Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Generic hugetlb support. | |
3 | * (C) William Irwin, April 2004 | |
4 | */ | |
5 | #include <linux/gfp.h> | |
6 | #include <linux/list.h> | |
7 | #include <linux/init.h> | |
8 | #include <linux/module.h> | |
9 | #include <linux/mm.h> | |
1da177e4 LT |
10 | #include <linux/sysctl.h> |
11 | #include <linux/highmem.h> | |
12 | #include <linux/nodemask.h> | |
63551ae0 | 13 | #include <linux/pagemap.h> |
5da7ca86 | 14 | #include <linux/mempolicy.h> |
aea47ff3 | 15 | #include <linux/cpuset.h> |
5da7ca86 | 16 | |
63551ae0 DG |
17 | #include <asm/page.h> |
18 | #include <asm/pgtable.h> | |
19 | ||
20 | #include <linux/hugetlb.h> | |
7835e98b | 21 | #include "internal.h" |
1da177e4 LT |
22 | |
23 | const unsigned long hugetlb_zero = 0, hugetlb_infinity = ~0UL; | |
24 | static unsigned long nr_huge_pages, free_huge_pages; | |
25 | unsigned long max_huge_pages; | |
26 | static struct list_head hugepage_freelists[MAX_NUMNODES]; | |
27 | static unsigned int nr_huge_pages_node[MAX_NUMNODES]; | |
28 | static unsigned int free_huge_pages_node[MAX_NUMNODES]; | |
0bd0f9fb | 29 | |
79ac6ba4 DG |
30 | static void clear_huge_page(struct page *page, unsigned long addr) |
31 | { | |
32 | int i; | |
33 | ||
34 | might_sleep(); | |
35 | for (i = 0; i < (HPAGE_SIZE/PAGE_SIZE); i++) { | |
36 | cond_resched(); | |
37 | clear_user_highpage(page + i, addr); | |
38 | } | |
39 | } | |
40 | ||
41 | static void copy_huge_page(struct page *dst, struct page *src, | |
42 | unsigned long addr) | |
43 | { | |
44 | int i; | |
45 | ||
46 | might_sleep(); | |
47 | for (i = 0; i < HPAGE_SIZE/PAGE_SIZE; i++) { | |
48 | cond_resched(); | |
49 | copy_user_highpage(dst + i, src + i, addr + i*PAGE_SIZE); | |
50 | } | |
51 | } | |
52 | ||
0bd0f9fb EP |
53 | /* |
54 | * Protects updates to hugepage_freelists, nr_huge_pages, and free_huge_pages | |
55 | */ | |
1da177e4 LT |
56 | static DEFINE_SPINLOCK(hugetlb_lock); |
57 | ||
58 | static void enqueue_huge_page(struct page *page) | |
59 | { | |
60 | int nid = page_to_nid(page); | |
61 | list_add(&page->lru, &hugepage_freelists[nid]); | |
62 | free_huge_pages++; | |
63 | free_huge_pages_node[nid]++; | |
64 | } | |
65 | ||
5da7ca86 CL |
66 | static struct page *dequeue_huge_page(struct vm_area_struct *vma, |
67 | unsigned long address) | |
1da177e4 LT |
68 | { |
69 | int nid = numa_node_id(); | |
70 | struct page *page = NULL; | |
5da7ca86 | 71 | struct zonelist *zonelist = huge_zonelist(vma, address); |
96df9333 | 72 | struct zone **z; |
1da177e4 | 73 | |
96df9333 CL |
74 | for (z = zonelist->zones; *z; z++) { |
75 | nid = (*z)->zone_pgdat->node_id; | |
aea47ff3 CL |
76 | if (cpuset_zone_allowed(*z, GFP_HIGHUSER) && |
77 | !list_empty(&hugepage_freelists[nid])) | |
96df9333 | 78 | break; |
1da177e4 | 79 | } |
96df9333 CL |
80 | |
81 | if (*z) { | |
1da177e4 LT |
82 | page = list_entry(hugepage_freelists[nid].next, |
83 | struct page, lru); | |
84 | list_del(&page->lru); | |
85 | free_huge_pages--; | |
