Re: [RFC PATCH v1 4/9] uaccess: Introduce copy_{to/from}_user_partial()
Geert Uytterhoeven <[email protected]>
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Hi Christophe, Thanks for your patch! On Mon, 27 Apr 2026 at 19:18, Christophe Leroy (CS GROUP) <[email protected]> wrote: > Today there are approximately 3000 calls for copy_to_user() and > 3000 calls to copy_from_user(). > > The majority of callers of copy_{to/from}_user() don't care about the > return value, they only check whether it is 0 or not, and when it is > not 0 they handle it as a -EACCES. I think the "a" can be dropped. > In order to allow better optimisation of copy_{to/from}_user() when > the size of the copy is known at build time, create new fonctions functions > named copy_{to/from}_user_partial() to be used by the few callers > that are interested in partial copies and need to now how many know > bytes remain at the end of the copy. > > For the time being it is just the same as copy_{to/from}_user(). > > Signed-off-by: Christophe Leroy (CS GROUP) <[email protected]> Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected] In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds