
+
                 if (cache_is_vivt())
                         __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);
 #ifdef CONFIG_DEBUG_HIGHMEM
@@ -103,15 +107,16 @@ void kunmap_atomic_notypecheck(void *kvaddr, enum km_type type)
         }
         pagefault_enable();
 }
-EXPORT_SYMBOL(kunmap_atomic_notypecheck);
+EXPORT_SYMBOL(__kunmap_atomic);
 
-void *kmap_atomic_pfn(unsigned long pfn, enum km_type type)
+void *kmap_atomic_pfn(unsigned long pfn)
 {
-        unsigned int idx;
         unsigned long vaddr;
+        int idx, type;
 
         pagefault_disable();
 
+        type = kmap_atomic_idx_push();
         idx = type + KM_TYPE_NR * smp_processor_id();
         vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
 #ifdef CONFIG_DEBUG_HIGHMEM
diff --git a/arch/frv/include/asm/highmem.h b/arch/frv/include/asm/highmem.h
index cb4c317eaecc..a8d6565d415d 100644
--- a/arch/frv/include/asm/highmem.h
+++ b/arch/frv/include/asm/highmem.h
@@ -112,12 +112,11 @@ extern struct page *kmap_atomic_to_page(void *ptr);
         (void *) damlr;                                                                           \
 })
 
-static inline void *kmap_atomic(struct page *page, enum km_type type)
+static inline void *kmap_atomic_primary(struct page *page, enum km_type type)
 {
         unsigned long paddr;
 
         pagefault_disable();
-        debug_kmap_atomic(type);
         paddr = page_to_phys(page);
 
         switch (type) {
@@ -125,14 +124,6 @@ static inline void *kmap_atomic(struct page *page, enum km_type type)
         case 1:         return __kmap_atomic_primary(1, paddr, 3);
         case 2:         return __kmap_atomic_primary(2, paddr, 4);
         case 3:         return __kmap_atomic_primary(3, paddr, 5);
-        case 4:         return __kmap_atomic_primary(4, paddr, 6);
-        case 5:         return __kmap_atomic_primary(5, paddr, 7);
-        case 6:         return __kmap_atomic_primary(6, paddr, 8);
-        case 7:         return __kmap_atomic_primary(7, paddr, 9);
-        case 8:         return __kmap_atomic_primary(8, paddr, 10);
-
-        case 9 ... 9 + NR_TLB_LINES - 1:
-                return __kmap_atomic_secondary(type - 9, paddr);
 
         default:
                 BUG();
@@ -152,22 +143,13 @@ do {									\
         asm volatile("tlbpr %0,gr0,#4,#1" : : "r"(vaddr) : "memory");   \
 } while(0)
 
-static inline void kunmap_atomic_notypecheck(void *kvaddr, enum km_type type)
+static inline void kunmap_atomic_primary(void *kvaddr, enum km_type type)
 {
         switch (type) {
         case 0:         __kunmap_atomic_primary(0, 2);  break;
         case 1:         __kunmap_atomic_primary(1, 3);  break;
         case 2:         __kunmap_atomic_primary(2, 4);  break;
         case 3:         __kunmap_atomic_primary(3, 5);  break;
-        case 4:         __kunmap_atomic_primary(4, 6);  break;
-        case 5:         __kunmap_atomic_primary(5, 7);  break;
-        case 6:         __kunmap_atomic_primary(6, 8);  break;
-        case 7:         __kunmap_atomic_primary(7, 9);  break;
-        case 8:         __kunmap_atomic_primary(8, 10); break;
-
-        case 9 ... 9 + NR_TLB_LINES - 1:
-                __kunmap_atomic_secondary(type - 9, kvaddr);
-                break;
 
         default:
                 BUG();
@@ -175,6 +157,9 @@ static inline void kunmap_atomic_notypecheck(void *kvaddr, enum km_type type)
         pagefault_enable();
 }
 
+void *__kmap_atomic(struct page *page);
+void __kunmap_atomic(void *kvaddr);
+
 #endif /* !__ASSEMBLY__ */
 
 #endif /* __KERNEL__ */
diff --git a/arch/frv/mb93090-mb00/pci-dma.c b/arch/frv/mb93090-mb00/pci-dma.c
index 85d110b71cf7..41098a3803a2 100644
--- a/arch/frv/mb93090-mb00/pci-dma.c
+++ b/arch/frv/mb93090-mb00/pci-dma.c
@@ -61,14 +61,14 @@ int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
         dampr2 = __get_DAMPR(2);
 
         for (i = 0; i < nents; i++) {
-                vaddr = kmap_atomic(sg_page(&sg[i]), __KM_CACHE);
+                vaddr = kmap_atomic_primary(sg_page(&sg[i]), __KM_CACHE);
 
                 frv_dcache_writeback((unsigned long) vaddr,
                                      (unsigned long) vaddr + PAGE_SIZE);
 
         }
 
-        kunmap_atomic(vaddr, __KM_CACHE);
+        kunmap_atomic_primary(vaddr, __KM_CACHE);
         if (dampr2) {
                 __set_DAMPR(2, dampr2);
                 __set_IAMPR(2, dampr2);
diff --git a/arch/frv/mm/cache-page.c b/arch/frv/mm/cache-page.c
index 0261cbe153b5..b24ade27a0f0 100644
--- a/arch/frv/mm/cache-page.c
+++ b/arch/frv/mm/cache-page.c
@@ -26,11 +26,11 @@ void flush_dcache_page(struct page *page)
 
         dampr2 = __get_DAMPR(2);
 
-        vaddr = kmap_atomic(page, __KM_CACHE);
+        vaddr = kmap_atomic_primary(page, __KM_CACHE);
 
         frv_dcache_writeback((unsigned long) vaddr, (unsigned long) vaddr + PAGE_SIZE);
 
-        kunmap_atomic(vaddr, __KM_CACHE);
+        kunmap_atomic_primary(vaddr, __KM_CACHE);
 
         if (dampr2) {
                 __set_DAMPR(2, dampr2);
@@ -54,12 +54,12 @@ void flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
 
         dampr2 = __get_DAMPR(2);
 
-        vaddr = kmap_atomic(page, __KM_CACHE);
+        vaddr = kmap_atomic_primary(page, __KM_CACHE);
 
         start = (start & ~PAGE_MASK) | (unsigned long) vaddr;
         frv_cache_wback_inv(start, start + len);
 
