1 // SPDX-License-Identifier: GPL-2.0
2
3 #include <linux/mm.h>
4 #include <linux/smp.h>
5 #include <linux/sched.h>
6 #include <asm/sbi.h>
7 #include <asm/mmu_context.h>
8
9 /*
10 * Flush entire TLB if number of entries to be flushed is greater
11 * than the threshold below.
12 */
13 static unsigned long tlb_flush_all_threshold __read_mostly = 64;
14
local_flush_tlb_range_threshold_asid(unsigned long start,unsigned long size,unsigned long stride,unsigned long asid)15 static void local_flush_tlb_range_threshold_asid(unsigned long start,
16 unsigned long size,
17 unsigned long stride,
18 unsigned long asid)
19 {
20 unsigned long nr_ptes_in_range = DIV_ROUND_UP(size, stride);
21 int i;
22
23 if (nr_ptes_in_range > tlb_flush_all_threshold) {
24 local_flush_tlb_all_asid(asid);
25 return;
26 }
27
28 for (i = 0; i < nr_ptes_in_range; ++i) {
29 local_flush_tlb_page_asid(start, asid);
30 start += stride;
31 }
32 }
33
local_flush_tlb_range_asid(unsigned long start,unsigned long size,unsigned long stride,unsigned long asid)34 static inline void local_flush_tlb_range_asid(unsigned long start,
35 unsigned long size, unsigned long stride, unsigned long asid)
36 {
37 if (size <= stride)
38 local_flush_tlb_page_asid(start, asid);
39 else if (size == FLUSH_TLB_MAX_SIZE)
40 local_flush_tlb_all_asid(asid);
41 else
42 local_flush_tlb_range_threshold_asid(start, size, stride, asid);
43 }
44
45 /* Flush a range of kernel pages without broadcasting */
local_flush_tlb_kernel_range(unsigned long start,unsigned long end)46 void local_flush_tlb_kernel_range(unsigned long start, unsigned long end)
47 {
48 local_flush_tlb_range_asid(start, end - start, PAGE_SIZE, FLUSH_TLB_NO_ASID);
49 }
50
__ipi_flush_tlb_all(void * info)51 static void __ipi_flush_tlb_all(void *info)
52 {
53 local_flush_tlb_all();
54 }
55
flush_tlb_all(void)56 void flush_tlb_all(void)
57 {
58 if (riscv_use_ipi_for_rfence())
59 on_each_cpu(__ipi_flush_tlb_all, NULL, 1);
60 else
61 sbi_remote_sfence_vma_asid(NULL, 0, FLUSH_TLB_MAX_SIZE, FLUSH_TLB_NO_ASID);
62 }
63
64 struct flush_tlb_range_data {
65 unsigned long asid;
66 unsigned long start;
67 unsigned long size;
68 unsigned long stride;
69 };
70
__ipi_flush_tlb_range_asid(void * info)71 static void __ipi_flush_tlb_range_asid(void *info)
72 {
73 struct flush_tlb_range_data *d = info;
74
75 local_flush_tlb_range_asid(d->start, d->size, d->stride, d->asid);
76 }
77
__flush_tlb_range(struct mm_struct * mm,unsigned long start,unsigned long size,unsigned long stride)78 static void __flush_tlb_range(struct mm_struct *mm, unsigned long start,
79 unsigned long size, unsigned long stride)
80 {
81 struct flush_tlb_range_data ftd;
82 const struct cpumask *cmask;
83 unsigned long asid = FLUSH_TLB_NO_ASID;
84 bool broadcast;
85
86 if (mm) {
87 unsigned int cpuid;
88
89 cmask = mm_cpumask(mm);
90 if (cpumask_empty(cmask))
91 return;
92
93 cpuid = get_cpu();
94 /* check if the tlbflush needs to be sent to other CPUs */
95 broadcast = cpumask_any_but(cmask, cpuid) < nr_cpu_ids;
96
97 if (static_branch_unlikely(&use_asid_allocator))
98 asid = atomic_long_read(&mm->context.id) & asid_mask;
99 } else {
100 cmask = cpu_online_mask;
101 broadcast = true;
102 }
103
104 if (broadcast) {
105 if (riscv_use_ipi_for_rfence()) {
106 ftd.asid = asid;
107 ftd.start = start;
108 ftd.size = size;
109 ftd.stride = stride;
110 on_each_cpu_mask(cmask,
111 __ipi_flush_tlb_range_asid,
112 &ftd, 1);
113 } else
114 sbi_remote_sfence_vma_asid(cmask,
115 start, size, asid);
116 } else {
117 local_flush_tlb_range_asid(start, size, stride, asid);
118 }
119
120 if (mm)
121 put_cpu();
122 }
123
flush_tlb_mm(struct mm_struct * mm)124 void flush_tlb_mm(struct mm_struct *mm)
125 {
126 __flush_tlb_range(mm, 0, FLUSH_TLB_MAX_SIZE, PAGE_SIZE);
127 }
128
flush_tlb_mm_range(struct mm_struct * mm,unsigned long start,unsigned long end,unsigned int page_size)129 void flush_tlb_mm_range(struct mm_struct *mm,
130 unsigned long start, unsigned long end,
131 unsigned int page_size)
132 {
133 __flush_tlb_range(mm, start, end - start, page_size);
134 }
135
flush_tlb_page(struct vm_area_struct * vma,unsigned long addr)136 void flush_tlb_page(struct vm_area_struct *vma, unsigned long addr)
137 {
138 __flush_tlb_range(vma->vm_mm, addr, PAGE_SIZE, PAGE_SIZE);
139 }
140
flush_tlb_range(struct vm_area_struct * vma,unsigned long start,unsigned long end)141 void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
142 unsigned long end)
143 {
144 __flush_tlb_range(vma->vm_mm, start, end - start, PAGE_SIZE);
145 }
146
flush_tlb_kernel_range(unsigned long start,unsigned long end)147 void flush_tlb_kernel_range(unsigned long start, unsigned long end)
148 {
149 __flush_tlb_range(NULL, start, end - start, PAGE_SIZE);
150 }
151
152 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
flush_pmd_tlb_range(struct vm_area_struct * vma,unsigned long start,unsigned long end)153 void flush_pmd_tlb_range(struct vm_area_struct *vma, unsigned long start,
154 unsigned long end)
155 {
156 __flush_tlb_range(vma->vm_mm, start, end - start, PMD_SIZE);
157 }
158 #endif
159