[PATCH bpf-next 06/18] bpf: add support for bpf_wq user type
From: Benjamin Tissoires
Date: Tue Apr 16 2024 - 10:12:52 EST
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: Benjamin Tissoires <bentiss@xxxxxxxxxx>
---
include/linux/bpf.h | 11 ++++++++++-
include/uapi/linux/bpf.h | 4 ++++
kernel/bpf/btf.c | 17 +++++++++++++++++
kernel/bpf/syscall.c | 6 +++++-
kernel/bpf/verifier.c | 9 +++++++++
5 files changed, 45 insertions(+), 2 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 551445c47779..45cb13dfd15e 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -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:
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index cee0a7915c08..e4ae83550fb3 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -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)));
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 90c4a32d89ff..a9b5b28a2630 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -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 */
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 7d392ec83655..0848e4141b00 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -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;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 2aad6d90550f..deaf2e1ab690 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -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 ||
@@ -18155,6 +18157,13 @@ 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");
--
2.44.0