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path: root/drivers/s390/cio
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2020-06-03vfio-ccw: Add trace for CRW eventEric Farman
Since CRW events are (should be) rare, let's put a trace in that routine too. Signed-off-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Message-Id: <20200505122745.53208-9-farman@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2020-06-03vfio-ccw: Wire up the CRW irq and CRW regionFarhan Ali
Use the IRQ to notify userspace that there is a CRW pending in the region, related to path-availability changes on the passthrough subchannel. Signed-off-by: Farhan Ali <alifm@linux.ibm.com> Signed-off-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Message-Id: <20200505122745.53208-8-farman@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2020-06-03vfio-ccw: Introduce a new CRW regionFarhan Ali
This region provides a mechanism to pass a Channel Report Word that affect vfio-ccw devices, and needs to be passed to the guest for its awareness and/or processing. The base driver (see crw_collect_info()) provides space for two CRWs, as a subchannel event may have two CRWs chained together (one for the ssid, one for the subchannel). As vfio-ccw will deal with everything at the subchannel level, provide space for a single CRW to be transferred in one shot. Signed-off-by: Farhan Ali <alifm@linux.ibm.com> Signed-off-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Message-Id: <20200505122745.53208-7-farman@linux.ibm.com> [CH: added padding to ccw_crw_region] Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2020-06-02vfio-ccw: Refactor IRQ handlersEric Farman
To simplify future expansion. Signed-off-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Message-Id: <20200505122745.53208-6-farman@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2020-06-02vfio-ccw: Introduce a new schib regionFarhan Ali
The schib region can be used by userspace to get the subchannel- information block (SCHIB) for the passthrough subchannel. This can be useful to get information such as channel path information via the SCHIB.PMCW fields. Signed-off-by: Farhan Ali <alifm@linux.ibm.com> Signed-off-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Message-Id: <20200505122745.53208-5-farman@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2020-06-02vfio-ccw: Refactor the unregister of the async regionsEric Farman
This is mostly for the purposes of a later patch, since we'll need to do the same thing later. While we are at it, move the resulting function call to ahead of the unregistering of the IOMMU notifier, so that it's done in the reverse order of how it was created. Signed-off-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Message-Id: <20200505122745.53208-4-farman@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2020-06-02vfio-ccw: Register a chp_event callback for vfio-ccwFarhan Ali
Register the chp_event callback to receive channel path related events for the subchannels managed by vfio-ccw. Signed-off-by: Farhan Ali <alifm@linux.ibm.com> Signed-off-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Message-Id: <20200505122745.53208-3-farman@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2020-06-02vfio-ccw: Introduce new helper functions to free/destroy regionsFarhan Ali
Consolidate some of the cleanup code for the regions, so that as more are added we reduce code duplication. Signed-off-by: Farhan Ali <alifm@linux.ibm.com> Signed-off-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Message-Id: <20200505122745.53208-2-farman@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2020-06-02vfio-ccw: Enable transparent CCW IPL from DASDJared Rossi
Remove the explicit prefetch check when using vfio-ccw devices. This check does not trigger in practice as all Linux channel programs are intended to use prefetch. It is expected that all ORBs issued by Linux will request prefetch. Although non-prefetching ORBs are not rejected, they will prefetch nonetheless. A warning is issued up to once per 5 seconds when a forced prefetch occurs. A non-prefetch ORB does not necessarily result in an error, however frequent encounters with non-prefetch ORBs indicate that channel programs are being executed in a way that is inconsistent with what the guest is requesting. While there is currently no known case of an error caused by forced prefetch, it is possible in theory that forced prefetch could result in an error if applied to a channel program that is dependent on non-prefetch. Signed-off-by: Jared Rossi <jrossi@linux.ibm.com> Reviewed-by: Eric Farman <farman@linux.ibm.com> Message-Id: <20200506212440.31323-2-jrossi@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2020-05-28s390/cio, s390/qeth: cleanup PNSO CHSCAlexandra Winter
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>
2020-05-28s390/qdio: remove q->first_to_kickJulian Wiedmann
q->first_to_kick is obsolete, and can be replaced by q->first_to_check. Both cursors start off at 0. Out of the three code paths that update first_to_check, the qdio_inspect_queue() path is irrelevant as it doesn't even touch first_to_kick anymore. This leaves us with the two tasklet-driven code paths. Here any update to first_to_check is followed by a call to qdio_kick_handler(), which advances first_to_kick by the same amount. So the two cursors will differ only for a tiny moment. Drivers have no way of deterministically observing this difference, and thus it doesn't matter which of the cursors we use for reporting an error to q->handler. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-05-28s390/qdio: fix up qdio_start_irq() kerneldocJulian Wiedmann
Document the actual semantics, correcting an old copy & paste mistake. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-05-20s390/qdio: add IRQ reduction for error SBALsJulian Wiedmann
SBALs in PRIMED or ERROR state represent new work on the Input Queue. But while inbound_primed() does all sorts of ACK management for new PRIMED work, the same handling is currently missing for ERROR work. In particular the path for ERROR work doesn't clear up _old_ ACKs. Treat ERROR work the same as PRIMED work, but consider that the QEBSM auto-ACK feature doesn't apply here. So we need to set the ACK manually, as if it was a non-QEBSM device. Note that this doesn't aspire to actually improve performance, the main goal is to just unify the code paths and have consistent behaviour. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-05-20s390/qdio: refactor ACK processing for primed SBALsJulian Wiedmann
inbound_primed() currently has two code paths - one for QEBSM that knows how to deal with multiple ACKs, and a non-QEBSM path that strictly assumes a single ACK on the queue. In preparation for a subsequent patch, slightly adjust the non-QEBSM path so that it can manage a queue with multiple ACKs. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-05-20s390/qdio: simplify overlap calculation on Input refillJulian Wiedmann
Refilling the Input Queue requires additional checks, as the refilled SBALs can overlap with the ACKs that qdio maintains on the queue. This code path is way too complex, and does a whole bunch of wrap-around checks that the modulo arithmetic in sub_buf() takes care of by itself. So shrink down all that code into a few lines of equivalent functionality. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-05-20s390/cio: Remove unused inline function idset_sch_get_firstYueHaibing
commit 8ebd51a705c5 ("s390/cio: idset.c: remove some unused functions") left behind this, remove it Link: https://lkml.kernel.org/r/20200508140643.30540-1-yuehaibing@huawei.com Signed-off-by: YueHaibing <yuehaibing@huawei.com> Reviewed-by: Vineeth Vijayan <vneethv@linux.ibm.com> [vneethv@linux.ibm.com: Slight modification in the title] Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-28s390/qdio: remove always-true conditionJulian Wiedmann
buf_in_between() gets passed q->u.in.ack_start as 'bufnr' parameter. The ack_start always ranges between 0 and QDIO_MAX_BUFFERS_PER_Q - 1, so the subsequent check will always return true. Remove it. 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>
2020-04-28s390/qdio: de-duplicate tiqdio_inbound_processing()Julian Wiedmann
Except for some initial thinint-only steps, the processing is identical to the non-thinint case. So re-use the existing helper. 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>
2020-04-28s390/qdio: keep track of allocated queue countJulian Wiedmann
Knowing how many queues we initially allocated allows us to 1) sanity-check a subsequent qdio_establish() request, and 2) walk the queue arrays without further checks. Apply this while cleanly splitting qdio_free_queues() into two separate helpers. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Reviewed-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-28s390/qdio: roll-back after queue allocation errorJulian Wiedmann
When qdio_allocate_qs() fails, have it deal with its previous allocations. This way qdio_allocate() doesn't need to clean up afterwards. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Reviewed-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-28s390/qdio: do more fine-grained allocation roll-backJulian Wiedmann
Instead of having a catch-all qdio_release_memory() helper, free the individual allocations from the respective error path. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Reviewed-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-28s390/qdio: consolidate thinint init/exitJulian Wiedmann
Wrap the init/exit steps for thinint into a single helper that follows the established naming scheme. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Reviewed-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-28s390/qdio: put thinint indicator after early errorJulian Wiedmann
qdio_establish() calls qdio_setup_thinint() via qdio_setup_irq(). If the subsequent qdio_establish_thinint() fails, we miss to put the DSCI again. Thus the DSCI isn't available for re-use. Given enough of such errors, we could end up with having only the shared DSCI available. Merge qdio_setup_thinint() into qdio_establish_thinint(), and deal with such an error internally. Fixes: 779e6e1c724d ("[S390] qdio: new qdio driver.") 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>
2020-04-28s390/qdio: tear down thinint indicator after early errorJulian Wiedmann
qdio_establish() calls qdio_establish_thinint(), but later has an error exit path that doesn't roll this call back. Fix it. Fixes: 779e6e1c724d ("[S390] qdio: new qdio driver.") 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>
2020-04-28s390/qdio: consistently restore the IRQ handlerJulian Wiedmann
For rolling back after an error, qdio_establish() calls qdio_shutdown(). If the error occurs early enough, then the qdio_irq's state still is QDIO_IRQ_STATE_INACTIVE and qdio_shutdown() does nothing. But at _any_ point where qdio_establish() bails out in this way, qdio_setup_irq() will have already replaced the IRQ handler. This then won't be restored after an early error, and the device can end up being returned to the device driver with qdio's IRQ handler still installed. Slightly reorder qdio_setup_irq() so we can be 100% sure that the IRQ handler was replaced. Then fix the bug in qdio_establish() by calling a helper that rolls back only the IRQ handler modification. Also use the new helper in qdio_shutdown() to keep things in sync, and slightly clean up the locking while doing so. This makes minor semantical changes, but holding setup_mutex gives us sufficient leeway to eg. pull qdio_shutdown_thinint() outside of the ccwdev lock's scope. Fixes: 779e6e1c724d ("[S390] qdio: new qdio driver.") 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>
2020-04-06s390/cio: generate delayed uevent for vfio-ccw subchannelsCornelia Huck
The common I/O layer delays the ADD uevent for subchannels and delegates generating this uevent to the individual subchannel drivers. The vfio-ccw I/O subchannel driver, however, did not do that, and will not generate an ADD uevent for subchannels that had not been bound to a different driver (or none at all, which also triggers the uevent). Generate the ADD uevent at the end of the probe function if uevents were still suppressed for the device. Message-Id: <20200327124503.9794-3-cohuck@redhat.com> Fixes: 63f1934d562d ("vfio: ccw: basic implementation for vfio_ccw driver") Reviewed-by: Eric Farman <farman@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-06s390/cio: avoid duplicated 'ADD' ueventsCornelia Huck
The common I/O layer delays the ADD uevent for subchannels and delegates generating this uevent to the individual subchannel drivers. The io_subchannel driver will do so when the associated ccw_device has been registered -- but unconditionally, so more ADD uevents will be generated if a subchannel has been unbound from the io_subchannel driver and later rebound. To fix this, only generate the ADD event if uevents were still suppressed for the device. Fixes: fa1a8c23eb7d ("s390: cio: Delay uevents for subchannels") Message-Id: <20200327124503.9794-2-cohuck@redhat.com> Reported-by: Boris Fiuczynski <fiuczy@linux.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com> Reviewed-by: Boris Fiuczynski <fiuczy@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-06s390/qdio: clear DSCI early for polling driversJulian Wiedmann
Polling drivers in a configuration with 1 Input Queue currently keep their DSCI armed all the way through the poll cycle, until qdio_start_irq() clears it. _Any_ intermittent QDIO interrupt delivered to tiqdio_thinint_handler() will thus cause 1) the 'adapter_int' statistic to be incremented, 2) a call to tiqdio_call_inq_handlers() for this device, and then 3) the 'int_discarded' statistics to be incremented. This causes overhead & complexity in the IRQ path, along with ambiguity in the statistics. On the other hand the device should be in IRQ avoidance mode during a poll cycle, so there won't be a lot of DSCI ping-pong that this micro-optimization could prevent. So align the DSCI handling with what we already do for devices with multiple Input Queues: clear it right away while processing the IRQ. For the non-polling path this means that we no longer need to handle the 1-queue case separately. 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>
2020-04-06s390/qdio: inline shared_ind()Julian Wiedmann
This is just prep work for a subsequent patch, no functional change. For the non-polling path we can pull the code chunk in front of the for-loop, since it only evaluates to true for a 1-queue configuration. 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>
2020-04-06s390/qdio: remove cdev from init_dataJulian Wiedmann
It's no longer needed. 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>
2020-04-06s390/qdio: allow for non-contiguous SBAL array in init_dataJulian Wiedmann
