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1/*
2 * SPARC64 Huge TLB page support.
3 *
4 * Copyright (C) 2002, 2003, 2006 David S. Miller (davem@davemloft.net)
5 */
6
7#include <linux/init.h>
8#include <linux/module.h>
9#include <linux/fs.h>
10#include <linux/mm.h>
11#include <linux/hugetlb.h>
12#include <linux/pagemap.h>
13#include <linux/sysctl.h>
14
15#include <asm/mman.h>
16#include <asm/pgalloc.h>
17#include <asm/tlb.h>
18#include <asm/tlbflush.h>
19#include <asm/cacheflush.h>
20#include <asm/mmu_context.h>
21
22/* Slightly simplified from the non-hugepage variant because by
23 * definition we don't have to worry about any page coloring stuff
24 */
25#define VA_EXCLUDE_START (0x0000080000000000UL - (1UL << 32UL))
26#define VA_EXCLUDE_END (0xfffff80000000000UL + (1UL << 32UL))
27
28static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *filp,
29 unsigned long addr,
30 unsigned long len,
31 unsigned long pgoff,
32 unsigned long flags)
33{
34 struct mm_struct *mm = current->mm;
35 struct vm_area_struct * vma;
36 unsigned long task_size = TASK_SIZE;
37 unsigned long start_addr;
38
39 if (test_thread_flag(TIF_32BIT))
40 task_size = STACK_TOP32;
41 if (unlikely(len >= VA_EXCLUDE_START))
42 return -ENOMEM;
43
44 if (len > mm->cached_hole_size) {
45 start_addr = addr = mm->free_area_cache;
46 } else {
47 start_addr = addr = TASK_UNMAPPED_BASE;
48 mm->cached_hole_size = 0;
49 }
50
51 task_size -= len;
52
53full_search:
54 addr = ALIGN(addr, HPAGE_SIZE);
55
56 for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
57 /* At this point: (!vma || addr < vma->vm_end). */
58 if (addr < VA_EXCLUDE_START &&
59 (addr + len) >= VA_EXCLUDE_START) {
60 addr = VA_EXCLUDE_END;
61 vma = find_vma(mm, VA_EXCLUDE_END);
62 }
63 if (unlikely(task_size < addr)) {
64 if (start_addr != TASK_UNMAPPED_BASE) {
65 start_addr = addr = TASK_UNMAPPED_BASE;
66 mm->cached_hole_size = 0;
67 goto full_search;
68 }
69 return -ENOMEM;
70 }
71 if (likely(!vma || addr + len <= vma->vm_start)) {
72 /*
73 * Remember the place where we stopped the search:
74 */
75 mm->free_area_cache = addr + len;
76 return addr;
77 }
78 if (addr + mm->cached_hole_size < vma->vm_start)
79 mm->cached_hole_size = vma->vm_start - addr;
80
81 addr = ALIGN(vma->vm_end, HPAGE_SIZE);
82 }
83}
84
85static unsigned long
86hugetlb_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
87 const unsigned long len,
88 const unsigned long pgoff,
89 const unsigned long flags)
90{
91 struct vm_area_struct *vma;
92 struct mm_struct *mm = current->mm;
93 unsigned long addr = addr0;
94
95 /* This should only ever run for 32-bit processes. */
96 BUG_ON(!test_thread_flag(TIF_32BIT));
97
98 /* check if free_area_cache is useful for us */
99 if (len <= mm->cached_hole_size) {
100 mm->cached_hole_size = 0;
101 mm->free_area_cache = mm->mmap_base;
102 }
103
104 /* either no address requested or can't fit in requested address hole */
105 addr = mm->free_area_cache & HPAGE_MASK;
106
107 /* make sure it can fit in the remaining address space */
108 if (likely(addr > len)) {
109 vma = find_vma(mm, addr-len);
110 if (!vma || addr <= vma->vm_start) {
111 /* remember the address as a hint for next time */
112 return (mm->free_area_cache = addr-len);
113 }
114 }
115
116 if (unlikely(mm->mmap_base < len))
117 goto bottomup;
118
119 addr = (mm->mmap_base-len) & HPAGE_MASK;
120
121 do {
122 /*
123 * Lookup failure means no vma is above this address,
124 * else if new region fits below vma->vm_start,
125 * return with success:
126 */
127 vma = find_vma(mm, addr);
128 if (likely(!vma || addr+len <= vma->vm_start)) {
129 /* remember the address as a hint for next time */
130 return (mm->free_area_cache = addr);
131 }
132
133 /* remember the largest hole we saw so far */
134 if (addr + mm->cached_hole_size < vma->vm_start)
135 mm->cached_hole_size = vma->vm_start - addr;
136
137 /* try just below the current vma->vm_start */
138 addr = (vma->vm_start-len) & HPAGE_MASK;
139 } while (likely(len < vma->vm_start));
140
141bottomup:
142 /*
143 * A failed mmap() very likely causes application failure,
144 * so fall back to the bottom-up function here. This scenario
145 * can happen with large stack limits and large mmap()
146 * allocations.
