arch/powerpc/mm/slice.c

   1 /*
   2  * address space "slices" (meta-segments) support
   3  *
   4  * Copyright (C) 2007 Benjamin Herrenschmidt, IBM Corporation.
   5  *
   6  * Based on hugetlb implementation
   7  *
   8  * Copyright (C) 2003 David Gibson, IBM Corporation.
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  23  */
  24
  25 #undef DEBUG
  26
  27 #include <linux/kernel.h>
  28 #include <linux/mm.h>
  29 #include <linux/pagemap.h>
  30 #include <linux/err.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/module.h>
  33 #include <asm/mman.h>
  34 #include <asm/mmu.h>
  35 #include <asm/spu.h>
  36
  37 static DEFINE_SPINLOCK(slice_convert_lock);
  38
  39
  40 #ifdef DEBUG
  41 int _slice_debug = 1;
  42
  43 static void slice_print_mask(const char *label, struct slice_mask mask)
  44 {
  45         char    *p, buf[16 + 3 + 16 + 1];
  46         int     i;
  47
  48         if (!_slice_debug)
  49                 return;
  50         p = buf;
  51         for (i = 0; i < SLICE_NUM_LOW; i++)
  52                 *(p++) = (mask.low_slices & (1 << i)) ? '1' : '0';
  53         *(p++) = ' ';
  54         *(p++) = '-';
  55         *(p++) = ' ';
  56         for (i = 0; i < SLICE_NUM_HIGH; i++)
  57                 *(p++) = (mask.high_slices & (1 << i)) ? '1' : '0';
  58         *(p++) = 0;
  59
  60         printk(KERN_DEBUG "%s:%s\n", label, buf);
  61 }
  62
  63 #define slice_dbg(fmt...) do { if (_slice_debug) pr_debug(fmt); } while(0)
  64
  65 #else
  66
  67 static void slice_print_mask(const char *label, struct slice_mask mask) {}
  68 #define slice_dbg(fmt...)
  69
  70 #endif
  71
  72 static struct slice_mask slice_range_to_mask(unsigned long start,
  73                                              unsigned long len)
  74 {
  75         unsigned long end = start + len - 1;
  76         struct slice_mask ret = { 0, 0 };
  77
  78         if (start < SLICE_LOW_TOP) {
  79                 unsigned long mend = min(end, SLICE_LOW_TOP);
  80                 unsigned long mstart = min(start, SLICE_LOW_TOP);
  81
  82                 ret.low_slices = (1u << (GET_LOW_SLICE_INDEX(mend) + 1))
  83                         - (1u << GET_LOW_SLICE_INDEX(mstart));
  84         }
  85
  86         if ((start + len) > SLICE_LOW_TOP)
  87                 ret.high_slices = (1u << (GET_HIGH_SLICE_INDEX(end) + 1))
  88                         - (1u << GET_HIGH_SLICE_INDEX(start));
  89
  90         return ret;
  91 }
  92
  93 static int slice_area_is_free(struct mm_struct *mm, unsigned long addr,
  94                               unsigned long len)
  95 {
  96         struct vm_area_struct *vma;
  97
  98         if ((mm->task_size - len) < addr)
  99                 return 0;
 100         vma = find_vma(mm, addr);
 101         return (!vma || (addr + len) <= vma->vm_start);
 102 }
 103
 104 static int slice_low_has_vma(struct mm_struct *mm, unsigned long slice)
 105 {
 106         return !slice_area_is_free(mm, slice << SLICE_LOW_SHIFT,
 107                                    1ul << SLICE_LOW_SHIFT);
 108 }
 109
 110 static int slice_high_has_vma(struct mm_struct *mm, unsigned long slice)
 111 {
 112         unsigned long start = slice << SLICE_HIGH_SHIFT;
 113         unsigned long end = start + (1ul << SLICE_HIGH_SHIFT);
 114
 115         /* Hack, so that each addresses is controlled by exactly one
 116          * of the high or low area bitmaps, the first high area starts
 117          * at 4GB, not 0 */
 118         if (start == 0)
 119                 start = SLICE_LOW_TOP;
 120
 121         return !slice_area_is_free(mm, start, end - start);
 122 }
 123
 124 static struct slice_mask slice_mask_for_free(struct mm_struct *mm)
 125 {
 126         struct slice_mask ret = { 0, 0 };
 127         unsigned long i;
 128
 129         for (i = 0; i < SLICE_NUM_LOW; i++)
 130                 if (!slice_low_has_vma(mm, i))
 131                         ret.low_slices |= 1u << i;
 132
 133         if (mm->task_size <= SLICE_LOW_TOP)
 134                 return ret;
 135
 136         for (i = 0; i < SLICE_NUM_HIGH; i++)
 137                 if (!slice_high_has_vma(mm, i))
 138                         ret.high_slices |= 1u << i;
 139
 140         return ret;
 141 }
 142
 143 static struct slice_mask slice_mask_for_size(struct mm_struct *mm, int psize)
