bpf: add msg_pop_data helper to tools

Add the necessary header definitions to tools for new
msg_pop_data_helper.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 23e2031..597afdb 100644 (file)
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -2268,6 +2268,19 @@ union bpf_attr {
  *
  *     Return
  *             0 on success, or a negative error in case of failure.
+ *
+ * int bpf_msg_pop_data(struct sk_msg_buff *msg, u32 start, u32 pop, u64 flags)
+ *      Description
+ *             Will remove *pop* bytes from a *msg* starting at byte *start*.
+ *             This may result in **ENOMEM** errors under certain situations if
+ *             an allocation and copy are required due to a full ring buffer.
+ *             However, the helper will try to avoid doing the allocation
+ *             if possible. Other errors can occur if input parameters are
+ *             invalid either due to *start* byte not being valid part of msg
+ *             payload and/or *pop* value being to large.
+ *
+ *     Return
+ *             0 on success, or a negative erro in case of failure.
  */
 #define __BPF_FUNC_MAPPER(FN)          \
        FN(unspec),                     \
@@ -2360,7 +2373,8 @@ union bpf_attr {
        FN(map_push_elem),              \
        FN(map_pop_elem),               \
        FN(map_peek_elem),              \
-       FN(msg_push_data),
+       FN(msg_push_data),              \
+       FN(msg_pop_data),
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
  * function eBPF program intends to call

diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
index 686e57c..7b69519 100644 (file)
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -113,6 +113,8 @@ static int (*bpf_msg_pull_data)(void *ctx, int start, int end, int flags) =
        (void *) BPF_FUNC_msg_pull_data;
 static int (*bpf_msg_push_data)(void *ctx, int start, int end, int flags) =
        (void *) BPF_FUNC_msg_push_data;
+static int (*bpf_msg_pop_data)(void *ctx, int start, int cut, int flags) =
+       (void *) BPF_FUNC_msg_pop_data;
 static int (*bpf_bind)(void *ctx, void *addr, int addr_len) =
        (void *) BPF_FUNC_bind;
 static int (*bpf_xdp_adjust_tail)(void *ctx, int offset) =