Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 2 | * PPC Huge TLB Page Support for Kernel. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3 | * |
| 4 | * Copyright (C) 2003 David Gibson, IBM Corporation. |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 5 | * Copyright (C) 2011 Becky Bruce, Freescale Semiconductor |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 6 | * |
| 7 | * Based on the IA-32 version: |
| 8 | * Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com> |
| 9 | */ |
| 10 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | #include <linux/mm.h> |
David Gibson | 883a3e5 | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 12 | #include <linux/io.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 13 | #include <linux/slab.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | #include <linux/hugetlb.h> |
Paul Mackerras | 342d3db | 2011-12-12 12:38:05 +0000 | [diff] [blame] | 15 | #include <linux/export.h> |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 16 | #include <linux/of_fdt.h> |
| 17 | #include <linux/memblock.h> |
| 18 | #include <linux/bootmem.h> |
Kumar Gala | 13020be | 2011-11-24 09:40:07 +0000 | [diff] [blame] | 19 | #include <linux/moduleparam.h> |
David Gibson | 883a3e5 | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 20 | #include <asm/pgtable.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | #include <asm/pgalloc.h> |
| 22 | #include <asm/tlb.h> |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 23 | #include <asm/setup.h> |
Aneesh Kumar K.V | 2940999 | 2013-06-20 14:30:16 +0530 | [diff] [blame] | 24 | #include <asm/hugetlb.h> |
| 25 | |
| 26 | #ifdef CONFIG_HUGETLB_PAGE |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | |
Jon Tollefson | 9122434 | 2008-07-23 21:27:55 -0700 | [diff] [blame] | 28 | #define PAGE_SHIFT_64K 16 |
| 29 | #define PAGE_SHIFT_16M 24 |
| 30 | #define PAGE_SHIFT_16G 34 |
Jon Tollefson | 4ec161c | 2008-01-04 09:59:50 +1100 | [diff] [blame] | 31 | |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 32 | unsigned int HPAGE_SHIFT; |
| 33 | |
| 34 | /* |
| 35 | * Tracks gpages after the device tree is scanned and before the |
Becky Bruce | a614688 | 2011-10-10 10:50:43 +0000 | [diff] [blame] | 36 | * huge_boot_pages list is ready. On non-Freescale implementations, this is |
| 37 | * just used to track 16G pages and so is a single array. FSL-based |
| 38 | * implementations may have more than one gpage size, so we need multiple |
| 39 | * arrays |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 40 | */ |
Becky Bruce | 881fde1 | 2011-10-10 10:50:40 +0000 | [diff] [blame] | 41 | #ifdef CONFIG_PPC_FSL_BOOK3E |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 42 | #define MAX_NUMBER_GPAGES 128 |
| 43 | struct psize_gpages { |
| 44 | u64 gpage_list[MAX_NUMBER_GPAGES]; |
| 45 | unsigned int nr_gpages; |
| 46 | }; |
| 47 | static struct psize_gpages gpage_freearray[MMU_PAGE_COUNT]; |
Becky Bruce | 881fde1 | 2011-10-10 10:50:40 +0000 | [diff] [blame] | 48 | #else |
| 49 | #define MAX_NUMBER_GPAGES 1024 |
| 50 | static u64 gpage_freearray[MAX_NUMBER_GPAGES]; |
| 51 | static unsigned nr_gpages; |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 52 | #endif |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 53 | |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 54 | #define hugepd_none(hpd) ((hpd).pd == 0) |
| 55 | |
Aneesh Kumar K.V | e2b3d20 | 2013-04-28 09:37:30 +0000 | [diff] [blame] | 56 | #ifdef CONFIG_PPC_BOOK3S_64 |
| 57 | /* |
| 58 | * At this point we do the placement change only for BOOK3S 64. This would |
| 59 | * possibly work on other subarchs. |
| 60 | */ |
| 61 | |
| 62 | /* |
| 63 | * We have PGD_INDEX_SIZ = 12 and PTE_INDEX_SIZE = 8, so that we can have |
| 64 | * 16GB hugepage pte in PGD and 16MB hugepage pte at PMD; |
Aneesh Kumar K.V | 0674352 | 2014-11-05 21:57:39 +0530 | [diff] [blame] | 65 | * |
| 66 | * Defined in such a way that we can optimize away code block at build time |
| 67 | * if CONFIG_HUGETLB_PAGE=n. |
Aneesh Kumar K.V | e2b3d20 | 2013-04-28 09:37:30 +0000 | [diff] [blame] | 68 | */ |
| 69 | int pmd_huge(pmd_t pmd) |
| 70 | { |
| 71 | /* |
| 72 | * leaf pte for huge page, bottom two bits != 00 |
| 73 | */ |
| 74 | return ((pmd_val(pmd) & 0x3) != 0x0); |
| 75 | } |
| 76 | |
| 77 | int pud_huge(pud_t pud) |
| 78 | { |
| 79 | /* |
| 80 | * leaf pte for huge page, bottom two bits != 00 |
| 81 | */ |
| 82 | return ((pud_val(pud) & 0x3) != 0x0); |
| 83 | } |
| 84 | |
| 85 | int pgd_huge(pgd_t pgd) |
| 86 | { |
| 87 | /* |
| 88 | * leaf pte for huge page, bottom two bits != 00 |
| 89 | */ |
| 90 | return ((pgd_val(pgd) & 0x3) != 0x0); |
| 91 | } |
| 92 | #else |
| 93 | int pmd_huge(pmd_t pmd) |
| 94 | { |
| 95 | return 0; |
| 96 | } |
| 97 | |
| 98 | int pud_huge(pud_t pud) |
| 99 | { |
| 100 | return 0; |
| 101 | } |
| 102 | |
| 103 | int pgd_huge(pgd_t pgd) |
| 104 | { |
| 105 | return 0; |
| 106 | } |
| 107 | #endif |
| 108 | |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 109 | pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) |
| 110 | { |
Aneesh Kumar K.V | 12bc9f6 | 2013-06-20 14:30:18 +0530 | [diff] [blame] | 111 | /* Only called for hugetlbfs pages, hence can ignore THP */ |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 112 | return find_linux_pte_or_hugepte(mm->pgd, addr, NULL); |
| 113 | } |
| 114 | |
| 115 | static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp, |
| 116 | unsigned long address, unsigned pdshift, unsigned pshift) |
| 117 | { |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 118 | struct kmem_cache *cachep; |
| 119 | pte_t *new; |
| 120 | |
Becky Bruce | 881fde1 | 2011-10-10 10:50:40 +0000 | [diff] [blame] | 121 | #ifdef CONFIG_PPC_FSL_BOOK3E |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 122 | int i; |
| 123 | int num_hugepd = 1 << (pshift - pdshift); |
| 124 | cachep = hugepte_cache; |
Becky Bruce | 881fde1 | 2011-10-10 10:50:40 +0000 | [diff] [blame] | 125 | #else |
| 126 | cachep = PGT_CACHE(pdshift - pshift); |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 127 | #endif |
| 128 | |
| 129 | new = kmem_cache_zalloc(cachep, GFP_KERNEL|__GFP_REPEAT); |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 130 | |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 131 | BUG_ON(pshift > HUGEPD_SHIFT_MASK); |
| 132 | BUG_ON((unsigned long)new & HUGEPD_SHIFT_MASK); |
| 133 | |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 134 | if (! new) |
| 135 | return -ENOMEM; |
| 136 | |
| 137 | spin_lock(&mm->page_table_lock); |
Becky Bruce | 881fde1 | 2011-10-10 10:50:40 +0000 | [diff] [blame] | 138 | #ifdef CONFIG_PPC_FSL_BOOK3E |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 139 | /* |
| 140 | * We have multiple higher-level entries that point to the same |