 144 {
 145         struct slice_mask ret = { 0, 0 };
 146         unsigned long i;
 147         u64 psizes;
 148
 149         psizes = mm->context.low_slices_psize;
 150         for (i = 0; i < SLICE_NUM_LOW; i++)
 151                 if (((psizes >> (i * 4)) & 0xf) == psize)
 152                         ret.low_slices |= 1u << i;
 153
 154         psizes = mm->context.high_slices_psize;
 155         for (i = 0; i < SLICE_NUM_HIGH; i++)
 156                 if (((psizes >> (i * 4)) & 0xf) == psize)
 157                         ret.high_slices |= 1u << i;
 158
 159         return ret;
 160 }
 161
 162 static int slice_check_fit(struct slice_mask mask, struct slice_mask available)
 163 {
 164         return (mask.low_slices & available.low_slices) == mask.low_slices &&
 165                 (mask.high_slices & available.high_slices) == mask.high_slices;
 166 }
 167
 168 static void slice_flush_segments(void *parm)
 169 {
 170         struct mm_struct *mm = parm;
 171         unsigned long flags;
 172
 173         if (mm != current->active_mm)
 174                 return;
 175
 176         /* update the paca copy of the context struct */
 177         get_paca()->context = current->active_mm->context;
 178
 179         local_irq_save(flags);
 180         slb_flush_and_rebolt();
 181         local_irq_restore(flags);
 182 }
 183
 184 static void slice_convert(struct mm_struct *mm, struct slice_mask mask, int psize)
 185 {
 186         /* Write the new slice psize bits */
 187         u64 lpsizes, hpsizes;
 188         unsigned long i, flags;
 189
 190         slice_dbg("slice_convert(mm=%p, psize=%d)\n", mm, psize);
 191         slice_print_mask(" mask", mask);
 192
 193         /* We need to use a spinlock here to protect against
 194          * concurrent 64k -> 4k demotion ...
 195          */
 196         spin_lock_irqsave(&slice_convert_lock, flags);
 197
 198         lpsizes = mm->context.low_slices_psize;
 199         for (i = 0; i < SLICE_NUM_LOW; i++)
 200                 if (mask.low_slices & (1u << i))
 201                         lpsizes = (lpsizes & ~(0xful << (i * 4))) |
 202                                 (((unsigned long)psize) << (i * 4));
 203
 204         hpsizes = mm->context.high_slices_psize;
 205         for (i = 0; i < SLICE_NUM_HIGH; i++)
 206                 if (mask.high_slices & (1u << i))
 207                         hpsizes = (hpsizes & ~(0xful << (i * 4))) |
 208                                 (((unsigned long)psize) << (i * 4));
 209
 210         mm->context.low_slices_psize = lpsizes;
 211         mm->context.high_slices_psize = hpsizes;
 212
 213         slice_dbg(" lsps=%lx, hsps=%lx\n",
 214                   mm->context.low_slices_psize,
 215                   mm->context.high_slices_psize);
 216
 217         spin_unlock_irqrestore(&slice_convert_lock, flags);
 218
 219 #ifdef CONFIG_SPU_BASE
 220         spu_flush_all_slbs(mm);
 221 #endif
 222 }
 223
 224 static unsigned long slice_find_area_bottomup(struct mm_struct *mm,
 225                                               unsigned long len,
 226                                               struct slice_mask available,
 227                                               int psize, int use_cache)
 228 {
 229         struct vm_area_struct *vma;
 230         unsigned long start_addr, addr;
 231         struct slice_mask mask;
 232         int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT);
 233
 234         if (use_cache) {
 235                 if (len <= mm->cached_hole_size) {
 236                         start_addr = addr = TASK_UNMAPPED_BASE;
 237                         mm->cached_hole_size = 0;
 238                 } else
 239                         start_addr = addr = mm->free_area_cache;
 240         } else
 241                 start_addr = addr = TASK_UNMAPPED_BASE;
 242
 243 full_search:
 244         for (;;) {
 245                 addr = _ALIGN_UP(addr, 1ul << pshift);
 246                 if ((TASK_SIZE - len) < addr)
 247                         break;
 248                 vma = find_vma(mm, addr);
 249                 BUG_ON(vma && (addr >= vma->vm_end));
 250
 251                 mask = slice_range_to_mask(addr, len);
 252                 if (!slice_check_fit(mask, available)) {
