1 files changed, 55 insertions, 4 deletions

diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 793103b10eab..3075018a4ef8 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -110,6 +110,12 @@ union bpf_iter_link_info {
 		__u32	cgroup_fd;
 		__u64	cgroup_id;
 	} cgroup;
+	/* Parameters of task iterators. */
+	struct {
+		__u32	tid;
+		__u32	pid;
+		__u32	pid_fd;
+	} task;
 };
 
 /* BPF syscall commands, see bpf(2) man-page for more details. */
@@ -928,6 +934,7 @@ enum bpf_map_type {
 	BPF_MAP_TYPE_INODE_STORAGE,
 	BPF_MAP_TYPE_TASK_STORAGE,
 	BPF_MAP_TYPE_BLOOM_FILTER,
+	BPF_MAP_TYPE_USER_RINGBUF,
 };
 
 /* Note that tracing related programs such as
@@ -4950,6 +4957,7 @@ union bpf_attr {
  * 		Get address of the traced function (for tracing and kprobe programs).
  * 	Return
  * 		Address of the traced function.
+ * 		0 for kprobes placed within the function (not at the entry).
  *
  * u64 bpf_get_attach_cookie(void *ctx)
  * 	Description
@@ -5079,12 +5087,12 @@ union bpf_attr {
  *
  * long bpf_get_func_arg(void *ctx, u32 n, u64 *value)
  *	Description
- *		Get **n**-th argument (zero based) of the traced function (for tracing programs)
+ *		Get **n**-th argument register (zero based) of the traced function (for tracing programs)
  *		returned in **value**.
  *
  *	Return
  *		0 on success.
- *		**-EINVAL** if n >= arguments count of traced function.
+ *		**-EINVAL** if n >= argument register count of traced function.
  *
  * long bpf_get_func_ret(void *ctx, u64 *value)
  *	Description
@@ -5097,10 +5105,11 @@ union bpf_attr {
  *
  * long bpf_get_func_arg_cnt(void *ctx)
  *	Description
- *		Get number of arguments of the traced function (for tracing programs).
+ *		Get number of registers of the traced function (for tracing programs) where
+ *		function arguments are stored in these registers.
  *
  *	Return
- *		The number of arguments of the traced function.
+ *		The number of argument registers of the traced function.
  *
  * int bpf_get_retval(void)
  *	Description
@@ -5386,6 +5395,43 @@ union bpf_attr {
  *	Return
  *		Current *ktime*.
  *
+ * long bpf_user_ringbuf_drain(struct bpf_map *map, void *callback_fn, void *ctx, u64 flags)
+ *	Description
+ *		Drain samples from the specified user ring buffer, and invoke
+ *		the provided callback for each such sample:
+ *
+ *		long (\*callback_fn)(struct bpf_dynptr \*dynptr, void \*ctx);
+ *
+ *		If **callback_fn** returns 0, the helper will continue to try
+ *		and drain the next sample, up to a maximum of
+ *		BPF_MAX_USER_RINGBUF_SAMPLES samples. If the return value is 1,
+ *		the helper will skip the rest of the samples and return. Other
+ *		return values are not used now, and will be rejected by the
+ *		verifier.
+ *	Return
+ *		The number of drained samples if no error was encountered while
+ *		draining samples, or 0 if no samples were present in the ring
+ *		buffer. If a user-space producer was epoll-waiting on this map,
+ *		and at least one sample was drained, they will receive an event
+ *		notification notifying them of available space in the ring
+ *		buffer. If the BPF_RB_NO_WAKEUP flag is passed to this
+ *		function, no wakeup notification will be sent. If the
+ *		BPF_RB_FORCE_WAKEUP flag is passed, a wakeup notification will
+ *		be sent even if no sample was drained.
+ *
+ *		On failure, the returned value is one of the following:
+ *
+ *		**-EBUSY** if the ring buffer is contended, and another calling
+ *		context was concurrently draining the ring buffer.
+ *
+ *		**-EINVAL** if user-space is not properly tracking the ring
+ *		buffer due to the producer position not being aligned to 8
+ *		bytes, a sample not being aligned to 8 bytes, or the producer
+ *		position not matching the advertised length of a sample.
+ *
+ *		**-E2BIG** if user-space has tried to publish a sample which is
+ *		larger than the size of the ring buffer, or which cannot fit
+ *		within a struct bpf_dynptr.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -5597,6 +5643,7 @@ union bpf_attr {
 	FN(tcp_raw_check_syncookie_ipv4),	\
 	FN(tcp_raw_check_syncookie_ipv6),	\
 	FN(ktime_get_tai_ns),		\
+	FN(user_ringbuf_drain),		\
 	/* */
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
@@ -6218,6 +6265,10 @@ struct bpf_link_info {
 					__u64 cgroup_id;
 					__u32 order;
 				} cgroup;
+				struct {
+					__u32 tid;
+					__u32 pid;
+				} task;
 			};
 		} iter;
 		struct  {