Add bpf_struct_ops_id() to enable struct_ops implementors to use
struct_ops map id as the unique id of a struct_ops in their subsystem.
A subsystem that wishes to create a mapping between id and struct_ops
instance pointer can update the mapping accordingly during
bpf_struct_ops::reg(), unreg(), and update().
Signed-off-by: Amery Hung <ameryhung@xxxxxxxxx>
---
include/linux/bpf.h | 1 +
kernel/bpf/bpf_struct_ops.c | 12 ++++++++++++
2 files changed, 13 insertions(+)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index f9cd2164ed23..aa5347dee78c 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1975,6 +1975,7 @@ static inline void bpf_module_put(const void *data, struct module *owner)
module_put(owner);
}
int bpf_struct_ops_link_create(union bpf_attr *attr);
+u32 bpf_struct_ops_id(const void *kdata);
#ifdef CONFIG_NET
/* Define it here to avoid the use of forward declaration */
diff --git a/kernel/bpf/bpf_struct_ops.c b/kernel/bpf/bpf_struct_ops.c
index 687a3e9c76f5..a41e6730edcf 100644
--- a/kernel/bpf/bpf_struct_ops.c
+++ b/kernel/bpf/bpf_struct_ops.c
@@ -1174,6 +1174,18 @@ void bpf_struct_ops_put(const void *kdata)
bpf_map_put(&st_map->map);
}
+u32 bpf_struct_ops_id(const void *kdata)
+{
+ struct bpf_struct_ops_value *kvalue;
+ struct bpf_struct_ops_map *st_map;
+
+ kvalue = container_of(kdata, struct bpf_struct_ops_value, data);
+ st_map = container_of(kvalue, struct bpf_struct_ops_map, kvalue);
+
+ return st_map->map.id;
+}
+EXPORT_SYMBOL_GPL(bpf_struct_ops_id);
+
static bool bpf_struct_ops_valid_to_reg(struct bpf_map *map)
{
struct bpf_struct_ops_map *st_map = (struct bpf_struct_ops_map *)map;
--
2.47.3
