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authorDaniel Borkmann2021-03-10 01:06:34 +0100
committerDaniel Borkmann2021-03-10 01:07:21 +0100
commit32f91529e2bdbe0d92edb3ced41dfba4beffa84a (patch)
tree2e6ca2aa0d6d1ac694002dd4aff11915473d4118
parent11d39cfeecfc9d92a5faa2a55c228e796478e0cb (diff)
parentee75aef23afe6e88497151c127c13ed69f41aaa2 (diff)
Merge branch 'bpf-xdp-redirect'
Björn Töpel says: ==================== This two patch series contain two optimizations for the bpf_redirect_map() helper and the xdp_do_redirect() function. The bpf_redirect_map() optimization is about avoiding the map lookup dispatching. Instead of having a switch-statement and selecting the correct lookup function, we let bpf_redirect_map() be a map operation, where each map has its own bpf_redirect_map() implementation. This way the run-time lookup is avoided. The xdp_do_redirect() patch restructures the code, so that the map pointer indirection can be avoided. Performance-wise I got 4% improvement for XSKMAP (sample:xdpsock/rx-drop), and 8% (sample:xdp_redirect_map) on my machine. v5->v6: Removed REDIR enum, and instead use map_id and map_type. (Daniel) Applied Daniel's fixups on patch 1. (Daniel) v4->v5: Renamed map operation to map_redirect. (Daniel) v3->v4: Made bpf_redirect_map() a map operation. (Daniel) v2->v3: Fix build when CONFIG_NET is not set. (lkp) v1->v2: Removed warning when CONFIG_BPF_SYSCALL was not set. (lkp) Cleaned up case-clause in xdp_do_generic_redirect_map(). (Toke) Re-added comment. (Toke) rfc->v1: Use map_id, and remove bpf_clear_redirect_map(). (Toke) Get rid of the macro and use __always_inline. (Jesper) ==================== Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
-rw-r--r--include/linux/bpf.h26
-rw-r--r--include/linux/filter.h31
-rw-r--r--include/net/xdp_sock.h19
-rw-r--r--include/trace/events/xdp.h62
-rw-r--r--kernel/bpf/cpumap.c9
-rw-r--r--kernel/bpf/devmap.c17
-rw-r--r--kernel/bpf/verifier.c13
-rw-r--r--net/core/filter.c209
-rw-r--r--net/xdp/xskmap.c17
9 files changed, 195 insertions, 208 deletions
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index c931bc97019d..a25730eaa148 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -118,6 +118,9 @@ struct bpf_map_ops {
void *owner, u32 size);
struct bpf_local_storage __rcu ** (*map_owner_storage_ptr)(void *owner);
+ /* Misc helpers.*/
+ int (*map_redirect)(struct bpf_map *map, u32 ifindex, u64 flags);
+
/* map_meta_equal must be implemented for maps that can be
* used as an inner map. It is a runtime check to ensure
* an inner map can be inserted to an outer map.
@@ -1450,9 +1453,9 @@ struct btf *bpf_get_btf_vmlinux(void);
/* Map specifics */
struct xdp_buff;
struct sk_buff;
+struct bpf_dtab_netdev;
+struct bpf_cpu_map_entry;
-struct bpf_dtab_netdev *__dev_map_lookup_elem(struct bpf_map *map, u32 key);
-struct bpf_dtab_netdev *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key);
void __dev_flush(void);
int dev_xdp_enqueue(struct net_device *dev, struct xdp_buff *xdp,
struct net_device *dev_rx);
@@ -1462,7 +1465,6 @@ int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, struct sk_buff *skb,
struct bpf_prog *xdp_prog);
bool dev_map_can_have_prog(struct bpf_map *map);
-struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key);
void __cpu_map_flush(void);
int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu, struct xdp_buff *xdp,
struct net_device *dev_rx);
@@ -1593,17 +1595,6 @@ static inline int bpf_obj_get_user(const char __user *pathname, int flags)
return -EOPNOTSUPP;
}
