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* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 320Thomas Gleixner2019-06-051-14/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms and conditions of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 33 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190530000435.254582722@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Offload the handling of channels to two workqueuesDexuan Cui2018-12-031-3/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | vmbus_process_offer() mustn't call channel->sc_creation_callback() directly for sub-channels, because sc_creation_callback() -> vmbus_open() may never get the host's response to the OPEN_CHANNEL message (the host may rescind a channel at any time, e.g. in the case of hot removing a NIC), and vmbus_onoffer_rescind() may not wake up the vmbus_open() as it's blocked due to a non-zero vmbus_connection.offer_in_progress, and finally we have a deadlock. The above is also true for primary channels, if the related device drivers use sync probing mode by default. And, usually the handling of primary channels and sub-channels can depend on each other, so we should offload them to different workqueues to avoid possible deadlock, e.g. in sync-probing mode, NIC1's netvsc_subchan_work() can race with NIC2's netvsc_probe() -> rtnl_lock(), and causes deadlock: the former gets the rtnl_lock and waits for all the sub-channels to appear, but the latter can't get the rtnl_lock and this blocks the handling of sub-channels. The patch can fix the multiple-NIC deadlock described above for v3.x kernels (e.g. RHEL 7.x) which don't support async-probing of devices, and v4.4, v4.9, v4.14 and v4.18 which support async-probing but don't enable async-probing for Hyper-V drivers (yet). The patch can also fix the hang issue in sub-channel's handling described above for all versions of kernels, including v4.19 and v4.20-rc4. So actually the patch should be applied to all the existing kernels, not only the kernels that have 8195b1396ec8. Fixes: 8195b1396ec8 ("hv_netvsc: fix deadlock on hotplug") Cc: stable@vger.kernel.org Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Use get/put_cpu() in vmbus_connect()Dexuan Cui2018-09-301-3/+5
| | | | | | | | | | | | | | | | | | | | | | With CONFIG_DEBUG_PREEMPT=y, I always see this warning: BUG: using smp_processor_id() in preemptible [00000000] Fix the false warning by using get/put_cpu(). Here vmbus_connect() sends a message to the host and waits for the host's response. The host will deliver the response message and an interrupt on CPU msg->target_vcpu, and later the interrupt handler will wake up vmbus_connect(). vmbus_connect() doesn't really have to run on the same cpu as CPU msg->target_vcpu, so it's safe to call put_cpu() just here. Signed-off-by: Dexuan Cui <decui@microsoft.com> Cc: stable@vger.kernel.org Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Removed an unnecessary cast from void *Dexuan Cui2018-05-151-1/+1
| | | | | | | | | | In C, we don't need such a cast. Fixes: ae20b254306a ("Drivers: hv: vmbus: enable VMBus protocol version 5.0") Reported-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: Dexuan Cui <decui@microsoft.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: enable VMBus protocol version 5.0Dexuan Cui2018-05-141-2/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With VMBus protocol 5.0, we're able to better support new features, e.g. running two or more VMBus drivers simultaneously in a single VM -- note: we can't simply load the current VMBus driver twice, instead, a secondary VMBus driver must be implemented. This patch adds the support for the new VMBus protocol, which is available on new Windows hosts, by: 1) We still use SINT2 for compatibility; 2) We must use Connection ID 4 for the Initiate Contact Message, and for subsequent messages, we must use the Message Connection ID field in the host-returned VersionResponse Message. Notes for developers of the secondary VMBus driver: 1) Must use VMBus protocol 5.0 as well; 2) Must use a different SINT number that is not in use. 3) Must use Connection ID 4 for the Initiate Contact Message, and for subsequent messages, must use the Message Connection ID field in the host-returned VersionResponse Message. 4) It's possible that the primary VMBus driver using protocol version 4.0 can work with a secondary VMBus driver using protocol version 5.0, but it's recommended that both should use 5.0 for new Hyper-V features in the future. Signed-off-by: Dexuan Cui <decui@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Michael Kelley <mikelley@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86/hyper-v: move hyperv.h out of uapiVitaly Kuznetsov2018-03-281-1/+0
| | | | | | | | | | | | | | | | hyperv.h is not part of uapi, there are no (known) users outside of kernel. We are making changes to this file to match current Hyper-V Hypervisor Top-Level Functional Specification (TLFS, see: https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/reference/tlfs) and we don't want to maintain backwards compatibility. Move the file renaming to hyperv-tlfs.h to avoid confusing it with mshyperv.h. In future, all definitions from TLFS should go to it and all kernel objects should go to mshyperv.h or include/linux/hyperv.h. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
* hyper-v: trace channel eventsVitaly Kuznetsov2017-11-041-0/+2
| | | | | | | | | | Added an additional set of trace points for when channel gets notified or signals host. Suggested-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* hyper-v: trace vmbus_negotiate_version()Vitaly Kuznetsov2017-11-041-0/+3
| | | | | | | | Add tracepoint to CHANNELMSG_INITIATE_CONTACT sender. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Expose per-channel interrupts and events countersStephen Hemminger2017-10-311-0/+2
| | | | | | | | | | When investigating performance, it is useful to be able to look at the number of host and guest events per-channel. This is equivalent to per-device interrupt statistics. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* hyper-v: Globalize vp_indexVitaly Kuznetsov2017-08-101-1/+2
| | | | | | | | | | | | | | | | | | | | | | To support implementing remote TLB flushing on Hyper-V with a hypercall we need to make vp_index available outside of vmbus module. Rename and globalize. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Stephen Hemminger <sthemmin@microsoft.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Jork Loeser <Jork.Loeser@microsoft.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Simon Xiao <sixiao@microsoft.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: devel@linuxdriverproject.org Link: http://lkml.kernel.org/r/20170802160921.21791-7-vkuznets@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* hyper-v: Use fast hypercall for HVCALL_SIGNAL_EVENTVitaly Kuznetsov2017-08-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | We need to pass only 8 bytes of input for HvSignalEvent which makes it a perfect fit for fast hypercall. hv_input_signal_event_buffer is not needed any more and hv_input_signal_event is converted to union for convenience. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Stephen Hemminger <sthemmin@microsoft.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Jork Loeser <Jork.Loeser@microsoft.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Simon Xiao <sixiao@microsoft.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: devel@linuxdriverproject.org Link: http://lkml.kernel.org/r/20170802160921.21791-5-vkuznets@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/hyper-v: Make hv_do_hypercall() inlineVitaly Kuznetsov2017-08-101-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | We have only three call sites for hv_do_hypercall() and we're going to change HVCALL_SIGNAL_EVENT to doing fast hypercall so we can inline this function for optimization. Hyper-V top level functional specification states that r9-r11 registers and flags may be clobbered by the hypervisor during hypercall and with inlining this is somewhat important, add the clobbers. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Stephen Hemminger <sthemmin@microsoft.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Jork Loeser <Jork.Loeser@microsoft.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Simon Xiao <sixiao@microsoft.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: devel@linuxdriverproject.org Link: http://lkml.kernel.org/r/20170802160921.21791-3-vkuznets@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* drivers: hv: vmbus: Increase the time between retries in vmbus_post_msg()K. Y. Srinivasan2017-05-251-1/+1
| | | | | | | | | | | Commit c0bb03924f1a ("Drivers: hv: vmbus: Raise retry/wait limits in vmbus_post_msg()") increased the retry/wait limits of vmbus_post_msg() to address the new DoS protection policies in WS2016. Increase the time between retries to make the code more robust. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Fix rescind handlingK. Y. Srinivasan2017-05-181-2/+5
| | | | | | | | | | | | | | | | Fix the rescind handling. This patch addresses the following rescind scenario that is currently not handled correctly: If a rescind were to be received while the offer is still being peocessed, we will be blocked indefinitely since the rescind message is handled on the same work element as the offer message. Fix this issue. I would like to thank Dexuan Cui <decui@microsoft.com> and Long Li <longli@microsoft.com> for working with me on this patch. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Fix error code returned by vmbus_post_msg()K. Y. Srinivasan2017-05-181-1/+1
| | | | | | | | | ENOBUFS is a more approrpiate error code to be returned when the hypervisor cannot post the message because of insufficient buffers. Make the adjustment. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* vmbus: only reschedule tasklet if time limit exceededStephen Hemminger2017-03-171-31/+34
| | | | | | | | | | | | | | | The change to reschedule tasklet if more data arrives in ring buffer can cause performance regression if host timing is such that the next response happens in small window. Go back to a modified version of the original looping behavior. If the race occurs in a small time, then loop. But if the tasklet has been running for a long interval due to flood, then reschedule the tasklet to allow migration to ksoftirqd. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* vmbus: add direct isr callback modeStephen Hemminger2017-02-141-15/+12
| | | | | | | | | | | | | | Change the simple boolean batched_reading into a tri-value. For future NAPI support in netvsc driver, the callback needs to occur directly in interrupt handler. Batched mode is also changed to disable host interrupts immediately in interrupt routine (to avoid unnecessary host signals), and the tasklet is rescheduled if more data is detected. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* vmbus: change to per channel taskletStephen Hemminger2017-02-141-75/+3
| | | | | | | | | | Make the event handling tasklet per channel rather than per-cpu. This allows for better fairness when getting lots of data on the same cpu. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* vmbus: put related per-cpu variable togetherStephen Hemminger2017-02-141-11/+9
| | | | | | | | | | The hv_context structure had several arrays which were per-cpu and was allocating small structures (tasklet_struct). Instead use a single per-cpu array. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* vmbus: use kernel bitops for traversing interrupt maskStephen Hemminger2017-02-101-38/+17
| | | | | | | | | | Use standard kernel operations for find first set bit to traverse the channel bit array. This has added benefit of speeding up lookup on 64 bit and because it uses find first set instruction. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Move the extracting of Hypervisor version informationK. Y. Srinivasan2017-01-201-5/+2
| | | | | | | | | As part of the effort to separate out architecture specific code, extract hypervisor version information in an architecture specific file. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Raise retry/wait limits in vmbus_post_msg()Vitaly Kuznetsov2017-01-101-5/+12
| | | | | | | | | | | | | | | | | | | | | | DoS protection conditions were altered in WS2016 and now it's easy to get -EAGAIN returned from vmbus_post_msg() (e.g. when we try changing MTU on a netvsc device in a loop). All vmbus_post_msg() callers don't retry the operation and we usually end up with a non-functional device or crash. While host's DoS protection conditions are unknown to me my tests show that it can take up to 10 seconds before the message is sent so doing udelay() is not an option, we really need to sleep. Almost all vmbus_post_msg() callers are ready to sleep but there is one special case: vmbus_initiate_unload() which can be called from interrupt/NMI context and we can't sleep there. I'm also not sure about the lonely vmbus_send_tl_connect_request() which has no in-tree users but its external users are most likely waiting for the host to reply so sleeping there is also appropriate. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* uio-hv-generic: new userspace i/o driver for VMBusStephen Hemminger2016-12-061-0/+1
| | | | | | | | | | This is a new driver to enable userspace networking on VMBus. It is based largely on the similar driver that already exists for PCI, and earlier work done by Brocade to support DPDK. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Reduce the delay between retries in vmbus_post_msg()K. Y. Srinivasan2016-08-311-4/+4
| | | | | | | | The current delay between retries is unnecessarily high and is negatively affecting the time it takes to boot the system. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Export the vmbus_set_event() APIK. Y. Srinivasan2016-04-301-0/+1
| | | | | | | | In preparation for moving some ring buffer functionality out of the vmbus driver, export the API for signaling the host. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Support kexec on ws2012 r2 and aboveAlex Ng2016-03-011-1/+9
| | | | | | | | | | | WS2012 R2 and above hosts can support kexec in that thay can support reconnecting to the host (as would be needed in the kexec path) on any CPU. Enable this. Pre ws2012 r2 hosts don't have this ability and consequently cannot support kexec. Signed-off-by: Alex Ng <alexng@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: avoid wait_for_completion() on crashVitaly Kuznetsov2016-03-011-1/+1
| | | | | | | | | | | | | wait_for_completion() may sleep, it enables interrupts and this is something we really want to avoid on crashes because interrupt handlers can cause other crashes. Switch to the recently introduced vmbus_wait_for_unload() doing busy wait instead. Reported-by: Radim Krcmar <rkrcmar@redhat.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Radim Kr.má<rkrcmar@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: add an API vmbus_hvsock_device_unregister()Dexuan Cui2016-02-071-2/+2
| | | | | | | | | The hvsock driver needs this API to release all the resources related to the channel. Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Cleanup vmbus_set_event()K. Y. Srinivasan2016-02-071-2/+2
| | | | | | | | | | Cleanup vmbus_set_event() by inlining the hypercall to post the event and since the return value of vmbus_set_event() is not checked, make it void. As part of this cleanup, get rid of the function hv_signal_event() as it is only callled from vmbus_set_event(). Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Force all channel messages to be delivered on CPU 0K. Y. Srinivasan2015-12-141-4/+7
