diff options
Diffstat (limited to 'net/ethtool/netlink.h')
| -rw-r--r-- | net/ethtool/netlink.h | 116 |
1 files changed, 115 insertions, 1 deletions
diff --git a/net/ethtool/netlink.h b/net/ethtool/netlink.h index 05d7183da894..6ec0dd06277f 100644 --- a/net/ethtool/netlink.h +++ b/net/ethtool/netlink.h @@ -200,16 +200,130 @@ static inline unsigned int ethnl_reply_header_size(void) nla_total_size(IFNAMSIZ)); } +/* GET request handling */ + +/* Unified processing of GET requests uses two data structures: request info + * and reply data. Request info holds information parsed from client request + * and its stays constant through all request processing. Reply data holds data + * retrieved from ethtool_ops callbacks or other internal sources which is used + * to compose the reply. When processing a dump request, request info is filled + * only once (when the request message is parsed) but reply data is filled for + * each reply message. + * + * Both structures consist of part common for all request types (struct + * ethnl_req_info and struct ethnl_reply_data defined below) and optional + * parts specific for each request type. Common part always starts at offset 0. + */ + /** * struct ethnl_req_info - base type of request information for GET requests * @dev: network device the request is for (may be null) * @flags: request flags common for all request types * - * This is a common base, additional members may follow after this structure. + * This is a common base for request specific structures holding data from + * parsed userspace request. These always embed struct ethnl_req_info at + * zero offset. */ struct ethnl_req_info { struct net_device *dev; u32 flags; }; +/** + * struct ethnl_reply_data - base type of reply data for GET requests + * @dev: device for current reply message; in single shot requests it is + * equal to ðnl_req_info.dev; in dumps it's different for each + * reply message + * + * This is a common base for request specific structures holding data for + * kernel reply message. These always embed struct ethnl_reply_data at zero + * offset. + */ +struct ethnl_reply_data { + struct net_device *dev; +}; + +static inline int ethnl_ops_begin(struct net_device *dev) +{ + if (dev && dev->ethtool_ops->begin) + return dev->ethtool_ops->begin(dev); + else + return 0; +} + +static inline void ethnl_ops_complete(struct net_device *dev) +{ + if (dev && dev->ethtool_ops->complete) + dev->ethtool_ops->complete(dev); +} + +/** + * struct ethnl_request_ops - unified handling of GET requests + * @request_cmd: command id for request (GET) + * @reply_cmd: command id for reply (GET_REPLY) + * @hdr_attr: attribute type for request header + * @max_attr: maximum (top level) attribute type + * @req_info_size: size of request info + * @reply_data_size: size of reply data + * @request_policy: netlink policy for message contents + * @allow_nodev_do: allow non-dump request with no device identification + * @parse_request: + * Parse request except common header (struct ethnl_req_info). Common + * header is already filled on entry, the rest up to @repdata_offset + * is zero initialized. This callback should only modify type specific + * request info by parsed attributes from request message. + * @prepare_data: + * Retrieve and prepare data needed to compose a reply message. Calls to + * ethtool_ops handlers are limited to this callback. Common reply data + * (struct ethnl_reply_data) is filled on entry, type specific part after + * it is zero initialized. This callback should only modify the type + * specific part of reply data. Device identification from struct + * ethnl_reply_data is to be used as for dump requests, it iterates + * through network devices while dev member of struct ethnl_req_info + * points to the device from client request. + * @reply_size: + * Estimate reply message size. Returned value must be sufficient for + * message payload without common reply header. The callback may returned + * estimate higher than actual message size if exact calculation would + * not be worth the saved memory space. + * @fill_reply: + * Fill reply message payload (except for common header) from reply data. + * The callback must not generate more payload than previously called + * ->reply_size() estimated. + * @cleanup_data: + * Optional cleanup called when reply data is no longer needed. Can be + * used e.g. to free any additional data structures outside the main + * structure which were allocated by ->prepare_data(). When processing + * dump requests, ->cleanup() is called for each message. + * + * Description of variable parts of GET request handling when using the + * unified infrastructure. When used, a pointer to an instance of this + * structure is to be added to ðnl_default_requests array and generic + * handlers ethnl_default_doit(), ethnl_default_dumpit(), + * ethnl_default_start() and ethnl_default_done() used in @ethtool_genl_ops. + */ +struct ethnl_request_ops { + u8 request_cmd; + u8 reply_cmd; + u16 hdr_attr; + unsigned int max_attr; + unsigned int req_info_size; + unsigned int reply_data_size; + const struct nla_policy *request_policy; + bool allow_nodev_do; + + int (*parse_request)(struct ethnl_req_info *req_info, + struct nlattr **tb, + struct netlink_ext_ack *extack); + int (*prepare_data)(const struct ethnl_req_info *req_info, + struct ethnl_reply_data *reply_data, + struct genl_info *info); + int (*reply_size)(const struct ethnl_req_info *req_info, + const struct ethnl_reply_data *reply_data); + int (*fill_reply)(struct sk_buff *skb, + const struct ethnl_req_info *req_info, + const struct ethnl_reply_data *reply_data); + void (*cleanup_data)(struct ethnl_reply_data *reply_data); +}; + #endif /* _NET_ETHTOOL_NETLINK_H */ |