mirror of
https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git
synced 2026-10-30 03:27:44 -04:00
Further restructure ext4 documentation; fix up ext4's delayed
allocation for bigalloc file systems; fix up some syzbot-detected races in EXT4_IOC_MOVE_EXT, EXT4_IOC_SWAP_BOOT, and ext4_remount; and a few other miscellaneous bugs and optimizations. -----BEGIN PGP SIGNATURE----- iQEzBAABCAAdFiEEK2m5VNv+CHkogTfJ8vlZVpUNgaMFAlvQYEcACgkQ8vlZVpUN gaOPYAgAh0BF7mTRnHAp/qkR5ZhDi3ecb3TpNlnpfzoDqQhPYETFisc18DD4HwTj wctwzSdYxYodeuPIK+R2bBzUy3FuSwtlER9cdr1ilcrUYPZHbir1rPPfTNb/oDGx WNcd/aulLjuU1eKDODowqMOF2HDchiJHqJqMBa+LfCHck1x/bt2uqdjNA5A1p5AV lp07DoXT54q5rWJDaXpbxTShWKhzHlRKbB9PKEvMHgPNl9sn5oRReRMKAW+WkT91 e3mfy/GhzhugdWxYUg2oAn3dbqYkkAjW96WnBhCQHioW9ASphjl7yBi1LWh2aPA4 haGxe5W3En8q678ZVtTVNJOyvbW81Q== =VgdS -----END PGP SIGNATURE----- Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: - further restructure ext4 documentation - fix up ext4's delayed allocation for bigalloc file systems - fix up some syzbot-detected races in EXT4_IOC_MOVE_EXT, EXT4_IOC_SWAP_BOOT, and ext4_remount - ... and a few other miscellaneous bugs and optimizations. * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (21 commits) ext4: fix use-after-free race in ext4_remount()'s error path ext4: cache NULL when both default_acl and acl are NULL docs: promote the ext4 data structures book to top level docs: move ext4 administrative docs to admin-guide/ jbd2: fix use after free in jbd2_log_do_checkpoint() ext4: propagate error from dquot_initialize() in EXT4_IOC_FSSETXATTR ext4: fix setattr project check in fssetxattr ioctl docs: make ext4 readme tables readable docs: fix ext4 documentation table formatting problems docs: generate a separate ext4 pdf file from the documentation ext4: convert fault handler to use vm_fault_t type ext4: initialize retries variable in ext4_da_write_inline_data_begin() ext4: fix EXT4_IOC_SWAP_BOOT ext4: fix build error when DX_DEBUG is defined ext4: fix argument checking in EXT4_IOC_MOVE_EXT ext4: fix reserved cluster accounting at page invalidation time ext4: adjust reserved cluster count when removing extents ext4: reduce reserved cluster count by number of allocated clusters ext4: fix reserved cluster accounting at delayed write time ext4: add new pending reservation mechanism ...
This commit is contained in:
Linus Torvalds
commit
5993692f09
44 changed files with 1984 additions and 1169 deletions
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@ -30,7 +30,7 @@ Extended attributes, when stored after the inode, have a header
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``ext4_xattr_ibody_header`` that is 4 bytes long:
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.. list-table::
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:widths: 1 1 1 77
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:widths: 8 8 24 40
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:header-rows: 1
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* - Offset
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@ -47,7 +47,7 @@ The beginning of an extended attribute block is in
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``struct ext4_xattr_header``, which is 32 bytes long:
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.. list-table::
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:widths: 1 1 1 77
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:widths: 8 8 24 40
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:header-rows: 1
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* - Offset
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@ -92,7 +92,7 @@ entries must be stored in sorted order. The sort order is
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Attributes stored inside an inode do not need be stored in sorted order.
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.. list-table::
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:widths: 1 1 1 77
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:widths: 8 8 24 40
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:header-rows: 1
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* - Offset
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@ -157,7 +157,7 @@ attribute name index field is set, and matching string is removed from
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the key name. Here is a map of name index values to key prefixes:
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.. list-table::
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:widths: 1 79
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:widths: 16 64
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:header-rows: 1
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* - Name Index
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@ -28,7 +28,7 @@ of checksum. The checksum function is whatever the superblock describes
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(crc32c as of October 2013) unless noted otherwise.
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.. list-table::
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:widths: 1 1 4
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:widths: 20 8 50
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:header-rows: 1
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* - Metadata
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@ -34,7 +34,7 @@ is at most 263 bytes long, though on disk you'll need to reference
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``dirent.rec_len`` to know for sure.
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.. list-table::
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:widths: 1 1 1 77
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:widths: 8 8 24 40
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:header-rows: 1
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* - Offset
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@ -66,7 +66,7 @@ tree traversal. This format is ``ext4_dir_entry_2``, which is at most
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``dirent.rec_len`` to know for sure.
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.. list-table::
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:widths: 1 1 1 77
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:widths: 8 8 24 40
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:header-rows: 1
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* - Offset
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@ -99,7 +99,7 @@ tree traversal. This format is ``ext4_dir_entry_2``, which is at most
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The directory file type is one of the following values:
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.. list-table::
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:widths: 1 79
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:widths: 16 64
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:header-rows: 1
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* - Value
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@ -130,7 +130,7 @@ in the place where the name normally goes. The structure is
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``struct ext4_dir_entry_tail``:
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.. list-table::
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:widths: 1 1 1 77
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:widths: 8 8 24 40
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:header-rows: 1
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* - Offset
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@ -212,7 +212,7 @@ The root of the htree is in ``struct dx_root``, which is the full length
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of a data block:
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.. list-table::
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:widths: 1 1 1 77
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:widths: 8 8 24 40
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:header-rows: 1
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* - Offset
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@ -305,7 +305,7 @@ of a data block:
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The directory hash is one of the following values:
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.. list-table::
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:widths: 1 79
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:widths: 16 64
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:header-rows: 1
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* - Value
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@ -327,7 +327,7 @@ Interior nodes of an htree are recorded as ``struct dx_node``, which is
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also the full length of a data block:
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.. list-table::
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:widths: 1 1 1 77
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:widths: 8 8 24 40
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:header-rows: 1
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* - Offset
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@ -375,7 +375,7 @@ The hash maps that exist in both ``struct dx_root`` and
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long:
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.. list-table::
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:widths: 1 1 1 77
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:widths: 8 8 24 40
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:header-rows: 1
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* - Offset
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@ -405,7 +405,7 @@ directory index (which will ensure that there's space for the checksum.
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The dx\_tail structure is 8 bytes long and looks like this:
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.. list-table::
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:widths: 1 1 1 77
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:widths: 8 8 24 40
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:header-rows: 1
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* - Offset
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|
|
@ -1,613 +0,0 @@
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|||
.. SPDX-License-Identifier: GPL-2.0
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|
||||
========================
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General Information
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||||
========================
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||||
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Ext4 is an advanced level of the ext3 filesystem which incorporates
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scalability and reliability enhancements for supporting large filesystems
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(64 bit) in keeping with increasing disk capacities and state-of-the-art
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feature requirements.
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|
||||
Mailing list: [email protected]
|
||||
Web site: http://ext4.wiki.kernel.org
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|
||||
|
||||
Quick usage instructions
|
||||
========================
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||||
|
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Note: More extensive information for getting started with ext4 can be
|
||||
found at the ext4 wiki site at the URL:
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||||
http://ext4.wiki.kernel.org/index.php/Ext4_Howto
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|
||||
- The latest version of e2fsprogs can be found at:
|
||||
|
||||
https://www.kernel.org/pub/linux/kernel/people/tytso/e2fsprogs/
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||||
|
||||
or
|
||||
|
||||
http://sourceforge.net/project/showfiles.php?group_id=2406
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||||
|
||||
or grab the latest git repository from:
|
||||
|
||||
https://git.kernel.org/pub/scm/fs/ext2/e2fsprogs.git
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||||
|
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- Create a new filesystem using the ext4 filesystem type:
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|
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# mke2fs -t ext4 /dev/hda1
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|
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Or to configure an existing ext3 filesystem to support extents:
|
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|
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# tune2fs -O extents /dev/hda1
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||||
|
||||
If the filesystem was created with 128 byte inodes, it can be
|
||||
converted to use 256 byte for greater efficiency via:
|
||||
|
||||
# tune2fs -I 256 /dev/hda1
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||||
|
||||
- Mounting:
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||||
|
||||
# mount -t ext4 /dev/hda1 /wherever
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||||
|
||||
- When comparing performance with other filesystems, it's always
|
||||
important to try multiple workloads; very often a subtle change in a
|
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workload parameter can completely change the ranking of which
|
||||
filesystems do well compared to others. When comparing versus ext3,
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||||
note that ext4 enables write barriers by default, while ext3 does
|
||||
not enable write barriers by default. So it is useful to use
|
||||
explicitly specify whether barriers are enabled or not when via the
|
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'-o barriers=[0|1]' mount option for both ext3 and ext4 filesystems
|
||||
for a fair comparison. When tuning ext3 for best benchmark numbers,
|
||||
it is often worthwhile to try changing the data journaling mode; '-o
|
||||
data=writeback' can be faster for some workloads. (Note however that
|
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running mounted with data=writeback can potentially leave stale data
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||||
exposed in recently written files in case of an unclean shutdown,
|
||||
which could be a security exposure in some situations.) Configuring
|
||||
the filesystem with a large journal can also be helpful for
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||||
metadata-intensive workloads.
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||||
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||||
Features
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||||
========
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||||
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||||
Currently Available
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||||
-------------------
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||||
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* ability to use filesystems > 16TB (e2fsprogs support not available yet)
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* extent format reduces metadata overhead (RAM, IO for access, transactions)
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* extent format more robust in face of on-disk corruption due to magics,
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* internal redundancy in tree
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* improved file allocation (multi-block alloc)
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* lift 32000 subdirectory limit imposed by i_links_count[1]
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* nsec timestamps for mtime, atime, ctime, create time
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* inode version field on disk (NFSv4, Lustre)
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||||
* reduced e2fsck time via uninit_bg feature
|
||||
* journal checksumming for robustness, performance
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||||
* persistent file preallocation (e.g for streaming media, databases)
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||||
* ability to pack bitmaps and inode tables into larger virtual groups via the
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||||
flex_bg feature
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||||
* large file support
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||||
* inode allocation using large virtual block groups via flex_bg
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||||
* delayed allocation
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* large block (up to pagesize) support
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||||
* efficient new ordered mode in JBD2 and ext4 (avoid using buffer head to force
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||||
the ordering)
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||||
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||||
[1] Filesystems with a block size of 1k may see a limit imposed by the
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directory hash tree having a maximum depth of two.
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||||
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||||
Options
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||||
=======
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||||
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||||
When mounting an ext4 filesystem, the following option are accepted:
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(*) == default
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||||
|
||||
======================= =======================================================
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||||
Mount Option Description
|
||||
======================= =======================================================
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||||
ro Mount filesystem read only. Note that ext4 will
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replay the journal (and thus write to the
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partition) even when mounted "read only". The
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||||
mount options "ro,noload" can be used to prevent
|
||||
writes to the filesystem.
|
||||
|
||||
journal_checksum Enable checksumming of the journal transactions.
|
||||
This will allow the recovery code in e2fsck and the
|
||||
kernel to detect corruption in the kernel. It is a
|
||||
compatible change and will be ignored by older kernels.
|
||||
|
||||
journal_async_commit Commit block can be written to disk without waiting
|
||||
for descriptor blocks. If enabled older kernels cannot
|
||||
mount the device. This will enable 'journal_checksum'
|
||||
internally.
|
||||
|
||||
journal_path=path
|
||||
journal_dev=devnum When the external journal device's major/minor numbers
|
||||
have changed, these options allow the user to specify
|
||||
the new journal location. The journal device is
|
||||
identified through either its new major/minor numbers
|
||||
encoded in devnum, or via a path to the device.
|
||||
|
||||
norecovery Don't load the journal on mounting. Note that
|
||||
noload if the filesystem was not unmounted cleanly,
|
||||
skipping the journal replay will lead to the
|
||||
filesystem containing inconsistencies that can
|
||||
lead to any number of problems.
|
||||
|
||||
data=journal All data are committed into the journal prior to being
|
||||
written into the main file system. Enabling
|
||||
this mode will disable delayed allocation and
|
||||
O_DIRECT support.
|
||||
|
||||
data=ordered (*) All data are forced directly out to the main file
|
||||
system prior to its metadata being committed to the
|
||||
journal.
|
||||
|
||||
data=writeback Data ordering is not preserved, data may be written
|
||||
into the main file system after its metadata has been
|
||||
committed to the journal.
|
||||
|
||||
commit=nrsec (*) Ext4 can be told to sync all its data and metadata
|
||||
every 'nrsec' seconds. The default value is 5 seconds.
|
||||
This means that if you lose your power, you will lose
|
||||
as much as the latest 5 seconds of work (your
|
||||
filesystem will not be damaged though, thanks to the
|
||||
journaling). This default value (or any low value)
|
||||
will hurt performance, but it's good for data-safety.
|
||||
Setting it to 0 will have the same effect as leaving
|
||||
it at the default (5 seconds).
|
||||
Setting it to very large values will improve
|
||||
performance.
|
||||
|
||||
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 ext4 mount options.
|
||||
|
||||
inode_readahead_blks=n This tuning parameter controls the maximum
|
||||
number of inode table blocks that ext4's inode
|
||||
table readahead algorithm will pre-read into
|
||||
the buffer cache. The default value is 32 blocks.
|
||||
|
||||
nouser_xattr Disables Extended User Attributes. See the
|
||||
attr(5) manual page for more information about
|
||||
extended attributes.
|
||||
|
||||
noacl This option disables POSIX Access Control List
|
||||
support. If ACL support is enabled in the kernel
|
||||
configuration (CONFIG_EXT4_FS_POSIX_ACL), ACL is
|
||||
enabled by default on mount. See the acl(5) manual
|
||||
page for more information about acl.
|
||||
|
||||
bsddf (*) Make 'df' act like BSD.
|
||||
minixdf Make 'df' act like Minix.
|
||||
|
||||
debug Extra debugging information is sent to syslog.
|
||||
|
||||
abort Simulate the effects of calling ext4_abort() for
|
||||
debugging purposes. This is normally used while
|
||||
remounting a filesystem which is already mounted.
|
||||
|
||||
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 New objects have the group ID of their parent.
|
||||
bsdgroups
|
||||
|
||||
nogrpid (*) New objects have the group ID of their creator.
|
||||
sysvgroups
|
||||
|
||||
resgid=n The group ID which may use the reserved blocks.
|
||||
|
||||
resuid=n The user ID which may use the reserved blocks.
|
||||
|
||||
sb=n Use alternate superblock at this location.
|
||||
|
||||
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).
|
||||
|
||||
stripe=n Number of filesystem blocks that mballoc will try
|
||||
to use for allocation size and alignment. For RAID5/6
|
||||
systems this should be the number of data
|
||||
disks * RAID chunk size in file system blocks.
|
||||
|
||||
delalloc (*) Defer block allocation until just before ext4
|
||||
writes out the block(s) in question. This
|
||||
allows ext4 to better allocation decisions
|
||||
more efficiently.
|
||||
nodelalloc Disable delayed allocation. Blocks are allocated
|
||||
when the data is copied from userspace to the
|
||||
page cache, either via the write(2) system call
|
||||
or when an mmap'ed page which was previously
|
||||
unallocated is written for the first time.
|
||||
|
||||
max_batch_time=usec Maximum amount of time ext4 should wait for
|
||||
additional filesystem operations to be batch
|
||||
together with a synchronous write operation.
|
||||
Since a synchronous write operation is going to
|
||||
force a commit and then a wait for the I/O
|
||||
complete, it doesn't cost much, and can be a
|
||||
huge throughput win, we wait for a small amount
|
||||
of time to see if any other transactions can
|
||||
piggyback on the synchronous write. The
|
||||
algorithm used is designed to automatically tune
|
||||
for the speed of the disk, by measuring the
|
||||
amount of time (on average) that it takes to
|
||||
finish committing a transaction. Call this time
|
||||
the "commit time". If the time that the
|
||||
transaction has been running is less than the
|
||||
commit time, ext4 will try sleeping for the
|
||||
commit time to see if other operations will join
|
||||
the transaction. The commit time is capped by
|
||||
the max_batch_time, which defaults to 15000us
|
||||
(15ms). This optimization can be turned off
|
||||
entirely by setting max_batch_time to 0.
|
||||
|
||||
min_batch_time=usec This parameter sets the commit time (as
|
||||
described above) to be at least min_batch_time.
|
||||
It defaults to zero microseconds. Increasing
|
||||
this parameter may improve the throughput of
|
||||
multi-threaded, synchronous workloads on very
|
||||
fast disks, at the cost of increasing latency.
|
||||
|
||||
journal_ioprio=prio The I/O priority (from 0 to 7, where 0 is the
|
||||
highest priority) which should be used for I/O
|
||||
operations submitted by kjournald2 during a
|
||||
commit operation. This defaults to 3, which is
|
||||
a slightly higher priority than the default I/O
|
||||
priority.
|
||||
|
||||
auto_da_alloc(*) Many broken applications don't use fsync() when
|
||||
noauto_da_alloc replacing existing files via patterns such as
|
||||
fd = open("foo.new")/write(fd,..)/close(fd)/
|
||||
rename("foo.new", "foo"), or worse yet,
|
||||
fd = open("foo", O_TRUNC)/write(fd,..)/close(fd).
|
||||
If auto_da_alloc is enabled, ext4 will detect
|
||||
the replace-via-rename and replace-via-truncate
|
||||
patterns and force that any delayed allocation
|
||||
blocks are allocated such that at the next
|
||||
journal commit, in the default data=ordered
|
||||
mode, the data blocks of the new file are forced
|
||||
to disk before the rename() operation is
|
||||
committed. This provides roughly the same level
|
||||
of guarantees as ext3, and avoids the
|
||||
"zero-length" problem that can happen when a
|
||||
system crashes before the delayed allocation
|
||||
blocks are forced to disk.
|
||||
|
||||
noinit_itable Do not initialize any uninitialized inode table
|
||||
blocks in the background. This feature may be
|
||||
used by installation CD's so that the install
|
||||
process can complete as quickly as possible; the
|
||||
inode table initialization process would then be
|
||||
deferred until the next time the file system
|
||||
is unmounted.
|
||||
|
||||
init_itable=n The lazy itable init code will wait n times the
|
||||
number of milliseconds it took to zero out the
|
||||
previous block group's inode table. This
|
||||
minimizes the impact on the system performance
|
||||
while file system's inode table is being initialized.
|
||||
|
||||
discard Controls whether ext4 should issue discard/TRIM
|
||||
nodiscard(*) commands to the underlying block device when
|
||||
blocks are freed. This is useful for SSD devices
|
||||
and sparse/thinly-provisioned LUNs, but it is off
|
||||
by default until sufficient testing has been done.
|
||||
|
||||
nouid32 Disables 32-bit UIDs and GIDs. This is for
|
||||
interoperability with older kernels which only
|
||||
store and expect 16-bit values.
|
||||
|
||||
block_validity(*) These options enable or disable the in-kernel
|
||||
noblock_validity facility for tracking filesystem metadata blocks
|
||||
within internal data structures. This allows multi-
|
||||
block allocator and other routines to notice
|
||||
bugs or corrupted allocation bitmaps which cause
|
||||
blocks to be allocated which overlap with
|
||||
filesystem metadata blocks.
|
||||
|
||||
dioread_lock Controls whether or not ext4 should use the DIO read
|
||||
dioread_nolock locking. If the dioread_nolock option is specified
|
||||
ext4 will allocate uninitialized extent before buffer
|
||||
write and convert the extent to initialized after IO
|
||||
completes. This approach allows ext4 code to avoid
|
||||
using inode mutex, which improves scalability on high
|
||||
speed storages. However this does not work with
|
||||
data journaling and dioread_nolock option will be
|
||||
ignored with kernel warning. Note that dioread_nolock
|
||||
code path is only used for extent-based files.
|
||||
Because of the restrictions this options comprises
|
||||
it is off by default (e.g. dioread_lock).
|
||||
|
||||
max_dir_size_kb=n This limits the size of directories so that any
|
||||
attempt to expand them beyond the specified
|
||||
limit in kilobytes will cause an ENOSPC error.
|
||||
This is useful in memory constrained
|
||||
environments, where a very large directory can
|
||||
cause severe performance problems or even
|
||||
provoke the Out Of Memory killer. (For example,
|
||||
if there is only 512mb memory available, a 176mb
|
||||
directory may seriously cramp the system's style.)
|
||||
|
||||
i_version Enable 64-bit inode version support. This option is
|
||||
off by default.
|
||||
|
||||
dax Use direct access (no page cache). See
|
||||
Documentation/filesystems/dax.txt. Note that
|
||||
this option is incompatible with data=journal.
|
||||
======================= =======================================================
|
||||
|
||||
Data Mode
|
||||
=========
|
||||
There are 3 different data modes:
|
||||
|
||||
* writeback mode
|
||||
|
||||
In data=writeback mode, ext4 does not journal data at all. This mode provides
|
||||
a similar level of journaling as that of XFS, JFS, and ReiserFS in its default
|
||||
mode - metadata journaling. A crash+recovery can cause incorrect data to
|
||||
appear in files which were written shortly before the crash. This mode will
|
||||
typically provide the best ext4 performance.
|
||||
|
||||
* ordered mode
|
||||
|
||||
In data=ordered mode, ext4 only officially journals metadata, but it logically
|
||||
groups metadata information related to data changes with the data blocks into
|
||||
a single unit called a transaction. When it's time to write the new metadata
|
||||
out to disk, the associated data blocks are written first. In general, this
|
||||
mode performs slightly slower than writeback but significantly faster than
|
||||
journal mode.
|
||||
|
||||
* journal mode
|
||||
|
||||
data=journal mode provides full data and metadata journaling. All new data is
|
||||
written to the journal first, and then to its final location. In the event of
|
||||
a crash, the journal can be replayed, bringing both data and metadata into a
|
||||
consistent state. This mode is the slowest except when data needs to be read
|
||||
from and written to disk at the same time where it outperforms all others
|
||||
modes. Enabling this mode will disable delayed allocation and O_DIRECT
|
||||
support.
|
||||
|
||||
/proc entries
|
||||
=============
|
||||
|
||||
Information about mounted ext4 file systems can be found in
|
||||
/proc/fs/ext4. Each mounted filesystem will have a directory in
|
||||
/proc/fs/ext4 based on its device name (i.e., /proc/fs/ext4/hdc or
|
||||
/proc/fs/ext4/dm-0). The files in each per-device directory are shown
|
||||
in table below.
|
||||
|
||||
Files in /proc/fs/ext4/<devname>
|
||||
|
||||
================ =======
|
||||
File Content
|
||||
================ =======
|
||||
mb_groups details of multiblock allocator buddy cache of free blocks
|
||||
================ =======
|
||||
|
||||
/sys entries
|
||||
============
|
||||
|
||||
Information about mounted ext4 file systems can be found in
|
||||
/sys/fs/ext4. Each mounted filesystem will have a directory in
|
||||
/sys/fs/ext4 based on its device name (i.e., /sys/fs/ext4/hdc or
|
||||
/sys/fs/ext4/dm-0). The files in each per-device directory are shown
|
||||
in table below.
|
||||
|
||||
Files in /sys/fs/ext4/<devname>:
|
||||
|
||||
(see also Documentation/ABI/testing/sysfs-fs-ext4)
|
||||
|
||||
============================= =================================================
|
||||
File Content
|
||||
============================= =================================================
|
||||
delayed_allocation_blocks This file is read-only and shows the number of
|
||||
blocks that are dirty in the page cache, but
|
||||
which do not have their location in the
|
||||
filesystem allocated yet.
|
||||
|
||||
inode_goal Tuning parameter which (if non-zero) controls
|
||||
the goal inode used by the inode allocator in
|
||||
preference to all other allocation heuristics.
|
||||
This is intended for debugging use only, and
|
||||
should be 0 on production systems.
|
||||
|
||||
inode_readahead_blks Tuning parameter which controls the maximum
|
||||
number of inode table blocks that ext4's inode
|
||||
table readahead algorithm will pre-read into
|
||||
the buffer cache
|
||||
|
||||
lifetime_write_kbytes This file is read-only and shows the number of
|
||||
kilobytes of data that have been written to this
|
||||
filesystem since it was created.
|
||||
|
||||
max_writeback_mb_bump The maximum number of megabytes the writeback
|
||||
code will try to write out before move on to
|
||||
another inode.
|
||||
|
||||
mb_group_prealloc The multiblock allocator will round up allocation
|
||||
requests to a multiple of this tuning parameter if
|
||||
the stripe size is not set in the ext4 superblock
|
||||
|
||||
mb_max_to_scan The maximum number of extents the multiblock
|
||||
allocator will search to find the best extent
|
||||
|
||||
mb_min_to_scan The minimum number of extents the multiblock
|
||||
allocator will search to find the best extent
|
||||
|
||||
mb_order2_req Tuning parameter which controls the minimum size
|
||||
for requests (as a power of 2) where the buddy
|
||||
cache is used
|
||||
|
||||
mb_stats Controls whether the multiblock allocator should
|
||||
collect statistics, which are shown during the
|
||||
unmount. 1 means to collect statistics, 0 means
|
||||
not to collect statistics
|
||||
|
||||
mb_stream_req Files which have fewer blocks than this tunable
|
||||
parameter will have their blocks allocated out
|
||||
of a block group specific preallocation pool, so
|
||||
that small files are packed closely together.
|
||||
Each large file will have its blocks allocated
|
||||
out of its own unique preallocation pool.
|
||||
|
||||
session_write_kbytes This file is read-only and shows the number of
|
||||
kilobytes of data that have been written to this
|
||||
filesystem since it was mounted.
|
||||
|
||||
reserved_clusters This is RW file and contains number of reserved
|
||||
clusters in the file system which will be used
|
||||
in the specific situations to avoid costly
|
||||
zeroout, unexpected ENOSPC, or possible data
|
||||
loss. The default is 2% or 4096 clusters,
|
||||
whichever is smaller and this can be changed
|
||||
however it can never exceed number of clusters
|
||||
in the file system. If there is not enough space
|
||||
for the reserved space when mounting the file
|
||||
mount will _not_ fail.
|
||||
============================= =================================================
|
||||
|
||||
Ioctls
|
||||
======
|
||||
|
||||
There is some Ext4 specific functionality which can be accessed by applications
|
||||
through the system call interfaces. The list of all Ext4 specific ioctls are
|
||||
shown in the table below.
|
||||
|
||||
Table of Ext4 specific ioctls
|
||||
|
||||
============================= =================================================
|
||||
Ioctl Description
|
||||
============================= =================================================
|
||||
EXT4_IOC_GETFLAGS Get additional attributes associated with inode.
|
||||
The ioctl argument is an integer bitfield, with
|
||||
bit values described in ext4.h. This ioctl is an
|
||||
alias for FS_IOC_GETFLAGS.
|
||||
|
||||
EXT4_IOC_SETFLAGS Set additional attributes associated with inode.
|
||||
The ioctl argument is an integer bitfield, with
|
||||
bit values described in ext4.h. This ioctl is an
|
||||
alias for FS_IOC_SETFLAGS.
|
||||
|
||||
EXT4_IOC_GETVERSION
|
||||
EXT4_IOC_GETVERSION_OLD
|
||||
Get the inode i_generation number stored for
|
||||
each inode. The i_generation number is normally
|
||||
changed only when new inode is created and it is
|
||||
particularly useful for network filesystems. The
|
||||
'_OLD' version of this ioctl is an alias for
|
||||
FS_IOC_GETVERSION.
|
||||
|
||||
EXT4_IOC_SETVERSION
|
||||
EXT4_IOC_SETVERSION_OLD
|
||||
Set the inode i_generation number stored for
|
||||
each inode. The '_OLD' version of this ioctl
|
||||
is an alias for FS_IOC_SETVERSION.
|
||||
|
||||
EXT4_IOC_GROUP_EXTEND This ioctl has the same purpose as the resize
|
||||
mount option. It allows to resize filesystem
|
||||
to the end of the last existing block group,
|
||||
further resize has to be done with resize2fs,
|
||||
either online, or offline. The argument points
|
||||
to the unsigned logn number representing the
|
||||
filesystem new block count.
|
||||
|
||||
EXT4_IOC_MOVE_EXT Move the block extents from orig_fd (the one
|
||||
this ioctl is pointing to) to the donor_fd (the
|
||||
one specified in move_extent structure passed
|
||||
as an argument to this ioctl). Then, exchange
|
||||
inode metadata between orig_fd and donor_fd.
|
||||
This is especially useful for online
|
||||
defragmentation, because the allocator has the
|
||||
opportunity to allocate moved blocks better,
|
||||
ideally into one contiguous extent.
|
||||
|
||||
EXT4_IOC_GROUP_ADD Add a new group descriptor to an existing or
|
||||
new group descriptor block. The new group
|
||||
descriptor is described by ext4_new_group_input
|
||||
structure, which is passed as an argument to
|
||||
this ioctl. This is especially useful in
|
||||
conjunction with EXT4_IOC_GROUP_EXTEND,
|
||||
which allows online resize of the filesystem
|
||||
to the end of the last existing block group.
|
||||
Those two ioctls combined is used in userspace
|
||||
online resize tool (e.g. resize2fs).
|
||||
|
||||
EXT4_IOC_MIGRATE This ioctl operates on the filesystem itself.
|
||||
It converts (migrates) ext3 indirect block mapped
|
||||
inode to ext4 extent mapped inode by walking
|
||||
through indirect block mapping of the original
|
||||
inode and converting contiguous block ranges
|
||||
into ext4 extents of the temporary inode. Then,
|
||||
inodes are swapped. This ioctl might help, when
|
||||
migrating from ext3 to ext4 filesystem, however
|
||||
suggestion is to create fresh ext4 filesystem
|
||||
and copy data from the backup. Note, that
|
||||
filesystem has to support extents for this ioctl
|
||||
to work.
|
||||
|
||||
EXT4_IOC_ALLOC_DA_BLKS Force all of the delay allocated blocks to be
|
||||
allocated to preserve application-expected ext3
|
||||
behaviour. Note that this will also start
|
||||
triggering a write of the data blocks, but this
|
||||
behaviour may change in the future as it is
|
||||
not necessary and has been done this way only
|
||||
for sake of simplicity.
|
||||
|
||||
EXT4_IOC_RESIZE_FS Resize the filesystem to a new size. The number
|
||||
of blocks of resized filesystem is passed in via
|
||||
64 bit integer argument. The kernel allocates
|
||||
bitmaps and inode table, the userspace tool thus
|
||||
just passes the new number of blocks.
|
||||
|
||||
EXT4_IOC_SWAP_BOOT Swap i_blocks and associated attributes
|
||||
(like i_blocks, i_size, i_flags, ...) from
|
||||
the specified inode with inode
|
||||
EXT4_BOOT_LOADER_INO (#5). This is typically
|
||||
used to store a boot loader in a secure part of
|
||||
the filesystem, where it can't be changed by a
|
||||
normal user by accident.
|
||||
The data blocks of the previous boot loader
|
||||
will be associated with the given inode.
|
||||
============================= =================================================
|
||||
|
||||
References
|
||||
==========
|
||||
|
||||
kernel source: <file:fs/ext4/>
|
||||
<file:fs/jbd2/>
|
||||
|
||||
programs: http://e2fsprogs.sourceforge.net/
|
||||
|
||||
useful links: http://fedoraproject.org/wiki/ext3-devel
|
||||
http://www.bullopensource.org/ext4/
|
||||
http://ext4.wiki.kernel.org/index.php/Main_Page
|
||||
http://fedoraproject.org/wiki/Features/Ext4
|
||||
|
|
@ -43,7 +43,7 @@ entire bitmap.
|
|||
The block group descriptor is laid out in ``struct ext4_group_desc``.
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -157,7 +157,7 @@ The block group descriptor is laid out in ``struct ext4_group_desc``.
|
|||
Block group flags can be any combination of the following:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 16 64
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -68,7 +68,7 @@ The extent tree header is recorded in ``struct ext4_extent_header``,
|
|||
which is 12 bytes long:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -104,7 +104,7 @@ Internal nodes of the extent tree, also known as index nodes, are
|
|||
recorded as ``struct ext4_extent_idx``, and are 12 bytes long:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -134,7 +134,7 @@ Leaf nodes of the extent tree are recorded as ``struct ext4_extent``,
|
|||
and are also 12 bytes long:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -174,7 +174,7 @@ including) the checksum itself.
|
|||
``struct ext4_extent_tail`` is 4 bytes long:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -1,17 +1,14 @@
|
|||
.. SPDX-License-Identifier: GPL-2.0
|
||||
|
||||
===============
|
||||
ext4 Filesystem
|
||||
===============
|
||||
|
||||
General usage and on-disk artifacts writen by ext4. More documentation may
|
||||
be ported from the wiki as time permits. This should be considered the
|
||||
canonical source of information as the details here have been reviewed by
|
||||
the ext4 community.
|
||||
===================================
|
||||
ext4 Data Structures and Algorithms
|
||||
===================================
|
||||
|
||||
.. toctree::
|
||||
:maxdepth: 5
|
||||
:maxdepth: 6
|
||||
:numbered:
|
||||
|
||||
ext4
|
||||
ondisk/index
|
||||
about.rst
|
||||
overview.rst
|
||||
globals.rst
|
||||
dynamic.rst
|
||||
|
|
|
|||
|
|
@ -29,8 +29,9 @@ and the inode structure itself.
|
|||
The inode table entry is laid out in ``struct ext4_inode``.
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
:class: longtable
|
||||
|
||||
* - Offset
|
||||
- Size
|
||||
|
|
@ -176,7 +177,7 @@ The inode table entry is laid out in ``struct ext4_inode``.
|
|||
The ``i_mode`` value is a combination of the following flags:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 16 64
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -227,7 +228,7 @@ The ``i_mode`` value is a combination of the following flags:
|
|||
The ``i_flags`` field is a combination of these values:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 16 64
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -314,7 +315,7 @@ The ``osd1`` field has multiple meanings depending on the creator:
|
|||
Linux:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -331,7 +332,7 @@ Linux:
|
|||
Hurd:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -346,7 +347,7 @@ Hurd:
|
|||
Masix:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -365,7 +366,7 @@ The ``osd2`` field has multiple meanings depending on the filesystem creator:
|
|||
Linux:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -402,7 +403,7 @@ Linux:
|
|||
Hurd:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -433,7 +434,7 @@ Hurd:
|
|||
Masix:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -48,7 +48,7 @@ Layout
|
|||
Generally speaking, the journal has this format:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 78
|
||||
:widths: 16 48 16
|
||||
:header-rows: 1
|
||||
|
||||
* - Superblock
|
||||
|
|
@ -76,7 +76,7 @@ The journal superblock will be in the next full block after the
|
|||
superblock.
