aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/s390/cio/css.c (follow)
AgeCommit message (Collapse)AuthorFilesLines
2019-10-10s390/cio: fix virtio-ccw DMA without PVHalil Pasic1-1/+6
Commit 37db8985b211 ("s390/cio: add basic protected virtualization support") breaks virtio-ccw devices with VIRTIO_F_IOMMU_PLATFORM for non Protected Virtualization (PV) guests. The problem is that the dma_mask of the ccw device, which is used by virtio core, gets changed from 64 to 31 bit, because some of the DMA allocations do require 31 bit addressable memory. For PV the only drawback is that some of the virtio structures must end up in ZONE_DMA because we have the bounce the buffers mapped via DMA API anyway. But for non PV guests we have a problem: because of the 31 bit mask guests bigger than 2G are likely to try bouncing buffers. The swiotlb however is only initialized for PV guests, because we don't want to bounce anything for non PV guests. The first such map kills the guest. Since the DMA API won't allow us to specify for each allocation whether we need memory from ZONE_DMA (31 bit addressable) or any DMA capable memory will do, let us use coherent_dma_mask (which is used for allocations) to force allocating form ZONE_DMA while changing dma_mask to DMA_BIT_MASK(64) so that at least the streaming API will regard the whole memory DMA capable. Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com> Suggested-by: Robin Murphy <robin.murphy@arm.com> Fixes: 37db8985b211 ("s390/cio: add basic protected virtualization support") Link: https://lore.kernel.org/lkml/20190930153803.7958-1-pasic@linux.ibm.com Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-09-23s390/cio: exclude subchannels with no parent from pseudo checkVasily Gorbik1-0/+2
ccw console is created early in start_kernel and used before css is initialized or ccw console subchannel is registered. Until then console subchannel does not have a parent. For that reason assume subchannels with no parent are not pseudo subchannels. This fixes the following kasan finding: BUG: KASAN: global-out-of-bounds in sch_is_pseudo_sch+0x8e/0x98 Read of size 8 at addr 00000000000005e8 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.3.0-rc8-07370-g6ac43dd12538 #2 Hardware name: IBM 2964 NC9 702 (z/VM 6.4.0) Call Trace: ([<000000000012cd76>] show_stack+0x14e/0x1e0) [<0000000001f7fb44>] dump_stack+0x1a4/0x1f8 [<00000000007d7afc>] print_address_description+0x64/0x3c8 [<00000000007d75f6>] __kasan_report+0x14e/0x180 [<00000000018a2986>] sch_is_pseudo_sch+0x8e/0x98 [<000000000189b950>] cio_enable_subchannel+0x1d0/0x510 [<00000000018cac7c>] ccw_device_recognition+0x12c/0x188 [<0000000002ceb1a8>] ccw_device_enable_console+0x138/0x340 [<0000000002cf1cbe>] con3215_init+0x25e/0x300 [<0000000002c8770a>] console_init+0x68a/0x9b8 [<0000000002c6a3d6>] start_kernel+0x4fe/0x728 [<0000000000100070>] startup_continue+0x70/0xd0 Cc: stable@vger.kernel.org Reviewed-by: Sebastian Ott <sebott@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-12Merge tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-coreLinus Torvalds1-2/+2
Pull driver core and debugfs updates from Greg KH: "Here is the "big" driver core and debugfs changes for 5.3-rc1 It's a lot of different patches, all across the tree due to some api changes and lots of debugfs cleanups. Other than the debugfs cleanups, in this set of changes we have: - bus iteration function cleanups - scripts/get_abi.pl tool to display and parse Documentation/ABI entries in a simple way - cleanups to Documenatation/ABI/ entries to make them parse easier due to typos and other minor things - default_attrs use for some ktype users - driver model documentation file conversions to .rst - compressed firmware file loading - deferred probe fixes All of these have been in linux-next for a while, with a bunch of merge issues that Stephen has been patient with me for" * tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits) debugfs: make error message a bit more verbose orangefs: fix build warning from debugfs cleanup patch ubifs: fix build warning after debugfs cleanup patch driver: core: Allow subsystems to continue deferring probe drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT arch_topology: Remove error messages on out-of-memory conditions lib: notifier-error-inject: no need to check return value of debugfs_create functions swiotlb: no need to check return value of debugfs_create functions ceph: no need to check return value of debugfs_create functions sunrpc: no need to check return value of debugfs_create functions ubifs: no need to check return value of debugfs_create functions orangefs: no need to check return value of debugfs_create functions nfsd: no need to check return value of debugfs_create functions lib: 842: no need to check return value of debugfs_create functions debugfs: provide pr_fmt() macro debugfs: log errors when something goes wrong drivers: s390/cio: Fix compilation warning about const qualifiers drivers: Add generic helper to match by of_node driver_find_device: Unify the match function with class_find_device() bus_find_device: Unify the match callback with class_find_device ...
