xref: /openbmc/linux/arch/arm64/include/asm/tlb.h (revision b4a6aaea)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Based on arch/arm/include/asm/tlb.h
4  *
5  * Copyright (C) 2002 Russell King
6  * Copyright (C) 2012 ARM Ltd.
7  */
8 #ifndef __ASM_TLB_H
9 #define __ASM_TLB_H
10 
11 #include <linux/pagemap.h>
12 #include <linux/swap.h>
13 
14 static inline void __tlb_remove_table(void *_table)
15 {
16 	free_page_and_swap_cache((struct page *)_table);
17 }
18 
19 #define tlb_flush tlb_flush
20 static void tlb_flush(struct mmu_gather *tlb);
21 
22 #include <asm-generic/tlb.h>
23 
24 /*
25  * get the tlbi levels in arm64.  Default value is 0 if more than one
26  * of cleared_* is set or neither is set.
27  * Arm64 doesn't support p4ds now.
28  */
29 static inline int tlb_get_level(struct mmu_gather *tlb)
30 {
31 	/* The TTL field is only valid for the leaf entry. */
32 	if (tlb->freed_tables)
33 		return 0;
34 
35 	if (tlb->cleared_ptes && !(tlb->cleared_pmds ||
36 				   tlb->cleared_puds ||
37 				   tlb->cleared_p4ds))
38 		return 3;
39 
40 	if (tlb->cleared_pmds && !(tlb->cleared_ptes ||
41 				   tlb->cleared_puds ||
42 				   tlb->cleared_p4ds))
43 		return 2;
44 
45 	if (tlb->cleared_puds && !(tlb->cleared_ptes ||
46 				   tlb->cleared_pmds ||
47 				   tlb->cleared_p4ds))
48 		return 1;
49 
50 	return 0;
51 }
52 
53 static inline void tlb_flush(struct mmu_gather *tlb)
54 {
55 	struct vm_area_struct vma = TLB_FLUSH_VMA(tlb->mm, 0);
56 	bool last_level = !tlb->freed_tables;
57 	unsigned long stride = tlb_get_unmap_size(tlb);
58 	int tlb_level = tlb_get_level(tlb);
59 
60 	/*
61 	 * If we're tearing down the address space then we only care about
62 	 * invalidating the walk-cache, since the ASID allocator won't
63 	 * reallocate our ASID without invalidating the entire TLB.
64 	 */
65 	if (tlb->fullmm) {
66 		if (!last_level)
67 			flush_tlb_mm(tlb->mm);
68 		return;
69 	}
70 
71 	__flush_tlb_range(&vma, tlb->start, tlb->end, stride,
72 			  last_level, tlb_level);
73 }
74 
75 static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte,
76 				  unsigned long addr)
77 {
78 	pgtable_pte_page_dtor(pte);
79 	tlb_remove_table(tlb, pte);
80 }
81 
82 #if CONFIG_PGTABLE_LEVELS > 2
83 static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp,
84 				  unsigned long addr)
85 {
86 	struct page *page = virt_to_page(pmdp);
87 
88 	pgtable_pmd_page_dtor(page);
89 	tlb_remove_table(tlb, page);
90 }
91 #endif
92 
93 #if CONFIG_PGTABLE_LEVELS > 3
94 static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pudp,
95 				  unsigned long addr)
96 {
97 	tlb_remove_table(tlb, virt_to_page(pudp));
98 }
99 #endif
100 
101 #endif
102