Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * PPC64 (POWER4) Huge TLB Page Support for Kernel. | |
3 | * | |
4 | * Copyright (C) 2003 David Gibson, IBM Corporation. | |
5 | * | |
6 | * Based on the IA-32 version: | |
7 | * Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com> | |
8 | */ | |
9 | ||
10 | #include <linux/init.h> | |
11 | #include <linux/fs.h> | |
12 | #include <linux/mm.h> | |
13 | #include <linux/hugetlb.h> | |
14 | #include <linux/pagemap.h> | |
1da177e4 LT |
15 | #include <linux/slab.h> |
16 | #include <linux/err.h> | |
17 | #include <linux/sysctl.h> | |
18 | #include <asm/mman.h> | |
19 | #include <asm/pgalloc.h> | |
20 | #include <asm/tlb.h> | |
21 | #include <asm/tlbflush.h> | |
22 | #include <asm/mmu_context.h> | |
23 | #include <asm/machdep.h> | |
24 | #include <asm/cputable.h> | |
94b2a439 | 25 | #include <asm/spu.h> |
1da177e4 | 26 | |
91224346 JT |
27 | #define PAGE_SHIFT_64K 16 |
28 | #define PAGE_SHIFT_16M 24 | |
29 | #define PAGE_SHIFT_16G 34 | |
4ec161cf | 30 | |
c594adad DG |
31 | #define NUM_LOW_AREAS (0x100000000UL >> SID_SHIFT) |
32 | #define NUM_HIGH_AREAS (PGTABLE_RANGE >> HTLB_AREA_SHIFT) | |
ec4b2c0c JT |
33 | #define MAX_NUMBER_GPAGES 1024 |
34 | ||
35 | /* Tracks the 16G pages after the device tree is scanned and before the | |
36 | * huge_boot_pages list is ready. */ | |
37 | static unsigned long gpage_freearray[MAX_NUMBER_GPAGES]; | |
38 | static unsigned nr_gpages; | |
c594adad | 39 | |
0d9ea754 JT |
40 | /* Array of valid huge page sizes - non-zero value(hugepte_shift) is |
41 | * stored for the huge page sizes that are valid. | |
42 | */ | |
43 | unsigned int mmu_huge_psizes[MMU_PAGE_COUNT] = { }; /* initialize all to 0 */ | |
44 | ||
45 | #define hugepte_shift mmu_huge_psizes | |
a0668cdc DG |
46 | #define HUGEPTE_INDEX_SIZE(psize) (mmu_huge_psizes[(psize)]) |
47 | #define PTRS_PER_HUGEPTE(psize) (1 << mmu_huge_psizes[psize]) | |
0d9ea754 JT |
48 | |
49 | #define HUGEPD_SHIFT(psize) (mmu_psize_to_shift(psize) \ | |
a0668cdc | 50 | + HUGEPTE_INDEX_SIZE(psize)) |
0d9ea754 JT |
51 | #define HUGEPD_SIZE(psize) (1UL << HUGEPD_SHIFT(psize)) |
52 | #define HUGEPD_MASK(psize) (~(HUGEPD_SIZE(psize)-1)) | |
f10a04c0 | 53 | |
f10a04c0 DG |
54 | /* Flag to mark huge PD pointers. This means pmd_bad() and pud_bad() |
55 | * will choke on pointers to hugepte tables, which is handy for | |
56 | * catching screwups early. */ | |
57 | #define HUGEPD_OK 0x1 | |
58 | ||
59 | typedef struct { unsigned long pd; } hugepd_t; | |
60 | ||
61 | #define hugepd_none(hpd) ((hpd).pd == 0) | |
62 | ||
0d9ea754 JT |
63 | static inline int shift_to_mmu_psize(unsigned int shift) |
64 | { | |
65 | switch (shift) { | |
66 | #ifndef CONFIG_PPC_64K_PAGES | |
67 | case PAGE_SHIFT_64K: | |
68 | return MMU_PAGE_64K; | |
69 | #endif | |
70 | case PAGE_SHIFT_16M: | |
71 | return MMU_PAGE_16M; | |
72 | case PAGE_SHIFT_16G: | |
73 | return MMU_PAGE_16G; | |
74 | } | |
75 | return -1; | |
76 | } | |
77 | ||
78 | static inline unsigned int mmu_psize_to_shift(unsigned int mmu_psize) | |
79 | { | |
80 | if (mmu_psize_defs[mmu_psize].shift) | |
81 | return mmu_psize_defs[mmu_psize].shift; | |
82 | BUG(); | |
83 | } | |
84 | ||
f10a04c0 DG |
85 | static inline pte_t *hugepd_page(hugepd_t hpd) |
86 | { | |
87 | BUG_ON(!(hpd.pd & HUGEPD_OK)); | |
88 | return (pte_t *)(hpd.pd & ~HUGEPD_OK); | |
89 | } | |
90 | ||
0d9ea754 JT |
91 | static inline pte_t *hugepte_offset(hugepd_t *hpdp, unsigned long addr, |
92 | struct hstate *hstate) | |
f10a04c0 | 93 | { |
0d9ea754 JT |
94 | unsigned int shift = huge_page_shift(hstate); |
95 | int psize = shift_to_mmu_psize(shift); | |
