s390/cio: use while (i--) pattern to clean up

Use more natural while (i--) pattern to clean up allocated resources.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Link: https://lore.kernel.org/r/20240222134501.236871-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/cio: use new address translation helpers

Use virt_to_dma32() and friends to properly convert virtual to physical and
physical to virtual addresses so that "make C=1" does not generate any
warnings anymore.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/cio: remove unneeded DMA zone allocation

Remove GFP_DMA flag when allocating memory to be used for CHSC control
blocks. The CHSC instruction can access memory beyond the DMA zone.

Suggested-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/cio: make sch->lock spinlock pointer a member

The lock member of struct subchannel used to be a spinlock, but became
a pointer to a spinlock with commit 2ec2298412e1 ("[S390] subchannel
lock conversion."). This might have been justified back then, but with
the current state of affairs, there is no reason to manage a separate
spinlock object.

Let's simplify things and pull the spinlock back into struct subchannel.

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Link: https://lore.kernel.org/r/20231101115751.2308307-1-pasic@linux.ibm.com
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

s390/cio: replace deprecated strncpy with strscpy

strncpy() is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.

We expect both `params` and `id` to be NUL-terminated based on their
usage with format strings:

format_node_data(iuparams, iunodeid, &lir->incident_node);
format_node_data(auparams, aunodeid, &lir->attached_node);

switch (lir->iq.class) {
case LIR_IQ_CLASS_DEGRADED:
pr_warn("Link degraded: RS=%02x RSID=%04x IC=%02x "
"IUPARAMS=%s IUNODEID=%s AUPARAMS=%s AUNODEID=%s\n",
sei_area->rs, sei_area->rsid, lir->ic, iuparams,
iunodeid, auparams, aunodeid);

NUL-padding is not required as both `params` and `id` have been memset
to 0:

memset(params, 0, PARAMS_LEN);
memset(id, 0, NODEID_LEN);

Considering the above, a suitable replacement is `strscpy` [2] due to
the fact that it guarantees NUL-termination on the destination buffer
without unnecessarily NUL-padding.

Note that there's no overread bugs in the current implementation as the
string literal "n/a" has a size much smaller than PARAMS_LEN or
NODEID_LEN. Nonetheless, let's favor strscpy().

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20231023-strncpy-drivers-s390-cio-chsc-c-v1-1-8b76a7b83260@google.com
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/cio: fix virtual vs physical address confusion

Fix virtual vs physical address confusion (which currently are the
same).

Reviewed-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/cio: replace zero-length array with flexible-array member

There are numerous patches which convert zero-length arrays with a
flexible-array member. Convert the remaining s390 occurrences.

Suggested-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://github.com/KSPP/linux/issues/78
Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/stp: clock_delta should be signed

clock_delta is declared as unsigned long in various places. However,
the clock sync delta can be negative. This would add a huge positive
offset in clock_sync_global where clock_delta is added to clk.eitod
which is a 72 bit integer. Declare it as signed long to fix this.

Cc: stable@vger.kernel.org
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/cio: dont call css_wait_for_slow_path() inside a lock

Currently css_wait_for_slow_path() gets called inside the chp->lock.
The path-verification-loop of slowpath inside this lock could lead to
deadlock as reported by the lockdep validator.

The ccw_device_get_chp_desc() during the instance of a device-set-online
would try to acquire the same 'chp->lock' to read the chp->desc.
The instance of this function can get called from multiple scenario,
like probing or setting-device online manually. This could, in some
corner-cases lead to the deadlock.

lockdep validator reported this as,

CPU0 CPU1
---- ----
lock(&chp->lock);
lock(kn->active#43);
lock(&chp->lock);
lock((wq_completion)cio);

The chp->lock was introduced to serialize the access of struct
channel_path. This lock is not needed for the css_wait_for_slow_path()
function, so invoke the slow-path function outside this lock.

Fixes: b730f3a93395 ("[S390] cio: add lock to struct channel_path")
Cc: <stable@vger.kernel.org>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/cio: Add support for FCES status notification

Fibre Channel Endpoint-Security event is received as an sei:nt0 type
in the CIO layer. This information needs to be shared with the
CCW device drivers using the path_events callback.

Co-developed-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/cio: Provide Endpoint-Security Mode per CU

Add an interface in the CIO layer to retrieve the information about the
Endpoint-Security Mode (ESM) of the specified CU. The ESM values are
defined as 0-None, 1-Authenticated or 2, 3-Encrypted.

[vneethv@linux.ibm.com: cleaned-up and modified description]

Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/stp: add support for leap seconds

In the current implementation, leap seconds are only synchronized
during the bootup process when the STP clock is synced. If the Leap
second offset (LSO) changes the machine must be rebooted, which is
not desired. This patch adds the required code to handle Leap second
changes during runtime. If the Leap second changes, a Configuration
change machine check is triggered. The STP code than schedules a Leap
second insertion/deletion with do_adjtimex().

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/cio: Helper functions to read CSSID, IID, and CHID

Add helper functions to expose Channel Subsystem ID (CSSID), MIF Image Id
(IID), Channel ID (CHID) and Channel Path ID (CHPID).
These values are required by the qeth driver's exploitation of network-
address-change-notifications to determine which entries belong to this
interface.

Store the Partition identifier in System log, as this may be used to map
a Linux view to a Hardware view for debugging purpose.

Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

s390/cio: Add new Operation Code OC3 to PNSO

Add support for operation code 3 (OC3) of the
Perform-Network-Subchannel-Operations (PNSO) function
of the Channel-Subsystem-Call (CHSC) instruction.

PNSO provides 2 operation codes:
OC0 - BRIDGE_INFO
OC3 - ADDR_INFO (new)

Extend the function calls to *pnso* to pass the OC and
add new response code 0108.

Support for OC3 is indicated by a flag in the css_general_characteristics.

Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

s390/cio, s390/qeth: cleanup PNSO CHSC

CHSC3D (PNSO - perform network subchannel operation) is used for
OC0 (Store-network-bridging-information) as well as for
OC3 (Store-network-address-information). So common fields are renamed
from *brinfo* to *pnso*.
Also *_bridge_host_* is changed into *_addr_change_*, e.g.
qeth_bridge_host_event to qeth_addr_change_event, for the
same reasons.
The keywords in the card traces are changed accordingly.

Remove unused L3 types, as PNSO will only return Layer2 entries.

Make PNSO CHSC implementation more consistent with existing API usage:
Add new function ccw_device_pnso() to drivers/s390/cio/device_ops.c and
the function declaration to arch/s390/include/asm/ccwdev.h, which takes
a struct ccw_device * as parameter instead of schid and calls
chsc_pnso().

PNSO CHSC has no strict relationship to qdio. So move the calling
function from qdio to qeth_l2 and move the necessary structures to a
new file arch/s390/include/asm/chsc.h.

Do response code evaluation only in chsc_error_from_response() and
use return code in all other places. qeth_anset_makerc() was meant to
evaluate the PNSO response code, but never did, because pnso_rc was
already non-zero.

Indentation was corrected in some places.

Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reviewed-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/qdio: pass ISC as parameter to chsc_sadc()

When issuing a SADC for a QDIO device, don't hardcode the ISC but use
whatever is specified in qdio's handler for Adapter Interrupts.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/cio: move struct node_descriptor to cio.h

This allows device drivers (eg. qeth) to use the struct when processing
information retrieved via RCD.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

zcrypt: handle AP Info notification from CHSC SEI command

The current AP bus implementation periodically polls the AP configuration
to detect changes. When the AP configuration is dynamically changed via the
SE or an SCLP instruction, the changes will not be reflected to sysfs until
the next time the AP configuration is polled. The CHSC architecture
provides a Store Event Information (SEI) command to make notification of an
AP configuration change. This patch introduces a handler to process
notification from the CHSC SEI command by immediately kicking off an AP bus
scan-after-event.

Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.ibm.com>
Reviewed-by: Harald Freudenberger <FREUDE@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/cio: add function chsc_sgib()

This patch implements the Set Guest Information Block operation
to request association or disassociation of a Guest Information
Block (GIB) with the Adapter Interruption Facility. The operation
is required to receive GIB alert interrupts for guest adapters
in conjunction with AIV and GISA.

Signed-off-by: Michael Mueller <mimu@linux.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190131085247.13826-9-mimu@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390/chsc: fix packed-not-aligned warnings

Remove attribute packed where possible failing this add proper alignment
information to fix warnings like the one below:

drivers/s390/cio/chsc.c: In function 'chsc_siosl':
drivers/s390/cio/chsc.c:1287:2: warning: alignment 1 of 'struct <anonymous>' is less than 4 [-Wpacked-not-aligned]
} __attribute__ ((packed)) *siosl_area;

Note: this patch should be a nop since non of these structs use auto
storage but allocated pages. However there are changes to the generated
code because of additional padding at the end of some of the structs due
to alignment when memset(foo, 0, sizeof(*foo)) is used.

Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/cio: update chpid descriptor after resource accessibility event

Channel path descriptors have been seen as something stable (as
long as the chpid is configured). Recent tests have shown that the
descriptor can also be altered when the link state of a channel path
changes. Thus it is necessary to update the descriptor during
handling of resource accessibility events.

Cc: <stable@vger.kernel.org>
Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/chsc: query utility strings via fmt3 channel path descriptor

Add support for format 3 channel path descriptors and use them to
gather utility strings.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/cio: rename struct channel_path_desc

Rename struct channel_path_desc to struct channel_path_desc_fmt0
to fit the scheme. Provide a macro for the function wrappers that
gather this and related data from firmware.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390: cio: add SPDX identifiers to the remaining files

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/cio/ 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: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Dong Jia Shi <bjsdjshi@linux.vnet.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>

s390/cio: use cssid for pgid generation

Obtain the real channel subsystem id and use that for the generation
of a unique path group id. Note that this change does not affect the
channel subsystem id as used in the user-visible naming of subchannels
and friends.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Dong Jia Shi <bjsdjshik@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/cio: get rid of variable length array

Use a flexible array instead. The size of the structure is not used
within chsc_sstpi, therefore no change in semantics but one less
sparse warning:

drivers/s390/cio/chsc.c:1219:27: warning: Variable length array is used.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/cio: fix accidental interrupt enabling during resume

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 <sebott@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/chsc: improve channel path descriptor determination

When we fetch channel path descriptors via chsc we use a suboptimal
struct chsc_scpd and adjust that by casting the response to a generic
chsc_response_struct. Simplify the code by improving struct chsc_scpd.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/chsc: sanitize fmt check for chp_desc determination

When fetching channel path descriptors we've only evaluated the rfmt
parameter which could lead us to trigger the chsc even though the
machine doesn't support the specific format or to not trigger the
chsc and report a failure to userspace even though the machine would've
supported it.

Improve these checks and change the parameters of the in-kernel
user to be less confusing.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/cio: make fmt1 channel path descriptor optional

Not all machines / hypervisors support the chsc commands to fetch
the fmt1 descriptor. When these commands fail the channel path would
currently not be available to linux.

Since users of these descriptors can already deal with invalid data
make fetching it optional. The only data that is mandatory for us is
the fmt0 channel path descriptor.

Also make the return code for missing facilities in
chsc_get_channel_measurement_chars consistent to other functions.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/time: STP sync clock correction

The sync clock operation of the channel subsystem call for STP delivers
the TOD clock difference as a result. Use this TOD clock difference
instead of the difference between the TOD timestamps before and after
the sync clock operation.

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

s390/cio: update measurement characteristics

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 <sebott@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/cio: ensure consistent measurement state

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 <sebott@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/cio: fix measurement characteristics memleak

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 <sebott@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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

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

Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/cio: Implement proper Link Incident Record handling

A hardware problem on a FICON link is reported by the Channel Subsystem
to the operating system via a Link Incident Record (LIR). In response,
the operating system should issue a message that enables hardware
service personnel to identify and repair the failing component.

Current Linux LIR handling is broken because LIR data is incorrectly
interpreted and no log message is generated.

This patch fixes Linux LIR handling by implementing a new log message
for LIRs indicating a degraded or non-operational link. Also LIRs are
no longer used to deactivate channel paths because the available data
does not reliably allow to determine the affected channel path.

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/chsc: fix SEI usage on old FW levels

Using a notification type mask for the store event information chsc
is unsupported on some firmware levels. Retry SEI with that mask set
to zero (which is the old way of requesting only channel subsystem
related events).

Cc: <stable@vger.kernel.org>
Reported-and-tested-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/cio: Fix missing subchannels after CHPID configure on

Performing a Channel-Path configure on operation on a Channel-Path ID
(CHPID) does not trigger a scan for subchannels that might have become
available through that CHPID. As a result, some subchannels and
associated I/O devices might be missing. Fix this by adding the missing
scan.

This problem was introduced by commit c820de39, "[S390] cio: Rework
css driver.", but wasn't noticed earlier because the machine usually
also generates a Channel-Report-Word when the first CHPID of a
subchannel is configured on, resulting in a separate scan for that
subchannel. The problem only becomes apparent when this first CHPID is
not working properly and additional working CHPIDs are subsequently
configured on without any effect on the availability of the affected
subchannel.

Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/qdio: bridgeport support - CHSC part

Introduce function for the "Perform network-subchannel operation"
CHSC command with operation code "bridgeport information",
and bit definitions for "characteristics" pertaning to this command.

Signed-off-by: Eugene Crosser <eugene.crosser@ru.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

s390/qdio: bridgeport support - CHSC part

Introduce function for the "Perform network-subchannel operation"
CHSC command with operation code "bridgeport information",
and bit definitions for "characteristics" pertaning to this command.

Signed-off-by: Eugene Crosser <eugene.crosser@ru.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/cio: More efficient handling of CHPID availability events

The CIO layer processes hardware events that indicate that a channel
path has become available by performing a scan of available subchannels
using the Store Subchannel (STSCH) instruction. Performing too many
STSCH instructions in a tight loop can cause high Hypervisor overhead
which can negatively impact the performance of the virtual machine as
a whole.

This patch reduces the number of STSCH instructions performed while
processing a resource accessibility event and while varying a CHPID
online.

In both cases, Linux first performs a STSCH instruction on each unused
subchannel to see if the subchannel has become available. If the STSCH
instruction indicates that the subchannel is available, a full
evaluation of this subchannel is scheduled. Since the full evaluation
includes performing a STSCH instruction, the initial STSCH is
unnecessary and can be removed.

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/qdio: cleanup chsc SADC usage

Move the code to issue the set adapter device controls command to
chsc.c and make it accessible for the qdio code via the wrapper
chsc_sadc.

Reviewed-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/qdio: cleanup chsc SSQD usage

Cleanup the function qdio_setup_get_ssqd. Fix some possible
memleaks and an unchecked allocation and create a wrapper
for SSQD in chsc.c .

Reviewed-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/cio: collect format 1 channel-path description data

Collect format 1 channel-path description data for each CHPID
and update the information in one place.

Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/scm: process availability

Let the bus code process scm availability information and
notify scm device drivers about the new state.

Reviewed-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/chsc: cleanup SEI helper functions

Cleanup the functions used to call SEI.
Also provide !CONFIG_PCI dummys for pci error handling.

Reviewed-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/chsc: fix SEI usage

cbc0dd1 "s390/pci: CHSC PCI support for error and availability events"
introduced a new SEI notification type as part of pci support.
The way SEI was called with nt2 and nt0 consecutive broke the nt0
stuff used for channel subsystem notifications.

The reason why this was broken with the mentioned patch is that you
cannot selectively disable type 0 notifications (so even when asked
for type 2 only, type 0 could be presented).

The way to do it is to tell SEI which types of notification you can
process and -this is the important part- look at the SEI result which
notification type you actually received.

Reviewed-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/pci: CHSC PCI support for error and availability events

Add CHSC store-event-information support for PCI (notfication type 2)
and report error and availability events to the PCI architecture layer.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390: add scm notification

Detect an scm change notification in store event information.
Update affected scm devices and notify their drivers.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/chsc: implement store SCM information

chsc_scm_info will be used to detect all available increments of
storage class memory.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/comments: unify copyright messages and remove file names

Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.

Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

[S390] cio: fix chsc_chp_vary

The functions called by chsc_chp_vary operate on pointers to channel
path ids not channel path links. (This worked by chance since the id
is the first member of the link structure)

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] chsc: process channel-path-availability information

Update affected channel path descriptors when receiving channel path
availability information.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: obtain mdc value per channel path

Add support to accumulate the number of 64K-bytes blocks all paths
to a device at least support for a transport command.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] css: update descriptor after hibernate

Update the channel path descriptors after hibernation.
This is done unlocked, since we are the only active
task at this time.

Note: chsc_determine_base_channel_path_desc is changed
to use spin_lock_irqsave, since it's called with
interrupts disabled in this case.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: update descriptor in chsc_chp_vary

Update the channel path descriptor at the beginning of to the
vary_on operation.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] chsc: use the global page to determine the chp desriptor

chsc_determine_channel_path_desc is called by a wrapper
who allocates a response struct. The response data
is then memcpy'ed to this response struct by
chsc_determine_channel_path_desc.

Change chsc_determine_base_channel_path_desc to use the
global chsc_page and deliver it to the function doing
the actual chsc call. The channel path desriptor is
then directly read from the response data.

As a result we get rid of the additional allocation
for the response struct.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] chsc: consolidate memory allocations

Most wrappers around the channel subsystem call have their own logic
to allocate memory (with proper alignment) or use preallocated or
static memory. This patch converts most users of the channel
subsystem call to use the same preallocated page (proteced by a
spinlock).

Note: The sei_page which is used in our crw handler to call
"store event information" has to coexist, since
a) in crw context, while accessing the sei_page, sleeping is allowed
(which will conflict with the spinlock protection of the chsc_page)
b) in crw context, while accessing the sei_page, channel subsystem
calls are allowed (which itself would require the page).

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] chsc: initialization fixes

This patch fixes:
* kfree vs. free_page usage
* structure definition for determine_css_characteristics
* naming convention for the chsc init function
* deregistration of crw handlers in the cleanup path

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: CHSC SIOSL Support

A Linux interface for the CHSC command
store-I/O-operation-status-and-initiate-logging (SIOSL).
Model-dependent logging within the channel subsystem can be invoked
via a helper function or a writable subchannel device attribute.

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

[S390] cio: fix potential overflow in chpid descriptor

The length filed in the chsc response block (if valid)
has a value of n*(sizeof(chp_desc))+8 (for the response
block header). When we memcopied from the response block
to the actual descriptor we copied 8 bytes too much.
The bug was not revealed since the descriptor is embedded
in struct channel_path.
Since we only write one descriptor at a time ignore the
length value and use sizeof(*desc).

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: allow enable_facility from outside init functions

Prepare chsc_enable_facility to be used from outside init functions.
Use static memory for the chsc call and protect its access by a
spinlock (although there is no concurrent usage).

Cc: <stable@kernel.org>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: fix storage key handling

Some parts of cio do not shift PAGE_DEFAULT_KEY correctly and end up
with an incorrect key in their data structures.
Since the default key is zero this doesn't really matter. However if
somebody would use key-controlled protection for debugging purposes
it would be quite helpful if all of this would work as expected.

Also remove a stale declaration.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] pm: css bus power management callbacks

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: fix rc generation after chsc call

In some situations a rc in __chsc_do_secm will be overwritten
by another one. This shouldn't do harm since todays callers
don't check for _specific_ errors but fix it for the sake of
correctness.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] split/move machine check handler code

Split machine check handler code and move it to cio and kernel code
where it belongs to. No functional change.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] convert cio printks to pr_xxx macros.

