24331050a3
Prior to ztailpacking feature, it's enough that each lcluster has
two pclusters at most, and the last pcluster should be turned into
an uncompressed pcluster when necessary. For example,
_________________________________________________
|_ pcluster n-2 _|_ pcluster n-1 _|____ EOFed ____|
which should be converted into:
_________________________________________________
|_ pcluster n-2 _|_ pcluster n-1 (uncompressed)' _|
That is fine since either pcluster n-1 or (uncompressed)' takes one
physical block.
However, after ztailpacking was supported, the game is changed since
the last pcluster can be inlined now. And such case above is quite
common for inlining small files. Therefore, in order to inline more
effectively, special EOF lclusters are now supported which can have
three parts at most, as illustrated below:
_________________________________________________
|_ pcluster n-2 _|_ pcluster n-1 _|____ EOFed ____|
^ i_size
Actually similar code exists in Yue Hu's original patchset [1], but I
removed this part on purpose. After evaluating more real cases with
small files, I've changed my mind.
[1] https://lore.kernel.org/r/20211215094449.15162-1-huyue2@yulong.com
Link: https://lore.kernel.org/r/20220203190203.30794-1-xiang@kernel.org
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.