From f94fd25cb0aaf77fd7453f31c5d394a1a68ecf60 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 28 Apr 2022 18:45:06 -0600 Subject: tcp: pass back data left in socket after receive This is currently done for CMSG_INQ, add an ability to do so via struct msghdr as well and have CMSG_INQ use that too. If the caller sets msghdr->msg_get_inq, then we'll pass back the hint in msghdr->msg_inq. Rearrange struct msghdr a bit so we can add this member while shrinking it at the same time. On a 64-bit build, it was 96 bytes before this change and 88 bytes afterwards. Reviewed-by: Eric Dumazet Signed-off-by: Jens Axboe Link: https://lore.kernel.org/r/650c22ca-cffc-0255-9a05-2413a1e20826@kernel.dk Signed-off-by: Jakub Kicinski --- include/linux/socket.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/socket.h b/include/linux/socket.h index 6f85f5d957ef..12085c9a8544 100644 --- a/include/linux/socket.h +++ b/include/linux/socket.h @@ -50,6 +50,9 @@ struct linger { struct msghdr { void *msg_name; /* ptr to socket address structure */ int msg_namelen; /* size of socket address structure */ + + int msg_inq; /* output, data left in socket */ + struct iov_iter msg_iter; /* data */ /* @@ -62,8 +65,9 @@ struct msghdr { void __user *msg_control_user; }; bool msg_control_is_user : 1; - __kernel_size_t msg_controllen; /* ancillary data buffer length */ + bool msg_get_inq : 1;/* return INQ after receive */ unsigned int msg_flags; /* flags on received message */ + __kernel_size_t msg_controllen; /* ancillary data buffer length */ struct kiocb *msg_iocb; /* ptr to iocb for async requests */ }; -- cgit v1.2.3 From f548a12efd5ab97e6b1fb332e5634ce44b3d9328 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Tue, 26 Apr 2022 17:39:50 -0600 Subject: io_uring: return hint on whether more data is available after receive For now just use a CQE flag for this, with big CQE support we could return the actual number of bytes left. Signed-off-by: Jens Axboe --- include/uapi/linux/io_uring.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index 49d1f3994f8d..92d1799892b2 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -220,9 +220,11 @@ struct io_uring_cqe { * * IORING_CQE_F_BUFFER If set, the upper 16 bits are the buffer ID * IORING_CQE_F_MORE If set, parent SQE will generate more CQE entries + * IORING_CQE_F_SOCK_NONEMPTY If set, more data to read after socket recv */ #define IORING_CQE_F_BUFFER (1U << 0) #define IORING_CQE_F_MORE (1U << 1) +#define IORING_CQE_F_SOCK_NONEMPTY (1U << 2) enum { IORING_CQE_BUFFER_SHIFT = 16, -- cgit v1.2.3