diff options
Diffstat (limited to 'net/ipv4/udp_tunnel_nic.c')
| -rw-r--r-- | net/ipv4/udp_tunnel_nic.c | 973 |
1 files changed, 973 insertions, 0 deletions
diff --git a/net/ipv4/udp_tunnel_nic.c b/net/ipv4/udp_tunnel_nic.c new file mode 100644 index 000000000000..bc3a043a5d5c --- /dev/null +++ b/net/ipv4/udp_tunnel_nic.c @@ -0,0 +1,973 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (c) 2020 Facebook Inc. + +#include <linux/ethtool_netlink.h> +#include <linux/netdevice.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/workqueue.h> +#include <net/udp_tunnel.h> +#include <net/vxlan.h> + +enum udp_tunnel_nic_table_entry_flags { + UDP_TUNNEL_NIC_ENTRY_ADD = BIT(0), + UDP_TUNNEL_NIC_ENTRY_DEL = BIT(1), + UDP_TUNNEL_NIC_ENTRY_OP_FAIL = BIT(2), + UDP_TUNNEL_NIC_ENTRY_FROZEN = BIT(3), +}; + +struct udp_tunnel_nic_table_entry { + __be16 port; + u8 type; + u8 flags; + u16 use_cnt; +#define UDP_TUNNEL_NIC_USE_CNT_MAX U16_MAX + u8 hw_priv; +}; + +/** + * struct udp_tunnel_nic - UDP tunnel port offload state + * @work: async work for talking to hardware from process context + * @dev: netdev pointer + * @need_sync: at least one port start changed + * @need_replay: space was freed, we need a replay of all ports + * @work_pending: @work is currently scheduled + * @n_tables: number of tables under @entries + * @missed: bitmap of tables which overflown + * @entries: table of tables of ports currently offloaded + */ +struct udp_tunnel_nic { + struct work_struct work; + + struct net_device *dev; + + u8 need_sync:1; + u8 need_replay:1; + u8 work_pending:1; + + unsigned int n_tables; + unsigned long missed; + struct udp_tunnel_nic_table_entry **entries; +}; + +/* We ensure all work structs are done using driver state, but not the code. + * We need a workqueue we can flush before module gets removed. + */ +static struct workqueue_struct *udp_tunnel_nic_workqueue; + +static const char *udp_tunnel_nic_tunnel_type_name(unsigned int type) +{ + switch (type) { + case UDP_TUNNEL_TYPE_VXLAN: + return "vxlan"; + case UDP_TUNNEL_TYPE_GENEVE: + return "geneve"; + case UDP_TUNNEL_TYPE_VXLAN_GPE: + return "vxlan-gpe"; + default: + return "unknown"; + } +} + +static bool +udp_tunnel_nic_entry_is_free(struct udp_tunnel_nic_table_entry *entry) +{ + return entry->use_cnt == 0 && !entry->flags; +} + +static bool +udp_tunnel_nic_entry_is_present(struct udp_tunnel_nic_table_entry *entry) +{ + return entry->use_cnt && !(entry->flags & ~UDP_TUNNEL_NIC_ENTRY_FROZEN); +} + +static bool +udp_tunnel_nic_entry_is_frozen(struct udp_tunnel_nic_table_entry *entry) +{ + return entry->flags & UDP_TUNNEL_NIC_ENTRY_FROZEN; +} + +static void +udp_tunnel_nic_entry_freeze_used(struct udp_tunnel_nic_table_entry *entry) +{ + if (!udp_tunnel_nic_entry_is_free(entry)) + entry->flags |= UDP_TUNNEL_NIC_ENTRY_FROZEN; +} + +static void +udp_tunnel_nic_entry_unfreeze(struct udp_tunnel_nic_table_entry *entry) +{ + entry->flags &= ~UDP_TUNNEL_NIC_ENTRY_FROZEN; +} + +static bool +udp_tunnel_nic_entry_is_queued(struct udp_tunnel_nic_table_entry *entry) +{ + return entry->flags & (UDP_TUNNEL_NIC_ENTRY_ADD | + UDP_TUNNEL_NIC_ENTRY_DEL); +} + +static void +udp_tunnel_nic_entry_queue(struct