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2016-07-06xen: xenbus: Remove create_workqueueBhaktipriya Shridhar1-14/+1
System workqueues have been able to handle high level of concurrency for a long time now and there's no reason to use dedicated workqueues just to gain concurrency. Replace dedicated xenbus_frontend_wq with the use of system_wq. Unlike a dedicated per-cpu workqueue created with create_workqueue(), system_wq allows multiple work items to overlap executions even on the same CPU; however, a per-cpu workqueue doesn't have any CPU locality or global ordering guarantees unless the target CPU is explicitly specified and the increase of local concurrency shouldn't make any difference. In this case, there is only a single work item, increase of concurrency level by switching to system_wq should not make any difference. Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-10-06xen: remove DEFINE_XENBUS_DRIVER() macroDavid Vrabel1-3/+5
The DEFINE_XENBUS_DRIVER() macro looks a bit weird and causes sparse errors. Replace the uses with standard structure definitions instead. This is similar to pci and usb device registration. Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-01-03xen/pvhvm: If xen_platform_pci=0 is set don't blow up (v4).Konrad Rzeszutek Wilk1-1/+1
The user has the option of disabling the platform driver: 00:02.0 Unassigned class [ff80]: XenSource, Inc. Xen Platform Device (rev 01) which is used to unplug the emulated drivers (IDE, Realtek 8169, etc) and allow the PV drivers to take over. If the user wishes to disable that they can set: xen_platform_pci=0 (in the guest config file) or xen_emul_unplug=never (on the Linux command line) except it does not work properly. The PV drivers still try to load and since the Xen platform driver is not run - and it has not initialized the grant tables, most of the PV drivers stumble upon: input: Xen Virtual Keyboard as /devices/virtual/input/input5 input: Xen Virtual Pointer as /devices/virtual/input/input6M ------------[ cut here ]------------ kernel BUG at /home/konrad/ssd/konrad/linux/drivers/xen/grant-table.c:1206! invalid opcode: 0000 [#1] SMP Modules linked in: xen_kbdfront(+) xenfs xen_privcmd CPU: 6 PID: 1389 Comm: modprobe Not tainted 3.13.0-rc1upstream-00021-ga6c892b-dirty #1 Hardware name: Xen HVM domU, BIOS 4.4-unstable 11/26/2013 RIP: 0010:[<ffffffff813ddc40>] [<ffffffff813ddc40>] get_free_entries+0x2e0/0x300 Call Trace: [<ffffffff8150d9a3>] ? evdev_connect+0x1e3/0x240 [<ffffffff813ddd0e>] gnttab_grant_foreign_access+0x2e/0x70 [<ffffffffa0010081>] xenkbd_connect_backend+0x41/0x290 [xen_kbdfront] [<ffffffffa0010a12>] xenkbd_probe+0x2f2/0x324 [xen_kbdfront] [<ffffffff813e5757>] xenbus_dev_probe+0x77/0x130 [<ffffffff813e7217>] xenbus_frontend_dev_probe+0x47/0x50 [<ffffffff8145e9a9>] driver_probe_device+0x89/0x230 [<ffffffff8145ebeb>] __driver_attach+0x9b/0xa0 [<ffffffff8145eb50>] ? driver_probe_device+0x230/0x230 [<ffffffff8145eb50>] ? driver_probe_device+0x230/0x230 [<ffffffff8145cf1c>] bus_for_each_dev+0x8c/0xb0 [<ffffffff8145e7d9>] driver_attach+0x19/0x20 [<ffffffff8145e260>] bus_add_driver+0x1a0/0x220 [<ffffffff8145f1ff>] driver_register+0x5f/0xf0 [<ffffffff813e55c5>] xenbus_register_driver_common+0x15/0x20 [<ffffffff813e76b3>] xenbus_register_frontend+0x23/0x40 [<ffffffffa0015000>] ? 