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

[S390] cio: Export chsc_error_from_response().

Make chsc_error_from_response() available to chsc callers outside
of chsc.c (namely qdio) to avoid duplicating error checking code.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

[S390] cio: Add chsc subchannel driver.

This patch adds a driver for subchannels of type chsc.

A device /dev/chsc is created which may be used to issue ioctls to:
- obtain information about the machine's I/O configuration
- dynamically change the machine's I/O configuration via
asynchronous chsc commands

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

[S390] cio: Repair chpid event handling.

Passing the affected chpid in chp_event() worked only by
chance since chpid is the first element in res_acc_data.
Make it work properly by generalizing res_acc_data as
chp_link and always passing around a properly filled out
chp_link structure in chp_event().

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

[S390] stp support.

Add support for clock synchronization with the server time protocol.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

[S390] cio: Cleanup crw interface.

Eliminate the need for the machine check handler to call into
the common I/O layer directly by introducing an interface to
register handlers for crws per rsc.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

[S390] cio: Rework css driver.

Rework the css driver methods to provide sane callbacks for
subchannels of all types.

As a bonus, this cleans up and simplyfies the machine check
handling for I/O subchannels a lot.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

[S390] cio: fix parallel cm_enable processing.

It is now possible to trigger cm_enable processing several times in
parallel without causing a kernel panic.

Signed-off-by: Michael Ernst <mernst@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

[S390] cio: Fix race for "fast" path gone/path back situations.

Make sure we wait for previous evaluations triggered by path state
changes to have settled before we manipulate path states again.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

[S390] cio: Clean up chsc response code handling.

This provides unified return codes for common response codes and
also makes the debug feature messages more similar and informational.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] drivers/s390: Add missing "space"

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: reduce cpu utilization during device scan

Minimize calls to cpu intensive function get_subchannel_by_schid()
by introducing function for_each_subchannel_staged() which
temporarily caches the information about registered subchannels
in a bitmap.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: I/O subchannel specific fields.

Some fields may be !0 only for I/O subchannels. Add some checks
where required. Also adapt cio_enable_subchannel() to make the
caller specify the intparm, which makes it more generic.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: css_driver: Use consistent parameters.

Make all callbacks in css_driver take a struct subchannel (and not
a struct device).

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: Reorganize initialization.

- Localize more of the init calls in init_channel_subsystem().
- Print a warning if init_channel_subsystem() failed.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: Clean up messages.

- Remove unneeded messages.
- Move some messages into the debug feature.
- Use dev_* where appropriate.
- Use "cio: " prefix consistently.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: cm_enable memory leak.

We allocage two pages when channel path measurements are enabled
via cm_enable. We must not forget to free them again when
channel path measurements are disabled again.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: fix subchannel channel-path data usage

Ensure that channel-path related subchannel data is only retrieved and
used when it is valid and that it is updated when it may have changed.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: replace subchannel evaluation queue with bitmap

Use a bitmap for indicating which subchannels require evaluation
instead of allocating memory for each evaluation request. This
approach reduces memory consumption during recovery in case of
massive evaluation request occurrence and removes the need for
memory allocation failure handling.

Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: Re-start path verification after aborting internal I/O.

Path verification triggered by changes to the available CHPIDs will be
interrupted by another change but not re-started. This results in an
invalid path mask.
To solve this make sure to completely re-start path verification when
changing the available paths.

Signed-off-by: Stefan Bader <shbader@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: Channel-path configure function.

Add a new attribute to the channel-path sysfs directory through which
channel-path configure operations can be triggered. Also listen for
hardware events requesting channel-path configure operations and
process them accordingly.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

[S390] cio: Introduce separate files for channel-path related code.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

[S390] cio: Allow 0 and 1 as input for channel path status attribute.

Channel path status can now be modified by writing '0' and '1'
to the sysfs status attribute in addition to 'offline' and
'online' respectively.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

[S390] cio: Introduce struct chp_id.

