From 2cb7e0aaedad73b076ea18c6900b0e86c5760d79 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 15:00:47 +0200 Subject: Adding upstream version 247.3. Signed-off-by: Daniel Baumann --- src/shared/mount-util.h | 99 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 99 insertions(+) create mode 100644 src/shared/mount-util.h (limited to 'src/shared/mount-util.h') diff --git a/src/shared/mount-util.h b/src/shared/mount-util.h new file mode 100644 index 0000000..6202008 --- /dev/null +++ b/src/shared/mount-util.h @@ -0,0 +1,99 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +#pragma once + +#include +#include +#include + +#include "errno-util.h" +#include "macro.h" + +/* 4MB for contents of regular files, 64k inodes for directories, symbolic links and device specials, using + * large storage array systems as a baseline */ +#define TMPFS_LIMITS_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 paricular 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 + +int mount_fd(const char *source, int target_fd, const char *filesystemtype, unsigned long mountflags, const void *data); +int mount_nofollow(const char *source, const char *target, const char *filesystemtype, unsigned long mountflags, const void *data); + +int repeat_unmount(const char *path, int flags); +int umount_recursive(const char *target, int flags); +int bind_remount_recursive(const char *prefix, unsigned long new_flags, unsigned long flags_mask, char **deny_list); +int bind_remount_recursive_with_mountinfo(const char *prefix, unsigned long new_flags, unsigned long flags_mask, char **deny_list, FILE *proc_self_mountinfo); +int bind_remount_one_with_mountinfo(const char *path, unsigned long new_flags, unsigned long flags_mask, FILE *proc_self_mountinfo); + +int mount_move_root(const char *path); + +DEFINE_TRIVIAL_CLEANUP_FUNC(FILE*, endmntent); +#define _cleanup_endmntent_ _cleanup_(endmntentp) + +int mount_verbose_full( + int error_log_level, + const char *what, + const char *where, + const char *type, + unsigned long flags, + const char *options, + bool follow_symlink); + +static inline int mount_follow_verbose( + int error_log_level, + const char *what, + const char *where, + const char *type, + unsigned long flags, + const char *options) { + return mount_verbose_full(error_log_level, what, where, type, flags, options, true); +} + +static inline int mount_nofollow_verbose( + int error_log_level, + const char *what, + const char *where, + const char *type, + unsigned long flags, + const char *options) { + return mount_verbose_full(error_log_level, what, where, type, flags, options, false); +} + +int umount_verbose( + int error_log_level, + const char *where, + int flags); + +int mount_option_mangle( + const char *options, + unsigned long mount_flags, + unsigned long *ret_mount_flags, + char **ret_remaining_options); + +int mode_to_inaccessible_node(const char *runtime_dir, mode_t mode, char **dest); + +/* Useful for usage with _cleanup_(), unmounts, removes a directory and frees the pointer */ +static inline char* umount_and_rmdir_and_free(char *p) { + PROTECT_ERRNO; + (void) umount_recursive(p, 0); + (void) rmdir(p); + free(p); + return NULL; +} +DEFINE_TRIVIAL_CLEANUP_FUNC(char*, umount_and_rmdir_and_free); -- cgit v1.2.3