Re: [PATCH net-next] sctp: Prepare sctp_v4_get_dst() to dscp_t conversion.
From: Xin Long <lucien.xin@gmail.com>
Date: 2025-01-03 15:36:07
Also in:
linux-sctp
On Thu, Jan 2, 2025 at 11:34 AM Guillaume Nault [off-list ref] wrote:
Define inet_sk_dscp() to get a dscp_t value from struct inet_sock, so that sctp_v4_get_dst() can easily set ->flowi4_tos from a dscp_t variable. For the SCTP_DSCP_SET_MASK case, we can just use inet_dsfield_to_dscp() to get a dscp_t value. Then, when converting ->flowi4_tos from __u8 to dscp_t, we'll just have to drop the inet_dscp_to_dsfield() conversion function.
With inet_dsfield_to_dscp() && inet_dsfield_to_dscp(), the logic looks like: tos(dsfield) -> dscp_t -> tos(dsfield) It's a bit confusing, but it has been doing that all over routing places. In sctp_v4_xmit(), there's the similar tos/dscp thing, although it's not for fl4.flowi4_tos. Also, I'm curious there are still a few places under net/ using: fl4.flowi4_tos = tos & INET_DSCP_MASK; Will you consider changing all of them with inet_dsfield_to_dscp() && inet_dsfield_to_dscp() as well? Thanks.
quoted hunk ↗ jump to hunk
Signed-off-by: Guillaume Nault <redacted> --- include/net/inet_sock.h | 6 ++++++ net/sctp/protocol.c | 10 +++++++--- 2 files changed, 13 insertions(+), 3 deletions(-)diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h index 3ccbad881d74..1086256549fa 100644 --- a/include/net/inet_sock.h +++ b/include/net/inet_sock.h@@ -19,6 +19,7 @@ #include <linux/netdevice.h> #include <net/flow.h> +#include <net/inet_dscp.h> #include <net/sock.h> #include <net/request_sock.h> #include <net/netns/hash.h>@@ -302,6 +303,11 @@ static inline unsigned long inet_cmsg_flags(const struct inet_sock *inet) return READ_ONCE(inet->inet_flags) & IP_CMSG_ALL; } +static inline dscp_t inet_sk_dscp(const struct inet_sock *inet) +{ + return inet_dsfield_to_dscp(READ_ONCE(inet->tos)); +} + #define inet_test_bit(nr, sk) \ test_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags) #define inet_set_bit(nr, sk) \diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c index 8b9a1b96695e..29727ed1008e 100644 --- a/net/sctp/protocol.c +++ b/net/sctp/protocol.c@@ -43,6 +43,7 @@ #include <net/addrconf.h> #include <net/inet_common.h> #include <net/inet_ecn.h> +#include <net/inet_sock.h> #include <net/udp_tunnel.h> #include <net/inet_dscp.h>@@ -427,16 +428,19 @@ static void sctp_v4_get_dst(struct sctp_transport *t, union sctp_addr *saddr, struct dst_entry *dst = NULL; union sctp_addr *daddr = &t->ipaddr; union sctp_addr dst_saddr; - u8 tos = READ_ONCE(inet_sk(sk)->tos); + dscp_t dscp; if (t->dscp & SCTP_DSCP_SET_MASK) - tos = t->dscp & SCTP_DSCP_VAL_MASK; + dscp = inet_dsfield_to_dscp(t->dscp); + else + dscp = inet_sk_dscp(inet_sk(sk)); + memset(&_fl, 0x0, sizeof(_fl)); fl4->daddr = daddr->v4.sin_addr.s_addr; fl4->fl4_dport = daddr->v4.sin_port; fl4->flowi4_proto = IPPROTO_SCTP; if (asoc) { - fl4->flowi4_tos = tos & INET_DSCP_MASK; + fl4->flowi4_tos = inet_dscp_to_dsfield(dscp); fl4->flowi4_scope = ip_sock_rt_scope(asoc->base.sk); fl4->flowi4_oif = asoc->base.sk->sk_bound_dev_if; fl4->fl4_sport = htons(asoc->base.bind_addr.port); --2.39.2