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1/*
2 * PPC Huge TLB Page Support for Kernel.
3 *
4 * Copyright (C) 2003 David Gibson, IBM Corporation.
5 * Copyright (C) 2011 Becky Bruce, Freescale Semiconductor
6 *
7 * Based on the IA-32 version:
8 * Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com>
9 */
10
11#include <linux/mm.h>
12#include <linux/io.h>
13#include <linux/slab.h>
14#include <linux/hugetlb.h>
15#include <linux/export.h>
16#include <linux/of_fdt.h>
17#include <linux/memblock.h>
18#include <linux/moduleparam.h>
19#include <linux/swap.h>
20#include <linux/swapops.h>
21#include <linux/kmemleak.h>
22#include <asm/pgalloc.h>
23#include <asm/tlb.h>
24#include <asm/setup.h>
25#include <asm/hugetlb.h>
26#include <asm/pte-walk.h>
27#include <asm/firmware.h>
28
29bool hugetlb_disabled = false;
30
31#define hugepd_none(hpd) (hpd_val(hpd) == 0)
32
33#define PTE_T_ORDER (__builtin_ffs(sizeof(pte_basic_t)) - \
34 __builtin_ffs(sizeof(void *)))
35
36pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr, unsigned long sz)
37{
38 /*
39 * Only called for hugetlbfs pages, hence can ignore THP and the
40 * irq disabled walk.
41 */
42 return __find_linux_pte(mm->pgd, addr, NULL, NULL);
43}
44
45static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
46 unsigned long address, unsigned int pdshift,
47 unsigned int pshift, spinlock_t *ptl)
48{
49 struct kmem_cache *cachep;
50 pte_t *new;
51 int i;
52 int num_hugepd;
53
54 if (pshift >= pdshift) {
55 cachep = PGT_CACHE(PTE_T_ORDER);
56 num_hugepd = 1 << (pshift - pdshift);
57 } else {
58 cachep = PGT_CACHE(pdshift - pshift);
59 num_hugepd = 1;
60 }
61
62 if (!cachep) {
63 WARN_ONCE(1, "No page table cache created for hugetlb tables");
64 return -ENOMEM;
65 }
66
67 new = kmem_cache_alloc(cachep, pgtable_gfp_flags(mm, GFP_KERNEL));
68
69 BUG_ON(pshift > HUGEPD_SHIFT_MASK);
70 BUG_ON((unsigned long)new & HUGEPD_SHIFT_MASK);
71
72 if (!new)
73 return -ENOMEM;
74
75 /*
76 * Make sure other cpus find the hugepd set only after a
77 * properly initialized page table is visible to them.
78 * For more details look for comment in __pte_alloc().
79 */
80 smp_wmb();
81
82 spin_lock(ptl);
83 /*
84 * We have multiple higher-level entries that point to the same
85 * actual pte location. Fill in each as we go and backtrack on error.
86 * We need all of these so the DTLB pgtable walk code can find the
87 * right higher-level entry without knowing if it's a hugepage or not.
88 */
89 for (i = 0; i < num_hugepd; i++, hpdp++) {
90 if (unlikely(!hugepd_none(*hpdp)))
91 break;
92 hugepd_populate(hpdp, new, pshift);
93 }
94 /* If we bailed from the for loop early, an error occurred, clean up */
95 if (i < num_hugepd) {
96 for (i = i - 1 ; i >= 0; i--, hpdp--)
97 *hpdp = __hugepd(0);
98 kmem_cache_free(cachep, new);
99 } else {
100 kmemleak_ignore(new);
101 }
102 spin_unlock(ptl);
103 return 0;
104}
105
106/*
107 * At this point we do the placement change only for BOOK3S 64. This would
108 * possibly work on other subarchs.
109 */
110pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
111 unsigned long addr, unsigned long sz)
112{
113 pgd_t *pg;
114 p4d_t *p4;
115 pud_t *pu;
116 pmd_t *pm;
117 hugepd_t *hpdp = NULL;
118 unsigned pshift = __ffs(sz);
119 unsigned pdshift = PGDIR_SHIFT;
120 spinlock_t *ptl;
121
122 addr &= ~(sz-1);
123 pg = pgd_offset(mm, addr);
124 p4 = p4d_offset(pg, addr);
125
126#ifdef CONFIG_PPC_BOOK3S_64
127 if (pshift == PGDIR_SHIFT)
128 /* 16GB huge page */
129 return (pte_t *) p4;
130 else if (pshift > PUD_SHIFT) {
131 /*
132 * We need to use hugepd table
133 */
134 ptl = &mm->page_table_lock;
135 hpdp = (hugepd_t *)p4;
136 } else {
137 pdshift = PUD_SHIFT;
138 pu = pud_alloc(mm, p4, addr);
139 if (!pu)
140 return NULL;
141 if (pshift == PUD_SHIFT)
142 return (pte_t *)pu;
143 else if (pshift > PMD_SHIFT) {
144 ptl = pud_lockptr(mm, pu);
145 hpdp = (hugepd_t *)pu;
146 } else {
147 pdshift = PMD_SHIFT;
148 pm = pmd_alloc(mm, pu, addr);
149 if (!pm)
150 return NULL;
151 if (pshift == PMD_SHIFT)
152 /* 16MB hugepage */
153 return (pte_t *)pm;
154 else {
155 ptl = pmd_lockptr(mm, pm);
156 hpdp = (hugepd_t *)pm;
157 }
158 }
159 }
160#else
161 if (pshift >= PGDIR_SHIFT) {
162 ptl = &mm->page_table_lock;
163 hpdp = (hugepd_t *)p4;
164 } else {
165 pdshift = PUD_SHIFT;
166 pu = pud_alloc(mm, p4, addr);
167 if (!pu)
168 return NULL;
169 if (pshift >= PUD_SHIFT) {
170 ptl = pud_lockptr(mm, pu);
171 hpdp = (hugepd_t *)pu;
172 } else {
173 pdshift = PMD_SHIFT;
174 pm = pmd_alloc(mm, pu, addr);
175 if (!pm)
176 return NULL;
177 ptl = pmd_lockptr(mm, pm);
178 hpdp = (hugepd_t *)pm;
179 }
180 }
181#endif
182 if (!hpdp)
183 return NULL;
184
185 if (IS_ENABLED(CONFIG_PPC_8xx) && pshift < PMD_SHIFT)
186 return pte_alloc_huge(mm, (pmd_t *)hpdp, addr);
187
188 BUG_ON(!hugepd_none(*hpdp) && !hugepd_ok(*hpdp));
189
190 if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr,
191 pdshift, pshift, ptl))
192 return NULL;
193
194 return hugepte_offset(*hpdp, addr, pdshift);
195}
196
197#ifdef CONFIG_PPC_BOOK3S_64
198/*
199 * Tracks gpages after the device tree is scanned and before the
200 * huge_boot_pages list is ready on pseries.
201 */
202#define MAX_NUMBER_GPAGES 1024
203__initdata static u64 gpage_freearray[MAX_NUMBER_GPAGES];
204__initdata static unsigned nr_gpages;
205
206/*
207 * Build list of addresses of gigantic pages. This function is used in early
208 * boot before the buddy allocator is setup.
209 */
210void __init pseries_add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages)
211{
212 if (!addr)
213 return;
214 while (number_of_pages > 0) {
215 gpage_freearray[nr_gpages] = addr;
216 nr_gpages++;
217 number_of_pages--;
218 addr += page_size;
219 }
220}
221
222static int __init pseries_alloc_bootmem_huge_page(struct hstate *hstate)
223{
224 struct huge_bootmem_page *m;
225 if (nr_gpages == 0)
226 return 0;
227 m = phys_to_virt(gpage_freearray[--nr_gpages]);
228 gpage_freearray[nr_gpages] = 0;
229 list_add(&m->list, &huge_boot_pages);
230 m->hstate = hstate;
231 return 1;
232}
233
234bool __init hugetlb_node_alloc_supported(void)
235{
236 return false;
237}
238#endif
239
240
241int __init alloc_bootmem_huge_page(struct hstate *h, int nid)
242{
243
244#ifdef CONFIG_PPC_BOOK3S_64
245 if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
246 return pseries_alloc_bootmem_huge_page(h);
247#endif
248 return __alloc_bootmem_huge_page(h, nid);
249}
250
251#ifndef CONFIG_PPC_BOOK3S_64
252#define HUGEPD_FREELIST_SIZE \
253 ((PAGE_SIZE - sizeof(struct hugepd_freelist)) / sizeof(pte_t))
254
255struct hugepd_freelist {
256 struct rcu_head rcu;
257 unsigned int index;
258 void *ptes[];
259};
260
261static DEFINE_PER_CPU(struct hugepd_freelist *, hugepd_freelist_cur);
262
263static void hugepd_free_rcu_callback(struct rcu_head *head)
264{
265 struct hugepd_freelist *batch =
266 container_of(head, struct hugepd_freelist, rcu);
267 unsigned int i;
268
269 for (i = 0; i < batch->index; i++)
270 kmem_cache_free(PGT_CACHE(PTE_T_ORDER), batch->ptes[i]);
271
272 free_page((unsigned long)batch);
273}
274
275static void hugepd_free(struct mmu_gather *tlb, void *hugepte)
276{
277 struct hugepd_freelist **batchp;
278
279 batchp = &get_cpu_var(hugepd_freelist_cur);
280
281 if (atomic_read(&tlb->mm->mm_users) < 2 ||
282 mm_is_thread_local(tlb->mm)) {
283 kmem_cache_free(PGT_CACHE(PTE_T_ORDER), hugepte);
284 put_cpu_var(hugepd_freelist_cur);
285 return;
286 }
287
288 if (*batchp == NULL) {
289 *batchp = (struct hugepd_freelist *)__get_free_page(GFP_ATOMIC);
290 (*batchp)->index = 0;
291 }
292
293 (*batchp)->ptes[(*batchp)->index++] = hugepte;
294 if ((*batchp)->index == HUGEPD_FREELIST_SIZE) {
295 call_rcu(&(*batchp)->rcu, hugepd_free_rcu_callback);
296 *batchp = NULL;
297 }
298 put_cpu_var(hugepd_freelist_cur);
299}
300#else
301static inline void hugepd_free(struct mmu_gather *tlb, void *hugepte) {}
302#endif
303
304/* Return true when the entry to be freed maps more than the area being freed */
305static bool range_is_outside_limits(unsigned long start, unsigned long end,
306 unsigned long floor, unsigned long ceiling,
307 unsigned long mask)
308{
309 if ((start & mask) < floor)
310 return true;
311 if (ceiling) {
312 ceiling &= mask;
313 if (!ceiling)
314 return true;
315 }
316 return end - 1 > ceiling - 1;
317}
318
319static void free_hugepd_range(struct mmu_gather *tlb, hugepd_t *hpdp, int pdshift,
320 unsigned long start, unsigned long end,
321 unsigned long floor, unsigned long ceiling)
322{
323 pte_t *hugepte = hugepd_page(*hpdp);
324 int i;
325
326 unsigned long pdmask = ~((1UL << pdshift) - 1);
327 unsigned int num_hugepd = 1;
328 unsigned int shift = hugepd_shift(*hpdp);
329
330 /* Note: On fsl the hpdp may be the first of several */
331 if (shift > pdshift)
332 num_hugepd = 1 << (shift - pdshift);
333
334 if (range_is_outside_limits(start, end, floor, ceiling, pdmask))
335 return;
336
337 for (i = 0; i < num_hugepd; i++, hpdp++)
338 *hpdp = __hugepd(0);
339
340 if (shift >= pdshift)
341 hugepd_free(tlb, hugepte);
342 else
343 pgtable_free_tlb(tlb, hugepte,
344 get_hugepd_cache_index(pdshift - shift));
345}
346
347static void hugetlb_free_pte_range(struct mmu_gather *tlb, pmd_t *pmd,
348 unsigned long addr, unsigned long end,
349 unsigned long floor, unsigned long ceiling)
350{
351 pgtable_t token = pmd_pgtable(*pmd);
352
353 if (range_is_outside_limits(addr, end, floor, ceiling, PMD_MASK))
354 return;
355
356 pmd_clear(pmd);
357 pte_free_tlb(tlb, token, addr);
358 mm_dec_nr_ptes(tlb->mm);
359}
360
361static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
362 unsigned long addr, unsigned long end,
363 unsigned long floor, unsigned long ceiling)
364{
365 pmd_t *pmd;
366 unsigned long next;
367 unsigned long start;
368
369 start = addr;
370 do {
371 unsigned long more;
372
373 pmd = pmd_offset(pud, addr);
374 next = pmd_addr_end(addr, end);
375 if (!is_hugepd(__hugepd(pmd_val(*pmd)))) {
376 if (pmd_none_or_clear_bad(pmd))
377 continue;
378
379 /*
380 * if it is not hugepd pointer, we should already find
381 * it cleared.
