]>
Commit | Line | Data |
---|---|---|
53e1b683 | 1 | /* SPDX-License-Identifier: LGPL-2.1+ */ |
91214a37 LP |
2 | |
3 | #include <sys/mount.h> | |
4 | ||
5 | #include "alloc-util.h" | |
6 | #include "fs-util.h" | |
5e332028 | 7 | #include "main-func.h" |
91214a37 LP |
8 | #include "mkdir.h" |
9 | #include "mount-util.h" | |
049af8ad | 10 | #include "mountpoint-util.h" |
5e332028 | 11 | #include "path-util.h" |
91214a37 | 12 | #include "stat-util.h" |
91214a37 | 13 | #include "string-util.h" |
5e332028 | 14 | #include "volatile-util.h" |
91214a37 LP |
15 | |
16 | static int make_volatile(const char *path) { | |
17 | _cleanup_free_ char *old_usr = NULL; | |
18 | int r; | |
19 | ||
20 | r = path_is_mount_point(path, NULL, AT_SYMLINK_FOLLOW); | |
21 | if (r < 0) | |
22 | return log_error_errno(r, "Couldn't determine whether %s is a mount point: %m", path); | |
baaa35ad ZJS |
23 | if (r == 0) |
24 | return log_error_errno(SYNTHETIC_ERRNO(EINVAL), | |
25 | "%s is not a mount point.", path); | |
91214a37 LP |
26 | |
27 | r = path_is_temporary_fs(path); | |
28 | if (r < 0) | |
29 | return log_error_errno(r, "Couldn't determine whether %s is a temporary file system: %m", path); | |
30 | if (r > 0) { | |
31 | log_info("%s already is a temporary file system.", path); | |
32 | return 0; | |
33 | } | |
34 | ||
35 | r = chase_symlinks("/usr", path, CHASE_PREFIX_ROOT, &old_usr); | |
36 | if (r < 0) | |
37 | return log_error_errno(r, "/usr not available in old root: %m"); | |
38 | ||
39 | r = mkdir_p("/run/systemd/volatile-sysroot", 0700); | |
40 | if (r < 0) | |
41 | return log_error_errno(r, "Couldn't generate volatile sysroot directory: %m"); | |
42 | ||
43 | r = mount_verbose(LOG_ERR, "tmpfs", "/run/systemd/volatile-sysroot", "tmpfs", MS_STRICTATIME, "mode=755"); | |
44 | if (r < 0) | |
45 | goto finish_rmdir; | |
46 | ||
47 | if (mkdir("/run/systemd/volatile-sysroot/usr", 0755) < 0) { | |
48 | r = -errno; | |
49 | goto finish_umount; | |
50 | } | |
51 | ||
52 | r = mount_verbose(LOG_ERR, old_usr, "/run/systemd/volatile-sysroot/usr", NULL, MS_BIND|MS_REC, NULL); | |
53 | if (r < 0) | |
54 | goto finish_umount; | |
55 | ||
56 | r = bind_remount_recursive("/run/systemd/volatile-sysroot/usr", true, NULL); | |
57 | if (r < 0) | |
58 | goto finish_umount; | |
59 | ||
60 | r = umount_recursive(path, 0); | |
61 | if (r < 0) { | |
62 | log_error_errno(r, "Failed to unmount %s: %m", path); | |
63 | goto finish_umount; | |
64 | } | |
65 | ||
66 | if (mount(NULL, "/", NULL, MS_SLAVE|MS_REC, NULL) < 0) | |
67 | log_warning_errno(errno, "Failed to remount %s MS_SLAVE|MS_REC: %m", path); | |
68 | ||
69 | r = mount_verbose(LOG_ERR, "/run/systemd/volatile-sysroot", path, NULL, MS_MOVE, NULL); | |
70 | ||
71 | finish_umount: | |
72 | (void) umount_recursive("/run/systemd/volatile-sysroot", 0); | |
73 | ||
74 | finish_rmdir: | |
75 | (void) rmdir("/run/systemd/volatile-sysroot"); | |
76 | ||
77 | return r; | |
78 | } | |
79 | ||
51e23786 | 80 | static int run(int argc, char *argv[]) { |
91214a37 LP |
81 | VolatileMode m = _VOLATILE_MODE_INVALID; |
82 | const char *path; | |
83 | int r; | |
84 | ||
6bf3c61c | 85 | log_setup_service(); |
91214a37 | 86 | |
baaa35ad ZJS |
87 | if (argc > 3) |
88 | return log_error_errno(SYNTHETIC_ERRNO(EINVAL), | |
89 | "Too many arguments. Expected directory and mode."); | |
91214a37 LP |
90 | |
91 | r = query_volatile_mode(&m); | |
51e23786 ZJS |
92 | if (r < 0) |
93 | return log_error_errno(r, "Failed to determine volatile mode from kernel command line."); | |
91214a37 LP |
94 | if (r == 0 && argc >= 2) { |
95 | /* The kernel command line always wins. However if nothing was set there, the argument passed here wins instead. */ | |
96 | m = volatile_mode_from_string(argv[1]); | |
97 | if (m < 0) { | |
98 | log_error("Couldn't parse volatile mode: %s", argv[1]); | |
99 | r = -EINVAL; | |
91214a37 LP |
100 | } |
101 | } | |
102 | ||
103 | if (argc < 3) | |
104 | path = "/sysroot"; | |
105 | else { | |
106 | path = argv[2]; | |
107 | ||
baaa35ad ZJS |
108 | if (isempty(path)) |
109 | return log_error_errno(SYNTHETIC_ERRNO(EINVAL), | |
110 | "Directory name cannot be empty."); | |
111 | if (!path_is_absolute(path)) | |
112 | return log_error_errno(SYNTHETIC_ERRNO(EINVAL), | |
113 | "Directory must be specified as absolute path."); | |
114 | if (path_equal(path, "/")) | |
115 | return log_error_errno(SYNTHETIC_ERRNO(EINVAL), | |
116 | "Directory cannot be the root directory."); | |
91214a37 LP |
117 | } |
118 | ||
51e23786 ZJS |
119 | if (m != VOLATILE_YES) |
120 | return 0; | |
91214a37 | 121 | |
51e23786 | 122 | return make_volatile(path); |
91214a37 | 123 | } |
51e23786 ZJS |
124 | |
125 | DEFINE_MAIN_FUNCTION(run); |