cregit-Linux how code gets into the kernel

Release 4.7 samples/bpf/bpf_helpers.h

Directory: samples/bpf
#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

Overall Contributors

PersonTokensPropCommitsCommitProp
alexei starovoitovalexei starovoitov53960.43%1071.43%
michael holzheumichael holzheu14115.81%17.14%
naveen n. raonaveen n. rao12113.57%17.14%
yang shiyang shi707.85%17.14%
xia kaixuxia kaixu212.35%17.14%
Total892100.00%14100.00%
Directory: samples/bpf
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