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 | |
46 | #define PTRS_PER_HUGEPTE(psize) (1 << hugepte_shift[psize]) | |
47 | #define HUGEPTE_TABLE_SIZE(psize) (sizeof(pte_t) << hugepte_shift[psize]) | |
48 | ||
49 | #define HUGEPD_SHIFT(psize) (mmu_psize_to_shift(psize) \ | |
50 | + hugepte_shift[psize]) | |
51 | #define HUGEPD_SIZE(psize) (1UL << HUGEPD_SHIFT(psize)) | |
52 | #define HUGEPD_MASK(psize) (~(HUGEPD_SIZE(psize)-1)) | |
f10a04c0 | 53 | |
0d9ea754 JT |
54 | /* Subtract one from array size because we don't need a cache for 4K since |
55 | * is not a huge page size */ | |
7d4320f3 | 56 | #define HUGE_PGTABLE_INDEX(psize) (HUGEPTE_CACHE_NUM + psize - 1) |
0d9ea754 | 57 | #define HUGEPTE_CACHE_NAME(psize) (huge_pgtable_cache_name[psize]) |
f10a04c0 | 58 | |
0d9ea754 JT |
59 | static const char *huge_pgtable_cache_name[MMU_PAGE_COUNT] = { |
60 | "unused_4K", "hugepte_cache_64K", "unused_64K_AP", | |
61 | "hugepte_cache_1M", "hugepte_cache_16M", "hugepte_cache_16G" | |
62 | }; | |
f10a04c0 DG |
63 | |
64 | /* Flag to mark huge PD pointers. This means pmd_bad() and pud_bad() | |
65 | * will choke on pointers to hugepte tables, which is handy for | |
66 | * catching screwups early. */ | |
67 | #define HUGEPD_OK 0x1 | |
68 | ||
69 | typedef struct { unsigned long pd; } hugepd_t; | |
70 | ||
71 | #define hugepd_none(hpd) ((hpd).pd == 0) | |
72 | ||
0d9ea754 JT |
73 | static inline int shift_to_mmu_psize(unsigned int shift) |
74 | { | |
75 | switch (shift) { | |
76 | #ifndef CONFIG_PPC_64K_PAGES | |
77 | case PAGE_SHIFT_64K: | |
78 | return MMU_PAGE_64K; | |
79 | #endif | |
80 | case PAGE_SHIFT_16M: | |
81 | return MMU_PAGE_16M; | |
82 | case PAGE_SHIFT_16G: | |
83 | return MMU_PAGE_16G; | |
84 | } | |
85 | return -1; | |
86 | } | |
87 | ||
88 | static inline unsigned int mmu_psize_to_shift(unsigned int mmu_psize) | |
89 | { | |
90 | if (mmu_psize_defs[mmu_psize].shift) | |
91 | return mmu_psize_defs[mmu_psize].shift; | |
92 | BUG(); | |
93 | } | |
94 | ||
f10a04c0 DG |
95 | static inline pte_t *hugepd_page(hugepd_t hpd) |
96 | { | |
97 | BUG_ON(!(hpd.pd & HUGEPD_OK)); | |
98 | return (pte_t *)(hpd.pd & ~HUGEPD_OK); | |
99 | } | |
100 | ||
0d9ea754 JT |
101 | static inline pte_t *hugepte_offset(hugepd_t *hpdp, unsigned long addr, |
102 | struct hstate *hstate) | |
f10a04c0 | 103 | { |
0d9ea754 JT |
104 | unsigned int shift = huge_page_shift(hstate); |
105 | int psize = shift_to_mmu_psize(shift); | |
106 | unsigned long idx = ((addr >> shift) & (PTRS_PER_HUGEPTE(psize)-1)); | |
f10a04c0 DG |
107 | pte_t *dir = hugepd_page(*hpdp); |
108 | ||
109 | return dir + idx; | |
110 | } | |
111 | ||
112 | static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp, | |
0d9ea754 | 113 | unsigned long address, unsigned int psize) |
f10a04c0 | 114 | { |
7d4320f3 | 115 | pte_t *new = kmem_cache_zalloc(pgtable_cache[HUGE_PGTABLE_INDEX(psize)], |
f10a04c0 DG |
116 | GFP_KERNEL|__GFP_REPEAT); |
117 | ||
118 | if (! new) | |
119 | return -ENOMEM; | |
120 | ||
121 | spin_lock(&mm->page_table_lock); | |
122 | if (!hugepd_none(*hpdp)) | |
7d4320f3 | 123 | kmem_cache_free(pgtable_cache[HUGE_PGTABLE_INDEX(psize)], new); |
f10a04c0 DG |
124 | else |
125 | hpdp->pd = (unsigned long)new | HUGEPD_OK; | |
126 | spin_unlock(&mm->page_table_lock); | |
127 | return 0; | |
128 | } | |
129 | ||
0b26425c DG |
130 | |
131 | static pud_t *hpud_offset(pgd_t *pgd, unsigned long addr, struct hstate *hstate) | |
132 | { | |
133 | if (huge_page_shift(hstate) < PUD_SHIFT) | |
134 | return pud_offset(pgd, addr); | |
135 | else | |
136 | return (pud_t *) pgd; | |
137 | } | |
138 | static pud_t *hpud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long addr, | |
139 | struct hstate *hstate) | |
4ec161cf | 140 | { |
0b26425c DG |
141 | if (huge_page_shift(hstate) < PUD_SHIFT) |
142 | return pud_alloc(mm, pgd, addr); | |
143 | else | |
144 | return (pud_t *) pgd; | |
145 | } | |
146 | static pmd_t *hpmd_offset(pud_t *pud, unsigned long addr, struct hstate *hstate) | |
147 | { | |
148 | if (huge_page_shift(hstate) < PMD_SHIFT) | |
4ec161cf JT |
149 | return pmd_offset(pud, addr); |
150 | else | |
151 | return (pmd_t *) pud; | |
152 | } | |
0b26425c DG |
153 | static pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr, |
154 | struct hstate *hstate) | |
4ec161cf | 155 | { |
0b26425c | 156 | if (huge_page_shift(hstate) < PMD_SHIFT) |
4ec161cf JT |
157 | return pmd_alloc(mm, pud, addr); |
158 | else | |
159 | return (pmd_t *) pud; | |
160 | } | |
4ec161cf | 161 | |
658013e9 JT |
162 | /* Build list of addresses of gigantic pages. This function is used in early |
163 | * boot before the buddy or bootmem allocator is setup. | |
164 | */ | |
165 | void add_gpage(unsigned long addr, unsigned long page_size, | |
166 | unsigned long number_of_pages) | |
167 | { | |
168 | if (!addr) | |
169 | return; | |
170 | while (number_of_pages > 0) { | |
171 | gpage_freearray[nr_gpages] = addr; | |
172 | nr_gpages++; | |
173 | number_of_pages--; | |
174 | addr += page_size; | |
175 | } | |
176 | } | |
177 | ||
ec4b2c0c | 178 | /* Moves the gigantic page addresses from the temporary list to the |
0d9ea754 JT |
179 | * huge_boot_pages list. |
180 | */ | |
181 | int alloc_bootmem_huge_page(struct hstate *hstate) | |
ec4b2c0c JT |
182 | { |
183 | struct huge_bootmem_page *m; | |
184 | if (nr_gpages == 0) | |
185 | return 0; | |
186 | m = phys_to_virt(gpage_freearray[--nr_gpages]); | |
187 | gpage_freearray[nr_gpages] = 0; | |
188 | list_add(&m->list, &huge_boot_pages); | |
0d9ea754 | 189 | m->hstate = hstate; |
ec4b2c0c JT |
190 | return 1; |
191 | } | |
192 | ||
193 | ||
e28f7faf DG |
194 | /* Modelled after find_linux_pte() */ |
195 | pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) | |
1da177e4 | 196 | { |
e28f7faf DG |
197 | pgd_t *pg; |
198 | pud_t *pu; | |
4ec161cf | 199 | pmd_t *pm; |
1da177e4 | 200 | |
0d9ea754 JT |
201 | unsigned int psize; |
202 | unsigned int shift; | |
203 | unsigned long sz; | |
204 | struct hstate *hstate; | |
205 | psize = get_slice_psize(mm, addr); | |
206 | shift = mmu_psize_to_shift(psize); | |
207 | sz = ((1UL) << shift); | |
208 | hstate = size_to_hstate(sz); | |
1da177e4 | 209 | |
0d9ea754 | 210 | addr &= hstate->mask; |
e28f7faf DG |
211 | |
212 | pg = pgd_offset(mm, addr); | |
213 | if (!pgd_none(*pg)) { | |
0b26425c | 214 | pu = hpud_offset(pg, addr, hstate); |
e28f7faf | 215 | if (!pud_none(*pu)) { |
0d9ea754 | 216 | pm = hpmd_offset(pu, addr, hstate); |
f10a04c0 | 217 | if (!pmd_none(*pm)) |
0d9ea754 JT |
218 | return hugepte_offset((hugepd_t *)pm, addr, |
219 | hstate); | |
e28f7faf DG |
220 | } |
221 | } | |
1da177e4 | 222 | |
e28f7faf | 223 | return NULL; |
1da177e4 LT |
224 | } |
225 | ||
a5516438 AK |
226 | pte_t *huge_pte_alloc(struct mm_struct *mm, |
227 | unsigned long addr, unsigned long sz) | |
1da177e4 | 228 | { |
e28f7faf DG |
229 | pgd_t *pg; |
230 | pud_t *pu; | |
4ec161cf | 231 | pmd_t *pm; |
f10a04c0 | 232 | hugepd_t *hpdp = NULL; |
0d9ea754 JT |
233 | struct hstate *hstate; |
234 | unsigned int psize; | |
