kernel/linux.git/samples/vfs/mountinfo.c, branch v6.19.11

samples/vfs: use shared header

2025-01-20T11:50:35+00:00

Share some infrastructure between sample programs and fix a build failure that was reported. Reported-by: Sasha Levin Link: https://lore.kernel.org/r/Z42UkSXx0MS9qZ9w@lappy Link: https://qa-reports.linaro.org/lkft/sashal-linus-next/build/v6.13-rc7-511-g109a8e0fa9d6/testrun/26809210/suite/build/test/gcc-8-allyesconfig/log Signed-off-by: Christian Brauner

samples/vfs/mountinfo: Use __u64 instead of uint64_t

2025-01-10T11:08:27+00:00

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 Link: https://lore.kernel.org/r/20250106134802.1019911-1-geert+renesas@glider.be Reviewed-by: Jeff Layton Signed-off-by: Christian Brauner

samples: add a mountinfo program to demonstrate statmount()/listmount()

2025-01-09T15:58:50+00:00

Add a new "mountinfo" sample userland program that demonstrates how to use statmount() and listmount() to get at the same info that /proc/pid/mountinfo provides. The output of the program tries to mimic the mountinfo procfile contents. With the -p flag, it can be pointed at an arbitrary pid to print out info about its mount namespace. With the -r flag it will attempt to walk all of the namespaces under the pid's mount namespace and dump out mount info from all of them. Signed-off-by: Jeff Layton Link: https://lore.kernel.org/r/20241115-statmount-v2-1-cd29aeff9cbb@kernel.org Signed-off-by: Christian Brauner