Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Minor conflict, a CHECK was placed into an if() statement
in net-next, whilst a newline was added to that CHECK
call in 'net'.  Thanks to Daniel for the merge resolution.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 241 insertions, 0 deletions

diff --git a/kernel/bpf/xskmap.c b/kernel/bpf/xskmap.c
new file mode 100644
index 000000000000..cb3a12137404
--- /dev/null
+++ b/kernel/bpf/xskmap.c
@@ -0,0 +1,241 @@
+// SPDX-License-Identifier: GPL-2.0
+/* XSKMAP used for AF_XDP sockets
+ * Copyright(c) 2018 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/bpf.h>
+#include <linux/capability.h>
+#include <net/xdp_sock.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+
+struct xsk_map {
+        struct bpf_map map;
+        struct xdp_sock **xsk_map;
+        struct list_head __percpu *flush_list;
+};
+
+static struct bpf_map *xsk_map_alloc(union bpf_attr *attr)
+{
+        int cpu, err = -EINVAL;
+        struct xsk_map *m;
+        u64 cost;
+
+        if (!capable(CAP_NET_ADMIN))
+                return ERR_PTR(-EPERM);
+
+        if (attr->max_entries == 0 || attr->key_size != 4 ||
+            attr->value_size != 4 ||
+            attr->map_flags & ~(BPF_F_NUMA_NODE | BPF_F_RDONLY | BPF_F_WRONLY))
+                return ERR_PTR(-EINVAL);
+
+        m = kzalloc(sizeof(*m), GFP_USER);
+        if (!m)
+                return ERR_PTR(-ENOMEM);
+
+        bpf_map_init_from_attr(&m->map, attr);
+
+        cost = (u64)m->map.max_entries * sizeof(struct xdp_sock *);
+        cost += sizeof(struct list_head) * num_possible_cpus();
+        if (cost >= U32_MAX - PAGE_SIZE)
+                goto free_m;
+
+        m->map.pages = round_up(cost, PAGE_SIZE) >> PAGE_SHIFT;
+
+        /* Notice returns -EPERM on if map size is larger than memlock limit */
+        err = bpf_map_precharge_memlock(m->map.pages);
+        if (err)
+                goto free_m;
+
+        err = -ENOMEM;
+
+        m->flush_list = alloc_percpu(struct list_head);
+        if (!m->flush_list)
+                goto free_m;
+
+        for_each_possible_cpu(cpu)
+                INIT_LIST_HEAD(per_cpu_ptr(m->flush_list, cpu));
+
+        m->xsk_map = bpf_map_area_alloc(m->map.max_entries *
+                                        sizeof(struct xdp_sock *),
+                                        m->map.numa_node);
+        if (!m->xsk_map)
+                goto free_percpu;
+        return &m->map;
+
+free_percpu:
+        free_percpu(m->flush_list);
+free_m:
+        kfree(m);
+        return ERR_PTR(err);
+}
+
+static void xsk_map_free(struct bpf_map *map)
+{
+        struct xsk_map *m = container_of(map, struct xsk_map, map);
+        int i;
+
+        synchronize_net();
+
+        for (i = 0; i < map->max_entries; i++) {
+                struct xdp_sock *xs;
+
+                xs = m->xsk_map[i];
+                if (!xs)
+                        continue;
+
+                sock_put((struct sock *)xs);
+        }
+
+        free_percpu(m->flush_list);
+        bpf_map_area_free(m->xsk_map);
+        kfree(m);
+}
+
+static int xsk_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
+{
+        struct xsk_map *m = container_of(map, struct xsk_map, map);
+        u32 index = key ? *(u32 *)key : U32_MAX;
+        u32 *next = next_key;
+
+        if (index >= m->map.max_entries) {
+                *next = 0;
+                return 0;
+        }
+
+        if (index == m->map.max_entries - 1)
+                return -ENOENT;
+        *next = index + 1;
+        return 0;
+}
+
+struct xdp_sock *__xsk_map_lookup_elem(struct bpf_map *map, u32 key)
+{
+        struct xsk_map *m = container_of(map, struct xsk_map, map);
+        struct xdp_sock *xs;
+
+        if (key >= map->max_entries)
+                return NULL;
+
+        xs = READ_ONCE(m->xsk_map[key]);
+        return xs;
+}
+
+int __xsk_map_redirect(struct bpf_map *map, struct xdp_buff *xdp,
+                       struct xdp_sock *xs)
+{
+        struct xsk_map *m = container_of(map, struct xsk_map, map);
+        struct list_head *flush_list = this_cpu_ptr(m->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(struct bpf_map *map)
+{
+        struct xsk_map *m = container_of(map, struct xsk_map, map);
+        struct list_head *flush_list = this_cpu_ptr(m->flush_list);
+        struct xdp_sock *xs, *tmp;
+
+        list_for_each_entry_safe(xs, tmp, flush_list, flush_node) {
+                xsk_flush(xs);
+                __list_del(xs->flush_node.prev, xs->flush_node.next);
+                xs->flush_node.prev = NULL;
+        }
+}
+
+static void *xsk_map_lookup_elem(struct bpf_map *map, void *key)
+{
+        return NULL;
+}
+
+static int xsk_map_update_elem(struct bpf_map *map, void *key, void *value,
+                               u64 map_flags)
+{
+        struct xsk_map *m = container_of(map, struct xsk_map, map);
+        u32 i = *(u32 *)key, fd = *(u32 *)value;
+        struct xdp_sock *xs, *old_xs;
+        struct socket *sock;
+        int err;
+
+        if (unlikely(map_flags > BPF_EXIST))
+                return -EINVAL;
+        if (unlikely(i >= m->map.max_entries))
+                return -E2BIG;
+        if (unlikely(map_flags == BPF_NOEXIST))
+                return -EEXIST;
+
+        sock = sockfd_lookup(fd, &err);
+        if (!sock)
+                return err;
+
+        if (sock->sk->sk_family != PF_XDP) {
+                sockfd_put(sock);
+                return -EOPNOTSUPP;
+        }
+
+        xs = (struct xdp_sock *)sock->sk;
+
+        if (!xsk_is_setup_for_bpf_map(xs)) {
+                sockfd_put(sock);
+                return -EOPNOTSUPP;
+        }
+
+        sock_hold(sock->sk);
+
+        old_xs = xchg(&m->xsk_map[i], xs);
+        if (old_xs) {
+                /* Make sure we've flushed everything. */
+                synchronize_net();
+                sock_put((struct sock *)old_xs);
+        }
+
+        sockfd_put(sock);
+        return 0;
+}
+
+static int xsk_map_delete_elem(struct bpf_map *map, void *key)
+{
+        struct xsk_map *m = container_of(map, struct xsk_map, map);
+        struct xdp_sock *old_xs;
+        int k = *(u32 *)key;
+
+        if (k >= map->max_entries)
+                return -EINVAL;
+
+        old_xs = xchg(&m->xsk_map[k], NULL);
+        if (old_xs) {
+                /* Make sure we've flushed everything. */
+                synchronize_net();
+                sock_put((struct sock *)old_xs);
+        }
+
+        return 0;
+}
+
+const struct bpf_map_ops xsk_map_ops = {
+        .map_alloc = xsk_map_alloc,
+        .map_free = xsk_map_free,
+        .map_get_next_key = xsk_map_get_next_key,
+        .map_lookup_elem = xsk_map_lookup_elem,
+        .map_update_elem = xsk_map_update_elem,
+        .map_delete_elem = xsk_map_delete_elem,
+};
+
+