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 1 76
|
||||
:widths: 12 12 12 32 12
|
||||
:header-rows: 1
|
||||
|
||||
* - 1024 bytes of padding
|
||||
|
|
@ -98,7 +98,7 @@ Every block in the journal starts with a common 12-byte header
|
|||
``struct journal_header_s``:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -124,7 +124,7 @@ Every block in the journal starts with a common 12-byte header
|
|||
The journal block type can be any one of:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 16 64
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -154,7 +154,7 @@ The journal superblock is recorded as ``struct journal_superblock_s``,
|
|||
which is 1024 bytes long:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -264,7 +264,7 @@ which is 1024 bytes long:
|
|||
The journal compat features are any combination of the following:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 16 64
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -278,7 +278,7 @@ The journal compat features are any combination of the following:
|
|||
The journal incompat features are any combination of the following:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 16 64
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -306,7 +306,7 @@ Journal checksum type codes are one of the following. crc32 or crc32c are the
|
|||
most likely choices.
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 16 64
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -330,7 +330,7 @@ described by a data structure, but here is the block structure anyway.
|
|||
Descriptor blocks consume at least 36 bytes, but use a full block:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -355,7 +355,7 @@ defined as ``struct journal_block_tag3_s``, which looks like the
|
|||
following. The size is 16 or 32 bytes.
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -400,7 +400,7 @@ following. The size is 16 or 32 bytes.
|
|||
The journal tag flags are any combination of the following:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 16 64
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -421,7 +421,7 @@ is defined as ``struct journal_block_tag_s``, which looks like the
|
|||
following. The size is 8, 12, 24, or 28 bytes:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -471,7 +471,7 @@ JBD2\_FEATURE\_INCOMPAT\_CSUM\_V3 are set, the end of the block is a
|
|||
``struct jbd2_journal_block_tail``, which looks like this:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -513,7 +513,7 @@ Revocation blocks are described in
|
|||
length, but use a full block:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -543,7 +543,7 @@ JBD2\_FEATURE\_INCOMPAT\_CSUM\_V3 are set, the end of the revocation
|
|||
block is a ``struct jbd2_journal_revoke_tail``, which has this format:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -567,7 +567,7 @@ The commit block is described by ``struct commit_header``, which is 32
|
|||
bytes long (but uses a full block):
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -32,7 +32,7 @@ The checksum is calculated against the FS UUID and the MMP structure.
|
|||
The MMP structure (``struct mmp_struct``) is as follows:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 12 20 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -1,9 +0,0 @@
|
|||
.. SPDX-License-Identifier: GPL-2.0
|
||||
|
||||
==============================
|
||||
Data Structures and Algorithms
|
||||
==============================
|
||||
.. include:: about.rst
|
||||
.. include:: overview.rst
|
||||
.. include:: globals.rst
|
||||
.. include:: dynamic.rst
|
||||
|
|
@ -6,7 +6,7 @@ Special inodes
|
|||
ext4 reserves some inode for special features, as follows:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 6 70
|
||||
:header-rows: 1
|
||||
|
||||
* - inode Number
|
||||
|
|
@ -19,7 +19,7 @@ The ext4 superblock is laid out as follows in
|
|||
``struct ext4_super_block``:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 1 1 77
|
||||
:widths: 8 8 24 40
|
||||
:header-rows: 1
|
||||
|
||||
* - Offset
|
||||
|
|
@ -483,7 +483,7 @@ The ext4 superblock is laid out as follows in
|
|||
The superblock state is some combination of the following:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 8 72
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -500,7 +500,7 @@ The superblock state is some combination of the following:
|
|||
The superblock error policy is one of the following:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 8 72
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -517,7 +517,7 @@ The superblock error policy is one of the following:
|
|||
The filesystem creator is one of the following:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 8 72
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -538,7 +538,7 @@ The filesystem creator is one of the following:
|
|||
The superblock revision is one of the following:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 8 72
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -556,7 +556,7 @@ The superblock compatible features field is a combination of any of the
|
|||
following:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 16 64
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -595,7 +595,7 @@ The superblock incompatible features field is a combination of any of the
|
|||
following:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 16 64
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -647,7 +647,7 @@ The superblock read-only compatible features field is a combination of any of
|
|||
the following:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 16 64
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -702,7 +702,7 @@ the following:
|
|||
The ``s_def_hash_version`` field is one of the following:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 8 72
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -725,7 +725,7 @@ The ``s_def_hash_version`` field is one of the following:
|
|||
The ``s_default_mount_opts`` field is any combination of the following:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 8 72
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -767,7 +767,7 @@ The ``s_default_mount_opts`` field is any combination of the following:
|
|||
The ``s_flags`` field is any combination of the following:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 8 72
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
|
|
@ -784,7 +784,7 @@ The ``s_flags`` field is any combination of the following:
|
|||
The ``s_encrypt_algos`` list can contain any of the following:
|
||||
|
||||
.. list-table::
|
||||
:widths: 1 79
|
||||
:widths: 8 72
|
||||
:header-rows: 1
|
||||
|
||||
* - Value
|
||||
Loading…
Reference in a new issue