96 | unsigned long idx = ((addr >> shift) & (PTRS_PER_HUGEPTE(psize)-1)); | |
f10a04c0 DG |
97 | pte_t *dir = hugepd_page(*hpdp); |
98 | ||
99 | return dir + idx; | |
100 | } | |
101 | ||
102 | static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp, | |
0d9ea754 | 103 | unsigned long address, unsigned int psize) |
f10a04c0 | 104 | { |
a0668cdc DG |
105 | pte_t *new = kmem_cache_zalloc(PGT_CACHE(hugepte_shift[psize]), |
106 | GFP_KERNEL|__GFP_REPEAT); | |
f10a04c0 DG |
107 | |
108 | if (! new) | |
109 | return -ENOMEM; | |
110 | ||
111 | spin_lock(&mm->page_table_lock); | |
112 | if (!hugepd_none(*hpdp)) | |
a0668cdc | 113 | kmem_cache_free(PGT_CACHE(hugepte_shift[psize]), new); |
f10a04c0 DG |
114 | else |
115 | hpdp->pd = (unsigned long)new | HUGEPD_OK; | |
116 | spin_unlock(&mm->page_table_lock); | |
117 | return 0; | |
118 | } | |
119 | ||
0b26425c DG |
120 | |
121 | static pud_t *hpud_offset(pgd_t *pgd, unsigned long addr, struct hstate *hstate) | |
122 | { | |
123 | if (huge_page_shift(hstate) < PUD_SHIFT) | |
124 | return pud_offset(pgd, addr); | |
125 | else | |
126 | return (pud_t *) pgd; | |
127 | } | |
128 | static pud_t *hpud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long addr, | |
129 | struct hstate *hstate) | |
4ec161cf | 130 | { |
0b26425c DG |
131 | if (huge_page_shift(hstate) < PUD_SHIFT) |
132 | return pud_alloc(mm, pgd, addr); | |
133 | else | |
134 | return (pud_t *) pgd; | |
135 | } | |
136 | static pmd_t *hpmd_offset(pud_t *pud, unsigned long addr, struct hstate *hstate) | |
137 | { | |
138 | if (huge_page_shift(hstate) < PMD_SHIFT) | |
4ec161cf JT |
139 | return pmd_offset(pud, addr); |
140 | else | |
141 | return (pmd_t *) pud; | |
142 | } | |
0b26425c DG |
143 | static pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr, |
144 | struct hstate *hstate) | |
4ec161cf | 145 | { |
0b26425c | 146 | if (huge_page_shift(hstate) < PMD_SHIFT) |
4ec161cf JT |
147 | return pmd_alloc(mm, pud, addr); |
148 | else | |
149 | return (pmd_t *) pud; | |
150 | } | |
4ec161cf | 151 | |
658013e9 JT |
152 | /* Build list of addresses of gigantic pages. This function is used in early |
153 | * boot before the buddy or bootmem allocator is setup. | |
154 | */ | |
155 | void add_gpage(unsigned long addr, unsigned long page_size, | |
156 | unsigned long number_of_pages) | |
157 | { | |
158 | if (!addr) | |
159 | return; | |
160 | while (number_of_pages > 0) { | |
161 | gpage_freearray[nr_gpages] = addr; | |
162 | nr_gpages++; | |
163 | number_of_pages--; | |
164 | addr += page_size; | |
165 | } | |
166 | } | |
167 | ||
ec4b2c0c | 168 | /* Moves the gigantic page addresses from the temporary list to the |
0d9ea754 JT |
169 | * huge_boot_pages list. |
170 | */ | |
171 | int alloc_bootmem_huge_page(struct hstate *hstate) | |
ec4b2c0c JT |
172 | { |
173 | struct huge_bootmem_page *m; | |
174 | if (nr_gpages == 0) | |
175 | return 0; | |
176 | m = phys_to_virt(gpage_freearray[--nr_gpages]); | |
177 | gpage_freearray[nr_gpages] = 0; | |
178 | list_add(&m->list, &huge_boot_pages); | |
0d9ea754 | 179 | m->hstate = hstate; |
ec4b2c0c JT |
180 | return 1; |
181 | } | |
182 | ||
183 | ||
e28f7faf DG |
184 | /* Modelled after find_linux_pte() */ |
185 | pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) | |
1da177e4 | 186 | { |
e28f7faf DG |
187 | pgd_t *pg; |
188 | pud_t *pu; | |
4ec161cf | 189 | pmd_t *pm; |
1da177e4 | 190 | |
0d9ea754 JT |
191 | unsigned int psize; |
192 | unsigned int shift; | |
193 | unsigned long sz; | |
194 | struct hstate *hstate; | |
195 | psize = get_slice_psize(mm, addr); | |