235 | hstate = size_to_hstate(sz); | |
1da177e4 | 236 | |
0d9ea754 JT |
237 | psize = get_slice_psize(mm, addr); |
238 | BUG_ON(!mmu_huge_psizes[psize]); | |
1da177e4 | 239 | |
0d9ea754 | 240 | addr &= hstate->mask; |
1da177e4 | 241 | |
e28f7faf | 242 | pg = pgd_offset(mm, addr); |
0b26425c | 243 | pu = hpud_alloc(mm, pg, addr, hstate); |
1da177e4 | 244 | |
e28f7faf | 245 | if (pu) { |
0d9ea754 | 246 | pm = hpmd_alloc(mm, pu, addr, hstate); |
f10a04c0 DG |
247 | if (pm) |
248 | hpdp = (hugepd_t *)pm; | |
f10a04c0 DG |
249 | } |
250 | ||
251 | if (! hpdp) | |
252 | return NULL; | |
253 | ||
0d9ea754 | 254 | if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, psize)) |
f10a04c0 DG |
255 | return NULL; |
256 | ||
0d9ea754 | 257 | return hugepte_offset(hpdp, addr, hstate); |
f10a04c0 DG |
258 | } |
259 | ||
39dde65c KC |
260 | int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep) |
261 | { | |
262 | return 0; | |
263 | } | |
264 | ||
0d9ea754 JT |
265 | static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp, |
266 | unsigned int psize) | |
f10a04c0 DG |
267 | { |
268 | pte_t *hugepte = hugepd_page(*hpdp); | |
269 | ||
270 | hpdp->pd = 0; | |
271 | tlb->need_flush = 1; | |
0d9ea754 JT |
272 | pgtable_free_tlb(tlb, pgtable_free_cache(hugepte, |
273 | HUGEPTE_CACHE_NUM+psize-1, | |
c9169f87 | 274 | PGF_CACHENUM_MASK)); |
f10a04c0 DG |
275 | } |
276 | ||
f10a04c0 DG |
277 | static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud, |
278 | unsigned long addr, unsigned long end, | |
0d9ea754 JT |
279 | unsigned long floor, unsigned long ceiling, |
280 | unsigned int psize) | |
f10a04c0 DG |
281 | { |
282 | pmd_t *pmd; | |
283 | unsigned long next; | |
284 | unsigned long start; | |
285 | ||
286 | start = addr; | |
287 | pmd = pmd_offset(pud, addr); | |
288 | do { | |
289 | next = pmd_addr_end(addr, end); | |
290 | if (pmd_none(*pmd)) | |
291 | continue; | |
0d9ea754 | 292 | free_hugepte_range(tlb, (hugepd_t *)pmd, psize); |
f10a04c0 DG |
293 | } while (pmd++, addr = next, addr != end); |
294 | ||
295 | start &= PUD_MASK; | |
296 | if (start < floor) | |
297 | return; | |
298 | if (ceiling) { | |
299 | ceiling &= PUD_MASK; | |
300 | if (!ceiling) | |
301 | return; | |
1da177e4 | 302 | } |
f10a04c0 DG |
303 | if (end - 1 > ceiling - 1) |
304 | return; | |
1da177e4 | 305 | |
f10a04c0 DG |
306 | pmd = pmd_offset(pud, start); |
307 | pud_clear(pud); | |
9e1b32ca | 308 | pmd_free_tlb(tlb, pmd, start); |
f10a04c0 | 309 | } |
f10a04c0 DG |
310 | |
311 | static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd, | |
312 | unsigned long addr, unsigned long end, | |
313 | unsigned long floor, unsigned long ceiling) | |
314 | { | |
315 | pud_t *pud; | |
316 | unsigned long next; | |
317 | unsigned long start; | |
0d9ea754 JT |
318 | unsigned int shift; |
319 | unsigned int psize = get_slice_psize(tlb->mm, addr); | |
320 | shift = mmu_psize_to_shift(psize); | |
f10a04c0 DG |
321 | |
322 | start = addr; | |
323 | pud = pud_offset(pgd, addr); | |
324 | do { | |
325 | next = pud_addr_end(addr, end); | |
0b26425c | 326 | if (shift < PMD_SHIFT) { |
4ec161cf JT |
327 | if (pud_none_or_clear_bad(pud)) |
328 | continue; | |
0d9ea754 JT |
329 | hugetlb_free_pmd_range(tlb, pud, addr, next, floor, |
330 | ceiling, psize); | |
4ec161cf JT |
331 | } else { |
332 | if (pud_none(*pud)) | |
333 | continue; | |
0d9ea754 | 334 | free_hugepte_range(tlb, (hugepd_t *)pud, psize); |
4ec161cf | 335 | } |
f10a04c0 DG |
336 | } while (pud++, addr = next, addr != end); |
337 | ||
