[PATCH net-next 6/8] vhost: move -net specific code out

Michael S. Tsirkin
2012-10-29T15:47:58Z

Zerocopy handling code is vhost-net specific.
Move it from vhost.c/vhost.h out to net.c

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
drivers/vhost/net.c | 45 ++++++++++++++++++++++++++++++++++++++++
drivers/vhost/tcm_vhost.c | 1 +
drivers/vhost/vhost.c | 53 +++++++----------------------------------------
drivers/vhost/vhost.h | 21 +++----------------
4 files changed, 56 insertions(+), 64 deletions(-)

diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index f80ae5f..532fc88 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -126,6 +126,42 @@ static void tx_poll_start(struct vhost_net *net, struct socket *sock)
net->tx_poll_state = VHOST_NET_POLL_STARTED;
}

+/* In case of DMA done not in order in lower device driver for some reason.
+ * upend_idx is used to track end of used idx, done_idx is used to track head
+ * of used idx. Once lower device DMA done contiguously, we will signal KVM
+ * guest used idx.
+ */
+int vhost_zerocopy_signal_used(struct vhost_virtqueue *vq)
+{
+ int i;
+ int j = 0;
+
+ for (i = vq->done_idx; i != vq->upend_idx; i = (i + 1) % UIO_MAXIOV) {
+ if (VHOST_DMA_IS_DONE(vq->heads[i].len)) {
+ vq->heads[i].len = VHOST_DMA_CLEAR_LEN;
+ vhost_add_used_and_signal(vq->dev, vq,
+ vq->heads[i].id, 0);
+ ++j;
+ } else
+ break;
+ }
+ if (j)
+ vq->done_idx = i;
+ return j;
+}
+
+static void vhost_zerocopy_callback(struct ubuf_info *ubuf, int status)
+{
+ struct vhost_ubuf_ref *ubufs = ubuf->ctx;
+ struct vhost_virtqueue *vq = ubufs->vq;
+
+ vhost_poll_queue(&vq->poll);
+ /* set len to mark this desc buffers done DMA */
+ vq->heads[ubuf->desc].len = status ?
+ VHOST_DMA_FAILED_LEN : VHOST_DMA_DONE_LEN;
+ vhost_ubuf_put(ubufs);
+}
+
/* Expects to be always run from workqueue - which acts as
* read-size critical section for our kind of RCU. */
static void handle_tx(struct vhost_net *net)
@@ -594,9 +630,18 @@ static int vhost_net_release(struct inode *inode, struct file *f)
struct vhost_net *n = f->private_data;
struct socket *tx_sock;
struct socket *rx_sock;
+ int i;

vhost_net_stop(n, &tx_sock, &rx_sock);
vhost_net_flush(n);
+ vhost_dev_stop(&n->dev);
+ for (i = 0; i < n->dev.nvqs; ++i) {
+ /* Wait for all lower device DMAs done. */
+ if (n->dev.vqs[i].ubufs)
+ vhost_ubuf_put_and_wait(n->dev.vqs[i].ubufs);
+
+ vhost_zerocopy_signal_used(n, &n->dev.vqs[i]);
+ }
vhost_dev_cleanup(&n->dev, false);
if (tx_sock)
fput(tx_sock->file);
diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c
index aa31692..23c138f 100644
--- a/drivers/vhost/tcm_vhost.c
+++ b/drivers/vhost/tcm_vhost.c
@@ -895,6 +895,7 @@ static int vhost_scsi_release(struct inode *inode, struct file *f)
vhost_scsi_clear_endpoint(s, &backend);
}

+ vhost_dev_stop(&s->dev);
vhost_dev_cleanup(&s->dev, false);
kfree(s);
return 0;
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 5affce3..ef8f598 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -26,10 +26,6 @@
#include <linux/kthread.h>
#include <linux/cgroup.h>

-#include <linux/net.h>
-#include <linux/if_packet.h>
-#include <linux/if_arp.h>
-
#include "vhost.h"

enum {
@@ -414,28 +410,16 @@ long vhost_dev_reset_owner(struct vhost_dev *dev)
return 0;
}

