1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
8 #include "alloc-util.h"
9 #include "errno-util.h"
12 /* 4MB for contents of regular files, 64k inodes for directories, symbolic links and device specials, using
13 * large storage array systems as a baseline */
14 #define TMPFS_LIMITS_DEV ",size=4m,nr_inodes=64k"
16 /* Very little, if any use expected */
17 #define TMPFS_LIMITS_EMPTY_OR_ALMOST ",size=4m,nr_inodes=1k"
18 #define TMPFS_LIMITS_SYS TMPFS_LIMITS_EMPTY_OR_ALMOST
19 #define TMPFS_LIMITS_SYS_FS_CGROUP TMPFS_LIMITS_EMPTY_OR_ALMOST
21 /* On an extremely small device with only 256MB of RAM, 20% of RAM should be enough for the re-execution of
22 * PID1 because 16MB of free space is required. */
23 #define TMPFS_LIMITS_RUN ",size=20%,nr_inodes=800k"
25 /* The limit used for various nested tmpfs mounts, in paricular for guests started by systemd-nspawn.
26 * 10% of RAM (using 16GB of RAM as a baseline) translates to 400k inodes (assuming 4k each) and 25%
27 * translates to 1M inodes.
28 * (On the host, /tmp is configured through a .mount unit file.) */
29 #define NESTED_TMPFS_LIMITS ",size=10%,nr_inodes=400k"
31 /* More space for volatile root and /var */
32 #define TMPFS_LIMITS_VAR ",size=25%,nr_inodes=1m"
33 #define TMPFS_LIMITS_ROOTFS TMPFS_LIMITS_VAR
34 #define TMPFS_LIMITS_VOLATILE_STATE TMPFS_LIMITS_VAR
36 int mount_fd(const char *source
, int target_fd
, const char *filesystemtype
, unsigned long mountflags
, const void *data
);
37 int mount_nofollow(const char *source
, const char *target
, const char *filesystemtype
, unsigned long mountflags
, const void *data
);
39 int repeat_unmount(const char *path
, int flags
);
40 int umount_recursive(const char *target
, int flags
);
41 int bind_remount_recursive(const char *prefix
, unsigned long new_flags
, unsigned long flags_mask
, char **deny_list
);
42 int bind_remount_recursive_with_mountinfo(const char *prefix
, unsigned long new_flags
, unsigned long flags_mask
, char **deny_list
, FILE *proc_self_mountinfo
);
43 int bind_remount_one_with_mountinfo(const char *path
, unsigned long new_flags
, unsigned long flags_mask
, FILE *proc_self_mountinfo
);
45 int mount_move_root(const char *path
);
47 DEFINE_TRIVIAL_CLEANUP_FUNC(FILE*, endmntent
);
48 #define _cleanup_endmntent_ _cleanup_(endmntentp)
50 int mount_verbose_full(
59 static inline int mount_follow_verbose(
65 const char *options
) {
66 return mount_verbose_full(error_log_level
, what
, where
, type
, flags
, options
, true);
69 static inline int mount_nofollow_verbose(
75 const char *options
) {
76 return mount_verbose_full(error_log_level
, what
, where
, type
, flags
, options
, false);
84 int mount_option_mangle(
86 unsigned long mount_flags
,
87 unsigned long *ret_mount_flags
,
88 char **ret_remaining_options
);
90 int mode_to_inaccessible_node(const char *runtime_dir
, mode_t mode
, char **dest
);
92 /* Useful for usage with _cleanup_(), unmounts, removes a directory and frees the pointer */
93 static inline char* umount_and_rmdir_and_free(char *p
) {
95 (void) umount_recursive(p
, 0);
99 DEFINE_TRIVIAL_CLEANUP_FUNC(char*, umount_and_rmdir_and_free
);