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/* SPDX-License-Identifier: LGPL-2.1-or-later */
#pragma once
#include <fcntl.h>
#include <stdbool.h>
#include <stddef.h>
#include <sys/types.h>
/* The limit used for /dev itself. 4MB should be enough since device nodes and symlinks don't
* consume any space and udev isn't supposed to create regular file either. There's no limit on the
* max number of inodes since such limit is hard to guess especially on large storage array
* systems. */
#define TMPFS_LIMITS_DEV ",size=4m"
/* The limit used for /dev in private namespaces. 4MB for contents of regular files. The number of
* inodes should be relatively low in private namespaces but for now use a 64k limit. */
#define TMPFS_LIMITS_PRIVATE_DEV ",size=4m,nr_inodes=64k"
/* Very little, if any use expected */
#define TMPFS_LIMITS_EMPTY_OR_ALMOST ",size=4m,nr_inodes=1k"
#define TMPFS_LIMITS_SYS TMPFS_LIMITS_EMPTY_OR_ALMOST
#define TMPFS_LIMITS_SYS_FS_CGROUP TMPFS_LIMITS_EMPTY_OR_ALMOST
/* On an extremely small device with only 256MB of RAM, 20% of RAM should be enough for the re-execution of
* PID1 because 16MB of free space is required. */
#define TMPFS_LIMITS_RUN ",size=20%,nr_inodes=800k"
/* The limit used for various nested tmpfs mounts, in particular for guests started by systemd-nspawn.
* 10% of RAM (using 16GB of RAM as a baseline) translates to 400k inodes (assuming 4k each) and 25%
* translates to 1M inodes.
* (On the host, /tmp is configured through a .mount unit file.) */
#define NESTED_TMPFS_LIMITS ",size=10%,nr_inodes=400k"
/* More space for volatile root and /var */
#define TMPFS_LIMITS_VAR ",size=25%,nr_inodes=1m"
#define TMPFS_LIMITS_ROOTFS TMPFS_LIMITS_VAR
#define TMPFS_LIMITS_VOLATILE_STATE TMPFS_LIMITS_VAR
bool is_name_to_handle_at_fatal_error(int err);
int name_to_handle_at_loop(int fd, const char *path, struct file_handle **ret_handle, int *ret_mnt_id, int flags);
int name_to_handle_at_try_fid(int fd, const char *path, struct file_handle **ret_handle, int *ret_mnt_id, int flags);
bool file_handle_equal(const struct file_handle *a, const struct file_handle *b);
int path_get_mnt_id_at_fallback(int dir_fd, const char *path, int *ret);
int path_get_mnt_id_at(int dir_fd, const char *path, int *ret);
static inline int path_get_mnt_id(const char *path, int *ret) {
return path_get_mnt_id_at(AT_FDCWD, path, ret);
}
int fd_is_mount_point(int fd, const char *filename, int flags);
int path_is_mount_point_full(const char *path, const char *root, int flags);
static inline int path_is_mount_point(const char *path) {
return path_is_mount_point_full(path, NULL, 0);
}
bool fstype_is_network(const char *fstype);
bool fstype_needs_quota(const char *fstype);
bool fstype_is_api_vfs(const char *fstype);
bool fstype_is_blockdev_backed(const char *fstype);
bool fstype_is_ro(const char *fsype);
bool fstype_can_discard(const char *fstype);
bool fstype_can_uid_gid(const char *fstype);
bool fstype_can_umask(const char *fstype);
const char* fstype_norecovery_option(const char *fstype);
int dev_is_devtmpfs(void);
int mount_nofollow(
const char *source,
const char *target,
const char *filesystemtype,
unsigned long mountflags,
const void *data);
const char* mount_propagation_flag_to_string(unsigned long flags);
int mount_propagation_flag_from_string(const char *name, unsigned long *ret);
bool mount_propagation_flag_is_valid(unsigned long flag);
bool mount_new_api_supported(void);
unsigned long ms_nosymfollow_supported(void);
int mount_option_supported(const char *fstype, const char *key, const char *value);
bool path_below_api_vfs(const char *p);
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