| 141 | * actual pte location. Fill in each as we go and backtrack on error. |
| 142 | * We need all of these so the DTLB pgtable walk code can find the |
| 143 | * right higher-level entry without knowing if it's a hugepage or not. |
| 144 | */ |
| 145 | for (i = 0; i < num_hugepd; i++, hpdp++) { |
| 146 | if (unlikely(!hugepd_none(*hpdp))) |
| 147 | break; |
| 148 | else |
Aneesh Kumar K.V | cf9427b | 2013-04-28 09:37:29 +0000 | [diff] [blame] | 149 | /* We use the old format for PPC_FSL_BOOK3E */ |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 150 | hpdp->pd = ((unsigned long)new & ~PD_HUGE) | pshift; |
| 151 | } |
| 152 | /* If we bailed from the for loop early, an error occurred, clean up */ |
| 153 | if (i < num_hugepd) { |
| 154 | for (i = i - 1 ; i >= 0; i--, hpdp--) |
| 155 | hpdp->pd = 0; |
| 156 | kmem_cache_free(cachep, new); |
| 157 | } |
Becky Bruce | a1cd541 | 2011-10-10 10:50:39 +0000 | [diff] [blame] | 158 | #else |
| 159 | if (!hugepd_none(*hpdp)) |
| 160 | kmem_cache_free(cachep, new); |
Aneesh Kumar K.V | cf9427b | 2013-04-28 09:37:29 +0000 | [diff] [blame] | 161 | else { |
| 162 | #ifdef CONFIG_PPC_BOOK3S_64 |
| 163 | hpdp->pd = (unsigned long)new | |
| 164 | (shift_to_mmu_psize(pshift) << 2); |
| 165 | #else |
Becky Bruce | a1cd541 | 2011-10-10 10:50:39 +0000 | [diff] [blame] | 166 | hpdp->pd = ((unsigned long)new & ~PD_HUGE) | pshift; |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 167 | #endif |
Aneesh Kumar K.V | cf9427b | 2013-04-28 09:37:29 +0000 | [diff] [blame] | 168 | } |
| 169 | #endif |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 170 | spin_unlock(&mm->page_table_lock); |
| 171 | return 0; |
| 172 | } |
| 173 | |
Becky Bruce | a1cd541 | 2011-10-10 10:50:39 +0000 | [diff] [blame] | 174 | /* |
| 175 | * These macros define how to determine which level of the page table holds |
| 176 | * the hpdp. |
| 177 | */ |
| 178 | #ifdef CONFIG_PPC_FSL_BOOK3E |
| 179 | #define HUGEPD_PGD_SHIFT PGDIR_SHIFT |
| 180 | #define HUGEPD_PUD_SHIFT PUD_SHIFT |
| 181 | #else |
| 182 | #define HUGEPD_PGD_SHIFT PUD_SHIFT |
| 183 | #define HUGEPD_PUD_SHIFT PMD_SHIFT |
| 184 | #endif |
| 185 | |
Aneesh Kumar K.V | e2b3d20 | 2013-04-28 09:37:30 +0000 | [diff] [blame] | 186 | #ifdef CONFIG_PPC_BOOK3S_64 |
| 187 | /* |
| 188 | * At this point we do the placement change only for BOOK3S 64. This would |
| 189 | * possibly work on other subarchs. |
| 190 | */ |
| 191 | pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz) |
| 192 | { |
| 193 | pgd_t *pg; |
| 194 | pud_t *pu; |
| 195 | pmd_t *pm; |
| 196 | hugepd_t *hpdp = NULL; |
| 197 | unsigned pshift = __ffs(sz); |
| 198 | unsigned pdshift = PGDIR_SHIFT; |
| 199 | |
| 200 | addr &= ~(sz-1); |
| 201 | pg = pgd_offset(mm, addr); |
| 202 | |
| 203 | if (pshift == PGDIR_SHIFT) |
| 204 | /* 16GB huge page */ |
| 205 | return (pte_t *) pg; |
| 206 | else if (pshift > PUD_SHIFT) |
| 207 | /* |
| 208 | * We need to use hugepd table |
| 209 | */ |
| 210 | hpdp = (hugepd_t *)pg; |
| 211 | else { |
| 212 | pdshift = PUD_SHIFT; |
| 213 | pu = pud_alloc(mm, pg, addr); |
| 214 | if (pshift == PUD_SHIFT) |
| 215 | return (pte_t *)pu; |
| 216 | else if (pshift > PMD_SHIFT) |
| 217 | hpdp = (hugepd_t *)pu; |
| 218 | else { |
| 219 | pdshift = PMD_SHIFT; |
| 220 | pm = pmd_alloc(mm, pu, addr); |
| 221 | if (pshift == PMD_SHIFT) |
| 222 | /* 16MB hugepage */ |
| 223 | return (pte_t *)pm; |
| 224 | else |
| 225 | hpdp = (hugepd_t *)pm; |
| 226 | } |
| 227 | } |
| 228 | if (!hpdp) |
| 229 | return NULL; |
| 230 | |
| 231 | BUG_ON(!hugepd_none(*hpdp) && !hugepd_ok(*hpdp)); |
| 232 | |
| 233 | if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, pdshift, pshift)) |
| 234 | return NULL; |
| 235 | |
Aneesh Kumar K.V | b30e759 | 2014-11-05 21:57:41 +0530 | [diff] [blame] | 236 | return hugepte_offset(*hpdp, addr, pdshift); |
Aneesh Kumar K.V | e2b3d20 | 2013-04-28 09:37:30 +0000 | [diff] [blame] | 237 | } |
| 238 | |
| 239 | #else |
| 240 | |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 241 | pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz) |
| 242 | { |
| 243 | pgd_t *pg; |
| 244 | pud_t *pu; |
| 245 | pmd_t *pm; |
| 246 | hugepd_t *hpdp = NULL; |
| 247 | unsigned pshift = __ffs(sz); |
| 248 | unsigned pdshift = PGDIR_SHIFT; |
David Gibson | 0b26425 | 2008-09-05 11:49:54 +1000 | [diff] [blame] | 249 | |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 250 | addr &= ~(sz-1); |
| 251 | |
| 252 | pg = pgd_offset(mm, addr); |
Becky Bruce | a1cd541 | 2011-10-10 10:50:39 +0000 | [diff] [blame] | 253 | |
| 254 | if (pshift >= HUGEPD_PGD_SHIFT) { |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 255 | hpdp = (hugepd_t *)pg; |
| 256 | } else { |
| 257 | pdshift = PUD_SHIFT; |
| 258 | pu = pud_alloc(mm, pg, addr); |
Becky Bruce | a1cd541 | 2011-10-10 10:50:39 +0000 | [diff] [blame] | 259 | if (pshift >= HUGEPD_PUD_SHIFT) { |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 260 | hpdp = (hugepd_t *)pu; |
| 261 | } else { |
| 262 | pdshift = PMD_SHIFT; |
| 263 | pm = pmd_alloc(mm, pu, addr); |
| 264 | hpdp = (hugepd_t *)pm; |
| 265 | } |
| 266 | } |
| 267 | |
| 268 | if (!hpdp) |
| 269 | return NULL; |
| 270 | |
| 271 | BUG_ON(!hugepd_none(*hpdp) && !hugepd_ok(*hpdp)); |
| 272 | |
| 273 | if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, pdshift, pshift)) |
| 274 | return NULL; |
| 275 | |
Aneesh Kumar K.V | b30e759 | 2014-11-05 21:57:41 +0530 | [diff] [blame] | 276 | return hugepte_offset(*hpdp, addr, pdshift); |
Jon Tollefson | 4ec161c | 2008-01-04 09:59:50 +1100 | [diff] [blame] | 277 | } |
Aneesh Kumar K.V | e2b3d20 | 2013-04-28 09:37:30 +0000 | [diff] [blame] | 278 | #endif |
Jon Tollefson | 4ec161c | 2008-01-04 09:59:50 +1100 | [diff] [blame] | 279 | |
Becky Bruce | 881fde1 | 2011-10-10 10:50:40 +0000 | [diff] [blame] | 280 | #ifdef CONFIG_PPC_FSL_BOOK3E |
Jon Tollefson | 658013e | 2008-07-23 21:27:54 -0700 | [diff] [blame] | 281 | /* Build list of addresses of gigantic pages. This function is used in early |
Anton Blanchard | 14ed740 | 2014-09-17 22:15:34 +1000 | [diff] [blame] | 282 | * boot before the buddy allocator is setup. |
Jon Tollefson | 658013e | 2008-07-23 21:27:54 -0700 | [diff] [blame] | 283 | */ |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 284 | void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages) |
| 285 | { |
| 286 | unsigned int idx = shift_to_mmu_psize(__ffs(page_size)); |
| 287 | int i; |
| 288 | |
| 289 | if (addr == 0) |
| 290 | return; |
| 291 | |
| 292 | gpage_freearray[idx].nr_gpages = number_of_pages; |
| 293 | |
| 294 | for (i = 0; i < number_of_pages; i++) { |
| 295 | gpage_freearray[idx].gpage_list[i] = addr; |
| 296 | addr += page_size; |
| 297 | } |
| 298 | } |
| 299 | |
| 300 | /* |
| 301 | * Moves the gigantic page addresses from the temporary list to the |