Upper-layer drivers allocate their SBALs by calling qdio_alloc_buffers() for each individual queue. But when later passing the SBAL addresses to qdio_establish(), they need to be in a single array of pointers. So if the driver uses multiple Input or Output queues, it needs to allocate a temporary array just to present all its SBAL pointers in this layout. This patch slightly changes the format of the QDIO initialization data, so that drivers can pass a per-queue array where each element points to a queue's SBAL array. zfcp doesn't use multiple queues, so the impact there is trivial. For qeth this brings a nice reduction in complexity, and removes a page-sized allocation. 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>
2020-04-06s390/qdio: cleanly split alloc and establishJulian Wiedmann
All that qdio_allocate() actually uses from the init_data is the cdev, and the number of Input and Output Queues. Have the driver pass those as parameters, and defer the init_data processing into qdio_establish(). This includes writing per-device(!) trace entries, and most of the sanity checks. 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>
2020-04-04Merge tag 's390-5.7-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Vasily Gorbik: - Update maintainers. Niklas Schnelle takes over zpci and Vineeth Vijayan common io code. - Extend cpuinfo to include topology information. - Add new extended counters for IBM z15 and sampling buffer allocation rework in perf code. - Add control over zeroing out memory during system restart. - CCA protected key block version 2 support and other fixes/improvements in crypto code. - Convert to new fallthrough; annotations. - Replace zero-length arrays with flexible-arrays. - QDIO debugfs and other small improvements. - Drop 2-level paging support optimization for compat tasks. Varios mm cleanups. - Remove broken and unused hibernate / power management support. - Remove fake numa support which does not bring any benefits. - Exclude offline CPUs from CPU topology masks to be more consistent with other architectures. - Prevent last branching instruction address leaking to userspace. - Other small various fixes and improvements all over the code. * tag 's390-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (57 commits) s390/mm: cleanup init_new_context() callback s390/mm: cleanup virtual memory constants usage s390/mm: remove page table downgrade support s390/qdio: set qdio_irq->cdev at allocation time s390/qdio: remove unused function declarations s390/ccwgroup: remove pm support s390/ap: remove power management code from ap bus and drivers s390/zcrypt: use kvmalloc instead of kmalloc for 256k alloc s390/mm: cleanup arch_get_unmapped_area() and friends s390/ism: remove pm support s390/cio: use fallthrough; s390/vfio: use fallthrough; s390/zcrypt: use fallthrough; s390: use fallthrough; s390/cpum_sf: Fix wrong page count in error message s390/diag: fix display of diagnose call statistics s390/ap: Remove ap device suspend and resume callbacks s390/pci: Improve handling of unset UID s390/pci: Fix zpci_alloc_domain() over allocation s390/qdio: pass ISC as parameter to chsc_sadc() ...
2020-03-27s390/qdio: set qdio_irq->cdev at allocation timeJulian Wiedmann
Set up qdio_irq->cdev right when the qdio_irq struct is allocated, so that all subsequent code can rely on this pointer. Then convert two helper functions to not pass a cdev parameter around. 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>
2020-03-27s390/qdio: remove unused function declarationsJulian Wiedmann
commit 50f769df1c4b ("[S390] qdio: improve inbound buffer acknowledgement") introduced these declarations, but noone added the actual code for them. 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>
2020-03-27s390/ccwgroup: remove pm supportJulian Wiedmann
As s390 no longer supports ARCH_HIBERNATION_POSSIBLE, drop the unused pm ops from the ccwgroup bus driver. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-25s390/qdio: extend polling support to multiple queuesJulian Wiedmann
When the support for polling drivers was initially added, it only considered Input Queue 0. But as QDIO interrupts are actually for the full device and not a single queue, this doesn't really fit for configurations where multiple Input Queues are used. Rework the qdio code so that interrupts for a polling driver are not split up into actions for each queue. Instead deliver the interrupt as a single event, and let the driver decide which queue needs what action. When re-enabling the QDIO interrupt via qdio_start_irq(), this means that the qdio code needs to (1) put _all_ eligible queues back into a state where they raise IRQs, (2) and afterwards check _all_ eligible queues for new work to bridge the race window. On the qeth side of things (as the only qdio polling driver), we can now add CQ polling support to the main NAPI poll routine. It doesn't consume NAPI budget, and to avoid hogging the CPU we yield control after completing one full queue worth of buffers. The subsequent qdio_start_irq() will check for any additional work, and have us re-schedule the NAPI instance accordingly. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-25s390/cio: use fallthrough;Joe Perches
Convert the various uses of fallthrough comments to fallthrough; Done via script Link: https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe.com/ Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23s390/qdio: pass ISC as parameter to chsc_sadc()Julian Wiedmann
