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: 7e0bdbe5c2 ("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>
Some cleanup in the s390 zcrypt device driver:
- Removed fragments of pcixx crypto card code. This code
can't be reached anymore because the hardware detection
function does not recognize crypto cards < CEX2 since
commit f56545430736 ("s390/zcrypt: Introduce QACT support
for AP bus devices.")
- Rename of some files and driver names which where still
reflecting pcixx support to cex2a/cex2c.
- Removed all the zcrypt version strings in the file headers.
There is only one place left - the zcrypt.h header file is
now the only place for zcrypt device driver version info.
- Zcrypt version pump up from 2.2.0 to 2.2.1.
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
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>
This patch adds the full CEX6S card support to the zcrypt device
driver. A CEX6A/C/P is detected and displayed as such, the card
and queue device driver code is updated to recognize it and the
relative weight values for CEX4, CEX5 and CEX6 have been updated.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
Crypto requests are very different in complexity and thus runtime.
Also various crypto adapters are differ with regard to the execution
time. Crypto requests can be balanced much better when the request
type and eligible crypto adapters are rated in a more precise
granularity. Therefore, request weights and adapter speed rates for
dedicated requests will be introduced.
Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Now that the message type modules are linked with the zcrypt_api
into a single module the zcrypt_ops_list is initialized by
the module init function of the zcyppt.ko module. After that
the list is static and all message types are present.
Drop the zcrypt_ops_list_lock spinlock and the module handling
in regard to the message types.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
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>
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>
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>
Harald Freudenberger