/* * Copyright (c) 2009, 2010 Nicira Networks. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef XFIF_PROVIDER_H #define XFIF_PROVIDER_H 1 /* Provider interface to xfifs, which provide an interface to an Open vSwitch * datapath. A datapath is a collection of physical or virtual ports that are * exposed over OpenFlow as a single switch. Datapaths and the collections of * ports that they contain may be fixed or dynamic. */ #include #include "openflow/openflow.h" #include "xfif.h" #include "util.h" #ifdef __cplusplus extern "C" { #endif /* Open vSwitch datapath interface. * * This structure should be treated as opaque by xfif implementations. */ struct xfif { const struct xfif_class *xfif_class; char *base_name; char *full_name; uint8_t netflow_engine_type; uint8_t netflow_engine_id; }; void xfif_init(struct xfif *, const struct xfif_class *, const char *name, uint8_t netflow_engine_type, uint8_t netflow_engine_id); void xfif_uninit(struct xfif *xfif, bool close); static inline void xfif_assert_class(const struct xfif *xfif, const struct xfif_class *xfif_class) { assert(xfif->xfif_class == xfif_class); } /* Datapath interface class structure, to be defined by each implementation of * a datapath interface. * * These functions return 0 if successful or a positive errno value on failure, * except where otherwise noted. * * Most of these functions are expected to execute synchronously, that is, to * block as necessary to obtain a result. Thus, these functions may return * EAGAIN (or EWOULDBLOCK or EINPROGRESS) only where the function descriptions * explicitly say those errors are a possibility. We may relax this * requirement in the future if and when we encounter performance problems. */ struct xfif_class { /* Type of xfif in this class, e.g. "system", "netdev", etc. * * One of the providers should supply a "system" type, since this is * the type assumed if no type is specified when opening a xfif. */ const char *type; /* Performs periodic work needed by xfifs of this class, if any is * necessary. */ void (*run)(void); /* Arranges for poll_block() to wake up if the "run" member function needs * to be called. */ void (*wait)(void); /* Enumerates the names of all known created datapaths, if possible, into * 'all_dps'. The caller has already initialized 'all_dps' and other xfif * classes might already have added names to it. * * This is used by the vswitch at startup, so that it can delete any * datapaths that are not configured. * * Some kinds of datapaths might not be practically enumerable, in which * case this function may be a null pointer. */ int (*enumerate)(struct svec *all_dps); /* Attempts to open an existing xfif called 'name', if 'create' is false, * or to open an existing xfif or create a new one, if 'create' is true. * 'type' corresponds to the 'type' field used in the xfif_class * structure. * * If successful, stores a pointer to the new xfif in '*xfifp'. On failure * there are no requirements on what is stored in '*xfifp'. */ int (*open)(const char *name, const char *type, bool create, struct xfif **xfifp); /* Closes 'xfif' and frees associated memory. */ void (*close)(struct xfif *xfif); /* Enumerates all names that may be used to open 'xfif' into 'all_names'. * The Linux datapath, for example, supports opening a datapath both by * number, e.g. "dp0", and by the name of the datapath's local port. For * some datapaths, this might be an infinite set (e.g. in a file name, * slashes may be duplicated any number of times), in which case only the * names most likely to be used should be enumerated. * * The caller has already initialized 'all_names' and might already have * added some names to it. This function should not disturb any existing * names in 'all_names'. * * If a datapath class does not support multiple names for a datapath, this * function may be a null pointer. * * This is used by the vswitch at startup, */ int (*get_all_names)(const struct xfif *xfif, struct svec *all_names); /* Attempts to destroy the xfif underlying 'xfif'. * * If successful, 'xfif' will not be used again except as an argument for * the 'close' member function. */ int (*destroy)(struct xfif *xfif); /* Retrieves statistics for 'xfif' into 'stats'. */ int (*get_stats)(const struct xfif *xfif, struct xflow_stats *stats); /* Retrieves 'xfif''s current treatment of IP fragments into '*drop_frags': * true indicates that fragments are dropped, false indicates that * fragments are treated in the same way as other IP packets (except that * the L4 