e20e174ca1
The collapse range operation can merge extents if two newly adjacent extents are physically contiguous. If the extent count is reduced on a btree format inode, a change to extent format might be necessary. This format change currently occurs as a side effect of the file size update after extents have been shifted for the collapse. This codepath ultimately calls xfs_bunmapi(), which happens to check for and execute the format conversion even if there were no blocks removed from the mapping. While this ultimately puts the inode into the correct state, the fact the format conversion occurs in a separate transaction from the change that called for it is a problem. If an extent shift transaction commits and the filesystem happens to crash before the format conversion, the inode fork is left in a corrupted state after log recovery. The inode fork verifier fails and xfs_repair ultimately nukes the inode. This problem was originally reproduced by generic/388. Similar to how the insert range extent split code handles extent to btree conversion, update the collapse range extent merge code to handle btree to extent format conversion in the same transaction that merges the extents. This ensures that the inode fork format remains consistent if the filesystem happens to crash in the middle of a collapse range operation that changes the inode fork format. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> |
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| arch | ||
| block | ||
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| drivers | ||
| 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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| 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.
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.