[PATCH iproute2-next v2] lib/fs: fix issue when {name,open}_to_handle_at() is not implemented
From: Heiko Thiery <hidden>
Date: 2021-04-30 06:27:16
Also in:
lkml
Subsystem:
library code, the rest · Maintainers:
Andrew Morton, Linus Torvalds
With commit d5e6ee0dac64b64e the usage of functions name_to_handle_at() and open_by_handle_at() are introduced. But these function are not available e.g. in uclibc-ng < 1.0.35. To have a backward compatibility check for the availability in the configure script and in case of absence do a direct syscall. Signed-off-by: Heiko Thiery <redacted> --- v2: - small correction to subject - removed IP_CONFIG_HANDLE_AT:=y option since it is not required - fix indentation in check function - removed empty lines (thanks to Petr Vorel) - add #define _GNU_SOURCE in check (thanks to Petr Vorel) - check only for name_to_handle_at (thanks to Peter Vorel) configure | 28 ++++++++++++++++++++++++++++ lib/fs.c | 21 +++++++++++++++++++++ 2 files changed, 49 insertions(+)
diff --git a/configure b/configure
index 2c363d3b..179eae08 100755
--- a/configure
+++ b/configure@@ -202,6 +202,31 @@ EOF rm -f $TMPDIR/setnstest.c $TMPDIR/setnstest } +check_name_to_handle_at() +{ + cat >$TMPDIR/name_to_handle_at_test.c <<EOF +#define _GNU_SOURCE +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +int main(int argc, char **argv) +{ + struct file_handle *fhp; + int mount_id, flags, dirfd; + char *pathname; + name_to_handle_at(dirfd, pathname, fhp, &mount_id, flags); + return 0; +} +EOF + if $CC -I$INCLUDE -o $TMPDIR/name_to_handle_at_test $TMPDIR/name_to_handle_at_test.c >/dev/null 2>&1; then + echo "yes" + echo "CFLAGS += -DHAVE_HANDLE_AT" >>$CONFIG + else + echo "no" + fi + rm -f $TMPDIR/name_to_handle_at_test.c $TMPDIR/name_to_handle_at_test +} + check_ipset() { cat >$TMPDIR/ipsettest.c <<EOF
@@ -492,6 +517,9 @@ fi echo -n "libc has setns: " check_setns +echo -n "libc has name_to_handle_at: " +check_name_to_handle_at + echo -n "SELinux support: " check_selinux
diff --git a/lib/fs.c b/lib/fs.c
index ee0b130b..feb12864 100644
--- a/lib/fs.c
+++ b/lib/fs.c@@ -30,6 +30,27 @@ /* if not already mounted cgroup2 is mounted here for iproute2's use */ #define MNT_CGRP2_PATH "/var/run/cgroup2" + +#ifndef defined HAVE_HANDLE_AT +struct file_handle { + unsigned handle_bytes; + int handle_type; + unsigned char f_handle[]; +}; + +int name_to_handle_at(int dirfd, const char *pathname, + struct file_handle *handle, int *mount_id, int flags) +{ + return syscall(name_to_handle_at, 5, dirfd, pathname, handle, + mount_id, flags); +} + +int open_by_handle_at(int mount_fd, struct file_handle *handle, int flags) +{ + return syscall(open_by_handle_at, 3, mount_fd, handle, flags); +} +#endif + /* return mount path of first occurrence of given fstype */ static char *find_fs_mount(const char *fs_to_find) {
--
2.30.0