vhost: move vhost-net zerocopy fields to net.c

On top of 'vhost: Allow device specific fields per vq', we can move device
specific fields to device virt queue from vhost virt queue.

Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Asias He 2013-04-27 15:07:46 +08:00 committed by Michael S. Tsirkin
parent f2f0173d6a
commit 2839400f8f
3 changed files with 142 additions and 101 deletions

View file

@ -64,8 +64,24 @@ enum {
VHOST_NET_VQ_MAX = 2,
};
struct vhost_ubuf_ref {
struct kref kref;
wait_queue_head_t wait;
struct vhost_virtqueue *vq;
};
struct vhost_net_virtqueue {
struct vhost_virtqueue vq;
/* vhost zerocopy support fields below: */
/* last used idx for outstanding DMA zerocopy buffers */
int upend_idx;
/* first used idx for DMA done zerocopy buffers */
int done_idx;
/* an array of userspace buffers info */
struct ubuf_info *ubuf_info;
/* Reference counting for outstanding ubufs.
* Protected by vq mutex. Writers must also take device mutex. */
struct vhost_ubuf_ref *ubufs;
};
struct vhost_net {
@ -82,6 +98,88 @@ struct vhost_net {
bool tx_flush;
};
static unsigned vhost_zcopy_mask __read_mostly;
void vhost_enable_zcopy(int vq)
{
vhost_zcopy_mask |= 0x1 << vq;
}
static void vhost_zerocopy_done_signal(struct kref *kref)
{
struct vhost_ubuf_ref *ubufs = container_of(kref, struct vhost_ubuf_ref,
kref);
wake_up(&ubufs->wait);
}
struct vhost_ubuf_ref *vhost_ubuf_alloc(struct vhost_virtqueue *vq,
bool zcopy)
{
struct vhost_ubuf_ref *ubufs;
/* No zero copy backend? Nothing to count. */
if (!zcopy)
return NULL;
ubufs = kmalloc(sizeof(*ubufs), GFP_KERNEL);
if (!ubufs)
return ERR_PTR(-ENOMEM);
kref_init(&ubufs->kref);
init_waitqueue_head(&ubufs->wait);
ubufs->vq = vq;
return ubufs;
}
void vhost_ubuf_put(struct vhost_ubuf_ref *ubufs)
{
kref_put(&ubufs->kref, vhost_zerocopy_done_signal);
}
void vhost_ubuf_put_and_wait(struct vhost_ubuf_ref *ubufs)
{
kref_put(&ubufs->kref, vhost_zerocopy_done_signal);
wait_event(ubufs->wait, !atomic_read(&ubufs->kref.refcount));
kfree(ubufs);
}
int vhost_net_set_ubuf_info(struct vhost_net *n)
{
bool zcopy;
int i;
for (i = 0; i < n->dev.nvqs; ++i) {
zcopy = vhost_zcopy_mask & (0x1 << i);
if (!zcopy)
continue;
n->vqs[i].ubuf_info = kmalloc(sizeof(*n->vqs[i].ubuf_info) *
UIO_MAXIOV, GFP_KERNEL);
if (!n->vqs[i].ubuf_info)
goto err;
}
return 0;
err:
while (i--) {
zcopy = vhost_zcopy_mask & (0x1 << i);
if (!zcopy)
continue;
kfree(n->vqs[i].ubuf_info);
}
return -ENOMEM;
}
void vhost_net_reset_ubuf_info(struct vhost_net *n)
{
int i;
for (i = 0; i < VHOST_NET_VQ_MAX; i++) {
n->vqs[i].done_idx = 0;
n->vqs[i].upend_idx = 0;
n->vqs[i].ubufs = NULL;
kfree(n->vqs[i].ubuf_info);
n->vqs[i].ubuf_info = NULL;
}
}
static void vhost_net_tx_packet(struct vhost_net *net)
{
++net->tx_packets;
@ -157,10 +255,12 @@ static void copy_iovec_hdr(const struct iovec *from, struct iovec *to,
static int vhost_zerocopy_signal_used(struct vhost_net *net,
struct vhost_virtqueue *vq)
{
struct vhost_net_virtqueue *nvq =
container_of(vq, struct vhost_net_virtqueue, vq);
int i;
int j = 0;
for (i = vq->done_idx; i != vq->upend_idx; i = (i + 1) % UIO_MAXIOV) {
for (i = nvq->done_idx; i != nvq->upend_idx; i = (i + 1) % UIO_MAXIOV) {
if (vq->heads[i].len == VHOST_DMA_FAILED_LEN)
vhost_net_tx_err(net);
if (VHOST_DMA_IS_DONE(vq->heads[i].len)) {
@ -172,7 +272,7 @@ static int vhost_zerocopy_signal_used(struct vhost_net *net,
break;
}
if (j)
vq->done_idx = i;
nvq->done_idx = i;
return j;
}
@ -203,6 +303,7 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success)
static void handle_tx(struct vhost_net *net)
{
struct vhost_virtqueue *vq = &net->vqs[VHOST_NET_VQ_TX].vq;
struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_TX];
unsigned out, in, s;
int head;
struct msghdr msg = {
@ -229,7 +330,7 @@ static void handle_tx(struct vhost_net *net)
vhost_disable_notify(&net->dev, vq);
hdr_size = vq->vhost_hlen;
zcopy = vq->ubufs;
zcopy = nvq->ubufs;
for (;;) {
/* Release DMAs done buffers first */
@ -250,9 +351,10 @@ static void handle_tx(struct vhost_net *net)
/* If more outstanding DMAs, queue the work.
* Handle upend_idx wrap around
*/
num_pends = likely(vq->upend_idx >= vq->done_idx) ?
(vq->upend_idx - vq->done_idx) :
(vq->upend_idx + UIO_MAXIOV - vq->done_idx);
num_pends = likely(nvq->upend_idx >= nvq->done_idx) ?
(nvq->upend_idx - nvq->done_idx) :
(nvq->upend_idx + UIO_MAXIOV -
nvq->done_idx);
if (unlikely(num_pends > VHOST_MAX_PEND))
break;
if (unlikely(vhost_enable_notify(&net->dev, vq))) {
@ -278,34 +380,34 @@ static void handle_tx(struct vhost_net *net)
break;
}
zcopy_used = zcopy && (len >= VHOST_GOODCOPY_LEN ||
vq->upend_idx != vq->done_idx);
nvq->upend_idx != nvq->done_idx);
/* use msg_control to pass vhost zerocopy ubuf info to skb */
if (zcopy_used) {
vq->heads[vq->upend_idx].id = head;
vq->heads[nvq->upend_idx].id = head;
if (!vhost_net_tx_select_zcopy(net) ||
len < VHOST_GOODCOPY_LEN) {
/* copy don't need to wait for DMA done */
vq->heads[vq->upend_idx].len =
vq->heads[nvq->upend_idx].len =
VHOST_DMA_DONE_LEN;
msg.msg_control = NULL;
msg.msg_controllen = 0;
ubufs = NULL;
} else {
struct ubuf_info *ubuf;
ubuf = vq->ubuf_info + vq->upend_idx;
ubuf = nvq->ubuf_info + nvq->upend_idx;
vq->heads[vq->upend_idx].len =
vq->heads[nvq->upend_idx].len =
VHOST_DMA_IN_PROGRESS;
ubuf->callback = vhost_zerocopy_callback;
ubuf->ctx = vq->ubufs;
ubuf->desc = vq->upend_idx;
ubuf->ctx = nvq->ubufs;
ubuf->desc = nvq->upend_idx;
msg.msg_control = ubuf;
msg.msg_controllen = sizeof(ubuf);
ubufs = vq->ubufs;
ubufs = nvq->ubufs;
kref_get(&ubufs->kref);
}
vq->upend_idx = (vq->upend_idx + 1) % UIO_MAXIOV;
nvq->upend_idx = (nvq->upend_idx + 1) % UIO_MAXIOV;
}
/* TODO: Check specific error and bomb out unless ENOBUFS? */
err = sock->ops->sendmsg(NULL, sock, &msg, len);
@ -313,8 +415,8 @@ static void handle_tx(struct vhost_net *net)
if (zcopy_used) {
if (ubufs)
vhost_ubuf_put(ubufs);
vq->upend_idx = ((unsigned)vq->upend_idx - 1) %
UIO_MAXIOV;
nvq->upend_idx = ((unsigned)nvq->upend_idx - 1)
% UIO_MAXIOV;
}
vhost_discard_vq_desc(vq, 1);
break;