147 */
148 mm->cached_hole_size = ~0UL;
149 mm->free_area_cache = TASK_UNMAPPED_BASE;
150 addr = arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
151 /*
152 * Restore the topdown base:
153 */
154 mm->free_area_cache = mm->mmap_base;
155 mm->cached_hole_size = ~0UL;
156
157 return addr;
158}
159
160unsigned long
161hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
162 unsigned long len, unsigned long pgoff, unsigned long flags)
163{
164 struct mm_struct *mm = current->mm;
165 struct vm_area_struct *vma;
166 unsigned long task_size = TASK_SIZE;
167
168 if (test_thread_flag(TIF_32BIT))
169 task_size = STACK_TOP32;
170
171 if (len & ~HPAGE_MASK)
172 return -EINVAL;
173 if (len > task_size)
174 return -ENOMEM;
175
176 if (flags & MAP_FIXED) {
177 if (prepare_hugepage_range(file, addr, len))
178 return -EINVAL;
179 return addr;
180 }
181
182 if (addr) {
183 addr = ALIGN(addr, HPAGE_SIZE);
184 vma = find_vma(mm, addr);
185 if (task_size - len >= addr &&
186 (!vma || addr + len <= vma->vm_start))
187 return addr;
188 }
189 if (mm->get_unmapped_area == arch_get_unmapped_area)
190 return hugetlb_get_unmapped_area_bottomup(file, addr, len,
191 pgoff, flags);
192 else
193 return hugetlb_get_unmapped_area_topdown(file, addr, len,
194 pgoff, flags);
195}
196
197pte_t *huge_pte_alloc(struct mm_struct *mm,
198 unsigned long addr, unsigned long sz)
199{
200 pgd_t *pgd;
201 pud_t *pud;
202 pmd_t *pmd;
203 pte_t *pte = NULL;
204
205 /* We must align the address, because our caller will run
206 * set_huge_pte_at() on whatever we return, which writes out
207 * all of the sub-ptes for the hugepage range. So we have
208 * to give it the first such sub-pte.
209 */
210 addr &= HPAGE_MASK;
211
212 pgd = pgd_offset(mm, addr);
213 pud = pud_alloc(mm, pgd, addr);
214 if (pud) {
215 pmd = pmd_alloc(mm, pud, addr);
216 if (pmd)
217 pte = pte_alloc_map(mm, NULL, pmd, addr);
218 }
219 return pte;
220}
221
222pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
223{
224 pgd_t *pgd;
225 pud_t *pud;
226 pmd_t *pmd;
227 pte_t *pte = NULL;
228
229 addr &= HPAGE_MASK;
230
231 pgd = pgd_offset(mm, addr);
232 if (!pgd_none(*pgd)) {
233 pud = pud_offset(pgd, addr);
234 if (!pud_none(*pud)) {
235 pmd = pmd_offset(pud, addr);
236 if (!pmd_none(*pmd))
237 pte = pte_offset_map(pmd, addr);
238 }
239 }
240 return pte;
241}
242
243int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
244{
245 return 0;
246}
247
248void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
249 pte_t *ptep, pte_t entry)
250{
251 int i;
252
253 if (!pte_present(*ptep) && pte_present(entry))
254 mm->context.huge_pte_count++;
255
256 addr &= HPAGE_MASK;
257 for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
258 set_pte_at(mm, addr, ptep, entry);
259 ptep++;
260 addr += PAGE_SIZE;
261 pte_val(entry) += PAGE_SIZE;
262 }
263}
264
265pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
266 pte_t *ptep)
267{
268 pte_t entry;
269 int i;
270
271 entry = *ptep;
272 if (pte_present(entry))
273 mm->context.huge_pte_count--;
274
275 addr &= HPAGE_MASK;
