diff mbox series

[bpf-next,08/19] udp: implement ->read_sock() for sockmap

Message ID 20210203041636.38555-9-xiyou.wangcong@gmail.com (mailing list archive)
State Changes Requested
Delegated to: BPF
Headers show
Series sock_map: add non-TCP and cross-protocol support | expand

Checks

Context Check Description
netdev/cover_letter success Link
netdev/fixes_present success Link
netdev/patch_count fail Series longer than 15 patches
netdev/tree_selection success Clearly marked for bpf-next
netdev/subject_prefix success Link
netdev/cc_maintainers warning 9 maintainers not CCed: davem@davemloft.net songliubraving@fb.com andrii@kernel.org yoshfuji@linux-ipv6.org kpsingh@kernel.org ast@kernel.org kuba@kernel.org kafai@fb.com yhs@fb.com
netdev/source_inline success Was 0 now: 0
netdev/verify_signedoff success Link
netdev/module_param success Was 0 now: 0
netdev/build_32bit fail Errors and warnings before: 292 this patch: 292
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/verify_fixes success Link
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 55 lines checked
netdev/build_allmodconfig_warn fail Errors and warnings before: 400 this patch: 400
netdev/header_inline success Link
netdev/stable success Stable not CCed

Commit Message

Cong Wang Feb. 3, 2021, 4:16 a.m. UTC
From: Cong Wang <cong.wang@bytedance.com>

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jakub Sitnicki <jakub@cloudflare.com>
Cc: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
---
 include/net/udp.h  |  2 ++
 net/ipv4/af_inet.c |  1 +
 net/ipv4/udp.c     | 34 ++++++++++++++++++++++++++++++++++
 3 files changed, 37 insertions(+)

Comments

Lorenz Bauer Feb. 8, 2021, 9:48 a.m. UTC | #1
On Wed, 3 Feb 2021 at 04:17, Cong Wang <xiyou.wangcong@gmail.com> wrote:
>
> From: Cong Wang <cong.wang@bytedance.com>
>
> Cc: John Fastabend <john.fastabend@gmail.com>
> Cc: Daniel Borkmann <daniel@iogearbox.net>
> Cc: Jakub Sitnicki <jakub@cloudflare.com>
> Cc: Lorenz Bauer <lmb@cloudflare.com>
> Signed-off-by: Cong Wang <cong.wang@bytedance.com>
> ---
>  include/net/udp.h  |  2 ++
>  net/ipv4/af_inet.c |  1 +
>  net/ipv4/udp.c     | 34 ++++++++++++++++++++++++++++++++++
>  3 files changed, 37 insertions(+)
>
> diff --git a/include/net/udp.h b/include/net/udp.h
> index 13f9354dbd3e..b6b75cabf4e4 100644
> --- a/include/net/udp.h
> +++ b/include/net/udp.h
> @@ -327,6 +327,8 @@ struct sock *__udp6_lib_lookup(struct net *net,
>                                struct sk_buff *skb);
>  struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb,
>                                  __be16 sport, __be16 dport);
> +int udp_read_sock(struct sock *sk, read_descriptor_t *desc,
> +                 sk_read_actor_t recv_actor);
>
>  /* UDP uses skb->dev_scratch to cache as much information as possible and avoid
>   * possibly multiple cache miss on dequeue()
> diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
> index d184d9379a92..4a4c6d3d2786 100644
> --- a/net/ipv4/af_inet.c
> +++ b/net/ipv4/af_inet.c
> @@ -1072,6 +1072,7 @@ const struct proto_ops inet_dgram_ops = {
>         .getsockopt        = sock_common_getsockopt,
>         .sendmsg           = inet_sendmsg,
>         .sendmsg_locked    = udp_sendmsg_locked,
> +       .read_sock         = udp_read_sock,
>         .recvmsg           = inet_recvmsg,
>         .mmap              = sock_no_mmap,
>         .sendpage          = inet_sendpage,
> diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
> index 635e1e8b2968..6dffbcec0b51 100644
> --- a/net/ipv4/udp.c
> +++ b/net/ipv4/udp.c
> @@ -1792,6 +1792,40 @@ struct sk_buff *__skb_recv_udp(struct sock *sk, unsigned int flags,
>  }
>  EXPORT_SYMBOL(__skb_recv_udp);
>
> +int udp_read_sock(struct sock *sk, read_descriptor_t *desc,
> +                 sk_read_actor_t recv_actor)
> +{
> +       struct sk_buff *skb;
> +       int copied = 0, err;
> +
> +       while (1) {
> +               int offset = 0;
> +
> +               skb = __skb_recv_udp(sk, 0, 1, &offset, &err);

Seems like err isn't used outside of the loop, is that on purpose? If
yes, how about moving the declaration of err to be with offset. Maybe
rename to ignored?

> +               if (!skb)
> +                       break;
> +               if (offset < skb->len) {
> +                       int used;
> +                       size_t len;
> +
> +                       len = skb->len - offset;
> +                       used = recv_actor(desc, skb, offset, len);
> +                       if (used <= 0) {
> +                               if (!copied)
> +                                       copied = used;
> +                               break;
> +                       } else if (used <= len) {

In which case can used be > len?


> +                               copied += used;
> +                               offset += used;
> +                       }
> +               }
> +               if (!desc->count)
> +                       break;
> +       }
> +
> +       return copied;
> +}
> +
>  /*
>   *     This should be easy, if there is something there we
>   *     return it, otherwise we block.
> --
> 2.25.1
>


--
Lorenz Bauer  |  Systems Engineer
6th Floor, County Hall/The Riverside Building, SE1 7PB, UK

www.cloudflare.com
Cong Wang Feb. 9, 2021, 1:35 a.m. UTC | #2
On Mon, Feb 8, 2021 at 1:48 AM Lorenz Bauer <lmb@cloudflare.com> wrote:
>
> On Wed, 3 Feb 2021 at 04:17, Cong Wang <xiyou.wangcong@gmail.com> wrote:
> >
> > From: Cong Wang <cong.wang@bytedance.com>
> >
> > Cc: John Fastabend <john.fastabend@gmail.com>
> > Cc: Daniel Borkmann <daniel@iogearbox.net>
> > Cc: Jakub Sitnicki <jakub@cloudflare.com>
> > Cc: Lorenz Bauer <lmb@cloudflare.com>
> > Signed-off-by: Cong Wang <cong.wang@bytedance.com>
> > ---
> >  include/net/udp.h  |  2 ++
> >  net/ipv4/af_inet.c |  1 +
> >  net/ipv4/udp.c     | 34 ++++++++++++++++++++++++++++++++++
> >  3 files changed, 37 insertions(+)
> >
> > diff --git a/include/net/udp.h b/include/net/udp.h
> > index 13f9354dbd3e..b6b75cabf4e4 100644
> > --- a/include/net/udp.h
> > +++ b/include/net/udp.h
> > @@ -327,6 +327,8 @@ struct sock *__udp6_lib_lookup(struct net *net,
> >                                struct sk_buff *skb);
> >  struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb,
> >                                  __be16 sport, __be16 dport);
> > +int udp_read_sock(struct sock *sk, read_descriptor_t *desc,
> > +                 sk_read_actor_t recv_actor);
> >
> >  /* UDP uses skb->dev_scratch to cache as much information as possible and avoid
> >   * possibly multiple cache miss on dequeue()
> > diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
> > index d184d9379a92..4a4c6d3d2786 100644
> > --- a/net/ipv4/af_inet.c
> > +++ b/net/ipv4/af_inet.c
> > @@ -1072,6 +1072,7 @@ const struct proto_ops inet_dgram_ops = {
> >         .getsockopt        = sock_common_getsockopt,
> >         .sendmsg           = inet_sendmsg,
> >         .sendmsg_locked    = udp_sendmsg_locked,
> > +       .read_sock         = udp_read_sock,
> >         .recvmsg           = inet_recvmsg,
> >         .mmap              = sock_no_mmap,
> >         .sendpage          = inet_sendpage,
> > diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
> > index 635e1e8b2968..6dffbcec0b51 100644
> > --- a/net/ipv4/udp.c
> > +++ b/net/ipv4/udp.c
> > @@ -1792,6 +1792,40 @@ struct sk_buff *__skb_recv_udp(struct sock *sk, unsigned int flags,
> >  }
> >  EXPORT_SYMBOL(__skb_recv_udp);
> >
> > +int udp_read_sock(struct sock *sk, read_descriptor_t *desc,
> > +                 sk_read_actor_t recv_actor)
> > +{
> > +       struct sk_buff *skb;
> > +       int copied = 0, err;
> > +
> > +       while (1) {
> > +               int offset = 0;
> > +
> > +               skb = __skb_recv_udp(sk, 0, 1, &offset, &err);
>
> Seems like err isn't used outside of the loop, is that on purpose? If
> yes, how about moving the declaration of err to be with offset. Maybe
> rename to ignored?

