Re: [RFC PATCH] iov_iter: Add an iterator-of-iterators

From: Matthew Wilcox
Date: Wed Mar 22 2023 - 14:49:45 EST


On Wed, Mar 22, 2023 at 06:15:45PM +0000, David Howells wrote:
> @@ -43,17 +44,17 @@ struct iov_iter {
> bool nofault;
> bool data_source;
> bool user_backed;
> - union {
> - size_t iov_offset;
> - int last_offset;
> - };
> + bool spliceable;

We've now up to five u8s in a row here (iter_type, nofault, data_source,
user_backed). Is it time to turn some/all of them into:

bool nofault:1;
bool data_source:1;
bool user_backed:1;
bool spliceable:1;

You can't take the address of them then, but I don't believe we do that
anywhere.