196 | shift = mmu_psize_to_shift(psize); | |
197 | sz = ((1UL) << shift); | |
198 | hstate = size_to_hstate(sz); | |
1da177e4 | 199 | |
0d9ea754 | 200 | addr &= hstate->mask; |
e28f7faf DG |
201 | |
202 | pg = pgd_offset(mm, addr); | |
203 | if (!pgd_none(*pg)) { | |
0b26425c | 204 | pu = hpud_offset(pg, addr, hstate); |
e28f7faf | 205 | if (!pud_none(*pu)) { |
0d9ea754 | 206 | pm = hpmd_offset(pu, addr, hstate); |
f10a04c0 | 207 | if (!pmd_none(*pm)) |
0d9ea754 JT |
208 | return hugepte_offset((hugepd_t *)pm, addr, |
209 | hstate); | |
e28f7faf DG |
210 | } |
211 | } | |
1da177e4 | 212 | |
e28f7faf | 213 | return NULL; |
1da177e4 LT |
214 | } |
215 | ||
a5516438 AK |
216 | pte_t *huge_pte_alloc(struct mm_struct *mm, |
217 | unsigned long addr, unsigned long sz) | |
1da177e4 | 218 | { |
e28f7faf DG |
219 | pgd_t *pg; |
220 | pud_t *pu; | |
4ec161cf | 221 | pmd_t *pm; |
f10a04c0 | 222 | hugepd_t *hpdp = NULL; |
0d9ea754 JT |
223 | struct hstate *hstate; |
224 | unsigned int psize; | |
225 | hstate = size_to_hstate(sz); | |
1da177e4 | 226 | |
0d9ea754 JT |
227 | psize = get_slice_psize(mm, addr); |
228 | BUG_ON(!mmu_huge_psizes[psize]); | |
1da177e4 | 229 | |
0d9ea754 | 230 | addr &= hstate->mask; |
1da177e4 | 231 | |
e28f7faf | 232 | pg = pgd_offset(mm, addr); |
0b26425c | 233 | pu = hpud_alloc(mm, pg, addr, hstate); |
1da177e4 | 234 | |
e28f7faf | 235 | if (pu) { |
0d9ea754 | 236 | pm = hpmd_alloc(mm, pu, addr, hstate); |
f10a04c0 DG |
237 | if (pm) |
238 | hpdp = (hugepd_t *)pm; | |
f10a04c0 DG |
239 | } |
240 | ||
241 | if (! hpdp) | |
242 | return NULL; | |
243 | ||
0d9ea754 | 244 | if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, psize)) |
f10a04c0 DG |
245 | return NULL; |
246 | ||
0d9ea754 | 247 | return hugepte_offset(hpdp, addr, hstate); |
f10a04c0 DG |
248 | } |
249 | ||
39dde65c CK |
250 | int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep) |
251 | { | |
252 | return 0; | |
253 | } | |
254 | ||
0d9ea754 JT |
255 | static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp, |
256 | unsigned int psize) | |
f10a04c0 DG |
257 | { |
258 | pte_t *hugepte = hugepd_page(*hpdp); | |
259 | ||
260 | hpdp->pd = 0; | |
261 | tlb->need_flush = 1; | |
a0668cdc | 262 | pgtable_free_tlb(tlb, hugepte, hugepte_shift[psize]); |
f10a04c0 DG |
263 | } |
264 | ||
f10a04c0 DG |
265 | static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud, |
266 | unsigned long addr, unsigned long end, | |
0d9ea754 JT |
267 | unsigned long floor, unsigned long ceiling, |
268 | unsigned int psize) | |
f10a04c0 DG |
269 | { |
270 | pmd_t *pmd; | |
271 | unsigned long next; | |
272 | unsigned long start; | |
273 | ||
274 | start = addr; | |
275 | pmd = pmd_offset(pud, addr); | |
276 | do { | |
277 | next = pmd_addr_end(addr, end); | |
278 | if (pmd_none(*pmd)) | |
279 | continue; | |
0d9ea754 | 280 | free_hugepte_range(tlb, (hugepd_t *)pmd, psize); |
f10a04c0 DG |
281 | } while (pmd++, addr = next, addr != end); |
282 | ||
283 | start &= PUD_MASK; | |
284 | if (start < floor) | |
285 | return; | |
286 | if (ceiling) { | |
287 | ceiling &= PUD_MASK; | |
288 | if (!ceiling) | |
289 | return; | |
1da177e4 | 290 | } |
f10a04c0 DG |
291 | if (end - 1 > ceiling - 1) |
292 | return; | |
1da177e4 | 293 | |
f10a04c0 DG |
294 | pmd = pmd_offset(pud, start); |
295 | pud_clear(pud); | |
9e1b32ca | 296 | pmd_free_tlb(tlb, pmd, start); |
f10a04c0 | 297 | } |
f10a04c0 DG |
298 | |
299 | static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd, | |
300 | unsigned long addr, unsigned long end, | |
301 | unsigned long floor, unsigned long ceiling) | |
302 | { | |
303 | pud_t *pud; | |
304 | unsigned long next; | |
305 | unsigned long start; | |
0d9ea754 JT |
306 | unsigned int shift; |
307 | unsigned int psize = get_slice_psize(tlb->mm, addr); | |
308 | shift = mmu_psize_to_shift(psize); | |
f10a04c0 DG |
309 | |
310 | start = addr; | |
311 | pud = pud_offset(pgd, addr); | |
312 | do { | |
313 | next = pud_addr_end(addr, end); | |
0b26425c | 314 | if (shift < PMD_SHIFT) { |
4ec161cf JT |
315 | if (pud_none_or_clear_bad(pud)) |
316 | continue; | |
0d9ea754 JT |
317 | hugetlb_free_pmd_range(tlb, pud, addr, next, floor, |
318 | ceiling, psize); | |
4ec161cf JT |
319 | } else { |
320 | if (pud_none(*pud)) | |
321 | continue; | |
0d9ea754 | 322 | free_hugepte_range(tlb, (hugepd_t *)pud, psize); |
4ec161cf | 323 | } |
f10a04c0 DG |
324 | } while (pud++, addr = next, addr != end); |
325 | ||
326 | start &= PGDIR_MASK; | |
327 | if (start < floor) | |
328 | return; | |
329 | if (ceiling) { | |
330 | ceiling &= PGDIR_MASK; | |
331 | if (!ceiling) | |
332 | return; | |
333 | } | |
334 | if (end - 1 > ceiling - 1) | |
335 | return; | |
336 | ||
337 | pud = pud_offset(pgd, start); | |
338 | pgd_clear(pgd); | |
9e1b32ca | 339 | pud_free_tlb(tlb, pud, start); |
f10a04c0 DG |
340 | } |
341 | ||
342 | /* | |
343 | * This function frees user-level page tables of a process. | |
344 | * | |
345 | * Must be called with pagetable lock held. | |
346 | */ | |
42b77728 | 347 | void hugetlb_free_pgd_range(struct mmu_gather *tlb, |
f10a04c0 DG |
348 | unsigned long addr, unsigned long end, |
349 | unsigned long floor, unsigned long ceiling) | |
350 | { | |
351 | pgd_t *pgd; | |
352 | unsigned long next; | |
353 | unsigned long start; | |
354 | ||
355 | /* | |
356 | * Comments below take from the normal free_pgd_range(). They | |
357 | * apply here too. The tests against HUGEPD_MASK below are | |
358 | * essential, because we *don't* test for this at the bottom | |
359 | * level. Without them we'll attempt to free a hugepte table | |
360 | * when we unmap just part of it, even if there are other | |
361 | * active mappings using it. | |
362 | * | |
363 | * The next few lines have given us lots of grief... | |
364 | * | |
365 | * Why are we testing HUGEPD* at this top level? Because | |
366 | * often there will be no work to do at all, and we'd prefer | |
367 | * not to go all the way down to the bottom just to discover | |
368 | * that. | |
369 | * | |
370 | * Why all these "- 1"s? Because 0 represents both the bottom | |
371 | * of the address space and the top of it (using -1 for the | |
372 | * top wouldn't help much: the masks would do the wrong thing). | |
373 | * The rule is that addr 0 and floor 0 refer to the bottom of | |
374 | * the address space, but end 0 and ceiling 0 refer to the top | |
375 | * Comparisons need to use "end - 1" and "ceiling - 1" (though | |
376 | * that end 0 case should be mythical). | |
377 | * | |
378 | * Wherever addr is brought up or ceiling brought down, we | |
379 | * must be careful to reject "the opposite 0" before it | |
380 | * confuses the subsequent tests. But what about where end is | |
381 | * brought down by HUGEPD_SIZE below? no, end can't go down to | |
382 | * 0 there. | |
383 | * | |
384 | * Whereas we round start (addr) and ceiling down, by different | |
385 | * masks at different levels, in order to test whether a table | |
386 | * now has no other vmas using it, so can be freed, we don't | |
387 | * bother to round floor or end up - the tests don't need that. | |
388 | */ | |
0d9ea754 | 389 | unsigned int psize = get_slice_psize(tlb->mm, addr); |
f10a04c0 | 390 | |
0d9ea754 | 391 | addr &= HUGEPD_MASK(psize); |