It should be moved inside the loop.

>
> > +               if (!skb)
> > +                       break;
> > +               if (offset < skb->len) {
> > +                       int used;
> > +                       size_t len;
> > +
> > +                       len = skb->len - offset;
> > +                       used = recv_actor(desc, skb, offset, len);
> > +                       if (used <= 0) {
> > +                               if (!copied)
> > +                                       copied = used;
> > +                               break;
> > +                       } else if (used <= len) {
>
> In which case can used be > len?

I think in splice() case it could return a larger value than 'len', but
UDP does not support splice() even after this patchset. I can change
it to 'else', or just leave it as it is, in case we will add splice() support in
the future.

Thanks.
diff mbox series

Patch

diff --git a/include/net/udp.h b/include/net/udp.h
index 13f9354dbd3e..b6b75cabf4e4 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h
@@ -327,6 +327,8 @@  struct sock *__udp6_lib_lookup(struct net *net,
 			       struct sk_buff *skb);
 struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb,
 				 __be16 sport, __be16 dport);
+int udp_read_sock(struct sock *sk, read_descriptor_t *desc,
+		  sk_read_actor_t recv_actor);
 
 /* UDP uses skb->dev_scratch to cache as much information as possible and avoid
  * possibly multiple cache miss on dequeue()
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index d184d9379a92..4a4c6d3d2786 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1072,6 +1072,7 @@  const struct proto_ops inet_dgram_ops = {
 	.getsockopt	   = sock_common_getsockopt,
 	.sendmsg	   = inet_sendmsg,
 	.sendmsg_locked    = udp_sendmsg_locked,
+	.read_sock	   = udp_read_sock,
 	.recvmsg	   = inet_recvmsg,
 	.mmap		   = sock_no_mmap,
 	.sendpage	   = inet_sendpage,
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 635e1e8b2968..6dffbcec0b51 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1792,6 +1792,40 @@  struct sk_buff *__skb_recv_udp(struct sock *sk, unsigned int flags,
 }
 EXPORT_SYMBOL(__skb_recv_udp);
 
+int udp_read_sock(struct sock *sk, read_descriptor_t *desc,
+		  sk_read_actor_t recv_actor)
+{
+	struct sk_buff *skb;
+	int copied = 0, err;
+
+	while (1) {
+		int offset = 0;
+
+		skb = __skb_recv_udp(sk, 0, 1, &offset, &err);
+		if (!skb)
+			break;
+		if (offset < skb->len) {
+			int used;
+			size_t len;
+
+			len = skb->len - offset;
+			used = recv_actor(desc, skb, offset, len);
+			if (used <= 0) {
+				if (!copied)
+					copied = used;
+				break;
+			} else if (used <= len) {
+				copied += used;
+				offset += used;
+			}
+		}
+		if (!desc->count)
+			break;
+	}
+
+	return copied;
+}
+
 /*
  * 	This should be easy, if there is something there we
  * 	return it, otherwise we block.