Commit | Line | Data |
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3610cce8 | 1 | /* |
a53c8fab | 2 | * Copyright IBM Corp. 2007, 2011 |
3610cce8 MS |
3 | * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> |
4 | */ | |
5 | ||
6 | #include <linux/sched.h> | |
7 | #include <linux/kernel.h> | |
8 | #include <linux/errno.h> | |
5a0e3ad6 | 9 | #include <linux/gfp.h> |
3610cce8 MS |
10 | #include <linux/mm.h> |
11 | #include <linux/swap.h> | |
12 | #include <linux/smp.h> | |
13 | #include <linux/highmem.h> | |
3610cce8 MS |
14 | #include <linux/pagemap.h> |
15 | #include <linux/spinlock.h> | |
16 | #include <linux/module.h> | |
17 | #include <linux/quicklist.h> | |
80217147 | 18 | #include <linux/rcupdate.h> |
e5992f2e | 19 | #include <linux/slab.h> |
3610cce8 | 20 | |
3610cce8 MS |
21 | #include <asm/pgtable.h> |
22 | #include <asm/pgalloc.h> | |
23 | #include <asm/tlb.h> | |
24 | #include <asm/tlbflush.h> | |
6252d702 | 25 | #include <asm/mmu_context.h> |
3610cce8 MS |
26 | |
27 | #ifndef CONFIG_64BIT | |
28 | #define ALLOC_ORDER 1 | |
36409f63 | 29 | #define FRAG_MASK 0x0f |
3610cce8 MS |
30 | #else |
31 | #define ALLOC_ORDER 2 | |
36409f63 | 32 | #define FRAG_MASK 0x03 |
3610cce8 MS |
33 | #endif |
34 | ||
239a6425 | 35 | |
043d0708 | 36 | unsigned long *crst_table_alloc(struct mm_struct *mm) |
3610cce8 MS |
37 | { |
38 | struct page *page = alloc_pages(GFP_KERNEL, ALLOC_ORDER); | |
39 | ||
40 | if (!page) | |
41 | return NULL; | |
3610cce8 MS |
42 | return (unsigned long *) page_to_phys(page); |
43 | } | |
44 | ||
80217147 MS |
45 | void crst_table_free(struct mm_struct *mm, unsigned long *table) |
46 | { | |
043d0708 | 47 | free_pages((unsigned long) table, ALLOC_ORDER); |
80217147 MS |
48 | } |
49 | ||
6252d702 MS |
50 | #ifdef CONFIG_64BIT |
51 | int crst_table_upgrade(struct mm_struct *mm, unsigned long limit) | |
52 | { | |
53 | unsigned long *table, *pgd; | |
54 | unsigned long entry; | |
55 | ||
56 | BUG_ON(limit > (1UL << 53)); | |
57 | repeat: | |
043d0708 | 58 | table = crst_table_alloc(mm); |
6252d702 MS |
59 | if (!table) |
60 | return -ENOMEM; | |
80217147 | 61 | spin_lock_bh(&mm->page_table_lock); |
6252d702 MS |
62 | if (mm->context.asce_limit < limit) { |
63 | pgd = (unsigned long *) mm->pgd; | |
64 | if (mm->context.asce_limit <= (1UL << 31)) { | |
65 | entry = _REGION3_ENTRY_EMPTY; | |
66 | mm->context.asce_limit = 1UL << 42; | |
67 | mm->context.asce_bits = _ASCE_TABLE_LENGTH | | |
68 | _ASCE_USER_BITS | | |
69 | _ASCE_TYPE_REGION3; | |
70 | } else { | |
71 | entry = _REGION2_ENTRY_EMPTY; | |
72 | mm->context.asce_limit = 1UL << 53; | |
73 | mm->context.asce_bits = _ASCE_TABLE_LENGTH | | |
74 | _ASCE_USER_BITS | | |
75 | _ASCE_TYPE_REGION2; | |
76 | } | |
77 | crst_table_init(table, entry); | |
78 | pgd_populate(mm, (pgd_t *) table, (pud_t *) pgd); | |
79 | mm->pgd = (pgd_t *) table; | |
f481bfaf | 80 | mm->task_size = mm->context.asce_limit; |
6252d702 MS |
81 | table = NULL; |
82 | } | |
80217147 | 83 | spin_unlock_bh(&mm->page_table_lock); |
6252d702 MS |
84 | if (table) |
85 | crst_table_free(mm, table); | |
86 | if (mm->context.asce_limit < limit) | |
87 | goto repeat; | |
6252d702 MS |
88 | return 0; |
89 | } | |
90 | ||
91 | void crst_table_downgrade(struct mm_struct *mm, unsigned long limit) | |
92 | { | |
93 | pgd_t *pgd; | |
94 | ||
6252d702 MS |
95 | while (mm->context.asce_limit > limit) { |
96 | pgd = mm->pgd; | |
97 | switch (pgd_val(*pgd) & _REGION_ENTRY_TYPE_MASK) { | |
98 | case _REGION_ENTRY_TYPE_R2: | |
99 | mm->context.asce_limit = 1UL << 42; | |
100 | mm->context.asce_bits = _ASCE_TABLE_LENGTH | | |
101 | _ASCE_USER_BITS | | |
102 | _ASCE_TYPE_REGION3; | |
103 | break; | |
104 | case _REGION_ENTRY_TYPE_R3: | |
105 | mm->context.asce_limit = 1UL << 31; | |
106 | mm->context.asce_bits = _ASCE_TABLE_LENGTH | | |
107 | _ASCE_USER_BITS | | |
108 | _ASCE_TYPE_SEGMENT; | |
109 | break; | |
110 | default: | |
111 | BUG(); | |
112 | } | |
113 | mm->pgd = (pgd_t *) (pgd_val(*pgd) & _REGION_ENTRY_ORIGIN); | |
f481bfaf | 114 | mm->task_size = mm->context.asce_limit; |
6252d702 MS |
115 | crst_table_free(mm, (unsigned long *) pgd); |
116 | } | |
6252d702 MS |
117 | } |
118 | #endif | |
119 | ||
e5992f2e MS |
120 | #ifdef CONFIG_PGSTE |
121 | ||
122 | /** | |
123 | * gmap_alloc - allocate a guest address space | |
124 | * @mm: pointer to the parent mm_struct | |
125 | * | |
126 | * Returns a guest address space structure. | |
127 | */ | |
128 | struct gmap *gmap_alloc(struct mm_struct *mm) | |
36409f63 | 129 | { |
e5992f2e MS |
130 | struct gmap *gmap; |
131 | struct page *page; | |
132 | unsigned long *table; | |
36409f63 | 133 | |
e5992f2e MS |
134 | gmap = kzalloc(sizeof(struct gmap), GFP_KERNEL); |
135 | if (!gmap) | |
136 | goto out; | |
137 | INIT_LIST_HEAD(&gmap->crst_list); | |
138 | gmap->mm = mm; | |
139 | page = alloc_pages(GFP_KERNEL, ALLOC_ORDER); | |
140 | if (!page) | |
