git: b471d23a6a66 - main - ktls: add global generation count

[Konstantin Belousov]

The branch main has been updated by kib:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=b471d23a6a667f54c84b3bb7ed04ea75931ef2b8

commit b471d23a6a667f54c84b3bb7ed04ea75931ef2b8
Author:     Konstantin Belousov <k...@freebsd.org>
AuthorDate: 2025-05-21 01:03:13 +0000
Commit:     Konstantin Belousov <k...@freebsd.org>
CommitDate: 2025-06-09 23:47:12 +0000

    ktls: add global generation count
    
    Reviewed by:    jhb, markj
    Sponsored by:   NVidia networking
    Differential revision:  https://reviews.freebsd.org/D50653
---
 sys/kern/uipc_ktls.c | 8 ++++++++
 sys/sys/ktls.h       | 9 +++++++++
 2 files changed, 17 insertions(+)

diff --git a/sys/kern/uipc_ktls.c b/sys/kern/uipc_ktls.c
index 5e9dd254debd..b479ca9c3ed7 100644
--- a/sys/kern/uipc_ktls.c
+++ b/sys/kern/uipc_ktls.c
@@ -595,6 +595,8 @@ start:
        return (error);
 }
 
+uint64_t ktls_glob_gen = 1;
+
 static int
 ktls_create_session(struct socket *so, struct tls_enable *en,
     struct ktls_session **tlsp, int direction)
@@ -819,6 +821,8 @@ ktls_create_session(struct socket *so, struct tls_enable 
*en,
                        arc4rand(tls->params.iv + 8, sizeof(uint64_t), 0);
        }
 
+       atomic_thread_fence_rel();
+       tls->gen = atomic_fetchadd_64(&ktls_glob_gen, 1);
        *tlsp = tls;
        return (0);
 }
@@ -861,6 +865,8 @@ ktls_clone_session(struct ktls_session *tls, int direction)
        memcpy(tls_new->params.cipher_key, tls->params.cipher_key,
            tls->params.cipher_key_len);
 
+       atomic_thread_fence_rel();
+       tls_new->gen = atomic_fetchadd_64(&ktls_glob_gen, 1);
        return (tls_new);
 }
 
@@ -1940,6 +1946,8 @@ ktls_destroy(struct ktls_session *tls)
 
        MPASS(tls->refcount == 0);
 
+       atomic_add_acq_64(&ktls_glob_gen, 1);
+
        inp = tls->inp;
        if (tls->tx) {
                wlocked = INP_WLOCKED(inp);
diff --git a/sys/sys/ktls.h b/sys/sys/ktls.h
index 0e52d643fe3b..8dad53868686 100644
--- a/sys/sys/ktls.h
+++ b/sys/sys/ktls.h
@@ -206,9 +206,12 @@ struct ktls_session {
 
        /* Used to destroy any kTLS session */
        struct task destroy_task;
+
+       uint64_t gen;
 } __aligned(CACHE_LINE_SIZE);
 
 extern unsigned int ktls_ifnet_max_rexmit_pct;
+extern uint64_t ktls_glob_gen;
 
 typedef enum {
        KTLS_MBUF_CRYPTO_ST_MIXED = 0,
@@ -258,5 +261,11 @@ ktls_free(struct ktls_session *tls)
                ktls_destroy(tls);
 }
 
+static inline bool
+ktls_session_genvis(const struct ktls_session *ks, uint64_t gen)
+{
+       return (ks != NULL && ks->gen <= gen);
+}
+
 #endif /* !_KERNEL */
 #endif /* !_SYS_KTLS_H_ */