@ -564,7 +666,7 @@ static int vhost_net_open(struct inode *inode, struct file *f)
struct vhost_net *n = kmalloc(sizeof *n, GFP_KERNEL);
struct vhost_dev *dev;
struct vhost_virtqueue **vqs;
int r;
int r, i;
if (!n)
return -ENOMEM;
@ -579,6 +681,12 @@ static int vhost_net_open(struct inode *inode, struct file *f)
vqs[VHOST_NET_VQ_RX] = &n->vqs[VHOST_NET_VQ_RX].vq;
n->vqs[VHOST_NET_VQ_TX].vq.handle_kick = handle_tx_kick;
n->vqs[VHOST_NET_VQ_RX].vq.handle_kick = handle_rx_kick;
for (i = 0; i < VHOST_NET_VQ_MAX; i++) {
n->vqs[i].ubufs = NULL;
n->vqs[i].ubuf_info = NULL;
n->vqs[i].upend_idx = 0;
n->vqs[i].done_idx = 0;
}
r = vhost_dev_init(dev, vqs, VHOST_NET_VQ_MAX);
if (r < 0) {
kfree(n);
@ -652,15 +760,15 @@ static void vhost_net_flush(struct vhost_net *n)
{
vhost_net_flush_vq(n, VHOST_NET_VQ_TX);
vhost_net_flush_vq(n, VHOST_NET_VQ_RX);
if (n->vqs[VHOST_NET_VQ_TX].vq.ubufs) {
if (n->vqs[VHOST_NET_VQ_TX].ubufs) {
mutex_lock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex);
n->tx_flush = true;
mutex_unlock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex);
/* Wait for all lower device DMAs done. */
vhost_ubuf_put_and_wait(n->vqs[VHOST_NET_VQ_TX].vq.ubufs);
vhost_ubuf_put_and_wait(n->vqs[VHOST_NET_VQ_TX].ubufs);
mutex_lock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex);
n->tx_flush = false;
kref_init(&n->vqs[VHOST_NET_VQ_TX].vq.ubufs->kref);
kref_init(&n->vqs[VHOST_NET_VQ_TX].ubufs->kref);
mutex_unlock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex);
}
}
@ -675,6 +783,7 @@ static int vhost_net_release(struct inode *inode, struct file *f)
vhost_net_flush(n);
vhost_dev_stop(&n->dev);
vhost_dev_cleanup(&n->dev, false);
vhost_net_reset_ubuf_info(n);
if (tx_sock)
fput(tx_sock->file);
if (rx_sock)
@ -756,6 +865,7 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd)
{
struct socket *sock, *oldsock;
struct vhost_virtqueue *vq;
struct vhost_net_virtqueue *nvq;
struct vhost_ubuf_ref *ubufs, *oldubufs = NULL;
int r;
@ -769,6 +879,7 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd)
goto err;
}
vq = &n->vqs[index].vq;
nvq = &n->vqs[index];
mutex_lock(&vq->mutex);
/* Verify that ring has been setup correctly. */
@ -801,8 +912,8 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd)
if (r)
goto err_used;
oldubufs = vq->ubufs;
vq->ubufs = ubufs;
oldubufs = nvq->ubufs;
nvq->ubufs = ubufs;
n->tx_packets = 0;
n->tx_zcopy_err = 0;
@ -853,6 +964,7 @@ static long vhost_net_reset_owner(struct vhost_net *n)
vhost_net_stop(n, &tx_sock, &rx_sock);
vhost_net_flush(n);
err = vhost_dev_reset_owner(&n->dev);
vhost_net_reset_ubuf_info(n);
done:
mutex_unlock(&n->dev.mutex);
if (tx_sock)
@ -928,11 +1040,17 @@ static long vhost_net_ioctl(struct file *f, unsigned int ioctl,
return vhost_net_reset_owner(n);
default:
mutex_lock(&n->dev.mutex);
if (ioctl == VHOST_SET_OWNER) {
r = vhost_net_set_ubuf_info(n);
if (r)
goto out;
}
r = vhost_dev_ioctl(&n->dev, ioctl, argp);
if (r == -ENOIOCTLCMD)
r = vhost_vring_ioctl(&n->dev, ioctl, argp);
else
vhost_net_flush(n);
out:
mutex_unlock(&n->dev.mutex);
return r;
}

