Subchannel refcounting was incorrect in some places, especially
a refcount was missing when ccw_device_call_sch_unregister()
was called and the refcount was not correctly switched after
moving devices.
Fix this by establishing the following rules:
- The ccw_device obtains a reference on its parent subchannel
when dev.parent is set and gives it up in its release
function. This is needed because we need a parent reference
for correct refcounting even before the ccw device is (if at
all) registered.
- When calling device_move(), obtain a reference on the new
subchannel before moving the ccw device and give up the
reference on the old parent after moving. This brings the
refcount in line with the first rule.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The current code attempts to get an extra reference count
for online devices by doing a get_device() in ccw_device_online()
and a put_device() in ccw_device_done(). However, this
- incorrectly obtains an extra reference for disconnected
devices becoming available again (since they are already
online)
- needs special checks for css_init_done in order to handle
the console device
- is not obvious and
- may incorretly drop a reference count in ccw_device_done() if
that function is called after path verification for a device
that just became not operational.
So let's just get the reference in ccw_device_set_online() and
drop it in ccw_device_set_offline(). (Unfortunately, we still
need the special case in io_subchannel_probe().)
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Ensure atomicity of ungroup operation to prevent concurrent ungroup
and online processing which may lead to use-after-release situations.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Due to former patches a comment and device id initialization were
split from the addressed function call in io_subchannel_probe.
Move it back to where it belongs.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Values for the sac field have changed - update code accordingly.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Move cio_tpi() to the rest of the CONFIG_CCW_CONSOLE functions to
get rid of this one:
drivers/s390/cio/cio.c:115: warning: 'cio_tpi' defined but not used
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
A kernel compile on 31 bit gives the following warnings in ptrace.c:
arch/s390/kernel/ptrace.c: In function 'peek_user':
arch/s390/kernel/ptrace.c:207: warning: unused variable 'dummy'
arch/s390/kernel/ptrace.c: In function 'poke_user':
arch/s390/kernel/ptrace.c:315: warning: unused variable 'dummy'
Getting rid of the dummy variables removes the warnings.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
For CONFIG_SPARSEMEM_VMEMMAP=y on s390 I get warnings like
init/main.c: In function 'start_kernel':
init/main.c:641: warning: format '%08lx' expects type 'long unsigned int', but argument 2 has type 'int'
The warning can be suppressed with a cast to unsigned long in the
CONFIG_SPARSEMEM_VMEMMAP=y version of __page_to_pfn.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Provide a locking free version of iucv_message_receive and iucv_message_send
that do not call local_bh_enable in a spin_lock_(bh|irqsave)() context.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
This patch introduces a new hypervisor console (HVC) back-end that provides
terminal access over the z/VM inter-user communication vehicle (IUCV).
The z/VM IUCV communication is independent of the regular tcp/ip network
and allows access even if there is no network connection between two
z/VM guest virtual machines.
The z/VM IUCV hypervisor console back-end helps the user to access a
z/VM guest virtual machine that lacks of network connectivity; and thus,
provides a "full-screen" terminal alternative to 3215/3270 terminal sessions.
Use the hvc_iucv=[0..8] kernel boot parameter to specify the number of
HVC terminals using a z/VM IUCV back-end.
A recent version of the s390-tools package is required to establish a
terminal connection to a z/VM IUCV hypervisor console back-end.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This implements just the basic function tracer (_mcount) backend for s390.
The dynamic variant will come later.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
__dasd_cleanup_cqr should be called with request_queue_lock held and
__dasd_block_process_erp with queue_lock
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
SIM sense data are always 32 bit sense data so sense byte 27 bit 0
has not to be set.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
For a large number of I/O requests the values were shifted binary.
The shift was not transparent for the user because the shift value
was not displayed. To make this interface more human readable the
values are shifted decimal and the scale factor is displayed.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Register zfcp with the new /proc/service_level interface to report the
FCP microcode level. When the adapter goes offline or a channel path
disappears, zfcp unregisters, since the microcode version might change
and zfcp does not know about it.
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add a new proc interface /proc/service_levels that allows any code
to report a relevant service level, e.g. the microcode level of
devices, the service level of the hypervisor, etc.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Hipersocket connections can encounter temporary busy conditions.
In case of the busy bit set we retry the SIGA operation immediatelly.
If the busy condition still persists after 100 ms we fail and report
the error to the upper layer. The second stage retry logic is removed.
In case of ongoing busy conditions the upper layer needs to reset the
connection.
The reporting of a SIGA error is now done synchronously to allow the
network driver to requeue the buffers. Also no error trace is created
for the temporary SIGA errors so the error message view is not flooded.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
- Use automatic acknowledgement of incoming buffers in QEBSM mode
- Move ACK for non-QEBSM mode always to the newest buffer to prevent
a race with qdio_stop_polling
- Remove the polling spinlock, the upper layer drivers return new buffers
in the same code path and could not run in parallel
- Don't flood the error log in case of no-target-buffer-empty
- In handle_inbound we check if we would overwrite an ACK'ed buffer, if so
advance the pointer to the oldest ACK'ed buffer so we don't overwrite an
empty buffer in qdio_stop_polling
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
- make qdio_trace a per device view
- remove s390dbf exceptions
- remove CONFIG_QDIO_DEBUG, not needed anymore if we check for the level
before calling sprintf
- use snprintf for dbf entries
- add start markers to see if the dbf view wrapped
- add a global error view for all queues
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The QEBSM instructions are only available for CONFIG_64BIT, they are not
used under 31 bit. Make compiler happy about the false positive:
drivers/s390/cio/qdio_main.c: In function ?qdio_inbound_q_done?:
drivers/s390/cio/qdio_main.c:532: warning: ?state? may be used uninitialized in this function
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add counters for the eqbs and sqbs instructions that indicate how often
we issued the instructions and how often the instructions returned with
less buffers than specified.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
qeth needs to get the port count information before
qdio has allocated a page for the chsc operation.
Extend qdio_get_ssqd_desc() to store the data in the
specified structure.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Changed some symbol names for a better and clearer code.
Signed-off-by: Christian Maaser <cmaaser@de.ibm.com>
Signed-off-by: Felix Beck <beckf@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
stfle will be needed by the ap_bus module to figure out wether the AP
queue adapter interruption facility is installed.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since etr/stp don't need the old smp_call_function semantics anymore
we can convert s390 to the generic IPI infrastructure.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The work function dispatched with schedule_work() can be run twice
on different cpus because run_workqueue clears the WORK_STRUCT_PENDING
bit and then executes the function. Another cpu can call schedule_work()
again and run the work function a second time before the first call
is completed. This patch serialized the etr and stp work function with
a mutex.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This converts the etr and stp code to the new stop_machine interface
which allows to synchronize all cpus without allocating any memory.
This way we get rid of the only reason why we haven't converted s390
to the generic IPI interface yet.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add a vdso to speed up gettimeofday and clock_getres/clock_gettime for
CLOCK_REALTIME/CLOCK_MONOTONIC.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
arch_setup_additional_pages currently gets two arguments, the binary
format descripton and an indication if the process uses an executable
stack or not. The second argument is not used by anybody, it could
be removed without replacement.
What actually does make sense is to pass an indication if the process
uses the elf interpreter or not. The glibc code will not use anything
from the vdso if the process does not use the dynamic linker, so for
statically linked binaries the architecture backend can choose not
to map the vdso.
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The vmcp driver uses the session->mutex for concurrent access of the data
structures. Therefore, the BKL in vmcp_open does not protect against any
other function in the driver.
The BLK in vmcp_open would protect concurrent access to the module init
but all necessary steps ave finished before misc_register is called.
We can safely remove the lock_kernel from vcmp.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Call rebuild_sched_domains instead of arch_reinit_sched_domains if
cpu topology changes. This leaves cpu sets alone which otherwise would
be destroyed.
If and how it makes sense to define cpu sets on a virtualized
architecture is another question.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
On s390 we have ret_from_fork jump not to the "do all work we
normally do on return from syscall" as on x86, ppc, etc., but to the
"do all such work except audit". Historical reasons - the codepath
triggered when we have AUDIT process flag set is separated from the
normall one and they converge at sysc_return, which is the common
part of post-syscall work. And does not include calling audit_syscall_exit() -
that's done in the end of sysc_tracesys path, just before that path jumps
to sysc_return.
IOW, the child returning from fork()/clone()/vfork() doesn't
call audit_syscall_exit() at all, so no matter what we do with its
audit context, we are not going to see the audit entry.
The fix is simple: have ret_from_fork go to the point just past
the call of sys_.... in the 'we have AUDIT flag set' path. There we
have (64bit variant; for 31bit the situation is the same):
sysc_tracenogo:
tm __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
jz sysc_return
la %r2,SP_PTREGS(%r15) # load pt_regs
larl %r14,sysc_return # return point is sysc_return
jg do_syscall_trace_exit
which is precisely what we need - check the flag, bugger off to sysc_return
if not set, otherwise call do_syscall_trace_exit() and bugger off to
sysc_return. r9 has just been properly set by ret_from_fork itself,
so we are fine.
Tested on s390x, seems to work fine. WARNING: it's been about
16 years since my last contact with 3X0 assembler[1], so additional
review would be very welcome. I don't think I've managed to screw it
up, but...
[1] that *was* in another country and besides, the box is dead...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Common code doesn't call arch_update_cpu_topology() anymore on
cpu hotplug. But our architecture backend relied on that in order to
update the cpu_core_map. For machines without cpu topology support
this leads uninitialized cpu_core_maps for later on added cpus.
To solve this just initialize the maps with cpu_possible_map, since
that will be always valid for machines without topology support.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Impact: extend the wakeup tracepoint with the info whether the wakeup was real
Add the information needed to distinguish 'real' wakeups from 'false'
wakeups.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup, avoid warning on X86_64
Fixes this warning on X86_64:
CC arch/x86/kernel/traps.o
arch/x86/kernel/traps.c:695:5: warning: "CONFIG_X86_32" is not defined
Signed-off-by: Jaswinder Singh <jaswinder@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
