This patch introduces a new device driver s390-trng for the
s390 platform which exploits the new PRNO TRNG cpacf
subfunction. The true-random-number-generator is accessible
from userspace, by default visible as /dev/trng. The driver
also registers at the kernel build-in hwrng API to feed the
hwrng with fresh entropy data. This generic device driver
for hardware random data is visible from userspace as
/dev/hwrng.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch introduces s390 specific arch random functionality.
There exists a generic kernel API for arch specific random
number implementation (see include/linux/random.h). Here
comes the header file and a very small static code part
implementing the arch_random_* API based on the TRNG
subfunction coming with the reworked PRNG instruction.
The arch random implementation hooks into the kernel
initialization and checks for availability of the TRNG
function. In accordance to the arch random API all functions
return false if the TRNG is not available. Otherwise the new
high quality entropy source provides fresh random on each
invocation.
The s390 arch random feature build is controlled via
CONFIG_ARCH_RANDOM. This config option located in
arch/s390/Kconfig is enabled by default and appears
as entry "s390 architectural random number generation API"
in the submenu "Processor type and features" for s390 builds.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
There is a new TRNG extension in the subcodes for the cpacf
PRNO function. This patch introduces new defines and a new
cpacf_trng inline function to provide these new features for
other kernel code parts.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The PPNO (Perform Pseudorandom Number Operation) instruction
has been renamed to PRNO (Perform Random Number Operation).
To avoid confusion and conflicts with future extensions with
this instruction (like e.g. provide a true random number
generator) this patch renames all occurences in cpacf.h and
adjusts the only exploiter code which is the prng device
driver and one line in the s390 kvm feature check.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The kernel page table splitting code will split page tables even for
features the CPU does not support. E.g. a CPU may not support the NX
feature.
In order to avoid this, remove those bits from the flags parameter
that correlate with unsupported CPU features within __set_memory(). In
addition add an early exit if the flags parameter does not have any
bits set afterwards.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
With TASK_SIZE now reflecting the maximum size of the address space for
a process the code for arch_get_unmapped_area[_topdown] can be simplified.
Just let the logic pick a suitable address and deal with the page table
upgrade after the address has been selected.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The TASK_SIZE for a process should be maximum possible size of the address
space, 2GB for a 31-bit process and 8PB for a 64-bit process. The number
of page table levels required for a given memory layout is a consequence
of the mapped memory areas and their location.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The guarded storage interface allows to register a control block for
each thread that is activated with the guarded storage broadcast event.
To retrieve the complete state of a process from the kernel a register
set for the stored broadcast control block is required.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add PGSTE manipulation functions:
* set_pgste_bits sets specific bits in a PGSTE
* get_pgste returns the whole PGSTE
* pgste_perform_essa manipulates a PGSTE to set specific storage states
* ESSA_[SG]ET_* macros used to indicate the action for manipulate_pgste
Signed-off-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Reviewed-by: Janosch Frank <frankja@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When vfio_ccw_mdev_reset fails during the remove process of the mdev,
the current implementation simply returns.
The failure indicates that the subchannel device is in a NOT_OPER state,
thus the right thing to do should be removing the mdev.
While we are at here, reverse the condition check to make the code more
concise and readable.
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170412090816.79108-3-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
The CAD instruction never worked quite as expected for the spinlock
code. It has been disabled by default with git commit 61b0b01686,
if the "cad" kernel parameter is specified it is enabled for both user
space and the spinlock code. Leave the option to enable the instruction
for user space but remove it from the spinlock code.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add a couple more __atomic_xxx function to atomic_ops.h and use them
to replace the compare-and-swap inlines in the spinlock code. This
changes the type of the lock value from unsigned int to int.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
There are three different code levels in regard to the identification
of guest samples. They differ in the way the LPP instruction is used.
1) Old kernels without the LPP instruction. The guest program parameter
is always zero.
2) Newer kernels load the process pid into the program parameter with LPP.
The guest program parameter is non-zero if the guest executes in a
process != idle.
3) The latest kernels load ((1UL << 31) | pid) with LPP to make the value
non-zero even for the idle task. The guest program parameter is non-zero
if the guest is running.
All kernels load the process pid to CR4 on context switch. The CPU sampling
code uses the value in CR4 to decide between guest and host samples in case
the guest program parameter is zero. The three cases:
1) CR4==pid, gpp==0
2) CR4==pid, gpp==pid
3) CR4==pid, gpp==((1UL << 31) | pid)
The load-control instruction to load the pid into CR4 is expensive and the
goal is to remove it. To distinguish the host CR4 from the guest pid for
the idle process the maximum value 0xffff for the PASN is used.
This adds a fourth case for a guest OS with an updated kernel:
4) CR4==0xffff, gpp=((1UL << 31) | pid)
The host kernel will have CR4==0xffff and will use (gpp!=0 || CR4!==0xffff)
to identify guest samples. This works nicely with all 4 cases, the only
possible issue would be a guest with an old kernel (gpp==0) and a process
pid of 0xffff. Well, don't do that..
Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Users complained that they are hitting the limit of 64 functions (some
physical functions can spawn lots of virtual functions). Double the
default limit. With the latest savings in static data usage this
increases the image size by only 520 bytes.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Commit c506fff3d3 ("s390/pci: resize iomap") reduced the iomap
to NR_FUNCTIONS * PCI_BAR_COUNT elements. Since we only support
functions with 64bit BARs we can cut that number in half.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The 32-bit lctl instruction is quite a bit slower than the 64-bit
counter part lctlg. Use the faster instruction.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull vfio-ccw branch to add the basic channel I/O passthrough
intrastructure based on vfio.
The focus is on supporting dasd-eckd(cu_type/dev_type = 0x3990/0x3390)
as the target device.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Although Linux does not use format-0 channel command words (CCW0)
these are a non-optional part of the platform spec, and for the sake
of platform compliance, and possibly some non-Linux guests, we have
to support CCW0.
Making the kernel execute a format 0 channel program is too much hassle
because we would need to allocate and use memory which can be addressed
by 24 bit physical addresses (because of CCW0.cda). So we implement CCW0
support by translating the channel program into an equivalent CCW1
program instead.
Based upon an orginal patch by Kai Yue Wang.
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170317031743.40128-16-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
To provide user-space a set of interfaces to:
1. pass in a ccw program to perform an I/O operation.
2. read back I/O results of the completed I/O operations.
We introduce an MMIO region for the vfio-ccw device here.
This region is defined to content:
1. areas to store arguments that an ssch required.
2. areas to store the I/O results.
Using pwrite/pread to the device on this region, a user-space program
could write/read data to/from the vfio-ccw device.
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170317031743.40128-8-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Introduce ccwchain structure and helper functions that can be used to
handle a channel program issued from a virtual machine.
The following limitations apply:
1. Supports only prefetch enabled mode.
2. Supports idal(c64) ccw chaining.
3. Supports 4k idaw.
4. Supports ccw1.
5. Supports direct ccw chaining by translating them to idal ccws.
CCW translation requires to leverage the vfio_(un)pin_pages interfaces
to pin/unpin sets of mem pages frequently. Currently we have a lack of
support to do this in an efficient way. So we introduce pfn_array data
structure and helper functions to handle pin/unpin operations here.
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170317031743.40128-6-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
The return code of hw_perf_event_update() is not evaluated by
its callers. Hence, simplify the function by removing the
return code.
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Make clear that the event definitions relate to the counter
facility (cf) and not to the sampling facility (sf).
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add the event names for the IBM z13/z13s specific CPU-MF counters.
Also improve the merging of the generic and model specific events
so that their sysfs attribute definitions completely reside in
memory. Hence, flagging the generic event attribute definitions
as initdata too.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Complete the IBM z13 support and support counters from the
MT-diagnostic counter set. Note that this counter set is
available only if SMT is enabled.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The validate_event() function just checked for reserved counters
in particular CPU-MF counter sets. Because the number of counters
in counter sets vary among different hardware models, remove the
explicit check to tolerate new models.
Reserved counters are not accounted and, thus, will return zero.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use the highest counter number that can be specified for the
ecctr (extract CPU counter) instruction for perf.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Deferred struct page initialization works on s390. However it makes
only sense for the fake numa case, since the kthreads that initialize
struct pages are started per node. Without fake numa there is just a
single node and therefore no gain.
However there is no reason to not enable this feature. Therefore
select the config option and enable the feature in all config files.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
