From df30285b3670bf52e1e5512e4d4482bec5e93c16 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Wed, 2 Jul 2025 22:35:18 +0000 Subject: af_unix: Introduce SO_INQ. We have an application that uses almost the same code for TCP and AF_UNIX (SOCK_STREAM). TCP can use TCP_INQ, but AF_UNIX doesn't have it and requires an extra syscall, ioctl(SIOCINQ) or getsockopt(SO_MEMINFO) as an alternative. Let's introduce the generic version of TCP_INQ. If SO_INQ is enabled, recvmsg() will put a cmsg of SCM_INQ that contains the exact value of ioctl(SIOCINQ). The cmsg is also included when msg->msg_get_inq is non-zero to make sockets io_uring-friendly. Note that SOCK_CUSTOM_SOCKOPT is flagged only for SOCK_STREAM to override setsockopt() for SOL_SOCKET. By having the flag in struct unix_sock, instead of struct sock, we can later add SO_INQ support for TCP and reuse tcp_sk(sk)->recvmsg_inq. Note also that supporting custom getsockopt() for SOL_SOCKET will need preparation for other SOCK_CUSTOM_SOCKOPT users (UDP, vsock, MPTCP). Signed-off-by: Kuniyuki Iwashima Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20250702223606.1054680-7-kuniyu@google.com Signed-off-by: Jakub Kicinski --- arch/sparc/include/uapi/asm/socket.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'arch/sparc/include/uapi/asm/socket.h') diff --git a/arch/sparc/include/uapi/asm/socket.h b/arch/sparc/include/uapi/asm/socket.h index adcba7329386..71befa109e1c 100644 --- a/arch/sparc/include/uapi/asm/socket.h +++ b/arch/sparc/include/uapi/asm/socket.h @@ -145,6 +145,9 @@ #define SO_PASSRIGHTS 0x005c +#define SO_INQ 0x005d +#define SCM_INQ SO_INQ + #if !defined(__KERNEL__) -- cgit v1.2.3