Allow grouping multiple leaves shaper under the given root. The root and the leaves shapers are created, if needed, otherwise the existing shapers are re-linked as requested.
Try hard to pre-allocated the needed resources, to avoid non trivial H/W configuration rollbacks in case of any failure. Signed-off-by: Paolo Abeni <[email protected]> --- v4 -> v5: - replace net_device* with binding* in most helpers - factor out net_shaper_fill_binding() helper for re-use in later patch - move most sanity check at parse time and use NL_SET_BAD_ATTR - reused net_shaper_fill_handle() in net_shaper_group_send_reply() instead of open-coding it. v3 -> v4: - cleanup left-over scope node shaper after re-link, as needed - add locking - separate arguments for shaper handle RFC v2 -> RFC v3: - dev_put() -> netdev_put() --- net/shaper/shaper.c | 348 +++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 346 insertions(+), 2 deletions(-) diff --git a/net/shaper/shaper.c b/net/shaper/shaper.c index a58bdd2ec013..f5e8464b8408 100644 --- a/net/shaper/shaper.c +++ b/net/shaper/shaper.c @@ -72,6 +72,24 @@ net_shaper_binding_ops(struct net_shaper_binding *binding) return NULL; } +/* Count the number of [multi] attributes of the given type. */ +static int net_shaper_list_len(struct genl_info *info, int type) +{ + struct nlattr *attr; + int rem, cnt = 0; + + nla_for_each_attr_type(attr, type, genlmsg_data(info->genlhdr), + genlmsg_len(info->genlhdr), rem) + cnt++; + return cnt; +} + +static int net_shaper_handle_size(void) +{ + return nla_total_size(nla_total_size(sizeof(u32)) + + nla_total_size(sizeof(u32))); +} + static int net_shaper_fill_binding(struct sk_buff *msg, const struct net_shaper_binding *binding, u32 type) @@ -359,6 +377,29 @@ static void net_shaper_cache_commit(struct net_shaper_binding *binding, xa_unlock(&data->shapers); } +/* Rollback all the tentative inserts from the shaper cache. */ +static void net_shaper_cache_rollback(struct net_shaper_binding *binding) +{ + struct net_shaper_data *data = net_shaper_binding_data(binding); + struct net_shaper_handle handle; + struct net_shaper_info *cur; + unsigned long index; + + if (!data) + return; + + xa_lock(&data->shapers); + xa_for_each_marked(&data->shapers, index, cur, + NET_SHAPER_CACHE_NOT_VALID) { + net_shaper_index_to_handle(index, &handle); + if (handle.scope == NET_SHAPER_SCOPE_NODE) + idr_remove(&data->node_ids, handle.id); + __xa_erase(&data->shapers, index); + kfree(cur); + } + xa_unlock(&data->shapers); +} + static int net_shaper_parse_handle(const struct nlattr *attr, const struct genl_info *info, struct net_shaper_handle *handle) @@ -455,6 +496,7 @@ static int net_shaper_parse_info(struct net_shaper_binding *binding, static int net_shaper_parse_info_nest(struct net_shaper_binding *binding, const struct nlattr *attr, const struct genl_info *info, + enum net_shaper_scope expected_scope, struct net_shaper_handle *handle, struct net_shaper_info *shaper) { @@ -471,11 +513,62 @@ static int net_shaper_parse_info_nest(struct net_shaper_binding *binding, if (ret < 0) return ret; + if (expected_scope != NET_SHAPER_SCOPE_UNSPEC && + handle->scope != expected_scope) { + NL_SET_BAD_ATTR(info->extack, tb[NET_SHAPER_A_HANDLE]); + return -EINVAL; + } + if (!cached) net_shaper_default_parent(handle, &shaper->parent); return 0; } +/* Alike net_parse_shaper_info(), but additionally allow the user specifying + * the shaper's parent handle. + */ +static int net_shaper_parse_node(struct net_shaper_binding *binding, + const struct nlattr *attr, + const struct genl_info *info, + struct net_shaper_handle *handle, + struct net_shaper_info *shaper) +{ + struct nlattr *tb[NET_SHAPER_A_PARENT + 1]; + bool cached; + int ret; + + ret = nla_parse_nested(tb, NET_SHAPER_A_PARENT, attr, + net_shaper_node_info_nl_policy, + info->extack); + if (ret < 0) + return ret; + + ret = net_shaper_parse_info(binding, tb, info, handle, shaper, + &cached); + if (ret) + return ret; + + if (handle->scope != NET_SHAPER_SCOPE_NODE && + handle->scope != NET_SHAPER_SCOPE_NETDEV) { + NL_SET_BAD_ATTR(info->extack, tb[NET_SHAPER_A_HANDLE]); + return -EINVAL; + } + + if (tb[NET_SHAPER_A_PARENT]) { + ret = net_shaper_parse_handle(tb[NET_SHAPER_A_PARENT], info, + &shaper->parent); + if (ret) + return ret; + + if (shaper->parent.scope != NET_SHAPER_SCOPE_NODE && + shaper->parent.scope != NET_SHAPER_SCOPE_NETDEV) { + NL_SET_BAD_ATTR(info->extack, tb[NET_SHAPER_A_PARENT]); + return -EINVAL; + } + } + return 0; +} + static int net_shaper_generic_pre(struct genl_info *info, int type) { struct net_shaper_nl_ctx *ctx; @@ -657,8 +750,9 @@ int net_shaper_nl_set_doit(struct sk_buff *skb, struct genl_info *info) binding = net_shaper_binding_from_ctx(info->user_ptr[0]); attr = info->attrs[NET_SHAPER_A_SHAPER]; - ret = net_shaper_parse_info_nest(binding, attr, info, &handle, - &shaper); + ret = net_shaper_parse_info_nest(binding, attr, info, + NET_SHAPER_SCOPE_UNSPEC, + &handle, &shaper); if (ret) return ret; @@ -704,6 +798,100 @@ static int __net_shaper_delete(struct net_shaper_binding *binding, return 0; } +static int __net_shaper_group(struct net_shaper_binding *binding, + int leaves_count, + const struct net_shaper_handle *leaves_handles, + struct net_shaper_info *leaves, + struct net_shaper_handle *node_handle, + struct net_shaper_info *node, + struct netlink_ext_ack *extack) +{ + const struct net_shaper_ops *ops = net_shaper_binding_ops(binding); + struct net_shaper_info *parent = NULL; + struct net_shaper_handle leaf_handle; + int i, ret; + + if (node_handle->scope == NET_SHAPER_SCOPE_NODE) { + if (node_handle->id != NET_SHAPER_ID_UNSPEC && + !net_shaper_cache_lookup(binding, node_handle)) { + NL_SET_ERR_MSG_FMT(extack, "Node shaper %d:%d does not exists", + node_handle->scope, node_handle->id); + return -ENOENT; + } + + /* When unspecified, the node parent scope is inherited from + * the leaves. + */ + if (node->parent.scope == NET_SHAPER_SCOPE_UNSPEC) { + for (i = 1; i < leaves_count; ++i) { + if (leaves[i].parent.scope != + leaves[0].parent.scope || + leaves[i].parent.id != + leaves[0].parent.id) { + NL_SET_ERR_MSG_FMT(extack, "All the leaves shapers must have the same old parent"); + return -EINVAL; + } + } + + if (leaves_count > 0) + node->parent = leaves[0].parent; + } + + } else { + net_shaper_default_parent(node_handle, &node->parent); + } + + if (node->parent.scope == NET_SHAPER_SCOPE_NODE) { + parent = net_shaper_cache_lookup(binding, &node->parent); + if (!parent) { + NL_SET_ERR_MSG_FMT(extack, "Node parent shaper %d:%d does not exists", + node->parent.scope, node->parent.id); + return -ENOENT; + } + } + + /* For newly created node scope shaper, the following will update + * the handle, due to id allocation. + */ + ret = net_shaper_cache_pre_insert(binding, node_handle, extack); + if (ret) + return ret; + + for (i = 0; i < leaves_count; ++i) { + leaf_handle = leaves_handles[i]; + + ret = net_shaper_cache_pre_insert(binding, &leaf_handle, + extack); + if (ret) + goto rollback; + + if (leaves[i].parent.scope == node_handle->scope && + leaves[i].parent.id == node_handle->id) + continue; + + /* The leaves shapers will be nested to the node, update the + * linking accordingly. + */ + leaves[i].parent = *node_handle; + node->leaves++; + } + + ret = ops->group(binding, leaves_count, leaves_handles, leaves, + node_handle, node, extack); + if (ret < 0) + goto rollback; + + if (parent) + parent->leaves++; + net_shaper_cache_commit(binding, 1, node_handle, node); + net_shaper_cache_commit(binding, leaves_count, leaves_handles, leaves); + return 0; + +rollback: + net_shaper_cache_rollback(binding); + return ret; +} + static int net_shaper_delete(struct net_shaper_binding *binding, const struct net_shaper_handle *handle, struct netlink_ext_ack *extack) @@ -756,6 +944,162 @@ int net_shaper_nl_delete_doit(struct sk_buff *skb, struct genl_info *info) return net_shaper_delete(binding, &handle, info->extack); } +/* Update the H/W and on success update the local cache, too */ +static int net_shaper_group(struct net_shaper_binding *binding, + int leaves_count, + const struct net_shaper_handle *leaves_handles, + struct net_shaper_info *leaves, + struct net_shaper_handle *node_handle, + struct net_shaper_info *node, + struct netlink_ext_ack *extack) +{ + struct net_shaper_data *data = net_shaper_cache_init(binding, extack); + struct net_shaper_handle *old_nodes; + int i, ret, old_nodes_count = 0; + + if (!data) + return -ENOMEM; + + old_nodes = kcalloc(leaves_count, sizeof(struct net_shaper_handle), + GFP_KERNEL); + if (!old_nodes) + return -ENOMEM; + + for (i = 0; i < leaves_count; i++) + if (leaves[i].parent.scope == NET_SHAPER_SCOPE_NODE && + (leaves[i].parent.scope != node_handle->scope || + leaves[i].parent.id != node_handle->id)) + old_nodes[old_nodes_count++] = leaves[i].parent; + + mutex_lock(&data->lock); + ret = __net_shaper_group(binding, leaves_count, leaves_handles, + leaves, node_handle, node, extack); + + /* Check if we need to delete any NODE left alone by the new leaves + * linkage. + */ + for (i = 0; i < old_nodes_count; ++i) { + node = net_shaper_cache_lookup(binding, &old_nodes[i]); + if (!node) + continue; + + if (--node->leaves > 0) + continue; + + /* Errors here are not fatal: the grouping operation is + * completed, and user-space can still explicitly clean-up + * left-over nodes. + */ + __net_shaper_delete(binding, &old_nodes[i], node, extack); + } + + mutex_unlock(&data->lock); + + kfree(old_nodes); + return ret; +} + +static int net_shaper_group_send_reply(struct genl_info *info, + struct net_shaper_handle *handle) +{ + struct net_shaper_binding *binding = info->user_ptr[0]; + struct sk_buff *msg; + int ret = -EMSGSIZE; + void *hdr; + + /* Prepare the msg reply in advance, to avoid device operation + * rollback. + */ + msg = genlmsg_new(net_shaper_handle_size(), GFP_KERNEL); + if (!msg) + return ret; + + hdr = genlmsg_iput(msg, info); + if (!hdr) + goto free_msg; + + if (net_shaper_fill_binding(msg, binding, NET_SHAPER_A_IFINDEX)) + goto free_msg; + + if (net_shaper_fill_handle(msg, handle, NET_SHAPER_A_HANDLE)) + goto free_msg; + + genlmsg_end(msg, hdr); + + ret = genlmsg_reply(msg, info); + if (ret) + goto free_msg; + + return ret; + +free_msg: + nlmsg_free(msg); + return ret; +} + +int net_shaper_nl_group_doit(struct sk_buff *skb, struct genl_info *info) +{ + struct net_shaper_handle *leaves_handles, node_handle; + struct net_shaper_info *leaves, node; + struct net_shaper_binding *binding; + int i, ret, rem, leaves_count; + struct nlattr *attr; + + if (GENL_REQ_ATTR_CHECK(info, NET_SHAPER_A_LEAVES) || + GENL_REQ_ATTR_CHECK(info, NET_SHAPER_A_NODE)) + return -EINVAL; + + binding = net_shaper_binding_from_ctx(info->user_ptr[0]); + leaves_count = net_shaper_list_len(info, NET_SHAPER_A_LEAVES); + leaves = kcalloc(leaves_count, sizeof(struct net_shaper_info) + + sizeof(struct net_shaper_handle), GFP_KERNEL); + if (!leaves) { + GENL_SET_ERR_MSG_FMT(info, "Can't allocate memory for %d leaves shapers", + leaves_count); + return -ENOMEM; + } + leaves_handles = (struct net_shaper_handle *)&leaves[leaves_count]; + + ret = net_shaper_parse_node(binding, info->attrs[NET_SHAPER_A_NODE], + info, &node_handle, &node); + if (ret) + goto free_shapers; + + i = 0; + nla_for_each_attr_type(attr, NET_SHAPER_A_LEAVES, + genlmsg_data(info->genlhdr), + genlmsg_len(info->genlhdr), rem) { + if (WARN_ON_ONCE(i >= leaves_count)) + goto free_shapers; + + ret = net_shaper_parse_info_nest(binding, attr, info, + NET_SHAPER_SCOPE_QUEUE, + &leaves_handles[i], + &leaves[i]); + if (ret) + goto free_shapers; + i++; + } + + ret = net_shaper_group(binding, leaves_count, leaves_handles, leaves, + &node_handle, &node, info->extack); + if (ret < 0) + goto free_shapers; + + ret = net_shaper_group_send_reply(info, &node_handle); + if (ret) { + /* Error on reply is not fatal to avoid rollback a successful + * configuration. + */ + GENL_SET_ERR_MSG_FMT(info, "Can't send reply %d", ret); + ret = 0; + } + +free_shapers: + kfree(leaves); + return ret; +} + static void net_shaper_flush(struct net_shaper_binding *binding) { struct net_shaper_data *data = net_shaper_binding_data(binding); -- 2.45.2