86 | free_huge_pages_node[nid]--; | |
87 | } | |
88 | return page; | |
89 | } | |
90 | ||
a482289d | 91 | static int alloc_fresh_huge_page(void) |
1da177e4 LT |
92 | { |
93 | static int nid = 0; | |
94 | struct page *page; | |
95 | page = alloc_pages_node(nid, GFP_HIGHUSER|__GFP_COMP|__GFP_NOWARN, | |
96 | HUGETLB_PAGE_ORDER); | |
97 | nid = (nid + 1) % num_online_nodes(); | |
98 | if (page) { | |
a482289d | 99 | page[1].lru.next = (void *)free_huge_page; /* dtor */ |
0bd0f9fb | 100 | spin_lock(&hugetlb_lock); |
1da177e4 LT |
101 | nr_huge_pages++; |
102 | nr_huge_pages_node[page_to_nid(page)]++; | |
0bd0f9fb | 103 | spin_unlock(&hugetlb_lock); |
a482289d NP |
104 | put_page(page); /* free it into the hugepage allocator */ |
105 | return 1; | |
1da177e4 | 106 | } |
a482289d | 107 | return 0; |
1da177e4 LT |
108 | } |
109 | ||
110 | void free_huge_page(struct page *page) | |
111 | { | |
112 | BUG_ON(page_count(page)); | |
113 | ||
114 | INIT_LIST_HEAD(&page->lru); | |
1da177e4 LT |
115 | |
116 | spin_lock(&hugetlb_lock); | |
117 | enqueue_huge_page(page); | |
118 | spin_unlock(&hugetlb_lock); | |
119 | } | |
120 | ||
5da7ca86 | 121 | struct page *alloc_huge_page(struct vm_area_struct *vma, unsigned long addr) |
1da177e4 LT |
122 | { |
123 | struct page *page; | |
1da177e4 LT |
124 | |
125 | spin_lock(&hugetlb_lock); | |
5da7ca86 | 126 | page = dequeue_huge_page(vma, addr); |
1da177e4 LT |
127 | if (!page) { |
128 | spin_unlock(&hugetlb_lock); | |
129 | return NULL; | |
130 | } | |
131 | spin_unlock(&hugetlb_lock); | |
7835e98b | 132 | set_page_refcounted(page); |
1da177e4 LT |
133 | return page; |
134 | } | |
135 | ||
136 | static int __init hugetlb_init(void) | |
137 | { | |
138 | unsigned long i; | |
1da177e4 | 139 | |
3c726f8d BH |
140 | if (HPAGE_SHIFT == 0) |
141 | return 0; | |
142 | ||
1da177e4 LT |
143 | for (i = 0; i < MAX_NUMNODES; ++i) |
144 | INIT_LIST_HEAD(&hugepage_freelists[i]); | |
145 | ||
146 | for (i = 0; i < max_huge_pages; ++i) { | |
a482289d | 147 | if (!alloc_fresh_huge_page()) |
1da177e4 | 148 | break; |
1da177e4 LT |
149 | } |
150 | max_huge_pages = free_huge_pages = nr_huge_pages = i; | |
151 | printk("Total HugeTLB memory allocated, %ld\n", free_huge_pages); | |
152 | return 0; | |
153 | } | |
154 | module_init(hugetlb_init); | |
155 | ||
156 | static int __init hugetlb_setup(char *s) | |
157 | { | |
158 | if (sscanf(s, "%lu", &max_huge_pages) <= 0) | |
159 | max_huge_pages = 0; | |
160 | return 1; | |
161 | } | |
162 | __setup("hugepages=", hugetlb_setup); | |
163 | ||
164 | #ifdef CONFIG_SYSCTL | |
165 | static void update_and_free_page(struct page *page) | |
166 | { | |
167 | int i; | |
168 | nr_huge_pages--; | |
169 | nr_huge_pages_node[page_zone(page)->zone_pgdat->node_id]--; | |
170 | for (i = 0; i < (HPAGE_SIZE / PAGE_SIZE); i++) { | |
171 | page[i].flags &= ~(1 << PG_locked | 1 << PG_error | 1 << PG_referenced | | |
172 | 1 << PG_dirty | 1 << PG_active | 1 << PG_reserved | | |
173 | 1 << PG_private | 1<< PG_writeback); | |
1da177e4 | 174 | } |
a482289d | 175 | page[1].lru.next = NULL; |
7835e98b | 176 | set_page_refcounted(page); |
1da177e4 LT |
177 | __free_pages(page, HUGETLB_PAGE_ORDER); |
178 | } | |
179 | ||
180 | #ifdef CONFIG_HIGHMEM | |
181 | static void try_to_free_low(unsigned long count) | |
182 | { | |
183 | int i, nid; | |
184 | for (i = 0; i < MAX_NUMNODES; ++i) { | |
185 | struct page *page, *next; | |
186 | list_for_each_entry_safe(page, next, &hugepage_freelists[i], lru) { | |
187 | if (PageHighMem(page)) | |
188 | continue; | |
189 | list_del(&page->lru); | |
190 | update_and_free_page(page); | |
191 | nid = page_zone(page)->zone_pgdat->node_id; | |
192 | free_huge_pages--; | |
193 | free_huge_pages_node[nid]--; | |
194 | if (count >= nr_huge_pages) | |
195 | return; | |
196 | } | |
197 | } | |
198 | } | |
199 | #else | |
200 | static inline void try_to_free_low(unsigned long count) | |
201 | { | |
202 | } | |
203 | #endif | |
204 | ||
205 | static unsigned long set_max_huge_pages(unsigned long count) | |
206 | { | |
207 | while (count > nr_huge_pages) { | |
a482289d | 208 | if (!alloc_fresh_huge_page()) |
1da177e4 | 209 | return nr_huge_pages; |
1da177e4 LT |
210 | } |
211 | if (count >= nr_huge_pages) | |
212 | return nr_huge_pages; | |
213 | ||
214 | spin_lock(&hugetlb_lock); | |
215 | try_to_free_low(count); | |
216 | while (count < nr_huge_pages) { | |
5da7ca86 | 217 | struct page *page = dequeue_huge_page(NULL, 0); |
1da177e4 LT |
218 | if (!page) |
219 | break; | |
220 | update_and_free_page(page); | |
221 | } | |
222 | spin_unlock(&hugetlb_lock); | |
223 | return nr_huge_pages; | |
224 | } | |
225 | ||
226 | int hugetlb_sysctl_handler(struct ctl_table *table, int write, | |
227 | struct file *file, void __user *buffer, | |
228 | size_t *length, loff_t *ppos) | |
229 | { | |
230 | proc_doulongvec_minmax(table, write, file, buffer, length, ppos); | |
231 | max_huge_pages = set_max_huge_pages(max_huge_pages); | |
232 | return 0; | |
233 | } | |
234 | #endif /* CONFIG_SYSCTL */ | |
235 | ||
236 | int hugetlb_report_meminfo(char *buf) | |
237 | { | |
238 | return sprintf(buf, | |
239 | "HugePages_Total: %5lu\n" | |
240 | "HugePages_Free: %5lu\n" | |
241 | "Hugepagesize: %5lu kB\n", | |
242 | nr_huge_pages, | |
243 | free_huge_pages, | |
244 | HPAGE_SIZE/1024); | |
245 | } | |
246 | ||
247 | int hugetlb_report_node_meminfo(int nid, char *buf) | |
248 | { | |
249 | return sprintf(buf, | |
250 | "Node %d HugePages_Total: %5u\n" | |
251 | "Node %d HugePages_Free: %5u\n", | |
252 | nid, nr_huge_pages_node[nid], | |
253 | nid, free_huge_pages_node[nid]); | |
254 | } | |
255 | ||
256 | int is_hugepage_mem_enough(size_t size) | |
257 | { | |
258 | return (size + ~HPAGE_MASK)/HPAGE_SIZE <= free_huge_pages; | |
259 | } | |
260 | ||
261 | /* Return the number pages of memory we physically have, in PAGE_SIZE units. */ | |
262 | unsigned long hugetlb_total_pages(void) | |
263 | { | |
264 | return nr_huge_pages * (HPAGE_SIZE / PAGE_SIZE); | |
265 | } | |
1da177e4 LT |
266 | |
267 | /* | |
268 | * We cannot handle pagefaults against hugetlb pages at all. They cause | |
269 | * handle_mm_fault() to try to instantiate regular-sized pages in the | |
270 | * hugegpage VMA. do_page_fault() is supposed to trap this, so BUG is we get | |
271 | * this far. | |
272 | */ | |
273 | static struct page *hugetlb_nopage(struct vm_area_struct *vma, | |
274 | unsigned long address, int *unused) | |
275 | { | |
276 | BUG(); | |
277 | return NULL; | |
278 | } | |
279 | ||
280 | struct vm_operations_struct hugetlb_vm_ops = { | |
281 | .nopage = hugetlb_nopage, | |
282 | }; | |
283 | ||
1e8f889b DG |
284 | static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page, |
285 | int writable) | |
63551ae0 DG |
286 | { |
287 | pte_t entry; | |
288 | ||
1e8f889b | 289 | if (writable) { |
63551ae0 DG |
290 | entry = |
291 | pte_mkwrite(pte_mkdirty(mk_pte(page, vma->vm_page_prot))); | |
292 | } else { | |
293 | entry = pte_wrprotect(mk_pte(page, vma->vm_page_prot)); | |
294 | } | |
295 | entry = pte_mkyoung(entry); | |
296 | entry = pte_mkhuge(entry); | |
297 | ||
298 | return entry; | |
299 | } | |
300 | ||
1e8f889b DG |
301 | static void set_huge_ptep_writable(struct vm_area_struct *vma, |
302 | unsigned long address, pte_t *ptep) | |
303 | { | |
304 | pte_t entry; | |
305 | ||
306 | entry = pte_mkwrite(pte_mkdirty(*ptep)); | |
307 | ptep_set_access_flags(vma, address, ptep, entry, 1); | |
308 | update_mmu_cache(vma, address, entry); | |
309 | lazy_mmu_prot_update(entry); | |
310 | } | |
311 | ||
312 | ||
63551ae0 DG |
313 | int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, |
314 | struct vm_area_struct *vma) | |
315 | { | |
316 | pte_t *src_pte, *dst_pte, entry; | |
317 | struct page *ptepage; | |
1c59827d | 318 | unsigned long addr; |
1e8f889b DG |
319 | int cow; |
320 | ||
321 | cow = (vma->vm_flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE; | |
63551ae0 | 322 | |
1c59827d | 323 | for (addr = vma->vm_start; addr < vma->vm_end; addr += HPAGE_SIZE) { |
c74df32c HD |
324 | src_pte = huge_pte_offset(src, addr); |
325 | if (!src_pte) | |
326 | continue; | |
63551ae0 DG |
327 | dst_pte = huge_pte_alloc(dst, addr); |
328 | if (!dst_pte) | |
329 | goto nomem; | |
c74df32c | 330 | spin_lock(&dst->page_table_lock); |
1c59827d | 331 | spin_lock(&src->page_table_lock); |
c74df32c | 332 | if (!pte_none(*src_pte)) { |
1e8f889b DG |
333 | if (cow) |
334 | ptep_set_wrprotect(src, addr, src_pte); | |
1c59827d HD |
335 | entry = *src_pte; |
336 | ptepage = pte_page(entry); | |
337 | get_page(ptepage); | |
4294621f | 338 | add_mm_counter(dst, file_rss, HPAGE_SIZE / PAGE_SIZE); |
1c59827d HD |
339 | set_huge_pte_at(dst, addr, dst_pte, entry); |
340 | } | |
341 | spin_unlock(&src->page_table_lock); | |
c74df32c | 342 | spin_unlock(&dst->page_table_lock); |
63551ae0 DG |
343 | } |
344 | return 0; | |
345 | ||
346 | nomem: | |
347 | return -ENOMEM; | |
348 | } | |
349 | ||
350 | void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, | |
351 | unsigned long end) | |
352 | { | |
353 | struct mm_struct *mm = vma->vm_mm; | |
354 | unsigned long address; | |
c7546f8f | 355 | pte_t *ptep; |
63551ae0 DG |
356 | pte_t pte; |
357 | struct page *page; | |
358 | ||
359 | WARN_ON(!is_vm_hugetlb_page(vma)); | |
360 | BUG_ON(start & ~HPAGE_MASK); | |
361 | BUG_ON(end & ~HPAGE_MASK); | |
362 | ||
508034a3 HD |
363 | spin_lock(&mm->page_table_lock); |
364 | ||
365e9c87 HD |
365 | /* Update high watermark before we lower rss */ |
366 | update_hiwater_rss(mm); | |
367 | ||
63551ae0 | 368 | for (address = start; address < end; address += HPAGE_SIZE) { |
c7546f8f | 369 | ptep = huge_pte_offset(mm, address); |
4c887265 | 370 | if (!ptep) |
c7546f8f DG |
371 | continue; |
372 | ||
373 | pte = huge_ptep_get_and_clear(mm, address, ptep); | |
63551ae0 DG |
374 | if (pte_none(pte)) |
375 | continue; | |
c7546f8f | 376 | |
63551ae0 DG |
377 | page = pte_page(pte); |
378 | put_page(page); | |
4294621f | 379 | add_mm_counter(mm, file_rss, (int) -(HPAGE_SIZE / PAGE_SIZE)); |
63551ae0 | 380 | } |
63551ae0 | 381 | |
1da177e4 | 382 | spin_unlock(&mm->page_table_lock); |
508034a3 | 383 | flush_tlb_range(vma, start, end); |
1da177e4 | 384 | } |
63551ae0 | 385 | |
1e8f889b DG |
386 | static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma, |
387 | unsigned long address, pte_t *ptep, pte_t pte) | |
388 | { | |
389 | struct page *old_page, *new_page; | |
79ac6ba4 | 390 | int avoidcopy; |
1e8f889b DG |
391 | |
392 | old_page = pte_page(pte); | |
393 | ||
394 | /* If no-one else is actually using this page, avoid the copy | |
395 | * and just make the page writable */ | |
396 | avoidcopy = (page_count(old_page) == 1); | |
397 | if (avoidcopy) { | |
398 | set_huge_ptep_writable(vma, address, ptep); | |
399 | return VM_FAULT_MINOR; | |
400 | } | |
401 | ||
402 | page_cache_get(old_page); | |
5da7ca86 | 403 | new_page = alloc_huge_page(vma, address); |
1e8f889b DG |
404 | |
405 | if (!new_page) { | |
406 | page_cache_release(old_page); | |
0df420d8 | 407 | return VM_FAULT_OOM; |
1e8f889b DG |
408 | } |
409 | ||
410 | spin_unlock(&mm->page_table_lock); | |
79ac6ba4 | 411 | copy_huge_page(new_page, old_page, address); |
1e8f889b DG |
412 | spin_lock(&mm->page_table_lock); |
413 | ||
414 | ptep = huge_pte_offset(mm, address & HPAGE_MASK); | |
415 | if (likely(pte_same(*ptep, pte))) { | |
416 | /* Break COW */ | |
417 | set_huge_pte_at(mm, address, ptep, | |
418 | make_huge_pte(vma, new_page, 1)); | |
419 | /* Make the old page be freed below */ | |
420 | new_page = old_page; | |
421 | } | |
422 | page_cache_release(new_page); | |
423 | page_cache_release(old_page); | |
424 | return VM_FAULT_MINOR; | |
425 | } | |
426 | ||
86e5216f | 427 | int hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma, |
1e8f889b | 428 | unsigned long address, pte_t *ptep, int write_access) |
ac9b9c66 HD |
429 | { |
430 | int ret = VM_FAULT_SIGBUS; | |
4c887265 AL |
431 | unsigned long idx; |
432 | unsigned long size; | |
4c887265 AL |
433 | struct page *page; |
434 | struct address_space *mapping; | |
1e8f889b | 435 | pte_t new_pte; |
4c887265 | 436 | |
4c887265 AL |
437 | mapping = vma->vm_file->f_mapping; |
438 | idx = ((address - vma->vm_start) >> HPAGE_SHIFT) | |
439 | + (vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT)); | |
440 | ||
441 | /* | |
442 | * Use page lock to guard against racing truncation | |
443 | * before we get page_table_lock. | |
444 | */ | |
6bda666a CL |
445 | retry: |
446 | page = find_lock_page(mapping, idx); | |
447 | if (!page) { | |
448 | if (hugetlb_get_quota(mapping)) | |
449 | goto out; | |
450 | page = alloc_huge_page(vma, address); | |
451 | if (!page) { | |
452 | hugetlb_put_quota(mapping); | |
0df420d8 | 453 | ret = VM_FAULT_OOM; |
6bda666a CL |
454 | goto out; |
455 | } | |
79ac6ba4 | 456 | clear_huge_page(page, address); |
ac9b9c66 | 457 | |
6bda666a CL |
458 | if (vma->vm_flags & VM_SHARED) { |
459 | int err; | |
460 | ||
461 | err = add_to_page_cache(page, mapping, idx, GFP_KERNEL); | |
462 | if (err) { | |
463 | put_page(page); | |
464 | hugetlb_put_quota(mapping); | |
465 | if (err == -EEXIST) | |
466 | goto retry; | |
467 | goto out; | |
468 | } | |
469 | } else | |
470 | lock_page(page); | |
471 | } | |
1e8f889b | 472 | |
ac9b9c66 | 473 | spin_lock(&mm->page_table_lock); |
4c887265 AL |
474 | size = i_size_read(mapping->host) >> HPAGE_SHIFT; |
475 | if (idx >= size) | |
476 | goto backout; | |
477 | ||
478 | ret = VM_FAULT_MINOR; | |
86e5216f | 479 | if (!pte_none(*ptep)) |
4c887265 AL |
480 | goto backout; |
481 | ||
482 | add_mm_counter(mm, file_rss, HPAGE_SIZE / PAGE_SIZE); | |
1e8f889b DG |
483 | new_pte = make_huge_pte(vma, page, ((vma->vm_flags & VM_WRITE) |
484 | && (vma->vm_flags & VM_SHARED))); | |
485 | set_huge_pte_at(mm, address, ptep, new_pte); | |
486 | ||
487 | if (write_access && !(vma->vm_flags & VM_SHARED)) { | |
488 | /* Optimization, do the COW without a second fault */ | |
489 | ret = hugetlb_cow(mm, vma, address, ptep, new_pte); | |
490 | } | |
491 | ||
ac9b9c66 | 492 | spin_unlock(&mm->page_table_lock); |
4c887265 AL |
493 | unlock_page(page); |
494 | out: | |
ac9b9c66 | 495 | return ret; |
4c887265 AL |
496 | |
497 | backout: | |
498 | spin_unlock(&mm->page_table_lock); | |
499 | hugetlb_put_quota(mapping); | |
500 | unlock_page(page); | |
501 | put_page(page); | |
502 | goto out; | |
ac9b9c66 HD |
503 | } |
504 | ||
86e5216f AL |
505 | int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, |
506 | unsigned long address, int write_access) | |
507 | { | |
508 | pte_t *ptep; | |
509 | pte_t entry; | |
1e8f889b | 510 | int ret; |
86e5216f AL |
511 | |
512 | ptep = huge_pte_alloc(mm, address); | |
513 | if (!ptep) | |
514 | return VM_FAULT_OOM; | |
515 | ||
516 | entry = *ptep; | |
517 | if (pte_none(entry)) | |
1e8f889b | 518 | return hugetlb_no_page(mm, vma, address, ptep, write_access); |
86e5216f | 519 | |
1e8f889b DG |
520 | ret = VM_FAULT_MINOR; |
521 | ||
522 | spin_lock(&mm->page_table_lock); | |
523 | /* Check for a racing update before calling hugetlb_cow */ | |
