The safe offline processing may hang forever because it waits for I/O
which can not be started because of the offline flag that prevents new
I/O from being started.

Allow I/O to be started during safe offline processing because in this
special case we take care that the queues are empty before throwing away
the device.
Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

The safe offline processing needs, as well as the normal offline
processing, to be locked against multiple parallel executions. But it
should be able to be overtaken by a normal offline processing to make sure
that the device does not wait forever for outstanding I/O if the user
wants to.

Unfortunately the parallel processing of safe offline and normal offline
might lead to a race situation where both threads report successful
execution to the CIO layer which in turn tries to deregister the kobject
of the device twice. This leads to a

refcount_t: underflow; use-after-free.

error and the device is not able to be set online again afterwards without
a reboot.

Correct the locking of the safe offline processing by doing the following:
	- Use the cdev lock to secure all set and test operations to the
	  device flags.
	- Two safe offline processes are locked against each other using
	  the DASD_FLAG_SAFE_OFFLINE and DASD_FLAG_SAFE_OFFLINE_RUNNING
	  device flags.
	  The differentiation between offline triggered and offline running
	  is needed since the normal offline attribute is owned by CIO and
	  we have to pass over control in between.
	- The dasd_generic_set_offline process handles the offline
	  processing. It is locked against parallel execution using the
	  DASD_FLAG_OFFLINE.
	- Only a running safe offline should be able to be overtaken by a
	  single normal offline. This is ensured by clearing the
	  DASD_FLAG_SAFE_OFFLINE_RUNNING flag when a normal offline
	  overtakes. So this can only happen ones.
	- The safe offline just aborts in this case doing nothing and
	  the normal offline processing finishes as usual.
Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

We have two flags, DASD_FLAG_DEVICE_RO and DASD_FEATURE_READONLY, that
tell us whether a device is read-only. DASD_FLAG_DEVICE_RO is set when a
device is attached as read-only to z/VM and DASD_FEATURE_READONLY is set
when either the corresponding kernel parameter is configured, or the
read-only state is changed via sysfs.
This is valuable information in any case. However, only the feature flag
is being checked at the moment when we display the current state.

Fix this by checking both flags.
Reviewed-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Move the CONFIG_PCI device so that ioremap and iounmap are always
available. This looks safe as there's nothing PCI specific in the
implementation of these functions.

I have designs to use these functions in scatterlist.c where they'd likely
never be called without CONFIG_PCI set, but this is needed to compile
such changes.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Command 'perf list pmu' displays events which contain
an invalid string "(null)=xxx", where xxx is the pmu event
name, for example:
   cpum_cf/AES_BLOCKED_CYCLES,(null)=AES_BLOCKED_CYCLES/
This is not correct, the invalid string should not be
displayed at all.

It is caused by an obsolete term in the
sysfs attribute file for each s390 CPUMF counter event.
Reading from the sysfs file also displays the event
name.

Fix this by omitting the event name.  This patch makes
s390 CPUMF sysfs files consistent with other plattforms.

This is an interface change between user and kernel
but does not break anything. Reading from a counter event
sysfs file should only list terms mentioned in the
/sys/bus/event_source/devices/<cpumf>/format directory.
Name is not listed.
Reported-by: Zvonko Kosic <zvonko.kosic@de.ibm.com>
Signed-off-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Introduce and use p?d_folded() functions to clarify the page table
code a bit more.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

_REGION3_ENTRY_ORIGIN defines a wrong mask which can be used to
extract a segment table origin from a region 3 table entry. It removes
only the lower 11 instead of 12 bits from a region 3 table entry.
Luckily this bit is currently always zero, so nothing bad happened yet.

In order to avoid future bugs just remove the region 3 specific mask
and use the correct generic _REGION_ENTRY_ORIGIN mask.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

The regset functions for guarded storage are supposed to work on
the current task as well. For task == current add the required
load and store instructions for the guarded storage control block.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

All call sites of "stfle" check if the instruction is available before
executing it. Therefore there is no reason to have the corresponding
facility bit set within the architecture level set.
This removes the last more or less odd bit from the list.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

The code in arch/s390/crypto checks for the availability of the
'message security assist' facility on its own, either by using
module_cpu_feature_match(MSA, ...) or by checking the facility
bit during cpacf_query(). Thus setting the MSA facility bit in
gen_facilities.c as hard requirement is not necessary. We can
remove it here, so that the kernel can also run on systems that
do not provide the MSA facility yet (like the emulated environment
of QEMU, for example).
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