udp_tunnel_nic *utn, + struct udp_tunnel_nic_table_entry *entry, + unsigned int flag) +{ + entry->flags |= flag; + utn->need_sync = 1; +} + +static void +udp_tunnel_nic_ti_from_entry(struct udp_tunnel_nic_table_entry *entry, + struct udp_tunnel_info *ti) +{ + memset(ti, 0, sizeof(*ti)); + ti->port = entry->port; + ti->type = entry->type; + ti->hw_priv = entry->hw_priv; +} + +static bool +udp_tunnel_nic_is_empty(struct net_device *dev, struct udp_tunnel_nic *utn) +{ + const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; + unsigned int i, j; + + for (i = 0; i < utn->n_tables; i++) + for (j = 0; j < info->tables[i].n_entries; j++) + if (!udp_tunnel_nic_entry_is_free(&utn->entries[i][j])) + return false; + return true; +} + +static bool +udp_tunnel_nic_should_replay(struct net_device *dev, struct udp_tunnel_nic *utn) +{ + const struct udp_tunnel_nic_table_info *table; + unsigned int i, j; + + if (!utn->missed) + return false; + + for (i = 0; i < utn->n_tables; i++) { + table = &dev->udp_tunnel_nic_info->tables[i]; + if (!test_bit(i, &utn->missed)) + continue; + + for (j = 0; j < table->n_entries; j++) + if (udp_tunnel_nic_entry_is_free(&utn->entries[i][j])) + return true; + } + + return false; +} + +static void +__udp_tunnel_nic_get_port(struct net_device *dev, unsigned int table, + unsigned int idx, struct udp_tunnel_info *ti) +{ + struct udp_tunnel_nic_table_entry *entry; + struct udp_tunnel_nic *utn; + + utn = dev->udp_tunnel_nic; + entry = &utn->entries[table][idx]; + + if (entry->use_cnt) + udp_tunnel_nic_ti_from_entry(entry, ti); +} + +static void +__udp_tunnel_nic_set_port_priv(struct net_device *dev, unsigned int table, + unsigned int idx, u8 priv) +{ + dev->udp_tunnel_nic->entries[table][idx].hw_priv = priv; +} + +static void +udp_tunnel_nic_entry_update_done(struct udp_tunnel_nic_table_entry *entry, + int err) +{ + bool dodgy = entry->flags & UDP_TUNNEL_NIC_ENTRY_OP_FAIL; + + WARN_ON_ONCE(entry->flags & UDP_TUNNEL_NIC_ENTRY_ADD && + entry->flags & UDP_TUNNEL_NIC_ENTRY_DEL); + + if (entry->flags & UDP_TUNNEL_NIC_ENTRY_ADD && + (!err || (err == -EEXIST && dodgy))) + entry->flags &= ~UDP_TUNNEL_NIC_ENTRY_ADD; + + if (entry->flags & UDP_TUNNEL_NIC_ENTRY_DEL && + (!err || (err == -ENOENT && dodgy))) + entry->flags &= ~UDP_TUNNEL_NIC_ENTRY_DEL; + + if (!err) + entry->flags &= ~UDP_TUNNEL_NIC_ENTRY_OP_FAIL; + else + entry->flags |= UDP_TUNNEL_NIC_ENTRY_OP_FAIL; +} + +static void +udp_tunnel_nic_device_sync_one(struct net_device *dev, + struct udp_tunnel_nic *utn, + unsigned int table, unsigned int idx) +{ + struct udp_tunnel_nic_table_entry *entry; + struct udp_tunnel_info ti; + int err; + + entry = &utn->entries[table][idx]; + if (!udp_tunnel_nic_entry_is_queued(entry)) + return; + + udp_tunnel_nic_ti_from_entry(entry, &ti); + if (entry->flags & UDP_TUNNEL_NIC_ENTRY_ADD) + err = dev->udp_tunnel_nic_info->set_port(dev, table, idx, &ti); + else + err = dev->udp_tunnel_nic_info->unset_port(dev, table, idx, + &ti); + udp_tunnel_nic_entry_update_done(entry, err); + + if (err) + netdev_warn(dev, + "UDP tunnel port sync failed port %d type %s: %d\n", + be16_to_cpu(entry->port), + udp_tunnel_nic_tunnel_type_name(entry->type), + err); +} + +static