linux-toradex.git/drivers/s390/cio, branch v4.4.73

s390/qdio: clear DSCI prior to scanning multiple input queues

2017-03-15T01:57:12+00:00

commit 1e4a382fdc0ba8d1a85b758c0811de3a3631085e upstream.

For devices with multiple input queues, tiqdio_call_inq_handlers()
iterates over all input queues and clears the device's DSCI
during each iteration. If the DSCI is re-armed during one
of the later iterations, we therefore do not scan the previous
queues again.
The re-arming also raises a new adapter interrupt. But its
handler does not trigger a rescan for the device, as the DSCI
has already been erroneously cleared.
This can result in queue stalls on devices with multiple
input queues.

Fix it by clearing the DSCI just once, prior to scanning the queues.

As the code is moved in front of the loop, we also need to access
the DSCI directly (ie irq->dsci) instead of going via each queue's
parent pointer to the same irq. This is not a functional change,
and a follow-up patch will clean up the other users.

In practice, this bug only affects CQ-enabled HiperSockets devices,
ie. devices with sysfs-attribute "hsuid" set. Setting a hsuid is
needed for AF_IUCV socket applications that use HiperSockets
communication.

Fixes: 104ea556ee7f ("qdio: support asynchronous delivery of storage blocks")
Reviewed-by: Ursula Braun 
Signed-off-by: Julian Wiedmann 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390/cio: fix accidental interrupt enabling during resume

2016-10-31T10:14:00+00:00

commit d53c51f26145657aa7c55fa396f93677e613548d upstream.

Since commit 9f3d6d7 chsc_get_channel_measurement_chars is called with
interrupts disabled during resume from hibernate. Since this function
used spin_unlock_irq, interrupts have been enabled accidentally. Fix
this by using the irqsave variant.

Since we can't guarantee the IRQ-enablement state for all (future/
external) callers, change the locking in related functions to prevent
similar bugs in the future.

Fixes: 9f3d6d7 ("s390/cio: update measurement characteristics")
Signed-off-by: Sebastian Ott 
Reviewed-by: Peter Oberparleiter 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390/cio: update measurement characteristics

2016-09-15T06:27:42+00:00

[ Upstream commit 9f3d6d7a40a178b8a5b5274f4e55fec8c30147c9 ]

Per channel path measurement characteristics are obtained during channel
path registration. However if some properties of a channel path change
we don't update the measurement characteristics.

Make sure to update the characteristics when we change the properties of
a channel path or receive a notification from FW about such a change.

Signed-off-by: Sebastian Ott 
Reviewed-by: Peter Oberparleiter 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

s390/cio: ensure consistent measurement state

2016-09-15T06:27:42+00:00

[ Upstream commit 61f0bfcf8020f02eb09adaef96745d1c1d1b3623 ]

Make sure that in all cases where we could not obtain measurement
characteristics the associated fields are set to invalid values.

Note: without this change the "shared" capability of a channel path
for which we could not obtain the measurement characteristics was
incorrectly displayed as 0 (not shared). We will now correctly
report "unknown" in this case.

Signed-off-by: Sebastian Ott 
Reviewed-by: Peter Oberparleiter 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

s390/cio: fix measurement characteristics memleak

2016-09-15T06:27:42+00:00

[ Upstream commit 0d9bfe9123cfde59bf5c2e375b59d2a7d5061c4c ]

Measurement characteristics are allocated during channel path
registration but not freed during deregistration. Fix this by
embedding these characteristics inside struct channel_path.

Signed-off-by: Sebastian Ott 
Reviewed-by: Peter Oberparleiter 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

s390/cio: allow to reset channel measurement block

2016-08-20T16:09:18+00:00

commit 0f5d050ceaa31b2229102211d60c149f920df3aa upstream.

Prior to commit 1bc6664bdfb949bc69a08113801e7d6acbf6bc3f a call to
enable_cmf for a device for which channel measurement was already
enabled resulted in a reset of the measurement data.

What looked like bugs at the time (a 2nd allocation was triggered
but failed, reset was called regardless of previous failures, and
errors have not been reported to userspace) was actually something
at least one userspace tool depended on. Restore that behavior in
a sane way.

Fixes: 1bc6664bdfb ("s390/cio: use device_lock during cmb activation")
Signed-off-by: Sebastian Ott 
Reviewed-by: Cornelia Huck 
Reviewed-by: Peter Oberparleiter 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390: add support for ipl devices in subchannel sets > 0

2015-11-11T12:56:27+00:00

Allow to ipl from CCW based devices residing in any subchannel set.

Reviewed-by: Michael Holzheu 
Signed-off-by: Sebastian Ott 
Signed-off-by: Martin Schwidefsky

s390/cio: simplify css_generate_pgid

2015-11-09T08:10:48+00:00

Simplify the css_generate_pgid code by using stap() independent of
CONFIG_SMP. For !CONFIG_SMP builds stap() will deliver the address
of the cpu we IPL'ed from (which can be != 0).

Note: the ifdef was likely added to be compatible with _very_ old
machines which we don't support anyway.

Reviewed-by: Peter Oberparleiter 
Signed-off-by: Sebastian Ott 
Signed-off-by: Martin Schwidefsky

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2015-11-04T19:31:31+00:00

Pull s390 updates from Martin Schwidefsky:
 "There is only one new feature in this pull for the 4.4 merge window,
  most of it is small enhancements, cleanup and bug fixes:

   - Add the s390 backend for the software dirty bit tracking.  This
     adds two new pgtable functions pte_clear_soft_dirty and
     pmd_clear_soft_dirty which is why there is a hit to
     arch/x86/include/asm/pgtable.h in this pull request.

   - A series of cleanup patches for the AP bus, this includes the
     removal of the support for two outdated crypto cards (PCICC and
     PCICA).

   - The irq handling / signaling on buffer full in the runtime
     instrumentation code is dropped.

   - Some micro optimizations: remove unnecessary memory barriers for a
     couple of functions: [smb_]rmb, [smb_]wmb, atomics, bitops, and for
     spin_unlock.  Use the builtin bswap if available and make
     test_and_set_bit_lock more cache friendly.

   - Statistics and a tracepoint for the diagnose calls to the
     hypervisor.

   - The CPU measurement facility support to sample KVM guests is
     improved.

   - The vector instructions are now always enabled for user space
     processes if the hardware has the vector facility.  This simplifies
     the FPU handling code.  The fpu-internal.h header is split into fpu
     internals, api and types just like x86.

   - Cleanup and improvements for the common I/O layer.

   - Rework udelay to solve a problem with kprobe.  udelay has busy loop
     semantics but still uses an idle processor state for the wait"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (66 commits)
  s390: remove runtime instrumentation interrupts
  s390/cio: de-duplicate subchannel validation
  s390/css: unneeded initialization in for_each_subchannel
  s390/Kconfig: use builtin bswap
  s390/dasd: fix disconnected device with valid path mask
  s390/dasd: fix invalid PAV assignment after suspend/resume
  s390/dasd: fix double free in dasd_eckd_read_conf
  s390/kernel: fix ptrace peek/poke for floating point registers
  s390/cio: move ccw_device_stlck functions
  s390/cio: move ccw_device_call_handler
  s390/topology: reduce per_cpu() invocations
  s390/nmi: reduce size of percpu variable
  s390/nmi: fix terminology
  s390/nmi: remove casts
  s390/nmi: remove pointless error strings
  s390: don't store registers on disabled wait anymore
  s390: get rid of __set_psw_mask()
  s390/fpu: split fpu-internal.h into fpu internals, api, and type headers
  s390/dasd: fix list_del corruption after lcu changes
  s390/spinlock: remove unneeded serializations at unlock
  ...

s390/cio: de-duplicate subchannel validation

2015-11-03T13:40:50+00:00

cio_validate_io_subchannel() and cio_validate_msg_subchannel() are
identical, as the called functions already take care about the
differences between subchannel types.

Just inline the code into the only user,
cio_validate_subchannel(), instead.

Signed-off-by: Pierre Morel 
Reviewed-by: Cornelia Huck 
Acked-by: Sebastian Ott 
Signed-off-by: Martin Schwidefsky