[PATCH 1/3] KVM: Ioctls for init MSI-X entry

Sheng Yang
2009-02-12T10:07:51Z

Introduce KVM_SET_MSIX_NR and KVM_SET_MSIX_ENTRY two ioctls.

This two ioctls are used by userspace to specific guest device MSI-X entry
number and correlate MSI-X entry with GSI during the initialization stage.

MSI-X should be well initialzed before enabling.

Don't support change MSI-X entry number for now.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
---
include/linux/kvm.h | 15 +++++++
include/linux/kvm_host.h | 3 +
virt/kvm/kvm_main.c | 101 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 119 insertions(+), 0 deletions(-)

diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index 2163b3d..c76ea44 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -475,6 +475,8 @@ struct kvm_irq_routing {
#define KVM_ASSIGN_IRQ _IOR(KVMIO, 0x70, \
struct kvm_assigned_irq)
#define KVM_REINJECT_CONTROL _IO(KVMIO, 0x71)
+#define KVM_SET_MSIX_NR _IOR(KVMIO, 0x72, struct kvm_assigned_msix_nr)
+#define KVM_SET_MSIX_ENTRY _IOR(KVMIO, 0x73, struct kvm_assigned_msix_entry)

/*
* ioctls for vcpu fds
@@ -595,4 +597,17 @@ struct kvm_assigned_irq {
#define KVM_DEV_IRQ_ASSIGN_MSI_ACTION KVM_DEV_IRQ_ASSIGN_ENABLE_MSI
#define KVM_DEV_IRQ_ASSIGN_ENABLE_MSI (1 << 0)

+struct kvm_assigned_msix_nr {
+ __u32 assigned_dev_id;
+ __u16 entry_nr;
+ __u16 padding;
+};
+
+struct kvm_assigned_msix_entry {
+ __u32 assigned_dev_id;
+ __u32 gsi;
+ __u16 entry; /* The index of entry in the MSI-X table */
+ __u16 padding[3];
+};
+
#endif
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 7c7096d..ac4d63c 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -326,9 +326,12 @@ struct kvm_assigned_dev_kernel {
int assigned_dev_id;
int host_busnr;
int host_devfn;
+ int entries_nr;
int host_irq;
bool host_irq_disabled;
+ struct msix_entry *host_msix_entries;
int guest_irq;
+ struct msix_entry *guest_msix_entries;
#define KVM_ASSIGNED_DEV_GUEST_INTX (1 << 0)
#define KVM_ASSIGNED_DEV_GUEST_MSI (1 << 1)
#define KVM_ASSIGNED_DEV_HOST_INTX (1 << 8)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 266bdaf..f395160 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1593,6 +1593,85 @@ static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
return 0;
}

+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)
+ goto msix_nr_out;
+
+ adev->host_msix_entries = kzalloc(sizeof(struct msix_entry) *
+ entry_nr->entry_nr,
+ GFP_KERNEL);
+ if (!adev->host_msix_entries) {
+ printk(KERN_ERR "no memory for host msix entries!\n");
+ 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) {
+ printk(KERN_ERR "no memory for host msix entries!\n");
+ r = -ENOMEM;
+ goto msix_nr_out;
+ }
+ } else
+ printk(KERN_WARNING "kvm: not allow recall set msix nr!\n");
+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) {
+ printk(KERN_ERR "kvm: Too much entries for MSI-X!\n");
+ r = -ENOSPC;
+ goto msix_entry_out;
+ }
+
+msix_entry_out:
+ mutex_unlock(&kvm->lock);
+
+ return r;
+}
+
static long kvm_vcpu_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
@@ -1917,7 +1996,29 @@ static long kvm_vm_ioctl(struct file *filp,
vfree(entries);
break;
}
+#ifdef KVM_CAP_DEVICE_MSIX
+ case KVM_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_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
+#endif /* KVM_CAP_IRQ_ROUTING */
default:
r = kvm_arch_vm_ioctl(filp, ioctl, arg);
}
--
1.5.4.5