s390/ap: introduce mutex to lock the AP bus scan

Rework the invocations around ap_scan_bus():
- Protect ap_scan_bus() with a mutex to make sure only one
scan at a time is running.
- The workqueue invocation which is triggered by either the
module init or via AP bus scan timer expiration uses this
mutex and if there is already a scan running, the work
is simple aborted (as the job is done by another task).
- The ap_bus_force_rescan() which is invoked by higher level
layers mostly on failures which indicate a bus scan may
help is reworked to call ap_scan_bus() direct instead of
enqueuing work into a system workqueue and waiting for that
to finish. Of course the mutex is respected and in case of
another task already running a bus scan the shortcut of
waiting for this scan to finish and reusing the scan result
is taken.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/ap: rearm APQNs bindings complete completion

The APQN bindings complete completion was used to reflect
that 1st the AP bus initial scan is done and 2nd all the
detected APQNs have been bound to a device driver.
This was a single-shot action. However, as the AP bus
supports hot-plug it may be that new APQNs appear reflected
as new AP queue and card devices which need to be bound
to appropriate device drivers. So the condition that
all existing AP queue devices are bound to device drivers
may go away for a certain time.

This patch now checks during AP bus scan for maybe new AP
devices appearing and does a re-init of the internal completion
variable. So the AP bus function ap_wait_apqn_bindings_complete()
now may block on this condition variable even later after
initial scan is through when new APQNs appear which need to
get bound.

This patch also moves the check for binding complete invocation
from the probe function to the end of the AP bus scan function.
This change also covers some weird scenarios where during a
card hotplug the binding of the card device was sufficient for
binding complete but the queue devices where still in the
process of being discovered.

As of now this change has no impact on existing code. The
behavior change in the now later bindings complete should not
impact any code (and has been tested so far). The only
exploiter is the zcrypt function zcrypt_wait_api_operational()
which only initial calls ap_wait_apqn_bindings_complete().

However, this new behavior of the AP bus wait for APQNs bindings
complete function will be used in a later patch exploiting
this for the zcrypt API layer.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/ap: handle outband SE bind state change

This patch addresses some weird scenarios where an outband
manipulation of the SE bind state of a queue assigned and
maybe in use by an SE guest with AP pass-through support
took place. So for example when the guest has bound and
associated a queue and then this domain has been zeroed on
the service element.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

s390/ap: store TAPQ hwinfo in struct ap_card

As of now the AP card struct held only part of the
queue's hwinfo (that is the GR2 register content returned
with an TAPQ invocation). This patch reworks struct ap_card
to hold the whole hwinfo now.

As there is a nice bit field union on top of this
ap_tapq_hwinfo struct, all the ugly bit checkings can
now get replaced by simple evaluations of the required
bit field.

Suggested-by: Ingo Franzki <ifranzki@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

s390/ap: rework to use irq info from ap queue status

This patch reworks the irq handling and reporting code
for the AP queue interrupt handling to always use the
irq info from the queue status.

Until now the interrupt status of an AP queue was stored
into a bool variable within the ap_queue struct. This
variable was set on a successful interrupt enablement
and cleared with kicking a reset. However, it may be
that the interrupt state is manipulated outband for
example by a hypervisor. This patch removes this variable
and instead the irq bit from the AP queue status which is
always reflecting the current irq state is used.

Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/zcrypt: introduce new internal AP queue se_bound attribute

This patch introduces a new AP queue internal attribute
se_bound which reflects the bound state of an APQN within
a Secure Execution environment.

With introduction of Secure Execution guests now an
AP firmware queue needs to be bound to the guest before
usage. This patch introduces a new internal attribute
reflecting this bound state and some glue code to handle
this new field during lifetime of an AP queue device.

Together with that now the zcrypt scheduler considers
the state of the AP queues when a message is about to be
distributed among the existing queues. There is a new
function ap_queue_usable() which returns true only when
all conditions for using this AP queue device are fulfilled.
In details this means: the AP queue needs to be configured,
not checkstopped and within an SE environment it needs
to be bound. So the new function gives and indication
if the AP queue device is ready to serve requests or not.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/ap: re-init AP queues on config on

On a state toggle from config off to config on and on the
state toggle from checkstop to not checkstop the queue's
internal states was set but the state machine was not
nudged. This did not care as on the first enqueue of a
request the state machine kick ran.

However, within an Secure Execution guest a queue is
only chosen by the scheduler when it has been bound.
But to bind a queue, it needs to run through the initial
states (reset, enable interrupts, ...). So this is like
a chicken-and-egg problem and the result was in fact
that a queue was unusable after a config off/on toggle.

With some slight rework of the handling of these states
now the new function _ap_queue_init_state() is called
which is the core of the ap_queue_init_state() function
but without locking handling. This has the benefit that
it can be called on all the places where a (re-)init
of the AP queue's state machine is needed.

Fixes: 2d72eaf036d2 ("s390/ap: implement SE AP bind, unbind and associate")
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/zcrypt_ep11misc: support API ordinal 6 with empty pin-blob

Secure execution guest environments require an empty pinblob in all
key generation and unwrap requests. Empty pinblobs are only available
in EP11 API ordinal 6 or higher.

Add an empty pinblob to key generation and unwrap requests, if the AP
secure binding facility is available. In all other cases, stay with
the empty pin tag (no pinblob) and the current API ordinals.

The EP11 API ordinal also needs to be considered when the pkey module
tries to figure out the list of eligible cards for key operations
with protected keys in secure execution environment.

These changes are transparent to userspace but required for running
an secure execution guest with handling key generate and key derive
(e.g. secure key to protected key) correct. Especially using EP11
secure keys with the kernel dm-crypt layer requires this patch.

Co-developed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Holger Dengler <dengler@linux.ibm.com>
Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/zcrypt: remove CEX2 and CEX3 device drivers

Remove the legacy device driver code for CEX2 and CEX3 cards.

The last machines which are able to handle CEX2 crypto cards
are z10 EC first available 2008 and z10 BC first available 2009.
The last machines able to handle a CEX3 crypto card are
z196 first available 2010 and z114 first available 2011.

Please note that this does not imply to drop CEX2 and CEX3
support in general. With older kernels on hardware up to the
aforementioned machine models these crypto cards will get
support by IBM.

The removal of the CEX2 and CEX3 device drivers code opens up
some simplifications, for example support for crypto cards
without rng support can be removed also.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390: fix various typos

Fix various typos found with codespell.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

s390/zcrypt: cleanup some debug code

This patch removes most of the debug code which
is build in when CONFIG_ZCRYPT_DEBUG is enabled.
There is no real exploiter for this code any more and
at least one ioctl fails with this code enabled.

The CONFIG_ZCRYPT_DEBUG kernel config option still
makes sense as some debug sysfs entries can get
enabled with this and maybe long term a new better
designed debug and error injection way will get
introduced.

This patch only removes code surrounded by the named
kernel config option. This option should by default
always be off anyway. The structs and defines removed
by the patch have been used only by code surrounded
by a CONFIG_ZCRYPT_DEBUG ifdef and thus can be removed
also.

In the end this patch removes all the failure-injection
possibilities which had been available when the kernel
had been build with CONFIG_ZCRYPT_DEBUG. It has never
been used that much and was too unflexible anyway.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

s390/ap: implement SE AP bind, unbind and associate

Implementation of the new functions for SE AP support:
bind, unbind and associate. There are two new sysfs
attributes for this:

/sys/devices/ap/cardxx/xx.yyyy/se_bind
/sys/devices/ap/cardxx/xx.yyyy/se_associate

Writing a 1 into the se_bind attribute triggers the
SE AP bind for this AP queue, writing a 0 into does
an unbind - that's a reset (RAPQ) with the F bit enabled.

The se_associate attribute needs an integer value in
range 0...2^16-1 written in. This is the index into a
secrets table feed into the ultravisor. For more details
please see the Architecture documents.

These both new ap queue attributes are only visible
inside a SE guest with SB (Secure Binding) available.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/ap: introduce low frequency polling possibility

For some events the ap bus needs to poll. For example
when an AP queue is reset until the reset is through.
Also when no interrupt support is available (e.g. zVM)
there is a need to poll until all requests have been
processed and all replies have been delivered.

Polling is done with a high resolution timer by default
run with a rate of 4kHz (LPAR) or 666Hz (zVM guest).

For some events (wait for reset complete, wait for irq
enabled complete) this is a much too high poll rate
which triggers a lot of TAPQ invocations.

This patch introduces the possibility for the state
machine functions to return a new wait enum
AP_SM_WAIT_LOW_TIMEOUT which gives a hint to the
ap_wait() function to eventually set up the timer
with a more relaxed timeout value of 25Hz.

This patch also includes a slight rework of the sysfs
functions parsing the timer related stuff: Use of
kstrtobool and kstrtoul instead of sscanf.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/ap: filter ap card functions, new queue functions attribute

With SE SB (Secure Binding) some currently unused and thus always
zero bits in the TAPQ GR2 result are now used to show the binding
state of a queue. So to check if a card has changed the comparing
base is exactly this GR2 value shown as 'ap_function' in sysfs
(/sys/devices/ap/cardxx/ap_functions). Now there is some queue
specific info in this info and so a new mask TAPQ_CARD_FUNC_CMP_MASK
is used to filter out only the relevant bits for card compare.

For the same reason now the function bits (including exactly this
bind/associate information) need to be exposed to user space now.
So tools like lszcrypt can evaluate binding/association state on a
queue base. So here comes a new sysfs attribute

/sys/devices/ap/cardxx/xx.yyyy/ap_functions

This sysfs attribute is similar to the already existing
ap_functions attribute at ap card level. It shows the
upper 32 bits of GR2 from an invocation of TAPQ for this
AP queue.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/ap: exploit new B bit from QCI config info

This patch introduces an update to the ap_config_info
struct which is filled with the QCI subfunction. There
is a new bit apsb (short 'B') showing if the AP secure
bind facility is available. The patch also includes a
simple function ap_sb_available() wrapping this bit test.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/zcrypt: rework length information for dqap

The inline ap_dqap function does not return the number of
bytes actually written into the message buffer. The calling
code inspects the AP message header to figure out what kind
of AP message has been received and pulls the length
information from this header. This processing may not work
correctly in cases where only a fragment of the reply is
received.

With this patch the ap_dqap inline function now returns
the number of actually written bytes in the *length parameter.
So the calling function has a chance to compare the number of
received bytes against what the AP message header length
field states. This is especially useful in cases where a
message could only get partially received.

The low level reply processing functions needed some rework
to be able to catch this new length information and compare
it the right way. The rework also deals with some situations
where until now the reply length was not correctly calculated
and/or set.

All this has been heavily tested as the modifications on
the reply length information may affect crypto load.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/zcrypt: make psmid unsigned long instead of long long

Since s390 kernel build does not support 32 bit build any
more there is no difference between long and long long.
So this patch reworks all occurrences of psmid (a 64 bit
value) to use unsigned long now.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/ap: fix crash on older machines based on QCI info missing

On older z series machines (z12 and older) there is no QCI info
available. The AP code took care of this and the AP bus scan then
switched to simple probing via TAPQ.

With commit
283915850a44 ("s390/ap: notify drivers on config changed and scan complete callbacks")
some code was introduced which silently assumed that the QCI info is
always available. However, with KVM simulating an older machine (z12)
the result was a kernel crash. Funnily the same crash does not happen
on LPAR - maybe because NULL is a valid pointer and reading some data
from address 0 also works fine.

This fix now improves the code to be aware that the QCI instruction
may not be available on older machines and thus the two pointers to
QCI info structs may simple be NULL.

However, on a machine not providing the QCI info the two callbacks to
the zcrypt device drivers on_config_changed() and on_scan_complete()
provide parameters which are pointers to a QCI info struct.
These both callbacks are NOT served if there is no QCI info available.
The only consumer of these callbacks is the vfio device driver. This
driver only supports CEX4 and higher. All physical machines which are
able to provide CEX4 cards have QCI support available. So there is
no sense in for example fill the QCI info struct by hand with looping
over cards and queues and TAPQ each APQN.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Cc: stable@vger.kernel.org
Fixes: 283915850a44 ("s390/ap: notify drivers on config changed and scan complete callbacks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

s390/zcrypt: code cleanup

This patch tries to fix as much as possible of the
checkpatch.pl --strict findings:
CHECK: Logical continuations should be on the previous line
CHECK: No space is necessary after a cast
CHECK: Alignment should match open parenthesis
CHECK: 'useable' may be misspelled - perhaps 'usable'?
WARNING: Possible repeated word: 'is'
CHECK: spaces preferred around that '*' (ctx:VxV)
CHECK: Comparison to NULL could be written "!msg"
CHECK: Prefer kzalloc(sizeof(*zc)...) over kzalloc(sizeof(struct...)...)
CHECK: Unnecessary parentheses around resp_type->work
CHECK: Avoid CamelCase: <xcRB>

There is no functional change comming with this patch, only
code cleanup, renaming, whitespaces, indenting, ... but no
semantic change in any way. Also the API (zcrypt and pkey
header file) is semantically unchanged.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Jürgen Christ <jchrist@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/zcrypt: Add admask to zcdn

Zcrypt custom devices now support control domain masks. Users can set and
modify this mask to allow custom devices to access certain control domains.

Signed-off-by: Juergen Christ <jchrist@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/zcrypt: Support CPRB minor version T7

There is a new CPRB minor version T7 to be supported with
this patch. Together with this the functions which extract
the CPRB data from userspace and prepare the AP message do
now check the CPRB minor version and provide some info in
the flag field of the ap message struct for further processing.

The 3 functions doing this job have been renamed to
prep_cca_ap_msg, prep_ep11_ap_msg and prep_rng_ap_msg to
reflect their job better (old was get..fc).

This patch also introduces two new flags to be used internal
with the flag field of the struct ap_message:

AP_MSG_FLAG_USAGE is set when prep_cca_ap_msg or prep_ep11_ap_msg
come to the conclusion that this is a ordinary crypto load CPRB
(which means T2 for CCA CPRBs and no admin bit for EP11 CPRBs).

AP_MSG_FLAG_ADMIN is set when prep_cca_ap_msg or prep_ep11_ap_msg
think, this is an administrative (control) crypto load CPRB
(which means T3, T5, T6 or T7 for CCA CPRBs and admin bit set
for EP11 CPRBs).

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Jürgen Christ <jchrist@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/zcrypt: handle checkstopped cards with new state

A crypto card may be in checkstopped state. With this
patch this is handled as a new state in the ap card and
ap queue structs. There is also a new card sysfs attribute

/sys/devices/ap/cardxx/chkstop

and a new queue sysfs attribute

/sys/devices/ap/cardxx/xx.yyyy/chkstop

displaying the checkstop state of the card or queue. Please
note that the queue's checkstop state is only a copy of the
card's checkstop state but makes maintenance much easier.

The checkstop state expressed here is the result of an
RC 0x04 (CHECKSTOP) during an AP command, mostly the
PQAP(TAPQ) command which is 'testing' the queue.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Jürgen Christ <jchrist@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/zcrypt: CEX8S exploitation support

This patch adds CEX8 exploitation support for the AP bus code,
the zcrypt device driver zoo and the vfio device driver.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Jürgen Christ <jchrist@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/ap: notify drivers on config changed and scan complete callbacks

This patch introduces an extension to the ap bus to notify device drivers
when the host AP configuration changes - i.e., adapters, domains or
control domains are added or removed. When an adapter or domain is added to
the host's AP configuration, the AP bus will create the associated queue
devices in the linux sysfs device model. Each new type 10 (i.e., CEX4) or
newer queue device with an APQN that is not reserved for the default device
driver will get bound to the vfio_ap device driver. Likewise, whan an
adapter or domain is removed from the host's AP configuration, the AP bus
will remove the associated queue devices from the sysfs device model. Each
of the queues that is bound to the vfio_ap device driver will get unbound.

