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1// SPDX-License-Identifier: GPL-2.0
2/* arch/sparc64/mm/tlb.c
3 *
4 * Copyright (C) 2004 David S. Miller <davem@redhat.com>
5 */
6
7#include <linux/kernel.h>
8#include <linux/percpu.h>
9#include <linux/mm.h>
10#include <linux/swap.h>
11#include <linux/preempt.h>
12
13#include <asm/pgtable.h>
14#include <asm/pgalloc.h>
15#include <asm/tlbflush.h>
16#include <asm/cacheflush.h>
17#include <asm/mmu_context.h>
18#include <asm/tlb.h>
19
20/* Heavily inspired by the ppc64 code. */
21
22static DEFINE_PER_CPU(struct tlb_batch, tlb_batch);
23
24void flush_tlb_pending(void)
25{
26 struct tlb_batch *tb = &get_cpu_var(tlb_batch);
27 struct mm_struct *mm = tb->mm;
28
29 if (!tb->tlb_nr)
30 goto out;
31
32 flush_tsb_user(tb);
33
34 if (CTX_VALID(mm->context)) {
35 if (tb->tlb_nr == 1) {
36 global_flush_tlb_page(mm, tb->vaddrs[0]);
37 } else {
38#ifdef CONFIG_SMP
39 smp_flush_tlb_pending(tb->mm, tb->tlb_nr,
40 &tb->vaddrs[0]);
41#else
42 __flush_tlb_pending(CTX_HWBITS(tb->mm->context),
43 tb->tlb_nr, &tb->vaddrs[0]);
44#endif
45 }
46 }
47
48 tb->tlb_nr = 0;
49
50out:
51 put_cpu_var(tlb_batch);
52}
53
54void arch_enter_lazy_mmu_mode(void)
55{
56 struct tlb_batch *tb = this_cpu_ptr(&tlb_batch);
57
58 tb->active = 1;
59}
60
61void arch_leave_lazy_mmu_mode(void)
62{
63 struct tlb_batch *tb = this_cpu_ptr(&tlb_batch);
64
65 if (tb->tlb_nr)
66 flush_tlb_pending();
67 tb->active = 0;
68}
69
70static void tlb_batch_add_one(struct mm_struct *mm, unsigned long vaddr,
71 bool exec, unsigned int hugepage_shift)
72{
73 struct tlb_batch *tb = &get_cpu_var(tlb_batch);
74 unsigned long nr;
75
76 vaddr &= PAGE_MASK;
77 if (exec)
78 vaddr |= 0x1UL;
79
80 nr = tb->tlb_nr;
81
82 if (unlikely(nr != 0 && mm != tb->mm)) {
83 flush_tlb_pending();
84 nr = 0;
85 }
86
87 if (!tb->active) {
88 flush_tsb_user_page(mm, vaddr, hugepage_shift);
89 global_flush_tlb_page(mm, vaddr);
90 goto out;
91 }
92
93 if (nr == 0) {
94 tb->mm = mm;
95 tb->hugepage_shift = hugepage_shift;
96 }
97
98 if (tb->hugepage_shift != hugepage_shift) {
99 flush_tlb_pending();
100 tb->hugepage_shift = hugepage_shift;
101 nr = 0;
102 }
103
104 tb->vaddrs[nr] = vaddr;
105 tb->tlb_nr = ++nr;
106 if (nr >= TLB_BATCH_NR)
107 flush_tlb_pending();
108
109out:
110 put_cpu_var(tlb_batch);
111}
112
113void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr,
114 pte_t *ptep, pte_t orig, int fullmm,
115 unsigned int hugepage_shift)
116{
117 if (tlb_type != hypervisor &&
118 pte_dirty(orig)) {
119 unsigned long paddr, pfn = pte_pfn(orig);
120 struct address_space *mapping;
121 struct page *page;
122
123 if (!pfn_valid(pfn))
124 goto no_cache_flush;
125
126 page = pfn_to_page(pfn);
127 if (PageReserved(page))
128 goto no_cache_flush;
129
130 /* A real file page? */
131 mapping = page_mapping_file(page);
132 if (!mapping)
133 goto no_cache_flush;
134
135 paddr = (unsigned long) page_address(page);
136 if ((paddr ^ vaddr) & (1 << 13))
137 flush_dcache_page_all(mm, page);
138 }
139
140no_cache_flush:
141 if (!fullmm)
142 tlb_batch_add_one(mm, vaddr, pte_exec(orig), hugepage_shift);
143}
144
145#ifdef CONFIG_TRANSPARENT_HUGEPAGE
146static void tlb_batch_pmd_scan(struct mm_struct *mm, unsigned long vaddr,
147 pmd_t pmd)
148{
149 unsigned long end;
150 pte_t *pte;
151
152 pte = pte_offset_map(&pmd, vaddr);
153 end = vaddr + HPAGE_SIZE;
154 while (vaddr < end) {
155 if (pte_val(*pte) & _PAGE_VALID) {
156 bool exec = pte_exec(*pte);
157
158 tlb_batch_add_one(mm, vaddr, exec, PAGE_SHIFT);
159 }
160 pte++;
161 vaddr += PAGE_SIZE;
162 }
163 pte_unmap(pte);
164}
165
166
167static void __set_pmd_acct(struct mm_struct *mm, unsigned long addr,
168 pmd_t orig, pmd_t pmd)
169{
170 if (mm == &init_mm)
171 return;
172
173 if ((pmd_val(pmd) ^ pmd_val(orig)) & _PAGE_PMD_HUGE) {
174 /*
175 * Note that this routine only sets pmds for THP pages.
