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Tony Krowiak 3b1eab7fb9 s390: vfio-ap: sysfs interfaces to configure control domains
Provides the sysfs interfaces for:

1. Assigning AP control domains to the mediated matrix device

2. Unassigning AP control domains from a mediated matrix device

3. Displaying the control domains assigned to a mediated matrix
   device

The IDs of the AP control domains assigned to the mediated matrix
device are stored in an AP domain mask (ADM). The bits in the ADM,
from most significant to least significant bit, correspond to
AP domain numbers 0 to 255. On some systems, the maximum allowable
domain number may be less than 255 - depending upon the host's
AP configuration - and assignment may be rejected if the input
domain ID exceeds the limit.

When a control domain is assigned, the bit corresponding its domain
ID will be set in the ADM. Likewise, when a domain is unassigned,
the bit corresponding to its domain ID will be cleared in the ADM.

The relevant sysfs structures are:

/sys/devices/vfio_ap/matrix/
...... [mdev_supported_types]
......... [vfio_ap-passthrough]
............ [devices]
...............[$uuid]
.................. assign_control_domain
.................. unassign_control_domain

To assign a control domain to the $uuid mediated matrix device's
ADM, write its domain number to the assign_control_domain file.
To unassign a domain, write its domain number to the
unassign_control_domain file. The domain number is specified
using conventional semantics: If it begins with 0x the number
will be parsed as a hexadecimal (case insensitive) number;
if it begins with 0, it is parsed as an octal number;
otherwise, it will be parsed as a decimal number.

For example, to assign control domain 173 (0xad) to the mediated
matrix device $uuid:

	echo 173 > assign_control_domain

	or

	echo 0255 > assign_control_domain

	or

	echo 0xad > assign_control_domain

To unassign control domain 173 (0xad):

	echo 173 > unassign_control_domain

	or

	echo 0255 > unassign_control_domain

	or

	echo 0xad > unassign_control_domain

The assignment will be rejected if the APQI exceeds the maximum
value for an AP domain:
  * If the AP Extended Addressing (APXA) facility is installed,
    the max value is 255
  * Else the max value is 15

Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Tested-by: Michael Mueller <mimu@linux.ibm.com>
Tested-by: Farhan Ali <alifm@linux.ibm.com>
Tested-by: Pierre Morel <pmorel@linux.ibm.com>
Message-Id: <20180925231641.4954-9-akrowiak@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-09-26 21:02:59 +02:00
arch s390: vfio-ap: base implementation of VFIO AP device driver 2018-09-26 20:45:51 +02:00
block blk-cgroup: increase number of supported policies 2018-09-11 10:59:53 -06:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto DMAengine updates for v4.19-rc1 2018-08-18 15:55:59 -07:00
Documentation Code of Conduct: Let's revamp it. 2018-09-16 11:42:28 -07:00
drivers s390: vfio-ap: sysfs interfaces to configure control domains 2018-09-26 21:02:59 +02:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs fixes for four CIFS/SMB3 potential pointer overflow issues, one minor build fix, and a build warning cleanup 2018-09-14 19:33:42 -10:00
include s390: vfio-ap: register matrix device with VFIO mdev framework 2018-09-26 20:45:51 +02:00
init Kbuild updates for v4.19 (2nd) 2018-08-25 13:40:38 -07:00
ipc ipc/shm: properly return EIDRM in shm_lock() 2018-09-04 16:45:02 -07:00
kernel Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-09-15 08:00:37 -10:00
lib lib/Kconfig.debug: fix three typos in help text 2018-09-04 16:45:02 -07:00
LICENSES LICENSES: Add Linux-OpenIB license text 2018-04-27 16:41:53 -06:00
mm overlayfs fixes for 4.19-rc4 2018-09-13 19:21:40 -10:00
net tipc: check return value of __tipc_dump_start() 2018-09-12 13:15:04 -07:00
samples samples/bpf: all XDP samples should unload xdp/bpf prog on SIGTERM 2018-08-16 21:55:32 +02:00
scripts Kbuild fixes for v4.19 2018-09-09 05:42:11 -07:00
security Revert "x86/mm/legacy: Populate the user page-table with user pgd's" 2018-09-14 17:08:45 +02:00
sound ALSA: hda: Fix several mismatch for register mask and value 2018-09-03 23:47:40 +02:00
tools Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-09-15 06:44:32 -10:00
usr initramfs: move gen_initramfs_list.sh from scripts/ to usr/ 2018-08-22 23:21:44 +09:00
virt KVM: Remove obsolete kvm_unmap_hva notifier backend 2018-09-07 15:06:02 +02:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Add hch to .get_maintainer.ignore 2015-08-21 14:30:10 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS s390: vfio-ap: register matrix device with VFIO mdev framework 2018-09-26 20:45:51 +02:00
Makefile Linux 4.19-rc4 2018-09-16 11:52:37 -07:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

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.
See Documentation/00-INDEX for a list of what is contained in each file.

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.