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Eric Andersenc9f20d92002-12-05 08:41:41 +00001#
2# For a description of the syntax of this configuration file,
3# see scripts/kbuild/config-language.txt.
4#
5
6menu "Linux System Utilities"
7
Eric Andersenc9f20d92002-12-05 08:41:41 +00008config CONFIG_DMESG
9 bool "dmesg"
10 default n
11 help
Eric Andersena0ac4522003-02-27 03:14:04 +000012 dmesg is used to examine or control the kernel ring buffer. When the
13 Linux kernel prints messages to the system log, they are stored in
14 the kernel ring buffer. You can use dmesg to print the kernel's ring
15 buffer, clear the kernel ring buffer, change the size of the kernel
16 ring buffer, and change the priority level at which kernel messages
17 are also logged to the system console. Enable this option if you
18 wish to enable the 'dmesg' utility.
Eric Andersenc9f20d92002-12-05 08:41:41 +000019
20config CONFIG_FBSET
21 bool "fbset"
22 default n
23 help
Eric Andersena0ac4522003-02-27 03:14:04 +000024 fbset is used to show or change the settings of a Linux frame buffer
25 device. The frame buffer device provides a simple and unique
Eric Andersen88c916b2003-10-22 09:58:56 +000026 interface to access a graphics display. Enable this option
27 if you wish to enable the 'fbset' utility.
Eric Andersena0ac4522003-02-27 03:14:04 +000028
Eric Andersenc9f20d92002-12-05 08:41:41 +000029config CONFIG_FEATURE_FBSET_FANCY
Rob Landley2ec922e2006-04-13 23:22:16 +000030 bool "Turn on extra fbset options"
Eric Andersenc9f20d92002-12-05 08:41:41 +000031 default n
32 depends on CONFIG_FBSET
33 help
Eric Andersena0ac4522003-02-27 03:14:04 +000034 This option enables extended fbset options, allowing one to set the
Eric Andersen88c916b2003-10-22 09:58:56 +000035 framebuffer size, color depth, etc. interface to access a graphics
Eric Andersena0ac4522003-02-27 03:14:04 +000036 display. Enable this option if you wish to enable extended fbset
37 options.
Eric Andersenc9f20d92002-12-05 08:41:41 +000038
39config CONFIG_FEATURE_FBSET_READMODE
Rob Landley2ec922e2006-04-13 23:22:16 +000040 bool "Turn on fbset readmode support"
Eric Andersenc9f20d92002-12-05 08:41:41 +000041 default n
42 depends on CONFIG_FBSET
43 help
Eric Andersena0ac4522003-02-27 03:14:04 +000044 This option allows fbset to read the video mode database stored by
45 default as /etc/fb.modes, which can be used to set frame buffer
46 device to pre-defined video modes.
Eric Andersenc9f20d92002-12-05 08:41:41 +000047
48config CONFIG_FDFLUSH
49 bool "fdflush"
50 default n
51 help
Eric Andersen88c916b2003-10-22 09:58:56 +000052 fdflush is only needed when changing media on slightly-broken
Eric Andersena0ac4522003-02-27 03:14:04 +000053 removable media drives. It is used to make Linux believe that a
54 hardware disk-change switch has been actuated, which causes Linux to
55 forget anything it has cached from the previous media. If you have
56 such a slightly-broken drive, you will need to run fdflush every time
57 you change a disk. Most people have working hardware and can safely
Eric Andersen88c916b2003-10-22 09:58:56 +000058 leave this disabled.
Eric Andersenc9f20d92002-12-05 08:41:41 +000059
Eric Andersen01c3d402003-07-05 07:51:31 +000060config CONFIG_FDFORMAT
61 bool "fdformat"
62 default n
63 help
Eric Andersen88c916b2003-10-22 09:58:56 +000064 fdformat is used to low-level format a floppy disk.
