android_kernel_xiaomi_sm8350/arch/mips/include/asm/hugetlb.h
Bibo Mao b52b0d996a hugetlb: clear huge pte during flush function on mips platform
[ Upstream commit 33ae8f801ad8bec48e886d368739feb2816478f2 ]

If multiple threads are accessing the same huge page at the same
time, hugetlb_cow will be called if one thread write the COW huge
page. And function huge_ptep_clear_flush is called to notify other
threads to clear the huge pte tlb entry. The other threads clear
the huge pte tlb entry and reload it from page table, the reload
huge pte entry may be old.

This patch fixes this issue on mips platform, and it clears huge
pte entry before notifying other threads to flush current huge
page entry, it is similar with other architectures.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-19 08:53:08 +02:00

98 lines
2.3 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2008, 2009 Cavium Networks, Inc.
*/
#ifndef __ASM_HUGETLB_H
#define __ASM_HUGETLB_H
#include <asm/page.h>
static inline int is_hugepage_only_range(struct mm_struct *mm,
unsigned long addr,
unsigned long len)
{
return 0;
}
#define __HAVE_ARCH_PREPARE_HUGEPAGE_RANGE
static inline int prepare_hugepage_range(struct file *file,
unsigned long addr,
unsigned long len)
{
unsigned long task_size = STACK_TOP;
struct hstate *h = hstate_file(file);
if (len & ~huge_page_mask(h))
return -EINVAL;
if (addr & ~huge_page_mask(h))
return -EINVAL;
if (len > task_size)
return -ENOMEM;
if (task_size - len < addr)
return -EINVAL;
return 0;
}
#define __HAVE_ARCH_HUGE_PTEP_GET_AND_CLEAR
static inline pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
pte_t clear;
pte_t pte = *ptep;
pte_val(clear) = (unsigned long)invalid_pte_table;
set_pte_at(mm, addr, ptep, clear);
return pte;
}
#define __HAVE_ARCH_HUGE_PTEP_CLEAR_FLUSH
static inline void huge_ptep_clear_flush(struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep)
{
/*
* clear the huge pte entry firstly, so that the other smp threads will
* not get old pte entry after finishing flush_tlb_page and before
* setting new huge pte entry
*/
huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);
flush_tlb_page(vma, addr);
}
#define __HAVE_ARCH_HUGE_PTE_NONE
static inline int huge_pte_none(pte_t pte)
{
unsigned long val = pte_val(pte) & ~_PAGE_GLOBAL;
return !val || (val == (unsigned long)invalid_pte_table);
}
#define __HAVE_ARCH_HUGE_PTEP_SET_ACCESS_FLAGS
static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
unsigned long addr,
pte_t *ptep, pte_t pte,
int dirty)
{
int changed = !pte_same(*ptep, pte);
if (changed) {
set_pte_at(vma->vm_mm, addr, ptep, pte);
/*
* There could be some standard sized pages in there,
* get them all.
*/
flush_tlb_range(vma, addr, addr + HPAGE_SIZE);
}
return changed;
}
static inline void arch_clear_hugepage_flags(struct page *page)
{
}
#include <asm-generic/hugetlb.h>
#endif /* __ASM_HUGETLB_H */