[PATCH 5/8] powerpc/mm: Call radix__arch_get_unmapped_area() from arch_get_unmapped_area()

Christophe Leroy
2021-11-22T08:49:24Z

Instead of setting mm->get_unmapped_area() to either
arch_get_unmapped_area() or radix__arch_get_unmapped_area(),
always set it to arch_get_unmapped_area() and call
radix__arch_get_unmapped_area() from there when radix is enabled.

To keep radix__arch_get_unmapped_area() static, move it to slice.c

Do the same with radix__arch_get_unmapped_area_topdown()

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/mm/book3s64/slice.c | 104 ++++++++++++++++++++++++++
arch/powerpc/mm/mmap.c | 123 -------------------------------
2 files changed, 104 insertions(+), 123 deletions(-)

diff --git a/arch/powerpc/mm/book3s64/slice.c b/arch/powerpc/mm/book3s64/slice.c
index 62848c5fa2d6..8327a43d29cb 100644
--- a/arch/powerpc/mm/book3s64/slice.c
+++ b/arch/powerpc/mm/book3s64/slice.c
@@ -639,12 +639,113 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
}
EXPORT_SYMBOL_GPL(slice_get_unmapped_area);

+/*
+ * Same function as generic code used only for radix, because we don't need to overload
+ * the generic one. But we will have to duplicate, because hash select
+ * HAVE_ARCH_UNMAPPED_AREA
+ */
+static unsigned long
+radix__arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len,
+ unsigned long pgoff, unsigned long flags)
+{
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ int fixed = (flags & MAP_FIXED);
+ unsigned long high_limit;
+ struct vm_unmapped_area_info info;
+
+ 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 (fixed) {
+ if (addr > high_limit - len)
+ return -ENOMEM;
+ return addr;
+ }
+
+ if (addr) {
+ addr = PAGE_ALIGN(addr);
+ vma = find_vma(mm, addr);
+ if (high_limit - len >= addr && addr >= mmap_min_addr &&
+ (!vma || addr + len <= vm_start_gap(vma)))
+ return addr;
+ }
+
+ info.flags = 0;
+ info.length = len;
+ info.low_limit = mm->mmap_base;
+ info.high_limit = high_limit;
+ info.align_mask = 0;
+
+ return vm_unmapped_area(&info);
+}
+
+static unsigned long
+radix__arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
+ const unsigned long len, const unsigned long pgoff,
+ const unsigned long flags)
+{
+ struct vm_area_struct *vma;
+ struct mm_struct *mm = current->mm;
+ unsigned long addr = addr0;
+ int fixed = (flags & MAP_FIXED);
+ unsigned long high_limit;
+ struct vm_unmapped_area_info info;
+
+ 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 (fixed) {
+ if (addr > high_limit - len)
+ return -ENOMEM;
+ return addr;
+ }
+
+ if (addr) {
+ addr = PAGE_ALIGN(addr);
+ vma = find_vma(mm, addr);
+ if (high_limit - len >= addr && addr >= mmap_min_addr &&
+ (!vma || addr + len <= vm_start_gap(vma)))
+ return addr;
+ }
+
+ info.flags = VM_UNMAPPED_AREA_TOPDOWN;
+ info.length = len;
+ info.low_limit = max(PAGE_SIZE, mmap_min_addr);
+ info.high_limit = mm->mmap_base + (high_limit - DEFAULT_MAP_WINDOW);
+ info.align_mask = 0;
+
+ addr = vm_unmapped_area(&info);
+ if (!(addr & ~PAGE_MASK))
+ return addr;
+ VM_BUG_ON(addr != -ENOMEM);
+
+ /*
+ * 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 radix__arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
+}
+
unsigned long arch_get_unmapped_area(struct file *filp,
unsigned long addr,
unsigned long len,
unsigned long pgoff,
unsigned long flags)
{
+ if (radix_enabled())
+ return radix__arch_get_unmapped_area(filp, addr, len, pgoff, flags);
+
return slice_get_unmapped_area(addr, len, flags,
mm_ctx_user_psize(&current->mm->context), 0);
}
@@ -655,6 +756,9 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp,
const unsigned long pgoff,
const unsigned long flags)
{
+ if (radix_enabled())
+ return radix__arch_get_unmapped_area_topdown(filp, addr0, len, pgoff, flags);
+
return slice_get_unmapped_area(addr0, len, flags,
mm_ctx_user_psize(&current->mm->context), 1);
}
diff --git a/arch/powerpc/mm/mmap.c b/arch/powerpc/mm/mmap.c
index ae683fdc716c..5972d619d274 100644
--- a/arch/powerpc/mm/mmap.c
+++ b/arch/powerpc/mm/mmap.c
@@ -80,126 +80,6 @@ static inline unsigned long mmap_base(unsigned long rnd,
return PAGE_ALIGN(DEFAULT_MAP_WINDOW - gap - rnd);
}

