[PATCH 2/5] mm: update ptep_modify_prot_commit to take old pte value as arg

From: Aneesh Kumar K.V
Date: Wed Oct 10 2018 - 23:53:35 EST


Architectures like ppc64 requires to do a conditional tlb flush based on the old
and new value of pte. Enable that by passing old pte value as the arg.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
---
arch/s390/include/asm/pgtable.h | 3 ++-
arch/s390/mm/pgtable.c | 2 +-
arch/x86/include/asm/paravirt.h | 2 +-
fs/proc/task_mmu.c | 8 +++++---
include/asm-generic/pgtable.h | 2 +-
mm/memory.c | 8 ++++----
mm/mprotect.c | 6 +++---
7 files changed, 17 insertions(+), 14 deletions(-)

diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 8e7f26dfedc6..626250436897 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -1036,7 +1036,8 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm,

#define __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
pte_t ptep_modify_prot_start(struct vm_area_struct *, unsigned long, pte_t *);
-void ptep_modify_prot_commit(struct vm_area_struct *, unsigned long, pte_t *, pte_t);
+void ptep_modify_prot_commit(struct vm_area_struct *, unsigned long,
+ pte_t *, pte_t, pte_t);

#define __HAVE_ARCH_PTEP_CLEAR_FLUSH
static inline pte_t ptep_clear_flush(struct vm_area_struct *vma,
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index 29c0a21cd34a..b283b92722cc 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -322,7 +322,7 @@ pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr,
EXPORT_SYMBOL(ptep_modify_prot_start);

void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr,
- pte_t *ptep, pte_t pte)
+ pte_t *ptep, pte_t old_pte, pte_t pte)
{
pgste_t pgste;
struct mm_struct *mm = vma->vm_mm;
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index c5d203a51e50..17214e074286 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -434,7 +434,7 @@ static inline pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned
}

static inline void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr,
- pte_t *ptep, pte_t pte)
+ pte_t *ptep, pte_t old_pte, pte_t pte)
{
struct mm_struct *mm = vma->vm_mm;

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 229df16e7ad0..505aa21d04df 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -938,10 +938,12 @@ static inline void clear_soft_dirty(struct vm_area_struct *vma,
pte_t ptent = *pte;

if (pte_present(ptent)) {
- ptent = ptep_modify_prot_start(vma, addr, pte);
- ptent = pte_wrprotect(ptent);
+ pte_t old_pte;
+
+ old_pte = ptep_modify_prot_start(vma, addr, pte);
+ ptent = pte_wrprotect(old_pte);
ptent = pte_clear_soft_dirty(ptent);
- ptep_modify_prot_commit(vma, addr, pte, ptent);
+ ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent);
} else if (is_swap_pte(ptent)) {
ptent = pte_swp_clear_soft_dirty(ptent);
set_pte_at(vma->vm_mm, addr, pte, ptent);
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index 021b94cd3260..4e4723f6be5e 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -619,7 +619,7 @@ static inline pte_t ptep_modify_prot_start(struct vm_area_struct *vma,
*/
static inline void ptep_modify_prot_commit(struct vm_area_struct *vma,
unsigned long addr,
- pte_t *ptep, pte_t pte)
+ pte_t *ptep, pte_t old_pte, pte_t pte)
{
__ptep_modify_prot_commit(vma->vm_mm, addr, ptep, pte);
}
diff --git a/mm/memory.c b/mm/memory.c
index 261d30f51499..211df764f232 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3786,7 +3786,7 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf)
int last_cpupid;
int target_nid;
bool migrated = false;
- pte_t pte;
+ pte_t pte, old_pte;
bool was_writable = pte_savedwrite(vmf->orig_pte);
int flags = 0;

@@ -3806,12 +3806,12 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf)
* Make it present again, Depending on how arch implementes non
* accessible ptes, some can allow access by kernel mode.
*/
- pte = ptep_modify_prot_start(vma, vmf->address, vmf->pte);
- pte = pte_modify(pte, vma->vm_page_prot);
+ old_pte = ptep_modify_prot_start(vma, vmf->address, vmf->pte);
+ pte = pte_modify(old_pte, vma->vm_page_prot);
pte = pte_mkyoung(pte);
if (was_writable)
pte = pte_mkwrite(pte);
- ptep_modify_prot_commit(vma, vmf->address, vmf->pte, pte);
+ ptep_modify_prot_commit(vma, vmf->address, vmf->pte, old_pte, pte);
update_mmu_cache(vma, vmf->address, vmf->pte);

page = vm_normal_page(vma, vmf->address, pte);
diff --git a/mm/mprotect.c b/mm/mprotect.c
index a301d4c83d3c..1b46b1b1248d 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -110,8 +110,8 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
continue;
}

- ptent = ptep_modify_prot_start(vma, addr, pte);
- ptent = pte_modify(ptent, newprot);
+ oldpte = ptep_modify_prot_start(vma, addr, pte);
+ ptent = pte_modify(oldpte, newprot);
if (preserve_write)
ptent = pte_mk_savedwrite(ptent);

@@ -121,7 +121,7 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
!(vma->vm_flags & VM_SOFTDIRTY))) {
ptent = pte_mkwrite(ptent);
}
- ptep_modify_prot_commit(vma, addr, pte, ptent);
+ ptep_modify_prot_commit(vma, addr, pte, oldpte, ptent);
pages++;
} else if (IS_ENABLED(CONFIG_MIGRATION)) {
swp_entry_t entry = pte_to_swp_entry(oldpte);
--
2.17.1