382 */
383 WARN_ON(!IS_ENABLED(CONFIG_PPC_8xx));
384
385 hugetlb_free_pte_range(tlb, pmd, addr, end, floor, ceiling);
386
387 continue;
388 }
389 /*
390 * Increment next by the size of the huge mapping since
391 * there may be more than one entry at this level for a
392 * single hugepage, but all of them point to
393 * the same kmem cache that holds the hugepte.
394 */
395 more = addr + (1UL << hugepd_shift(*(hugepd_t *)pmd));
396 if (more > next)
397 next = more;
398
399 free_hugepd_range(tlb, (hugepd_t *)pmd, PMD_SHIFT,
400 addr, next, floor, ceiling);
401 } while (addr = next, addr != end);
402
403 if (range_is_outside_limits(start, end, floor, ceiling, PUD_MASK))
404 return;
405
406 pmd = pmd_offset(pud, start & PUD_MASK);
407 pud_clear(pud);
408 pmd_free_tlb(tlb, pmd, start & PUD_MASK);
409 mm_dec_nr_pmds(tlb->mm);
410}
411
412static void hugetlb_free_pud_range(struct mmu_gather *tlb, p4d_t *p4d,
413 unsigned long addr, unsigned long end,
414 unsigned long floor, unsigned long ceiling)
415{
416 pud_t *pud;
417 unsigned long next;
418 unsigned long start;
419
420 start = addr;
421 do {
422 pud = pud_offset(p4d, addr);
423 next = pud_addr_end(addr, end);
424 if (!is_hugepd(__hugepd(pud_val(*pud)))) {
425 if (pud_none_or_clear_bad(pud))
426 continue;
427 hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
428 ceiling);
429 } else {
430 unsigned long more;
431 /*
432 * Increment next by the size of the huge mapping since
433 * there may be more than one entry at this level for a
434 * single hugepage, but all of them point to
435 * the same kmem cache that holds the hugepte.
436 */
437 more = addr + (1UL << hugepd_shift(*(hugepd_t *)pud));
438 if (more > next)
439 next = more;
440
441 free_hugepd_range(tlb, (hugepd_t *)pud, PUD_SHIFT,
442 addr, next, floor, ceiling);
443 }
444 } while (addr = next, addr != end);
445
446 if (range_is_outside_limits(start, end, floor, ceiling, PGDIR_MASK))
447 return;
448
449 pud = pud_offset(p4d, start & PGDIR_MASK);
450 p4d_clear(p4d);
451 pud_free_tlb(tlb, pud, start & PGDIR_MASK);
452 mm_dec_nr_puds(tlb->mm);
453}
454
455/*
456 * This function frees user-level page tables of a process.
457 */
458void hugetlb_free_pgd_range(struct mmu_gather *tlb,
459 unsigned long addr, unsigned long end,
460 unsigned long floor, unsigned long ceiling)
461{
462 pgd_t *pgd;
463 p4d_t *p4d;
464 unsigned long next;
465
466 /*
467 * Because there are a number of different possible pagetable
468 * layouts for hugepage ranges, we limit knowledge of how
469 * things should be laid out to the allocation path
470 * (huge_pte_alloc(), above). Everything else works out the
471 * structure as it goes from information in the hugepd
472 * pointers. That means that we can't here use the
473 * optimization used in the normal page free_pgd_range(), of
474 * checking whether we're actually covering a large enough
475 * range to have to do anything at the top level of the walk
476 * instead of at the bottom.
477 *
478 * To make sense of this, you should probably go read the big
479 * block comment at the top of the normal free_pgd_range(),
480 * too.
481 */
482
483 do {
484 next = pgd_addr_end(addr, end);
485 pgd = pgd_offset(tlb->mm, addr);
486 p4d = p4d_offset(pgd, addr);
487 if (!is_hugepd(__hugepd(pgd_val(*pgd)))) {
488 if (p4d_none_or_clear_bad(p4d))
489 continue;
490 hugetlb_free_pud_range(tlb, p4d, addr, next, floor, ceiling);
491 } else {
492 unsigned long more;
493 /*
494 * Increment next by the size of the huge mapping since
495 * there may be more than one entry at the pgd level
496 * for a single hugepage, but all of them point to the
497 * same kmem cache that holds the hugepte.
498 */
499 more = addr + (1UL << hugepd_shift(*(hugepd_t *)pgd));
500 if (more > next)
501 next = more;
502
503 free_hugepd_range(tlb, (hugepd_t *)p4d, PGDIR_SHIFT,
504 addr, next, floor, ceiling);
505 }
506 } while (addr = next, addr != end);
507}
508
509bool __init arch_hugetlb_valid_size(unsigned long size)
510{
511 int shift = __ffs(size);
512 int mmu_psize;
513
514 /* Check that it is a page size supported by the hardware and
515 * that it fits within pagetable and slice limits. */
516 if (size <= PAGE_SIZE || !is_power_of_2(size))
517 return false;
518
519 mmu_psize = check_and_get_huge_psize(shift);
520 if (mmu_psize < 0)
521 return false;
522
523 BUG_ON(mmu_psize_defs[mmu_psize].shift != shift);
524
525 return true;
526}
527
528static int __init add_huge_page_size(unsigned long long size)
529{
530 int shift = __ffs(size);
531
532 if (!arch_hugetlb_valid_size((unsigned long)size))
533 return -EINVAL;
534
535 hugetlb_add_hstate(shift - PAGE_SHIFT);
536 return 0;
537}
538
539static int __init hugetlbpage_init(void)
540{
541 bool configured = false;
542 int psize;
543
544 if (hugetlb_disabled) {
545 pr_info("HugeTLB support is disabled!\n");
546 return 0;
547 }
548
549 if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && !radix_enabled() &&
550 !mmu_has_feature(MMU_FTR_16M_PAGE))
551 return -ENODEV;
552
553 for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
554 unsigned shift;
555 unsigned pdshift;
556
557 if (!mmu_psize_defs[psize].shift)
558 continue;
559
560 shift = mmu_psize_to_shift(psize);
561
562#ifdef CONFIG_PPC_BOOK3S_64
563 if (shift > PGDIR_SHIFT)
564 continue;
565 else if (shift > PUD_SHIFT)
566 pdshift = PGDIR_SHIFT;
567 else if (shift > PMD_SHIFT)
568 pdshift = PUD_SHIFT;
569 else
570 pdshift = PMD_SHIFT;
571#else
572 if (shift < PUD_SHIFT)
573 pdshift = PMD_SHIFT;
574 else if (shift < PGDIR_SHIFT)
575 pdshift = PUD_SHIFT;
576 else
577 pdshift = PGDIR_SHIFT;
578#endif
579
580 if (add_huge_page_size(1ULL << shift) < 0)
581 continue;
582 /*
583 * if we have pdshift and shift value same, we don't
584 * use pgt cache for hugepd.
