Re: [PATCH bpf-next 1/2] bpf: net: Add SO_DETACH_REUSEPORT_BPF

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Wed, Jun 12, 2019 at 12:08 PM Martin KaFai Lau <kafai@xxxxxx> wrote:
>
> There is SO_ATTACH_REUSEPORT_[CE]BPF but there is no DETACH.
> This patch adds SO_DETACH_REUSEPORT_BPF sockopt.  The same
> sockopt can be used to undo both SO_ATTACH_REUSEPORT_[CE]BPF.
>
> reseport_detach_prog() is added and it is mostly a mirror
> of the existing reuseport_attach_prog().  The differences are,
> it does not call reuseport_alloc() and returns -ENOENT when
> there is no old prog.
>
> Cc: Craig Gallek <kraig@xxxxxxxxxx>
> Signed-off-by: Martin KaFai Lau <kafai@xxxxxx>
> ---
>  arch/alpha/include/uapi/asm/socket.h  |  2 ++
>  arch/mips/include/uapi/asm/socket.h   |  2 ++
>  arch/parisc/include/uapi/asm/socket.h |  2 ++
>  arch/sparc/include/uapi/asm/socket.h  |  2 ++
>  include/net/sock_reuseport.h          |  2 ++
>  include/uapi/asm-generic/socket.h     |  2 ++
>  net/core/sock.c                       |  4 ++++
>  net/core/sock_reuseport.c             | 24 ++++++++++++++++++++++++
>  8 files changed, 40 insertions(+)
>
> diff --git a/arch/alpha/include/uapi/asm/socket.h b/arch/alpha/include/uapi/asm/socket.h
> index 976e89b116e5..de6c4df61082 100644
> --- a/arch/alpha/include/uapi/asm/socket.h
> +++ b/arch/alpha/include/uapi/asm/socket.h
> @@ -122,6 +122,8 @@
>  #define SO_RCVTIMEO_NEW         66
>  #define SO_SNDTIMEO_NEW         67
>
> +#define SO_DETACH_REUSEPORT_BPF 68
> +
>  #if !defined(__KERNEL__)
>
>  #if __BITS_PER_LONG == 64
> diff --git a/arch/mips/include/uapi/asm/socket.h b/arch/mips/include/uapi/asm/socket.h
> index d41765cfbc6e..d0a9ed2ca2d6 100644
> --- a/arch/mips/include/uapi/asm/socket.h
> +++ b/arch/mips/include/uapi/asm/socket.h
> @@ -133,6 +133,8 @@
>  #define SO_RCVTIMEO_NEW         66
>  #define SO_SNDTIMEO_NEW         67
>
> +#define SO_DETACH_REUSEPORT_BPF 68
> +
>  #if !defined(__KERNEL__)
>
>  #if __BITS_PER_LONG == 64
> diff --git a/arch/parisc/include/uapi/asm/socket.h b/arch/parisc/include/uapi/asm/socket.h
> index 66c5dd245ac7..10173c32195e 100644
> --- a/arch/parisc/include/uapi/asm/socket.h
> +++ b/arch/parisc/include/uapi/asm/socket.h
> @@ -114,6 +114,8 @@
>  #define SO_RCVTIMEO_NEW         0x4040
>  #define SO_SNDTIMEO_NEW         0x4041
>
> +#define SO_DETACH_REUSEPORT_BPF 0x4042
> +
>  #if !defined(__KERNEL__)
>
>  #if __BITS_PER_LONG == 64
> diff --git a/arch/sparc/include/uapi/asm/socket.h b/arch/sparc/include/uapi/asm/socket.h
> index 9265a9eece15..1895ac112a24 100644
> --- a/arch/sparc/include/uapi/asm/socket.h
> +++ b/arch/sparc/include/uapi/asm/socket.h
> @@ -115,6 +115,8 @@
>  #define SO_RCVTIMEO_NEW          0x0044
>  #define SO_SNDTIMEO_NEW          0x0045
>
> +#define SO_DETACH_REUSEPORT_BPF  0x0046


Oh, it's so nasty, there is

#define SO_TIMESTAMP_NEW         0x0046

few lines above this, completely out of order. Let's reorder it to
avoid issues like this one.

