Ilya Dryomov
6484cbe987
With discard_zeroes_data gone in commit 48920ff2a5 ("block: remove
the discard_zeroes_data flag"), continuing to provide this guarantee is
pointless: applications can't query it and discards can only be used
for deallocating.
Add OBJ_OP_ZEROOUT and move the existing logic under it. As the first
step to divorcing OBJ_OP_DISCARD, stop worrying about copyups but keep
special casing whole-object layered discards.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jason Dillaman <dillaman@redhat.com>
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.