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![Alex Williamson](/assets/img/avatar_default.png)
The kernel no longer allows us to pass NULL for the hard handler without also specifying IRQF_ONESHOT. IRQF_ONESHOT imposes latency in the exit path that we don't need for MSI interrupts. Long term we'd like to inject these interrupts from the hard handler when possible. In the short term, we can create dummy hard handlers that return us to the previous behavior. Credit to Michael for original patch. Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=43328 Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
1036 lines
25 KiB
C
1036 lines
25 KiB
C
/*
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* Kernel-based Virtual Machine - device assignment support
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*
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* Copyright (C) 2010 Red Hat, Inc. and/or its affiliates.
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*
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* This work is licensed under the terms of the GNU GPL, version 2. See
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* the COPYING file in the top-level directory.
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*
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*/
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#include <linux/kvm_host.h>
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#include <linux/kvm.h>
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#include <linux/uaccess.h>
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#include <linux/vmalloc.h>
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#include <linux/errno.h>
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#include <linux/spinlock.h>
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#include <linux/pci.h>
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#include <linux/interrupt.h>
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#include <linux/slab.h>
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#include <linux/namei.h>
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#include <linux/fs.h>
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#include "irq.h"
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static struct kvm_assigned_dev_kernel *kvm_find_assigned_dev(struct list_head *head,
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int assigned_dev_id)
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{
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struct list_head *ptr;
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struct kvm_assigned_dev_kernel *match;
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list_for_each(ptr, head) {
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match = list_entry(ptr, struct kvm_assigned_dev_kernel, list);
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if (match->assigned_dev_id == assigned_dev_id)
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return match;
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}
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return NULL;
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}
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static int find_index_from_host_irq(struct kvm_assigned_dev_kernel
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*assigned_dev, int irq)
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{
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int i, index;
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struct msix_entry *host_msix_entries;
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host_msix_entries = assigned_dev->host_msix_entries;
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index = -1;
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for (i = 0; i < assigned_dev->entries_nr; i++)
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if (irq == host_msix_entries[i].vector) {
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index = i;
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break;
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}
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if (index < 0)
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printk(KERN_WARNING "Fail to find correlated MSI-X entry!\n");
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return index;
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}
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static irqreturn_t kvm_assigned_dev_intx(int irq, void *dev_id)
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{
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struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
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int ret;
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spin_lock(&assigned_dev->intx_lock);
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if (pci_check_and_mask_intx(assigned_dev->dev)) {
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assigned_dev->host_irq_disabled = true;
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ret = IRQ_WAKE_THREAD;
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} else
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ret = IRQ_NONE;
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spin_unlock(&assigned_dev->intx_lock);
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return ret;
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}
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static void
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kvm_assigned_dev_raise_guest_irq(struct kvm_assigned_dev_kernel *assigned_dev,
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int vector)
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{
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if (unlikely(assigned_dev->irq_requested_type &
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KVM_DEV_IRQ_GUEST_INTX)) {
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spin_lock(&assigned_dev->intx_mask_lock);
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if (!(assigned_dev->flags & KVM_DEV_ASSIGN_MASK_INTX))
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kvm_set_irq(assigned_dev->kvm,
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assigned_dev->irq_source_id, vector, 1);
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spin_unlock(&assigned_dev->intx_mask_lock);
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} else
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kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id,
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vector, 1);
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}
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static irqreturn_t kvm_assigned_dev_thread_intx(int irq, void *dev_id)
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{
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struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
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if (!(assigned_dev->flags & KVM_DEV_ASSIGN_PCI_2_3)) {
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spin_lock_irq(&assigned_dev->intx_lock);
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disable_irq_nosync(irq);
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assigned_dev->host_irq_disabled = true;
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spin_unlock_irq(&assigned_dev->intx_lock);
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}
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kvm_assigned_dev_raise_guest_irq(assigned_dev,
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assigned_dev->guest_irq);
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return IRQ_HANDLED;
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}
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#ifdef __KVM_HAVE_MSI
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static irqreturn_t kvm_assigned_dev_thread_msi(int irq, void *dev_id)
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{
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struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
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kvm_assigned_dev_raise_guest_irq(assigned_dev,
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assigned_dev->guest_irq);
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return IRQ_HANDLED;
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}
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#endif
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#ifdef __KVM_HAVE_MSIX
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static irqreturn_t kvm_assigned_dev_thread_msix(int irq, void *dev_id)
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{
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struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
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int index = find_index_from_host_irq(assigned_dev, irq);
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u32 vector;
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if (index >= 0) {
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vector = assigned_dev->guest_msix_entries[index].vector;
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kvm_assigned_dev_raise_guest_irq(assigned_dev, vector);
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}
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return IRQ_HANDLED;
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}
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#endif
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/* Ack the irq line for an assigned device */
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static void kvm_assigned_dev_ack_irq(struct kvm_irq_ack_notifier *kian)
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{
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struct kvm_assigned_dev_kernel *dev =
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container_of(kian, struct kvm_assigned_dev_kernel,
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ack_notifier);
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kvm_set_irq(dev->kvm, dev->irq_source_id, dev->guest_irq, 0);
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spin_lock(&dev->intx_mask_lock);
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if (!(dev->flags & KVM_DEV_ASSIGN_MASK_INTX)) {
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bool reassert = false;
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spin_lock_irq(&dev->intx_lock);
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/*
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* The guest IRQ may be shared so this ack can come from an
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* IRQ for another guest device.
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*/
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if (dev->host_irq_disabled) {
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if (!(dev->flags & KVM_DEV_ASSIGN_PCI_2_3))
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enable_irq(dev->host_irq);
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else if (!pci_check_and_unmask_intx(dev->dev))
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reassert = true;
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dev->host_irq_disabled = reassert;
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}
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spin_unlock_irq(&dev->intx_lock);
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if (reassert)
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kvm_set_irq(dev->kvm, dev->irq_source_id,
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dev->guest_irq, 1);
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}
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spin_unlock(&dev->intx_mask_lock);
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}
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static void deassign_guest_irq(struct kvm *kvm,
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struct kvm_assigned_dev_kernel *assigned_dev)
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{
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if (assigned_dev->ack_notifier.gsi != -1)
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kvm_unregister_irq_ack_notifier(kvm,
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&assigned_dev->ack_notifier);
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kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id,
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assigned_dev->guest_irq, 0);
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if (assigned_dev->irq_source_id != -1)
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kvm_free_irq_source_id(kvm, assigned_dev->irq_source_id);
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assigned_dev->irq_source_id = -1;
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assigned_dev->irq_requested_type &= ~(KVM_DEV_IRQ_GUEST_MASK);
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}
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/* The function implicit hold kvm->lock mutex due to cancel_work_sync() */
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static void deassign_host_irq(struct kvm *kvm,
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struct kvm_assigned_dev_kernel *assigned_dev)
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{
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/*
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* We disable irq here to prevent further events.
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*
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* Notice this maybe result in nested disable if the interrupt type is
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* INTx, but it's OK for we are going to free it.
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*
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* If this function is a part of VM destroy, please ensure that till
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* now, the kvm state is still legal for probably we also have to wait
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* on a currently running IRQ handler.
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*/
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if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSIX) {
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int i;
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for (i = 0; i < assigned_dev->entries_nr; i++)
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disable_irq(assigned_dev->host_msix_entries[i].vector);
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for (i = 0; i < assigned_dev->entries_nr; i++)
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free_irq(assigned_dev->host_msix_entries[i].vector,
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assigned_dev);
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assigned_dev->entries_nr = 0;
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kfree(assigned_dev->host_msix_entries);
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kfree(assigned_dev->guest_msix_entries);
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pci_disable_msix(assigned_dev->dev);
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} else {
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/* Deal with MSI and INTx */
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if ((assigned_dev->irq_requested_type &
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KVM_DEV_IRQ_HOST_INTX) &&
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(assigned_dev->flags & KVM_DEV_ASSIGN_PCI_2_3)) {
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spin_lock_irq(&assigned_dev->intx_lock);
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pci_intx(assigned_dev->dev, false);
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spin_unlock_irq(&assigned_dev->intx_lock);
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synchronize_irq(assigned_dev->host_irq);
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} else
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disable_irq(assigned_dev->host_irq);