f10a04c0 | 392 | if (addr < floor) { |
0d9ea754 | 393 | addr += HUGEPD_SIZE(psize); |
f10a04c0 DG |
394 | if (!addr) |
395 | return; | |
396 | } | |
397 | if (ceiling) { | |
0d9ea754 | 398 | ceiling &= HUGEPD_MASK(psize); |
f10a04c0 DG |
399 | if (!ceiling) |
400 | return; | |
401 | } | |
402 | if (end - 1 > ceiling - 1) | |
0d9ea754 | 403 | end -= HUGEPD_SIZE(psize); |
f10a04c0 DG |
404 | if (addr > end - 1) |
405 | return; | |
406 | ||
407 | start = addr; | |
42b77728 | 408 | pgd = pgd_offset(tlb->mm, addr); |
f10a04c0 | 409 | do { |
0d9ea754 JT |
410 | psize = get_slice_psize(tlb->mm, addr); |
411 | BUG_ON(!mmu_huge_psizes[psize]); | |
f10a04c0 | 412 | next = pgd_addr_end(addr, end); |
0b26425c DG |
413 | if (mmu_psize_to_shift(psize) < PUD_SHIFT) { |
414 | if (pgd_none_or_clear_bad(pgd)) | |
415 | continue; | |
416 | hugetlb_free_pud_range(tlb, pgd, addr, next, floor, ceiling); | |
417 | } else { | |
418 | if (pgd_none(*pgd)) | |
419 | continue; | |
420 | free_hugepte_range(tlb, (hugepd_t *)pgd, psize); | |
421 | } | |
f10a04c0 | 422 | } while (pgd++, addr = next, addr != end); |
1da177e4 LT |
423 | } |
424 | ||
e28f7faf DG |
425 | void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, |
426 | pte_t *ptep, pte_t pte) | |
427 | { | |
e28f7faf | 428 | if (pte_present(*ptep)) { |
3c726f8d | 429 | /* We open-code pte_clear because we need to pass the right |
a741e679 BH |
430 | * argument to hpte_need_flush (huge / !huge). Might not be |
431 | * necessary anymore if we make hpte_need_flush() get the | |
432 | * page size from the slices | |
3c726f8d | 433 | */ |
f71dc176 | 434 | pte_update(mm, addr, ptep, ~0UL, 1); |
e28f7faf | 435 | } |
3c726f8d | 436 | *ptep = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS); |
1da177e4 LT |
437 | } |
438 | ||
e28f7faf DG |
439 | pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, |
440 | pte_t *ptep) | |
1da177e4 | 441 | { |
a741e679 | 442 | unsigned long old = pte_update(mm, addr, ptep, ~0UL, 1); |
e28f7faf | 443 | return __pte(old); |
1da177e4 LT |
444 | } |
445 | ||
1da177e4 LT |
446 | struct page * |
447 | follow_huge_addr(struct mm_struct *mm, unsigned long address, int write) | |
448 | { | |
449 | pte_t *ptep; | |
450 | struct page *page; | |
0d9ea754 | 451 | unsigned int mmu_psize = get_slice_psize(mm, address); |
1da177e4 | 452 | |
0d9ea754 JT |
453 | /* Verify it is a huge page else bail. */ |
454 | if (!mmu_huge_psizes[mmu_psize]) | |
1da177e4 LT |
455 | return ERR_PTR(-EINVAL); |
456 | ||
457 | ptep = huge_pte_offset(mm, address); | |
458 | page = pte_page(*ptep); | |
0d9ea754 JT |
459 | if (page) { |
460 | unsigned int shift = mmu_psize_to_shift(mmu_psize); | |
461 | unsigned long sz = ((1UL) << shift); | |
462 | page += (address % sz) / PAGE_SIZE; | |
463 | } | |
1da177e4 LT |
464 | |
465 | return page; | |
466 | } | |
467 | ||
468 | int pmd_huge(pmd_t pmd) | |
469 | { | |
470 | return 0; | |
471 | } | |
472 | ||
ceb86879 AK |
473 | int pud_huge(pud_t pud) |
474 | { | |
475 | return 0; | |
476 | } | |
477 | ||
1da177e4 LT |
478 | struct page * |
479 | follow_huge_pmd(struct mm_struct *mm, unsigned long address, | |
480 | pmd_t *pmd, int write) | |
481 | { | |
482 | BUG(); | |
483 | return NULL; | |
484 | } | |
485 | ||
1da177e4 LT |
486 | |
487 | unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, | |
488 | unsigned long len, unsigned long pgoff, | |
489 | unsigned long flags) | |
490 | { | |
0d9ea754 JT |
491 | struct hstate *hstate = hstate_file(file); |
492 | int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate)); | |
48f797de BK |
493 | |
