| // SPDX-License-Identifier: GPL-2.0 |
| /* XDP sockets |
| * |
| * AF_XDP sockets allows a channel between XDP programs and userspace |
| * applications. |
| * Copyright(c) 2018 Intel Corporation. |
| * |
| * Author(s): Björn Töpel <bjorn.topel@intel.com> |
| * Magnus Karlsson <magnus.karlsson@intel.com> |
| */ |
| |
| #define pr_fmt(fmt) "AF_XDP: %s: " fmt, __func__ |
| |
| #include <linux/if_xdp.h> |
| #include <linux/init.h> |
| #include <linux/sched/mm.h> |
| #include <linux/sched/signal.h> |
| #include <linux/sched/task.h> |
| #include <linux/socket.h> |
| #include <linux/file.h> |
| #include <linux/uaccess.h> |
| #include <linux/net.h> |
| #include <linux/netdevice.h> |
| #include <linux/rculist.h> |
| #include <net/xdp_sock.h> |
| #include <net/xdp.h> |
| |
| #include "xsk_queue.h" |
| #include "xdp_umem.h" |
| #include "xsk.h" |
| |
| #define TX_BATCH_SIZE 16 |
| |
| static DEFINE_PER_CPU(struct list_head, xskmap_flush_list); |
| |
| bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs) |
| { |
| return READ_ONCE(xs->rx) && READ_ONCE(xs->umem) && |
| READ_ONCE(xs->umem->fq); |
| } |
| |
| bool xsk_umem_has_addrs(struct xdp_umem *umem, u32 cnt) |
| { |
| return xskq_cons_has_entries(umem->fq, cnt); |
| } |
| EXPORT_SYMBOL(xsk_umem_has_addrs); |
| |
| bool xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr) |
| { |
| return xskq_cons_peek_addr(umem->fq, addr, umem); |
| } |
| EXPORT_SYMBOL(xsk_umem_peek_addr); |
| |
| void xsk_umem_release_addr(struct xdp_umem *umem) |
| { |
| xskq_cons_release(umem->fq); |
| } |
| EXPORT_SYMBOL(xsk_umem_release_addr); |
| |
| void xsk_set_rx_need_wakeup(struct xdp_umem *umem) |
| { |
| if (umem->need_wakeup & XDP_WAKEUP_RX) |
| return; |
| |
| umem->fq->ring->flags |= XDP_RING_NEED_WAKEUP; |
| umem->need_wakeup |= XDP_WAKEUP_RX; |
| } |
| EXPORT_SYMBOL(xsk_set_rx_need_wakeup); |
| |
| void xsk_set_tx_need_wakeup(struct xdp_umem *umem) |
| { |
| struct xdp_sock *xs; |
| |
| if (umem->need_wakeup & XDP_WAKEUP_TX) |
| return; |
| |
| rcu_read_lock(); |
| list_for_each_entry_rcu(xs, &umem->xsk_list, list) { |
| xs->tx->ring->flags |= XDP_RING_NEED_WAKEUP; |
| } |
| rcu_read_unlock(); |
| |
| umem->need_wakeup |= XDP_WAKEUP_TX; |
| } |
| EXPORT_SYMBOL(xsk_set_tx_need_wakeup); |
| |
| void xsk_clear_rx_need_wakeup(struct xdp_umem *umem) |
| { |
| if (!(umem->need_wakeup & XDP_WAKEUP_RX)) |
| return; |
| |
| umem->fq->ring->flags &= ~XDP_RING_NEED_WAKEUP; |
| umem->need_wakeup &= ~XDP_WAKEUP_RX; |
| } |
| EXPORT_SYMBOL(xsk_clear_rx_need_wakeup); |
| |
| void xsk_clear_tx_need_wakeup(struct xdp_umem *umem) |
| { |
| struct xdp_sock *xs; |
| |
| if (!(umem->need_wakeup & XDP_WAKEUP_TX)) |
| return; |
| |
| rcu_read_lock(); |
| list_for_each_entry_rcu(xs, &umem->xsk_list, list) { |
| xs->tx->ring->flags &= ~XDP_RING_NEED_WAKEUP; |
| } |
| rcu_read_unlock(); |
| |
| umem->need_wakeup &= ~XDP_WAKEUP_TX; |
| } |
| EXPORT_SYMBOL(xsk_clear_tx_need_wakeup); |
| |
| bool xsk_umem_uses_need_wakeup(struct xdp_umem *umem) |
| { |
| return umem->flags & XDP_UMEM_USES_NEED_WAKEUP; |
| } |
| EXPORT_SYMBOL(xsk_umem_uses_need_wakeup); |
| |
| /* If a buffer crosses a page boundary, we need to do 2 memcpy's, one for |
| * each page. This is only required in copy mode. |
| */ |
| static void __xsk_rcv_memcpy(struct xdp_umem *umem, u64 addr, void *from_buf, |
| u32 len, u32 metalen) |
| { |
| void *to_buf = xdp_umem_get_data(umem, addr); |
| |
| addr = xsk_umem_add_offset_to_addr(addr); |
| if (xskq_cons_crosses_non_contig_pg(umem, addr, len + metalen)) { |
| void *next_pg_addr = umem->pages[(addr >> PAGE_SHIFT) + 1].addr; |
| u64 page_start = addr & ~(PAGE_SIZE - 1); |
| u64 first_len = PAGE_SIZE - (addr - page_start); |
| |
| memcpy(to_buf, from_buf, first_len + metalen); |
| memcpy(next_pg_addr, from_buf + first_len, len - first_len); |
| |
| return; |
| } |
| |
| memcpy(to_buf, from_buf, len + metalen); |
| } |
| |
| static int __xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp, u32 len) |
| { |
| u64 offset = xs->umem->headroom; |
| u64 addr, memcpy_addr; |
| void *from_buf; |
| u32 metalen; |
| int err; |
| |
| if (!xskq_cons_peek_addr(xs->umem->fq, &addr, xs->umem) || |
| len > xs->umem->chunk_size_nohr - XDP_PACKET_HEADROOM) { |
| xs->rx_dropped++; |
| return -ENOSPC; |
| } |
| |
| if (unlikely(xdp_data_meta_unsupported(xdp))) { |
| from_buf = xdp->data; |
| metalen = 0; |
| } else { |
| from_buf = xdp->data_meta; |
| metalen = xdp->data - xdp->data_meta; |
| } |
| |
| memcpy_addr = xsk_umem_adjust_offset(xs->umem, addr, offset); |
| __xsk_rcv_memcpy(xs->umem, memcpy_addr, from_buf, len, metalen); |
| |
| offset += metalen; |
| addr = xsk_umem_adjust_offset(xs->umem, addr, offset); |
| err = xskq_prod_reserve_desc(xs->rx, addr, len); |
| if (!err) { |
| xskq_cons_release(xs->umem->fq); |
| xdp_return_buff(xdp); |
| return 0; |
| } |
| |
| xs->rx_dropped++; |
| return err; |
| } |
| |
| static int __xsk_rcv_zc(struct xdp_sock *xs, struct xdp_buff *xdp, u32 len) |
| { |
| int err = xskq_prod_reserve_desc(xs->rx, xdp->handle, len); |
| |
| if (err) |
| xs->rx_dropped++; |
| |
| return err; |
| } |
| |
| static bool xsk_is_bound(struct xdp_sock *xs) |
| { |
| if (READ_ONCE(xs->state) == XSK_BOUND) { |
| /* Matches smp_wmb() in bind(). */ |
| smp_rmb(); |
| return true; |
| } |
| return false; |
| } |
| |
| static int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp) |
| { |
| u32 len; |
| |
| if (!xsk_is_bound(xs)) |
| return -EINVAL; |
| |
| if (xs->dev != xdp->rxq->dev || xs->queue_id != xdp->rxq->queue_index) |
| return -EINVAL; |
| |
| len = xdp->data_end - xdp->data; |
| |
| return (xdp->rxq->mem.type == MEM_TYPE_ZERO_COPY) ? |
| __xsk_rcv_zc(xs, xdp, len) : __xsk_rcv(xs, xdp, len); |
| } |
| |
| static void xsk_flush(struct xdp_sock *xs) |
| { |
| xskq_prod_submit(xs->rx); |
| __xskq_cons_release(xs->umem->fq); |
| sock_def_readable(&xs->sk); |
| } |
| |
| int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp) |
| { |
| u32 metalen = xdp->data - xdp->data_meta; |
| u32 len = xdp->data_end - xdp->data; |
| u64 offset = xs->umem->headroom; |
| void *buffer; |
| u64 addr; |
| int err; |
| |
| spin_lock_bh(&xs->rx_lock); |
| |
| if (xs->dev != xdp->rxq->dev || xs->queue_id != xdp->rxq->queue_index) { |
| err = -EINVAL; |
| goto out_unlock; |
| } |
| |
| if (!xskq_cons_peek_addr(xs->umem->fq, &addr, xs->umem) || |
| len > xs->umem->chunk_size_nohr - XDP_PACKET_HEADROOM) { |
| err = -ENOSPC; |
| goto out_drop; |
| } |
| |
| addr = xsk_umem_adjust_offset(xs->umem, addr, offset); |
| buffer = xdp_umem_get_data(xs->umem, addr); |
| memcpy(buffer, xdp->data_meta, len + metalen); |
| |
| addr = xsk_umem_adjust_offset(xs->umem, addr, metalen); |
| err = xskq_prod_reserve_desc(xs->rx, addr, len); |
| if (err) |
| goto out_drop; |
| |
| xskq_cons_release(xs->umem->fq); |
| xskq_prod_submit(xs->rx); |
| |
| spin_unlock_bh(&xs->rx_lock); |
| |
| xs->sk.sk_data_ready(&xs->sk); |
| return 0; |
| |
| out_drop: |
| xs->rx_dropped++; |
| out_unlock: |
| spin_unlock_bh(&xs->rx_lock); |
| return err; |
| } |
| |
| int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp) |
| { |
| struct list_head *flush_list = this_cpu_ptr(&xskmap_flush_list); |
| int err; |
| |
| err = xsk_rcv(xs, xdp); |
| if (err) |
| return err; |
| |
| if (!xs->flush_node.prev) |
| list_add(&xs->flush_node, flush_list); |
| |
| return 0; |
| } |
| |
| void __xsk_map_flush(void) |
| { |
| struct list_head *flush_list = this_cpu_ptr(&xskmap_flush_list); |
| struct xdp_sock *xs, *tmp; |
| |
| list_for_each_entry_safe(xs, tmp, flush_list, flush_node) { |
| xsk_flush(xs); |
| __list_del_clearprev(&xs->flush_node); |
| } |
| } |
| |
| void xsk_umem_complete_tx(struct xdp_umem *umem, u32 nb_entries) |
| { |
| xskq_prod_submit_n(umem->cq, nb_entries); |
| } |
| EXPORT_SYMBOL(xsk_umem_complete_tx); |
| |
| void xsk_umem_consume_tx_done(struct xdp_umem *umem) |
| { |
| struct xdp_sock *xs; |
| |
| rcu_read_lock(); |
| list_for_each_entry_rcu(xs, &umem->xsk_list, list) { |
| __xskq_cons_release(xs->tx); |
| xs->sk.sk_write_space(&xs->sk); |
| } |
| rcu_read_unlock(); |
| } |
| EXPORT_SYMBOL(xsk_umem_consume_tx_done); |
| |
| bool xsk_umem_consume_tx(struct xdp_umem *umem, struct xdp_desc *desc) |
| { |
| struct xdp_sock *xs; |
| |
| rcu_read_lock(); |
| list_for_each_entry_rcu(xs, &umem->xsk_list, list) { |
| if (!xskq_cons_peek_desc(xs->tx, desc, umem)) |
| continue; |
| |
| /* This is the backpreassure mechanism for the Tx path. |
| * Reserve space in the completion queue and only proceed |
| * if there is space in it. This avoids having to implement |
| * any buffering in the Tx path. |
| */ |
| if (xskq_prod_reserve_addr(umem->cq, desc->addr)) |
| goto out; |
| |
| xskq_cons_release(xs->tx); |
| rcu_read_unlock(); |
| return true; |
| } |
| |
| out: |
| rcu_read_unlock(); |
| return false; |
| } |
| EXPORT_SYMBOL(xsk_umem_consume_tx); |
| |
| static int xsk_wakeup(struct xdp_sock *xs, u8 flags) |
| { |
| struct net_device *dev = xs->dev; |
| int err; |
| |
| rcu_read_lock(); |
| err = dev->netdev_ops->ndo_xsk_wakeup(dev, xs->queue_id, flags); |
| rcu_read_unlock(); |
| |
| return err; |
| } |
| |
| static int xsk_zc_xmit(struct xdp_sock *xs) |
| { |
| return xsk_wakeup(xs, XDP_WAKEUP_TX); |
| } |
| |
| static void xsk_destruct_skb(struct sk_buff *skb) |
| { |
| u64 addr = (u64)(long)skb_shinfo(skb)->destructor_arg; |
| struct xdp_sock *xs = xdp_sk(skb->sk); |
| unsigned long flags; |
| |
| spin_lock_irqsave(&xs->tx_completion_lock, flags); |
| xskq_prod_submit_addr(xs->umem->cq, addr); |
| spin_unlock_irqrestore(&xs->tx_completion_lock, flags); |
| |
| sock_wfree(skb); |
| } |
| |
| static int xsk_generic_xmit(struct sock *sk) |
| { |
| struct xdp_sock *xs = xdp_sk(sk); |
| u32 max_batch = TX_BATCH_SIZE; |
| bool sent_frame = false; |
| struct xdp_desc desc; |
| struct sk_buff *skb; |
| int err = 0; |
| |
| mutex_lock(&xs->mutex); |
| |
| if (xs->queue_id >= xs->dev->real_num_tx_queues) |
| goto out; |
| |
| while (xskq_cons_peek_desc(xs->tx, &desc, xs->umem)) { |
| char *buffer; |
| u64 addr; |
| u32 len; |
| |
| if (max_batch-- == 0) { |
| err = -EAGAIN; |
| goto out; |
| } |
| |
| len = desc.len; |
| skb = sock_alloc_send_skb(sk, len, 1, &err); |
| if (unlikely(!skb)) { |
| err = -EAGAIN; |
| goto out; |
| } |
| |
| skb_put(skb, len); |
| addr = desc.addr; |
| buffer = xdp_umem_get_data(xs->umem, addr); |
| err = skb_store_bits(skb, 0, buffer, len); |
| /* This is the backpreassure mechanism for the Tx path. |
| * Reserve space in the completion queue and only proceed |
| * if there is space in it. This avoids having to implement |
| * any buffering in the Tx path. |
| */ |
| if (unlikely(err) || xskq_prod_reserve(xs->umem->cq)) { |
| kfree_skb(skb); |
| goto out; |
| } |
| |
| skb->dev = xs->dev; |
| skb->priority = sk->sk_priority; |
| skb->mark = sk->sk_mark; |
| skb_shinfo(skb)->destructor_arg = (void *)(long)desc.addr; |
| skb->destructor = xsk_destruct_skb; |
| |
| err = dev_direct_xmit(skb, xs->queue_id); |
| xskq_cons_release(xs->tx); |
| /* Ignore NET_XMIT_CN as packet might have been sent */ |
| if (err == NET_XMIT_DROP || err == NETDEV_TX_BUSY) { |
| /* SKB completed but not sent */ |
| err = -EBUSY; |
| goto out; |
| } |
| |
| sent_frame = true; |
| } |
| |
| out: |
| if (sent_frame) |
| sk->sk_write_space(sk); |
| |
| mutex_unlock(&xs->mutex); |
| return err; |
| } |
| |
| static int __xsk_sendmsg(struct sock *sk) |
| { |
| struct xdp_sock *xs = xdp_sk(sk); |
| |
| if (unlikely(!(xs->dev->flags & IFF_UP))) |
| return -ENETDOWN; |
| if (unlikely(!xs->tx)) |
| return -ENOBUFS; |
| |
| return xs->zc ? xsk_zc_xmit(xs) : xsk_generic_xmit(sk); |
| } |
| |
| static int xsk_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) |
| { |
| bool need_wait = !(m->msg_flags & MSG_DONTWAIT); |
| struct sock *sk = sock->sk; |
| struct xdp_sock *xs = xdp_sk(sk); |
| |
| if (unlikely(!xsk_is_bound(xs))) |
| return -ENXIO; |
| if (unlikely(need_wait)) |
| return -EOPNOTSUPP; |
| |
| return __xsk_sendmsg(sk); |
| } |
| |
| static __poll_t xsk_poll(struct file *file, struct socket *sock, |
| struct poll_table_struct *wait) |
| { |
| __poll_t mask = datagram_poll(file, sock, wait); |
| struct sock *sk = sock->sk; |
| struct xdp_sock *xs = xdp_sk(sk); |
| struct xdp_umem *umem; |
| |
| if (unlikely(!xsk_is_bound(xs))) |
| return mask; |
| |
| umem = xs->umem; |
| |
| if (umem->need_wakeup) { |
| if (xs->zc) |
| xsk_wakeup(xs, umem->need_wakeup); |
| else |
| /* Poll needs to drive Tx also in copy mode */ |
| __xsk_sendmsg(sk); |
| } |
| |
| if (xs->rx && !xskq_prod_is_empty(xs->rx)) |
| mask |= EPOLLIN | EPOLLRDNORM; |
| if (xs->tx && !xskq_cons_is_full(xs->tx)) |
| mask |= EPOLLOUT | EPOLLWRNORM; |
| |
| return mask; |
| } |
| |
| static int xsk_init_queue(u32 entries, struct xsk_queue **queue, |
| bool umem_queue) |
| { |
| struct xsk_queue *q; |
| |
| if (entries == 0 || *queue || !is_power_of_2(entries)) |
| return -EINVAL; |
| |
| q = xskq_create(entries, umem_queue); |
| if (!q) |
| return -ENOMEM; |
| |
| /* Make sure queue is ready before it can be seen by others */ |
| smp_wmb(); |
| WRITE_ONCE(*queue, q); |
| return 0; |
| } |
| |
| static void xsk_unbind_dev(struct xdp_sock *xs) |
| { |
| struct net_device *dev = xs->dev; |
| |
| if (xs->state != XSK_BOUND) |
| return; |
| WRITE_ONCE(xs->state, XSK_UNBOUND); |
| |
| /* Wait for driver to stop using the xdp socket. */ |
| xdp_del_sk_umem(xs->umem, xs); |
| xs->dev = NULL; |
| synchronize_net(); |
| dev_put(dev); |
| } |
| |
| static struct xsk_map *xsk_get_map_list_entry(struct xdp_sock *xs, |
| struct xdp_sock ***map_entry) |
| { |
| struct xsk_map *map = NULL; |
| struct xsk_map_node *node; |
| |
| *map_entry = NULL; |
| |
| spin_lock_bh(&xs->map_list_lock); |
| node = list_first_entry_or_null(&xs->map_list, struct xsk_map_node, |
| node); |
| if (node) { |
| WARN_ON(xsk_map_inc(node->map)); |
| map = node->map; |
| *map_entry = node->map_entry; |
| } |
| spin_unlock_bh(&xs->map_list_lock); |
| return map; |
| } |
| |
| static void xsk_delete_from_maps(struct xdp_sock *xs) |
| { |
| /* This function removes the current XDP socket from all the |
| * maps it resides in. We need to take extra care here, due to |
| * the two locks involved. Each map has a lock synchronizing |
| * updates to the entries, and each socket has a lock that |
| * synchronizes access to the list of maps (map_list). For |
| * deadlock avoidance the locks need to be taken in the order |
| * "map lock"->"socket map list lock". We start off by |
| * accessing the socket map list, and take a reference to the |
| * map to guarantee existence between the |
| * xsk_get_map_list_entry() and xsk_map_try_sock_delete() |
| * calls. Then we ask the map to remove the socket, which |
| * tries to remove the socket from the map. Note that there |
| * might be updates to the map between |
| * xsk_get_map_list_entry() and xsk_map_try_sock_delete(). |
| */ |
| struct xdp_sock **map_entry = NULL; |
| struct xsk_map *map; |
| |
| while ((map = xsk_get_map_list_entry(xs, &map_entry))) { |
| xsk_map_try_sock_delete(map, xs, map_entry); |
| xsk_map_put(map); |
| } |
| } |
| |
| static int xsk_release(struct socket *sock) |
| { |
| struct sock *sk = sock->sk; |
| struct xdp_sock *xs = xdp_sk(sk); |
| struct net *net; |
| |
| if (!sk) |
| return 0; |
| |
| net = sock_net(sk); |
| |
| mutex_lock(&net->xdp.lock); |
| sk_del_node_init_rcu(sk); |
| mutex_unlock(&net->xdp.lock); |
| |
