Merge branch 'add-support-for-so_priority-cmsg'

Anna Emese Nyiri says:

====================
Add support for SO_PRIORITY cmsg

Introduce a new helper function, `sk_set_prio_allowed`,
to centralize the logic for validating priority settings.
Add support for the `SO_PRIORITY` control message,
enabling user-space applications to set socket priority
via control messages (cmsg).
====================

Link: https://patch.msgid.link/20241213084457.45120-1-annaemesenyiri@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

4 files changed, 10 insertions, 4 deletions

diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
index 56d8bc5593d3..3ccbad881d74 100644
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -172,7 +172,7 @@ struct inet_cork {
 	u8			tx_flags;
 	__u8			ttl;
 	__s16			tos;
-	char			priority;
+	u32			priority;
 	__u16			gso_size;
 	u32			ts_opt_id;
 	u64			transmit_time;
diff --git a/include/net/ip.h b/include/net/ip.h
index 0e548c1f2a0e..9f5e33e371fc 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -81,7 +81,6 @@ struct ipcm_cookie {
 	__u8			protocol;
 	__u8			ttl;
 	__s16			tos;
-	char			priority;
 	__u16			gso_size;
 };
 
@@ -96,6 +95,7 @@ static inline void ipcm_init_sk(struct ipcm_cookie *ipcm,
 	ipcm_init(ipcm);
 
 	ipcm->sockc.mark = READ_ONCE(inet->sk.sk_mark);
+	ipcm->sockc.priority = READ_ONCE(inet->sk.sk_priority);
 	ipcm->sockc.tsflags = READ_ONCE(inet->sk.sk_tsflags);
 	ipcm->oif = READ_ONCE(inet->sk.sk_bound_dev_if);
 	ipcm->addr = inet->inet_saddr;
diff --git a/include/net/sock.h b/include/net/sock.h
index 7464e9f9f47c..d4bdd3286e03 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -953,6 +953,7 @@ enum sock_flags {
 	SOCK_XDP, /* XDP is attached */
 	SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
 	SOCK_RCVMARK, /* Receive SO_MARK  ancillary data with packet */
+	SOCK_RCVPRIORITY, /* Receive SO_PRIORITY ancillary data with packet */
 };
 
 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
@@ -1814,13 +1815,15 @@ struct sockcm_cookie {
 	u32 mark;
 	u32 tsflags;
 	u32 ts_opt_id;
+	u32 priority;
 };
 
 static inline void sockcm_init(struct sockcm_cookie *sockc,
 			       const struct sock *sk)
 {
 	*sockc = (struct sockcm_cookie) {
-		.tsflags = READ_ONCE(sk->sk_tsflags)
+		.tsflags = READ_ONCE(sk->sk_tsflags),
+		.priority = READ_ONCE(sk->sk_priority),
 	};
 }
 
@@ -2658,7 +2661,8 @@ static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
 {
 #define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL)			| \
 			   (1UL << SOCK_RCVTSTAMP)			| \
-			   (1UL << SOCK_RCVMARK))
+			   (1UL << SOCK_RCVMARK)			|\
+			   (1UL << SOCK_RCVPRIORITY))
 #define TSFLAGS_ANY	  (SOF_TIMESTAMPING_SOFTWARE			| \
 			   SOF_TIMESTAMPING_RAW_HARDWARE)
 
diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h
index deacfd6dd197..aa5016ff3d91 100644
--- a/include/uapi/asm-generic/socket.h
+++ b/include/uapi/asm-generic/socket.h
@@ -143,6 +143,8 @@
 
 #define SCM_TS_OPT_ID		81
 
+#define SO_RCVPRIORITY		82
+
 #if !defined(__KERNEL__)
 
 #if __BITS_PER_LONG == 64 || (defined(__x86_64__) && defined(__ILP32__))