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free_irq(assigned_dev->host_irq, assigned_dev);
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if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSI)
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pci_disable_msi(assigned_dev->dev);
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}
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assigned_dev->irq_requested_type &= ~(KVM_DEV_IRQ_HOST_MASK);
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}
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static int kvm_deassign_irq(struct kvm *kvm,
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struct kvm_assigned_dev_kernel *assigned_dev,
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unsigned long irq_requested_type)
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{
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unsigned long guest_irq_type, host_irq_type;
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if (!irqchip_in_kernel(kvm))
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return -EINVAL;
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/* no irq assignment to deassign */
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if (!assigned_dev->irq_requested_type)
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return -ENXIO;
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host_irq_type = irq_requested_type & KVM_DEV_IRQ_HOST_MASK;
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guest_irq_type = irq_requested_type & KVM_DEV_IRQ_GUEST_MASK;
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if (host_irq_type)
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deassign_host_irq(kvm, assigned_dev);
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if (guest_irq_type)
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deassign_guest_irq(kvm, assigned_dev);
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return 0;
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}
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static void kvm_free_assigned_irq(struct kvm *kvm,
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struct kvm_assigned_dev_kernel *assigned_dev)
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{
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kvm_deassign_irq(kvm, assigned_dev, assigned_dev->irq_requested_type);
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}
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static void kvm_free_assigned_device(struct kvm *kvm,
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struct kvm_assigned_dev_kernel
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*assigned_dev)
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{
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kvm_free_assigned_irq(kvm, assigned_dev);
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pci_reset_function(assigned_dev->dev);
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if (pci_load_and_free_saved_state(assigned_dev->dev,
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&assigned_dev->pci_saved_state))
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printk(KERN_INFO "%s: Couldn't reload %s saved state\n",
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__func__, dev_name(&assigned_dev->dev->dev));
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else
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pci_restore_state(assigned_dev->dev);
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assigned_dev->dev->dev_flags &= ~PCI_DEV_FLAGS_ASSIGNED;
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pci_release_regions(assigned_dev->dev);
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pci_disable_device(assigned_dev->dev);
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pci_dev_put(assigned_dev->dev);
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list_del(&assigned_dev->list);
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kfree(assigned_dev);
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}
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void kvm_free_all_assigned_devices(struct kvm *kvm)
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{
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struct list_head *ptr, *ptr2;
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struct kvm_assigned_dev_kernel *assigned_dev;
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list_for_each_safe(ptr, ptr2, &kvm->arch.assigned_dev_head) {
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assigned_dev = list_entry(ptr,
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struct kvm_assigned_dev_kernel,
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list);
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kvm_free_assigned_device(kvm, assigned_dev);
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}
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}
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static int assigned_device_enable_host_intx(struct kvm *kvm,
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struct kvm_assigned_dev_kernel *dev)
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{
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irq_handler_t irq_handler;
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unsigned long flags;
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dev->host_irq = dev->dev->irq;
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/*
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* We can only share the IRQ line with other host devices if we are
