linux/kernel/bpf/map_iter.c, branch v5.8

bpf: Enable bpf_iter targets registering ctx argument types

2020-05-13T19:30:50Z

Commit b121b341e598 ("bpf: Add PTR_TO_BTF_ID_OR_NULL support") adds a field btf_id_or_null_non0_off to bpf_prog->aux structure to indicate that the first ctx argument is PTR_TO_BTF_ID reg_type and all others are PTR_TO_BTF_ID_OR_NULL. This approach does not really scale if we have other different reg types in the future, e.g., a pointer to a buffer. This patch enables bpf_iter targets registering ctx argument reg types which may be different from the default one. For example, for pointers to structures, the default reg_type is PTR_TO_BTF_ID for tracing program. The target can register a particular pointer type as PTR_TO_BTF_ID_OR_NULL which can be used by the verifier to enforce accesses. Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200513180221.2949882-1-yhs@fb.com

bpf: net: Refactor bpf_iter target registration

2020-05-13T19:30:50Z

Currently bpf_iter_reg_target takes parameters from target and allocates memory to save them. This is really not necessary, esp. in the future we may grow information passed from targets to bpf_iter manager. The patch refactors the code so target reg_info becomes static and bpf_iter manager can just take a reference to it. Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200513180219.2949605-1-yhs@fb.com

bpf: Add bpf_map iterator

2020-05-10T00:05:26Z

Implement seq_file operations to traverse all bpf_maps. Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200509175909.2476096-1-yhs@fb.com