| 302 | * huge_boot_pages list. |
| 303 | */ |
| 304 | int alloc_bootmem_huge_page(struct hstate *hstate) |
| 305 | { |
| 306 | struct huge_bootmem_page *m; |
Wanpeng Li | 2415cf1 | 2013-07-03 15:02:43 -0700 | [diff] [blame] | 307 | int idx = shift_to_mmu_psize(huge_page_shift(hstate)); |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 308 | int nr_gpages = gpage_freearray[idx].nr_gpages; |
| 309 | |
| 310 | if (nr_gpages == 0) |
| 311 | return 0; |
| 312 | |
| 313 | #ifdef CONFIG_HIGHMEM |
| 314 | /* |
| 315 | * If gpages can be in highmem we can't use the trick of storing the |
| 316 | * data structure in the page; allocate space for this |
| 317 | */ |
Michael Ellerman | e39f223f | 2014-11-18 16:47:35 +1100 | [diff] [blame] | 318 | m = memblock_virt_alloc(sizeof(struct huge_bootmem_page), 0); |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 319 | m->phys = gpage_freearray[idx].gpage_list[--nr_gpages]; |
| 320 | #else |
| 321 | m = phys_to_virt(gpage_freearray[idx].gpage_list[--nr_gpages]); |
| 322 | #endif |
| 323 | |
| 324 | list_add(&m->list, &huge_boot_pages); |
| 325 | gpage_freearray[idx].nr_gpages = nr_gpages; |
| 326 | gpage_freearray[idx].gpage_list[nr_gpages] = 0; |
| 327 | m->hstate = hstate; |
| 328 | |
| 329 | return 1; |
| 330 | } |
| 331 | /* |
| 332 | * Scan the command line hugepagesz= options for gigantic pages; store those in |
| 333 | * a list that we use to allocate the memory once all options are parsed. |
| 334 | */ |
| 335 | |
| 336 | unsigned long gpage_npages[MMU_PAGE_COUNT]; |
| 337 | |
Paul Gortmaker | 8952812 | 2012-05-07 10:32:22 -0400 | [diff] [blame] | 338 | static int __init do_gpage_early_setup(char *param, char *val, |
| 339 | const char *unused) |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 340 | { |
| 341 | static phys_addr_t size; |
| 342 | unsigned long npages; |
| 343 | |
| 344 | /* |
| 345 | * The hugepagesz and hugepages cmdline options are interleaved. We |
| 346 | * use the size variable to keep track of whether or not this was done |
| 347 | * properly and skip over instances where it is incorrect. Other |
| 348 | * command-line parsing code will issue warnings, so we don't need to. |
| 349 | * |
| 350 | */ |
| 351 | if ((strcmp(param, "default_hugepagesz") == 0) || |
| 352 | (strcmp(param, "hugepagesz") == 0)) { |
| 353 | size = memparse(val, NULL); |
| 354 | } else if (strcmp(param, "hugepages") == 0) { |
| 355 | if (size != 0) { |
| 356 | if (sscanf(val, "%lu", &npages) <= 0) |
| 357 | npages = 0; |
James Yang | c4f3eb5 | 2014-11-14 12:32:24 -0600 | [diff] [blame] | 358 | if (npages > MAX_NUMBER_GPAGES) { |
| 359 | pr_warn("MMU: %lu pages requested for page " |
| 360 | "size %llu KB, limiting to " |
| 361 | __stringify(MAX_NUMBER_GPAGES) "\n", |
| 362 | npages, size / 1024); |
| 363 | npages = MAX_NUMBER_GPAGES; |
| 364 | } |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 365 | gpage_npages[shift_to_mmu_psize(__ffs(size))] = npages; |
| 366 | size = 0; |
| 367 | } |
| 368 | } |
| 369 | return 0; |
| 370 | } |
| 371 | |
| 372 | |
| 373 | /* |
| 374 | * This function allocates physical space for pages that are larger than the |
| 375 | * buddy allocator can handle. We want to allocate these in highmem because |
| 376 | * the amount of lowmem is limited. This means that this function MUST be |
| 377 | * called before lowmem_end_addr is set up in MMU_init() in order for the lmb |
| 378 | * allocate to grab highmem. |
| 379 | */ |
| 380 | void __init reserve_hugetlb_gpages(void) |
| 381 | { |
| 382 | static __initdata char cmdline[COMMAND_LINE_SIZE]; |
| 383 | phys_addr_t size, base; |
| 384 | int i; |
| 385 | |
| 386 | strlcpy(cmdline, boot_command_line, COMMAND_LINE_SIZE); |
Pawel Moll | 026cee0 | 2012-03-26 12:50:51 +1030 | [diff] [blame] | 387 | parse_args("hugetlb gpages", cmdline, NULL, 0, 0, 0, |
| 388 | &do_gpage_early_setup); |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 389 | |
| 390 | /* |
| 391 | * Walk gpage list in reverse, allocating larger page sizes first. |
| 392 | * Skip over unsupported sizes, or sizes that have 0 gpages allocated. |
| 393 | * When we reach the point in the list where pages are no longer |
| 394 | * considered gpages, we're done. |
| 395 | */ |
| 396 | for (i = MMU_PAGE_COUNT-1; i >= 0; i--) { |
| 397 | if (mmu_psize_defs[i].shift == 0 || gpage_npages[i] == 0) |
| 398 | continue; |
| 399 | else if (mmu_psize_to_shift(i) < (MAX_ORDER + PAGE_SHIFT)) |
| 400 | break; |
| 401 | |
| 402 | size = (phys_addr_t)(1ULL << mmu_psize_to_shift(i)); |
| 403 | base = memblock_alloc_base(size * gpage_npages[i], size, |
| 404 | MEMBLOCK_ALLOC_ANYWHERE); |
| 405 | add_gpage(base, size, gpage_npages[i]); |
| 406 | } |
| 407 | } |
| 408 | |
Becky Bruce | 881fde1 | 2011-10-10 10:50:40 +0000 | [diff] [blame] | 409 | #else /* !PPC_FSL_BOOK3E */ |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 410 | |
| 411 | /* Build list of addresses of gigantic pages. This function is used in early |
Anton Blanchard | 14ed740 | 2014-09-17 22:15:34 +1000 | [diff] [blame] | 412 | * boot before the buddy allocator is setup. |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 413 | */ |
| 414 | void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages) |
Jon Tollefson | 658013e | 2008-07-23 21:27:54 -0700 | [diff] [blame] | 415 | { |
| 416 | if (!addr) |
| 417 | return; |
| 418 | while (number_of_pages > 0) { |
| 419 | gpage_freearray[nr_gpages] = addr; |
| 420 | nr_gpages++; |
| 421 | number_of_pages--; |
| 422 | addr += page_size; |
| 423 | } |
| 424 | } |
| 425 | |
Jon Tollefson | ec4b2c0 | 2008-07-23 21:27:53 -0700 | [diff] [blame] | 426 | /* Moves the gigantic page addresses from the temporary list to the |
Jon Tollefson | 0d9ea75 | 2008-07-23 21:27:56 -0700 | [diff] [blame] | 427 | * huge_boot_pages list. |
| 428 | */ |
| 429 | int alloc_bootmem_huge_page(struct hstate *hstate) |
Jon Tollefson | ec4b2c0 | 2008-07-23 21:27:53 -0700 | [diff] [blame] | 430 | { |
| 431 | struct huge_bootmem_page *m; |
| 432 | if (nr_gpages == 0) |
| 433 | return 0; |
| 434 | m = phys_to_virt(gpage_freearray[--nr_gpages]); |
| 435 | gpage_freearray[nr_gpages] = 0; |
| 436 | list_add(&m->list, &huge_boot_pages); |
Jon Tollefson | 0d9ea75 | 2008-07-23 21:27:56 -0700 | [diff] [blame] | 437 | m->hstate = hstate; |
Jon Tollefson | ec4b2c0 | 2008-07-23 21:27:53 -0700 | [diff] [blame] | 438 | return 1; |
| 439 | } |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 440 | #endif |
Jon Tollefson | ec4b2c0 | 2008-07-23 21:27:53 -0700 | [diff] [blame] | 441 | |
Chen, Kenneth W | 39dde65 | 2006-12-06 20:32:03 -0800 | [diff] [blame] | 442 | int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep) |
| 443 | { |
| 444 | return 0; |
| 445 | } |
| 446 | |