494 | if (!mmu_huge_psizes[mmu_psize]) | |
495 | return -EINVAL; | |
0d9ea754 | 496 | return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1, 0); |
1da177e4 LT |
497 | } |
498 | ||
3340289d MG |
499 | unsigned long vma_mmu_pagesize(struct vm_area_struct *vma) |
500 | { | |
501 | unsigned int psize = get_slice_psize(vma->vm_mm, vma->vm_start); | |
502 | ||
503 | return 1UL << mmu_psize_to_shift(psize); | |
504 | } | |
505 | ||
cbf52afd DG |
506 | /* |
507 | * Called by asm hashtable.S for doing lazy icache flush | |
508 | */ | |
509 | static unsigned int hash_huge_page_do_lazy_icache(unsigned long rflags, | |
0d9ea754 | 510 | pte_t pte, int trap, unsigned long sz) |
cbf52afd DG |
511 | { |
512 | struct page *page; | |
513 | int i; | |
514 | ||
515 | if (!pfn_valid(pte_pfn(pte))) | |
516 | return rflags; | |
517 | ||
518 | page = pte_page(pte); | |
519 | ||
520 | /* page is dirty */ | |
521 | if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) { | |
522 | if (trap == 0x400) { | |
0d9ea754 | 523 | for (i = 0; i < (sz / PAGE_SIZE); i++) |
cbf52afd DG |
524 | __flush_dcache_icache(page_address(page+i)); |
525 | set_bit(PG_arch_1, &page->flags); | |
526 | } else { | |
527 | rflags |= HPTE_R_N; | |
528 | } | |
529 | } | |
530 | return rflags; | |
531 | } | |
532 | ||
1da177e4 | 533 | int hash_huge_page(struct mm_struct *mm, unsigned long access, |
cbf52afd DG |
534 | unsigned long ea, unsigned long vsid, int local, |
535 | unsigned long trap) | |
1da177e4 LT |
536 | { |
537 | pte_t *ptep; | |
3c726f8d | 538 | unsigned long old_pte, new_pte; |
0d9ea754 | 539 | unsigned long va, rflags, pa, sz; |
1da177e4 LT |
540 | long slot; |
541 | int err = 1; | |
1189be65 | 542 | int ssize = user_segment_size(ea); |
0d9ea754 JT |
543 | unsigned int mmu_psize; |
544 | int shift; | |
545 | mmu_psize = get_slice_psize(mm, ea); | |
1da177e4 | 546 | |
0d9ea754 JT |
547 | if (!mmu_huge_psizes[mmu_psize]) |
548 | goto out; | |
1da177e4 LT |
549 | ptep = huge_pte_offset(mm, ea); |
550 | ||
551 | /* Search the Linux page table for a match with va */ | |
1189be65 | 552 | va = hpt_va(ea, vsid, ssize); |
1da177e4 LT |
553 | |
554 | /* | |
555 | * If no pte found or not present, send the problem up to | |
556 | * do_page_fault | |
557 | */ | |
558 | if (unlikely(!ptep || pte_none(*ptep))) | |
559 | goto out; | |
560 | ||
1da177e4 LT |
561 | /* |
562 | * Check the user's access rights to the page. If access should be | |
563 | * prevented then send the problem up to do_page_fault. | |
564 | */ | |
565 | if (unlikely(access & ~pte_val(*ptep))) | |
566 | goto out; | |
567 | /* | |
568 | * At this point, we have a pte (old_pte) which can be used to build | |
569 | * or update an HPTE. There are 2 cases: | |
570 | * | |
571 | * 1. There is a valid (present) pte with no associated HPTE (this is | |
572 | * the most common case) | |
573 | * 2. There is a valid (present) pte with an associated HPTE. The | |
574 | * current values of the pp bits in the HPTE prevent access | |
575 | * because we are doing software DIRTY bit management and the | |
576 | * page is currently not DIRTY. | |
577 | */ | |
578 | ||
579 | ||
3c726f8d BH |
580 | do { |
581 | old_pte = pte_val(*ptep); | |
582 | if (old_pte & _PAGE_BUSY) | |
583 | goto out; | |
41743a4e | 584 | new_pte = old_pte | _PAGE_BUSY | _PAGE_ACCESSED; |
3c726f8d BH |
585 | } while(old_pte != __cmpxchg_u64((unsigned long *)ptep, |
586 | old_pte, new_pte)); | |
587 | ||
588 | rflags = 0x2 | (!(new_pte & _PAGE_RW)); | |
1da177e4 | 589 | /* _PAGE_EXEC -> HW_NO_EXEC since it's inverted */ |
3c726f8d | 590 | rflags |= ((new_pte & _PAGE_EXEC) ? 0 : HPTE_R_N); |