176 * Hugetlb pages are handled elsewhere. We need to check
177 * for huge zero page. Huge zero pages are like hugetlb
178 * pages in that there is no RSS, but there is the need
179 * for TSB entries. So, huge zero page counts go into
180 * hugetlb_pte_count.
181 */
182 if (pmd_val(pmd) & _PAGE_PMD_HUGE) {
183 if (is_huge_zero_page(pmd_page(pmd)))
184 mm->context.hugetlb_pte_count++;
185 else
186 mm->context.thp_pte_count++;
187 } else {
188 if (is_huge_zero_page(pmd_page(orig)))
189 mm->context.hugetlb_pte_count--;
190 else
191 mm->context.thp_pte_count--;
192 }
193
194 /* Do not try to allocate the TSB hash table if we
195 * don't have one already. We have various locks held
196 * and thus we'll end up doing a GFP_KERNEL allocation
197 * in an atomic context.
198 *
199 * Instead, we let the first TLB miss on a hugepage
200 * take care of this.
201 */
202 }
203
204 if (!pmd_none(orig)) {
205 addr &= HPAGE_MASK;
206 if (pmd_trans_huge(orig)) {
207 pte_t orig_pte = __pte(pmd_val(orig));
208 bool exec = pte_exec(orig_pte);
209
210 tlb_batch_add_one(mm, addr, exec, REAL_HPAGE_SHIFT);
211 tlb_batch_add_one(mm, addr + REAL_HPAGE_SIZE, exec,
212 REAL_HPAGE_SHIFT);
213 } else {
214 tlb_batch_pmd_scan(mm, addr, orig);
215 }
216 }
217}
218
219void set_pmd_at(struct mm_struct *mm, unsigned long addr,
220 pmd_t *pmdp, pmd_t pmd)
221{
222 pmd_t orig = *pmdp;
223
224 *pmdp = pmd;
225 __set_pmd_acct(mm, addr, orig, pmd);
226}
227
228static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
229 unsigned long address, pmd_t *pmdp, pmd_t pmd)
230{
231 pmd_t old;
232
233 do {
234 old = *pmdp;
235 } while (cmpxchg64(&pmdp->pmd, old.pmd, pmd.pmd) != old.pmd);
236 __set_pmd_acct(vma->vm_mm, address, old, pmd);
237
238 return old;
239}
240
241/*
242 * This routine is only called when splitting a THP
243 */
244pmd_t pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
245 pmd_t *pmdp)
246{
247 pmd_t old, entry;
248
249 entry = __pmd(pmd_val(*pmdp) & ~_PAGE_VALID);
250 old = pmdp_establish(vma, address, pmdp, entry);
251 flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
252
253 /*
254 * set_pmd_at() will not be called in a way to decrement
255 * thp_pte_count when splitting a THP, so do it now.
256 * Sanity check pmd before doing the actual decrement.