141 | goto out_free; | |
142 | list_add(&page->lru, &gmap->crst_list); | |
143 | table = (unsigned long *) page_to_phys(page); | |
144 | crst_table_init(table, _REGION1_ENTRY_EMPTY); | |
145 | gmap->table = table; | |
480e5926 CB |
146 | gmap->asce = _ASCE_TYPE_REGION1 | _ASCE_TABLE_LENGTH | |
147 | _ASCE_USER_BITS | __pa(table); | |
e5992f2e MS |
148 | list_add(&gmap->list, &mm->context.gmap_list); |
149 | return gmap; | |
150 | ||
151 | out_free: | |
152 | kfree(gmap); | |
153 | out: | |
154 | return NULL; | |
36409f63 | 155 | } |
e5992f2e | 156 | EXPORT_SYMBOL_GPL(gmap_alloc); |
36409f63 | 157 | |
e5992f2e MS |
158 | static int gmap_unlink_segment(struct gmap *gmap, unsigned long *table) |
159 | { | |
160 | struct gmap_pgtable *mp; | |
161 | struct gmap_rmap *rmap; | |
162 | struct page *page; | |
163 | ||
164 | if (*table & _SEGMENT_ENTRY_INV) | |
165 | return 0; | |
166 | page = pfn_to_page(*table >> PAGE_SHIFT); | |
167 | mp = (struct gmap_pgtable *) page->index; | |
168 | list_for_each_entry(rmap, &mp->mapper, list) { | |
169 | if (rmap->entry != table) | |
170 | continue; | |
171 | list_del(&rmap->list); | |
172 | kfree(rmap); | |
173 | break; | |
174 | } | |
175 | *table = _SEGMENT_ENTRY_INV | _SEGMENT_ENTRY_RO | mp->vmaddr; | |
176 | return 1; | |
177 | } | |
178 | ||
179 | static void gmap_flush_tlb(struct gmap *gmap) | |
180 | { | |
181 | if (MACHINE_HAS_IDTE) | |
182 | __tlb_flush_idte((unsigned long) gmap->table | | |
183 | _ASCE_TYPE_REGION1); | |
184 | else | |
185 | __tlb_flush_global(); | |
186 | } | |
187 | ||
188 | /** | |
189 | * gmap_free - free a guest address space | |
190 | * @gmap: pointer to the guest address space structure | |
3610cce8 | 191 | */ |
e5992f2e MS |
192 | void gmap_free(struct gmap *gmap) |
193 | { | |
194 | struct page *page, *next; | |
195 | unsigned long *table; | |
196 | int i; | |
197 | ||
198 | ||
199 | /* Flush tlb. */ | |
200 | if (MACHINE_HAS_IDTE) | |
201 | __tlb_flush_idte((unsigned long) gmap->table | | |
202 | _ASCE_TYPE_REGION1); | |
203 | else | |
204 | __tlb_flush_global(); | |
205 | ||
206 | /* Free all segment & region tables. */ | |
207 | down_read(&gmap->mm->mmap_sem); | |
cc772456 | 208 | spin_lock(&gmap->mm->page_table_lock); |
e5992f2e MS |
209 | list_for_each_entry_safe(page, next, &gmap->crst_list, lru) { |
210 | table = (unsigned long *) page_to_phys(page); | |
211 | if ((*table & _REGION_ENTRY_TYPE_MASK) == 0) | |
212 | /* Remove gmap rmap structures for segment table. */ | |
213 | for (i = 0; i < PTRS_PER_PMD; i++, table++) | |
214 | gmap_unlink_segment(gmap, table); | |
215 | __free_pages(page, ALLOC_ORDER); | |
216 | } | |
cc772456 | 217 | spin_unlock(&gmap->mm->page_table_lock); |
e5992f2e MS |
218 | up_read(&gmap->mm->mmap_sem); |
219 | list_del(&gmap->list); | |
220 | kfree(gmap); | |
221 | } | |
222 | EXPORT_SYMBOL_GPL(gmap_free); | |
223 | ||
224 | /** | |
225 | * gmap_enable - switch primary space to the guest address space | |
226 | * @gmap: pointer to the guest address space structure | |
227 | */ | |
228 | void gmap_enable(struct gmap *gmap) | |
229 | { | |
e5992f2e MS |
230 | S390_lowcore.gmap = (unsigned long) gmap; |
231 | } | |
232 | EXPORT_SYMBOL_GPL(gmap_enable); | |
233 | ||
234 | /** | |
235 | * gmap_disable - switch back to the standard primary address space | |
236 | * @gmap: pointer to the guest address space structure | |
237 | */ | |
238 | void gmap_disable(struct gmap *gmap) | |
239 | { | |
e5992f2e MS |
240 | S390_lowcore.gmap = 0UL; |
241 | } | |
242 | EXPORT_SYMBOL_GPL(gmap_disable); | |
243 | ||
a9162f23 CO |
244 | /* |
245 | * gmap_alloc_table is assumed to be called with mmap_sem held | |
246 | */ | |
e5992f2e MS |
247 | static int gmap_alloc_table(struct gmap *gmap, |
248 | unsigned long *table, unsigned long init) | |
249 | { | |
250 | struct page *page; | |
251 | unsigned long *new; | |
252 | ||
c86cce2a CB |
253 | /* since we dont free the gmap table until gmap_free we can unlock */ |
254 | spin_unlock(&gmap->mm->page_table_lock); | |
e5992f2e | 255 | page = alloc_pages(GFP_KERNEL, ALLOC_ORDER); |
c86cce2a | 256 | spin_lock(&gmap->mm->page_table_lock); |
e5992f2e MS |
257 | if (!page) |
258 | return -ENOMEM; | |
259 | new = (unsigned long *) page_to_phys(page); | |
260 | crst_table_init(new, init); | |
e5992f2e MS |
261 | if (*table & _REGION_ENTRY_INV) { |
262 | list_add(&page->lru, &gmap->crst_list); | |
263 | *table = (unsigned long) new | _REGION_ENTRY_LENGTH | | |
264 | (*table & _REGION_ENTRY_TYPE_MASK); | |
265 | } else | |
266 | __free_pages(page, ALLOC_ORDER); | |
e5992f2e MS |
267 | return 0; |
268 | } | |
269 | ||
270 | /** | |
271 | * gmap_unmap_segment - unmap segment from the guest address space | |
272 | * @gmap: pointer to the guest address space structure | |
273 | * @addr: address in the guest address space | |
274 | * @len: length of the memory area to unmap | |
275 | * | |
