mm: make mm->flags a bitmap and 64-bit on all arches

[PATCH 04/10] mm: convert arch-specific code to mm_flags_*() accessors

Posted by Lorenzo Stoakes 1 month, 3 weeks ago

As part of the effort to move to mm->flags becoming a bitmap field, convert
existing users to making use of the mm_flags_*() accessors which will, when
the conversion is complete, be the only means of accessing mm_struct flags.

No functional change intended.

Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
---
 arch/s390/mm/mmap.c              | 4 ++--
 arch/sparc/kernel/sys_sparc_64.c | 4 ++--
 arch/x86/mm/mmap.c               | 4 ++--
 3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c
index 40a526d28184..c884b580eb5e 100644
--- a/arch/s390/mm/mmap.c
+++ b/arch/s390/mm/mmap.c
@@ -182,10 +182,10 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
 	 */
 	if (mmap_is_legacy(rlim_stack)) {
 		mm->mmap_base = mmap_base_legacy(random_factor);
-		clear_bit(MMF_TOPDOWN, &mm->flags);
+		mm_flags_clear(MMF_TOPDOWN, mm);
 	} else {
 		mm->mmap_base = mmap_base(random_factor, rlim_stack);
-		set_bit(MMF_TOPDOWN, &mm->flags);
+		mm_flag_set(MMF_TOPDOWN, mm);
 	}
 }
 
diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c
index c5a284df7b41..785e9909340f 100644
--- a/arch/sparc/kernel/sys_sparc_64.c
+++ b/arch/sparc/kernel/sys_sparc_64.c
@@ -309,7 +309,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
 	    gap == RLIM_INFINITY ||
 	    sysctl_legacy_va_layout) {
 		mm->mmap_base = TASK_UNMAPPED_BASE + random_factor;
-		clear_bit(MMF_TOPDOWN, &mm->flags);
+		mm_flags_clear(MMF_TOPDOWN, mm);
 	} else {
 		/* We know it's 32-bit */
 		unsigned long task_size = STACK_TOP32;
@@ -320,7 +320,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
 			gap = (task_size / 6 * 5);
 
 		mm->mmap_base = PAGE_ALIGN(task_size - gap - random_factor);
-		set_bit(MMF_TOPDOWN, &mm->flags);
+		mm_flags_set(MMF_TOPDOWN, mm);
 	}
 }
 
diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c
index 5ed2109211da..708f85dc9380 100644
--- a/arch/x86/mm/mmap.c
+++ b/arch/x86/mm/mmap.c
@@ -122,9 +122,9 @@ static void arch_pick_mmap_base(unsigned long *base, unsigned long *legacy_base,
 void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
 {
 	if (mmap_is_legacy())
-		clear_bit(MMF_TOPDOWN, &mm->flags);
+		mm_flags_clear(MMF_TOPDOWN, mm);
 	else
-		set_bit(MMF_TOPDOWN, &mm->flags);
+		mm_flags_set(MMF_TOPDOWN, mm);
 
 	arch_pick_mmap_base(&mm->mmap_base, &mm->mmap_legacy_base,
 			arch_rnd(mmap64_rnd_bits), task_size_64bit(0),
-- 
2.50.1

Re: [PATCH 04/10] mm: convert arch-specific code to mm_flags_*() accessors

Posted by David Hildenbrand 1 month, 1 week ago

On 12.08.25 17:44, Lorenzo Stoakes wrote:
> As part of the effort to move to mm->flags becoming a bitmap field, convert
> existing users to making use of the mm_flags_*() accessors which will, when
> the conversion is complete, be the only means of accessing mm_struct flags.
> 
> No functional change intended.
> 
> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
> ---