257 */
258 if ((pmd_val(entry) & _PAGE_PMD_HUGE) &&
259 !is_huge_zero_page(pmd_page(entry)))
260 (vma->vm_mm)->context.thp_pte_count--;
261
262 return old;
263}
264
265void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
266 pgtable_t pgtable)
267{
268 struct list_head *lh = (struct list_head *) pgtable;
269
270 assert_spin_locked(&mm->page_table_lock);
271
272 /* FIFO */
273 if (!pmd_huge_pte(mm, pmdp))
274 INIT_LIST_HEAD(lh);
275 else
276 list_add(lh, (struct list_head *) pmd_huge_pte(mm, pmdp));
277 pmd_huge_pte(mm, pmdp) = pgtable;
278}
279
280pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
281{
282 struct list_head *lh;
283 pgtable_t pgtable;
284
285 assert_spin_locked(&mm->page_table_lock);
286
287 /* FIFO */
288 pgtable = pmd_huge_pte(mm, pmdp);
289 lh = (struct list_head *) pgtable;
290 if (list_empty(lh))
291 pmd_huge_pte(mm, pmdp) = NULL;
292 else {
293 pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next;
294 list_del(lh);
295 }
296 pte_val(pgtable[0]) = 0;
297 pte_val(pgtable[1]) = 0;
298
299 return pgtable;
300}
301#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1/* arch/sparc64/mm/tlb.c
2 *
3 * Copyright (C) 2004 David S. Miller <davem@redhat.com>
4 */
5
6#include <linux/kernel.h>
7#include <linux/percpu.h>
8#include <linux/mm.h>
9#include <linux/swap.h>
10#include <linux/preempt.h>
11
12#include <asm/pgtable.h>
13#include <asm/pgalloc.h>
14#include <asm/tlbflush.h>
15#include <asm/cacheflush.h>
16#include <asm/mmu_context.h>
17#include <asm/tlb.h>
18
19/* Heavily inspired by the ppc64 code. */
20
21static DEFINE_PER_CPU(struct tlb_batch, tlb_batch);
22
23void flush_tlb_pending(void)
24{
25 struct tlb_batch *tb = &get_cpu_var(tlb_batch);
26 struct mm_struct *mm = tb->mm;
27
28 if (!tb->tlb_nr)
29 goto out;
30
31 flush_tsb_user(tb);
32
33 if (CTX_VALID(mm->context)) {
34 if (tb->tlb_nr == 1) {
35 global_flush_tlb_page(mm, tb->vaddrs[0]);
36 } else {
37#ifdef CONFIG_SMP
38 smp_flush_tlb_pending(tb->mm, tb->tlb_nr,
39 &tb->vaddrs[0]);
40#else
41 __flush_tlb_pending(CTX_HWBITS(tb->mm->context),
42 tb->tlb_nr, &tb->vaddrs[0]);
43#endif
44 }
45 }
46
47 tb->tlb_nr = 0;
48
49out:
50 put_cpu_var(tlb_batch);
51}
52
53void arch_enter_lazy_mmu_mode(void)
54{
55 struct tlb_batch *tb = this_cpu_ptr(&tlb_batch);
56
57 tb->active = 1;
58}
59
60void arch_leave_lazy_mmu_mode(void)
61{
62 struct tlb_batch *tb = this_cpu_ptr(&tlb_batch);
63
64 if (tb->tlb_nr)
65 flush_tlb_pending();
66 tb->active = 0;
67}
68
69static void tlb_batch_add_one(struct mm_struct *mm, unsigned long vaddr,
70 bool exec, bool huge)
71{
72 struct tlb_batch *tb = &get_cpu_var(tlb_batch);
73 unsigned long nr;
74
75 vaddr &= PAGE_MASK;
76 if (exec)
77 vaddr |= 0x1UL;
78
79 nr = tb->tlb_nr;
80
81 if (unlikely(nr != 0 && mm != tb->mm)) {
82 flush_tlb_pending();
83 nr = 0;
84 }
85
86 if (!tb->active) {
87 flush_tsb_user_page(mm, vaddr, huge);
88 global_flush_tlb_page(mm, vaddr);
89 goto out;
90 }
91
92 if (nr == 0) {
93 tb->mm = mm;
94 tb->huge = huge;
95 }
96
97 if (tb->huge != huge) {
98 flush_tlb_pending();
99 tb->huge = huge;
100 nr = 0;
101 }
102
103 tb->vaddrs[nr] = vaddr;
104 tb->tlb_nr = ++nr;
105 if (nr >= TLB_BATCH_NR)
106 flush_tlb_pending();
107
108out:
109 put_cpu_var(tlb_batch);
110}
111
112void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr,
113 pte_t *ptep, pte_t orig, int fullmm)
114{
115 bool huge = is_hugetlb_pte(orig);
116
117 if (tlb_type != hypervisor &&
118 pte_dirty(orig)) {
119 unsigned long paddr, pfn = pte_pfn(orig);
120 struct address_space *mapping;
121 struct page *page;
122
123 if (!pfn_valid(pfn))
124 goto no_cache_flush;
125
126 page = pfn_to_page(pfn);
127 if (PageReserved(page))
128 goto no_cache_flush;
129
130 /* A real file page? */
131 mapping = page_mapping(page);
132 if (!mapping)
133 goto no_cache_flush;
134
135 paddr = (unsigned long) page_address(page);
136 if ((paddr ^ vaddr) & (1 << 13))
137 flush_dcache_page_all(mm, page);
138 }
139
140no_cache_flush:
141 if (!fullmm)
142 tlb_batch_add_one(mm, vaddr, pte_exec(orig), huge);
143}
144
145#ifdef CONFIG_TRANSPARENT_HUGEPAGE
146static void tlb_batch_pmd_scan(struct mm_struct *mm, unsigned long vaddr,
147 pmd_t pmd)
148{
149 unsigned long end;
150 pte_t *pte;
151
152 pte = pte_offset_map(&pmd, vaddr);
153 end = vaddr + HPAGE_SIZE;
154 while (vaddr < end) {
155 if (pte_val(*pte) & _PAGE_VALID) {
156 bool exec = pte_exec(*pte);
157
158 tlb_batch_add_one(mm, vaddr, exec, false);
159 }
160 pte++;
161 vaddr += PAGE_SIZE;
162 }
163 pte_unmap(pte);
164}
165
166void set_pmd_at(struct mm_struct *mm, unsigned long addr,
167 pmd_t *pmdp, pmd_t pmd)
168{
169 pmd_t orig = *pmdp;
170
171 *pmdp = pmd;
172
173 if (mm == &init_mm)
174 return;
175
176 if ((pmd_val(pmd) ^ pmd_val(orig)) & _PAGE_PMD_HUGE) {
177 /*
178 * Note that this routine only sets pmds for THP pages.
