Re: [PATCH 3/3] mm: update architecture and driver code to use vm_flags_t

[Anshuman Khandual <anshuman.khandual@arm.com>]

On 19/06/25 1:12 AM, Lorenzo Stoakes wrote:
> In future we intend to change the vm_flags_t type, so it isn't correct for
> architecture and driver code to assume it is unsigned long. Correct this
> assumption across the board.
> 
> Overall, this patch does not introduce any functional change.
> 
> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
> ---
>  arch/arm/mm/fault.c                |  2 +-
>  arch/arm64/include/asm/mman.h      | 10 +++++-----
>  arch/arm64/mm/fault.c              |  2 +-
>  arch/arm64/mm/mmu.c                |  2 +-
>  arch/powerpc/include/asm/mman.h    |  2 +-
>  arch/powerpc/include/asm/pkeys.h   |  4 ++--
>  arch/powerpc/kvm/book3s_hv_uvmem.c |  2 +-
>  arch/sparc/include/asm/mman.h      |  4 ++--
>  arch/x86/kernel/cpu/sgx/encl.c     |  8 ++++----
>  arch/x86/kernel/cpu/sgx/encl.h     |  2 +-
>  tools/testing/vma/vma_internal.h   |  2 +-
>  11 files changed, 20 insertions(+), 20 deletions(-)
> 
> diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
> index ab01b51de559..46169fe42c61 100644
> --- a/arch/arm/mm/fault.c
> +++ b/arch/arm/mm/fault.c
> @@ -268,7 +268,7 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
>  	int sig, code;
>  	vm_fault_t fault;
>  	unsigned int flags = FAULT_FLAG_DEFAULT;
> -	unsigned long vm_flags = VM_ACCESS_FLAGS;
> +	vm_flags_t vm_flags = VM_ACCESS_FLAGS;
>  
>  	if (kprobe_page_fault(regs, fsr))
>  		return 0;
> diff --git a/arch/arm64/include/asm/mman.h b/arch/arm64/include/asm/mman.h
> index 21df8bbd2668..8770c7ee759f 100644
> --- a/arch/arm64/include/asm/mman.h
> +++ b/arch/arm64/include/asm/mman.h
> @@ -11,10 +11,10 @@
>  #include <linux/shmem_fs.h>
>  #include <linux/types.h>
>  
> -static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot,
> +static inline vm_flags_t arch_calc_vm_prot_bits(unsigned long prot,
>  	unsigned long pkey)
>  {
> -	unsigned long ret = 0;
> +	vm_flags_t ret = 0;
>  
>  	if (system_supports_bti() && (prot & PROT_BTI))
>  		ret |= VM_ARM64_BTI;
> @@ -34,8 +34,8 @@ static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot,
>  }
>  #define arch_calc_vm_prot_bits(prot, pkey) arch_calc_vm_prot_bits(prot, pkey)
>  
> -static inline unsigned long arch_calc_vm_flag_bits(struct file *file,
> -						   unsigned long flags)
> +static inline vm_flags_t arch_calc_vm_flag_bits(struct file *file,
> +						unsigned long flags)
>  {
>  	/*
>  	 * Only allow MTE on anonymous mappings as these are guaranteed to be
> @@ -68,7 +68,7 @@ static inline bool arch_validate_prot(unsigned long prot,
>  }
>  #define arch_validate_prot(prot, addr) arch_validate_prot(prot, addr)
>  
> -static inline bool arch_validate_flags(unsigned long vm_flags)
> +static inline bool arch_validate_flags(vm_flags_t vm_flags)
>  {
>  	if (system_supports_mte()) {
>  		/*
> diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
> index ec0a337891dd..24be3e632f79 100644
> --- a/arch/arm64/mm/fault.c
> +++ b/arch/arm64/mm/fault.c
> @@ -549,7 +549,7 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr,