276
277 for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
278 pte_clear(mm, addr, ptep);
279 addr += PAGE_SIZE;
280 ptep++;
281 }
282
283 return entry;
284}
285
286struct page *follow_huge_addr(struct mm_struct *mm,
287 unsigned long address, int write)
288{
289 return ERR_PTR(-EINVAL);
290}
291
292int pmd_huge(pmd_t pmd)
293{
294 return 0;
295}
296
297int pud_huge(pud_t pud)
298{
299 return 0;
300}
301
302struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
303 pmd_t *pmd, int write)
304{
305 return NULL;
306}
307
308static void context_reload(void *__data)
309{
310 struct mm_struct *mm = __data;
311
312 if (mm == current->mm)
313 load_secondary_context(mm);
314}
315
316void hugetlb_prefault_arch_hook(struct mm_struct *mm)
317{
318 struct tsb_config *tp = &mm->context.tsb_block[MM_TSB_HUGE];
319
320 if (likely(tp->tsb != NULL))
321 return;
322
323 tsb_grow(mm, MM_TSB_HUGE, 0);
324 tsb_context_switch(mm);
325 smp_tsb_sync(mm);
326
327 /* On UltraSPARC-III+ and later, configure the second half of
328 * the Data-TLB for huge pages.
329 */
330 if (tlb_type == cheetah_plus) {
331 unsigned long ctx;
332
333 spin_lock(&ctx_alloc_lock);
334 ctx = mm->context.sparc64_ctx_val;
335 ctx &= ~CTX_PGSZ_MASK;
336 ctx |= CTX_PGSZ_BASE << CTX_PGSZ0_SHIFT;
337 ctx |= CTX_PGSZ_HUGE << CTX_PGSZ1_SHIFT;
338
339 if (ctx != mm->context.sparc64_ctx_val) {
340 /* When changing the page size fields, we
341 * must perform a context flush so that no
342 * stale entries match. This flush must
343 * occur with the original context register
344 * settings.
345 */
346 do_flush_tlb_mm(mm);
347
348 /* Reload the context register of all processors
349 * also executing in this address space.
350 */
351 mm->context.sparc64_ctx_val = ctx;
352 on_each_cpu(context_reload, mm, 0);
353 }
354 spin_unlock(&ctx_alloc_lock);
355 }
356}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * SPARC64 Huge TLB page support.
4 *
5 * Copyright (C) 2002, 2003, 2006 David S. Miller (davem@davemloft.net)
6 */
7
8#include <linux/fs.h>
9#include <linux/mm.h>
10#include <linux/sched/mm.h>
11#include <linux/hugetlb.h>
12#include <linux/pagemap.h>
13#include <linux/sysctl.h>
14
15#include <asm/mman.h>
16#include <asm/pgalloc.h>
17#include <asm/tlb.h>
18#include <asm/tlbflush.h>
19#include <asm/cacheflush.h>
20#include <asm/mmu_context.h>
21
22/* Slightly simplified from the non-hugepage variant because by
23 * definition we don't have to worry about any page coloring stuff
24 */
25
26static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *filp,
27 unsigned long addr,
28 unsigned long len,
29 unsigned long pgoff,
30 unsigned long flags)
31{
32 struct hstate *h = hstate_file(filp);
33 unsigned long task_size = TASK_SIZE;
34 struct vm_unmapped_area_info info;
35
36 if (test_thread_flag(TIF_32BIT))
37 task_size = STACK_TOP32;
38
39 info.flags = 0;
40 info.length = len;
41 info.low_limit = TASK_UNMAPPED_BASE;
42 info.high_limit = min(task_size, VA_EXCLUDE_START);
43 info.align_mask = PAGE_MASK & ~huge_page_mask(h);
44 info.align_offset = 0;
45 addr = vm_unmapped_area(&info);
46
47 if ((addr & ~PAGE_MASK) && task_size > VA_EXCLUDE_END) {
48 VM_BUG_ON(addr != -ENOMEM);
49 info.low_limit = VA_EXCLUDE_END;
50 info.high_limit = task_size;
51 addr = vm_unmapped_area(&info);
52 }
53
54 return addr;
55}
56
57static unsigned long
58hugetlb_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
59 const unsigned long len,
60 const unsigned long pgoff,
61 const unsigned long flags)
62{
63 struct hstate *h = hstate_file(filp);
64 struct mm_struct *mm = current->mm;
65 unsigned long addr = addr0;
66 struct vm_unmapped_area_info info;
67
68 /* This should only ever run for 32-bit processes. */
69 BUG_ON(!test_thread_flag(TIF_32BIT));
70
71 info.flags = VM_UNMAPPED_AREA_TOPDOWN;
72 info.length = len;
73 info.low_limit = PAGE_SIZE;
74 info.high_limit = mm->mmap_base;
75 info.align_mask = PAGE_MASK & ~huge_page_mask(h);
76 info.align_offset = 0;
77 addr = vm_unmapped_area(&info);
78
79 /*
80 * A failed mmap() very likely causes application failure,
81 * so fall back to the bottom-up function here. This scenario
82 * can happen with large stack limits and large mmap()
83 * allocations.
84 */
85 if (addr & ~PAGE_MASK) {
86 VM_BUG_ON(addr != -ENOMEM);
87 info.flags = 0;
88 info.low_limit = TASK_UNMAPPED_BASE;
89 info.high_limit = STACK_TOP32;
90 addr = vm_unmapped_area(&info);
91 }
92
93 return addr;
94}
95
96unsigned long
97hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
98 unsigned long len, unsigned long pgoff, unsigned long flags)
99{
100 struct hstate *h = hstate_file(file);
101 struct mm_struct *mm = current->mm;
102 struct vm_area_struct *vma;
103 unsigned long task_size = TASK_SIZE;
104
105 if (test_thread_flag(TIF_32BIT))
106 task_size = STACK_TOP32;
107
108 if (len & ~huge_page_mask(h))
109 return -EINVAL;
110 if (len > task_size)
111 return -ENOMEM;
112
113 if (flags & MAP_FIXED) {
114 if (prepare_hugepage_range(file, addr, len))
115 return -EINVAL;
116 return addr;
117 }
118
119 if (addr) {
120 addr = ALIGN(addr, huge_page_size(h));
121 vma = find_vma(mm, addr);
122 if (task_size - len >= addr &&
123 (!vma || addr + len <= vm_start_gap(vma)))
124 return addr;
125 }
126 if (mm->get_unmapped_area == arch_get_unmapped_area)
127 return hugetlb_get_unmapped_area_bottomup(file, addr, len,
128 pgoff, flags);
129 else
130 return hugetlb_get_unmapped_area_topdown(file, addr, len,
131 pgoff, flags);
132}
133
134static pte_t sun4u_hugepage_shift_to_tte(pte_t entry, unsigned int shift)
135{
136 return entry;
137}
138
139static pte_t sun4v_hugepage_shift_to_tte(pte_t entry, unsigned int shift)
140{
141 unsigned long hugepage_size = _PAGE_SZ4MB_4V;
142
143 pte_val(entry) = pte_val(entry) & ~_PAGE_SZALL_4V;
144
145 switch (shift) {
146 case HPAGE_16GB_SHIFT:
147 hugepage_size = _PAGE_SZ16GB_4V;
148 pte_val(entry) |= _PAGE_PUD_HUGE;
149 break;
150 case HPAGE_2GB_SHIFT:
151 hugepage_size = _PAGE_SZ2GB_4V;
152 pte_val(entry) |= _PAGE_PMD_HUGE;
153 break;
154 case HPAGE_256MB_SHIFT:
155 hugepage_size = _PAGE_SZ256MB_4V;
156 pte_val(entry) |= _PAGE_PMD_HUGE;