header cannot be read). */ int (*get_drop_frags)(const struct xfif *xfif, bool *drop_frags); /* Changes 'xfif''s treatment of IP fragments to 'drop_frags', whose * meaning is the same as for the get_drop_frags member function. */ int (*set_drop_frags)(struct xfif *xfif, bool drop_frags); /* Creates a new port in 'xfif' connected to network device 'devname'. * 'flags' is a set of XFLOW_PORT_* flags. If successful, sets '*port_no' * to the new port's port number. */ int (*port_add)(struct xfif *xfif, const char *devname, uint16_t flags, uint16_t *port_no); /* Removes port numbered 'port_no' from 'xfif'. */ int (*port_del)(struct xfif *xfif, uint16_t port_no); /* Queries 'xfif' for a port with the given 'port_no' or 'devname'. Stores * information about the port into '*port' if successful. */ int (*port_query_by_number)(const struct xfif *xfif, uint16_t port_no, struct xflow_port *port); int (*port_query_by_name)(const struct xfif *xfif, const char *devname, struct xflow_port *port); /* Stores in 'ports' information about up to 'n' ports attached to 'xfif', * in no particular order. Returns the number of ports attached to 'xfif' * (not the number stored), if successful, otherwise a negative errno * value. */ int (*port_list)(const struct xfif *xfif, struct xflow_port *ports, int n); /* Polls for changes in the set of ports in 'xfif'. If the set of ports in * 'xfif' has changed, then this function should do one of the * following: * * - Preferably: store the name of the device that was added to or deleted * from 'xfif' in '*devnamep' and return 0. The caller is responsible * for freeing '*devnamep' (with free()) when it no longer needs it. * * - Alternatively: return ENOBUFS, without indicating the device that was * added or deleted. * * Occasional 'false positives', in which the function returns 0 while * indicating a device that was not actually added or deleted or returns * ENOBUFS without any change, are acceptable. * * If the set of ports in 'xfif' has not changed, returns EAGAIN. May also * return other positive errno values to indicate that something has gone * wrong. */ int (*port_poll)(const struct xfif *xfif, char **devnamep); /* Arranges for the poll loop to wake up when 'port_poll' will return a * value other than EAGAIN. */ void (*port_poll_wait)(const struct xfif *xfif); /* Stores in 'ports' the port numbers of up to 'n' ports that belong to * 'group' in 'xfif'. Returns the number of ports in 'group' (not the * number stored), if successful, otherwise a negative errno value. */ int (*port_group_get)(const struct xfif *xfif, int group, uint16_t ports[], int n); /* Changes port group 'group' in 'xfif' to consist of the 'n' ports whose * numbers are given in 'ports'. * * Use the get_stats member function to obtain the number of supported port * groups. */ int (*port_group_set)(struct xfif *xfif, int group, const uint16_t ports[], int n); /* For each flow 'flow' in the 'n' flows in 'flows': * * - If a flow matching 'flow->key' exists in 'xfif': * * Stores 0 into 'flow->stats.error' and stores statistics for the flow * into 'flow->stats'. * * If 'flow->n_actions' is zero, then 'flow->actions' is ignored. If * 'flow->n_actions' is nonzero, then 'flow->actions' should point to * an array of the specified number of actions. At most that many of * the flow's actions will be copied into that array. * 'flow->n_actions' will be updated to the number of actions actually * present in the flow, which may be greater than the number stored if * the flow has more actions than space available in the array. * * - Flow-specific errors are indicated by a positive errno value in * 'flow->stats.error'. In particular, ENOENT indicates that no flow * matching 'flow->key' exists in 'xfif'. When an error value is stored, * the contents of 'flow->key' are preserved but other members of 'flow' * should be treated as indeterminate. * * Returns 0 if all 'n' flows in 'flows' were updated (whether they were * individually successful or not is indicated by 'flow->stats.error', * however). Returns a positive errno value if an error that prevented * this update occurred, in which the caller must not depend on any * elements in 'flows' being updated or not updated. */ int (*flow_get)(const struct xfif *xfif, struct xflow_flow flows[], int n); /* Adds or modifies a flow in 'xfif' as specified in 'put': * * - If the flow specified in 'put->flow' does not exist in 'xfif', then * behavior depends on whether XFLOWPF_CREATE is specified in 'put->flags': * if it is, the