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* able to disable the IRQ source at device-level - independently of
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* the guest driver. Otherwise host devices may suffer from unbounded
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* IRQ latencies when the guest keeps the line asserted.
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*/
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if (dev->flags & KVM_DEV_ASSIGN_PCI_2_3) {
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irq_handler = kvm_assigned_dev_intx;
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flags = IRQF_SHARED;
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} else {
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irq_handler = NULL;
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flags = IRQF_ONESHOT;
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}
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if (request_threaded_irq(dev->host_irq, irq_handler,
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kvm_assigned_dev_thread_intx, flags,
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dev->irq_name, dev))
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return -EIO;
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if (dev->flags & KVM_DEV_ASSIGN_PCI_2_3) {
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spin_lock_irq(&dev->intx_lock);
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pci_intx(dev->dev, true);
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spin_unlock_irq(&dev->intx_lock);
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}
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return 0;
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}
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#ifdef __KVM_HAVE_MSI
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static irqreturn_t kvm_assigned_dev_msi(int irq, void *dev_id)
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{
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return IRQ_WAKE_THREAD;
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}
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static int assigned_device_enable_host_msi(struct kvm *kvm,
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struct kvm_assigned_dev_kernel *dev)
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{
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int r;
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if (!dev->dev->msi_enabled) {
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r = pci_enable_msi(dev->dev);
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if (r)
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return r;
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}
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dev->host_irq = dev->dev->irq;
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if (request_threaded_irq(dev->host_irq, kvm_assigned_dev_msi,
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kvm_assigned_dev_thread_msi, 0,
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dev->irq_name, dev)) {
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pci_disable_msi(dev->dev);
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return -EIO;
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}
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return 0;
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}
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#endif
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#ifdef __KVM_HAVE_MSIX
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static irqreturn_t kvm_assigned_dev_msix(int irq, void *dev_id)
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{
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return IRQ_WAKE_THREAD;
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}
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static int assigned_device_enable_host_msix(struct kvm *kvm,
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struct kvm_assigned_dev_kernel *dev)
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{
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int i, r = -EINVAL;
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/* host_msix_entries and guest_msix_entries should have been
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* initialized */
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if (dev->entries_nr == 0)
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return r;
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r = pci_enable_msix(dev->dev, dev->host_msix_entries, dev->entries_nr);
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if (r)
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return r;
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for (i = 0; i < dev->entries_nr; i++) {
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r = request_threaded_irq(dev->host_msix_entries[i].vector,
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kvm_assigned_dev_msix,
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kvm_assigned_dev_thread_msix,
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0, dev->irq_name, dev);
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if (r)
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goto err;
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}
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return 0;