157 break;
158 case HPAGE_SHIFT:
159 pte_val(entry) |= _PAGE_PMD_HUGE;
160 break;
161 case HPAGE_64K_SHIFT:
162 hugepage_size = _PAGE_SZ64K_4V;
163 break;
164 default:
165 WARN_ONCE(1, "unsupported hugepage shift=%u\n", shift);
166 }
167
168 pte_val(entry) = pte_val(entry) | hugepage_size;
169 return entry;
170}
171
172static pte_t hugepage_shift_to_tte(pte_t entry, unsigned int shift)
173{
174 if (tlb_type == hypervisor)
175 return sun4v_hugepage_shift_to_tte(entry, shift);
176 else
177 return sun4u_hugepage_shift_to_tte(entry, shift);
178}
179
180pte_t arch_make_huge_pte(pte_t entry, unsigned int shift, vm_flags_t flags)
181{
182 pte_t pte;
183
184 entry = pte_mkhuge(entry);
185 pte = hugepage_shift_to_tte(entry, shift);
186
187#ifdef CONFIG_SPARC64
188 /* If this vma has ADI enabled on it, turn on TTE.mcd
189 */
190 if (flags & VM_SPARC_ADI)
191 return pte_mkmcd(pte);
192 else
193 return pte_mknotmcd(pte);
194#else
195 return pte;
196#endif
197}
198
199static unsigned int sun4v_huge_tte_to_shift(pte_t entry)
200{
201 unsigned long tte_szbits = pte_val(entry) & _PAGE_SZALL_4V;
202 unsigned int shift;
203
204 switch (tte_szbits) {
205 case _PAGE_SZ16GB_4V:
206 shift = HPAGE_16GB_SHIFT;
207 break;
208 case _PAGE_SZ2GB_4V:
209 shift = HPAGE_2GB_SHIFT;
210 break;
211 case _PAGE_SZ256MB_4V:
212 shift = HPAGE_256MB_SHIFT;
213 break;
214 case _PAGE_SZ4MB_4V:
215 shift = REAL_HPAGE_SHIFT;
216 break;
217 case _PAGE_SZ64K_4V:
218 shift = HPAGE_64K_SHIFT;
219 break;
220 default:
221 shift = PAGE_SHIFT;
222 break;
223 }
224 return shift;
225}
226
227static unsigned int sun4u_huge_tte_to_shift(pte_t entry)
228{
229 unsigned long tte_szbits = pte_val(entry) & _PAGE_SZALL_4U;
230 unsigned int shift;
231
232 switch (tte_szbits) {
233 case _PAGE_SZ256MB_4U:
234 shift = HPAGE_256MB_SHIFT;
235 break;
236 case _PAGE_SZ4MB_4U:
237 shift = REAL_HPAGE_SHIFT;
238 break;
239 case _PAGE_SZ64K_4U:
240 shift = HPAGE_64K_SHIFT;
241 break;
242 default:
243 shift = PAGE_SHIFT;
244 break;
245 }
246 return shift;
247}
248
249static unsigned long tte_to_shift(pte_t entry)
250{
251 if (tlb_type == hypervisor)
252 return sun4v_huge_tte_to_shift(entry);
253
254 return sun4u_huge_tte_to_shift(entry);
255}
256
257static unsigned int huge_tte_to_shift(pte_t entry)
258{
259 unsigned long shift = tte_to_shift(entry);
260
261 if (shift == PAGE_SHIFT)
262 WARN_ONCE(1, "tto_to_shift: invalid hugepage tte=0x%lx\n",
263 pte_val(entry));
264
265 return shift;
266}
267
268static unsigned long huge_tte_to_size(pte_t pte)
269{
270 unsigned long size = 1UL << huge_tte_to_shift(pte);
271
272 if (size == REAL_HPAGE_SIZE)
273 size = HPAGE_SIZE;
274 return size;
275}
276
277unsigned long pud_leaf_size(pud_t pud) { return 1UL << tte_to_shift(*(pte_t *)&pud); }
278unsigned long pmd_leaf_size(pmd_t pmd) { return 1UL << tte_to_shift(*(pte_t *)&pmd); }
279unsigned long pte_leaf_size(pte_t pte) { return 1UL << tte_to_shift(pte); }
280
281pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
282 unsigned long addr, unsigned long sz)
283{
284 pgd_t *pgd;
