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1#include <linux/highmem.h>
2#include <linux/module.h>
3#include <linux/swap.h> /* for totalram_pages */
4#include <linux/bootmem.h>
5
6void *kmap(struct page *page)
7{
8 might_sleep();
9 if (!PageHighMem(page))
10 return page_address(page);
11 return kmap_high(page);
12}
13EXPORT_SYMBOL(kmap);
14
15void kunmap(struct page *page)
16{
17 if (in_interrupt())
18 BUG();
19 if (!PageHighMem(page))
20 return;
21 kunmap_high(page);
22}
23EXPORT_SYMBOL(kunmap);
24
25/*
26 * kmap_atomic/kunmap_atomic is significantly faster than kmap/kunmap because
27 * no global lock is needed and because the kmap code must perform a global TLB
28 * invalidation when the kmap pool wraps.
29 *
30 * However when holding an atomic kmap it is not legal to sleep, so atomic
31 * kmaps are appropriate for short, tight code paths only.
32 */
33void *kmap_atomic_prot(struct page *page, pgprot_t prot)
34{
35 unsigned long vaddr;
36 int idx, type;
37
38 preempt_disable();
39 pagefault_disable();
40
41 if (!PageHighMem(page))
42 return page_address(page);
43
44 type = kmap_atomic_idx_push();
45 idx = type + KM_TYPE_NR*smp_processor_id();
46 vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
47 BUG_ON(!pte_none(*(kmap_pte-idx)));
48 set_pte(kmap_pte-idx, mk_pte(page, prot));
49 arch_flush_lazy_mmu_mode();
50
51 return (void *)vaddr;
52}
53EXPORT_SYMBOL(kmap_atomic_prot);
54
55void *kmap_atomic(struct page *page)
56{
57 return kmap_atomic_prot(page, kmap_prot);
58}
59EXPORT_SYMBOL(kmap_atomic);
60
61/*
62 * This is the same as kmap_atomic() but can map memory that doesn't
63 * have a struct page associated with it.
64 */
65void *kmap_atomic_pfn(unsigned long pfn)
66{
67 return kmap_atomic_prot_pfn(pfn, kmap_prot);
68}
69EXPORT_SYMBOL_GPL(kmap_atomic_pfn);
70
71void __kunmap_atomic(void *kvaddr)
72{
73 unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
74
75 if (vaddr >= __fix_to_virt(FIX_KMAP_END) &&
76 vaddr <= __fix_to_virt(FIX_KMAP_BEGIN)) {
77 int idx, type;
78
79 type = kmap_atomic_idx();
80 idx = type + KM_TYPE_NR * smp_processor_id();
81
82#ifdef CONFIG_DEBUG_HIGHMEM
83 WARN_ON_ONCE(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
84#endif
85 /*
86 * Force other mappings to Oops if they'll try to access this
87 * pte without first remap it. Keeping stale mappings around
88 * is a bad idea also, in case the page changes cacheability
89 * attributes or becomes a protected page in a hypervisor.
90 */
91 kpte_clear_flush(kmap_pte-idx, vaddr);
92 kmap_atomic_idx_pop();
93 arch_flush_lazy_mmu_mode();
94 }
95#ifdef CONFIG_DEBUG_HIGHMEM
96 else {
97 BUG_ON(vaddr < PAGE_OFFSET);
98 BUG_ON(vaddr >= (unsigned long)high_memory);
99 }
100#endif
101
102 pagefault_enable();
103 preempt_enable();
104}
105EXPORT_SYMBOL(__kunmap_atomic);
106
107void __init set_highmem_pages_init(void)
108{
109 struct zone *zone;
110 int nid;
111
112 /*
113 * Explicitly reset zone->managed_pages because set_highmem_pages_init()
114 * is invoked before free_all_bootmem()
115 */
116 reset_all_zones_managed_pages();
117 for_each_zone(zone) {
118 unsigned long zone_start_pfn, zone_end_pfn;
119
120 if (!is_highmem(zone))
121 continue;
122
123 zone_start_pfn = zone->zone_start_pfn;
124 zone_end_pfn = zone_start_pfn + zone->spanned_pages;
125
126 nid = zone_to_nid(zone);
127 printk(KERN_INFO "Initializing %s for node %d (%08lx:%08lx)\n",
128 zone->name, nid, zone_start_pfn, zone_end_pfn);
129
130 add_highpages_with_active_regions(nid, zone_start_pfn,
131 zone_end_pfn);
132 }
133}
1// SPDX-License-Identifier: GPL-2.0-only
2#include <linux/highmem.h>
3#include <linux/export.h>
4#include <linux/swap.h> /* for totalram_pages */
5#include <linux/memblock.h>
6
7void *kmap(struct page *page)
8{
9 might_sleep();
10 if (!PageHighMem(page))
11 return page_address(page);
12 return kmap_high(page);
13}
14EXPORT_SYMBOL(kmap);
15
16void kunmap(struct page *page)
17{
18 if (in_interrupt())
19 BUG();
20 if (!PageHighMem(page))
21 return;
22 kunmap_high(page);
23}
24EXPORT_SYMBOL(kunmap);
25
26/*
27 * kmap_atomic/kunmap_atomic is significantly faster than kmap/kunmap because
28 * no global lock is needed and because the kmap code must perform a global TLB
29 * invalidation when the kmap pool wraps.