| | | | | | | | | Force all channel messages to be delivered on CPU0. These messages are not performance critical and are used during the setup and teardown of the channel. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: channge vmbus_connection.channel_lock to mutexDexuan Cui2015-12-141-4/+3
| | | | | | | | | spinlock is unnecessary here. mutex is enough. Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus:Update preferred vmbus protocol version to windows 10.Keith Mange2015-06-011-3/+5
| | | | | | | | Add support for Windows 10. Signed-off-by: Keith Mange <keith.mange@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Implement the protocol for tearing down vmbus stateK. Y. Srinivasan2015-05-241-0/+5
| | | | | | | | | Implement the protocol for tearing down the monitor state established with the host. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* hv_vmbus: Add gradually increased delay for retries in vmbus_post_msg()Haiyang Zhang2015-04-031-2/+5
| | | | | | | | | | | | | Most of the retries can be done within a millisecond successfully, so we sleep 1ms before the first retry, then gradually increase the retry interval to 2^n with max value of 2048ms. Doing so, we will have shorter overall delay time, because most of the cases succeed within 1-2 attempts. Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com> Reviewed-by: K. Y. Srinivasan <kys@microsoft.com> Reviewed-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* hv: don't schedule new works in vmbus_onoffer()/vmbus_onoffer_rescind()Dexuan Cui2015-04-031-5/+1
| | | | | | | | | | | | | Since the 2 fucntions can safely run in vmbus_connection.work_queue without hang, we don't need to schedule new work items into the per-channel workqueue. Actally we can even remove the per-channel workqueue now -- we'll do it in the next patch. Signed-off-by: Dexuan Cui <decui@microsoft.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Perform device register in the per-channel work elementK. Y. Srinivasan2015-03-251-1/+5
| | | | | | | | | | | | | This patch is a continuation of the rescind handling cleanup work. We cannot block in the global message handling work context especially if we are blocking waiting for the host to wake us up. I would like to thank Dexuan Cui <decui@microsoft.com> for observing this problem. The current char-next branch is broken and this patch fixes the bug. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Get rid of some unnecessary messagesK. Y. Srinivasan2015-03-011-6/+1
| | | | | | | | | | Currently we log messages when either we are not able to map an ID to a channel or when the channel does not have a callback associated (in the channel interrupt handling path). These messages don't add any value, get rid of them. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* hv: vmbus_post_msg: retry the hypercall on some transient errorsDexuan Cui2015-03-011-2/+9
| | | | | | | | | | | | | | | | | | | I got HV_STATUS_INVALID_CONNECTION_ID on Hyper-V 2008 R2 when keeping running "rmmod hv_netvsc; modprobe hv_netvsc; rmmod hv_utils; modprobe hv_utils" in a Linux guest. Looks the host has some kind of throttling mechanism if some kinds of hypercalls are sent too frequently. Without the patch, the driver can occasionally fail to load. Also let's retry HV_STATUS_INSUFFICIENT_MEMORY, though we didn't get it before. Removed 'case -ENOMEM', since the hypervisor doesn't return this. CC: "K. Y. Srinivasan" <kys@microsoft.com> Reviewed-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: teardown hv_vmbus_con workqueue and vmbus_connection ↵Vitaly Kuznetsov2015-03-011-5/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pages on shutdown We need to destroy hv_vmbus_con on module shutdown, otherwise the following crash is sometimes observed: [ 76.569845] hv_vmbus: Hyper-V Host Build:9600-6.3-17-0.17039; Vmbus version:3.0 [ 82.598859] BUG: unable to handle kernel paging request at ffffffffa0003480 [ 82.599287] IP: [<ffffffffa0003480>] 0xffffffffa0003480 [ 82.599287] PGD 1f34067 PUD 1f35063 PMD 3f72d067 PTE 0 [ 82.599287] Oops: 0010 [#1] SMP [ 82.599287] Modules linked in: [last unloaded: hv_vmbus] [ 82.599287] CPU: 0 PID: 26 Comm: kworker/0:1 Not tainted 3.19.0-rc5_bug923184+ #488 [ 82.599287] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v1.0 11/26/2012 [ 82.599287] Workqueue: hv_vmbus_con 0xffffffffa0003480 [ 82.599287] task: ffff88007b6ddfa0 ti: ffff88007f8f8000 task.ti: ffff88007f8f8000 [ 82.599287] RIP: 0010:[<ffffffffa0003480>] [<ffffffffa0003480>] 0xffffffffa0003480 [ 82.599287] RSP: 0018:ffff88007f8fbe00 EFLAGS: 00010202 ... To avoid memory leaks we need to free monitor_pages and int_page for vmbus_connection. Implement vmbus_disconnect() function by separating cleanup path from vmbus_connect(). As we use hv_vmbus_con to release channels (see free_channel() in channel_mgmt.c) we need to make sure the work was done before we remove the queue, do that with drain_workqueue(). We also need to avoid handling messages which can (potentially) create new channels, so set vmbus_connection.conn_state = DISCONNECTED at the very beginning of vmbus_exit() and check for that in vmbus_onmessage_work(). Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Use get_cpu() to get the current CPUK. Y. Srinivasan2015-01-121-2/+4
