[PATCH 1/4] selftests: vm: Fix mlock2-tests for 32-bit architectures

From: Thierry Reding
Date: Fri Aug 07 2015 - 09:45:11 EST


From: Thierry Reding <treding@xxxxxxxxxx>

According to Documentation/vm/pagemap.txt, the /proc/pid/pagemap file
contains one 64-bit value for each virtual page. The test code relies
on the size of unsigned long being 64-bit, which breaks the test when
run on 32-bit architectures. Use a uint64_t to store values read from
the file instead, so that it works irrespective of the architecture's
word size.

Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
---
tools/testing/selftests/vm/mlock2-tests.c | 33 +++++++++++++------------------
1 file changed, 14 insertions(+), 19 deletions(-)

diff --git a/tools/testing/selftests/vm/mlock2-tests.c b/tools/testing/selftests/vm/mlock2-tests.c
index c49122bebf3c..11c38e96f336 100644
--- a/tools/testing/selftests/vm/mlock2-tests.c
+++ b/tools/testing/selftests/vm/mlock2-tests.c
@@ -1,4 +1,5 @@
#include <sys/mman.h>
+#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
@@ -82,10 +83,10 @@ out:
return ret;
}

-static unsigned long get_pageflags(unsigned long addr)
+static uint64_t get_pageflags(unsigned long addr)
{
FILE *file;
- unsigned long pfn;
+ uint64_t pfn;
unsigned long offset;

file = fopen("/proc/self/pagemap", "r");
@@ -94,13 +95,14 @@ static unsigned long get_pageflags(unsigned long addr)
_exit(1);
}

- offset = addr / getpagesize() * sizeof(unsigned long);
+ offset = addr / getpagesize() * sizeof(pfn);
+
if (fseek(file, offset, SEEK_SET)) {
perror("fseek pagemap");
_exit(1);
}

- if (fread(&pfn, sizeof(unsigned long), 1, file) != 1) {
+ if (fread(&pfn, sizeof(pfn), 1, file) != 1) {
perror("fread pagemap");
_exit(1);
}
@@ -111,7 +113,7 @@ static unsigned long get_pageflags(unsigned long addr)

static unsigned long get_kpageflags(unsigned long pfn)
{
- unsigned long flags;
+ uint64_t flags;
FILE *file;

file = fopen("/proc/kpageflags", "r");
@@ -120,12 +122,12 @@ static unsigned long get_kpageflags(unsigned long pfn)
_exit(1);
}

- if (fseek(file, pfn * sizeof(unsigned long), SEEK_SET)) {
+ if (fseek(file, pfn * sizeof(flags), SEEK_SET)) {
perror("fseek kpageflags");
_exit(1);
}

- if (fread(&flags, sizeof(unsigned long), 1, file) != 1) {
+ if (fread(&flags, sizeof(flags), 1, file) != 1) {
perror("fread kpageflags");
_exit(1);
}
@@ -211,9 +213,8 @@ out:

static int lock_check(char *map)
{
- unsigned long page1_flags;
- unsigned long page2_flags;
unsigned long page_size = getpagesize();
+ uint64_t page1_flags, page2_flags;

page1_flags = get_pageflags((unsigned long)map);
page2_flags = get_pageflags((unsigned long)map + page_size);
@@ -246,9 +247,8 @@ static int lock_check(char *map)

static int unlock_lock_check(char *map)
{
- unsigned long page1_flags;
- unsigned long page2_flags;
unsigned long page_size = getpagesize();
+ uint64_t page1_flags, page2_flags;

page1_flags = get_pageflags((unsigned long)map);
page2_flags = get_pageflags((unsigned long)map + page_size);
@@ -310,9 +310,8 @@ out:

static int onfault_check(char *map)
{
- unsigned long page1_flags;
- unsigned long page2_flags;
unsigned long page_size = getpagesize();
+ uint64_t page1_flags, page2_flags;

page1_flags = get_pageflags((unsigned long)map);
page2_flags = get_pageflags((unsigned long)map + page_size);
@@ -355,9 +354,8 @@ static int onfault_check(char *map)

static int unlock_onfault_check(char *map)
{
- unsigned long page1_flags;
- unsigned long page2_flags;
unsigned long page_size = getpagesize();
+ uint64_t page1_flags;

page1_flags = get_pageflags((unsigned long)map);
page1_flags = get_kpageflags(page1_flags & PFN_MASK);
@@ -422,9 +420,8 @@ static int test_lock_onfault_of_present()
{
char *map;
int ret = 1;
- unsigned long page1_flags;
- unsigned long page2_flags;
unsigned long page_size = getpagesize();
+ uint64_t page1_flags, page2_flags;

map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
@@ -471,8 +468,6 @@ static int test_munlockall()
{
char *map;
int ret = 1;
- unsigned long page1_flags;
- unsigned long page2_flags;
unsigned long page_size = getpagesize();

map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,
--
2.4.5

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