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/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
#ifndef __BPF_HELPERS__
#define __BPF_HELPERS__
#include "bpf_helper_defs.h"
#define __uint(name, val) int (*name)[val]
#define __type(name, val) typeof(val) *name
/* helper macro to print out debug messages */
#define bpf_printk(fmt, ...) \
({ \
char ____fmt[] = fmt; \
bpf_trace_printk(____fmt, sizeof(____fmt), \
##__VA_ARGS__); \
})
#ifdef __clang__
/* 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))
/* 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;
unsigned int numa_node;
};
#else
#include <bpf-helpers.h>
#endif
#define BPF_ANNOTATE_KV_PAIR(name, type_key, type_val) \
struct ____btf_map_##name { \
type_key key; \
type_val value; \
}; \
struct ____btf_map_##name \
__attribute__ ((section(".maps." #name), used)) \
____btf_map_##name = { }
/* Scan the ARCH passed in from ARCH env variable (see Makefile) */
#if defined(__TARGET_ARCH_x86)
#define bpf_target_x86
#define bpf_target_defined
#elif defined(__TARGET_ARCH_s390)
#define bpf_target_s390
#define bpf_target_defined
#elif defined(__TARGET_ARCH_arm)
#define bpf_target_arm
#define bpf_target_defined
#elif defined(__TARGET_ARCH_arm64)
#define bpf_target_arm64
#define bpf_target_defined
#elif defined(__TARGET_ARCH_mips)
#define bpf_target_mips
#define bpf_target_defined
#elif defined(__TARGET_ARCH_powerpc)
#define bpf_target_powerpc
#define bpf_target_defined
#elif defined(__TARGET_ARCH_sparc)
#define bpf_target_sparc
#define bpf_target_defined
#else
#undef bpf_target_defined
#endif
/* Fall back to what the compiler says */
#ifndef bpf_target_defined
#if defined(__x86_64__)
#define bpf_target_x86
#elif defined(__s390__)
#define bpf_target_s390
#elif defined(__arm__)
#define bpf_target_arm
#elif defined(__aarch64__)
#define bpf_target_arm64
#elif defined(__mips__)
#define bpf_target_mips
#elif defined(__powerpc__)
#define bpf_target_powerpc
#elif defined(__sparc__)
#define bpf_target_sparc
#endif
#endif
#if defined(bpf_target_x86)
#ifdef __KERNEL__
#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)
#else
#ifdef __i386__
/* i386 kernel is built with -mregparm=3 */
#define PT_REGS_PARM1(x) ((x)->eax)
#define PT_REGS_PARM2(x) ((x)->edx)
#define PT_REGS_PARM3(x) ((x)->ecx)
#define PT_REGS_PARM4(x) 0
#define PT_REGS_PARM5(x) 0
#define PT_REGS_RET(x) ((x)->esp)
#define PT_REGS_FP(x) ((x)->ebp)
#define PT_REGS_RC(x) ((x)->eax)
#define PT_REGS_SP(x) ((x)->esp)
#define PT_REGS_IP(x) ((x)->eip)
#else
#define PT_REGS_PARM1(x) ((x)->rdi)
#define PT_REGS_PARM2(x) ((x)->rsi)
#define PT_REGS_PARM3(x) ((x)->rdx)
#define PT_REGS_PARM4(x) ((x)->rcx)
#define PT_REGS_PARM5(x) ((x)->r8)
#define PT_REGS_RET(x) ((x)->rsp)
#define PT_REGS_FP(x) ((x)->rbp)
#define PT_REGS_RC(x) ((x)->rax)
#define PT_REGS_SP(x) ((x)->rsp)
#define PT_REGS_IP(x) ((x)->rip)
#endif
#endif
#elif defined(bpf_target_s390)
/* s390 provides user_pt_regs instead of struct pt_regs to userspace */
struct pt_regs;
#define PT_REGS_S390 const volatile user_pt_regs
#define PT_REGS_PARM1(x) (((PT_REGS_S390 *)(x))->gprs[2])
#define PT_REGS_PARM2(x) (((PT_REGS_S390 *)(x))->gprs[3])
#define PT_REGS_PARM3(x) (((PT_REGS_S390 *)(x))->gprs[4])