-        kunmap_atomic(vaddr, __KM_CACHE);
+        kunmap_atomic_primary(vaddr, __KM_CACHE);
 
         if (dampr2) {
                 __set_DAMPR(2, dampr2);
diff --git a/arch/frv/mm/highmem.c b/arch/frv/mm/highmem.c
index eadd07658075..61088dcc1594 100644
--- a/arch/frv/mm/highmem.c
+++ b/arch/frv/mm/highmem.c
@@ -36,3 +36,53 @@ struct page *kmap_atomic_to_page(void *ptr)
 {
         return virt_to_page(ptr);
 }
+
+void *__kmap_atomic(struct page *page)
+{
+        unsigned long paddr;
+        int type;
+
+        pagefault_disable();
+        type = kmap_atomic_idx_push();
+        paddr = page_to_phys(page);
+
+        switch (type) {
+        /*
+         * The first 4 primary maps are reserved for architecture code
+         */
+        case 0:         return __kmap_atomic_primary(4, paddr, 6);
+        case 1:         return __kmap_atomic_primary(5, paddr, 7);
+        case 2:         return __kmap_atomic_primary(6, paddr, 8);
+        case 3:         return __kmap_atomic_primary(7, paddr, 9);
+        case 4:         return __kmap_atomic_primary(8, paddr, 10);
+
+        case 5 ... 5 + NR_TLB_LINES - 1:
+                return __kmap_atomic_secondary(type - 5, paddr);
+
+        default:
+                BUG();
+                return NULL;
+        }
+}
+EXPORT_SYMBOL(__kmap_atomic);
+
+void __kunmap_atomic(void *kvaddr)
+{
+        int type = kmap_atomic_idx_pop();
+        switch (type) {
+        case 0:         __kunmap_atomic_primary(4, 6);  break;
+        case 1:         __kunmap_atomic_primary(5, 7);  break;
+        case 2:         __kunmap_atomic_primary(6, 8);  break;
+        case 3:         __kunmap_atomic_primary(7, 9);  break;
+        case 4:         __kunmap_atomic_primary(8, 10); break;
+
+        case 5 ... 5 + NR_TLB_LINES - 1:
+                __kunmap_atomic_secondary(type - 5, kvaddr);
+                break;
+
+        default:
+                BUG();
+        }
+        pagefault_enable();
+}
+EXPORT_SYMBOL(__kunmap_atomic);
diff --git a/arch/mips/include/asm/highmem.h b/arch/mips/include/asm/highmem.h
index 75753ca73bfd..77e644082a3b 100644
--- a/arch/mips/include/asm/highmem.h
+++ b/arch/mips/include/asm/highmem.h
@@ -45,18 +45,12 @@ extern pte_t *pkmap_page_table;
 extern void * kmap_high(struct page *page);
 extern void kunmap_high(struct page *page);
 
-extern void *__kmap(struct page *page);
-extern void __kunmap(struct page *page);
-extern void *__kmap_atomic(struct page *page, enum km_type type);
-extern void __kunmap_atomic_notypecheck(void *kvaddr, enum km_type type);
-extern void *kmap_atomic_pfn(unsigned long pfn, enum km_type type);
-extern struct page *__kmap_atomic_to_page(void *ptr);
-
-#define kmap                    __kmap
-#define kunmap                  __kunmap
-#define kmap_atomic             __kmap_atomic
-#define kunmap_atomic_notypecheck               __kunmap_atomic_notypecheck
-#define kmap_atomic_to_page     __kmap_atomic_to_page
+extern void *kmap(struct page *page);
+extern void kunmap(struct page *page);
+extern void *__kmap_atomic(struct page *page);
+extern void __kunmap_atomic(void *kvaddr);
+extern void *kmap_atomic_pfn(unsigned long pfn);
+extern struct page *kmap_atomic_to_page(void *ptr);
 
 #define flush_cache_kmaps()     flush_cache_all()
 
diff --git a/arch/mips/mm/highmem.c b/arch/mips/mm/highmem.c
index 6a2b1bf9ef11..1e69b1fb4b85 100644
--- a/arch/mips/mm/highmem.c
+++ b/arch/mips/mm/highmem.c
@@ -9,7 +9,7 @@ static pte_t *kmap_pte;
 
 unsigned long highstart_pfn, highend_pfn;
 
-void *__kmap(struct page *page)
+void *kmap(struct page *page)
 {
         void *addr;
 
@@ -21,16 +21,16 @@ void *__kmap(struct page *page)
 
         return addr;
 }
-EXPORT_SYMBOL(__kmap);
+EXPORT_SYMBOL(kmap);
 
-void __kunmap(struct page *page)
+void kunmap(struct page *page)
 {
         BUG_ON(in_interrupt());
         if (!PageHighMem(page))
                 return;
         kunmap_high(page);
 }
-EXPORT_SYMBOL(__kunmap);
+EXPORT_SYMBOL(kunmap);
 
 /*
  * kmap_atomic/kunmap_atomic is significantly faster than kmap/kunmap because
@@ -41,17 +41,17 @@ EXPORT_SYMBOL(__kunmap);
  * kmaps are appropriate for short, tight code paths only.
  */
 
-void *__kmap_atomic(struct page *page, enum km_type type)
+void *__kmap_atomic(struct page *page)
 {
-        enum fixed_addresses idx;
         unsigned long vaddr;
+        int idx, type;
 
         /* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
         pagefault_disable();
         if (!PageHighMem(page))
                 return page_address(page);
 
-        debug_kmap_atomic(type);
+        type = kmap_atomic_idx_push();
         idx = type + KM_TYPE_NR*smp_processor_id();
         vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
 #ifdef CONFIG_DEBUG_HIGHMEM
@@ -64,43 +64,47 @@ void *__kmap_atomic(struct page *page, enum km_type type)
 }
 EXPORT_SYMBOL(__kmap_atomic);
 
-void __kunmap_atomic_notypecheck(void *kvaddr, enum km_type type)
+void __kunmap_atomic(void *kvaddr)
 {
-#ifdef CONFIG_DEBUG_HIGHMEM
         unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-        enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id();
+        int type;
 
         if (vaddr < FIXADDR_START) { // FIXME
                 pagefault_enable();
                 return;
         }
 
-        BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
+        type = kmap_atomic_idx_pop();
+#ifdef CONFIG_DEBUG_HIGHMEM
+        {
+                int idx = type + KM_TYPE_NR * smp_processor_id();
 
-        /*
-         * force other mappings to Oops if they'll try to access
-         * this pte without first remap it
-         */
-        pte_clear(&init_mm, vaddr, kmap_pte-idx);
-        local_flush_tlb_one(vaddr);
-#endif
+                BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
 
+                /*
+                 * force other mappings to Oops if they'll try to access
+                 * this pte without first remap it
+                 */
+                pte_clear(&init_mm, vaddr, kmap_pte-idx);
+                local_flush_tlb_one(vaddr);
+        }
+#endif
         pagefault_enable();
 }
-EXPORT_SYMBOL(__kunmap_atomic_notypecheck);
+EXPORT_SYMBOL(__kunmap_atomic);
 
 /*
  * This is the same as kmap_atomic() but can map memory that doesn't
  * have a struct page associated with it.
  */
-void *kmap_atomic_pfn(unsigned long pfn, enum km_type type)
+void *kmap_atomic_pfn(unsigned long pfn)
 {
-        enum fixed_addresses idx;
         unsigned long vaddr;
+        int idx, type;
 
         pagefault_disable();
 
