[PATCH 1/2] erofs: fix broken illustration in documentation
Gao Xiang
xiang at kernel.org
Tue May 11 02:25:05 AEST 2021
From: Gao Xiang <hsiangkao at redhat.com>
Illustration was broken after ReST conversion by accident.
(checked by 'make SPHINXDIRS="filesystems" htmldocs')
Fixes: e66d8631ddb3 ("docs: filesystems: convert erofs.txt to ReST")
Cc: Mauro Carvalho Chehab <mchehab+huawei at kernel.org>
Signed-off-by: Gao Xiang <hsiangkao at redhat.com>
---
Documentation/filesystems/erofs.rst | 119 ++++++++++++++--------------
1 file changed, 59 insertions(+), 60 deletions(-)
diff --git a/Documentation/filesystems/erofs.rst b/Documentation/filesystems/erofs.rst
index bf145171c2bf..869b183ff215 100644
--- a/Documentation/filesystems/erofs.rst
+++ b/Documentation/filesystems/erofs.rst
@@ -113,31 +113,31 @@ may not. All metadatas can be now observed in two different spaces (views):
::
- |-> aligned with 8B
- |-> followed closely
- + meta_blkaddr blocks |-> another slot
- _____________________________________________________________________
- | ... | inode | xattrs | extents | data inline | ... | inode ...
- |________|_______|(optional)|(optional)|__(optional)_|_____|__________
- |-> aligned with the inode slot size
- . .
- . .
- . .
- . .
- . .
- . .
- .____________________________________________________|-> aligned with 4B
- | xattr_ibody_header | shared xattrs | inline xattrs |
- |____________________|_______________|_______________|
- |-> 12 bytes <-|->x * 4 bytes<-| .
- . . .
- . . .
- . . .
- ._______________________________.______________________.
- | id | id | id | id | ... | id | ent | ... | ent| ... |
- |____|____|____|____|______|____|_____|_____|____|_____|
- |-> aligned with 4B
- |-> aligned with 4B
+ |-> aligned with 8B
+ |-> followed closely
+ + meta_blkaddr blocks |-> another slot
+ _____________________________________________________________________
+ | ... | inode | xattrs | extents | data inline | ... | inode ...
+ |________|_______|(optional)|(optional)|__(optional)_|_____|__________
+ |-> aligned with the inode slot size
+ . .
+ . .
+ . .
+ . .
+ . .
+ . .
+ .____________________________________________________|-> aligned with 4B
+ | xattr_ibody_header | shared xattrs | inline xattrs |
+ |____________________|_______________|_______________|
+ |-> 12 bytes <-|->x * 4 bytes<-| .
+ . . .
+ . . .
+ . . .
+ ._______________________________.______________________.
+ | id | id | id | id | ... | id | ent | ... | ent| ... |
+ |____|____|____|____|______|____|_____|_____|____|_____|
+ |-> aligned with 4B
+ |-> aligned with 4B
Inode could be 32 or 64 bytes, which can be distinguished from a common
field which all inode versions have -- i_format::
@@ -175,13 +175,13 @@ may not. All metadatas can be now observed in two different spaces (views):
Each share xattr can also be directly found by the following formula:
xattr offset = xattr_blkaddr * block_size + 4 * xattr_id
- ::
+::
- |-> aligned by 4 bytes
- + xattr_blkaddr blocks |-> aligned with 4 bytes
- _________________________________________________________________________
- | ... | xattr_entry | xattr data | ... | xattr_entry | xattr data ...
- |________|_____________|_____________|_____|______________|_______________
+ |-> aligned by 4 bytes
+ + xattr_blkaddr blocks |-> aligned with 4 bytes
+ _________________________________________________________________________
+ | ... | xattr_entry | xattr data | ... | xattr_entry | xattr data ...
+ |________|_____________|_____________|_____|______________|_______________
Directories
-----------
@@ -193,19 +193,18 @@ algorithm (could refer to the related source code).
::
- ___________________________
- / |
- / ______________|________________
- / / | nameoff1 | nameoffN-1
- ____________.______________._______________v________________v__________
- | dirent | dirent | ... | dirent | filename | filename | ... | filename |
- |___.0___|____1___|_____|___N-1__|____0_____|____1_____|_____|___N-1____|
- \ ^
- \ | * could have
- \ | trailing '\0'
- \________________________| nameoff0
-
- Directory block
+ ___________________________
+ / |
+ / ______________|________________
+ / / | nameoff1 | nameoffN-1
+ ____________.______________._______________v________________v__________
+ | dirent | dirent | ... | dirent | filename | filename | ... | filename |
+ |___.0___|____1___|_____|___N-1__|____0_____|____1_____|_____|___N-1____|
+ \ ^
+ \ | * could have
+ \ | trailing '\0'
+ \________________________| nameoff0
+ Directory block
Note that apart from the offset of the first filename, nameoff0 also indicates
the total number of directory entries in this block since it is no need to
@@ -216,22 +215,22 @@ Compression
Currently, EROFS supports 4KB fixed-sized output transparent file compression,
as illustrated below::
- |---- Variant-Length Extent ----|-------- VLE --------|----- VLE -----
- clusterofs clusterofs clusterofs
- | | | logical data
- _________v_______________________________v_____________________v_______________
- ... | . | | . | | . | ...
- ____|____.________|_____________|________.____|_____________|__.__________|____
- |-> cluster <-|-> cluster <-|-> cluster <-|-> cluster <-|-> cluster <-|
- size size size size size
- . . . .
- . . . .
- . . . .
- _______._____________._____________._____________._____________________
- ... | | | | ... physical data
- _______|_____________|_____________|_____________|_____________________
- |-> cluster <-|-> cluster <-|-> cluster <-|
- size size size
+ |<- variable-sized extent ->|<- VLE ->|
+ clusterofs clusterofs clusterofs
+ | | |
+ _________v_________________________________v_______________________v________
+ ... | . | | . | | . ...
+ ____|____._________|______________|________.___ _|______________|__.________
+ |-> lcluster <-|-> lcluster <-|-> lcluster <-|-> lcluster <-|
+ size size size size . .
+ . . . .
+ . . . .
+ . . . .
+ _______.______________.______________.______________._________________
+ ... | | | | ...
+ _______|______________|______________|______________|_________________
+ |-> pcluster <-|-> pcluster <-|-> pcluster <-|
+ size size size
Currently each on-disk physical cluster can contain 4KB (un)compressed data
at most. For each logical cluster, there is a corresponding on-disk index to
--
2.20.1
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