File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/arch/x86/kvm/assigned-dev.c b/arch/x86/kvm/assigned-dev.c
new file mode 100644
index 0000000..9dc091a
--- /dev/null
+++ b/arch/x86/kvm/assigned-dev.c
@@ -0,0 +1,1064 @@
+/*
+ * Kernel-based Virtual Machine - device assignment support
+ *
+ * Copyright (C) 2010 Red Hat, Inc. and/or its affiliates.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include <linux/kvm_host.h>
+#include <linux/kvm.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+#include <linux/errno.h>
+#include <linux/spinlock.h>
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/namei.h>
+#include <linux/fs.h>
+#include "irq.h"
+#include "assigned-dev.h"
+#include "trace/events/kvm.h"
+
+struct kvm_assigned_dev_kernel {
+ struct kvm_irq_ack_notifier ack_notifier;
+ struct list_head list;
+ int assigned_dev_id;
+ int host_segnr;
+ int host_busnr;
+ int host_devfn;
+ unsigned int entries_nr;
+ int host_irq;
+ bool host_irq_disabled;
+ bool pci_2_3;
+ struct msix_entry *host_msix_entries;
+ int guest_irq;
+ struct msix_entry *guest_msix_entries;
+ unsigned long irq_requested_type;
+ int irq_source_id;
+ int flags;
+ struct pci_dev *dev;
+ struct kvm *kvm;
+ spinlock_t intx_lock;
+ spinlock_t intx_mask_lock;
+ char irq_name[32];
+ struct pci_saved_state *pci_saved_state;
+};
+
+static 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 int find_index_from_host_irq(struct kvm_assigned_dev_kernel
+ *assigned_dev, int irq)
+{
+ int i, index;
+ struct msix_entry *host_msix_entries;
+
+ host_msix_entries = assigned_dev->host_msix_entries;
+
+ index = -1;
+ for (i = 0; i < assigned_dev->entries_nr; i++)
+ if (irq == host_msix_entries[i].vector) {
+ index = i;
+ break;
+ }
+ if (index < 0)
+ printk(KERN_WARNING "Fail to find correlated MSI-X entry!\n");
+
+ return index;
+}
+
+static irqreturn_t kvm_assigned_dev_intx(int irq, void *dev_id)
+{
+ struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
+ int ret;
+
+ spin_lock(&assigned_dev->intx_lock);
+ if (pci_check_and_mask_intx(assigned_dev->dev)) {
+ assigned_dev->host_irq_disabled = true;
+ ret = IRQ_WAKE_THREAD;
+ } else
+ ret = IRQ_NONE;
+ spin_unlock(&assigned_dev->intx_lock);
+
+ return ret;
+}
+
+static void
+kvm_assigned_dev_raise_guest_irq(struct kvm_assigned_dev_kernel *assigned_dev,
+ int vector)
+{
+ if (unlikely(assigned_dev->irq_requested_type &
+ KVM_DEV_IRQ_GUEST_INTX)) {
+ spin_lock(&assigned_dev->intx_mask_lock);
+ if (!(assigned_dev->flags & KVM_DEV_ASSIGN_MASK_INTX))
+ kvm_set_irq(assigned_dev->kvm,
+ assigned_dev->irq_source_id, vector, 1,
+ false);
+ spin_unlock(&assigned_dev->intx_mask_lock);
+ } else
+ kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id,
+ vector, 1, false);
+}
+
+static irqreturn_t kvm_assigned_dev_thread_intx(int irq, void *dev_id)
+{
+ struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
+
+ if (!(assigned_dev->flags & KVM_DEV_ASSIGN_PCI_2_3)) {
+ spin_lock_irq(&assigned_dev->intx_lock);
+ disable_irq_nosync(irq);
+ assigned_dev->host_irq_disabled = true;
+ spin_unlock_irq(&assigned_dev->intx_lock);
+ }
+
+ kvm_assigned_dev_raise_guest_irq(assigned_dev,
+ assigned_dev->guest_irq);
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * Deliver an IRQ in an atomic context if we can, or return a failure,
+ * user can retry in a process context.
+ * Return value:
+ * -EWOULDBLOCK - Can't deliver in atomic context: retry in a process context.
+ * Other values - No need to retry.
