bpf: offload: allow netdev to disappear while verifier is running
To allow verifier instruction callbacks without any extra locking
NETDEV_UNREGISTER notification would wait on a waitqueue for verifier
to finish. This design decision was made when rtnl lock was providing
all the locking. Use the read/write lock instead and remove the
workqueue.
Verifier will now call into the offload code, so dev_ops are moved
to offload structure. Since verifier calls are all under
bpf_prog_is_dev_bound() we no longer need static inline implementations
to please builds with CONFIG_NET=n.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 838eee1..669549f 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -17,6 +17,7 @@
#include <linux/numa.h>
#include <linux/wait.h>
+struct bpf_verifier_env;
struct perf_event;
struct bpf_prog;
struct bpf_map;
@@ -184,14 +185,18 @@ struct bpf_verifier_ops {
struct bpf_prog *prog, u32 *target_size);
};
+struct bpf_prog_offload_ops {
+ int (*insn_hook)(struct bpf_verifier_env *env,
+ int insn_idx, int prev_insn_idx);
+};
+
struct bpf_dev_offload {
struct bpf_prog *prog;
struct net_device *netdev;
void *dev_priv;
struct list_head offloads;
bool dev_state;
- bool verifier_running;
- wait_queue_head_t verifier_done;
+ const struct bpf_prog_offload_ops *dev_ops;
};
struct bpf_prog_aux {
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index 883a35d..2feb218 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -166,12 +166,6 @@ static inline bool bpf_verifier_log_full(const struct bpf_verifer_log *log)
return log->len_used >= log->len_total - 1;
}
-struct bpf_verifier_env;
-struct bpf_ext_analyzer_ops {
- int (*insn_hook)(struct bpf_verifier_env *env,
- int insn_idx, int prev_insn_idx);
-};
-
#define BPF_MAX_SUBPROGS 256
/* single container for all structs
@@ -185,7 +179,6 @@ struct bpf_verifier_env {
bool strict_alignment; /* perform strict pointer alignment checks */
struct bpf_verifier_state *cur_state; /* current verifier state */
struct bpf_verifier_state_list **explored_states; /* search pruning optimization */
- const struct bpf_ext_analyzer_ops *dev_ops; /* device analyzer ops */
struct bpf_map *used_maps[MAX_USED_MAPS]; /* array of map's used by eBPF program */
u32 used_map_cnt; /* number of used maps */
u32 id_gen; /* used to generate unique reg IDs */
@@ -206,13 +199,8 @@ static inline struct bpf_reg_state *cur_regs(struct bpf_verifier_env *env)
return cur->frame[cur->curframe]->regs;
}
-#if defined(CONFIG_NET) && defined(CONFIG_BPF_SYSCALL)
int bpf_prog_offload_verifier_prep(struct bpf_verifier_env *env);
-#else
-static inline int bpf_prog_offload_verifier_prep(struct bpf_verifier_env *env)
-{
- return -EOPNOTSUPP;
-}
-#endif
+int bpf_prog_offload_verify_insn(struct bpf_verifier_env *env,
+ int insn_idx, int prev_insn_idx);
#endif /* _LINUX_BPF_VERIFIER_H */
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 352066e..49bfc6e 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -804,7 +804,7 @@ enum bpf_netdev_command {
BPF_OFFLOAD_DESTROY,
};
-struct bpf_ext_analyzer_ops;
+struct bpf_prog_offload_ops;
struct netlink_ext_ack;
struct netdev_bpf {
@@ -826,7 +826,7 @@ struct netdev_bpf {
/* BPF_OFFLOAD_VERIFIER_PREP */
struct {
struct bpf_prog *prog;
- const struct bpf_ext_analyzer_ops *ops; /* callee set */
+ const struct bpf_prog_offload_ops *ops; /* callee set */
} verifier;
/* BPF_OFFLOAD_TRANSLATE, BPF_OFFLOAD_DESTROY */
struct {