net: sched: cls_flower: implement offload tcf_proto_op

Add the reoffload tcf_proto_op in flower to generate an offload message
for each filter in the given tcf_proto. Call the specified callback with
this new offload message. The function only returns an error if the
callback rejects adding a 'hardware only' rule.

A filter contains a flag to indicate if it is in hardware or not. To
ensure the reoffload function properly maintains this flag, keep a
reference counter for the number of instances of the filter that are in
hardware. Only update the flag when this counter changes from or to 0. Add
a generic helper function to implement this behaviour.

Signed-off-by: John Hurley <john.hurley@netronome.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 18adc91..7432100 100644 (file)
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -336,6 +336,21 @@ static inline void tcf_block_offload_dec(struct tcf_block *block, u32 *flags)
        block->offloadcnt--;
 }
 
+static inline void
+tc_cls_offload_cnt_update(struct tcf_block *block, unsigned int *cnt,
+                         u32 *flags, bool add)
+{
+       if (add) {
+               if (!*cnt)
+                       tcf_block_offload_inc(block, flags);
+               (*cnt)++;
+       } else {
+               (*cnt)--;
+               if (!*cnt)
+                       tcf_block_offload_dec(block, flags);
+       }
+}
+
 static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz)
 {
        struct qdisc_skb_cb *qcb;

diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c
index 9e8b26a..352876b 100644 (file)
--- a/net/sched/cls_flower.c
+++ b/net/sched/cls_flower.c
@@ -87,6 +87,7 @@ struct cls_fl_filter {
        struct list_head list;
        u32 handle;
        u32 flags;
+       unsigned int in_hw_count;
        struct rcu_work rwork;
        struct net_device *hw_dev;
 };
@@ -289,6 +290,7 @@ static int fl_hw_replace_filter(struct tcf_proto *tp,
                fl_hw_destroy_filter(tp, f, NULL);
                return err;
        } else if (err > 0) {
+               f->in_hw_count = err;
                tcf_block_offload_inc(block, &f->flags);
        }
 
@@ -1087,6 +1089,47 @@ skip:
        }
 }
 
+static int fl_reoffload(struct tcf_proto *tp, bool add, tc_setup_cb_t *cb,
+                       void *cb_priv, struct netlink_ext_ack *extack)
+{
+       struct cls_fl_head *head = rtnl_dereference(tp->root);
+       struct tc_cls_flower_offload cls_flower = {};
+       struct tcf_block *block = tp->chain->block;
+       struct fl_flow_mask *mask;
+       struct cls_fl_filter *f;
+       int err;
+
+       list_for_each_entry(mask, &head->masks, list) {
+               list_for_each_entry(f, &mask->filters, list) {
+                       if (tc_skip_hw(f->flags))
+                               continue;
+
+                       tc_cls_common_offload_init(&cls_flower.common, tp,
+                                                  f->flags, extack);
+                       cls_flower.command = add ?
+                               TC_CLSFLOWER_REPLACE : TC_CLSFLOWER_DESTROY;
+                       cls_flower.cookie = (unsigned long)f;
+                       cls_flower.dissector = &mask->dissector;
+                       cls_flower.mask = &f->mkey;
+                       cls_flower.key = &f->key;
+                       cls_flower.exts = &f->exts;
+                       cls_flower.classid = f->res.classid;
+
+                       err = cb(TC_SETUP_CLSFLOWER, &cls_flower, cb_priv);
+                       if (err) {
+                               if (add && tc_skip_sw(f->flags))
+                                       return err;
+                               continue;
+                       }
+
+                       tc_cls_offload_cnt_update(block, &f->in_hw_count,
+                                                 &f->flags, add);
+               }
+       }
+
+       return 0;
+}
+
 static int fl_dump_key_val(struct sk_buff *skb,
                           void *val, int val_type,
                           void *mask, int mask_type, int len)
@@ -1438,6 +1481,7 @@ static struct tcf_proto_ops cls_fl_ops __read_mostly = {
        .change         = fl_change,
        .delete         = fl_delete,
        .walk           = fl_walk,
+       .reoffload      = fl_reoffload,
        .dump           = fl_dump,
        .bind_class     = fl_bind_class,
        .owner          = THIS_MODULE,