276 | * Returns 0 if the unmap succeded, -EINVAL if not. | |
277 | */ | |
278 | int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len) | |
279 | { | |
280 | unsigned long *table; | |
281 | unsigned long off; | |
282 | int flush; | |
283 | ||
284 | if ((to | len) & (PMD_SIZE - 1)) | |
285 | return -EINVAL; | |
286 | if (len == 0 || to + len < to) | |
287 | return -EINVAL; | |
288 | ||
289 | flush = 0; | |
290 | down_read(&gmap->mm->mmap_sem); | |
cc772456 | 291 | spin_lock(&gmap->mm->page_table_lock); |
e5992f2e MS |
292 | for (off = 0; off < len; off += PMD_SIZE) { |
293 | /* Walk the guest addr space page table */ | |
294 | table = gmap->table + (((to + off) >> 53) & 0x7ff); | |
295 | if (*table & _REGION_ENTRY_INV) | |
05873df9 | 296 | goto out; |
e5992f2e MS |
297 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); |
298 | table = table + (((to + off) >> 42) & 0x7ff); | |
299 | if (*table & _REGION_ENTRY_INV) | |
05873df9 | 300 | goto out; |
e5992f2e MS |
301 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); |
302 | table = table + (((to + off) >> 31) & 0x7ff); | |
303 | if (*table & _REGION_ENTRY_INV) | |
05873df9 | 304 | goto out; |
e5992f2e MS |
305 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); |
306 | table = table + (((to + off) >> 20) & 0x7ff); | |
307 | ||
308 | /* Clear segment table entry in guest address space. */ | |
309 | flush |= gmap_unlink_segment(gmap, table); | |
310 | *table = _SEGMENT_ENTRY_INV; | |
311 | } | |
05873df9 | 312 | out: |
cc772456 | 313 | spin_unlock(&gmap->mm->page_table_lock); |
e5992f2e MS |
314 | up_read(&gmap->mm->mmap_sem); |
315 | if (flush) | |
316 | gmap_flush_tlb(gmap); | |
317 | return 0; | |
318 | } | |
319 | EXPORT_SYMBOL_GPL(gmap_unmap_segment); | |
320 | ||
321 | /** | |
322 | * gmap_mmap_segment - map a segment to the guest address space | |
323 | * @gmap: pointer to the guest address space structure | |
324 | * @from: source address in the parent address space | |
325 | * @to: target address in the guest address space | |
326 | * | |
327 | * Returns 0 if the mmap succeded, -EINVAL or -ENOMEM if not. | |
328 | */ | |
329 | int gmap_map_segment(struct gmap *gmap, unsigned long from, | |
330 | unsigned long to, unsigned long len) | |
331 | { | |
332 | unsigned long *table; | |
333 | unsigned long off; | |
334 | int flush; | |
335 | ||
336 | if ((from | to | len) & (PMD_SIZE - 1)) | |
337 | return -EINVAL; | |
338 | if (len == 0 || from + len > PGDIR_SIZE || | |
339 | from + len < from || to + len < to) | |
340 | return -EINVAL; | |
341 | ||
342 | flush = 0; | |
343 | down_read(&gmap->mm->mmap_sem); | |
cc772456 | 344 | spin_lock(&gmap->mm->page_table_lock); |
e5992f2e MS |
345 | for (off = 0; off < len; off += PMD_SIZE) { |
346 | /* Walk the gmap address space page table */ | |
347 | table = gmap->table + (((to + off) >> 53) & 0x7ff); | |
348 | if ((*table & _REGION_ENTRY_INV) && | |
349 | gmap_alloc_table(gmap, table, _REGION2_ENTRY_EMPTY)) | |
350 | goto out_unmap; | |
351 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
352 | table = table + (((to + off) >> 42) & 0x7ff); | |
353 | if ((*table & _REGION_ENTRY_INV) && | |
354 | gmap_alloc_table(gmap, table, _REGION3_ENTRY_EMPTY)) | |
355 | goto out_unmap; | |
356 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
357 | table = table + (((to + off) >> 31) & 0x7ff); | |
358 | if ((*table & _REGION_ENTRY_INV) && | |
359 | gmap_alloc_table(gmap, table, _SEGMENT_ENTRY_EMPTY)) | |
360 | goto out_unmap; | |
361 | table = (unsigned long *) (*table & _REGION_ENTRY_ORIGIN); | |
362 | table = table + (((to + off) >> 20) & 0x7ff); | |
363 | ||
364 | /* Store 'from' address in an invalid segment table entry. */ | |
365 | flush |= gmap_unlink_segment(gmap, table); | |
366 | *table = _SEGMENT_ENTRY_INV | _SEGMENT_ENTRY_RO | (from + off); | |
367 | } | |
cc772456 | 368 | spin_unlock(&gmap->mm->page_table_lock); |
e5992f2e MS |
369 | up_read(&gmap->mm->mmap_sem); |
370 | if (flush) | |
371 | gmap_flush_tlb(gmap); | |
372 | return 0; | |
373 | ||
374 | out_unmap: | |
cc772456 | 375 | spin_unlock(&gmap->mm->page_table_lock); |
e5992f2e MS |
376 | up_read(&gmap->mm->mmap_sem); |
377 | gmap_unmap_segment(gmap, to, len); | |
378 | return -ENOMEM; | |
379 | } | |
380 | EXPORT_SYMBOL_GPL(gmap_map_segment); | |
381 | ||
c5034945 HC |
382 | static unsigned long *gmap_table_walk(unsigned long address, struct gmap *gmap) |
383 | { | |
384 | unsigned long *table; | |
385 | ||
386 | table = gmap->table + ((address >> 53) & 0x7ff); | |
387 | if (unlikely(*table & _REGION_ENTRY_INV)) | |
388 | return ERR_PTR(-EFAULT); | |
389 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
390 | table = table + ((address >> 42) & 0x7ff); | |
391 | if (unlikely(*table & _REGION_ENTRY_INV)) | |
392 | return ERR_PTR(-EFAULT); | |
393 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
394 | table = table + ((address >> 31) & 0x7ff); | |
395 | if (unlikely(*table & _REGION_ENTRY_INV)) | |
396 | return ERR_PTR(-EFAULT); | |
397 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
398 | table = table + ((address >> 20) & 0x7ff); | |
399 | return table; | |
400 | } | |
401 | ||
402 | /** | |
403 | * __gmap_translate - translate a guest address to a user space address | |
404 | * @address: guest address | |
405 | * @gmap: pointer to guest mapping meta data structure | |
406 | * | |
407 | * Returns user space address which corresponds to the guest address or | |
408 | * -EFAULT if no such mapping exists. | |
409 | * This function does not establish potentially missing page table entries. | |
410 | * The mmap_sem of the mm that belongs to the address space must be held | |
411 | * when this function gets called. | |
412 | */ | |
413 | unsigned long __gmap_translate(unsigned long address, struct gmap *gmap) | |
414 | { | |
415 | unsigned long *segment_ptr, vmaddr, segment; | |
416 | struct gmap_pgtable *mp; | |
417 | struct page *page; | |
418 | ||
419 | current->thread.gmap_addr = address; | |
420 | segment_ptr = gmap_table_walk(address, gmap); | |
421 | if (IS_ERR(segment_ptr)) | |
422 | return PTR_ERR(segment_ptr); | |
423 | /* Convert the gmap address to an mm address. */ | |
424 | segment = *segment_ptr; | |
425 | if (!(segment & _SEGMENT_ENTRY_INV)) { | |
426 | page = pfn_to_page(segment >> PAGE_SHIFT); | |
427 | mp = (struct gmap_pgtable *) page->index; | |
428 | return mp->vmaddr | (address & ~PMD_MASK); | |
429 | } else if (segment & _SEGMENT_ENTRY_RO) { | |
430 | vmaddr = segment & _SEGMENT_ENTRY_ORIGIN; | |
431 | return vmaddr | (address & ~PMD_MASK); | |
432 | } | |
433 | return -EFAULT; | |
434 | } | |
435 | EXPORT_SYMBOL_GPL(__gmap_translate); | |
436 | ||
437 | /** | |
438 | * gmap_translate - translate a guest address to a user space address | |
439 | * @address: guest address | |
440 | * @gmap: pointer to guest mapping meta data structure | |
441 | * | |
442 | * Returns user space address which corresponds to the guest address or | |
443 | * -EFAULT if no such mapping exists. | |
444 | * This function does not establish potentially missing page table entries. | |
445 | */ | |
446 | unsigned long gmap_translate(unsigned long address, struct gmap *gmap) | |
447 | { | |
448 | unsigned long rc; | |
449 | ||
450 | down_read(&gmap->mm->mmap_sem); | |
451 | rc = __gmap_translate(address, gmap); | |
452 | up_read(&gmap->mm->mmap_sem); | |
453 | return rc; | |
454 | } | |
455 | EXPORT_SYMBOL_GPL(gmap_translate); | |
456 | ||
ab8e5235 MS |
457 | static int gmap_connect_pgtable(unsigned long segment, |
458 | unsigned long *segment_ptr, | |
459 | struct gmap *gmap) | |
e5992f2e | 460 | { |
ab8e5235 | 461 | unsigned long vmaddr; |
c5034945 | 462 | struct vm_area_struct *vma; |
e5992f2e MS |
463 | struct gmap_pgtable *mp; |
464 | struct gmap_rmap *rmap; | |
c5034945 | 465 | struct mm_struct *mm; |
e5992f2e MS |
466 | struct page *page; |
467 | pgd_t *pgd; | |
468 | pud_t *pud; | |
469 | pmd_t *pmd; | |
470 | ||
ab8e5235 MS |
471 | mm = gmap->mm; |
472 | vmaddr = segment & _SEGMENT_ENTRY_ORIGIN; | |
473 | vma = find_vma(mm, vmaddr); | |
474 | if (!vma || vma->vm_start > vmaddr) | |
475 | return -EFAULT; | |
476 | /* Walk the parent mm page table */ | |
477 | pgd = pgd_offset(mm, vmaddr); | |
478 | pud = pud_alloc(mm, pgd, vmaddr); | |
479 | if (!pud) | |
480 | return -ENOMEM; | |
481 | pmd = pmd_alloc(mm, pud, vmaddr); | |
482 | if (!pmd) | |
483 | return -ENOMEM; | |
484 | if (!pmd_present(*pmd) && | |
485 | __pte_alloc(mm, vma, pmd, vmaddr)) | |
486 | return -ENOMEM; | |
487 | /* pmd now points to a valid segment table entry. */ | |
488 | rmap = kmalloc(sizeof(*rmap), GFP_KERNEL|__GFP_REPEAT); | |
489 | if (!rmap) | |
490 | return -ENOMEM; | |
491 | /* Link gmap segment table entry location to page table. */ | |
492 | page = pmd_page(*pmd); | |
493 | mp = (struct gmap_pgtable *) page->index; | |
494 | rmap->entry = segment_ptr; | |
495 | spin_lock(&mm->page_table_lock); | |
496 | if (*segment_ptr == segment) { | |
497 | list_add(&rmap->list, &mp->mapper); | |
498 | /* Set gmap segment table entry to page table. */ | |
499 | *segment_ptr = pmd_val(*pmd) & PAGE_MASK; | |
500 | rmap = NULL; | |
501 | } | |
502 | spin_unlock(&mm->page_table_lock); | |
503 | kfree(rmap); | |
504 | return 0; | |
505 | } | |
506 | ||
507 | static void gmap_disconnect_pgtable(struct mm_struct *mm, unsigned long *table) | |
508 | { | |
509 | struct gmap_rmap *rmap, *next; | |
510 | struct gmap_pgtable *mp; | |
511 | struct page *page; | |
512 | int flush; | |
513 | ||
514 | flush = 0; | |
515 | spin_lock(&mm->page_table_lock); | |
516 | page = pfn_to_page(__pa(table) >> PAGE_SHIFT); | |
517 | mp = (struct gmap_pgtable *) page->index; | |
518 | list_for_each_entry_safe(rmap, next, &mp->mapper, list) { | |
519 | *rmap->entry = | |
520 | _SEGMENT_ENTRY_INV | _SEGMENT_ENTRY_RO | mp->vmaddr; | |
