nfp: reject binding to shared blocks

TC shared blocks allow multiple qdiscs to be grouped together and filters
shared between them. Currently the chains of filters attached to a block
are only flushed when the block is removed. If a qdisc is removed from a
block but the block still exists, flow del messages are not passed to the
callback registered for that qdisc. For the NFP, this presents the
possibility of rules still existing in hw when they should be removed.

Prevent binding to shared blocks until the kernel can send per qdisc del
messages when block unbinds occur.

tcf_block_shared() was not used outside of the core until now, so also
add an empty implementation for builds with CONFIG_NET_CLS=n.

Fixes: 4861738775d7 ("net: sched: introduce shared filter blocks infrastructure")
Signed-off-by: John Hurley <john.hurley@netronome.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/netronome/nfp/bpf/main.c b/drivers/net/ethernet/netronome/nfp/bpf/main.c
index fcdfb8e7fdeab0b9dcb353f4cd4a7d76370c9817..6b15e3b1195607792ebe93d44ce66523bbf934e2 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/bpf/main.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/main.c
@@ -202,6 +202,9 @@ static int nfp_bpf_setup_tc_block(struct net_device *netdev,
        if (f->binder_type != TCF_BLOCK_BINDER_TYPE_CLSACT_INGRESS)
                return -EOPNOTSUPP;
 
+       if (tcf_block_shared(f->block))
+               return -EOPNOTSUPP;
+
        switch (f->command) {
        case TC_BLOCK_BIND:
                return tcf_block_cb_register(f->block,

diff --git a/drivers/net/ethernet/netronome/nfp/flower/offload.c b/drivers/net/ethernet/netronome/nfp/flower/offload.c
index 477f584f6d28bd9cf5c4f6e1eb1db90596008120..525057bee0ed8978f360d6eeb8293d8a990a0f22 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/flower/offload.c
+++ b/drivers/net/ethernet/netronome/nfp/flower/offload.c
@@ -631,6 +631,9 @@ static int nfp_flower_setup_tc_block(struct net_device *netdev,
        if (f->binder_type != TCF_BLOCK_BINDER_TYPE_CLSACT_INGRESS)
                return -EOPNOTSUPP;
 
+       if (tcf_block_shared(f->block))
+               return -EOPNOTSUPP;
+
        switch (f->command) {
        case TC_BLOCK_BIND:
                return tcf_block_cb_register(f->block,

diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h
index a3c1a2c47cd4bfd868004548cdf1ef7a361fa4c6..20b059574e600e64838b0bdecfaf6a76e6629d4a 100644 (file)
--- a/include/net/pkt_cls.h
+++ b/include/net/pkt_cls.h
@@ -111,6 +111,11 @@ void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q,
 {
 }
 
+static inline bool tcf_block_shared(struct tcf_block *block)
+{
+       return false;
+}
+
 static inline struct Qdisc *tcf_block_q(struct tcf_block *block)
 {
        return NULL;