From: =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= <bjorn.topel@intel.com>
Date: Wed, 20 May 2020 21:20:50 +0200
Subject: xsk: Move xskmap.c to net/xdp/
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Patch-mainline: v5.8-rc1
Git-commit: d20a1676df7e4c3c23d73299159811a50e4854bc
References: bsc#1176447
The XSKMAP is partly implemented by net/xdp/xsk.c. Move xskmap.c from
kernel/bpf/ to net/xdp/, which is the logical place for AF_XDP related
code. Also, move AF_XDP struct definitions, and function declarations
only used by AF_XDP internals into net/xdp/xsk.h.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200520192103.355233-3-bjorn.topel@gmail.com
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
include/net/xdp_sock.h | 20 ---
kernel/bpf/Makefile | 3
kernel/bpf/xskmap.c | 265 ------------------------------------------------
net/xdp/Makefile | 2
net/xdp/xsk.h | 16 ++
net/xdp/xskmap.c | 267 +++++++++++++++++++++++++++++++++++++++++++++++++
6 files changed, 284 insertions(+), 289 deletions(-)
rename {kernel/bpf => net/xdp}/xskmap.c (99%)
--- a/include/net/xdp_sock.h
+++ b/include/net/xdp_sock.h
@@ -65,22 +65,12 @@ struct xdp_umem {
struct list_head xsk_tx_list;
};
-/* Nodes are linked in the struct xdp_sock map_list field, and used to
- * track which maps a certain socket reside in.
- */
-
struct xsk_map {
struct bpf_map map;
spinlock_t lock; /* Synchronize map updates */
struct xdp_sock *xsk_map[];
};
-struct xsk_map_node {
- struct list_head node;
- struct xsk_map *map;
- struct xdp_sock **map_entry;
-};
-
struct xdp_sock {
/* struct sock must be the first member of struct xdp_sock */
struct sock sk;
@@ -114,7 +104,6 @@ struct xdp_sock {
struct xdp_buff;
#ifdef CONFIG_XDP_SOCKETS
int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp);
-bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs);
/* Used from netdev driver */
bool xsk_umem_has_addrs(struct xdp_umem *umem, u32 cnt);
bool xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr);
@@ -133,10 +122,6 @@ void xsk_clear_rx_need_wakeup(struct xdp
void xsk_clear_tx_need_wakeup(struct xdp_umem *umem);
bool xsk_umem_uses_need_wakeup(struct xdp_umem *umem);
-void xsk_map_try_sock_delete(struct xsk_map *map, struct xdp_sock *xs,
- struct xdp_sock **map_entry);
-int xsk_map_inc(struct xsk_map *map);
-void xsk_map_put(struct xsk_map *map);
int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp);
void __xsk_map_flush(void);
@@ -248,11 +233,6 @@ static inline int xsk_generic_rcv(struct
return -ENOTSUPP;
}
-static inline bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs)
-{
- return false;
-}
-
static inline bool xsk_umem_has_addrs(struct xdp_umem *umem, u32 cnt)
{
return false;
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -11,9 +11,6 @@ obj-$(CONFIG_BPF_SYSCALL) += btf.o
ifeq ($(CONFIG_NET),y)
obj-$(CONFIG_BPF_SYSCALL) += devmap.o
obj-$(CONFIG_BPF_SYSCALL) += cpumap.o
-ifeq ($(CONFIG_XDP_SOCKETS),y)
-obj-$(CONFIG_BPF_SYSCALL) += xskmap.o
-endif
obj-$(CONFIG_BPF_SYSCALL) += offload.o
endif
ifeq ($(CONFIG_PERF_EVENTS),y)
--- a/kernel/bpf/xskmap.c
+++ /dev/null
@@ -1,265 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/* XSKMAP used for AF_XDP sockets
- * Copyright(c) 2018 Intel Corporation.
- */
-
-#include <linux/bpf.h>
-#include <linux/capability.h>
-#include <net/xdp_sock.h>
-#include <linux/slab.h>
-#include <linux/sched.h>
-
-int xsk_map_inc(struct xsk_map *map)
-{
- bpf_map_inc(&map->map);
- return 0;
-}
-
-void xsk_map_put(struct xsk_map *map)
-{
- bpf_map_put(&map->map);
-}
-
-static struct xsk_map_node *xsk_map_node_alloc(struct xsk_map *map,
- struct xdp_sock **map_entry)
-{
- struct xsk_map_node *node;
- int err;
-
- node = kzalloc(sizeof(*node), GFP_ATOMIC | __GFP_NOWARN);
- if (!node)
- return ERR_PTR(-ENOMEM);
-
- err = xsk_map_inc(map);
- if (err) {
- kfree(node);
- return ERR_PTR(err);
- }
-
- node->map = map;
- node->map_entry = map_entry;
- return node;
-}
-
-static void xsk_map_node_free(struct xsk_map_node *node)
-{
- xsk_map_put(node->map);
- kfree(node);
-}
-
-static void xsk_map_sock_add(struct xdp_sock *xs, struct xsk_map_node *node)
-{
- spin_lock_bh(&xs->map_list_lock);
- list_add_tail(&node->node, &xs->map_list);
- spin_unlock_bh(&xs->map_list_lock);
-}
-
-static void xsk_map_sock_delete(struct xdp_sock *xs,
- struct xdp_sock **map_entry)
-{
- struct xsk_map_node *n, *tmp;
-
- spin_lock_bh(&xs->map_list_lock);
- list_for_each_entry_safe(n, tmp, &xs->map_list, node) {
- if (map_entry == n->map_entry) {
- list_del(&n->node);
- xsk_map_node_free(n);
- }
- }
- spin_unlock_bh(&xs->map_list_lock);
-}
-
-static struct bpf_map *xsk_map_alloc(union bpf_attr *attr)
-{
- struct bpf_map_memory mem;
- int err, numa_node;
- struct xsk_map *m;
- u64 size;
-
- 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);
-
- numa_node = bpf_map_attr_numa_node(attr);
- size = struct_size(m, xsk_map, attr->max_entries);
-
- err = bpf_map_charge_init(&mem, size);
- if (err < 0)
- return ERR_PTR(err);
-
- m = bpf_map_area_alloc(size, numa_node);
- if (!m) {
- bpf_map_charge_finish(&mem);
- return ERR_PTR(-ENOMEM);
- }
-
- bpf_map_init_from_attr(&m->map, attr);
- bpf_map_charge_move(&m->map.memory, &mem);
- spin_lock_init(&m->lock);
-
- return &m->map;
-}
-
-static void xsk_map_free(struct bpf_map *map)
-{
- struct xsk_map *m = container_of(map, struct xsk_map, map);
-
- bpf_clear_redirect_map(map);
- synchronize_net();
- bpf_map_area_free(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;
-}
-
-static u32 xsk_map_gen_lookup(struct bpf_map *map, struct bpf_insn *insn_buf)
-{
- const int ret = BPF_REG_0, mp = BPF_REG_1, index = BPF_REG_2;
- struct bpf_insn *insn = insn_buf;
-
- *insn++ = BPF_LDX_MEM(BPF_W, ret, index, 0);
- *insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 5);
- *insn++ = BPF_ALU64_IMM(BPF_LSH, ret, ilog2(sizeof(struct xsk_sock *)));
- *insn++ = BPF_ALU64_IMM(BPF_ADD, mp, offsetof(struct xsk_map, xsk_map));
- *insn++ = BPF_ALU64_REG(BPF_ADD, ret, mp);
- *insn++ = BPF_LDX_MEM(BPF_SIZEOF(struct xsk_sock *), ret, ret, 0);
- *insn++ = BPF_JMP_IMM(BPF_JA, 0, 0, 1);
- *insn++ = BPF_MOV64_IMM(ret, 0);
- return insn - insn_buf;
-}
-
-static void *xsk_map_lookup_elem(struct bpf_map *map, void *key)
-{
- WARN_ON_ONCE(!rcu_read_lock_held());
- return __xsk_map_lookup_elem(map, *(u32 *)key);
-}
-
-static void *xsk_map_lookup_elem_sys_only(struct bpf_map *map, void *key)
-{
- return ERR_PTR(-EOPNOTSUPP);
-}
-
-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);
- struct xdp_sock *xs, *old_xs, **map_entry;
- u32 i = *(u32 *)key, fd = *(u32 *)value;
- struct xsk_map_node *node;
- struct socket *sock;
- int err;
-
- if (unlikely(map_flags > BPF_EXIST))
- return -EINVAL;
- if (unlikely(i >= m->map.max_entries))
- return -E2BIG;
-
- 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;
- }
-
- map_entry = &m->xsk_map[i];
- node = xsk_map_node_alloc(m, map_entry);
- if (IS_ERR(node)) {
- sockfd_put(sock);
- return PTR_ERR(node);
- }
-
- spin_lock_bh(&m->lock);
- old_xs = READ_ONCE(*map_entry);
- if (old_xs == xs) {
- err = 0;
- goto out;
- } else if (old_xs && map_flags == BPF_NOEXIST) {
- err = -EEXIST;
- goto out;
- } else if (!old_xs && map_flags == BPF_EXIST) {
- err = -ENOENT;
- goto out;
- }
- xsk_map_sock_add(xs, node);
- WRITE_ONCE(*map_entry, xs);
- if (old_xs)
- xsk_map_sock_delete(old_xs, map_entry);
- spin_unlock_bh(&m->lock);
- sockfd_put(sock);
- return 0;
-
-out:
- spin_unlock_bh(&m->lock);
- sockfd_put(sock);
- xsk_map_node_free(node);
- return err;
-}
-
-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, **map_entry;
- int k = *(u32 *)key;
-
- if (k >= map->max_entries)
- return -EINVAL;
-
- spin_lock_bh(&m->lock);
- map_entry = &m->xsk_map[k];
- old_xs = xchg(map_entry, NULL);
- if (old_xs)
- xsk_map_sock_delete(old_xs, map_entry);
- spin_unlock_bh(&m->lock);
-
- return 0;
-}
-
-void xsk_map_try_sock_delete(struct xsk_map *map, struct xdp_sock *xs,
- struct xdp_sock **map_entry)
-{
- spin_lock_bh(&map->lock);
- if (READ_ONCE(*map_entry) == xs) {
- WRITE_ONCE(*map_entry, NULL);
- xsk_map_sock_delete(xs, map_entry);
- }
- spin_unlock_bh(&map->lock);
-}
-
-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_gen_lookup = xsk_map_gen_lookup,
- .map_lookup_elem_sys_only = xsk_map_lookup_elem_sys_only,
- .map_update_elem = xsk_map_update_elem,
- .map_delete_elem = xsk_map_delete_elem,
- .map_check_btf = map_check_no_btf,
-};
--- a/net/xdp/Makefile
+++ b/net/xdp/Makefile
@@ -1,3 +1,3 @@
# SPDX-License-Identifier: GPL-2.0-only
-obj-$(CONFIG_XDP_SOCKETS) += xsk.o xdp_umem.o xsk_queue.o
+obj-$(CONFIG_XDP_SOCKETS) += xsk.o xdp_umem.o xsk_queue.o xskmap.o
obj-$(CONFIG_XDP_SOCKETS_DIAG) += xsk_diag.o
--- a/net/xdp/xsk.h
+++ b/net/xdp/xsk.h
@@ -17,9 +17,25 @@ struct xdp_mmap_offsets_v1 {
struct xdp_ring_offset_v1 cr;
};
+/* Nodes are linked in the struct xdp_sock map_list field, and used to
+ * track which maps a certain socket reside in.
+ */
+
+struct xsk_map_node {
+ struct list_head node;
+ struct xsk_map *map;
+ struct xdp_sock **map_entry;
+};
+
static inline struct xdp_sock *xdp_sk(struct sock *sk)
{
return (struct xdp_sock *)sk;
}
+bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs);
+void xsk_map_try_sock_delete(struct xsk_map *map, struct xdp_sock *xs,
+ struct xdp_sock **map_entry);
+int xsk_map_inc(struct xsk_map *map);
+void xsk_map_put(struct xsk_map *map);
+
#endif /* XSK_H_ */
--- /dev/null
+++ b/net/xdp/xskmap.c
@@ -0,0 +1,267 @@
+// SPDX-License-Identifier: GPL-2.0
+/* XSKMAP used for AF_XDP sockets
+ * Copyright(c) 2018 Intel Corporation.
+ */
+
+#include <linux/bpf.h>
+#include <linux/capability.h>
+#include <net/xdp_sock.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+
+#include "xsk.h"
+
+int xsk_map_inc(struct xsk_map *map)
+{
+ bpf_map_inc(&map->map);
+ return 0;
+}
+
+void xsk_map_put(struct xsk_map *map)
+{
+ bpf_map_put(&map->map);
+}
+
+static struct xsk_map_node *xsk_map_node_alloc(struct xsk_map *map,
+ struct xdp_sock **map_entry)
+{
+ struct xsk_map_node *node;
+ int err;
+
+ node = kzalloc(sizeof(*node), GFP_ATOMIC | __GFP_NOWARN);
+ if (!node)
+ return ERR_PTR(-ENOMEM);
+
+ err = xsk_map_inc(map);
+ if (err) {
+ kfree(node);
+ return ERR_PTR(err);
+ }
+
+ node->map = map;
+ node->map_entry = map_entry;
+ return node;
+}
+
+static void xsk_map_node_free(struct xsk_map_node *node)
+{
+ xsk_map_put(node->map);
+ kfree(node);
+}
+
+static void xsk_map_sock_add(struct xdp_sock *xs, struct xsk_map_node *node)
+{
+ spin_lock_bh(&xs->map_list_lock);
+ list_add_tail(&node->node, &xs->map_list);
+ spin_unlock_bh(&xs->map_list_lock);
+}
+
+static void xsk_map_sock_delete(struct xdp_sock *xs,
+ struct xdp_sock **map_entry)
+{
+ struct xsk_map_node *n, *tmp;
+
+ spin_lock_bh(&xs->map_list_lock);
+ list_for_each_entry_safe(n, tmp, &xs->map_list, node) {
+ if (map_entry == n->map_entry) {
+ list_del(&n->node);
+ xsk_map_node_free(n);
+ }
+ }
+ spin_unlock_bh(&xs->map_list_lock);
+}
+
+static struct bpf_map *xsk_map_alloc(union bpf_attr *attr)
+{
+ struct bpf_map_memory mem;
+ int err, numa_node;
+ struct xsk_map *m;
+ u64 size;
+
+ 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);
+
+ numa_node = bpf_map_attr_numa_node(attr);
+ size = struct_size(m, xsk_map, attr->max_entries);
+
+ err = bpf_map_charge_init(&mem, size);
+ if (err < 0)
+ return ERR_PTR(err);
+
+ m = bpf_map_area_alloc(size, numa_node);
+ if (!m) {
+ bpf_map_charge_finish(&mem);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ bpf_map_init_from_attr(&m->map, attr);
+ bpf_map_charge_move(&m->map.memory, &mem);
+ spin_lock_init(&m->lock);
+
+ return &m->map;
+}
+
+static void xsk_map_free(struct bpf_map *map)
+{
+ struct xsk_map *m = container_of(map, struct xsk_map, map);
+
+ bpf_clear_redirect_map(map);
+ synchronize_net();
+ bpf_map_area_free(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;
+}
+
+static u32 xsk_map_gen_lookup(struct bpf_map *map, struct bpf_insn *insn_buf)
+{
+ const int ret = BPF_REG_0, mp = BPF_REG_1, index = BPF_REG_2;
+ struct bpf_insn *insn = insn_buf;
+
+ *insn++ = BPF_LDX_MEM(BPF_W, ret, index, 0);
+ *insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 5);
+ *insn++ = BPF_ALU64_IMM(BPF_LSH, ret, ilog2(sizeof(struct xsk_sock *)));
+ *insn++ = BPF_ALU64_IMM(BPF_ADD, mp, offsetof(struct xsk_map, xsk_map));
+ *insn++ = BPF_ALU64_REG(BPF_ADD, ret, mp);
+ *insn++ = BPF_LDX_MEM(BPF_SIZEOF(struct xsk_sock *), ret, ret, 0);
+ *insn++ = BPF_JMP_IMM(BPF_JA, 0, 0, 1);
+ *insn++ = BPF_MOV64_IMM(ret, 0);
+ return insn - insn_buf;
+}
+
+static void *xsk_map_lookup_elem(struct bpf_map *map, void *key)
+{
+ WARN_ON_ONCE(!rcu_read_lock_held());
+ return __xsk_map_lookup_elem(map, *(u32 *)key);
+}
+
+static void *xsk_map_lookup_elem_sys_only(struct bpf_map *map, void *key)
+{
+ return ERR_PTR(-EOPNOTSUPP);
+}
+
+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);
+ struct xdp_sock *xs, *old_xs, **map_entry;
+ u32 i = *(u32 *)key, fd = *(u32 *)value;
+ struct xsk_map_node *node;
+ struct socket *sock;
+ int err;
+
+ if (unlikely(map_flags > BPF_EXIST))
+ return -EINVAL;
+ if (unlikely(i >= m->map.max_entries))
+ return -E2BIG;
+
+ 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;
+ }
+
+ map_entry = &m->xsk_map[i];
+ node = xsk_map_node_alloc(m, map_entry);
+ if (IS_ERR(node)) {
+ sockfd_put(sock);
+ return PTR_ERR(node);
+ }
+
+ spin_lock_bh(&m->lock);
+ old_xs = READ_ONCE(*map_entry);
+ if (old_xs == xs) {
+ err = 0;
+ goto out;
+ } else if (old_xs && map_flags == BPF_NOEXIST) {
+ err = -EEXIST;
+ goto out;
+ } else if (!old_xs && map_flags == BPF_EXIST) {
+ err = -ENOENT;
+ goto out;
+ }
+ xsk_map_sock_add(xs, node);
+ WRITE_ONCE(*map_entry, xs);
+ if (old_xs)
+ xsk_map_sock_delete(old_xs, map_entry);
+ spin_unlock_bh(&m->lock);
+ sockfd_put(sock);
+ return 0;
+
+out:
+ spin_unlock_bh(&m->lock);
+ sockfd_put(sock);
+ xsk_map_node_free(node);
+ return err;
+}
+
+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, **map_entry;
+ int k = *(u32 *)key;
+
+ if (k >= map->max_entries)
+ return -EINVAL;
+
+ spin_lock_bh(&m->lock);
+ map_entry = &m->xsk_map[k];
+ old_xs = xchg(map_entry, NULL);
+ if (old_xs)
+ xsk_map_sock_delete(old_xs, map_entry);
+ spin_unlock_bh(&m->lock);
+
+ return 0;
+}
+
+void xsk_map_try_sock_delete(struct xsk_map *map, struct xdp_sock *xs,
+ struct xdp_sock **map_entry)
+{
+ spin_lock_bh(&map->lock);
+ if (READ_ONCE(*map_entry) == xs) {
+ WRITE_ONCE(*map_entry, NULL);
+ xsk_map_sock_delete(xs, map_entry);
+ }
+ spin_unlock_bh(&map->lock);
+}
+
+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_gen_lookup = xsk_map_gen_lookup,
+ .map_lookup_elem_sys_only = xsk_map_lookup_elem_sys_only,
+ .map_update_elem = xsk_map_update_elem,
+ .map_delete_elem = xsk_map_delete_elem,
+ .map_check_btf = map_check_no_btf,
+};