-/* In case of DMA done not in order in lower device driver for some reason.
- * upend_idx is used to track end of used idx, done_idx is used to track head
- * of used idx. Once lower device DMA done contiguously, we will signal KVM
- * guest used idx.
- */
-int vhost_zerocopy_signal_used(struct vhost_virtqueue *vq)
+void vhost_dev_stop(struct vhost_dev *dev)
{
int i;
- int j = 0;
-
- for (i = vq->done_idx; i != vq->upend_idx; i = (i + 1) % UIO_MAXIOV) {
- if (VHOST_DMA_IS_DONE(vq->heads[i].len)) {
- vq->heads[i].len = VHOST_DMA_CLEAR_LEN;
- vhost_add_used_and_signal(vq->dev, vq,
- vq->heads[i].id, 0);
- ++j;
- } else
- break;
+
+ for (i = 0; i < dev->nvqs; ++i) {
+ if (dev->vqs[i].kick && dev->vqs[i].handle_kick) {
+ vhost_poll_stop(&dev->vqs[i].poll);
+ vhost_poll_flush(&dev->vqs[i].poll);
+ }
}
- if (j)
- vq->done_idx = i;
- return j;
}

/* Caller should have device mutex if and only if locked is set */
@@ -444,17 +428,6 @@ void vhost_dev_cleanup(struct vhost_dev *dev, bool locked)
int i;

for (i = 0; i < dev->nvqs; ++i) {
- if (dev->vqs[i].kick && dev->vqs[i].handle_kick) {
- vhost_poll_stop(&dev->vqs[i].poll);
- vhost_poll_flush(&dev->vqs[i].poll);
- }
- /* Wait for all lower device DMAs done. */
- if (dev->vqs[i].ubufs)
- vhost_ubuf_put_and_wait(dev->vqs[i].ubufs);
-
- /* Signal guest as appropriate. */
- vhost_zerocopy_signal_used(&dev->vqs[i]);
-
if (dev->vqs[i].error_ctx)
eventfd_ctx_put(dev->vqs[i].error_ctx);
if (dev->vqs[i].error)
@@ -1599,15 +1572,3 @@ void vhost_ubuf_put_and_wait(struct vhost_ubuf_ref *ubufs)
wait_event(ubufs->wait, !atomic_read(&ubufs->kref.refcount));
kfree(ubufs);
}
-
-void vhost_zerocopy_callback(struct ubuf_info *ubuf, int status)
-{
- struct vhost_ubuf_ref *ubufs = ubuf->ctx;
- struct vhost_virtqueue *vq = ubufs->vq;
-
- vhost_poll_queue(&vq->poll);
- /* set len to mark this desc buffers done DMA */
- vq->heads[ubuf->desc].len = status ?
- VHOST_DMA_FAILED_LEN : VHOST_DMA_DONE_LEN;
- kref_put(&ubufs->kref, vhost_zerocopy_done_signal);
-}
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index 6fdf31d..5e19e3d 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -7,27 +7,11 @@
#include <linux/mutex.h>
#include <linux/poll.h>
#include <linux/file.h>
-#include <linux/skbuff.h>
#include <linux/uio.h>
#include <linux/virtio_config.h>
#include <linux/virtio_ring.h>
#include <linux/atomic.h>

-/*
- * For transmit, used buffer len is unused; we override it to track buffer
- * status internally; used for zerocopy tx only.
- */
-/* Lower device DMA failed */
-#define VHOST_DMA_FAILED_LEN 3
-/* Lower device DMA done */
-#define VHOST_DMA_DONE_LEN 2
-/* Lower device DMA in progress */
-#define VHOST_DMA_IN_PROGRESS 1
-/* Buffer unused */
-#define VHOST_DMA_CLEAR_LEN 0
-
-#define VHOST_DMA_IS_DONE(len) ((len) >= VHOST_DMA_DONE_LEN)
-
struct vhost_device;

struct vhost_work;
@@ -80,6 +64,8 @@ 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;
@@ -177,6 +163,7 @@ long vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue *vqs, int nvqs);
long vhost_dev_check_owner(struct vhost_dev *);
long vhost_dev_reset_owner(struct vhost_dev *);
void vhost_dev_cleanup(struct vhost_dev *, bool locked);
+void vhost_dev_stop(struct vhost_dev *);
long vhost_dev_ioctl(struct vhost_dev *, unsigned int ioctl, unsigned long arg);
int vhost_vq_access_ok(struct vhost_virtqueue *vq);
int vhost_log_access_ok(struct vhost_dev *);
@@ -201,8 +188,6 @@ bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *);

int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
unsigned int log_num, u64 len);
-void vhost_zerocopy_callback(struct ubuf_info *, int);
-int vhost_zerocopy_signal_used(struct vhost_virtqueue *vq);

#define vq_err(vq, fmt, ...) do { \
pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \
--
MST