[PATCH -next] samples/vfs/mountinfo: Use __u64 instead of uint64_t

From: Geert Uytterhoeven
Date: Mon Jan 06 2025 - 08:48:18 EST


On 32-bit (e.g. arm32, m68k):

samples/vfs/mountinfo.c: In function ‘dump_mountinfo’:
samples/vfs/mountinfo.c:145:29: warning: format ‘%lx’ expects argument of type ‘long unsigned int’, but argument 2 has type ‘uint64_t’ {aka ‘long long unsigned int’} [-Wformat=]
145 | printf("0x%lx 0x%lx 0x%llx ", mnt_ns_id, mnt_id, buf->mnt_parent_id);
| ~~^ ~~~~~~~~~
| | |
| long unsigned int uint64_t {aka long long unsigned int}
| %llx
samples/vfs/mountinfo.c:145:35: warning: format ‘%lx’ expects argument of type ‘long unsigned int’, but argument 3 has type ‘uint64_t’ {aka ‘long long unsigned int’} [-Wformat=]
145 | printf("0x%lx 0x%lx 0x%llx ", mnt_ns_id, mnt_id, buf->mnt_parent_id);
| ~~^ ~~~~~~
| | |
| long unsigned int uint64_t {aka long long unsigned int}
| %llx

Just using "%llx" instead of "%lx" is not sufficient, as uint64_t is
"long unsigned int" on some 64-bit platforms like arm64. Hence also
replace "uint64_t" by "__u64", which matches what most other samples
are already using.

Fixes: d95e49bf8bcdc7c1 ("samples: add a mountinfo program to demonstrate statmount()/listmount()")
Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
---
Feel free to fold into the original commit.

Alternatively, you can use PRIx64, which is used by tools/, but not by
any of the current samples.
---
samples/vfs/mountinfo.c | 35 +++++++++++++++++------------------
1 file changed, 17 insertions(+), 18 deletions(-)

diff --git a/samples/vfs/mountinfo.c b/samples/vfs/mountinfo.c
index 2b17d244d321ee75..f47c035cc339544e 100644
--- a/samples/vfs/mountinfo.c
+++ b/samples/vfs/mountinfo.c
@@ -32,9 +32,9 @@ static bool ext_format;
* There are no bindings in glibc for listmount() and statmount() (yet),
* make our own here.
*/
-static int statmount(uint64_t mnt_id, uint64_t mnt_ns_id, uint64_t mask,
- struct statmount *buf, size_t bufsize,
- unsigned int flags)
+static int statmount(__u64 mnt_id, __u64 mnt_ns_id, __u64 mask,
+ struct statmount *buf, size_t bufsize,
+ unsigned int flags)
{
struct mnt_id_req req = {
.size = MNT_ID_REQ_SIZE_VER0,
@@ -50,9 +50,8 @@ static int statmount(uint64_t mnt_id, uint64_t mnt_ns_id, uint64_t mask,
return syscall(__NR_statmount, &req, buf, bufsize, flags);
}

-static ssize_t listmount(uint64_t mnt_id, uint64_t mnt_ns_id,
- uint64_t last_mnt_id, uint64_t list[], size_t num,
- unsigned int flags)
+static ssize_t listmount(__u64 mnt_id, __u64 mnt_ns_id, __u64 last_mnt_id,
+ __u64 list[], size_t num, unsigned int flags)
{
struct mnt_id_req req = {
.size = MNT_ID_REQ_SIZE_VER0,
@@ -68,7 +67,7 @@ static ssize_t listmount(uint64_t mnt_id, uint64_t mnt_ns_id,
return syscall(__NR_listmount, &req, list, num, flags);
}

-static void show_mnt_attrs(uint64_t flags)
+static void show_mnt_attrs(__u64 flags)
{
printf("%s", flags & MOUNT_ATTR_RDONLY ? "ro" : "rw");

@@ -112,7 +111,7 @@ static void show_propagation(struct statmount *sm)
printf(" unbindable");
}

-static void show_sb_flags(uint64_t flags)
+static void show_sb_flags(__u64 flags)
{
printf("%s", flags & MS_RDONLY ? "ro" : "rw");
if (flags & MS_SYNCHRONOUS)
@@ -125,15 +124,15 @@ static void show_sb_flags(uint64_t flags)
printf(",lazytime");
}

-static int dump_mountinfo(uint64_t mnt_id, uint64_t mnt_ns_id)
+static int dump_mountinfo(__u64 mnt_id, __u64 mnt_ns_id)
{
int ret;
struct statmount *buf = alloca(STATMOUNT_BUFSIZE);
- const uint64_t mask = STATMOUNT_SB_BASIC | STATMOUNT_MNT_BASIC |
- STATMOUNT_PROPAGATE_FROM | STATMOUNT_FS_TYPE |
- STATMOUNT_MNT_ROOT | STATMOUNT_MNT_POINT |
- STATMOUNT_MNT_OPTS | STATMOUNT_FS_SUBTYPE |
- STATMOUNT_SB_SOURCE;
+ const __u64 mask = STATMOUNT_SB_BASIC | STATMOUNT_MNT_BASIC |
+ STATMOUNT_PROPAGATE_FROM | STATMOUNT_FS_TYPE |
+ STATMOUNT_MNT_ROOT | STATMOUNT_MNT_POINT |
+ STATMOUNT_MNT_OPTS | STATMOUNT_FS_SUBTYPE |
+ STATMOUNT_SB_SOURCE;

ret = statmount(mnt_id, mnt_ns_id, mask, buf, STATMOUNT_BUFSIZE, 0);
if (ret < 0) {
@@ -142,7 +141,7 @@ static int dump_mountinfo(uint64_t mnt_id, uint64_t mnt_ns_id)
}

if (ext_format)
- printf("0x%lx 0x%lx 0x%llx ", mnt_ns_id, mnt_id, buf->mnt_parent_id);
+ printf("0x%llx 0x%llx 0x%llx ", mnt_ns_id, mnt_id, buf->mnt_parent_id);

printf("%u %u %u:%u %s %s ", buf->mnt_id_old, buf->mnt_parent_id_old,
buf->sb_dev_major, buf->sb_dev_minor,
@@ -166,10 +165,10 @@ static int dump_mountinfo(uint64_t mnt_id, uint64_t mnt_ns_id)
return 0;
}

-static int dump_mounts(uint64_t mnt_ns_id)
+static int dump_mounts(__u64 mnt_ns_id)
{
- uint64_t mntid[MAXMOUNTS];
- uint64_t last_mnt_id = 0;
+ __u64 mntid[MAXMOUNTS];
+ __u64 last_mnt_id = 0;
ssize_t count;
int i;

--
2.43.0