#define PT_REGS_PARM4(x) (((PT_REGS_S390 *)(x))->gprs[5])
#define PT_REGS_PARM5(x) (((PT_REGS_S390 *)(x))->gprs[6])
#define PT_REGS_RET(x) (((PT_REGS_S390 *)(x))->gprs[14])
/* Works only with CONFIG_FRAME_POINTER */
#define PT_REGS_FP(x) (((PT_REGS_S390 *)(x))->gprs[11])
#define PT_REGS_RC(x) (((PT_REGS_S390 *)(x))->gprs[2])
#define PT_REGS_SP(x) (((PT_REGS_S390 *)(x))->gprs[15])
#define PT_REGS_IP(x) (((PT_REGS_S390 *)(x))->psw.addr)
#elif defined(bpf_target_arm)
#define PT_REGS_PARM1(x) ((x)->uregs[0])
#define PT_REGS_PARM2(x) ((x)->uregs[1])
#define PT_REGS_PARM3(x) ((x)->uregs[2])
#define PT_REGS_PARM4(x) ((x)->uregs[3])
#define PT_REGS_PARM5(x) ((x)->uregs[4])
#define PT_REGS_RET(x) ((x)->uregs[14])
#define PT_REGS_FP(x) ((x)->uregs[11]) /* Works only with CONFIG_FRAME_POINTER */
#define PT_REGS_RC(x) ((x)->uregs[0])
#define PT_REGS_SP(x) ((x)->uregs[13])
#define PT_REGS_IP(x) ((x)->uregs[12])
#elif defined(bpf_target_arm64)
/* arm64 provides struct user_pt_regs instead of struct pt_regs to userspace */
struct pt_regs;
#define PT_REGS_ARM64 const volatile struct user_pt_regs
#define PT_REGS_PARM1(x) (((PT_REGS_ARM64 *)(x))->regs[0])
#define PT_REGS_PARM2(x) (((PT_REGS_ARM64 *)(x))->regs[1])
#define PT_REGS_PARM3(x) (((PT_REGS_ARM64 *)(x))->regs[2])
#define PT_REGS_PARM4(x) (((PT_REGS_ARM64 *)(x))->regs[3])
#define PT_REGS_PARM5(x) (((PT_REGS_ARM64 *)(x))->regs[4])
#define PT_REGS_RET(x) (((PT_REGS_ARM64 *)(x))->regs[30])
/* Works only with CONFIG_FRAME_POINTER */
#define PT_REGS_FP(x) (((PT_REGS_ARM64 *)(x))->regs[29])
#define PT_REGS_RC(x) (((PT_REGS_ARM64 *)(x))->regs[0])
#define PT_REGS_SP(x) (((PT_REGS_ARM64 *)(x))->sp)
#define PT_REGS_IP(x) (((PT_REGS_ARM64 *)(x))->pc)
#elif defined(bpf_target_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(bpf_target_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(bpf_target_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])
/* Should this also be a bpf_target check for the sparc case? */
#if defined(__arch64__)
#define PT_REGS_IP(x) ((x)->tpc)
#else
#define PT_REGS_IP(x) ((x)->pc)
#endif
#endif
#if defined(bpf_target_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(bpf_target_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
/*
* BPF_CORE_READ abstracts away bpf_probe_read() call and captures offset
* relocation for source address using __builtin_preserve_access_index()
* built-in, provided by Clang.
*
* __builtin_preserve_access_index() takes as an argument an expression of
* taking an address of a field within struct/union. It makes compiler emit
* a relocation, which records BTF type ID describing root struct/union and an
* accessor string which describes exact embedded field that was used to take
* an address. See detailed description of this relocation format and
* semantics in comments to struct bpf_offset_reloc in libbpf_internal.h.
*
* This relocation allows libbpf to adjust BPF instruction to use correct
* actual field offset, based on target kernel BTF type that matches original
* (local) BTF, used to record relocation.
*/
#define BPF_CORE_READ(dst, src) \
bpf_probe_read((dst), sizeof(*(src)), \
__builtin_preserve_access_index(src))
#endif
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