-        debug_kmap_atomic(type);
+        type = kmap_atomic_idx_push();
         idx = type + KM_TYPE_NR*smp_processor_id();
         vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
         set_pte(kmap_pte-idx, pfn_pte(pfn, PAGE_KERNEL));
@@ -109,7 +113,7 @@ void *kmap_atomic_pfn(unsigned long pfn, enum km_type type)
         return (void*) vaddr;
 }
 
-struct page *__kmap_atomic_to_page(void *ptr)
+struct page *kmap_atomic_to_page(void *ptr)
 {
         unsigned long idx, vaddr = (unsigned long)ptr;
         pte_t *pte;
diff --git a/arch/mn10300/include/asm/highmem.h b/arch/mn10300/include/asm/highmem.h
index b0b187a29b88..f577ba2268ca 100644
--- a/arch/mn10300/include/asm/highmem.h
+++ b/arch/mn10300/include/asm/highmem.h
@@ -70,15 +70,16 @@ static inline void kunmap(struct page *page)
  * be used in IRQ contexts, so in some (very limited) cases we need
  * it.
  */
-static inline unsigned long kmap_atomic(struct page *page, enum km_type type)
+static inline unsigned long __kmap_atomic(struct page *page)
 {
-        enum fixed_addresses idx;
         unsigned long vaddr;
+        int idx, type;
 
+        pagefault_disable();
         if (page < highmem_start_page)
                 return page_address(page);
 
-        debug_kmap_atomic(type);
+        type = kmap_atomic_idx_push();
         idx = type + KM_TYPE_NR * smp_processor_id();
         vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
 #if HIGHMEM_DEBUG
@@ -91,26 +92,35 @@ static inline unsigned long kmap_atomic(struct page *page, enum km_type type)
         return vaddr;
 }
 
-static inline void kunmap_atomic_notypecheck(unsigned long vaddr, enum km_type type)
+static inline void __kunmap_atomic(unsigned long vaddr)
 {
-#if HIGHMEM_DEBUG
-        enum fixed_addresses idx = type + KM_TYPE_NR * smp_processor_id();
+        int type;
 
-        if (vaddr < FIXADDR_START) /* FIXME */
+        if (vaddr < FIXADDR_START) { /* FIXME */
+                pagefault_enable();
                 return;
+        }
 
-        if (vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx))
-                BUG();
+        type = kmap_atomic_idx_pop();
 
-        /*
-         * force other mappings to Oops if they'll try to access
-         * this pte without first remap it
-         */
-        pte_clear(kmap_pte - idx);
-        __flush_tlb_one(vaddr);
+#if HIGHMEM_DEBUG
+        {
+                unsigned int idx;
+                idx = type + KM_TYPE_NR * smp_processor_id();
+
+                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
+                 */
+                pte_clear(kmap_pte - idx);
+                __flush_tlb_one(vaddr);
+        }
 #endif
+        pagefault_enable();
 }
-
 #endif /* __KERNEL__ */
 
 #endif /* _ASM_HIGHMEM_H */
diff --git a/arch/powerpc/include/asm/highmem.h b/arch/powerpc/include/asm/highmem.h
index d10d64a4be38..dbc264010d0b 100644
--- a/arch/powerpc/include/asm/highmem.h
+++ b/arch/powerpc/include/asm/highmem.h
@@ -60,9 +60,8 @@ extern pte_t *pkmap_page_table;
 
 extern void *kmap_high(struct page *page);
 extern void kunmap_high(struct page *page);
-extern void *kmap_atomic_prot(struct page *page, enum km_type type,
-                              pgprot_t prot);
-extern void kunmap_atomic_notypecheck(void *kvaddr, enum km_type type);
+extern void *kmap_atomic_prot(struct page *page, pgprot_t prot);
+extern void __kunmap_atomic(void *kvaddr);
 
 static inline void *kmap(struct page *page)
 {
@@ -80,9 +79,9 @@ static inline void kunmap(struct page *page)
         kunmap_high(page);
 }
 
-static inline void *kmap_atomic(struct page *page, enum km_type type)
+static inline void *__kmap_atomic(struct page *page)
 {
-        return kmap_atomic_prot(page, type, kmap_prot);
+        return kmap_atomic_prot(page, kmap_prot);
 }
 
 static inline struct page *kmap_atomic_to_page(void *ptr)
diff --git a/arch/powerpc/mm/highmem.c b/arch/powerpc/mm/highmem.c
index 857d4173f9c6..b0848b462bbc 100644
--- a/arch/powerpc/mm/highmem.c
+++ b/arch/powerpc/mm/highmem.c
@@ -29,17 +29,17 @@
  * be used in IRQ contexts, so in some (very limited) cases we need
  * it.
  */
-void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot)
+void *kmap_atomic_prot(struct page *page, pgprot_t prot)
 {
-        unsigned int idx;
         unsigned long vaddr;
+        int idx, type;
 
         /* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
         pagefault_disable();
         if (!PageHighMem(page))
                 return page_address(page);
 
-        debug_kmap_atomic(type);
+        type = kmap_atomic_idx_push();
         idx = type + KM_TYPE_NR*smp_processor_id();
         vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
 #ifdef CONFIG_DEBUG_HIGHMEM
@@ -52,26 +52,33 @@ void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot)
 }
 EXPORT_SYMBOL(kmap_atomic_prot);
 
-void kunmap_atomic_notypecheck(void *kvaddr, enum km_type type)
+void __kunmap_atomic(void *kvaddr)
 {
-#ifdef CONFIG_DEBUG_HIGHMEM
         unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-        enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id();
+        int type;
 
         if (vaddr < __fix_to_virt(FIX_KMAP_END)) {
                 pagefault_enable();
                 return;
         }
 
-        BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
+        type = kmap_atomic_idx_pop();
 
-        /*
-         * force other mappings to Oops if they'll try to access
-         * this pte without first remap it
-         */
-        pte_clear(&init_mm, vaddr, kmap_pte-idx);
-        local_flush_tlb_page(NULL, vaddr);
+#ifdef CONFIG_DEBUG_HIGHMEM
+        {
+                unsigned int idx;
+
+                idx = type + KM_TYPE_NR * smp_processor_id();
+                BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
+
+                /*
+                 * force other mappings to Oops if they'll try to access
+                 * this pte without first remap it
+                 */
+                pte_clear(&init_mm, vaddr, kmap_pte-idx);
+                local_flush_tlb_page(NULL, vaddr);
+        }
 #endif
         pagefault_enable();
 }
-EXPORT_SYMBOL(kunmap_atomic_notypecheck);
+EXPORT_SYMBOL(__kunmap_atomic);
diff --git a/arch/sparc/include/asm/highmem.h b/arch/sparc/include/asm/highmem.h
index ec23b0a87b98..3d7afbb7f4bb 100644
--- a/arch/sparc/include/asm/highmem.h
+++ b/arch/sparc/include/asm/highmem.h
@@ -70,8 +70,8 @@ static inline void kunmap(struct page *page)
         kunmap_high(page);
 }
 
-extern void *kmap_atomic(struct page *page, enum km_type type);
-extern void kunmap_atomic_notypecheck(void *kvaddr, enum km_type type);
+extern void *__kmap_atomic(struct page *page);
+extern void __kunmap_atomic(void *kvaddr);
 extern struct page *kmap_atomic_to_page(void *vaddr);
 
 #define flush_cache_kmaps()     flush_cache_all()
diff --git a/arch/sparc/mm/highmem.c b/arch/sparc/mm/highmem.c
index e139e9cbf5f7..5e50c09b7dce 100644
--- a/arch/sparc/mm/highmem.c
+++ b/arch/sparc/mm/highmem.c
@@ -29,17 +29,17 @@
 #include <asm/tlbflush.h>
 #include <asm/fixmap.h>
 
-void *kmap_atomic(struct page *page, enum km_type type)
+void *__kmap_atomic(struct page *page)
 {
-        unsigned long idx;
         unsigned long vaddr;
+        long idx, type;
 
         /* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
         pagefault_disable();
         if (!PageHighMem(page))
                 return page_address(page);
 
-        debug_kmap_atomic(type);
+        type = kmap_atomic_idx_push();
         idx = type + KM_TYPE_NR*smp_processor_id();
         vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
 
@@ -63,44 +63,50 @@ void *kmap_atomic(struct page *page, enum km_type type)
 
         return (void*) vaddr;
 }
-EXPORT_SYMBOL(kmap_atomic);
+EXPORT_SYMBOL(__kmap_atomic);
 
-void kunmap_atomic_notypecheck(void *kvaddr, enum km_type type)
+void __kunmap_atomic(void *kvaddr)
 {
-#ifdef CONFIG_DEBUG_HIGHMEM
         unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-        unsigned long idx = type + KM_TYPE_NR*smp_processor_id();
+        int type;
 
         if (vaddr < FIXADDR_START) { // FIXME
                 pagefault_enable();
                 return;
         }
 
-        BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN+idx));
+        type = kmap_atomic_idx_pop();
 
-/* XXX Fix - Anton */
+#ifdef CONFIG_DEBUG_HIGHMEM
+        {
+                unsigned long idx;
+
+                idx = type + KM_TYPE_NR * smp_processor_id();
+                BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN+idx));
+
+                /* XXX Fix - Anton */
 #if 0
-        __flush_cache_one(vaddr);
+                __flush_cache_one(vaddr);
 #else
-        flush_cache_all();
+                flush_cache_all();
 #endif
 
-        /*
-         * force other mappings to Oops if they'll try to access
-         * this pte without first remap it
-         */
-        pte_clear(&init_mm, vaddr, kmap_pte-idx);
-/* XXX Fix - Anton */
+                /*
+                 * force other mappings to Oops if they'll try to access
+                 * this pte without first remap it
+                 */
+                pte_clear(&init_mm, vaddr, kmap_pte-idx);
+                /* XXX Fix - Anton */
 #if 0
-        __flush_tlb_one(vaddr);
+                __flush_tlb_one(vaddr);
 #else
-        flush_tlb_all();
+                flush_tlb_all();
 #endif
+        }
 #endif
-
         pagefault_enable();
 }
-EXPORT_SYMBOL(kunmap_atomic_notypecheck);
+EXPORT_SYMBOL(__kunmap_atomic);
 
 /* We may be fed a pagetable here by ptep_to_xxx and others. */
 struct page *kmap_atomic_to_page(void *ptr)
diff --git a/arch/tile/include/asm/highmem.h b/arch/tile/include/asm/highmem.h
index d155db6fa9bd..e0f7ee186721 100644
--- a/arch/tile/include/asm/highmem.h
+++ b/arch/tile/include/asm/highmem.h
@@ -60,12 +60,12 @@ void *kmap_fix_kpte(struct page *page, int finished);
 /* This macro is used only in map_new_virtual() to map "page". */
 #define kmap_prot page_to_kpgprot(page)
 
-void kunmap_atomic_notypecheck(void *kvaddr, enum km_type type);
-void *kmap_atomic_pfn(unsigned long pfn, enum km_type type);
-void *kmap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot);
+void *__kmap_atomic(struct page *page);
+void __kunmap_atomic(void *kvaddr);
+void *kmap_atomic_pfn(unsigned long pfn);
+void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot);
 struct page *kmap_atomic_to_page(void *ptr);
-void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot);
-void *kmap_atomic(struct page *page, enum km_type type);
+void *kmap_atomic_prot(struct page *page, pgprot_t prot);
 void kmap_atomic_fix_kpte(struct page *page, int finished);
 
 #define flush_cache_kmaps()     do { } while (0)
diff --git a/arch/tile/mm/highmem.c b/arch/tile/mm/highmem.c
index 12ab137e7d4f..8ef6595e162c 100644
--- a/arch/tile/mm/highmem.c
+++ b/arch/tile/mm/highmem.c
@@ -56,50 +56,6 @@ void kunmap(struct page *page)
 }
 EXPORT_SYMBOL(kunmap);
 
-static void debug_kmap_atomic_prot(enum km_type type)
-{
-#ifdef CONFIG_DEBUG_HIGHMEM
-        static unsigned warn_count = 10;
-
-        if (unlikely(warn_count == 0))
-                return;
-
-        if (unlikely(in_interrupt())) {
-                if (in_irq()) {
-                        if (type != KM_IRQ0 && type != KM_IRQ1 &&
-                            type != KM_BIO_SRC_IRQ &&
-                            /* type != KM_BIO_DST_IRQ && */
-                            type != KM_BOUNCE_READ) {
-                                WARN_ON(1);
-                                warn_count--;
-                        }
-                } else if (!irqs_disabled()) {  /* softirq */
-                        if (type != KM_IRQ0 && type != KM_IRQ1 &&
-                            type != KM_SOFTIRQ0 && type != KM_SOFTIRQ1 &&
-                            type != KM_SKB_SUNRPC_DATA &&
-                            type != KM_SKB_DATA_SOFTIRQ &&
-                            type != KM_BOUNCE_READ) {
-                                WARN_ON(1);
-                                warn_count--;
-                        }
-                }
-        }
-
-        if (type == KM_IRQ0 || type == KM_IRQ1 || type == KM_BOUNCE_READ ||
-            type == KM_BIO_SRC_IRQ /* || type == KM_BIO_DST_IRQ */) {
-                if (!irqs_disabled()) {
-                        WARN_ON(1);
-                        warn_count--;
-                }
-        } else if (type == KM_SOFTIRQ0 || type == KM_SOFTIRQ1) {
-                if (irq_count() == 0 && !irqs_disabled()) {
-                        WARN_ON(1);
-                        warn_count--;
-                }
-        }
-#endif
-}
-
 /*
  * Describe a single atomic mapping of a page on a given cpu at a
  * given address, and allow it to be linked into a list.
@@ -240,10 +196,10 @@ void kmap_atomic_fix_kpte(struct page *page, int finished)
  * When holding an atomic kmap is is not legal to sleep, so atomic
  * kmaps are appropriate for short, tight code paths only.
  */
-void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot)
+void *kmap_atomic_prot(struct page *page, pgprot_t prot)
 {
-        enum fixed_addresses idx;
         unsigned long vaddr;
+        int idx, type;
         pte_t *pte;
 
         /* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
@@ -255,8 +211,7 @@ void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot)
         if (!PageHighMem(page))
                 return page_address(page);
 
-        debug_kmap_atomic_prot(type);
-
+        type = kmap_atomic_idx_push();
         idx = type + KM_TYPE_NR*smp_processor_id();
         vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
         pte = kmap_get_pte(vaddr);
@@ -269,25 +224,31 @@ void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot)
 }
 EXPORT_SYMBOL(kmap_atomic_prot);
 
-void *kmap_atomic(struct page *page, enum km_type type)
+void *__kmap_atomic(struct page *page)
 {
         /* PAGE_NONE is a magic value that tells us to check immutability. */
         return kmap_atomic_prot(page, type, PAGE_NONE);
 }
-EXPORT_SYMBOL(kmap_atomic);
+EXPORT_SYMBOL(__kmap_atomic);
 
-void kunmap_atomic_notypecheck(void *kvaddr, enum km_type type)
+void __kunmap_atomic(void *kvaddr)
 {
         unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-        enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id();
 
-        /*
-         * Force other mappings to Oops if they try to access this pte without
-         * first remapping it.  Keeping stale mappings around is a bad idea.
-         */
-        if (vaddr == __fix_to_virt(FIX_KMAP_BEGIN+idx)) {
+        if (vaddr >= __fix_to_virt(FIX_KMAP_END) &&
+            vaddr <= __fix_to_virt(FIX_KMAP_BEGIN)) {
                 pte_t *pte = kmap_get_pte(vaddr);
                 pte_t pteval = *pte;
+                int idx, type;
+
+                type = kmap_atomic_idx_pop();
+                idx = type + KM_TYPE_NR*smp_processor_id();
+
+                /*
+                 * Force other mappings to Oops if they try to access this pte
+                 * without first remapping it.  Keeping stale mappings around
+                 * is a bad idea.
+                 */
                 BUG_ON(!pte_present(pteval) && !pte_migrating(pteval));
                 kmap_atomic_unregister(pte_page(pteval), vaddr);
                 kpte_clear_flush(pte, vaddr);
@@ -300,19 +261,19 @@ void kunmap_atomic_notypecheck(void *kvaddr, enum km_type type)
         arch_flush_lazy_mmu_mode();
         pagefault_enable();
 }
-EXPORT_SYMBOL(kunmap_atomic_notypecheck);
+EXPORT_SYMBOL(__kunmap_atomic);
 
 /*
  * This API is supposed to allow us to map memory without a "struct page".
  * Currently we don't support this, though this may change in the future.
  */
-void *kmap_atomic_pfn(unsigned long pfn, enum km_type type)
+void *kmap_atomic_pfn(unsigned long pfn)
 {
-        return kmap_atomic(pfn_to_page(pfn), type);
+        return kmap_atomic(pfn_to_page(pfn));
 }
-void *kmap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot)
+void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
 {
-        return kmap_atomic_prot(pfn_to_page(pfn), type, prot);
+        return kmap_atomic_prot(pfn_to_page(pfn), prot);
 }
 
 struct page *kmap_atomic_to_page(void *ptr)
diff --git a/arch/x86/include/asm/highmem.h b/arch/x86/include/asm/highmem.h
index 8caac76ac324..3bd04022fd0c 100644
--- a/arch/x86/include/asm/highmem.h
+++ b/arch/x86/include/asm/highmem.h
@@ -59,11 +59,12 @@ extern void kunmap_high(struct page *page);
 
 void *kmap(struct page *page);
 void kunmap(struct page *page);
-void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot);
-void *kmap_atomic(struct page *page, enum km_type type);
-void kunmap_atomic_notypecheck(void *kvaddr, enum km_type type);
-void *kmap_atomic_pfn(unsigned long pfn, enum km_type type);
-void *kmap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot);
+
+void *kmap_atomic_prot(struct page *page, pgprot_t prot);
+void *__kmap_atomic(struct page *page);
+void __kunmap_atomic(void *kvaddr);
+void *kmap_atomic_pfn(unsigned long pfn);
+void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot);
 struct page *kmap_atomic_to_page(void *ptr);
 
 #define flush_cache_kmaps()     do { } while (0)
diff --git a/arch/x86/include/asm/iomap.h b/arch/x86/include/asm/iomap.h
index c4191b3b7056..363e33eb6ec1 100644
--- a/arch/x86/include/asm/iomap.h
+++ b/arch/x86/include/asm/iomap.h
@@ -27,10 +27,10 @@
 #include <asm/tlbflush.h>
 
 void __iomem *
-iomap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot);
+iomap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot);
 
 void
-iounmap_atomic(void __iomem *kvaddr, enum km_type type);
+iounmap_atomic(void __iomem *kvaddr);
 
 int
 iomap_create_wc(resource_size_t base, unsigned long size, pgprot_t *prot);
diff --git a/arch/x86/kernel/crash_dump_32.c b/arch/x86/kernel/crash_dump_32.c
index 67414550c3cc..d5cd13945d5a 100644
--- a/arch/x86/kernel/crash_dump_32.c
+++ b/arch/x86/kernel/crash_dump_32.c
@@ -61,7 +61,7 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
         if (!is_crashed_pfn_valid(pfn))
                 return -EFAULT;
 
-        vaddr = kmap_atomic_pfn(pfn, KM_PTE0);
+        vaddr = kmap_atomic_pfn(pfn);
 
         if (!userbuf) {
                 memcpy(buf, (vaddr + offset), csize);
diff --git a/arch/x86/mm/highmem_32.c b/arch/x86/mm/highmem_32.c
index 5e8fa12ef861..d723e369003c 100644
--- a/arch/x86/mm/highmem_32.c
+++ b/arch/x86/mm/highmem_32.c
@@ -9,6 +9,7 @@ void *kmap(struct page *page)
                 return page_address(page);
         return kmap_high(page);
 }
+EXPORT_SYMBOL(kmap);
 
 void kunmap(struct page *page)
 {
@@ -18,6 +19,7 @@ void kunmap(struct page *page)
                 return;
         kunmap_high(page);
 }
+EXPORT_SYMBOL(kunmap);
 
 /*
  * kmap_atomic/kunmap_atomic is significantly faster than kmap/kunmap because
@@ -27,10 +29,10 @@ void kunmap(struct page *page)
  * However when holding an atomic kmap it is not legal to sleep, so atomic
  * kmaps are appropriate for short, tight code paths only.
  */
-void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot)
+void *kmap_atomic_prot(struct page *page, pgprot_t prot)
 {
-        enum fixed_addresses idx;
         unsigned long vaddr;
+        int idx, type;
 
         /* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
         pagefault_disable();
@@ -38,8 +40,7 @@ void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot)
         if (!PageHighMem(page))
                 return page_address(page);
 
