aboutsummaryrefslogtreecommitdiffstats
path: root/arch/i386/mm/highmem.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/i386/mm/highmem.c')
-rw-r--r--arch/i386/mm/highmem.c26
1 files changed, 11 insertions, 15 deletions
diff --git a/arch/i386/mm/highmem.c b/arch/i386/mm/highmem.c
index f9f647cdbc7b..e0fa6cb655a8 100644
--- a/arch/i386/mm/highmem.c
+++ b/arch/i386/mm/highmem.c
@@ -32,7 +32,7 @@ void *kmap_atomic(struct page *page, enum km_type type)
32 unsigned long vaddr; 32 unsigned long vaddr;
33 33
34 /* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */ 34 /* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
35 inc_preempt_count(); 35 pagefault_disable();
36 if (!PageHighMem(page)) 36 if (!PageHighMem(page))
37 return page_address(page); 37 return page_address(page);
38 38
@@ -50,26 +50,22 @@ void kunmap_atomic(void *kvaddr, enum km_type type)
50 unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK; 50 unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
51 enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id(); 51 enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id();
52 52
53#ifdef CONFIG_DEBUG_HIGHMEM
54 if (vaddr >= PAGE_OFFSET && vaddr < (unsigned long)high_memory) {
55 dec_preempt_count();
56 preempt_check_resched();
57 return;
58 }
59
60 if (vaddr != __fix_to_virt(FIX_KMAP_BEGIN+idx))
61 BUG();
62#endif
63 /* 53 /*
64 * Force other mappings to Oops if they'll try to access this pte 54 * Force other mappings to Oops if they'll try to access this pte
65 * without first remap it. Keeping stale mappings around is a bad idea 55 * without first remap it. Keeping stale mappings around is a bad idea
66 * also, in case the page changes cacheability attributes or becomes 56 * also, in case the page changes cacheability attributes or becomes
67 * a protected page in a hypervisor. 57 * a protected page in a hypervisor.
68 */ 58 */
69 kpte_clear_flush(kmap_pte-idx, vaddr); 59 if (vaddr == __fix_to_virt(FIX_KMAP_BEGIN+idx))
60 kpte_clear_flush(kmap_pte-idx, vaddr);
61 else {
62#ifdef CONFIG_DEBUG_HIGHMEM
63 BUG_ON(vaddr < PAGE_OFFSET);
64 BUG_ON(vaddr >= (unsigned long)high_memory);
65#endif
66 }
70 67
71 dec_preempt_count(); 68 pagefault_enable();
72 preempt_check_resched();
73} 69}
74 70
75/* This is the same as kmap_atomic() but can map memory that doesn't 71/* This is the same as kmap_atomic() but can map memory that doesn't
@@ -80,7 +76,7 @@ void *kmap_atomic_pfn(unsigned long pfn, enum km_type type)
80 enum fixed_addresses idx; 76 enum fixed_addresses idx;
81 unsigned long vaddr; 77 unsigned long vaddr;
82 78
83 inc_preempt_count(); 79 pagefault_disable();
84 80
85 idx = type + KM_TYPE_NR*smp_processor_id(); 81 idx = type + KM_TYPE_NR*smp_processor_id();
86 vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); 82 vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);