| local_bh_disable(); |
| sock_prot_inuse_add(net, sk->sk_prot, -1); |
| local_bh_enable(); |
| |
| xsk_delete_from_maps(xs); |
| mutex_lock(&xs->mutex); |
| xsk_unbind_dev(xs); |
| mutex_unlock(&xs->mutex); |
| |
| xskq_destroy(xs->rx); |
| xskq_destroy(xs->tx); |
| |
| sock_orphan(sk); |
| sock->sk = NULL; |
| |
| sk_refcnt_debug_release(sk); |
| sock_put(sk); |
| |
| return 0; |
| } |
| |
| static struct socket *xsk_lookup_xsk_from_fd(int fd) |
| { |
| struct socket *sock; |
| int err; |
| |
| sock = sockfd_lookup(fd, &err); |
| if (!sock) |
| return ERR_PTR(-ENOTSOCK); |
| |
| if (sock->sk->sk_family != PF_XDP) { |
| sockfd_put(sock); |
| return ERR_PTR(-ENOPROTOOPT); |
| } |
| |
| return sock; |
| } |
| |
| /* Check if umem pages are contiguous. |
| * If zero-copy mode, use the DMA address to do the page contiguity check |
| * For all other modes we use addr (kernel virtual address) |
| * Store the result in the low bits of addr. |
| */ |
| static void xsk_check_page_contiguity(struct xdp_umem *umem, u32 flags) |
| { |
| struct xdp_umem_page *pgs = umem->pages; |
| int i, is_contig; |
| |
| for (i = 0; i < umem->npgs - 1; i++) { |
| is_contig = (flags & XDP_ZEROCOPY) ? |
| (pgs[i].dma + PAGE_SIZE == pgs[i + 1].dma) : |
| (pgs[i].addr + PAGE_SIZE == pgs[i + 1].addr); |
| pgs[i].addr += is_contig << XSK_NEXT_PG_CONTIG_SHIFT; |
| } |
| } |
| |
| static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len) |
| { |
| struct sockaddr_xdp *sxdp = (struct sockaddr_xdp *)addr; |
| struct sock *sk = sock->sk; |
| struct xdp_sock *xs = xdp_sk(sk); |
| struct net_device *dev; |
| u32 flags, qid; |
| int err = 0; |
| |
| if (addr_len < sizeof(struct sockaddr_xdp)) |
| return -EINVAL; |
| if (sxdp->sxdp_family != AF_XDP) |
| return -EINVAL; |
| |
| flags = sxdp->sxdp_flags; |
| if (flags & ~(XDP_SHARED_UMEM | XDP_COPY | XDP_ZEROCOPY | |
| XDP_USE_NEED_WAKEUP)) |
| return -EINVAL; |
| |
| rtnl_lock(); |
| mutex_lock(&xs->mutex); |
| if (xs->state != XSK_READY) { |
| err = -EBUSY; |
| goto out_release; |
| } |
| |
| dev = dev_get_by_index(sock_net(sk), sxdp->sxdp_ifindex); |
| if (!dev) { |
| err = -ENODEV; |
| goto out_release; |
| } |
| |
| if (!xs->rx && !xs->tx) { |
| err = -EINVAL; |
| goto out_unlock; |
| } |
| |
| qid = sxdp->sxdp_queue_id; |
| |
| if (flags & XDP_SHARED_UMEM) { |
| struct xdp_sock *umem_xs; |
| struct socket *sock; |
| |
| if ((flags & XDP_COPY) || (flags & XDP_ZEROCOPY) || |
| (flags & XDP_USE_NEED_WAKEUP)) { |
| /* Cannot specify flags for shared sockets. */ |
| err = -EINVAL; |
| goto out_unlock; |
| } |
| |
| if (xs->umem) { |
| /* We have already our own. */ |
| err = -EINVAL; |
| goto out_unlock; |
| } |
| |
| sock = xsk_lookup_xsk_from_fd(sxdp->sxdp_shared_umem_fd); |
| if (IS_ERR(sock)) { |
| err = PTR_ERR(sock); |
| goto out_unlock; |
| } |
| |
| umem_xs = xdp_sk(sock->sk); |
| if (!xsk_is_bound(umem_xs)) { |
| err = -EBADF; |
| sockfd_put(sock); |
| goto out_unlock; |
| } |
| if (umem_xs->dev != dev || umem_xs->queue_id != qid) { |
| err = -EINVAL; |
| sockfd_put(sock); |
| goto out_unlock; |
| } |
| |
| xdp_get_umem(umem_xs->umem); |
| WRITE_ONCE(xs->umem, umem_xs->umem); |
| sockfd_put(sock); |
| } else if (!xs->umem || !xdp_umem_validate_queues(xs->umem)) { |
| err = -EINVAL; |
| goto out_unlock; |
| } else { |
| /* This xsk has its own umem. */ |
| xskq_set_umem(xs->umem->fq, xs->umem->size, |
| xs->umem->chunk_mask); |
| xskq_set_umem(xs->umem->cq, xs->umem->size, |
| xs->umem->chunk_mask); |
| |
| err = xdp_umem_assign_dev(xs->umem, dev, qid, flags); |
| if (err) |
| goto out_unlock; |
| |
| xsk_check_page_contiguity(xs->umem, flags); |
| } |
| |
| xs->dev = dev; |
| xs->zc = xs->umem->zc; |
| xs->queue_id = qid; |
| xskq_set_umem(xs->rx, xs->umem->size, xs->umem->chunk_mask); |
| xskq_set_umem(xs->tx, xs->umem->size, xs->umem->chunk_mask); |
| xdp_add_sk_umem(xs->umem, xs); |
| |
| out_unlock: |
| if (err) { |
| dev_put(dev); |
| } else { |
| /* Matches smp_rmb() in bind() for shared umem |
| * sockets, and xsk_is_bound(). |
| */ |
| smp_wmb(); |
| WRITE_ONCE(xs->state, XSK_BOUND); |
| } |
| out_release: |
| mutex_unlock(&xs->mutex); |
| rtnl_unlock(); |
| return err; |
| } |
| |
| struct xdp_umem_reg_v1 { |
| __u64 addr; /* Start of packet data area */ |
| __u64 len; /* Length of packet data area */ |
| __u32 chunk_size; |
| __u32 headroom; |
| }; |
| |
| static int xsk_setsockopt(struct socket *sock, int level, int optname, |
| char __user *optval, unsigned int optlen) |
| { |
| struct sock *sk = sock->sk; |
| struct xdp_sock *xs = xdp_sk(sk); |
| int err; |
| |
| if (level != SOL_XDP) |
| return -ENOPROTOOPT; |
| |
| switch (optname) { |
| case XDP_RX_RING: |
| case XDP_TX_RING: |
| { |
| struct xsk_queue **q; |
| int entries; |
| |
| if (optlen < sizeof(entries)) |
| return -EINVAL; |
| if (copy_from_user(&entries, optval, sizeof(entries))) |
| return -EFAULT; |
| |
| mutex_lock(&xs->mutex); |
| if (xs->state != XSK_READY) { |
| mutex_unlock(&xs->mutex); |
| return -EBUSY; |
| } |
| q = (optname == XDP_TX_RING) ? &xs->tx : &xs->rx; |
| err = xsk_init_queue(entries, q, false); |
| if (!err && optname == XDP_TX_RING) |
| /* Tx needs to be explicitly woken up the first time */ |
| xs->tx->ring->flags |= XDP_RING_NEED_WAKEUP; |
| mutex_unlock(&xs->mutex); |
| return err; |
| } |
| case XDP_UMEM_REG: |
| { |
| size_t mr_size = sizeof(struct xdp_umem_reg); |
| struct xdp_umem_reg mr = {}; |
| struct xdp_umem *umem; |
| |
| if (optlen < sizeof(struct xdp_umem_reg_v1)) |
| return -EINVAL; |
| else if (optlen < sizeof(mr)) |
| mr_size = sizeof(struct xdp_umem_reg_v1); |
| |
| if (copy_from_user(&mr, optval, mr_size)) |
| return -EFAULT; |
| |
| mutex_lock(&xs->mutex); |
| if (xs->state != XSK_READY || xs->umem) { |
| mutex_unlock(&xs->mutex); |
| return -EBUSY; |
| } |
| |
| umem = xdp_umem_create(&mr); |
| if (IS_ERR(umem)) { |
| mutex_unlock(&xs->mutex); |
| return PTR_ERR(umem); |
| } |
| |
| /* Make sure umem is ready before it can be seen by others */ |
| smp_wmb(); |
| WRITE_ONCE(xs->umem, umem); |
| mutex_unlock(&xs->mutex); |
| return 0; |
| } |
| case XDP_UMEM_FILL_RING: |
| case XDP_UMEM_COMPLETION_RING: |
| { |
| struct xsk_queue **q; |
| int entries; |
| |
| if (copy_from_user(&entries, optval, sizeof(entries))) |
| return -EFAULT; |
| |
| mutex_lock(&xs->mutex); |
| if (xs->state != XSK_READY) { |
| mutex_unlock(&xs->mutex); |
| return -EBUSY; |
| } |
| if (!xs->umem) { |
| mutex_unlock(&xs->mutex); |
| return -EINVAL; |
| } |
| |
| q = (optname == XDP_UMEM_FILL_RING) ? &xs->umem->fq : |
| &xs->umem->cq; |
| err = xsk_init_queue(entries, q, true); |
| mutex_unlock(&xs->mutex); |
| return err; |
| } |
| default: |
| break; |
| } |
| |
| return -ENOPROTOOPT; |
| } |
| |
| static void xsk_enter_rxtx_offsets(struct xdp_ring_offset_v1 *ring) |
| { |
| ring->producer = offsetof(struct xdp_rxtx_ring, ptrs.producer); |
| ring->consumer = offsetof(struct xdp_rxtx_ring, ptrs.consumer); |
| ring->desc = offsetof(struct xdp_rxtx_ring, desc); |
| } |
| |
| static void xsk_enter_umem_offsets(struct xdp_ring_offset_v1 *ring) |
| { |
| ring->producer = offsetof(struct xdp_umem_ring, ptrs.producer); |
| ring->consumer = offsetof(struct xdp_umem_ring, ptrs.consumer); |
| ring->desc = offsetof(struct xdp_umem_ring, desc); |
| } |
| |
| static int xsk_getsockopt(struct socket *sock, int level, int optname, |
| char __user *optval, int __user *optlen) |
| { |
| struct sock *sk = sock->sk; |
| struct xdp_sock *xs = xdp_sk(sk); |
| int len; |
| |
| if (level != SOL_XDP) |
| return -ENOPROTOOPT; |
| |
| if (get_user(len, optlen)) |
| return -EFAULT; |
| if (len < 0) |
| return -EINVAL; |
| |
| switch (optname) { |
| case XDP_STATISTICS: |
| { |
| struct xdp_statistics stats; |
| |
| if (len < sizeof(stats)) |
| return -EINVAL; |
| |
| mutex_lock(&xs->mutex); |
| stats.rx_dropped = xs->rx_dropped; |
| stats.rx_invalid_descs = xskq_nb_invalid_descs(xs->rx); |
| stats.tx_invalid_descs = xskq_nb_invalid_descs(xs->tx); |
| mutex_unlock(&xs->mutex); |
| |
| if (copy_to_user(optval, &stats, sizeof(stats))) |
| return -EFAULT; |
| if (put_user(sizeof(stats), optlen)) |
| return -EFAULT; |
| |
| return 0; |
| } |
| case XDP_MMAP_OFFSETS: |
| { |
| struct xdp_mmap_offsets off; |
| struct xdp_mmap_offsets_v1 off_v1; |
| bool flags_supported = true; |
| void *to_copy; |
| |
| if (len < sizeof(off_v1)) |
| return -EINVAL; |
| else if (len < sizeof(off)) |
| flags_supported = false; |
| |
| if (flags_supported) { |
| /* xdp_ring_offset is identical to xdp_ring_offset_v1 |
| * except for the flags field added to the end. |
| */ |
| xsk_enter_rxtx_offsets((struct xdp_ring_offset_v1 *) |
| &off.rx); |
| xsk_enter_rxtx_offsets((struct xdp_ring_offset_v1 *) |
| &off.tx); |
| xsk_enter_umem_offsets((struct xdp_ring_offset_v1 *) |
| &off.fr); |
| xsk_enter_umem_offsets((struct xdp_ring_offset_v1 *) |
| &off.cr); |
| off.rx.flags = offsetof(struct xdp_rxtx_ring, |
| ptrs.flags); |
| off.tx.flags = offsetof(struct xdp_rxtx_ring, |
| ptrs.flags); |
| off.fr.flags = offsetof(struct xdp_umem_ring, |
| ptrs.flags); |
| off.cr.flags = offsetof(struct xdp_umem_ring, |
| ptrs.flags); |
| |
| len = sizeof(off); |
| to_copy = &off; |
| } else { |
| xsk_enter_rxtx_offsets(&off_v1.rx); |
| xsk_enter_rxtx_offsets(&off_v1.tx); |
| xsk_enter_umem_offsets(&off_v1.fr); |
| xsk_enter_umem_offsets(&off_v1.cr); |
| |
| len = sizeof(off_v1); |
| to_copy = &off_v1; |
| } |
| |
| if (copy_to_user(optval, to_copy, len)) |
| return -EFAULT; |
| if (put_user(len, optlen)) |
| return -EFAULT; |
| |
| return 0; |
| } |
| case XDP_OPTIONS: |
| { |
| struct xdp_options opts = {}; |
| |
| if (len < sizeof(opts)) |
| return -EINVAL; |
| |
| mutex_lock(&xs->mutex); |
| if (xs->zc) |
| opts.flags |= XDP_OPTIONS_ZEROCOPY; |
| mutex_unlock(&xs->mutex); |
| |
| len = sizeof(opts); |
| if (copy_to_user(optval, &opts, len)) |
| return -EFAULT; |
| if (put_user(len, optlen)) |
| return -EFAULT; |
| |
| return 0; |
| } |
| default: |
| break; |
| } |
| |
| return -EOPNOTSUPP; |
| } |
| |
| static int xsk_mmap(struct file *file, struct socket *sock, |
| struct vm_area_struct *vma) |
| { |
| loff_t offset = (loff_t)vma->vm_pgoff << PAGE_SHIFT; |
| unsigned long size = vma->vm_end - vma->vm_start; |
| struct xdp_sock *xs = xdp_sk(sock->sk); |
| struct xsk_queue *q = NULL; |
| struct xdp_umem *umem; |
| unsigned long pfn; |
| struct page *qpg; |
| |
| if (READ_ONCE(xs->state) != XSK_READY) |
| return -EBUSY; |
| |
| if (offset == XDP_PGOFF_RX_RING) { |
| q = READ_ONCE(xs->rx); |
| } else if (offset == XDP_PGOFF_TX_RING) { |
| q = READ_ONCE(xs->tx); |
| } else { |
| umem = READ_ONCE(xs->umem); |
| if (!umem) |
| return -EINVAL; |
| |
| /* Matches the smp_wmb() in XDP_UMEM_REG */ |
| smp_rmb(); |
| if (offset == XDP_UMEM_PGOFF_FILL_RING) |
| q = READ_ONCE(umem->fq); |
| else if (offset == XDP_UMEM_PGOFF_COMPLETION_RING) |
| q = READ_ONCE(umem->cq); |
| } |
| |
| if (!q) |
| return -EINVAL; |
| |
| /* Matches the smp_wmb() in xsk_init_queue */ |
| smp_rmb(); |
| qpg = virt_to_head_page(q->ring); |
| if (size > page_size(qpg)) |
| return -EINVAL; |
| |
| pfn = virt_to_phys(q->ring) >> PAGE_SHIFT; |
| return remap_pfn_range(vma, vma->vm_start, pfn, |
| size, vma->vm_page_prot); |
| } |
| |
| static int xsk_notifier(struct notifier_block *this, |
| unsigned long msg, void *ptr) |
| { |
| struct net_device *dev = netdev_notifier_info_to_dev(ptr); |
| struct net *net = dev_net(dev); |
| struct sock *sk; |
| |
| switch (msg) { |
| case NETDEV_UNREGISTER: |
| mutex_lock(&net->xdp.lock); |
| sk_for_each(sk, &net->xdp.list) { |
| struct xdp_sock *xs = xdp_sk(sk); |
| |
| mutex_lock(&xs->mutex); |
| if (xs->dev == dev) { |
| sk->sk_err = ENETDOWN; |
| if (!sock_flag(sk, SOCK_DEAD)) |
| sk->sk_error_report(sk); |
| |
| xsk_unbind_dev(xs); |
| |
| /* Clear device references in umem. */ |
| xdp_umem_clear_dev(xs->umem); |
| } |
| mutex_unlock(&xs->mutex); |
| } |
| mutex_unlock(&net->xdp.lock); |
| break; |
| } |
| return NOTIFY_DONE; |
| } |
| |
| static struct proto xsk_proto = { |
| .name = "XDP", |
| .owner = THIS_MODULE, |
| .obj_size = sizeof(struct xdp_sock), |
| }; |
| |
| static const struct proto_ops xsk_proto_ops = { |
| .family = PF_XDP, |
| .owner = THIS_MODULE, |
| .release = xsk_release, |
| .bind = xsk_bind, |
| .connect = sock_no_connect, |
| .socketpair = sock_no_socketpair, |
| .accept = sock_no_accept, |
| .getname = sock_no_getname, |
| .poll = xsk_poll, |
| .ioctl = sock_no_ioctl, |
| .listen = sock_no_listen, |
| .shutdown = sock_no_shutdown, |
| .setsockopt = xsk_setsockopt, |
| .getsockopt = xsk_getsockopt, |
| .sendmsg = xsk_sendmsg, |
| .recvmsg = sock_no_recvmsg, |
| .mmap = xsk_mmap, |
| .sendpage = sock_no_sendpage, |
| }; |
| |
| static void xsk_destruct(struct sock *sk) |
| { |
| struct xdp_sock *xs = xdp_sk(sk); |
| |
| if (!sock_flag(sk, SOCK_DEAD)) |
| return; |
| |
| xdp_put_umem(xs->umem); |
| |
| sk_refcnt_debug_dec(sk); |
| } |
| |
| static int xsk_create(struct net *net, struct socket *sock, int protocol, |
| int kern) |
| { |
| struct sock *sk; |
| struct xdp_sock *xs; |
| |
| if (!ns_capable(net->user_ns, CAP_NET_RAW)) |
| return -EPERM; |
| if (sock->type != SOCK_RAW) |
| return -ESOCKTNOSUPPORT; |
| |
| if (protocol) |
| return -EPROTONOSUPPORT; |
| |
| sock->state = SS_UNCONNECTED; |
| |
| sk = sk_alloc(net, PF_XDP, GFP_KERNEL, &xsk_proto, kern); |
| if (!sk) |
| return -ENOBUFS; |
| |
| sock->ops = &xsk_proto_ops; |
| |
| sock_init_data(sock, sk); |
| |
| sk->sk_family = PF_XDP; |
| |
| sk->sk_destruct = xsk_destruct; |
| sk_refcnt_debug_inc(sk); |
| |
| sock_set_flag(sk, SOCK_RCU_FREE); |
| |
| xs = xdp_sk(sk); |
| xs->state = XSK_READY; |
| mutex_init(&xs->mutex); |
| spin_lock_init(&xs->rx_lock); |
| spin_lock_init(&xs->tx_completion_lock); |
| |
| INIT_LIST_HEAD(&xs->map_list); |
| spin_lock_init(&xs->map_list_lock); |
| |
| mutex_lock(&net->xdp.lock); |
| sk_add_node_rcu(sk, &net->xdp.list); |
| mutex_unlock(&net->xdp.lock); |
| |
| local_bh_disable(); |
| sock_prot_inuse_add(net, &xsk_proto, 1); |
| local_bh_enable(); |
| |
| return 0; |
| } |
| |
| static const struct net_proto_family xsk_family_ops = { |
| .family = PF_XDP, |
| .create = xsk_create, |
| .owner = THIS_MODULE, |
| }; |
| |
| static struct notifier_block xsk_netdev_notifier = { |
| .notifier_call = xsk_notifier, |
| }; |
| |
| static int __net_init xsk_net_init(struct net *net) |
| { |
| mutex_init(&net->xdp.lock); |
| INIT_HLIST_HEAD(&net->xdp.list); |
| return 0; |
| } |
| |
| static void __net_exit xsk_net_exit(struct net *net) |
| { |
| WARN_ON_ONCE(!hlist_empty(&net->xdp.list)); |
| } |
| |
| static struct pernet_operations xsk_net_ops = { |
| .init = xsk_net_init, |
| .exit = xsk_net_exit, |
| }; |
| |
| static int __init xsk_init(void) |
| { |
| int err, cpu; |
| |
| err = proto_register(&xsk_proto, 0 /* no slab */); |
| if (err) |
| goto out; |
| |
| err = sock_register(&xsk_family_ops); |
| if (err) |
| goto out_proto; |
| |
| err = register_pernet_subsys(&xsk_net_ops); |
| if (err) |
| goto out_sk; |
| |
| err = register_netdevice_notifier(&xsk_netdev_notifier); |
| if (err) |
| goto out_pernet; |
| |
| for_each_possible_cpu(cpu) |
| INIT_LIST_HEAD(&per_cpu(xskmap_flush_list, cpu)); |
| return 0; |
| |
| out_pernet: |
| unregister_pernet_subsys(&xsk_net_ops); |
| out_sk: |
| sock_unregister(PF_XDP); |
| out_proto: |
| proto_unregister(&xsk_proto); |
| out: |
| return err; |
| } |
| |
| fs_initcall(xsk_init); |