Commit d56b63cf authored by Benjamin Tissoires's avatar Benjamin Tissoires Committed by Alexei Starovoitov
Browse files

bpf: add support for bpf_wq user type 



Mostly a copy/paste from the bpf_timer API, without the initialization
and free, as they will be done in a separate patch.

Signed-off-by: default avatarBenjamin Tissoires <bentiss@kernel.org>
Link: https://lore.kernel.org/r/20240420-bpf_wq-v2-5-6c986a5a741f@kernel.org


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent fc22d949

include/linux/bpf.h

+10 −1
Original line number Diff line number Diff line
@@ -185,7 +185,7 @@ struct bpf_map_ops { 


enum {

	/* Support at most 10 fields in a BTF type */

	BTF_FIELDS_MAX	   = 10,

	BTF_FIELDS_MAX	   = 11,

};



enum btf_field_type {
@@ -202,6 +202,7 @@ enum btf_field_type { 
	BPF_GRAPH_NODE = BPF_RB_NODE | BPF_LIST_NODE,

	BPF_GRAPH_ROOT = BPF_RB_ROOT | BPF_LIST_HEAD,

	BPF_REFCOUNT   = (1 << 9),

	BPF_WORKQUEUE  = (1 << 10),

};



typedef void (*btf_dtor_kfunc_t)(void *);
@@ -238,6 +239,7 @@ struct btf_record { 
	u32 field_mask;

	int spin_lock_off;

	int timer_off;

	int wq_off;

	int refcount_off;

	struct btf_field fields[];

};
@@ -312,6 +314,8 @@ static inline const char *btf_field_type_name(enum btf_field_type type) 
		return "bpf_spin_lock";

	case BPF_TIMER:

		return "bpf_timer";

	case BPF_WORKQUEUE:

		return "bpf_wq";

	case BPF_KPTR_UNREF:

	case BPF_KPTR_REF:

		return "kptr";
@@ -340,6 +344,8 @@ static inline u32 btf_field_type_size(enum btf_field_type type) 
		return sizeof(struct bpf_spin_lock);

	case BPF_TIMER:

		return sizeof(struct bpf_timer);

	case BPF_WORKQUEUE:

		return sizeof(struct bpf_wq);

	case BPF_KPTR_UNREF:

	case BPF_KPTR_REF:

	case BPF_KPTR_PERCPU:
@@ -367,6 +373,8 @@ static inline u32 btf_field_type_align(enum btf_field_type type) 
		return __alignof__(struct bpf_spin_lock);

	case BPF_TIMER:

		return __alignof__(struct bpf_timer);

	case BPF_WORKQUEUE:

		return __alignof__(struct bpf_wq);

	case BPF_KPTR_UNREF:

	case BPF_KPTR_REF:

	case BPF_KPTR_PERCPU:
@@ -406,6 +414,7 @@ static inline void bpf_obj_init_field(const struct btf_field *field, void *addr) 
		/* RB_ROOT_CACHED 0-inits, no need to do anything after memset */

	case BPF_SPIN_LOCK:

	case BPF_TIMER:

	case BPF_WORKQUEUE:

	case BPF_KPTR_UNREF:

	case BPF_KPTR_REF:

	case BPF_KPTR_PERCPU:

include/uapi/linux/bpf.h

+4 −0
Original line number Diff line number Diff line
@@ -7306,6 +7306,10 @@ struct bpf_timer { 
	__u64 __opaque[2];

} __attribute__((aligned(8)));



struct bpf_wq {

	__u64 __opaque[2];

} __attribute__((aligned(8)));



struct bpf_dynptr {

	__u64 __opaque[2];

} __attribute__((aligned(8)));

kernel/bpf/btf.c

+17 −0
Original line number Diff line number Diff line
@@ -3464,6 +3464,15 @@ static int btf_get_field_type(const char *name, u32 field_mask, u32 *seen_mask, 
			goto end;

		}

	}

	if (field_mask & BPF_WORKQUEUE) {

		if (!strcmp(name, "bpf_wq")) {

			if (*seen_mask & BPF_WORKQUEUE)

				return -E2BIG;

			*seen_mask |= BPF_WORKQUEUE;

			type = BPF_WORKQUEUE;

			goto end;

		}

	}

	field_mask_test_name(BPF_LIST_HEAD, "bpf_list_head");

	field_mask_test_name(BPF_LIST_NODE, "bpf_list_node");

	field_mask_test_name(BPF_RB_ROOT,   "bpf_rb_root");
@@ -3515,6 +3524,7 @@ static int btf_find_struct_field(const struct btf *btf, 
		switch (field_type) {

		case BPF_SPIN_LOCK:

		case BPF_TIMER:

		case BPF_WORKQUEUE:

		case BPF_LIST_NODE:

		case BPF_RB_NODE:

		case BPF_REFCOUNT:
@@ -3582,6 +3592,7 @@ static int btf_find_datasec_var(const struct btf *btf, const struct btf_type *t, 
		switch (field_type) {

		case BPF_SPIN_LOCK:

		case BPF_TIMER:

		case BPF_WORKQUEUE:

		case BPF_LIST_NODE:

		case BPF_RB_NODE:

		case BPF_REFCOUNT:
@@ -3816,6 +3827,7 @@ struct btf_record *btf_parse_fields(const struct btf *btf, const struct btf_type 


	rec->spin_lock_off = -EINVAL;

	rec->timer_off = -EINVAL;

	rec->wq_off = -EINVAL;

	rec->refcount_off = -EINVAL;

	for (i = 0; i < cnt; i++) {

		field_type_size = btf_field_type_size(info_arr[i].type);
@@ -3846,6 +3858,11 @@ struct btf_record *btf_parse_fields(const struct btf *btf, const struct btf_type 
			/* Cache offset for faster lookup at runtime */

			rec->timer_off = rec->fields[i].offset;

			break;

		case BPF_WORKQUEUE:

			WARN_ON_ONCE(rec->wq_off >= 0);

			/* Cache offset for faster lookup at runtime */

			rec->wq_off = rec->fields[i].offset;

			break;

		case BPF_REFCOUNT:

			WARN_ON_ONCE(rec->refcount_off >= 0);

			/* Cache offset for faster lookup at runtime */

kernel/bpf/syscall.c

+5 −1
Original line number Diff line number Diff line
@@ -559,6 +559,7 @@ void btf_record_free(struct btf_record *rec) 
		case BPF_SPIN_LOCK:

		case BPF_TIMER:

		case BPF_REFCOUNT:

		case BPF_WORKQUEUE:

			/* Nothing to release */

			break;

		default:
@@ -608,6 +609,7 @@ struct btf_record *btf_record_dup(const struct btf_record *rec) 
		case BPF_SPIN_LOCK:

		case BPF_TIMER:

		case BPF_REFCOUNT:

		case BPF_WORKQUEUE:

			/* Nothing to acquire */

			break;

		default:
@@ -679,6 +681,8 @@ void bpf_obj_free_fields(const struct btf_record *rec, void *obj) 
		case BPF_TIMER:

			bpf_timer_cancel_and_free(field_ptr);

			break;

		case BPF_WORKQUEUE:

			break;

		case BPF_KPTR_UNREF:

			WRITE_ONCE(*(u64 *)field_ptr, 0);

			break;
@@ -1085,7 +1089,7 @@ static int map_check_btf(struct bpf_map *map, struct bpf_token *token, 


	map->record = btf_parse_fields(btf, value_type,

				       BPF_SPIN_LOCK | BPF_TIMER | BPF_KPTR | BPF_LIST_HEAD |

				       BPF_RB_ROOT | BPF_REFCOUNT,

				       BPF_RB_ROOT | BPF_REFCOUNT | BPF_WORKQUEUE,

				       map->value_size);

	if (!IS_ERR_OR_NULL(map->record)) {

		int i;

kernel/bpf/verifier.c

+9 −0
Original line number Diff line number Diff line
@@ -1838,6 +1838,8 @@ static void mark_ptr_not_null_reg(struct bpf_reg_state *reg) 
			 */

			if (btf_record_has_field(map->inner_map_meta->record, BPF_TIMER))

				reg->map_uid = reg->id;

			if (btf_record_has_field(map->inner_map_meta->record, BPF_WORKQUEUE))

				reg->map_uid = reg->id;

		} else if (map->map_type == BPF_MAP_TYPE_XSKMAP) {

			reg->type = PTR_TO_XDP_SOCK;

		} else if (map->map_type == BPF_MAP_TYPE_SOCKMAP ||
@@ -18141,6 +18143,13 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env, 
		}

	}









	if (btf_record_has_field(map->record, BPF_WORKQUEUE)) {









		if (is_tracing_prog_type(prog_type)) {









			verbose(env, "tracing progs cannot use bpf_wq yet\n");









			return -EINVAL;









		}









	}

















	if ((bpf_prog_is_offloaded(prog->aux) || bpf_map_is_offloaded(map)) &&









	    !bpf_offload_prog_map_match(prog, map)) {









		verbose(env, "offload device mismatch between prog and map\n");