 253                         if (addr < SLICE_LOW_TOP)
 254                                 addr = _ALIGN_UP(addr + 1,  1ul << SLICE_LOW_SHIFT);
 255                         else
 256                                 addr = _ALIGN_UP(addr + 1,  1ul << SLICE_HIGH_SHIFT);
 257                         continue;
 258                 }
 259                 if (!vma || addr + len <= vma->vm_start) {
 260                         /*
 261                          * Remember the place where we stopped the search:
 262                          */
 263                         if (use_cache)
 264                                 mm->free_area_cache = addr + len;
 265                         return addr;
 266                 }
 267                 if (use_cache && (addr + mm->cached_hole_size) < vma->vm_start)
 268                         mm->cached_hole_size = vma->vm_start - addr;
 269                 addr = vma->vm_end;
 270         }
 271
 272         /* Make sure we didn't miss any holes */
 273         if (use_cache && start_addr != TASK_UNMAPPED_BASE) {
 274                 start_addr = addr = TASK_UNMAPPED_BASE;
 275                 mm->cached_hole_size = 0;
 276                 goto full_search;
 277         }
 278         return -ENOMEM;
 279 }
 280
 281 static unsigned long slice_find_area_topdown(struct mm_struct *mm,
 282                                              unsigned long len,
 283                                              struct slice_mask available,
 284                                              int psize, int use_cache)
 285 {
 286         struct vm_area_struct *vma;
 287         unsigned long addr;
 288         struct slice_mask mask;
 289         int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT);
 290
 291         /* check if free_area_cache is useful for us */
 292         if (use_cache) {
 293                 if (len <= mm->cached_hole_size) {
 294                         mm->cached_hole_size = 0;
 295                         mm->free_area_cache = mm->mmap_base;
 296                 }
 297
 298                 /* either no address requested or can't fit in requested
 299                  * address hole
 300                  */
 301                 addr = mm->free_area_cache;
 302
 303                 /* make sure it can fit in the remaining address space */
 304                 if (addr > len) {
 305                         addr = _ALIGN_DOWN(addr - len, 1ul << pshift);
 306                         mask = slice_range_to_mask(addr, len);
 307                         if (slice_check_fit(mask, available) &&
 308                             slice_area_is_free(mm, addr, len))
 309                                         /* remember the address as a hint for
 310                                          * next time
 311                                          */
 312                                         return (mm->free_area_cache = addr);
 313                 }
 314         }
 315
 316         addr = mm->mmap_base;
 317         while (addr > len) {
 318                 /* Go down by chunk size */
 319                 addr = _ALIGN_DOWN(addr - len, 1ul << pshift);
 320
 321                 /* Check for hit with different page size */
 322                 mask = slice_range_to_mask(addr, len);
 323                 if (!slice_check_fit(mask, available)) {
 324                         if (addr < SLICE_LOW_TOP)
 325                                 addr = _ALIGN_DOWN(addr, 1ul << SLICE_LOW_SHIFT);
 326                         else if (addr < (1ul << SLICE_HIGH_SHIFT))
 327                                 addr = SLICE_LOW_TOP;
 328                         else
 329                                 addr = _ALIGN_DOWN(addr, 1ul << SLICE_HIGH_SHIFT);
 330                         continue;
 331                 }
 332
 333                 /*
 334                  * Lookup failure means no vma is above this address,
 335                  * else if new region fits below vma->vm_start,
 336                  * return with success:
 337                  */
 338                 vma = find_vma(mm, addr);
 339                 if (!vma || (addr + len) <= vma->vm_start) {
 340                         /* remember the address as a hint for next time */
 341                         if (use_cache)
 342                                 mm->free_area_cache = addr;
 343                         return addr;
 344                 }
 345
 346                 /* remember the largest hole we saw so far */
 347                 if (use_cache && (addr + mm->cached_hole_size) < vma->vm_start)
 348                         mm->cached_hole_size = vma->vm_start - addr;
 349
 350                 /* try just below the current vma->vm_start */
 351                 addr = vma->vm_start;
 352         }
 353
 354         /*
 355          * A failed mmap() very likely causes application failure,
 356          * so fall back to the bottom-up function here. This scenario
 357          * can happen with large stack limits and large mmap()
 358          * allocations.
 359          */
 360         addr = slice_find_area_bottomup(mm, len, available, psize, 0);
 361
 362         /*
 363          * Restore the topdown base:
 364          */
 365         if (use_cache) {
 366                 mm->free_area_cache = mm->mmap_base;
 367                 mm->cached_hole_size = ~0UL;
 368         }
 369
 370         return addr;
 371 }
 372
 373
 374 static unsigned long slice_find_area(struct mm_struct *mm, unsigned long len,
 375                                      struct slice_mask mask, int psize,
 376                                      int topdown, int use_cache)
 377 {
 378         if (topdown)
 379                 return slice_find_area_topdown(mm, len, mask, psize, use_cache);
 380         else
 381                 return slice_find_area_bottomup(mm, len, mask, psize, use_cache);
 382 }
 383
 384 #define or_mask(dst, src)       do {                    \
 385         (dst).low_slices |= (src).low_slices;           \
 386         (dst).high_slices |= (src).high_slices;         \
 387 } while (0)
 388
 389 #define andnot_mask(dst, src)   do {                    \
 390         (dst).low_slices &= ~(src).low_slices;          \
 391         (dst).high_slices &= ~(src).high_slices;        \
 392 } while (0)
 393
 394 #ifdef CONFIG_PPC_64K_PAGES
 395 #define MMU_PAGE_BASE   MMU_PAGE_64K
 396 #else
 397 #define MMU_PAGE_BASE   MMU_PAGE_4K
 398 #endif
 399
 400 unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
 401                                       unsigned long flags, unsigned int psize,
 402                                       int topdown, int use_cache)
 403 {
 404         struct slice_mask mask = {0, 0};
 405         struct slice_mask good_mask;
 406         struct slice_mask potential_mask = {0,0} /* silence stupid warning */;
 407         struct slice_mask compat_mask = {0, 0};
 408         int fixed = (flags & MAP_FIXED);
 409         int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT);
 410         struct mm_struct *mm = current->mm;
 411         unsigned long newaddr;
 412
 413         /* Sanity checks */
 414         BUG_ON(mm->task_size == 0);
 415
 416         slice_dbg("slice_get_unmapped_area(mm=%p, psize=%d...\n", mm, psize);
 417         slice_dbg(" addr=%lx, len=%lx, flags=%lx, topdown=%d, use_cache=%d\n",
 418                   addr, len, flags, topdown, use_cache);
 419
 420         if (len > mm->task_size)
 421                 return -ENOMEM;
 422         if (len & ((1ul << pshift) - 1))
 423                 return -EINVAL;
 424         if (fixed && (addr & ((1ul << pshift) - 1)))
 425                 return -EINVAL;
 426         if (fixed && addr > (mm->task_size - len))
 427                 return -EINVAL;
 428
 429         /* If hint, make sure it matches our alignment restrictions */
 430         if (!fixed && addr) {
 431                 addr = _ALIGN_UP(addr, 1ul << pshift);
 432                 slice_dbg(" aligned addr=%lx\n", addr);
 433                 /* Ignore hint if it's too large or overlaps a VMA */
 434                 if (addr > mm->task_size - len ||
 435                     !slice_area_is_free(mm, addr, len))
 436                         addr = 0;
 437         }
 438
 439         /* First make up a "good" mask of slices that have the right size
 440          * already
 441          */
 442         good_mask = slice_mask_for_size(mm, psize);
 443         slice_print_mask(" good_mask", good_mask);
 444
 445         /*
 446          * Here "good" means slices that are already the right page size,
 447          * "compat" means slices that have a compatible page size (i.e.
 448          * 4k in a 64k pagesize kernel), and "free" means slices without
 449          * any VMAs.
 450          *
 451          * If MAP_FIXED:
 452          *      check if fits in good | compat => OK
 453          *      check if fits in good | compat | free => convert free
 454          *      else bad
 455          * If have hint:
 456          *      check if hint fits in good => OK
 457          *      check if hint fits in good | free => convert free
 458          * Otherwise:
 459          *      search in good, found => OK
 460          *      search in good | free, found => convert free
 461          *      search in good | compat | free, found => convert free.
 462          */
 463
 464 #ifdef CONFIG_PPC_64K_PAGES
 465         /* If we support combo pages, we can allow 64k pages in 4k slices */
 466         if (psize == MMU_PAGE_64K) {
 467                 compat_mask = slice_mask_for_size(mm, MMU_PAGE_4K);
 468                 if (fixed)
 469                         or_mask(good_mask, compat_mask);
 470         }
 471 #endif
 472
 473         /* First check hint if it's valid or if we have MAP_FIXED */
 474         if (addr != 0 || fixed) {
 475                 /* Build a mask for the requested range */
 476                 mask = slice_range_to_mask(addr, len);
 477                 slice_print_mask(" mask", mask);
 478
 479                 /* Check if we fit in the good mask. If we do, we just return,
 480                  * nothing else to do
 481                  */
 482                 if (slice_check_fit(mask, good_mask)) {
 483                         slice_dbg(" fits good !\n");
 484                         return addr;
 485                 }
 486         } else {
 487                 /* Now let's see if we can find something in the existing
 488                  * slices for that size
 489                  */
 490                 newaddr = slice_find_area(mm, len, good_mask, psize, topdown,
 491                                           use_cache);
 492                 if (newaddr != -ENOMEM) {
 493                         /* Found within the good mask, we don't have to setup,
 494                          * we thus return directly
 495                          */
 496                         slice_dbg(" found area at 0x%lx\n", newaddr);
 497                         return newaddr;
 498                 }
 499         }
 500
 501         /* We don't fit in the good mask, check what other slices are
 502          * empty and thus can be converted
 503          */
 504         potential_mask = slice_mask_for_free(mm);
 505         or_mask(potential_mask, good_mask);
 506         slice_print_mask(" potential", potential_mask);
 507
 508         if ((addr != 0 || fixed) && slice_check_fit(mask, potential_mask)) {
 509                 slice_dbg(" fits potential !\n");
 510                 goto convert;
 511         }
 512
 513         /* If we have MAP_FIXED and failed the above steps, then error out */
 514         if (fixed)
 515                 return -EBUSY;
 516
 517         slice_dbg(" search...\n");
 518
 519         /* If we had a hint that didn't work out, see if we can fit
 520          * anywhere in the good area.
 521          */
 522         if (addr) {
 523                 addr = slice_find_area(mm, len, good_mask, psize, topdown,
 524                                        use_cache);
 525                 if (addr != -ENOMEM) {
 526                         slice_dbg(" found area at 0x%lx\n", addr);
 527                         return addr;
 528                 }
 529         }
 530
 531         /* Now let's see if we can find something in the existing slices
 532          * for that size plus free slices
 533          */
 534         addr = slice_find_area(mm, len, potential_mask, psize, topdown,
 535                                use_cache);
 536
 537 #ifdef CONFIG_PPC_64K_PAGES
 538         if (addr == -ENOMEM && psize == MMU_PAGE_64K) {
 539                 /* retry the search with 4k-page slices included */
 540                 or_mask(potential_mask, compat_mask);
 541                 addr = slice_find_area(mm, len, potential_mask, psize,
 542                                        topdown, use_cache);
 543         }
 544 #endif
 545
 546         if (addr == -ENOMEM)
 547                 return -ENOMEM;
 548
 549         mask = slice_range_to_mask(addr, len);
 550         slice_dbg(" found potential area at 0x%lx\n", addr);
 551         slice_print_mask(" mask", mask);
 552
 553  convert:
 554         andnot_mask(mask, good_mask);
 555         andnot_mask(mask, compat_mask);
 556         if (mask.low_slices || mask.high_slices) {
 557                 slice_convert(mm, mask, psize);
 558                 if (psize > MMU_PAGE_BASE)
 559                         on_each_cpu(slice_flush_segments, mm, 1);
 560         }
 561         return addr;
 562
 563 }
 564 EXPORT_SYMBOL_GPL(slice_get_unmapped_area);
 565
 566 unsigned long arch_get_unmapped_area(struct file *filp,
 567                                      unsigned long addr,
 568                                      unsigned long len,
 569                                      unsigned long pgoff,
 570                                      unsigned long flags)
 571 {
 572         return slice_get_unmapped_area(addr, len, flags,
 573                                        current->mm->context.user_psize,
 574                                        0, 1);
 575 }
 576
 577 unsigned long arch_get_unmapped_area_topdown(struct file *filp,
 578                                              const unsigned long addr0,
 579                                              const unsigned long len,
 580                                              const unsigned long pgoff,
 581                                              const unsigned long flags)
 582 {
 583         return slice_get_unmapped_area(addr0, len, flags,
 584                                        current->mm->context.user_psize,
 585                                        1, 1);
 586 }
 587
 588 unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
 589 {
 590         u64 psizes;
 591         int index;
 592
 593         if (addr < SLICE_LOW_TOP) {
 594                 psizes = mm->context.low_slices_psize;
 595                 index = GET_LOW_SLICE_INDEX(addr);
 596         } else {
 597                 psizes = mm->context.high_slices_psize;
 598                 index = GET_HIGH_SLICE_INDEX(addr);
 599         }
 600
 601         return (psizes >> (index * 4)) & 0xf;
 602 }
 603 EXPORT_SYMBOL_GPL(get_slice_psize);
 604
 605 /*
 606  * This is called by hash_page when it needs to do a lazy conversion of
 607  * an address space from real 64K pages to combo 4K pages (typically
 608  * when hitting a non cacheable mapping on a processor or hypervisor
 609  * that won't allow them for 64K pages).
 610  *
 611  * This is also called in init_new_context() to change back the user
 612  * psize from whatever the parent context had it set to
 613  * N.B. This may be called before mm->context.id has been set.
 614  *
 615  * This function will only change the content of the {low,high)_slice_psize
 616  * masks, it will not flush SLBs as this shall be handled lazily by the
 617  * caller.
