1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun #include <linux/highmem.h>
3*4882a593Smuzhiyun #include <linux/export.h>
4*4882a593Smuzhiyun #include <linux/swap.h> /* for totalram_pages */
5*4882a593Smuzhiyun #include <linux/memblock.h>
6*4882a593Smuzhiyun
kmap_atomic_high_prot(struct page * page,pgprot_t prot)7*4882a593Smuzhiyun void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
8*4882a593Smuzhiyun {
9*4882a593Smuzhiyun unsigned long vaddr;
10*4882a593Smuzhiyun int idx, type;
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun type = kmap_atomic_idx_push();
13*4882a593Smuzhiyun idx = type + KM_TYPE_NR*smp_processor_id();
14*4882a593Smuzhiyun vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
15*4882a593Smuzhiyun BUG_ON(!pte_none(*(kmap_pte-idx)));
16*4882a593Smuzhiyun set_pte(kmap_pte-idx, mk_pte(page, prot));
17*4882a593Smuzhiyun arch_flush_lazy_mmu_mode();
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun return (void *)vaddr;
20*4882a593Smuzhiyun }
21*4882a593Smuzhiyun EXPORT_SYMBOL(kmap_atomic_high_prot);
22*4882a593Smuzhiyun
23*4882a593Smuzhiyun /*
24*4882a593Smuzhiyun * This is the same as kmap_atomic() but can map memory that doesn't
25*4882a593Smuzhiyun * have a struct page associated with it.
26*4882a593Smuzhiyun */
kmap_atomic_pfn(unsigned long pfn)27*4882a593Smuzhiyun void *kmap_atomic_pfn(unsigned long pfn)
28*4882a593Smuzhiyun {
29*4882a593Smuzhiyun return kmap_atomic_prot_pfn(pfn, kmap_prot);
30*4882a593Smuzhiyun }
31*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(kmap_atomic_pfn);
32*4882a593Smuzhiyun
kunmap_atomic_high(void * kvaddr)33*4882a593Smuzhiyun void kunmap_atomic_high(void *kvaddr)
34*4882a593Smuzhiyun {
35*4882a593Smuzhiyun unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
36*4882a593Smuzhiyun
37*4882a593Smuzhiyun if (vaddr >= __fix_to_virt(FIX_KMAP_END) &&
38*4882a593Smuzhiyun vaddr <= __fix_to_virt(FIX_KMAP_BEGIN)) {
39*4882a593Smuzhiyun int idx, type;
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun type = kmap_atomic_idx();
42*4882a593Smuzhiyun idx = type + KM_TYPE_NR * smp_processor_id();
43*4882a593Smuzhiyun
44*4882a593Smuzhiyun #ifdef CONFIG_DEBUG_HIGHMEM
45*4882a593Smuzhiyun WARN_ON_ONCE(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
46*4882a593Smuzhiyun #endif
47*4882a593Smuzhiyun /*
48*4882a593Smuzhiyun * Force other mappings to Oops if they'll try to access this
49*4882a593Smuzhiyun * pte without first remap it. Keeping stale mappings around
50*4882a593Smuzhiyun * is a bad idea also, in case the page changes cacheability
51*4882a593Smuzhiyun * attributes or becomes a protected page in a hypervisor.
52*4882a593Smuzhiyun */
53*4882a593Smuzhiyun kpte_clear_flush(kmap_pte-idx, vaddr);
54*4882a593Smuzhiyun kmap_atomic_idx_pop();
55*4882a593Smuzhiyun arch_flush_lazy_mmu_mode();
56*4882a593Smuzhiyun }
57*4882a593Smuzhiyun #ifdef CONFIG_DEBUG_HIGHMEM
58*4882a593Smuzhiyun else {
59*4882a593Smuzhiyun BUG_ON(vaddr < PAGE_OFFSET);
60*4882a593Smuzhiyun BUG_ON(vaddr >= (unsigned long)high_memory);
61*4882a593Smuzhiyun }
62*4882a593Smuzhiyun #endif
63*4882a593Smuzhiyun }
64*4882a593Smuzhiyun EXPORT_SYMBOL(kunmap_atomic_high);
65*4882a593Smuzhiyun
set_highmem_pages_init(void)66*4882a593Smuzhiyun void __init set_highmem_pages_init(void)
67*4882a593Smuzhiyun {
68*4882a593Smuzhiyun struct zone *zone;
69*4882a593Smuzhiyun int nid;
70*4882a593Smuzhiyun
71*4882a593Smuzhiyun /*
72*4882a593Smuzhiyun * Explicitly reset zone->managed_pages because set_highmem_pages_init()
73*4882a593Smuzhiyun * is invoked before memblock_free_all()
74*4882a593Smuzhiyun */
75*4882a593Smuzhiyun reset_all_zones_managed_pages();
76*4882a593Smuzhiyun for_each_zone(zone) {
77*4882a593Smuzhiyun unsigned long zone_start_pfn, zone_end_pfn;
78*4882a593Smuzhiyun
79*4882a593Smuzhiyun if (!is_highmem(zone))
80*4882a593Smuzhiyun continue;
81*4882a593Smuzhiyun
82*4882a593Smuzhiyun zone_start_pfn = zone->zone_start_pfn;
83*4882a593Smuzhiyun zone_end_pfn = zone_start_pfn + zone->spanned_pages;
84*4882a593Smuzhiyun
85*4882a593Smuzhiyun nid = zone_to_nid(zone);
86*4882a593Smuzhiyun printk(KERN_INFO "Initializing %s for node %d (%08lx:%08lx)\n",
87*4882a593Smuzhiyun zone->name, nid, zone_start_pfn, zone_end_pfn);
88*4882a593Smuzhiyun
89*4882a593Smuzhiyun add_highpages_with_active_regions(nid, zone_start_pfn,
90*4882a593Smuzhiyun zone_end_pfn);
91*4882a593Smuzhiyun }
92*4882a593Smuzhiyun }
93