+static size_t
+devargs_layer_count(const char *s)
+{
+ size_t i = s ? 1 : 0;
+
+ while (s != NULL && s[0] != '\0') {
+ i += s[0] == '/';
+ s++;
+ }
+ return i;
+}
+
+int
+rte_devargs_layers_parse(struct rte_devargs *devargs,
+ const char *devstr)
+{
+ struct {
+ const char *key;
+ const char *str;
+ struct rte_kvargs *kvlist;
+ } layers[] = {
+ { "bus=", NULL, NULL, },
+ { "class=", NULL, NULL, },
+ { "driver=", NULL, NULL, },
+ };
+ struct rte_kvargs_pair *kv = NULL;
+ struct rte_class *cls = NULL;
+ struct rte_bus *bus = NULL;
+ const char *s = devstr;
+ size_t nblayer;
+ size_t i = 0;
+ int ret = 0;
+
+ /* Split each sub-lists. */
+ nblayer = devargs_layer_count(devstr);
+ if (nblayer > RTE_DIM(layers)) {
+ RTE_LOG(ERR, EAL, "Invalid format: too many layers (%zu)\n",
+ nblayer);
+ ret = -E2BIG;
+ goto get_out;
+ }
+
+ /* If the devargs points the devstr
+ * as source data, then it should not allocate
+ * anything and keep referring only to it.
+ */
+ if (devargs->data != devstr) {
+ devargs->data = strdup(devstr);
+ if (devargs->data == NULL) {
+ RTE_LOG(ERR, EAL, "OOM\n");
+ ret = -ENOMEM;
+ goto get_out;
+ }
+ s = devargs->data;
+ }
+
+ while (s != NULL) {
+ if (i >= RTE_DIM(layers)) {
+ RTE_LOG(ERR, EAL, "Unrecognized layer %s\n", s);
+ ret = -EINVAL;
+ goto get_out;
+ }
+ /*
+ * The last layer is free-form.
+ * The "driver" key is not required (but accepted).
+ */
+ if (strncmp(layers[i].key, s, strlen(layers[i].key)) &&
+ i != RTE_DIM(layers) - 1)
+ goto next_layer;
+ layers[i].str = s;
+ layers[i].kvlist = rte_kvargs_parse_delim(s, NULL, "/");
+ if (layers[i].kvlist == NULL) {
+ RTE_LOG(ERR, EAL, "Could not parse %s\n", s);
+ ret = -EINVAL;
+ goto get_out;
+ }
+ s = strchr(s, '/');
+ if (s != NULL)
+ s++;
+next_layer:
+ i++;
+ }
+
+ /* Parse each sub-list. */
+ for (i = 0; i < RTE_DIM(layers); i++) {
+ if (layers[i].kvlist == NULL)
+ continue;
+ kv = &layers[i].kvlist->pairs[0];
+ if (strcmp(kv->key, "bus") == 0) {
+ bus = rte_bus_find_by_name(kv->value);
+ if (bus == NULL) {
+ RTE_LOG(ERR, EAL, "Could not find bus \"%s\"\n",
+ kv->value);
+ ret = -EFAULT;
+ goto get_out;
+ }
+ } else if (strcmp(kv->key, "class") == 0) {
+ cls = rte_class_find_by_name(kv->value);
+ if (cls == NULL) {
+ RTE_LOG(ERR, EAL, "Could not find class \"%s\"\n",
+ kv->value);
+ ret = -EFAULT;
+ goto get_out;
+ }
+ } else if (strcmp(kv->key, "driver") == 0) {
+ /* Ignore */
+ continue;
+ }
+ }
+
+ /* Fill devargs fields. */
+ devargs->bus_str = layers[0].str;
+ devargs->cls_str = layers[1].str;
+ devargs->drv_str = layers[2].str;
+ devargs->bus = bus;
+ devargs->cls = cls;
+
+ /* If we own the data, clean up a bit
+ * the several layers string, to ease
+ * their parsing afterward.
+ */
+ if (devargs->data != devstr) {
+ char *s = (void *)(intptr_t)(devargs->data);
+
+ while ((s = strchr(s, '/'))) {
+ *s = '\0';
+ s++;
+ }
+ }
+
+get_out:
+ for (i = 0; i < RTE_DIM(layers); i++) {
+ if (layers[i].kvlist)
+ rte_kvargs_free(layers[i].kvlist);
+ }
+ if (ret != 0)
+ rte_errno = -ret;
+ return ret;
+}
+