X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fnetdev.c;h=c70105ba06755cab4d3c9fd6ed5151059ba719e2;hb=fa04edcedfe5285fd8ad3a4d70fecb38df18293d;hp=25615380f4febd7cbc5e35ac6f60e0549d12e91e;hpb=2f980d741737fd3296d8063d800753a2d77bd730;p=sliver-openvswitch.git diff --git a/lib/netdev.c b/lib/netdev.c index 25615380f..c70105ba0 100644 --- a/lib/netdev.c +++ b/lib/netdev.c @@ -56,10 +56,31 @@ struct netdev_saved_flags { enum netdev_flags saved_values; }; -static struct shash netdev_classes = SHASH_INITIALIZER(&netdev_classes); +/* Protects 'netdev_shash' and the mutable members of struct netdev. */ +static struct ovs_mutex netdev_mutex = OVS_MUTEX_INITIALIZER; /* All created network devices. */ -static struct shash netdev_shash = SHASH_INITIALIZER(&netdev_shash); +static struct shash netdev_shash OVS_GUARDED_BY(netdev_mutex) + = SHASH_INITIALIZER(&netdev_shash); + +/* Protects 'netdev_classes' against insertions or deletions. + * + * This is not an rwlock for performance reasons but to allow recursive + * acquisition when calling into providers. For example, netdev_run() calls + * into provider 'run' functions, which might reasonably want to call one of + * the netdev functions that takes netdev_class_rwlock read-only. */ +static struct ovs_rwlock netdev_class_rwlock OVS_ACQ_BEFORE(netdev_mutex) + = OVS_RWLOCK_INITIALIZER; + +/* Contains 'struct netdev_registered_class'es. */ +static struct hmap netdev_classes OVS_GUARDED_BY(netdev_class_rwlock) + = HMAP_INITIALIZER(&netdev_classes); + +struct netdev_registered_class { + struct hmap_node hmap_node; /* In 'netdev_classes', by class->type. */ + const struct netdev_class *class; + atomic_int ref_cnt; /* Number of 'struct netdev's of this class. */ +}; /* This is set pretty low because we probably won't learn anything from the * additional log messages. */ @@ -70,12 +91,11 @@ void update_device_args(struct netdev *, const struct shash *args); static void netdev_initialize(void) + OVS_EXCLUDED(netdev_class_rwlock, netdev_mutex) { - static bool inited; - - if (!inited) { - inited = true; + static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER; + if (ovsthread_once_start(&once)) { fatal_signal_add_hook(restore_all_flags, NULL, NULL, true); netdev_vport_patch_register(); @@ -89,6 +109,10 @@ netdev_initialize(void) netdev_register_provider(&netdev_tap_class); netdev_register_provider(&netdev_bsd_class); #endif + netdev_register_provider(&netdev_tunnel_class); + netdev_register_provider(&netdev_pltap_class); + + ovsthread_once_done(&once); } } @@ -98,14 +122,15 @@ netdev_initialize(void) * main poll loop. */ void netdev_run(void) + OVS_EXCLUDED(netdev_class_rwlock, netdev_mutex) { - struct shash_node *node; - SHASH_FOR_EACH(node, &netdev_classes) { - const struct netdev_class *netdev_class = node->data; - if (netdev_class->run) { - netdev_class->run(); - } + struct netdev_registered_class *rc; + + ovs_rwlock_rdlock(&netdev_class_rwlock); + HMAP_FOR_EACH (rc, hmap_node, &netdev_classes) { + rc->class->run(); } + ovs_rwlock_unlock(&netdev_class_rwlock); } /* Arranges for poll_block() to wake up when netdev_run() needs to be called. @@ -114,39 +139,63 @@ netdev_run(void) * main poll loop. */ void netdev_wait(void) + OVS_EXCLUDED(netdev_class_rwlock, netdev_mutex) { - struct shash_node *node; - SHASH_FOR_EACH(node, &netdev_classes) { - const struct netdev_class *netdev_class = node->data; - if (netdev_class->wait) { - netdev_class->wait(); + struct netdev_registered_class *rc; + + ovs_rwlock_rdlock(&netdev_class_rwlock); + HMAP_FOR_EACH (rc, hmap_node, &netdev_classes) { + rc->class->wait(); + } + ovs_rwlock_unlock(&netdev_class_rwlock); +} + +static struct netdev_registered_class * +netdev_lookup_class(const char *type) + OVS_REQ_RDLOCK(netdev_class_rwlock) +{ + struct netdev_registered_class *rc; + + HMAP_FOR_EACH_WITH_HASH (rc, hmap_node, hash_string(type, 0), + &netdev_classes) { + if (!strcmp(type, rc->class->type)) { + return rc; } } + return NULL; } /* Initializes and registers a new netdev provider. After successful * registration, new netdevs of that type can be opened using netdev_open(). */ int netdev_register_provider(const struct netdev_class *new_class) + OVS_EXCLUDED(netdev_class_rwlock, netdev_mutex) { - if (shash_find(&netdev_classes, new_class->type)) { + int error; + + ovs_rwlock_wrlock(&netdev_class_rwlock); + if (netdev_lookup_class(new_class->type)) { VLOG_WARN("attempted to register duplicate netdev provider: %s", new_class->type); - return EEXIST; - } - - if (new_class->init) { - int error = new_class->init(); - if (error) { + error = EEXIST; + } else { + error = new_class->init ? new_class->init() : 0; + if (!error) { + struct netdev_registered_class *rc; + + rc = xmalloc(sizeof *rc); + hmap_insert(&netdev_classes, &rc->hmap_node, + hash_string(new_class->type, 0)); + rc->class = new_class; + atomic_init(&rc->ref_cnt, 0); + } else { VLOG_ERR("failed to initialize %s network device class: %s", new_class->type, ovs_strerror(error)); - return error; } } + ovs_rwlock_unlock(&netdev_class_rwlock); - shash_add(&netdev_classes, new_class->type, new_class); - - return 0; + return error; } /* Unregisters a netdev provider. 'type' must have been previously @@ -154,51 +203,52 @@ netdev_register_provider(const struct netdev_class *new_class) * new netdevs of that type cannot be opened using netdev_open(). */ int netdev_unregister_provider(const char *type) + OVS_EXCLUDED(netdev_class_rwlock, netdev_mutex) { - struct shash_node *del_node, *netdev_node; + struct netdev_registered_class *rc; + int error; - del_node = shash_find(&netdev_classes, type); - if (!del_node) { + ovs_rwlock_wrlock(&netdev_class_rwlock); + rc = netdev_lookup_class(type); + if (!rc) { VLOG_WARN("attempted to unregister a netdev provider that is not " "registered: %s", type); - return EAFNOSUPPORT; - } - - SHASH_FOR_EACH (netdev_node, &netdev_shash) { - struct netdev *netdev = netdev_node->data; - if (!strcmp(netdev->netdev_class->type, type)) { + error = EAFNOSUPPORT; + } else { + int ref_cnt; + + atomic_read(&rc->ref_cnt, &ref_cnt); + if (!ref_cnt) { + hmap_remove(&netdev_classes, &rc->hmap_node); + free(rc); + error = 0; + } else { VLOG_WARN("attempted to unregister in use netdev provider: %s", type); - return EBUSY; + error = EBUSY; } } + ovs_rwlock_unlock(&netdev_class_rwlock); - shash_delete(&netdev_classes, del_node); - - return 0; -} - -const struct netdev_class * -netdev_lookup_provider(const char *type) -{ - netdev_initialize(); - return shash_find_data(&netdev_classes, type && type[0] ? type : "system"); + return error; } /* Clears 'types' and enumerates the types of all currently registered netdev * providers into it. The caller must first initialize the sset. */ void netdev_enumerate_types(struct sset *types) + OVS_EXCLUDED(netdev_mutex) { - struct shash_node *node; + struct netdev_registered_class *rc; netdev_initialize(); sset_clear(types); - SHASH_FOR_EACH(node, &netdev_classes) { - const struct netdev_class *netdev_class = node->data; - sset_add(types, netdev_class->type); + ovs_rwlock_rdlock(&netdev_class_rwlock); + HMAP_FOR_EACH (rc, hmap_node, &netdev_classes) { + sset_add(types, rc->class->type); } + ovs_rwlock_unlock(&netdev_class_rwlock); } /* Check that the network device name is not the same as any of the registered @@ -208,17 +258,21 @@ netdev_enumerate_types(struct sset *types) * Returns true if there is a name conflict, false otherwise. */ bool netdev_is_reserved_name(const char *name) + OVS_EXCLUDED(netdev_mutex) { - struct shash_node *node; + struct