The patch titled
Subject: arch/x86: teach arch_get_unmapped_area_vmflags to handle hugetlb mappings
has been added to the -mm mm-unstable branch. Its filename is
arch-x86-teach-arch_get_unmapped_area_vmflags-to-handle-hugetlb-mappings.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/arch-x86-teach-arch_get_unmapped_area_vmflags-to-handle-hugetlb-mappings.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Oscar Salvador <osalvador@xxxxxxx>
Subject: arch/x86: teach arch_get_unmapped_area_vmflags to handle hugetlb mappings
Date: Mon, 29 Jul 2024 11:10:12 +0200
We want to stop special casing hugetlb mappings and make them go through
generic channels, so teach arch_get_unmapped_area_{topdown_}vmflags to
handle those.
x86 specific hugetlb function does not set either info.start_gap or
info.align_offset so the same here for compability.
Link: https://lkml.kernel.org/r/20240729091018.2152-4-osalvador@xxxxxxx
Signed-off-by: Oscar Salvador <osalvador@xxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Donet Tom <donettom@xxxxxxxxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Muchun Song <muchun.song@xxxxxxxxx>
Cc: Peter Xu <peterx@xxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/x86/kernel/sys_x86_64.c | 24 ++++++++++++++++--------
1 file changed, 16 insertions(+), 8 deletions(-)
--- a/arch/x86/kernel/sys_x86_64.c~arch-x86-teach-arch_get_unmapped_area_vmflags-to-handle-hugetlb-mappings
+++ a/arch/x86/kernel/sys_x86_64.c
@@ -18,6 +18,7 @@
#include <linux/random.h>
#include <linux/uaccess.h>
#include <linux/elf.h>
+#include <linux/hugetlb.h>
#include <asm/elf.h>
#include <asm/ia32.h>
@@ -25,8 +26,10 @@
/*
* Align a virtual address to avoid aliasing in the I$ on AMD F15h.
*/
-static unsigned long get_align_mask(void)
+static unsigned long get_align_mask(struct file *filp)
{
+ if (filp && is_file_hugepages(filp))
+ return huge_page_mask_align(filp);
/* handle 32- and 64-bit case with a single conditional */
if (va_align.flags < 0 || !(va_align.flags & (2 - mmap_is_ia32())))
return 0;
@@ -49,7 +52,7 @@ static unsigned long get_align_mask(void
*/
static unsigned long get_align_bits(void)
{
- return va_align.bits & get_align_mask();
+ return va_align.bits & get_align_mask(NULL);
}
static int __init control_va_addr_alignment(char *str)
@@ -148,12 +151,15 @@ arch_get_unmapped_area_vmflags(struct fi
info.length = len;
info.low_limit = begin;
info.high_limit = end;
- info.align_offset = pgoff << PAGE_SHIFT;
- info.start_gap = stack_guard_placement(vm_flags);
+ if (!(filp && is_file_hugepages(filp))) {
+ info.align_offset = pgoff << PAGE_SHIFT;
+ info.start_gap = stack_guard_placement(vm_flags);
+ }
if (filp) {
- info.align_mask = get_align_mask();
+ info.align_mask = get_align_mask(filp);
info.align_offset += get_align_bits();
}
+
return vm_unmapped_area(&info);
}
@@ -199,7 +205,10 @@ get_unmapped_area:
info.low_limit = PAGE_SIZE;
info.high_limit = get_mmap_base(0);
- info.start_gap = stack_guard_placement(vm_flags);
+ if (!(filp && is_file_hugepages(filp))) {
+ info.start_gap = stack_guard_placement(vm_flags);
+ info.align_offset = pgoff << PAGE_SHIFT;
+ }
/*
* If hint address is above DEFAULT_MAP_WINDOW, look for unmapped area
@@ -211,9 +220,8 @@ get_unmapped_area:
if (addr > DEFAULT_MAP_WINDOW && !in_32bit_syscall())
info.high_limit += TASK_SIZE_MAX - DEFAULT_MAP_WINDOW;
- info.align_offset = pgoff << PAGE_SHIFT;
if (filp) {
- info.align_mask = get_align_mask();
+ info.align_mask = get_align_mask(filp);
info.align_offset += get_align_bits();
}
addr = vm_unmapped_area(&info);
_
Patches currently in -mm which might be from osalvador@xxxxxxx are
mm-mmap-teach-generic_get_unmapped_area_topdown-to-handle-hugetlb-mappings.patch
arch-s390-teach-arch_get_unmapped_area_topdown-to-handle-hugetlb-mappings.patch
arch-x86-teach-arch_get_unmapped_area_vmflags-to-handle-hugetlb-mappings.patch
arch-sparc-teach-arch_get_unmapped_area_topdown-to-handle-hugetlb-mappings.patch
arch-powerpc-teach-book3s64-arch_get_unmapped_area_topdown-to-handle-hugetlb-mappings.patch
mm-make-hugetlb-mappings-go-through-mm_get_unmapped_area_vmflags.patch
mm-drop-hugetlb_get_unmapped_area_-functions.patch
arch-s390-clean-up-hugetlb-definitions.patch
mm-consolidate-common-checks-in-hugetlb_mmap_check_and_align.patch
