bpf: pass prog instead of env to bpf_prog_offload_verifier_prep()

Function bpf_prog_offload_verifier_prep(), called from the kernel BPF
verifier to run a driver-specific callback for preparing for the
verification step for offloaded programs, takes a pointer to a struct
bpf_verifier_env object. However, no driver callback needs the whole
structure at this time: the two drivers supporting this, nfp and
netdevsim, only need a pointer to the struct bpf_prog instance held by
env.

Update the callback accordingly, on kernel side and in these two
drivers.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

drivers/net/ethernet/netronome/nfp/bpf/offload.c

@@ -183,10 +183,9 @@ static void nfp_prog_free(struct nfp_prog *nfp_prog)
 }
 
 static int
-nfp_bpf_verifier_prep(struct net_device *netdev, struct bpf_verifier_env *env)
+nfp_bpf_verifier_prep(struct net_device *netdev, struct bpf_prog *prog)
 {
 	struct nfp_net *nn = netdev_priv(netdev);
-	struct bpf_prog *prog = env->prog;
 	struct nfp_app *app = nn->app;
 	struct nfp_prog *nfp_prog;
 	int ret;

drivers/net/netdevsim/bpf.c

@@ -259,14 +259,14 @@ static int nsim_bpf_create_prog(struct netdevsim *ns, struct bpf_prog *prog)
 }
 
 static int
-nsim_bpf_verifier_prep(struct net_device *dev, struct bpf_verifier_env *env)
+nsim_bpf_verifier_prep(struct net_device *dev, struct bpf_prog *prog)
 {
 	struct netdevsim *ns = netdev_priv(dev);
 
 	if (!ns->bpf_bind_accept)
 		return -EOPNOTSUPP;
 
-	return nsim_bpf_create_prog(ns, env->prog);
+	return nsim_bpf_create_prog(ns, prog);
 }
 
 static int nsim_bpf_translate(struct net_device *dev, struct bpf_prog *prog)

include/linux/bpf.h

@@ -268,7 +268,7 @@ struct bpf_prog_offload_ops {
 	int (*insn_hook)(struct bpf_verifier_env *env,
 			 int insn_idx, int prev_insn_idx);
 	int (*finalize)(struct bpf_verifier_env *env);
-	int (*prepare)(struct net_device *netdev, struct bpf_verifier_env *env);
+	int (*prepare)(struct net_device *netdev, struct bpf_prog *prog);
 	int (*translate)(struct net_device *netdev, struct bpf_prog *prog);
 	void (*destroy)(struct bpf_prog *prog);
 };

include/linux/bpf_verifier.h

@@ -245,7 +245,7 @@ static inline struct bpf_reg_state *cur_regs(struct bpf_verifier_env *env)
 	return cur_func(env)->regs;
 }
 
-int bpf_prog_offload_verifier_prep(struct bpf_verifier_env *env);
+int bpf_prog_offload_verifier_prep(struct bpf_prog *prog);
 int bpf_prog_offload_verify_insn(struct bpf_verifier_env *env,
 				 int insn_idx, int prev_insn_idx);
 int bpf_prog_offload_finalize(struct bpf_verifier_env *env);

kernel/bpf/offload.c

@@ -123,15 +123,15 @@ int bpf_prog_offload_init(struct bpf_prog *prog, union bpf_attr *attr)
 	return err;
 }
 
-int bpf_prog_offload_verifier_prep(struct bpf_verifier_env *env)
+int bpf_prog_offload_verifier_prep(struct bpf_prog *prog)
 {
 	struct bpf_prog_offload *offload;
 	int ret = -ENODEV;
 
 	down_read(&bpf_devs_lock);
-	offload = env->prog->aux->offload;
+	offload = prog->aux->offload;
 	if (offload)
-		ret = offload->offdev->ops->prepare(offload->netdev, env);
+		ret = offload->offdev->ops->prepare(offload->netdev, prog);
 	offload->dev_state = !ret;
 	up_read(&bpf_devs_lock);
 

kernel/bpf/verifier.c

@@ -6368,7 +6368,7 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr)
 		goto skip_full_check;
 
 	if (bpf_prog_is_dev_bound(env->prog->aux)) {
-		ret = bpf_prog_offload_verifier_prep(env);
+		ret = bpf_prog_offload_verifier_prep(env->prog);
 		if (ret)
 			goto skip_full_check;
 	}