#include "iodev.h"
#include <linux/kvm_host.h>
+#include <linux/slab.h>
#include <linux/kvm.h>
#include "coalesced_mmio.h"
-static int coalesced_mmio_in_range(struct kvm_io_device *this,
- gpa_t addr, int len, int is_write)
+static inline struct kvm_coalesced_mmio_dev *to_mmio(struct kvm_io_device *dev)
+{
+ return container_of(dev, struct kvm_coalesced_mmio_dev, dev);
+}
+
+static int coalesced_mmio_in_range(struct kvm_coalesced_mmio_dev *dev,
+ gpa_t addr, int len)
{
- struct kvm_coalesced_mmio_dev *dev =
- (struct kvm_coalesced_mmio_dev*)this->private;
struct kvm_coalesced_mmio_zone *zone;
- int next;
+ struct kvm_coalesced_mmio_ring *ring;
+ unsigned avail;
int i;
- if (!is_write)
- return 0;
-
- /* kvm->lock is taken by the caller and must be not released before
- * dev.read/write
- */
-
/* Are we able to batch it ? */
/* last is the first free entry
* check if we don't meet the first used entry
* there is always one unused entry in the buffer
*/
-
- next = (dev->kvm->coalesced_mmio_ring->last + 1) %
- KVM_COALESCED_MMIO_MAX;
- if (next == dev->kvm->coalesced_mmio_ring->first) {
+ ring = dev->kvm->coalesced_mmio_ring;
+ avail = (ring->first - ring->last - 1) % KVM_COALESCED_MMIO_MAX;
+ if (avail < KVM_MAX_VCPUS) {
/* full */
return 0;
}
return 0;
}
-static void coalesced_mmio_write(struct kvm_io_device *this,
- gpa_t addr, int len, const void *val)
+static int coalesced_mmio_write(struct kvm_io_device *this,
+ gpa_t addr, int len, const void *val)
{
- struct kvm_coalesced_mmio_dev *dev =
- (struct kvm_coalesced_mmio_dev*)this->private;
+ struct kvm_coalesced_mmio_dev *dev = to_mmio(this);
struct kvm_coalesced_mmio_ring *ring = dev->kvm->coalesced_mmio_ring;
+ if (!coalesced_mmio_in_range(dev, addr, len))
+ return -EOPNOTSUPP;
- /* kvm->lock must be taken by caller before call to in_range()*/
+ spin_lock(&dev->lock);
/* copy data in first free entry of the ring */
memcpy(ring->coalesced_mmio[ring->last].data, val, len);
smp_wmb();
ring->last = (ring->last + 1) % KVM_COALESCED_MMIO_MAX;
+ spin_unlock(&dev->lock);
+ return 0;
}
static void coalesced_mmio_destructor(struct kvm_io_device *this)
{
- kfree(this);
+ struct kvm_coalesced_mmio_dev *dev = to_mmio(this);
+
+ kfree(dev);
}
+static const struct kvm_io_device_ops coalesced_mmio_ops = {
+ .write = coalesced_mmio_write,
+ .destructor = coalesced_mmio_destructor,
+};
+
int kvm_coalesced_mmio_init(struct kvm *kvm)
{
struct kvm_coalesced_mmio_dev *dev;
+ struct page *page;
+ int ret;
+
+ ret = -ENOMEM;
+ page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+ if (!page)
+ goto out_err;
+ kvm->coalesced_mmio_ring = page_address(page);
+ ret = -ENOMEM;
dev = kzalloc(sizeof(struct kvm_coalesced_mmio_dev), GFP_KERNEL);
if (!dev)
- return -ENOMEM;
- dev->dev.write = coalesced_mmio_write;
- dev->dev.in_range = coalesced_mmio_in_range;
- dev->dev.destructor = coalesced_mmio_destructor;
- dev->dev.private = dev;
+ goto out_free_page;
+ spin_lock_init(&dev->lock);
+ kvm_iodevice_init(&dev->dev, &coalesced_mmio_ops);
dev->kvm = kvm;
kvm->coalesced_mmio_dev = dev;
- kvm_io_bus_register_dev(&kvm->mmio_bus, &dev->dev);
- return 0;
+ mutex_lock(&kvm->slots_lock);
+ ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, &dev->dev);
+ mutex_unlock(&kvm->slots_lock);
+ if (ret < 0)
+ goto out_free_dev;
+
+ return ret;
+
+out_free_dev:
+ kfree(dev);
+out_free_page:
+ __free_page(page);
+out_err:
+ return ret;
+}
+
+void kvm_coalesced_mmio_free(struct kvm *kvm)
+{
+ if (kvm->coalesced_mmio_ring)
+ free_page((unsigned long)kvm->coalesced_mmio_ring);
}
int kvm_vm_ioctl_register_coalesced_mmio(struct kvm *kvm,
- struct kvm_coalesced_mmio_zone *zone)
+ struct kvm_coalesced_mmio_zone *zone)
{
struct kvm_coalesced_mmio_dev *dev = kvm->coalesced_mmio_dev;
if (dev == NULL)
return -EINVAL;
- mutex_lock(&kvm->lock);
+ mutex_lock(&kvm->slots_lock);
if (dev->nb_zones >= KVM_COALESCED_MMIO_ZONE_MAX) {
- mutex_unlock(&kvm->lock);
+ mutex_unlock(&kvm->slots_lock);
return -ENOBUFS;
}
dev->zone[dev->nb_zones] = *zone;
dev->nb_zones++;
- mutex_unlock(&kvm->lock);
+ mutex_unlock(&kvm->slots_lock);
return 0;
}
if (dev == NULL)
return -EINVAL;
- mutex_lock(&kvm->lock);
+ mutex_lock(&kvm->slots_lock);
i = dev->nb_zones;
- while(i) {
+ while (i) {
z = &dev->zone[i - 1];
/* unregister all zones
i--;
}
- mutex_unlock(&kvm->lock);
+ mutex_unlock(&kvm->slots_lock);
return 0;
}