Asias He
2013-Apr-27 07:07 UTC
[PATCH] vhost: Move vhost-net zerocopy support 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 at redhat.com>
---
drivers/vhost/net.c | 164 +++++++++++++++++++++++++++++++++++++++++++-------
drivers/vhost/vhost.c | 57 +-----------------
drivers/vhost/vhost.h | 22 -------
3 files changed, 142 insertions(+), 101 deletions(-)
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 683d9a1..c194045 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -70,8 +70,24 @@ enum vhost_net_poll_state {
VHOST_NET_POLL_STOPPED = 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 {
@@ -92,6 +108,88 @@ 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;
@@ -189,10 +287,12 @@ static int tx_poll_start(struct vhost_net *net, struct
socket *sock)
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)) {
@@ -204,7 +304,7 @@ static int vhost_zerocopy_signal_used(struct vhost_net *net,
break;
}
if (j)
- vq->done_idx = i;
+ nvq->done_idx = i;
return j;
}
@@ -235,6 +335,7 @@ 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 = {
@@ -271,7 +372,7 @@ static void handle_tx(struct vhost_net *net)
if (wmem < sock->sk->sk_sndbuf / 2)
tx_poll_stop(net);
hdr_size = vq->vhost_hlen;
- zcopy = vq->ubufs;
+ zcopy = nvq->ubufs;
for (;;) {
/* Release DMAs done buffers first */
@@ -298,9 +399,10 @@ 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)) {
tx_poll_start(net, sock);
set_bit(SOCK_ASYNC_NOSPACE, &sock->flags);
@@ -329,34 +431,34 @@ 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);
@@ -364,8 +466,8 @@ 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);
if (err == -EAGAIN || err == -ENOBUFS)
@@ -617,7 +719,7 @@ 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;
@@ -632,6 +734,12 @@ 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);
@@ -710,15 +818,15 @@ 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);
}
}
@@ -733,6 +841,7 @@ 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)
@@ -814,6 +923,7 @@ 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;
@@ -827,6 +937,7 @@ 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. */
@@ -859,8 +970,8 @@ 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;
@@ -911,6 +1022,7 @@ 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)
@@ -986,11 +1098,17 @@ 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;
}
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 3f80286..40e0540 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -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])
@@ -188,9 +186,6 @@ 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)
@@ -250,20 +245,12 @@ 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 *
@@ -272,14 +259,8 @@ 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;
@@ -318,7 +299,6 @@ 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]);
@@ -1548,38 +1528,3 @@ 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);
-}
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index f3afa8a..3a36712 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -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 {
--
1.8.1.4
Possibly Parallel Threads
Wisdom of the Ancients