-        debug_kmap_atomic(type);
-
+        type = kmap_atomic_idx_push();
         idx = type + KM_TYPE_NR*smp_processor_id();
         vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
         BUG_ON(!pte_none(*(kmap_pte-idx)));
@@ -47,44 +48,56 @@ void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot)
 
         return (void *)vaddr;
 }
+EXPORT_SYMBOL(kmap_atomic_prot);
+
+void *__kmap_atomic(struct page *page)
+{
+        return kmap_atomic_prot(page, kmap_prot);
+}
+EXPORT_SYMBOL(__kmap_atomic);
 
-void *kmap_atomic(struct page *page, enum km_type type)
+/*
+ * This is the same as kmap_atomic() but can map memory that doesn't
+ * have a struct page associated with it.
+ */
+void *kmap_atomic_pfn(unsigned long pfn)
 {
-        return kmap_atomic_prot(page, type, kmap_prot);
+        return kmap_atomic_prot_pfn(pfn, kmap_prot);
 }
+EXPORT_SYMBOL_GPL(kmap_atomic_pfn);
 
-void kunmap_atomic_notypecheck(void *kvaddr, enum km_type type)
+void __kunmap_atomic(void *kvaddr)
 {
         unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-        enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id();
-
-        /*
-         * 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.
-         */
-        if (vaddr == __fix_to_virt(FIX_KMAP_BEGIN+idx))
+
+        if (vaddr >= __fix_to_virt(FIX_KMAP_END) &&
+            vaddr <= __fix_to_virt(FIX_KMAP_BEGIN)) {
+                int idx, type;
+
+                type = kmap_atomic_idx_pop();
+                idx = type + KM_TYPE_NR * smp_processor_id();
+
+#ifdef CONFIG_DEBUG_HIGHMEM
+                WARN_ON_ONCE(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
+#endif
+                /*
+                 * 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.
+                 */
                 kpte_clear_flush(kmap_pte-idx, vaddr);
-        else {
+        }
 #ifdef CONFIG_DEBUG_HIGHMEM
+        else {
                 BUG_ON(vaddr < PAGE_OFFSET);
                 BUG_ON(vaddr >= (unsigned long)high_memory);
-#endif
         }
+#endif
 
         pagefault_enable();
 }
-
-/*
- * This is the same as kmap_atomic() but can map memory that doesn't
- * have a struct page associated with it.
- */
-void *kmap_atomic_pfn(unsigned long pfn, enum km_type type)
-{
-        return kmap_atomic_prot_pfn(pfn, type, kmap_prot);
-}
-EXPORT_SYMBOL_GPL(kmap_atomic_pfn); /* temporarily in use by i915 GEM until vmap */
+EXPORT_SYMBOL(__kunmap_atomic);
 
 struct page *kmap_atomic_to_page(void *ptr)
 {
@@ -98,12 +111,6 @@ struct page *kmap_atomic_to_page(void *ptr)
         pte = kmap_pte - (idx - FIX_KMAP_BEGIN);
         return pte_page(*pte);
 }
-
-EXPORT_SYMBOL(kmap);
-EXPORT_SYMBOL(kunmap);
-EXPORT_SYMBOL(kmap_atomic);
-EXPORT_SYMBOL(kunmap_atomic_notypecheck);
-EXPORT_SYMBOL(kmap_atomic_prot);
 EXPORT_SYMBOL(kmap_atomic_to_page);
 
 void __init set_highmem_pages_init(void)
diff --git a/arch/x86/mm/iomap_32.c b/arch/x86/mm/iomap_32.c
index 72fc70cf6184..75a3d7f24a2c 100644
--- a/arch/x86/mm/iomap_32.c
+++ b/arch/x86/mm/iomap_32.c
@@ -48,21 +48,20 @@ int iomap_create_wc(resource_size_t base, unsigned long size, pgprot_t *prot)
 }
 EXPORT_SYMBOL_GPL(iomap_create_wc);
 
-void
-iomap_free(resource_size_t base, unsigned long size)
+void iomap_free(resource_size_t base, unsigned long size)
 {
         io_free_memtype(base, base + size);
 }
 EXPORT_SYMBOL_GPL(iomap_free);
 
-void *kmap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot)
+void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
 {
-        enum fixed_addresses idx;
         unsigned long vaddr;
+        int idx, type;
 
         pagefault_disable();
 
-        debug_kmap_atomic(type);
+        type = kmap_atomic_idx_push();
         idx = type + KM_TYPE_NR * smp_processor_id();
         vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
         set_pte(kmap_pte - idx, pfn_pte(pfn, prot));
@@ -72,10 +71,10 @@ void *kmap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot)
 }
 
 /*
- * Map 'pfn' using fixed map 'type' and protections 'prot'
+ * Map 'pfn' using protections 'prot'
  */
 void __iomem *
-iomap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot)
+iomap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
 {
         /*
          * For non-PAT systems, promote PAGE_KERNEL_WC to PAGE_KERNEL_UC_MINUS.
@@ -86,24 +85,33 @@ iomap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot)
         if (!pat_enabled && pgprot_val(prot) == pgprot_val(PAGE_KERNEL_WC))
                 prot = PAGE_KERNEL_UC_MINUS;
 
-        return (void __force __iomem *) kmap_atomic_prot_pfn(pfn, type, prot);
+        return (void __force __iomem *) kmap_atomic_prot_pfn(pfn, prot);
 }
 EXPORT_SYMBOL_GPL(iomap_atomic_prot_pfn);
 
 void
-iounmap_atomic(void __iomem *kvaddr, enum km_type type)
+iounmap_atomic(void __iomem *kvaddr)
 {
         unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-        enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id();
 
-        /*
-         * 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.
-         */
-        if (vaddr == __fix_to_virt(FIX_KMAP_BEGIN+idx))
+        if (vaddr >= __fix_to_virt(FIX_KMAP_END) &&
+            vaddr <= __fix_to_virt(FIX_KMAP_BEGIN)) {
+                int idx, type;
+
+                type = kmap_atomic_idx_pop();
+                idx = type + KM_TYPE_NR * smp_processor_id();
+
+#ifdef CONFIG_DEBUG_HIGHMEM
+                WARN_ON_ONCE(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
+#endif
+                /*
+                 * 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.
+                 */
                 kpte_clear_flush(kmap_pte-idx, vaddr);
+        }
 
         pagefault_enable();
 }
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 90b1d6753b9d..eb6c473c6d1b 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -155,11 +155,11 @@ fast_shmem_read(struct page **pages,
         char __iomem *vaddr;
         int unwritten;
 
-        vaddr = kmap_atomic(pages[page_base >> PAGE_SHIFT], KM_USER0);
+        vaddr = kmap_atomic(pages[page_base >> PAGE_SHIFT]);
         if (vaddr == NULL)
                 return -ENOMEM;
         unwritten = __copy_to_user_inatomic(data, vaddr + page_offset, length);
-        kunmap_atomic(vaddr, KM_USER0);
+        kunmap_atomic(vaddr);
 
         if (unwritten)
                 return -EFAULT;
@@ -509,10 +509,10 @@ fast_user_write(struct io_mapping *mapping,
         char *vaddr_atomic;
         unsigned long unwritten;
 