521 | list_del(&rmap->list); | |
522 | kfree(rmap); | |
523 | flush = 1; | |
524 | } | |
525 | spin_unlock(&mm->page_table_lock); | |
526 | if (flush) | |
527 | __tlb_flush_global(); | |
528 | } | |
529 | ||
530 | /* | |
531 | * this function is assumed to be called with mmap_sem held | |
532 | */ | |
533 | unsigned long __gmap_fault(unsigned long address, struct gmap *gmap) | |
534 | { | |
535 | unsigned long *segment_ptr, segment; | |
536 | struct gmap_pgtable *mp; | |
537 | struct page *page; | |
538 | int rc; | |
539 | ||
e5992f2e | 540 | current->thread.gmap_addr = address; |
c5034945 HC |
541 | segment_ptr = gmap_table_walk(address, gmap); |
542 | if (IS_ERR(segment_ptr)) | |
e5992f2e | 543 | return -EFAULT; |
e5992f2e | 544 | /* Convert the gmap address to an mm address. */ |
ab8e5235 MS |
545 | while (1) { |
546 | segment = *segment_ptr; | |
547 | if (!(segment & _SEGMENT_ENTRY_INV)) { | |
548 | /* Page table is present */ | |
549 | page = pfn_to_page(segment >> PAGE_SHIFT); | |
550 | mp = (struct gmap_pgtable *) page->index; | |
551 | return mp->vmaddr | (address & ~PMD_MASK); | |
552 | } | |
553 | if (!(segment & _SEGMENT_ENTRY_RO)) | |
554 | /* Nothing mapped in the gmap address space. */ | |
555 | break; | |
556 | rc = gmap_connect_pgtable(segment, segment_ptr, gmap); | |
557 | if (rc) | |
558 | return rc; | |
e5992f2e MS |
559 | } |
560 | return -EFAULT; | |
499069e1 CO |
561 | } |
562 | ||
563 | unsigned long gmap_fault(unsigned long address, struct gmap *gmap) | |
564 | { | |
565 | unsigned long rc; | |
566 | ||
567 | down_read(&gmap->mm->mmap_sem); | |
568 | rc = __gmap_fault(address, gmap); | |
569 | up_read(&gmap->mm->mmap_sem); | |
e5992f2e | 570 | |
499069e1 | 571 | return rc; |
e5992f2e MS |
572 | } |
573 | EXPORT_SYMBOL_GPL(gmap_fault); | |
574 | ||
388186bc CB |
575 | void gmap_discard(unsigned long from, unsigned long to, struct gmap *gmap) |
576 | { | |
577 | ||
578 | unsigned long *table, address, size; | |
579 | struct vm_area_struct *vma; | |
580 | struct gmap_pgtable *mp; | |
581 | struct page *page; | |
582 | ||
583 | down_read(&gmap->mm->mmap_sem); | |
584 | address = from; | |
585 | while (address < to) { | |
586 | /* Walk the gmap address space page table */ | |
587 | table = gmap->table + ((address >> 53) & 0x7ff); | |
588 | if (unlikely(*table & _REGION_ENTRY_INV)) { | |
589 | address = (address + PMD_SIZE) & PMD_MASK; | |
590 | continue; | |
591 | } | |
592 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
593 | table = table + ((address >> 42) & 0x7ff); | |
594 | if (unlikely(*table & _REGION_ENTRY_INV)) { | |
595 | address = (address + PMD_SIZE) & PMD_MASK; | |
596 | continue; | |
597 | } | |
598 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
599 | table = table + ((address >> 31) & 0x7ff); | |
600 | if (unlikely(*table & _REGION_ENTRY_INV)) { | |
601 | address = (address + PMD_SIZE) & PMD_MASK; | |
602 | continue; | |
603 | } | |
604 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
605 | table = table + ((address >> 20) & 0x7ff); | |
606 | if (unlikely(*table & _SEGMENT_ENTRY_INV)) { | |
607 | address = (address + PMD_SIZE) & PMD_MASK; | |
608 | continue; | |
609 | } | |
610 | page = pfn_to_page(*table >> PAGE_SHIFT); | |
611 | mp = (struct gmap_pgtable *) page->index; | |
612 | vma = find_vma(gmap->mm, mp->vmaddr); | |
613 | size = min(to - address, PMD_SIZE - (address & ~PMD_MASK)); | |
614 | zap_page_range(vma, mp->vmaddr | (address & ~PMD_MASK), | |
615 | size, NULL); | |
616 | address = (address + PMD_SIZE) & PMD_MASK; | |
617 | } | |
618 | up_read(&gmap->mm->mmap_sem); | |
619 | } | |
620 | EXPORT_SYMBOL_GPL(gmap_discard); | |
621 | ||
e5992f2e MS |
622 | static inline unsigned long *page_table_alloc_pgste(struct mm_struct *mm, |
623 | unsigned long vmaddr) | |
36409f63 MS |
624 | { |
625 | struct page *page; | |
626 | unsigned long *table; | |
e5992f2e | 627 | struct gmap_pgtable *mp; |
36409f63 MS |
628 | |
629 | page = alloc_page(GFP_KERNEL|__GFP_REPEAT); | |
630 | if (!page) | |
631 | return NULL; | |
e5992f2e MS |
632 | mp = kmalloc(sizeof(*mp), GFP_KERNEL|__GFP_REPEAT); |
633 | if (!mp) { | |
634 | __free_page(page); | |
635 | return NULL; | |
636 | } | |
36409f63 | 637 | pgtable_page_ctor(page); |
e5992f2e MS |
638 | mp->vmaddr = vmaddr & PMD_MASK; |
639 | INIT_LIST_HEAD(&mp->mapper); | |
640 | page->index = (unsigned long) mp; | |
36409f63 MS |
641 | atomic_set(&page->_mapcount, 3); |
642 | table = (unsigned long *) page_to_phys(page); | |
643 | clear_table(table, _PAGE_TYPE_EMPTY, PAGE_SIZE/2); | |
644 | clear_table(table + PTRS_PER_PTE, 0, PAGE_SIZE/2); | |
645 | return table; | |
646 | } | |
647 | ||
648 | static inline void page_table_free_pgste(unsigned long *table) | |
649 | { | |
650 | struct page *page; | |
e5992f2e | 651 | struct gmap_pgtable *mp; |
36409f63 MS |
652 | |
653 | page = pfn_to_page(__pa(table) >> PAGE_SHIFT); | |
e5992f2e MS |
654 | mp = (struct gmap_pgtable *) page->index; |
655 | BUG_ON(!list_empty(&mp->mapper)); | |
2320c579 | 656 | pgtable_page_dtor(page); |
36409f63 | 657 | atomic_set(&page->_mapcount, -1); |
e5992f2e | 658 | kfree(mp); |
36409f63 MS |
659 | __free_page(page); |
660 | } | |
36409f63 | 661 | |
e5992f2e MS |
662 | #else /* CONFIG_PGSTE */ |
663 | ||
664 | static inline unsigned long *page_table_alloc_pgste(struct mm_struct *mm, | |
665 | unsigned long vmaddr) | |
666 | { | |
944291de | 667 | return NULL; |
e5992f2e MS |
668 | } |
669 | ||
670 | static inline void page_table_free_pgste(unsigned long *table) | |
671 | { | |
672 | } | |
673 | ||
ab8e5235 MS |
674 | static inline void gmap_disconnect_pgtable(struct mm_struct *mm, |
675 | unsigned long *table) | |
e5992f2e MS |
676 | { |
677 | } | |
678 | ||
679 | #endif /* CONFIG_PGSTE */ | |
680 | ||
681 | static inline unsigned int atomic_xor_bits(atomic_t *v, unsigned int bits) | |
682 | { | |
683 | unsigned int old, new; | |
684 | ||
685 | do { | |
686 | old = atomic_read(v); | |
687 | new = old ^ bits; | |
688 | } while (atomic_cmpxchg(v, old, new) != old); | |
689 | return new; | |
690 | } | |
691 | ||
692 | /* | |
693 | * page table entry allocation/free routines. | |
694 | */ | |
695 | unsigned long *page_table_alloc(struct mm_struct *mm, unsigned long vmaddr) | |
3610cce8 | 696 | { |
41459d36 HC |
697 | unsigned long *uninitialized_var(table); |
698 | struct page *uninitialized_var(page); | |
36409f63 | 699 | unsigned int mask, bit; |
3610cce8 | 700 | |
36409f63 | 701 | if (mm_has_pgste(mm)) |
e5992f2e | 702 | return page_table_alloc_pgste(mm, vmaddr); |
36409f63 | 703 | /* Allocate fragments of a 4K page as 1K/2K page table */ |
80217147 | 704 | spin_lock_bh(&mm->context.list_lock); |
36409f63 | 705 | mask = FRAG_MASK; |
146e4b3c MS |
706 | if (!list_empty(&mm->context.pgtable_list)) { |
707 | page = list_first_entry(&mm->context.pgtable_list, | |
708 | struct page, lru); | |
36409f63 MS |
709 | table = (unsigned long *) page_to_phys(page); |
710 | mask = atomic_read(&page->_mapcount); | |
711 | mask = mask | (mask >> 4); | |
146e4b3c | 712 | } |
36409f63 | 713 | if ((mask & FRAG_MASK) == FRAG_MASK) { |
80217147 | 714 | spin_unlock_bh(&mm->context.list_lock); |
146e4b3c MS |
715 | page = alloc_page(GFP_KERNEL|__GFP_REPEAT); |
716 | if (!page) | |
3610cce8 | 717 | return NULL; |
146e4b3c | 718 | pgtable_page_ctor(page); |
36409f63 | 719 | atomic_set(&page->_mapcount, 1); |
146e4b3c | 720 | table = (unsigned long *) page_to_phys(page); |
36409f63 | 721 | clear_table(table, _PAGE_TYPE_EMPTY, PAGE_SIZE); |
80217147 | 722 | spin_lock_bh(&mm->context.list_lock); |
146e4b3c | 723 | list_add(&page->lru, &mm->context.pgtable_list); |
36409f63 MS |
724 | } else { |
725 | for (bit = 1; mask & bit; bit <<= 1) | |
726 | table += PTRS_PER_PTE; | |
727 | mask = atomic_xor_bits(&page->_mapcount, bit); | |
728 | if ((mask & FRAG_MASK) == FRAG_MASK) | |
729 | list_del(&page->lru); | |
3610cce8 | 730 | } |
80217147 | 731 | spin_unlock_bh(&mm->context.list_lock); |
3610cce8 MS |
732 | return table; |
733 | } | |
734 | ||
36409f63 | 735 | void page_table_free(struct mm_struct *mm, unsigned long *table) |
80217147 MS |
736 | { |
737 | struct page *page; | |
36409f63 | 738 | unsigned int bit, mask; |
80217147 | 739 | |
e5992f2e | 740 | if (mm_has_pgste(mm)) { |
ab8e5235 | 741 | gmap_disconnect_pgtable(mm, table); |
36409f63 | 742 | return page_table_free_pgste(table); |
e5992f2e | 743 | } |
36409f63 | 744 | /* Free 1K/2K page table fragment of a 4K page */ |
80217147 | 745 | page = pfn_to_page(__pa(table) >> PAGE_SHIFT); |
36409f63 MS |
746 | bit = 1 << ((__pa(table) & ~PAGE_MASK)/(PTRS_PER_PTE*sizeof(pte_t))); |
747 | spin_lock_bh(&mm->context.list_lock); | |
748 | if ((atomic_read(&page->_mapcount) & FRAG_MASK) != FRAG_MASK) | |
749 | list_del(&page->lru); | |
750 | mask = atomic_xor_bits(&page->_mapcount, bit); | |
751 | if (mask & FRAG_MASK) | |
752 | list_add(&page->lru, &mm->context.pgtable_list); | |
753 | spin_unlock_bh(&mm->context.list_lock); | |
754 | if (mask == 0) { | |
80217147 | 755 | pgtable_page_dtor(page); |
36409f63 | 756 | atomic_set(&page->_mapcount, -1); |
80217147 MS |
757 | __free_page(page); |
758 | } | |
759 | } | |
760 | ||
36409f63 | 761 | static void __page_table_free_rcu(void *table, unsigned bit) |
3610cce8 | 762 | { |
146e4b3c | 763 | struct page *page; |
3610cce8 | 764 | |
36409f63 MS |
765 | if (bit == FRAG_MASK) |
766 | return page_table_free_pgste(table); | |
36409f63 | 767 | /* Free 1K/2K page table fragment of a 4K page */ |
146e4b3c | 768 | page = pfn_to_page(__pa(table) >> PAGE_SHIFT); |
36409f63 | 769 | if (atomic_xor_bits(&page->_mapcount, bit) == 0) { |
146e4b3c | 770 | pgtable_page_dtor(page); |
36409f63 | 771 | atomic_set(&page->_mapcount, -1); |
146e4b3c MS |
772 | __free_page(page); |
773 | } | |
774 | } | |
3610cce8 | 775 | |