Becky Bruce | 881fde1 | 2011-10-10 10:50:40 +0000 | [diff] [blame] | 447 | #ifdef CONFIG_PPC_FSL_BOOK3E |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 448 | #define HUGEPD_FREELIST_SIZE \ |
| 449 | ((PAGE_SIZE - sizeof(struct hugepd_freelist)) / sizeof(pte_t)) |
| 450 | |
| 451 | struct hugepd_freelist { |
| 452 | struct rcu_head rcu; |
| 453 | unsigned int index; |
| 454 | void *ptes[0]; |
| 455 | }; |
| 456 | |
| 457 | static DEFINE_PER_CPU(struct hugepd_freelist *, hugepd_freelist_cur); |
| 458 | |
| 459 | static void hugepd_free_rcu_callback(struct rcu_head *head) |
| 460 | { |
| 461 | struct hugepd_freelist *batch = |
| 462 | container_of(head, struct hugepd_freelist, rcu); |
| 463 | unsigned int i; |
| 464 | |
| 465 | for (i = 0; i < batch->index; i++) |
| 466 | kmem_cache_free(hugepte_cache, batch->ptes[i]); |
| 467 | |
| 468 | free_page((unsigned long)batch); |
| 469 | } |
| 470 | |
| 471 | static void hugepd_free(struct mmu_gather *tlb, void *hugepte) |
| 472 | { |
| 473 | struct hugepd_freelist **batchp; |
| 474 | |
Christoph Lameter | 69111ba | 2014-10-21 15:23:25 -0500 | [diff] [blame] | 475 | batchp = this_cpu_ptr(&hugepd_freelist_cur); |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 476 | |
| 477 | if (atomic_read(&tlb->mm->mm_users) < 2 || |
| 478 | cpumask_equal(mm_cpumask(tlb->mm), |
| 479 | cpumask_of(smp_processor_id()))) { |
| 480 | kmem_cache_free(hugepte_cache, hugepte); |
Tiejun Chen | 94b09d7 | 2014-01-20 16:39:34 +0800 | [diff] [blame] | 481 | put_cpu_var(hugepd_freelist_cur); |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 482 | return; |
| 483 | } |
| 484 | |
| 485 | if (*batchp == NULL) { |
| 486 | *batchp = (struct hugepd_freelist *)__get_free_page(GFP_ATOMIC); |
| 487 | (*batchp)->index = 0; |
| 488 | } |
| 489 | |
| 490 | (*batchp)->ptes[(*batchp)->index++] = hugepte; |
| 491 | if ((*batchp)->index == HUGEPD_FREELIST_SIZE) { |
| 492 | call_rcu_sched(&(*batchp)->rcu, hugepd_free_rcu_callback); |
| 493 | *batchp = NULL; |
| 494 | } |
Tiejun Chen | 94b09d7 | 2014-01-20 16:39:34 +0800 | [diff] [blame] | 495 | put_cpu_var(hugepd_freelist_cur); |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 496 | } |
| 497 | #endif |
| 498 | |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 499 | static void free_hugepd_range(struct mmu_gather *tlb, hugepd_t *hpdp, int pdshift, |
| 500 | unsigned long start, unsigned long end, |
| 501 | unsigned long floor, unsigned long ceiling) |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 502 | { |
| 503 | pte_t *hugepte = hugepd_page(*hpdp); |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 504 | int i; |
| 505 | |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 506 | unsigned long pdmask = ~((1UL << pdshift) - 1); |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 507 | unsigned int num_hugepd = 1; |
| 508 | |
Becky Bruce | 881fde1 | 2011-10-10 10:50:40 +0000 | [diff] [blame] | 509 | #ifdef CONFIG_PPC_FSL_BOOK3E |
| 510 | /* Note: On fsl the hpdp may be the first of several */ |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 511 | num_hugepd = (1 << (hugepd_shift(*hpdp) - pdshift)); |
Becky Bruce | 881fde1 | 2011-10-10 10:50:40 +0000 | [diff] [blame] | 512 | #else |
| 513 | unsigned int shift = hugepd_shift(*hpdp); |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 514 | #endif |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 515 | |
| 516 | start &= pdmask; |
| 517 | if (start < floor) |
| 518 | return; |
| 519 | if (ceiling) { |
| 520 | ceiling &= pdmask; |
| 521 | if (! ceiling) |
| 522 | return; |
| 523 | } |
| 524 | if (end - 1 > ceiling - 1) |
| 525 | return; |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 526 | |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 527 | for (i = 0; i < num_hugepd; i++, hpdp++) |
| 528 | hpdp->pd = 0; |
| 529 | |
Becky Bruce | 881fde1 | 2011-10-10 10:50:40 +0000 | [diff] [blame] | 530 | #ifdef CONFIG_PPC_FSL_BOOK3E |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 531 | hugepd_free(tlb, hugepte); |
Becky Bruce | 881fde1 | 2011-10-10 10:50:40 +0000 | [diff] [blame] | 532 | #else |
| 533 | pgtable_free_tlb(tlb, hugepte, pdshift - shift); |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 534 | #endif |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 535 | } |
| 536 | |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 537 | static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud, |
| 538 | unsigned long addr, unsigned long end, |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 539 | unsigned long floor, unsigned long ceiling) |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 540 | { |
| 541 | pmd_t *pmd; |
| 542 | unsigned long next; |
| 543 | unsigned long start; |
| 544 | |
| 545 | start = addr; |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 546 | do { |
Becky Bruce | a1cd541 | 2011-10-10 10:50:39 +0000 | [diff] [blame] | 547 | pmd = pmd_offset(pud, addr); |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 548 | next = pmd_addr_end(addr, end); |
Aneesh Kumar K.V | b30e759 | 2014-11-05 21:57:41 +0530 | [diff] [blame] | 549 | if (!is_hugepd(__hugepd(pmd_val(*pmd)))) { |
Aneesh Kumar K.V | 8bbd9f0 | 2013-06-19 12:04:26 +0530 | [diff] [blame] | 550 | /* |
| 551 | * if it is not hugepd pointer, we should already find |
| 552 | * it cleared. |
| 553 | */ |
| 554 | WARN_ON(!pmd_none_or_clear_bad(pmd)); |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 555 | continue; |
Aneesh Kumar K.V | 8bbd9f0 | 2013-06-19 12:04:26 +0530 | [diff] [blame] | 556 | } |
Becky Bruce | a1cd541 | 2011-10-10 10:50:39 +0000 | [diff] [blame] | 557 | #ifdef CONFIG_PPC_FSL_BOOK3E |
| 558 | /* |
| 559 | * Increment next by the size of the huge mapping since |
| 560 | * there may be more than one entry at this level for a |
| 561 | * single hugepage, but all of them point to |
| 562 | * the same kmem cache that holds the hugepte. |
| 563 | */ |
| 564 | next = addr + (1 << hugepd_shift(*(hugepd_t *)pmd)); |
| 565 | #endif |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 566 | free_hugepd_range(tlb, (hugepd_t *)pmd, PMD_SHIFT, |
| 567 | addr, next, floor, ceiling); |
Becky Bruce | a1cd541 | 2011-10-10 10:50:39 +0000 | [diff] [blame] | 568 | } while (addr = next, addr != end); |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 569 | |
| 570 | start &= PUD_MASK; |
| 571 | if (start < floor) |
| 572 | return; |
| 573 | if (ceiling) { |
| 574 | ceiling &= PUD_MASK; |
| 575 | if (!ceiling) |
| 576 | return; |
| 577 | } |
| 578 | if (end - 1 > ceiling - 1) |
| 579 | return; |
| 580 | |
| 581 | pmd = pmd_offset(pud, start); |
| 582 | pud_clear(pud); |
Benjamin Herrenschmidt | 9e1b32c | 2009-07-22 15:44:28 +1000 | [diff] [blame] | 583 | pmd_free_tlb(tlb, pmd, start); |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 584 | } |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 585 | |
