[PATCH 4/5] io_uring/kbuf: rename struct io_uring_buf_reg 'pad' to'flags'

[Jens Axboe <axboe@kernel.dk>]

In preparation for allowing flags to be set for registration, rename
the padding and use it for that.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 include/uapi/linux/io_uring.h | 2 +-
 io_uring/kbuf.c               | 8 ++++++--
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index 709de6d4feb2..c3f3ea997f3a 100644
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -640,7 +640,7 @@ struct io_uring_buf_reg {
 	__u64	ring_addr;
 	__u32	ring_entries;
 	__u16	bgid;
-	__u16	pad;
+	__u16	flags;
 	__u64	resv[3];
 };
 
diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c
index db5f189267b7..4b2f4a0ee962 100644
--- a/io_uring/kbuf.c
+++ b/io_uring/kbuf.c
@@ -494,7 +494,9 @@ int io_register_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg)
 	if (copy_from_user(&reg, arg, sizeof(reg)))
 		return -EFAULT;
 
-	if (reg.pad || reg.resv[0] || reg.resv[1] || reg.resv[2])
+	if (reg.resv[0] || reg.resv[1] || reg.resv[2])
+		return -EINVAL;
+	if (reg.flags)
 		return -EINVAL;
 	if (!reg.ring_addr)
 		return -EFAULT;
@@ -544,7 +546,9 @@ int io_unregister_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg)
 
 	if (copy_from_user(&reg, arg, sizeof(reg)))
 		return -EFAULT;
-	if (reg.pad || reg.resv[0] || reg.resv[1] || reg.resv[2])
+	if (reg.resv[0] || reg.resv[1] || reg.resv[2])
+		return -EINVAL;
+	if (reg.flags)
 		return -EINVAL;
 
 	bl = io_buffer_get_list(ctx, reg.bgid);
-- 
2.39.2