35a067b42d
Originally, we'd check for -ENOSPC when getting a disk reservation whenever the new extent took up more space on disk than the old extent. Erasure coding screwed this up, because with erasure coding writes are initially replicated, and then in the background the extra replicas are dropped when the stripe is created. This means that with erasure coding enabled, writes will always take up more space on disk than the data they're overwriting - but, according to posix, overwrites aren't supposed to return ENOSPC. So, in this patch we fudge things: if the new extent has more replicas than the _effective_ replicas of the old extent, or if the old extent is compressed and the new one isn't, we check for ENOSPC when getting the disk reservation - otherwise, we don't. Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
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.