338 | start &= PGDIR_MASK; | |
339 | if (start < floor) | |
340 | return; | |
341 | if (ceiling) { | |
342 | ceiling &= PGDIR_MASK; | |
343 | if (!ceiling) | |
344 | return; | |
345 | } | |
346 | if (end - 1 > ceiling - 1) | |
347 | return; | |
348 | ||
349 | pud = pud_offset(pgd, start); | |
350 | pgd_clear(pgd); | |
9e1b32ca | 351 | pud_free_tlb(tlb, pud, start); |
f10a04c0 DG |
352 | } |
353 | ||
354 | /* | |
355 | * This function frees user-level page tables of a process. | |
356 | * | |
357 | * Must be called with pagetable lock held. | |
358 | */ | |
42b77728 | 359 | void hugetlb_free_pgd_range(struct mmu_gather *tlb, |
f10a04c0 DG |
360 | unsigned long addr, unsigned long end, |
361 | unsigned long floor, unsigned long ceiling) | |
362 | { | |
363 | pgd_t *pgd; | |
364 | unsigned long next; | |
365 | unsigned long start; | |
366 | ||
367 | /* | |
368 | * Comments below take from the normal free_pgd_range(). They | |
369 | * apply here too. The tests against HUGEPD_MASK below are | |
370 | * essential, because we *don't* test for this at the bottom | |
371 | * level. Without them we'll attempt to free a hugepte table | |
372 | * when we unmap just part of it, even if there are other | |
373 | * active mappings using it. | |
374 | * | |
375 | * The next few lines have given us lots of grief... | |
376 | * | |
377 | * Why are we testing HUGEPD* at this top level? Because | |
378 | * often there will be no work to do at all, and we'd prefer | |
379 | * not to go all the way down to the bottom just to discover | |
380 | * that. | |
381 | * | |
382 | * Why all these "- 1"s? Because 0 represents both the bottom | |
383 | * of the address space and the top of it (using -1 for the | |
384 | * top wouldn't help much: the masks would do the wrong thing). | |
385 | * The rule is that addr 0 and floor 0 refer to the bottom of | |
386 | * the address space, but end 0 and ceiling 0 refer to the top | |
387 | * Comparisons need to use "end - 1" and "ceiling - 1" (though | |
388 | * that end 0 case should be mythical). | |
389 | * | |
390 | * Wherever addr is brought up or ceiling brought down, we | |
391 | * must be careful to reject "the opposite 0" before it | |
392 | * confuses the subsequent tests. But what about where end is | |
393 | * brought down by HUGEPD_SIZE below? no, end can't go down to | |
394 | * 0 there. | |
395 | * | |
396 | * Whereas we round start (addr) and ceiling down, by different | |
397 | * masks at different levels, in order to test whether a table | |
398 | * now has no other vmas using it, so can be freed, we don't | |
399 | * bother to round floor or end up - the tests don't need that. | |
400 | */ | |
0d9ea754 | 401 | unsigned int psize = get_slice_psize(tlb->mm, addr); |
f10a04c0 | 402 | |
0d9ea754 | 403 | addr &= HUGEPD_MASK(psize); |
f10a04c0 | 404 | if (addr < floor) { |
0d9ea754 | 405 | addr += HUGEPD_SIZE(psize); |
f10a04c0 DG |
406 | if (!addr) |
407 | return; | |
408 | } | |
409 | if (ceiling) { | |
0d9ea754 | 410 | ceiling &= HUGEPD_MASK(psize); |
f10a04c0 DG |
411 | if (!ceiling) |
412 | return; | |
413 | } | |
414 | if (end - 1 > ceiling - 1) | |
0d9ea754 | 415 | end -= HUGEPD_SIZE(psize); |
f10a04c0 DG |
416 | if (addr > end - 1) |
417 | return; | |
418 | ||
419 | start = addr; | |
42b77728 | 420 | pgd = pgd_offset(tlb->mm, addr); |
f10a04c0 | 421 | do { |
0d9ea754 JT |
422 | psize = get_slice_psize(tlb->mm, addr); |
423 | BUG_ON(!mmu_huge_psizes[psize]); | |
f10a04c0 | 424 | next = pgd_addr_end(addr, end); |
0b26425c DG |