When masking an ASCE to get its origin use the corresponding define
instead of the unrelated PAGE_MASK.
This doesn't fix a bug since both masks are identical.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Added some dbf debug messages on failure of the most important
ioctl calls. These messages are only enabled with dbf level
6 (debug) and so do not affect the normal operating mode which
uses level 3 (errors and higher).
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Use proper define instead of open-coding the condition code value.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

I get number of CPUs - 1 kmemleak hits like

unreferenced object 0x37ec6f000 (size 1024):
  comm "swapper/0", pid 1, jiffies 4294937330 (age 889.690s)
  hex dump (first 32 bytes):
    6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
    6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
  backtrace:
    [<000000000034a848>] kmem_cache_alloc+0x2b8/0x3d0
    [<00000000001164de>] __cpu_up+0x456/0x488
    [<000000000016f60c>] bringup_cpu+0x4c/0xd0
    [<000000000016d5d2>] cpuhp_invoke_callback+0xe2/0x9e8
    [<000000000016f3c6>] cpuhp_up_callbacks+0x5e/0x110
    [<000000000016f988>] _cpu_up+0xe0/0x158
    [<000000000016faf0>] do_cpu_up+0xf0/0x110
    [<0000000000dae1ee>] smp_init+0x126/0x130
    [<0000000000d9bd04>] kernel_init_freeable+0x174/0x2e0
    [<000000000089fc62>] kernel_init+0x2a/0x148
    [<00000000008adce2>] kernel_thread_starter+0x6/0xc
    [<00000000008adcdc>] kernel_thread_starter+0x0/0xc
    [<ffffffffffffffff>] 0xffffffffffffffff

The pointer of this data structure is stored in the prefix page of that
CPU together with some extra bits ORed into the the low bits.
Mark the data structure as non-leak.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

When a out of range domain parameter was given, the init function
returned with -EINVAL and the driver was not operational. As the
driver is statically build into the kernel and is able to work
with multiple domains anyway the init function should continue.
Now the user has a chance to write a new default domain value
via sysfs attribute file. Also added two new dbf debug messages
related to the domain value handling.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Select statements in Kconfig do not necessarily enable all required
dependencies and can lead to broken configs. This is also the case
for the "select IUCV" statement within HVC_IUCV:

warning: (HVC_IUCV) selects IUCV which has unmet direct
         dependencies (NET && S390)

Just add the missing "depends on NET" to avoid broken configs.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

The s390_paes and the s390_aes kernel module used just one
config symbol CONFIG_CRYPTO_AES. As paes has a dependency
to PKEY and this requires ZCRYPT the aes module also had
a dependency to the zcrypt device driver which is not true.
Fixed by introducing a new config symbol CONFIG_CRYPTO_PAES
which has dependencies to PKEY and ZCRYPT. Removed the
dependency for the aes module to ZCRYPT.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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

The zcrypt code contains a couple of functions which receive a
"big_endian" argument. All callers naturally pass "1" for big endian,
since s390 is big endian. Therefore get rid of this argument and also
get rid of the cpu_to_le()/cpu_to_be() calls.

This way we get rid of a couple of sparse warnings:

drivers/s390/crypto/zcrypt_cca_key.h:255:34:
 warning: incorrect type in assignment (different base types)
    expected unsigned short [unsigned] ulen
    got restricted __be16 [usertype] <noident>

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

Switch to the improved _install_special_mapping function to install
the vdso mapping. This has two advantages, the arch_vma_name function
is not needed anymore and the vdso vma still has its name after its
memory location has been changed with mremap.
Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

The account_system_index_scaled gets two cputime values, a raw value
derived from CPU timer deltas and a scaled value. The scaled value
is always calculated from the raw value, the code can be simplified
by moving the scale_vtime call into account_system_index_scaled.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

I missed at least these two header files where we can make use of the
generic ones.  vga.h is another one, however that is already addressed
by a patch from Jiri Slaby.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Add missing __user annotations to get rid of a couple of sparse
warnings. All callers actually pass kernel pointers instead of user
space pointers, however the pointers are being used within
KERNEL_DS. So everything is fine.

