Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio fixes from Michael Tsirkin:
"This includes some fixes and cleanups in virtio and vhost code.
Most notably, shadowing the index fixes the excessive cacheline
bouncing observed on AMD platforms"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio_ring: shadow available ring flags & index
virtio: Do not drop __GFP_HIGH in alloc_indirect
vhost: replace % with & on data path
tools/virtio: fix byteswap logic
tools/virtio: move list macro stubs
virtio: fix memory leak of virtio ida cache layers
vhost: relax log address alignment
virtio-net: Stop doing DMA from the stack
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index d8838ded..f94ab78 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -140,6 +140,12 @@
/* CPU hot plug notifier */
struct notifier_block nb;
+
+ /* Control VQ buffers: protected by the rtnl lock */
+ struct virtio_net_ctrl_hdr ctrl_hdr;
+ virtio_net_ctrl_ack ctrl_status;
+ u8 ctrl_promisc;
+ u8 ctrl_allmulti;
};
struct padded_vnet_hdr {
@@ -976,31 +982,30 @@
struct scatterlist *out)
{
struct scatterlist *sgs[4], hdr, stat;
- struct virtio_net_ctrl_hdr ctrl;
- virtio_net_ctrl_ack status = ~0;
unsigned out_num = 0, tmp;
/* Caller should know better */
BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
- ctrl.class = class;
- ctrl.cmd = cmd;
+ vi->ctrl_status = ~0;
+ vi->ctrl_hdr.class = class;
+ vi->ctrl_hdr.cmd = cmd;
/* Add header */
- sg_init_one(&hdr, &ctrl, sizeof(ctrl));
+ sg_init_one(&hdr, &vi->ctrl_hdr, sizeof(vi->ctrl_hdr));
sgs[out_num++] = &hdr;
if (out)
sgs[out_num++] = out;
/* Add return status. */
- sg_init_one(&stat, &status, sizeof(status));
+ sg_init_one(&stat, &vi->ctrl_status, sizeof(vi->ctrl_status));
sgs[out_num] = &stat;
BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
if (unlikely(!virtqueue_kick(vi->cvq)))
- return status == VIRTIO_NET_OK;
+ return vi->ctrl_status == VIRTIO_NET_OK;
/* Spin for a response, the kick causes an ioport write, trapping
* into the hypervisor, so the request should be handled immediately.
@@ -1009,7 +1014,7 @@
!virtqueue_is_broken(vi->cvq))
cpu_relax();
- return status == VIRTIO_NET_OK;
+ return vi->ctrl_status == VIRTIO_NET_OK;
}
static int virtnet_set_mac_address(struct net_device *dev, void *p)
@@ -1151,7 +1156,6 @@
{
struct virtnet_info *vi = netdev_priv(dev);
struct scatterlist sg[2];
- u8 promisc, allmulti;
struct virtio_net_ctrl_mac *mac_data;
struct netdev_hw_addr *ha;
int uc_count;
@@ -1163,22 +1167,22 @@
if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
return;
- promisc = ((dev->flags & IFF_PROMISC) != 0);
- allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
+ vi->ctrl_promisc = ((dev->flags & IFF_PROMISC) != 0);
+ vi->ctrl_allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
- sg_init_one(sg, &promisc, sizeof(promisc));
+ sg_init_one(sg, &vi->ctrl_promisc, sizeof(vi->ctrl_promisc));
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
VIRTIO_NET_CTRL_RX_PROMISC, sg))
dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
- promisc ? "en" : "dis");
+ vi->ctrl_promisc ? "en" : "dis");
- sg_init_one(sg, &allmulti, sizeof(allmulti));
+ sg_init_one(sg, &vi->ctrl_allmulti, sizeof(vi->ctrl_allmulti));