285 p4d_t *p4d;
286 pud_t *pud;
287 pmd_t *pmd;
288
289 pgd = pgd_offset(mm, addr);
290 p4d = p4d_offset(pgd, addr);
291 pud = pud_alloc(mm, p4d, addr);
292 if (!pud)
293 return NULL;
294 if (sz >= PUD_SIZE)
295 return (pte_t *)pud;
296 pmd = pmd_alloc(mm, pud, addr);
297 if (!pmd)
298 return NULL;
299 if (sz >= PMD_SIZE)
300 return (pte_t *)pmd;
301 return pte_alloc_huge(mm, pmd, addr);
302}
303
304pte_t *huge_pte_offset(struct mm_struct *mm,
305 unsigned long addr, unsigned long sz)
306{
307 pgd_t *pgd;
308 p4d_t *p4d;
309 pud_t *pud;
310 pmd_t *pmd;
311
312 pgd = pgd_offset(mm, addr);
313 if (pgd_none(*pgd))
314 return NULL;
315 p4d = p4d_offset(pgd, addr);
316 if (p4d_none(*p4d))
317 return NULL;
318 pud = pud_offset(p4d, addr);
319 if (pud_none(*pud))
320 return NULL;
321 if (is_hugetlb_pud(*pud))
322 return (pte_t *)pud;
323 pmd = pmd_offset(pud, addr);
324 if (pmd_none(*pmd))
325 return NULL;
326 if (is_hugetlb_pmd(*pmd))
327 return (pte_t *)pmd;
328 return pte_offset_huge(pmd, addr);
329}
330
331void __set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
332 pte_t *ptep, pte_t entry)
333{
334 unsigned int nptes, orig_shift, shift;
335 unsigned long i, size;
336 pte_t orig;
337
338 size = huge_tte_to_size(entry);
339
340 shift = PAGE_SHIFT;
341 if (size >= PUD_SIZE)
342 shift = PUD_SHIFT;
343 else if (size >= PMD_SIZE)
344 shift = PMD_SHIFT;
345 else
346 shift = PAGE_SHIFT;
347
348 nptes = size >> shift;
349
350 if (!pte_present(*ptep) && pte_present(entry))
351 mm->context.hugetlb_pte_count += nptes;
352
353 addr &= ~(size - 1);
354 orig = *ptep;
355 orig_shift = pte_none(orig) ? PAGE_SHIFT : huge_tte_to_shift(orig);
356
357 for (i = 0; i < nptes; i++)
358 ptep[i] = __pte(pte_val(entry) + (i << shift));
359
360 maybe_tlb_batch_add(mm, addr, ptep, orig, 0, orig_shift);
361 /* An HPAGE_SIZE'ed page is composed of two REAL_HPAGE_SIZE'ed pages */
362 if (size == HPAGE_SIZE)
363 maybe_tlb_batch_add(mm, addr + REAL_HPAGE_SIZE, ptep, orig, 0,
364 orig_shift);
365}
366
367void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
368 pte_t *ptep, pte_t entry, unsigned long sz)
369{
370 __set_huge_pte_at(mm, addr, ptep, entry);
371}
372
373pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
374 pte_t *ptep)
375{
376 unsigned int i, nptes, orig_shift, shift;
377 unsigned long size;
378 pte_t entry;
379
380 entry = *ptep;
381 size = huge_tte_to_size(entry);
382
383 shift = PAGE_SHIFT;
384 if (size >= PUD_SIZE)
385 shift = PUD_SHIFT;
386 else if (size >= PMD_SIZE)
387 shift = PMD_SHIFT;
388 else
389 shift = PAGE_SHIFT;
390
391 nptes = size >> shift;
392 orig_shift = pte_none(entry) ? PAGE_SHIFT : huge_tte_to_shift(entry);
393
394 if (pte_present(entry))
395 mm->context.hugetlb_pte_count -= nptes;
396
397 addr &= ~(size - 1);
398 for (i = 0; i < nptes; i++)
399 ptep[i] = __pte(0UL);
400
401 maybe_tlb_batch_add(mm, addr, ptep, entry, 0, orig_shift);
402 /* An HPAGE_SIZE'ed page is composed of two REAL_HPAGE_SIZE'ed pages */
403 if (size == HPAGE_SIZE)
404 maybe_tlb_batch_add(mm, addr + REAL_HPAGE_SIZE, ptep, entry, 0,
