Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Simple NUMA memory policy for the Linux kernel. |
| 3 | * |
| 4 | * Copyright 2003,2004 Andi Kleen, SuSE Labs. |
| 5 | * Subject to the GNU Public License, version 2. |
| 6 | * |
| 7 | * NUMA policy allows the user to give hints in which node(s) memory should |
| 8 | * be allocated. |
| 9 | * |
| 10 | * Support four policies per VMA and per process: |
| 11 | * |
| 12 | * The VMA policy has priority over the process policy for a page fault. |
| 13 | * |
| 14 | * interleave Allocate memory interleaved over a set of nodes, |
| 15 | * with normal fallback if it fails. |
| 16 | * For VMA based allocations this interleaves based on the |
| 17 | * offset into the backing object or offset into the mapping |
| 18 | * for anonymous memory. For process policy an process counter |
| 19 | * is used. |
| 20 | * bind Only allocate memory on a specific set of nodes, |
| 21 | * no fallback. |
| 22 | * preferred Try a specific node first before normal fallback. |
| 23 | * As a special case node -1 here means do the allocation |
| 24 | * on the local CPU. This is normally identical to default, |
| 25 | * but useful to set in a VMA when you have a non default |
| 26 | * process policy. |
| 27 | * default Allocate on the local node first, or when on a VMA |
| 28 | * use the process policy. This is what Linux always did |
| 29 | * in a NUMA aware kernel and still does by, ahem, default. |
| 30 | * |
| 31 | * The process policy is applied for most non interrupt memory allocations |
| 32 | * in that process' context. Interrupts ignore the policies and always |
| 33 | * try to allocate on the local CPU. The VMA policy is only applied for memory |
| 34 | * allocations for a VMA in the VM. |
| 35 | * |
| 36 | * Currently there are a few corner cases in swapping where the policy |
| 37 | * is not applied, but the majority should be handled. When process policy |
| 38 | * is used it is not remembered over swap outs/swap ins. |
| 39 | * |
| 40 | * Only the highest zone in the zone hierarchy gets policied. Allocations |
| 41 | * requesting a lower zone just use default policy. This implies that |
| 42 | * on systems with highmem kernel lowmem allocation don't get policied. |
| 43 | * Same with GFP_DMA allocations. |
| 44 | * |
| 45 | * For shmfs/tmpfs/hugetlbfs shared memory the policy is shared between |
| 46 | * all users and remembered even when nobody has memory mapped. |
| 47 | */ |
| 48 | |
| 49 | /* Notebook: |
| 50 | fix mmap readahead to honour policy and enable policy for any page cache |
| 51 | object |
| 52 | statistics for bigpages |
| 53 | global policy for page cache? currently it uses process policy. Requires |
| 54 | first item above. |
| 55 | handle mremap for shared memory (currently ignored for the policy) |
| 56 | grows down? |
| 57 | make bind policy root only? It can trigger oom much faster and the |
| 58 | kernel is not always grateful with that. |
| 59 | could replace all the switch()es with a mempolicy_ops structure. |
| 60 | */ |
| 61 | |
| 62 | #include <linux/mempolicy.h> |
| 63 | #include <linux/mm.h> |
| 64 | #include <linux/highmem.h> |
| 65 | #include <linux/hugetlb.h> |
| 66 | #include <linux/kernel.h> |
| 67 | #include <linux/sched.h> |
| 68 | #include <linux/mm.h> |
| 69 | #include <linux/nodemask.h> |
| 70 | #include <linux/cpuset.h> |
| 71 | #include <linux/gfp.h> |
| 72 | #include <linux/slab.h> |
| 73 | #include <linux/string.h> |
| 74 | #include <linux/module.h> |
| 75 | #include <linux/interrupt.h> |
| 76 | #include <linux/init.h> |
| 77 | #include <linux/compat.h> |
| 78 | #include <linux/mempolicy.h> |
| 79 | #include <asm/tlbflush.h> |
| 80 | #include <asm/uaccess.h> |
| 81 | |
| 82 | static kmem_cache_t *policy_cache; |
| 83 | static kmem_cache_t *sn_cache; |
| 84 | |
| 85 | #define PDprintk(fmt...) |
| 86 | |
| 87 | /* Highest zone. An specific allocation for a zone below that is not |
| 88 | policied. */ |
| 89 | static int policy_zone; |
| 90 | |
| 91 | static struct mempolicy default_policy = { |
| 92 | .refcnt = ATOMIC_INIT(1), /* never free it */ |
| 93 | .policy = MPOL_DEFAULT, |
| 94 | }; |
| 95 | |
| 96 | /* Check if all specified nodes are online */ |
| 97 | static int nodes_online(unsigned long *nodes) |
| 98 | { |
| 99 | DECLARE_BITMAP(online2, MAX_NUMNODES); |
| 100 | |
| 101 | bitmap_copy(online2, nodes_addr(node_online_map), MAX_NUMNODES); |
| 102 | if (bitmap_empty(online2, MAX_NUMNODES)) |
| 103 | set_bit(0, online2); |
| 104 | if (!bitmap_subset(nodes, online2, MAX_NUMNODES)) |
| 105 | return -EINVAL; |
| 106 | return 0; |
| 107 | } |
| 108 | |
| 109 | /* Do sanity checking on a policy */ |
| 110 | static int mpol_check_policy(int mode, unsigned long *nodes) |
| 111 | { |
| 112 | int empty = bitmap_empty(nodes, MAX_NUMNODES); |
| 113 | |
| 114 | switch (mode) { |
| 115 | case MPOL_DEFAULT: |
| 116 | if (!empty) |
| 117 | return -EINVAL; |
| 118 | break; |
| 119 | case MPOL_BIND: |
| 120 | case MPOL_INTERLEAVE: |
| 121 | /* Preferred will only use the first bit, but allow |
| 122 | more for now. */ |
| 123 | if (empty) |
| 124 | return -EINVAL; |
| 125 | break; |
| 126 | } |
