v4.19.13 snapshot.
diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c
new file mode 100644
index 0000000..4f213ba
--- /dev/null
+++ b/arch/powerpc/mm/slice.c
@@ -0,0 +1,821 @@
+/*
+ * 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 <linux/hugetlb.h>
+#include <asm/mman.h>
+#include <asm/mmu.h>
+#include <asm/copro.h>
+#include <asm/hugetlb.h>
+#include <asm/mmu_context.h>
+
+static DEFINE_SPINLOCK(slice_convert_lock);
+
+#ifdef DEBUG
+int _slice_debug = 1;
+
+static void slice_print_mask(const char *label, const struct slice_mask *mask)
+{
+ if (!_slice_debug)
+ return;
+ pr_devel("%s low_slice: %*pbl\n", label,
+ (int)SLICE_NUM_LOW, &mask->low_slices);
+ pr_devel("%s high_slice: %*pbl\n", label,
+ (int)SLICE_NUM_HIGH, mask->high_slices);
+}
+
+#define slice_dbg(fmt...) do { if (_slice_debug) pr_devel(fmt); } while (0)
+
+#else
+
+static void slice_print_mask(const char *label, const struct slice_mask *mask) {}
+#define slice_dbg(fmt...)
+
+#endif
+
+static inline bool slice_addr_is_low(unsigned long addr)
+{
+ u64 tmp = (u64)addr;
+
+ return tmp < SLICE_LOW_TOP;
+}
+
+static void slice_range_to_mask(unsigned long start, unsigned long len,
+ struct slice_mask *ret)
+{
+ unsigned long end = start + len - 1;
+
+ ret->low_slices = 0;
+ if (SLICE_NUM_HIGH)
+ bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
+
+ if (slice_addr_is_low(start)) {
+ unsigned long mend = min(end,
+ (unsigned long)(SLICE_LOW_TOP - 1));
+
+ ret->low_slices = (1u << (GET_LOW_SLICE_INDEX(mend) + 1))
+ - (1u << GET_LOW_SLICE_INDEX(start));
+ }
+
+ if (SLICE_NUM_HIGH && !slice_addr_is_low(end)) {
+ unsigned long start_index = GET_HIGH_SLICE_INDEX(start);
+ unsigned long align_end = ALIGN(end, (1UL << SLICE_HIGH_SHIFT));
+ unsigned long count = GET_HIGH_SLICE_INDEX(align_end) - start_index;
+
+ bitmap_set(ret->high_slices, start_index, count);
+ }
+}
+
+static int slice_area_is_free(struct mm_struct *mm, unsigned long addr,
+ unsigned long len)
+{
+ struct vm_area_struct *vma;
+
+ if ((mm->context.slb_addr_limit - len) < addr)
+ return 0;
+ vma = find_vma(mm, addr);
+ return (!vma || (addr + len) <= vm_start_gap(vma));
+}
+
+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);
+
+#ifdef CONFIG_PPC64
+ /* 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;
+#endif
+
+ return !slice_area_is_free(mm, start, end - start);
+}
+
+static void slice_mask_for_free(struct mm_struct *mm, struct slice_mask *ret,
+ unsigned long high_limit)
+{
+ unsigned long i;
+
+ ret->low_slices = 0;
+ if (SLICE_NUM_HIGH)
+ bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
+
+ for (i = 0; i < SLICE_NUM_LOW; i++)
+ if (!slice_low_has_vma(mm, i))
+ ret->low_slices |= 1u << i;
+
+ if (slice_addr_is_low(high_limit - 1))
+ return;
+
+ for (i = 0; i < GET_HIGH_SLICE_INDEX(high_limit); i++)
+ if (!slice_high_has_vma(mm, i))
+ __set_bit(i, ret->high_slices);
+}
+
+#ifdef CONFIG_PPC_BOOK3S_64
+static struct slice_mask *slice_mask_for_size(struct mm_struct *mm, int psize)
+{
+#ifdef CONFIG_PPC_64K_PAGES
+ if (psize == MMU_PAGE_64K)
+ return &mm->context.mask_64k;
+#endif
+ if (psize == MMU_PAGE_4K)
+ return &mm->context.mask_4k;
+#ifdef CONFIG_HUGETLB_PAGE
+ if (psize == MMU_PAGE_16M)
+ return &mm->context.mask_16m;
+ if (psize == MMU_PAGE_16G)
+ return &mm->context.mask_16g;
+#endif
+ BUG();
+}
