Re: [PATCH] mm: Change return type to vm_fault_t

[Andrew Morton <akpm@linux-foundation.org>]

On Thu, 8 Mar 2018 18:35:23 +0530 Souptick Joarder <jrdr.linux@gmail.com> wrote:

> Use new return type vm_fault_t for fault handler
> in struct vm_operations_struct.

I can't find vm_fault_t?

> vmf_insert_mixed(), vmf_insert_pfn() and vmf_insert_page()
> are newly added inline wrapper functions.

Why?

> index ad06d42..a4d8853 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -379,17 +379,18 @@ struct vm_operations_struct {
>  	void (*close)(struct vm_area_struct * area);
>  	int (*split)(struct vm_area_struct * area, unsigned long addr);
>  	int (*mremap)(struct vm_area_struct * area);
> -	int (*fault)(struct vm_fault *vmf);
> -	int (*huge_fault)(struct vm_fault *vmf, enum page_entry_size pe_size);
> +	vm_fault_t (*fault)(struct vm_fault *vmf);
> +	vm_fault_t (*huge_fault)(struct vm_fault *vmf,
> +			enum page_entry_size pe_size);

Well if we're going to do this then we should convert all the
.page_mkwrite() instances and a bunch of other stuff to use vm_fault_t.
It's a lot of work.  Perhaps we should just keep using "int".