1 files changed, 243 insertions, 0 deletions

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 94a216562f10..a97157cc42ae 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4,10 +4,14 @@
  * derived from drivers/kvm/kvm_main.c
  *
  * Copyright (C) 2006 Qumranet, Inc.
+ * Copyright (C) 2008 Qumranet, Inc.
+ * Copyright IBM Corporation, 2008
  *
  * Authors:
  *   Avi Kivity   <avi@qumranet.com>
  *   Yaniv Kamay  <yaniv@qumranet.com>
+ *   Amit Shah    <amit.shah@qumranet.com>
+ *   Ben-Ami Yassour <benami@il.ibm.com>
  *
  * This work is licensed under the terms of the GNU GPL, version 2.  See
  * the COPYING file in the top-level directory.
@@ -23,8 +27,10 @@
 #include "x86.h"
 
 #include <linux/clocksource.h>
+#include <linux/interrupt.h>
 #include <linux/kvm.h>
 #include <linux/fs.h>
+#include <linux/pci.h>
 #include <linux/vmalloc.h>
 #include <linux/module.h>
 #include <linux/mman.h>
@@ -98,6 +104,219 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
         { NULL }
 };
 
+struct kvm_assigned_dev_kernel *kvm_find_assigned_dev(struct list_head *head,
+                                                      int assigned_dev_id)
+{
+        struct list_head *ptr;
+        struct kvm_assigned_dev_kernel *match;
+
+        list_for_each(ptr, head) {
+                match = list_entry(ptr, struct kvm_assigned_dev_kernel, list);
+                if (match->assigned_dev_id == assigned_dev_id)
+                        return match;
+        }
+        return NULL;
+}
+
+static void kvm_assigned_dev_interrupt_work_handler(struct work_struct *work)
+{
+        struct kvm_assigned_dev_kernel *assigned_dev;
+
+        assigned_dev = container_of(work, struct kvm_assigned_dev_kernel,
+                                    interrupt_work);
+
+        /* This is taken to safely inject irq inside the guest. When
+         * the interrupt injection (or the ioapic code) uses a
+         * finer-grained lock, update this
+         */
+        mutex_lock(&assigned_dev->kvm->lock);
+        kvm_set_irq(assigned_dev->kvm,
+                    assigned_dev->guest_irq, 1);
+        mutex_unlock(&assigned_dev->kvm->lock);
+        kvm_put_kvm(assigned_dev->kvm);
+}
+
+/* FIXME: Implement the OR logic needed to make shared interrupts on
+ * this line behave properly
+ */
+static irqreturn_t kvm_assigned_dev_intr(int irq, void *dev_id)
+{
+        struct kvm_assigned_dev_kernel *assigned_dev =
+                (struct kvm_assigned_dev_kernel *) dev_id;
+
+        kvm_get_kvm(assigned_dev->kvm);
+        schedule_work(&assigned_dev->interrupt_work);
+        disable_irq_nosync(irq);
+        return IRQ_HANDLED;
+}
+
+/* Ack the irq line for an assigned device */
+static void kvm_assigned_dev_ack_irq(struct kvm_irq_ack_notifier *kian)
+{
+        struct kvm_assigned_dev_kernel *dev;
+
+        if (kian->gsi == -1)
+                return;
+
+        dev = container_of(kian, struct kvm_assigned_dev_kernel,
+                           ack_notifier);
+        kvm_set_irq(dev->kvm, dev->guest_irq, 0);
+        enable_irq(dev->host_irq);
+}
+
+static int kvm_vm_ioctl_assign_irq(struct kvm *kvm,
+                                   struct kvm_assigned_irq
+                                   *assigned_irq)
+{
+        int r = 0;
+        struct kvm_assigned_dev_kernel *match;
+
+        mutex_lock(&kvm->lock);
+
+        match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
+                                      assigned_irq->assigned_dev_id);
+        if (!match) {
+                mutex_unlock(&kvm->lock);
+                return -EINVAL;
+        }
+
+        if (match->irq_requested) {
+                match->guest_irq = assigned_irq->guest_irq;
+                match->ack_notifier.gsi = assigned_irq->guest_irq;
+                mutex_unlock(&kvm->lock);
+                return 0;
+        }
+
+        INIT_WORK(&match->interrupt_work,
+                  kvm_assigned_dev_interrupt_work_handler);
+
+        if (irqchip_in_kernel(kvm)) {
+                if (assigned_irq->host_irq)
+                        match->host_irq = assigned_irq->host_irq;
+                else
+                        match->host_irq = match->dev->irq;
+                match->guest_irq = assigned_irq->guest_irq;
+                match->ack_notifier.gsi = assigned_irq->guest_irq;
+                match->ack_notifier.irq_acked = kvm_assigned_dev_ack_irq;
+                kvm_register_irq_ack_notifier(kvm, &match->ack_notifier);
+