With the introduction of hot plug support, binding or unbinding of a
queue device will result in plugging or unplugging one or more queues from
a guest that is using the queue. If there are multiple changes to the
host's AP configuration, it could result in the probe and remove callbacks
getting invoked multiple times. Each time queues are plugged into or
unplugged from a guest, the guest's VCPUs must be taken out of SIE.
If this occurs multiple times due to changes in the host's AP
configuration, that can have an undesirable negative affect on the guest's
performance.

To alleviate this problem, this patch introduces two new callbacks: one to
notify the vfio_ap device driver when the AP bus scan routine detects a
change to the host's AP configuration; and, one to notify the driver when
the AP bus is done scanning. This will allow the vfio_ap driver to do
bulk processing of all affected adapters, domains and control domains for
affected guests rather than plugging or unplugging them one at a time when
the probe or remove callback is invoked. The two new callbacks are:

void (*on_config_changed)(struct ap_config_info *new_config_info,
struct ap_config_info *old_config_info);

This callback is invoked at the start of the AP bus scan
function when it determines that the host AP configuration information
has changed since the previous scan. This is done by storing
an old and current QCI info struct and comparing them. If there is any
difference, the callback is invoked.

void (*on_scan_complete)(struct ap_config_info *new_config_info,
struct ap_config_info *old_config_info);

The on_scan_complete callback is invoked after the ap bus scan is
completed if the host AP configuration data has changed.

Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/ap: driver callback to indicate resource in use

Introduces a new driver callback to prevent a root user from re-assigning
the APQN of a queue that is in use by a non-default host device driver to
a default host device driver and vice versa. The callback will be invoked
whenever a change to the AP bus's sysfs apmask or aqmask attributes would
result in one or more APQNs being re-assigned. If the callback responds
in the affirmative for any driver queried, the change to the apmask or
aqmask will be rejected with a device busy error.

For this patch, only non-default drivers will be queried. Currently,
there is only one non-default driver, the vfio_ap device driver. The
vfio_ap device driver facilitates pass-through of an AP queue to a
guest. The idea here is that a guest may be administered by a different
sysadmin than the host and we don't want AP resources to unexpectedly
disappear from a guest's AP configuration (i.e., adapters and domains
assigned to the matrix mdev). This will enforce the proper procedure for
removing AP resources intended for guest usage which is to
first unassign them from the matrix mdev, then unbind them from the
vfio_ap device driver.

Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/vfio-ap: add s390dbf logging to the vfio_ap_irq_enable function

This patch adds s390dbf logging to the function that executes the
PQAP(AQIC) instruction on behalf of the guest to which the queue for which
interrupts are being enabled or disabled is attached.

Currently, the vfio_ap_irq_enable function sets status response code 06
(notification indicator byte address (nib) invalid) in the status word
when the vfio_pin_pages function - called to pin the page containing the
nib - returns an error or a different number of pages pinned than
requested.

Setting the response code returned to userspace without also logging a
message in the kernel makes it impossible to determine whether the response
was due to an error detected by the vfio_ap device driver or because the
response code was returned by the firmware in response to the PQAP(AQIC)
instruction.

In addition to logging a warning for the situation above, this patch adds
the following:

* A function to validate the nib address invoked prior to calling the
vfio_pin_pages function. This allows for logging a message informing
the reader of the reason the page containing the nib can not be pinned
if the nib address is not valid. Response code 06 (invalid nib address)
will be set in the status word returned to the guest from the
instruction.

* Checks the return value from the kvm_s390_gisc_register and logs a
message informing the reader of the failure. Status response code 08
(invalid gisa) will be set in the status word returned to the guest from
the PQAP(AQIC) instruction.

* Checks the status response code returned from execution of the PQAP(AQIC)
instruction and if it indicates an error, logs a message informing the
reader.

Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/ap: fix state machine hang after failure to enable irq

If for any reason the interrupt enable for an ap queue fails the
state machine run for the queue returned wrong return codes to the
caller. So the caller assumed interrupt support for this queue in
enabled and thus did not re-establish the high resolution timer used
for polling. In the end this let to a hang for the user space process
waiting "forever" for the reply.

This patch reworks these return codes to return correct indications
for the caller to re-establish the timer when a queue runs without
interrupt support.

Please note that this is fixing a wrong behavior after a first
failure (enable interrupt support for the queue) failed. However,
looks like this occasionally happens on KVM systems.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/ap: use the common driver-data pointer

The device struct provides a pointer for driver-private data. Use this
in the zcrypt drivers (as vfio_ap already does), and then remove the
custom pointer from the AP device structs.

As really_probe() will always clear the drvdata pointer on error, we
no longer have to do so ourselves.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/ap: use the common device_driver pointer

The device struct itself already contains a pointer to its driver.
Use this consistently, instead of duplicating it.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/AP: support new dynamic AP bus size limit

This patch provides support for new dynamic AP bus message limit
with the existing zcrypt device driver and AP bus core code.

There is support for a new field 'ml' from TAPQ query. The field
gives if != 0 the AP bus limit for this card in 4k chunk units.
The actual message size limit per card is shown as a new read-only
sysfs attribute. The sysfs attribute

/sys/devices/ap/cardxx/max_msg_size

shows the upper limit in bytes used by the AP bus and zcrypt device
driver for requests and replies send to and received from this card.
Currently up to CEX7 support only max 12kB msg size and thus the field
shows 12288 meaning the upper limit of a valid msg for this card is
12kB. Please note that the usable payload is somewhat lower and
depends on the msg type and thus the header struct which is to be
prepended by the zcrypt dd.

The dispatcher responsible for choosing the right card and queue is
aware of the individual card AP bus message limit. So a request is
only assigned to a queue of a card which is able to handle the size of
the request (e.g. a 14kB request will never go to a max 12kB card).
If no such card is found the ioctl will fail with ENODEV.

The reply buffer held by the device driver is determined by the ml
field of the TAPQ for this card. If a response from the card exceeds
this limit however, the response is not truncated but the ioctl for
this request will fail with errno EMSGSIZE to indicate that the device
driver has dropped the response because it would overflow the buffer
limit.

If the request size does not indicate to the dispatcher that an
adapter with extended limit is to be used, a random card will be
chosen when no specific card is addressed (ANY addressing). This may
result in an ioctl failure when the reply size needs an adapter with
extended limit but the randomly chosen one is not capable of handling
the broader reply size. The user space application needs to use
dedicated addressing to forward such a request only to suitable cards
to get requests like this processed properly.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Ingo Tuchscherer <ingo.tuchscherer@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/ap/zcrypt: notify userspace with online, config and mode info