void +udp_tunnel_nic_device_sync_by_port(struct net_device *dev, + struct udp_tunnel_nic *utn) +{ + const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; + unsigned int i, j; + + for (i = 0; i < utn->n_tables; i++) + for (j = 0; j < info->tables[i].n_entries; j++) + udp_tunnel_nic_device_sync_one(dev, utn, i, j); +} + +static void +udp_tunnel_nic_device_sync_by_table(struct net_device *dev, + struct udp_tunnel_nic *utn) +{ + const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; + unsigned int i, j; + int err; + + for (i = 0; i < utn->n_tables; i++) { + /* Find something that needs sync in this table */ + for (j = 0; j < info->tables[i].n_entries; j++) + if (udp_tunnel_nic_entry_is_queued(&utn->entries[i][j])) + break; + if (j == info->tables[i].n_entries) + continue; + + err = info->sync_table(dev, i); + if (err) + netdev_warn(dev, "UDP tunnel port sync failed for table %d: %d\n", + i, err); + + for (j = 0; j < info->tables[i].n_entries; j++) { + struct udp_tunnel_nic_table_entry *entry; + + entry = &utn->entries[i][j]; + if (udp_tunnel_nic_entry_is_queued(entry)) + udp_tunnel_nic_entry_update_done(entry, err); + } + } +} + +static void +__udp_tunnel_nic_device_sync(struct net_device *dev, struct udp_tunnel_nic *utn) +{ + if (!utn->need_sync) + return; + + if (dev->udp_tunnel_nic_info->sync_table) + udp_tunnel_nic_device_sync_by_table(dev, utn); + else + udp_tunnel_nic_device_sync_by_port(dev, utn); + + utn->need_sync = 0; + /* Can't replay directly here, in case we come from the tunnel driver's + * notification - trying to replay may deadlock inside tunnel driver. + */ + utn->need_replay = udp_tunnel_nic_should_replay(dev, utn); +} + +static void +udp_tunnel_nic_device_sync(struct net_device *dev, struct udp_tunnel_nic *utn) +{ + const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; + bool may_sleep; + + if (!utn->need_sync) + return; + + /* Drivers which sleep in the callback need to update from + * the workqueue, if we come from the tunnel driver's notification. + */ + may_sleep = info->flags & UDP_TUNNEL_NIC_INFO_MAY_SLEEP; + if (!may_sleep) + __udp_tunnel_nic_device_sync(dev, utn); + if (may_sleep || utn->need_replay) { + queue_work(udp_tunnel_nic_workqueue, &utn->work); + utn->work_pending = 1; + } +} + +static bool +udp_tunnel_nic_table_is_capable(const struct udp_tunnel_nic_table_info *table, + struct udp_tunnel_info *ti) +{ + return table->tunnel_types & ti->type; +} + +static bool +udp_tunnel_nic_is_capable(struct net_device *dev, struct udp_tunnel_nic *utn, + struct udp_tunnel_info *ti) +{ + const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; + unsigned int i; + + /* Special case IPv4-only NICs */ + if (info->flags & UDP_TUNNEL_NIC_INFO_IPV4_ONLY && + ti->sa_family != AF_INET) + return false; + + for (i = 0; i < utn->n_tables; i++) + if (udp_tunnel_nic_table_is_capable(&info->tables[i], ti)) + return true; + return false; +} + +static int +udp_tunnel_nic_has_collision(struct net_device *dev, struct udp_tunnel_nic *utn, + struct udp_tunnel_info *ti) +{ + const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; + struct udp_tunnel_nic_table_entry *entry; + unsigned int i, j; + + for (i = 0; i < utn->n_tables; i++) + for (j = 0; j < info->tables[i].n_entries; j++) { + entry = &utn->entries[i][j]; + + if (!udp_tunnel_nic_entry_is_free(entry) && + entry->port == ti->port && + entry->type != ti->type) { + __set_bit(i, &utn->missed); + return true; + } + } + return false; +} + +static void +udp_tunnel_nic_entry_adj(struct udp_tunnel_nic *utn, + unsigned int table, unsigned int idx, int use_cnt_adj) +{ + struct udp_tunnel_nic_table_entry *entry = &utn->entries[table][idx]; + bool dodgy = entry->flags & UDP_TUNNEL_NIC_ENTRY_OP_FAIL; + unsigned int from, to; + + WARN_ON(entry->use_cnt + (u32)use_cnt_adj > U16_MAX); + + /* If not going from used to unused or vice versa - all done. + * For dodgy entries make sure we try to sync again (queue the entry). + */ + entry->use_cnt += use_cnt_adj; + if (!dodgy && !entry->use_cnt == !(entry->use_cnt - use_cnt_adj)) + return; + + /* Cancel the op before it was sent to the device, if possible, + * otherwise we'd need to take special care to issue commands + * in the same order the ports arrived. + */ + if (use_cnt_adj < 0) { + from = UDP_TUNNEL_NIC_ENTRY_ADD; + to = UDP_TUNNEL_NIC_ENTRY_DEL; + } else { + from = UDP_TUNNEL_NIC_ENTRY_DEL; + to = UDP_TUNNEL_NIC_ENTRY_ADD; + } + + if (entry->flags & from) { + entry->flags &= ~from; + if (!dodgy) + return; + } + + udp_tunnel_nic_entry_queue(utn, entry, to); +} + +static bool +udp_tunnel_nic_entry_try_adj(struct udp_tunnel_nic *utn, + unsigned int table, unsigned int idx, + struct udp_tunnel_info *ti, int use_cnt_adj) +{ + struct udp_tunnel_nic_table_entry *entry = &utn->entries[table][idx]; + + if (udp_tunnel_nic_entry_is_free(entry) || + entry->port != ti->port || + entry->type != ti->type) + return false; + + if (udp_tunnel_nic_entry_is_frozen(entry)) + return true; + + udp_tunnel_nic_entry_adj(utn, table, idx, use_cnt_adj); + return true; +} + +/* Try to find existing matching entry and adjust its use count, instead of + * adding a new one. Returns true if entry was found. In case of delete the + * entry may have gotten removed in the process, in which case it will be + * queued for removal. + */ +static bool +udp_tunnel_nic_try_existing(struct net_device *dev, struct udp_tunnel_nic *utn, + struct udp_tunnel_info *ti, int use_cnt_adj) +{ + const struct udp_tunnel_nic_table_info *table; + unsigned int i, j; + + for (i = 0; i < utn->n_tables; i++) { + table = &dev->udp_tunnel_nic_info->tables[i]; + if (!udp_tunnel_nic_table_is_capable(table, ti)) + continue; + + for (j = 0; j < table->n_entries; j++) + if (udp_tunnel_nic_entry_try_adj(utn, i, j, ti, + use_cnt_adj)) + return true; + } + + return false; +} + +static bool +udp_tunnel_nic_add_existing(struct net_device *dev, struct udp_tunnel_nic *utn, + struct udp_tunnel_info *ti) +{ + return udp_tunnel_nic_try_existing(dev, utn, ti, +1); +} + +static bool +udp_tunnel_nic_del_existing(struct net_device *dev, struct udp_tunnel_nic *utn, + struct udp_tunnel_info *ti) +{ + return udp_tunnel_nic_try_existing(dev, utn, ti, -1); +} + +static bool +udp_tunnel_nic_add_new(struct net_device *dev, struct udp_tunnel_nic *utn, + struct udp_tunnel_info *ti) +{ + const struct udp_tunnel_nic_table_info *table; + unsigned int i, j; + + for (i = 0; i < utn->n_tables; i++) { + table = &dev->udp_tunnel_nic_info->tables[i]; + if (!udp_tunnel_nic_table_is_capable(table, ti)) + continue; + + for (j = 0; j < table->n_entries; j++) { + struct udp_tunnel_nic_table_entry *entry; + + entry = &utn->entries[i][j]; + if (!udp_tunnel_nic_entry_is_free(entry)) + continue; + + entry->port = ti->port; + entry->type = ti->type; + entry->use_cnt = 1; + udp_tunnel_nic_entry_queue(utn, entry, + UDP_TUNNEL_NIC_ENTRY_ADD); + return true; + } + + /* The different table may still fit this port in, but there + * are no devices currently which have multiple tables accepting + * the same tunnel type, and false positives are okay. + */ + __set_bit(i, &utn->missed); + } + + return false; +} + +static void +__udp_tunnel_nic_add_port(struct net_device *dev, struct udp_tunnel_info *ti) +{ + const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; + struct udp_tunnel_nic *utn; + + utn = dev->udp_tunnel_nic; + if (!utn) + return; + if (!netif_running(dev) && info->flags & UDP_TUNNEL_NIC_INFO_OPEN_ONLY) + return; + if (info->flags & UDP_TUNNEL_NIC_INFO_STATIC_IANA_VXLAN && + ti->port == htons(IANA_VXLAN_UDP_PORT)) { + if (ti->type != UDP_TUNNEL_TYPE_VXLAN) + netdev_warn(dev, "device assumes port 4789 will be used by vxlan tunnels\n"); + return; + } + + if (!udp_tunnel_nic_is_capable(dev, utn, ti)) + return; + + /* It may happen that a tunnel of one type is removed and different + * tunnel type tries to reuse its port before the device was informed. + * Rely on utn->missed to re-add this port later. + */ + if (udp_tunnel_nic_has_collision(dev, utn, ti)) + return; + + if (!udp_tunnel_nic_add_existing(dev, utn, ti)) + udp_tunnel_nic_add_new(dev, utn, ti); + + udp_tunnel_nic_device_sync(dev, utn); +} + +static void +__udp_tunnel_nic_del_port(struct net_device *dev, struct udp_tunnel_info *ti) +{ + struct udp_tunnel_nic *utn; + + utn = dev->udp_tunnel_nic; + if (!utn) + return; + + if (!udp_tunnel_nic_is_capable(dev, utn, ti)) + return; + + udp_tunnel_nic_del_existing(dev, utn, ti); + + udp_tunnel_nic_device_sync(dev, utn); +} + +static void __udp_tunnel_nic_reset_ntf(struct net_device *dev) +{ + const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; + struct udp_tunnel_nic *utn; + unsigned int i, j; + + ASSERT_RTNL(); + + utn = dev->udp_tunnel_nic; + if (!utn) + return; + + utn->need_sync = false; + for (i = 0; i < utn->n_tables; i++) + for (j = 0; j < info->tables[i].n_entries; j++) { + struct udp_tunnel_nic_table_entry *entry; + + entry = &utn->entries[i][j]; + + entry->flags &= ~(UDP_TUNNEL_NIC_ENTRY_DEL | + UDP_TUNNEL_NIC_ENTRY_OP_FAIL); + /* We don't release rtnl across ops */ + WARN_ON(entry->flags & UDP_TUNNEL_NIC_ENTRY_FROZEN); + if (!entry->use_cnt) + continue; + + udp_tunnel_nic_entry_queue(utn, entry, + UDP_TUNNEL_NIC_ENTRY_ADD); + } + + __udp_tunnel_nic_device_sync(dev, utn); +} + +static size_t +__udp_tunnel_nic_dump_size(struct net_device *dev, unsigned int table) +{ + const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; + struct udp_tunnel_nic *utn; + unsigned int j; + size_t size; + + utn = dev->udp_tunnel_nic; + if (!utn) + return 0; + + size = 0; + for (j = 0; j < info->tables[table].n_entries; j++) { + if (!udp_tunnel_nic_entry_is_present(&utn->entries[table][j])) + continue; + + size += nla_total_size(0) + /* _TABLE_ENTRY */ + nla_total_size(sizeof(__be16)) + /* _ENTRY_PORT */ + nla_total_size(sizeof(u32)); /* _ENTRY_TYPE */ + } + + return size; +} + +static int +__udp_tunnel_nic_dump_write(struct net_device *dev, unsigned int table, + struct sk_buff *skb) +{ + const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; + struct udp_tunnel_nic *utn; + struct nlattr *nest; + unsigned int j; + + utn = dev->udp_tunnel_nic; + if (!utn) + return 0; + + for (j = 0; j < info->tables[table].n_entries; j++) { + if (!udp_tunnel_nic_entry_is_present(&utn->entries[table][j])) + continue; + + nest = nla_nest_start(skb, ETHTOOL_A_TUNNEL_UDP_TABLE_ENTRY); + + if (nla_put_be16(skb, ETHTOOL_A_TUNNEL_UDP_ENTRY_PORT, + utn->entries[table][j].port) || + nla_put_u32(skb, ETHTOOL_A_TUNNEL_UDP_ENTRY_TYPE, + ilog2(utn->entries[table][j].type))) + goto err_cancel; + + nla_nest_end(skb, nest); + } + + return 0; + +err_cancel: + nla_nest_cancel(skb, nest); + return -EMSGSIZE; +} + +static const struct udp_tunnel_nic_ops __udp_tunnel_nic_ops = { + .get_port = __udp_tunnel_nic_get_port, + .set_port_priv = __udp_tunnel_nic_set_port_priv, + .add_port = __udp_tunnel_nic_add_port, + .del_port = __udp_tunnel_nic_del_port, + .reset_ntf = __udp_tunnel_nic_reset_ntf, + .dump_size = __udp_tunnel_nic_dump_size, + .dump_write = __udp_tunnel_nic_dump_write, +}; + +static void +udp_tunnel_nic_flush(struct net_device *dev, struct udp_tunnel_nic *utn) +{ + const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; + unsigned int i, j; + + for (i = 0; i < utn->n_tables; i++) + for (j = 0; j < info->tables[i].n_entries; j++) { + int adj_cnt = -utn->entries[i][j].use_cnt; + + if (adj_cnt) + udp_tunnel_nic_entry_adj(utn, i, j, adj_cnt); + } + + __udp_tunnel_nic_device_sync(dev, utn); + + for (i = 0; i < utn->n_tables; i++) + memset(utn->entries[i], 0, array_size(info->tables[i].n_entries, + sizeof(**utn->entries))); + WARN_ON(utn->need_sync); + utn->need_replay = 0; +} + +static void +udp_tunnel_nic_replay(struct net_device *dev, struct udp_tunnel_nic *utn) +{ + const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; + struct udp_tunnel_nic_shared_node *node; + unsigned int i, j; + + /* Freeze all the ports we are already tracking so that the replay + * does not double up the refcount. + */ + for (i = 0; i < utn->n_tables; i++) + for (j = 0; j < info->tables[i].n_entries; j++) + udp_tunnel_nic_entry_freeze_used(&utn->entries[i][j]); + utn->missed = 0; + utn->need_replay = 0; + + if (!info->shared) { + udp_tunnel_get_rx_info(dev); + } else { + list_for_each_entry(node, &info->shared->devices, list) + udp_tunnel_get_rx_info(node->dev); + } + + for (i = 0; i < utn->n_tables; i++) + for (j = 0; j < info->tables[i].n_entries; j++) + udp_tunnel_nic_entry_unfreeze(&utn->entries[i][j]); +} + +static void udp_tunnel_nic_device_sync_work(struct work_struct *work) +{ + struct udp_tunnel_nic *utn = + container_of(work, struct udp_tunnel_nic, work); + + rtnl_lock(); + utn->work_pending = 0; + __udp_tunnel_nic_device_sync(utn->dev, utn); + + if (utn->need_replay) + udp_tunnel_nic_replay(utn->dev, utn); + rtnl_unlock(); +} + +static struct udp_tunnel_nic * +udp_tunnel_nic_alloc(const struct udp_tunnel_nic_info *info, + unsigned int n_tables) +{ + struct udp_tunnel_nic *utn; + unsigned int i; + + utn = kzalloc(sizeof(*utn), GFP_KERNEL); + if (!utn) + return NULL; + utn->n_tables = n_tables; + INIT_WORK(&utn->work, udp_tunnel_nic_device_sync_work); + + utn->entries = kmalloc_array(n_tables, sizeof(void *), GFP_KERNEL); + if (!utn->entries) + goto err_free_utn; + + for (i = 0; i < n_tables; i++) { + utn->entries[i] = kcalloc(info->tables[i].n_entries, + sizeof(*utn->entries[i]), GFP_KERNEL); + if (!utn->entries[i]) + goto err_free_prev_entries; + } + + return utn; + +err_free_prev_entries: + while (i--) + kfree(utn->entries[i]); + kfree(utn->entries); +err_free_utn: + kfree(utn); + return NULL; +} + +static void udp_tunnel_nic_free(struct udp_tunnel_nic *utn) +{ + unsigned int i; + + for (i = 0; i < utn->n_tables; i++) + kfree(utn->entries[i]); + kfree(utn->entries); + kfree(utn); +} + +static int udp_tunnel_nic_register(struct net_device *dev) +{ + const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; + struct udp_tunnel_nic_shared_node *node = NULL; + struct udp_tunnel_nic *utn; + unsigned int n_tables, i; + + BUILD_BUG_ON(sizeof(utn->missed) * BITS_PER_BYTE < + UDP_TUNNEL_NIC_MAX_TABLES); + /* Expect use count of at most 2 (IPv4, IPv6) per device */ + BUILD_BUG_ON(UDP_TUNNEL_NIC_USE_CNT_MAX < + UDP_TUNNEL_NIC_MAX_SHARING_DEVICES * 2); + + /* Check that the driver info is sane */ + if (WARN_ON(!info->set_port != !info->unset_port) || + WARN_ON(!info->set_port == !info->sync_table) || + WARN_ON(!info->tables[0].n_entries)) + return -EINVAL; + + if (WARN_ON(info->shared && + info->flags & UDP_TUNNEL_NIC_INFO_OPEN_ONLY)) + return -EINVAL; + + n_tables = 1; + for (i = 1; i < UDP_TUNNEL_NIC_MAX_TABLES; i++) { + if (!info->tables[i].n_entries) + continue; + + n_tables++; + if (WARN_ON(!info->tables[i - 1].n_entries)) + return -EINVAL; + } + + /* Create UDP tunnel state structures */ + if (info->shared) { + node = kzalloc(sizeof(*node), GFP_KERNEL); + if (!node) + return -ENOMEM; + + node->dev = dev; + } + + if (info->shared && info->shared->udp_tunnel_nic_info) { + utn = info->shared->udp_tunnel_nic_info; + } else { + utn = udp_tunnel_nic_alloc(info, n_tables); + if (!utn) { + kfree(node); + return -ENOMEM; + } + } + + if (info->shared) { + if (!info->shared->udp_tunnel_nic_info) { + INIT_LIST_HEAD(&info->shared->devices); + info->shared->udp_tunnel_nic_info = utn; + } + + list_add_tail(&node->list, &info->shared->devices); + } + + utn->dev = dev; + dev_hold(dev); + dev->udp_tunnel_nic = utn; + + if (!