585 */
586 if (pdshift > shift) {
587 if (!IS_ENABLED(CONFIG_PPC_8xx))
588 pgtable_cache_add(pdshift - shift);
589 } else if (IS_ENABLED(CONFIG_PPC_E500) ||
590 IS_ENABLED(CONFIG_PPC_8xx)) {
591 pgtable_cache_add(PTE_T_ORDER);
592 }
593
594 configured = true;
595 }
596
597 if (!configured)
598 pr_info("Failed to initialize. Disabling HugeTLB");
599
600 return 0;
601}
602
603arch_initcall(hugetlbpage_init);
604
605void __init gigantic_hugetlb_cma_reserve(void)
606{
607 unsigned long order = 0;
608
609 if (radix_enabled())
610 order = PUD_SHIFT - PAGE_SHIFT;
611 else if (!firmware_has_feature(FW_FEATURE_LPAR) && mmu_psize_defs[MMU_PAGE_16G].shift)
612 /*
613 * For pseries we do use ibm,expected#pages for reserving 16G pages.
614 */
615 order = mmu_psize_to_shift(MMU_PAGE_16G) - PAGE_SHIFT;
616
617 if (order) {
618 VM_WARN_ON(order <= MAX_PAGE_ORDER);
619 hugetlb_cma_reserve(order);
620 }
621}
1/*
2 * PPC Huge TLB Page Support for Kernel.
3 *
4 * Copyright (C) 2003 David Gibson, IBM Corporation.
5 * Copyright (C) 2011 Becky Bruce, Freescale Semiconductor
6 *
7 * Based on the IA-32 version:
8 * Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com>
9 */
10
11#include <linux/mm.h>
12#include <linux/io.h>
13#include <linux/slab.h>
14#include <linux/hugetlb.h>
15#include <linux/export.h>
16#include <linux/of_fdt.h>
17#include <linux/memblock.h>
18#include <linux/bootmem.h>
19#include <linux/moduleparam.h>
20#include <asm/pgtable.h>
21#include <asm/pgalloc.h>
22#include <asm/tlb.h>
23#include <asm/setup.h>
24
25#define PAGE_SHIFT_64K 16
26#define PAGE_SHIFT_16M 24
27#define PAGE_SHIFT_16G 34
28
29unsigned int HPAGE_SHIFT;
30
31/*
32 * Tracks gpages after the device tree is scanned and before the
33 * huge_boot_pages list is ready. On non-Freescale implementations, this is
34 * just used to track 16G pages and so is a single array. FSL-based
35 * implementations may have more than one gpage size, so we need multiple
36 * arrays
37 */
38#ifdef CONFIG_PPC_FSL_BOOK3E
39#define MAX_NUMBER_GPAGES 128
40struct psize_gpages {
41 u64 gpage_list[MAX_NUMBER_GPAGES];
42 unsigned int nr_gpages;
43};
44static struct psize_gpages gpage_freearray[MMU_PAGE_COUNT];
45#else
46#define MAX_NUMBER_GPAGES 1024
47static u64 gpage_freearray[MAX_NUMBER_GPAGES];
48static unsigned nr_gpages;
49#endif
50
51static inline int shift_to_mmu_psize(unsigned int shift)
52{
53 int psize;
54
55 for (psize = 0; psize < MMU_PAGE_COUNT; ++psize)
56 if (mmu_psize_defs[psize].shift == shift)
57 return psize;
58 return -1;
59}
60
61static inline unsigned int mmu_psize_to_shift(unsigned int mmu_psize)
62{
63 if (mmu_psize_defs[mmu_psize].shift)
64 return mmu_psize_defs[mmu_psize].shift;
65 BUG();
66}
67
68#define hugepd_none(hpd) ((hpd).pd == 0)
69
70pte_t *find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea, unsigned *shift)
71{
72 pgd_t *pg;
73 pud_t *pu;
74 pmd_t *pm;
75 hugepd_t *hpdp = NULL;
76 unsigned pdshift = PGDIR_SHIFT;
77
78 if (shift)
79 *shift = 0;
80
81 pg = pgdir + pgd_index(ea);
82 if (is_hugepd(pg)) {
83 hpdp = (hugepd_t *)pg;
84 } else if (!pgd_none(*pg)) {
85 pdshift = PUD_SHIFT;
86 pu = pud_offset(pg, ea);
87 if (is_hugepd(pu))
88 hpdp = (hugepd_t *)pu;
89 else if (!pud_none(*pu)) {
90 pdshift = PMD_SHIFT;
91 pm = pmd_offset(pu, ea);
92 if (is_hugepd(pm))
93 hpdp = (hugepd_t *)pm;
94 else if (!pmd_none(*pm)) {
95 return pte_offset_kernel(pm, ea);
96 }
97 }
98 }
99
100 if (!hpdp)
101 return NULL;
102
103 if (shift)
104 *shift = hugepd_shift(*hpdp);
105 return hugepte_offset(hpdp, ea, pdshift);
106}
107EXPORT_SYMBOL_GPL(find_linux_pte_or_hugepte);
108
109pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
110{
111 return find_linux_pte_or_hugepte(mm->pgd, addr, NULL);
112}
113
114static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
115 unsigned long address, unsigned pdshift, unsigned pshift)
116{
117 struct kmem_cache *cachep;
118 pte_t *new;
119
120#ifdef CONFIG_PPC_FSL_BOOK3E
121 int i;
122 int num_hugepd = 1 << (pshift - pdshift);
123 cachep = hugepte_cache;
124#else
125 cachep = PGT_CACHE(pdshift - pshift);
126#endif
127
128 new = kmem_cache_zalloc(cachep, GFP_KERNEL|__GFP_REPEAT);
129
130 BUG_ON(pshift > HUGEPD_SHIFT_MASK);
131 BUG_ON((unsigned long)new & HUGEPD_SHIFT_MASK);
132
133 if (! new)
134 return -ENOMEM;
135
136 spin_lock(&mm->page_table_lock);
137#ifdef CONFIG_PPC_FSL_BOOK3E
138 /*
139 * We have multiple higher-level entries that point to the same
140 * actual pte location. Fill in each as we go and backtrack on error.