Acked-by: David Hildenbrand <david@redhat.com>

-- 
Cheers

David / dhildenb

Re: [PATCH 04/10] mm: convert arch-specific code to mm_flags_*() accessors

Posted by Mike Rapoport 1 month, 3 weeks ago

On Tue, Aug 12, 2025 at 04:44:13PM +0100, Lorenzo Stoakes wrote:
> As part of the effort to move to mm->flags becoming a bitmap field, convert
> existing users to making use of the mm_flags_*() accessors which will, when
> the conversion is complete, be the only means of accessing mm_struct flags.
> 
> No functional change intended.
> 
> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>

Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>

> ---
>  arch/s390/mm/mmap.c              | 4 ++--
>  arch/sparc/kernel/sys_sparc_64.c | 4 ++--
>  arch/x86/mm/mmap.c               | 4 ++--
>  3 files changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c
> index 40a526d28184..c884b580eb5e 100644
> --- a/arch/s390/mm/mmap.c
> +++ b/arch/s390/mm/mmap.c
> @@ -182,10 +182,10 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
>  	 */
>  	if (mmap_is_legacy(rlim_stack)) {
>  		mm->mmap_base = mmap_base_legacy(random_factor);
> -		clear_bit(MMF_TOPDOWN, &mm->flags);
> +		mm_flags_clear(MMF_TOPDOWN, mm);
>  	} else {
>  		mm->mmap_base = mmap_base(random_factor, rlim_stack);
> -		set_bit(MMF_TOPDOWN, &mm->flags);
> +		mm_flag_set(MMF_TOPDOWN, mm);
>  	}
>  }
>  
> diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c
> index c5a284df7b41..785e9909340f 100644
> --- a/arch/sparc/kernel/sys_sparc_64.c
> +++ b/arch/sparc/kernel/sys_sparc_64.c
> @@ -309,7 +309,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
>  	    gap == RLIM_INFINITY ||
>  	    sysctl_legacy_va_layout) {
>  		mm->mmap_base = TASK_UNMAPPED_BASE + random_factor;
> -		clear_bit(MMF_TOPDOWN, &mm->flags);
> +		mm_flags_clear(MMF_TOPDOWN, mm);
>  	} else {
>  		/* We know it's 32-bit */
>  		unsigned long task_size = STACK_TOP32;
> @@ -320,7 +320,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
>  			gap = (task_size / 6 * 5);
>  
>  		mm->mmap_base = PAGE_ALIGN(task_size - gap - random_factor);
> -		set_bit(MMF_TOPDOWN, &mm->flags);
> +		mm_flags_set(MMF_TOPDOWN, mm);
>  	}
>  }
>  
> diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c
> index 5ed2109211da..708f85dc9380 100644
> --- a/arch/x86/mm/mmap.c
> +++ b/arch/x86/mm/mmap.c
> @@ -122,9 +122,9 @@ static void arch_pick_mmap_base(unsigned long *base, unsigned long *legacy_base,
>  void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
>  {
>  	if (mmap_is_legacy())
> -		clear_bit(MMF_TOPDOWN, &mm->flags);
> +		mm_flags_clear(MMF_TOPDOWN, mm);
>  	else
> -		set_bit(MMF_TOPDOWN, &mm->flags);
> +		mm_flags_set(MMF_TOPDOWN, mm);
>  
>  	arch_pick_mmap_base(&mm->mmap_base, &mm->mmap_legacy_base,
>  			arch_rnd(mmap64_rnd_bits), task_size_64bit(0),
> -- 
> 2.50.1
> 

-- 
Sincerely yours,
Mike.

Re: [PATCH 04/10] mm: convert arch-specific code to mm_flags_*() accessors

Posted by Lorenzo Stoakes 1 month, 3 weeks ago

Hi Andrew,

One very small fix for this, I typo'd the function name... :)

Cheers, Lorenzo

----8<----
From c2f9bc16a4ad705ac05571ac7b825d8aac5849d4 Mon Sep 17 00:00:00 2001
From: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Date: Wed, 13 Aug 2025 15:08:36 +0100
Subject: [PATCH] fix typo

Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202508132154.feFNDPyq-lkp@intel.com/
---
 arch/s390/mm/mmap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c
index c884b580eb5e..547104ccc22a 100644
--- a/arch/s390/mm/mmap.c
+++ b/arch/s390/mm/mmap.c
@@ -185,7 +185,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
 		mm_flags_clear(MMF_TOPDOWN, mm);
 	} else {
 		mm->mmap_base = mmap_base(random_factor, rlim_stack);
-		mm_flag_set(MMF_TOPDOWN, mm);
+		mm_flags_set(MMF_TOPDOWN, mm);
 	}
 }

--
2.50.1

Re: [PATCH 04/10] mm: convert arch-specific code to mm_flags_*() accessors

Posted by Liam R. Howlett 1 month, 3 weeks ago

* Lorenzo Stoakes <lorenzo.stoakes@oracle.com> [250812 11:47]:
> As part of the effort to move to mm->flags becoming a bitmap field, convert
> existing users to making use of the mm_flags_*() accessors which will, when
> the conversion is complete, be the only means of accessing mm_struct flags.
> 
> No functional change intended.
> 
> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>

Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>

> ---
>  arch/s390/mm/mmap.c              | 4 ++--
>  arch/sparc/kernel/sys_sparc_64.c | 4 ++--
>  arch/x86/mm/mmap.c               | 4 ++--
>  3 files changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c
> index 40a526d28184..c884b580eb5e 100644
> --- a/arch/s390/mm/mmap.c
> +++ b/arch/s390/mm/mmap.c
> @@ -182,10 +182,10 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
>  	 */
>  	if (mmap_is_legacy(rlim_stack)) {
>  		mm->mmap_base = mmap_base_legacy(random_factor);
> -		clear_bit(MMF_TOPDOWN, &mm->flags);
> +		mm_flags_clear(MMF_TOPDOWN, mm);
>  	} else {
>  		mm->mmap_base = mmap_base(random_factor, rlim_stack);
> -		set_bit(MMF_TOPDOWN, &mm->flags);
> +		mm_flag_set(MMF_TOPDOWN, mm);
>  	}
>  }
>  
> diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c
> index c5a284df7b41..785e9909340f 100644
> --- a/arch/sparc/kernel/sys_sparc_64.c
> +++ b/arch/sparc/kernel/sys_sparc_64.c
> @@ -309,7 +309,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
>  	    gap == RLIM_INFINITY ||
>  	    sysctl_legacy_va_layout) {
>  		mm->mmap_base = TASK_UNMAPPED_BASE + random_factor;
> -		clear_bit(MMF_TOPDOWN, &mm->flags);
> +		mm_flags_clear(MMF_TOPDOWN, mm);
>  	} else {
>  		/* We know it's 32-bit */
>  		unsigned long task_size = STACK_TOP32;
> @@ -320,7 +320,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
>  			gap = (task_size / 6 * 5);
>  
>  		mm->mmap_base = PAGE_ALIGN(task_size - gap - random_factor);
> -		set_bit(MMF_TOPDOWN, &mm->flags);
> +		mm_flags_set(MMF_TOPDOWN, mm);
>  	}
>  }
>  
> diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c
> index 5ed2109211da..708f85dc9380 100644
> --- a/arch/x86/mm/mmap.c
> +++ b/arch/x86/mm/mmap.c
> @@ -122,9 +122,9 @@ static void arch_pick_mmap_base(unsigned long *base, unsigned long *legacy_base,
>  void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
>  {
>  	if (mmap_is_legacy())
> -		clear_bit(MMF_TOPDOWN, &mm->flags);
> +		mm_flags_clear(MMF_TOPDOWN, mm);
>  	else
> -		set_bit(MMF_TOPDOWN, &mm->flags);
> +		mm_flags_set(MMF_TOPDOWN, mm);
>  
>  	arch_pick_mmap_base(&mm->mmap_base, &mm->mmap_legacy_base,
>  			arch_rnd(mmap64_rnd_bits), task_size_64bit(0),
> -- 
> 2.50.1
>