Eric Andersen01c3d402003-07-05 07:51:31 +000065
Eric Andersenc9f20d92002-12-05 08:41:41 +000066config CONFIG_FDISK
67 bool "fdisk"
68 default n
69 help
Eric Andersena0ac4522003-02-27 03:14:04 +000070 The fdisk utility is used to divide hard disks into one or more
71 logical disks, which are generally called partitions. This utility
Eric Andersenc7bda1c2004-03-15 08:29:22 +000072 can be used to list and edit the set of partitions or BSD style
Eric Andersena0ac4522003-02-27 03:14:04 +000073 'disk slices' that are defined on a hard drive.
Eric Andersenc9f20d92002-12-05 08:41:41 +000074
Eric Andersen84bdea82004-05-19 10:49:17 +000075config FDISK_SUPPORT_LARGE_DISKS
Rob Landley2ec922e2006-04-13 23:22:16 +000076 bool "support over 4GB disks"
Eric Andersen84bdea82004-05-19 10:49:17 +000077 default y
78 depends on CONFIG_FDISK
Eric Andersen84bdea82004-05-19 10:49:17 +000079 help
80 Enable this option to support large disks > 4GB.
81
Glenn L McGrath4dcc2dd2003-01-04 11:56:06 +000082config CONFIG_FEATURE_FDISK_WRITABLE
Rob Landley2ec922e2006-04-13 23:22:16 +000083 bool "Write support"
Glenn L McGrath4dcc2dd2003-01-04 11:56:06 +000084 default y
85 depends on CONFIG_FDISK
86 help
Eric Andersena0ac4522003-02-27 03:14:04 +000087 Enabling this option allows you to create or change a partition table
88 and write those changes out to disk. If you leave this option
89 disabled, you will only be able to view the partition table.
Glenn L McGrath4dcc2dd2003-01-04 11:56:06 +000090
Eric Andersenc9f20d92002-12-05 08:41:41 +000091config CONFIG_FEATURE_AIX_LABEL
Rob Landley2ec922e2006-04-13 23:22:16 +000092 bool "Support AIX disklabels"
Eric Andersenc9f20d92002-12-05 08:41:41 +000093 default n
Eric Andersenc7bda1c2004-03-15 08:29:22 +000094 depends on CONFIG_FDISK && CONFIG_FEATURE_FDISK_WRITABLE
Eric Andersenc9f20d92002-12-05 08:41:41 +000095 help
Eric Andersena0ac4522003-02-27 03:14:04 +000096 Enabling this option allows you to create or change AIX disklabels.
97 Most people can safely leave this option disabled.
Eric Andersenc9f20d92002-12-05 08:41:41 +000098
99config CONFIG_FEATURE_SGI_LABEL
Rob Landley2ec922e2006-04-13 23:22:16 +0000100 bool "Support SGI disklabels"
Eric Andersenc9f20d92002-12-05 08:41:41 +0000101 default n
Glenn L McGrath4dcc2dd2003-01-04 11:56:06 +0000102 depends on CONFIG_FDISK && CONFIG_FEATURE_FDISK_WRITABLE
Eric Andersenc9f20d92002-12-05 08:41:41 +0000103 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000104 Enabling this option allows you to create or change SGI disklabels.
105 Most people can safely leave this option disabled.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000106
107config CONFIG_FEATURE_SUN_LABEL
Rob Landley2ec922e2006-04-13 23:22:16 +0000108 bool "Support SUN disklabels"
Eric Andersenc9f20d92002-12-05 08:41:41 +0000109 default n
Eric Andersenc7bda1c2004-03-15 08:29:22 +0000110 depends on CONFIG_FDISK && CONFIG_FEATURE_FDISK_WRITABLE
Eric Andersenc9f20d92002-12-05 08:41:41 +0000111 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000112 Enabling this option allows you to create or change SUN disklabels.
