On 11/27/24 09:46, Anuj Gupta wrote:
On Tue, Nov 26, 2024 at 03:45:09PM +0000, Pavel Begunkov wrote:
On 11/26/24 13:54, Anuj Gupta wrote:
On Tue, Nov 26, 2024 at 01:01:03PM +0000, Pavel Begunkov wrote:
On 11/25/24 07:06, Anuj Gupta wrote:
Hmm, I have doubts it's going to work well because the union
members have different sizes. Adding a new type could grow
struct io_uring_attr, which is already bad for uapi. And it
can't be stacked:
How about something like this [1]. I have removed the io_uring_attr
structure, and with the mask scheme the user would pass attributes in
order of their types. Do you still see some cracks?
Looks good to me
--- a/io_uring/rw.c
+++ b/io_uring/rw.c
...
+static int io_prep_rw_pi(struct io_kiocb *req, struct io_rw *rw, int ddir,
+ u64 attr_ptr, u64 attr_type_mask)
+{
+ struct io_uring_attr_pi pi_attr;
+ struct io_async_rw *io;
+ int ret;
+
+ if (copy_from_user(&pi_attr, u64_to_user_ptr(attr_ptr),
+ sizeof(pi_attr)))
+ return -EFAULT;
+
+ if (pi_attr.rsvd)
+ return -EINVAL;
+
+ io = req->async_data;
+ io->meta.flags = pi_attr.flags;
+ io->meta.app_tag = pi_attr.app_tag;
+ io->meta.seed = READ_ONCE(pi_attr.seed);
Seems an unnecessary READ_ONCE slipped here
+ ret = import_ubuf(ddir, u64_to_user_ptr(pi_attr.addr),
+ pi_attr.len, &io->meta.iter);
+ if (unlikely(ret < 0))
+ return ret;
+ rw->kiocb.ki_flags |= IOCB_HAS_METADATA;
+ io_meta_save_state(io);
+ return ret;
+}
...
--
Pavel Begunkov