36409f63 | 776 | void page_table_free_rcu(struct mmu_gather *tlb, unsigned long *table) |
80217147 | 777 | { |
36409f63 | 778 | struct mm_struct *mm; |
80217147 | 779 | struct page *page; |
36409f63 | 780 | unsigned int bit, mask; |
80217147 | 781 | |
36409f63 | 782 | mm = tlb->mm; |
36409f63 | 783 | if (mm_has_pgste(mm)) { |
ab8e5235 | 784 | gmap_disconnect_pgtable(mm, table); |
36409f63 MS |
785 | table = (unsigned long *) (__pa(table) | FRAG_MASK); |
786 | tlb_remove_table(tlb, table); | |
787 | return; | |
80217147 | 788 | } |
36409f63 | 789 | bit = 1 << ((__pa(table) & ~PAGE_MASK) / (PTRS_PER_PTE*sizeof(pte_t))); |
80217147 MS |
790 | page = pfn_to_page(__pa(table) >> PAGE_SHIFT); |
791 | spin_lock_bh(&mm->context.list_lock); | |
36409f63 MS |
792 | if ((atomic_read(&page->_mapcount) & FRAG_MASK) != FRAG_MASK) |
793 | list_del(&page->lru); | |
794 | mask = atomic_xor_bits(&page->_mapcount, bit | (bit << 4)); | |
795 | if (mask & FRAG_MASK) | |
796 | list_add_tail(&page->lru, &mm->context.pgtable_list); | |
80217147 | 797 | spin_unlock_bh(&mm->context.list_lock); |
36409f63 MS |
798 | table = (unsigned long *) (__pa(table) | (bit << 4)); |
799 | tlb_remove_table(tlb, table); | |
800 | } | |
801 | ||
802 | void __tlb_remove_table(void *_table) | |
803 | { | |
e73b7fff MS |
804 | const unsigned long mask = (FRAG_MASK << 4) | FRAG_MASK; |
805 | void *table = (void *)((unsigned long) _table & ~mask); | |
806 | unsigned type = (unsigned long) _table & mask; | |
36409f63 MS |
807 | |
808 | if (type) | |
809 | __page_table_free_rcu(table, type); | |
810 | else | |
811 | free_pages((unsigned long) table, ALLOC_ORDER); | |
80217147 MS |
812 | } |
813 | ||
cd94154c MS |
814 | static void tlb_remove_table_smp_sync(void *arg) |
815 | { | |
816 | /* Simply deliver the interrupt */ | |
817 | } | |
818 | ||
819 | static void tlb_remove_table_one(void *table) | |
820 | { | |
821 | /* | |
822 | * This isn't an RCU grace period and hence the page-tables cannot be | |
823 | * assumed to be actually RCU-freed. | |
824 | * | |
825 | * It is however sufficient for software page-table walkers that rely | |
826 | * on IRQ disabling. See the comment near struct mmu_table_batch. | |
827 | */ | |
828 | smp_call_function(tlb_remove_table_smp_sync, NULL, 1); | |
829 | __tlb_remove_table(table); | |
830 | } | |
831 | ||
832 | static void tlb_remove_table_rcu(struct rcu_head *head) | |
833 | { | |
834 | struct mmu_table_batch *batch; | |
835 | int i; | |
836 | ||
837 | batch = container_of(head, struct mmu_table_batch, rcu); | |
838 | ||
839 | for (i = 0; i < batch->nr; i++) | |
840 | __tlb_remove_table(batch->tables[i]); | |
841 | ||
842 | free_page((unsigned long)batch); | |
843 | } | |
844 | ||
845 | void tlb_table_flush(struct mmu_gather *tlb) | |
846 | { | |
847 | struct mmu_table_batch **batch = &tlb->batch; | |
848 | ||
849 | if (*batch) { | |
850 | __tlb_flush_mm(tlb->mm); | |
851 | call_rcu_sched(&(*batch)->rcu, tlb_remove_table_rcu); | |
852 | *batch = NULL; | |
853 | } | |
854 | } | |
855 | ||
856 | void tlb_remove_table(struct mmu_gather *tlb, void *table) | |
857 | { | |
858 | struct mmu_table_batch **batch = &tlb->batch; | |
859 | ||
860 | if (*batch == NULL) { | |
861 | *batch = (struct mmu_table_batch *) | |
862 | __get_free_page(GFP_NOWAIT | __GFP_NOWARN); | |
863 | if (*batch == NULL) { | |
864 | __tlb_flush_mm(tlb->mm); | |
865 | tlb_remove_table_one(table); | |
866 | return; | |
867 | } | |
868 | (*batch)->nr = 0; | |
869 | } | |
870 | (*batch)->tables[(*batch)->nr++] = table; | |
871 | if ((*batch)->nr == MAX_TABLE_BATCH) | |
872 | tlb_table_flush(tlb); | |
873 | } | |
36409f63 | 874 | |
274023da GS |
875 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
876 | void thp_split_vma(struct vm_area_struct *vma) | |
877 | { | |
878 | unsigned long addr; | |
879 | struct page *page; | |
880 | ||
881 | for (addr = vma->vm_start; addr < vma->vm_end; addr += PAGE_SIZE) { | |
882 | page = follow_page(vma, addr, FOLL_SPLIT); | |
883 | } | |
884 | } | |
885 | ||
886 | void thp_split_mm(struct mm_struct *mm) | |
887 | { | |
888 | struct vm_area_struct *vma = mm->mmap; | |
889 | ||
890 | while (vma != NULL) { | |
891 | thp_split_vma(vma); | |
892 | vma->vm_flags &= ~VM_HUGEPAGE; | |
893 | vma->vm_flags |= VM_NOHUGEPAGE; | |
894 | vma = vma->vm_next; | |
895 | } | |
896 | } | |
897 | #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ | |
898 | ||
402b0862 CO |
899 | /* |
900 | * switch on pgstes for its userspace process (for kvm) | |
901 | */ | |
902 | int s390_enable_sie(void) | |
903 | { | |
904 | struct task_struct *tsk = current; | |
74b6b522 | 905 | struct mm_struct *mm, *old_mm; |
402b0862 | 906 | |
702d9e58 | 907 | /* Do we have switched amode? If no, we cannot do sie */ |
d1b0d842 | 908 | if (s390_user_mode == HOME_SPACE_MODE) |
702d9e58 CO |
909 | return -EINVAL; |
910 | ||
74b6b522 | 911 | /* Do we have pgstes? if yes, we are done */ |