Corresponding sparse warnings:

drivers/s390/crypto/pkey_api.c:181:41:
 warning: incorrect type in assignment (different address spaces)
    expected char [noderef] <asn:1>*request_control_blk_addr
    got void *<noident>

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

Dynamic stack allocations are considered bad. Get rid of this one
occurrence and use kstrdup() instead.

Also, set the return codes so that we have only one exit where we can
call kfree().
Signed-off-by: Jan Höppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Exploit multiple hardware contexts (queues) that can process
requests in parallel.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Drop the tasklet that was used to complete requests in favor of
block layer helpers that finish the IO on the CPU that initiated
it.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Convert scm_blk to use the blk-mq API. This is just a simple
conversion since we still use a single queue.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Remove CONFIG_SCM_BLOCK_CLUSTER_WRITE and related code. This quirk is
no longer needed on current hardware.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Add __rcu annotations so sparse correctly warns only if "slot" gets
derefenced without using rcu_dereference(). Right now we get warnings
because of the missing annotation:

arch/s390/mm/gmap.c:135:17: warning: incorrect type in assignment (different address spaces)
arch/s390/mm/gmap.c:135:17:    expected void **slot
arch/s390/mm/gmap.c:135:17:    got void [noderef] <asn:4>**
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/crypto/pkey_api.c:1197:12:
  warning: symbol 'pkey_init' was not declared. Should it be static?
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Add missing include statements to make sure that prototypes match
implementation. As reported by sparse:

arch/s390/crypto/arch_random.c:18:1:
  warning: symbol 's390_arch_random_available' was not declared. Should it be static?
arch/s390/kernel/traps.c:279:13: warning:
  symbol 'trap_init' was not declared. Should it be static?
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Add the logic to upgrade the page table for a 64-bit process to
five levels. This increases the TASK_SIZE from 8PB to 16EB-4K.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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

When the association between a queue device and the
driver is released via unbind and later re-associated
the queue device was not operational any more. Reason
was a wrong administration of the card/queue lists
within the ap device driver.

This patch introduces revised card/queue list handling
within the ap device driver: when an ap device is
detected it is initial not added to the card/queue list
any more. With driver probe the card device is added to
the card list/the queue device is added to the queue list
within a card. With driver remove the device is removed
from the card/queue list. Additionally there are some
situations within the ap device live where the lists
need update upon card/queue device release (for example
device hot unplug or suspend/resume).
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Merge tag 'vfio-ccw-20170522' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/vfio-ccw into fixes

Pull vfio-ccw fix from Conelia Huck:
"vfio-ccw: one patch"

* Make some symbols in vfio-ccw static, as detected by sparse.

Make some symbols static to fix sparse warnings like:
drivers/s390/cio/vfio_ccw_ops.c:73:1: warning: symbol 'mdev_type_attr_name' was not declared. Should it be static?
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

For most cases a protection exception in the host (e.g. copy
on write or dirty tracking) on the sie instruction will indicate
an instruction length of 4. Turns out that there are some corner
cases (e.g. runtime instrumentation) where this is not necessarily
true and the ILC is unpredictable.

Let's replace our 4 byte rewind_pad with 3 byte nops to prepare for
all possible ILCs.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Pull pstore fix from Kees Cook:
 "Fix bad EFI vars iterator usage"

* tag 'pstore-v4.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  efi-pstore: Fix read iter after pstore API refactor

During the internal pstore API refactoring, the EFI vars read entry was
accidentally made to update a stack variable instead of the pstore
private data pointer. This corrects the problem (and removes the now
needless argument).

Fixes: 125cc42b ("pstore: Replace arguments for read() API")
Signed-off-by: Kees Cook <keescook@chromium.org>

Pull s390 fixes from Martin Schwidefsky:

 - convert the debug feature to refcount_t

 - reduce the copy size for strncpy_from_user

 - 8 bug fixes

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/virtio: change virtio_feature_desc:features type to __le32
  s390: convert debug_info.ref_count from atomic_t to refcount_t
  s390: move _text symbol to address higher than zero
  s390/qdio: increase string buffer size
  s390/ccwgroup: increase string buffer size
  s390/topology: let topology_mnest_limit() return unsigned char
  s390/uaccess: use sane length for __strncpy_from_user()
  s390/uprobes: fix compile for !KPROBES
  s390/ftrace: fix compile for !MODULES
  s390/cputime: fix incorrect system time