| Message ID | 20201201144418.35045-10-kuniyu@amazon.co.jp |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Socket migration for SO_REUSEPORT. | expand |
On Tue, Dec 01, 2020 at 11:44:16PM +0900, Kuniyuki Iwashima wrote: > We will call sock_reuseport.prog for socket migration in the next commit, > so the eBPF program has to know which listener is closing in order to > select the new listener. > > Currently, we can get a unique ID for each listener in the userspace by > calling bpf_map_lookup_elem() for BPF_MAP_TYPE_REUSEPORT_SOCKARRAY map. > > This patch makes the sk pointer available in sk_reuseport_md so that we can > get the ID by BPF_FUNC_get_socket_cookie() in the eBPF program. > > Link: https://lore.kernel.org/netdev/20201119001154.kapwihc2plp4f7zc@kafai-mbp.dhcp.thefacebook.com/ > Suggested-by: Martin KaFai Lau <kafai@fb.com> > Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp> > --- > include/uapi/linux/bpf.h | 8 ++++++++ > net/core/filter.c | 12 +++++++++++- > tools/include/uapi/linux/bpf.h | 8 ++++++++ > 3 files changed, 27 insertions(+), 1 deletion(-) > > diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h > index efe342bf3dbc..3e9b8bd42b4e 100644 > --- a/include/uapi/linux/bpf.h > +++ b/include/uapi/linux/bpf.h > @@ -1650,6 +1650,13 @@ union bpf_attr { > * A 8-byte long non-decreasing number on success, or 0 if the > * socket field is missing inside *skb*. > * > + * u64 bpf_get_socket_cookie(struct bpf_sock *sk) > + * Description > + * Equivalent to bpf_get_socket_cookie() helper that accepts > + * *skb*, but gets socket from **struct bpf_sock** context. > + * Return > + * A 8-byte long non-decreasing number. > + * > * u64 bpf_get_socket_cookie(struct bpf_sock_addr *ctx) > * Description > * Equivalent to bpf_get_socket_cookie() helper that accepts > @@ -4420,6 +4427,7 @@ struct sk_reuseport_md { > __u32 bind_inany; /* Is sock bound to an INANY address? */ > __u32 hash; /* A hash of the packet 4 tuples */ > __u8 migration; /* Migration type */ > + __bpf_md_ptr(struct bpf_sock *, sk); /* current listening socket */ > }; > > #define BPF_TAG_SIZE 8 > diff --git a/net/core/filter.c b/net/core/filter.c > index 0a0634787bb4..1059d31847ef 100644 > --- a/net/core/filter.c > +++ b/net/core/filter.c > @@ -4628,7 +4628,7 @@ static const struct bpf_func_proto bpf_get_socket_cookie_sock_proto = { > .func = bpf_get_socket_cookie_sock, > .gpl_only = false, > .ret_type = RET_INTEGER, > - .arg1_type = ARG_PTR_TO_CTX, > + .arg1_type = ARG_PTR_TO_SOCKET, This will break existing bpf prog (BPF_PROG_TYPE_CGROUP_SOCK) using this proto. A new proto is needed and there is an on-going patch doing this [0]. [0]: https://lore.kernel.org/bpf/20201203213330.1657666-1-revest@google.com/
I'm sending this mail just for logging because I failed to send mails only to LKML, netdev, and bpf yesterday. From: Martin KaFai Lau <kafai@fb.com> Date: Fri, 4 Dec 2020 11:58:07 -0800 > On Tue, Dec 01, 2020 at 11:44:16PM +0900, Kuniyuki Iwashima wrote: > > We will call sock_reuseport.prog for socket migration in the next commit, > > so the eBPF program has to know which listener is closing in order to > > select the new listener. > > > > Currently, we can get a unique ID for each listener in the userspace by > > calling bpf_map_lookup_elem() for BPF_MAP_TYPE_REUSEPORT_SOCKARRAY map. > > > > This patch makes the sk pointer available in sk_reuseport_md so that we can > > get the ID by BPF_FUNC_get_socket_cookie() in the eBPF program. > > > > Link: https://lore.kernel.org/netdev/20201119001154.kapwihc2plp4f7zc@kafai-mbp.dhcp.thefacebook.com/ > > Suggested-by: Martin KaFai Lau <kafai@fb.com> > > Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp> > > --- > > include/uapi/linux/bpf.h | 8 ++++++++ > > net/core/filter.c | 12 +++++++++++- > > tools/include/uapi/linux/bpf.h | 8 ++++++++ > > 3 files changed, 27 insertions(+), 1 deletion(-) > > > > diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h > > index efe342bf3dbc..3e9b8bd42b4e 100644 > > --- a/include/uapi/linux/bpf.h > > +++ b/include/uapi/linux/bpf.h > > @@ -1650,6 +1650,13 @@ union bpf_attr { > > * A 8-byte long non-decreasing number on success, or 0 if the > > * socket field is missing inside *skb*. > > * > > + * u64 bpf_get_socket_cookie(struct bpf_sock *sk) > > + * Description > > + * Equivalent to bpf_get_socket_cookie() helper that accepts > > + * *skb*, but gets socket from **struct bpf_sock** context. > > + * Return > > + * A 8-byte long non-decreasing number. > > + * > > * u64 bpf_get_socket_cookie(struct bpf_sock_addr *ctx) > > * Description > > * Equivalent to bpf_get_socket_cookie() helper that accepts > > @@ -4420,6 +4427,7 @@ struct sk_reuseport_md { > > __u32 bind_inany; /* Is sock bound to an INANY address? */ > > __u32 hash; /* A hash of the packet 4 tuples */ > > __u8 migration; /* Migration type */ > > + __bpf_md_ptr(struct bpf_sock *, sk); /* current listening socket */ > > }; > > > > #define BPF_TAG_SIZE 8 > > diff --git a/net/core/filter.c b/net/core/filter.c > > index 0a0634787bb4..1059d31847ef 100644 > > --- a/net/core/filter.c > > +++ b/net/core/filter.c > > @@ -4628,7 +4628,7 @@ static const struct bpf_func_proto bpf_get_socket_cookie_sock_proto = { > > .func = bpf_get_socket_cookie_sock, > > .gpl_only = false, > > .ret_type = RET_INTEGER, > > - .arg1_type = ARG_PTR_TO_CTX, > > + .arg1_type = ARG_PTR_TO_SOCKET, > This will break existing bpf prog (BPF_PROG_TYPE_CGROUP_SOCK) > using this proto. A new proto is needed and there is > an on-going patch doing this [0]. > > [0]: https://lore.kernel.org/bpf/20201203213330.1657666-1-revest@google.com/ Thank you for notifying me of this patch! I will define another proto, but may drop the part if the above patch is already merged then.
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index efe342bf3dbc..3e9b8bd42b4e 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -1650,6 +1650,13 @@ union bpf_attr { * A 8-byte long non-decreasing number on success, or 0 if the * socket field is missing inside *skb*. * + * u64 bpf_get_socket_cookie(struct bpf_sock *sk) + * Description + * Equivalent to bpf_get_socket_cookie() helper that accepts + * *skb*, but gets socket from **struct bpf_sock** context. + * Return + * A 8-byte long non-decreasing number. + * * u64 bpf_get_socket_cookie(struct bpf_sock_addr *ctx) * Description * Equivalent to bpf_get_socket_cookie() helper that accepts @@ -4420,6 +4427,7 @@ struct sk_reuseport_md { __u32 bind_inany; /* Is sock bound to an INANY address? */ __u32 hash; /* A hash of the packet 4 tuples */ __u8 migration; /* Migration type */ + __bpf_md_ptr(struct bpf_sock *, sk); /* current listening socket */ }; #define BPF_TAG_SIZE 8 diff --git a/net/core/filter.c b/net/core/filter.c index 0a0634787bb4..1059d31847ef 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -4628,7 +4628,7 @@ static const struct bpf_func_proto bpf_get_socket_cookie_sock_proto = { .func = bpf_get_socket_cookie_sock, .gpl_only = false, .ret_type = RET_INTEGER, - .arg1_type = ARG_PTR_TO_CTX, + .arg1_type = ARG_PTR_TO_SOCKET, }; BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx) @@ -9982,6 +9982,8 @@ sk_reuseport_func_proto(enum bpf_func_id func_id, return &sk_reuseport_load_bytes_proto; case BPF_FUNC_skb_load_bytes_relative: return &sk_reuseport_load_bytes_relative_proto; + case BPF_FUNC_get_socket_cookie: + return &bpf_get_socket_cookie_sock_proto; default: return bpf_base_func_proto(func_id); } @@ -10015,6 +10017,10 @@ sk_reuseport_is_valid_access(int off, int size, return prog->expected_attach_type == BPF_SK_REUSEPORT_SELECT_OR_MIGRATE && size == sizeof(__u8); + case offsetof(struct sk_reuseport_md, sk): + info->reg_type = PTR_TO_SOCKET; + return size == sizeof(__u64); + /* Fields that allow narrowing */ case bpf_ctx_range(struct sk_reuseport_md, eth_protocol): if (size < sizeof_field(struct sk_buff, protocol)) @@ -10091,6 +10097,10 @@ static u32 sk_reuseport_convert_ctx_access(enum bpf_access_type type, case offsetof(struct sk_reuseport_md, migration): SK_REUSEPORT_LOAD_FIELD(migration); break; + + case offsetof(struct sk_reuseport_md, sk): + SK_REUSEPORT_LOAD_FIELD(sk); + break; } return insn - insn_buf; diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index efe342bf3dbc..3e9b8bd42b4e 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -1650,6 +1650,13 @@ union bpf_attr { * A 8-byte long non-decreasing number on success, or 0 if the * socket field is missing inside *skb*. * + * u64 bpf_get_socket_cookie(struct bpf_sock *sk) + * Description + * Equivalent to bpf_get_socket_cookie() helper that accepts + * *skb*, but gets socket from **struct bpf_sock** context. + * Return + * A 8-byte long non-decreasing number. + * * u64 bpf_get_socket_cookie(struct bpf_sock_addr *ctx) * Description * Equivalent to bpf_get_socket_cookie() helper that accepts @@ -4420,6 +4427,7 @@ struct sk_reuseport_md { __u32 bind_inany; /* Is sock bound to an INANY address? */ __u32 hash; /* A hash of the packet 4 tuples */ __u8 migration; /* Migration type */ + __bpf_md_ptr(struct bpf_sock *, sk); /* current listening socket */ }; #define BPF_TAG_SIZE 8
We will call sock_reuseport.prog for socket migration in the next commit, so the eBPF program has to know which listener is closing in order to select the new listener. Currently, we can get a unique ID for each listener in the userspace by calling bpf_map_lookup_elem() for BPF_MAP_TYPE_REUSEPORT_SOCKARRAY map. This patch makes the sk pointer available in sk_reuseport_md so that we can get the ID by BPF_FUNC_get_socket_cookie() in the eBPF program. Link: https://lore.kernel.org/netdev/20201119001154.kapwihc2plp4f7zc@kafai-mbp.dhcp.thefacebook.com/ Suggested-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp> --- include/uapi/linux/bpf.h | 8 ++++++++ net/core/filter.c | 12 +++++++++++- tools/include/uapi/linux/bpf.h | 8 ++++++++ 3 files changed, 27 insertions(+), 1 deletion(-)