1 files changed, 15 insertions, 73 deletions

diff --git a/tools/perf/util/llvm.c b/tools/perf/util/llvm.c
index b71649d616e3..ec41d0f27000 100644
--- a/tools/perf/util/llvm.c
+++ b/tools/perf/util/llvm.c
@@ -87,71 +87,6 @@ static void init_llvm(void)
 	}
 }
 
-struct find_file_offset_data {
-	u64 ip;
-	u64 offset;
-};
-
-/* This will be called for each PHDR in an ELF binary */
-static int find_file_offset(u64 start, u64 len, u64 pgoff, void *arg)
-{
-	struct find_file_offset_data *data = arg;
-
-	if (start <= data->ip && data->ip < start + len) {
-		data->offset = pgoff + data->ip - start;
-		return 1;
-	}
-	return 0;
-}
-
-static u8 *
-read_symbol(const char *filename, struct map *map, struct symbol *sym,
-	    u64 *len, bool *is_64bit)
-{
-	struct dso *dso = map__dso(map);
-	struct nscookie nsc;
-	u64 start = map__rip_2objdump(map, sym->start);
-	u64 end = map__rip_2objdump(map, sym->end);
-	int fd, count;
-	u8 *buf = NULL;
-	struct find_file_offset_data data = {
-		.ip = start,
-	};
-
-	*is_64bit = false;
-
-	nsinfo__mountns_enter(dso__nsinfo(dso), &nsc);
-	fd = open(filename, O_RDONLY);
-	nsinfo__mountns_exit(&nsc);
-	if (fd < 0)
-		return NULL;
-
-	if (file__read_maps(fd, /*exe=*/true, find_file_offset, &data,
-			    is_64bit) == 0)
-		goto err;
-
-	*len = end - start;
-	buf = malloc(*len);
-	if (buf == NULL)
-		goto err;
-
-	count = pread(fd, buf, *len, data.offset);
-	close(fd);
-	fd = -1;
-
-	if ((u64)count != *len)
-		goto err;
-
-	return buf;
-
-err:
-	if (fd >= 0)
-		close(fd);
-	free(buf);
-	return NULL;
-}
-#endif
-
 /*
  * Whenever LLVM wants to resolve an address into a symbol, it calls this
  * callback. We don't ever actually _return_ anything (in particular, because
@@ -160,7 +95,6 @@ err:
  * should add some textual annotation for after the instruction. The caller
  * will use this information to add the actual annotation.
  */
-#ifdef HAVE_LIBLLVM_SUPPORT
 struct symbol_lookup_storage {
 	u64 branch_addr;
 	u64 pcrel_load_addr;
@@ -191,8 +125,11 @@ int symbol__disassemble_llvm(const char *filename, struct symbol *sym,
 	struct map *map = args->ms.map;
 	struct dso *dso = map__dso(map);
 	u64 start = map__rip_2objdump(map, sym->start);
-	u8 *buf;
-	u64 len;
+	/* Malloc-ed buffer containing instructions read from disk. */
+	u8 *code_buf = NULL;
+	/* Pointer to code to be disassembled. */
+	const u8 *buf;
+	u64 buf_len;
 	u64 pc;
 	bool is_64bit;
 	char disasm_buf[2048];
@@ -207,7 +144,8 @@ int symbol__disassemble_llvm(const char *filename, struct symbol *sym,
 	if (args->options->objdump_path)
 		return -1;
 
-	buf = read_symbol(filename, map, sym, &len, &is_64bit);
+	buf = dso__read_symbol(dso, filename, map, sym,
+			       &code_buf, &buf_len, &is_64bit);
 	if (buf == NULL)
 		return -1;
 
@@ -259,14 +197,18 @@ int symbol__disassemble_llvm(const char *filename, struct symbol *sym,
 	annotation_line__add(&dl->al, &notes->src->source);
 
 	pc = start;
-	for (u64 offset = 0; offset < len; ) {
+	for (u64 offset = 0; offset < buf_len; ) {
 		unsigned int ins_len;
 
 		storage.branch_addr = 0;
 		storage.pcrel_load_addr = 0;
 
-		ins_len = LLVMDisasmInstruction(disasm, buf + offset,
-						len - offset, pc,
+		/*
+		 * LLVM's API has the code be disassembled as non-const, cast
+		 * here as we may be disassembling from mapped read-only memory.
+		 */
+		ins_len = LLVMDisasmInstruction(disasm, (u8 *)(buf + offset),
+						buf_len - offset, pc,
 						disasm_buf, sizeof(disasm_buf));
 		if (ins_len == 0)
 			goto err;
@@ -324,7 +266,7 @@ int symbol__disassemble_llvm(const char *filename, struct symbol *sym,
 
 err:
 	LLVMDisasmDispose(disasm);
-	free(buf);
+	free(code_buf);
 	free(line_storage);
 	return ret;
 #else // HAVE_LIBLLVM_SUPPORT