On 4/11/23 13:22, Breno Leitao wrote:
On Fri, Apr 07, 2023 at 12:51:44PM -0600, Keith Busch wrote:
@@ -63,14 +63,15 @@ EXPORT_SYMBOL_GPL(io_uring_cmd_done);
int io_uring_cmd_prep_async(struct io_kiocb *req)
{
struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
- size_t cmd_size;
+ size_t size = sizeof(struct io_uring_sqe);
BUILD_BUG_ON(uring_cmd_pdu_size(0) != 16);
BUILD_BUG_ON(uring_cmd_pdu_size(1) != 80);
One minor suggestion. The above is the only user of uring_cmd_pdu_size() now,
which is kind of a convoluted way to enfoce the offset of the 'cmd' field. It
may be more clear to replace these with:
I agree with you here. Basically it is a bug if the payload (pdu) size is
is different than 16 for single SQE or != 80 for extended SQE.
So, basically it is checking for two things:
* the cmd offset is 48
* the io_uring_sqe struct is 64
Since this is a uapi, I am not confidence that they will change at all.
I can replace the code with your suggestion.
BUILD_BUG_ON(offsetof(struct io_uring_sqe, cmd) == 48);
It should be "offset(struct io_uring_sqe, cmd) != 48)", right?
Which is already checked, see io_uring_init()
--
Pavel Begunkov