405 orig_shift);
406
407 return entry;
408}
409
410int pmd_huge(pmd_t pmd)
411{
412 return !pmd_none(pmd) &&
413 (pmd_val(pmd) & (_PAGE_VALID|_PAGE_PMD_HUGE)) != _PAGE_VALID;
414}
415
416int pud_huge(pud_t pud)
417{
418 return !pud_none(pud) &&
419 (pud_val(pud) & (_PAGE_VALID|_PAGE_PUD_HUGE)) != _PAGE_VALID;
420}
421
422static void hugetlb_free_pte_range(struct mmu_gather *tlb, pmd_t *pmd,
423 unsigned long addr)
424{
425 pgtable_t token = pmd_pgtable(*pmd);
426
427 pmd_clear(pmd);
428 pte_free_tlb(tlb, token, addr);
429 mm_dec_nr_ptes(tlb->mm);
430}
431
432static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
433 unsigned long addr, unsigned long end,
434 unsigned long floor, unsigned long ceiling)
435{
436 pmd_t *pmd;
437 unsigned long next;
438 unsigned long start;
439
440 start = addr;
441 pmd = pmd_offset(pud, addr);
442 do {
443 next = pmd_addr_end(addr, end);
444 if (pmd_none(*pmd))
445 continue;
446 if (is_hugetlb_pmd(*pmd))
447 pmd_clear(pmd);
448 else
449 hugetlb_free_pte_range(tlb, pmd, addr);
450 } while (pmd++, addr = next, addr != end);
451
452 start &= PUD_MASK;
453 if (start < floor)
454 return;
455 if (ceiling) {
456 ceiling &= PUD_MASK;
457 if (!ceiling)
458 return;
459 }
460 if (end - 1 > ceiling - 1)
461 return;
462
463 pmd = pmd_offset(pud, start);
464 pud_clear(pud);
465 pmd_free_tlb(tlb, pmd, start);
466 mm_dec_nr_pmds(tlb->mm);
467}
468
469static void hugetlb_free_pud_range(struct mmu_gather *tlb, p4d_t *p4d,
470 unsigned long addr, unsigned long end,
471 unsigned long floor, unsigned long ceiling)
472{
473 pud_t *pud;
474 unsigned long next;
475 unsigned long start;
476
477 start = addr;
478 pud = pud_offset(p4d, addr);
479 do {
480 next = pud_addr_end(addr, end);
481 if (pud_none_or_clear_bad(pud))
482 continue;
483 if (is_hugetlb_pud(*pud))
484 pud_clear(pud);
485 else
486 hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
487 ceiling);
488 } while (pud++, addr = next, addr != end);
489
490 start &= PGDIR_MASK;
491 if (start < floor)
492 return;
493 if (ceiling) {
494 ceiling &= PGDIR_MASK;
495 if (!ceiling)
496 return;
497 }
498 if (end - 1 > ceiling - 1)
499 return;
500
501 pud = pud_offset(p4d, start);
502 p4d_clear(p4d);
503 pud_free_tlb(tlb, pud, start);
504 mm_dec_nr_puds(tlb->mm);
505}
506
507void hugetlb_free_pgd_range(struct mmu_gather *tlb,
508 unsigned long addr, unsigned long end,
509 unsigned long floor, unsigned long ceiling)
510{
511 pgd_t *pgd;
512 p4d_t *p4d;
513 unsigned long next;
514
515 addr &= PMD_MASK;
516 if (addr < floor) {
517 addr += PMD_SIZE;
518 if (!addr)
519 return;
520 }
521 if (ceiling) {
522 ceiling &= PMD_MASK;
523 if (!ceiling)
524 return;
525 }
526 if (end - 1 > ceiling - 1)
527 end -= PMD_SIZE;
528 if (addr > end - 1)
529 return;
530
531 pgd = pgd_offset(tlb->mm, addr);
532 p4d = p4d_offset(pgd, addr);
533 do {
534 next = p4d_addr_end(addr, end);
535 if (p4d_none_or_clear_bad(p4d))
536 continue;
537 hugetlb_free_pud_range(tlb, p4d, addr, next, floor, ceiling);
538 } while (p4d++, addr = next, addr != end);
539}