diff options
Diffstat (limited to 'Documentation/filesystems/ext3.txt')
| -rw-r--r-- | Documentation/filesystems/ext3.txt | 77 |
1 files changed, 47 insertions, 30 deletions
diff --git a/Documentation/filesystems/ext3.txt b/Documentation/filesystems/ext3.txt index b45f3c1b8b4..7ed0d17d672 100644 --- a/Documentation/filesystems/ext3.txt +++ b/Documentation/filesystems/ext3.txt @@ -14,6 +14,11 @@ Options When mounting an ext3 filesystem, the following option are accepted: (*) == default +ro Mount filesystem read only. Note that ext3 will replay + the journal (and thus write to the partition) even when + mounted "read only". Mount options "ro,noload" can be + used to prevent writes to the filesystem. + journal=update Update the ext3 file system's journal to the current format. @@ -21,13 +26,16 @@ journal=inum When a journal already exists, this option is ignored. Otherwise, it specifies the number of the inode which will represent the ext3 file system's journal file. +journal_path=path journal_dev=devnum When the external journal device's major/minor numbers - have changed, this option allows the user to specify + have changed, these options allow the user to specify the new journal location. The journal device is - identified through its new major/minor numbers encoded - in devnum. + identified through either its new major/minor numbers + encoded in devnum, or via a path to the device. -noload Don't load the journal on mounting. +norecovery Don't load the journal on mounting. Note that this forces +noload mount of inconsistent filesystem, which can lead to + various problems. data=journal All data are committed into the journal prior to being written into the main file system. @@ -52,16 +60,19 @@ commit=nrsec (*) Ext3 can be told to sync all its data and metadata Setting it to very large values will improve performance. -barrier=1 This enables/disables barriers. barrier=0 disables - it, barrier=1 enables it. - -orlov (*) This enables the new Orlov block allocator. It is - enabled by default. - -oldalloc This disables the Orlov block allocator and enables - the old block allocator. Orlov should have better - performance - we'd like to get some feedback if it's - the contrary for you. +barrier=<0|1(*)> This enables/disables the use of write barriers in +barrier (*) the jbd code. barrier=0 disables, barrier=1 enables. +nobarrier This also requires an IO stack which can support + barriers, and if jbd gets an error on a barrier + write, it will disable again with a warning. + Write barriers enforce proper on-disk ordering + of journal commits, making volatile disk write caches + safe to use, at some performance penalty. If + your disks are battery-backed in one way or another, + disabling barriers may safely improve performance. + The mount options "barrier" and "nobarrier" can + also be used to enable or disable barriers, for + consistency with other ext3 mount options. user_xattr Enables Extended User Attributes. Additionally, you need to have extended attribute support enabled in the @@ -92,9 +103,17 @@ nocheck debug Extra debugging information is sent to syslog. -errors=remount-ro(*) Remount the filesystem read-only on an error. +errors=remount-ro Remount the filesystem read-only on an error. errors=continue Keep going on a filesystem error. errors=panic Panic and halt the machine if an error occurs. + (These mount options override the errors behavior + specified in the superblock, which can be + configured using tune2fs.) + +data_err=ignore(*) Just print an error message if an error occurs + in a file data buffer in ordered mode. +data_err=abort Abort the journal if an error occurs in a file + data buffer in ordered mode. grpid Give objects the same group ID as their creator. bsdgroups @@ -108,19 +127,18 @@ resuid=n The user ID which may use the reserved blocks. sb=n Use alternate superblock at this location. -quota -noquota -grpquota -usrquota - -bh (*) ext3 associates buffer heads to data pages to -nobh (a) cache disk block mapping information - (b) link pages into transaction to provide - ordering guarantees. - "bh" option forces use of buffer heads. - "nobh" option tries to avoid associating buffer - heads (supported only for "writeback" mode). +quota These options are ignored by the filesystem. They +noquota are used only by quota tools to recognize volumes +grpquota where quota should be turned on. See documentation +usrquota in the quota-tools package for more details + (http://sourceforge.net/projects/linuxquota). +jqfmt=<quota type> These options tell filesystem details about quota +usrjquota=<file> so that quota information can be properly updated +grpjquota=<file> during journal replay. They replace the above + quota options. See documentation in the quota-tools + package for more details + (http://sourceforge.net/projects/linuxquota). Specification ============= @@ -193,6 +211,5 @@ kernel source: <file:fs/ext3/> programs: http://e2fsprogs.sourceforge.net/ http://ext2resize.sourceforge.net -useful links: http://www.zip.com.au/~akpm/linux/ext3/ext3-usage.html - http://www-106.ibm.com/developerworks/linux/library/l-fs7/ - http://www-106.ibm.com/developerworks/linux/library/l-fs8/ +useful links: http://www.ibm.com/developerworks/library/l-fs7/index.html + http://www.ibm.com/developerworks/library/l-fs8/index.html |