This patch brings 3 reworked/new uevent changes:
* All AP uevents caused by an ap card or queue device now carry an
additional uevent env value MODE=<accel|cca|ep11>. Here is an
example:
KERNEL[1267.301292] add /devices/ap/card0a (ap)
ACTION=add
DEVPATH=/devices/ap/card0a
SUBSYSTEM=ap
DEVTYPE=ap_card
DEV_TYPE=000D
MODALIAS=ap:t0D
MODE=ep11 <- this is new
SEQNUM=1095
This is true for bind, unbind, add, remove, and change uevents
related to ap card or ap queue devices.
* On a change of the soft online attribute on a zcrypt queue or card
device a new CHANGE uevent is sent with an env value ONLINE=<0|1>.
Example uevent:
KERNEL[613.067531] change /devices/ap/card09/09.0011 (ap)
ACTION=change
DEVPATH=/devices/ap/card09/09.0011
SUBSYSTEM=ap
ONLINE=0 <- this is new
DEVTYPE=ap_queue
DRIVER=cex4queue
MODE=cca
SEQNUM=1070
- On a change of the config state of an zcrypt card device a new
CHANGE uevent is sent with an env value CONFIG=<0|1>.
Example uevent:
KERNEL[876.258680] change /devices/ap/card09 (ap)
ACTION=change
DEVPATH=/devices/ap/card09
SUBSYSTEM=ap
CONFIG=0 <- this is new
DEVTYPE=ap_card
DRIVER=cex4card
DEV_TYPE=000D
MODALIAS=ap:t0D
MODE=cca
SEQNUM=1073
Setting a card config on/off causes the dependent queue devices to
follow the config state change and thus uevents informing about the
config state change for the queue devices are also emitted.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/ap: ap bus userspace notifications for some bus conditions

This patch adds notifications to userspace for two important
conditions of the ap bus:

I) Initial ap bus scan done. This indicates that the initial
scan of all the ap devices (cards, queues) is complete and
ap devices have been build up for all the hardware found.
This condition is signaled with
1) An ap bus change uevent send to userspace with an environment
key/value pair "INITSCAN=done":
# udevadm monitor -k -p
...
KERNEL[97.830919] change /devices/ap (ap)
ACTION=change
DEVPATH=/devices/ap
SUBSYSTEM=ap
INITSCAN=done
SEQNUM=10421
2) A sysfs attribute /sys/bus/ap/scans which shows the
number of completed ap bus scans done since bus init.
So a value of 1 or greater signals that the initial
ap bus scan is complete.
Note: The initial ap bus scan complete condition is fulfilled
and will be signaled even if there was no ap resource found.

II) APQN driver bindings complete. This indicates that all
APQNs have been bound to an zcrypt or alternate device
driver. Only with the help of an device driver an APQN
can be used for crypto load. So the binding complete
condition is the starting point for user space to be
sure all crypto resources on the ap bus are available
for use.
This condition is signaled with
1) An ap bus change uevent send to userspace with an environment
key/value pair "BINDINGS=complete":
# udevadm monitor -k -p
...
KERNEL[97.830975] change /devices/ap (ap)
ACTION=change
DEVPATH=/devices/ap
SUBSYSTEM=ap
BINDINGS=complete
SEQNUM=10422
2) A sysfs attribute /sys/bus/ap/bindings showing
"<nr of bound apqns>/<total nr of apqns> (complete)"
when all available apqns have been bound to device drivers, or
"<nr of bound apqns>/<total nr of apqns>"
when there are some apqns not bound to an device driver.
Note: The binding complete condition is also fulfilled, when
there are no apqns available to bind any device driver. In
this case the binding complete will be signaled AFTER init
scan is done.
Note: This condition may arise multiple times when after
initial scan modifications on the bindings take place. For
example a manual unbind of an APQN switches the binding
complete condition off. When at a later time the unbound APQNs
are bound with an device driver the binding is (again) complete
resulting in another uevent and marking the bindings sysfs
attribute with '(complete)'.

There is also a new function to be used within the kernel:

int ap_wait_init_apqn_bindings_complete(unsigned long timeout)

Interface to wait for the AP bus to have done one initial ap bus
scan and all detected APQNs have been bound to device drivers.
If these both conditions are not fulfilled, this function blocks
on a condition with wait_for_completion_interruptible_timeout().
If these both conditions are fulfilled (before the timeout hits)
the return value is 0. If the timeout (in jiffies) hits instead
-ETIME is returned. On failures negative return values are
returned to the caller. Please note that further unbind/bind
actions after initial binding complete is through do not cause this
function to block again.

Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/zcrypt: Introduce Failure Injection feature

Introduce a way to specify additional debug flags with an crpyto
request to be able to trigger certain failures within the zcrypt
device drivers and/or ap core code.

This failure injection possibility is only enabled with a kernel debug
build CONFIG_ZCRYPT_DEBUG) and should never be available on a regular
kernel running in production environment.

Details:

* The ioctl(ICARSAMODEXPO) get's a struct ica_rsa_modexpo. If the
leftmost bit of the 32 bit unsigned int inputdatalength field is
set, the uppermost 16 bits are separated and used as debug flag
value. The process is checked to have the CAP_SYS_ADMIN capability
enabled or EPERM is returned.

* The ioctl(ICARSACRT) get's a struct ica_rsa_modexpo_crt. If the
leftmost bit of the 32 bit unsigned int inputdatalength field is set,
the uppermost 16 bits are separated and used als debug flag
value. The process is checked to have the CAP_SYS_ADMIN capability
enabled or EPERM is returned.

* The ioctl(ZSECSENDCPRB) used to send CCA CPRBs get's a struct
ica_xcRB. If the leftmost bit of the 32 bit unsigned int status
field is set, the uppermost 16 bits of this field are used as debug
flag value. The process is checked to have the CAP_SYS_ADMIN
capability enabled or EPERM is returned.

* The ioctl(ZSENDEP11CPRB) used to send EP11 CPRBs get's a struct
ep11_urb. If the leftmost bit of the 64 bit unsigned int req_len
field is set, the uppermost 16 bits of this field are used as debug
flag value. The process is checked to have the CAP_SYS_ADMIN
capability enabled or EPERM is returned.

So it is possible to send an additional 16 bit value to the zcrypt API
to be used to carry a failure injection command which may trigger
special behavior within the zcrypt API and layers below. This 16 bit
value is for the rest of the test referred as 'fi command' for Failure
Injection.

The lower 8 bits of the fi command construct a numerical argument in
the range of 1-255 and is the 'fi action' to be performed with the
request or the resulting reply:

* 0x00 (all requests): No failure injection action but flags may be
provided which may affect the processing of the request or reply.
* 0x01 (only CCA CPRBs): The CPRB's agent_ID field is set to
'FF'. This results in an reply code 0x90 (Transport-Protocol
Failure).
* 0x02 (only CCA CPRBs): After the APQN to send to has been chosen,
the domain field within the CPRB is overwritten with value 99 to
enforce an reply with RY 0x8A.
* 0x03 (all requests): At NQAP invocation the invalid qid value 0xFF00
is used causing an response code of 0x01 (AP queue not valid).

The upper 8 bits of the fi command may carry bit flags which may
influence the processing of an request or response:

* 0x01: No retry. If this bit is set, the usual loop in the zcrypt API
which retries an CPRB up to 10 times when the lower layers return
with EAGAIN is abandoned after the first attempt to send the CPRB.
* 0x02: Toggle special. Toggles the special bit on this request. This
should result in an reply code RY~0x41 and result in an ioctl
failure with errno EINVAL.

This failure injection possibilities may get some further extensions
in the future. As of now this is a starting point for Continuous Test
and Integration to trigger some failures and watch for the reaction of
the ap bus and zcrypt device driver code.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/ap/zcrypt: revisit ap and zcrypt error handling

Revisit the ap queue error handling: Based on discussions and
evaluatios with the firmware folk here is now a rework of the response
code handling for all the AP instructions. The idea is to distinguish
between failures because of some kind of invalid request where a retry
does not make any sense and a failure where another attempt to send
the very same request may succeed. The first case is handled by
returning EINVAL to the userspace application. The second case results
in retries within the zcrypt API controlled by a per message retry
counter.

Revisit the zcrpyt error handling: Similar here, based on discussions
with the firmware people here comes a rework of the handling of all
the reply codes. Main point here is that there are only very few
cases left, where a zcrypt device queue is switched to offline. It
should never be the case that an AP reply message is 'unknown' to the
device driver as it indicates a total mismatch between device driver
and crypto card firmware. In all other cases, the code distinguishes
between failure because of invalid message (see above - EINVAL) or
failures of the infrastructure (see above - EAGAIN).

