1// SPDX-License-Identifier: GPL-2.0
 2#include <linux/compiler.h>
 3#include <linux/init.h>
 4#include <linux/export.h>
 5#include <linux/highmem.h>
 6#include <linux/sched.h>
 7#include <linux/smp.h>
 8#include <asm/fixmap.h>
 9#include <asm/tlbflush.h>
10
 
 
11unsigned long highstart_pfn, highend_pfn;
12
13void kmap_flush_tlb(unsigned long addr)
14{
15	flush_tlb_one(addr);
16}
17EXPORT_SYMBOL(kmap_flush_tlb);

 1// SPDX-License-Identifier: GPL-2.0
 2#include <linux/compiler.h>
 3#include <linux/init.h>
 4#include <linux/export.h>
 5#include <linux/highmem.h>
 6#include <linux/sched.h>
 7#include <linux/smp.h>
 8#include <asm/fixmap.h>
 9#include <asm/tlbflush.h>
10
11static pte_t *kmap_pte;
12
13unsigned long highstart_pfn, highend_pfn;
14
15void kmap_flush_tlb(unsigned long addr)
16{
17	flush_tlb_one(addr);
18}
19EXPORT_SYMBOL(kmap_flush_tlb);
20
21void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
22{
23	unsigned long vaddr;
24	int idx, type;
25
26	type = kmap_atomic_idx_push();
27	idx = type + KM_TYPE_NR*smp_processor_id();
28	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
29#ifdef CONFIG_DEBUG_HIGHMEM
30	BUG_ON(!pte_none(*(kmap_pte - idx)));
31#endif
32	set_pte(kmap_pte-idx, mk_pte(page, prot));
33	local_flush_tlb_one((unsigned long)vaddr);
34
35	return (void*) vaddr;
36}
37EXPORT_SYMBOL(kmap_atomic_high_prot);
38
39void kunmap_atomic_high(void *kvaddr)
40{
41	unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
42	int type __maybe_unused;
43
44	if (vaddr < FIXADDR_START)
45		return;
46
47	type = kmap_atomic_idx();
48#ifdef CONFIG_DEBUG_HIGHMEM
49	{
50		int idx = type + KM_TYPE_NR * smp_processor_id();
51
52		BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
53
54		/*
55		 * force other mappings to Oops if they'll try to access
56		 * this pte without first remap it
57		 */
58		pte_clear(&init_mm, vaddr, kmap_pte-idx);
59		local_flush_tlb_one(vaddr);
60	}
61#endif
62	kmap_atomic_idx_pop();
63}
64EXPORT_SYMBOL(kunmap_atomic_high);
65
66/*
67 * This is the same as kmap_atomic() but can map memory that doesn't
68 * have a struct page associated with it.
69 */
70void *kmap_atomic_pfn(unsigned long pfn)
71{
72	unsigned long vaddr;
73	int idx, type;
74
75	preempt_disable();
76	pagefault_disable();
77
78	type = kmap_atomic_idx_push();
79	idx = type + KM_TYPE_NR*smp_processor_id();
80	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
81	set_pte(kmap_pte-idx, pfn_pte(pfn, PAGE_KERNEL));
82	flush_tlb_one(vaddr);
83
84	return (void*) vaddr;
85}
86
87void __init kmap_init(void)
88{
89	unsigned long kmap_vstart;
90
91	/* cache the first kmap pte */
92	kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
93	kmap_pte = virt_to_kpte(kmap_vstart);
94}