141 * We need all of these so the DTLB pgtable walk code can find the
142 * right higher-level entry without knowing if it's a hugepage or not.
143 */
144 for (i = 0; i < num_hugepd; i++, hpdp++) {
145 if (unlikely(!hugepd_none(*hpdp)))
146 break;
147 else
148 hpdp->pd = ((unsigned long)new & ~PD_HUGE) | pshift;
149 }
150 /* If we bailed from the for loop early, an error occurred, clean up */
151 if (i < num_hugepd) {
152 for (i = i - 1 ; i >= 0; i--, hpdp--)
153 hpdp->pd = 0;
154 kmem_cache_free(cachep, new);
155 }
156#else
157 if (!hugepd_none(*hpdp))
158 kmem_cache_free(cachep, new);
159 else
160 hpdp->pd = ((unsigned long)new & ~PD_HUGE) | pshift;
161#endif
162 spin_unlock(&mm->page_table_lock);
163 return 0;
164}
165
166/*
167 * These macros define how to determine which level of the page table holds
168 * the hpdp.
169 */
170#ifdef CONFIG_PPC_FSL_BOOK3E
171#define HUGEPD_PGD_SHIFT PGDIR_SHIFT
172#define HUGEPD_PUD_SHIFT PUD_SHIFT
173#else
174#define HUGEPD_PGD_SHIFT PUD_SHIFT
175#define HUGEPD_PUD_SHIFT PMD_SHIFT
176#endif
177
178pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz)
179{
180 pgd_t *pg;
181 pud_t *pu;
182 pmd_t *pm;
183 hugepd_t *hpdp = NULL;
184 unsigned pshift = __ffs(sz);
185 unsigned pdshift = PGDIR_SHIFT;
186
187 addr &= ~(sz-1);
188
189 pg = pgd_offset(mm, addr);
190
191 if (pshift >= HUGEPD_PGD_SHIFT) {
192 hpdp = (hugepd_t *)pg;
193 } else {
194 pdshift = PUD_SHIFT;
195 pu = pud_alloc(mm, pg, addr);
196 if (pshift >= HUGEPD_PUD_SHIFT) {
197 hpdp = (hugepd_t *)pu;
198 } else {
199 pdshift = PMD_SHIFT;
200 pm = pmd_alloc(mm, pu, addr);
201 hpdp = (hugepd_t *)pm;
202 }
203 }
204
205 if (!hpdp)
206 return NULL;
207
208 BUG_ON(!hugepd_none(*hpdp) && !hugepd_ok(*hpdp));
209
210 if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, pdshift, pshift))
211 return NULL;
212
213 return hugepte_offset(hpdp, addr, pdshift);
214}
215
216#ifdef CONFIG_PPC_FSL_BOOK3E
217/* Build list of addresses of gigantic pages. This function is used in early
218 * boot before the buddy or bootmem allocator is setup.
219 */
220void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages)
221{
222 unsigned int idx = shift_to_mmu_psize(__ffs(page_size));
223 int i;
224
225 if (addr == 0)
226 return;
227
228 gpage_freearray[idx].nr_gpages = number_of_pages;
229
230 for (i = 0; i < number_of_pages; i++) {
231 gpage_freearray[idx].gpage_list[i] = addr;
232 addr += page_size;
233 }
234}
235
236/*
237 * Moves the gigantic page addresses from the temporary list to the
238 * huge_boot_pages list.
239 */
240int alloc_bootmem_huge_page(struct hstate *hstate)
241{
242 struct huge_bootmem_page *m;
243 int idx = shift_to_mmu_psize(hstate->order + PAGE_SHIFT);
244 int nr_gpages = gpage_freearray[idx].nr_gpages;
245
246 if (nr_gpages == 0)
247 return 0;
248
249#ifdef CONFIG_HIGHMEM
250 /*
251 * If gpages can be in highmem we can't use the trick of storing the
252 * data structure in the page; allocate space for this
253 */
254 m = alloc_bootmem(sizeof(struct huge_bootmem_page));
255 m->phys = gpage_freearray[idx].gpage_list[--nr_gpages];
256#else
257 m = phys_to_virt(gpage_freearray[idx].gpage_list[--nr_gpages]);
258#endif
259
260 list_add(&m->list, &huge_boot_pages);
261 gpage_freearray[idx].nr_gpages = nr_gpages;
262 gpage_freearray[idx].gpage_list[nr_gpages] = 0;
263 m->hstate = hstate;
264
265 return 1;
266}
267/*
268 * Scan the command line hugepagesz= options for gigantic pages; store those in
269 * a list that we use to allocate the memory once all options are parsed.
270 */
271
272unsigned long gpage_npages[MMU_PAGE_COUNT];
273
274static int __init do_gpage_early_setup(char *param, char *val,
275 const char *unused)
276{
277 static phys_addr_t size;
278 unsigned long npages;
279
280 /*
281 * The hugepagesz and hugepages cmdline options are interleaved. We
282 * use the size variable to keep track of whether or not this was done
283 * properly and skip over instances where it is incorrect. Other
284 * command-line parsing code will issue warnings, so we don't need to.
285 *
286 */
287 if ((strcmp(param, "default_hugepagesz") == 0) ||
288 (strcmp(param, "hugepagesz") == 0)) {
289 size = memparse(val, NULL);
290 } else if (strcmp(param, "hugepages") == 0) {
291 if (size != 0) {
292 if (sscanf(val, "%lu", &npages) <= 0)
293 npages = 0;
294 gpage_npages[shift_to_mmu_psize(__ffs(size))] = npages;
295 size = 0;
296 }
297 }
298 return 0;
299}
300
301
302/*
303 * This function allocates physical space for pages that are larger than the
304 * buddy allocator can handle. We want to allocate these in highmem because
305 * the amount of lowmem is limited. This means that this function MUST be
306 * called before lowmem_end_addr is set up in MMU_init() in order for the lmb
307 * allocate to grab highmem.