-static inline struct net_device *__dev_map_lookup_elem(struct bpf_map *map,
- u32 key)
-{
- return NULL;
-}
-
-static inline struct net_device *__dev_map_hash_lookup_elem(struct bpf_map *map,
- u32 key)
-{
- return NULL;
-}
static inline bool dev_map_can_have_prog(struct bpf_map *map)
{
return false;
@@ -1615,6 +1606,7 @@ static inline void __dev_flush(void)
struct xdp_buff;
struct bpf_dtab_netdev;
+struct bpf_cpu_map_entry;
static inline
int dev_xdp_enqueue(struct net_device *dev, struct xdp_buff *xdp,
@@ -1639,12 +1631,6 @@ static inline int dev_map_generic_redirect(struct bpf_dtab_netdev *dst,
return 0;
}
-static inline
-struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key)
-{
- return NULL;
-}
-
static inline void __cpu_map_flush(void)
{
}
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 3b00fc906ccd..b2b85b2cad8e 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -646,7 +646,8 @@ struct bpf_redirect_info {
u32 flags;
u32 tgt_index;
void *tgt_value;
- struct bpf_map *map;
+ u32 map_id;
+ enum bpf_map_type map_type;
u32 kern_flags;
struct bpf_nh_params nh;
};
@@ -1472,4 +1473,32 @@ static inline bool bpf_sk_lookup_run_v6(struct net *net, int protocol,
}
#endif /* IS_ENABLED(CONFIG_IPV6) */
+static __always_inline int __bpf_xdp_redirect_map(struct bpf_map *map, u32 ifindex, u64 flags,
+ void *lookup_elem(struct bpf_map *map, u32 key))
+{
+ struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
+
+ /* Lower bits of the flags are used as return code on lookup failure */
+ if (unlikely(flags > XDP_TX))
+ return XDP_ABORTED;
+
+ ri->tgt_value = lookup_elem(map, ifindex);
+ if (unlikely(!ri->tgt_value)) {
+ /* If the lookup fails we want to clear out the state in the
+ * redirect_info struct completely, so that if an eBPF program
+ * performs multiple lookups, the last one always takes
+ * precedence.
+ */
+ ri->map_id = INT_MAX; /* Valid map id idr range: [1,INT_MAX[ */
+ ri->map_type = BPF_MAP_TYPE_UNSPEC;
+ return flags;
+ }
+
+ ri->tgt_index = ifindex;
+ ri->map_id = map->id;
+ ri->map_type = map->map_type;
+
+ return XDP_REDIRECT;
+}
+
#endif /* __LINUX_FILTER_H__ */
diff --git a/include/net/xdp_sock.h b/include/net/xdp_sock.h
index cc17bc957548..9c0722c6d7ac 100644
--- a/include/net/xdp_sock.h
+++ b/include/net/xdp_sock.h
@@ -80,19 +80,6 @@ int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp);
int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp);
void __xsk_map_flush(void);
-static inline 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;
-}
-
#else
static inline int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
@@ -109,12 +96,6 @@ static inline void __xsk_map_flush(void)
{
}
-static inline struct xdp_sock *__xsk_map_lookup_elem(struct bpf_map *map,
- u32 key)
-{
- return NULL;
-}
-
#endif /* CONFIG_XDP_SOCKETS */
#endif /* _LINUX_XDP_SOCK_H */
diff --git a/include/trace/events/xdp.h b/include/trace/events/xdp.h
index 76a97176ab81..fcad3645a70b 100644
--- a/include/trace/events/xdp.h
+++ b/include/trace/events/xdp.h
@@ -86,19 +86,15 @@ struct _bpf_dtab_netdev {
};
#endif /* __DEVMAP_OBJ_TYPE */
-#define devmap_ifindex(tgt, map) \
- (((map->map_type == BPF_MAP_TYPE_DEVMAP || \
- map->map_type == BPF_MAP_TYPE_DEVMAP_HASH)) ? \
- ((struct _bpf_dtab_netdev *)tgt)->dev->ifindex : 0)
-
DECLARE_EVENT_CLASS(xdp_redirect_template,
TP_PROTO(const struct net_device *dev,
const struct bpf_prog *xdp,
const void *tgt, int err,
- const struct bpf_map *map, u32 index),
+ enum bpf_map_type map_type,
+ u32 map_id, u32 index),
- TP_ARGS(dev, xdp, tgt, err, map, index),
+ TP_ARGS(dev, xdp, tgt, err, map_type, map_id, index),
