Highlevel question: in a lot of the discussions we've used the
term "untorn writes" instead, which feels better than atomic to
me as atomic is a highly overloaded term. Should we switch the
naming to that?
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index 0283cf366c2a..6cb67882bcfd 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -45,6 +45,7 @@
> #include <linux/slab.h>
> #include <linux/maple_tree.h>
> #include <linux/rw_hint.h>
> +#include <linux/uio.h>
fs.h is included almost everywhere, so if we can avoid pulling in
even more dependencies that would be great.
It seems like it is pulled in just for this helper:
> +static inline
> +bool generic_atomic_write_valid(loff_t pos, struct iov_iter *iter)
> +{
> + size_t len = iov_iter_count(iter);
> +
> + if (!iter_is_ubuf(iter))
> + return false;
> +
> + if (!is_power_of_2(len))
> + return false;
> +
> + if (!IS_ALIGNED(pos, len))
> + return false;
> +
> + return true;
> +}
should that just go to uio.h instead, or move out of line?
Also the return type formatting is wrong, the two normal styles are
either:
static inline bool generic_atomic_write_valid(loff_t pos,
struct iov_iter *iter)
or:
static inline bool
generic_atomic_write_valid(loff_t pos, struct iov_iter *iter)
(and while I'm at nitpicking, passing the pos before the iter
feels weird)
Last but not least: if READ/WRITE is passed to kiocb_set_rw_flags,
it should probably set IOCB_WRITE as well? That might be a worthwile
prep patch on it's own.