36409f63 | 912 | if (mm_has_pgste(tsk->mm)) |
74b6b522 | 913 | return 0; |
402b0862 | 914 | |
74b6b522 CB |
915 | /* lets check if we are allowed to replace the mm */ |
916 | task_lock(tsk); | |
402b0862 | 917 | if (!tsk->mm || atomic_read(&tsk->mm->mm_users) > 1 || |
52a21f2c MS |
918 | #ifdef CONFIG_AIO |
919 | !hlist_empty(&tsk->mm->ioctx_list) || | |
920 | #endif | |
921 | tsk->mm != tsk->active_mm) { | |
74b6b522 CB |
922 | task_unlock(tsk); |
923 | return -EINVAL; | |
924 | } | |
925 | task_unlock(tsk); | |
402b0862 | 926 | |
250cf776 CB |
927 | /* we copy the mm and let dup_mm create the page tables with_pgstes */ |
928 | tsk->mm->context.alloc_pgste = 1; | |
2739b6d1 CB |
929 | /* make sure that both mms have a correct rss state */ |
930 | sync_mm_rss(tsk->mm); | |
402b0862 | 931 | mm = dup_mm(tsk); |
250cf776 | 932 | tsk->mm->context.alloc_pgste = 0; |
402b0862 | 933 | if (!mm) |
74b6b522 CB |
934 | return -ENOMEM; |
935 | ||
274023da GS |
936 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
937 | /* split thp mappings and disable thp for future mappings */ | |
938 | thp_split_mm(mm); | |
939 | mm->def_flags |= VM_NOHUGEPAGE; | |
940 | #endif | |
941 | ||
250cf776 | 942 | /* Now lets check again if something happened */ |
74b6b522 CB |
943 | task_lock(tsk); |
944 | if (!tsk->mm || atomic_read(&tsk->mm->mm_users) > 1 || | |
52a21f2c MS |
945 | #ifdef CONFIG_AIO |
946 | !hlist_empty(&tsk->mm->ioctx_list) || | |
947 | #endif | |
948 | tsk->mm != tsk->active_mm) { | |
74b6b522 CB |
949 | mmput(mm); |
950 | task_unlock(tsk); | |
951 | return -EINVAL; | |
952 | } | |
953 | ||
954 | /* ok, we are alone. No ptrace, no threads, etc. */ | |
955 | old_mm = tsk->mm; | |
402b0862 CO |
956 | tsk->mm = tsk->active_mm = mm; |
957 | preempt_disable(); | |
958 | update_mm(mm, tsk); | |
e05ef9bd CB |
959 | atomic_inc(&mm->context.attach_count); |
960 | atomic_dec(&old_mm->context.attach_count); | |
005f8eee | 961 | cpumask_set_cpu(smp_processor_id(), mm_cpumask(mm)); |
402b0862 | 962 | preempt_enable(); |
402b0862 | 963 | task_unlock(tsk); |
74b6b522 CB |
964 | mmput(old_mm); |
965 | return 0; | |
402b0862 CO |
966 | } |
967 | EXPORT_SYMBOL_GPL(s390_enable_sie); | |
7db11a36 | 968 | |
75077afb | 969 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
1ae1c1d0 GS |
970 | int pmdp_clear_flush_young(struct vm_area_struct *vma, unsigned long address, |
971 | pmd_t *pmdp) | |
972 | { | |
973 | VM_BUG_ON(address & ~HPAGE_PMD_MASK); | |
974 | /* No need to flush TLB | |
975 | * On s390 reference bits are in storage key and never in TLB */ | |
976 | return pmdp_test_and_clear_young(vma, address, pmdp); | |
977 | } | |
978 | ||
979 | int pmdp_set_access_flags(struct vm_area_struct *vma, | |
980 | unsigned long address, pmd_t *pmdp, | |
981 | pmd_t entry, int dirty) | |
982 | { | |
983 | VM_BUG_ON(address & ~HPAGE_PMD_MASK); | |
984 | ||
985 | if (pmd_same(*pmdp, entry)) | |
986 | return 0; | |
987 | pmdp_invalidate(vma, address, pmdp); | |
988 | set_pmd_at(vma->vm_mm, address, pmdp, entry); | |
989 | return 1; | |
990 | } | |
991 | ||
75077afb GS |
992 | static void pmdp_splitting_flush_sync(void *arg) |
993 | { | |
994 | /* Simply deliver the interrupt */ | |
995 | } | |
996 | ||
997 | void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address, | |
998 | pmd_t *pmdp) | |
999 | { | |
1000 | VM_BUG_ON(address & ~HPAGE_PMD_MASK); | |
1001 | if (!test_and_set_bit(_SEGMENT_ENTRY_SPLIT_BIT, | |
1002 | (unsigned long *) pmdp)) { | |
1003 | /* need to serialize against gup-fast (IRQ disabled) */ | |
1004 | smp_call_function(pmdp_splitting_flush_sync, NULL, 1); | |
1005 | } | |
1006 | } | |
9501d09f GS |
1007 | |
1008 | void pgtable_trans_huge_deposit(struct mm_struct *mm, pgtable_t pgtable) | |
1009 | { | |
1010 | struct list_head *lh = (struct list_head *) pgtable; | |
1011 | ||
1012 | assert_spin_locked(&mm->page_table_lock); | |
1013 | ||
1014 | /* FIFO */ | |
1015 | if (!mm->pmd_huge_pte) | |
1016 | INIT_LIST_HEAD(lh); | |
1017 | else | |
1018 | list_add(lh, (struct list_head *) mm->pmd_huge_pte); | |
1019 | mm->pmd_huge_pte = pgtable; | |
1020 | } | |
1021 | ||
1022 | pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm) | |
1023 | { | |
1024 | struct list_head *lh; | |
1025 | pgtable_t pgtable; | |
1026 | pte_t *ptep; | |
1027 | ||
1028 | assert_spin_locked(&mm->page_table_lock); | |
1029 | ||
1030 | /* FIFO */ | |
1031 | pgtable = mm->pmd_huge_pte; | |
1032 | lh = (struct list_head *) pgtable; | |
1033 | if (list_empty(lh)) | |
1034 | mm->pmd_huge_pte = NULL; | |
1035 | else { | |
1036 | mm->pmd_huge_pte = (pgtable_t) lh->next; | |
1037 | list_del(lh); | |
1038 | } | |
1039 | ptep = (pte_t *) pgtable; | |
1040 | pte_val(*ptep) = _PAGE_TYPE_EMPTY; | |
1041 | ptep++; | |
1042 | pte_val(*ptep) = _PAGE_TYPE_EMPTY; | |
1043 | return pgtable; | |
1044 | } | |
75077afb | 1045 | #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |