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-rw-r--r--drivers/vhost/net.c64
-rw-r--r--drivers/vhost/scsi.c8
-rw-r--r--drivers/vhost/vhost.c23
3 files changed, 79 insertions, 16 deletions
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index ab11b2bee273..36f3d0f49e60 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -141,6 +141,10 @@ struct vhost_net {
unsigned tx_zcopy_err;
/* Flush in progress. Protected by tx vq lock. */
bool tx_flush;
+ /* Private page frag */
+ struct page_frag page_frag;
+ /* Refcount bias of page frag */
+ int refcnt_bias;
};
static unsigned vhost_net_zcopy_mask __read_mostly;
@@ -513,7 +517,13 @@ static void vhost_net_busy_poll(struct vhost_net *net,
struct socket *sock;
struct vhost_virtqueue *vq = poll_rx ? tvq : rvq;
- mutex_lock_nested(&vq->mutex, poll_rx ? VHOST_NET_VQ_TX: VHOST_NET_VQ_RX);
+ /* Try to hold the vq mutex of the paired virtqueue. We can't
+ * use mutex_lock() here since we could not guarantee a
+ * consistenet lock ordering.
+ */
+ if (!mutex_trylock(&vq->mutex))
+ return;
+
vhost_disable_notify(&net->dev, vq);
sock = rvq->private_data;
@@ -637,14 +647,53 @@ static bool tx_can_batch(struct vhost_virtqueue *vq, size_t total_len)
!vhost_vq_avail_empty(vq->dev, vq);
}
+#define SKB_FRAG_PAGE_ORDER get_order(32768)
+
+static bool vhost_net_page_frag_refill(struct vhost_net *net, unsigned int sz,
+ struct page_frag *pfrag, gfp_t gfp)
+{
+ if (pfrag->page) {
+ if (pfrag->offset + sz <= pfrag->size)
+ return true;
+ __page_frag_cache_drain(pfrag->page, net->refcnt_bias);
+ }
+
+ pfrag->offset = 0;
+ net->refcnt_bias = 0;
+ if (SKB_FRAG_PAGE_ORDER) {
+ /* Avoid direct reclaim but allow kswapd to wake */
+ pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
+ __GFP_COMP | __GFP_NOWARN |
+ __GFP_NORETRY,
+ SKB_FRAG_PAGE_ORDER);
+ if (likely(pfrag->page)) {
+ pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
+ goto done;
+ }
+ }
+ pfrag->page = alloc_page(gfp);
+ if (likely(pfrag->page)) {
+ pfrag->size = PAGE_SIZE;
+ goto done;
+ }
+ return false;
+
+done:
+ net->refcnt_bias = USHRT_MAX;
+ page_ref_add(pfrag->page, USHRT_MAX - 1);
+ return true;
+}
+
#define VHOST_NET_RX_PAD (NET_IP_ALIGN + NET_SKB_PAD)
static int vhost_net_build_xdp(struct vhost_net_virtqueue *nvq,
struct iov_iter *from)
{
struct vhost_virtqueue *vq = &nvq->vq;
+ struct vhost_net *net = container_of(vq->dev, struct vhost_net,
+ dev);
struct socket *sock = vq->private_data;
- struct page_frag *alloc_frag = &current->task_frag;
+ struct page_frag *alloc_frag = &net->page_frag;
struct virtio_net_hdr *gso;
struct xdp_buff *xdp = &nvq->xdp[nvq->batched_xdp];
struct tun_xdp_hdr *hdr;
@@ -665,7 +714,8 @@ static int vhost_net_build_xdp(struct vhost_net_virtqueue *nvq,
buflen += SKB_DATA_ALIGN(len + pad);
alloc_frag->offset = ALIGN((u64)alloc_frag->offset, SMP_CACHE_BYTES);
- if (unlikely(!skb_page_frag_refill(buflen, alloc_frag, GFP_KERNEL)))
+ if (unlikely(!vhost_net_page_frag_refill(net, buflen,
+ alloc_frag, GFP_KERNEL)))
return -ENOMEM;
buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
@@ -703,7 +753,7 @@ static int vhost_net_build_xdp(struct vhost_net_virtqueue *nvq,
xdp->data_end = xdp->data + len;
hdr->buflen = buflen;
- get_page(alloc_frag->page);
+ --net->refcnt_bias;
alloc_frag->offset += buflen;
++nvq->batched_xdp;
