Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Alexei Starovoitov says:

====================
pull-request: bpf-next 2021-05-19

The following pull-request contains BPF updates for your *net-next* tree.

We've added 43 non-merge commits during the last 11 day(s) which contain
a total of 74 files changed, 3717 insertions(+), 578 deletions(-).

The main changes are:

1) syscall program type, fd array, and light skeleton, from Alexei.

2) Stop emitting static variables in skeleton, from Andrii.

3) Low level tc-bpf api, from Kumar.

4) Reduce verifier kmalloc/kfree churn, from Lorenz.
====================

include/uapi/linux/bpf.h

@@ -837,6 +837,7 @@ enum bpf_cmd {
 	BPF_PROG_ATTACH,
 	BPF_PROG_DETACH,
 	BPF_PROG_TEST_RUN,
+	BPF_PROG_RUN = BPF_PROG_TEST_RUN,
 	BPF_PROG_GET_NEXT_ID,
 	BPF_MAP_GET_NEXT_ID,
 	BPF_PROG_GET_FD_BY_ID,
@@ -937,6 +938,7 @@ enum bpf_prog_type {
 	BPF_PROG_TYPE_EXT,
 	BPF_PROG_TYPE_LSM,
 	BPF_PROG_TYPE_SK_LOOKUP,
+	BPF_PROG_TYPE_SYSCALL, /* a program that can execute syscalls */
 };
 
 enum bpf_attach_type {
@@ -1097,8 +1099,8 @@ enum bpf_link_type {
 /* When BPF ldimm64's insn[0].src_reg != 0 then this can have
  * the following extensions:
  *
- * insn[0].src_reg:  BPF_PSEUDO_MAP_FD
- * insn[0].imm:      map fd
+ * insn[0].src_reg:  BPF_PSEUDO_MAP_[FD|IDX]
+ * insn[0].imm:      map fd or fd_idx
  * insn[1].imm:      0
  * insn[0].off:      0
  * insn[1].off:      0
@@ -1106,15 +1108,19 @@ enum bpf_link_type {
  * verifier type:    CONST_PTR_TO_MAP
  */
 #define BPF_PSEUDO_MAP_FD	1
-/* insn[0].src_reg:  BPF_PSEUDO_MAP_VALUE
- * insn[0].imm:      map fd
+#define BPF_PSEUDO_MAP_IDX	5
+
+/* insn[0].src_reg:  BPF_PSEUDO_MAP_[IDX_]VALUE
+ * insn[0].imm:      map fd or fd_idx
  * insn[1].imm:      offset into value
  * insn[0].off:      0
  * insn[1].off:      0
  * ldimm64 rewrite:  address of map[0]+offset
  * verifier type:    PTR_TO_MAP_VALUE
  */
-#define BPF_PSEUDO_MAP_VALUE	2
+#define BPF_PSEUDO_MAP_VALUE		2
+#define BPF_PSEUDO_MAP_IDX_VALUE	6
+
 /* insn[0].src_reg:  BPF_PSEUDO_BTF_ID
  * insn[0].imm:      kernel btd id of VAR
  * insn[1].imm:      0
@@ -1314,6 +1320,8 @@ union bpf_attr {
 			/* or valid module BTF object fd or 0 to attach to vmlinux */
 			__u32		attach_btf_obj_fd;
 		};
+		__u32		:32;		/* pad */
+		__aligned_u64	fd_array;	/* array of FDs */
 	};
 
 	struct { /* anonymous struct used by BPF_OBJ_* commands */
@@ -4735,6 +4743,24 @@ union bpf_attr {
  *		be zero-terminated except when **str_size** is 0.
  *
  *		Or **-EBUSY** if the per-CPU memory copy buffer is busy.
+ *
+ * long bpf_sys_bpf(u32 cmd, void *attr, u32 attr_size)
+ * 	Description
+ * 		Execute bpf syscall with given arguments.
+ * 	Return
+ * 		A syscall result.
+ *
+ * long bpf_btf_find_by_name_kind(char *name, int name_sz, u32 kind, int flags)
+ * 	Description
+ * 		Find BTF type with given name and kind in vmlinux BTF or in module's BTFs.
+ * 	Return
+ * 		Returns btf_id and btf_obj_fd in lower and upper 32 bits.
+ *
+ * long bpf_sys_close(u32 fd)
+ * 	Description
+ * 		Execute close syscall for given FD.
+ * 	Return
+ * 		A syscall result.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -4903,6 +4929,9 @@ union bpf_attr {
 	FN(check_mtu),			\
 	FN(for_each_map_elem),		\
 	FN(snprintf),			\
+	FN(sys_bpf),			\
+	FN(btf_find_by_name_kind),	\
+	FN(sys_close),			\
 	/* */
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper