Re: [RFC] situation with csum_and_copy_... API
From: Al Viro
Date: Fri Nov 21 2014 - 14:39:25 EST
On Fri, Nov 21, 2014 at 05:42:55PM +0000, David Laight wrote:
> Callers of kernel_send/recvmsg() could easily be using a wrapper
> function that creates the 'msghdr'.
> When the want to send the remaining part of a buffer the old iterator
> will no longer be available - just the original iov and the required offset.
Er... So why not copy a struct iov_iter to/from msg->msg_iter, then?
It's not as it had been particulary large - 5 words isn't much...
I'm not at all sure that _anything_ has valid reasons for draining iovecs.
Maintaining a struct iov_iter and modifying it is easy and actually faster...
Right now the main examples outside of net/* are due to unfortunate
limitations of ->sendmsg() - until now it had no way to be told that
desired data starts at offset. With ->msg_iter it obviously becomes
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/