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authorMarcel Ziswiler <marcel.ziswiler@toradex.com>2020-05-21 00:54:36 +0200
committerMarcel Ziswiler <marcel.ziswiler@toradex.com>2020-05-21 00:54:36 +0200
commit135d39dcedcedd1f44ea0bba52f15ac5922c114f (patch)
tree12379fc8ef7489eaca1c7245f8bd6af74c619a8f /virt/kvm/coalesced_mmio.c
parent187764bd111b27783b6d68ffb3b3dbb3a9bafd38 (diff)
parent1279cd128bba968ebe0a2df7f7ae38bae90250ef (diff)
Merge remote-tracking branch 'remotes/fslc/4.9-2.3.x-imx' into toradex_4.9-2.3.x-imx-next
Conflicts: sound/soc/codecs/sgtl5000.c sound/soc/fsl/imx-sgtl5000.c
Diffstat (limited to 'virt/kvm/coalesced_mmio.c')
-rw-r--r--virt/kvm/coalesced_mmio.c17
1 files changed, 10 insertions, 7 deletions
diff --git a/virt/kvm/coalesced_mmio.c b/virt/kvm/coalesced_mmio.c
index 571c1ce37d15..5c1efb869df2 100644
--- a/virt/kvm/coalesced_mmio.c
+++ b/virt/kvm/coalesced_mmio.c
@@ -39,7 +39,7 @@ static int coalesced_mmio_in_range(struct kvm_coalesced_mmio_dev *dev,
return 1;
}
-static int coalesced_mmio_has_room(struct kvm_coalesced_mmio_dev *dev)
+static int coalesced_mmio_has_room(struct kvm_coalesced_mmio_dev *dev, u32 last)
{
struct kvm_coalesced_mmio_ring *ring;
unsigned avail;
@@ -51,7 +51,7 @@ static int coalesced_mmio_has_room(struct kvm_coalesced_mmio_dev *dev)
* there is always one unused entry in the buffer
*/
ring = dev->kvm->coalesced_mmio_ring;
- avail = (ring->first - ring->last - 1) % KVM_COALESCED_MMIO_MAX;
+ avail = (ring->first - last - 1) % KVM_COALESCED_MMIO_MAX;
if (avail == 0) {
/* full */
return 0;
@@ -66,24 +66,27 @@ static int coalesced_mmio_write(struct kvm_vcpu *vcpu,
{
struct kvm_coalesced_mmio_dev *dev = to_mmio(this);
struct kvm_coalesced_mmio_ring *ring = dev->kvm->coalesced_mmio_ring;
+ __u32 insert;
if (!coalesced_mmio_in_range(dev, addr, len))
return -EOPNOTSUPP;
spin_lock(&dev->kvm->ring_lock);
- if (!coalesced_mmio_has_room(dev)) {
+ insert = READ_ONCE(ring->last);
+ if (!coalesced_mmio_has_room(dev, insert) ||
+ insert >= KVM_COALESCED_MMIO_MAX) {
spin_unlock(&dev->kvm->ring_lock);
return -EOPNOTSUPP;
}
/* copy data in first free entry of the ring */
- ring->coalesced_mmio[ring->last].phys_addr = addr;
- ring->coalesced_mmio[ring->last].len = len;
- memcpy(ring->coalesced_mmio[ring->last].data, val, len);
+ ring->coalesced_mmio[insert].phys_addr = addr;
+ ring->coalesced_mmio[insert].len = len;
+ memcpy(ring->coalesced_mmio[insert].data, val, len);
smp_wmb();
- ring->last = (ring->last + 1) % KVM_COALESCED_MMIO_MAX;
+ ring->last = (insert + 1) % KVM_COALESCED_MMIO_MAX;
spin_unlock(&dev->kvm->ring_lock);
return 0;
}