Introduce data type for channel-path IDs.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

[S390] Avoid excessive inlining.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] Cleanup of CHSC event handling.

Change CHSC event handling to be more easily extensible.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: declare hardware structures packed.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: Catch operand exceptions on stsch.

If we have a subchannel id which has been generated via
for_each_subchannel(), it might contain an invalid subchannel set id.
We need to catch the ensuing operand exception by using stsch_err()
instead of stsch() in all possible cases.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: Use device_{create,remove}_bin_file.

Create/remove the channel measurement binary files with
device_{create,remove}_bin_file instead of sysfs_{create,remove}_bin_file.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] subchannel lock conversion.

Convert the subchannel lock to a pointer to a lock. Needed for the dynamic
subchannel mapping patch.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: Retry internal operations after vary off.

If I/O was running on a just varied off chpid, it will be terminated.
If this was a common I/O layer internal I/O, it needs to be retried.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: Use path verification for last path gone after vary off.

If the last path to a device is gone after a chpid has been varied
off, putting it on the slow queue doesn't prevent a device driver
from still attempting to use it (it may stay on the slow queue for a
long time). Instead, trigger a verify event which will prevent I/O
attempts from the device driver immediately.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] Reset infrastructure for re-IPL.

In case of re-IPL and diag308 doesn't work we have to reset all devices
manually and wait synchronously that each reset finished.
This patch adds the necessary infrastucture and the first exploiter of it.

Subsystems that need to add a function that needs to be called at re-IPL
may register/unregister this function via

struct reset_call {
struct reset_call *next;
void (*fn)(void);
};

void register_reset_call(struct reset_call *reset);
void unregister_reset_call(struct reset_call *reset);

When the registered function get called the context is:

- all cpus beside the current one are stopped
- all machine checks and interrupts are disabled
- prefixing is disabled
- a default machine check handler is available for use

The registered functions may not take any locks are sleep.

For the common I/O layer part of this patch:

Introduce a reset_call css_reset that does the following:
- clear all subchannels
- perform a rchp on all channel paths and wait for the resulting
machine checks
This replaces the calls to clear_all_subchannels() and
cio_reset_channel_paths() for kexec and ccw reipl. reipl_ccw_dev() now
uses reipl_find_schid() to determine the subchannel id for a given
device id.
Also remove cio_reset_channel_paths() and friends since they are not
needed anymore.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: remove casts from/to (void *).

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: Remove grace period for vary off chpid.

The grace period handling introduced needless complexity. It didn't
help the dasd driver (which can handle terminated I/O just well),
and it doesn't help for long running channel programs (which won't
complete during the grace period anyway). Terminating I/O using a
path that just disappeared immediately is much more consistent with
what the user expects.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: 0 is a valid chpid.

In order to determine chpid validity, we need to check whether the
corresponding path is specified in the pim.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: always query all paths on path verification.

Reappearing channel paths are sometimes not utilized by CCW devices
because path verification incorrectly relies on path-operational-mask
information which is not updated until a channel path has been used
again.
Modify path verification procedure to always query all available paths
to a device.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: subchannels in no-path state.

Subchannel may incorrectly remain in state no-path after channel paths
have reappeared. Currently the scan for subchannels which are using a
channel path ends at the first occurrence if a full link address was
provided by the channel subsystem. The scan needs to continue over
all subchannels.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: no path after machine check.

Devices enter no-path state after disabling a channel path
via the SE even though another path has been reenabled at the SE.
The devices are set into no-path state before triggering path
verification even though other paths may have become available.
To fix this trigger path verification before setting a device into
no-path state.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: kernel stack overflow.

Use different kind of assignment to make sure gcc doesn't create code
that creates temp variables on the stack, assigns values to it and
copies the content of the whole temp variable to the destination.
This reduces stack usage of e.g. ccwgroup_driver_register from 976
to 48 bytes instead.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] path grouping and path verifications fixes.