@@ -1292,6 +1342,8 @@ static int vhost_net_open(struct inode *inode, struct file *f)
vhost_poll_init(n->poll + VHOST_NET_VQ_RX, handle_rx_net, EPOLLIN, dev);
f->private_data = n;
+ n->page_frag.page = NULL;
+ n->refcnt_bias = 0;
return 0;
}
@@ -1359,13 +1411,15 @@ static int vhost_net_release(struct inode *inode, struct file *f)
if (rx_sock)
sockfd_put(rx_sock);
/* Make sure no callbacks are outstanding */
- synchronize_rcu_bh();
+ synchronize_rcu();
/* We do an extra flush before freeing memory,
* since jobs can re-queue themselves. */
vhost_net_flush(n);
kfree(n->vqs[VHOST_NET_VQ_RX].rxq.queue);
kfree(n->vqs[VHOST_NET_VQ_TX].xdp);
kfree(n->dev.vqs);
+ if (n->page_frag.page)
+ __page_frag_cache_drain(n->page_frag.page, n->refcnt_bias);
kvfree(n);
return 0;
}
diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
index 50dffe83714c..a08472ae5b1b 100644
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -285,11 +285,6 @@ static int vhost_scsi_check_false(struct se_portal_group *se_tpg)
return 0;
}
-static char *vhost_scsi_get_fabric_name(void)
-{
- return "vhost";
-}
-
static char *vhost_scsi_get_fabric_wwn(struct se_portal_group *se_tpg)
{
struct vhost_scsi_tpg *tpg = container_of(se_tpg,
@@ -2289,8 +2284,7 @@ static struct configfs_attribute *vhost_scsi_wwn_attrs[] = {
static const struct target_core_fabric_ops vhost_scsi_ops = {
.module = THIS_MODULE,
- .name = "vhost",
- .get_fabric_name = vhost_scsi_get_fabric_name,
+ .fabric_name = "vhost",
.tpg_get_wwn = vhost_scsi_get_fabric_wwn,
.tpg_get_tag = vhost_scsi_get_tpgt,
.tpg_check_demo_mode = vhost_scsi_check_true,
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 6b98d8e3a5bf..55e5aa662ad5 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -295,11 +295,8 @@ static void vhost_vq_meta_reset(struct vhost_dev *d)
{
int i;
- for (i = 0; i < d->nvqs; ++i) {
- mutex_lock(&d->vqs[i]->mutex);
+ for (i = 0; i < d->nvqs; ++i)
__vhost_vq_meta_reset(d->vqs[i]);
- mutex_unlock(&d->vqs[i]->mutex);
- }
}
static void vhost_vq_reset(struct vhost_dev *dev,
@@ -895,6 +892,20 @@ static inline void __user *__vhost_get_user(struct vhost_virtqueue *vq,
#define vhost_get_used(vq, x, ptr) \
vhost_get_user(vq, x, ptr, VHOST_ADDR_USED)
+static void vhost_dev_lock_vqs(struct vhost_dev *d)
+{
+ int i = 0;
+ for (i = 0; i < d->nvqs; ++i)
+ mutex_lock_nested(&d->vqs[i]->mutex, i);
+}
+
+static void vhost_dev_unlock_vqs(struct vhost_dev *d)
+{
+ int i = 0;
+ for (i = 0; i < d->nvqs; ++i)
+ mutex_unlock(&d->vqs[i]->mutex);
+}
+
static int vhost_new_umem_range(struct vhost_umem *umem,
u64 start, u64 size, u64 end,
u64 userspace_addr, int perm)
@@ -976,6 +987,7 @@ static int vhost_process_iotlb_msg(struct vhost_dev *dev,
int ret = 0;
mutex_lock(&dev->mutex);
+ vhost_dev_lock_vqs(dev);
switch (msg->type) {
case VHOST_IOTLB_UPDATE:
if (!dev->iotlb) {
@@ -1009,6 +1021,7 @@ static int vhost_process_iotlb_msg(struct vhost_dev *dev,
break;
}
+ vhost_dev_unlock_vqs(dev);
mutex_unlock(&dev->mutex);
return ret;
@@ -2220,6 +2233,8 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads,
return -EFAULT;
}
if (unlikely(vq->log_used)) {
+ /* Make sure used idx is seen before log. */
+ smp_wmb();
/* Log used index update. */
log_write(vq->log_base,
vq->log_addr + offsetof(struct vring_used, idx),
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