[RFC PATCH RESEND 18/28] mm: add FAULT_FLAG_VMA_LOCK flag

[Laurent Dufour]

Le 01/09/2022 à 19:35, Suren Baghdasaryan a écrit :
> Add a new flag to distinguish page faults handled under protection of
> per-vma lock.
> 
> Signed-off-by: Suren Baghdasaryan <surenb at google.com>

FWIW,

Reviewed-by: Laurent Dufour <laurent.dufour at fr.ibm.com>

> ---
>  include/linux/mm.h       | 3 ++-
>  include/linux/mm_types.h | 1 +
>  2 files changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 0d9c1563c354..7c3190eaabd7 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -466,7 +466,8 @@ static inline bool fault_flag_allow_retry_first(enum fault_flag flags)
>  	{ FAULT_FLAG_USER,		"USER" }, \
>  	{ FAULT_FLAG_REMOTE,		"REMOTE" }, \
>  	{ FAULT_FLAG_INSTRUCTION,	"INSTRUCTION" }, \
> -	{ FAULT_FLAG_INTERRUPTIBLE,	"INTERRUPTIBLE" }
> +	{ FAULT_FLAG_INTERRUPTIBLE,	"INTERRUPTIBLE" }, \
> +	{ FAULT_FLAG_VMA_LOCK,		"VMA_LOCK" }
>  
>  /*
>   * vm_fault is filled by the pagefault handler and passed to the vma's
> diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
> index 6a03f59c1e78..36562e702baf 100644
> --- a/include/linux/mm_types.h
> +++ b/include/linux/mm_types.h
> @@ -886,6 +886,7 @@ enum fault_flag {
>  	FAULT_FLAG_INTERRUPTIBLE =	1 << 9,
>  	FAULT_FLAG_UNSHARE =		1 << 10,
>  	FAULT_FLAG_ORIG_PTE_VALID =	1 << 11,
> +	FAULT_FLAG_VMA_LOCK =		1 << 12,
>  };
>  
>  typedef unsigned int __bitwise zap_flags_t;