| 127 | return nodes_online(nodes); |
| 128 | } |
| 129 | |
| 130 | /* Copy a node mask from user space. */ |
| 131 | static int get_nodes(unsigned long *nodes, unsigned long __user *nmask, |
| 132 | unsigned long maxnode, int mode) |
| 133 | { |
| 134 | unsigned long k; |
| 135 | unsigned long nlongs; |
| 136 | unsigned long endmask; |
| 137 | |
| 138 | --maxnode; |
| 139 | bitmap_zero(nodes, MAX_NUMNODES); |
| 140 | if (maxnode == 0 || !nmask) |
| 141 | return 0; |
| 142 | |
| 143 | nlongs = BITS_TO_LONGS(maxnode); |
| 144 | if ((maxnode % BITS_PER_LONG) == 0) |
| 145 | endmask = ~0UL; |
| 146 | else |
| 147 | endmask = (1UL << (maxnode % BITS_PER_LONG)) - 1; |
| 148 | |
| 149 | /* When the user specified more nodes than supported just check |
| 150 | if the non supported part is all zero. */ |
| 151 | if (nlongs > BITS_TO_LONGS(MAX_NUMNODES)) { |
| 152 | if (nlongs > PAGE_SIZE/sizeof(long)) |
| 153 | return -EINVAL; |
| 154 | for (k = BITS_TO_LONGS(MAX_NUMNODES); k < nlongs; k++) { |
| 155 | unsigned long t; |
| 156 | if (get_user(t, nmask + k)) |
| 157 | return -EFAULT; |
| 158 | if (k == nlongs - 1) { |
| 159 | if (t & endmask) |
| 160 | return -EINVAL; |
| 161 | } else if (t) |
| 162 | return -EINVAL; |
| 163 | } |
| 164 | nlongs = BITS_TO_LONGS(MAX_NUMNODES); |
| 165 | endmask = ~0UL; |
| 166 | } |
| 167 | |
| 168 | if (copy_from_user(nodes, nmask, nlongs*sizeof(unsigned long))) |
| 169 | return -EFAULT; |
| 170 | nodes[nlongs-1] &= endmask; |
| 171 | /* Update current mems_allowed */ |
| 172 | cpuset_update_current_mems_allowed(); |
| 173 | /* Ignore nodes not set in current->mems_allowed */ |
| 174 | cpuset_restrict_to_mems_allowed(nodes); |
| 175 | return mpol_check_policy(mode, nodes); |
| 176 | } |
| 177 | |
| 178 | /* Generate a custom zonelist for the BIND policy. */ |
| 179 | static struct zonelist *bind_zonelist(unsigned long *nodes) |
| 180 | { |
| 181 | struct zonelist *zl; |
| 182 | int num, max, nd; |
| 183 | |
| 184 | max = 1 + MAX_NR_ZONES * bitmap_weight(nodes, MAX_NUMNODES); |
| 185 | zl = kmalloc(sizeof(void *) * max, GFP_KERNEL); |
| 186 | if (!zl) |
| 187 | return NULL; |
| 188 | num = 0; |
| 189 | for (nd = find_first_bit(nodes, MAX_NUMNODES); |
| 190 | nd < MAX_NUMNODES; |
| 191 | nd = find_next_bit(nodes, MAX_NUMNODES, 1+nd)) { |
| 192 | int k; |
| 193 | for (k = MAX_NR_ZONES-1; k >= 0; k--) { |
| 194 | struct zone *z = &NODE_DATA(nd)->node_zones[k]; |
| 195 | if (!z->present_pages) |
| 196 | continue; |
| 197 | zl->zones[num++] = z; |
| 198 | if (k > policy_zone) |
| 199 | policy_zone = k; |
| 200 | } |
| 201 | } |
| 202 | BUG_ON(num >= max); |
| 203 | zl->zones[num] = NULL; |
| 204 | return zl; |
| 205 | } |
| 206 | |
| 207 | /* Create a new policy */ |
| 208 | static struct mempolicy *mpol_new(int mode, unsigned long *nodes) |
| 209 | { |
| 210 | struct mempolicy *policy; |
| 211 | |
| 212 | PDprintk("setting mode %d nodes[0] %lx\n", mode, nodes[0]); |
| 213 | if (mode == MPOL_DEFAULT) |
| 214 | return NULL; |
| 215 | policy = kmem_cache_alloc(policy_cache, GFP_KERNEL); |
| 216 | if (!policy) |
| 217 | return ERR_PTR(-ENOMEM); |
| 218 | atomic_set(&policy->refcnt, 1); |
| 219 | switch (mode) { |
| 220 | case MPOL_INTERLEAVE: |
| 221 | bitmap_copy(policy->v.nodes, nodes, MAX_NUMNODES); |
| 222 | break; |
| 223 | case MPOL_PREFERRED: |
| 224 | policy->v.preferred_node = find_first_bit(nodes, MAX_NUMNODES); |
| 225 | if (policy->v.preferred_node >= MAX_NUMNODES) |
| 226 | policy->v.preferred_node = -1; |
| 227 | break; |
| 228 | case MPOL_BIND: |
| 229 | policy->v.zonelist = bind_zonelist(nodes); |
| 230 | if (policy->v.zonelist == NULL) { |
| 231 | kmem_cache_free(policy_cache, policy); |
| 232 | return ERR_PTR(-ENOMEM); |
| 233 | } |
| 234 | break; |
| 235 | } |
| 236 | policy->policy = mode; |
| 237 | return policy; |
| 238 | } |
| 239 | |
| 240 | /* Ensure all existing pages follow the policy. */ |
Hugh Dickins | 91612e0 | 2005-06-21 17:15:07 -0700 | [diff] [blame^] | 241 | static int check_pte_range(struct mm_struct *mm, pmd_t *pmd, |
| 242 | unsigned long addr, unsigned long end, unsigned long *nodes) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 243 | { |
Hugh Dickins | 91612e0 | 2005-06-21 17:15:07 -0700 | [diff] [blame^] | 244 | pte_t *orig_pte; |
| 245 | pte_t *pte; |
Hugh Dickins | 941150a | 2005-06-21 17:15:06 -0700 | [diff] [blame] | 246 | |
| 247 | spin_lock(&mm->page_table_lock); |
Hugh Dickins | 91612e0 | 2005-06-21 17:15:07 -0700 | [diff] [blame^] | 248 | orig_pte = pte = pte_offset_map(pmd, addr); |
| 249 | do { |
| 250 | unsigned long pfn; |
| 251 | unsigned int nid; |
| 252 | |
| 253 | if (!pte_present(*pte)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 254 | continue; |
Hugh Dickins | 91612e0 | 2005-06-21 17:15:07 -0700 | [diff] [blame^] | 255 | pfn = pte_pfn(*pte); |
| 256 | if (!pfn_valid(pfn)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 257 | continue; |
Hugh Dickins | 91612e0 | 2005-06-21 17:15:07 -0700 | [diff] [blame^] | 258 | nid = pfn_to_nid(pfn); |
| 259 | if (!test_bit(nid, nodes)) |
| 260 | break; |
| 261 | } while (pte++, addr += PAGE_SIZE, addr != end); |
| 262 | pte_unmap(orig_pte); |
Hugh Dickins | 941150a | 2005-06-21 17:15:06 -0700 | [diff] [blame] | 263 | spin_unlock(&mm->page_table_lock); |
Hugh Dickins | 91612e0 | 2005-06-21 17:15:07 -0700 | [diff] [blame^] | 264 | return addr != end; |
| 265 | } |
| 266 | |
| 267 | static inline int check_pmd_range(struct mm_struct *mm, pud_t *pud, |
| 268 | unsigned long addr, unsigned long end, unsigned long *nodes) |
| 269 | { |
| 270 | pmd_t *pmd; |
| 271 | unsigned long next; |
| 272 | |
| 273 | pmd = pmd_offset(pud, addr); |
| 274 | do { |
| 275 | next = pmd_addr_end(addr, end); |
| 276 | if (pmd_none_or_clear_bad(pmd)) |
| 277 | continue; |
| 278 | if (check_pte_range(mm, pmd, addr, next, nodes)) |
| 279 | return -EIO; |
| 280 | } while (pmd++, addr = next, addr != end); |
| 281 | return 0; |
| 282 | } |
| 283 | |
| 284 | static inline int check_pud_range(struct mm_struct *mm, pgd_t *pgd, |
| 285 | unsigned long addr, unsigned long end, unsigned long *nodes) |
| 286 | { |
| 287 | pud_t *pud; |
| 288 | unsigned long next; |
| 289 | |
| 290 | pud = pud_offset(pgd, addr); |
| 291 | do { |
| 292 | next = pud_addr_end(addr, end); |
| 293 | if (pud_none_or_clear_bad(pud)) |
| 294 | continue; |
| 295 | if (check_pmd_range(mm, pud, addr, next, nodes)) |
| 296 | return -EIO; |
| 297 | } while (pud++, addr = next, addr != end); |
| 298 | return 0; |
| 299 | } |
| 300 | |
| 301 | static inline int check_pgd_range(struct mm_struct *mm, |
| 302 | unsigned long addr, unsigned long end, unsigned long *nodes) |
| 303 | { |
| 304 | pgd_t *pgd; |
| 305 | unsigned long next; |
| 306 | |
| 307 | pgd = pgd_offset(mm, addr); |
| 308 | do { |
| 309 | next = pgd_addr_end(addr, end); |
| 310 | if (pgd_none_or_clear_bad(pgd)) |
| 311 | continue; |
| 312 | if (check_pud_range(mm, pgd, addr, next, nodes)) |
| 313 | return -EIO; |
| 314 | } while (pgd++, addr = next, addr != end); |
| 315 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 316 | } |
| 317 | |
| 318 | /* Step 1: check the range */ |
| 319 | static struct vm_area_struct * |
| 320 | check_range(struct mm_struct *mm, unsigned long start, unsigned long end, |
| 321 | unsigned long *nodes, unsigned long flags) |
| 322 | { |
| 323 | int err; |
| 324 | struct vm_area_struct *first, *vma, *prev; |
| 325 | |
| 326 | first = find_vma(mm, start); |
| 327 | if (!first) |
| 328 | return ERR_PTR(-EFAULT); |
| 329 | prev = NULL; |
| 330 | for (vma = first; vma && vma->vm_start < end; vma = vma->vm_next) { |
| 331 | if (!vma->vm_next && vma->vm_end < end) |
| 332 | return ERR_PTR(-EFAULT); |
| 333 | if (prev && prev->vm_end < vma->vm_start) |
| 334 | return ERR_PTR(-EFAULT); |
| 335 | if ((flags & MPOL_MF_STRICT) && !is_vm_hugetlb_page(vma)) { |
Hugh Dickins | 91612e0 | 2005-06-21 17:15:07 -0700 | [diff] [blame^] | 336 | err = check_pgd_range(vma->vm_mm, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 337 | vma->vm_start, vma->vm_end, nodes); |
| 338 | if (err) { |
| 339 | first = ERR_PTR(err); |
| 340 | break; |
| 341 | } |
| 342 | } |
| 343 | prev = vma; |
| 344 | } |
| 345 | return first; |
| 346 | } |
| 347 | |
| 348 | /* Apply policy to a single VMA */ |
| 349 | static int policy_vma(struct vm_area_struct *vma, struct mempolicy *new) |
| 350 | { |
| 351 | int err = 0; |
| 352 | struct mempolicy *old = vma->vm_policy; |
| 353 | |
| 354 | PDprintk("vma %lx-%lx/%lx vm_ops %p vm_file %p set_policy %p\n", |
| 355 | vma->vm_start, vma->vm_end, vma->vm_pgoff, |
| 356 | vma->vm_ops, vma->vm_file, |
| 357 | vma->vm_ops ? vma->vm_ops->set_policy : NULL); |
| 358 | |
| 359 | if (vma->vm_ops && vma->vm_ops->set_policy) |
| 360 | err = vma->vm_ops->set_policy(vma, new); |
| 361 | if (!err) { |
| 362 | mpol_get(new); |
| 363 | vma->vm_policy = new; |
| 364 | mpol_free(old); |
| 365 | } |
| 366 | return err; |
| 367 | } |
| 368 | |
| 369 | /* Step 2: apply policy to a range and do splits. */ |
| 370 | static int mbind_range(struct vm_area_struct *vma, unsigned long start, |
| 371 | unsigned long end, struct mempolicy *new) |
| 372 | { |
| 373 | struct vm_area_struct *next; |
| 374 | int err; |
| 375 | |
| 376 | err = 0; |
| 377 | for (; vma && vma->vm_start < end; vma = next) { |
| 378 | next = vma->vm_next; |
| 379 | if (vma->vm_start < start) |
| 380 | err = split_vma(vma->vm_mm, vma, start, 1); |
| 381 | if (!err && vma->vm_end > end) |
| 382 | err = split_vma(vma->vm_mm, vma, end, 0); |
| 383 | if (!err) |
| 384 | err = policy_vma(vma, new); |
| 385 | if (err) |
| 386 | break; |
| 387 | } |
| 388 | return err; |
| 389 | } |
| 390 | |
| 391 | /* Change policy for a memory range */ |
| 392 | asmlinkage long sys_mbind(unsigned long start, unsigned long len, |
| 393 | unsigned long mode, |
| 394 | unsigned long __user *nmask, unsigned long maxnode, |
| 395 | unsigned flags) |
| 396 | { |
| 397 | struct vm_area_struct *vma; |
| 398 | struct mm_struct *mm = current->mm; |
| 399 | struct mempolicy *new; |
| 400 | unsigned long end; |
| 401 | DECLARE_BITMAP(nodes, MAX_NUMNODES); |
| 402 | int err; |
| 403 | |
| 404 | if ((flags & ~(unsigned long)(MPOL_MF_STRICT)) || mode > MPOL_MAX) |
| 405 | return -EINVAL; |
| 406 | if (start & ~PAGE_MASK) |
| 407 | return -EINVAL; |
| 408 | if (mode == MPOL_DEFAULT) |
