summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorDavide Caratti <dcaratti@redhat.com>2017-05-18 15:44:37 +0200
committerDavid S. Miller <davem@davemloft.net>2017-05-19 19:21:29 -0400
commit9617813dba5b6c112922c60cd2bc57c6e11ae907 (patch)
treece7dfcb633751f2aaed7fe3b19988aa88f401270
parent6f5b24eed0278136c29c27f2a7b3a2b6a202ac68 (diff)
downloadlinux-9617813dba5b6c112922c60cd2bc57c6e11ae907.tar.bz2
skbuff: add stub to help computing crc32c on SCTP packets
sctp_compute_checksum requires crc32c symbol (provided by libcrc32c), so it can't be used in net core. Like it has been done previously with other symbols (e.g. ipv6_dst_lookup), introduce a stub struct skb_checksum_ops to allow computation of crc32c checksum in net core after sctp.ko (and thus libcrc32c) has been loaded. Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--include/linux/skbuff.h2
-rw-r--r--net/core/skbuff.c26
-rw-r--r--net/sctp/offload.c6
3 files changed, 34 insertions, 0 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 7c0cb2ce8b01..b1f46a0d18e2 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -3076,6 +3076,8 @@ struct skb_checksum_ops {
__wsum (*combine)(__wsum csum, __wsum csum2, int offset, int len);
};
+extern const struct skb_checksum_ops *crc32c_csum_stub __read_mostly;
+
__wsum __skb_checksum(const struct sk_buff *skb, int offset, int len,
__wsum csum, const struct skb_checksum_ops *ops);
__wsum skb_checksum(const struct sk_buff *skb, int offset, int len,
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 346d3e85dfbc..d5c98117cbce 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -2243,6 +2243,32 @@ __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset,
}
EXPORT_SYMBOL(skb_copy_and_csum_bits);
+static __wsum warn_crc32c_csum_update(const void *buff, int len, __wsum sum)
+{
+ net_warn_ratelimited(
+ "%s: attempt to compute crc32c without libcrc32c.ko\n",
+ __func__);
+ return 0;
+}
+
+static __wsum warn_crc32c_csum_combine(__wsum csum, __wsum csum2,
+ int offset, int len)
+{
+ net_warn_ratelimited(
+ "%s: attempt to compute crc32c without libcrc32c.ko\n",
+ __func__);
+ return 0;
+}
+
+static const struct skb_checksum_ops default_crc32c_ops = {
+ .update = warn_crc32c_csum_update,
+ .combine = warn_crc32c_csum_combine,
+};
+
+const struct skb_checksum_ops *crc32c_csum_stub __read_mostly =
+ &default_crc32c_ops;
+EXPORT_SYMBOL(crc32c_csum_stub);
+
/**
* skb_zerocopy_headlen - Calculate headroom needed for skb_zerocopy()
* @from: source buffer
diff --git a/net/sctp/offload.c b/net/sctp/offload.c
index 4f5a2b580aa5..b67198429db5 100644
--- a/net/sctp/offload.c
+++ b/net/sctp/offload.c
@@ -98,6 +98,11 @@ static const struct net_offload sctp6_offload = {
},
};
+static const struct skb_checksum_ops crc32c_csum_ops = {
+ .update = sctp_csum_update,
+ .combine = sctp_csum_combine,
+};
+
int __init sctp_offload_init(void)
{
int ret;
@@ -110,6 +115,7 @@ int __init sctp_offload_init(void)
if (ret)
goto ipv4;
+ crc32c_csum_stub = &crc32c_csum_ops;
return ret;
ipv4: