[RFC 2/5] io_uring/cmd: give inline space in request to cmds

Pavel Begunkov
2024-08-14T10:45:28Z

Some io_uring commands can use some inline space in io_kiocb. We have 32
bytes in struct io_uring_cmd, expose it.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
include/linux/io_uring/cmd.h | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/include/linux/io_uring/cmd.h b/include/linux/io_uring/cmd.h
index 86ceb3383e49..c189d36ad55e 100644
--- a/include/linux/io_uring/cmd.h
+++ b/include/linux/io_uring/cmd.h
@@ -23,6 +23,15 @@ static inline const void *io_uring_sqe_cmd(const struct io_uring_sqe *sqe)
return sqe->cmd;
}

+static inline void io_uring_cmd_private_sz_check(size_t cmd_sz)
+{
+ BUILD_BUG_ON(cmd_sz > sizeof_field(struct io_uring_cmd, pdu));
+}
+#define io_uring_cmd_to_pdu(cmd, pdu_type) ( \
+ io_uring_cmd_private_sz_check(sizeof(pdu_type)), \
+ ((pdu_type *)&(cmd)->pdu) \
+)
+
#if defined(CONFIG_IO_URING)
int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
struct iov_iter *iter, void *ioucmd);
--
2.45.2