0d9ea754 JT |
591 | shift = mmu_psize_to_shift(mmu_psize); |
592 | sz = ((1UL) << shift); | |
cbf52afd DG |
593 | if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) |
594 | /* No CPU has hugepages but lacks no execute, so we | |
595 | * don't need to worry about that case */ | |
596 | rflags = hash_huge_page_do_lazy_icache(rflags, __pte(old_pte), | |
0d9ea754 | 597 | trap, sz); |
1da177e4 LT |
598 | |
599 | /* Check if pte already has an hpte (case 2) */ | |
3c726f8d | 600 | if (unlikely(old_pte & _PAGE_HASHPTE)) { |
1da177e4 LT |
601 | /* There MIGHT be an HPTE for this pte */ |
602 | unsigned long hash, slot; | |
603 | ||
0d9ea754 | 604 | hash = hpt_hash(va, shift, ssize); |
3c726f8d | 605 | if (old_pte & _PAGE_F_SECOND) |
1da177e4 LT |
606 | hash = ~hash; |
607 | slot = (hash & htab_hash_mask) * HPTES_PER_GROUP; | |
3c726f8d | 608 | slot += (old_pte & _PAGE_F_GIX) >> 12; |
1da177e4 | 609 | |
0d9ea754 | 610 | if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_psize, |
1189be65 | 611 | ssize, local) == -1) |
3c726f8d | 612 | old_pte &= ~_PAGE_HPTEFLAGS; |
1da177e4 LT |
613 | } |
614 | ||
3c726f8d | 615 | if (likely(!(old_pte & _PAGE_HASHPTE))) { |
0d9ea754 | 616 | unsigned long hash = hpt_hash(va, shift, ssize); |
1da177e4 LT |
617 | unsigned long hpte_group; |
618 | ||
3c726f8d | 619 | pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT; |
1da177e4 LT |
620 | |
621 | repeat: | |
622 | hpte_group = ((hash & htab_hash_mask) * | |
623 | HPTES_PER_GROUP) & ~0x7UL; | |
624 | ||
3c726f8d | 625 | /* clear HPTE slot informations in new PTE */ |
41743a4e BH |
626 | #ifdef CONFIG_PPC_64K_PAGES |
627 | new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | _PAGE_HPTE_SUB0; | |
628 | #else | |
3c726f8d | 629 | new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | _PAGE_HASHPTE; |
41743a4e | 630 | #endif |
1da177e4 | 631 | /* Add in WIMG bits */ |
87e9ab13 DK |
632 | rflags |= (new_pte & (_PAGE_WRITETHRU | _PAGE_NO_CACHE | |
633 | _PAGE_COHERENT | _PAGE_GUARDED)); | |
1da177e4 | 634 | |
3c726f8d BH |
635 | /* Insert into the hash table, primary slot */ |
636 | slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags, 0, | |
0d9ea754 | 637 | mmu_psize, ssize); |
1da177e4 LT |
638 | |
639 | /* Primary is full, try the secondary */ | |
640 | if (unlikely(slot == -1)) { | |
1da177e4 LT |
641 | hpte_group = ((~hash & htab_hash_mask) * |
642 | HPTES_PER_GROUP) & ~0x7UL; | |
3c726f8d | 643 | slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags, |
67b10813 | 644 | HPTE_V_SECONDARY, |
0d9ea754 | 645 | mmu_psize, ssize); |
1da177e4 LT |
646 | if (slot == -1) { |
647 | if (mftb() & 0x1) | |
67b10813 BH |
648 | hpte_group = ((hash & htab_hash_mask) * |
649 | HPTES_PER_GROUP)&~0x7UL; | |
1da177e4 LT |
650 | |
651 | ppc_md.hpte_remove(hpte_group); | |
652 | goto repeat; | |
653 | } | |
654 | } | |
655 | ||
656 | if (unlikely(slot == -2)) | |
657 | panic("hash_huge_page: pte_insert failed\n"); | |
658 | ||
d649bd7b | 659 | new_pte |= (slot << 12) & (_PAGE_F_SECOND | _PAGE_F_GIX); |
1da177e4 LT |
660 | } |
661 | ||
3c726f8d | 662 | /* |
01edcd89 | 663 | * No need to use ldarx/stdcx here |
3c726f8d BH |
664 | */ |
665 | *ptep = __pte(new_pte & ~_PAGE_BUSY); | |
666 | ||
1da177e4 LT |
667 | err = 0; |
668 | ||
669 | out: | |
1da177e4 LT |
670 | return err; |
671 | } | |
f10a04c0 | 672 | |
4ea8fb9c | 673 | static void __init set_huge_psize(int psize) |
4ec161cf JT |
674 | { |
675 | /* Check that it is a page size supported by the hardware and | |
676 | * that it fits within pagetable limits. */ | |
91224346 JT |
677 | if (mmu_psize_defs[psize].shift && |