TP_STRUCT__entry(
__field(int, prog_id)
@@ -111,14 +107,22 @@ DECLARE_EVENT_CLASS(xdp_redirect_template,
),
TP_fast_assign(
+ u32 ifindex = 0, map_index = index;
+
+ if (map_type == BPF_MAP_TYPE_DEVMAP || map_type == BPF_MAP_TYPE_DEVMAP_HASH) {
+ ifindex = ((struct _bpf_dtab_netdev *)tgt)->dev->ifindex;
+ } else if (map_type == BPF_MAP_TYPE_UNSPEC && map_id == INT_MAX) {
+ ifindex = index;
+ map_index = 0;
+ }
+
__entry->prog_id = xdp->aux->id;
__entry->act = XDP_REDIRECT;
__entry->ifindex = dev->ifindex;
__entry->err = err;
- __entry->to_ifindex = map ? devmap_ifindex(tgt, map) :
- index;
- __entry->map_id = map ? map->id : 0;
- __entry->map_index = map ? index : 0;
+ __entry->to_ifindex = ifindex;
+ __entry->map_id = map_id;
+ __entry->map_index = map_index;
),
TP_printk("prog_id=%d action=%s ifindex=%d to_ifindex=%d err=%d"
@@ -133,45 +137,49 @@ DEFINE_EVENT(xdp_redirect_template, xdp_redirect,
TP_PROTO(const struct net_device *dev,
const struct bpf_prog *xdp,
const void *tgt, int err,
- const struct bpf_map *map, u32 index),
- TP_ARGS(dev, xdp, tgt, err, map, index)
+ enum bpf_map_type map_type,
+ u32 map_id, u32 index),
+ TP_ARGS(dev, xdp, tgt, err, map_type, map_id, index)
);
DEFINE_EVENT(xdp_redirect_template, xdp_redirect_err,
TP_PROTO(const struct net_device *dev,
const struct bpf_prog *xdp,
const void *tgt, int err,
- const struct bpf_map *map, u32 index),
- TP_ARGS(dev, xdp, tgt, err, map, index)
+ enum bpf_map_type map_type,
+ u32 map_id, u32 index),
+ TP_ARGS(dev, xdp, tgt, err, map_type, map_id, index)
);
-#define _trace_xdp_redirect(dev, xdp, to) \
- trace_xdp_redirect(dev, xdp, NULL, 0, NULL, to)
+#define _trace_xdp_redirect(dev, xdp, to) \
+ trace_xdp_redirect(dev, xdp, NULL, 0, BPF_MAP_TYPE_UNSPEC, INT_MAX, to)
-#define _trace_xdp_redirect_err(dev, xdp, to, err) \
- trace_xdp_redirect_err(dev, xdp, NULL, err, NULL, to)
+#define _trace_xdp_redirect_err(dev, xdp, to, err) \
+ trace_xdp_redirect_err(dev, xdp, NULL, err, BPF_MAP_TYPE_UNSPEC, INT_MAX, to)
-#define _trace_xdp_redirect_map(dev, xdp, to, map, index) \
- trace_xdp_redirect(dev, xdp, to, 0, map, index)
+#define _trace_xdp_redirect_map(dev, xdp, to, map_type, map_id, index) \
+ trace_xdp_redirect(dev, xdp, to, 0, map_type, map_id, index)
-#define _trace_xdp_redirect_map_err(dev, xdp, to, map, index, err) \
- trace_xdp_redirect_err(dev, xdp, to, err, map, index)
+#define _trace_xdp_redirect_map_err(dev, xdp, to, map_type, map_id, index, err) \
+ trace_xdp_redirect_err(dev, xdp, to, err, map_type, map_id, index)
/* not used anymore, but kept around so as not to break old programs */
DEFINE_EVENT(xdp_redirect_template, xdp_redirect_map,
TP_PROTO(const struct net_device *dev,
const struct bpf_prog *xdp,
const void *tgt, int err,
- const struct bpf_map *map, u32 index),
- TP_ARGS(dev, xdp, tgt, err, map, index)
+ enum bpf_map_type map_type,
+ u32 map_id, u32 index),
+ TP_ARGS(dev, xdp, tgt, err, map_type, map_id, index)
);
DEFINE_EVENT(xdp_redirect_template, xdp_redirect_map_err,
TP_PROTO(const struct net_device *dev,
const struct bpf_prog *xdp,
const void *tgt, int err,
- const struct bpf_map *map, u32 index),
- TP_ARGS(dev, xdp, tgt, err, map, index)
+ enum bpf_map_type map_type,
+ u32 map_id, u32 index),
+ TP_ARGS(dev, xdp, tgt, err, map_type, map_id, index)
);
TRACE_EVENT(xdp_cpumap_kthread,
diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c
index 5d1469de6921..0cf2791d5099 100644
--- a/kernel/bpf/cpumap.c
+++ b/kernel/bpf/cpumap.c
@@ -543,7 +543,6 @@ static void cpu_map_free(struct bpf_map *map)
* complete.