113 Most people can safely leave this option disabled.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000114
115config CONFIG_FEATURE_OSF_LABEL
Rob Landley2ec922e2006-04-13 23:22:16 +0000116 bool "Support BSD disklabels"
Eric Andersenc9f20d92002-12-05 08:41:41 +0000117 default n
Glenn L McGrath4dcc2dd2003-01-04 11:56:06 +0000118 depends on CONFIG_FDISK && CONFIG_FEATURE_FDISK_WRITABLE
Eric Andersenc9f20d92002-12-05 08:41:41 +0000119 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000120 Enabling this option allows you to create or change BSD disklabels
121 and define and edit BSD disk slices.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000122
123config CONFIG_FEATURE_FDISK_ADVANCED
Rob Landley2ec922e2006-04-13 23:22:16 +0000124 bool "Support expert mode"
Eric Andersenc9f20d92002-12-05 08:41:41 +0000125 default n
Glenn L McGrath4dcc2dd2003-01-04 11:56:06 +0000126 depends on CONFIG_FDISK && CONFIG_FEATURE_FDISK_WRITABLE
Eric Andersenc9f20d92002-12-05 08:41:41 +0000127 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000128 Enabling this option allows you to do terribly unsafe things like
129 define arbitrary drive geometry, move the beginning of data in a
130 partition, and similarly evil things. Unless you have a very good
131 reason you would be wise to leave this disabled.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000132
133config CONFIG_FREERAMDISK
134 bool "freeramdisk"
135 default n
136 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000137 Linux allows you to create ramdisks. This utility allows you to
138 delete them and completely free all memory that was used for the
139 ramdisk. For example, if you boot Linux into a ramdisk and later
140 pivot_root, you may want to free the memory that is allocated to the
141 ramdisk. If you have no use for freeing memory from a ramdisk, leave
142 this disabled.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000143
144config CONFIG_FSCK_MINIX
145 bool "fsck_minix"
146 default n
147 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000148 The minix filesystem is a nice, small, compact, read-write filesystem
149 with little overhead. It is not a journaling filesystem however and
Eric Andersen88c916b2003-10-22 09:58:56 +0000150 can experience corruption if it is not properly unmounted or if the
Eric Andersena0ac4522003-02-27 03:14:04 +0000151 power goes off in the middle of a write. This utility allows you to
152 check for and attempt to repair any corruption that occurs to a minix
153 filesystem.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000154
155config CONFIG_MKFS_MINIX
156 bool "mkfs_minix"
157 default n
158 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000159 The minix filesystem is a nice, small, compact, read-write filesystem
160 with little overhead. If you wish to be able to create minix filesystems
161 this utility will do the job for you.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000162
163comment "Minix filesystem support"
164 depends on CONFIG_FSCK_MINIX || CONFIG_MKFS_MINIX
165
166config CONFIG_FEATURE_MINIX2
Rob Landley2ec922e2006-04-13 23:22:16 +0000167 bool "Support Minix fs v2 (fsck_minix/mkfs_minix)"
Eric Andersenc9f20d92002-12-05 08:41:41 +0000168 default y
169 depends on CONFIG_FSCK_MINIX || CONFIG_MKFS_MINIX
170 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000171 If you wish to be able to create version 2 minix filesystems, enable this.
172 If you enabled 'mkfs_minix' then you almost certainly want to be using the
173 version 2 filesystem support.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000174
175config CONFIG_GETOPT
176 bool "getopt"
177 default n
178 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000179 The getopt utility is used to break up (parse) options in command
180 lines to make it easy to write complex shell scripts that also check
181 for legal (and illegal) options. If you want to write horribly
182 complex shell scripts, or use some horribly complex shell script
183 written by others, this utility may be for you. Most people will
184 wisely leave this disabled.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000185
186config CONFIG_HEXDUMP
187 bool "hexdump"
188 default n
189 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000190 The hexdump utility is used to display binary data in a readable
191 way that is comparable to the output from most hex editors.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000192
193config CONFIG_HWCLOCK
194 bool "hwclock"
195 default n
196 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000197 The hwclock utility is used to read and set the hardware clock
Eric Andersen88c916b2003-10-22 09:58:56 +0000198 on a system. This is primarily used to set the current time on
199 shutdown in the hardware clock, so the hardware will keep the
200 correct time when Linux is _not_ running.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000201
Bernhard Reutner-Fischer01d23ad2006-05-26 20:19:22 +0000202config CONFIG_FEATURE_HWCLOCK_LONG_OPTIONS
Rob Landley2ec922e2006-04-13 23:22:16 +0000203 bool "Support long options (--hctosys,...)"
Eric Andersenc9f20d92002-12-05 08:41:41 +0000204 default n
Bernhard Reutner-Fischer01d23ad2006-05-26 20:19:22 +0000205 depends on CONFIG_HWCLOCK && CONFIG_GETOPT_LONG
Eric Andersenc9f20d92002-12-05 08:41:41 +0000206 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000207 By default, the hwclock utility only uses short options. If you
Eric Andersen88c916b2003-10-22 09:58:56 +0000208 are overly fond of its long options, such as --hctosys, --utc, etc)
Eric Andersena0ac4522003-02-27 03:14:04 +0000209 then enable this option.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000210
Mike Frysinger747fc5d2005-09-28 03:21:21 +0000211config CONFIG_FEATURE_HWCLOCK_ADJTIME_FHS
Rob Landley2ec922e2006-04-13 23:22:16 +0000212 bool "Use FHS /var/lib/hwclock/adjtime"
Mike Frysinger747fc5d2005-09-28 03:21:21 +0000213 default y
214 depends on CONFIG_HWCLOCK
215 help
216 Starting with FHS 2.3, the adjtime state file is supposed to exist
Tim Rikerc1ef7bd2006-01-25 00:08:53 +0000217 at /var/lib/hwclock/adjtime instead of /etc/adjtime. If you wish
Mike Frysinger747fc5d2005-09-28 03:21:21 +0000218 to use the FHS behavior, answer Y here, otherwise answer N for the
219 classic /etc/adjtime path.
220
221 http://www.pathname.com/fhs/pub/fhs-2.3.html#VARLIBHWCLOCKSTATEDIRECTORYFORHWCLO
222
Rob Landley6eb1e412005-06-20 04:30:36 +0000223config CONFIG_IPCRM
224 bool "ipcrm"
225 default n
Eric Andersen576db482005-06-23 18:58:57 +0000226 select CONFIG_FEATURE_SUID
Rob Landley6eb1e412005-06-20 04:30:36 +0000227 help
228 The ipcrm utility allows the removal of System V interprocess
229 communication (IPC) objects and the associated data structures
230 from the system.
231
232config CONFIG_IPCS
233 bool "ipcs"
234 default n
Eric Andersen576db482005-06-23 18:58:57 +0000235 select CONFIG_FEATURE_SUID
Rob Landley6eb1e412005-06-20 04:30:36 +0000236 help
237 The ipcs utility is used to provide information on the currently
238 allocated System V interprocess (IPC) objects in the system.
239
Mike Frysinger75aa1922005-09-24 23:12:38 +0000240config CONFIG_LOSETUP
241 bool "losetup"
242 default n
243 help
244 losetup is used to associate or detach a loop device with a regular
245 file or block device, and to query the status of a loop device. This
246 version does not currently support enabling data encryption.
247
Rob Landley70f7ef72005-12-13 08:21:33 +0000248config CONFIG_MDEV
249 bool "mdev"
250 default n
251 help
252 mdev is a mini-udev implementation: call it with -s to populate
Mike Frysinger55092282006-02-02 23:14:57 +0000253 /dev from /sys, then "echo /sbin/mdev > /proc/sys/kernel/hotplug" to
Rob Landley70f7ef72005-12-13 08:21:33 +0000254 have it handle hotplug events afterwards. Device names are taken
255 from sysfs.