308 */
309void __init reserve_hugetlb_gpages(void)
310{
311 static __initdata char cmdline[COMMAND_LINE_SIZE];
312 phys_addr_t size, base;
313 int i;
314
315 strlcpy(cmdline, boot_command_line, COMMAND_LINE_SIZE);
316 parse_args("hugetlb gpages", cmdline, NULL, 0, 0, 0,
317 &do_gpage_early_setup);
318
319 /*
320 * Walk gpage list in reverse, allocating larger page sizes first.
321 * Skip over unsupported sizes, or sizes that have 0 gpages allocated.
322 * When we reach the point in the list where pages are no longer
323 * considered gpages, we're done.
324 */
325 for (i = MMU_PAGE_COUNT-1; i >= 0; i--) {
326 if (mmu_psize_defs[i].shift == 0 || gpage_npages[i] == 0)
327 continue;
328 else if (mmu_psize_to_shift(i) < (MAX_ORDER + PAGE_SHIFT))
329 break;
330
331 size = (phys_addr_t)(1ULL << mmu_psize_to_shift(i));
332 base = memblock_alloc_base(size * gpage_npages[i], size,
333 MEMBLOCK_ALLOC_ANYWHERE);
334 add_gpage(base, size, gpage_npages[i]);
335 }
336}
337
338#else /* !PPC_FSL_BOOK3E */
339
340/* Build list of addresses of gigantic pages. This function is used in early
341 * boot before the buddy or bootmem allocator is setup.
342 */
343void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages)
344{
345 if (!addr)
346 return;
347 while (number_of_pages > 0) {
348 gpage_freearray[nr_gpages] = addr;
349 nr_gpages++;
350 number_of_pages--;
351 addr += page_size;
352 }
353}
354
355/* Moves the gigantic page addresses from the temporary list to the
356 * huge_boot_pages list.
357 */
358int alloc_bootmem_huge_page(struct hstate *hstate)
359{
360 struct huge_bootmem_page *m;
361 if (nr_gpages == 0)
362 return 0;
363 m = phys_to_virt(gpage_freearray[--nr_gpages]);
364 gpage_freearray[nr_gpages] = 0;
365 list_add(&m->list, &huge_boot_pages);
366 m->hstate = hstate;
367 return 1;
368}
369#endif
370
371int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
372{
373 return 0;
374}
375
376#ifdef CONFIG_PPC_FSL_BOOK3E
377#define HUGEPD_FREELIST_SIZE \
378 ((PAGE_SIZE - sizeof(struct hugepd_freelist)) / sizeof(pte_t))
379
380struct hugepd_freelist {
381 struct rcu_head rcu;
382 unsigned int index;
383 void *ptes[0];
384};
385
386static DEFINE_PER_CPU(struct hugepd_freelist *, hugepd_freelist_cur);
387
388static void hugepd_free_rcu_callback(struct rcu_head *head)
389{
390 struct hugepd_freelist *batch =
391 container_of(head, struct hugepd_freelist, rcu);
392 unsigned int i;
393
394 for (i = 0; i < batch->index; i++)
395 kmem_cache_free(hugepte_cache, batch->ptes[i]);
396
397 free_page((unsigned long)batch);
398}
399
400static void hugepd_free(struct mmu_gather *tlb, void *hugepte)
401{
402 struct hugepd_freelist **batchp;
403
404 batchp = &__get_cpu_var(hugepd_freelist_cur);
405
406 if (atomic_read(&tlb->mm->mm_users) < 2 ||
407 cpumask_equal(mm_cpumask(tlb->mm),
408 cpumask_of(smp_processor_id()))) {
409 kmem_cache_free(hugepte_cache, hugepte);
410 return;
411 }
412
413 if (*batchp == NULL) {
414 *batchp = (struct hugepd_freelist *)__get_free_page(GFP_ATOMIC);
415 (*batchp)->index = 0;
416 }
417
418 (*batchp)->ptes[(*batchp)->index++] = hugepte;
419 if ((*batchp)->index == HUGEPD_FREELIST_SIZE) {
420 call_rcu_sched(&(*batchp)->rcu, hugepd_free_rcu_callback);
421 *batchp = NULL;
422 }
423}
424#endif
425
426static void free_hugepd_range(struct mmu_gather *tlb, hugepd_t *hpdp, int pdshift,
427 unsigned long start, unsigned long end,
428 unsigned long floor, unsigned long ceiling)
429{
430 pte_t *hugepte = hugepd_page(*hpdp);
431 int i;
432
433 unsigned long pdmask = ~((1UL << pdshift) - 1);
434 unsigned int num_hugepd = 1;
435
436#ifdef CONFIG_PPC_FSL_BOOK3E
437 /* Note: On fsl the hpdp may be the first of several */
438 num_hugepd = (1 << (hugepd_shift(*hpdp) - pdshift));
439#else
440 unsigned int shift = hugepd_shift(*hpdp);
441#endif
442
443 start &= pdmask;
444 if (start < floor)
445 return;
446 if (ceiling) {
447 ceiling &= pdmask;
448 if (! ceiling)
449 return;
450 }
451 if (end - 1 > ceiling - 1)
452 return;
453
454 for (i = 0; i < num_hugepd; i++, hpdp++)
455 hpdp->pd = 0;
456
457 tlb->need_flush = 1;
458
459#ifdef CONFIG_PPC_FSL_BOOK3E
460 hugepd_free(tlb, hugepte);
461#else
462 pgtable_free_tlb(tlb, hugepte, pdshift - shift);
463#endif
464}
465
466static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
467 unsigned long addr, unsigned long end,
468 unsigned long floor, unsigned long ceiling)
469{
470 pmd_t *pmd;
471 unsigned long next;
472 unsigned long start;
473
474 start = addr;
475 do {
476 pmd = pmd_offset(pud, addr);
477 next = pmd_addr_end(addr, end);
478 if (pmd_none(*pmd))
479 continue;
480#ifdef CONFIG_PPC_FSL_BOOK3E
481 /*
482 * Increment next by the size of the huge mapping since
483 * there may be more than one entry at this level for a
484 * single hugepage, but all of them point to
485 * the same kmem cache that holds the hugepte.