0xffffffffa0014fff [<ffffffffa001502b>] xenkbd_init+0x2b/0x1000 [xen_kbdfront] [<ffffffff81002049>] do_one_initcall+0x49/0x170 .. snip.. which is hardly nice. This patch fixes this by having each PV driver check for: - if running in PV, then it is fine to execute (as that is their native environment). - if running in HVM, check if user wanted 'xen_emul_unplug=never', in which case bail out and don't load any PV drivers. - if running in HVM, and if PCI device 5853:0001 (xen_platform_pci) does not exist, then bail out and not load PV drivers. - (v2) if running in HVM, and if the user wanted 'xen_emul_unplug=ide-disks', then bail out for all PV devices _except_ the block one. Ditto for the network one ('nics'). - (v2) if running in HVM, and if the user wanted 'xen_emul_unplug=unnecessary' then load block PV driver, and also setup the legacy IDE paths. In (v3) make it actually load PV drivers. Reported-by: Sander Eikelenboom <linux@eikelenboom.it Reported-by: Anthony PERARD <anthony.perard@citrix.com> Reported-and-Tested-by: Fabio Fantoni <fabio.fantoni@m2r.biz> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [v2: Add extra logic to handle the myrid ways 'xen_emul_unplug' can be used per Ian and Stefano suggestion] [v3: Make the unnecessary case work properly] [v4: s/disks/ide-disks/ spotted by Fabio] Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> [for PCI parts] CC: stable@vger.kernel.org
2013-10-16xenbus: convert bus code to use dev_groupsGreg Kroah-Hartman1-1/+1
The dev_attrs field of struct bus_type is going away soon, dev_groups should be used instead. This converts the xenbus code to use the correct field. Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: <xen-devel@lists.xenproject.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-29xenbus: frontend resume cleanupAurelien Chartier1-3/+16
Only create the delayed resume workqueue if we are running in the same domain as xenstored and issue a warning if the workqueue creation fails. Move the work initialization to the device probe so it is done only once. Signed-off-by: Aurelien Chartier <aurelien.chartier@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2013-06-28xen: Convert printks to pr_<level>Joe Perches1-17/+18
Convert printks to pr_<level> (excludes printk(KERN_DEBUG...) to be more consistent throughout the xen subsystem. Add pr_fmt with KBUILD_MODNAME or "xen:" KBUILD_MODNAME Coalesce formats and add missing word spaces Add missing newlines Align arguments and reflow to 80 columns Remove DRV_NAME from formats as pr_fmt adds the same content This does change some of the prefixes of these messages but it also does make them more consistent. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-29xenbus: delay xenbus frontend resume if xenstored is not runningAurelien Chartier1-1/+36
If the xenbus frontend is located in a domain running xenstored, the device resume is hanging because it is happening before the process resume. This patch adds extra logic to the resume code to check if we are the domain running xenstored and delay the resume if needed. Signed-off-by: Aurelien Chartier <aurelien.chartier@citrix.com> [Changes in v2: - Instead of bypassing the resume, process it in a workqueue] [Changes in v3: - Add a struct work in xenbus_device to avoid dynamic allocation - Several small code fixes] [Changes in v4: - Use a dedicated workqueue] [Changes in v5: - Move create_workqueue error handling to xenbus_frontend_dev_resume] Acked-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-21xen: missing includesStefano Stabellini1-0/+1
Changes in v2: - remove pvclock hack; - remove include linux/types.h from xen/interface/xen.h. v3: - Compile under IA64 Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-19xen/xenbus: Add quirk to deal with misconfigured backends.Konrad Rzeszutek Wilk1-16/+53
A rather annoying and common case is when booting a PVonHVM guest and exposing the PV KBD and PV VFB - as broken toolstacks don't always initialize the backends correctly. Normally The HVM guest is using the VGA driver and the emulated keyboard for this (though upstream version of QEMU implements PV KBD, but still uses a VGA driver). We provide a very basic two-stage wait mechanism - where we wait for 30 seconds for all devices, and then for 270 for all them except the two mentioned. That allows us to wait for the essential devices, like network or disk for the full 6 minutes. To trigger this, put this in your guest config: vfb = [ 'vnc=1, vnclisten=0.0.0.0 ,vncunused=1'] instead of this: vnc=1 vnclisten="0.0.0.0" CC: stable@kernel.org Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> [v3: Split delay in non-essential (30 seconds) and essential devices per Ian and Stefano suggestion] [v4: Added comments per Stefano suggestion] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-13xen/xenbus: ignore console/0Stefano Stabellini1-0/+6