>  	const struct fault_info *inf;
>  	struct mm_struct *mm = current->mm;
>  	vm_fault_t fault;
> -	unsigned long vm_flags;
> +	vm_flags_t vm_flags;
>  	unsigned int mm_flags = FAULT_FLAG_DEFAULT;
>  	unsigned long addr = untagged_addr(far);
>  	struct vm_area_struct *vma;
> diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
> index 8fcf59ba39db..248d96349fd0 100644
> --- a/arch/arm64/mm/mmu.c
> +++ b/arch/arm64/mm/mmu.c
> @@ -720,7 +720,7 @@ void mark_rodata_ro(void)
>  
>  static void __init declare_vma(struct vm_struct *vma,
>  			       void *va_start, void *va_end,
> -			       unsigned long vm_flags)
> +			       vm_flags_t vm_flags)
>  {
>  	phys_addr_t pa_start = __pa_symbol(va_start);
>  	unsigned long size = va_end - va_start;
> diff --git a/arch/powerpc/include/asm/mman.h b/arch/powerpc/include/asm/mman.h
> index 42a51a993d94..912f78a956a1 100644
> --- a/arch/powerpc/include/asm/mman.h
> +++ b/arch/powerpc/include/asm/mman.h
> @@ -14,7 +14,7 @@
>  #include <asm/cpu_has_feature.h>
>  #include <asm/firmware.h>
>  
> -static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot,
> +static inline vm_flags_t arch_calc_vm_prot_bits(unsigned long prot,
>  		unsigned long pkey)
>  {
>  #ifdef CONFIG_PPC_MEM_KEYS
> diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
> index 59a2c7dbc78f..28e752138996 100644
> --- a/arch/powerpc/include/asm/pkeys.h
> +++ b/arch/powerpc/include/asm/pkeys.h
> @@ -30,9 +30,9 @@ extern u32 reserved_allocation_mask; /* bits set for reserved keys */
>  #endif
>  
>  
> -static inline u64 pkey_to_vmflag_bits(u16 pkey)
> +static inline vm_flags_t pkey_to_vmflag_bits(u16 pkey)
>  {
> -	return (((u64)pkey << VM_PKEY_SHIFT) & ARCH_VM_PKEY_FLAGS);
> +	return (((vm_flags_t)pkey << VM_PKEY_SHIFT) & ARCH_VM_PKEY_FLAGS);
>  }
>  
>  static inline int vma_pkey(struct vm_area_struct *vma)
> diff --git a/arch/powerpc/kvm/book3s_hv_uvmem.c b/arch/powerpc/kvm/book3s_hv_uvmem.c
> index 3a6592a31a10..03f8c34fa0a2 100644
> --- a/arch/powerpc/kvm/book3s_hv_uvmem.c
> +++ b/arch/powerpc/kvm/book3s_hv_uvmem.c
> @@ -393,7 +393,7 @@ static int kvmppc_memslot_page_merge(struct kvm *kvm,
>  {
>  	unsigned long gfn = memslot->base_gfn;
>  	unsigned long end, start = gfn_to_hva(kvm, gfn);
> -	unsigned long vm_flags;
> +	vm_flags_t vm_flags;
>  	int ret = 0;
>  	struct vm_area_struct *vma;
>  	int merge_flag = (merge) ? MADV_MERGEABLE : MADV_UNMERGEABLE;
> diff --git a/arch/sparc/include/asm/mman.h b/arch/sparc/include/asm/mman.h
> index af9c10c83dc5..3e4bac33be81 100644
> --- a/arch/sparc/include/asm/mman.h
> +++ b/arch/sparc/include/asm/mman.h
> @@ -28,7 +28,7 @@ static inline void ipi_set_tstate_mcde(void *arg)
>  }
>  
>  #define arch_calc_vm_prot_bits(prot, pkey) sparc_calc_vm_prot_bits(prot)
> -static inline unsigned long sparc_calc_vm_prot_bits(unsigned long prot)
> +static inline vm_flags_t sparc_calc_vm_prot_bits(unsigned long prot)
>  {
>  	if (adi_capable() && (prot & PROT_ADI)) {
>  		struct pt_regs *regs;
> @@ -58,7 +58,7 @@ static inline int sparc_validate_prot(unsigned long prot, unsigned long addr)
>  /* arch_validate_flags() - Ensure combination of flags is valid for a
>   *	VMA.
>   */
> -static inline bool arch_validate_flags(unsigned long vm_flags)
> +static inline bool arch_validate_flags(vm_flags_t vm_flags)
>  {
>  	/* If ADI is being enabled on this VMA, check for ADI
>  	 * capability on the platform and ensure VMA is suitable
> diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c
> index 279148e72459..308dbbae6c6e 100644
> --- a/arch/x86/kernel/cpu/sgx/encl.c
> +++ b/arch/x86/kernel/cpu/sgx/encl.c
> @@ -279,7 +279,7 @@ static struct sgx_encl_page *__sgx_encl_load_page(struct sgx_encl *encl,
>  
>  static struct sgx_encl_page *sgx_encl_load_page_in_vma(struct sgx_encl *encl,
>  						       unsigned long addr,
> -						       unsigned long vm_flags)
> +						       vm_flags_t vm_flags)
>  {
>  	unsigned long vm_prot_bits = vm_flags & VM_ACCESS_FLAGS;
>  	struct sgx_encl_page *entry;
> @@ -520,9 +520,9 @@ static void sgx_vma_open(struct vm_area_struct *vma)
>   * Return: 0 on success, -EACCES otherwise
>   */
>  int sgx_encl_may_map(struct sgx_encl *encl, unsigned long start,
> -		     unsigned long end, unsigned long vm_flags)
> +		     unsigned long end, vm_flags_t vm_flags)
>  {
> -	unsigned long vm_prot_bits = vm_flags & VM_ACCESS_FLAGS;
> +	vm_flags_t vm_prot_bits = vm_flags & VM_ACCESS_FLAGS;
>  	struct sgx_encl_page *page;
>  	unsigned long count = 0;
>  	int ret = 0;
> @@ -605,7 +605,7 @@ static int sgx_encl_debug_write(struct sgx_encl *encl, struct sgx_encl_page *pag
>   */
>  static struct sgx_encl_page *sgx_encl_reserve_page(struct sgx_encl *encl,
>  						   unsigned long addr,
> -						   unsigned long vm_flags)
> +						   vm_flags_t vm_flags)
>  {
>  	struct sgx_encl_page *entry;
>  
> diff --git a/arch/x86/kernel/cpu/sgx/encl.h b/arch/x86/kernel/cpu/sgx/encl.h
> index f94ff14c9486..8ff47f6652b9 100644
> --- a/arch/x86/kernel/cpu/sgx/encl.h
> +++ b/arch/x86/kernel/cpu/sgx/encl.h
> @@ -101,7 +101,7 @@ static inline int sgx_encl_find(struct mm_struct *mm, unsigned long addr,
>  }
>  
>  int sgx_encl_may_map(struct sgx_encl *encl, unsigned long start,
> -		     unsigned long end, unsigned long vm_flags);
> +		     unsigned long end, vm_flags_t vm_flags);
>  
>  bool current_is_ksgxd(void);
>  void sgx_encl_release(struct kref *ref);
> diff --git a/tools/testing/vma/vma_internal.h b/tools/testing/vma/vma_internal.h
> index 7919d7141537..b9eb8c889f96 100644
> --- a/tools/testing/vma/vma_internal.h
> +++ b/tools/testing/vma/vma_internal.h
> @@ -1220,7 +1220,7 @@ static inline void vma_set_page_prot(struct vm_area_struct *vma)
>  	WRITE_ONCE(vma->vm_page_prot, vm_page_prot);
>  }
>  
> -static inline bool arch_validate_flags(unsigned long)
> +static inline bool arch_validate_flags(vm_flags_t)
>  {
>  	return true;
>  }

Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>