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>

20 files changed, 294 insertions, 257 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();
 }