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authorWang Jianjian <wangjianjian3@huawei.com>2022-05-20 10:22:55 +0800
committerTheodore Ts'o <tytso@mit.edu>2022-06-16 11:03:17 -0400
commit3103084afcf2341e12b0ee2c7b2ed570164f44a2 (patch)
treee5e78403de9a5ef0dfee46c8bb7522e1dda5a425 /Documentation/filesystems/ext4
parent48e02e6113825db81e4aacc035933c0d0e4e68ce (diff)
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ext4, doc: remove unnecessary escaping
Signed-off-by: Wang Jianjian <wangjianjian3@huawei.com> Link: https://lore.kernel.org/r/20220520022255.2120576-2-wangjianjian3@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Diffstat (limited to 'Documentation/filesystems/ext4')
-rw-r--r--Documentation/filesystems/ext4/attributes.rst68
-rw-r--r--Documentation/filesystems/ext4/bigalloc.rst2
-rw-r--r--Documentation/filesystems/ext4/bitmaps.rst6
-rw-r--r--Documentation/filesystems/ext4/blockgroup.rst30
-rw-r--r--Documentation/filesystems/ext4/blockmap.rst2
-rw-r--r--Documentation/filesystems/ext4/checksums.rst26
-rw-r--r--Documentation/filesystems/ext4/directory.rst166
-rw-r--r--Documentation/filesystems/ext4/eainode.rst10
-rw-r--r--Documentation/filesystems/ext4/group_descr.rst126
-rw-r--r--Documentation/filesystems/ext4/ifork.rst60
-rw-r--r--Documentation/filesystems/ext4/inlinedata.rst8
-rw-r--r--Documentation/filesystems/ext4/inodes.rst306
-rw-r--r--Documentation/filesystems/ext4/journal.rst214
-rw-r--r--Documentation/filesystems/ext4/mmp.rst36
-rw-r--r--Documentation/filesystems/ext4/overview.rst2
-rw-r--r--Documentation/filesystems/ext4/special_inodes.rst8
-rw-r--r--Documentation/filesystems/ext4/super.rst550
17 files changed, 810 insertions, 810 deletions
diff --git a/Documentation/filesystems/ext4/attributes.rst b/Documentation/filesystems/ext4/attributes.rst
index 871d2da7a0a9..87814696a65b 100644
--- a/Documentation/filesystems/ext4/attributes.rst
+++ b/Documentation/filesystems/ext4/attributes.rst
@@ -13,8 +13,8 @@ disappeared as of Linux 3.0.
There are two places where extended attributes can be found. The first
place is between the end of each inode entry and the beginning of the
-next inode entry. For example, if inode.i\_extra\_isize = 28 and
-sb.inode\_size = 256, then there are 256 - (128 + 28) = 100 bytes
+next inode entry. For example, if inode.i_extra_isize = 28 and
+sb.inode_size = 256, then there are 256 - (128 + 28) = 100 bytes
available for in-inode extended attribute storage. The second place
where extended attributes can be found is in the block pointed to by
``inode.i_file_acl``. As of Linux 3.11, it is not possible for this
@@ -38,8 +38,8 @@ Extended attributes, when stored after the inode, have a header
- Name
- Description
* - 0x0
- - \_\_le32
- - h\_magic
+ - __le32
+ - h_magic
- Magic number for identification, 0xEA020000. This value is set by the
Linux driver, though e2fsprogs doesn't seem to check it(?)
@@ -55,28 +55,28 @@ The beginning of an extended attribute block is in
- Name
- Description
* - 0x0
- - \_\_le32
- - h\_magic
+ - __le32
+ - h_magic
- Magic number for identification, 0xEA020000.
* - 0x4
- - \_\_le32
- - h\_refcount
+ - __le32
+ - h_refcount
- Reference count.
* - 0x8
- - \_\_le32
- - h\_blocks
+ - __le32
+ - h_blocks
- Number of disk blocks used.
* - 0xC
- - \_\_le32
- - h\_hash
+ - __le32
+ - h_hash
- Hash value of all attributes.
* - 0x10
- - \_\_le32
- - h\_checksum
+ - __le32
+ - h_checksum
- Checksum of the extended attribute block.
* - 0x14
- - \_\_u32
- - h\_reserved[3]
+ - __u32
+ - h_reserved[3]
- Zero.
The checksum is calculated against the FS UUID, the 64-bit block number
@@ -100,46 +100,46 @@ Attributes stored inside an inode do not need be stored in sorted order.
- Name
- Description
* - 0x0
- - \_\_u8
- - e\_name\_len
+ - __u8
+ - e_name_len
- Length of name.
* - 0x1
- - \_\_u8
- - e\_name\_index
+ - __u8
+ - e_name_index
- Attribute name index. There is a discussion of this below.
* - 0x2
- - \_\_le16
- - e\_value\_offs
+ - __le16
+ - e_value_offs
- Location of this attribute's value on the disk block where it is stored.
Multiple attributes can share the same value. For an inode attribute
this value is relative to the start of the first entry; for a block this
value is relative to the start of the block (i.e. the header).
* - 0x4
- - \_\_le32
- - e\_value\_inum
+ - __le32
+ - e_value_inum
- The inode where the value is stored. Zero indicates the value is in the
same block as this entry. This field is only used if the
- INCOMPAT\_EA\_INODE feature is enabled.
+ INCOMPAT_EA_INODE feature is enabled.
* - 0x8
- - \_\_le32
- - e\_value\_size
+ - __le32
+ - e_value_size
- Length of attribute value.
* - 0xC
- - \_\_le32
- - e\_hash
+ - __le32
+ - e_hash
- Hash value of attribute name and attribute value. The kernel doesn't
update the hash for in-inode attributes, so for that case this value
must be zero, because e2fsck validates any non-zero hash regardless of
where the xattr lives.
* - 0x10
- char
- - e\_name[e\_name\_len]
+ - e_name[e_name_len]
- Attribute name. Does not include trailing NULL.
Attribute values can follow the end of the entry table. There appears to
be a requirement that they be aligned to 4-byte boundaries. The values
are stored starting at the end of the block and grow towards the
-xattr\_header/xattr\_entry table. When the two collide, the overflow is
+xattr_header/xattr_entry table. When the two collide, the overflow is
put into a separate disk block. If the disk block fills up, the
filesystem returns -ENOSPC.
@@ -167,15 +167,15 @@ the key name. Here is a map of name index values to key prefixes:
* - 1
- “user.”
* - 2
- - “system.posix\_acl\_access”
+ - “system.posix_acl_access”
* - 3
- - “system.posix\_acl\_default”
+ - “system.posix_acl_default”
* - 4
- “trusted.”
* - 6
- “security.”
* - 7
- - “system.” (inline\_data only?)
+ - “system.” (inline_data only?)
* - 8
- “system.richacl” (SuSE kernels only?)
diff --git a/Documentation/filesystems/ext4/bigalloc.rst b/Documentation/filesystems/ext4/bigalloc.rst
index 72075aa608e4..976a180b209c 100644
--- a/Documentation/filesystems/ext4/bigalloc.rst
+++ b/Documentation/filesystems/ext4/bigalloc.rst
@@ -23,7 +23,7 @@ means that a block group addresses 32 gigabytes instead of 128 megabytes,
also shrinking the amount of file system overhead for metadata.
The administrator can set a block cluster size at mkfs time (which is
-stored in the s\_log\_cluster\_size field in the superblock); from then
+stored in the s_log_cluster_size field in the superblock); from then
on, the block bitmaps track clusters, not individual blocks. This means
that block groups can be several gigabytes in size (instead of just
128MiB); however, the minimum allocation unit becomes a cluster, not a
diff --git a/Documentation/filesystems/ext4/bitmaps.rst b/Documentation/filesystems/ext4/bitmaps.rst
index c7546dbc197a..91c45d86e9bb 100644
--- a/Documentation/filesystems/ext4/bitmaps.rst
+++ b/Documentation/filesystems/ext4/bitmaps.rst
@@ -9,15 +9,15 @@ group.
The inode bitmap records which entries in the inode table are in use.
As with most bitmaps, one bit represents the usage status of one data
-block or inode table entry. This implies a block group size of 8 \*
-number\_of\_bytes\_in\_a\_logical\_block.
+block or inode table entry. This implies a block group size of 8 *
+number_of_bytes_in_a_logical_block.
NOTE: If ``BLOCK_UNINIT`` is set for a given block group, various parts
of the kernel and e2fsprogs code pretends that the block bitmap contains
zeros (i.e. all blocks in the group are free). However, it is not
necessarily the case that no blocks are in use -- if ``meta_bg`` is set,
the bitmaps and group descriptor live inside the group. Unfortunately,
-ext2fs\_test\_block\_bitmap2() will return '0' for those locations,
+ext2fs_test_block_bitmap2() will return '0' for those locations,
which produces confusing debugfs output.
Inode Table
diff --git a/Documentation/filesystems/ext4/blockgroup.rst b/Documentation/filesystems/ext4/blockgroup.rst
index d5d652addce5..46d78f860623 100644
--- a/Documentation/filesystems/ext4/blockgroup.rst
+++ b/Documentation/filesystems/ext4/blockgroup.rst
@@ -56,39 +56,39 @@ established that the super block and the group descriptor table, if
present, will be at the beginning of the block group. The bitmaps and
the inode table can be anywhere, and it is quite possible for the
bitmaps to come after the inode table, or for both to be in different
-groups (flex\_bg). Leftover space is used for file data blocks, indirect
+groups (flex_bg). Leftover space is used for file data blocks, indirect
block maps, extent tree blocks, and extended attributes.
Flexible Block Groups
---------------------
Starting in ext4, there is a new feature called flexible block groups
-(flex\_bg). In a flex\_bg, several block groups are tied together as one
+(flex_bg). In a flex_bg, several block groups are tied together as one
logical block group; the bitmap spaces and the inode table space in the
-first block group of the flex\_bg are expanded to include the bitmaps
-and inode tables of all other block groups in the flex\_bg. For example,
-if the flex\_bg size is 4, then group 0 will contain (in order) the
+first block group of the flex_bg are expanded to include the bitmaps
+and inode tables of all other block groups in the flex_bg. For example,
+if the flex_bg size is 4, then group 0 will contain (in order) the
superblock, group descriptors, data block bitmaps for groups 0-3, inode
bitmaps for groups 0-3, inode tables for groups 0-3, and the remaining
space in group 0 is for file data. The effect of this is to group the
block group metadata close together for faster loading, and to enable
large files to be continuous on disk. Backup copies of the superblock
and group descriptors are always at the beginning of block groups, even
-if flex\_bg is enabled. The number of block groups that make up a
-flex\_bg is given by 2 ^ ``sb.s_log_groups_per_flex``.
+if flex_bg is enabled. The number of block groups that make up a
+flex_bg is given by 2 ^ ``sb.s_log_groups_per_flex``.
Meta Block Groups
-----------------
-Without the option META\_BG, for safety concerns, all block group
+Without the option META_BG, for safety concerns, all block group
descriptors copies are kept in the first block group. Given the default
128MiB(2^27 bytes) block group size and 64-byte group descriptors, ext4
can have at most 2^27/64 = 2^21 block groups. This limits the entire
filesystem size to 2^21 * 2^27 = 2^48bytes or 256TiB.
The solution to this problem is to use the metablock group feature
-(META\_BG), which is already in ext3 for all 2.6 releases. With the
-META\_BG feature, ext4 filesystems are partitioned into many metablock
+(META_BG), which is already in ext3 for all 2.6 releases. With the
+META_BG feature, ext4 filesystems are partitioned into many metablock
groups. Each metablock group is a cluster of block groups whose group
descriptor structures can be stored in a single disk block. For ext4
filesystems with 4 KB block size, a single metablock group partition
@@ -110,7 +110,7 @@ bytes, a meta-block group contains 32 block groups for filesystems with
a 1KB block size, and 128 block groups for filesystems with a 4KB
blocksize. Filesystems can either be created using this new block group
descriptor layout, or existing filesystems can be resized on-line, and
-the field s\_first\_meta\_bg in the superblock will indicate the first
+the field s_first_meta_bg in the superblock will indicate the first
block group using this new layout.
Please see an important note about ``BLOCK_UNINIT`` in the section about
@@ -121,15 +121,15 @@ Lazy Block Group Initialization
A new feature for ext4 are three block group descriptor flags that
enable mkfs to skip initializing other parts of the block group
-metadata. Specifically, the INODE\_UNINIT and BLOCK\_UNINIT flags mean
+metadata. Specifically, the INODE_UNINIT and BLOCK_UNINIT flags mean
that the inode and block bitmaps for that group can be calculated and
therefore the on-disk bitmap blocks are not initialized. This is
generally the case for an empty block group or a block group containing
-only fixed-location block group metadata. The INODE\_ZEROED flag means
+only fixed-location block group metadata. The INODE_ZEROED flag means
that the inode table has been initialized; mkfs will unset this flag and
rely on the kernel to initialize the inode tables in the background.
By not writing zeroes to the bitmaps and inode table, mkfs time is
-reduced considerably. Note the feature flag is RO\_COMPAT\_GDT\_CSUM,
-but the dumpe2fs output prints this as “uninit\_bg”. They are the same
+reduced considerably. Note the feature flag is RO_COMPAT_GDT_CSUM,
+but the dumpe2fs output prints this as “uninit_bg”. They are the same
thing.
diff --git a/Documentation/filesystems/ext4/blockmap.rst b/Documentation/filesystems/ext4/blockmap.rst
index 30e25750d88a..2bd990402a5c 100644
--- a/Documentation/filesystems/ext4/blockmap.rst
+++ b/Documentation/filesystems/ext4/blockmap.rst
@@ -1,7 +1,7 @@
.. SPDX-License-Identifier: GPL-2.0
+---------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
-| i.i\_block Offset | Where It Points |
+| i.i_block Offset | Where It Points |
+=====================+==============================================================================================================================================================================================================================+
| 0 to 11 | Direct map to file blocks 0 to 11. |
+---------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
diff --git a/Documentation/filesystems/ext4/checksums.rst b/Documentation/filesystems/ext4/checksums.rst
index 5519e253810d..e232749daf5f 100644
--- a/Documentation/filesystems/ext4/checksums.rst
+++ b/Documentation/filesystems/ext4/checksums.rst
@@ -4,7 +4,7 @@ Checksums
---------
Starting in early 2012, metadata checksums were added to all major ext4
-and jbd2 data structures. The associated feature flag is metadata\_csum.
+and jbd2 data structures. The associated feature flag is metadata_csum.
The desired checksum algorithm is indicated in the superblock, though as
of October 2012 the only supported algorithm is crc32c. Some data
structures did not have space to fit a full 32-bit checksum, so only the
@@ -20,7 +20,7 @@ encounters directory blocks that lack sufficient empty space to add a
checksum, it will request that you run ``e2fsck -D`` to have the
directories rebuilt with checksums. This has the added benefit of
removing slack space from the directory files and rebalancing the htree
-indexes. If you \_ignore\_ this step, your directories will not be
+indexes. If you _ignore_ this step, your directories will not be
protected by a checksum!
The following table describes the data elements that go into each type
@@ -35,39 +35,39 @@ of checksum. The checksum function is whatever the superblock describes
- Length
- Ingredients
* - Superblock
- - \_\_le32
+ - __le32
- The entire superblock up to the checksum field. The UUID lives inside
the superblock.
* - MMP
- - \_\_le32
+ - __le32
- UUID + the entire MMP block up to the checksum field.
* - Extended Attributes
- - \_\_le32
+ - __le32
- UUID + the entire extended attribute block. The checksum field is set to
zero.
* - Directory Entries
- - \_\_le32
+ - __le32
- UUID + inode number + inode generation + the directory block up to the
fake entry enclosing the checksum field.
* - HTREE Nodes
- - \_\_le32
+ - __le32
- UUID + inode number + inode generation + all valid extents + HTREE tail.
The checksum field is set to zero.
* - Extents
- - \_\_le32
+ - __le32
- UUID + inode number + inode generation + the entire extent block up to
the checksum field.
* - Bitmaps
- - \_\_le32 or \_\_le16
+ - __le32 or __le16
- UUID + the entire bitmap. Checksums are stored in the group descriptor,
and truncated if the group descriptor size is 32 bytes (i.e. ^64bit)
* - Inodes
- - \_\_le32
+ - __le32
- UUID + inode number + inode generation + the entire inode. The checksum
field is set to zero. Each inode has its own checksum.
* - Group Descriptors
- - \_\_le16
- - If metadata\_csum, then UUID + group number + the entire descriptor;
- else if gdt\_csum, then crc16(UUID + group number + the entire
+ - __le16
+ - If metadata_csum, then UUID + group number + the entire descriptor;
+ else if gdt_csum, then crc16(UUID + group number + the entire
descriptor). In all cases, only the lower 16 bits are stored.
diff --git a/Documentation/filesystems/ext4/directory.rst b/Documentation/filesystems/ext4/directory.rst
index 55f618b37144..6eece8e31df8 100644
--- a/Documentation/filesystems/ext4/directory.rst
+++ b/Documentation/filesystems/ext4/directory.rst
@@ -42,24 +42,24 @@ is at most 263 bytes long, though on disk you'll need to reference
- Name
- Description
* - 0x0
- - \_\_le32
+ - __le32
- inode
- Number of the inode that this directory entry points to.
* - 0x4
- - \_\_le16
- - rec\_len
+ - __le16
+ - rec_len
- Length of this directory entry. Must be a multiple of 4.
* - 0x6
- - \_\_le16
- - name\_len
+ - __le16
+ - name_len
- Length of the file name.
* - 0x8
- char
- - name[EXT4\_NAME\_LEN]
+ - name[EXT4_NAME_LEN]
- File name.
Since file names cannot be longer than 255 bytes, the new directory
-entry format shortens the name\_len field and uses the space for a file
+entry format shortens the name_len field and uses the space for a file
type flag, probably to avoid having to load every inode during directory
tree traversal. This format is ``ext4_dir_entry_2``, which is at most
263 bytes long, though on disk you'll need to reference
@@ -74,24 +74,24 @@ tree traversal. This format is ``ext4_dir_entry_2``, which is at most
- Name
- Description
* - 0x0
- - \_\_le32
+ - __le32
- inode
- Number of the inode that this directory entry points to.
* - 0x4
- - \_\_le16
- - rec\_len
+ - __le16
+ - rec_len
- Length of this directory entry.
* - 0x6
- - \_\_u8
- - name\_len
+ - __u8
+ - name_len
- Length of the file name.
* - 0x7
- - \_\_u8
- - file\_type
+ - __u8
+ - file_type
- File type code, see ftype_ table below.
* - 0x8
- char
- - name[EXT4\_NAME\_LEN]
+ - name[EXT4_NAME_LEN]
- File name.
.. _ftype:
@@ -137,19 +137,19 @@ entry uses this extension, it may be up to 271 bytes.
- Name
- Description
* - 0x0
- - \_\_le32
+ - __le32
- hash
- The hash of the directory name
* - 0x4
- - \_\_le32
- - minor\_hash
+ - __le32
+ - minor_hash
- The minor hash of the directory name
In order to add checksums to these classic directory blocks, a phony
``struct ext4_dir_entry`` is placed at the end of each leaf block to
hold the checksum. The directory entry is 12 bytes long. The inode
-number and name\_len fields are set to zero to fool old software into
+number and name_len fields are set to zero to fool old software into
ignoring an apparently empty directory entry, and the checksum is stored
in the place where the name normally goes. The structure is
``struct ext4_dir_entry_tail``:
@@ -163,24 +163,24 @@ in the place where the name normally goes. The structure is
- Name
- Description
* - 0x0
- - \_\_le32
- - det\_reserved\_zero1
+ - __le32
+ - det_reserved_zero1
- Inode number, which must be zero.
* - 0x4
- - \_\_le16
- - det\_rec\_len
+ - __le16
+ - det_rec_len
- Length of this directory entry, which must be 12.
* - 0x6
- - \_\_u8
- - det\_reserved\_zero2
+ - __u8
+ - det_reserved_zero2
- Length of the file name, which must be zero.
* - 0x7
- - \_\_u8
- - det\_reserved\_ft
+ - __u8
+ - det_reserved_ft
- File type, which must be 0xDE.
* - 0x8
- - \_\_le32
- - det\_checksum
+ - __le32
+ - det_checksum
- Directory leaf block checksum.
The leaf directory block checksum is calculated against the FS UUID, the
@@ -194,7 +194,7 @@ Hash Tree Directories
A linear array of directory entries isn't great for performance, so a
new feature was added to ext3 to provide a faster (but peculiar)
balanced tree keyed off a hash of the directory entry name. If the
-EXT4\_INDEX\_FL (0x1000) flag is set in the inode, this directory uses a
+EXT4_INDEX_FL (0x1000) flag is set in the inode, this directory uses a
hashed btree (htree) to organize and find directory entries. For
backwards read-only compatibility with ext2, this tree is actually
hidden inside the directory file, masquerading as “empty” directory data
@@ -206,14 +206,14 @@ rest of the directory block is empty so that it moves on.
The root of the tree always lives in the first data block of the
directory. By ext2 custom, the '.' and '..' entries must appear at the
beginning of this first block, so they are put here as two
-``struct ext4_dir_entry_2``\ s and not stored in the tree. The rest of
+``struct ext4_dir_entry_2`` s and not stored in the tree. The rest of
the root node contains metadata about the tree and finally a hash->block
map to find nodes that are lower in the htree. If
``dx_root.info.indirect_levels`` is non-zero then the htree has two
levels; the data block pointed to by the root node's map is an interior
node, which is indexed by a minor hash. Interior nodes in this tree
contains a zeroed out ``struct ext4_dir_entry_2`` followed by a
-minor\_hash->block map to find leafe nodes. Leaf nodes contain a linear
+minor_hash->block map to find leafe nodes. Leaf nodes contain a linear
array of all ``struct ext4_dir_entry_2``; all of these entries
(presumably) hash to the same value. If there is an overflow, the
entries simply overflow into the next leaf node, and the
@@ -245,83 +245,83 @@ of a data block:
- Name
- Description
* - 0x0
- - \_\_le32
+ - __le32
- dot.inode
- inode number of this directory.
* - 0x4
- - \_\_le16
- - dot.rec\_len
+ - __le16
+ - dot.rec_len
- Length of this record, 12.
* - 0x6
- u8
- - dot.name\_len
+ - dot.name_len
- Length of the name, 1.
* - 0x7
- u8
- - dot.file\_type
+ - dot.file_type
- File type of this entry, 0x2 (directory) (if the feature flag is set).
* - 0x8
- char
- dot.name[4]
- - “.\\0\\0\\0”
+ - “.\0\0\0”
* - 0xC
- - \_\_le32
+ - __le32
- dotdot.inode
- inode number of parent directory.
* - 0x10
- - \_\_le16
- - dotdot.rec\_len
- - block\_size - 12. The record length is long enough to cover all htree
+ - __le16
+ - dotdot.rec_len
+ - block_size - 12. The record length is long enough to cover all htree
data.