-#ifdef CONFIG_PPC_RADIX_MMU
-/*
- * Same function as generic code used only for radix, because we don't need to overload
- * the generic one. But we will have to duplicate, because hash select
- * HAVE_ARCH_UNMAPPED_AREA
- */
-static unsigned long
-radix__arch_get_unmapped_area(struct file *filp, unsigned long addr,
- unsigned long len, unsigned long pgoff,
- unsigned long flags)
-{
- struct mm_struct *mm = current->mm;
- struct vm_area_struct *vma;
- int fixed = (flags & MAP_FIXED);
- unsigned long high_limit;
- struct vm_unmapped_area_info info;
-
- 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 (fixed) {
- if (addr > high_limit - len)
- return -ENOMEM;
- return addr;
- }
-
- if (addr) {
- addr = PAGE_ALIGN(addr);
- vma = find_vma(mm, addr);
- if (high_limit - len >= addr && addr >= mmap_min_addr &&
- (!vma || addr + len <= vm_start_gap(vma)))
- return addr;
- }
-
- info.flags = 0;
- info.length = len;
- info.low_limit = mm->mmap_base;
- info.high_limit = high_limit;
- info.align_mask = 0;
-
- return vm_unmapped_area(&info);
-}
-
-static unsigned long
-radix__arch_get_unmapped_area_topdown(struct file *filp,
- const unsigned long addr0,
- const unsigned long len,
- const unsigned long pgoff,
- const unsigned long flags)
-{
- struct vm_area_struct *vma;
- struct mm_struct *mm = current->mm;
- unsigned long addr = addr0;
- int fixed = (flags & MAP_FIXED);
- unsigned long high_limit;
- struct vm_unmapped_area_info info;
-
- 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 (fixed) {
- if (addr > high_limit - len)
- return -ENOMEM;
- return addr;
- }
-
- if (addr) {
- addr = PAGE_ALIGN(addr);
- vma = find_vma(mm, addr);
- if (high_limit - len >= addr && addr >= mmap_min_addr &&
- (!vma || addr + len <= vm_start_gap(vma)))
- return addr;
- }
-
- info.flags = VM_UNMAPPED_AREA_TOPDOWN;
- info.length = len;
- info.low_limit = max(PAGE_SIZE, mmap_min_addr);
- info.high_limit = mm->mmap_base + (high_limit - DEFAULT_MAP_WINDOW);
- info.align_mask = 0;
-
- addr = vm_unmapped_area(&info);
- if (!(addr & ~PAGE_MASK))
- return addr;
- VM_BUG_ON(addr != -ENOMEM);
-
- /*
- * 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 radix__arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
-}
-
-static void radix__arch_pick_mmap_layout(struct mm_struct *mm,
- unsigned long random_factor,
- struct rlimit *rlim_stack)
-{
- if (mmap_is_legacy(rlim_stack)) {
- mm->mmap_base = TASK_UNMAPPED_BASE;
- mm->get_unmapped_area = radix__arch_get_unmapped_area;
- } else {
- mm->mmap_base = mmap_base(random_factor, rlim_stack);
- mm->get_unmapped_area = radix__arch_get_unmapped_area_topdown;
- }
-}
-#else
-/* dummy */
-extern void radix__arch_pick_mmap_layout(struct mm_struct *mm,
- unsigned long random_factor,
- struct rlimit *rlim_stack);
-#endif
/*
* This function, called very early during the creation of a new
* process VM image, sets up which VM layout function to use:
@@ -211,9 +91,6 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
if (current->flags & PF_RANDOMIZE)
random_factor = arch_mmap_rnd();

- if (radix_enabled())
- return radix__arch_pick_mmap_layout(mm, random_factor,
- rlim_stack);
/*
* Fall back to the standard layout if the personality
* bit is set, or if the expected stack growth is unlimited:
--
2.33.1