425 | if (mmu_psize_to_shift(psize) < PUD_SHIFT) { |
426 | if (pgd_none_or_clear_bad(pgd)) | |
427 | continue; | |
428 | hugetlb_free_pud_range(tlb, pgd, addr, next, floor, ceiling); | |
429 | } else { | |
430 | if (pgd_none(*pgd)) | |
431 | continue; | |
432 | free_hugepte_range(tlb, (hugepd_t *)pgd, psize); | |
433 | } | |
f10a04c0 | 434 | } while (pgd++, addr = next, addr != end); |
1da177e4 LT |
435 | } |
436 | ||
e28f7faf DG |
437 | void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, |
438 | pte_t *ptep, pte_t pte) | |
439 | { | |
e28f7faf | 440 | if (pte_present(*ptep)) { |
3c726f8d | 441 | /* We open-code pte_clear because we need to pass the right |
a741e679 BH |
442 | * argument to hpte_need_flush (huge / !huge). Might not be |
443 | * necessary anymore if we make hpte_need_flush() get the | |
444 | * page size from the slices | |
3c726f8d | 445 | */ |
0d9ea754 JT |
446 | unsigned int psize = get_slice_psize(mm, addr); |
447 | unsigned int shift = mmu_psize_to_shift(psize); | |
448 | unsigned long sz = ((1UL) << shift); | |
449 | struct hstate *hstate = size_to_hstate(sz); | |
450 | pte_update(mm, addr & hstate->mask, ptep, ~0UL, 1); | |
e28f7faf | 451 | } |
3c726f8d | 452 | *ptep = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS); |
1da177e4 LT |
453 | } |
454 | ||
e28f7faf DG |
455 | pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, |
456 | pte_t *ptep) | |
1da177e4 | 457 | { |
a741e679 | 458 | unsigned long old = pte_update(mm, addr, ptep, ~0UL, 1); |
e28f7faf | 459 | return __pte(old); |
1da177e4 LT |
460 | } |
461 | ||
1da177e4 LT |
462 | struct page * |
463 | follow_huge_addr(struct mm_struct *mm, unsigned long address, int write) | |
464 | { | |
465 | pte_t *ptep; | |
466 | struct page *page; | |
0d9ea754 | 467 | unsigned int mmu_psize = get_slice_psize(mm, address); |
1da177e4 | 468 | |
0d9ea754 JT |
469 | /* Verify it is a huge page else bail. */ |
470 | if (!mmu_huge_psizes[mmu_psize]) | |
1da177e4 LT |
471 | return ERR_PTR(-EINVAL); |
472 | ||
473 | ptep = huge_pte_offset(mm, address); | |
474 | page = pte_page(*ptep); | |
0d9ea754 JT |
475 | if (page) { |
476 | unsigned int shift = mmu_psize_to_shift(mmu_psize); | |
477 | unsigned long sz = ((1UL) << shift); | |
478 | page += (address % sz) / PAGE_SIZE; | |
479 | } | |
1da177e4 LT |
480 | |
481 | return page; | |
482 | } | |
483 | ||
484 | int pmd_huge(pmd_t pmd) | |
485 | { | |
486 | return 0; | |
487 | } | |
488 | ||
ceb86879 AK |
489 | int pud_huge(pud_t pud) |
490 | { | |
491 | return 0; | |
492 | } | |
493 | ||
1da177e4 LT |
494 | struct page * |
495 | follow_huge_pmd(struct mm_struct *mm, unsigned long address, | |
496 | pmd_t *pmd, int write) | |
497 | { | |
498 | BUG(); | |
499 | return NULL; | |
500 | } | |
501 | ||
1da177e4 LT |
502 | |
503 | unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, | |
504 | unsigned long len, unsigned long pgoff, | |
505 | unsigned long flags) | |
506 | { | |
0d9ea754 JT |
507 | struct hstate *hstate = hstate_file(file); |
508 | int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate)); | |
48f797de BK |
509 | |
510 | if (!mmu_huge_psizes[mmu_psize]) | |
511 | return -EINVAL; | |
0d9ea754 | 512 | return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1, 0); |
1da177e4 LT |
513 | } |
514 | ||
3340289d MG |
515 | unsigned long vma_mmu_pagesize(struct vm_area_struct *vma) |
516 | { | |
517 | unsigned int psize = get_slice_psize(vma->vm_mm, vma->vm_start); | |
518 | ||
519 | return 1UL << mmu_psize_to_shift(psize); | |
520 | } | |
521 | ||