Unfortunately xend creates a bogus console/0 frotend/backend entry pair on xenstore that console backends cannot properly cope with. Any guest behavior that is not completely ignoring console/0 is going to either cause problems with xenconsoled or qemu. Returning 0 or -ENODEV from xencons_probe is not enough because it is going to cause the frontend state to become 4 or 6 respectively. The best possible thing we can do here is just ignore the entry from xenbus_probe_frontend. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-01-04Xen: consolidate and simplify struct xenbus_driver instantiationJan Beulich1-5/+3
The 'name', 'owner', and 'mod_name' members are redundant with the identically named fields in the 'driver' sub-structure. Rather than switching each instance to specify these fields explicitly, introduce a macro to simplify this. Eliminate further redundancy by allowing the drvname argument to DEFINE_XENBUS_DRIVER() to be blank (in which case the first entry from the ID table will be used for .driver.name). Also eliminate the questionable xenbus_register_{back,front}end() wrappers - their sole remaining purpose was the checking of the 'owner' field, proper setting of which shouldn't be an issue anymore when the macro gets used. v2: Restore DRV_NAME for the driver name in xen-pciback. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-31xen: Add module.h to modular drivers/xen users.Paul Gortmaker1-0/+1
Previously these drivers just got module.h implicitly, but we are cleaning that up and it will be no longer. Call out the real users of it. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-25Merge branches 'stable/drivers-3.2', 'stable/drivers.bugfixes-3.2' and ↵Linus Torvalds1-0/+121
'stable/pci.fixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen * 'stable/drivers-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xenbus: don't rely on xen_initial_domain to detect local xenstore xenbus: Fix loopback event channel assuming domain 0 xen/pv-on-hvm:kexec: Fix implicit declaration of function 'xen_hvm_domain' xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from old kernel xen/pv-on-hvm kexec: update xs_wire.h:xsd_sockmsg_type from xen-unstable xen/pv-on-hvm kexec+kdump: reset PV devices in kexec or crash kernel xen/pv-on-hvm kexec: rebind virqs to existing eventchannel ports xen/pv-on-hvm kexec: prevent crash in xenwatch_thread() when stale watch events arrive * 'stable/drivers.bugfixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/pciback: Check if the device is found instead of blindly assuming so. xen/pciback: Do not dereference psdev during printk when it is NULL. xen: remove XEN_PLATFORM_PCI config option xen: XEN_PVHVM depends on PCI xen/pciback: double lock typo xen/pciback: use mutex rather than spinlock in vpci backend xen/pciback: Use mutexes when working with Xenbus state transitions. xen/pciback: miscellaneous adjustments xen/pciback: use mutex rather than spinlock in passthrough backend xen/pciback: use resource_size() * 'stable/pci.fixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/pci: support multi-segment systems xen-swiotlb: When doing coherent alloc/dealloc check before swizzling the MFNs. xen/pci: make bus notifier handler return sane values xen-swiotlb: fix printk and panic args xen-swiotlb: Fix wrong panic. xen-swiotlb: Retry up three times to allocate Xen-SWIOTLB xen-pcifront: Update warning comment to use 'e820_host' option.
2011-09-01xen/pv-on-hvm kexec+kdump: reset PV devices in kexec or crash kernelOlaf Hering1-0/+121
After triggering a crash dump in a HVM guest, the PV backend drivers will remain in Connected state. When the kdump kernel starts the PV drivers will skip such devices. As a result, no root device is found and the vmcore cant be saved. A similar situation happens after a kexec boot, here the devices will be in the Closed state. With this change all frontend devices with state XenbusStateConnected or XenbusStateClosed will be reset by changing the state file to Closing -> Closed -> Initializing. This will trigger a disconnect in the backend drivers. Now the frontend drivers will find the backend drivers in state Initwait and can connect. Signed-off-by: Olaf Hering <olaf@aepfle.de> [v2: - add timeout when waiting for backend state change (based on feedback from Ian Campell) - extent printk message to include backend string - add comment to fall-through case in xenbus_reset_frontend] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-06-30xen: Populate xenbus device attributesBastian Blank1-5/+1
The xenbus bus type uses device_create_file to assign all used device attributes. However it does not remove them when the device goes away. This patch uses the dev_attrs field of the bus type to specify default attributes for all devices. Signed-off-by: Bastian Blank <waldi@debian.org> Acked-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-16xen: use freeze/restore/thaw PM events for suspend/resume/chkptShriram Rajagopalan1-3/+5
Use PM_FREEZE, PM_THAW and PM_RESTORE power events for suspend/resume/checkpoint functionality, instead of PM_SUSPEND and PM_RESUME. Use of these pm events fixes the Xen Guest hangup when taking checkpoints. When a suspend event is cancelled (while taking checkpoints once/continuously), we use PM_THAW instead of PM_RESUME. PM_RESTORE is used when suspend is not cancelled. See Documentation/power/devices.txt and linux/pm.h for more info about freeze, thaw and restore. The sequence of pm events in a suspend-resume scenario is shown below. dpm_suspend_start(PMSG_FREEZE); dpm_suspend_noirq(PMSG_FREEZE); sysdev_suspend(PMSG_FREEZE); cancelled = suspend_hypercall() sysdev_resume(); dpm_resume_noirq(cancelled ? PMSG_THAW : PMSG_RESTORE); dpm_resume_end(cancelled ? PMSG_THAW : PMSG_RESTORE); Acked-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-16xen: xenbus PM events supportKazuhiro SUZUKI1-2/+7
Make xenbus frontend device subscribe to PM events to receive suspend/resume/freeze/thaw/restore notifications. Signed-off-by: Kenji Wakamiya <wkenji@jp.fujitsu.com> Signed-off-by: Kazuhiro Suzuki <kaz@jp.fujitsu.com> Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca> Acked-by: Ian Campbell <ian.campbell@citrix.com> [shriram--minor mods and improved commit message] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05xen/xenbus: fixup checkpatch issues in xenbus_probe*Ian Campbell1-13/+15
Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05xen/xenbus: clean up noise in xenbus_probe_frontend.cJeremy Fitzhardinge1-7/+2
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ian Campbell <ian.campbell@citrix.com> [corresponds to 616ff7a06a3f in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05xen/xenbus: make frontend bus GPLJeremy Fitzhardinge1-0/+2
Make sure frontend xenbus has a GPL module license, so it can access all the xenbus symbols exported GPL only. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ian Campbell <ian.campbell@citrix.com> [corresponds to 525cbc8adcb5 in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05xenbus/frontend: register bus earlierJeremy Fitzhardinge1-2/+1
Impact: bugfix Make sure the frontend bus is registered early, before any drivers want to attach. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ian Campbell <ian.campbell@citrix.com> [corresponds to 1d5df318f87f in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05xen: add backend driver supportIan Campbell1-9/+30
Impact: backend device support Add the basic machinery to support backend drivers. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> [corresponds to 79727b851bac in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-01-05xen: separate out frontend xenbusIan Campbell1-0/+275
Impact: refactor Make a distinct frontend xenbus, in preparation for adding a backend xenbus. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> [corresponds to 2fd433a4188f in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git with adjustments to reflect changes in the code which is moved] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>