Update the powerpc slice_get_unmapped_area function to make use of
vm_unmapped_area() instead of implementing a brute force search.
Signed-off-by: Michel Lespinasse <wal...@google.com>
---
arch/powerpc/mm/slice.c | 128 +++++++++++++++++++++++++++++-----------------
1 files changed, 81 insertions(+), 47 deletions(-)
diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c
index 999a74f25ebe..048346b7eed5 100644
--- a/arch/powerpc/mm/slice.c
+++ b/arch/powerpc/mm/slice.c
@@ -242,31 +242,51 @@ static unsigned long slice_find_area_bottomup(struct
mm_struct *mm,
struct slice_mask available,
int psize)
{
- struct vm_area_struct *vma;
- unsigned long addr;
- struct slice_mask mask;
int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT);
+ unsigned long addr, found, slice;
+ struct vm_unmapped_area_info info;
- addr = TASK_UNMAPPED_BASE;
+ info.flags = 0;
+ info.length = len;
+ info.align_mask = PAGE_MASK & ((1ul << pshift) - 1);
+ info.align_offset = 0;
- for (;;) {
- addr = _ALIGN_UP(addr, 1ul << pshift);
- if ((TASK_SIZE - len) < addr)
- break;
- vma = find_vma(mm, addr);
- BUG_ON(vma && (addr >= vma->vm_end));
+ addr = TASK_UNMAPPED_BASE;
+ while (addr < TASK_SIZE) {
+ info.low_limit = addr;
+ if (addr < SLICE_LOW_TOP) {
+ slice = GET_LOW_SLICE_INDEX(addr);
+ addr = (slice + 1) << SLICE_LOW_SHIFT;
+ if (!(available.low_slices & (1u << slice)))
+ continue;
+ } else {
+ slice = GET_HIGH_SLICE_INDEX(addr);
+ addr = (slice + 1) << SLICE_HIGH_SHIFT;
+ if (!(available.high_slices & (1u << slice)))
+ continue;
+ }
- mask = slice_range_to_mask(addr, len);
- if (!slice_check_fit(mask, available)) {
- if (addr < SLICE_LOW_TOP)
- addr = _ALIGN_UP(addr + 1, 1ul <<
SLICE_LOW_SHIFT);
- else
- addr = _ALIGN_UP(addr + 1, 1ul <<
SLICE_HIGH_SHIFT);
- continue;
+ next_slice:
+ if (addr >= TASK_SIZE)
+ addr = TASK_SIZE;
+ else if (addr < SLICE_LOW_TOP) {
+ slice = GET_LOW_SLICE_INDEX(addr);
+ if (available.low_slices & (1u << slice)) {
+ addr = (slice + 1) << SLICE_LOW_SHIFT;
+ goto next_slice;
+ }
+ } else {
+ slice = GET_HIGH_SLICE_INDEX(addr);
+ if (available.high_slices & (1u << slice)) {
+ addr = (slice + 1) << SLICE_HIGH_SHIFT;
+ goto next_slice;
+ }
}
- if (!vma || addr + len <= vma->vm_start)
- return addr;
- addr = vma->vm_end;
+ info.high_limit = addr;
+
+ found = vm_unmapped_area(&info);
+ if (!(found & ~PAGE_MASK))
+ return found;
}
return -ENOMEM;
@@ -277,39 +297,53 @@ static unsigned long slice_find_area_topdown(struct
mm_struct *mm,
struct slice_mask available,
int psize)
{
- struct vm_area_struct *vma;
- unsigned long addr;
- struct slice_mask mask;
int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT);
+ unsigned long addr, found, slice;
+ struct vm_unmapped_area_info info;
- addr = mm->mmap_base;
- while (addr > len) {
- /* Go down by chunk size */
- addr = _ALIGN_DOWN(addr - len, 1ul << pshift);
+ info.flags = VM_UNMAPPED_AREA_TOPDOWN;
+ info.length = len;
+ info.align_mask = PAGE_MASK & ((1ul << pshift) - 1);
+ info.align_offset = 0;
- /* Check for hit with different page size */
- mask = slice_range_to_mask(addr, len);
- if (!slice_check_fit(mask, available)) {
- if (addr < SLICE_LOW_TOP)
- addr = _ALIGN_DOWN(addr, 1ul <<
SLICE_LOW_SHIFT);
- else if (addr < (1ul << SLICE_HIGH_SHIFT))
- addr = SLICE_LOW_TOP;
- else
- addr = _ALIGN_DOWN(addr, 1ul <<
SLICE_HIGH_SHIFT);
- continue;
+ addr = mm->mmap_base;
+ while (addr > PAGE_SIZE) {
+ info.high_limit = addr;
+ if (addr < SLICE_LOW_TOP) {
+ slice = GET_LOW_SLICE_INDEX(addr - 1);
+ addr = slice << SLICE_LOW_SHIFT;
+ if (!(available.low_slices & (1u << slice)))
+ continue;
+ } else {
+ slice = GET_HIGH_SLICE_INDEX(addr - 1);
+ addr = slice ? (slice << SLICE_HIGH_SHIFT) :
+ SLICE_LOW_TOP;
+ if (!(available.high_slices & (1u << slice)))
+ continue;
}
- /*
- * Lookup failure means no vma is above this address,
- * else if new region fits below vma->vm_start,
- * return with success:
- */
- vma = find_vma(mm, addr);
- if (!vma || (addr + len) <= vma->vm_start)
- return addr;
+ next_slice:
+ if (addr < PAGE_SIZE)
+ addr = PAGE_SIZE;
+ else if (addr < SLICE_LOW_TOP) {
+ slice = GET_LOW_SLICE_INDEX(addr - 1);
+ if (available.low_slices & (1u << slice)) {
+ addr = slice << SLICE_LOW_SHIFT;
+ goto next_slice;
+ }
+ } else {
+ slice = GET_HIGH_SLICE_INDEX(addr - 1);
+ if (available.high_slices & (1u << slice)) {
+ addr = slice ? (slice << SLICE_HIGH_SHIFT) :
+ SLICE_LOW_TOP;
+ goto next_slice;
+ }
+ }
+ info.low_limit = addr;
- /* try just below the current vma->vm_start */
- addr = vma->vm_start;
+ found = vm_unmapped_area(&info);
+ if (!(found & ~PAGE_MASK))
+ return found;
}
/*
--
1.7.7.3
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