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-rw-r--r--Documentation/filesystems/ext4/ifork.rst60
1 files changed, 30 insertions, 30 deletions
diff --git a/Documentation/filesystems/ext4/ifork.rst b/Documentation/filesystems/ext4/ifork.rst
index b9816d5a896b..dc31f505e6c8 100644
--- a/Documentation/filesystems/ext4/ifork.rst
+++ b/Documentation/filesystems/ext4/ifork.rst
@@ -1,6 +1,6 @@
.. SPDX-License-Identifier: GPL-2.0
-The Contents of inode.i\_block
+The Contents of inode.i_block
------------------------------
Depending on the type of file an inode describes, the 60 bytes of
@@ -47,7 +47,7 @@ In ext4, the file to logical block map has been replaced with an extent
tree. Under the old scheme, allocating a contiguous run of 1,000 blocks
requires an indirect block to map all 1,000 entries; with extents, the
mapping is reduced to a single ``struct ext4_extent`` with
-``ee_len = 1000``. If flex\_bg is enabled, it is possible to allocate
+``ee_len = 1000``. If flex_bg is enabled, it is possible to allocate
very large files with a single extent, at a considerable reduction in
metadata block use, and some improvement in disk efficiency. The inode
must have the extents flag (0x80000) flag set for this feature to be in
@@ -76,28 +76,28 @@ which is 12 bytes long:
- Name
- Description
* - 0x0
- - \_\_le16
- - eh\_magic
+ - __le16
+ - eh_magic
- Magic number, 0xF30A.
* - 0x2
- - \_\_le16
- - eh\_entries
+ - __le16
+ - eh_entries
- Number of valid entries following the header.
* - 0x4
- - \_\_le16
- - eh\_max
+ - __le16
+ - eh_max
- Maximum number of entries that could follow the header.
* - 0x6
- - \_\_le16
- - eh\_depth
+ - __le16
+ - eh_depth
- Depth of this extent node in the extent tree. 0 = this extent node
points to data blocks; otherwise, this extent node points to other
extent nodes. The extent tree can be at most 5 levels deep: a logical
block number can be at most ``2^32``, and the smallest ``n`` that
satisfies ``4*(((blocksize - 12)/12)^n) >= 2^32`` is 5.
* - 0x8
- - \_\_le32
- - eh\_generation
+ - __le32
+ - eh_generation
- Generation of the tree. (Used by Lustre, but not standard ext4).
Internal nodes of the extent tree, also known as index nodes, are
@@ -112,22 +112,22 @@ recorded as ``struct ext4_extent_idx``, and are 12 bytes long:
- Name
- Description
* - 0x0
- - \_\_le32
- - ei\_block
+ - __le32
+ - ei_block
- This index node covers file blocks from 'block' onward.
* - 0x4
- - \_\_le32
- - ei\_leaf\_lo
+ - __le32
+ - ei_leaf_lo
- Lower 32-bits of the block number of the extent node that is the next
level lower in the tree. The tree node pointed to can be either another
internal node or a leaf node, described below.
* - 0x8
- - \_\_le16
- - ei\_leaf\_hi
+ - __le16
+ - ei_leaf_hi
- Upper 16-bits of the previous field.
* - 0xA
- - \_\_u16
- - ei\_unused
+ - __u16
+ - ei_unused
-
Leaf nodes of the extent tree are recorded as ``struct ext4_extent``,
@@ -142,24 +142,24 @@ and are also 12 bytes long:
- Name
- Description
* - 0x0
- - \_\_le32
- - ee\_block
+ - __le32
+ - ee_block
- First file block number that this extent covers.
* - 0x4
- - \_\_le16
- - ee\_len
+ - __le16
+ - ee_len
- Number of blocks covered by extent. If the value of this field is <=
32768, the extent is initialized. If the value of the field is > 32768,
the extent is uninitialized and the actual extent length is ``ee_len`` -
32768. Therefore, the maximum length of a initialized extent is 32768
blocks, and the maximum length of an uninitialized extent is 32767.
* - 0x6
- - \_\_le16
- - ee\_start\_hi
+ - __le16
+ - ee_start_hi
- Upper 16-bits of the block number to which this extent points.
* - 0x8
- - \_\_le32
- - ee\_start\_lo
+ - __le32
+ - ee_start_lo
- Lower 32-bits of the block number to which this extent points.
Prior to the introduction of metadata checksums, the extent header +
@@ -182,8 +182,8 @@ including) the checksum itself.
- Name
- Description
* - 0x0
- - \_\_le32
- - eb\_checksum
+ - __le32
+ - eb_checksum
- Checksum of the extent block, crc32c(uuid+inum+igeneration+extentblock)
Inline Data