samples/bpf: fix a build issue

With latest net-next:

====
clang  -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/6.3.1/include -I./arch/x86/include -I./arch/x86/include/generated/uapi -I./arch/x86/include/generated  -I./include -I./arch/x86/include/uapi -I./include/uapi -I./include/generated/uapi -include ./include/linux/kconfig.h  -Isamples/bpf \
    -D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \
    -Wno-compare-distinct-pointer-types \
    -Wno-gnu-variable-sized-type-not-at-end \
    -Wno-address-of-packed-member -Wno-tautological-compare \
    -Wno-unknown-warning-option \
    -O2 -emit-llvm -c samples/bpf/tcp_synrto_kern.c -o -| llc -march=bpf -filetype=obj -o samples/bpf/tcp_synrto_kern.o
samples/bpf/tcp_synrto_kern.c:20:10: fatal error: 'bpf_endian.h' file not found
          ^~~~~~~~~~~~~~
1 error generated.
====

net has the same issue.

Add support for ntohl and htonl in tools/testing/selftests/bpf/bpf_endian.h.
Also move bpf_helpers.h from samples/bpf to selftests/bpf and change
compiler include logic so that programs in samples/bpf can access the headers
in selftests/bpf, but not the other way around.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 1 insertions, 198 deletions

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 9c650589e80f..87246be6feb8 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -207,6 +207,7 @@ $(obj)/tracex5_kern.o: $(obj)/syscall_nrs.h
 # useless for BPF samples.
 $(obj)/%.o: $(src)/%.c
 	$(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) -I$(obj) \
+		-I$(srctree)/tools/testing/selftests/bpf/ \
 		-D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \
 		-Wno-compare-distinct-pointer-types \
 		-Wno-gnu-variable-sized-type-not-at-end \
diff --git a/samples/bpf/bpf_helpers.h b/samples/bpf/bpf_helpers.h
deleted file mode 100644
index d50ac342dc92..000000000000
--- a/samples/bpf/bpf_helpers.h
+++ /dev/null
@@ -1,198 +0,0 @@
-#ifndef __BPF_HELPERS_H
-#define __BPF_HELPERS_H
-
-/* helper macro to place programs, maps, license in
- * different sections in elf_bpf file. Section names
- * are interpreted by elf_bpf loader
- */
-#define SEC(NAME) __attribute__((section(NAME), used))
-
-/* helper functions called from eBPF programs written in C */
-static void *(*bpf_map_lookup_elem)(void *map, void *key) =
-	(void *) BPF_FUNC_map_lookup_elem;
-static int (*bpf_map_update_elem)(void *map, void *key, void *value,
-				  unsigned long long flags) =
-	(void *) BPF_FUNC_map_update_elem;
-static int (*bpf_map_delete_elem)(void *map, void *key) =
-	(void *) BPF_FUNC_map_delete_elem;
-static int (*bpf_probe_read)(void *dst, int size, void *unsafe_ptr) =
-	(void *) BPF_FUNC_probe_read;
-static unsigned long long (*bpf_ktime_get_ns)(void) =
-	(void *) BPF_FUNC_ktime_get_ns;
-static int (*bpf_trace_printk)(const char *fmt, int fmt_size, ...) =
-	(void *) BPF_FUNC_trace_printk;
-static void (*bpf_tail_call)(void *ctx, void *map, int index) =
-	(void *) BPF_FUNC_tail_call;
-static unsigned long long (*bpf_get_smp_processor_id)(void) =
-	(void *) BPF_FUNC_get_smp_processor_id;
-static unsigned long long (*bpf_get_current_pid_tgid)(void) =
-	(void *) BPF_FUNC_get_current_pid_tgid;
-static unsigned long long (*bpf_get_current_uid_gid)(void) =
-	(void *) BPF_FUNC_get_current_uid_gid;
-static int (*bpf_get_current_comm)(void *buf, int buf_size) =
-	(void *) BPF_FUNC_get_current_comm;
-static unsigned long long (*bpf_perf_event_read)(void *map,
-						 unsigned long long flags) =
-	(void *) BPF_FUNC_perf_event_read;
-static int (*bpf_clone_redirect)(void *ctx, int ifindex, int flags) =
-	(void *) BPF_FUNC_clone_redirect;
-static int (*bpf_redirect)(int ifindex, int flags) =
-	(void *) BPF_FUNC_redirect;
-static int (*bpf_perf_event_output)(void *ctx, void *map,
-				    unsigned long long flags, void *data,
-				    int size) =
-	(void *) BPF_FUNC_perf_event_output;
-static int (*bpf_get_stackid)(void *ctx, void *map, int flags) =
-	(void *) BPF_FUNC_get_stackid;
-static int (*bpf_probe_write_user)(void *dst, void *src, int size) =
-	(void *) BPF_FUNC_probe_write_user;
-static int (*bpf_current_task_under_cgroup)(void *map, int index) =
-	(void *) BPF_FUNC_current_task_under_cgroup;
-static int (*bpf_skb_get_tunnel_key)(void *ctx, void *key, int size, int flags) =
-	(void *) BPF_FUNC_skb_get_tunnel_key;
-static int (*bpf_skb_set_tunnel_key)(void *ctx, void *key, int size, int flags) =
-	(void *) BPF_FUNC_skb_set_tunnel_key;
-static int (*bpf_skb_get_tunnel_opt)(void *ctx, void *md, int size) =
-	(void *) BPF_FUNC_skb_get_tunnel_opt;
-static int (*bpf_skb_set_tunnel_opt)(void *ctx, void *md, int size) =
-	(void *) BPF_FUNC_skb_set_tunnel_opt;
-static unsigned long long (*bpf_get_prandom_u32)(void) =
-	(void *) BPF_FUNC_get_prandom_u32;
-static int (*bpf_xdp_adjust_head)(void *ctx, int offset) =
-	(void *) BPF_FUNC_xdp_adjust_head;
-static int (*bpf_setsockopt)(void *ctx, int level, int optname, void *optval,
-			     int optlen) =
-	(void *) BPF_FUNC_setsockopt;
-
-/* llvm builtin functions that eBPF C program may use to
- * emit BPF_LD_ABS and BPF_LD_IND instructions
- */
-struct sk_buff;
-unsigned long long load_byte(void *skb,
-			     unsigned long long off) asm("llvm.bpf.load.byte");
-unsigned long long load_half(void *skb,
-			     unsigned long long off) asm("llvm.bpf.load.half");
-unsigned long long load_word(void *skb,
-			     unsigned long long off) asm("llvm.bpf.load.word");
-
-/* a helper structure used by eBPF C program
- * to describe map attributes to elf_bpf loader
- */
-struct bpf_map_def {
-	unsigned int type;
-	unsigned int key_size;
-	unsigned int value_size;
-	unsigned int max_entries;
-	unsigned int map_flags;
-	unsigned int inner_map_idx;
-};
-
-static int (*bpf_skb_load_bytes)(void *ctx, int off, void *to, int len) =
-	(void *) BPF_FUNC_skb_load_bytes;
-static int (*bpf_skb_store_bytes)(void *ctx, int off, void *from, int len, int flags) =
-	(void *) BPF_FUNC_skb_store_bytes;
-static int (*bpf_l3_csum_replace)(void *ctx, int off, int from, int to, int flags) =
-	(void *) BPF_FUNC_l3_csum_replace;
-static int (*bpf_l4_csum_replace)(void *ctx, int off, int from, int to, int flags) =
-	(void *) BPF_FUNC_l4_csum_replace;
-static int (*bpf_skb_under_cgroup)(void *ctx, void *map, int index) =
-	(void *) BPF_FUNC_skb_under_cgroup;
-static int (*bpf_skb_change_head)(void *, int len, int flags) =
-	(void *) BPF_FUNC_skb_change_head;
-
-#if defined(__x86_64__)
-
-#define PT_REGS_PARM1(x) ((x)->di)
-#define PT_REGS_PARM2(x) ((x)->si)
-#define PT_REGS_PARM3(x) ((x)->dx)
-#define PT_REGS_PARM4(x) ((x)->cx)
-#define PT_REGS_PARM5(x) ((x)->r8)
-#define PT_REGS_RET(x) ((x)->sp)
-#define PT_REGS_FP(x) ((x)->bp)
-#define PT_REGS_RC(x) ((x)->ax)
-#define PT_REGS_SP(x) ((x)->sp)
-#define PT_REGS_IP(x) ((x)->ip)
-
-#elif defined(__s390x__)
-
-#define PT_REGS_PARM1(x) ((x)->gprs[2])
-#define PT_REGS_PARM2(x) ((x)->gprs[3])
-#define PT_REGS_PARM3(x) ((x)->gprs[4])
-#define PT_REGS_PARM4(x) ((x)->gprs[5])
-#define PT_REGS_PARM5(x) ((x)->gprs[6])
-#define PT_REGS_RET(x) ((x)->gprs[14])
-#define PT_REGS_FP(x) ((x)->gprs[11]) /* Works only with CONFIG_FRAME_POINTER */
-#define PT_REGS_RC(x) ((x)->gprs[2])
-#define PT_REGS_SP(x) ((x)->gprs[15])
-#define PT_REGS_IP(x) ((x)->psw.addr)
-
-#elif defined(__aarch64__)
-
-#define PT_REGS_PARM1(x) ((x)->regs[0])
-#define PT_REGS_PARM2(x) ((x)->regs[1])
-#define PT_REGS_PARM3(x) ((x)->regs[2])
-#define PT_REGS_PARM4(x) ((x)->regs[3])
-#define PT_REGS_PARM5(x) ((x)->regs[4])
-#define PT_REGS_RET(x) ((x)->regs[30])
-#define PT_REGS_FP(x) ((x)->regs[29]) /* Works only with CONFIG_FRAME_POINTER */
-#define PT_REGS_RC(x) ((x)->regs[0])
-#define PT_REGS_SP(x) ((x)->sp)
-#define PT_REGS_IP(x) ((x)->pc)
-
-#elif defined(__mips__)
-
-#define PT_REGS_PARM1(x) ((x)->regs[4])
-#define PT_REGS_PARM2(x) ((x)->regs[5])
-#define PT_REGS_PARM3(x) ((x)->regs[6])
-#define PT_REGS_PARM4(x) ((x)->regs[7])
-#define PT_REGS_PARM5(x) ((x)->regs[8])
-#define PT_REGS_RET(x) ((x)->regs[31])
-#define PT_REGS_FP(x) ((x)->regs[30]) /* Works only with CONFIG_FRAME_POINTER */
-#define PT_REGS_RC(x) ((x)->regs[1])
-#define PT_REGS_SP(x) ((x)->regs[29])
-#define PT_REGS_IP(x) ((x)->cp0_epc)
-
-#elif defined(__powerpc__)
-
-#define PT_REGS_PARM1(x) ((x)->gpr[3])
-#define PT_REGS_PARM2(x) ((x)->gpr[4])
-#define PT_REGS_PARM3(x) ((x)->gpr[5])
-#define PT_REGS_PARM4(x) ((x)->gpr[6])
-#define PT_REGS_PARM5(x) ((x)->gpr[7])
-#define PT_REGS_RC(x) ((x)->gpr[3])
-#define PT_REGS_SP(x) ((x)->sp)
-#define PT_REGS_IP(x) ((x)->nip)
-
-#elif defined(__sparc__)
-
-#define PT_REGS_PARM1(x) ((x)->u_regs[UREG_I0])
-#define PT_REGS_PARM2(x) ((x)->u_regs[UREG_I1])
-#define PT_REGS_PARM3(x) ((x)->u_regs[UREG_I2])
-#define PT_REGS_PARM4(x) ((x)->u_regs[UREG_I3])
-#define PT_REGS_PARM5(x) ((x)->u_regs[UREG_I4])
-#define PT_REGS_RET(x) ((x)->u_regs[UREG_I7])
-#define PT_REGS_RC(x) ((x)->u_regs[UREG_I0])
-#define PT_REGS_SP(x) ((x)->u_regs[UREG_FP])
-#if defined(__arch64__)
-#define PT_REGS_IP(x) ((x)->tpc)
-#else
-#define PT_REGS_IP(x) ((x)->pc)
-#endif
-
-#endif
-
-#ifdef __powerpc__
-#define BPF_KPROBE_READ_RET_IP(ip, ctx)		({ (ip) = (ctx)->link; })
-#define BPF_KRETPROBE_READ_RET_IP		BPF_KPROBE_READ_RET_IP
-#elif defined(__sparc__)
-#define BPF_KPROBE_READ_RET_IP(ip, ctx)		({ (ip) = PT_REGS_RET(ctx); })
-#define BPF_KRETPROBE_READ_RET_IP		BPF_KPROBE_READ_RET_IP
-#else
-#define BPF_KPROBE_READ_RET_IP(ip, ctx)		({				\
-		bpf_probe_read(&(ip), sizeof(ip), (void *)PT_REGS_RET(ctx)); })
-#define BPF_KRETPROBE_READ_RET_IP(ip, ctx)	({				\
-		bpf_probe_read(&(ip), sizeof(ip),				\
-				(void *)(PT_REGS_FP(ctx) + sizeof(ip))); })
-#endif
-
-#endif