kernel-fxtec-pro1x/samples/bpf/bpf_helpers.h
Naveen N. Rao 138d6153a1 samples/bpf: Enable powerpc support
Add the necessary definitions for building bpf samples on ppc.

Since ppc doesn't store function return address on the stack, modify how
PT_REGS_RET() and PT_REGS_FP() work.

Also, introduce PT_REGS_IP() to access the instruction pointer.

Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-06 16:01:29 -04:00

137 lines
4.9 KiB
C

#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 int (*bpf_perf_event_read)(void *map, int index) =
(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, int index, 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;
/* 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;
};
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;
#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)->ip)
#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(__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)
#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
#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