| | | | | | | | | Replace calls for smp_processor_id() to get_cpu() to get the CPU ID of the current CPU. In these instances, there is no correctness issue with regards to preemption, we just need the current CPU ID. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Cleanup vmbus_post_msg()K. Y. Srinivasan2014-09-231-3/+14
| | | | | | | | | | | | | | Posting messages to the host can fail because of transient resource related failures. Correctly deal with these failures and increase the number of attempts to post the message before giving up. In this version of the patch, I have normalized the error code to Linux error code. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: <stable@vger.kernel.org> Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Fix a bug in the channel callback dispatch codeK. Y. Srinivasan2014-07-091-2/+6
| | | | | | | | | | | | | Starting with Win8, we have implemented several optimizations to improve the scalability and performance of the VMBUS transport between the Host and the Guest. Some of the non-performance critical services cannot leverage these optimization since they only read and process one message at a time. Make adjustments to the callback dispatch code to account for the way non-performance critical drivers handle reading of the channel. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* hv: use correct order when freeing monitor_pagesRadim Krčmář2014-05-281-2/+2
| | | | | | | | | | | | We try to free two pages when only one has been allocated. Cleanup path is unlikely, so I haven't found any trace that would fit, but I hope that free_pages_prepare() does catch it. Cc: stable@vger.kernel.org Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Reviewed-by: Amos Kong <akong@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Implement per-CPU mapping of relid to channelK. Y. Srinivasan2014-05-031-1/+23
| | | | | | | | | | | Currently the mapping of the relID to channel is done under the protection of a single spin lock. Starting with ws2012, each channel is bound to a specific VCPU in the guest. Use this binding to eliminate the spin lock by setting up per-cpu state for mapping relId to the channel. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: Eliminate the channel spinlock in the callback pathK. Y. Srinivasan2014-05-031-7/+4
| | | | | | | | | | By ensuring that we set the callback handler to NULL in the channel close path on the same CPU that the channel is bound to, we can eliminate this lock acquisition and release in a performance critical path. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Negotiate version 3.0 when running on ws2012r2 hostsK. Y. Srinivasan2014-04-161-1/+4
| | | | | | | | | | Only ws2012r2 hosts support the ability to reconnect to the host on VMBUS. This functionality is needed by kexec in Linux. To use this functionality we need to negotiate version 3.0 of the VMBUS protocol. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: <stable@vger.kernel.org> [3.9+] Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Don't timeout during the initial connection with hostK. Y. Srinivasan2014-02-071-10/+1
| | | | | | | | | | | | | | | | When the guest attempts to connect with the host when there may already be a connection with the host (as would be the case during the kdump/kexec path), it is difficult to guarantee timely response from the host. Starting with WS2012 R2, the host supports this ability to re-connect with the host (explicitly to support kexec). Prior to responding to the guest, the host needs to ensure that device states based on the previous connection to the host have been properly torn down. This may introduce unbounded delays. To deal with this issue, don't do a timed wait during the initial connect with the host. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Drivers: hv: vmbus: Specify the target CPU that should receive notificationK. Y. Srinivasan2014-02-071-0/+2
| | | | | | | | | | | During the initial VMBUS connect phase, starting with WS2012 R2, we should specify the VPCU in the guest that should receive the notification. Fix this issue. This fix is required to properly connect to the host in the kexeced kernel. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: <stable@vger.kernel.org> [3.9+] Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge 3.12-rc3 into char-misc-nextGreg Kroah-Hartman2013-09-291-1/+1
|\ | | | | | | | | | | | | We need/want the mei fixes in here so we can apply other updates that are depending on them. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * Drivers: hv: vmbus: Terminate vmbus version negotiation on timeoutK. Y. Srinivasan2013-09-261-1/+1
| | | | | | | | | | | | | | | | | | | | commit 666b9adc801ef012612c4e43e0f44b2cdc1979cf terminated vmbus version negotiation incorrectly. We need to terminate the version negotiation only if the current negotiation were to timeout. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: Olaf Hering <ohering@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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