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
- allmulti ? "en" : "dis");
+ vi->ctrl_allmulti ? "en" : "dis");
uc_count = netdev_uc_count(dev);
mc_count = netdev_mc_count(dev);
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index eec2f11..ad2146a 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -819,7 +819,7 @@
BUILD_BUG_ON(__alignof__ *vq->used > VRING_USED_ALIGN_SIZE);
if ((a.avail_user_addr & (VRING_AVAIL_ALIGN_SIZE - 1)) ||
(a.used_user_addr & (VRING_USED_ALIGN_SIZE - 1)) ||
- (a.log_guest_addr & (sizeof(u64) - 1))) {
+ (a.log_guest_addr & (VRING_USED_ALIGN_SIZE - 1))) {
r = -EINVAL;
break;
}
@@ -1369,7 +1369,7 @@
/* Grab the next descriptor number they're advertising, and increment
* the index we've seen. */
if (unlikely(__get_user(ring_head,
- &vq->avail->ring[last_avail_idx % vq->num]))) {
+ &vq->avail->ring[last_avail_idx & (vq->num - 1)]))) {
vq_err(vq, "Failed to read head: idx %d address %p\n",
last_avail_idx,
&vq->avail->ring[last_avail_idx % vq->num]);
@@ -1489,7 +1489,7 @@
u16 old, new;
int start;
- start = vq->last_used_idx % vq->num;
+ start = vq->last_used_idx & (vq->num - 1);
used = vq->used->ring + start;
if (count == 1) {
if (__put_user(heads[0].id, &used->id)) {
@@ -1531,7 +1531,7 @@
{
int start, n, r;
- start = vq->last_used_idx % vq->num;
+ start = vq->last_used_idx & (vq->num - 1);
n = vq->num - start;
if (n < count) {
r = __vhost_add_used_n(vq, heads, n);
diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index b1877d7..7062bb0 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -412,6 +412,7 @@
static void __exit virtio_exit(void)
{
bus_unregister(&virtio_bus);
+ ida_destroy(&virtio_index_ida);
}
core_initcall(virtio_init);
module_exit(virtio_exit);
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 096b857..ee663c4 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -80,6 +80,12 @@
/* Last used index we've seen. */
u16 last_used_idx;
+ /* Last written value to avail->flags */
+ u16 avail_flags_shadow;
+
+ /* Last written value to avail->idx in guest byte order */
+ u16 avail_idx_shadow;
+
/* How to notify other side. FIXME: commonalize hcalls! */
bool (*notify)(struct virtqueue *vq);
@@ -109,7 +115,7 @@
* otherwise virt_to_phys will give us bogus addresses in the
* virtqueue.
*/
- gfp &= ~(__GFP_HIGHMEM | __GFP_HIGH);
+ gfp &= ~__GFP_HIGHMEM;
desc = kmalloc(total_sg * sizeof(struct vring_desc), gfp);
if (!desc)
@@ -235,13 +241,14 @@
/* Put entry in available array (but don't update avail->idx until they
* do sync). */
- avail = virtio16_to_cpu(_vq->vdev, vq->vring.avail->idx) & (vq->vring.num - 1);
+ avail = vq->avail_idx_shadow & (vq->vring.num - 1);
vq->vring.avail->ring[avail] = cpu_to_virtio16(_vq->vdev, head);
/* Descriptors and available array need to be set before we expose the
* new available array entries. */
virtio_wmb(vq->weak_barriers);
- vq->vring.avail->idx = cpu_to_virtio16(_vq->vdev, virtio16_to_cpu(_vq->vdev, vq->vring.avail->idx) + 1);
+ vq->avail_idx_shadow++;
+ vq->vring.avail->idx = cpu_to_virtio16(_vq->vdev, vq->avail_idx_shadow);
vq->num_added++;
pr_debug("Added buffer head %i to %p\n", head, vq);
@@ -354,8 +361,8 @@
* event. */
virtio_mb(vq->weak_barriers);
- old = virtio16_to_cpu(_vq->vdev, vq->vring.avail->idx) - vq->num_added;
- new = virtio16_to_cpu(_vq->vdev, vq->vring.avail->idx);
+ old = vq->avail_idx_shadow - vq->num_added;
+ new = vq->avail_idx_shadow;
vq->num_added = 0;
#ifdef DEBUG
@@ -510,7 +517,7 @@
/* If we expect an interrupt for the next entry, tell host
* by writing event index and flush out the write before
* the read in the next get_buf call. */
- if (!(vq->vring.avail->flags & cpu_to_virtio16(_vq->vdev, VRING_AVAIL_F_NO_INTERRUPT))) {
+ if (!(vq->avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT)) {
vring_used_event(&vq->vring) = cpu_to_virtio16(_vq->vdev, vq->last_used_idx);
virtio_mb(vq->weak_barriers);
}
@@ -537,7 +544,11 @@
{
struct vring_virtqueue *vq = to_vvq(_vq);
- vq->vring.avail->flags |= cpu_to_virtio16(_vq->vdev, VRING_AVAIL_F_NO_INTERRUPT);
+ if (!(vq->avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT)) {
+ vq->avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT;
+ vq->vring.avail->flags = cpu_to_virtio16(_vq->vdev, vq->avail_flags_shadow);
+ }
+
}
EXPORT_SYMBOL_GPL(virtqueue_disable_cb);
@@ -565,7 +576,10 @@
/* Depending on the VIRTIO_RING_F_EVENT_IDX feature, we need to
* either clear the flags bit or point the event index at the next
* entry. Always do both to keep code simple. */
- vq->vring.avail->flags &= cpu_to_virtio16(_vq->vdev, ~VRING_AVAIL_F_NO_INTERRUPT);
+ if (vq->avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT) {
+ vq->avail_flags_shadow &= ~VRING_AVAIL_F_NO_INTERRUPT;
+ vq->vring.avail->flags = cpu_to_virtio16(_vq->vdev, vq->avail_flags_shadow);
+ }
vring_used_event(&vq->vring) = cpu_to_virtio16(_vq->vdev, last_used_idx = vq->last_used_idx);
END_USE(vq);
return last_used_idx;
@@ -633,9 +647,12 @@
/* Depending on the VIRTIO_RING_F_USED_EVENT_IDX feature, we need to
* either clear the flags bit or point the event index at the next
* entry. Always do both to keep code simple. */
- vq->vring.avail->flags &= cpu_to_virtio16(_vq->vdev, ~VRING_AVAIL_F_NO_INTERRUPT);
+ if (vq->avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT) {
+ vq->avail_flags_shadow &= ~VRING_AVAIL_F_NO_INTERRUPT;
+ vq->vring.avail->flags = cpu_to_virtio16(_vq->vdev, vq->avail_flags_shadow);
+ }
/* TODO: tune this threshold */
- bufs = (u16)(virtio16_to_cpu(_vq->vdev, vq->vring.avail->idx) - vq->last_used_idx) * 3 / 4;
+ bufs = (u16)(vq->avail_idx_shadow - vq->last_used_idx) * 3 / 4;
vring_used_event(&vq->vring) = cpu_to_virtio16(_vq->vdev, vq->last_used_idx + bufs);
virtio_mb(vq->weak_barriers);
if (unlikely((u16)(virtio16_to_cpu(_vq->vdev, vq->vring.used->idx) - vq->last_used_idx) > bufs)) {
@@ -670,7 +687,8 @@
/* detach_buf clears data, so grab it now. */
buf = vq->data[i];
detach_buf(vq, i);
- vq->vring.avail->idx = cpu_to_virtio16(_vq->vdev, virtio16_to_cpu(_vq->vdev, vq->vring.avail->idx) - 1);
+ vq->avail_idx_shadow--;
+ vq->vring.avail->idx = cpu_to_virtio16(_vq->vdev, vq->avail_idx_shadow);
END_USE(vq);
return buf;
}
@@ -735,6 +753,8 @@
vq->weak_barriers = weak_barriers;
vq->broken = false;
vq->last_used_idx = 0;
+ vq->avail_flags_shadow = 0;
+ vq->avail_idx_shadow = 0;
vq->num_added = 0;
list_add_tail(&vq->vq.list, &vdev->vqs);
#ifdef DEBUG
@@ -746,8 +766,10 @@
vq->event = virtio_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX);
/* No callback? Tell other side not to bother us. */
- if (!callback)
- vq->vring.avail->flags |= cpu_to_virtio16(vdev, VRING_AVAIL_F_NO_INTERRUPT);
+ if (!callback) {
+ vq->avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT;
+ vq->vring.avail->flags = cpu_to_virtio16(vdev, vq->avail_flags_shadow);
+ }
/* Put everything in free lists. */
vq->free_head = 0;
diff --git a/tools/virtio/linux/kernel.h b/tools/virtio/linux/kernel.h
index 0a3da64..4db7d56 100644
--- a/tools/virtio/linux/kernel.h
+++ b/tools/virtio/linux/kernel.h
@@ -110,4 +110,10 @@
(void) (&_min1 == &_min2); \
_min1 < _min2 ? _min1 : _min2; })
+/* TODO: empty stubs for now. Broken but enough for virtio_ring.c */
+#define list_add_tail(a, b) do {} while (0)
+#define list_del(a) do {} while (0)
+#define list_for_each_entry(a, b, c) while (0)
+/* end of stubs */
+
#endif /* KERNEL_H */
diff --git a/tools/virtio/linux/virtio.h b/tools/virtio/linux/virtio.h
index a3e0701..ee125e7 100644
--- a/tools/virtio/linux/virtio.h
+++ b/tools/virtio/linux/virtio.h
@@ -3,12 +3,6 @@
#include <linux/scatterlist.h>
#include <linux/kernel.h>
-/* TODO: empty stubs for now. Broken but enough for virtio_ring.c */
-#define list_add_tail(a, b) do {} while (0)
-#define list_del(a) do {} while (0)
-#define list_for_each_entry(a, b, c) while (0)
-/* end of stubs */
-
struct virtio_device {
void *dev;
u64 features;
diff --git a/tools/virtio/linux/virtio_config.h b/tools/virtio/linux/virtio_config.h
index 806d683..57a6964 100644
--- a/tools/virtio/linux/virtio_config.h
+++ b/tools/virtio/linux/virtio_config.h
@@ -40,33 +40,39 @@
#define virtio_has_feature(dev, feature) \
(__virtio_test_bit((dev), feature))
+static inline bool virtio_is_little_endian(struct virtio_device *vdev)
+{
+ return virtio_has_feature(vdev, VIRTIO_F_VERSION_1) ||
+ virtio_legacy_is_little_endian();
+}
+
+/* Memory accessors */
static inline u16 virtio16_to_cpu(struct virtio_device *vdev, __virtio16 val)
{
- return __virtio16_to_cpu(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
+ return __virtio16_to_cpu(virtio_is_little_endian(vdev), val);
}
static inline __virtio16 cpu_to_virtio16(struct virtio_device *vdev, u16 val)
{
- return __cpu_to_virtio16(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
+ return __cpu_to_virtio16(virtio_is_little_endian(vdev), val);
}
static inline u32 virtio32_to_cpu(struct virtio_device *vdev, __virtio32 val)
{
- return __virtio32_to_cpu(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
+ return __virtio32_to_cpu(virtio_is_little_endian(vdev), val);
}
static inline __virtio32 cpu_to_virtio32(struct virtio_device *vdev, u32 val)
{
- return __cpu_to_virtio32(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
+ return __cpu_to_virtio32(virtio_is_little_endian(vdev), val);
}
static inline u64 virtio64_to_cpu(struct virtio_device *vdev, __virtio64 val)
{
- return __virtio64_to_cpu(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
+ return __virtio64_to_cpu(virtio_is_little_endian(vdev), val);
}
static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val)
{
- return __cpu_to_virtio64(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
+ return __cpu_to_virtio64(virtio_is_little_endian(vdev), val);
}
-