678 | mmu_psize_defs[psize].shift < SID_SHIFT_1T && | |
4ec161cf | 679 | (mmu_psize_defs[psize].shift > MIN_HUGEPTE_SHIFT || |
91224346 JT |
680 | mmu_psize_defs[psize].shift == PAGE_SHIFT_64K || |
681 | mmu_psize_defs[psize].shift == PAGE_SHIFT_16G)) { | |
0d9ea754 JT |
682 | /* Return if huge page size has already been setup or is the |
683 | * same as the base page size. */ | |
684 | if (mmu_huge_psizes[psize] || | |
685 | mmu_psize_defs[psize].shift == PAGE_SHIFT) | |
91224346 | 686 | return; |
0d9ea754 | 687 | hugetlb_add_hstate(mmu_psize_defs[psize].shift - PAGE_SHIFT); |
91224346 | 688 | |
0d9ea754 | 689 | switch (mmu_psize_defs[psize].shift) { |
91224346 JT |
690 | case PAGE_SHIFT_64K: |
691 | /* We only allow 64k hpages with 4k base page, | |
692 | * which was checked above, and always put them | |
693 | * at the PMD */ | |
0d9ea754 | 694 | hugepte_shift[psize] = PMD_SHIFT; |
91224346 JT |
695 | break; |
696 | case PAGE_SHIFT_16M: | |
697 | /* 16M pages can be at two different levels | |
698 | * of pagestables based on base page size */ | |
699 | if (PAGE_SHIFT == PAGE_SHIFT_64K) | |
0d9ea754 | 700 | hugepte_shift[psize] = PMD_SHIFT; |
91224346 | 701 | else /* 4k base page */ |
0d9ea754 | 702 | hugepte_shift[psize] = PUD_SHIFT; |
91224346 JT |
703 | break; |
704 | case PAGE_SHIFT_16G: | |
705 | /* 16G pages are always at PGD level */ | |
0d9ea754 | 706 | hugepte_shift[psize] = PGDIR_SHIFT; |
91224346 JT |
707 | break; |
708 | } | |
0d9ea754 | 709 | hugepte_shift[psize] -= mmu_psize_defs[psize].shift; |
4ec161cf | 710 | } else |
0d9ea754 | 711 | hugepte_shift[psize] = 0; |
4ec161cf JT |
712 | } |
713 | ||
714 | static int __init hugepage_setup_sz(char *str) | |
715 | { | |
716 | unsigned long long size; | |
0d9ea754 | 717 | int mmu_psize; |
4ec161cf JT |
718 | int shift; |
719 | ||
720 | size = memparse(str, &str); | |
721 | ||
722 | shift = __ffs(size); | |
0d9ea754 JT |
723 | mmu_psize = shift_to_mmu_psize(shift); |
724 | if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift) | |
4ec161cf JT |
725 | set_huge_psize(mmu_psize); |
726 | else | |
727 | printk(KERN_WARNING "Invalid huge page size specified(%llu)\n", size); | |
728 | ||
729 | return 1; | |
730 | } | |
731 | __setup("hugepagesz=", hugepage_setup_sz); | |
732 | ||
f10a04c0 DG |
733 | static int __init hugetlbpage_init(void) |
734 | { | |
0d9ea754 JT |
735 | unsigned int psize; |
736 | ||
f10a04c0 DG |
737 | if (!cpu_has_feature(CPU_FTR_16M_PAGE)) |
738 | return -ENODEV; | |
00df438e | 739 | |
a0668cdc DG |
740 | /* Add supported huge page sizes. Need to change |
741 | * HUGE_MAX_HSTATE if the number of supported huge page sizes | |
742 | * changes. | |
0d9ea754 JT |
743 | */ |
744 | set_huge_psize(MMU_PAGE_16M); | |
0d9ea754 JT |
745 | set_huge_psize(MMU_PAGE_16G); |
746 | ||
00df438e BH |
747 | /* Temporarily disable support for 64K huge pages when 64K SPU local |
748 | * store support is enabled as the current implementation conflicts. | |
749 | */ | |
750 | #ifndef CONFIG_SPU_FS_64K_LS | |
751 | set_huge_psize(MMU_PAGE_64K); | |
752 | #endif | |
753 | ||
0d9ea754 JT |
754 | for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) { |
755 | if (mmu_huge_psizes[psize]) { | |
a0668cdc DG |
756 | pgtable_cache_add(hugepte_shift[psize], NULL); |
757 | if (!PGT_CACHE(hugepte_shift[psize])) | |
758 | panic("hugetlbpage_init(): could not create " | |
759 | "pgtable cache for %d bit pagesize\n", | |
760 | mmu_psize_to_shift(psize)); | |
0d9ea754 JT |
761 | } |
762 | } | |
f10a04c0 DG |
763 | |
764 | return 0; | |
765 | } | |
766 | ||
767 | module_init(hugetlbpage_init); |