netdev_registered_class *rc; netdev_initialize(); - SHASH_FOR_EACH (node, &netdev_classes) { - const char *dpif_port; - dpif_port = netdev_vport_class_get_dpif_port(node->data); + + ovs_rwlock_rdlock(&netdev_class_rwlock); + HMAP_FOR_EACH (rc, hmap_node, &netdev_classes) { + const char *dpif_port = netdev_vport_class_get_dpif_port(rc->class); if (dpif_port && !strcmp(dpif_port, name)) { + ovs_rwlock_unlock(&netdev_class_rwlock); return true; } } + ovs_rwlock_unlock(&netdev_class_rwlock); if (!strncmp(name, "ovs-", 4)) { struct sset types; @@ -247,46 +301,77 @@ netdev_is_reserved_name(const char *name) * before they can be used. */ int netdev_open(const char *name, const char *type, struct netdev **netdevp) + OVS_EXCLUDED(netdev_mutex) { struct netdev *netdev; int error; - *netdevp = NULL; netdev_initialize(); + ovs_rwlock_rdlock(&netdev_class_rwlock); + ovs_mutex_lock(&netdev_mutex); netdev = shash_find_data(&netdev_shash, name); if (!netdev) { - const struct netdev_class *class; - - class = netdev_lookup_provider(type); - if (!class) { + struct netdev_registered_class *rc; + + rc = netdev_lookup_class(type && type[0] ? type : "system"); + if (rc) { + netdev = rc->class->alloc(); + if (netdev) { + memset(netdev, 0, sizeof *netdev); + netdev->netdev_class = rc->class; + netdev->name = xstrdup(name); + netdev->node = shash_add(&netdev_shash, name, netdev); + list_init(&netdev->saved_flags_list); + + error = rc->class->construct(netdev); + if (!error) { + int old_ref_cnt; + + atomic_add(&rc->ref_cnt, 1, &old_ref_cnt); + } else { + free(netdev->name); + ovs_assert(list_is_empty(&netdev->saved_flags_list)); + shash_delete(&netdev_shash, netdev->node); + rc->class->dealloc(netdev); + } + } else { + error = ENOMEM; + } + } else { VLOG_WARN("could not create netdev %s of unknown type %s", name, type); - return EAFNOSUPPORT; - } - error = class->create(class, name, &netdev); - if (error) { - return error; + error = EAFNOSUPPORT; } - ovs_assert(netdev->netdev_class == class); - + } else { + error = 0; } - netdev->ref_cnt++; - *netdevp = netdev; - return 0; + ovs_mutex_unlock(&netdev_mutex); + ovs_rwlock_unlock(&netdev_class_rwlock); + + if (!error) { + netdev->ref_cnt++; + *netdevp = netdev; + } else { + *netdevp = NULL; + } + return error; } /* Returns a reference to 'netdev_' for the caller to own. Returns null if * 'netdev_' is null. */ struct netdev * netdev_ref(const struct netdev *netdev_) + OVS_EXCLUDED(netdev_mutex) { struct netdev *netdev = CONST_CAST(struct netdev *, netdev_); if (netdev) { + ovs_mutex_lock(&netdev_mutex); ovs_assert(netdev->ref_cnt > 0); netdev->ref_cnt++; + ovs_mutex_unlock(&netdev_mutex); } return netdev; } @@ -295,9 +380,10 @@ netdev_ref(const struct netdev *netdev_) * or NULL if none are needed. */ int netdev_set_config(struct netdev *netdev, const struct smap *args) + OVS_EXCLUDED(netdev_mutex) { if (netdev->netdev_class->set_config) { - struct smap no_args = SMAP_INITIALIZER(&no_args); + const struct smap no_args = SMAP_INITIALIZER(&no_args); return netdev->netdev_class->set_config(netdev, args ? args : &no_args); } else if (args && !smap_is_empty(args)) { @@ -317,6 +403,7 @@ netdev_set_config(struct netdev *netdev, const struct smap *args) * smap_destroy(). */ int netdev_get_config(const struct netdev *netdev, struct smap *args) + OVS_EXCLUDED(netdev_mutex) { int error; @@ -335,6 +422,7 @@ netdev_get_config(const struct netdev *netdev, struct smap *args) const struct netdev_tunnel_config * netdev_get_tunnel_config(const struct netdev *netdev) + OVS_EXCLUDED(netdev_mutex) { if (netdev->netdev_class->get_tunnel_config) { return netdev->netdev_class->get_tunnel_config(netdev); @@ -345,18 +433,38 @@ netdev_get_tunnel_config(const struct netdev *netdev) static void netdev_unref(struct netdev *dev) + OVS_RELEASES(netdev_mutex) { ovs_assert(dev->ref_cnt); if (!