+static int
+nfp_map_ptr_record(struct nfp_app_bpf *bpf, struct nfp_prog *nfp_prog,
+ struct bpf_map *map)
+{
+ struct nfp_bpf_neutral_map *record;
+ int err;
+
+ /* Map record paths are entered via ndo, update side is protected. */
+ ASSERT_RTNL();
+
+ /* Reuse path - other offloaded program is already tracking this map. */
+ record = rhashtable_lookup_fast(&bpf->maps_neutral, &map,
+ nfp_bpf_maps_neutral_params);
+ if (record) {
+ nfp_prog->map_records[nfp_prog->map_records_cnt++] = record;
+ record->count++;
+ return 0;
+ }
+
+ /* Grab a single ref to the map for our record. The prog destroy ndo
+ * happens after free_used_maps().
+ */
+ map = bpf_map_inc(map, false);
+ if (IS_ERR(map))
+ return PTR_ERR(map);
+
+ record = kmalloc(sizeof(*record), GFP_KERNEL);
+ if (!record) {
+ err = -ENOMEM;
+ goto err_map_put;
+ }
+
+ record->ptr = map;
+ record->count = 1;
+
+ err = rhashtable_insert_fast(&bpf->maps_neutral, &record->l,
+ nfp_bpf_maps_neutral_params);
+ if (err)
+ goto err_free_rec;
+
+ nfp_prog->map_records[nfp_prog->map_records_cnt++] = record;
+
+ return 0;
+
+err_free_rec:
+ kfree(record);
+err_map_put:
+ bpf_map_put(map);
+ return err;
+}
+
+static void
+nfp_map_ptrs_forget(struct nfp_app_bpf *bpf, struct nfp_prog *nfp_prog)
+{
+ bool freed = false;
+ int i;
+
+ ASSERT_RTNL();
+
+ for (i = 0; i < nfp_prog->map_records_cnt; i++) {
+ if (--nfp_prog->map_records[i]->count) {
+ nfp_prog->map_records[i] = NULL;
+ continue;
+ }
+
+ WARN_ON(rhashtable_remove_fast(&bpf->maps_neutral,
+ &nfp_prog->map_records[i]->l,
+ nfp_bpf_maps_neutral_params));
+ freed = true;
+ }
+
+ if (freed) {
+ synchronize_rcu();
+
+ for (i = 0; i < nfp_prog->map_records_cnt; i++)
+ if (nfp_prog->map_records[i]) {
+ bpf_map_put(nfp_prog->map_records[i]->ptr);
+ kfree(nfp_prog->map_records[i]);
+ }
+ }
+
+ kfree(nfp_prog->map_records);
+ nfp_prog->map_records = NULL;
+ nfp_prog->map_records_cnt = 0;
+}
+
+static int
+nfp_map_ptrs_record(struct nfp_app_bpf *bpf, struct nfp_prog *nfp_prog,
+ struct bpf_prog *prog)
+{
+ int i, cnt, err;
+
+ /* Quickly count the maps we will have to remember */
+ cnt = 0;
+ for (i = 0; i < prog->aux->used_map_cnt; i++)
+ if (bpf_map_offload_neutral(prog->aux->used_maps[i]))
+ cnt++;
+ if (!cnt)
+ return 0;
+
+ nfp_prog->map_records = kmalloc_array(cnt,
+ sizeof(nfp_prog->map_records[0]),
+ GFP_KERNEL);
+ if (!nfp_prog->map_records)
+ return -ENOMEM;
+
+ for (i = 0; i < prog->aux->used_map_cnt; i++)
+ if (bpf_map_offload_neutral(prog->aux->used_maps[i])) {
+ err = nfp_map_ptr_record(bpf, nfp_prog,
+ prog->aux->used_maps[i]);
+ if (err) {
+ nfp_map_ptrs_forget(bpf, nfp_prog);
+ return err;
+ }
+ }
+ WARN_ON(cnt != nfp_prog->map_records_cnt);
+
+ return 0;
+}
+