-        vaddr_atomic = io_mapping_map_atomic_wc(mapping, page_base, KM_USER0);
+        vaddr_atomic = io_mapping_map_atomic_wc(mapping, page_base);
         unwritten = __copy_from_user_inatomic_nocache(vaddr_atomic + page_offset,
                                                       user_data, length);
-        io_mapping_unmap_atomic(vaddr_atomic, KM_USER0);
+        io_mapping_unmap_atomic(vaddr_atomic);
         if (unwritten)
                 return -EFAULT;
         return 0;
@@ -551,11 +551,11 @@ fast_shmem_write(struct page **pages,
         char __iomem *vaddr;
         unsigned long unwritten;
 
-        vaddr = kmap_atomic(pages[page_base >> PAGE_SHIFT], KM_USER0);
+        vaddr = kmap_atomic(pages[page_base >> PAGE_SHIFT]);
         if (vaddr == NULL)
                 return -ENOMEM;
         unwritten = __copy_from_user_inatomic(vaddr + page_offset, data, length);
-        kunmap_atomic(vaddr, KM_USER0);
+        kunmap_atomic(vaddr);
 
         if (unwritten)
                 return -EFAULT;
@@ -3346,8 +3346,7 @@ i915_gem_object_pin_and_relocate(struct drm_gem_object *obj,
                 reloc_offset = obj_priv->gtt_offset + reloc->offset;
                 reloc_page = io_mapping_map_atomic_wc(dev_priv->mm.gtt_mapping,
                                                       (reloc_offset &
-                                                       ~(PAGE_SIZE - 1)),
-                                                      KM_USER0);
+                                                       ~(PAGE_SIZE - 1)));
                 reloc_entry = (uint32_t __iomem *)(reloc_page +
                                                    (reloc_offset & (PAGE_SIZE - 1)));
                 reloc_val = target_obj_priv->gtt_offset + reloc->delta;
@@ -3358,7 +3357,7 @@ i915_gem_object_pin_and_relocate(struct drm_gem_object *obj,
                           readl(reloc_entry), reloc_val);
 #endif
                 writel(reloc_val, reloc_entry);
-                io_mapping_unmap_atomic(reloc_page, KM_USER0);
+                io_mapping_unmap_atomic(reloc_page);
 
                 /* The updated presumed offset for this entry will be
                  * copied back out to the user.
@@ -4772,11 +4771,11 @@ void i915_gem_detach_phys_object(struct drm_device *dev,
         page_count = obj->size / PAGE_SIZE;
 
         for (i = 0; i < page_count; i++) {
-                char *dst = kmap_atomic(obj_priv->pages[i], KM_USER0);
+                char *dst = kmap_atomic(obj_priv->pages[i]);
                 char *src = obj_priv->phys_obj->handle->vaddr + (i * PAGE_SIZE);
 
                 memcpy(dst, src, PAGE_SIZE);
-                kunmap_atomic(dst, KM_USER0);
+                kunmap_atomic(dst);
         }
         drm_clflush_pages(obj_priv->pages, page_count);
         drm_agp_chipset_flush(dev);
@@ -4833,11 +4832,11 @@ i915_gem_attach_phys_object(struct drm_device *dev,
         page_count = obj->size / PAGE_SIZE;
 
         for (i = 0; i < page_count; i++) {
-                char *src = kmap_atomic(obj_priv->pages[i], KM_USER0);
+                char *src = kmap_atomic(obj_priv->pages[i]);
                 char *dst = obj_priv->phys_obj->handle->vaddr + (i * PAGE_SIZE);
 
                 memcpy(dst, src, PAGE_SIZE);
-                kunmap_atomic(src, KM_USER0);
+                kunmap_atomic(src);
         }
 
         i915_gem_object_put_pages(obj);
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 744225ebb4b2..b80010f0c4c9 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -456,10 +456,9 @@ i915_error_object_create(struct drm_device *dev,
 
                 local_irq_save(flags);
                 s = io_mapping_map_atomic_wc(dev_priv->mm.gtt_mapping,
-                                             reloc_offset,
-                                             KM_IRQ0);
+                                             reloc_offset);
                 memcpy_fromio(d, s, PAGE_SIZE);
-                io_mapping_unmap_atomic(s, KM_IRQ0);
+                io_mapping_unmap_atomic(s);
                 local_irq_restore(flags);
 
                 dst->pages[page] = d;
diff --git a/drivers/gpu/drm/i915/intel_overlay.c b/drivers/gpu/drm/i915/intel_overlay.c
index 1d306a458be6..3264bbd47e65 100644
--- a/drivers/gpu/drm/i915/intel_overlay.c
+++ b/drivers/gpu/drm/i915/intel_overlay.c
@@ -187,8 +187,7 @@ static struct overlay_registers *intel_overlay_map_regs_atomic(struct intel_over
 
         if (OVERLAY_NONPHYSICAL(overlay->dev)) {
                 regs = io_mapping_map_atomic_wc(dev_priv->mm.gtt_mapping,
-                                                overlay->reg_bo->gtt_offset,
-                                                KM_USER0);
+                                                overlay->reg_bo->gtt_offset);
 
                 if (!regs) {
                         DRM_ERROR("failed to map overlay regs in GTT\n");
@@ -203,7 +202,7 @@ static struct overlay_registers *intel_overlay_map_regs_atomic(struct intel_over
 static void intel_overlay_unmap_regs_atomic(struct intel_overlay *overlay)
 {
         if (OVERLAY_NONPHYSICAL(overlay->dev))
-                io_mapping_unmap_atomic(overlay->virt_addr, KM_USER0);
+                io_mapping_unmap_atomic(overlay->virt_addr);
 
         overlay->virt_addr = NULL;
 
diff --git a/drivers/gpu/drm/nouveau/nouveau_bios.c b/drivers/gpu/drm/nouveau/nouveau_bios.c
index 974b0f8ae048..8fa339600fe3 100644
--- a/drivers/gpu/drm/nouveau/nouveau_bios.c
+++ b/drivers/gpu/drm/nouveau/nouveau_bios.c
@@ -2167,11 +2167,11 @@ peek_fb(struct drm_device *dev, struct io_mapping *fb,
 
         if (off < pci_resource_len(dev->pdev, 1)) {
                 uint8_t __iomem *p =
-                        io_mapping_map_atomic_wc(fb, off & PAGE_MASK, KM_USER0);
+                        io_mapping_map_atomic_wc(fb, off & PAGE_MASK);
 
                 val = ioread32(p + (off & ~PAGE_MASK));
 
-                io_mapping_unmap_atomic(p, KM_USER0);
+                io_mapping_unmap_atomic(p);
         }
 
         return val;
@@ -2183,12 +2183,12 @@ poke_fb(struct drm_device *dev, struct io_mapping *fb,
 {
         if (off < pci_resource_len(dev->pdev, 1)) {
                 uint8_t __iomem *p =
-                        io_mapping_map_atomic_wc(fb, off & PAGE_MASK, KM_USER0);
+                        io_mapping_map_atomic_wc(fb, off & PAGE_MASK);
 
                 iowrite32(val, p + (off & ~PAGE_MASK));
                 wmb();
 
-                io_mapping_unmap_atomic(p, KM_USER0);
+                io_mapping_unmap_atomic(p);
         }
 }
 
diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c
index 3451a82adba7..e8a73e65da69 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -170,7 +170,7 @@ static int ttm_copy_io_ttm_page(struct ttm_tt *ttm, void *src,
         src = (void *)((unsigned long)src + (page << PAGE_SHIFT));
 
 #ifdef CONFIG_X86
-        dst = kmap_atomic_prot(d, KM_USER0, prot);
+        dst = kmap_atomic_prot(d, prot);
 #else
         if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL))
                 dst = vmap(&d, 1, 0, prot);
@@ -183,7 +183,7 @@ static int ttm_copy_io_ttm_page(struct ttm_tt *ttm, void *src,
         memcpy_fromio(dst, src, PAGE_SIZE);
 
 #ifdef CONFIG_X86
-        kunmap_atomic(dst, KM_USER0);
+        kunmap_atomic(dst);
 #else
         if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL))
                 vunmap(dst);
@@ -206,7 +206,7 @@ static int ttm_copy_ttm_io_page(struct ttm_tt *ttm, void *dst,
 
         dst = (void *)((unsigned long)dst + (page << PAGE_SHIFT));
 #ifdef CONFIG_X86
-        src = kmap_atomic_prot(s, KM_USER0, prot);
+        src = kmap_atomic_prot(s, prot);
 #else
         if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL))
                 src = vmap(&s, 1, 0, prot);
@@ -219,7 +219,7 @@ static int ttm_copy_ttm_io_page(struct ttm_tt *ttm, void *dst,
         memcpy_toio(dst, src, PAGE_SIZE);
 
 #ifdef CONFIG_X86
-        kunmap_atomic(src, KM_USER0);
+        kunmap_atomic(src);
 #else
         if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL))
                 vunmap(src);
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
diff --git a/include/linux/io-mapping.h b/include/linux/io-mapping.h
index 7fb592793738..8cdcc2a199ad 100644
--- a/include/linux/io-mapping.h
+++ b/include/linux/io-mapping.h
@@ -81,8 +81,7 @@ io_mapping_free(struct io_mapping *mapping)
 /* Atomic map/unmap */
 static inline void __iomem *
 io_mapping_map_atomic_wc(struct io_mapping *mapping,
-                         unsigned long offset,
-                         int slot)
+                         unsigned long offset)
 {
         resource_size_t phys_addr;
         unsigned long pfn;
@@ -90,13 +89,13 @@ io_mapping_map_atomic_wc(struct io_mapping *mapping,
         BUG_ON(offset >= mapping->size);
         phys_addr = mapping->base + offset;
         pfn = (unsigned long) (phys_addr >> PAGE_SHIFT);
-        return iomap_atomic_prot_pfn(pfn, slot, mapping->prot);
+        return iomap_atomic_prot_pfn(pfn, mapping->prot);
 }
 
 static inline void
-io_mapping_unmap_atomic(void __iomem *vaddr, int slot)
+io_mapping_unmap_atomic(void __iomem *vaddr)
 {
-        iounmap_atomic(vaddr, slot);
+        iounmap_atomic(vaddr);
 }
 
 static inline void __iomem *
@@ -137,14 +136,13 @@ io_mapping_free(struct io_mapping *mapping)
 /* Atomic map/unmap */
 static inline void __iomem *
 io_mapping_map_atomic_wc(struct io_mapping *mapping,
-                         unsigned long offset,
-                         int slot)
+                         unsigned long offset)
 {
         return ((char __force __iomem *) mapping) + offset;
 }
 
 static inline void
-io_mapping_unmap_atomic(void __iomem *vaddr, int slot)
+io_mapping_unmap_atomic(void __iomem *vaddr)
 {
 }
 
diff --git a/mm/highmem.c b/mm/highmem.c
index 7a0aa1be4993..781e754a75ac 100644
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -42,6 +42,10 @@
 unsigned long totalhigh_pages __read_mostly;
 EXPORT_SYMBOL(totalhigh_pages);
 
+
+DEFINE_PER_CPU(int, __kmap_atomic_idx);
+EXPORT_PER_CPU_SYMBOL(__kmap_atomic_idx);
+
 unsigned int nr_free_highpages (void)
 {
         pg_data_t *pgdat;
@@ -422,61 +426,3 @@ void __init page_address_init(void)
 }
 
 #endif  /* defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL) */
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-
-void debug_kmap_atomic(enum km_type type)
-{
-        static int warn_count = 10;
-
-        if (unlikely(warn_count < 0))
-                return;
-
-        if (unlikely(in_interrupt())) {
-                if (in_nmi()) {
-                        if (type != KM_NMI && type != KM_NMI_PTE) {
-                                WARN_ON(1);
-                                warn_count--;
-                        }
-                } else if (in_irq()) {
-                        if (type != KM_IRQ0 && type != KM_IRQ1 &&
-                            type != KM_BIO_SRC_IRQ && type != KM_BIO_DST_IRQ &&
-                            type != KM_BOUNCE_READ && type != KM_IRQ_PTE) {
-                                WARN_ON(1);
-                                warn_count--;
-                        }
-                } else if (!irqs_disabled()) {  /* softirq */
-                        if (type != KM_IRQ0 && type != KM_IRQ1 &&
-                            type != KM_SOFTIRQ0 && type != KM_SOFTIRQ1 &&
-                            type != KM_SKB_SUNRPC_DATA &&
-                            type != KM_SKB_DATA_SOFTIRQ &&
-                            type != KM_BOUNCE_READ) {
-                                WARN_ON(1);
-                                warn_count--;
-                        }
-                }
-        }
-
-        if (type == KM_IRQ0 || type == KM_IRQ1 || type == KM_BOUNCE_READ ||
-                        type == KM_BIO_SRC_IRQ || type == KM_BIO_DST_IRQ ||
-                        type == KM_IRQ_PTE || type == KM_NMI ||
-                        type == KM_NMI_PTE ) {
-                if (!irqs_disabled()) {
-                        WARN_ON(1);
-                        warn_count--;
-                }
-        } else if (type == KM_SOFTIRQ0 || type == KM_SOFTIRQ1) {
-                if (irq_count() == 0 && !irqs_disabled()) {
-                        WARN_ON(1);
-                        warn_count--;
-                }
-        }
-#ifdef CONFIG_KGDB_KDB
-        if (unlikely(type == KM_KDB && atomic_read(&kgdb_active) == -1)) {
-                WARN_ON(1);
-                warn_count--;
-        }
-#endif /* CONFIG_KGDB_KDB */
-}
-
-#endif