flow will be added, otherwise the operation will fail * with ENOENT. * * - Otherwise, the flow specified in 'put->flow' does exist in 'xfif'. * Behavior in this case depends on whether XFLOWPF_MODIFY is specified in * 'put->flags': if it is, the flow's actions will be updated, otherwise * the operation will fail with EEXIST. If the flow's actions are * updated, then its statistics will be zeroed if XFLOWPF_ZERO_STATS is set * in 'put->flags', left as-is otherwise. */ int (*flow_put)(struct xfif *xfif, struct xflow_flow_put *put); /* Deletes a flow matching 'flow->key' from 'xfif' or returns ENOENT if * 'xfif' does not contain such a flow. * * If successful, updates 'flow->stats', 'flow->n_actions', and * 'flow->actions' as described in more detail under the flow_get member * function below. */ int (*flow_del)(struct xfif *xfif, struct xflow_flow *flow); /* Deletes all flows from 'xfif' and clears all of its queues of received * packets. */ int (*flow_flush)(struct xfif *xfif); /* Stores up to 'n' flows in 'xfif' into 'flows', updating their statistics * and actions as described under the flow_get member function. If * successful, returns the number of flows actually present in 'xfif', * which might be greater than the number stored (if 'xfif' has more than * 'n' flows). On failure, returns a negative errno value. */ int (*flow_list)(const struct xfif *xfif, struct xflow_flow flows[], int n); /* Performs the 'n_actions' actions in 'actions' on the Ethernet frame * specified in 'packet'. * * Pretends that the frame was originally received on the port numbered * 'in_port'. This affects only XFLOWAT_OUTPUT_GROUP actions, which will * not send a packet out their input port. Specify the number of an unused * port (e.g. UINT16_MAX is currently always unused) to avoid this * behavior. */ int (*execute)(struct xfif *xfif, uint16_t in_port, const union xflow_action actions[], int n_actions, const struct ofpbuf *packet); /* Retrieves 'xfif''s "listen mask" into '*listen_mask'. Each XFLOWL_* bit * set in '*listen_mask' indicates the 'xfif' will receive messages of the * corresponding type when it calls the recv member function. */ int (*recv_get_mask)(const struct xfif *xfif, int *listen_mask); /* Sets 'xfif''s "listen mask" to 'listen_mask'. Each XFLOWL_* bit set in * 'listen_mask' indicates the 'xfif' will receive messages of the * corresponding type when it calls the recv member function. */ int (*recv_set_mask)(struct xfif *xfif, int listen_mask); /* Retrieves 'xfif''s sFlow sampling probability into '*probability'. * Return value is 0 or a positive errno value. EOPNOTSUPP indicates that * the datapath does not support sFlow, as does a null pointer. * * '*probability' is expressed as the number of packets out of UINT_MAX to * sample, e.g. probability/UINT_MAX is the probability of sampling a given * packet. */ int (*get_sflow_probability)(const struct xfif *xfif, uint32_t *probability); /* Sets 'xfif''s sFlow sampling probability to 'probability'. Return value * is 0 or a positive errno value. EOPNOTSUPP indicates that the datapath * does not support sFlow, as does a null pointer. * * 'probability' is expressed as the number of packets out of UINT_MAX to * sample, e.g. probability/UINT_MAX is the probability of sampling a given * packet. */ int (*set_sflow_probability)(struct xfif *xfif, uint32_t probability); /* Translates OpenFlow queue ID 'queue_id' (in host byte order) into a * priority value for use in the XFLOWAT_SET_PRIORITY action in * '*priority'. */ int (*queue_to_priority)(const struct xfif *xfif, uint32_t queue_id, uint32_t *priority); /* Attempts to receive a message from 'xfif'. If successful, stores the * message into '*packetp'. The message, if one is received, must begin * with 'struct xflow_msg' as a header, and must have at least * XFIF_RECV_MSG_PADDING bytes of headroom (allocated using * e.g. ofpbuf_reserve()). Only messages of the types selected with the * set_listen_mask member function should be received. * * This function must not block. If no message is ready to be received * when it is called, it should return EAGAIN without blocking. */ int (*recv)(struct xfif *xfif, struct ofpbuf **packetp); /* Arranges for the poll loop to wake up when 'xfif' has a message queued * to be received with the recv member function. */ void (*recv_wait)(struct xfif *xfif); }; extern const struct xfif_class xfif_linux_class; extern const struct xfif_class xfif_netdev_class; #ifdef __cplusplus } #endif #endif /* xfif-provider.h */