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-rw-r--r--kernel/trace/trace_probe_tmpl.h120
1 files changed, 120 insertions, 0 deletions
diff --git a/kernel/trace/trace_probe_tmpl.h b/kernel/trace/trace_probe_tmpl.h
new file mode 100644
index 000000000000..c8a5272abf01
--- /dev/null
+++ b/kernel/trace/trace_probe_tmpl.h
@@ -0,0 +1,120 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Traceprobe fetch helper inlines
+ */
+
+static nokprobe_inline void
+fetch_store_raw(unsigned long val, struct fetch_insn *code, void *buf)
+{
+ switch (code->size) {
+ case 1:
+ *(u8 *)buf = (u8)val;
+ break;
+ case 2:
+ *(u16 *)buf = (u16)val;
+ break;
+ case 4:
+ *(u32 *)buf = (u32)val;
+ break;
+ case 8:
+ //TBD: 32bit signed
+ *(u64 *)buf = (u64)val;
+ break;
+ default:
+ *(unsigned long *)buf = val;
+ }
+}
+
+static nokprobe_inline void
+fetch_apply_bitfield(struct fetch_insn *code, void *buf)
+{
+ switch (code->basesize) {
+ case 1:
+ *(u8 *)buf <<= code->lshift;
+ *(u8 *)buf >>= code->rshift;
+ break;
+ case 2:
+ *(u16 *)buf <<= code->lshift;
+ *(u16 *)buf >>= code->rshift;
+ break;
+ case 4:
+ *(u32 *)buf <<= code->lshift;
+ *(u32 *)buf >>= code->rshift;
+ break;
+ case 8:
+ *(u64 *)buf <<= code->lshift;
+ *(u64 *)buf >>= code->rshift;
+ break;
+ }
+}
+
+/* Define this for each callsite */
+static int
+process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs,
+ void *dest, bool pre);
+
+/* Sum up total data length for dynamic arraies (strings) */
+static nokprobe_inline int
+__get_data_size(struct trace_probe *tp, struct pt_regs *regs)
+{
+ struct probe_arg *arg;
+ int i, ret = 0;
+ u32 len;
+
+ for (i = 0; i < tp->nr_args; i++) {
+ arg = tp->args + i;
+ if (unlikely(arg->dynamic)) {
+ process_fetch_insn(arg->code, regs, &len, true);
+ ret += len;
+ }
+ }
+
+ return ret;
+}
+
+/* Store the value of each argument */
+static nokprobe_inline void
+store_trace_args(int ent_size, struct trace_probe *tp, struct pt_regs *regs,
+ u8 *data, int maxlen)
+{
+ struct probe_arg *arg;
+ u32 end = tp->size;
+ u32 *dl; /* Data (relative) location */
+ int i;
+
+ for (i = 0; i < tp->nr_args; i++) {
+ arg = tp->args + i;
+ if (unlikely(arg->dynamic)) {
+ /*
+ * First, we set the relative location and
+ * maximum data length to *dl
+ */
+ dl = (u32 *)(data + arg->offset);
+ *dl = make_data_rloc(maxlen, end - arg->offset);
+ /* Then try to fetch string or dynamic array data */
+ process_fetch_insn(arg->code, regs, dl, false);
+ /* Reduce maximum length */
+ end += get_rloc_len(*dl);
+ maxlen -= get_rloc_len(*dl);
+ /* Trick here, convert data_rloc to data_loc */
+ *dl = convert_rloc_to_loc(*dl, ent_size + arg->offset);
+ } else
+ /* Just fetching data normally */
+ process_fetch_insn(arg->code, regs, data + arg->offset,
+ false);
+ }
+}
+
+static inline int
+print_probe_args(struct trace_seq *s, struct probe_arg *args, int nr_args,
+ u8 *data, void *field)
+{
+ int i;
+
+ for (i = 0; i < nr_args; i++) {
+ trace_seq_printf(s, " %s=", args[i].name);
+ if (!args[i].type->print(s, data + args[i].offset, field))
+ return -ENOMEM;
+ }
+ return 0;
+}