From db20fd2b01087bdfbe30bce314a198eefedcc42e Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Fri, 26 Sep 2014 00:16:59 -0700 Subject: bpf: add lookup/update/delete/iterate methods to BPF maps 'maps' is a generic storage of different types for sharing data between kernel and userspace. The maps are accessed from user space via BPF syscall, which has commands: - create a map with given type and attributes fd = bpf(BPF_MAP_CREATE, union bpf_attr *attr, u32 size) returns fd or negative error - lookup key in a given map referenced by fd err = bpf(BPF_MAP_LOOKUP_ELEM, union bpf_attr *attr, u32 size) using attr->map_fd, attr->key, attr->value returns zero and stores found elem into value or negative error - create or update key/value pair in a given map err = bpf(BPF_MAP_UPDATE_ELEM, union bpf_attr *attr, u32 size) using attr->map_fd, attr->key, attr->value returns zero or negative error - find and delete element by key in a given map err = bpf(BPF_MAP_DELETE_ELEM, union bpf_attr *attr, u32 size) using attr->map_fd, attr->key - iterate map elements (based on input key return next_key) err = bpf(BPF_MAP_GET_NEXT_KEY, union bpf_attr *attr, u32 size) using attr->map_fd, attr->key, attr->next_key - close(fd) deletes the map Signed-off-by: Alexei Starovoitov Signed-off-by: David S. Miller --- include/linux/bpf.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'include/linux/bpf.h') diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 48014a71f0fe..2887f3f9da59 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -9,6 +9,7 @@ #include #include +#include struct bpf_map; @@ -17,6 +18,12 @@ struct bpf_map_ops { /* funcs callable from userspace (via syscall) */ struct bpf_map *(*map_alloc)(union bpf_attr *attr); void (*map_free)(struct bpf_map *); + int (*map_get_next_key)(struct bpf_map *map, void *key, void *next_key); + + /* funcs callable from userspace and from eBPF programs */ + void *(*map_lookup_elem)(struct bpf_map *map, void *key); + int (*map_update_elem)(struct bpf_map *map, void *key, void *value); + int (*map_delete_elem)(struct bpf_map *map, void *key); }; struct bpf_map { @@ -37,5 +44,6 @@ struct bpf_map_type_list { void bpf_register_map_type(struct bpf_map_type_list *tl); void bpf_map_put(struct bpf_map *map); +struct bpf_map *bpf_map_get(struct fd f); #endif /* _LINUX_BPF_H */ -- cgit v1.2.3