Lines Matching +full:system +full:- +full:on +full:- +full:module
1 .. SPDX-License-Identifier: GPL-2.0
4 ROMFS - ROM File System
11 file system which doesn't take up useful memory from the router
15 defunct) filesystems, compiled as module need more than 20000 bytes,
19 nfs module with nfsroot is about 57K. Furthermore, as a bit unfair
23 To create such a file system, you'll need a user program named
24 genromfs. It is available on http://romfs.sourceforge.net/
26 As the name suggests, romfs could be also used (space-efficiently) on
27 various read-only media, like (E)EPROM disks if someone will have the
31 which has only this filesystem linked in, and then can load any module
32 later, with the current module utilities. It can also be used to run
34 floppy drives can be loaded later if you use the "initrd"--initial
35 RAM disk--feature of the kernel. This would not be really news
41 module. The kernel can be small enough, since it doesn't have other
42 filesystems, like the quite large ext2fs module, which can then be
49 romfs operates on block devices as you can expect, and the underlying
50 structure is very simple. Every accessible structure begins on 16
53 name). The maximum overhead for any non-empty file is the header, and
62 +---+---+---+---+
63 0 | - | r | o | m | \
64 +---+---+---+---+ The ASCII representation of those bytes
65 4 | 1 | f | s | - | / (i.e. "-rom1fs-")
66 +---+---+---+---+
68 +---+---+---+---+
70 +---+---+---+---+
73 +---+---+---+---+
78 now on) must be in big endian order.
90 The following bytes are now part of the file system; each file header
91 must begin on a 16 byte boundary::
95 +---+---+---+---+
97 +---+---+---+---+ (zero if no more files)
99 +---+---+---+---+
101 +---+---+---+---+
103 +---+---+---+---+ name, and padding
106 +---+---+---+---+
129 5 char device - " -
139 using the executable bits for special purposes on the socket and fifo
145 Another thing to note is that romfs works on file headers and data
147 device drivers are unable to cope with smaller than block-sized data.
148 To overcome this limitation, the whole size of the file system must be
151 If you have any problems or suggestions concerning this file system,
154 this file system is the small code. On the other hand, don't be
163 to romfs-subscribe@shadow.banki.hu, the content is irrelevant.
167 - Permissions and owner information are pretty essential features of a
168 Un*x like system, but romfs does not provide the full possibilities.
171 - The file system is read only, so it can be very small, but in case
172 one would want to write _anything_ to a file system, he still needs
173 a writable file system, thus negating the size advantages. Possible
174 solutions: implement write access as a compile-time option, or a new,
177 - Since the files are only required to have alignment on a 16 byte
184 - Compression might be an useful feature, but memory is quite a
187 - Where it is used?
189 - Does it work on other architectures than intel and motorola?