179 * Hugetlb pages are handled elsewhere. We need to check
180 * for huge zero page. Huge zero pages are like hugetlb
181 * pages in that there is no RSS, but there is the need
182 * for TSB entries. So, huge zero page counts go into
183 * hugetlb_pte_count.
184 */
185 if (pmd_val(pmd) & _PAGE_PMD_HUGE) {
186 if (is_huge_zero_page(pmd_page(pmd)))
187 mm->context.hugetlb_pte_count++;
188 else
189 mm->context.thp_pte_count++;
190 } else {
191 if (is_huge_zero_page(pmd_page(orig)))
192 mm->context.hugetlb_pte_count--;
193 else
194 mm->context.thp_pte_count--;
195 }
196
197 /* Do not try to allocate the TSB hash table if we
198 * don't have one already. We have various locks held
199 * and thus we'll end up doing a GFP_KERNEL allocation
200 * in an atomic context.
201 *
202 * Instead, we let the first TLB miss on a hugepage
203 * take care of this.
204 */
205 }
206
207 if (!pmd_none(orig)) {
208 addr &= HPAGE_MASK;
209 if (pmd_trans_huge(orig)) {
210 pte_t orig_pte = __pte(pmd_val(orig));
211 bool exec = pte_exec(orig_pte);
212
213 tlb_batch_add_one(mm, addr, exec, true);
214 tlb_batch_add_one(mm, addr + REAL_HPAGE_SIZE, exec,
215 true);
216 } else {
217 tlb_batch_pmd_scan(mm, addr, orig);
218 }
219 }
220}
221
222/*
223 * This routine is only called when splitting a THP
224 */
225void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
226 pmd_t *pmdp)
227{
228 pmd_t entry = *pmdp;
229
230 pmd_val(entry) &= ~_PAGE_VALID;
231
232 set_pmd_at(vma->vm_mm, address, pmdp, entry);
233 flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
234
235 /*
236 * set_pmd_at() will not be called in a way to decrement
237 * thp_pte_count when splitting a THP, so do it now.
238 * Sanity check pmd before doing the actual decrement.
239 */
240 if ((pmd_val(entry) & _PAGE_PMD_HUGE) &&
241 !is_huge_zero_page(pmd_page(entry)))
242 (vma->vm_mm)->context.thp_pte_count--;
243}
244
245void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
246 pgtable_t pgtable)
247{
248 struct list_head *lh = (struct list_head *) pgtable;
249
250 assert_spin_locked(&mm->page_table_lock);
251
252 /* FIFO */
253 if (!pmd_huge_pte(mm, pmdp))
254 INIT_LIST_HEAD(lh);
255 else
256 list_add(lh, (struct list_head *) pmd_huge_pte(mm, pmdp));
257 pmd_huge_pte(mm, pmdp) = pgtable;
258}
259
260pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
261{
262 struct list_head *lh;
263 pgtable_t pgtable;
264
265 assert_spin_locked(&mm->page_table_lock);
266
267 /* FIFO */
268 pgtable = pmd_huge_pte(mm, pmdp);
269 lh = (struct list_head *) pgtable;
270 if (list_empty(lh))
271 pmd_huge_pte(mm, pmdp) = NULL;
272 else {
273 pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next;
274 list_del(lh);
275 }
276 pte_val(pgtable[0]) = 0;
277 pte_val(pgtable[1]) = 0;
278
279 return pgtable;
280}
281#endif /* CONFIG_TRANSPARENT_HUGEPAGE */