cbf52afd DG |
522 | /* |
523 | * Called by asm hashtable.S for doing lazy icache flush | |
524 | */ | |
525 | static unsigned int hash_huge_page_do_lazy_icache(unsigned long rflags, | |
0d9ea754 | 526 | pte_t pte, int trap, unsigned long sz) |
cbf52afd DG |
527 | { |
528 | struct page *page; | |
529 | int i; | |
530 | ||
531 | if (!pfn_valid(pte_pfn(pte))) | |
532 | return rflags; | |
533 | ||
534 | page = pte_page(pte); | |
535 | ||
536 | /* page is dirty */ | |
537 | if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) { | |
538 | if (trap == 0x400) { | |
0d9ea754 | 539 | for (i = 0; i < (sz / PAGE_SIZE); i++) |
cbf52afd DG |
540 | __flush_dcache_icache(page_address(page+i)); |
541 | set_bit(PG_arch_1, &page->flags); | |
542 | } else { | |
543 | rflags |= HPTE_R_N; | |
544 | } | |
545 | } | |
546 | return rflags; | |
547 | } | |
548 | ||
1da177e4 | 549 | int hash_huge_page(struct mm_struct *mm, unsigned long access, |
cbf52afd DG |
550 | unsigned long ea, unsigned long vsid, int local, |
551 | unsigned long trap) | |
1da177e4 LT |
552 | { |
553 | pte_t *ptep; | |
3c726f8d | 554 | unsigned long old_pte, new_pte; |
0d9ea754 | 555 | unsigned long va, rflags, pa, sz; |
1da177e4 LT |
556 | long slot; |
557 | int err = 1; | |
1189be65 | 558 | int ssize = user_segment_size(ea); |
0d9ea754 JT |
559 | unsigned int mmu_psize; |
560 | int shift; | |
561 | mmu_psize = get_slice_psize(mm, ea); | |
1da177e4 | 562 | |
0d9ea754 JT |
563 | if (!mmu_huge_psizes[mmu_psize]) |
564 | goto out; | |
1da177e4 LT |
565 | ptep = huge_pte_offset(mm, ea); |
566 | ||
567 | /* Search the Linux page table for a match with va */ | |
1189be65 | 568 | va = hpt_va(ea, vsid, ssize); |
1da177e4 LT |
569 | |
570 | /* | |
571 | * If no pte found or not present, send the problem up to | |
572 | * do_page_fault | |
573 | */ | |
574 | if (unlikely(!ptep || pte_none(*ptep))) | |
575 | goto out; | |
576 | ||
1da177e4 LT |
577 | /* |
578 | * Check the user's access rights to the page. If access should be | |
579 | * prevented then send the problem up to do_page_fault. | |
580 | */ | |
581 | if (unlikely(access & ~pte_val(*ptep))) | |
582 | goto out; | |
583 | /* | |
584 | * At this point, we have a pte (old_pte) which can be used to build | |
585 | * or update an HPTE. There are 2 cases: | |
586 | * | |
587 | * 1. There is a valid (present) pte with no associated HPTE (this is | |
588 | * the most common case) | |
589 | * 2. There is a valid (present) pte with an associated HPTE. The | |
590 | * current values of the pp bits in the HPTE prevent access | |
591 | * because we are doing software DIRTY bit management and the | |
592 | * page is currently not DIRTY. | |
593 | */ | |
594 | ||
595 | ||
3c726f8d BH |
596 | do { |
597 | old_pte = pte_val(*ptep); | |
598 | if (old_pte & _PAGE_BUSY) | |
599 | goto out; | |
41743a4e | 600 | new_pte = old_pte | _PAGE_BUSY | _PAGE_ACCESSED; |
3c726f8d BH |
601 | } while(old_pte != __cmpxchg_u64((unsigned long *)ptep, |
602 | old_pte, new_pte)); | |
603 | ||
604 | rflags = 0x2 | (!(new_pte & _PAGE_RW)); | |
1da177e4 | 605 | /* _PAGE_EXEC -> HW_NO_EXEC since it's inverted */ |
3c726f8d | 606 | rflags |= ((new_pte & _PAGE_EXEC) ? 0 : HPTE_R_N); |
0d9ea754 JT |
607 | shift = mmu_psize_to_shift(mmu_psize); |
608 | sz = ((1UL) << shift); | |
cbf52afd DG |
609 | if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) |
610 | /* No CPU has hugepages but lacks no execute, so we | |
611 | * don't need to worry about that case */ | |
612 | rflags = hash_huge_page_do_lazy_icache(rflags, __pte(old_pte), | |
