xref: /linux/tools/perf/arch/s390/util/machine.c (revision 8a922b7728a93d837954315c98b84f6b78de0c4f)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <inttypes.h>
3 #include <unistd.h>
4 #include <stdio.h>
5 #include <string.h>
6 #include <internal/lib.h> // page_size
7 #include "machine.h"
8 #include "api/fs/fs.h"
9 #include "debug.h"
10 #include "symbol.h"
11 
12 int arch__fix_module_text_start(u64 *start, u64 *size, const char *name)
13 {
14 	u64 m_start = *start;
15 	char path[PATH_MAX];
16 
17 	snprintf(path, PATH_MAX, "module/%.*s/sections/.text",
18 				(int)strlen(name) - 2, name + 1);
19 	if (sysfs__read_ull(path, (unsigned long long *)start) < 0) {
20 		pr_debug2("Using module %s start:%#lx\n", path, m_start);
21 		*start = m_start;
22 	} else {
23 		/* Successful read of the modules segment text start address.
24 		 * Calculate difference between module start address
25 		 * in memory and module text segment start address.
26 		 * For example module load address is 0x3ff8011b000
27 		 * (from /proc/modules) and module text segment start
28 		 * address is 0x3ff8011b870 (from file above).
29 		 *
30 		 * Adjust the module size and subtract the GOT table
31 		 * size located at the beginning of the module.
32 		 */
33 		*size -= (*start - m_start);
34 	}
35 
36 	return 0;
37 }
38