*/
- bpf_clear_redirect_map(map);
synchronize_rcu();
/* For cpu_map the remote CPUs can still be using the entries
@@ -563,7 +562,7 @@ static void cpu_map_free(struct bpf_map *map)
kfree(cmap);
}
-struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key)
+static void *__cpu_map_lookup_elem(struct bpf_map *map, u32 key)
{
struct bpf_cpu_map *cmap = container_of(map, struct bpf_cpu_map, map);
struct bpf_cpu_map_entry *rcpu;
@@ -600,6 +599,11 @@ static int cpu_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
return 0;
}
+static int cpu_map_redirect(struct bpf_map *map, u32 ifindex, u64 flags)
+{
+ return __bpf_xdp_redirect_map(map, ifindex, flags, __cpu_map_lookup_elem);
+}
+
static int cpu_map_btf_id;
const struct bpf_map_ops cpu_map_ops = {
.map_meta_equal = bpf_map_meta_equal,
@@ -612,6 +616,7 @@ const struct bpf_map_ops cpu_map_ops = {
.map_check_btf = map_check_no_btf,
.map_btf_name = "bpf_cpu_map",
.map_btf_id = &cpu_map_btf_id,
+ .map_redirect = cpu_map_redirect,
};
static void bq_flush_to_queue(struct xdp_bulk_queue *bq)
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index 85d9d1b72a33..7a5ad7331c3b 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -197,7 +197,6 @@ static void dev_map_free(struct bpf_map *map)
list_del_rcu(&dtab->list);
spin_unlock(&dev_map_lock);
- bpf_clear_redirect_map(map);
synchronize_rcu();
/* Make sure prior __dev_map_entry_free() have completed. */
@@ -258,7 +257,7 @@ static int dev_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
return 0;
}
-struct bpf_dtab_netdev *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key)
+static void *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key)
{
struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map);
struct hlist_head *head = dev_map_index_hash(dtab, key);
@@ -392,7 +391,7 @@ void __dev_flush(void)
* update happens in parallel here a dev_put wont happen until after reading the
* ifindex.
*/
-struct bpf_dtab_netdev *__dev_map_lookup_elem(struct bpf_map *map, u32 key)
+static void *__dev_map_lookup_elem(struct bpf_map *map, u32 key)
{
struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map);
struct bpf_dtab_netdev *obj;
@@ -735,6 +734,16 @@ static int dev_map_hash_update_elem(struct bpf_map *map, void *key, void *value,
map, key, value, map_flags);
}
+static int dev_map_redirect(struct bpf_map *map, u32 ifindex, u64 flags)
+{
+ return __bpf_xdp_redirect_map(map, ifindex, flags, __dev_map_lookup_elem);
+}
+
+static int dev_hash_map_redirect(struct bpf_map *map, u32 ifindex, u64 flags)
+{
+ return __bpf_xdp_redirect_map(map, ifindex, flags, __dev_map_hash_lookup_elem);
+}
+
static int dev_map_btf_id;
const struct bpf_map_ops dev_map_ops = {
.map_meta_equal = bpf_map_meta_equal,
@@ -747,6 +756,7 @@ const struct bpf_map_ops dev_map_ops = {
.map_check_btf = map_check_no_btf,
.map_btf_name = "bpf_dtab",
.map_btf_id = &dev_map_btf_id,
+ .map_redirect = dev_map_redirect,
};
static int dev_map_hash_map_btf_id;
@@ -761,6 +771,7 @@ const struct bpf_map_ops dev_map_hash_ops = {
.map_check_btf = map_check_no_btf,
.map_btf_name = "bpf_dtab",
.map_btf_id = &dev_map_hash_map_btf_id,
+ .map_redirect = dev_hash_map_redirect,
};
static void dev_map_hash_remove_netdev(struct bpf_dtab *dtab,
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 9fe90ce52a65..97eb0b2435b8 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -5582,7 +5582,8 @@ record_func_map(struct bpf_verifier_env *env, struct bpf_call_arg_meta *meta,
func_id != BPF_FUNC_map_push_elem &&
func_id != BPF_FUNC_map_pop_elem &&
func_id != BPF_FUNC_map_peek_elem &&
- func_id != BPF_FUNC_for_each_map_elem)
+ func_id != BPF_FUNC_for_each_map_elem &&
+ func_id != BPF_FUNC_redirect_map)
return 0;
if (map == NULL) {
@@ -12017,7 +12018,8 @@ static int do_misc_fixups(struct bpf_verifier_env *env)
insn->imm == BPF_FUNC_map_delete_elem ||
insn->imm == BPF_FUNC_map_push_elem ||
insn->imm == BPF_FUNC_map_pop_elem ||
- insn->imm == BPF_FUNC_map_peek_elem)) {
+ insn->imm == BPF_FUNC_map_peek_elem ||
+ insn->imm == BPF_FUNC_redirect_map)) {
aux = &env->insn_aux_data[i + delta];
if (bpf_map_ptr_poisoned(aux))
goto patch_call_imm;
@@ -12059,6 +12061,9 @@ static int do_misc_fixups(struct bpf_verifier_env *env)
(int (*)(struct bpf_map *map, void *value))NULL));
BUILD_BUG_ON(!__same_type(ops->map_peek_elem,
(int (*)(struct bpf_map *map, void *value))NULL));
+ BUILD_BUG_ON(!__same_type(ops->map_redirect,
+ (int (*)(struct bpf_map *map, u32 ifindex, u64 flags))NULL));
+
patch_map_ops_generic:
switch (insn->imm) {
case BPF_FUNC_map_lookup_elem:
@@ -12085,6 +12090,10 @@ patch_map_ops_generic:
insn->imm = BPF_CAST_CALL(ops->map_peek_elem) -
__bpf_call_base;
continue;
+ case BPF_FUNC_redirect_map:
+ insn->imm = BPF_CAST_CALL(ops->map_redirect) -
+ __bpf_call_base;
+ continue;
}
goto patch_call_imm;
diff --git a/net/core/filter.c b/net/core/filter.c
index 588b19ba0da8..b6732000d8a2 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -3918,23 +3918,6 @@ static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = {
.arg2_type = ARG_ANYTHING,
};
-static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd,
- struct bpf_map *map, struct xdp_buff *xdp)
-{
- switch (map->map_type) {
- case BPF_MAP_TYPE_DEVMAP:
- case BPF_MAP_TYPE_DEVMAP_HASH:
- return dev_map_enqueue(fwd, xdp, dev_rx);
- case BPF_MAP_TYPE_CPUMAP:
- return cpu_map_enqueue(fwd, xdp, dev_rx);
- case BPF_MAP_TYPE_XSKMAP:
- return __xsk_map_redirect(fwd, xdp);
- default:
- return -EBADRQC;
- }
- return 0;
-}
-
void xdp_do_flush(void)
{
__dev_flush();
@@ -3943,71 +3926,52 @@ void xdp_do_flush(void)
}
EXPORT_SYMBOL_GPL(xdp_do_flush);
-static inline void *__xdp_map_lookup_elem(struct bpf_map *map, u32 index)
-{
- switch (map->map_type) {
- case BPF_MAP_TYPE_DEVMAP:
- return __dev_map_lookup_elem(map, index);
- case BPF_MAP_TYPE_DEVMAP_HASH:
- return __dev_map_hash_lookup_elem(map, index);
- case BPF_MAP_TYPE_CPUMAP:
- return __cpu_map_lookup_elem(map, index);
- case BPF_MAP_TYPE_XSKMAP:
- return __xsk_map_lookup_elem(map, index);
- default:
- return NULL;
- }
-}
-
-void bpf_clear_redirect_map(struct bpf_map *map)
-{
- struct bpf_redirect_info *ri;
- int cpu;
-
- for_each_possible_cpu(cpu) {
- ri = per_cpu_ptr(&bpf_redirect_info, cpu);
- /* Avoid polluting remote cacheline due to writes if
- * not needed. Once we pass this test, we need the
- * cmpxchg() to make sure it hasn't been changed in
- * the meantime by remote CPU.
