diff options
Diffstat (limited to 'arch/powerpc/mm/slice.c')
| -rw-r--r-- | arch/powerpc/mm/slice.c | 731 |
1 files changed, 0 insertions, 731 deletions
diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c deleted file mode 100644 index 3e99c149271a..000000000000 --- a/arch/powerpc/mm/slice.c +++ /dev/null @@ -1,731 +0,0 @@ -/* - * address space "slices" (meta-segments) support - * - * Copyright (C) 2007 Benjamin Herrenschmidt, IBM Corporation. - * - * Based on hugetlb implementation - * - * Copyright (C) 2003 David Gibson, IBM Corporation. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - */ - -#undef DEBUG - -#include <linux/kernel.h> -#include <linux/mm.h> -#include <linux/pagemap.h> -#include <linux/err.h> -#include <linux/spinlock.h> -#include <linux/export.h> -#include <asm/mman.h> -#include <asm/mmu.h> -#include <asm/spu.h> - -/* some sanity checks */ -#if (PGTABLE_RANGE >> 43) > SLICE_MASK_SIZE -#error PGTABLE_RANGE exceeds slice_mask high_slices size -#endif - -static DEFINE_SPINLOCK(slice_convert_lock); - - -#ifdef DEBUG -int _slice_debug = 1; - -static void slice_print_mask(const char *label, struct slice_mask mask) -{ - char *p, buf[16 + 3 + 64 + 1]; - int i; - - if (!_slice_debug) - return; - p = buf; - for (i = 0; i < SLICE_NUM_LOW; i++) - *(p++) = (mask.low_slices & (1 << i)) ? '1' : '0'; - *(p++) = ' '; - *(p++) = '-'; - *(p++) = ' '; - for (i = 0; i < SLICE_NUM_HIGH; i++) - *(p++) = (mask.high_slices & (1ul << i)) ? '1' : '0'; - *(p++) = 0; - - printk(KERN_DEBUG "%s:%s\n", label, buf); -} - -#define slice_dbg(fmt...) do { if (_slice_debug) pr_debug(fmt); } while(0) - -#else - -static void slice_print_mask(const char *label, struct slice_mask mask) {} -#define slice_dbg(fmt...) - -#endif - -static struct slice_mask slice_range_to_mask(unsigned long start, - unsigned long len) -{ - unsigned long end = start + len - 1; - struct slice_mask ret = { 0, 0 }; - - if (start < SLICE_LOW_TOP) { - unsigned long mend = min(end, SLICE_LOW_TOP); - unsigned long mstart = min(start, SLICE_LOW_TOP); - - ret.low_slices = (1u << (GET_LOW_SLICE_INDEX(mend) + 1)) - - (1u << GET_LOW_SLICE_INDEX(mstart)); - } - - if ((start + len) > SLICE_LOW_TOP) - ret.high_slices = (1ul << (GET_HIGH_SLICE_INDEX(end) + 1)) - - (1ul << GET_HIGH_SLICE_INDEX(start)); - - return ret; -} - -static int slice_area_is_free(struct mm_struct *mm, unsigned long addr, - unsigned long len) -{ - struct vm_area_struct *vma; - - if ((mm->task_size - len) < addr) - return 0; - vma = find_vma(mm, addr); - return (!vma || (addr + len) <= vma->vm_start); -} - -static int slice_low_has_vma(struct mm_struct *mm, unsigned long slice) -{ - return !slice_area_is_free(mm, slice << SLICE_LOW_SHIFT, - 1ul << SLICE_LOW_SHIFT); -} - -static int slice_high_has_vma(struct mm_struct *mm, unsigned long slice) -{ - unsigned long start = slice << SLICE_HIGH_SHIFT; - unsigned long end = start + (1ul << SLICE_HIGH_SHIFT); - - /* Hack, so that each addresses is controlled by exactly one - * of the high or low area bitmaps, the first high area starts - * at 4GB, not 0 */ - if (start == 0) - start = SLICE_LOW_TOP; - - return !slice_area_is_free(mm, start, end - start); -} - -static struct slice_mask slice_mask_for_free(struct mm_struct *mm) -{ - struct slice_mask ret = { 0, 0 }; - unsigned long i; - - for (i = 0; i < SLICE_NUM_LOW; i++) - if (!slice_low_has_vma(mm, i)) - ret.low_slices |= 1u << i; - - if (mm->task_size <= SLICE_LOW_TOP) - return ret; - - for (i = 0; i < SLICE_NUM_HIGH; i++) - if (!slice_high_has_vma(mm, i)) - ret.high_slices |= 1ul << i; - - return ret; -} - -static struct slice_mask slice_mask_for_size(struct mm_struct *mm, int psize) -{ - unsigned char *hpsizes; - int index, mask_index; - struct slice_mask ret = { 0, 0 }; - unsigned long i; - u64 lpsizes; - - lpsizes = mm->context.low_slices_psize; - for (i = 0; i < SLICE_NUM_LOW; i++) - if (((lpsizes >> (i * 4)) & 0xf) == psize) - ret.low_slices |= 1u << i; - - hpsizes = mm->context.high_slices_psize; - for (i = 0; i < SLICE_NUM_HIGH; i++) { - mask_index = i & 0x1; - index = i >> 1; - if (((hpsizes[index] >> (mask_index * 4)) & 0xf) == psize) - ret.high_slices |= 1ul << i; - } - - return ret; -} - -static int slice_check_fit(struct slice_mask mask, struct slice_mask available) -{ - return (mask.low_slices & available.low_slices) == mask.low_slices && - (mask.high_slices & available.high_slices) == mask.high_slices; -} - -static void slice_flush_segments(void *parm) -{ - struct mm_struct *mm = parm; - unsigned long flags; - - if (mm != current->active_mm) - return; - - /* update the paca copy of the context struct */ - get_paca()->context = current->active_mm->context; - - local_irq_save(flags); - slb_flush_and_rebolt(); - local_irq_restore(flags); -} - -static void slice_convert(struct mm_struct *mm, struct slice_mask mask, int psize) -{ - int index, mask_index; - /* Write the new slice psize bits */ - unsigned char *hpsizes; - u64 lpsizes; - unsigned long i, flags; - - slice_dbg("slice_convert(mm=%p, psize=%d)\n", mm, psize); - slice_print_mask(" mask", mask); - - /* We need to use a spinlock here to protect against - * concurrent 64k -> 4k demotion ... - */ - spin_lock_irqsave(&slice_convert_lock, flags); - - lpsizes = mm->context.low_slices_psize; - for (i = 0; i < SLICE_NUM_LOW; i++) - if (mask.low_slices & (1u << i)) - lpsizes = (lpsizes & ~(0xful << (i * 4))) | - (((unsigned long)psize) << (i * 4)); - - /* Assign the value back */ - mm->context.low_slices_psize = lpsizes; - - hpsizes = mm->context.high_slices_psize; - for (i = 0; i < SLICE_NUM_HIGH; i++) { - mask_index = i & 0x1; - index = i >> 1; - if (mask.high_slices & (1ul << i)) - hpsizes[index] = (hpsizes[index] & - ~(0xf << (mask_index * 4))) | - (((unsigned long)psize) << (mask_index * 4)); - } - - slice_dbg(" lsps=%lx, hsps=%lx\n", - mm->context.low_slices_psize, - mm->context.high_slices_psize); - - spin_unlock_irqrestore(&slice_convert_lock, flags); - -#ifdef CONFIG_SPU_BASE - spu_flush_all_slbs(mm); -#endif -} - -/* - * Compute which slice addr is part of; - * set *boundary_addr to the start or end boundary of that slice - * (depending on 'end' parameter); - * return boolean indicating if the slice is marked as available in the - * 'available' slice_mark. - */ -static bool slice_scan_available(unsigned long addr, - struct slice_mask available, - int end, - unsigned long *boundary_addr) -{ - unsigned long slice; - if (addr < SLICE_LOW_TOP) { - slice = GET_LOW_SLICE_INDEX(addr); - *boundary_addr = (slice + end) << SLICE_LOW_SHIFT; - return !!(available.low_slices & (1u << slice)); - } else { - slice = GET_HIGH_SLICE_INDEX(addr); - *boundary_addr = (slice + end) ? - ((slice + end) << SLICE_HIGH_SHIFT) : SLICE_LOW_TOP; - return !!(available.high_slices & (1u << slice)); - } -} - -static unsigned long slice_find_area_bottomup(struct mm_struct *mm, - unsigned long len, - struct slice_mask available, - int psize) -{ - int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT); - unsigned long addr, found, next_end; - struct vm_unmapped_area_info info; - - info.flags = 0; - info.length = len; - info.align_mask = PAGE_MASK & ((1ul << pshift) - 1); - info.align_offset = 0; - - addr = TASK_UNMAPPED_BASE; - while (addr < TASK_SIZE) { - info.low_limit = addr; - if (!slice_scan_available(addr, available, 1, &addr)) - continue; - - next_slice: - /* - * At this point [info.low_limit; addr) covers - * available slices only and ends at a slice boundary. - * Check if we need to reduce the range, or if we can - * extend it to cover the next available slice. - */ - if (addr >= TASK_SIZE) - addr = TASK_SIZE; - else if (slice_scan_available(addr, available, 1, &next_end)) { - addr = next_end; - goto next_slice; - } - info.high_limit = addr; - - found = vm_unmapped_area(&info); - if (!(found & ~PAGE_MASK)) - return found; - } - - return -ENOMEM; -} - -static unsigned long slice_find_area_topdown(struct mm_struct *mm, - unsigned long len, - struct slice_mask available, - int psize) -{ - int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT); - unsigned long addr, found, prev; - struct vm_unmapped_area_info info; - - info.flags = VM_UNMAPPED_AREA_TOPDOWN; - info.length = len; - info.align_mask = PAGE_MASK & ((1ul << pshift) - 1); - info.align_offset = 0; - - addr = mm->mmap_base; - while (addr > PAGE_SIZE) { - info.high_limit = addr; - if (!slice_scan_available(addr - 1, available, 0, &addr)) - continue; - - prev_slice: - /* - * At this point [addr; info.high_limit) covers - * available slices only and starts at a slice boundary. - * Check if we need to reduce the range, or if we can - * extend it to cover the previous available slice. - */ - if (addr < PAGE_SIZE) - addr = PAGE_SIZE; - else if (slice_scan_available(addr - 1, available, 0, &prev)) { - addr = prev; - goto prev_slice; - } - info.low_limit = addr; - - found = vm_unmapped_area(&info); - if (!(found & ~PAGE_MASK)) - return found; - } - - /* - * A failed mmap() very likely causes application failure, - * so fall back to the bottom-up function here. This scenario - * can happen with large stack limits and large mmap() - * allocations. - */ - return slice_find_area_bottomup(mm, len, available, psize); -} - - -static unsigned long slice_find_area(struct mm_struct *mm, unsigned long len, - struct slice_mask mask, int psize, - int topdown) -{ - if (topdown) - return slice_find_area_topdown(mm, len, mask, psize); - else - return slice_find_area_bottomup(mm, len, mask, psize); -} - -#define or_mask(dst, src) do { \ - (dst).low_slices |= (src).low_slices; \ - (dst).high_slices |= (src).high_slices; \ -} while (0) - -#define andnot_mask(dst, src) do { \ - (dst).low_slices &= ~(src).low_slices; \ - (dst).high_slices &= ~(src).high_slices; \ -} while (0) - -#ifdef CONFIG_PPC_64K_PAGES -#define MMU_PAGE_BASE MMU_PAGE_64K -#else -#define MMU_PAGE_BASE MMU_PAGE_4K -#endif - -unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len, - unsigned long flags, unsigned int psize, - int topdown) -{ - struct slice_mask mask = {0, 0}; - struct slice_mask good_mask; - struct slice_mask potential_mask = {0,0} /* silence stupid warning */; - struct slice_mask compat_mask = {0, 0}; - int fixed = (flags & MAP_FIXED); - int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT); - struct mm_struct *mm = current->mm; - unsigned long newaddr; - - /* Sanity checks */ - BUG_ON(mm->task_size == 0); - - slice_dbg("slice_get_unmapped_area(mm=%p, psize=%d...\n", mm, psize); - slice_dbg(" addr=%lx, len=%lx, flags=%lx, topdown=%d\n", - addr, len, flags, topdown); - - if (len > mm->task_size) - return -ENOMEM; - if (len & ((1ul << pshift) - 1)) - return -EINVAL; - if (fixed && (addr & ((1ul << pshift) - 1))) - return -EINVAL; - if (fixed && addr > (mm->task_size - len)) - return -EINVAL; - - /* If hint, make sure it matches our alignment restrictions */ - if (!fixed && addr) { - addr = _ALIGN_UP(addr, 1ul << pshift); - slice_dbg(" aligned addr=%lx\n", addr); - /* Ignore hint if it's too large or overlaps a VMA */ - if (addr > mm->task_size - len || - !slice_area_is_free(mm, addr, len)) - addr = 0; - } - - /* First make up a "good" mask of slices that have the right size - * already - */ - good_mask = slice_mask_for_size(mm, psize); - slice_print_mask(" good_mask", good_mask); - - /* - * Here "good" means slices that are already the right page size, - * "compat" means slices that have a compatible page size (i.e. - * 4k in a 64k pagesize kernel), and "free" means slices without - * any VMAs. - * - * If MAP_FIXED: - * check if fits in good | compat => OK - * check if fits in good | compat | free => convert free - * else bad - * If have hint: - * check if hint fits in good => OK - * check if hint fits in good | free => convert free - * Otherwise: - * search in good, found => OK - * search in good | free, found => convert free - * search in good | compat | free, found => convert free. - */ - -#ifdef CONFIG_PPC_64K_PAGES - /* If we support combo pages, we can allow 64k pages in 4k slices */ - if (psize == MMU_PAGE_64K) { - compat_mask = slice_mask_for_size(mm, MMU_PAGE_4K); - if (fixed) - or_mask(good_mask, compat_mask); - } -#endif - - /* First check hint if it's valid or if we have MAP_FIXED */ - if (addr != 0 || fixed) { - /* Build a mask for the requested range */ - mask = slice_range_to_mask(addr, len); - slice_print_mask(" mask", mask); - - /* Check if we fit in the good mask. If we do, we just return, - * nothing else to do - */ - if (slice_check_fit(mask, good_mask)) { - slice_dbg(" fits good !\n"); - return addr; - } - } else { - /* Now let's see if we can find something in the existing - * slices for that size - */ - newaddr = slice_find_area(mm, len, good_mask, psize, topdown); - if (newaddr != -ENOMEM) { - /* Found within the good mask, we don't have to setup, - * we thus return directly - */ - slice_dbg(" found area at 0x%lx\n", newaddr); - return newaddr; - } - } - - /* We don't fit in the good mask, check what other slices are - * empty and thus can be converted - */ - potential_mask = slice_mask_for_free(mm); - or_mask(potential_mask, good_mask); - slice_print_mask(" potential", potential_mask); - - if ((addr != 0 || fixed) && slice_check_fit(mask, potential_mask)) { - slice_dbg(" fits potential !\n"); - goto convert; - } - - /* If we have MAP_FIXED and failed the above steps, then error out */ - if (fixed) - return -EBUSY; - - slice_dbg(" search...\n"); - - /* If we had a hint that didn't work out, see if we can fit - * anywhere in the good area. - */ - if (addr) { - addr = slice_find_area(mm, len, good_mask, psize, topdown); - if (addr != -ENOMEM) { - slice_dbg(" found area at 0x%lx\n", addr); - return addr; - } - } - - /* Now let's see if we can find something in the existing slices - * for that size plus free slices - */ - addr = slice_find_area(mm, len, potential_mask, psize, topdown); - -#ifdef CONFIG_PPC_64K_PAGES - if (addr == -ENOMEM && psize == MMU_PAGE_64K) { - /* retry the search with 4k-page slices included */ - or_mask(potential_mask, compat_mask); - addr = slice_find_area(mm, len, potential_mask, psize, - topdown); - } -#endif - - if (addr == -ENOMEM) - return -ENOMEM; - - mask = slice_range_to_mask(addr, len); - slice_dbg(" found potential area at 0x%lx\n", addr); - slice_print_mask(" mask", mask); - - convert: - andnot_mask(mask, good_mask); - andnot_mask(mask, compat_mask); - if (mask.low_slices || mask.high_slices) { - slice_convert(mm, mask, psize); - if (psize > MMU_PAGE_BASE) - on_each_cpu(slice_flush_segments, mm, 1); - } - return addr; - -} -EXPORT_SYMBOL_GPL(slice_get_unmapped_area); - -unsigned long arch_get_unmapped_area(struct file *filp, - unsigned long addr, - unsigned long len, - unsigned long pgoff, - unsigned long flags) -{ - return slice_get_unmapped_area(addr, len, flags, - current->mm->context.user_psize, 0); -} - -unsigned long arch_get_unmapped_area_topdown(struct file *filp, - const unsigned long addr0, - const unsigned long len, - const unsigned long pgoff, - const unsigned long flags) -{ - return slice_get_unmapped_area(addr0, len, flags, - current->mm->context.user_psize, 1); -} - -unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr) -{ - unsigned char *hpsizes; - int index, mask_index; - - if (addr < SLICE_LOW_TOP) { - u64 lpsizes; - lpsizes = mm->context.low_slices_psize; - index = GET_LOW_SLICE_INDEX(addr); - return (lpsizes >> (index * 4)) & 0xf; - } - hpsizes = mm->context.high_slices_psize; - index = GET_HIGH_SLICE_INDEX(addr); - mask_index = index & 0x1; - return (hpsizes[index >> 1] >> (mask_index * 4)) & 0xf; -} -EXPORT_SYMBOL_GPL(get_slice_psize); - -/* - * This is called by hash_page when it needs to do a lazy conversion of - * an address space from real 64K pages to combo 4K pages (typically - * when hitting a non cacheable mapping on a processor or hypervisor - * that won't allow them for 64K pages). - * - * This is also called in init_new_context() to change back the user - * psize from whatever the parent context had it set to - * N.B. This may be called before mm->context.id has been set. - * - * This function will only change the content of the {low,high)_slice_psize - * masks, it will not flush SLBs as this shall be handled lazily by the - * caller. - */ -void slice_set_user_psize(struct mm_struct *mm, unsigned int psize) -{ - int index, mask_index; - unsigned char *hpsizes; - unsigned long flags, lpsizes; - unsigned int old_psize; - int i; - - slice_dbg("slice_set_user_psize(mm=%p, psize=%d)\n", mm, psize); - - spin_lock_irqsave(&slice_convert_lock, flags); - - old_psize = mm->context.user_psize; - slice_dbg(" old_psize=%d\n", old_psize); - if (old_psize == psize) - goto bail; - - mm->context.user_psize = psize; - wmb(); - - lpsizes = mm->context.low_slices_psize; - for (i = 0; i < SLICE_NUM_LOW; i++) - if (((lpsizes >> (i * 4)) & 0xf) == old_psize) - lpsizes = (lpsizes & ~(0xful << (i * 4))) | - (((unsigned long)psize) << (i * 4)); - /* Assign the value back */ - mm->context.low_slices_psize = lpsizes; - - hpsizes = mm->context.high_slices_psize; - for (i = 0; i < SLICE_NUM_HIGH; i++) { - mask_index = i & 0x1; - index = i >> 1; - if (((hpsizes[index] >> (mask_index * 4)) & 0xf) == old_psize) - hpsizes[index] = (hpsizes[index] & - ~(0xf << (mask_index * 4))) | - (((unsigned long)psize) << (mask_index * 4)); - } - - - - - slice_dbg(" lsps=%lx, hsps=%lx\n", - mm->context.low_slices_psize, - mm->context.high_slices_psize); - - bail: - spin_unlock_irqrestore(&slice_convert_lock, flags); -} - -void slice_set_psize(struct mm_struct *mm, unsigned long address, - unsigned int psize) -{ - unsigned char *hpsizes; - unsigned long i, flags; - u64 *lpsizes; - - spin_lock_irqsave(&slice_convert_lock, flags); - if (address < SLICE_LOW_TOP) { - i = GET_LOW_SLICE_INDEX(address); - lpsizes = &mm->context.low_slices_psize; - *lpsizes = (*lpsizes & ~(0xful << (i * 4))) | - ((unsigned long) psize << (i * 4)); - } else { - int index, mask_index; - i = GET_HIGH_SLICE_INDEX(address); - hpsizes = mm->context.high_slices_psize; - mask_index = i & 0x1; - index = i >> 1; - hpsizes[index] = (hpsizes[index] & - ~(0xf << (mask_index * 4))) | - (((unsigned long)psize) << (mask_index * 4)); - } - - spin_unlock_irqrestore(&slice_convert_lock, flags); - -#ifdef CONFIG_SPU_BASE - spu_flush_all_slbs(mm); -#endif -} - -void slice_set_range_psize(struct mm_struct *mm, unsigned long start, - unsigned long len, unsigned int psize) -{ - struct slice_mask mask = slice_range_to_mask(start, len); - - slice_convert(mm, mask, psize); -} - -/* - * is_hugepage_only_range() is used by generic code to verify whether - * a normal mmap mapping (non hugetlbfs) is valid on a given area. - * - * until the generic code provides a more generic hook and/or starts - * calling arch get_unmapped_area for MAP_FIXED (which our implementation - * here knows how to deal with), we hijack it to keep standard mappings - * away from us. - * - * because of that generic code limitation, MAP_FIXED mapping cannot - * "convert" back a slice with no VMAs to the standard page size, only - * get_unmapped_area() can. It would be possible to fix it here but I - * prefer working on fixing the generic code instead. - * - * WARNING: This will not work if hugetlbfs isn't enabled since the - * generic code will redefine that function as 0 in that. This is ok - * for now as we only use slices with hugetlbfs enabled. This should - * be fixed as the generic code gets fixed. - */ -int is_hugepage_only_range(struct mm_struct *mm, unsigned long addr, - unsigned long len) -{ - struct slice_mask mask, available; - unsigned int psize = mm->context.user_psize; - - mask = slice_range_to_mask(addr, len); - available = slice_mask_for_size(mm, psize); -#ifdef CONFIG_PPC_64K_PAGES - /* We need to account for 4k slices too */ - if (psize == MMU_PAGE_64K) { - struct slice_mask compat_mask; - compat_mask = slice_mask_for_size(mm, MMU_PAGE_4K); - or_mask(available, compat_mask); - } -#endif - -#if 0 /* too verbose */ - slice_dbg("is_hugepage_only_range(mm=%p, addr=%lx, len=%lx)\n", - mm, addr, len); - slice_print_mask(" mask", mask); - slice_print_mask(" available", available); -#endif - return !slice_check_fit(mask, available); -} - |
