On Mon, Feb 01, 2021 at 12:04:49PM +0200, Boris Pismenny wrote:
> +static __always_inline __must_check
> +size_t ddp_copy_to_iter(const void *addr, size_t bytes, struct iov_iter *i)
> +{
> + if (unlikely(!check_copy_size(addr, bytes, true)))
> + return 0;
> + else
> + return _ddp_copy_to_iter(addr, bytes, i);
> +}
No need for the else after a return, and the normal kernel convention
double underscores for magic internal functions.
But more importantly: does this belong into the generic header without
and comments what the ddp means and when it should be used?
> +static void ddp_memcpy_to_page(struct page *page, size_t offset, const char
> *from, size_t len)
Overly long line. But we're also looking into generic helpers for
this kind of things, not sure if they made it to linux-next in the
meantime, but please check.
> +size_t _ddp_copy_to_iter(const void *addr, size_t bytes, struct iov_iter *i)
> +{
> + const char *from = addr;
> + if (unlikely(iov_iter_is_pipe(i)))
> + return copy_pipe_to_iter(addr, bytes, i);
> + if (iter_is_iovec(i))
> + might_fault();
> + iterate_and_advance(i, bytes, v,
> + copyout(v.iov_base, (from += v.iov_len) - v.iov_len, v.iov_len),
> + ddp_memcpy_to_page(v.bv_page, v.bv_offset,
> + (from += v.bv_len) - v.bv_len, v.bv_len),
> + memcpy(v.iov_base, (from += v.iov_len) - v.iov_len, v.iov_len)
> + )
> +
> + return bytes;
> +}
This bloats every kernel build, so please move it into a conditionally
built file. And please document the whole thing.