* - 0x12
- u8
- - dotdot.name\_len
+ - dotdot.name_len
- Length of the name, 2.
* - 0x13
- u8
- - dotdot.file\_type
+ - dotdot.file_type
- File type of this entry, 0x2 (directory) (if the feature flag is set).
* - 0x14
- char
- - dotdot\_name[4]
- - “..\\0\\0”
+ - dotdot_name[4]
+ - “..\0\0”
* - 0x18
- - \_\_le32
- - struct dx\_root\_info.reserved\_zero
+ - __le32
+ - struct dx_root_info.reserved_zero
- Zero.
* - 0x1C
- u8
- - struct dx\_root\_info.hash\_version
+ - struct dx_root_info.hash_version
- Hash type, see dirhash_ table below.
* - 0x1D
- u8
- - struct dx\_root\_info.info\_length
+ - struct dx_root_info.info_length
- Length of the tree information, 0x8.
* - 0x1E
- u8
- - struct dx\_root\_info.indirect\_levels
- - Depth of the htree. Cannot be larger than 3 if the INCOMPAT\_LARGEDIR
+ - struct dx_root_info.indirect_levels
+ - Depth of the htree. Cannot be larger than 3 if the INCOMPAT_LARGEDIR
feature is set; cannot be larger than 2 otherwise.
* - 0x1F
- u8
- - struct dx\_root\_info.unused\_flags
+ - struct dx_root_info.unused_flags
-
* - 0x20
- - \_\_le16
+ - __le16
- limit
- - Maximum number of dx\_entries that can follow this header, plus 1 for
+ - Maximum number of dx_entries that can follow this header, plus 1 for
the header itself.
* - 0x22
- - \_\_le16
+ - __le16
- count
- - Actual number of dx\_entries that follow this header, plus 1 for the
+ - Actual number of dx_entries that follow this header, plus 1 for the
header itself.
* - 0x24
- - \_\_le32
+ - __le32
- block
- The block number (within the directory file) that goes with hash=0.
* - 0x28
- - struct dx\_entry
+ - struct dx_entry
- entries[0]
- As many 8-byte ``struct dx_entry`` as fits in the rest of the data block.
@@ -362,38 +362,38 @@ also the full length of a data block:
- Name
- Description
* - 0x0
- - \_\_le32
+ - __le32
- fake.inode
- Zero, to make it look like this entry is not in use.
* - 0x4
- - \_\_le16
- - fake.rec\_len
- - The size of the block, in order to hide all of the dx\_node data.
+ - __le16
+ - fake.rec_len
+ - The size of the block, in order to hide all of the dx_node data.
* - 0x6
- u8
- - name\_len
+ - name_len
- Zero. There is no name for this “unused” directory entry.
* - 0x7
- u8
- - file\_type
+ - file_type
- Zero. There is no file type for this “unused” directory entry.
* - 0x8
- - \_\_le16
+ - __le16
- limit
- - Maximum number of dx\_entries that can follow this header, plus 1 for
+ - Maximum number of dx_entries that can follow this header, plus 1 for
the header itself.
* - 0xA
- - \_\_le16
+ - __le16
- count
- - Actual number of dx\_entries that follow this header, plus 1 for the
+ - Actual number of dx_entries that follow this header, plus 1 for the
header itself.
* - 0xE
- - \_\_le32
+ - __le32
- block
- The block number (within the directory file) that goes with the lowest
hash value of this block. This value is stored in the parent block.
* - 0x12
- - struct dx\_entry
+ - struct dx_entry
- entries[0]
- As many 8-byte ``struct dx_entry`` as fits in the rest of the data block.
@@ -410,11 +410,11 @@ long:
- Name
- Description
* - 0x0
- - \_\_le32
+ - __le32
- hash
- Hash code.
* - 0x4
- - \_\_le32
+ - __le32
- block
- Block number (within the directory file, not filesystem blocks) of the
next node in the htree.
@@ -423,13 +423,13 @@ long:
author.)
