Re: [PATCH 07/21] shmem: document how to "persist" data when using shmem_*file_setup

Christoph Hellwig
2024-01-29T16:04:26Z

On Mon, Jan 29, 2024 at 03:56:58PM +0000, Matthew Wilcox wrote:
> Could I trouble you to elaborate on what you'd like to see a filesystem
> like ubifs do to replace write_begin/write_end? After my recent patches,
> those are the only places in ubifs that have a struct page reference.
> I've been holding off on converting those and writepage because we have
> plans to eliminate them, but I'm not sure how much longer we can hold off.

I think the abstraction is okay for anyone using generic_perform_write.
The problem with them is that they are not generic operations called
by higher level code, but callbacks that depend on caller context.
So in perfect world they would be passed directly to
generic_perform_write and the few other users and not go through aops.