2019-07-02s390/cio: introduce driver_override on the css busCornelia Huck1-0/+53
Sometimes, we want to control which of the matching drivers binds to a subchannel device (e.g. for subchannels we want to handle via vfio-ccw). For pci devices, a mechanism to do so has been introduced in 782a985d7af2 ("PCI: Introduce new device binding path using pci_dev.driver_override"). It makes sense to introduce the driver_override attribute for subchannel devices as well, so that we can easily extend the 'driverctl' tool (which makes use of the driver_override attribute for pci). Note that unlike pci we still require a driver override to match the subchannel type; matching more than one subchannel type is probably not useful anyway. Signed-off-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Reviewed-by: Sebastian Ott <sebott@linux.ibm.com> Signed-off-by: Sebastian Ott <sebott@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-06-24bus_find_device: Unify the match callback with class_find_deviceSuzuki K Poulose1-2/+2
There is an arbitrary difference between the prototypes of bus_find_device() and class_find_device() preventing their callers from passing the same pair of data and match() arguments to both of them, which is the const qualifier used in the prototype of class_find_device(). If that qualifier is also used in the bus_find_device() prototype, it will be possible to pass the same match() callback function to both bus_find_device() and class_find_device(), which will allow some optimizations to be made in order to avoid code duplication going forward. Also with that, constify the "data" parameter as it is passed as a const to the match function. For this reason, change the prototype of bus_find_device() to match the prototype of class_find_device() and adjust its callers to use the const qualifier in accordance with the new prototype of it. Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrew Lunn <andrew@lunn.ch> Cc: Andreas Noever <andreas.noever@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Corey Minyard <minyard@acm.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Kershner <david.kershner@unisys.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: David Airlie <airlied@linux.ie> Cc: Felipe Balbi <balbi@kernel.org> Cc: Frank Rowand <frowand.list@gmail.com> Cc: Grygorii Strashko <grygorii.strashko@ti.com> Cc: Harald Freudenberger <freude@linux.ibm.com> Cc: Hartmut Knaack <knaack.h@gmx.de> Cc: Heiko Stuebner <heiko@sntech.de> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jonathan Cameron <jic23@kernel.org> Cc: "James E.J. Bottomley" <jejb@linux.ibm.com> Cc: Len Brown <lenb@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michael Jamet <michael.jamet@intel.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Peter Oberparleiter <oberpar@linux.ibm.com> Cc: Sebastian Ott <sebott@linux.ibm.com> Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Cc: Yehezkel Bernat <YehezkelShB@gmail.com> Cc: rafael@kernel.org Acked-by: Corey Minyard <minyard@acm.org> Acked-by: David Kershner <david.kershner@unisys.com> Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Acked-by: Wolfram Sang <wsa@the-dreams.de> # for the I2C parts Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-15s390/airq: use DMA memory for adapter interruptsHalil Pasic1-0/+1
Protected virtualization guests have to use shared pages for airq notifier bit vectors, because the hypervisor needs to write these bits. Let us make sure we allocate DMA memory for the notifier bit vectors by replacing the kmem_cache with a dma_cache and kalloc() with cio_dma_zalloc(). Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Reviewed-by: Sebastian Ott <sebott@linux.ibm.com> Reviewed-by: Michael Mueller <mimu@linux.ibm.com> Tested-by: Michael Mueller <mimu@linux.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-06-15s390/cio: introduce DMA pools to cioHalil Pasic1-4/+129
To support protected virtualization cio will need to make sure the memory used for communication with the hypervisor is DMA memory. Let us introduce one global pool for cio. Our DMA pools are implemented as a gen_pool backed with DMA pages. The idea is to avoid each allocation effectively wasting a page, as we typically allocate much less than PAGE_SIZE. Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Reviewed-by: Sebastian Ott <sebott@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Michael Mueller <mimu@linux.ibm.com> Tested-by: Michael Mueller <mimu@linux.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2018-07-17s390/css: reduce stsch callsSebastian Ott1-18/+49
Both css_evaluate_new_subchannel and cio_validate_subchannel used stsch and css_sch_is_valid to check for a valid device. Reduce stsch calls during subchannel evaluation by re-using schib data. Also the type/devno valid information is only checked once. 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>
2018-07-17s390/css: validate subchannel prior to allocationSebastian Ott1-3/+8
In css_alloc_subchannel we allocate the subchannel and do a validation of the subchannel (to decide if we should look for devices via this subchannel). On a typical LPAR we find lots of subchannels to be invalid (because there is no device attached or the device is blacklisted) leading to lots of useless kmalloc and kfree calls. This patch changes the order to only allocate the subchannels that have been found valid. 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>
2018-07-17s390/css: start the subchannel evaluation earlierSebastian Ott1-4/+5
The css bus code uses 2 initcalls: channel_subsystem_init to initialize internal data and channel_subsystem_init_sync to start scanning for devices and wait for it to finish. The start scanning for devices part is moved to the first initcall such that more work happens in parallel. Signed-off-by: Sebastian Ott <sebott@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-17s390/cio: ensure that a chpid is registered only onceSebastian Ott1-2/+1
Improve locking in chp_new to make sure that we don't register the same chpid twice. Chpid registration was synchronized via the machine check handler thread but we also have codepaths to look for new chpids triggered independent of that thread (during IPL or resume from hibernate). 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>
2018-01-09treewide: Use DEVICE_ATTR_ROJoe Perches1-4/+4
Convert DEVICE_ATTR uses to DEVICE_ATTR_RO where possible. Done with perl script: $ git grep -w --name-only DEVICE_ATTR | \ xargs perl -i -e 'local $/; while (<>) { s/\bDEVICE_ATTR\s*\(\s*(\w+)\s*,\s*\(?(?:\s*S_IRUGO\s*|\s*0444\s*)\)?\s*,\s*\1_show\s*,\s*NULL\s*\)/DEVICE_ATTR_RO(\1)/g; print;}' Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Robert Jarzmik <robert.jarzmik@free.fr> Acked-by: Sagi Grimberg <sagi@grimberg.me> Acked-by: Zhang Rui <rui.zhang@intel.com> Acked-by: Harald Freudenberger <freude@linux.vnet.ibm.com> Acked-by: Jani Nikula <jani.nikula@intel.com> Acked-by: Corey Minyard <cminyard@mvista.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-24s390: drivers: Remove redundant license textGreg Kroah-Hartman1-2/+0
Now that the SPDX tag is in all drivers/s390/ files, that identifies the license in a specific and legally-defined manner. So the extra GPL text wording can be removed as it is no longer needed at all. This is done on a quest to remove the 700+ different ways that files in the kernel describe the GPL license text. And there's unneeded stuff like the address (sometimes incorrect) for the FSF which is never needed. No copyright headers or other non-license-description text was removed. Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Cc: Julian Wiedmann <jwi@linux.vnet.ibm.com> Cc: Ursula Braun <ubraun@linux.vnet.ibm.com> Cc: Cornelia Huck <cohuck@redhat.com> Cc: Halil Pasic <pasic@linux.vnet.ibm.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.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>
2017-11-24s390: cio: add SPDX identifiers to the remaining filesGreg Kroah-Hartman1-0/+1
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>
2017-06-12s390/cio: introduce io_subchannel_typeSebastian Ott1-0/+49
The sysfs attributes implemented by the vfio_ccw driver are also implemented by the io_subchannel driver. Move these into a device_type which is set by the css bus. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-01-16s390/cio: remove unused struct memberSebastian Ott1-1/+0
Remove an unused member of struct channel subsystem. 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>
2017-01-16s390/cio: export real cssidSebastian Ott1-0/+22
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>
2017-01-16s390/cio: css initialization cleanupSebastian Ott1-56/+47
Simplify error handling during css initialization by moving the error handling code to setup_css (which now cleans up after itself). Also remove the odd special cleanup handling of the pseudo_subchannel. 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>
2017-01-16s390/cio: css attribute cleanupSebastian Ott1-28/+29
Cleanup the code to handle the css device attribute. Move everything to an attribute group to let the driver core handle attribute creation and removal. 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>
2017-01-16s390/cio: use cssid for pgid generationSebastian Ott1-2/+4
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>
2017-01-16s390/cio: clarify cssid usageSebastian Ott1-19/+11
Currently the cssid in various structures is used as the id of the respective channel subsystem. Sometimes however we call the index in the channel_subsystems array cssid. In some places the id is even used as the index. Provide a new define MAX_CSS_IDX and use it where appropriate. In addition to that provide a dummy function to find a channel subsystem by its id and a macro to iterate over the channel subsystems. 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>
2016-10-31s390: cio: make it explicitly non-modularPaul Gortmaker1-3/+3