> +
>  #if !defined(__KERNEL__)
>
>
> diff --git a/include/net/sock_reuseport.h b/include/net/sock_reuseport.h
> index 8a5f70c7cdf2..d9112de85261 100644
> --- a/include/net/sock_reuseport.h
> +++ b/include/net/sock_reuseport.h
> @@ -35,6 +35,8 @@ extern struct sock *reuseport_select_sock(struct sock *sk,
>                                           struct sk_buff *skb,
>                                           int hdr_len);
>  extern int reuseport_attach_prog(struct sock *sk, struct bpf_prog *prog);
> +extern int reuseport_detach_prog(struct sock *sk);
> +
>  int reuseport_get_id(struct sock_reuseport *reuse);
>
>  #endif  /* _SOCK_REUSEPORT_H */
> diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h
> index 8c1391c89171..77f7c1638eb1 100644
> --- a/include/uapi/asm-generic/socket.h
> +++ b/include/uapi/asm-generic/socket.h
> @@ -117,6 +117,8 @@
>  #define SO_RCVTIMEO_NEW         66
>  #define SO_SNDTIMEO_NEW         67
>
> +#define SO_DETACH_REUSEPORT_BPF 68
> +
>  #if !defined(__KERNEL__)
>
>  #if __BITS_PER_LONG == 64 || (defined(__x86_64__) && defined(__ILP32__))
> diff --git a/net/core/sock.c b/net/core/sock.c
> index 75b1c950b49f..06be30737b69 100644
> --- a/net/core/sock.c
> +++ b/net/core/sock.c
> @@ -1045,6 +1045,10 @@ int sock_setsockopt(struct socket *sock, int level, int optname,
>                 }
>                 break;
>
> +       case SO_DETACH_REUSEPORT_BPF:
> +               ret = reuseport_detach_prog(sk);
> +               break;
> +
>         case SO_DETACH_FILTER:
>                 ret = sk_detach_filter(sk);
>                 break;
> diff --git a/net/core/sock_reuseport.c b/net/core/sock_reuseport.c
> index dc4aefdf2a08..e0cb29469fa7 100644
> --- a/net/core/sock_reuseport.c
> +++ b/net/core/sock_reuseport.c
> @@ -332,3 +332,27 @@ int reuseport_attach_prog(struct sock *sk, struct bpf_prog *prog)
>         return 0;
>  }
>  EXPORT_SYMBOL(reuseport_attach_prog);
> +
> +int reuseport_detach_prog(struct sock *sk)
> +{
> +       struct sock_reuseport *reuse;
> +       struct bpf_prog *old_prog;
> +
> +       if (!rcu_access_pointer(sk->sk_reuseport_cb))
> +               return sk->sk_reuseport ? -ENOENT : -EINVAL;
> +
> +       spin_lock_bh(&reuseport_lock);
> +       reuse = rcu_dereference_protected(sk->sk_reuseport_cb,
> +                                         lockdep_is_held(&reuseport_lock));
> +       old_prog = rcu_dereference_protected(reuse->prog,
> +                                            lockdep_is_held(&reuseport_lock));
> +       RCU_INIT_POINTER(reuse->prog, NULL);
> +       spin_unlock_bh(&reuseport_lock);
> +
> +       if (!old_prog)
> +               return -ENOENT;
> +
> +       sk_reuseport_prog_free(old_prog);
> +       return 0;
> +}
> +EXPORT_SYMBOL(reuseport_detach_prog);
> --
> 2.17.1
>



[Index of Archives]     [Linux Samsung SoC]     [Linux Rockchip SoC]     [Linux Actions SoC]     [Linux for Synopsys ARC Processors]     [Linux NFS]     [Linux NILFS]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]


  Powered by Linux