If metadata checksums are enabled, the last 8 bytes of the directory
-block (precisely the length of one dx\_entry) are used to store a
+block (precisely the length of one dx_entry) are used to store a
``struct dx_tail``, which contains the checksum. The ``limit`` and
-``count`` entries in the dx\_root/dx\_node structures are adjusted as
-necessary to fit the dx\_tail into the block. If there is no space for
-the dx\_tail, the user is notified to run e2fsck -D to rebuild the
+``count`` entries in the dx_root/dx_node structures are adjusted as
+necessary to fit the dx_tail into the block. If there is no space for
+the dx_tail, the user is notified to run e2fsck -D to rebuild the
directory index (which will ensure that there's space for the checksum.
-The dx\_tail structure is 8 bytes long and looks like this:
+The dx_tail structure is 8 bytes long and looks like this:
.. list-table::
:widths: 8 8 24 40
@@ -441,13 +441,13 @@ The dx\_tail structure is 8 bytes long and looks like this:
- Description
* - 0x0
- u32
- - dt\_reserved
+ - dt_reserved
- Zero.
* - 0x4
- - \_\_le32
- - dt\_checksum
+ - __le32
+ - dt_checksum
- Checksum of the htree directory block.
The checksum is calculated against the FS UUID, the htree index header
-(dx\_root or dx\_node), all of the htree indices (dx\_entry) that are in
-use, and the tail block (dx\_tail).
+(dx_root or dx_node), all of the htree indices (dx_entry) that are in
+use, and the tail block (dx_tail).
diff --git a/Documentation/filesystems/ext4/eainode.rst b/Documentation/filesystems/ext4/eainode.rst
index ecc0d01a0a72..7a2ef26b064a 100644
--- a/Documentation/filesystems/ext4/eainode.rst
+++ b/Documentation/filesystems/ext4/eainode.rst
@@ -5,14 +5,14 @@ Large Extended Attribute Values
To enable ext4 to store extended attribute values that do not fit in the
inode or in the single extended attribute block attached to an inode,
-the EA\_INODE feature allows us to store the value in the data blocks of
+the EA_INODE feature allows us to store the value in the data blocks of
a regular file inode. This “EA inode” is linked only from the extended
attribute name index and must not appear in a directory entry. The
-inode's i\_atime field is used to store a checksum of the xattr value;
-and i\_ctime/i\_version store a 64-bit reference count, which enables
+inode's i_atime field is used to store a checksum of the xattr value;
+and i_ctime/i_version store a 64-bit reference count, which enables
sharing of large xattr values between multiple owning inodes. For
backward compatibility with older versions of this feature, the
-i\_mtime/i\_generation *may* store a back-reference to the inode number
-and i\_generation of the **one** owning inode (in cases where the EA
+i_mtime/i_generation *may* store a back-reference to the inode number
+and i_generation of the **one** owning inode (in cases where the EA
inode is not referenced by multiple inodes) to verify that the EA inode
is the correct one being accessed.
diff --git a/Documentation/filesystems/ext4/group_descr.rst b/Documentation/filesystems/ext4/group_descr.rst
index 7ba6114e7f5c..392ec44f8fb0 100644
--- a/Documentation/filesystems/ext4/group_descr.rst
+++ b/Documentation/filesystems/ext4/group_descr.rst
@@ -7,34 +7,34 @@ Each block group on the filesystem has one of these descriptors
associated with it. As noted in the Layout section above, the group
descriptors (if present) are the second item in the block group. The
standard configuration is for each block group to contain a full copy of
-the block group descriptor table unless the sparse\_super feature flag
+the block group descriptor table unless the sparse_super feature flag
is set.
Notice how the group descriptor records the location of both bitmaps and
the inode table (i.e. they can float). This means that within a block
group, the only data structures with fixed locations are the superblock
-and the group descriptor table. The flex\_bg mechanism uses this
+and the group descriptor table. The flex_bg mechanism uses this
property to group several block groups into a flex group and lay out all
of the groups' bitmaps and inode tables into one long run in