0d9ea754 | 613 | trap, sz); |
1da177e4 LT |
614 | |
615 | /* Check if pte already has an hpte (case 2) */ | |
3c726f8d | 616 | if (unlikely(old_pte & _PAGE_HASHPTE)) { |
1da177e4 LT |
617 | /* There MIGHT be an HPTE for this pte */ |
618 | unsigned long hash, slot; | |
619 | ||
0d9ea754 | 620 | hash = hpt_hash(va, shift, ssize); |
3c726f8d | 621 | if (old_pte & _PAGE_F_SECOND) |
1da177e4 LT |
622 | hash = ~hash; |
623 | slot = (hash & htab_hash_mask) * HPTES_PER_GROUP; | |
3c726f8d | 624 | slot += (old_pte & _PAGE_F_GIX) >> 12; |
1da177e4 | 625 | |
0d9ea754 | 626 | if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_psize, |
1189be65 | 627 | ssize, local) == -1) |
3c726f8d | 628 | old_pte &= ~_PAGE_HPTEFLAGS; |
1da177e4 LT |
629 | } |
630 | ||
3c726f8d | 631 | if (likely(!(old_pte & _PAGE_HASHPTE))) { |
0d9ea754 | 632 | unsigned long hash = hpt_hash(va, shift, ssize); |
1da177e4 LT |
633 | unsigned long hpte_group; |
634 | ||
3c726f8d | 635 | pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT; |
1da177e4 LT |
636 | |
637 | repeat: | |
638 | hpte_group = ((hash & htab_hash_mask) * | |
639 | HPTES_PER_GROUP) & ~0x7UL; | |
640 | ||
3c726f8d | 641 | /* clear HPTE slot informations in new PTE */ |
41743a4e BH |
642 | #ifdef CONFIG_PPC_64K_PAGES |
643 | new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | _PAGE_HPTE_SUB0; | |
644 | #else | |
3c726f8d | 645 | new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | _PAGE_HASHPTE; |
41743a4e | 646 | #endif |
1da177e4 | 647 | /* Add in WIMG bits */ |
87e9ab13 DK |
648 | rflags |= (new_pte & (_PAGE_WRITETHRU | _PAGE_NO_CACHE | |
649 | _PAGE_COHERENT | _PAGE_GUARDED)); | |
1da177e4 | 650 | |
3c726f8d BH |
651 | /* Insert into the hash table, primary slot */ |
652 | slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags, 0, | |
0d9ea754 | 653 | mmu_psize, ssize); |
1da177e4 LT |
654 | |
655 | /* Primary is full, try the secondary */ | |
656 | if (unlikely(slot == -1)) { | |
1da177e4 LT |
657 | hpte_group = ((~hash & htab_hash_mask) * |
658 | HPTES_PER_GROUP) & ~0x7UL; | |
3c726f8d | 659 | slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags, |
67b10813 | 660 | HPTE_V_SECONDARY, |
0d9ea754 | 661 | mmu_psize, ssize); |
1da177e4 LT |
662 | if (slot == -1) { |
663 | if (mftb() & 0x1) | |
67b10813 BH |
664 | hpte_group = ((hash & htab_hash_mask) * |
665 | HPTES_PER_GROUP)&~0x7UL; | |
1da177e4 LT |
666 | |
667 | ppc_md.hpte_remove(hpte_group); | |
668 | goto repeat; | |
669 | } | |
670 | } | |
671 | ||
672 | if (unlikely(slot == -2)) | |
673 | panic("hash_huge_page: pte_insert failed\n"); | |
674 | ||
d649bd7b | 675 | new_pte |= (slot << 12) & (_PAGE_F_SECOND | _PAGE_F_GIX); |
1da177e4 LT |
676 | } |
677 | ||
3c726f8d | 678 | /* |
01edcd89 | 679 | * No need to use ldarx/stdcx here |
3c726f8d BH |
680 | */ |
681 | *ptep = __pte(new_pte & ~_PAGE_BUSY); | |
682 | ||
1da177e4 LT |
683 | err = 0; |
684 | ||
685 | out: | |
1da177e4 LT |
686 | return err; |
687 | } | |
f10a04c0 | 688 | |
4ea8fb9c | 689 | static void __init set_huge_psize(int psize) |
4ec161cf JT |
690 | { |
691 | /* Check that it is a page size supported by the hardware and | |
692 | * that it fits within pagetable limits. */ | |
91224346 JT |
693 | if (mmu_psize_defs[psize].shift && |
694 | mmu_psize_defs[psize].shift < SID_SHIFT_1T && | |
4ec161cf | 695 | (mmu_psize_defs[psize].shift > MIN_HUGEPTE_SHIFT || |
91224346 JT |
696 | mmu_psize_defs[psize].shift == PAGE_SHIFT_64K || |
697 | mmu_psize_defs[psize].shift == PAGE_SHIFT_16G)) { | |
0d9ea754 JT |
698 | /* Return if huge page size has already been setup or is the |
699 | * same as the base page size. */ | |
700 | if (mmu_huge_psizes[psize] || | |
701 | mmu_psize_defs[psize].shift == PAGE_SHIFT) | |
91224346 | 702 | return; |
0d9ea754 | 703 | hugetlb_add_hstate(mmu_psize_defs[psize].shift - PAGE_SHIFT); |
91224346 | 704 | |
0d9ea754 | 705 | switch (mmu_psize_defs[psize].shift) { |
91224346 JT |
706 | case PAGE_SHIFT_64K: |
707 | /* We only allow 64k hpages with 4k base page, | |
708 | * which was checked above, and always put them | |
709 | * at the PMD */ | |
0d9ea754 | 710 | hugepte_shift[psize] = PMD_SHIFT; |
91224346 JT |
711 | break; |
712 | case PAGE_SHIFT_16M: | |
713 | /* 16M pages can be at two different levels | |
714 | * of pagestables based on base page size */ | |
715 | if (PAGE_SHIFT == PAGE_SHIFT_64K) | |
0d9ea754 | 716 | hugepte_shift[psize] = PMD_SHIFT; |
91224346 | 717 | else /* 4k base page */ |
0d9ea754 | 718 | hugepte_shift[psize] = PUD_SHIFT; |
91224346 JT |
719 | break; |
720 | case PAGE_SHIFT_16G: | |
721 | /* 16G pages are always at PGD level */ | |
0d9ea754 | 722 | hugepte_shift[psize] = PGDIR_SHIFT; |
91224346 JT |
723 | break; |
724 | } | |
0d9ea754 | 725 | hugepte_shift[psize] -= mmu_psize_defs[psize].shift; |
4ec161cf | 726 | } else |
0d9ea754 | 727 | hugepte_shift[psize] = 0; |
4ec161cf JT |
728 | } |
729 | ||
730 | static int __init hugepage_setup_sz(char *str) | |
731 | { | |
732 | unsigned long long size; | |
0d9ea754 | 733 | int mmu_psize; |
4ec161cf JT |
734 | int shift; |
735 | ||
736 | size = memparse(str, &str); | |
737 | ||
738 | shift = __ffs(size); | |
0d9ea754 JT |
739 | mmu_psize = shift_to_mmu_psize(shift); |
740 | if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift) | |
4ec161cf JT |
741 | set_huge_psize(mmu_psize); |
742 | else | |
743 | printk(KERN_WARNING "Invalid huge page size specified(%llu)\n", size); | |
744 | ||
745 | return 1; | |
746 | } | |
747 | __setup("hugepagesz=", hugepage_setup_sz); | |
748 | ||
f10a04c0 DG |
749 | static int __init hugetlbpage_init(void) |
750 | { | |
0d9ea754 JT |
751 | unsigned int psize; |
752 | ||
f10a04c0 DG |
753 | if (!cpu_has_feature(CPU_FTR_16M_PAGE)) |
754 | return -ENODEV; | |
00df438e | 755 | |
0d9ea754 JT |
756 | /* Add supported huge page sizes. Need to change HUGE_MAX_HSTATE |
757 | * and adjust PTE_NONCACHE_NUM if the number of supported huge page | |
758 | * sizes changes. | |
759 | */ | |
760 | set_huge_psize(MMU_PAGE_16M); | |
0d9ea754 JT |
761 | set_huge_psize(MMU_PAGE_16G); |
762 | ||
00df438e BH |
763 | /* Temporarily disable support for 64K huge pages when 64K SPU local |
764 | * store support is enabled as the current implementation conflicts. | |
765 | */ | |
766 | #ifndef CONFIG_SPU_FS_64K_LS | |
767 | set_huge_psize(MMU_PAGE_64K); | |
768 | #endif | |
769 | ||
0d9ea754 JT |
770 | for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) { |
771 | if (mmu_huge_psizes[psize]) { | |
7d4320f3 JT |
772 | pgtable_cache[HUGE_PGTABLE_INDEX(psize)] = |
773 | kmem_cache_create( | |
774 | HUGEPTE_CACHE_NAME(psize), | |
775 | HUGEPTE_TABLE_SIZE(psize), | |
776 | HUGEPTE_TABLE_SIZE(psize), | |
777 | 0, | |
778 | NULL); | |
779 | if (!pgtable_cache[HUGE_PGTABLE_INDEX(psize)]) | |
0d9ea754 JT |
780 | panic("hugetlbpage_init(): could not create %s"\ |
781 | "\n", HUGEPTE_CACHE_NAME(psize)); | |
782 | } | |
783 | } | |
f10a04c0 DG |
784 | |
785 | return 0; | |
786 | } | |
787 | ||
788 | module_init(hugetlbpage_init); |