| 586 | static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd, |
| 587 | unsigned long addr, unsigned long end, |
| 588 | unsigned long floor, unsigned long ceiling) |
| 589 | { |
| 590 | pud_t *pud; |
| 591 | unsigned long next; |
| 592 | unsigned long start; |
| 593 | |
| 594 | start = addr; |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 595 | do { |
Becky Bruce | a1cd541 | 2011-10-10 10:50:39 +0000 | [diff] [blame] | 596 | pud = pud_offset(pgd, addr); |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 597 | next = pud_addr_end(addr, end); |
Aneesh Kumar K.V | b30e759 | 2014-11-05 21:57:41 +0530 | [diff] [blame] | 598 | if (!is_hugepd(__hugepd(pud_val(*pud)))) { |
Jon Tollefson | 4ec161c | 2008-01-04 09:59:50 +1100 | [diff] [blame] | 599 | if (pud_none_or_clear_bad(pud)) |
| 600 | continue; |
Jon Tollefson | 0d9ea75 | 2008-07-23 21:27:56 -0700 | [diff] [blame] | 601 | hugetlb_free_pmd_range(tlb, pud, addr, next, floor, |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 602 | ceiling); |
Jon Tollefson | 4ec161c | 2008-01-04 09:59:50 +1100 | [diff] [blame] | 603 | } else { |
Becky Bruce | a1cd541 | 2011-10-10 10:50:39 +0000 | [diff] [blame] | 604 | #ifdef CONFIG_PPC_FSL_BOOK3E |
| 605 | /* |
| 606 | * Increment next by the size of the huge mapping since |
| 607 | * there may be more than one entry at this level for a |
| 608 | * single hugepage, but all of them point to |
| 609 | * the same kmem cache that holds the hugepte. |
| 610 | */ |
| 611 | next = addr + (1 << hugepd_shift(*(hugepd_t *)pud)); |
| 612 | #endif |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 613 | free_hugepd_range(tlb, (hugepd_t *)pud, PUD_SHIFT, |
| 614 | addr, next, floor, ceiling); |
Jon Tollefson | 4ec161c | 2008-01-04 09:59:50 +1100 | [diff] [blame] | 615 | } |
Becky Bruce | a1cd541 | 2011-10-10 10:50:39 +0000 | [diff] [blame] | 616 | } while (addr = next, addr != end); |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 617 | |
| 618 | start &= PGDIR_MASK; |
| 619 | if (start < floor) |
| 620 | return; |
| 621 | if (ceiling) { |
| 622 | ceiling &= PGDIR_MASK; |
| 623 | if (!ceiling) |
| 624 | return; |
| 625 | } |
| 626 | if (end - 1 > ceiling - 1) |
| 627 | return; |
| 628 | |
| 629 | pud = pud_offset(pgd, start); |
| 630 | pgd_clear(pgd); |
Benjamin Herrenschmidt | 9e1b32c | 2009-07-22 15:44:28 +1000 | [diff] [blame] | 631 | pud_free_tlb(tlb, pud, start); |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 632 | } |
| 633 | |
| 634 | /* |
| 635 | * This function frees user-level page tables of a process. |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 636 | */ |
Jan Beulich | 42b7772 | 2008-07-23 21:27:10 -0700 | [diff] [blame] | 637 | void hugetlb_free_pgd_range(struct mmu_gather *tlb, |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 638 | unsigned long addr, unsigned long end, |
| 639 | unsigned long floor, unsigned long ceiling) |
| 640 | { |
| 641 | pgd_t *pgd; |
| 642 | unsigned long next; |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 643 | |
| 644 | /* |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 645 | * Because there are a number of different possible pagetable |
| 646 | * layouts for hugepage ranges, we limit knowledge of how |
| 647 | * things should be laid out to the allocation path |
| 648 | * (huge_pte_alloc(), above). Everything else works out the |
| 649 | * structure as it goes from information in the hugepd |
| 650 | * pointers. That means that we can't here use the |
| 651 | * optimization used in the normal page free_pgd_range(), of |
| 652 | * checking whether we're actually covering a large enough |
| 653 | * range to have to do anything at the top level of the walk |
| 654 | * instead of at the bottom. |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 655 | * |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 656 | * To make sense of this, you should probably go read the big |
| 657 | * block comment at the top of the normal free_pgd_range(), |
| 658 | * too. |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 659 | */ |
| 660 | |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 661 | do { |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 662 | next = pgd_addr_end(addr, end); |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 663 | pgd = pgd_offset(tlb->mm, addr); |
Aneesh Kumar K.V | b30e759 | 2014-11-05 21:57:41 +0530 | [diff] [blame] | 664 | if (!is_hugepd(__hugepd(pgd_val(*pgd)))) { |
David Gibson | 0b26425 | 2008-09-05 11:49:54 +1000 | [diff] [blame] | 665 | if (pgd_none_or_clear_bad(pgd)) |
| 666 | continue; |
| 667 | hugetlb_free_pud_range(tlb, pgd, addr, next, floor, ceiling); |
| 668 | } else { |
Becky Bruce | 881fde1 | 2011-10-10 10:50:40 +0000 | [diff] [blame] | 669 | #ifdef CONFIG_PPC_FSL_BOOK3E |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 670 | /* |
| 671 | * Increment next by the size of the huge mapping since |
Becky Bruce | 881fde1 | 2011-10-10 10:50:40 +0000 | [diff] [blame] | 672 | * there may be more than one entry at the pgd level |
| 673 | * for a single hugepage, but all of them point to the |
| 674 | * same kmem cache that holds the hugepte. |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 675 | */ |
| 676 | next = addr + (1 << hugepd_shift(*(hugepd_t *)pgd)); |
| 677 | #endif |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 678 | free_hugepd_range(tlb, (hugepd_t *)pgd, PGDIR_SHIFT, |
| 679 | addr, next, floor, ceiling); |
David Gibson | 0b26425 | 2008-09-05 11:49:54 +1000 | [diff] [blame] | 680 | } |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 681 | } while (addr = next, addr != end); |
David Gibson | e28f7fa | 2005-08-05 19:39:06 +1000 | [diff] [blame] | 682 | } |
| 683 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 684 | struct page * |
| 685 | follow_huge_addr(struct mm_struct *mm, unsigned long address, int write) |
| 686 | { |
| 687 | pte_t *ptep; |
| 688 | struct page *page; |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 689 | unsigned shift; |
| 690 | unsigned long mask; |
Aneesh Kumar K.V | 12bc9f6 | 2013-06-20 14:30:18 +0530 | [diff] [blame] | 691 | /* |
| 692 | * Transparent hugepages are handled by generic code. We can skip them |
| 693 | * here. |
| 694 | */ |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 695 | ptep = find_linux_pte_or_hugepte(mm->pgd, address, &shift); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 696 | |
Jon Tollefson | 0d9ea75 | 2008-07-23 21:27:56 -0700 | [diff] [blame] | 697 | /* Verify it is a huge page else bail. */ |
Aneesh Kumar K.V | 12bc9f6 | 2013-06-20 14:30:18 +0530 | [diff] [blame] | 698 | if (!ptep || !shift || pmd_trans_huge(*(pmd_t *)ptep)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 699 | return ERR_PTR(-EINVAL); |
| 700 | |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 701 | mask = (1UL << shift) - 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 702 | page = pte_page(*ptep); |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 703 | if (page) |
| 704 | page += (address & mask) / PAGE_SIZE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 705 | |
| 706 | return page; |
| 707 | } |
| 708 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 709 | struct page * |
| 710 | follow_huge_pmd(struct mm_struct *mm, unsigned long address, |
| 711 | pmd_t *pmd, int write) |
| 712 | { |
| 713 | BUG(); |
| 714 | return NULL; |
| 715 | } |
| 716 | |
Naoya Horiguchi | 61f77ed | 2015-02-11 15:25:15 -0800 | [diff] [blame] | 717 | struct page * |
| 718 | follow_huge_pud(struct mm_struct *mm, unsigned long address, |
| 719 | pud_t *pud, int write) |
| 720 | { |
| 721 | BUG(); |
| 722 | return NULL; |
| 723 | } |
| 724 | |
David Gibson | 39adfa5 | 2009-11-23 20:03:40 +0000 | [diff] [blame] | 725 | static unsigned long hugepte_addr_end(unsigned long addr, unsigned long end, |
| 726 | unsigned long sz) |
| 727 | { |
| 728 | unsigned long __boundary = (addr + sz) & ~(sz-1); |
| 729 | return (__boundary - 1 < end - 1) ? __boundary : end; |
| 730 | } |
| 731 | |
Aneesh Kumar K.V | b30e759 | 2014-11-05 21:57:41 +0530 | [diff] [blame] | 732 | int gup_huge_pd(hugepd_t hugepd, unsigned long addr, unsigned pdshift, |
| 733 | unsigned long end, int write, struct page **pages, int *nr) |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 734 | { |
| 735 | pte_t *ptep; |
Aneesh Kumar K.V | b30e759 | 2014-11-05 21:57:41 +0530 | [diff] [blame] | 736 | unsigned long sz = 1UL << hugepd_shift(hugepd); |
David Gibson | 39adfa5 | 2009-11-23 20:03:40 +0000 | [diff] [blame] | 737 | unsigned long next; |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 738 | |
| 739 | ptep = hugepte_offset(hugepd, addr, pdshift); |
| 740 | do { |
David Gibson | 39adfa5 | 2009-11-23 20:03:40 +0000 | [diff] [blame] | 741 | next = hugepte_addr_end(addr, end, sz); |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 742 | if (!gup_hugepte(ptep, sz, addr, end, write, pages, nr)) |
| 743 | return 0; |
David Gibson | 39adfa5 | 2009-11-23 20:03:40 +0000 | [diff] [blame] | 744 | } while (ptep++, addr = next, addr != end); |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 745 | |
| 746 | return 1; |
| 747 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 748 | |
Becky Bruce | 7651295 | 2011-10-10 10:50:36 +0000 | [diff] [blame] | 749 | #ifdef CONFIG_PPC_MM_SLICES |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 750 | unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, |
| 751 | unsigned long len, unsigned long pgoff, |
| 752 | unsigned long flags) |
| 753 | { |
Jon Tollefson | 0d9ea75 | 2008-07-23 21:27:56 -0700 | [diff] [blame] | 754 | struct hstate *hstate = hstate_file(file); |
| 755 | int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate)); |
Brian King | 48f797d | 2008-12-04 04:07:54 +0000 | [diff] [blame] | 756 | |
Michel Lespinasse | 34d0717 | 2013-04-29 11:53:52 -0700 | [diff] [blame] | 757 | return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 758 | } |
Becky Bruce | 7651295 | 2011-10-10 10:50:36 +0000 | [diff] [blame] | 759 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 760 | |
Mel Gorman | 3340289 | 2009-01-06 14:38:54 -0800 | [diff] [blame] | 761 | unsigned long vma_mmu_pagesize(struct vm_area_struct *vma) |
| 762 | { |
Paul Mackerras | 25c29f9 | 2011-09-20 19:58:10 +0000 | [diff] [blame] | 763 | #ifdef CONFIG_PPC_MM_SLICES |
Mel Gorman | 3340289 | 2009-01-06 14:38:54 -0800 | [diff] [blame] | 764 | unsigned int psize = get_slice_psize(vma->vm_mm, vma->vm_start); |
| 765 | |
| 766 | return 1UL << mmu_psize_to_shift(psize); |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 767 | #else |
| 768 | if (!is_vm_hugetlb_page(vma)) |
| 769 | return PAGE_SIZE; |
| 770 | |
| 771 | return huge_page_size(hstate_vma(vma)); |
| 772 | #endif |
| 773 | } |
| 774 | |
| 775 | static inline bool is_power_of_4(unsigned long x) |
| 776 | { |
| 777 | if (is_power_of_2(x)) |
| 778 | return (__ilog2(x) % 2) ? false : true; |
| 779 | return false; |
Mel Gorman | 3340289 | 2009-01-06 14:38:54 -0800 | [diff] [blame] | 780 | } |
| 781 | |
David Gibson | d1837cb | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 782 | static int __init add_huge_page_size(unsigned long long size) |
Jon Tollefson | 4ec161c | 2008-01-04 09:59:50 +1100 | [diff] [blame] | 783 | { |
David Gibson | d1837cb | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 784 | int shift = __ffs(size); |
| 785 | int mmu_psize; |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 786 | |
Jon Tollefson | 4ec161c | 2008-01-04 09:59:50 +1100 | [diff] [blame] | 787 | /* Check that it is a page size supported by the hardware and |
David Gibson | d1837cb | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 788 | * that it fits within pagetable and slice limits. */ |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 789 | #ifdef CONFIG_PPC_FSL_BOOK3E |
| 790 | if ((size < PAGE_SIZE) || !is_power_of_4(size)) |
| 791 | return -EINVAL; |
| 792 | #else |
David Gibson | d1837cb | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 793 | if (!is_power_of_2(size) |
| 794 | || (shift > SLICE_HIGH_SHIFT) || (shift <= PAGE_SHIFT)) |
| 795 | return -EINVAL; |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 796 | #endif |
Jon Tollefson | 9122434 | 2008-07-23 21:27:55 -0700 | [diff] [blame] | 797 | |
David Gibson | d1837cb | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 798 | if ((mmu_psize = shift_to_mmu_psize(shift)) < 0) |
| 799 | return -EINVAL; |
| 800 | |
| 801 | #ifdef CONFIG_SPU_FS_64K_LS |
| 802 | /* Disable support for 64K huge pages when 64K SPU local store |
| 803 | * support is enabled as the current implementation conflicts. |
| 804 | */ |
| 805 | if (shift == PAGE_SHIFT_64K) |
| 806 | return -EINVAL; |
| 807 | #endif /* CONFIG_SPU_FS_64K_LS */ |
| 808 | |
| 809 | BUG_ON(mmu_psize_defs[mmu_psize].shift != shift); |
| 810 | |
| 811 | /* Return if huge page size has already been setup */ |
| 812 | if (size_to_hstate(size)) |
| 813 | return 0; |
| 814 | |
| 815 | hugetlb_add_hstate(shift - PAGE_SHIFT); |
| 816 | |
| 817 | return 0; |
Jon Tollefson | 4ec161c | 2008-01-04 09:59:50 +1100 | [diff] [blame] | 818 | } |
| 819 | |
| 820 | static int __init hugepage_setup_sz(char *str) |
| 821 | { |
| 822 | unsigned long long size; |
Jon Tollefson | 4ec161c | 2008-01-04 09:59:50 +1100 | [diff] [blame] | 823 | |
| 824 | size = memparse(str, &str); |
| 825 | |
David Gibson | d1837cb | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 826 | if (add_huge_page_size(size) != 0) |
