1 files changed, 52 insertions, 26 deletions

diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c
index 2be1ec7c1b4..45aeaaca905 100644
--- a/arch/arm/mm/highmem.c
+++ b/arch/arm/mm/highmem.c
@@ -18,6 +18,21 @@
 #include <asm/tlbflush.h>
 #include "mm.h"
 
+pte_t *fixmap_page_table;
+
+static inline void set_fixmap_pte(int idx, pte_t pte)
+{
+	unsigned long vaddr = __fix_to_virt(idx);
+	set_pte_ext(fixmap_page_table + idx, pte, 0);
+	local_flush_tlb_kernel_page(vaddr);
+}
+
+static inline pte_t get_fixmap_pte(unsigned long vaddr)
+{
+	unsigned long idx = __virt_to_fix(vaddr);
+	return *(fixmap_page_table + idx);
+}
+
 void *kmap(struct page *page)
 {
 	might_sleep();
@@ -36,79 +51,92 @@ 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);
-
-	kmap = kmap_high_get(page);
+#ifdef CONFIG_DEBUG_HIGHMEM
+	/*
+	 * There is no cache coherency issue when non VIVT, so force the
+	 * dedicated kmap usage for better debugging purposes in that case.
+	 */
+	if (!cache_is_vivt())
+		kmap = NULL;
+	else
+#endif
+		kmap = kmap_high_get(page);
 	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);
+	vaddr = __fix_to_virt(idx);
 #ifdef CONFIG_DEBUG_HIGHMEM
 	/*
 	 * With debugging enabled, kunmap_atomic forces that entry to 0.
 	 * Make sure it was indeed properly unmapped.
 	 */
-	BUG_ON(!pte_none(*(TOP_PTE(vaddr))));
+	BUG_ON(!pte_none(*(fixmap_page_table + idx)));
 #endif
-	set_pte_ext(TOP_PTE(vaddr), mk_pte(page, kmap_prot), 0);
 	/*
 	 * When debugging is off, kunmap_atomic leaves the previous mapping
-	 * in place, so this TLB flush ensures the TLB is updated with the
-	 * new mapping.
+	 * in place, so the contained TLB flush ensures the TLB is updated
+	 * with the new mapping.
 	 */
-	local_flush_tlb_kernel_page(vaddr);
+	set_fixmap_pte(idx, mk_pte(page, kmap_prot));
 
 	return (void *)vaddr;
 }
 EXPORT_SYMBOL(kmap_atomic);
 
-void kunmap_atomic(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) {
-		__cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);
+		type = kmap_atomic_idx();
+		idx = type + KM_TYPE_NR * smp_processor_id();
+
+		if (cache_is_vivt())
+			__cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);
 #ifdef CONFIG_DEBUG_HIGHMEM
-		BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-		set_pte_ext(TOP_PTE(vaddr), __pte(0), 0);
-		local_flush_tlb_kernel_page(vaddr);
+		BUG_ON(vaddr != __fix_to_virt(idx));
+		set_fixmap_pte(idx, __pte(0));
 #else
 		(void) idx;  /* to kill a warning */
 #endif
+		kmap_atomic_idx_pop();
 	} else if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) {
 		/* this address was obtained through kmap_high_get() */
 		kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)]));
 	}
 	pagefault_enable();
 }
-EXPORT_SYMBOL(kunmap_atomic);
+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);
+	vaddr = __fix_to_virt(idx);
 #ifdef CONFIG_DEBUG_HIGHMEM
-	BUG_ON(!pte_none(*(TOP_PTE(vaddr))));
+	BUG_ON(!pte_none(*(fixmap_page_table + idx)));
 #endif
-	set_pte_ext(TOP_PTE(vaddr), pfn_pte(pfn, kmap_prot), 0);
-	local_flush_tlb_kernel_page(vaddr);
+	set_fixmap_pte(idx, pfn_pte(pfn, kmap_prot));
 
 	return (void *)vaddr;
 }
@@ -116,11 +144,9 @@ void *kmap_atomic_pfn(unsigned long pfn, enum km_type type)
 struct page *kmap_atomic_to_page(const void *ptr)
 {
 	unsigned long vaddr = (unsigned long)ptr;
-	pte_t *pte;
 
 	if (vaddr < FIXADDR_START)
 		return virt_to_page(ptr);
 
-	pte = TOP_PTE(vaddr);
-	return pte_page(*pte);
+	return pte_page(get_fixmap_pte(vaddr));
 }