486 */
487 next = addr + (1 << hugepd_shift(*(hugepd_t *)pmd));
488#endif
489 free_hugepd_range(tlb, (hugepd_t *)pmd, PMD_SHIFT,
490 addr, next, floor, ceiling);
491 } while (addr = next, addr != end);
492
493 start &= PUD_MASK;
494 if (start < floor)
495 return;
496 if (ceiling) {
497 ceiling &= PUD_MASK;
498 if (!ceiling)
499 return;
500 }
501 if (end - 1 > ceiling - 1)
502 return;
503
504 pmd = pmd_offset(pud, start);
505 pud_clear(pud);
506 pmd_free_tlb(tlb, pmd, start);
507}
508
509static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
510 unsigned long addr, unsigned long end,
511 unsigned long floor, unsigned long ceiling)
512{
513 pud_t *pud;
514 unsigned long next;
515 unsigned long start;
516
517 start = addr;
518 do {
519 pud = pud_offset(pgd, addr);
520 next = pud_addr_end(addr, end);
521 if (!is_hugepd(pud)) {
522 if (pud_none_or_clear_bad(pud))
523 continue;
524 hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
525 ceiling);
526 } else {
527#ifdef CONFIG_PPC_FSL_BOOK3E
528 /*
529 * Increment next by the size of the huge mapping since
530 * there may be more than one entry at this level for a
531 * single hugepage, but all of them point to
532 * the same kmem cache that holds the hugepte.
533 */
534 next = addr + (1 << hugepd_shift(*(hugepd_t *)pud));
535#endif
536 free_hugepd_range(tlb, (hugepd_t *)pud, PUD_SHIFT,
537 addr, next, floor, ceiling);
538 }
539 } while (addr = next, addr != end);
540
541 start &= PGDIR_MASK;
542 if (start < floor)
543 return;
544 if (ceiling) {
545 ceiling &= PGDIR_MASK;
546 if (!ceiling)
547 return;
548 }
549 if (end - 1 > ceiling - 1)
550 return;
551
552 pud = pud_offset(pgd, start);
553 pgd_clear(pgd);
554 pud_free_tlb(tlb, pud, start);
555}
556
557/*
558 * This function frees user-level page tables of a process.
559 *
560 * Must be called with pagetable lock held.
561 */
562void hugetlb_free_pgd_range(struct mmu_gather *tlb,
563 unsigned long addr, unsigned long end,
564 unsigned long floor, unsigned long ceiling)
565{
566 pgd_t *pgd;
567 unsigned long next;
568
569 /*
570 * Because there are a number of different possible pagetable
571 * layouts for hugepage ranges, we limit knowledge of how
572 * things should be laid out to the allocation path
573 * (huge_pte_alloc(), above). Everything else works out the
574 * structure as it goes from information in the hugepd
575 * pointers. That means that we can't here use the
576 * optimization used in the normal page free_pgd_range(), of
577 * checking whether we're actually covering a large enough
578 * range to have to do anything at the top level of the walk
579 * instead of at the bottom.
580 *
581 * To make sense of this, you should probably go read the big
582 * block comment at the top of the normal free_pgd_range(),
583 * too.
584 */
585
586 do {
587 next = pgd_addr_end(addr, end);
588 pgd = pgd_offset(tlb->mm, addr);
589 if (!is_hugepd(pgd)) {
590 if (pgd_none_or_clear_bad(pgd))
591 continue;
592 hugetlb_free_pud_range(tlb, pgd, addr, next, floor, ceiling);
593 } else {
594#ifdef CONFIG_PPC_FSL_BOOK3E
595 /*
596 * Increment next by the size of the huge mapping since
597 * there may be more than one entry at the pgd level
598 * for a single hugepage, but all of them point to the
599 * same kmem cache that holds the hugepte.
600 */
601 next = addr + (1 << hugepd_shift(*(hugepd_t *)pgd));
602#endif
603 free_hugepd_range(tlb, (hugepd_t *)pgd, PGDIR_SHIFT,
604 addr, next, floor, ceiling);
605 }
606 } while (addr = next, addr != end);
607}
608
609struct page *
610follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
611{
612 pte_t *ptep;
613 struct page *page;
614 unsigned shift;
615 unsigned long mask;
616
617 ptep = find_linux_pte_or_hugepte(mm->pgd, address, &shift);
618
619 /* Verify it is a huge page else bail. */
620 if (!ptep || !shift)
621 return ERR_PTR(-EINVAL);
622
623 mask = (1UL << shift) - 1;
624 page = pte_page(*ptep);
625 if (page)
626 page += (address & mask) / PAGE_SIZE;
627
628 return page;
629}
630
631int pmd_huge(pmd_t pmd)
632{
633 return 0;
634}
635
636int pud_huge(pud_t pud)
637{
638 return 0;
639}
640
641struct page *
642follow_huge_pmd(struct mm_struct *mm, unsigned long address,
643 pmd_t *pmd, int write)
644{
645 BUG();
646 return NULL;
647}
648
649static noinline int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
650 unsigned long end, int write, struct page **pages, int *nr)
651{
652 unsigned long mask;
653 unsigned long pte_end;
654 struct page *head, *page, *tail;
655 pte_t pte;
656 int refs;
657
658 pte_end = (addr + sz) & ~(sz-1);
659 if (pte_end < end)
660 end = pte_end;
661
662 pte = *ptep;
663 mask = _PAGE_PRESENT | _PAGE_USER;
664 if (write)
665 mask |= _PAGE_RW;
666
667 if ((pte_val(pte) & mask) != mask)
668 return 0;
669
670 /* hugepages are never "special" */
671 VM_BUG_ON(!pfn_valid(pte_pfn(pte)));
672
673 refs = 0;
674 head = pte_page(pte);
675
676 page = head + ((addr & (sz-1)) >> PAGE_SHIFT);
677 tail = page;
678 do {
679 VM_BUG_ON(compound_head(page) != head);
680 pages[*nr] = page;
681 (*nr)++;
682 page++;
683 refs++;
684 } while (addr += PAGE_SIZE, addr != end);
685
686 if (!page_cache_add_speculative(head, refs)) {
687 *nr -= refs;
688 return 0;
689 }
690
691 if (unlikely(pte_val(pte) != pte_val(*ptep))) {
692 /* Could be optimized better */
693 *nr -= refs;
694 while (refs--)
695 put_page(head);
696 return 0;
697 }
698
699 /*
700 * Any tail page need their mapcount reference taken before we
701 * return.