+#elif defined(CONFIG_PPC_8xx)
+static struct slice_mask *slice_mask_for_size(struct mm_struct *mm, int psize)
+{
+ if (psize == mmu_virtual_psize)
+ return &mm->context.mask_base_psize;
+#ifdef CONFIG_HUGETLB_PAGE
+ if (psize == MMU_PAGE_512K)
+ return &mm->context.mask_512k;
+ if (psize == MMU_PAGE_8M)
+ return &mm->context.mask_8m;
+#endif
+ BUG();
+}
+#else
+#error "Must define the slice masks for page sizes supported by the platform"
+#endif
+
+static bool slice_check_range_fits(struct mm_struct *mm,
+ const struct slice_mask *available,
+ unsigned long start, unsigned long len)
+{
+ unsigned long end = start + len - 1;
+ u64 low_slices = 0;
+
+ if (slice_addr_is_low(start)) {
+ unsigned long mend = min(end,
+ (unsigned long)(SLICE_LOW_TOP - 1));
+
+ low_slices = (1u << (GET_LOW_SLICE_INDEX(mend) + 1))
+ - (1u << GET_LOW_SLICE_INDEX(start));
+ }
+ if ((low_slices & available->low_slices) != low_slices)
+ return false;
+
+ if (SLICE_NUM_HIGH && !slice_addr_is_low(end)) {
+ unsigned long start_index = GET_HIGH_SLICE_INDEX(start);
+ unsigned long align_end = ALIGN(end, (1UL << SLICE_HIGH_SHIFT));
+ unsigned long count = GET_HIGH_SLICE_INDEX(align_end) - start_index;
+ unsigned long i;
+
+ for (i = start_index; i < start_index + count; i++) {
+ if (!test_bit(i, available->high_slices))
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static void slice_flush_segments(void *parm)
+{
+#ifdef CONFIG_PPC64
+ struct mm_struct *mm = parm;
+ unsigned long flags;
+
+ if (mm != current->active_mm)
+ return;
+
+ copy_mm_to_paca(current->active_mm);
+
+ local_irq_save(flags);
+ slb_flush_and_rebolt();
+ local_irq_restore(flags);
+#endif
+}
+
+static void slice_convert(struct mm_struct *mm,
+ const struct slice_mask *mask, int psize)
+{
+ int index, mask_index;
+ /* Write the new slice psize bits */
+ unsigned char *hpsizes, *lpsizes;
+ struct slice_mask *psize_mask, *old_mask;
+ unsigned long i, flags;
+ int old_psize;
+
+ slice_dbg("slice_convert(mm=%p, psize=%d)\n", mm, psize);
+ slice_print_mask(" mask", mask);
+
+ psize_mask = slice_mask_for_size(mm, psize);
+
+ /* 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)))
+ continue;
+
+ mask_index = i & 0x1;
+ index = i >> 1;
+
+ /* Update the slice_mask */
+ old_psize = (lpsizes[index] >> (mask_index * 4)) & 0xf;
+ old_mask = slice_mask_for_size(mm, old_psize);
+ old_mask->low_slices &= ~(1u << i);
+ psize_mask->low_slices |= 1u << i;
+
+ /* Update the sizes array */
+ lpsizes[index] = (lpsizes[index] & ~(0xf << (mask_index * 4))) |
+ (((unsigned long)psize) << (mask_index * 4));
+ }
+
+ hpsizes = mm->context.high_slices_psize;
+ for (i = 0; i < GET_HIGH_SLICE_INDEX(mm->context.slb_addr_limit); i++) {
+ if (!test_bit(i, mask->high_slices))
+ continue;
+
+ mask_index = i & 0x1;
+ index = i >> 1;
+
+ /* Update the slice_mask */
+ old_psize = (hpsizes[index] >> (mask_index * 4)) & 0xf;
+ old_mask = slice_mask_for_size(mm, old_psize);
+ __clear_bit(i, old_mask->high_slices);
+ __set_bit(i, psize_mask->high_slices);
+
+ /* Update the sizes array */
+ 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);
+
+ spin_unlock_irqrestore(&slice_convert_lock, flags);
+
+ copro_flush_all_slbs(mm);
+}
+
+/*
+ * 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,
+ const struct slice_mask *available,
+ int end, unsigned long *boundary_addr)
+{
+ unsigned long slice;
+ if (slice_addr_is_low(addr)) {
+ 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 !!test_bit(slice, available->high_slices);
+ }
+}
+
+static unsigned long slice_find_area_bottomup(struct mm_struct *mm,
+ unsigned long len,
+ const struct slice_mask *available,
+ int psize, unsigned long high_limit)
+{
+ 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;
+ /*
+ * Check till the allow max value for this mmap request
+ */
+ while (addr < high_limit) {
+ 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 >= high_limit)
+ addr = high_limit;
+ 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,
+ const struct slice_mask *available,
+ int psize, unsigned long high_limit)
+{
+ 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;
+ /*
+ * If we are trying to allocate above DEFAULT_MAP_WINDOW
+ * Add the different to the mmap_base.
+ * Only for that request for which high_limit is above
+ * DEFAULT_MAP_WINDOW we should apply this.
+ */
+ if (high_limit > DEFAULT_MAP_WINDOW)
+ addr += mm->context.slb_addr_limit - DEFAULT_MAP_WINDOW;
+
+ 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, high_limit);
+}
+
+
+static unsigned long slice_find_area(struct mm_struct *mm, unsigned long len,
+ const struct slice_mask *mask, int psize,
+ int topdown, unsigned long high_limit)
+{
+ if (topdown)
+ return slice_find_area_topdown(mm, len, mask, psize, high_limit);
+ else
+ return slice_find_area_bottomup(mm, len, mask, psize, high_limit);
+}
+
+static inline void slice_copy_mask(struct slice_mask *dst,
+ const struct slice_mask *src)
+{
+ dst->low_slices = src->low_slices;
+ if (!SLICE_NUM_HIGH)
+ return;
+ bitmap_copy(dst->high_slices, src->high_slices, SLICE_NUM_HIGH);
+}
+
+static inline void slice_or_mask(struct slice_mask *dst,
+ const struct slice_mask *src1,
+ const struct slice_mask *src2)
+{
+ dst->low_slices = src1->low_slices | src2->low_slices;
+ if (!SLICE_NUM_HIGH)
+ return;
+ bitmap_or(dst->high_slices, src1->high_slices, src2->high_slices, SLICE_NUM_HIGH);
+}
+
+static inline void slice_andnot_mask(struct slice_mask *dst,
+ const struct slice_mask *src1,
+ const struct slice_mask *src2)
+{
+ dst->low_slices = src1->low_slices & ~src2->low_slices;
+ if (!SLICE_NUM_HIGH)
+ return;
+ bitmap_andnot(dst->high_slices, src1->high_slices, src2->high_slices, SLICE_NUM_HIGH);
+}
+
+#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 good_mask;
+ struct slice_mask potential_mask;
+ const struct slice_mask *maskp;
+ const struct slice_mask *compat_maskp = NULL;
+ int fixed = (flags & MAP_FIXED);
+ int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT);
+ unsigned long page_size = 1UL << pshift;
+ struct mm_struct *mm = current->mm;
+ unsigned long newaddr;
+ unsigned long high_limit;
+
+ high_limit = DEFAULT_MAP_WINDOW;
+ if (addr >= high_limit || (fixed && (addr + len > high_limit)))
+ high_limit = TASK_SIZE;
+
+ if (len > high_limit)
+ return -ENOMEM;
+ if (len & (page_size - 1))
+ return -EINVAL;
+ if (fixed) {
+ if (addr & (page_size - 1))
+ return -EINVAL;
+ if (addr > high_limit - len)
+ return -ENOMEM;
+ }
+
+ if (high_limit > mm->context.slb_addr_limit) {
+ /*
+ * Increasing the slb_addr_limit does not require
+ * slice mask cache to be recalculated because it should
+ * be already initialised beyond the old address limit.
+ */
+ mm->context.slb_addr_limit = high_limit;
+
+ on_each_cpu(slice_flush_segments, mm, 1);
+ }
+
+ /* Sanity checks */
+ BUG_ON(mm->task_size == 0);
+ BUG_ON(mm->context.slb_addr_limit == 0);
+ VM_BUG_ON(radix_enabled());
+
+ 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 hint, make sure it matches our alignment restrictions */
+ if (!fixed && addr) {
+ addr = _ALIGN_UP(addr, page_size);
+ slice_dbg(" aligned addr=%lx\n", addr);
+ /* Ignore hint if it's too large or overlaps a VMA */
+ if (addr > high_limit - len ||
+ !slice_area_is_free(mm, addr, len))
+ addr = 0;
+ }
+
+ /* First make up a "good" mask of slices that have the right size
+ * already
+ */
+ maskp = slice_mask_for_size(mm, psize);
+
+ /*
+ * 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.
+ */
+
+ /*
+ * If we support combo pages, we can allow 64k pages in 4k slices
+ * The mask copies could be avoided in most cases here if we had
+ * a pointer to good mask for the next code to use.
+ */
+ if (IS_ENABLED(CONFIG_PPC_64K_PAGES) && psize == MMU_PAGE_64K) {
+ compat_maskp = slice_mask_for_size(mm, MMU_PAGE_4K);
+ if (fixed)
+ slice_or_mask(&good_mask, maskp, compat_maskp);
+ else
+ slice_copy_mask(&good_mask, maskp);
+ } else {
+ slice_copy_mask(&good_mask, maskp);
+ }
+
+ slice_print_mask(" good_mask", &good_mask);
+ if (compat_maskp)
+ slice_print_mask(" compat_mask", compat_maskp);
+
+ /* First check hint if it's valid or if we have MAP_FIXED */
+ if (addr != 0 || fixed) {
+ /* Check if we fit in the good mask. If we do, we just return,
+ * nothing else to do
+ */
+ if (slice_check_range_fits(mm, &good_mask, addr, len)) {
+ slice_dbg(" fits good !\n");
+ newaddr = addr;
+ goto 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);
+ goto return_addr;
+ }
+ }
+ /*
+ * 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, high_limit);
+ slice_or_mask(&potential_mask, &potential_mask, &good_mask);
+ slice_print_mask(" potential", &potential_mask);
+
+ if (addr != 0 || fixed) {
+ if (slice_check_range_fits(mm, &potential_mask, addr, len)) {
+ slice_dbg(" fits potential !\n");
+ newaddr = addr;
+ 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) {
+ newaddr = slice_find_area(mm, len, &good_mask,
+ psize, topdown, high_limit);
+ if (newaddr != -ENOMEM) {
+ slice_dbg(" found area at 0x%lx\n", newaddr);
+ goto return_addr;
+ }
+ }
+
+ /* Now let's see if we can find something in the existing slices
+ * for that size plus free slices
+ */
+ newaddr = slice_find_area(mm, len, &potential_mask,
+ psize, topdown, high_limit);
+
+#ifdef CONFIG_PPC_64K_PAGES
+ if (newaddr == -ENOMEM && psize == MMU_PAGE_64K) {
+ /* retry the search with 4k-page slices included */
+ slice_or_mask(&potential_mask, &potential_mask, compat_maskp);
+ newaddr = slice_find_area(mm, len, &potential_mask,
+ psize, topdown, high_limit);
+ }
+#endif
+
+ if (newaddr == -ENOMEM)
+ return -ENOMEM;
+
+ slice_range_to_mask(newaddr, len, &potential_mask);
+ slice_dbg(" found potential area at 0x%lx\n", newaddr);
+ slice_print_mask(" mask", &potential_mask);
+
+ convert:
+ /*
+ * Try to allocate the context before we do slice convert
+ * so that we handle the context allocation failure gracefully.
+ */
+ if (need_extra_context(mm, newaddr)) {
+ if (alloc_extended_context(mm, newaddr) < 0)
+ return -ENOMEM;
+ }
+
+ slice_andnot_mask(&potential_mask, &potential_mask, &good_mask);
+ if (compat_maskp && !fixed)
+ slice_andnot_mask(&potential_mask, &potential_mask, compat_maskp);
+ if (potential_mask.low_slices ||
+ (SLICE_NUM_HIGH &&
+ !bitmap_empty(potential_mask.high_slices, SLICE_NUM_HIGH))) {
+ slice_convert(mm, &potential_mask, psize);
+ if (psize > MMU_PAGE_BASE)
+ on_each_cpu(slice_flush_segments, mm, 1);
+ }
+ return newaddr;
+
+return_addr:
+ if (need_extra_context(mm, newaddr)) {
+ if (alloc_extended_context(mm, newaddr) < 0)
+ return -ENOMEM;
+ }
+ return newaddr;
+}
+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 *psizes;
+ int index, mask_index;
+
+ VM_BUG_ON(radix_enabled());
+
+ if (slice_addr_is_low(addr)) {
+ psizes = mm->context.low_slices_psize;
+ index = GET_LOW_SLICE_INDEX(addr);
+ } else {
+ psizes = mm->context.high_slices_psize;
+ index = GET_HIGH_SLICE_INDEX(addr);
+ }
+ mask_index = index & 0x1;
+ return (psizes[index >> 1] >> (mask_index * 4)) & 0xf;
+}
+EXPORT_SYMBOL_GPL(get_slice_psize);
+
+void slice_init_new_context_exec(struct mm_struct *mm)
+{
+ unsigned char *hpsizes, *lpsizes;
+ struct slice_mask *mask;
+ unsigned int psize = mmu_virtual_psize;
+
+ slice_dbg("slice_init_new_context_exec(mm=%p)\n", mm);
+
+ /*
+ * In the case of exec, use the default limit. In the
+ * case of fork it is just inherited from the mm being
+ * duplicated.
+ */
+#ifdef CONFIG_PPC64
+ mm->context.slb_addr_limit = DEFAULT_MAP_WINDOW_USER64;
+#else
+ mm->context.slb_addr_limit = DEFAULT_MAP_WINDOW;
+#endif
+
+ mm->context.user_psize = psize;
+
+ /*
+ * Set all slice psizes to the default.
+ */
+ lpsizes = mm->context.low_slices_psize;
+ memset(lpsizes, (psize << 4) | psize, SLICE_NUM_LOW >> 1);
+
+ hpsizes = mm->context.high_slices_psize;
+ memset(hpsizes, (psize << 4) | psize, SLICE_NUM_HIGH >> 1);
+
+ /*
+ * Slice mask cache starts zeroed, fill the default size cache.
+ */
+ mask = slice_mask_for_size(mm, psize);
+ mask->low_slices = ~0UL;
+ if (SLICE_NUM_HIGH)
+ bitmap_fill(mask->high_slices, SLICE_NUM_HIGH);
+}
+
+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 slice_is_hugepage_only_range(struct mm_struct *mm, unsigned long addr,
+ unsigned long len)
+{
+ const struct slice_mask *maskp;
+ unsigned int psize = mm->context.user_psize;
+
+ VM_BUG_ON(radix_enabled());
+
+ maskp = slice_mask_for_size(mm, psize);
+#ifdef CONFIG_PPC_64K_PAGES
+ /* We need to account for 4k slices too */
+ if (psize == MMU_PAGE_64K) {
+ const struct slice_mask *compat_maskp;
+ struct slice_mask available;
+
+ compat_maskp = slice_mask_for_size(mm, MMU_PAGE_4K);
+ slice_or_mask(&available, maskp, compat_maskp);
+ return !slice_check_range_fits(mm, &available, addr, len);
+ }
+#endif
+
+ return !slice_check_range_fits(mm, maskp, addr, len);
+}
+#endif