256
Rob Landleyb56c2852005-12-17 10:52:30 +0000257config CONFIG_FEATURE_MDEV_CONF
Rob Landley2ec922e2006-04-13 23:22:16 +0000258 bool "Support /etc/mdev.conf"
Rob Landley70f7ef72005-12-13 08:21:33 +0000259 default n
260 depends on CONFIG_MDEV
261 help
262 The mdev config file contains lines that look like:
263
264 hd[a-z][0-9]* 0:3 660
265
266 That's device name (with regex match), uid:gid, and permissions.
267
Rob Landley70f7ef72005-12-13 08:21:33 +0000268 Config file parsing stops on the first matching line. If no config
269 entry is matched, devices are created with default 0:0 660. (Make
270 the last line match .* to override this.)
271
Rob Landleyef10d522006-06-26 14:11:33 +0000272config CONFIG_FEATURE_MDEV_EXEC
273 bool "Support command execution at device addition/removal"
274 default n
275 depends on CONFIG_FEATURE_MDEV_CONF
276 help
277 This adds support for an optional field to /etc/mdev.conf, consisting
278 of a special character and a command line to run after creating the
279 corresponding device(s) and before removing, ala:
280
281 hdc root:cdrom 660 *ln -s $MDEV cdrom
282
283 The $MDEV environment variable is set to the name of the device.
284
285 The special characters and their meanings are:
286 @ Run after creating the device.
287 $ Run before removing the device.
288 * Run both after creating and before removing the device.
289
290 Commands are executed via system() so you need /bin/sh, meaning you
291 probably want to select a default shell in the Shells menu.
292
Eric Andersenc9f20d92002-12-05 08:41:41 +0000293config CONFIG_MKSWAP
294 bool "mkswap"
295 default n
296 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000297 The mkswap utility is used to configure a file or disk partition as
298 Linux swap space. This allows Linux to use the entire file or
299 partition as if it were additional RAM, which can greatly increase
300 the capability of low-memory machines. This additional memory is
301 much slower than real RAM, but can be very helpful at preventing your
Eric Andersen88c916b2003-10-22 09:58:56 +0000302 applications being killed by the Linux out of memory (OOM) killer.
303 Once you have created swap space using 'mkswap' you need to enable
304 the swap space using the 'swapon' utility.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000305
Bernhard Reutner-Fischer56dd0bf2006-03-29 17:32:24 +0000306config CONFIG_FEATURE_MKSWAP_V0
Rob Landley2ec922e2006-04-13 23:22:16 +0000307 bool "version 0 support"
Bernhard Reutner-Fischer56dd0bf2006-03-29 17:32:24 +0000308 default n
309 depends on CONFIG_MKSWAP
310# depends on CONFIG_MKSWAP && CONFIG_DEPRECATED
311 help
312 Enable support for the old v0 style.
313 If your kernel is older than 2.1.117, then v0 support is the
314 only option.
315
Eric Andersenc9f20d92002-12-05 08:41:41 +0000316config CONFIG_MORE
317 bool "more"
318 default n
319 help
Eric Andersen88c916b2003-10-22 09:58:56 +0000320 more is a simple utility which allows you to read text one screen
Eric Andersena0ac4522003-02-27 03:14:04 +0000321 sized page at a time. If you want to read text that is larger than
322 the screen, and you are using anything faster than a 300 baud modem,
323 you will probably find this utility very helpful. If you don't have
324 any need to reading text files, you can leave this disabled.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000325
326config CONFIG_FEATURE_USE_TERMIOS
Rob Landley2ec922e2006-04-13 23:22:16 +0000327 bool "Use termios to manipulate the screen"
Eric Andersenc9f20d92002-12-05 08:41:41 +0000328 default y
329 depends on CONFIG_MORE
330 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000331 This option allows utilities such as 'more' and 'top' to determine
332 the size of the screen. If you leave this disabled, your utilities
Eric Andersen88c916b2003-10-22 09:58:56 +0000333 that display things on the screen will be especially primitive and
Eric Andersena0ac4522003-02-27 03:14:04 +0000334 will be unable to determine the current screen size, and will be
335 unable to move the cursor.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000336
Mike Frysinger55092282006-02-02 23:14:57 +0000337config CONFIG_MOUNT
338 bool "mount"
339 default n
340 help
341 All files and filesystems in Unix are arranged into one big directory
342 tree. The 'mount' utility is used to graft a filesystem onto a
343 particular part of the tree. A filesystem can either live on a block
344 device, or it can be accessible over the network, as is the case with
345 NFS filesystems. Most people using BusyBox will also want to enable
346 the 'mount' utility.
347
348config CONFIG_FEATURE_MOUNT_NFS
Rob Landley2ec922e2006-04-13 23:22:16 +0000349 bool "Support mounting NFS file systems"
Mike Frysinger55092282006-02-02 23:14:57 +0000350 default n
351 depends on CONFIG_MOUNT
352 help
353 Enable mounting of NFS file systems.
354
Eric Andersenc9f20d92002-12-05 08:41:41 +0000355config CONFIG_PIVOT_ROOT
356 bool "pivot_root"
357 default n
358 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000359 The pivot_root utility swaps the mount points for the root filesystem
360 with some other mounted filesystem. This allows you to do all sorts
361 of wild and crazy things with your Linux system and is far more
362 powerful than 'chroot'.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000363
Rob Landley0f34a822005-10-27 22:55:50 +0000364 Note: This is for initrd in linux 2.4. Under initramfs (introduced
365 in linux 2.6) use switch_root instead.
366
Eric Andersenc9f20d92002-12-05 08:41:41 +0000367config CONFIG_RDATE
368 bool "rdate"
369 default n
370 help
Eric Andersenc7bda1c2004-03-15 08:29:22 +0000371 The rdate utility allows you to synchronize the date and time of your
Eric Andersena0ac4522003-02-27 03:14:04 +0000372 system clock with the date and time of a remote networked system using
373 the RFC868 protocol, which is built into the inetd daemon on most
374 systems.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000375
Mike Frysinger75aa1922005-09-24 23:12:38 +0000376config CONFIG_READPROFILE
377 bool "readprofile"
378 default n
379 help
380 This allows you to parse /proc/profile for basic profiling.
381
Mike Frysinger0a6b0bf2006-02-21 04:26:52 +0000382config CONFIG_SETARCH
383 bool "setarch"
384 default n
385 help
386 The linux32 utility is used to create a 32bit environment for the
387 specified program (usually a shell). It only makes sense to have
388 this util on a system that supports both 64bit and 32bit userland
389 (like amd64/x86, ppc64/ppc, sparc64/sparc, etc...).
390
Eric Andersenc9f20d92002-12-05 08:41:41 +0000391config CONFIG_SWAPONOFF
392 bool "swaponoff"
393 default n
394 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000395 This option enables both the 'swapon' and the 'swapoff' utilities.
396 Once you have created some swap space using 'mkswap', you also need
397 to enable your swap space with the 'swapon' utility. The 'swapoff'
398 utility is used, typically at system shutdown, to disable any swap
399 space. If you are not using any swap space, you can leave this
400 option disabled.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000401
Mike Frysinger55092282006-02-02 23:14:57 +0000402config CONFIG_SWITCH_ROOT
403 bool "switch_root"
Eric Andersenc9f20d92002-12-05 08:41:41 +0000404 default n
405 help
Mike Frysinger55092282006-02-02 23:14:57 +0000406 The switch_root utility is used from initramfs to select a new
407 root device. Under initramfs, you have to use this instead of
408 pivot_root. (Stop reading here if you don't care why.)
Eric Andersenc9f20d92002-12-05 08:41:41 +0000409
Mike Frysinger55092282006-02-02 23:14:57 +0000410 Booting with initramfs extracts a gzipped cpio archive into rootfs
411 (which is a variant of ramfs/tmpfs). Because rootfs can't be moved
412 or unmounted*, pivot_root will not work from initramfs. Instead,
413 switch_root deletes everything out of rootfs (including itself),
414 does a mount --move that overmounts rootfs with the new root, and
415 then execs the specified init program.