--dev->ref_cnt) { - netdev_uninit(dev, true); + const struct netdev_class *class = dev->netdev_class; + struct netdev_registered_class *rc; + int old_ref_cnt; + + dev->netdev_class->destruct(dev); + + shash_delete(&netdev_shash, dev->node); + free(dev->name); + dev->netdev_class->dealloc(dev); + ovs_mutex_unlock(&netdev_mutex); + + ovs_rwlock_rdlock(&netdev_class_rwlock); + rc = netdev_lookup_class(class->type); + atomic_sub(&rc->ref_cnt, 1, &old_ref_cnt); + ovs_assert(old_ref_cnt > 0); + ovs_rwlock_unlock(&netdev_class_rwlock); + } else { + ovs_mutex_unlock(&netdev_mutex); } } /* Closes and destroys 'netdev'. */ void netdev_close(struct netdev *netdev) + OVS_EXCLUDED(netdev_mutex) { if (netdev) { + ovs_mutex_lock(&netdev_mutex); netdev_unref(netdev); } } @@ -382,29 +490,44 @@ netdev_parse_name(const char *netdev_name_, char **name, char **type) int netdev_rx_open(struct netdev *netdev, struct netdev_rx **rxp) + OVS_EXCLUDED(netdev_mutex) { int error; - error = (netdev->netdev_class->rx_open - ? netdev->netdev_class->rx_open(netdev, rxp) - : EOPNOTSUPP); - if (!error) { - ovs_assert((*rxp)->netdev == netdev); - netdev->ref_cnt++; + if (netdev->netdev_class->rx_alloc) { + struct netdev_rx *rx = netdev->netdev_class->rx_alloc(); + if (rx) { + rx->netdev = netdev; + error = netdev->netdev_class->rx_construct(rx); + if (!error) { + ovs_mutex_lock(&netdev_mutex); + netdev->ref_cnt++; + ovs_mutex_unlock(&netdev_mutex); + + *rxp = rx; + return 0; + } + netdev->netdev_class->rx_dealloc(rx); + } else { + error = ENOMEM; + } } else { - *rxp = NULL; + error = EOPNOTSUPP; } + + *rxp = NULL; return error; } void netdev_rx_close(struct netdev_rx *rx) + OVS_EXCLUDED(netdev_mutex) { if (rx) { - struct netdev *dev = rx->netdev; - - rx->rx_class->destroy(rx); - netdev_unref(dev); + struct netdev *netdev = rx->netdev; + netdev->netdev_class->rx_destruct(rx); + netdev->netdev_class->rx_dealloc(rx); + netdev_close(netdev); } } @@ -416,7 +539,8 @@ netdev_rx_recv(struct netdev_rx *rx, struct ofpbuf *buffer) ovs_assert(buffer->size == 0); ovs_assert(ofpbuf_tailroom(buffer) >= ETH_TOTAL_MIN); - retval = rx->rx_class->recv(rx, buffer->data, ofpbuf_tailroom(buffer)); + retval = rx->netdev->netdev_class->rx_recv(rx, buffer->data, + ofpbuf_tailroom(buffer)); if (retval >= 0) { COVERAGE_INC(netdev_received); buffer->size += retval; @@ -432,13 +556,15 @@ netdev_rx_recv(struct netdev_rx *rx, struct ofpbuf *buffer) void netdev_rx_wait(struct netdev_rx *rx) { - rx->rx_class->wait(rx); + rx->netdev->netdev_class->rx_wait(rx); } int netdev_rx_drain(struct netdev_rx *rx) { - return rx->rx_class->drain ? rx->rx_class->drain(rx) : 0; + return (rx->netdev->netdev_class->rx_drain + ? rx->netdev->netdev_class->rx_drain(rx) + : 0); } /* Sends 'buffer' on 'netdev'. Returns 0 if successful, otherwise a positive @@ -815,6 +941,7 @@ static int do_update_flags(struct netdev *netdev, enum netdev_flags off, enum netdev_flags on, enum netdev_flags *old_flagsp, struct netdev_saved_flags **sfp) + OVS_EXCLUDED(netdev_mutex) { struct netdev_saved_flags *sf = NULL; enum netdev_flags old_flags; @@ -831,6 +958,7 @@ do_update_flags(struct netdev *netdev, enum netdev_flags off, enum netdev_flags new_flags = (old_flags & ~off) | on; enum netdev_flags changed_flags = old_flags ^ new_flags; if (changed_flags) { + ovs_mutex_lock(&netdev_mutex); *sfp = sf = xmalloc(sizeof *sf); sf->netdev = netdev; list_push_front(&netdev->saved_flags_list, &sf->node); @@ -838,6 +966,7 @@ do_update_flags(struct netdev *netdev, enum netdev_flags off, sf->saved_values = changed_flags & new_flags; netdev->ref_cnt++; + ovs_mutex_unlock(&netdev_mutex); } } @@ -901,6 +1030,7 @@ netdev_turn_flags_off(struct netdev *netdev, enum netdev_flags