35dc55b9e8
If xfs_bmapi_write finds a delalloc extent at the requested range, it tries to convert the entire delalloc extent to a real allocation. But if the allocator cannot find a single free extent large enough to cover the start block of the requested range, xfs_bmapi_write will return 0 but leave *nimaps set to 0. In that case we simply need to keep looping with the same startoffset_fsb so that one of the following allocations will eventually reach the requested range. Note that this could affect any caller of xfs_bmapi_write that covers an existing delayed allocation. As far as I can tell we do not have any other such caller, though - the regular writeback path uses xfs_bmapi_convert_delalloc to convert delayed allocations to real ones, and direct I/O invalidates the page cache first. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
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.