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/ap: add card/queue deconfig state

This patch adds a new config state to the ap card and queue
devices. This state reflects the response code
0x03 "AP deconfigured" on TQAP invocation and is tracked with
every ap bus scan.

Together with this new state now a card/queue device which
is 'deconfigured' is not disposed any more. However, for backward
compatibility the online state now needs to take this state into
account. So a card/queue is offline when the device is not configured.
Furthermore a device can't get switched from offline to online state
when not configured.

The config state is shown in sysfs at
/sys/devices/ap/cardxx/config
for the card and
/sys/devices/ap/cardxx/xx.yyyy/config
for each queue within each card.
It is a read-only attribute reflecting the negation of the
'AP deconfig' state as it is noted in the AP documents.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/ap: add error response code field for ap queue devices

On AP instruction failures the last response code is now
kept in the struct ap_queue. There is also a new sysfs
attribute showing this field (enabled only on debug kernels).

Also slight rework of the AP_DBF macros to get some more
content into one debug feature message line.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/ap: split ap queue state machine state from device state

The state machine for each ap queue covered a mixture of
device states and state machine (firmware queue state) states.

This patch splits the device states and the state machine
states into two different enums and variables. The major
state is the device state with currently these values:

AP_DEV_STATE_UNINITIATED - fresh and virgin, not touched
AP_DEV_STATE_OPERATING - queue dev is working normal
AP_DEV_STATE_SHUTDOWN - remove/unbind/shutdown in progress
AP_DEV_STATE_ERROR - device is in error state

only when the device state is > UNINITIATED the state machine
is run. The state machine represents the states of the firmware
queue:

AP_SM_STATE_RESET_START - starting point, reset (RAPQ) ap queue
AP_SM_STATE_RESET_WAIT - reset triggered, waiting to be finished
if irqs enabled, set up irq (AQIC)
AP_SM_STATE_SETIRQ_WAIT - enable irq triggered, waiting to be
finished, then go to IDLE
AP_SM_STATE_IDLE - queue is operational but empty
AP_SM_STATE_WORKING - queue is operational, requests are stored
and replies may wait for getting fetched
AP_SM_STATE_QUEUE_FULL - firmware queue is full, so only replies
can get fetched

For debugging each ap queue shows a sysfs attribute 'states' which
displays the device and state machine state and is only available
when the kernel is build with CONFIG_ZCRYPT_DEBUG enabled.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

mm, treewide: rename kzfree() to kfree_sensitive()

As said by Linus:

A symmetric naming is only helpful if it implies symmetries in use.
Otherwise it's actively misleading.

In "kzalloc()", the z is meaningful and an important part of what the
caller wants.

In "kzfree()", the z is actively detrimental, because maybe in the
future we really _might_ want to use that "memfill(0xdeadbeef)" or
something. The "zero" part of the interface isn't even _relevant_.

The main reason that kzfree() exists is to clear sensitive information
that should not be leaked to other future users of the same memory
objects.

Rename kzfree() to kfree_sensitive() to follow the example of the recently
added kvfree_sensitive() and make the intention of the API more explicit.
In addition, memzero_explicit() is used to clear the memory to make sure
that it won't get optimized away by the compiler.

The renaming is done by using the command sequence:

git grep -w --name-only kzfree |\
xargs sed -i 's/kzfree/kfree_sensitive/'

followed by some editing of the kfree_sensitive() kerneldoc and adding
a kzfree backward compatibility macro in slab.h.

[akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h]
[akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more]

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Joe Perches <joe@perches.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Jason A . Donenfeld" <Jason@zx2c4.com>
Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

s390/ap: rename and clarify ap state machine related stuff

There is a state machine held for each ap queue device.
The states and functions related to this where somethimes
noted with _sm_ somethimes without. This patch clarifies
and renames all the ap queue state machine related functions,
enums and defines to have a _sm_ in the name.

There is no functional change coming with this patch - it's
only beautifying code.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

s390/zcrypt: code beautification and struct field renames

Some beautifications related to the internal only used
struct ap_message and related code. Instead of one int carrying
only the special flag now a u32 flags field is used.

At struct CPRBX the pointers to additional data are now marked
with __user. This caused some changes needed on code, where
these structs are also used within the zcrypt misc functions.

The ica_rsa_* structs now use the generic types __u8, __u32, ...
instead of char, unsigned int.

zcrypt_msg6 and zcrypt_msg50 use min_t() instead of min().

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

s390/ap: introduce new ap function ap_get_qdev()

Provide a new interface function to be used by the ap drivers:
struct ap_queue *ap_get_qdev(ap_qid_t qid);
Returns ptr to the struct ap_queue device or NULL if there
was no ap_queue device with this qid found. When something is
found, the reference count of the embedded device is increased.
So the caller has to decrease the reference count after use
with a call to put_device(&aq->ap_dev.device).

With this patch also the ap_card_list is removed from the
ap core code and a new hashtable is introduced which stores
hnodes of all the ap queues known to the ap bus.

The hashtable approach and a first implementation of this
interface comes from a previous patch from
Anthony Krowiak and an idea from Halil Pasic.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Suggested-by: Tony Krowiak <akrowiak@linux.ibm.com>
Suggested-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/ap: remove power management code from ap bus and drivers

The s390 power management support has been removed. So the
api registration and the suspend and resume callbacks and
all the code related to this for the ap bus and the ap drivers
is removed with this patch.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/zcrypt: fix card and queue total counter wrap

The internal statistic counters for the total number of
requests processed per card and per queue used integers. So they do
wrap after a rather huge amount of crypto requests processed. This
patch introduces uint64 counters which should hold much longer but
still may wrap. The sysfs attributes request_count for card and queue
also used only %ld and now display the counter value with %llu.

This is not a security relevant fix. The int overflow which happened
is not in any way exploitable as a security breach.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/zcrypt: move ap device reset from bus to driver code

This patch moves the reset invocation of an ap device when
fresh detected from the ap bus to the probe() function of
the driver responsible for this device.

The virtualisation of ap devices makes it necessary to
remove unconditioned resets on fresh appearing apqn devices.
It may be that such a device is already enabled for guest
usage. So there may be a race condition between host ap bus
and guest ap bus doing the reset. This patch moves the
reset from the ap bus to the zcrypt drivers. So if there
is no zcrypt driver bound to an ap device - for example
the ap device is bound to the vfio device driver - the
ap device is untouched passed to the vfio device driver.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/zcrypt: CEX7S exploitation support

This patch adds CEX7 exploitation support for the AP bus code,
the zcrypt device driver zoo and the vfio device driver.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/zcrypt: Fix wrong dispatching for control domain CPRBs

The zcrypt device driver does not handle CPRBs which address
a control domain correctly. This fix introduces a workaround:
The domain field of the request CPRB is checked if there is
a valid domain value in there. If this is true and the value
is a control only domain (a domain which is enabled in the
crypto config ADM mask but disabled in the AQM mask) the
CPRB is forwarded to the default usage domain. If there is
no default domain, the request is rejected with an ENODEV.

This fix is important for maintaining crypto adapters. For
example one LPAR can use a crypto adapter domain ('Control
and Usage') but another LPAR needs to be able to maintain
this adapter domain ('Control'). Scenarios like this did
not work properly and the patch enables this.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

s390/zcrypt: revisit ap device remove procedure

Working with the vfio-ap driver let to some revisit of the way
how an ap (queue) device is removed from the driver.
With the current implementation all the cleanup was done before
the driver even got notified about the removal. Now the ap
queue removal is done in 3 steps:
1) A preparation step, all ap messages within the queue
are flushed and so the driver does 'receive' them.
Also a new state AP_STATE_REMOVE assigned to the queue
makes sure there are no new messages queued in.
2) Now the driver's remove function is invoked and the
driver should do the job of cleaning up it's internal
administration lists or whatever. After 2) is done
it is guaranteed, that the driver is not invoked any
more. On the other hand the driver has to make sure
that the APQN is not accessed any more after step 2
is complete.
3) Now the ap bus code does the job of total cleanup of the
APQN. A reset with zero is triggered and the state of
the queue goes to AP_STATE_UNBOUND.
After step 3) is complete, the ap queue has no pending
messages and the APQN is cleared and so there are no
requests and replies lingering around in the firmware
queue for this APQN. Also the interrupts are disabled.

After these remove steps the ap queue device may be assigned
to another driver.

Stress testing this remove/probe procedure showed a problem with the
correct module reference counting. The actual receive of an reply in
the driver is done asynchronous with completions. So with a driver
change on an ap queue the message flush triggers completions but the
threads waiting for the completions may run at a time where the queue
already has the new driver assigned. So the module_put() at receive
time needs to be done on the driver module which queued the ap
message. This change is also part of this patch.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: use new state UNBOUND during queue driver rebind

When an alternate driver (vfio-ap) has bound an ap queue and this
binding is revised the ap queue device is in an intermittent
state not bound to any driver. The internal state variable
covered this with the state AP_STATE_BORKED which is also used to
reflect broken devices. When now an ap bus scan runs such a
device is destroyed and on the next scan reconstructed.

So a stress test with high frequency switching the queue driver
between the default and the vfio-ap driver hit this gap and the
queue was removed until the next ap bus scan. This fix now
introduces another state for the in-between condition for a queue
momentary not bound to a driver and so the ap bus scan function
skips this device instead of removing it.

Also some very slight but maybe helpful debug feature messages
come with this patch - in particular a message showing that a
broken card/queue device will get removed.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: reinit ap queue state machine during device probe

Until the vfio-ap driver came into live there was a well known
agreement about the way how ap devices are initialized and their
states when the driver's probe function is called.

However, the vfio device driver when receiving an ap queue device does
additional resets thereby removing the registration for interrupts for
the ap device done by the ap bus core code. So when later the vfio
driver releases the device and one of the default zcrypt drivers takes
care of the device the interrupt registration needs to get
renewed. The current code does no renew and result is that requests
send into such a queue will never see a reply processed - the
application hangs.

This patch adds a function which resets the aq queue state machine for
the ap queue device and triggers the walk through the initial states
(which are reset and registration for interrupts). This function is
now called before the driver's probe function is invoked.

When the association between driver and device is released, the
driver's remove function is called. The current implementation calls a
ap queue function ap_queue_remove(). This invokation has been moved to
the ap bus function to make the probe / remove pair for ap bus and
drivers more symmetric.

Fixes: 7e0bdbe5c21c ("s390/zcrypt: AP bus support for alternate driver(s)")
Cc: stable@vger.kernel.org # 4.19+
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewd-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewd-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: multiple zcrypt device nodes support

This patch is an extension to the zcrypt device driver to provide,
support and maintain multiple zcrypt device nodes. The individual
zcrypt device nodes can be restricted in terms of crypto cards,
domains and available ioctls. Such a device node can be used as a
base for container solutions like docker to control and restrict
the access to crypto resources.

The handling is done with a new sysfs subdir /sys/class/zcrypt.
Echoing a name (or an empty sting) into the attribute "create" creates
a new zcrypt device node. In /sys/class/zcrypt a new link will appear
which points to the sysfs device tree of this new device. The
attribute files "ioctlmask", "apmask" and "aqmask" in this directory
are used to customize this new zcrypt device node instance. Finally
the zcrypt device node can be destroyed by echoing the name into
/sys/class/zcrypt/destroy. The internal structs holding the device
info are reference counted - so a destroy will not hard remove a
device but only marks it as removable when the reference counter drops
to zero.

The mask values are bitmaps in big endian order starting with bit 0.
So adapter number 0 is the leftmost bit, mask is 0x8000... The sysfs
attributes accept 2 different formats:
* Absolute hex string starting with 0x like "0x12345678" does set
the mask starting from left to right. If the given string is shorter
than the mask it is padded with 0s on the right. If the string is
longer than the mask an error comes back (EINVAL).
* Relative format - a concatenation (done with ',') of the
terms +<bitnr>[-<bitnr>] or -<bitnr>[-<bitnr>]. <bitnr> may be any
valid number (hex, decimal or octal) in the range 0...255. Here are
some examples:
"+0-15,+32,-128,-0xFF"
"-0-255,+1-16,+0x128"
"+1,+2,+3,+4,-5,-7-10"

A simple usage examples:

# create new zcrypt device 'my_zcrypt':
echo "my_zcrypt" >/sys/class/zcrypt/create
# go into the device dir of this new device
echo "my_zcrypt" >create
cd my_zcrypt/
ls -l
total 0
-rw-r--r-- 1 root root 4096 Jul 20 15:23 apmask
-rw-r--r-- 1 root root 4096 Jul 20 15:23 aqmask
-r--r--r-- 1 root root 4096 Jul 20 15:23 dev
-rw-r--r-- 1 root root 4096 Jul 20 15:23 ioctlmask
lrwxrwxrwx 1 root root 0 Jul 20 15:23 subsystem -> ../../../../class/zcrypt
...
# customize this zcrypt node clone
# enable only adapter 0 and 2
echo "0xa0" >apmask
# enable only domain 6
echo "+6" >aqmask
# enable all 256 ioctls
echo "+0-255" >ioctls
# now the /dev/my_zcrypt may be used
# finally destroy it
echo "my_zcrypt" >/sys/class/zcrypt/destroy

Please note that a very similar 'filtering behavior' also applies to
the parent z90crypt device. The two mask attributes apmask and aqmask
in /sys/bus/ap act the very same for the z90crypt device node. However
the implementation here is totally different as the ap bus acts on
bind/unbind of queue devices and associated drivers but the effect is
still the same. So there are two filters active for each additional
zcrypt device node: The adapter/domain needs to be enabled on the ap
bus level and it needs to be active on the zcrypt device node level.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: AP bus support for alternate driver(s)

The current AP bus, AP devices and AP device drivers implementation
uses a clearly defined mapping for binding AP devices to AP device
drivers. So for example a CEX6C queue will always be bound to the
cex4queue device driver.

The Linux Device Driver model has no sensitivity for more than one
device driver eligible for one device type. If there exist more than
one drivers matching to the device type, simple all drivers are tried
consecutively. There is no way to determine and influence the probing
order of the drivers.

With KVM there is a need to provide additional device drivers matching
to the very same type of AP devices. With a simple implementation the
KVM drivers run in competition to the regular drivers. Whichever
'wins' a device depends on build order and implementation details
within the common Linux Device Driver Model and is not
deterministic. However, a userspace process could figure out which
device should be bound to which driver and sort out the correct
binding by manipulating attributes in the sysfs.

If for security reasons a AP device must not get bound to the 'wrong'
device driver the sorting out has to be done within the Linux kernel
by the AP bus code. This patch modifies the behavior of the AP bus
for probing drivers for devices in a way that two sets of drivers are
usable. Two new bitmasks 'apmask' and 'aqmask' are used to mark a
subset of the APQN range for 'usable by the ap bus and the default
drivers' or 'not usable by the default drivers and thus available for
alternate drivers like vfio-xxx'. So an APQN which is addressed by
this masking only the default drivers will be probed. In contrary an
APQN which is not addressed by the masks will never be probed and
bound to default drivers but onny to alternate drivers.

Eventually the two masks give a way to divide the range of APQNs into
two pools: one pool of APQNs used by the AP bus and the default
drivers and thus via zcrypt drivers available to the userspace of the
system. And another pool where no zcrypt drivers are bound to and
which can be used by alternate drivers (like vfio-xxx) for their
needs. This division is hot-plug save and makes sure a APQN assigned
to an alternate driver is at no time somehow exploitable by the wrong
party.