30 *
31 * However when holding an atomic kmap it is not legal to sleep, so atomic
32 * kmaps are appropriate for short, tight code paths only.
33 */
34void *kmap_atomic_prot(struct page *page, pgprot_t prot)
35{
36 unsigned long vaddr;
37 int idx, type;
38
39 preempt_disable();
40 pagefault_disable();
41
42 if (!PageHighMem(page))
43 return page_address(page);
44
45 type = kmap_atomic_idx_push();
46 idx = type + KM_TYPE_NR*smp_processor_id();
47 vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
48 BUG_ON(!pte_none(*(kmap_pte-idx)));
49 set_pte(kmap_pte-idx, mk_pte(page, prot));
50 arch_flush_lazy_mmu_mode();
51
52 return (void *)vaddr;
53}
54EXPORT_SYMBOL(kmap_atomic_prot);
55
56void *kmap_atomic(struct page *page)
57{
58 return kmap_atomic_prot(page, kmap_prot);
59}
60EXPORT_SYMBOL(kmap_atomic);
61
62/*
63 * This is the same as kmap_atomic() but can map memory that doesn't
64 * have a struct page associated with it.
65 */
66void *kmap_atomic_pfn(unsigned long pfn)
67{
68 return kmap_atomic_prot_pfn(pfn, kmap_prot);
69}
70EXPORT_SYMBOL_GPL(kmap_atomic_pfn);
71
72void __kunmap_atomic(void *kvaddr)
73{
74 unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
75
76 if (vaddr >= __fix_to_virt(FIX_KMAP_END) &&
77 vaddr <= __fix_to_virt(FIX_KMAP_BEGIN)) {
78 int idx, type;
79
80 type = kmap_atomic_idx();
81 idx = type + KM_TYPE_NR * smp_processor_id();
82
83#ifdef CONFIG_DEBUG_HIGHMEM
84 WARN_ON_ONCE(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
85#endif
86 /*
87 * Force other mappings to Oops if they'll try to access this
88 * pte without first remap it. Keeping stale mappings around
89 * is a bad idea also, in case the page changes cacheability
90 * attributes or becomes a protected page in a hypervisor.
91 */
92 kpte_clear_flush(kmap_pte-idx, vaddr);
93 kmap_atomic_idx_pop();
94 arch_flush_lazy_mmu_mode();
95 }
96#ifdef CONFIG_DEBUG_HIGHMEM
97 else {
98 BUG_ON(vaddr < PAGE_OFFSET);
99 BUG_ON(vaddr >= (unsigned long)high_memory);
100 }
101#endif
102
103 pagefault_enable();
104 preempt_enable();
105}
106EXPORT_SYMBOL(__kunmap_atomic);
107
108void __init set_highmem_pages_init(void)
109{
110 struct zone *zone;
111 int nid;
112
113 /*
114 * Explicitly reset zone->managed_pages because set_highmem_pages_init()
115 * is invoked before memblock_free_all()
116 */
117 reset_all_zones_managed_pages();
118 for_each_zone(zone) {
119 unsigned long zone_start_pfn, zone_end_pfn;
120
121 if (!is_highmem(zone))
122 continue;
123
124 zone_start_pfn = zone->zone_start_pfn;
125 zone_end_pfn = zone_start_pfn + zone->spanned_pages;
126
127 nid = zone_to_nid(zone);
128 printk(KERN_INFO "Initializing %s for node %d (%08lx:%08lx)\n",
129 zone->name, nid, zone_start_pfn, zone_end_pfn);
130
131 add_highpages_with_active_regions(nid, zone_start_pfn,
132 zone_end_pfn);
133 }
134}