X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=datapath%2Fvport.c;h=8ef96f73e1fc6ea7e77cb1881d5617e0be93ab85;hb=d7436f763874179e086ff1f86bb2fe72596973a0;hp=1416ed0cbbbecea01ce0eddffc4b22f99d1ce6d1;hpb=a80a9fbd061fe9023cd669d6fe0a4faea7e31af3;p=sliver-openvswitch.git diff --git a/datapath/vport.c b/datapath/vport.c index 1416ed0cb..8ef96f73e 100644 --- a/datapath/vport.c +++ b/datapath/vport.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include #include @@ -38,55 +39,10 @@ static const struct vport_ops *base_vport_ops_list[] = { static const struct vport_ops **vport_ops_list; static int n_vport_types; +/* Protected by RCU read lock for reading, RTNL lock for writing. */ static struct hlist_head *dev_table; #define VPORT_HASH_BUCKETS 1024 -/* Both RTNL lock and vport_mutex need to be held when updating dev_table. - * - * If you use vport_locate and then perform some operations, you need to hold - * one of these locks if you don't want the vport to be deleted out from under - * you. - * - * If you get a reference to a vport through a datapath, it is protected - * by RCU and you need to hold rcu_read_lock instead when reading. - * - * If multiple locks are taken, the hierarchy is: - * 1. RTNL - * 2. DP - * 3. vport - */ -static DEFINE_MUTEX(vport_mutex); - -/** - * vport_lock - acquire vport lock - * - * Acquire global vport lock. See above comment about locking requirements - * and specific function definitions. May sleep. - */ -void vport_lock(void) -{ - mutex_lock(&vport_mutex); -} - -/** - * vport_unlock - release vport lock - * - * Release lock acquired with vport_lock. - */ -void vport_unlock(void) -{ - mutex_unlock(&vport_mutex); -} - -#define ASSERT_VPORT() \ -do { \ - if (unlikely(!mutex_is_locked(&vport_mutex))) { \ - pr_err("vport lock not held at %s (%d)\n", \ - __FILE__, __LINE__); \ - dump_stack(); \ - } \ -} while (0) - /** * vport_init - initialize vport subsystem * @@ -155,277 +111,6 @@ void vport_exit(void) kfree(dev_table); } -/** - * vport_user_mod - modify existing vport device (for userspace callers) - * - * @uport: New configuration for vport - * - * Modifies an existing device with the specified configuration (which is - * dependent on device type). This function is for userspace callers and - * assumes no locks are held. - */ -int vport_user_mod(const struct odp_port __user *uport) -{ - struct odp_port port; - struct vport *vport; - int err; - - if (copy_from_user(&port, uport, sizeof(port))) - return -EFAULT; - - port.devname[IFNAMSIZ - 1] = '\0'; - - rtnl_lock(); - - vport = vport_locate(port.devname); - if (!vport) { - err = -ENODEV; - goto out; - } - - vport_lock(); - err = vport_mod(vport, &port); - vport_unlock(); - -out: - rtnl_unlock(); - return err; -} - -/** - * vport_user_stats_get - retrieve device stats (for userspace callers) - * - * @ustats_req: Stats request parameters. - * - * Retrieves transmit, receive, and error stats for the given device. This - * function is for userspace callers and assumes no locks are held. - */ -int vport_user_stats_get(struct odp_vport_stats_req __user *ustats_req) -{ - struct odp_vport_stats_req stats_req; - struct vport *vport; - int err; - - if (copy_from_user(&stats_req, ustats_req, sizeof(struct odp_vport_stats_req))) - return -EFAULT; - - stats_req.devname[IFNAMSIZ - 1] = '\0'; - - vport_lock(); - - vport = vport_locate(stats_req.devname); - if (!vport) { - err = -ENODEV; - goto out; - } - - err = vport_get_stats(vport, &stats_req.stats); - -out: - vport_unlock(); - - if (!err) - if (copy_to_user(ustats_req, &stats_req, sizeof(struct odp_vport_stats_req))) - err = -EFAULT; - - return err; -} - -/** - * vport_user_stats_set - sets offset device stats (for userspace