View file

@ -33,8 +33,6 @@ enum {
VHOST_MEMORY_F_LOG = 0x1,
};
static unsigned vhost_zcopy_mask __read_mostly;
#define vhost_used_event(vq) ((u16 __user *)&vq->avail->ring[vq->num])
#define vhost_avail_event(vq) ((u16 __user *)&vq->used->ring[vq->num])
@ -191,9 +189,6 @@ static void vhost_vq_reset(struct vhost_dev *dev,
vq->call_ctx = NULL;
vq->call = NULL;
vq->log_ctx = NULL;
vq->upend_idx = 0;
vq->done_idx = 0;
vq->ubufs = NULL;
}
static int vhost_worker(void *data)
@ -253,20 +248,12 @@ static void vhost_vq_free_iovecs(struct vhost_virtqueue *vq)
vq->log = NULL;
kfree(vq->heads);
vq->heads = NULL;
kfree(vq->ubuf_info);
vq->ubuf_info = NULL;
}
void vhost_enable_zcopy(int vq)
{
vhost_zcopy_mask |= 0x1 << vq;
}
/* Helper to allocate iovec buffers for all vqs. */
static long vhost_dev_alloc_iovecs(struct vhost_dev *dev)
{
int i;
bool zcopy;
for (i = 0; i < dev->nvqs; ++i) {
dev->vqs[i]->indirect = kmalloc(sizeof *dev->vqs[i]->indirect *
@ -275,14 +262,8 @@ static long vhost_dev_alloc_iovecs(struct vhost_dev *dev)
GFP_KERNEL);
dev->vqs[i]->heads = kmalloc(sizeof *dev->vqs[i]->heads *
UIO_MAXIOV, GFP_KERNEL);
zcopy = vhost_zcopy_mask & (0x1 << i);
if (zcopy)
dev->vqs[i]->ubuf_info =
kmalloc(sizeof *dev->vqs[i]->ubuf_info *
UIO_MAXIOV, GFP_KERNEL);
if (!dev->vqs[i]->indirect || !dev->vqs[i]->log ||
!dev->vqs[i]->heads ||
(zcopy && !dev->vqs[i]->ubuf_info))
!dev->vqs[i]->heads)
goto err_nomem;
}
return 0;
@ -321,7 +302,6 @@ long vhost_dev_init(struct vhost_dev *dev,
dev->vqs[i]->log = NULL;
dev->vqs[i]->indirect = NULL;
dev->vqs[i]->heads = NULL;
dev->vqs[i]->ubuf_info = NULL;
dev->vqs[i]->dev = dev;
mutex_init(&dev->vqs[i]->mutex);
vhost_vq_reset(dev, dev->vqs[i]);
@ -1551,38 +1531,3 @@ void vhost_disable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
&vq->used->flags, r);
}
}
static void vhost_zerocopy_done_signal(struct kref *kref)
{
struct vhost_ubuf_ref *ubufs = container_of(kref, struct vhost_ubuf_ref,
kref);
wake_up(&ubufs->wait);
}
struct vhost_ubuf_ref *vhost_ubuf_alloc(struct vhost_virtqueue *vq,
bool zcopy)
{
struct vhost_ubuf_ref *ubufs;
/* No zero copy backend? Nothing to count. */
if (!zcopy)
return NULL;
ubufs = kmalloc(sizeof *ubufs, GFP_KERNEL);
if (!ubufs)
return ERR_PTR(-ENOMEM);
kref_init(&ubufs->kref);
init_waitqueue_head(&ubufs->wait);
ubufs->vq = vq;
return ubufs;
}
void vhost_ubuf_put(struct vhost_ubuf_ref *ubufs)
{
kref_put(&ubufs->kref, vhost_zerocopy_done_signal);
}
void vhost_ubuf_put_and_wait(struct vhost_ubuf_ref *ubufs)
{
kref_put(&ubufs->kref, vhost_zerocopy_done_signal);
wait_event(ubufs->wait, !atomic_read(&ubufs->kref.refcount));
kfree(ubufs);
}

View file

@ -54,18 +54,6 @@ struct vhost_log {
struct vhost_virtqueue;
struct vhost_ubuf_ref {
struct kref kref;
wait_queue_head_t wait;
struct vhost_virtqueue *vq;
};
struct vhost_ubuf_ref *vhost_ubuf_alloc(struct vhost_virtqueue *, bool zcopy);
void vhost_ubuf_put(struct vhost_ubuf_ref *);
void vhost_ubuf_put_and_wait(struct vhost_ubuf_ref *);
struct ubuf_info;
/* The virtqueue structure describes a queue attached to a device. */
struct vhost_virtqueue {
struct vhost_dev *dev;
@ -130,16 +118,6 @@ struct vhost_virtqueue {
/* Log write descriptors */
void __user *log_base;
struct vhost_log *log;
/* vhost zerocopy support fields below: */
/* last used idx for outstanding DMA zerocopy buffers */
int upend_idx;
/* first used idx for DMA done zerocopy buffers */
int done_idx;
/* an array of userspace buffers info */
struct ubuf_info *ubuf_info;
/* Reference counting for outstanding ubufs.
* Protected by vq mutex. Writers must also take device mutex. */
struct vhost_ubuf_ref *ubufs;
};
struct vhost_dev {