773 lines
22 KiB
C
773 lines
22 KiB
C
/*
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* address space "slices" (meta-segments) support
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*
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* Copyright (C) 2007 Benjamin Herrenschmidt, IBM Corporation.
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*
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* Based on hugetlb implementation
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*
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* Copyright (C) 2003 David Gibson, IBM Corporation.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#undef DEBUG
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#include <linux/kernel.h>
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#include <linux/mm.h>
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#include <linux/pagemap.h>
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#include <linux/err.h>
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#include <linux/spinlock.h>
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#include <linux/export.h>
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#include <linux/hugetlb.h>
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#include <asm/mman.h>
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#include <asm/mmu.h>
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#include <asm/copro.h>
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#include <asm/hugetlb.h>
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static DEFINE_SPINLOCK(slice_convert_lock);
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/*
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* One bit per slice. We have lower slices which cover 256MB segments
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* upto 4G range. That gets us 16 low slices. For the rest we track slices
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* in 1TB size.
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*/
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struct slice_mask {
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u64 low_slices;
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DECLARE_BITMAP(high_slices, SLICE_NUM_HIGH);
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};
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#ifdef DEBUG
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int _slice_debug = 1;
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static void slice_print_mask(const char *label, struct slice_mask mask)
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{
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if (!_slice_debug)
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return;
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pr_devel("%s low_slice: %*pbl\n", label, (int)SLICE_NUM_LOW, &mask.low_slices);
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pr_devel("%s high_slice: %*pbl\n", label, (int)SLICE_NUM_HIGH, mask.high_slices);
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}
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#define slice_dbg(fmt...) do { if (_slice_debug) pr_devel(fmt); } while (0)
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#else
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static void slice_print_mask(const char *label, struct slice_mask mask) {}
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#define slice_dbg(fmt...)
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#endif
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static void slice_range_to_mask(unsigned long start, unsigned long len,
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struct slice_mask *ret)
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{
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unsigned long end = start + len - 1;
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ret->low_slices = 0;
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bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
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if (start < SLICE_LOW_TOP) {
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unsigned long mend = min(end, (SLICE_LOW_TOP - 1));
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ret->low_slices = (1u << (GET_LOW_SLICE_INDEX(mend) + 1))
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- (1u << GET_LOW_SLICE_INDEX(start));
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}
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if ((start + len) > SLICE_LOW_TOP) {
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unsigned long start_index = GET_HIGH_SLICE_INDEX(start);
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unsigned long align_end = ALIGN(end, (1UL << SLICE_HIGH_SHIFT));
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unsigned long count = GET_HIGH_SLICE_INDEX(align_end) - start_index;
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bitmap_set(ret->high_slices, start_index, count);
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}
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}
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static int slice_area_is_free(struct mm_struct *mm, unsigned long addr,
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unsigned long len)
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{
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struct vm_area_struct *vma;
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if ((mm->task_size - len) < addr)
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return 0;
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vma = find_vma(mm, addr);
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return (!vma || (addr + len) <= vm_start_gap(vma));
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}
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static int slice_low_has_vma(struct mm_struct *mm, unsigned long slice)
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{
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return !slice_area_is_free(mm, slice << SLICE_LOW_SHIFT,
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1ul << SLICE_LOW_SHIFT);
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}
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static int slice_high_has_vma(struct mm_struct *mm, unsigned long slice)
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{
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unsigned long start = slice << SLICE_HIGH_SHIFT;
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unsigned long end = start + (1ul << SLICE_HIGH_SHIFT);
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/* Hack, so that each addresses is controlled by exactly one
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* of the high or low area bitmaps, the first high area starts
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* at 4GB, not 0 */
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if (start == 0)
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start = SLICE_LOW_TOP;
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return !slice_area_is_free(mm, start, end - start);
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}
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static void slice_mask_for_free(struct mm_struct *mm, struct slice_mask *ret)
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{
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unsigned long i;
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ret->low_slices = 0;
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bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