callers) - * - * @ustats_req: Stats set parameters. - * - * Provides a set of transmit, receive, and error stats to be added as an - * offset to the collect data when stats are retreived. Some devices may not - * support setting the stats, in which case the result will always be - * -EOPNOTSUPP. This function is for userspace callers and assumes no locks - * are held. - */ -int vport_user_stats_set(struct odp_vport_stats_req __user *ustats_req) -{ - struct odp_vport_stats_req stats_req; - struct vport *vport; - int err; - - if (copy_from_user(&stats_req, ustats_req, sizeof(struct odp_vport_stats_req))) - return -EFAULT; - - stats_req.devname[IFNAMSIZ - 1] = '\0'; - - rtnl_lock(); - vport_lock(); - - vport = vport_locate(stats_req.devname); - if (!vport) { - err = -ENODEV; - goto out; - } - - err = vport_set_stats(vport, &stats_req.stats); - -out: - vport_unlock(); - rtnl_unlock(); - return err; -} - - -/** - * vport_user_ether_get - retrieve device Ethernet address (for userspace callers) - * - * @uvport_ether: Ethernet address request parameters. - * - * Retrieves the Ethernet address of the given device. This function is for - * userspace callers and assumes no locks are held. - */ -int vport_user_ether_get(struct odp_vport_ether __user *uvport_ether) -{ - struct odp_vport_ether vport_ether; - struct vport *vport; - int err = 0; - - if (copy_from_user(&vport_ether, uvport_ether, sizeof(struct odp_vport_ether))) - return -EFAULT; - - vport_ether.devname[IFNAMSIZ - 1] = '\0'; - - vport_lock(); - - vport = vport_locate(vport_ether.devname); - if (!vport) { - err = -ENODEV; - goto out; - } - - rcu_read_lock(); - memcpy(vport_ether.ether_addr, vport_get_addr(vport), ETH_ALEN); - rcu_read_unlock(); - -out: - vport_unlock(); - - if (!err) - if (copy_to_user(uvport_ether, &vport_ether, sizeof(struct odp_vport_ether))) - err = -EFAULT; - - return err; -} - -/** - * vport_user_ether_set - set device Ethernet address (for userspace callers) - * - * @uvport_ether: Ethernet address request parameters. - * - * Sets the Ethernet address of the given device. Some devices may not support - * setting the Ethernet address, in which case the result will always be - * -EOPNOTSUPP. This function is for userspace callers and assumes no locks - * are held. - */ -int vport_user_ether_set(struct odp_vport_ether __user *uvport_ether) -{ - struct odp_vport_ether vport_ether; - struct vport *vport; - int err; - - if (copy_from_user(&vport_ether, uvport_ether, sizeof(struct odp_vport_ether))) - return -EFAULT; - - vport_ether.devname[IFNAMSIZ - 1] = '\0'; - - rtnl_lock(); - vport_lock(); - - vport = vport_locate(vport_ether.devname); - if (!vport) { - err = -ENODEV; - goto out; - } - - err = vport_set_addr(vport, vport_ether.ether_addr); - -out: - vport_unlock(); - rtnl_unlock(); - return err; -} - -/** - * vport_user_mtu_get - retrieve device MTU (for userspace callers) - * - * @uvport_mtu: MTU request parameters. - * - * Retrieves the MTU of the given device. This function is for userspace - * callers and assumes no locks are held. - */ -int vport_user_mtu_get(struct odp_vport_mtu __user *uvport_mtu) -{ - struct odp_vport_mtu vport_mtu; - struct vport *vport; - int err = 0; - - if (copy_from_user(&vport_mtu, uvport_mtu, sizeof(struct odp_vport_mtu))) - return -EFAULT; - - vport_mtu.devname[IFNAMSIZ - 1] = '\0'; - - vport_lock(); - - vport = vport_locate(vport_mtu.devname); - if (!vport) { - err = -ENODEV; - goto out; - } - - vport_mtu.mtu = vport_get_mtu(vport); - -out: - vport_unlock(); - - if (!err) - if (copy_to_user(uvport_mtu, &vport_mtu, sizeof(struct odp_vport_mtu))) - err = -EFAULT; - - return err; -} - -/** - * vport_user_mtu_set - set device MTU (for userspace callers) - * - * @uvport_mtu: MTU request parameters. - * - * Sets the MTU of the given device. Some devices may not support setting the - * MTU, in which case the result will always be -EOPNOTSUPP. This function is - * for userspace callers and assumes no locks are held. - */ -int vport_user_mtu_set(struct odp_vport_mtu __user *uvport_mtu) -{ - struct odp_vport_mtu vport_mtu; - struct vport *vport; - int err; - - if (copy_from_user(&vport_mtu, uvport_mtu, sizeof(struct odp_vport_mtu))) - return -EFAULT; - - vport_mtu.devname[IFNAMSIZ - 1] = '\0'; - - rtnl_lock(); - vport_lock(); - - vport = vport_locate(vport_mtu.devname); - if (!vport) { - err = -ENODEV; - goto out; - } - - err = vport_set_mtu(vport, vport_mtu.mtu); - -out: - vport_unlock(); - rtnl_unlock(); - return err; -} - static struct hlist_head *hash_bucket(const char *name) { unsigned int hash = full_name_hash(name, strlen(name)); @@ -437,9 +122,7 @@ static struct hlist_head *hash_bucket(const char *name) * * @name: name of port to find * - * Either RTNL or vport lock must be acquired before calling this function - * and held while using the found port. See the locking comments at the - * top of the file. + * Must be called with RTNL or RCU read lock. */ struct vport *vport_locate(const char *name) { @@ -447,32 +130,11 @@ struct vport *vport_locate(const char *name) struct vport *vport; struct hlist_node *node; - if (unlikely(!mutex_is_locked(&vport_mutex) && !rtnl_is_locked())) { - pr_err("neither RTNL nor vport lock held in vport_locate\n"); - dump_stack(); - } - - rcu_read_lock(); - - hlist_for_each_entry(vport, node, bucket, hash_node) + hlist_for_each_entry_rcu(vport, node, bucket, hash_node) if (!strcmp(name, vport_get_name(vport))) - goto out; - - vport = NULL; - -out: - rcu_read_unlock(); - return vport; -} - -static void register_vport(struct vport *vport) -{ - hlist_add_head(&vport->hash_node, hash_bucket(vport_get_name(vport))); -} + return vport; -static void unregister_vport(struct vport *vport) -{ - hlist_del(&vport->hash_node); + return NULL; } static void release_vport(struct kobject *kobj) @@ -541,6 +203,9 @@ struct vport *vport_alloc(int priv_size, const struct vport_ops *ops, const stru * @vport: vport to free * * Frees a vport allocated with vport_alloc() when it is no longer needed. + * + * The caller must ensure that an RCU grace period has passed since the last + * time @vport was in a datapath. */ void vport_free(struct vport *vport) { @@ -556,8 +221,7 @@ void vport_free(struct vport *vport) * @parms: Information about new vport. * * Creates a new vport with the specified configuration (which is dependent on - * device type) and attaches it to a datapath. Both RTNL and vport locks must - * be held. + * device type) and attaches it to a datapath. RTNL lock must be held. */ struct vport *vport_add(const struct vport_parms *parms) { @@ -566,17 +230,17 @@ struct vport *vport_add(const struct vport_parms *parms) int i; ASSERT_RTNL(); - ASSERT_VPORT(); for (i = 0; i < n_vport_types; i++) { - if (!strcmp(vport_ops_list[i]->type, parms->type)) { + if (vport_ops_list[i]->type == parms->type) { vport = vport_ops_list[i]->create(parms); if (IS_ERR(vport)) { err = PTR_ERR(vport); goto out; } - register_vport(vport); + hlist_add_head_rcu(&vport->hash_node, + hash_bucket(vport_get_name(vport))); return vport; } } @@ -588,39 +252,36 @@ out: } /** - * vport_mod - modify existing vport device (for kernel callers) + * vport_set_options - modify existing vport device (for kernel callers) * * @vport: vport to modify. * @port: New configuration. * * Modifies an existing device with the specified configuration (which is - * dependent on device type). Both RTNL and vport locks must be held. + * dependent on device