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err:
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for (i -= 1; i >= 0; i--)
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free_irq(dev->host_msix_entries[i].vector, dev);
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pci_disable_msix(dev->dev);
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return r;
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}
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#endif
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static int assigned_device_enable_guest_intx(struct kvm *kvm,
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struct kvm_assigned_dev_kernel *dev,
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struct kvm_assigned_irq *irq)
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{
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dev->guest_irq = irq->guest_irq;
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dev->ack_notifier.gsi = irq->guest_irq;
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return 0;
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}
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#ifdef __KVM_HAVE_MSI
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static int assigned_device_enable_guest_msi(struct kvm *kvm,
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struct kvm_assigned_dev_kernel *dev,
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struct kvm_assigned_irq *irq)
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{
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dev->guest_irq = irq->guest_irq;
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dev->ack_notifier.gsi = -1;
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return 0;
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}
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#endif
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#ifdef __KVM_HAVE_MSIX
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static int assigned_device_enable_guest_msix(struct kvm *kvm,
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struct kvm_assigned_dev_kernel *dev,
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struct kvm_assigned_irq *irq)
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{
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dev->guest_irq = irq->guest_irq;
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dev->ack_notifier.gsi = -1;
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return 0;
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}
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#endif
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|
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static int assign_host_irq(struct kvm *kvm,
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struct kvm_assigned_dev_kernel *dev,
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__u32 host_irq_type)
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{
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int r = -EEXIST;
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if (dev->irq_requested_type & KVM_DEV_IRQ_HOST_MASK)
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return r;
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snprintf(dev->irq_name, sizeof(dev->irq_name), "kvm:%s",
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pci_name(dev->dev));
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switch (host_irq_type) {
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case KVM_DEV_IRQ_HOST_INTX:
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r = assigned_device_enable_host_intx(kvm, dev);
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break;
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#ifdef __KVM_HAVE_MSI
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case KVM_DEV_IRQ_HOST_MSI:
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r = assigned_device_enable_host_msi(kvm, dev);
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break;
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#endif
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#ifdef __KVM_HAVE_MSIX
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case KVM_DEV_IRQ_HOST_MSIX:
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r = assigned_device_enable_host_msix(kvm, dev);
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break;
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#endif
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default:
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r = -EINVAL;
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}
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dev->host_irq_disabled = false;
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if (!r)
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dev->irq_requested_type |= host_irq_type;
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return r;
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}
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|
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static int assign_guest_irq(struct kvm *kvm,
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struct kvm_assigned_dev_kernel *dev,
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struct kvm_assigned_irq *irq,
|
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unsigned long guest_irq_type)
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|
{
|
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int id;
|
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int r = -EEXIST;
|
|
|
|
if (dev->irq_requested_type & KVM_DEV_IRQ_GUEST_MASK)
|
|
return r;
|
|
|
|
id = kvm_request_irq_source_id(kvm);
|
|
if (id < 0)
|
|
return id;
|
|
|
|
dev->irq_source_id = id;
|
|
|
|
switch (guest_irq_type) {
|
|
case KVM_DEV_IRQ_GUEST_INTX:
|
|
r = assigned_device_enable_guest_intx(kvm, dev, irq);
|
|
break;
|
|
#ifdef __KVM_HAVE_MSI
|
|
case KVM_DEV_IRQ_GUEST_MSI:
|
|
r = assigned_device_enable_guest_msi(kvm, dev, irq);
|
|
break;
|
|
#endif
|
|
#ifdef __KVM_HAVE_MSIX
|
|
case KVM_DEV_IRQ_GUEST_MSIX:
|
|
r = assigned_device_enable_guest_msix(kvm, dev, irq);
|
|
break;
|
|
#endif
|
|
default:
|
|
r = -EINVAL;
|
|
}
|
|
|
|
if (!r) {
|
|
dev->irq_requested_type |= guest_irq_type;
|
|
if (dev->ack_notifier.gsi != -1)
|
|
kvm_register_irq_ack_notifier(kvm, &dev->ack_notifier);
|
|
} else
|
|
kvm_free_irq_source_id(kvm, dev->irq_source_id);
|
|
|
|
return r;
|
|
}
|
|
|
|
/* TODO Deal with KVM_DEV_IRQ_ASSIGNED_MASK_MSIX */
|
|
static int kvm_vm_ioctl_assign_irq(struct kvm *kvm,
|
|
struct kvm_assigned_irq *assigned_irq)
|
|
{
|
|
int r = -EINVAL;
|
|
struct kvm_assigned_dev_kernel *match;
|
|
unsigned long host_irq_type, guest_irq_type;
|
|
|
|
if (!irqchip_in_kernel(kvm))
|
|
return r;
|
|
|
|
mutex_lock(&kvm->lock);
|
|
r = -ENODEV;
|
|
match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
|
|
assigned_irq->assigned_dev_id);
|
|
if (!match)
|
|
goto out;
|
|
|
|
host_irq_type = (assigned_irq->flags & KVM_DEV_IRQ_HOST_MASK);
|
|
guest_irq_type = (assigned_irq->flags & KVM_DEV_IRQ_GUEST_MASK);
|
|
|
|
r = -EINVAL;
|
|
/* can only assign one type at a time */
|
|
if (hweight_long(host_irq_type) > 1)
|
|
goto out;
|
|
if (hweight_long(guest_irq_type) > 1)
|
|
goto out;
|
|
if (host_irq_type == 0 && guest_irq_type == 0)
|
|
goto out;
|
|
|
|
r = 0;
|
|
if (host_irq_type)
|
|
r = assign_host_irq(kvm, match, host_irq_type);
|
|
if (r)
|
|
goto out;
|
|
|
|
if (guest_irq_type)
|
|
r = assign_guest_irq(kvm, match, assigned_irq, guest_irq_type);
|
|
out:
|
|
mutex_unlock(&kvm->lock);
|
|
return r;
|
|
}
|
|
|
|
static int kvm_vm_ioctl_deassign_dev_irq(struct kvm *kvm,
|
|
struct kvm_assigned_irq
|
|
*assigned_irq)
|
|
{
|
|
int r = -ENODEV;
|
|
struct kvm_assigned_dev_kernel *match;
|
|
unsigned long irq_type;
|
|
|
|
mutex_lock(&kvm->lock);
|
|
|
|
match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
|
|
assigned_irq->assigned_dev_id);
|
|
if (!match)
|
|
goto out;
|
|
|
|
irq_type = assigned_irq->flags & (KVM_DEV_IRQ_HOST_MASK |
|
|
KVM_DEV_IRQ_GUEST_MASK);
|
|
r = kvm_deassign_irq(kvm, match, irq_type);
|
|
out:
|
|
mutex_unlock(&kvm->lock);
|
|
return r;
|
|
}
|
|
|
|
/*
|
|
* We want to test whether the caller has been granted permissions to
|
|
* use this device. To be able to configure and control the device,
|
|
* the user needs access to PCI configuration space and BAR resources.
|
|
* These are accessed through PCI sysfs. PCI config space is often
|
|
* passed to the process calling this ioctl via file descriptor, so we
|
|
* can't rely on access to that file. We can check for permissions
|
|
* on each of the BAR resource files, which is a pretty clear
|
|
* indicator that the user has been granted access to the device.
|
|
*/
|
|
static int probe_sysfs_permissions(struct pci_dev *dev)
|
|
{
|
|
#ifdef CONFIG_SYSFS
|
|
int i;
|
|
bool bar_found = false;
|
|
|
|
for (i = PCI_STD_RESOURCES; i <= PCI_STD_RESOURCE_END; i++) {
|
|
char *kpath, *syspath;
|
|
struct path path;
|
|
struct inode *inode;
|
|
int r;
|
|
|
|
if (!pci_resource_len(dev, i))
|
|
continue;
|
|
|
|
kpath = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
|
|
if (!kpath)
|
|
return -ENOMEM;
|
|
|
|
/* Per sysfs-rules, sysfs is always at /sys */
|
|
syspath = kasprintf(GFP_KERNEL, "/sys%s/resource%d", kpath, i);
|
|
kfree(kpath);
|
|
if (!syspath)
|
|
return -ENOMEM;
|
|
|
|
r = kern_path(syspath, LOOKUP_FOLLOW, &path);
|
|
kfree(syspath);
|
|
if (r)
|
|
return r;
|
|
|
|
inode = path.dentry->d_inode;
|
|
|
|
r = inode_permission(inode, MAY_READ | MAY_WRITE | MAY_ACCESS);
|
|
path_put(&path);
|
|
if (r)
|
|
return r;
|
|
|
|
bar_found = true;
|
|
}
|
|
|
|
/* If no resources, probably something special */
|
|
if (!bar_found)
|
|
return -EPERM;
|
|
|
|
return 0;
|
|
#else
|
|
return -EINVAL; /* No way to control the device without sysfs */
|
|
#endif
|
|
}
|
|
|
|
static int kvm_vm_ioctl_assign_device(struct kvm *kvm,
|
|
struct kvm_assigned_pci_dev *assigned_dev)
|
|
{
|
|
int r = 0, idx;
|
|
struct kvm_assigned_dev_kernel *match;
|
|
struct pci_dev *dev;
|
|
|
|
if (!(assigned_dev->flags & KVM_DEV_ASSIGN_ENABLE_IOMMU))
|
|
return -EINVAL;
|
|
|
|
mutex_lock(&kvm->lock);
|
|
idx = srcu_read_lock(&kvm->srcu);
|
|
|
|
match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
|
|
assigned_dev->assigned_dev_id);
|
|
if (match) {
|
|
/* device already assigned */
|
|
r = -EEXIST;
|
|
goto out;
|
|
}
|
|
|
|
match = kzalloc(sizeof(struct kvm_assigned_dev_kernel), GFP_KERNEL);
|
|
if (match == NULL) {
|
|
printk(KERN_INFO "%s: Couldn't allocate memory\n",
|
|
__func__);
|
|
r = -ENOMEM;
|
|
goto out;
|
|
}
|
|
dev = pci_get_domain_bus_and_slot(assigned_dev->segnr,
|
|
assigned_dev->busnr,
|
|
assigned_dev->devfn);
|
|
if (!dev) {
|
|
printk(KERN_INFO "%s: host device not found\n", __func__);
|
|
r = -EINVAL;
|
|
goto out_free;
|
|
}
|
|
|
|
/* Don't allow bridges to be assigned */
|
|
if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL) {
|
|
r = -EPERM;
|
|
goto out_put;
|
|
}
|
|
|
|
r = probe_sysfs_permissions(dev);
|
|
if (r)
|
|
goto out_put;
|
|
|
|
if (pci_enable_device(dev)) {
|
|
printk(KERN_INFO "%s: Could not enable PCI device\n", __func__);
|
|
r = -EBUSY;
|
|
goto out_put;
|
|
}
|
|
r = pci_request_regions(dev, "kvm_assigned_device");
|
|
if (r) {
|
|
printk(KERN_INFO "%s: Could not get access to device regions\n",
|
|
__func__);
|
|
goto out_disable;
|
|
}
|
|
|
|
pci_reset_function(dev);
|
|
pci_save_state(dev);
|
|
match->pci_saved_state = pci_store_saved_state(dev);
|
|
if (!match->pci_saved_state)
|
|
printk(KERN_DEBUG "%s: Couldn't store %s saved state\n",
|
|
__func__, dev_name(&dev->dev));
|
|
|
|
if (!pci_intx_mask_supported(dev))
|
|
assigned_dev->flags &= ~KVM_DEV_ASSIGN_PCI_2_3;
|
|
|
|
match->assigned_dev_id = assigned_dev->assigned_dev_id;
|
|
match->host_segnr = assigned_dev->segnr;
|
|
match->host_busnr = assigned_dev->busnr;
|
|
match->host_devfn = assigned_dev->devfn;
|
|
match->flags = assigned_dev->flags;
|
|
match->dev = dev;
|
|
spin_lock_init(&match->intx_lock);
|
|
spin_lock_init(&match->intx_mask_lock);
|
|
match->irq_source_id = -1;
|
|
match->kvm = kvm;
|
|
match->ack_notifier.irq_acked = kvm_assigned_dev_ack_irq;
|
|
|
|
list_add(&match->list, &kvm->arch.assigned_dev_head);
|
|
|
|
if (!kvm->arch.iommu_domain) {
|
|
r = kvm_iommu_map_guest(kvm);
|
|
if (r)
|
|
goto out_list_del;
|
|
}
|
|
r = kvm_assign_device(kvm, match);
|
|
if (r)
|
|
goto out_list_del;
|
|
|
|
out:
|
|
srcu_read_unlock(&kvm->srcu, idx);
|
|
mutex_unlock(&kvm->lock);
|
|
return r;
|
|
out_list_del:
|
|
if (pci_load_and_free_saved_state(dev, &match->pci_saved_state))
|
|
printk(KERN_INFO "%s: Couldn't reload %s saved state\n",
|
|
__func__, dev_name(&dev->dev));
|
|
list_del(&match->list);
|
|
pci_release_regions(dev);
|
|
out_disable:
|
|
pci_disable_device(dev);
|
|
out_put:
|
|
pci_dev_put(dev);
|
|
out_free:
|
|
kfree(match);
|
|
srcu_read_unlock(&kvm->srcu, idx);
|
|
mutex_unlock(&kvm->lock);
|
|
return r;
|
|
}
|
|
|
|
static int kvm_vm_ioctl_deassign_device(struct kvm *kvm,
|
|
struct kvm_assigned_pci_dev *assigned_dev)
|
|
{
|
|
int r = 0;
|
|
struct kvm_assigned_dev_kernel *match;
|
|
|
|
mutex_lock(&kvm->lock);
|
|
|
|
match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
|
|
assigned_dev->assigned_dev_id);
|
|
if (!match) {
|
|
printk(KERN_INFO "%s: device hasn't been assigned before, "
|
|
"so cannot be deassigned\n", __func__);
|
|
r = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
kvm_deassign_device(kvm, match);
|
|
|
|
kvm_free_assigned_device(kvm, match);
|
|
|
|
out:
|
|
mutex_unlock(&kvm->lock);
|
|
return r;
|
|
}
|
|
|
|
|
|
#ifdef __KVM_HAVE_MSIX
|
|
static int kvm_vm_ioctl_set_msix_nr(struct kvm *kvm,
|
|
struct kvm_assigned_msix_nr *entry_nr)
|
|
{
|
|
int r = 0;
|
|
struct kvm_assigned_dev_kernel *adev;
|
|
|
|
mutex_lock(&kvm->lock);
|
|
|
|
adev = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
|
|
entry_nr->assigned_dev_id);
|
|
if (!adev) {
|
|
r = -EINVAL;
|
|
goto msix_nr_out;
|
|
}
|
|
|
|
if (adev->entries_nr == 0) {
|
|
adev->entries_nr = entry_nr->entry_nr;
|
|
if (adev->entries_nr == 0 ||
|
|
adev->entries_nr > KVM_MAX_MSIX_PER_DEV) {
|
|
r = -EINVAL;
|
|
goto msix_nr_out;
|
|
}
|
|
|
|
adev->host_msix_entries = kzalloc(sizeof(struct msix_entry) *
|
|
entry_nr->entry_nr,
|
|
GFP_KERNEL);
|
|
if (!adev->host_msix_entries) {
|
|
r = -ENOMEM;
|
|
goto msix_nr_out;
|
|
}
|
|
adev->guest_msix_entries =
|
|
kzalloc(sizeof(struct msix_entry) * entry_nr->entry_nr,
|
|
GFP_KERNEL);
|
|
if (!adev->guest_msix_entries) {
|
|
kfree(adev->host_msix_entries);
|
|
r = -ENOMEM;
|
|
goto msix_nr_out;
|
|
}
|
|
} else /* Not allowed set MSI-X number twice */
|
|
r = -EINVAL;
|
|
msix_nr_out:
|
|
mutex_unlock(&kvm->lock);
|
|
return r;
|
|
}
|
|
|
|
static int kvm_vm_ioctl_set_msix_entry(struct kvm *kvm,
|
|
struct kvm_assigned_msix_entry *entry)
|
|
{
|
|
int r = 0, i;
|
|
struct kvm_assigned_dev_kernel *adev;
|
|
|
|
mutex_lock(&kvm->lock);
|
|
|
|
adev = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
|
|
entry->assigned_dev_id);
|
|
|
|
if (!adev) {
|
|
r = -EINVAL;
|
|
goto msix_entry_out;
|
|
}
|
|
|
|
for (i = 0; i < adev->entries_nr; i++)
|
|
if (adev->guest_msix_entries[i].vector == 0 ||
|
|
adev->guest_msix_entries[i].entry == entry->entry) {
|
|
adev->guest_msix_entries[i].entry = entry->entry;
|
|
adev->guest_msix_entries[i].vector = entry->gsi;
|
|
adev->host_msix_entries[i].entry = entry->entry;
|
|
break;
|
|
}
|
|
if (i == adev->entries_nr) {
|
|
r = -ENOSPC;
|
|
goto msix_entry_out;
|
|
}
|
|
|
|
msix_entry_out:
|
|
mutex_unlock(&kvm->lock);
|
|
|
|
return r;
|
|
}
|
|
#endif
|
|
|
|
static int kvm_vm_ioctl_set_pci_irq_mask(struct kvm *kvm,
|
|
struct kvm_assigned_pci_dev *assigned_dev)
|
|
{
|
|
int r = 0;
|
|
struct kvm_assigned_dev_kernel *match;
|
|
|
|
mutex_lock(&kvm->lock);
|
|
|
|
match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
|
|
assigned_dev->assigned_dev_id);
|
|
if (!match) {
|
|
r = -ENODEV;
|
|
goto out;
|
|
}
|
|
|
|
spin_lock(&match->intx_mask_lock);
|
|
|
|
match->flags &= ~KVM_DEV_ASSIGN_MASK_INTX;
|
|
match->flags |= assigned_dev->flags & KVM_DEV_ASSIGN_MASK_INTX;
|
|
|
|
if (match->irq_requested_type & KVM_DEV_IRQ_GUEST_INTX) {
|
|
if (assigned_dev->flags & KVM_DEV_ASSIGN_MASK_INTX) {
|
|
kvm_set_irq(match->kvm, match->irq_source_id,
|
|
match->guest_irq, 0);
|
|
/*
|
|
* Masking at hardware-level is performed on demand,
|
|
* i.e. when an IRQ actually arrives at the host.
|
|
*/
|
|
} else if (!(assigned_dev->flags & KVM_DEV_ASSIGN_PCI_2_3)) {
|
|
/*
|
|
* Unmask the IRQ line if required. Unmasking at
|
|
* device level will be performed by user space.
