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

[Matthew Wilcox <willy@infradead.org>]

On Thu, Mar 08, 2018 at 06:35:23PM +0530, Souptick Joarder wrote:
> Use new return type vm_fault_t for fault handler
> in struct vm_operations_struct.
> 
> vmf_insert_mixed(), vmf_insert_pfn() and vmf_insert_page()
> are newly added inline wrapper functions.
> 
> Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>

Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>

Andrew, the plan for these patches is to introduce the typedef, initially
just as documentation ("This function should return a VM_FAULT_ status").
We'll trickle the patches to individual drivers/filesystems in through
the maintainers, as far as possible.  In a few months, we'll probably
dump a pile of patches to unloved drivers on you for merging.  Then we'll
change the typedef to an unsigned int and break the compilation of any
unconverted driver.

Souptick has done a few dozen drivers already, and I've been doing my best
to keep up with reviewing the patches submitted.  There's some interesting
patterns and commonalities between drivers (not to mention a few outright
bugs) that we've noticed, and this'll be a good time to clean them up.

It'd be great to get this into Linus' tree sooner so we can start
submitting the patches to the driver maintainers.