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for (i = 0; i < SLICE_NUM_LOW; i++)
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if (!slice_low_has_vma(mm, i))
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ret->low_slices |= 1u << i;
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if (mm->task_size <= SLICE_LOW_TOP)
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return;
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for (i = 0; i < GET_HIGH_SLICE_INDEX(mm->context.addr_limit); i++)
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if (!slice_high_has_vma(mm, i))
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__set_bit(i, ret->high_slices);
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}
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static void slice_mask_for_size(struct mm_struct *mm, int psize, struct slice_mask *ret)
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{
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unsigned char *hpsizes;
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int index, mask_index;
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unsigned long i;
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u64 lpsizes;
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ret->low_slices = 0;
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bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
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lpsizes = mm->context.low_slices_psize;
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for (i = 0; i < SLICE_NUM_LOW; i++)
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if (((lpsizes >> (i * 4)) & 0xf) == psize)
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ret->low_slices |= 1u << i;
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hpsizes = mm->context.high_slices_psize;
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for (i = 0; i < GET_HIGH_SLICE_INDEX(mm->context.addr_limit); i++) {
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mask_index = i & 0x1;
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index = i >> 1;
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if (((hpsizes[index] >> (mask_index * 4)) & 0xf) == psize)
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__set_bit(i, ret->high_slices);
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}
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}
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static int slice_check_fit(struct mm_struct *mm,
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struct slice_mask mask, struct slice_mask available)
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{
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DECLARE_BITMAP(result, SLICE_NUM_HIGH);
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unsigned long slice_count = GET_HIGH_SLICE_INDEX(mm->context.addr_limit);
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bitmap_and(result, mask.high_slices,
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available.high_slices, slice_count);
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return (mask.low_slices & available.low_slices) == mask.low_slices &&
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bitmap_equal(result, mask.high_slices, slice_count);
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}
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static void slice_flush_segments(void *parm)
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{
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struct mm_struct *mm = parm;
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unsigned long flags;
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if (mm != current->active_mm)
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return;
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copy_mm_to_paca(current->active_mm);
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local_irq_save(flags);
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slb_flush_and_rebolt();
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local_irq_restore(flags);
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}
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static void slice_convert(struct mm_struct *mm, struct slice_mask mask, int psize)
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{
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int index, mask_index;
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/* Write the new slice psize bits */
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unsigned char *hpsizes;
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u64 lpsizes;
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unsigned long i, flags;
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slice_dbg("slice_convert(mm=%p, psize=%d)\n", mm, psize);
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slice_print_mask(" mask", mask);
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/* We need to use a spinlock here to protect against
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* concurrent 64k -> 4k demotion ...
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*/
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spin_lock_irqsave(&slice_convert_lock, flags);
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lpsizes = mm->context.low_slices_psize;
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for (i = 0; i < SLICE_NUM_LOW; i++)
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if (mask.low_slices & (1u << i))
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lpsizes = (lpsizes & ~(0xful << (i * 4))) |
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(((unsigned long)psize) << (i * 4));
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/* Assign the value back */
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mm->context.low_slices_psize = lpsizes;
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hpsizes = mm->context.high_slices_psize;
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for (i = 0; i < GET_HIGH_SLICE_INDEX(mm->context.addr_limit); i++) {
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mask_index = i & 0x1;
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index = i >> 1;
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if (test_bit(i, mask.high_slices))
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hpsizes[index] = (hpsizes[index] &
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~(0xf << (mask_index * 4))) |
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(((unsigned long)psize) << (mask_index * 4));
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}
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slice_dbg(" lsps=%lx, hsps=%lx\n",
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(unsigned long)mm->context.low_slices_psize,
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(unsigned long)mm->context.high_slices_psize);
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spin_unlock_irqrestore(&slice_convert_lock, flags);
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copro_flush_all_slbs(mm);
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}
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/*
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* Compute which slice addr is part of;
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* set *boundary_addr to the start or end boundary of that slice
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* (depending on 'end' parameter);
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* return boolean indicating if the slice is marked as available in the
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* 'available' slice_mark.
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*/
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static bool slice_scan_available(unsigned long addr,
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struct slice_mask available,
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int end,
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unsigned long *boundary_addr)
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{
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unsigned long slice;
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if (addr < SLICE_LOW_TOP) {
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slice = GET_LOW_SLICE_INDEX(addr);
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*boundary_addr = (slice + end) << SLICE_LOW_SHIFT;
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return !!(available.low_slices & (1u << slice));
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} else {
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slice = GET_HIGH_SLICE_INDEX(addr);
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*boundary_addr = (slice + end) ?
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((slice + end) << SLICE_HIGH_SHIFT) : SLICE_LOW_TOP;
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return !!test_bit(slice, available.high_slices);
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}
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}
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static unsigned long slice_find_area_bottomup(struct mm_struct *mm,
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unsigned long len,
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struct slice_mask available,
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int psize, unsigned long high_limit)
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{
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int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT);
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unsigned long addr, found, next_end;
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struct vm_unmapped_area_info info;
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info.flags = 0;
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info.length = len;
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info.align_mask = PAGE_MASK & ((1ul << pshift) - 1);
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info.align_offset = 0;
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addr = TASK_UNMAPPED_BASE;
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/*
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* Check till the allow max value for this mmap request
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*/
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while (addr < high_limit) {
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info.low_limit = addr;
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if (!slice_scan_available(addr, available, 1, &addr))
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continue;
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next_slice:
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/*
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* At this point [info.low_limit; addr) covers
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* available slices only and ends at a slice boundary.
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* Check if we need to reduce the range, or if we can
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* extend it to cover the next available slice.
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*/
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if (addr >= high_limit)
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addr = high_limit;
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else if (slice_scan_available(addr, available, 1, &next_end)) {
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addr = next_end;
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goto next_slice;
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}
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info.high_limit = addr;
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found = vm_unmapped_area(&info);
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if (!(found & ~PAGE_MASK))
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return found;
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}
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return -ENOMEM;
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}
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static unsigned long slice_find_area_topdown(struct mm_struct *mm,
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unsigned long len,
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struct slice_mask available,
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int psize, unsigned long high_limit)
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{
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int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT);
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unsigned long addr, found, prev;
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struct vm_unmapped_area_info info;
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info.flags = VM_UNMAPPED_AREA_TOPDOWN;
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info.length = len;
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info.align_mask = PAGE_MASK & ((1ul << pshift) - 1);
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info.align_offset = 0;
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addr = mm->mmap_base;
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/*
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* If we are trying to allocate above DEFAULT_MAP_WINDOW
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* Add the different to the mmap_base.
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* Only for that request for which high_limit is above
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* DEFAULT_MAP_WINDOW we should apply this.
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*/
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if (high_limit > DEFAULT_MAP_WINDOW)
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addr += mm->context.addr_limit - DEFAULT_MAP_WINDOW;
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while (addr > PAGE_SIZE) {
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info.high_limit = addr;
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if (!slice_scan_available(addr - 1, available, 0, &addr))
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continue;
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prev_slice:
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/*
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* At this point [addr; info.high_limit) covers
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* available slices only and starts at a slice boundary.
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* Check if we need to reduce the range, or if we can
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* extend it to cover the previous available slice.
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*/
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if (addr < PAGE_SIZE)
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addr = PAGE_SIZE;
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else if (slice_scan_available(addr - 1, available, 0, &prev)) {
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addr = prev;
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goto prev_slice;
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}
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info.low_limit = addr;
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found = vm_unmapped_area(&info);
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if (!(found & ~PAGE_MASK))
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return found;
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}
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/*
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* A failed mmap() very likely causes application failure,
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* so fall back to the bottom-up function here. This scenario
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* can happen with large stack limits and large mmap()
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* allocations.
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*/
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return slice_find_area_bottomup(mm, len, available, psize, high_limit);
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}
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static unsigned long slice_find_area(struct mm_struct *mm, unsigned long len,
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struct slice_mask mask, int psize,
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int topdown, unsigned long high_limit)
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{
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if (topdown)
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return slice_find_area_topdown(mm, len, mask, psize, high_limit);
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else
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return slice_find_area_bottomup(mm, len, mask, psize, high_limit);
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}
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static inline void slice_or_mask(struct slice_mask *dst, struct slice_mask *src)
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{
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DECLARE_BITMAP(result, SLICE_NUM_HIGH);
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dst->low_slices |= src->low_slices;
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bitmap_or(result, dst->high_slices, src->high_slices, SLICE_NUM_HIGH);
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bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
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}
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static inline void slice_andnot_mask(struct slice_mask *dst, struct slice_mask *src)
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{
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DECLARE_BITMAP(result, SLICE_NUM_HIGH);
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dst->low_slices &= ~src->low_slices;
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bitmap_andnot(result, dst->high_slices, src->high_slices, SLICE_NUM_HIGH);
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bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
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}
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#ifdef CONFIG_PPC_64K_PAGES
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#define MMU_PAGE_BASE MMU_PAGE_64K
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#else
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#define MMU_PAGE_BASE MMU_PAGE_4K
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#endif
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unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
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unsigned long flags, unsigned int psize,
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int topdown)
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{
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struct slice_mask mask;
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struct slice_mask good_mask;
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struct slice_mask potential_mask;
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struct slice_mask compat_mask;
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int fixed = (flags & MAP_FIXED);
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int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT);
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struct mm_struct *mm = current->mm;
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unsigned long newaddr;
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unsigned long high_limit;
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/*
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* Check if we need to expland slice area.
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*/
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if (unlikely(addr > mm->context.addr_limit &&
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mm->context.addr_limit != TASK_SIZE)) {
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mm->context.addr_limit = TASK_SIZE;
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on_each_cpu(slice_flush_segments, mm, 1);
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}
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/*
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* This mmap request can allocate upt to 512TB
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*/
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if (addr > DEFAULT_MAP_WINDOW)
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high_limit = mm->context.addr_limit;
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else
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high_limit = DEFAULT_MAP_WINDOW;
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/*
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* init different masks
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*/
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mask.low_slices = 0;
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bitmap_zero(mask.high_slices, SLICE_NUM_HIGH);
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/* silence stupid warning */;
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potential_mask.low_slices = 0;
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bitmap_zero(potential_mask.high_slices, SLICE_NUM_HIGH);
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compat_mask.low_slices = 0;
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bitmap_zero(compat_mask.high_slices, SLICE_NUM_HIGH);
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/* Sanity checks */
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BUG_ON(mm->task_size == 0);
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VM_BUG_ON(radix_enabled());
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slice_dbg("slice_get_unmapped_area(mm=%p, psize=%d...\n", mm, psize);
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slice_dbg(" addr=%lx, len=%lx, flags=%lx, topdown=%d\n",
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addr, len, flags, topdown);
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if (len > mm->task_size)
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return -ENOMEM;
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if (len & ((1ul << pshift) - 1))
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return -EINVAL;
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if (fixed && (addr & ((1ul << pshift) - 1)))
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return -EINVAL;
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if (fixed && addr > (mm->task_size - len))
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return -ENOMEM;
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/* If hint, make sure it matches our alignment restrictions */
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if (!fixed && addr) {
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addr = _ALIGN_UP(addr, 1ul << pshift);
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slice_dbg(" aligned addr=%lx\n", addr);
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/* Ignore hint if it's too large or overlaps a VMA */
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if (addr > mm->task_size - len ||
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!slice_area_is_free(mm, addr, len))
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addr = 0;
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}
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/* First make up a "good" mask of slices that have the right size
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* already
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*/
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slice_mask_for_size(mm, psize, &good_mask);
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slice_print_mask(" good_mask", good_mask);
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/*
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* Here "good" means slices that are already the right page size,
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* "compat" means slices that have a compatible page size (i.e.
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* 4k in a 64k pagesize kernel), and "free" means slices without
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* any VMAs.
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*
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* If MAP_FIXED:
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* check if fits in good | compat => OK
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* check if fits in good | compat | free => convert free
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* else bad
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* If have hint:
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* check if hint fits in good => OK
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* check if hint fits in good | free => convert free
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* Otherwise:
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* 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) {
|
|
slice_mask_for_size(mm, MMU_PAGE_4K, &compat_mask);
|
|
if (fixed)
|
|
slice_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 */
|
|
slice_range_to_mask(addr, len, &mask);
|
|
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(mm, 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, high_limit);
|
|
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
|
|
*/
|
|
slice_mask_for_free(mm, &potential_mask);
|
|
slice_or_mask(&potential_mask, &good_mask);
|
|
slice_print_mask(" potential", potential_mask);
|
|
|
|
if ((addr != 0 || fixed) && slice_check_fit(mm, 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, high_limit);
|
|
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, high_limit);
|
|
|
|
#ifdef CONFIG_PPC_64K_PAGES
|
|
if (addr == -ENOMEM && psize == MMU_PAGE_64K) {
|
|
/* retry the search with 4k-page slices included */
|
|
slice_or_mask(&potential_mask, &compat_mask);
|
|
addr = slice_find_area(mm, len, potential_mask,
|
|
psize, topdown, high_limit);
|
|
}
|
|
#endif
|
|
|
|
if (addr == -ENOMEM)
|
|
return -ENOMEM;
|
|
|
|
slice_range_to_mask(addr, len, &mask);
|
|
slice_dbg(" found potential area at 0x%lx\n", addr);
|
|
slice_print_mask(" mask", mask);
|
|
|
|
convert:
|
|
slice_andnot_mask(&mask, &good_mask);
|
|
slice_andnot_mask(&mask, &compat_mask);
|
|
if (mask.low_slices || !bitmap_empty(mask.high_slices, SLICE_NUM_HIGH)) {
|
|
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;
|
|
|
|
/*
|
|
* Radix doesn't use slice, but can get enabled along with MMU_SLICE
|
|
*/
|
|
if (radix_enabled()) {
|
|
#ifdef CONFIG_PPC_64K_PAGES
|
|
return MMU_PAGE_64K;
|
|
#else
|
|
return MMU_PAGE_4K;
|
|
#endif
|
|
}
|
|
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);
|
|
|
|
VM_BUG_ON(radix_enabled());
|
|
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",
|
|
(unsigned long)mm->context.low_slices_psize,
|
|
(unsigned long)mm->context.high_slices_psize);
|
|
|
|
bail:
|
|
spin_unlock_irqrestore(&slice_convert_lock, flags);
|
|
}
|
|
|
|
void slice_set_range_psize(struct mm_struct *mm, unsigned long start,
|
|
unsigned long len, unsigned int psize)
|
|
{
|
|
struct slice_mask mask;
|
|
|
|
VM_BUG_ON(radix_enabled());
|
|
|
|
slice_range_to_mask(start, len, &mask);
|
|
slice_convert(mm, mask, psize);
|
|
}
|
|
|
|
#ifdef CONFIG_HUGETLB_PAGE
|
|
/*
|
|
* 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;
|
|
|
|
if (radix_enabled())
|
|
return 0;
|
|
|
|
slice_range_to_mask(addr, len, &mask);
|
|
slice_mask_for_size(mm, psize, &available);
|
|
#ifdef CONFIG_PPC_64K_PAGES
|
|
/* We need to account for 4k slices too */
|
|
if (psize == MMU_PAGE_64K) {
|
|
struct slice_mask compat_mask;
|
|
slice_mask_for_size(mm, MMU_PAGE_4K, &compat_mask);
|
|
slice_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(mm, mask, available);
|
|
}
|
|
#endif
|