Jon Tollefson | 4ec161c | 2008-01-04 09:59:50 +1100 | [diff] [blame] | 827 | printk(KERN_WARNING "Invalid huge page size specified(%llu)\n", size); |
| 828 | |
| 829 | return 1; |
| 830 | } |
| 831 | __setup("hugepagesz=", hugepage_setup_sz); |
| 832 | |
Becky Bruce | 881fde1 | 2011-10-10 10:50:40 +0000 | [diff] [blame] | 833 | #ifdef CONFIG_PPC_FSL_BOOK3E |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 834 | struct kmem_cache *hugepte_cache; |
| 835 | static int __init hugetlbpage_init(void) |
| 836 | { |
| 837 | int psize; |
| 838 | |
| 839 | for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) { |
| 840 | unsigned shift; |
| 841 | |
| 842 | if (!mmu_psize_defs[psize].shift) |
| 843 | continue; |
| 844 | |
| 845 | shift = mmu_psize_to_shift(psize); |
| 846 | |
| 847 | /* Don't treat normal page sizes as huge... */ |
| 848 | if (shift != PAGE_SHIFT) |
| 849 | if (add_huge_page_size(1ULL << shift) < 0) |
| 850 | continue; |
| 851 | } |
| 852 | |
| 853 | /* |
| 854 | * Create a kmem cache for hugeptes. The bottom bits in the pte have |
| 855 | * size information encoded in them, so align them to allow this |
| 856 | */ |
| 857 | hugepte_cache = kmem_cache_create("hugepte-cache", sizeof(pte_t), |
| 858 | HUGEPD_SHIFT_MASK + 1, 0, NULL); |
| 859 | if (hugepte_cache == NULL) |
| 860 | panic("%s: Unable to create kmem cache for hugeptes\n", |
| 861 | __func__); |
| 862 | |
| 863 | /* Default hpage size = 4M */ |
| 864 | if (mmu_psize_defs[MMU_PAGE_4M].shift) |
| 865 | HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_4M].shift; |
| 866 | else |
| 867 | panic("%s: Unable to set default huge page size\n", __func__); |
| 868 | |
| 869 | |
| 870 | return 0; |
| 871 | } |
| 872 | #else |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 873 | static int __init hugetlbpage_init(void) |
| 874 | { |
David Gibson | a4fe3ce | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 875 | int psize; |
Jon Tollefson | 0d9ea75 | 2008-07-23 21:27:56 -0700 | [diff] [blame] | 876 | |
Matt Evans | 44ae3ab | 2011-04-06 19:48:50 +0000 | [diff] [blame] | 877 | if (!mmu_has_feature(MMU_FTR_16M_PAGE)) |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 878 | return -ENODEV; |
Benjamin Herrenschmidt | 00df438 | 2008-07-28 16:13:18 +1000 | [diff] [blame] | 879 | |
Jon Tollefson | 0d9ea75 | 2008-07-23 21:27:56 -0700 | [diff] [blame] | 880 | for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) { |
David Gibson | d1837cb | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 881 | unsigned shift; |
| 882 | unsigned pdshift; |
| 883 | |
| 884 | if (!mmu_psize_defs[psize].shift) |
| 885 | continue; |
| 886 | |
| 887 | shift = mmu_psize_to_shift(psize); |
| 888 | |
| 889 | if (add_huge_page_size(1ULL << shift) < 0) |
| 890 | continue; |
| 891 | |
| 892 | if (shift < PMD_SHIFT) |
| 893 | pdshift = PMD_SHIFT; |
| 894 | else if (shift < PUD_SHIFT) |
| 895 | pdshift = PUD_SHIFT; |
| 896 | else |
| 897 | pdshift = PGDIR_SHIFT; |
Aneesh Kumar K.V | e2b3d20 | 2013-04-28 09:37:30 +0000 | [diff] [blame] | 898 | /* |
| 899 | * if we have pdshift and shift value same, we don't |
| 900 | * use pgt cache for hugepd. |
| 901 | */ |
| 902 | if (pdshift != shift) { |
| 903 | pgtable_cache_add(pdshift - shift, NULL); |
| 904 | if (!PGT_CACHE(pdshift - shift)) |
| 905 | panic("hugetlbpage_init(): could not create " |
| 906 | "pgtable cache for %d bit pagesize\n", shift); |
| 907 | } |
Jon Tollefson | 0d9ea75 | 2008-07-23 21:27:56 -0700 | [diff] [blame] | 908 | } |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 909 | |
David Gibson | d1837cb | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 910 | /* Set default large page size. Currently, we pick 16M or 1M |
| 911 | * depending on what is available |
| 912 | */ |
| 913 | if (mmu_psize_defs[MMU_PAGE_16M].shift) |
| 914 | HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_16M].shift; |
| 915 | else if (mmu_psize_defs[MMU_PAGE_1M].shift) |
| 916 | HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_1M].shift; |
| 917 | |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 918 | return 0; |
| 919 | } |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 920 | #endif |
David Gibson | f10a04c | 2006-04-28 15:02:51 +1000 | [diff] [blame] | 921 | module_init(hugetlbpage_init); |
David Gibson | 0895ecd | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 922 | |
| 923 | void flush_dcache_icache_hugepage(struct page *page) |
| 924 | { |
| 925 | int i; |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 926 | void *start; |
David Gibson | 0895ecd | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 927 | |
| 928 | BUG_ON(!PageCompound(page)); |
| 929 | |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 930 | for (i = 0; i < (1UL << compound_order(page)); i++) { |
| 931 | if (!PageHighMem(page)) { |
| 932 | __flush_dcache_icache(page_address(page+i)); |
| 933 | } else { |
Cong Wang | 2480b20 | 2011-11-25 23:14:16 +0800 | [diff] [blame] | 934 | start = kmap_atomic(page+i); |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 935 | __flush_dcache_icache(start); |
Cong Wang | 2480b20 | 2011-11-25 23:14:16 +0800 | [diff] [blame] | 936 | kunmap_atomic(start); |
Becky Bruce | 41151e7 | 2011-06-28 09:54:48 +0000 | [diff] [blame] | 937 | } |
| 938 | } |
David Gibson | 0895ecd | 2009-10-26 19:24:31 +0000 | [diff] [blame] | 939 | } |
Aneesh Kumar K.V | 2940999 | 2013-06-20 14:30:16 +0530 | [diff] [blame] | 940 | |
| 941 | #endif /* CONFIG_HUGETLB_PAGE */ |
| 942 | |
| 943 | /* |
| 944 | * We have 4 cases for pgds and pmds: |
| 945 | * (1) invalid (all zeroes) |
| 946 | * (2) pointer to next table, as normal; bottom 6 bits == 0 |
| 947 | * (3) leaf pte for huge page, bottom two bits != 00 |
| 948 | * (4) hugepd pointer, bottom two bits == 00, next 4 bits indicate size of table |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 949 | * |
| 950 | * So long as we atomically load page table pointers we are safe against teardown, |
| 951 | * we can follow the address down to the the page and take a ref on it. |
Aneesh Kumar K.V | 2940999 | 2013-06-20 14:30:16 +0530 | [diff] [blame] | 952 | */ |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 953 | |
Aneesh Kumar K.V | 2940999 | 2013-06-20 14:30:16 +0530 | [diff] [blame] | 954 | pte_t *find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea, unsigned *shift) |
| 955 | { |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 956 | pgd_t pgd, *pgdp; |
| 957 | pud_t pud, *pudp; |
| 958 | pmd_t pmd, *pmdp; |
Aneesh Kumar K.V | 2940999 | 2013-06-20 14:30:16 +0530 | [diff] [blame] | 959 | pte_t *ret_pte; |
| 960 | hugepd_t *hpdp = NULL; |
| 961 | unsigned pdshift = PGDIR_SHIFT; |
| 962 | |
| 963 | if (shift) |
| 964 | *shift = 0; |
| 965 | |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 966 | pgdp = pgdir + pgd_index(ea); |