 618  */
 619 void slice_set_user_psize(struct mm_struct *mm, unsigned int psize)
 620 {
 621         unsigned long flags, lpsizes, hpsizes;
 622         unsigned int old_psize;
 623         int i;
 624
 625         slice_dbg("slice_set_user_psize(mm=%p, psize=%d)\n", mm, psize);
 626
 627         spin_lock_irqsave(&slice_convert_lock, flags);
 628
 629         old_psize = mm->context.user_psize;
 630         slice_dbg(" old_psize=%d\n", old_psize);
 631         if (old_psize == psize)
 632                 goto bail;
 633
 634         mm->context.user_psize = psize;
 635         wmb();
 636
 637         lpsizes = mm->context.low_slices_psize;
 638         for (i = 0; i < SLICE_NUM_LOW; i++)
 639                 if (((lpsizes >> (i * 4)) & 0xf) == old_psize)
 640                         lpsizes = (lpsizes & ~(0xful << (i * 4))) |
 641                                 (((unsigned long)psize) << (i * 4));
 642
 643         hpsizes = mm->context.high_slices_psize;
 644         for (i = 0; i < SLICE_NUM_HIGH; i++)
 645                 if (((hpsizes >> (i * 4)) & 0xf) == old_psize)
 646                         hpsizes = (hpsizes & ~(0xful << (i * 4))) |
 647                                 (((unsigned long)psize) << (i * 4));
 648
 649         mm->context.low_slices_psize = lpsizes;
 650         mm->context.high_slices_psize = hpsizes;
 651
 652         slice_dbg(" lsps=%lx, hsps=%lx\n",
 653                   mm->context.low_slices_psize,
 654                   mm->context.high_slices_psize);
 655
 656  bail:
 657         spin_unlock_irqrestore(&slice_convert_lock, flags);
 658 }
 659
 660 void slice_set_psize(struct mm_struct *mm, unsigned long address,
 661                      unsigned int psize)
 662 {
 663         unsigned long i, flags;
 664         u64 *p;
 665
 666         spin_lock_irqsave(&slice_convert_lock, flags);
 667         if (address < SLICE_LOW_TOP) {
 668                 i = GET_LOW_SLICE_INDEX(address);
 669                 p = &mm->context.low_slices_psize;
 670         } else {
 671                 i = GET_HIGH_SLICE_INDEX(address);
 672                 p = &mm->context.high_slices_psize;
 673         }
 674         *p = (*p & ~(0xful << (i * 4))) | ((unsigned long) psize << (i * 4));
 675         spin_unlock_irqrestore(&slice_convert_lock, flags);
 676
 677 #ifdef CONFIG_SPU_BASE
 678         spu_flush_all_slbs(mm);
 679 #endif
 680 }
 681
 682 void slice_set_range_psize(struct mm_struct *mm, unsigned long start,
 683                            unsigned long len, unsigned int psize)
 684 {
 685         struct slice_mask mask = slice_range_to_mask(start, len);
 686
 687         slice_convert(mm, mask, psize);
 688 }
 689
 690 /*
 691  * is_hugepage_only_range() is used by generic code to verify wether
 692  * a normal mmap mapping (non hugetlbfs) is valid on a given area.
 693  *
 694  * until the generic code provides a more generic hook and/or starts
 695  * calling arch get_unmapped_area for MAP_FIXED (which our implementation
 696  * here knows how to deal with), we hijack it to keep standard mappings
 697  * away from us.
 698  *
 699  * because of that generic code limitation, MAP_FIXED mapping cannot
 700  * "convert" back a slice with no VMAs to the standard page size, only
 701  * get_unmapped_area() can. It would be possible to fix it here but I
 702  * prefer working on fixing the generic code instead.
 703  *
 704  * WARNING: This will not work if hugetlbfs isn't enabled since the
 705  * generic code will redefine that function as 0 in that. This is ok
 706  * for now as we only use slices with hugetlbfs enabled. This should
 707  * be fixed as the generic code gets fixed.
 708  */
 709 int is_hugepage_only_range(struct mm_struct *mm, unsigned long addr,
 710                            unsigned long len)
 711 {
 712         struct slice_mask mask, available;
 713         unsigned int psize = mm->context.user_psize;
 714
 715         mask = slice_range_to_mask(addr, len);
 716         available = slice_mask_for_size(mm, psize);
 717 #ifdef CONFIG_PPC_64K_PAGES
 718         /* We need to account for 4k slices too */
 719         if (psize == MMU_PAGE_64K) {
 720                 struct slice_mask compat_mask;
 721                 compat_mask = slice_mask_for_size(mm, MMU_PAGE_4K);
 722                 or_mask(available, compat_mask);
 723         }
 724 #endif
 725
 726 #if 0 /* too verbose */
 727         slice_dbg("is_hugepage_only_range(mm=%p, addr=%lx, len=%lx)\n",
 728                  mm, addr, len);
 729         slice_print_mask(" mask", mask);
 730         slice_print_mask(" available", available);
 731 #endif
 732         return !slice_check_fit(mask, available);
 733 }
 734