| 409 | flags &= ~MPOL_MF_STRICT; |
| 410 | len = (len + PAGE_SIZE - 1) & PAGE_MASK; |
| 411 | end = start + len; |
| 412 | if (end < start) |
| 413 | return -EINVAL; |
| 414 | if (end == start) |
| 415 | return 0; |
| 416 | |
| 417 | err = get_nodes(nodes, nmask, maxnode, mode); |
| 418 | if (err) |
| 419 | return err; |
| 420 | |
| 421 | new = mpol_new(mode, nodes); |
| 422 | if (IS_ERR(new)) |
| 423 | return PTR_ERR(new); |
| 424 | |
| 425 | PDprintk("mbind %lx-%lx mode:%ld nodes:%lx\n",start,start+len, |
| 426 | mode,nodes[0]); |
| 427 | |
| 428 | down_write(&mm->mmap_sem); |
| 429 | vma = check_range(mm, start, end, nodes, flags); |
| 430 | err = PTR_ERR(vma); |
| 431 | if (!IS_ERR(vma)) |
| 432 | err = mbind_range(vma, start, end, new); |
| 433 | up_write(&mm->mmap_sem); |
| 434 | mpol_free(new); |
| 435 | return err; |
| 436 | } |
| 437 | |
| 438 | /* Set the process memory policy */ |
| 439 | asmlinkage long sys_set_mempolicy(int mode, unsigned long __user *nmask, |
| 440 | unsigned long maxnode) |
| 441 | { |
| 442 | int err; |
| 443 | struct mempolicy *new; |
| 444 | DECLARE_BITMAP(nodes, MAX_NUMNODES); |
| 445 | |
| 446 | if (mode > MPOL_MAX) |
| 447 | return -EINVAL; |
| 448 | err = get_nodes(nodes, nmask, maxnode, mode); |
| 449 | if (err) |
| 450 | return err; |
| 451 | new = mpol_new(mode, nodes); |
| 452 | if (IS_ERR(new)) |
| 453 | return PTR_ERR(new); |
| 454 | mpol_free(current->mempolicy); |
| 455 | current->mempolicy = new; |
| 456 | if (new && new->policy == MPOL_INTERLEAVE) |
| 457 | current->il_next = find_first_bit(new->v.nodes, MAX_NUMNODES); |
| 458 | return 0; |
| 459 | } |
| 460 | |
| 461 | /* Fill a zone bitmap for a policy */ |
| 462 | static void get_zonemask(struct mempolicy *p, unsigned long *nodes) |
| 463 | { |
| 464 | int i; |
| 465 | |
| 466 | bitmap_zero(nodes, MAX_NUMNODES); |
| 467 | switch (p->policy) { |
| 468 | case MPOL_BIND: |
| 469 | for (i = 0; p->v.zonelist->zones[i]; i++) |
| 470 | __set_bit(p->v.zonelist->zones[i]->zone_pgdat->node_id, nodes); |
| 471 | break; |
| 472 | case MPOL_DEFAULT: |
| 473 | break; |
| 474 | case MPOL_INTERLEAVE: |
| 475 | bitmap_copy(nodes, p->v.nodes, MAX_NUMNODES); |
| 476 | break; |
| 477 | case MPOL_PREFERRED: |
| 478 | /* or use current node instead of online map? */ |
| 479 | if (p->v.preferred_node < 0) |
| 480 | bitmap_copy(nodes, nodes_addr(node_online_map), MAX_NUMNODES); |
| 481 | else |
| 482 | __set_bit(p->v.preferred_node, nodes); |
| 483 | break; |
| 484 | default: |
| 485 | BUG(); |
| 486 | } |
| 487 | } |
| 488 | |
| 489 | static int lookup_node(struct mm_struct *mm, unsigned long addr) |
| 490 | { |
| 491 | struct page *p; |
| 492 | int err; |
| 493 | |
| 494 | err = get_user_pages(current, mm, addr & PAGE_MASK, 1, 0, 0, &p, NULL); |
| 495 | if (err >= 0) { |
| 496 | err = page_to_nid(p); |
| 497 | put_page(p); |
| 498 | } |
| 499 | return err; |
| 500 | } |
| 501 | |
| 502 | /* Copy a kernel node mask to user space */ |
| 503 | static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode, |
| 504 | void *nodes, unsigned nbytes) |
| 505 | { |
| 506 | unsigned long copy = ALIGN(maxnode-1, 64) / 8; |
| 507 | |
| 508 | if (copy > nbytes) { |
| 509 | if (copy > PAGE_SIZE) |
| 510 | return -EINVAL; |
| 511 | if (clear_user((char __user *)mask + nbytes, copy - nbytes)) |
| 512 | return -EFAULT; |
| 513 | copy = nbytes; |
| 514 | } |
| 515 | return copy_to_user(mask, nodes, copy) ? -EFAULT : 0; |
| 516 | } |
| 517 | |
| 518 | /* Retrieve NUMA policy */ |
| 519 | asmlinkage long sys_get_mempolicy(int __user *policy, |
| 520 | unsigned long __user *nmask, |
| 521 | unsigned long maxnode, |
| 522 | unsigned long addr, unsigned long flags) |
| 523 | { |
| 524 | int err, pval; |
| 525 | struct mm_struct *mm = current->mm; |
| 526 | struct vm_area_struct *vma = NULL; |
| 527 | struct mempolicy *pol = current->mempolicy; |
| 528 | |
| 529 | if (flags & ~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR)) |
| 530 | return -EINVAL; |
| 531 | if (nmask != NULL && maxnode < MAX_NUMNODES) |
| 532 | return -EINVAL; |
| 533 | if (flags & MPOL_F_ADDR) { |
| 534 | down_read(&mm->mmap_sem); |
| 535 | vma = find_vma_intersection(mm, addr, addr+1); |
| 536 | if (!vma) { |
| 537 | up_read(&mm->mmap_sem); |
| 538 | return -EFAULT; |
| 539 | } |
| 540 | if (vma->vm_ops && vma->vm_ops->get_policy) |
| 541 | pol = vma->vm_ops->get_policy(vma, addr); |
| 542 | else |
| 543 | pol = vma->vm_policy; |
| 544 | } else if (addr) |
| 545 | return -EINVAL; |
| 546 | |
| 547 | if (!pol) |
| 548 | pol = &default_policy; |
| 549 | |
| 550 | if (flags & MPOL_F_NODE) { |
| 551 | if (flags & MPOL_F_ADDR) { |
| 552 | err = lookup_node(mm, addr); |
| 553 | if (err < 0) |
| 554 | goto out; |
| 555 | pval = err; |
| 556 | } else if (pol == current->mempolicy && |
| 557 | pol->policy == MPOL_INTERLEAVE) { |
| 558 | pval = current->il_next; |
| 559 | } else { |
| 560 | err = -EINVAL; |
| 561 | goto out; |
| 562 | } |
| 563 | } else |
| 564 | pval = pol->policy; |
| 565 | |
| 566 | if (vma) { |
| 567 | up_read(¤t->mm->mmap_sem); |
| 568 | vma = NULL; |
| 569 | } |
| 570 | |
| 571 | if (policy && put_user(pval, policy)) |
| 572 | return -EFAULT; |
| 573 | |
| 574 | err = 0; |
| 575 | if (nmask) { |
| 576 | DECLARE_BITMAP(nodes, MAX_NUMNODES); |
| 577 | get_zonemask(pol, nodes); |
| 578 | err = copy_nodes_to_user(nmask, maxnode, nodes, sizeof(nodes)); |
| 579 | } |
| 580 | |
| 581 | out: |
| 582 | if (vma) |
| 583 | up_read(¤t->mm->mmap_sem); |
| 584 | return err; |
| 585 | } |
| 586 | |
| 587 | #ifdef CONFIG_COMPAT |
| 588 | |
| 589 | asmlinkage long compat_sys_get_mempolicy(int __user *policy, |
| 590 | compat_ulong_t __user *nmask, |
| 591 | compat_ulong_t maxnode, |
| 592 | compat_ulong_t addr, compat_ulong_t flags) |
| 593 | { |
| 594 | long err; |
| 595 | unsigned long __user *nm = NULL; |
| 596 | unsigned long nr_bits, alloc_size; |
| 597 | DECLARE_BITMAP(bm, MAX_NUMNODES); |
| 598 | |
| 599 | nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES); |
| 600 | alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8; |
| 601 | |
| 602 | if (nmask) |
| 603 | nm = compat_alloc_user_space(alloc_size); |
| 604 | |
| 605 | err = sys_get_mempolicy(policy, nm, nr_bits+1, addr, flags); |
| 606 | |
| 607 | if (!err && nmask) { |
| 608 | err = copy_from_user(bm, nm, alloc_size); |
| 609 | /* ensure entire bitmap is zeroed */ |
| 610 | err |= clear_user(nmask, ALIGN(maxnode-1, 8) / 8); |
| 611 | err |= compat_put_bitmap(nmask, bm, nr_bits); |
| 612 | } |
| 613 | |
| 614 | return err; |
| 615 | } |
| 616 | |
| 617 | asmlinkage long compat_sys_set_mempolicy(int mode, compat_ulong_t __user *nmask, |
| 618 | compat_ulong_t maxnode) |
| 619 | { |
| 620 | long err = 0; |
| 621 | unsigned long __user *nm = NULL; |
| 622 | unsigned long nr_bits, alloc_size; |
| 623 | DECLARE_BITMAP(bm, MAX_NUMNODES); |
| 624 | |
| 625 | nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES); |
| 626 | alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8; |
| 627 | |
| 628 | if (nmask) { |
| 629 | err = compat_get_bitmap(bm, nmask, nr_bits); |
| 630 | nm = compat_alloc_user_space(alloc_size); |
| 631 | err |= copy_to_user(nm, bm, alloc_size); |
| 632 | } |
| 633 | |
| 634 | if (err) |
| 635 | return -EFAULT; |
| 636 | |
| 637 | return sys_set_mempolicy(mode, nm, nr_bits+1); |
| 638 | } |
| 639 | |
| 640 | asmlinkage long compat_sys_mbind(compat_ulong_t start, compat_ulong_t len, |
| 641 | compat_ulong_t mode, compat_ulong_t __user *nmask, |
| 642 | compat_ulong_t maxnode, compat_ulong_t flags) |
| 643 | { |
| 644 | long err = 0; |
| 645 | unsigned long __user *nm = NULL; |
| 646 | unsigned long nr_bits, alloc_size; |
| 647 | DECLARE_BITMAP(bm, MAX_NUMNODES); |
| 648 | |
| 649 | nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES); |
| 650 | alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8; |
| 651 | |
| 652 | if (nmask) { |
| 653 | err = compat_get_bitmap(bm, nmask, nr_bits); |
| 654 | nm = compat_alloc_user_space(alloc_size); |
| 655 | err |= copy_to_user(nm, bm, alloc_size); |
| 656 | } |
| 657 | |
| 658 | if (err) |
| 659 | return -EFAULT; |
| 660 | |
| 661 | return sys_mbind(start, len, mode, nm, nr_bits+1, flags); |
| 662 | } |
| 663 | |
| 664 | #endif |
| 665 | |
| 666 | /* Return effective policy for a VMA */ |
| 667 | static struct mempolicy * |
| 668 | get_vma_policy(struct vm_area_struct *vma, unsigned long addr) |
| 669 | { |
| 670 | struct mempolicy *pol = current->mempolicy; |
| 671 | |
| 672 | if (vma) { |
| 673 | if (vma->vm_ops && vma->vm_ops->get_policy) |
| 674 | pol = vma->vm_ops->get_policy(vma, addr); |
| 675 | else if (vma->vm_policy && |
| 676 | vma->vm_policy->policy != MPOL_DEFAULT) |
| 677 | pol = vma->vm_policy; |
| 678 | } |
| 679 | if (!pol) |
| 680 | pol = &default_policy; |
| 681 | return pol; |
| 682 | } |
| 683 | |
| 684 | /* Return a zonelist representing a mempolicy */ |
| 685 | static struct zonelist *zonelist_policy(unsigned int __nocast gfp, struct mempolicy *policy) |
| 686 | { |
| 687 | int nd; |
| 688 | |
| 689 | switch (policy->policy) { |
| 690 | case MPOL_PREFERRED: |
| 691 | nd = policy->v.preferred_node; |
| 692 | if (nd < 0) |
| 693 | nd = numa_node_id(); |
| 694 | break; |
| 695 | case MPOL_BIND: |
| 696 | /* Lower zones don't get a policy applied */ |
| 697 | /* Careful: current->mems_allowed might have moved */ |
Al Viro | 0142496 | 2005-04-24 12:28:34 -0700 | [diff] [blame] | 698 | if ((gfp & GFP_ZONEMASK) >= policy_zone) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 699 | if (cpuset_zonelist_valid_mems_allowed(policy->v.zonelist)) |
| 700 | return policy->v.zonelist; |
| 701 | /*FALL THROUGH*/ |
| 702 | case MPOL_INTERLEAVE: /* should not happen */ |
| 703 | case MPOL_DEFAULT: |
| 704 | nd = numa_node_id(); |
| 705 | break; |
| 706 | default: |
| 707 | nd = 0; |
| 708 | BUG(); |
| 709 | } |
| 710 | return NODE_DATA(nd)->node_zonelists + (gfp & GFP_ZONEMASK); |
| 711 | } |
| 712 | |
| 713 | /* Do dynamic interleaving for a process */ |
| 714 | static unsigned interleave_nodes(struct mempolicy *policy) |
| 715 | { |
| 716 | unsigned nid, next; |
| 717 | struct task_struct *me = current; |
| 718 | |
| 719 | nid = me->il_next; |
| 720 | BUG_ON(nid >= MAX_NUMNODES); |
| 721 | next = find_next_bit(policy->v.nodes, MAX_NUMNODES, 1+nid); |
| 722 | if (next >= MAX_NUMNODES) |
| 723 | next = find_first_bit(policy->v.nodes, MAX_NUMNODES); |
| 724 | me->il_next = next; |
| 725 | return nid; |
| 726 | } |
| 727 | |
| 728 | /* Do static interleaving for a VMA with known offset. */ |
| 729 | static unsigned offset_il_node(struct mempolicy *pol, |
| 730 | struct vm_area_struct *vma, unsigned long off) |
| 731 | { |
| 732 | unsigned nnodes = bitmap_weight(pol->v.nodes, MAX_NUMNODES); |
| 733 | unsigned target = (unsigned)off % nnodes; |
| 734 | int c; |
| 735 | int nid = -1; |
| 736 | |
| 737 | c = 0; |
| 738 | do { |
| 739 | nid = find_next_bit(pol->v.nodes, MAX_NUMNODES, nid+1); |
| 740 | c++; |
| 741 | } while (c <= target); |
| 742 | BUG_ON(nid >= MAX_NUMNODES); |
| 743 | BUG_ON(!test_bit(nid, pol->v.nodes)); |
| 744 | return nid; |
| 745 | } |
| 746 | |
| 747 | /* Allocate a page in interleaved policy. |
| 748 | Own path because it needs to do special accounting. */ |
| 749 | static struct page *alloc_page_interleave(unsigned int __nocast gfp, unsigned order, unsigned nid) |
| 750 | { |
| 751 | struct zonelist *zl; |
| 752 | struct page *page; |
| 753 | |
| 754 | BUG_ON(!node_online(nid)); |
| 755 | zl = NODE_DATA(nid)->node_zonelists + (gfp & GFP_ZONEMASK); |
| 756 | page = __alloc_pages(gfp, order, zl); |
| 757 | if (page && page_zone(page) == zl->zones[0]) { |
Christoph Lameter | e7c8d5c | 2005-06-21 17:14:47 -0700 | [diff] [blame] | 758 | zone_pcp(zl->zones[0],get_cpu())->interleave_hit++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 759 | put_cpu(); |
| 760 | } |
| 761 | return page; |
| 762 | } |
| 763 | |
| 764 | /** |
| 765 | * alloc_page_vma - Allocate a page for a VMA. |
| 766 | * |
| 767 | * @gfp: |
| 768 | * %GFP_USER user allocation. |
| 769 | * %GFP_KERNEL kernel allocations, |
| 770 | * %GFP_HIGHMEM highmem/user allocations, |
| 771 | * %GFP_FS allocation should not call back into a file system. |
| 772 | * %GFP_ATOMIC don't sleep. |
| 773 | * |
| 774 | * @vma: Pointer to VMA or NULL if not available. |
| 775 | * @addr: Virtual Address of the allocation. Must be inside the VMA. |
| 776 | * |
| 777 | * This function allocates a page from the kernel page pool and applies |
| 778 | * a NUMA policy associated with the VMA or the current process. |
| 779 | * When VMA is not NULL caller must hold down_read on the mmap_sem of the |
| 780 | * mm_struct of the VMA to prevent it from going away. Should be used for |
| 781 | * all allocations for pages that will be mapped into |
| 782 | * user space. Returns NULL when no page can be allocated. |
| 783 | * |
| 784 | * Should be called with the mm_sem of the vma hold. |
| 785 | */ |
| 786 | struct page * |
| 787 | alloc_page_vma(unsigned int __nocast gfp, struct vm_area_struct *vma, unsigned long addr) |
| 788 | { |
| 789 | struct mempolicy *pol = get_vma_policy(vma, addr); |
| 790 | |
| 791 | cpuset_update_current_mems_allowed(); |
| 792 | |
| 793 | if (unlikely(pol->policy == MPOL_INTERLEAVE)) { |
| 794 | unsigned nid; |
| 795 | if (vma) { |
| 796 | unsigned long off; |
| 797 | BUG_ON(addr >= vma->vm_end); |
| 798 | BUG_ON(addr < vma->vm_start); |
| 799 | off = vma->vm_pgoff; |
| 800 | off += (addr - vma->vm_start) >> PAGE_SHIFT; |
| 801 | nid = offset_il_node(pol, vma, off); |
| 802 | } else { |
| 803 | /* fall back to process interleaving */ |
| 804 | nid = interleave_nodes(pol); |
| 805 | } |
| 806 | return alloc_page_interleave(gfp, 0, nid); |
| 807 | } |
| 808 | return __alloc_pages(gfp, 0, zonelist_policy(gfp, pol)); |
| 809 | } |
| 810 | |
| 811 | /** |
| 812 | * alloc_pages_current - Allocate pages. |
| 813 | * |
| 814 | * @gfp: |
| 815 | * %GFP_USER user allocation, |
| 816 | * %GFP_KERNEL kernel allocation, |
| 817 | * %GFP_HIGHMEM highmem allocation, |
| 818 | * %GFP_FS don't call back into a file system. |
| 819 | * %GFP_ATOMIC don't sleep. |
| 820 | * @order: Power of two of allocation size in pages. 0 is a single page. |
| 821 | * |
| 822 | * Allocate a page from the kernel page pool. When not in |
| 823 | * interrupt context and apply the current process NUMA policy. |
| 824 | * Returns NULL when no page can be allocated. |
| 825 | * |
| 826 | * Don't call cpuset_update_current_mems_allowed() unless |
| 827 | * 1) it's ok to take cpuset_sem (can WAIT), and |
| 828 | * 2) allocating for current task (not interrupt). |
| 829 | */ |
| 830 | struct page *alloc_pages_current(unsigned int __nocast gfp, unsigned order) |
| 831 | { |
| 832 | struct mempolicy *pol = current->mempolicy; |
| 833 | |
| 834 | if ((gfp & __GFP_WAIT) && !in_interrupt()) |
| 835 | cpuset_update_current_mems_allowed(); |
| 836 | if (!pol || in_interrupt()) |
| 837 | pol = &default_policy; |
| 838 | if (pol->policy == MPOL_INTERLEAVE) |
| 839 | return alloc_page_interleave(gfp, order, interleave_nodes(pol)); |
| 840 | return __alloc_pages(gfp, order, zonelist_policy(gfp, pol)); |
| 841 | } |
| 842 | EXPORT_SYMBOL(alloc_pages_current); |
| 843 | |
| 844 | /* Slow path of a mempolicy copy */ |
| 845 | struct mempolicy *__mpol_copy(struct mempolicy *old) |
| 846 | { |
| 847 | struct mempolicy *new = kmem_cache_alloc(policy_cache, GFP_KERNEL); |
| 848 | |
| 849 | if (!new) |
| 850 | return ERR_PTR(-ENOMEM); |
