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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /kernel/trace/trace_probe_tmpl.h | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'kernel/trace/trace_probe_tmpl.h')
-rw-r--r-- | kernel/trace/trace_probe_tmpl.h | 275 |
1 files changed, 275 insertions, 0 deletions
diff --git a/kernel/trace/trace_probe_tmpl.h b/kernel/trace/trace_probe_tmpl.h new file mode 100644 index 0000000000..3935b347f8 --- /dev/null +++ b/kernel/trace/trace_probe_tmpl.h @@ -0,0 +1,275 @@ +/* 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; + } +} + +/* + * These functions must be defined for each callsite. + * Return consumed dynamic data size (>= 0), or error (< 0). + * If dest is NULL, don't store result and return required dynamic data size. + */ +static int +process_fetch_insn(struct fetch_insn *code, void *rec, + void *dest, void *base); +static nokprobe_inline int fetch_store_strlen(unsigned long addr); +static nokprobe_inline int +fetch_store_string(unsigned long addr, void *dest, void *base); +static nokprobe_inline int fetch_store_strlen_user(unsigned long addr); +static nokprobe_inline int +fetch_store_string_user(unsigned long addr, void *dest, void *base); +static nokprobe_inline int +probe_mem_read(void *dest, void *src, size_t size); +static nokprobe_inline int +probe_mem_read_user(void *dest, void *src, size_t size); + +static nokprobe_inline int +fetch_store_symstrlen(unsigned long addr) +{ + char namebuf[KSYM_SYMBOL_LEN]; + int ret; + + ret = sprint_symbol(namebuf, addr); + if (ret < 0) + return 0; + + return ret + 1; +} + +/* + * Fetch a null-terminated symbol string + offset. Caller MUST set *(u32 *)buf + * with max length and relative data location. + */ +static nokprobe_inline int +fetch_store_symstring(unsigned long addr, void *dest, void *base) +{ + int maxlen = get_loc_len(*(u32 *)dest); + void *__dest; + + if (unlikely(!maxlen)) + return -ENOMEM; + + __dest = get_loc_data(dest, base); + + return sprint_symbol(__dest, addr); +} + +/* common part of process_fetch_insn*/ +static nokprobe_inline int +process_common_fetch_insn(struct fetch_insn *code, unsigned long *val) +{ + switch (code->op) { + case FETCH_OP_IMM: + *val = code->immediate; + break; + case FETCH_OP_COMM: + *val = (unsigned long)current->comm; + break; + case FETCH_OP_DATA: + *val = (unsigned long)code->data; + break; + default: + return -EILSEQ; + } + return 0; +} + +/* From the 2nd stage, routine is same */ +static nokprobe_inline int +process_fetch_insn_bottom(struct fetch_insn *code, unsigned long val, + void *dest, void *base) +{ + struct fetch_insn *s3 = NULL; + int total = 0, ret = 0, i = 0; + u32 loc = 0; + unsigned long lval = val; + +stage2: + /* 2nd stage: dereference memory if needed */ + do { + if (code->op == FETCH_OP_DEREF) { + lval = val; + ret = probe_mem_read(&val, (void *)val + code->offset, + sizeof(val)); + } else if (code->op == FETCH_OP_UDEREF) { + lval = val; + ret = probe_mem_read_user(&val, + (void *)val + code->offset, sizeof(val)); + } else + break; + if (ret) + return ret; + code++; + } while (1); + + s3 = code; +stage3: + /* 3rd stage: store value to buffer */ + if (unlikely(!dest)) { + switch (code->op) { + case FETCH_OP_ST_STRING: + ret = fetch_store_strlen(val + code->offset); + code++; + goto array; + case FETCH_OP_ST_USTRING: + ret = fetch_store_strlen_user(val + code->offset); + code++; + goto array; + case FETCH_OP_ST_SYMSTR: + ret = fetch_store_symstrlen(val + code->offset); + code++; + goto array; + default: + return -EILSEQ; + } + } + + switch (code->op) { + case FETCH_OP_ST_RAW: + fetch_store_raw(val, code, dest); + break; + case FETCH_OP_ST_MEM: + probe_mem_read(dest, (void *)val + code->offset, code->size); + break; + case FETCH_OP_ST_UMEM: + probe_mem_read_user(dest, (void *)val + code->offset, code->size); + break; + case FETCH_OP_ST_STRING: + loc = *(u32 *)dest; + ret = fetch_store_string(val + code->offset, dest, base); + break; + case FETCH_OP_ST_USTRING: + loc = *(u32 *)dest; + ret = fetch_store_string_user(val + code->offset, dest, base); + break; + case FETCH_OP_ST_SYMSTR: + loc = *(u32 *)dest; + ret = fetch_store_symstring(val + code->offset, dest, base); + break; + default: + return -EILSEQ; + } + code++; + + /* 4th stage: modify stored value if needed */ + if (code->op == FETCH_OP_MOD_BF) { + fetch_apply_bitfield(code, dest); + code++; + } + +array: + /* the last stage: Loop on array */ + if (code->op == FETCH_OP_LP_ARRAY) { + if (ret < 0) + ret = 0; + total += ret; + if (++i < code->param) { + code = s3; + if (s3->op != FETCH_OP_ST_STRING && + s3->op != FETCH_OP_ST_USTRING) { + dest += s3->size; + val += s3->size; + goto stage3; + } + code--; + val = lval + sizeof(char *); + if (dest) { + dest += sizeof(u32); + *(u32 *)dest = update_data_loc(loc, ret); + } + goto stage2; + } + code++; + ret = total; + } + + return code->op == FETCH_OP_END ? ret : -EILSEQ; +} + +/* Sum up total data length for dynamic arrays (strings) */ +static nokprobe_inline int +__get_data_size(struct trace_probe *tp, struct pt_regs *regs) +{ + struct probe_arg *arg; + int i, len, ret = 0; + + for (i = 0; i < tp->nr_args; i++) { + arg = tp->args + i; + if (unlikely(arg->dynamic)) { + len = process_fetch_insn(arg->code, regs, NULL, NULL); + if (len > 0) + ret += len; + } + } + + return ret; +} + +/* Store the value of each argument */ +static nokprobe_inline void +store_trace_args(void *data, struct trace_probe *tp, void *rec, + int header_size, int maxlen) +{ + struct probe_arg *arg; + void *base = data - header_size; + void *dyndata = data + tp->size; + u32 *dl; /* Data location */ + int ret, i; + + for (i = 0; i < tp->nr_args; i++) { + arg = tp->args + i; + dl = data + arg->offset; + /* Point the dynamic data area if needed */ + if (unlikely(arg->dynamic)) + *dl = make_data_loc(maxlen, dyndata - base); + ret = process_fetch_insn(arg->code, rec, dl, base); + if (arg->dynamic && likely(ret > 0)) { + dyndata += ret; + maxlen -= ret; + } + } +} |