416
417 * Because the Linux kernel uses rootfs internally as the starting
418 and ending point for searching through the kernel's doubly linked
419 list of active mount points. That's why.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000420
421config CONFIG_UMOUNT
422 bool "umount"
423 default n
424 help
Eric Andersena0ac4522003-02-27 03:14:04 +0000425 When you want to remove a mounted filesystem from its current mount point,
426 for example when you are shutting down the system, the 'umount' utility is
427 the tool to use. If you enabled the 'mount' utility, you almost certainly
428 also want to enable 'umount'.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000429
Rob Landleycc6d8d32006-02-08 20:06:57 +0000430config CONFIG_FEATURE_UMOUNT_ALL
Rob Landley2ec922e2006-04-13 23:22:16 +0000431 bool "umount -a option"
Rob Landleycc6d8d32006-02-08 20:06:57 +0000432 default n
433 depends on CONFIG_UMOUNT
434 help
435 Support -a option to unmount all currently mounted filesystems.
436
Eric Andersenc9f20d92002-12-05 08:41:41 +0000437comment "Common options for mount/umount"
438 depends on CONFIG_MOUNT || CONFIG_UMOUNT
439
440config CONFIG_FEATURE_MOUNT_LOOP
Rob Landley2ec922e2006-04-13 23:22:16 +0000441 bool "Support loopback mounts"
Eric Andersenc9f20d92002-12-05 08:41:41 +0000442 default n
443 depends on CONFIG_MOUNT || CONFIG_UMOUNT
444 help
Rob Landley6a6798b2005-08-10 20:35:54 +0000445 Enabling this feature allows automatic mounting of files (containing
446 filesystem images) via the linux kernel's loopback devices. The mount
447 command will detect you are trying to mount a file instead of a block
448 device, and transparently associate the file with a loopback device.
449 The umount command will also free that loopback device.
Tim Rikerc1ef7bd2006-01-25 00:08:53 +0000450
Rob Landley6a6798b2005-08-10 20:35:54 +0000451 You can still use the 'losetup' utility (to manually associate files
452 with loop devices) if you need to do something advanced, such as
453 specify an offset or cryptographic options to the loopback device.
454 (If you don't want umount to free the loop device, use "umount -D".)
Paul Fox3f6f3172005-07-19 20:55:37 +0000455
Eric Andersenc9f20d92002-12-05 08:41:41 +0000456config CONFIG_FEATURE_MTAB_SUPPORT
Rob Landley2ec922e2006-04-13 23:22:16 +0000457 bool "Support for the old /etc/mtab file"
Eric Andersenc9f20d92002-12-05 08:41:41 +0000458 default n
459 depends on CONFIG_MOUNT || CONFIG_UMOUNT
460 help
Rob Landley6a6798b2005-08-10 20:35:54 +0000461 Historically, Unix systems kept track of the currently mounted
462 partitions in the file "/etc/mtab". These days, the kernel exports
463 the list of currently mounted partitions in "/proc/mounts", rendering
464 the old mtab file obsolete. (In modern systems, /etc/mtab should be
465 a symlink to /proc/mounts.)
Eric Andersena0ac4522003-02-27 03:14:04 +0000466
Rob Landley6a6798b2005-08-10 20:35:54 +0000467 The only reason to have mount maintain an /etc/mtab file itself is if
468 your stripped-down embedded system does not have a /proc directory.
469 If you must use this, keep in mind it's inherently brittle (for
470 example a mount under chroot won't update it), can't handle modern
471 features like separate per-process filesystem namespaces, requires
472 that your /etc directory be writeable, tends to get easily confused
Rob Landley17507fa2006-05-08 02:22:24 +0000473 by --bind or --move mounts, won't update if you rename a directory
474 that contains a mount point, and so on. (In brief: avoid.)
475
476 About the only reason to use this is if you've removed /proc from
477 your kernel.
Eric Andersenc9f20d92002-12-05 08:41:41 +0000478
Eric Andersenc9f20d92002-12-05 08:41:41 +0000479endmenu
480