702 */
703 while (refs--) {
704 if (PageTail(tail))
705 get_huge_page_tail(tail);
706 tail++;
707 }
708
709 return 1;
710}
711
712static unsigned long hugepte_addr_end(unsigned long addr, unsigned long end,
713 unsigned long sz)
714{
715 unsigned long __boundary = (addr + sz) & ~(sz-1);
716 return (__boundary - 1 < end - 1) ? __boundary : end;
717}
718
719int gup_hugepd(hugepd_t *hugepd, unsigned pdshift,
720 unsigned long addr, unsigned long end,
721 int write, struct page **pages, int *nr)
722{
723 pte_t *ptep;
724 unsigned long sz = 1UL << hugepd_shift(*hugepd);
725 unsigned long next;
726
727 ptep = hugepte_offset(hugepd, addr, pdshift);
728 do {
729 next = hugepte_addr_end(addr, end, sz);
730 if (!gup_hugepte(ptep, sz, addr, end, write, pages, nr))
731 return 0;
732 } while (ptep++, addr = next, addr != end);
733
734 return 1;
735}
736
737#ifdef CONFIG_PPC_MM_SLICES
738unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
739 unsigned long len, unsigned long pgoff,
740 unsigned long flags)
741{
742 struct hstate *hstate = hstate_file(file);
743 int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate));
744
745 return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1, 0);
746}
747#endif
748
749unsigned long vma_mmu_pagesize(struct vm_area_struct *vma)
750{
751#ifdef CONFIG_PPC_MM_SLICES
752 unsigned int psize = get_slice_psize(vma->vm_mm, vma->vm_start);
753
754 return 1UL << mmu_psize_to_shift(psize);
755#else
756 if (!is_vm_hugetlb_page(vma))
757 return PAGE_SIZE;
758
759 return huge_page_size(hstate_vma(vma));
760#endif
761}
762
763static inline bool is_power_of_4(unsigned long x)
764{
765 if (is_power_of_2(x))
766 return (__ilog2(x) % 2) ? false : true;
767 return false;
768}
769
770static int __init add_huge_page_size(unsigned long long size)
771{
772 int shift = __ffs(size);
773 int mmu_psize;
774
775 /* Check that it is a page size supported by the hardware and
776 * that it fits within pagetable and slice limits. */
777#ifdef CONFIG_PPC_FSL_BOOK3E
778 if ((size < PAGE_SIZE) || !is_power_of_4(size))
779 return -EINVAL;
780#else
781 if (!is_power_of_2(size)
782 || (shift > SLICE_HIGH_SHIFT) || (shift <= PAGE_SHIFT))
783 return -EINVAL;
784#endif
785
786 if ((mmu_psize = shift_to_mmu_psize(shift)) < 0)
787 return -EINVAL;
788
789#ifdef CONFIG_SPU_FS_64K_LS
790 /* Disable support for 64K huge pages when 64K SPU local store
791 * support is enabled as the current implementation conflicts.
792 */
793 if (shift == PAGE_SHIFT_64K)
794 return -EINVAL;
795#endif /* CONFIG_SPU_FS_64K_LS */
796
797 BUG_ON(mmu_psize_defs[mmu_psize].shift != shift);
798
799 /* Return if huge page size has already been setup */
800 if (size_to_hstate(size))
801 return 0;
802
803 hugetlb_add_hstate(shift - PAGE_SHIFT);
804
805 return 0;
806}
807
808static int __init hugepage_setup_sz(char *str)
809{
810 unsigned long long size;
811
812 size = memparse(str, &str);
813
814 if (add_huge_page_size(size) != 0)
815 printk(KERN_WARNING "Invalid huge page size specified(%llu)\n", size);
816
817 return 1;
818}
819__setup("hugepagesz=", hugepage_setup_sz);
820
821#ifdef CONFIG_PPC_FSL_BOOK3E
822struct kmem_cache *hugepte_cache;
823static int __init hugetlbpage_init(void)
824{
825 int psize;
826
827 for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
828 unsigned shift;
829
830 if (!mmu_psize_defs[psize].shift)
831 continue;
832
833 shift = mmu_psize_to_shift(psize);
834
835 /* Don't treat normal page sizes as huge... */
836 if (shift != PAGE_SHIFT)
837 if (add_huge_page_size(1ULL << shift) < 0)
838 continue;
839 }
840
841 /*
842 * Create a kmem cache for hugeptes. The bottom bits in the pte have
843 * size information encoded in them, so align them to allow this
844 */
845 hugepte_cache = kmem_cache_create("hugepte-cache", sizeof(pte_t),
846 HUGEPD_SHIFT_MASK + 1, 0, NULL);
847 if (hugepte_cache == NULL)
848 panic("%s: Unable to create kmem cache for hugeptes\n",
849 __func__);
850
851 /* Default hpage size = 4M */
852 if (mmu_psize_defs[MMU_PAGE_4M].shift)
853 HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_4M].shift;
854 else
855 panic("%s: Unable to set default huge page size\n", __func__);
856
857
858 return 0;
859}
860#else
861static int __init hugetlbpage_init(void)
862{
863 int psize;
864
865 if (!mmu_has_feature(MMU_FTR_16M_PAGE))
866 return -ENODEV;
867
868 for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
869 unsigned shift;
870 unsigned pdshift;
871
872 if (!mmu_psize_defs[psize].shift)
873 continue;
874
875 shift = mmu_psize_to_shift(psize);
876
877 if (add_huge_page_size(1ULL << shift) < 0)
878 continue;
879
880 if (shift < PMD_SHIFT)
881 pdshift = PMD_SHIFT;
882 else if (shift < PUD_SHIFT)
883 pdshift = PUD_SHIFT;
884 else
885 pdshift = PGDIR_SHIFT;
886
887 pgtable_cache_add(pdshift - shift, NULL);
888 if (!PGT_CACHE(pdshift - shift))
889 panic("hugetlbpage_init(): could not create "
890 "pgtable cache for %d bit pagesize\n", shift);
891 }
892
893 /* Set default large page size. Currently, we pick 16M or 1M
894 * depending on what is available
895 */
896 if (mmu_psize_defs[MMU_PAGE_16M].shift)
897 HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_16M].shift;
898 else if (mmu_psize_defs[MMU_PAGE_1M].shift)
899 HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_1M].shift;
900
901 return 0;
902}
903#endif
904module_init(hugetlbpage_init);
905
906void flush_dcache_icache_hugepage(struct page *page)
907{
908 int i;
909 void *start;
910
911 BUG_ON(!PageCompound(page));
912
913 for (i = 0; i < (1UL << compound_order(page)); i++) {
914 if (!PageHighMem(page)) {
915 __flush_dcache_icache(page_address(page+i));
916 } else {
917 start = kmap_atomic(page+i);
918 __flush_dcache_icache(start);
919 kunmap_atomic(start);
920 }
921 }
922}