1. Multipath devices for which SetPGID is not supported are not handled well.
Use NOP ccws for path verification (sans path grouping) when SetPGID is not
supported.
2. Check for PGIDs already set with SensePGID on _all_ paths (not just the
first one) and try to find a common one. Moan if no common PGID can be
found (and use NOP verification). If no PGIDs have been set, use the css
global PGID (as before). (Rationale: SetPGID will get a command reject if
the PGID it tries to set does not match the already set PGID.)
3. Immediately before reboot, issue RESET CHANNEL PATH (rcp) on all chpids. This
will remove the old PGIDs. rcp will generate solicited CRWs which can be
savely ignored by the machine check handler (all other actions create
unsolicited CRWs).

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Remove obsolete #include <linux/config.h>

Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

[S390] cio chpid offline.

After setting a path to a dasd offline at the SE, I/O hangs on that
dasd for 5 minutes, then continues.
I/O for which an interrupt will not be reported after the channel
path has been disabled was not terminated by the common I/O layer,
causing the dasd MIH to hit after 5 minutes.

Be more aggressive in terminating I/O after setting a channel path
offline. Also make sure to generate a fake irb if the device
driver issues an I/O request after being notified of the killed
I/O and clear residual information from the irb before trying to
start the delayed verification.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] channel measurement fix.

Specify correct sizeof() in chp_measurement_read() and return
correct amount of read data.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[PATCH] s390: enable interrupts on error path

Interrupts can stay disabled if an error occurred in _chp_add(). Use
spin_unlock_irq on the error paths to reenable interrupts.

Signed-off-by: Stefan Bader <shbader@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: fix I/O termination race in cio

Fix a race condition in the I/O termination logic. The race can cause I/O to
a dasd device to fail with no retry left after turning one channel path to the
device off and on multiple times.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: kzalloc() conversion in drivers/s390

Convert all kmalloc + memset sequences in drivers/s390 to kzalloc usage.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: channel path measurements

Gather extended measurements for channel paths from the channel subsystem and
expose them to userspace via a sysfs attribute.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: improve response code handling in chsc_enable_facility()

Rather than checking for some known failures, check positively for the
success response code 0x0001 and return -EIO for unrecognized failure
response codes.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Greg Smith <gsmith@nc.rr.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: fix locking in __chp_add() and s390_subchannel_remove_chpid()

Fix locking in __chp_add() and s390_subchannel_remove_chpid(): Need to
disable/enable because they are always called from a thread (and not
directly from a machine check...)

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: Remove CVS generated information

- Remove all CVS generated information like e.g. revision IDs from
drivers/s390 and include/asm-s390 (none present in arch/s390).

- Add newline at end of arch/s390/lib/Makefile to avoid diff message.

Acked-by: Andreas Herrmann <aherrman@de.ibm.com>
Acked-by: Frank Pavlic <pavlic@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: email-address change

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: multiple subchannel sets support

Add support for multiple subchannel sets. Works with arbitrary devices in
subchannel set 1 and is transparent to device drivers. Although currently
only two subchannel sets are available, this will work with the architectured
maximum number of subchannel sets as well.

Signed-off-by: Cornelia Huck <cohuck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: introduce struct channel_subsystem

struct channel_subsystem encapsulates several per channel subsystem
properties, like status of chpids or the global path group id.

Signed-off-by: Cornelia Huck <cohuck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: introduce for_each_subchannel

for_each_subchannel() is an iterator calling a function for every possible
subchannel id until non-zero is returned. Convert the current iterating
functions to it.

Signed-off-by: Cornelia Huck <cohuck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: introduce struct subchannel_id

This patch introduces a struct subchannel_id containing the subchannel number
(formerly referred to as "irq") and switches code formerly relying on the
subchannel number over to it.

While we're touching inline assemblies anyway, make sure they have correct
memory constraints.

Signed-off-by: Cornelia Huck <cohuck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: resource accessibility event handling

When processing resource accessibility events, continue searching for further
affected subchannels if a link address is provided in the event information.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] Driver Core: drivers/char/raw3270.c - drivers/net/netiucv.c: update device attribute callbacks

Signed-off-by: Yani Ioannou <yani.ioannou@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!