/* Copyright (c) 2011-2015 PLUMgrid, http://plumgrid.com
+ * Copyright (c) 2016 Facebook
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/bpf.h>
+#include <linux/bpf_perf_event.h>
#include <linux/filter.h>
#include <linux/uaccess.h>
#include <linux/ctype.h>
}
EXPORT_SYMBOL_GPL(trace_call_bpf);
-static u64 bpf_probe_read(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+BPF_CALL_3(bpf_probe_read, void *, dst, u32, size, const void *, unsafe_ptr)
{
- void *dst = (void *) (long) r1;
- int ret, size = (int) r2;
- void *unsafe_ptr = (void *) (long) r3;
+ int ret;
ret = probe_kernel_read(dst, unsafe_ptr, size);
if (unlikely(ret < 0))
.arg3_type = ARG_ANYTHING,
};
-static u64 bpf_probe_write_user(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+BPF_CALL_3(bpf_probe_write_user, void *, unsafe_ptr, const void *, src,
+ u32, size)
{
- void *unsafe_ptr = (void *) (long) r1;
- void *src = (void *) (long) r2;
- int size = (int) r3;
-
/*
* Ensure we're in user context which is safe for the helper to
* run. This helper has no business in a kthread.
* limited trace_printk()
* only %d %u %x %ld %lu %lx %lld %llu %llx %p %s conversion specifiers allowed
*/
-static u64 bpf_trace_printk(u64 r1, u64 fmt_size, u64 r3, u64 r4, u64 r5)
+BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1,
+ u64, arg2, u64, arg3)
{
- char *fmt = (char *) (long) r1;
bool str_seen = false;
int mod[3] = {};
int fmt_cnt = 0;
switch (fmt_cnt) {
case 1:
- unsafe_addr = r3;
- r3 = (long) buf;
+ unsafe_addr = arg1;
+ arg1 = (long) buf;
break;
case 2:
- unsafe_addr = r4;
- r4 = (long) buf;
+ unsafe_addr = arg2;
+ arg2 = (long) buf;
break;
case 3:
- unsafe_addr = r5;
- r5 = (long) buf;
+ unsafe_addr = arg3;
+ arg3 = (long) buf;
break;
}
buf[0] = 0;
}
return __trace_printk(1/* fake ip will not be printed */, fmt,
- mod[0] == 2 ? r3 : mod[0] == 1 ? (long) r3 : (u32) r3,
- mod[1] == 2 ? r4 : mod[1] == 1 ? (long) r4 : (u32) r4,
- mod[2] == 2 ? r5 : mod[2] == 1 ? (long) r5 : (u32) r5);
+ mod[0] == 2 ? arg1 : mod[0] == 1 ? (long) arg1 : (u32) arg1,
+ mod[1] == 2 ? arg2 : mod[1] == 1 ? (long) arg2 : (u32) arg2,
+ mod[2] == 2 ? arg3 : mod[2] == 1 ? (long) arg3 : (u32) arg3);
}
static const struct bpf_func_proto bpf_trace_printk_proto = {
return &bpf_trace_printk_proto;
}
-static u64 bpf_perf_event_read(u64 r1, u64 flags, u64 r3, u64 r4, u64 r5)
+BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags)
{
- struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
struct bpf_array *array = container_of(map, struct bpf_array, map);
unsigned int cpu = smp_processor_id();
u64 index = flags & BPF_F_INDEX_MASK;
return 0;
}
-static u64 bpf_perf_event_output(u64 r1, u64 r2, u64 flags, u64 r4, u64 size)
+BPF_CALL_5(bpf_perf_event_output, struct pt_regs *, regs, struct bpf_map *, map,
+ u64, flags, void *, data, u64, size)
{
- struct pt_regs *regs = (struct pt_regs *)(long) r1;
- struct bpf_map *map = (struct bpf_map *)(long) r2;
- void *data = (void *)(long) r4;
struct perf_raw_record raw = {
.frag = {
.size = size,
return __bpf_perf_event_output(regs, map, flags, &raw);
}
-static u64 bpf_get_current_task(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+BPF_CALL_0(bpf_get_current_task)
{
return (long) current;
}
.ret_type = RET_INTEGER,
};
-static u64 bpf_current_task_under_cgroup(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+BPF_CALL_2(bpf_current_task_under_cgroup, struct bpf_map *, map, u32, idx)
{
- struct bpf_map *map = (struct bpf_map *)(long)r1;
struct bpf_array *array = container_of(map, struct bpf_array, map);
struct cgroup *cgrp;
- u32 idx = (u32)r2;
if (unlikely(in_interrupt()))
return -EINVAL;
-
if (unlikely(idx >= array->map.max_entries))
return -E2BIG;
.type = BPF_PROG_TYPE_KPROBE,
};
-static u64 bpf_perf_event_output_tp(u64 r1, u64 r2, u64 index, u64 r4, u64 size)
+BPF_CALL_5(bpf_perf_event_output_tp, void *, tp_buff, struct bpf_map *, map,
+ u64, flags, void *, data, u64, size)
{
+ struct pt_regs *regs = *(struct pt_regs **)tp_buff;
+
/*
* r1 points to perf tracepoint buffer where first 8 bytes are hidden
* from bpf program and contain a pointer to 'struct pt_regs'. Fetch it
- * from there and call the same bpf_perf_event_output() helper
+ * from there and call the same bpf_perf_event_output() helper inline.
*/
- u64 ctx = *(long *)(uintptr_t)r1;
-
- return bpf_perf_event_output(ctx, r2, index, r4, size);
+ return ____bpf_perf_event_output(regs, map, flags, data, size);
}
static const struct bpf_func_proto bpf_perf_event_output_proto_tp = {
.arg5_type = ARG_CONST_STACK_SIZE,
};
-static u64 bpf_get_stackid_tp(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+BPF_CALL_3(bpf_get_stackid_tp, void *, tp_buff, struct bpf_map *, map,
+ u64, flags)
{
- u64 ctx = *(long *)(uintptr_t)r1;
+ struct pt_regs *regs = *(struct pt_regs **)tp_buff;
- return bpf_get_stackid(ctx, r2, r3, r4, r5);
+ /*
+ * Same comment as in bpf_perf_event_output_tp(), only that this time
+ * the other helper's function body cannot be inlined due to being
+ * external, thus we need to call raw helper function.
+ */
+ return bpf_get_stackid((unsigned long) regs, (unsigned long) map,
+ flags, 0, 0);
}
static const struct bpf_func_proto bpf_get_stackid_proto_tp = {
.type = BPF_PROG_TYPE_TRACEPOINT,
};
+static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
+ enum bpf_reg_type *reg_type)
+{
+ if (off < 0 || off >= sizeof(struct bpf_perf_event_data))
+ return false;
+ if (type != BPF_READ)
+ return false;
+ if (off % size != 0)
+ return false;
+ if (off == offsetof(struct bpf_perf_event_data, sample_period)) {
+ if (size != sizeof(u64))
+ return false;
+ } else {
+ if (size != sizeof(long))
+ return false;
+ }
+ return true;
+}
+
+static u32 pe_prog_convert_ctx_access(enum bpf_access_type type, int dst_reg,
+ int src_reg, int ctx_off,
+ struct bpf_insn *insn_buf,
+ struct bpf_prog *prog)
+{
+ struct bpf_insn *insn = insn_buf;
+
+ switch (ctx_off) {
+ case offsetof(struct bpf_perf_event_data, sample_period):
+ BUILD_BUG_ON(FIELD_SIZEOF(struct perf_sample_data, period) != sizeof(u64));
+
+ *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
+ data), dst_reg, src_reg,
+ offsetof(struct bpf_perf_event_data_kern, data));
+ *insn++ = BPF_LDX_MEM(BPF_DW, dst_reg, dst_reg,
+ offsetof(struct perf_sample_data, period));
+ break;
+ default:
+ *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
+ regs), dst_reg, src_reg,
+ offsetof(struct bpf_perf_event_data_kern, regs));
+ *insn++ = BPF_LDX_MEM(BPF_SIZEOF(long), dst_reg, dst_reg, ctx_off);
+ break;
+ }
+
+ return insn - insn_buf;
+}
+
+static const struct bpf_verifier_ops perf_event_prog_ops = {
+ .get_func_proto = tp_prog_func_proto,
+ .is_valid_access = pe_prog_is_valid_access,
+ .convert_ctx_access = pe_prog_convert_ctx_access,
+};
+
+static struct bpf_prog_type_list perf_event_tl = {
+ .ops = &perf_event_prog_ops,
+ .type = BPF_PROG_TYPE_PERF_EVENT,
+};
+
static int __init register_kprobe_prog_ops(void)
{
bpf_register_prog_type(&kprobe_tl);
bpf_register_prog_type(&tracepoint_tl);
+ bpf_register_prog_type(&perf_event_tl);
return 0;
}
late_initcall(register_kprobe_prog_ops);
projects / cascardo / linux.git / blobdiff