Per net/bpf/test_run.c, particular prog types have additional
restrictions around the parameters that can be provided, so document
these in the header.
I didn't bother documenting the limitation on duration for raw
tracepoints since that's an output parameter anyway.
Tested with ./tools/testing/selftests/bpf/test_doc_build.sh.
Suggested-by: Yonghong Song <yhs@xxxxxx>
Signed-off-by: Joe Stringer <joe@xxxxxxxxx>
---
CC: Lorenz Bauer <lmb@xxxxxxxxxxxxxx>
CC: Song Liu <songliubraving@xxxxxx>
CC: Stanislav Fomichev <sdf@xxxxxxxxxx>
---
include/uapi/linux/bpf.h | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 49371eba98ba..e1ee1be7e49b 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -312,6 +312,27 @@ union bpf_iter_link_info {
* *ctx_out*, *data_out* (for example, packet data), result of the
* execution *retval*, and *duration* of the test run.
*
+ * The sizes of the buffers provided as input and output
+ * parameters *ctx_in*, *ctx_out*, *data_in*, and *data_out* must
+ * be provided in the corresponding variables *ctx_size_in*,
+ * *ctx_size_out*, *data_size_in*, and/or *data_size_out*. If any
+ * of these parameters are not provided (ie set to NULL), the
+ * corresponding size field must be zero.
+ *
+ * Some program types have particular requirements:
+ *
+ * **BPF_PROG_TYPE_SK_LOOKUP**
+ * *data_in* and *data_out* must be NULL.
+ *
+ * **BPF_PROG_TYPE_XDP**
+ * *ctx_in* and *ctx_out* must be NULL.
+ *
+ * **BPF_PROG_TYPE_RAW_TRACEPOINT**,
+ * **BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE**
+ *
+ * *ctx_out*, *data_in* and *data_out* must be NULL.
+ * *repeat* must be zero.
+ *
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
--
2.27.0