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>
2020-03-11s390/irq: replace setup_irq() by request_irq()afzal mohammed
request_irq() is preferred over setup_irq(). Invocations of setup_irq() occur after memory allocators are ready. Per tglx[1], setup_irq() existed in olden days when allocators were not ready by the time early interrupts were initialized. Hence replace setup_irq() by request_irq(). [1] https://lkml.kernel.org/r/alpine.DEB.2.20.1710191609480.1971@nanos Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com> Message-Id: <20200304005049.5291-1-afzal.mohd.ma@gmail.com> [heiko.carstens@de.ibm.com: replace pr_err with panic] Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-09s390/qdio: add tighter controls for IRQ pollingJulian Wiedmann
Once the call to qdio_establish() has completed, qdio is free to deliver data IRQs to the device driver's IRQ poll handler. For qeth (the only qdio driver that currently uses IRQ polling) this is problematic, since the IRQs can arrive before its NAPI instance is even registered. Calling napi_schedule() from qeth_qdio_start_poll() then crashes in various nasty ways. Until recently qeth checked for IFF_UP to drop such early interrupts, but that's fragile as well since it doesn't enforce any ordering. Fix this properly by bringing up the qdio device in IRQS_DISABLED mode, and have the driver explicitly opt-in to receive data IRQs. qeth does so from qeth_open(), which kick-starts a NAPI poll and then calls qdio_start_irq() from qeth_poll(). Also add a matching qdio_stop_irq() in qeth_stop() to switch the qdio dataplane back into a disabled state. Fixes: 3d35dbe6224e ("s390/qeth: don't check for IFF_UP when scheduling napi") CC: Qian Cai <cai@lca.pw> Reported-by: Qian Cai <cai@lca.pw> Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Acked-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-06s390/qdio: export SSQD via debugfsJulian Wiedmann
While we print out various SSQD fields at initialization time, having raw & full access to the current SSQD can help with debugging. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-02-27s390: Replace zero-length array with flexible-array memberGustavo A. R. Silva
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Link: https://lkml.kernel.org/r/20200221150612.GA9717@embeddedor Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-02-27s390/qdio: simplify debugfs codeJulian Wiedmann
There's no need for error handling, the debugfs core is smart enough to deal with IS_ERR() internally. This will also keep us from creating the debugfs files if the device directory doesn't exist. Currently (because irq_ptr->debugfs_dev gets set to NULL on error) the files would be placed into the debugfs root - without any association to their parent device. On teardown, use the debugfs_remove_recursive() helper to avoid keeping track of each created file/directory. 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>
2020-02-27s390/qdio: use QDIO_IRQ_STATE_INACTIVE instead of 0Julian Wiedmann
Don't rely on the numeric value of enum constants. 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>
2020-02-19s390/qdio: reduce access to cdev->private->qdio_dataJulian Wiedmann
Remove all usage of cdev->private->qdio_data that's buried deep in internal code. This should only be used by the exported driver API, which can then pass around a proper qdio_irq pointer. Also trivially merge some initializations with their definitions. 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>
2020-02-19s390/qdio: clean up cdev access in qdio_setup_irq()Julian Wiedmann
Some parts use init_data->cdev, others use irq_ptr->cdev. In the end it's all the same, but unnecessarily confusing. Use a single reference instead. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Reviewed-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-02-19s390/qdio: fill SL with absolute addressesJulian Wiedmann
As the comment says, sl->sbal holds an absolute address. qeth currently solves this through wild casting, while zfcp doesn't care. Handle this properly in the code that actually builds the SL. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Reviewed-by: Alexandra Winter <wintera@linux.ibm.com> Reviewed-by: Steffen Maier <maier@linux.ibm.com> [for qdio] Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-02-17s390/cio: use kobj_to_dev() APIchenqiwu
Use kobj_to_dev() API instead of container_of(). Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: chenqiwu <chenqiwu@xiaomi.com> Signed-off-by: chenqiwu <qiwuchen55@gmail.com> Message-Id: <1581688293-17283-1-git-send-email-qiwuchen55@gmail.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-02-17s390/cio: cio_ignore_proc_seq_next should increase position indexVasily Averin
if seq_file .next fuction does not change position index, read after some lseek can generate unexpected output. Link: https://bugzilla.kernel.org/show_bug.cgi?id=206283 Link: https://lore.kernel.org/r/d44c53a7-9bc1-15c7-6d4a-0c10cb9dffce@virtuozzo.com Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>