type). RTNL lock must be held. */ -int vport_mod(struct vport *vport, struct odp_port *port) +int vport_set_options(struct vport *vport, struct nlattr *options) { ASSERT_RTNL(); - ASSERT_VPORT(); - if (vport->ops->modify) - return vport->ops->modify(vport, port); - else + if (!vport->ops->set_options) return -EOPNOTSUPP; + return vport->ops->set_options(vport, options); } /** - * vport_del - delete existing vport device (for kernel callers) + * vport_del - delete existing vport device * * @vport: vport to delete. * * Detaches @vport from its datapath and destroys it. It is possible to fail - * for reasons such as lack of memory. Both RTNL and vport locks must be held. + * for reasons such as lack of memory. RTNL lock must be held. */ int vport_del(struct vport *vport) { ASSERT_RTNL(); - ASSERT_VPORT(); - unregister_vport(vport); + hlist_del_rcu(&vport->hash_node); return vport->ops->destroy(vport); } @@ -679,7 +340,7 @@ int vport_set_addr(struct vport *vport, const unsigned char *addr) } /** - * vport_set_stats - sets offset device stats (for kernel callers) + * vport_set_stats - sets offset device stats * * @vport: vport on which to set stats * @stats: stats to set @@ -687,7 +348,9 @@ int vport_set_addr(struct vport *vport, const unsigned char *addr) * Provides a set of transmit, receive, and error stats to be added as an * offset to the collect data when stats are retreived. Some devices may not * support setting the stats, in which case the result will always be - * -EOPNOTSUPP. RTNL lock must be held. + * -EOPNOTSUPP. + * + * Must be called with RTNL lock. */ int vport_set_stats(struct vport *vport, struct rtnl_link_stats64 *stats) { @@ -699,9 +362,7 @@ int vport_set_stats(struct vport *vport, struct rtnl_link_stats64 *stats) spin_unlock_bh(&vport->stats_lock); return 0; - } else if (vport->ops->set_stats) - return vport->ops->set_stats(vport, stats); - else + } else return -EOPNOTSUPP; } @@ -723,10 +384,9 @@ const char *vport_get_name(const struct vport *vport) * * @vport: vport from which to retrieve the type. * - * Retrieves the type of the given device. Either RTNL lock or rcu_read_lock - * must be held for the entire duration that the type is in use. + * Retrieves the type of the given device. */ -const char *vport_get_type(const struct vport *vport) +enum odp_vport_type vport_get_type(const struct vport *vport) { return vport->ops->type; } @@ -773,12 +433,14 @@ static int vport_call_get_stats(struct vport *vport, struct rtnl_link_stats64 *s } /** - * vport_get_stats - retrieve device stats (for kernel callers) + * vport_get_stats - retrieve device stats * * @vport: vport from which to retrieve the stats * @stats: location to store stats * * Retrieves transmit, receive, and error stats for the given device. + * + * Must be called with RTNL lock or rcu_read_lock. */ int vport_get_stats(struct vport *vport, struct rtnl_link_stats64 *stats) { @@ -860,8 +522,9 @@ int vport_get_stats(struct vport *vport, struct rtnl_link_stats64 *stats) * * @vport: vport from which to retrieve the flags * - * Retrieves the flags of the given device. Either RTNL lock or rcu_read_lock - * must be held. + * Retrieves the flags of the given device. + * + * Must be called with RTNL lock or rcu_read_lock. */ unsigned vport_get_flags(const struct vport *vport) { @@ -873,8 +536,9 @@ unsigned vport_get_flags(const struct vport *vport) * * @vport: vport on which to check status. * - * Checks whether the given device is running. Either RTNL lock or - * rcu_read_lock must be held. + * Checks whether the given device is running. + * + * Must be called with RTNL lock or rcu_read_lock. */ int vport_is_running(const struct vport *vport) { @@ -886,8 +550,9 @@ int vport_is_running(const struct vport *vport) * * @vport: vport from which to check status * - * Retrieves the RFC2863 operstate of the given device. Either RTNL lock or - * rcu_read_lock must be held. + * Retrieves the RFC2863 operstate of the given device. + * + * Must be called with RTNL lock or rcu_read_lock. */ unsigned char vport_get_operstate(const struct vport *vport) { @@ -901,8 +566,9 @@ unsigned char vport_get_operstate(const struct vport *vport) * * Retrieves the system interface index of the given device or 0 if * the device does not have one (in the case of virtual ports). - * Returns a negative index on error. Either RTNL lock or - * rcu_read_lock must be held. + * Returns a negative index on error. + * + * Must be called with RTNL lock or rcu_read_lock. */ int vport_get_ifindex(const struct vport *vport) { @@ -920,8 +586,9 @@ int vport_get_ifindex(const struct vport *vport) * Retrieves the system link index of the given device. The link is the index * of the interface on which the packet will actually be sent. In most cases * this is the same as the ifindex but may be different for tunnel devices. - * Returns a negative index on error. Either RTNL lock or rcu_read_lock must - * be held. + * Returns a negative index on error. + * + * Must be called with RTNL lock or rcu_read_lock. */ int vport_get_iflink(const struct vport *vport) { @@ -934,32 +601,55 @@ int vport_get_iflink(const struct vport *vport) } /** - * vport_get_mtu - retrieve device MTU (for kernel callers) + * vport_get_mtu - retrieve device MTU * * @vport: vport from which to retrieve MTU * - * Retrieves the MTU of the given device. Either RTNL lock or rcu_read_lock - * must be held. + * Retrieves the MTU of the given device. Returns 0 if @vport does not have an + * MTU (as e.g. some tunnels do not). Either RTNL lock or rcu_read_lock must + * be held. */ int vport_get_mtu(const struct vport *vport) { + if (!vport->ops->get_mtu) + return 0; return vport->ops->get_mtu(vport); } /** - * vport_get_config - retrieve device configuration + * vport_get_options - retrieve device options * - * @vport: vport from which to retrieve the configuration. - * @config: buffer to store config, which must be at least the length - * of VPORT_CONFIG_SIZE. + * @vport: vport from which to retrieve the options. + * @skb: sk_buff where options should be appended. * - * Retrieves the configuration of the given device. Either RTNL lock or - * rcu_read_lock must be held. + * Retrieves the configuration of the given device, appending an + * %ODP_VPORT_ATTR_OPTIONS attribute that in turn contains nested + * vport-specific attributes to @skb. + * + * Returns 0 if successful, -EMSGSIZE if @skb has insufficient room, or another + * negative error code if a real error occurred. If an error occurs, @skb is + * left unmodified. + * + * Must be called with RTNL lock or rcu_read_lock. */ -void vport_get_config(const struct vport *vport, void *config) +int vport_get_options(const struct vport *vport, struct sk_buff *skb) { - if (vport->ops->get_config) - vport->ops->get_config(vport, config); + struct nlattr *nla; + + nla = nla_nest_start(skb, ODP_VPORT_ATTR_OPTIONS); + if (!nla) + return -EMSGSIZE; + + if (vport->ops->get_options) { + int err = vport->ops->get_options(vport, skb); + if (err) { + nla_nest_cancel(skb, nla); + return err; + } + } + + nla_nest_end(skb, nla); + return 0; } /** @@ -1022,7 +712,7 @@ int vport_send(struct vport *vport, struct sk_buff *skb) int sent; mtu = vport_get_mtu(vport); - if (unlikely(packet_length(skb) > mtu && !skb_is_gso(skb))) { + if (mtu && unlikely(packet_length(skb) > mtu && !skb_is_gso(skb))) { if (net_ratelimit()) pr_warn("%s: dropped over-mtu packet: %d > %d\n", dp_name(vport->dp), packet_length(skb), mtu);