On Wed, Dec 11, 2019 at 7:29 AM Jens Axboe <axboe@xxxxxxxxx> wrote:
>
> This is in preparation for passing in a flag to the iomap_actor, which
> currently doesn't support that.
This really looks like we should use a struct for passing the arguments, no?
Now on 64-bit, you the iomap_actor() has seven arguments, which
already means that it's passing some of them on the stack on most
architectures.
On 32-bit, it's even worse, because two of the arguments are "loff_t",
which means that they are 2 words each, so you have 9 words of
arguments. I don't know a single architecture that does register
passing for things like that.
If you were to change the calling convention _first_ to do a "struct
iomap_actor" or whatever, then adding the "flags" field would be a
trivial addition.
Linus