| 851 | *new = *old; |
| 852 | atomic_set(&new->refcnt, 1); |
| 853 | if (new->policy == MPOL_BIND) { |
| 854 | int sz = ksize(old->v.zonelist); |
| 855 | new->v.zonelist = kmalloc(sz, SLAB_KERNEL); |
| 856 | if (!new->v.zonelist) { |
| 857 | kmem_cache_free(policy_cache, new); |
| 858 | return ERR_PTR(-ENOMEM); |
| 859 | } |
| 860 | memcpy(new->v.zonelist, old->v.zonelist, sz); |
| 861 | } |
| 862 | return new; |
| 863 | } |
| 864 | |
| 865 | /* Slow path of a mempolicy comparison */ |
| 866 | int __mpol_equal(struct mempolicy *a, struct mempolicy *b) |
| 867 | { |
| 868 | if (!a || !b) |
| 869 | return 0; |
| 870 | if (a->policy != b->policy) |
| 871 | return 0; |
| 872 | switch (a->policy) { |
| 873 | case MPOL_DEFAULT: |
| 874 | return 1; |
| 875 | case MPOL_INTERLEAVE: |
| 876 | return bitmap_equal(a->v.nodes, b->v.nodes, MAX_NUMNODES); |
| 877 | case MPOL_PREFERRED: |
| 878 | return a->v.preferred_node == b->v.preferred_node; |
| 879 | case MPOL_BIND: { |
| 880 | int i; |
| 881 | for (i = 0; a->v.zonelist->zones[i]; i++) |
| 882 | if (a->v.zonelist->zones[i] != b->v.zonelist->zones[i]) |
| 883 | return 0; |
| 884 | return b->v.zonelist->zones[i] == NULL; |
| 885 | } |
| 886 | default: |
| 887 | BUG(); |
| 888 | return 0; |
| 889 | } |
| 890 | } |
| 891 | |
| 892 | /* Slow path of a mpol destructor. */ |
| 893 | void __mpol_free(struct mempolicy *p) |
| 894 | { |
| 895 | if (!atomic_dec_and_test(&p->refcnt)) |
| 896 | return; |
| 897 | if (p->policy == MPOL_BIND) |
| 898 | kfree(p->v.zonelist); |
| 899 | p->policy = MPOL_DEFAULT; |
| 900 | kmem_cache_free(policy_cache, p); |
| 901 | } |
| 902 | |
| 903 | /* |
| 904 | * Hugetlb policy. Same as above, just works with node numbers instead of |
| 905 | * zonelists. |
| 906 | */ |
| 907 | |
| 908 | /* Find first node suitable for an allocation */ |
| 909 | int mpol_first_node(struct vm_area_struct *vma, unsigned long addr) |
| 910 | { |
| 911 | struct mempolicy *pol = get_vma_policy(vma, addr); |
| 912 | |
| 913 | switch (pol->policy) { |
| 914 | case MPOL_DEFAULT: |
| 915 | return numa_node_id(); |
| 916 | case MPOL_BIND: |
| 917 | return pol->v.zonelist->zones[0]->zone_pgdat->node_id; |
| 918 | case MPOL_INTERLEAVE: |
| 919 | return interleave_nodes(pol); |
| 920 | case MPOL_PREFERRED: |
| 921 | return pol->v.preferred_node >= 0 ? |
| 922 | pol->v.preferred_node : numa_node_id(); |
| 923 | } |
| 924 | BUG(); |
| 925 | return 0; |
| 926 | } |
| 927 | |
| 928 | /* Find secondary valid nodes for an allocation */ |
| 929 | int mpol_node_valid(int nid, struct vm_area_struct *vma, unsigned long addr) |
| 930 | { |
| 931 | struct mempolicy *pol = get_vma_policy(vma, addr); |
| 932 | |
| 933 | switch (pol->policy) { |
| 934 | case MPOL_PREFERRED: |
| 935 | case MPOL_DEFAULT: |
| 936 | case MPOL_INTERLEAVE: |
| 937 | return 1; |
| 938 | case MPOL_BIND: { |
| 939 | struct zone **z; |
| 940 | for (z = pol->v.zonelist->zones; *z; z++) |
| 941 | if ((*z)->zone_pgdat->node_id == nid) |
| 942 | return 1; |
| 943 | return 0; |
| 944 | } |
| 945 | default: |
| 946 | BUG(); |
| 947 | return 0; |
| 948 | } |
| 949 | } |
| 950 | |
| 951 | /* |
| 952 | * Shared memory backing store policy support. |
| 953 | * |
| 954 | * Remember policies even when nobody has shared memory mapped. |
| 955 | * The policies are kept in Red-Black tree linked from the inode. |
| 956 | * They are protected by the sp->lock spinlock, which should be held |
| 957 | * for any accesses to the tree. |
| 958 | */ |
| 959 | |
| 960 | /* lookup first element intersecting start-end */ |
| 961 | /* Caller holds sp->lock */ |
| 962 | static struct sp_node * |
| 963 | sp_lookup(struct shared_policy *sp, unsigned long start, unsigned long end) |
| 964 | { |
| 965 | struct rb_node *n = sp->root.rb_node; |
| 966 | |
| 967 | while (n) { |
| 968 | struct sp_node *p = rb_entry(n, struct sp_node, nd); |
| 969 | |
| 970 | if (start >= p->end) |
| 971 | n = n->rb_right; |
| 972 | else if (end <= p->start) |
| 973 | n = n->rb_left; |
| 974 | else |
| 975 | break; |
| 976 | } |
| 977 | if (!n) |
| 978 | return NULL; |
| 979 | for (;;) { |
| 980 | struct sp_node *w = NULL; |
| 981 | struct rb_node *prev = rb_prev(n); |
| 982 | if (!prev) |
| 983 | break; |
| 984 | w = rb_entry(prev, struct sp_node, nd); |
| 985 | if (w->end <= start) |
| 986 | break; |
| 987 | n = prev; |
| 988 | } |
| 989 | return rb_entry(n, struct sp_node, nd); |
| 990 | } |
| 991 | |
| 992 | /* Insert a new shared policy into the list. */ |
| 993 | /* Caller holds sp->lock */ |
| 994 | static void sp_insert(struct shared_policy *sp, struct sp_node *new) |
| 995 | { |
| 996 | struct rb_node **p = &sp->root.rb_node; |
| 997 | struct rb_node *parent = NULL; |
| 998 | struct sp_node *nd; |
| 999 | |
| 1000 | while (*p) { |
| 1001 | parent = *p; |
| 1002 | nd = rb_entry(parent, struct sp_node, nd); |
| 1003 | if (new->start < nd->start) |
| 1004 | p = &(*p)->rb_left; |
| 1005 | else if (new->end > nd->end) |
| 1006 | p = &(*p)->rb_right; |
| 1007 | else |
| 1008 | BUG(); |
| 1009 | } |
| 1010 | rb_link_node(&new->nd, parent, p); |
| 1011 | rb_insert_color(&new->nd, &sp->root); |
| 1012 | PDprintk("inserting %lx-%lx: %d\n", new->start, new->end, |
| 1013 | new->policy ? new->policy->policy : 0); |
| 1014 | } |
| 1015 | |
| 1016 | /* Find shared policy intersecting idx */ |
| 1017 | struct mempolicy * |
| 1018 | mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx) |
| 1019 | { |
| 1020 | struct mempolicy *pol = NULL; |
| 1021 | struct sp_node *sn; |
| 1022 | |
| 1023 | if (!sp->root.rb_node) |
| 1024 | return NULL; |
| 1025 | spin_lock(&sp->lock); |
| 1026 | sn = sp_lookup(sp, idx, idx+1); |
| 1027 | if (sn) { |
| 1028 | mpol_get(sn->policy); |
| 1029 | pol = sn->policy; |
| 1030 | } |
| 1031 | spin_unlock(&sp->lock); |
| 1032 | return pol; |
| 1033 | } |
| 1034 | |
| 1035 | static void sp_delete(struct shared_policy *sp, struct sp_node *n) |
| 1036 | { |
| 1037 | PDprintk("deleting %lx-l%x\n", n->start, n->end); |
| 1038 | rb_erase(&n->nd, &sp->root); |
| 1039 | mpol_free(n->policy); |
| 1040 | kmem_cache_free(sn_cache, n); |
| 1041 | } |
| 1042 | |
| 1043 | struct sp_node * |
| 1044 | sp_alloc(unsigned long start, unsigned long end, struct mempolicy *pol) |
| 1045 | { |
| 1046 | struct sp_node *n = kmem_cache_alloc(sn_cache, GFP_KERNEL); |
| 1047 | |
| 1048 | if (!n) |
| 1049 | return NULL; |
| 1050 | n->start = start; |
| 1051 | n->end = end; |
| 1052 | mpol_get(pol); |
| 1053 | n->policy = pol; |
| 1054 | return n; |
| 1055 | } |
| 1056 | |
| 1057 | /* Replace a policy range. */ |
| 1058 | static int shared_policy_replace(struct shared_policy *sp, unsigned long start, |
| 1059 | unsigned long end, struct sp_node *new) |
| 1060 | { |
| 1061 | struct sp_node *n, *new2 = NULL; |
| 1062 | |
| 1063 | restart: |
| 1064 | spin_lock(&sp->lock); |
| 1065 | n = sp_lookup(sp, start, end); |
| 1066 | /* Take care of old policies in the same range. */ |
| 1067 | while (n && n->start < end) { |
| 1068 | struct rb_node *next = rb_next(&n->nd); |
| 1069 | if (n->start >= start) { |
| 1070 | if (n->end <= end) |
| 1071 | sp_delete(sp, n); |
| 1072 | else |
| 1073 | n->start = end; |
| 1074 | } else { |
| 1075 | /* Old policy spanning whole new range. */ |
| 1076 | if (n->end > end) { |
| 1077 | if (!new2) { |
| 1078 | spin_unlock(&sp->lock); |
| 1079 | new2 = sp_alloc(end, n->end, n->policy); |
| 1080 | if (!new2) |
| 1081 | return -ENOMEM; |
| 1082 | goto restart; |
| 1083 | } |
| 1084 | n->end = start; |
| 1085 | sp_insert(sp, new2); |
| 1086 | new2 = NULL; |
| 1087 | break; |
| 1088 | } else |
| 1089 | n->end = start; |
| 1090 | } |
| 1091 | if (!next) |
| 1092 | break; |
| 1093 | n = rb_entry(next, struct sp_node, nd); |
| 1094 | } |
| 1095 | if (new) |
| 1096 | sp_insert(sp, new); |
| 1097 | spin_unlock(&sp->lock); |
| 1098 | if (new2) { |
| 1099 | mpol_free(new2->policy); |
| 1100 | kmem_cache_free(sn_cache, new2); |
| 1101 | } |
| 1102 | return 0; |
| 1103 | } |
| 1104 | |
| 1105 | int mpol_set_shared_policy(struct shared_policy *info, |
| 1106 | struct vm_area_struct *vma, struct mempolicy *npol) |
| 1107 | { |
| 1108 | int err; |
| 1109 | struct sp_node *new = NULL; |
| 1110 | unsigned long sz = vma_pages(vma); |
| 1111 | |
| 1112 | PDprintk("set_shared_policy %lx sz %lu %d %lx\n", |
| 1113 | vma->vm_pgoff, |
| 1114 | sz, npol? npol->policy : -1, |
| 1115 | npol ? npol->v.nodes[0] : -1); |
| 1116 | |
| 1117 | if (npol) { |
| 1118 | new = sp_alloc(vma->vm_pgoff, vma->vm_pgoff + sz, npol); |
| 1119 | if (!new) |
| 1120 | return -ENOMEM; |
| 1121 | } |
| 1122 | err = shared_policy_replace(info, vma->vm_pgoff, vma->vm_pgoff+sz, new); |
| 1123 | if (err && new) |
| 1124 | kmem_cache_free(sn_cache, new); |
| 1125 | return err; |
| 1126 | } |
| 1127 | |
| 1128 | /* Free a backing policy store on inode delete. */ |
| 1129 | void mpol_free_shared_policy(struct shared_policy *p) |
| 1130 | { |
| 1131 | struct sp_node *n; |
| 1132 | struct rb_node *next; |
| 1133 | |
| 1134 | if (!p->root.rb_node) |
| 1135 | return; |
| 1136 | spin_lock(&p->lock); |
| 1137 | next = rb_first(&p->root); |
| 1138 | while (next) { |
| 1139 | n = rb_entry(next, struct sp_node, nd); |
| 1140 | next = rb_next(&n->nd); |
| 1141 | mpol_free(n->policy); |
| 1142 | kmem_cache_free(sn_cache, n); |
| 1143 | } |
| 1144 | spin_unlock(&p->lock); |
| 1145 | p->root = RB_ROOT; |
| 1146 | } |
| 1147 | |
| 1148 | /* assumes fs == KERNEL_DS */ |
| 1149 | void __init numa_policy_init(void) |
| 1150 | { |
| 1151 | policy_cache = kmem_cache_create("numa_policy", |
| 1152 | sizeof(struct mempolicy), |
| 1153 | 0, SLAB_PANIC, NULL, NULL); |
| 1154 | |
| 1155 | sn_cache = kmem_cache_create("shared_policy_node", |
| 1156 | sizeof(struct sp_node), |
| 1157 | 0, SLAB_PANIC, NULL, NULL); |
| 1158 | |
| 1159 | /* Set interleaving policy for system init. This way not all |
| 1160 | the data structures allocated at system boot end up in node zero. */ |
| 1161 | |
| 1162 | if (sys_set_mempolicy(MPOL_INTERLEAVE, nodes_addr(node_online_map), |
| 1163 | MAX_NUMNODES) < 0) |
| 1164 | printk("numa_policy_init: interleaving failed\n"); |
| 1165 | } |
| 1166 | |
| 1167 | /* Reset policy of current process to default. |
| 1168 | * Assumes fs == KERNEL_DS */ |
| 1169 | void numa_default_policy(void) |
| 1170 | { |
| 1171 | sys_set_mempolicy(MPOL_DEFAULT, NULL, 0); |
| 1172 | } |