Introduce x86 arch_mmap_hint() and define HAVE_ARCH_MMAP_HINT.
This is a preparatory patch, no functional change is introduced.
Signed-off-by: Kalesh Singh <kaleshsi...@google.com>
---
arch/x86/include/asm/pgtable_64.h | 1 +
arch/x86/kernel/sys_x86_64.c | 49 ++++++++++++++++++-------------
include/linux/sched/mm.h | 4 +++
3 files changed, 33 insertions(+), 21 deletions(-)
diff --git a/arch/x86/include/asm/pgtable_64.h
b/arch/x86/include/asm/pgtable_64.h
index d1426b64c1b9..4472fd0040c3 100644
--- a/arch/x86/include/asm/pgtable_64.h
+++ b/arch/x86/include/asm/pgtable_64.h
@@ -245,6 +245,7 @@ extern void cleanup_highmap(void);
#define HAVE_ARCH_UNMAPPED_AREA
#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
+#define HAVE_ARCH_MMAP_HINT
#define PAGE_AGP PAGE_KERNEL_NOCACHE
#define HAVE_PAGE_AGP 1
diff --git a/arch/x86/kernel/sys_x86_64.c b/arch/x86/kernel/sys_x86_64.c
index 776ae6fa7f2d..95a39ef915b7 100644
--- a/arch/x86/kernel/sys_x86_64.c
+++ b/arch/x86/kernel/sys_x86_64.c
@@ -123,12 +123,32 @@ static inline unsigned long
stack_guard_placement(vm_flags_t vm_flags)
return 0;
}
+unsigned long arch_mmap_hint(struct file *filp, unsigned long addr,
+ unsigned long len, unsigned long pgoff,
+ unsigned long flags)
+{
+ unsigned long begin, end;
+
+ if (!addr)
+ return 0;
+
+ find_start_end(addr, flags, &begin, &end);
+
+ addr = PAGE_ALIGN(addr);
+
+ if (!mmap_address_hint_valid(addr, len))
+ return 0;
+
+ if (len > end)
+ return 0;
+
+ return generic_mmap_hint(filp, addr, len, pgoff, flags);
+}
+
unsigned long
arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long
len,
unsigned long pgoff, unsigned long flags, vm_flags_t
vm_flags)
{
- struct mm_struct *mm = current->mm;
- struct vm_area_struct *vma;
struct vm_unmapped_area_info info = {};
unsigned long begin, end;
@@ -140,13 +160,9 @@ arch_get_unmapped_area(struct file *filp, unsigned long
addr, unsigned long len,
if (len > end)
return -ENOMEM;
- if (addr) {
- addr = PAGE_ALIGN(addr);
- vma = find_vma(mm, addr);
- if (end - len >= addr &&
- (!vma || addr + len <= vm_start_gap(vma)))
- return addr;
- }
+ addr = arch_mmap_hint(filp, addr, len, pgoff, flags);
+ if (addr)
+ return addr;
info.length = len;
info.low_limit = begin;
@@ -168,8 +184,6 @@ arch_get_unmapped_area_topdown(struct file *filp, unsigned
long addr0,
unsigned long len, unsigned long pgoff,
unsigned long flags, vm_flags_t vm_flags)
{
- struct vm_area_struct *vma;
- struct mm_struct *mm = current->mm;
unsigned long addr = addr0;
struct vm_unmapped_area_info info = {};
@@ -186,16 +200,9 @@ arch_get_unmapped_area_topdown(struct file *filp, unsigned
long addr0,
goto bottomup;
/* requesting a specific address */
- if (addr) {
- addr &= PAGE_MASK;
- if (!mmap_address_hint_valid(addr, len))
- goto get_unmapped_area;
-
- vma = find_vma(mm, addr);
- if (!vma || addr + len <= vm_start_gap(vma))
- return addr;
- }
-get_unmapped_area:
+ addr = arch_mmap_hint(filp, addr, len, pgoff, flags);
+ if (addr)
+ return addr;
info.flags = VM_UNMAPPED_AREA_TOPDOWN;
info.length = len;
diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h
index edeec19d1708..f12d094649f7 100644
--- a/include/linux/sched/mm.h
+++ b/include/linux/sched/mm.h
@@ -205,6 +205,10 @@ unsigned long generic_mmap_hint(struct file *filp,
unsigned long addr,
unsigned long len, unsigned long pgoff,
unsigned long flags);
+unsigned long arch_mmap_hint(struct file *filp, unsigned long addr,
+ unsigned long len, unsigned long pgoff,
+ unsigned long flags);
+
unsigned long
generic_get_unmapped_area(struct file *filp, unsigned long addr,
unsigned long len, unsigned long pgoff,
--
2.47.0.338.g60cca15819-goog