|
|
*/
|
|
spin_lock_irq(&match->intx_lock);
|
|
if (match->host_irq_disabled) {
|
|
enable_irq(match->host_irq);
|
|
match->host_irq_disabled = false;
|
|
}
|
|
spin_unlock_irq(&match->intx_lock);
|
|
}
|
|
}
|
|
|
|
spin_unlock(&match->intx_mask_lock);
|
|
|
|
out:
|
|
mutex_unlock(&kvm->lock);
|
|
return r;
|
|
}
|
|
|
|
long kvm_vm_ioctl_assigned_device(struct kvm *kvm, unsigned ioctl,
|
|
unsigned long arg)
|
|
{
|
|
void __user *argp = (void __user *)arg;
|
|
int r;
|
|
|
|
switch (ioctl) {
|
|
case KVM_ASSIGN_PCI_DEVICE: {
|
|
struct kvm_assigned_pci_dev assigned_dev;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
|
|
goto out;
|
|
r = kvm_vm_ioctl_assign_device(kvm, &assigned_dev);
|
|
if (r)
|
|
goto out;
|
|
break;
|
|
}
|
|
case KVM_ASSIGN_IRQ: {
|
|
r = -EOPNOTSUPP;
|
|
break;
|
|
}
|
|
case KVM_ASSIGN_DEV_IRQ: {
|
|
struct kvm_assigned_irq assigned_irq;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&assigned_irq, argp, sizeof assigned_irq))
|
|
goto out;
|
|
r = kvm_vm_ioctl_assign_irq(kvm, &assigned_irq);
|
|
if (r)
|
|
goto out;
|
|
break;
|
|
}
|
|
case KVM_DEASSIGN_DEV_IRQ: {
|
|
struct kvm_assigned_irq assigned_irq;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&assigned_irq, argp, sizeof assigned_irq))
|
|
goto out;
|
|
r = kvm_vm_ioctl_deassign_dev_irq(kvm, &assigned_irq);
|
|
if (r)
|
|
goto out;
|
|
break;
|
|
}
|
|
case KVM_DEASSIGN_PCI_DEVICE: {
|
|
struct kvm_assigned_pci_dev assigned_dev;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
|
|
goto out;
|
|
r = kvm_vm_ioctl_deassign_device(kvm, &assigned_dev);
|
|
if (r)
|
|
goto out;
|
|
break;
|
|
}
|
|
#ifdef KVM_CAP_IRQ_ROUTING
|
|
case KVM_SET_GSI_ROUTING: {
|
|
struct kvm_irq_routing routing;
|
|
struct kvm_irq_routing __user *urouting;
|
|
struct kvm_irq_routing_entry *entries;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&routing, argp, sizeof(routing)))
|
|
goto out;
|
|
r = -EINVAL;
|
|
if (routing.nr >= KVM_MAX_IRQ_ROUTES)
|
|
goto out;
|
|
if (routing.flags)
|
|
goto out;
|
|
r = -ENOMEM;
|
|
entries = vmalloc(routing.nr * sizeof(*entries));
|
|
if (!entries)
|
|
goto out;
|
|
r = -EFAULT;
|
|
urouting = argp;
|
|
if (copy_from_user(entries, urouting->entries,
|
|
routing.nr * sizeof(*entries)))
|
|
goto out_free_irq_routing;
|
|
r = kvm_set_irq_routing(kvm, entries, routing.nr,
|
|
routing.flags);
|
|
out_free_irq_routing:
|
|
vfree(entries);
|
|
break;
|
|
}
|
|
#endif /* KVM_CAP_IRQ_ROUTING */
|
|
#ifdef __KVM_HAVE_MSIX
|
|
case KVM_ASSIGN_SET_MSIX_NR: {
|
|
struct kvm_assigned_msix_nr entry_nr;
|
|
r = -EFAULT;
|
|
if (copy_from_user(&entry_nr, argp, sizeof entry_nr))
|
|
goto out;
|
|
r = kvm_vm_ioctl_set_msix_nr(kvm, &entry_nr);
|
|
if (r)
|
|
goto out;
|
|
break;
|
|
}
|
|
case KVM_ASSIGN_SET_MSIX_ENTRY: {
|
|
struct kvm_assigned_msix_entry entry;
|
|
r = -EFAULT;
|
|
if (copy_from_user(&entry, argp, sizeof entry))
|
|
goto out;
|
|
r = kvm_vm_ioctl_set_msix_entry(kvm, &entry);
|
|
if (r)
|
|
goto out;
|
|
break;
|
|
}
|
|
#endif
|
|
case KVM_ASSIGN_SET_INTX_MASK: {
|
|
struct kvm_assigned_pci_dev assigned_dev;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&assigned_dev, argp, sizeof assigned_dev))
|
|
goto out;
|
|
r = kvm_vm_ioctl_set_pci_irq_mask(kvm, &assigned_dev);
|
|
break;
|
|
}
|
|
default:
|
|
r = -ENOTTY;
|
|
break;
|
|
}
|
|
out:
|
|
return r;
|
|
}
|