The two masks are located in sysfs at /sys/bus/ap/apmask and
/sys/bus/ap/aqmask. The mask syntax is exactly the same as the
already existing mask attributes in the /sys/bus/ap directory (for
example ap_usage_domain_mask and ap_control_domain_mask).

By default all APQNs belong to the ap bus and the default drivers:

cat /sys/bus/ap/apmask
0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
cat /sys/bus/ap/aqmask
0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff

The masks can be changed at boot time with the kernel command line
like this:

... ap.apmask=0xffff ap.aqmask=0x40

This would give these two pools:

default drivers pool: adapter 0 - 15, domain 1
alternate drivers pool: adapter 0 - 15, all but domain 1
adapter 16-255, all domains

The sysfs attributes for this two masks are writeable and an
administrator is able to reconfigure the assignements on the fly by
writing new mask values into. With changing the mask(s) a revision of
the existing queue to driver bindings is done. So all APQNs which are
bound to the 'wrong' driver are reprobed via kernel function
device_reprobe() and thus the new correct driver will be assigned with
respect of the changed apmask and aqmask bits.

The mask values are bitmaps in big endian order starting with bit 0.
So adapter number 0 is the leftmost bit, mask is 0x8000... The sysfs
attributes accept 2 different formats:
- Absolute hex string starting with 0x like "0x12345678" does set
the mask starting from left to right. If the given string is shorter
than the mask it is padded with 0s on the right. If the string is
longer than the mask an error comes back (EINVAL).
- '+' or '-' followed by a numerical value. Valid examples are "+1",
"-13", "+0x41", "-0xff" and even "+0" and "-0". Only the addressed
bit in the mask is switched on ('+') or off ('-').

This patch will also be the base for an upcoming extension to the
zcrypt drivers to be able to provide additional zcrypt device nodes
with filtering based on ap and aq masks.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: code beautify

Code beautify by following most of the checkpatch suggestions:
- SPDX license identifier line complains by checkpatch
- missing space or newline complains by checkpatch
- octal numbers for permssions complains by checkpatch
- renaming of static sysfs functions complains by checkpatch
- fix of block comment complains by checkpatch
- fix printf like calls where function name instead of %s __func__
was used
- __packed instead of __attribute__((packed))
- init to zero for static variables removed
- use of DEVICE_ATTR_RO and DEVICE_ATTR_RW macros

No functional code changes or API changes!

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: Integrate ap_asm.h into include/asm/ap.h.

Move all the inline functions from the ap bus header
file ap_asm.h into the in-kernel api header file
arch/s390/include/asm/ap.h so that KVM can make use
of all the low level AP functions.

Signed-off-by: Harald Freudenberger <freude@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: Fix CCA and EP11 CPRB processing failure memory leak.

Tests showed, that the zcrypt device driver produces memory
leaks when a valid CCA or EP11 CPRB can't get delivered or has
a failure during processing within the zcrypt device driver.

This happens when a invalid domain or adapter number is used
or the lower level software or hardware layers produce any
kind of failure during processing of the request.

Only CPRBs send to CCA or EP11 cards can produce this memory
leak. The accelerator and the CPRBs processed by this type
of crypto card is not affected.

The two fields message and private within the ap_message struct
are allocated with pulling the function code for the CPRB but
only freed when processing of the CPRB succeeds. So for example
an invalid domain or adapter field causes the processing to
fail, leaving these two memory areas allocated forever.

Signed-off-by: Harald Freudenberger <freude@de.ibm.com>
Reviewed-by: Ingo Franzki <ifranzki@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: Support up to 256 crypto adapters.

There was an artificial restriction on the card/adapter id
to only 6 bits but all the AP commands do support adapter
ids with 8 bit. This patch removes this restriction to 64
adapters and now up to 256 adapter can get addressed.

Some of the ioctl calls work on the max number of cards
possible (which was 64). These ioctls are now deprecated
but still supported. All the defines, structs and ioctl
interface declarations have been kept for compabibility.
There are now new ioctls (and defines for these) with an
additional '2' appended which provide the extended versions
with 256 cards supported.

Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: remove unused functions and declarations

The AP bus code is not available as kernel module any more.
There was some leftover code dealing with kernel module
exit which has been removed with this patch.

Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390: crypto: Remove redundant license text

Now that the SPDX tag is in all drivers/s390/crypto/ files, that
identifies the license in a specific and legally-defined manner. So the
extra GPL text wording can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text. And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Cc: Harald Freudenberger <freude@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390: crypto: add SPDX identifiers to the remaining files

It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/s390/crypto/ files with the correct SPDX license
identifier based on the license text in the file itself. The SPDX
identifier is a legally binding shorthand, which can be used instead of
the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Harald Freudenberger <freude@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/ap_bus: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: Harald Freudenberger <freude@de.ibm.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

s390/zcrypt: Introduce QACT support for AP bus devices.

This patch introduces a new ap_qact() function which
exploits the PQAP(QACT) subfunction. QACT is a new
interface to Query the Ap Compatilibity Type based
on a given AP qid, type, mode and version.

Based on this new function the AP bus scan code is
slightly reworked to use this new interface for
querying the compatible type for each new AP queue
device detected. So new and unknown devices can
get automatically mapped to a compatible type and
handled without the need for toleration patches
for every new hardware.

The currently highest known hardware is CEX6S.
With this patch a possible successor can get
queried for a combatible type known by the device
driver without the need for an toleration patch.

Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: externalize AP config info query

KVM has a need to fetch the crypto configuration information
as it is returned by the PQAP(QCI) instruction. This patch
introduces a new API ap_query_configuration() which provides
this info in a handy way for the caller.

Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: externalize test AP queue

Under certain specified conditions, the Test AP Queue (TAPQ)
subfunction of the Process Adjunct Processor Queue (PQAP) instruction
will be intercepted by a guest VM. The guest VM must have a means for
executing the intercepted instruction.

The vfio_ap driver will provide an interface to execute the
PQAP(TAPQ) instruction subfunction on behalf of a guest VM.
The code for executing the AP instructions currently resides in the
AP bus. This patch refactors the AP bus code to externalize access
to the PQAP(TAPQ) instruction subfunction to make it available to
the vfio_ap driver.

Signed-off-by: Tony Krowiak <akrowiak@linux.vnet.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: Fixed attrition of AP adapters and domains

Currently the first eligible AP adapter respectively domain will be
selected to service requests. In case of sequential workload, the
very same adapter/domain will be used.

The adapter/domain selection algorithm now considers the completed
transactions per adaper/domain and therefore ensures a homogeneous
utilization.

Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: add multi domain support

Currently the ap infrastructure only supports one domain at a time.
This feature extends the generic cryptographic device driver to
support multiple cryptographic domains simultaneously.

There are now card and queue devices on the AP bus with independent
card and queue drivers. The new /sys layout is as follows:

/sys/bus/ap
devices
<xx>.<yyyy> -> ../../../devices/ap/card<xx>/<xx>.<yyyy>
...
card<xx> -> ../../../devices/ap/card<xx>
...
drivers
<drv>card
card<xx> -> ../../../../devices/ap/card<xx>
<drv>queue
<xx>.<yyyy> -> ../../../../devices/ap/card<xx>/<xx>.<yyyy>
...

/sys/devices/ap
card<xx>
<xx>.<yyyy>
driver -> ../../../../bus/ap/drivers/<zzz>queue
...
driver -> ../../../bus/ap/drivers/<drv>card
...

The two digit <xx> field is the card number, the four digit <yyyy>
field is the queue number and <drv> is the name of the device driver,
e.g. "cex4".

For compatability /sys/bus/ap/card<xx> for the old layout has to exist,
including the attributes that used to reside there.

With additional contributions from Harald Freudenberger and
Martin Schwidefsky.

Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: Introduce CEX6 toleration

Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: Fix zcrypt suspend/resume behavior

The device suspend call triggers all ap devices to fetch potentially
available response messages from the queues. Therefore the
corresponding zcrypt device, that is allocated asynchronously after
ap device probing, needs to be fully prepared. This race condition
could lead to uninitialized response buffers while trying to read
from the queues.

Introduce a new callback within the ap layer to get noticed when a
zcrypt device is fully prepared. Additional checks prevent reading
from devices that are not fully prepared.

Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: introduce state machine for the AP bus

Replace the two fields 'unregistered' and 'reset' with a device
state with 5 possible values. Introduce two events for the AP devices,
device poll and device timeout. With the state machine it is easier
to deal with device initialization and suspend/resume. Device polling
is simpler as well, the arkane 'flags' passing is gone.

Reviewd-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: use explicit return code for flushed requests

If a AP device is removed while messages are still pending, the requests
are cancelled by calling the message receive function with an error pointer
for the reply. The message type receive handler recognize this and create
a fake hardware error TYPE82_RSP_CODE / REP82_ERROR_MACHINE_FAILURE.
The message with the hardware error then causes a printk and a return
code of -EAGAIN.

Replace the intricate scheme with an explicit return code for this sitation
and avoid the error message.

Reviewd-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: fix memory leak with ap configuration data

The ap_query_configuration function allocates the ap_config_info
structure, but there is no code to free the structure.
Allocate the structure in the module_init function and free it
again in module_exit.

While we are at it simplify a few functions in regard to the
ap configuration data.

Reviewed-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: remove duplicate low level functions

ap_test_queue, ap_query_facilities, __ap_query_functions all use
the same PQAP(TAPQ) command. Consolidate the three into a single
ap_test_queue function that returns the AP status and the 64-bit
result. The exception table entry for PQAP(TAPQ) can be avoided
if the T bit for the APFT facility is set only if test_facility(15)
indicated that the facility is present.

Integrate ap_query_function into ap_query queue to avoid calling
PQAP(TAPQ) twice.

Reviewed-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: Fixed reset and interrupt handling of AP queues

In case of request timeouts an AP queue reset will be triggered to
recover and reinitialize the AP queue. The previous behavior was an
immediate reset execution regardless of current/pending requests.
Due to newly changed firmware behavior the reset may be delayed, based
on the priority of pending request. The device driver's waiting time
frame was limited, hence it did not received the reset response. As a
consequence interrupts would not be enabled afterwards.

The RAPQ (queue reset) and AQIC (interrupt control) commands will be
treated fully asynchronous now. The device driver will check the reset and
interrupt states periodically, thus it can handle the reinitialization
properly.

Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: Add support for new crypto express (CEX5S) adapter.

Extends the generic cryptographic device driver (zcrypt)
to support the Crypto Express 5S adapter.

Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: Toleration of new crypto hardware

The zcrypt device driver will accept the new crypto adapter
in toleration mode. A new sysfs attribute 'raw_hwtype' will
expose the raw hardware type.

Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@de.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>

s390/zcrypt: support for extended number of ap domains

Extends the number of ap domains within the zcrypt device driver up to 256.
AP domains in the range 00..255 will be detected.

Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: add support for EP11 coprocessor cards

This feature extends the generic cryptographic device driver (zcrypt)
with a new capability to service EP11 requests for the Crypto Express4S
card in EP11 (Enterprise PKCS#11 mode) coprocessor mode.

Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcryt: Handle AP configuration changes

Detect external AP bus configuration changes and request
an AP device rescan.

Signed-off-by: Holger Dengler <hd@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/zcrypt: Add support for CEX4 crypto card

New zcrypt module supports IBM CryptoExpress 4 cards.

Signed-off-by: Holger Dengler <hd@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/ap: Add functiton facility information as AP device attribute.

Add the function facility information as new ap_device and sysfs
attribute. Also make the number of requests in device
queue and in device driver queue accessible in sysfs.

Reviewed-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Holger Dengler <hd@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/ap: configuration information exploitation

Query AP configuration information. Improve performance of AP bus
scans by skipping AP device probing, if the AP deviec is not
configured.

Reviewed-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Holger Dengler <hd@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/comments: unify copyright messages and remove file names

Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.

Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

s390/ap: move receive callback to message struct

Move the receive callback from zdev_driver to ap_message structure to
get a more flexible asynchronous ap message handling.

Signed-off-by: Holger Dengler <hd@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] ap: toleration support for ap device type 10

Add toleration support for ap devices with device type 10.

Signed-off-by: Holger Dengler <hd@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] zcrypt: Introduce check for 4096 bit support.

Implemented an asm in the ap bus and made it accessible for the card
specific parts of the zcrypt driver. Thus when a cex3a is recognized
a check can be performed to dermine whether the card supports 4096 bit
RSA keys.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] zcrypt: add support for cex3 device types

This patch renames the CEX2C2 and CEX2A2 types to CEX3 device types.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Ralph Wuerthner <ralph.wuerthner@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] zcrypt: special command support for cex3 exploitation

Support for special command is implemented in the AP Bus in the NQAP
function __ap_send. This is extended for a further parameter special.
When set, the special bit, in GR0 will be set. Therefor the ap_message
struct is extended for a further bit. Thus calling functions of
__ap_send can use the special parameter in ap_message to give to
__ap_send. Affected is in the first place ap_queue_message, which is
called by the actual card driver. The second part of this support is
that the card driver for the CEX3C needs to set this special bit, when
an according CPRB is sent to the driver.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Ralph Wuerthner <ralph.wuerthner@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] zcrypt: initialize ap_messages for cex3 exploitation

AP messages need to be initialized, before they will be used. Values
will be zeroized. This will be needed later when introducing support
for the special commands.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Ralph Wuerthner <ralph.wuerthner@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] zcrypt: Use of Thin Interrupts

When the machine supports AP adapter interrupts polling will be
switched off at module initialization and the driver will work in
interrupt mode.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] zcrypt: Add additional card IDs to CEX2C and CEX2A

Add support for new micro code load of CEX2C and CEX2A adapters,
which uses different IDs. This patch just adds the IDs to the
existing drivers.

Signed-off-by: Ralph Wuerthner <ralph.wuerthner@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

[S390] zcrypt: Comments and kernel-doc cleanup

Comments, which suggested to be kernel-doc but were not in the right
formatting, have been corrected. Additionally some minor cleanup in
the comments has been done.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

[S390] zcrypt: fix request timeout handling

Under very high load zcrypt requests may timeout while waiting on the
request queue. Modify zcrypt that timeouts are based on crypto adapter
responses. A timeout occurs only if a crypto adapter does not respond
within a given time frame to sumitted requests.

Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] zcrypt: fix possible dead lock in AP bus module

AP bus module uses bus_for_each_dev() in software interrupt context to
poll for completed requests which might cause dead locks. Solution: use
private AP device list for polling in software interrupt context.

Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] zcrypt adjunct processor bus.

Add a bus for the adjunct processor interface. Up to 64 devices can
be connect to the ap bus interface, each device with 16 domains. That
makes 1024 message queues. The interface is asynchronous, the answer
to a message sent to a queue needs to be received at some later point
in time. Unfortunately the interface does not provide interrupts when
a message reply is pending. So the ap bus needs to implement some
fancy polling, each active queue is polled once per 1/HZ second or
continuously if an idle cpus exsists and the poll thread is activ
(see poll_thread parameter).

The ap bus uses the sysfs path /sys/bus/ap and has two bus attributes,
ap_domain and config_time. The ap_domain selects one of the 16 domains
to be used for this system. This limits the maximum number of ap devices
to 64. The config_time attribute contains the number of seconds between
two ap bus scans to find new devices.

The ap bus uses the modalias entries of the form "ap:tN" to autoload
the ap driver for hardware type N. Currently known types are:
3 - PCICC, 4 - PCICA, 5 - PCIXCC, 6 - CEX2A and 7 - CEX2C.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>