+                /* Even though this is PCI, we don't want to use shared
+                 * interrupts. Sharing host devices with guest-assigned devices
+                 * on the same interrupt line is not a happy situation: there
+                 * are going to be long delays in accepting, acking, etc.
+                 */
+                if (request_irq(match->host_irq, kvm_assigned_dev_intr, 0,
+                                "kvm_assigned_device", (void *)match)) {
+                        printk(KERN_INFO "%s: couldn't allocate irq for pv "
+                               "device\n", __func__);
+                        r = -EIO;
+                        goto out;
+                }
+        }
+
+        match->irq_requested = true;
+out:
+        mutex_unlock(&kvm->lock);
+        return r;
+}
+
+static int kvm_vm_ioctl_assign_device(struct kvm *kvm,
+                                      struct kvm_assigned_pci_dev *assigned_dev)
+{
+        int r = 0;
+        struct kvm_assigned_dev_kernel *match;
+        struct pci_dev *dev;
+
+        mutex_lock(&kvm->lock);
+
+        match = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
+                                      assigned_dev->assigned_dev_id);
+        if (match) {
+                /* device already assigned */
+                r = -EINVAL;
+                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_bus_and_slot(assigned_dev->busnr,
+                                   assigned_dev->devfn);
+        if (!dev) {
+                printk(KERN_INFO "%s: host device not found\n", __func__);
+                r = -EINVAL;
+                goto out_free;
+        }
+        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;
+        }
+        match->assigned_dev_id = assigned_dev->assigned_dev_id;
+        match->host_busnr = assigned_dev->busnr;
+        match->host_devfn = assigned_dev->devfn;
+        match->dev = dev;
+
+        match->kvm = kvm;
+
+        list_add(&match->list, &kvm->arch.assigned_dev_head);
+
+out:
+        mutex_unlock(&kvm->lock);
+        return r;
+out_disable:
+        pci_disable_device(dev);
+out_put:
+        pci_dev_put(dev);
+out_free:
+        kfree(match);
+        mutex_unlock(&kvm->lock);
+        return r;
+}
+
+static void kvm_free_assigned_devices(struct kvm *kvm)
+{
+        struct list_head *ptr, *ptr2;
+        struct kvm_assigned_dev_kernel *assigned_dev;
+
+        list_for_each_safe(ptr, ptr2, &kvm->arch.assigned_dev_head) {
+                assigned_dev = list_entry(ptr,
+                                          struct kvm_assigned_dev_kernel,
+                                          list);
+
+                if (irqchip_in_kernel(kvm) && assigned_dev->irq_requested) {
+                        free_irq(assigned_dev->host_irq,
+                                 (void *)assigned_dev);
+
+                        kvm_unregister_irq_ack_notifier(kvm,
+                                                        &assigned_dev->
+                                                        ack_notifier);
+                }
+
+                if (cancel_work_sync(&assigned_dev->interrupt_work))
+                        /* We had pending work. That means we will have to take
+                         * care of kvm_put_kvm.
+                         */
+                        kvm_put_kvm(kvm);
+
+                pci_release_regions(assigned_dev->dev);
+                pci_disable_device(assigned_dev->dev);
+                pci_dev_put(assigned_dev->dev);
+
+                list_del(&assigned_dev->list);
+                kfree(assigned_dev);
+        }
+}
 
 unsigned long segment_base(u16 selector)
 {
@@ -1766,6 +1985,28 @@ long kvm_arch_vm_ioctl(struct file *filp,
                 r = 0;
                 break;
         }
+        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: {
+                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_GET_PIT: {
                 struct kvm_pit_state ps;
                 r = -EFAULT;
@@ -3945,6 +4186,7 @@ struct  kvm *kvm_arch_create_vm(void)
                 return ERR_PTR(-ENOMEM);
 
         INIT_LIST_HEAD(&kvm->arch.active_mmu_pages);
+        INIT_LIST_HEAD(&kvm->arch.assigned_dev_head);
 
         return kvm;
 }
@@ -3977,6 +4219,7 @@ static void kvm_free_vcpus(struct kvm *kvm)
 
 void kvm_arch_destroy_vm(struct kvm *kvm)
 {
+        kvm_free_assigned_devices(kvm);
         kvm_free_pit(kvm);
         kfree(kvm->arch.vpic);
         kfree(kvm->arch.vioapic);