Commit c83efb0d authored by Ma Wupeng's avatar Ma Wupeng Committed by Wupeng Ma
Browse files

arm64: mm: pagemap: Export pbha bit0 info 

hulk inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I96IZH



--------------------------------

Bit 57 is used Commit fb8e37f3 ("mm/pagemap: export uffd-wp protection
information"). Use bit 59 to improve future compatibility for pbha.

Signed-off-by: default avatarMa Wupeng <mawupeng1@huawei.com>
parent bea38841

Documentation/admin-guide/mm/pagemap.rst

+3 −1
Original line number Diff line number Diff line
@@ -21,7 +21,9 @@ There are four components to pagemap: 
    * Bit  55    pte is soft-dirty (see

      :ref:`Documentation/admin-guide/mm/soft-dirty.rst <soft_dirty>`)

    * Bit  56    page exclusively mapped (since 4.2)

    * Bits 57-60 zero

    * Bits 57-58 zero

    * Bit  59    PBHA bit0, used only CONFIG_ARM64_PBHA is enabled

    * Bits 60 zero

    * Bit  61    page is file-page or shared-anon (since 3.5)

    * Bit  62    page swapped

    * Bit  63    page present

fs/proc/task_mmu.c

+15 −0
Original line number Diff line number Diff line
@@ -20,6 +20,7 @@ 
#include <linux/uaccess.h>

#include <linux/pkeys.h>

#include <linux/module.h>

#include <linux/pbha.h>



#include <asm/elf.h>

#include <asm/tlb.h>
@@ -1327,6 +1328,11 @@ struct pagemapread { 
#define PM_PFRAME_MASK		GENMASK_ULL(PM_PFRAME_BITS - 1, 0)

#define PM_SOFT_DIRTY		BIT_ULL(55)

#define PM_MMAP_EXCLUSIVE	BIT_ULL(56)

#ifdef CONFIG_ARM64_PBHA

#define PM_PBHA_BIT0		BIT_ULL(59)

#else

#define PM_PBHA_BIT0		0

#endif

#define PM_FILE			BIT_ULL(61)

#define PM_SWAP			BIT_ULL(62)

#define PM_PRESENT		BIT_ULL(63)
@@ -1419,6 +1425,9 @@ static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, 
			page = device_private_entry_to_page(entry);

	}



	if (pte_pbha(pte))

		flags |= PM_PBHA_BIT0;



	if (page && !PageAnon(page))

		flags |= PM_FILE;

	if (page && !migration && page_mapcount(page) == 1)
@@ -1479,6 +1488,9 @@ static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end, 
		}

#endif



		if (pmd_pbha(pmd))

			flags |= PM_PBHA_BIT0;



		if (page && !migration && page_mapcount(page) == 1)

			flags |= PM_MMAP_EXCLUSIVE;
@@ -1711,6 +1723,9 @@ static int get_pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long 
		pmd_t pmd = *pmdp;

		struct page *page = NULL;



		if (pmd_pbha(pmd))

			flags |= PM_PBHA_BIT0;



		if (pmd_present(pmd)) {

			page = pmd_page(pmd);

			flags |= PM_PRESENT;

include/linux/pbha.h

+24 −0
Original line number Diff line number Diff line
@@ -54,6 +54,22 @@ static inline pte_t maybe_mk_pbha_bit0(pte_t pte, struct vm_area_struct *vma) 


	return pte;

}



static inline bool pte_pbha(pte_t pte)

{

	if (!system_support_pbha_bit0())

		return false;



	return !!(pte_val(pte) & (PBHA_VAL_BIT0 << PBHA_BITS_SHIFT));

}



static inline bool pmd_pbha(pmd_t pmd)

{

	if (!system_support_pbha_bit0())

		return false;



	return !!(pmd_val(pmd) & (PBHA_VAL_BIT0 << PBHA_BITS_SHIFT));

}

#else

static inline bool system_support_pbha_bit0(void) { return false; }

static inline pgprot_t pgprot_pbha_bit0(pgprot_t prot) { return prot; }
@@ -61,6 +77,14 @@ static inline pte_t maybe_mk_pbha_bit0(pte_t pte, struct vm_area_struct *vma) 
{

	return pte;

}

static inline bool pte_pbha(pte_t pte)

{

	return false;

}

static inline bool pmd_pbha(pmd_t pte)

{

	return false;

}

#endif



#endif