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ext4: docs: Take out unneeded escaping 

The new file Documentation/orphan/ext4.rst escapes underscores ("\_")
throughout.  However, RST doesn't actually require that, so the escaping
only succeeds in making the document less readable.  Remove the unneeded
escapes.

Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210902220854.198850-3-corbet@lwn.net
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This commit is contained in:
Jonathan Corbet 2021-09-02 16:08:54 -06:00
parent 91c76340b4
commit 7275423c17
1 changed files with 10 additions and 10 deletions
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20
Documentation/filesystems/ext4/orphan.rst
View File

@ -12,31 +12,31 @@ track the inode as orphan so that in case of crash extra blocks allocated to
the file get truncated.
Traditionally ext4 tracks orphan inodes in a form of single linked list where
superblock contains the inode number of the last orphan inode (s\_last\_orphan
superblock contains the inode number of the last orphan inode (s_last_orphan
field) and then each inode contains inode number of the previously orphaned
inode (we overload i\_dtime inode field for this). However this filesystem
inode (we overload i_dtime inode field for this). However this filesystem
global single linked list is a scalability bottleneck for workloads that result
in heavy creation of orphan inodes. When orphan file feature
(COMPAT\_ORPHAN\_FILE) is enabled, the filesystem has a special inode
(referenced from the superblock through s\_orphan_file_inum) with several
(COMPAT_ORPHAN_FILE) is enabled, the filesystem has a special inode
(referenced from the superblock through s_orphan_file_inum) with several
blocks. Each of these blocks has a structure:
============= ================ =============== ===============================
Offset Type Name Description
============= ================ =============== ===============================
0x0 Array of Orphan inode Each \_\_le32 entry is either
\_\_le32 entries entries empty (0) or it contains
0x0 Array of Orphan inode Each __le32 entry is either
__le32 entries entries empty (0) or it contains
inode number of an orphan
inode.
blocksize-8 \_\_le32 ob\_magic Magic value stored in orphan
blocksize-8 __le32 ob_magic Magic value stored in orphan
block tail (0x0b10ca04)
blocksize-4 \_\_le32 ob\_checksum Checksum of the orphan block.
blocksize-4 __le32 ob_checksum Checksum of the orphan block.
============= ================ =============== ===============================
When a filesystem with orphan file feature is writeably mounted, we set
RO\_COMPAT\_ORPHAN\_PRESENT feature in the superblock to indicate there may
RO_COMPAT_ORPHAN_PRESENT feature in the superblock to indicate there may
be valid orphan entries. In case we see this feature when mounting the
filesystem, we read the whole orphan file and process all orphan inodes found
there as usual. When cleanly unmounting the filesystem we remove the
RO\_COMPAT\_ORPHAN\_PRESENT feature to avoid unnecessary scanning of the orphan
RO_COMPAT_ORPHAN_PRESENT feature to avoid unnecessary scanning of the orphan
file and also make the filesystem fully compatible with older kernels.