The Makefile currently controlling compilation of this code is: obj-y += airq.o blacklist.o chsc.o cio.o css.o chp.o idset.o isc.o \ fcx.o itcw.o crw.o ccwreq.o trace.o ioasm.o ccw_device-objs += device.o device_fsm.o device_ops.o ccw_device-objs += device_id.o device_pgid.o device_status.o obj-y += ccw_device.o cmf.o ...meaning that the files here are not being built as modular. Lets remove the couple traces of modular infrastructure use, so that when reading the code there is no doubt it is builtin-only. Since module_init translates to device_initcall in the non-modular case, the init ordering remains unchanged with this commit. Also note that MODULE_DEVICE_TABLE is a no-op for non-modular code. We delete the MODULE_LICENSE tag etc. since all that information was (or is now) contained at the top of the file in the comments. We replace module.h with export.h where the file does export some symbols. Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Arnd Bergmann <arndb@de.ibm.com> Cc: linux-s390@vger.kernel.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-12-18s390/cio: Remove unused inline assembliesPeter Oberparleiter1-1/+1
There is no longer a need to maintain two versions of the same inline assembly - one with exception handling, and one without - so get rid of the duplicates and adjust names accordingly. This applies to stsch_err and msch_err which are now renamed to stsch and msch respectively, while the original msch function is removed. Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-09s390/cio: simplify css_generate_pgidSebastian Ott1-5/+0
Simplify the css_generate_pgid code by using stap() independent of CONFIG_SMP. For !CONFIG_SMP builds stap() will deliver the address of the cpu we IPL'ed from (which can be != 0). Note: the ifdef was likely added to be compatible with _very_ old machines which we don't support anyway. Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-03s390/css: unneeded initialization in for_each_subchannelPierre Morel1-1/+0
The ret variable is always set by the fn function. There is no need to initialize it. Signed-off-by: Pierre Morel <pmorel@linux.vnet.ibm.com> Reviewed-By: Sascha Silbe <silbe@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14s390/cio: reactivate cmf after hibernateSebastian Ott1-0/+1
During resume from hibernate we already reenable measurement block updates on a per device basis. In addition to that we also need to activate channel measurement globally using the set channel monitor instruction. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16s390/css: Prevent unnecessary allocation in subchannel loopPeter Oberparleiter1-1/+9
Subchannel looping function for_each_subchannel_staged() allocates a subchannel-ID-bitmap to efficiently iterate over the list of known and unknown subchannels. Since this function is also used to iterate over known-subchannels only, optimize that case by not requiring the ID-bitmap allocation and falling back to simple bus_for_each_dev() looping. 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>
2013-12-16s390/cio: Delay scan for newly available I/O devicesPeter Oberparleiter1-6/+7
The CIO layer scans for newly available I/O devices 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. A subchannel scan is triggered for example during a hardware event that indicates that a channel path has become available. It is also triggered by the DASD device driver for each device that is set online. This patch reduces the number of STSCH instructions being performed by delaying the start of the actual subchannel scan by 1 second. Multiple scan requests that are scheduled during this time will be merged into a single scan loop. The trade-off consists of a short delay that is introduced between the time that the event is processed and a newly available device becoming usable. This delay should be acceptable since it only affects devices that have not been in use before. 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>
2013-12-16s390/cio: Relax subchannel scan loopPeter Oberparleiter1-0/+3
The CIO layer scans for newly available I/O devices by performing a scan of available subchannels using the Store Subchannel (STSCH) instruction. This processing can take a significant amount of time during which no other task can run on the same CPU (unless CONFIG_PREEMPT has been enabled). As a result, scheduling latencies for other tasks are increased noticeably, especially on a single-CPU system. Fix this problem by explicitly allowing other tasks to be scheduled each time a subchannel has been processed. 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>
2013-08-30s390/cio: fix unlocked access of global bitmapSebastian Ott1-0/+2
Access to the slow_subchannel_set has to be secured via the slow_subchannel_lock. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22s390: replace strict_strtoul() with kstrtoul()Jingoo Han1-1/+1
The usage of strict_strtoul() is not preferred, because strict_strtoul() is obsolete. Thus, kstrtoul() should be used. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-04-17s390/css: move subchannel lock allocationSebastian Ott1-8/+28
cio_validate_subchannel is used to do some basic checks to find out if it's worth to further investigate a subchannel. Move the allocation and initialization of the subchannels locks to css_alloc_subchannel. Clean up the functions involved while at it. 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>
2013-04-17s390/css: remove unused function definitionsSebastian Ott1-2/+2
Make css_probe_device static and remove an unimplemented prototype. 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>
2013-04-17s390/css: introduce cio_register_early_subchannelsSebastian Ott1-19/+12
Use cio_register_early_subchannels to register early subchannels which are already in use. Call this function before we do the actual subchannel scanning loop. This helps us to get rid of some more special cases regarding the console subchannel. 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>
2013-04-17s390/cio: get rid of static console subchannelSebastian Ott1-14/+9
Remove the static console subchannel (and friends) and use dynamic allocation for these structures. With this change the console subchanel is treated (mostly) like any other subchannel and we can remove some special cases. 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>
2013-04-17s390/cio: split subchannel registrationSebastian Ott1-19/+18
Split the subchannel registration in device_initialize and device_add and move the initialization part inside the allocation function. With this change we can use refcounting during the complete lifespan of a subchannel which is important for devices where we do the actually registration at a later time. 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>
2013-04-17s390/cio: collect format 1 channel-path description dataPeter Oberparleiter1-3/+2
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>
2013-02-14s390/time: rename tod clock access functionsHeiko Carstens1-1/+1
Fix name clash with some common code device drivers and add "tod" to all tod clock access function names. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-10-18s390/css: stop stsch loop after cc 3Sebastian Ott1-1/+6
Receiving cc=3 from store subchannel means 2 things: * the subchannel is not provided * there are no further subchannels in this subchannel set With this patch we abort the store subchannel loop after cc=3 (or an exception) and clear the subsequent bits in the subchannel id set. Reported-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Acked-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-09-26s390/css: export css_sched_sch_todoSebastian Ott1-0/+1
Allow subchannel drivers build as a module to schedule subchannel work. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-12-01[S390] hibernate: directly trigger subchannel evaluationSebastian Ott1-45/+59
Using the generic css_schedule_eval to evaluate subchannels while resuming from hibernation is very slow when used with many devices. Provide a new evaluation trigger which exploits css_sched_sch_todo and use this in the resume callback for ccw devices. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-07-15PM: Improve error code of pm_notifier_call_chain()Akinobu Mita1-4/+4
This enables pm_notifier_call_chain() to get the actual error code in the callback rather than always assume -EINVAL by converting all PM notifier calls to return encapsulate error code with notifier_from_errno(). Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-03-15[S390] css_bus_type: make it staticSebastian Ott1-2/+2
Make css_bus_type static. Subchannel drivers have to use css_driver_register. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-03-15[S390] css_driver: remove duplicate membersSebastian Ott1-2/+0
Remove the owner and name members of struct css_driver and convert all drivers to store this data in the embedded struct device_driver. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-01-05[S390] css: update subchannel descriptorSebastian Ott1-0/+8
Update the subchannel descriptor if we receive a "Installed parameters modified" crw. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-12-01[S390] css: fix rsid evaluation for 2nd crwSebastian Ott1-1/+1
Use correct bit positions of rsid field. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-10-25[S390] css: update subchannel description after hibernateSebastian Ott1-0/+1
Update the subchannel descriptor while resuming from hibernate in order to obtain current link addresses. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-10-25[S390] css: update descriptor after hibernateSebastian Ott1-0/+9
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>
2010-10-25[S390] chsc: consolidate memory allocationsSebastian Ott1-21/+3
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>
2010-10-25[S390] chsc: initialization fixesSebastian Ott1-9/+9
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>