(info->flags & UDP_TUNNEL_NIC_INFO_OPEN_ONLY)) + udp_tunnel_get_rx_info(dev); + + return 0; +} + +static void +udp_tunnel_nic_unregister(struct net_device *dev, struct udp_tunnel_nic *utn) +{ + const struct udp_tunnel_nic_info *info = dev->udp_tunnel_nic_info; + + /* For a shared table remove this dev from the list of sharing devices + * and if there are other devices just detach. + */ + if (info->shared) { + struct udp_tunnel_nic_shared_node *node, *first; + + list_for_each_entry(node, &info->shared->devices, list) + if (node->dev == dev) + break; + if (list_entry_is_head(node, &info->shared->devices, list)) + return; + + list_del(&node->list); + kfree(node); + + first = list_first_entry_or_null(&info->shared->devices, + typeof(*first), list); + if (first) { + udp_tunnel_drop_rx_info(dev); + utn->dev = first->dev; + goto release_dev; + } + + info->shared->udp_tunnel_nic_info = NULL; + } + + /* Flush before we check work, so we don't waste time adding entries + * from the work which we will boot immediately. + */ + udp_tunnel_nic_flush(dev, utn); + + /* Wait for the work to be done using the state, netdev core will + * retry unregister until we give up our reference on this device. + */ + if (utn->work_pending) + return; + + udp_tunnel_nic_free(utn); +release_dev: + dev->udp_tunnel_nic = NULL; + dev_put(dev); +} + +static int +udp_tunnel_nic_netdevice_event(struct notifier_block *unused, + unsigned long event, void *ptr) +{ + struct net_device *dev = netdev_notifier_info_to_dev(ptr); + const struct udp_tunnel_nic_info *info; + struct udp_tunnel_nic *utn; + + info = dev->udp_tunnel_nic_info; + if (!info) + return NOTIFY_DONE; + + if (event == NETDEV_REGISTER) { + int err; + + err = udp_tunnel_nic_register(dev); + if (err) + netdev_WARN(dev, "failed to register for UDP tunnel offloads: %d", err); + return notifier_from_errno(err); + } + /* All other events will need the udp_tunnel_nic state */ + utn = dev->udp_tunnel_nic; + if (!utn) + return NOTIFY_DONE; + + if (event == NETDEV_UNREGISTER) { + udp_tunnel_nic_unregister(dev, utn); + return NOTIFY_OK; + } + + /* All other events only matter if NIC has to be programmed open */ + if (!(info->flags & UDP_TUNNEL_NIC_INFO_OPEN_ONLY)) + return NOTIFY_DONE; + + if (event == NETDEV_UP) { + WARN_ON(!udp_tunnel_nic_is_empty(dev, utn)); + udp_tunnel_get_rx_info(dev); + return NOTIFY_OK; + } + if (event == NETDEV_GOING_DOWN) { + udp_tunnel_nic_flush(dev, utn); + return NOTIFY_OK; + } + + return NOTIFY_DONE; +} + +static struct notifier_block udp_tunnel_nic_notifier_block __read_mostly = { + .notifier_call = udp_tunnel_nic_netdevice_event, +}; + +static int __init udp_tunnel_nic_init_module(void) +{ + int err; + + udp_tunnel_nic_workqueue = alloc_ordered_workqueue("udp_tunnel_nic", 0); + if (!udp_tunnel_nic_workqueue) + return -ENOMEM; + + rtnl_lock(); + udp_tunnel_nic_ops = &__udp_tunnel_nic_ops; + rtnl_unlock(); + + err = register_netdevice_notifier(&udp_tunnel_nic_notifier_block); + if (err) + goto err_unset_ops; + + return 0; + +err_unset_ops: + rtnl_lock(); + udp_tunnel_nic_ops = NULL; + rtnl_unlock(); + destroy_workqueue(udp_tunnel_nic_workqueue); + return err; +} +late_initcall(udp_tunnel_nic_init_module); + +static void __exit udp_tunnel_nic_cleanup_module(void) +{ + unregister_netdevice_notifier(&udp_tunnel_nic_notifier_block); + + rtnl_lock(); + udp_tunnel_nic_ops = NULL; + rtnl_unlock(); + + destroy_workqueue(udp_tunnel_nic_workqueue); +} +module_exit(udp_tunnel_nic_cleanup_module); + +MODULE_LICENSE("GPL"); |