Michael Ellerman | 4f9c53c | 2015-03-25 20:11:57 +1100 | [diff] [blame^] | 967 | pgd = READ_ONCE(*pgdp); |
Aneesh Kumar K.V | ac52ae4 | 2013-06-20 14:30:17 +0530 | [diff] [blame] | 968 | /* |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 969 | * Always operate on the local stack value. This make sure the |
| 970 | * value don't get updated by a parallel THP split/collapse, |
| 971 | * page fault or a page unmap. The return pte_t * is still not |
| 972 | * stable. So should be checked there for above conditions. |
Aneesh Kumar K.V | ac52ae4 | 2013-06-20 14:30:17 +0530 | [diff] [blame] | 973 | */ |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 974 | if (pgd_none(pgd)) |
Aneesh Kumar K.V | ac52ae4 | 2013-06-20 14:30:17 +0530 | [diff] [blame] | 975 | return NULL; |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 976 | else if (pgd_huge(pgd)) { |
| 977 | ret_pte = (pte_t *) pgdp; |
Aneesh Kumar K.V | 2940999 | 2013-06-20 14:30:16 +0530 | [diff] [blame] | 978 | goto out; |
Aneesh Kumar K.V | b30e759 | 2014-11-05 21:57:41 +0530 | [diff] [blame] | 979 | } else if (is_hugepd(__hugepd(pgd_val(pgd)))) |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 980 | hpdp = (hugepd_t *)&pgd; |
Aneesh Kumar K.V | ac52ae4 | 2013-06-20 14:30:17 +0530 | [diff] [blame] | 981 | else { |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 982 | /* |
| 983 | * Even if we end up with an unmap, the pgtable will not |
| 984 | * be freed, because we do an rcu free and here we are |
| 985 | * irq disabled |
| 986 | */ |
Aneesh Kumar K.V | 2940999 | 2013-06-20 14:30:16 +0530 | [diff] [blame] | 987 | pdshift = PUD_SHIFT; |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 988 | pudp = pud_offset(&pgd, ea); |
Christian Borntraeger | da1a288 | 2015-01-06 22:47:41 +0100 | [diff] [blame] | 989 | pud = READ_ONCE(*pudp); |
Aneesh Kumar K.V | 2940999 | 2013-06-20 14:30:16 +0530 | [diff] [blame] | 990 | |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 991 | if (pud_none(pud)) |
Aneesh Kumar K.V | ac52ae4 | 2013-06-20 14:30:17 +0530 | [diff] [blame] | 992 | return NULL; |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 993 | else if (pud_huge(pud)) { |
| 994 | ret_pte = (pte_t *) pudp; |
Aneesh Kumar K.V | 2940999 | 2013-06-20 14:30:16 +0530 | [diff] [blame] | 995 | goto out; |
Aneesh Kumar K.V | b30e759 | 2014-11-05 21:57:41 +0530 | [diff] [blame] | 996 | } else if (is_hugepd(__hugepd(pud_val(pud)))) |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 997 | hpdp = (hugepd_t *)&pud; |
Aneesh Kumar K.V | ac52ae4 | 2013-06-20 14:30:17 +0530 | [diff] [blame] | 998 | else { |
Aneesh Kumar K.V | 2940999 | 2013-06-20 14:30:16 +0530 | [diff] [blame] | 999 | pdshift = PMD_SHIFT; |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 1000 | pmdp = pmd_offset(&pud, ea); |
Christian Borntraeger | da1a288 | 2015-01-06 22:47:41 +0100 | [diff] [blame] | 1001 | pmd = READ_ONCE(*pmdp); |
Aneesh Kumar K.V | ac52ae4 | 2013-06-20 14:30:17 +0530 | [diff] [blame] | 1002 | /* |
| 1003 | * A hugepage collapse is captured by pmd_none, because |
| 1004 | * it mark the pmd none and do a hpte invalidate. |
| 1005 | * |
| 1006 | * A hugepage split is captured by pmd_trans_splitting |
| 1007 | * because we mark the pmd trans splitting and do a |
| 1008 | * hpte invalidate |
| 1009 | * |
| 1010 | */ |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 1011 | if (pmd_none(pmd) || pmd_trans_splitting(pmd)) |
Aneesh Kumar K.V | ac52ae4 | 2013-06-20 14:30:17 +0530 | [diff] [blame] | 1012 | return NULL; |
Aneesh Kumar K.V | 2940999 | 2013-06-20 14:30:16 +0530 | [diff] [blame] | 1013 | |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 1014 | if (pmd_huge(pmd) || pmd_large(pmd)) { |
| 1015 | ret_pte = (pte_t *) pmdp; |
Aneesh Kumar K.V | 2940999 | 2013-06-20 14:30:16 +0530 | [diff] [blame] | 1016 | goto out; |
Aneesh Kumar K.V | b30e759 | 2014-11-05 21:57:41 +0530 | [diff] [blame] | 1017 | } else if (is_hugepd(__hugepd(pmd_val(pmd)))) |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 1018 | hpdp = (hugepd_t *)&pmd; |
Aneesh Kumar K.V | ac52ae4 | 2013-06-20 14:30:17 +0530 | [diff] [blame] | 1019 | else |
Aneesh Kumar K.V | 0ac52dd | 2013-06-20 14:30:22 +0530 | [diff] [blame] | 1020 | return pte_offset_kernel(&pmd, ea); |
Aneesh Kumar K.V | 2940999 | 2013-06-20 14:30:16 +0530 | [diff] [blame] | 1021 | } |
| 1022 | } |
| 1023 | if (!hpdp) |
| 1024 | return NULL; |
| 1025 | |
Aneesh Kumar K.V | b30e759 | 2014-11-05 21:57:41 +0530 | [diff] [blame] | 1026 | ret_pte = hugepte_offset(*hpdp, ea, pdshift); |
Aneesh Kumar K.V | 2940999 | 2013-06-20 14:30:16 +0530 | [diff] [blame] | 1027 | pdshift = hugepd_shift(*hpdp); |
| 1028 | out: |
| 1029 | if (shift) |
| 1030 | *shift = pdshift; |
| 1031 | return ret_pte; |
| 1032 | } |
| 1033 | EXPORT_SYMBOL_GPL(find_linux_pte_or_hugepte); |
| 1034 | |
| 1035 | int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr, |
| 1036 | unsigned long end, int write, struct page **pages, int *nr) |
| 1037 | { |
| 1038 | unsigned long mask; |
| 1039 | unsigned long pte_end; |
| 1040 | struct page *head, *page, *tail; |
| 1041 | pte_t pte; |
| 1042 | int refs; |
| 1043 | |
| 1044 | pte_end = (addr + sz) & ~(sz-1); |
| 1045 | if (pte_end < end) |
| 1046 | end = pte_end; |
| 1047 | |
Michael Ellerman | 4f9c53c | 2015-03-25 20:11:57 +1100 | [diff] [blame^] | 1048 | pte = READ_ONCE(*ptep); |
Aneesh Kumar K.V | 2940999 | 2013-06-20 14:30:16 +0530 | [diff] [blame] | 1049 | mask = _PAGE_PRESENT | _PAGE_USER; |
| 1050 | if (write) |
| 1051 | mask |= _PAGE_RW; |
| 1052 | |
| 1053 | if ((pte_val(pte) & mask) != mask) |
| 1054 | return 0; |
| 1055 | |
| 1056 | /* hugepages are never "special" */ |
| 1057 | VM_BUG_ON(!pfn_valid(pte_pfn(pte))); |
| 1058 | |
| 1059 | refs = 0; |
| 1060 | head = pte_page(pte); |
| 1061 | |
| 1062 | page = head + ((addr & (sz-1)) >> PAGE_SHIFT); |
| 1063 | tail = page; |
| 1064 | do { |
| 1065 | VM_BUG_ON(compound_head(page) != head); |
| 1066 | pages[*nr] = page; |
| 1067 | (*nr)++; |
| 1068 | page++; |
| 1069 | refs++; |
| 1070 | } while (addr += PAGE_SIZE, addr != end); |
| 1071 | |
| 1072 | if (!page_cache_add_speculative(head, refs)) { |
| 1073 | *nr -= refs; |
| 1074 | return 0; |
| 1075 | } |
| 1076 | |
| 1077 | if (unlikely(pte_val(pte) != pte_val(*ptep))) { |
| 1078 | /* Could be optimized better */ |
| 1079 | *nr -= refs; |
| 1080 | while (refs--) |
| 1081 | put_page(head); |
| 1082 | return 0; |
| 1083 | } |
| 1084 | |
| 1085 | /* |
| 1086 | * Any tail page need their mapcount reference taken before we |
| 1087 | * return. |
| 1088 | */ |
| 1089 | while (refs--) { |
| 1090 | if (PageTail(tail)) |
| 1091 | get_huge_page_tail(tail); |
| 1092 | tail++; |
| 1093 | } |
| 1094 | |
| 1095 | return 1; |
| 1096 | } |