- */
- if (unlikely(READ_ONCE(ri->map) == map))
- cmpxchg(&ri->map, map, NULL);
- }
-}
-
int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
struct bpf_prog *xdp_prog)
{
struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
- struct bpf_map *map = READ_ONCE(ri->map);
- u32 index = ri->tgt_index;
+ enum bpf_map_type map_type = ri->map_type;
void *fwd = ri->tgt_value;
+ u32 map_id = ri->map_id;
int err;
- ri->tgt_index = 0;
- ri->tgt_value = NULL;
- WRITE_ONCE(ri->map, NULL);
+ ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
+ ri->map_type = BPF_MAP_TYPE_UNSPEC;
- if (unlikely(!map)) {
- fwd = dev_get_by_index_rcu(dev_net(dev), index);
- if (unlikely(!fwd)) {
- err = -EINVAL;
- goto err;
+ switch (map_type) {
+ case BPF_MAP_TYPE_DEVMAP:
+ fallthrough;
+ case BPF_MAP_TYPE_DEVMAP_HASH:
+ err = dev_map_enqueue(fwd, xdp, dev);
+ break;
+ case BPF_MAP_TYPE_CPUMAP:
+ err = cpu_map_enqueue(fwd, xdp, dev);
+ break;
+ case BPF_MAP_TYPE_XSKMAP:
+ err = __xsk_map_redirect(fwd, xdp);
+ break;
+ case BPF_MAP_TYPE_UNSPEC:
+ if (map_id == INT_MAX) {
+ fwd = dev_get_by_index_rcu(dev_net(dev), ri->tgt_index);
+ if (unlikely(!fwd)) {
+ err = -EINVAL;
+ break;
+ }
+ err = dev_xdp_enqueue(fwd, xdp, dev);
+ break;
}
-
- err = dev_xdp_enqueue(fwd, xdp, dev);
- } else {
- err = __bpf_tx_xdp_map(dev, fwd, map, xdp);
+ fallthrough;
+ default:
+ err = -EBADRQC;
}
if (unlikely(err))
goto err;
- _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index);
+ _trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
return 0;
err:
- _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err);
+ _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
return err;
}
EXPORT_SYMBOL_GPL(xdp_do_redirect);
@@ -4016,41 +3980,36 @@ static int xdp_do_generic_redirect_map(struct net_device *dev,
struct sk_buff *skb,
struct xdp_buff *xdp,
struct bpf_prog *xdp_prog,
- struct bpf_map *map)
+ void *fwd,
+ enum bpf_map_type map_type, u32 map_id)
{
struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
- u32 index = ri->tgt_index;
- void *fwd = ri->tgt_value;
- int err = 0;
-
- ri->tgt_index = 0;
- ri->tgt_value = NULL;
- WRITE_ONCE(ri->map, NULL);
-
- if (map->map_type == BPF_MAP_TYPE_DEVMAP ||
- map->map_type == BPF_MAP_TYPE_DEVMAP_HASH) {
- struct bpf_dtab_netdev *dst = fwd;
+ int err;
- err = dev_map_generic_redirect(dst, skb, xdp_prog);
+ switch (map_type) {
+ case BPF_MAP_TYPE_DEVMAP:
+ fallthrough;
+ case BPF_MAP_TYPE_DEVMAP_HASH:
+ err = dev_map_generic_redirect(fwd, skb, xdp_prog);
if (unlikely(err))
goto err;
- } else if (map->map_type == BPF_MAP_TYPE_XSKMAP) {
- struct xdp_sock *xs = fwd;
-
- err = xsk_generic_rcv(xs, xdp);
+ break;
+ case BPF_MAP_TYPE_XSKMAP:
+ err = xsk_generic_rcv(fwd, xdp);
if (err)
goto err;
consume_skb(skb);
- } else {
+ break;
+ default:
/* TODO: Handle BPF_MAP_TYPE_CPUMAP */
err = -EBADRQC;
goto err;
}
- _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index);
+ _trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
return 0;
err:
- _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err);
+ _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
return err;
}
@@ -4058,31 +4017,34 @@ int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
struct xdp_buff *xdp, struct bpf_prog *xdp_prog)
{
struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
- struct bpf_map *map = READ_ONCE(ri->map);
- u32 index = ri->tgt_index;
- struct net_device *fwd;
- int err = 0;
-
- if (map)
- return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog,
- map);
- ri->tgt_index = 0;
- fwd = dev_get_by_index_rcu(dev_net(dev), index);
- if (unlikely(!fwd)) {
- err = -EINVAL;
- goto err;
- }
+ enum bpf_map_type map_type = ri->map_type;
+ void *fwd = ri->tgt_value;
+ u32 map_id = ri->map_id;
+ int err;
- err = xdp_ok_fwd_dev(fwd, skb->len);
- if (unlikely(err))
- goto err;
+ ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
+ ri->map_type = BPF_MAP_TYPE_UNSPEC;
- skb->dev = fwd;
- _trace_xdp_redirect(dev, xdp_prog, index);
- generic_xdp_tx(skb, xdp_prog);
- return 0;
+ if (map_type == BPF_MAP_TYPE_UNSPEC && map_id == INT_MAX) {
+ fwd = dev_get_by_index_rcu(dev_net(dev), ri->tgt_index);
+ if (unlikely(!fwd)) {
+ err = -EINVAL;
+ goto err;
+ }
+
+ err = xdp_ok_fwd_dev(fwd, skb->len);
+ if (unlikely(err))
+ goto err;
+
+ skb->dev = fwd;
+ _trace_xdp_redirect(dev, xdp_prog, ri->tgt_index);
+ generic_xdp_tx(skb, xdp_prog);
+ return 0;
+ }
+
+ return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog, fwd, map_type, map_id);
err:
- _trace_xdp_redirect_err(dev, xdp_prog, index, err);
+ _trace_xdp_redirect_err(dev, xdp_prog, ri->tgt_index, err);
return err;
}
@@ -4093,10 +4055,12 @@ BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags)
if (unlikely(flags))
return XDP_ABORTED;
- ri->flags = flags;
+ /* NB! Map type UNSPEC and map_id == INT_MAX (never generated
+ * by map_idr) is used for ifindex based XDP redirect.
+ */
ri->tgt_index = ifindex;
- ri->tgt_value = NULL;
- WRITE_ONCE(ri->map, NULL);
+ ri->map_id = INT_MAX;
+ ri->map_type = BPF_MAP_TYPE_UNSPEC;
return XDP_REDIRECT;
}
@@ -4112,28 +4076,7 @@ static const struct bpf_func_proto bpf_xdp_redirect_proto = {
BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex,
u64, flags)
{
- struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
-
- /* Lower bits of the flags are used as return code on lookup failure */
- if (unlikely(flags > XDP_TX))
- return XDP_ABORTED;
-
- ri->tgt_value = __xdp_map_lookup_elem(map, ifindex);
- if (unlikely(!ri->tgt_value)) {
- /* If the lookup fails we want to clear out the state in the
- * redirect_info struct completely, so that if an eBPF program
- * performs multiple lookups, the last one always takes
- * precedence.
- */
- WRITE_ONCE(ri->map, NULL);
- return flags;
- }
-
- ri->flags = flags;
- ri->tgt_index = ifindex;
- WRITE_ONCE(ri->map, map);
-
- return XDP_REDIRECT;
+ return map->ops->map_redirect(map, ifindex, flags);
}
static const struct bpf_func_proto bpf_xdp_redirect_map_proto = {
diff --git a/net/xdp/xskmap.c b/net/xdp/xskmap.c
index 113fd9017203..67b4ce504852 100644
--- a/net/xdp/xskmap.c
+++ b/net/xdp/xskmap.c
@@ -87,7 +87,6 @@ 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);
}
@@ -125,6 +124,16 @@ static int xsk_map_gen_lookup(struct bpf_map *map, struct bpf_insn *insn_buf)
return insn - insn_buf;
}
+static void *__xsk_map_lookup_elem(struct bpf_map *map, u32 key)
+{
+ struct xsk_map *m = container_of(map, struct xsk_map, map);
+
+ if (key >= map->max_entries)
+ return NULL;
+
+ return READ_ONCE(m->xsk_map[key]);
+}
+
static void *xsk_map_lookup_elem(struct bpf_map *map, void *key)
{
WARN_ON_ONCE(!rcu_read_lock_held());
@@ -215,6 +224,11 @@ static int xsk_map_delete_elem(struct bpf_map *map, void *key)
return 0;
}
+static int xsk_map_redirect(struct bpf_map *map, u32 ifindex, u64 flags)
+{
+ return __bpf_xdp_redirect_map(map, ifindex, flags, __xsk_map_lookup_elem);
+}
+
void xsk_map_try_sock_delete(struct xsk_map *map, struct xdp_sock *xs,
struct xdp_sock **map_entry)
{
@@ -247,4 +261,5 @@ const struct bpf_map_ops xsk_map_ops = {
.map_check_btf = map_check_no_btf,
.map_btf_name = "xsk_map",
.map_btf_id = &xsk_map_btf_id,
+ .map_redirect = xsk_map_redirect,
};