Classifiers can be used by more than one rule. If there is an existing classifier, use it instead of creating a new one. If duplicate classifiers are created it would artifically limit the number of rules to the classifier limit, which is likely less than the rules limit.
Signed-off-by: Daniel Jurgens <[email protected]> Reviewed-by: Parav Pandit <[email protected]> Reviewed-by: Shahar Shitrit <[email protected]> Reviewed-by: Xuan Zhuo <[email protected]> --- v4: - Fixed typo in commit message - for (int -> for ( v8: - Removed unused num_classifiers. Jason Wang v12: - Clarified comment about destroy_classifier freeing. MST - Renamed the classifier field of virtnet_classifier to obj. MST - Explained why in commit message. MST --- --- drivers/net/virtio_net.c | 51 ++++++++++++++++++++++++++-------------- 1 file changed, 34 insertions(+), 17 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 7600e2383a72..5e49cd78904f 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -32,6 +32,7 @@ #include <uapi/linux/virtio_pci.h> #include <uapi/linux/virtio_net_ff.h> #include <linux/xarray.h> +#include <linux/refcount.h> static int napi_weight = NAPI_POLL_WEIGHT; module_param(napi_weight, int, 0444); @@ -302,7 +303,6 @@ struct virtnet_ff { struct virtio_net_ff_cap_mask_data *ff_mask; struct virtio_net_ff_actions *ff_actions; struct xarray classifiers; - int num_classifiers; struct virtnet_ethtool_ff ethtool; }; @@ -5816,12 +5816,13 @@ struct virtnet_ethtool_rule { /* The classifier struct must be the last field in this struct */ struct virtnet_classifier { size_t size; + refcount_t refcount; u32 id; - struct virtio_net_resource_obj_ff_classifier classifier; + struct virtio_net_resource_obj_ff_classifier obj; }; static_assert(sizeof(struct virtnet_classifier) == - ALIGN(offsetofend(struct virtnet_classifier, classifier), + ALIGN(offsetofend(struct virtnet_classifier, obj), __alignof__(struct virtnet_classifier)), "virtnet_classifier: classifier must be the last member"); @@ -5909,11 +5910,24 @@ static bool validate_mask(const struct virtnet_ff *ff, return false; } -static int setup_classifier(struct virtnet_ff *ff, struct virtnet_classifier *c) +static int setup_classifier(struct virtnet_ff *ff, + struct virtnet_classifier **c) { + struct virtnet_classifier *tmp; + unsigned long i; int err; - err = xa_alloc(&ff->classifiers, &c->id, c, + xa_for_each(&ff->classifiers, i, tmp) { + if ((*c)->size == tmp->size && + !memcmp(&tmp->obj, &(*c)->obj, tmp->size)) { + refcount_inc(&tmp->refcount); + kfree(*c); + *c = tmp; + goto out; + } + } + + err = xa_alloc(&ff->classifiers, &(*c)->id, *c, XA_LIMIT(0, le32_to_cpu(ff->ff_caps->classifiers_limit) - 1), GFP_KERNEL); if (err) @@ -5921,29 +5935,30 @@ static int setup_classifier(struct virtnet_ff *ff, struct virtnet_classifier *c) err = virtio_admin_obj_create(ff->vdev, VIRTIO_NET_RESOURCE_OBJ_FF_CLASSIFIER, - c->id, + (*c)->id, VIRTIO_ADMIN_GROUP_TYPE_SELF, 0, - &c->classifier, - c->size); + &(*c)->obj, + (*c)->size); if (err) goto err_xarray; + refcount_set(&(*c)->refcount, 1); +out: return 0; err_xarray: - xa_erase(&ff->classifiers, c->id); + xa_erase(&ff->classifiers, (*c)->id); return err; } -static void destroy_classifier(struct virtnet_ff *ff, - u32 classifier_id) +static void try_destroy_classifier(struct virtnet_ff *ff, u32 classifier_id) { struct virtnet_classifier *c; c = xa_load(&ff->classifiers, classifier_id); - if (c) { + if (c && refcount_dec_and_test(&c->refcount)) { virtio_admin_obj_destroy(ff->vdev, VIRTIO_NET_RESOURCE_OBJ_FF_CLASSIFIER, c->id, @@ -5967,7 +5982,7 @@ static void destroy_ethtool_rule(struct virtnet_ff *ff, 0); xa_erase(&ff->ethtool.rules, eth_rule->flow_spec.location); - destroy_classifier(ff, eth_rule->classifier_id); + try_destroy_classifier(ff, eth_rule->classifier_id); kfree(eth_rule); } @@ -6139,7 +6154,7 @@ static int build_and_insert(struct virtnet_ff *ff, } c->size = classifier_size; - classifier = &c->classifier; + classifier = &c->obj; classifier->count = num_hdrs; selector = (void *)&classifier->selectors[0]; @@ -6149,14 +6164,16 @@ static int build_and_insert(struct virtnet_ff *ff, if (err) goto err_key; - err = setup_classifier(ff, c); + err = setup_classifier(ff, &c); if (err) goto err_classifier; err = insert_rule(ff, eth_rule, c->id, key, key_size); if (err) { - /* destroy_classifier will free the classifier */ - destroy_classifier(ff, c->id); + /* destroy_classifier release the reference on the classifier + * and free it if needed. + */ + try_destroy_classifier(ff, c->id); goto err_key; } -- 2.50.1
