Lines Matching +full:os +full:- +full:data +full:- +full:offset
1 .. SPDX-License-Identifier: GPL-2.0
12 for NetBSD, FreeBSD, the GNU HURD, Windows 95/98/NT, OS/2 and RISC OS.
18 set using tune2fs(8). Kernel-determined defaults are indicated by (*).
34 errors=remount-ro Remount the filesystem read-only on an error.
40 nouid32 Use 16-bit UIDs and GIDs.
84 ------
93 ------------
97 of consecutive data. Information about each block group is kept in a
105 as the inode table for that block group and the remainder are the data
106 blocks. The block allocation algorithm attempts to allocate data blocks
110 --------------
114 offset of 1024 bytes from the start of the device, and it is essential
129 and which OS created it.
140 ------
145 data held in the object and all of the metadata about an object except
162 There are pointers to the first 12 blocks which contain the file's data
164 pointers to the next set of blocks), a pointer to a doubly-indirect
166 trebly-indirect block (which contains pointers to doubly-indirect blocks).
168 The flags field contains some ext2-specific flags which aren't catered
171 behaviour on a per-file basis. There are flags for secure deletion,
172 undeletable, compression, synchronous updates, immutability, append-only,
173 dumpable, no-atime, indexed directories, and data-journaling. Not all
177 -----------
190 The current implementation of ext2 uses a singly-linked list to store
198 -------------
201 special mention because the data for them is stored within the inode
203 which would normally be used to store the pointers to data blocks.
207 Character and block special devices never have data blocks assigned to
209 the fields which would be used to point to the data blocks.
212 --------------
215 for a particular user (normally the super-user). This is intended to
216 allow for the system to continue functioning even if non-privileged users
222 ----------------
233 ---------------------
240 revision 1. There are three 32-bit fields, one for compatible features
241 (COMPAT), one for read-only compatible (RO_COMPAT) features and one for
247 but the on-disk format is 100% compatible with older on-disk formats, so
254 a regular file with data blocks in it so the kernel does not need to
257 An RO_COMPAT flag indicates that the on-disk format is 100% compatible
258 with older on-disk formats for reading (i.e. the feature does not change
259 the visible on-disk format). However, an old kernel writing to such a
262 sparse groups allow file data blocks where superblock/group descriptor
268 An INCOMPAT flag indicates the on-disk format has changed in some
273 The COMPRESSION flag is an obvious INCOMPAT flag - if the kernel
275 read() instead of it automatically decompressing your data. The ext3
290 --------
300 - per-file if you have the program source: use the O_SYNC flag to open()
301 - per-file if you don't have the source: use "chattr +S" on the file
302 - per-filesystem: add the "sync" option to mount (or in /etc/fstab)
308 -----------
310 There are various limits imposed by the on-disk layout of ext2. Other
314 data blocks is fixed at filesystem creation time, so the only way to
318 Most of these limits could be overcome with slight changes in the on-disk
337 There is a "soft" upper limit of about 10-15k files in a single directory
338 with the current linear linked-list directory implementation. This limit
341 (under development) allows 100k-1M+ files in a single directory without
347 enough 4-character names to make up unique directory entries, so they
352 ----------
357 to the on-disk ext2 layout. In a nutshell, the journal is a regular
358 file which stores whole metadata (and optionally data) blocks that have
361 the need for data conversion.
393 OS/2 [2]_ ftp://metalab.unc.edu/pub/Linux/system/filesystems/ext2/
394 RISC OS client http://www.esw-heim.tu-clausthal.de/~marco/smorbrod/IscaFS/