+ */
+static int kvm_set_irq_inatomic(struct kvm *kvm, int irq_source_id, u32 irq,
+ int level)
+{
+ struct kvm_kernel_irq_routing_entry entries[KVM_NR_IRQCHIPS];
+ struct kvm_kernel_irq_routing_entry *e;
+ int ret = -EINVAL;
+ int idx;
+
+ trace_kvm_set_irq(irq, level, irq_source_id);
+
+ /*
+ * Injection into either PIC or IOAPIC might need to scan all CPUs,
+ * which would need to be retried from thread context; when same GSI
+ * is connected to both PIC and IOAPIC, we'd have to report a
+ * partial failure here.
+ * Since there's no easy way to do this, we only support injecting MSI
+ * which is limited to 1:1 GSI mapping.
+ */
+ idx = srcu_read_lock(&kvm->irq_srcu);
+ if (kvm_irq_map_gsi(kvm, entries, irq) > 0) {
+ e = &entries[0];
+ ret = kvm_arch_set_irq_inatomic(e, kvm, irq_source_id,
+ irq, level);
+ }
+ srcu_read_unlock(&kvm->irq_srcu, idx);
+ return ret;
+}
+
+
+static irqreturn_t kvm_assigned_dev_msi(int irq, void *dev_id)
+{
+ struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
+ int ret = kvm_set_irq_inatomic(assigned_dev->kvm,
+ assigned_dev->irq_source_id,
+ assigned_dev->guest_irq, 1);
+ return unlikely(ret == -EWOULDBLOCK) ? IRQ_WAKE_THREAD : IRQ_HANDLED;
+}
+
+static irqreturn_t kvm_assigned_dev_thread_msi(int irq, void *dev_id)
+{
+ struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
+
+ kvm_assigned_dev_raise_guest_irq(assigned_dev,
+ assigned_dev->guest_irq);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t kvm_assigned_dev_msix(int irq, void *dev_id)
+{
+ struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
+ int index = find_index_from_host_irq(assigned_dev, irq);
+ u32 vector;
+ int ret = 0;
+
+ if (index >= 0) {
+ vector = assigned_dev->guest_msix_entries[index].vector;
+ ret = kvm_set_irq_inatomic(assigned_dev->kvm,
+ assigned_dev->irq_source_id,
+ vector, 1);
+ }
+
+ return unlikely(ret == -EWOULDBLOCK) ? IRQ_WAKE_THREAD : IRQ_HANDLED;
+}
+
+static irqreturn_t kvm_assigned_dev_thread_msix(int irq, void *dev_id)
+{
+ struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
+ int index = find_index_from_host_irq(assigned_dev, irq);
+ u32 vector;
+
+ if (index >= 0) {
+ vector = assigned_dev->guest_msix_entries[index].vector;
+ kvm_assigned_dev_raise_guest_irq(assigned_dev, vector);
+ }
+
+ 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 =
+ container_of(kian, struct kvm_assigned_dev_kernel,
+ ack_notifier);
+
+ kvm_set_irq(dev->kvm, dev->irq_source_id, dev->guest_irq, 0, false);
+
+ spin_lock(&dev->intx_mask_lock);
+
+ if (!(dev->flags & KVM_DEV_ASSIGN_MASK_INTX)) {
+ bool reassert = false;
+
+ spin_lock_irq(&dev->intx_lock);
+ /*
+ * The guest IRQ may be shared so this ack can come from an
+ * IRQ for another guest device.
+ */
+ if (dev->host_irq_disabled) {
+ if (!(dev->flags & KVM_DEV_ASSIGN_PCI_2_3))
+ enable_irq(dev->host_irq);
+ else if (!pci_check_and_unmask_intx(dev->dev))
+ reassert = true;
+ dev->host_irq_disabled = reassert;
+ }
+ spin_unlock_irq(&dev->intx_lock);
+
+ if (reassert)
+ kvm_set_irq(dev->kvm, dev->irq_source_id,
+ dev->guest_irq, 1, false);
+ }
+
+ spin_unlock(&dev->intx_mask_lock);
+}
+
+static void deassign_guest_irq(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *assigned_dev)
+{
+ if (assigned_dev->ack_notifier.gsi != -1)
+ kvm_unregister_irq_ack_notifier(kvm,
+ &assigned_dev->ack_notifier);
+
+ kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id,
+ assigned_dev->guest_irq, 0, false);
+
+ if (assigned_dev->irq_source_id != -1)
+ kvm_free_irq_source_id(kvm, assigned_dev->irq_source_id);
+ assigned_dev->irq_source_id = -1;
+ assigned_dev->irq_requested_type &= ~(KVM_DEV_IRQ_GUEST_MASK);
+}
+
+/* The function implicit hold kvm->lock mutex due to cancel_work_sync() */
+static void deassign_host_irq(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *assigned_dev)
+{
+ /*
+ * We disable irq here to prevent further events.
+ *
+ * Notice this maybe result in nested disable if the interrupt type is
+ * INTx, but it's OK for we are going to free it.
+ *
+ * If this function is a part of VM destroy, please ensure that till
+ * now, the kvm state is still legal for probably we also have to wait
+ * on a currently running IRQ handler.
+ */
+ if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSIX) {
+ int i;
+ for (i = 0; i < assigned_dev->entries_nr; i++)
+ disable_irq(assigned_dev->host_msix_entries[i].vector);
+
+ for (i = 0; i < assigned_dev->entries_nr; i++)
+ free_irq(assigned_dev->host_msix_entries[i].vector,
+ assigned_dev);
+
+ assigned_dev->entries_nr = 0;
+ kfree(assigned_dev->host_msix_entries);
+ kfree(assigned_dev->guest_msix_entries);
+ pci_disable_msix(assigned_dev->dev);
+ } else {
+ /* Deal with MSI and INTx */
+ if ((assigned_dev->irq_requested_type &
+ KVM_DEV_IRQ_HOST_INTX) &&
+ (assigned_dev->flags & KVM_DEV_ASSIGN_PCI_2_3)) {
+ spin_lock_irq(&assigned_dev->intx_lock);
+ pci_intx(assigned_dev->dev, false);
+ spin_unlock_irq(&assigned_dev->intx_lock);
+ synchronize_irq(assigned_dev->host_irq);
+ } else
+ disable_irq(assigned_dev->host_irq);
+
+ free_irq(assigned_dev->host_irq, assigned_dev);
+
+ if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSI)
+ pci_disable_msi(assigned_dev->dev);
+ }
+
+ assigned_dev->irq_requested_type &= ~(KVM_DEV_IRQ_HOST_MASK);
+}
+
+static int kvm_deassign_irq(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *assigned_dev,
+ unsigned long irq_requested_type)
+{
+ unsigned long guest_irq_type, host_irq_type;
+
+ if (!irqchip_in_kernel(kvm))
+ return -EINVAL;
+ /* no irq assignment to deassign */
+ if (!assigned_dev->irq_requested_type)
+ return -ENXIO;
+
+ host_irq_type = irq_requested_type & KVM_DEV_IRQ_HOST_MASK;
+ guest_irq_type = irq_requested_type & KVM_DEV_IRQ_GUEST_MASK;
+
+ if (host_irq_type)
+ deassign_host_irq(kvm, assigned_dev);
+ if (guest_irq_type)
+ deassign_guest_irq(kvm, assigned_dev);
+
+ return 0;
+}
+
+static void kvm_free_assigned_irq(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *assigned_dev)
+{
+ kvm_deassign_irq(kvm, assigned_dev, assigned_dev->irq_requested_type);
+}
+
+static void kvm_free_assigned_device(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel
+ *assigned_dev)
+{
+ kvm_free_assigned_irq(kvm, assigned_dev);
+
+ pci_reset_function(assigned_dev->dev);
+ if (pci_load_and_free_saved_state(assigned_dev->dev,
+ &assigned_dev->pci_saved_state))
+ printk(KERN_INFO "%s: Couldn't reload %s saved state\n",
+ __func__, dev_name(&assigned_dev->dev->dev));
+ else
+ pci_restore_state(assigned_dev->dev);
+
+ pci_clear_dev_assigned(assigned_dev->dev);
+
+ 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);
+}
+
+void kvm_free_all_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);
+
+ kvm_free_assigned_device(kvm, assigned_dev);
+ }
+}
+
+static int assigned_device_enable_host_intx(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *dev)
+{
+ irq_handler_t irq_handler;
+ unsigned long flags;
+
+ dev->host_irq = dev->dev->irq;
+
+ /*
+ * We can only share the IRQ line with other host devices if we are
+ * able to disable the IRQ source at device-level - independently of
+ * the guest driver. Otherwise host devices may suffer from unbounded
+ * IRQ latencies when the guest keeps the line asserted.
+ */
+ if (dev->flags & KVM_DEV_ASSIGN_PCI_2_3) {
+ irq_handler = kvm_assigned_dev_intx;
+ flags = IRQF_SHARED;
+ } else {
+ irq_handler = NULL;
+ flags = IRQF_ONESHOT;
+ }
+ if (request_threaded_irq(dev->host_irq, irq_handler,
+ kvm_assigned_dev_thread_intx, flags,
+ dev->irq_name, dev))
+ return -EIO;
+
+ if (dev->flags & KVM_DEV_ASSIGN_PCI_2_3) {
+ spin_lock_irq(&dev->intx_lock);
+ pci_intx(dev->dev, true);
+ spin_unlock_irq(&dev->intx_lock);
+ }
+ return 0;
+}
+
+static int assigned_device_enable_host_msi(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *dev)
+{
+ int r;
+
+ if (!dev->dev->msi_enabled) {
+ r = pci_enable_msi(dev->dev);
+ if (r)
+ return r;
+ }
+
+ dev->host_irq = dev->dev->irq;
+ if (request_threaded_irq(dev->host_irq, kvm_assigned_dev_msi,
+ kvm_assigned_dev_thread_msi, 0,
+ dev->irq_name, dev)) {
+ pci_disable_msi(dev->dev);
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int assigned_device_enable_host_msix(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *dev)
+{
+ int i, r = -EINVAL;
+
+ /* host_msix_entries and guest_msix_entries should have been
+ * initialized */
+ if (dev->entries_nr == 0)
+ return r;
+
+ r = pci_enable_msix_exact(dev->dev,
+ dev->host_msix_entries, dev->entries_nr);
+ if (r)
+ return r;
+
+ for (i = 0; i < dev->entries_nr; i++) {
+ r = request_threaded_irq(dev->host_msix_entries[i].vector,
+ kvm_assigned_dev_msix,
+ kvm_assigned_dev_thread_msix,
+ 0, dev->irq_name, dev);
+ if (r)
+ goto err;
+ }
+
+ return 0;
+err:
+ for (i -= 1; i >= 0; i--)
+ free_irq(dev->host_msix_entries[i].vector, dev);
+ pci_disable_msix(dev->dev);
+ return r;
+}
+
+static int assigned_device_enable_guest_intx(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *dev,
+ struct kvm_assigned_irq *irq)
+{
+ dev->guest_irq = irq->guest_irq;
+ dev->ack_notifier.gsi = irq->guest_irq;
+ return 0;
+}
+
+static int assigned_device_enable_guest_msi(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *dev,
+ struct kvm_assigned_irq *irq)
+{
+ dev->guest_irq = irq->guest_irq;
+ dev->ack_notifier.gsi = -1;
+ return 0;
+}
+
+static int assigned_device_enable_guest_msix(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *dev,
+ struct kvm_assigned_irq *irq)
+{
+ dev->guest_irq = irq->guest_irq;
+ dev->ack_notifier.gsi = -1;
+ return 0;
+}
+
+static int assign_host_irq(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *dev,
+ __u32 host_irq_type)
+{
+ int r = -EEXIST;
+
+ if (dev->irq_requested_type & KVM_DEV_IRQ_HOST_MASK)
+ return r;
+
+ snprintf(dev->irq_name, sizeof(dev->irq_name), "kvm:%s",
+ pci_name(dev->dev));
+
+ switch (host_irq_type) {
+ case KVM_DEV_IRQ_HOST_INTX:
+ r = assigned_device_enable_host_intx(kvm, dev);
+ break;
+ case KVM_DEV_IRQ_HOST_MSI:
+ r = assigned_device_enable_host_msi(kvm, dev);
+ break;
+ case KVM_DEV_IRQ_HOST_MSIX:
+ r = assigned_device_enable_host_msix(kvm, dev);
+ break;
+ default:
+ r = -EINVAL;
+ }
+ dev->host_irq_disabled = false;
+
+ if (!r)
+ dev->irq_requested_type |= host_irq_type;
+
+ return r;
+}
+
+static int assign_guest_irq(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *dev,
+ struct kvm_assigned_irq *irq,
+ unsigned long guest_irq_type)
+{
+ int id;
+ 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;
+ case KVM_DEV_IRQ_GUEST_MSI:
+ r = assigned_device_enable_guest_msi(kvm, dev, irq);
+ break;
+ case KVM_DEV_IRQ_GUEST_MSIX:
+ r = assigned_device_enable_guest_msix(kvm, dev, irq);
+ break;
+ 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);
+ dev->irq_source_id = -1;
+ }
+
+ 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 = d_backing_inode(path.dentry);
+
+ 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->dev);
+ 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->dev);
+
+ kvm_free_assigned_device(kvm, match);
+
+out:
+ mutex_unlock(&kvm->lock);
+ return r;
+}
+
+
+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;
+}
+
+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, false);
+ /*
+ * 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;
+ }
+ 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;
+ }
+ 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;
+}