f6753df35c
Before this patch, several functions in rgrp.c checked the value of rgd->rd_free_clone. That does not take into account blocks that were reserved by a multi-block reservation. This causes a problem when space gets tight in the file system. For example, when function gfs2_inplace_reserve checks to see if a rgrp has enough blocks to satisfy the request, it can accept a rgrp that it should reject because, although there are enough blocks to satisfy the request _now_, those blocks may be reserved for another running process. A second problem with this occurs when we've reserved the remaining blocks in an rgrp: function rg_mblk_search() can reject an rgrp improperly because it calculates: u32 free_blocks = rgd->rd_free_clone - rgd->rd_reserved; But rd_reserved includes blocks that the current process just reserved in its own call to inplace_reserve. For example, it can reserve the last 128 blocks of an rgrp, then reject that same rgrp because the above calculates out to free_blocks = 0; Consequences include, but are not limited to, (1) leaving holes, and thus increasing file system fragmentation, and (2) reporting file system is full long before it actually is. This patch introduces a new function, rgd_free, which returns the number of clone-free blocks (blocks that are truly free as opposed to blocks that are still being used because an unlinked file is still open) minus the number of blocks reserved by processes, but not counting the blocks we ourselves reserved (because obviously we need to allocate them). Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> |
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| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
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| COPYING | ||
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| Kbuild | ||
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| Makefile | ||
| README | ||
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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.