524 | if (likely(pte_same(entry, *ptep))) | |
525 | if (write_access && !pte_write(entry)) | |
526 | ret = hugetlb_cow(mm, vma, address, ptep, entry); | |
527 | spin_unlock(&mm->page_table_lock); | |
528 | ||
529 | return ret; | |
86e5216f AL |
530 | } |
531 | ||
63551ae0 DG |
532 | int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, |
533 | struct page **pages, struct vm_area_struct **vmas, | |
534 | unsigned long *position, int *length, int i) | |
535 | { | |
536 | unsigned long vpfn, vaddr = *position; | |
537 | int remainder = *length; | |
538 | ||
63551ae0 | 539 | vpfn = vaddr/PAGE_SIZE; |
1c59827d | 540 | spin_lock(&mm->page_table_lock); |
63551ae0 | 541 | while (vaddr < vma->vm_end && remainder) { |
4c887265 AL |
542 | pte_t *pte; |
543 | struct page *page; | |
63551ae0 | 544 | |
4c887265 AL |
545 | /* |
546 | * Some archs (sparc64, sh*) have multiple pte_ts to | |
547 | * each hugepage. We have to make * sure we get the | |
548 | * first, for the page indexing below to work. | |
549 | */ | |
550 | pte = huge_pte_offset(mm, vaddr & HPAGE_MASK); | |
63551ae0 | 551 | |
4c887265 AL |
552 | if (!pte || pte_none(*pte)) { |
553 | int ret; | |
63551ae0 | 554 | |
4c887265 AL |
555 | spin_unlock(&mm->page_table_lock); |
556 | ret = hugetlb_fault(mm, vma, vaddr, 0); | |
557 | spin_lock(&mm->page_table_lock); | |
558 | if (ret == VM_FAULT_MINOR) | |
559 | continue; | |
63551ae0 | 560 | |
4c887265 AL |
561 | remainder = 0; |
562 | if (!i) | |
563 | i = -EFAULT; | |
564 | break; | |
565 | } | |
566 | ||
567 | if (pages) { | |
568 | page = &pte_page(*pte)[vpfn % (HPAGE_SIZE/PAGE_SIZE)]; | |
63551ae0 DG |
569 | get_page(page); |
570 | pages[i] = page; | |
571 | } | |
572 | ||
573 | if (vmas) | |
574 | vmas[i] = vma; | |
575 | ||
576 | vaddr += PAGE_SIZE; | |
577 | ++vpfn; | |
578 | --remainder; | |
579 | ++i; | |
580 | } | |
1c59827d | 581 | spin_unlock(&mm->page_table_lock); |
63551ae0 DG |
582 | *length = remainder; |
583 | *position = vaddr; | |
584 | ||
585 | return i; | |
586 | } | |
8f860591 ZY |
587 | |
588 | void hugetlb_change_protection(struct vm_area_struct *vma, | |
589 | unsigned long address, unsigned long end, pgprot_t newprot) | |
590 | { | |
591 | struct mm_struct *mm = vma->vm_mm; | |
592 | unsigned long start = address; | |
593 | pte_t *ptep; | |
594 | pte_t pte; | |
595 | ||
596 | BUG_ON(address >= end); | |
597 | flush_cache_range(vma, address, end); | |
598 | ||
599 | spin_lock(&mm->page_table_lock); | |
600 | for (; address < end; address += HPAGE_SIZE) { | |
601 | ptep = huge_pte_offset(mm, address); | |
602 | if (!ptep) | |
603 | continue; | |
604 | if (!pte_none(*ptep)) { | |
605 | pte = huge_ptep_get_and_clear(mm, address, ptep); | |
606 | pte = pte_mkhuge(pte_modify(pte, newprot)); | |
607 | set_huge_pte_at(mm, address, ptep, pte); | |
608 | lazy_mmu_prot_update(pte); | |
609 | } | |
610 | } | |
611 | spin_unlock(&mm->page_table_lock); | |
612 | ||
613 | flush_tlb_range(vma, start, end); | |
614 | } | |
615 |