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-rw-r--r--Documentation/filesystems/ext4/checksums.rst26
1 files changed, 13 insertions, 13 deletions
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.