b9dcfdff8b
Avoid the need to copy-paste the gup_test ioctl commands and the struct gup_test definition, between the kernel and the user space application, by providing a new header file for these. This allows easier and safer adding of new ioctl calls, as well as reducing the overall line count. Details: The header file has to be able to compile independently, because of the arguably unfortunate way that the Makefile is written: the Makefile tries to build all of its prerequisites, when really it should be only building the .c files, and leaving the other prerequisites (LOCAL_HDRS) as pure dependencies. That Makefile limitation is probably not worth fixing, but it explains why one of the includes had to be moved into the new header file. Also: simplify the ioctl struct (struct gup_test), by deleting the unused __expansion[10] field. This sort of thing is what you might see in a stable ABI, but this low-level, kernel-developer-oriented selftests/vm system is very much not subject to ABI stability. So "expansion" and "reserved" fields are unnecessary here. Link: https://lkml.kernel.org/r/20201026064021.3545418-3-jhubbard@nvidia.com Signed-off-by: John Hubbard <jhubbard@nvidia.com> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.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.