flags, * Does nothing if 'sf' is NULL. */ void netdev_restore_flags(struct netdev_saved_flags *sf) + OVS_EXCLUDED(netdev_mutex) { if (sf) { struct netdev *netdev = sf->netdev; @@ -910,9 +1040,10 @@ netdev_restore_flags(struct netdev_saved_flags *sf) sf->saved_flags & sf->saved_values, sf->saved_flags & ~sf->saved_values, &old_flags); + + ovs_mutex_lock(&netdev_mutex); list_remove(&sf->node); free(sf); - netdev_unref(netdev); } } @@ -1326,48 +1457,6 @@ netdev_change_seq(const struct netdev *netdev) return netdev->netdev_class->change_seq(netdev); } -/* Initializes 'netdev' as a netdev device named 'name' of the specified - * 'netdev_class'. This function is ordinarily called from a netdev provider's - * 'create' function. - * - * This function adds 'netdev' to a netdev-owned shash, so it is very important - * that 'netdev' only be freed after calling netdev_uninit(). */ -void -netdev_init(struct netdev *netdev, const char *name, - const struct netdev_class *netdev_class) -{ - ovs_assert(!shash_find(&netdev_shash, name)); - - memset(netdev, 0, sizeof *netdev); - netdev->netdev_class = netdev_class; - netdev->name = xstrdup(name); - netdev->node = shash_add(&netdev_shash, name, netdev); - list_init(&netdev->saved_flags_list); -} - -/* Undoes the results of initialization. - * - * Normally this function does not need to be called as netdev_close has - * the same effect when the refcount drops to zero. - * However, it may be called by providers due to an error on creation - * that occurs after initialization. It this case netdev_close() would - * never be called. */ -void -netdev_uninit(struct netdev *netdev, bool destroy) -{ - char *name = netdev->name; - - ovs_assert(!netdev->ref_cnt); - ovs_assert(list_is_empty(&netdev->saved_flags_list)); - - shash_delete(&netdev_shash, netdev->node); - - if (destroy) { - netdev->netdev_class->destroy(netdev); - } - free(name); -} - /* Returns the class type of 'netdev'. * * The caller must not free the returned value. */ @@ -1386,11 +1475,21 @@ netdev_get_class(const struct netdev *netdev) /* Returns the netdev with 'name' or NULL if there is none. * - * The caller must not free the returned value. */ + * The caller must free the returned netdev with netdev_close(). */ struct netdev * netdev_from_name(const char *name) + OVS_EXCLUDED(netdev_mutex) { - return shash_find_data(&netdev_shash, name); + struct netdev *netdev; + + ovs_mutex_lock(&netdev_mutex); + netdev = shash_find_data(&netdev_shash, name); + if (netdev) { + netdev->ref_cnt++; + } + ovs_mutex_unlock(&netdev_mutex); + + return netdev; } /* Fills 'device_list' with devices that match 'netdev_class'. @@ -1400,8 +1499,11 @@ netdev_from_name(const char *name) void netdev_get_devices(const struct netdev_class *netdev_class, struct shash *device_list) + OVS_EXCLUDED(netdev_mutex) { struct shash_node *node; + + ovs_mutex_lock(&netdev_mutex); SHASH_FOR_EACH (node, &netdev_shash) { struct netdev *dev = node->data; @@ -1410,30 +1512,18 @@ netdev_get_devices(const struct netdev_class *netdev_class, shash_add(device_list, node->name, node->data); } } + ovs_mutex_unlock(&netdev_mutex); } const char * netdev_get_type_from_name(const char *name) { - const struct netdev *dev = netdev_from_name(name); - return dev ? netdev_get_type(dev) : NULL; + struct netdev *dev = netdev_from_name(name); + const char *type = dev ? netdev_get_type(dev) : NULL; + netdev_close(dev); + return type; } -void -netdev_rx_init(struct netdev_rx *rx, struct netdev *netdev, - const struct netdev_rx_class *class) -{ - ovs_assert(netdev->ref_cnt > 0); - rx->rx_class = class; - rx->netdev = netdev; -} - -void -netdev_rx_uninit(struct netdev_rx *rx OVS_UNUSED) -{ - /* Nothing to do. */ -} - struct netdev * netdev_rx_get_netdev(const struct netdev_rx *rx) {