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authorLinus Torvalds <torvalds@linux-foundation.org>2012-12-20 17:37:04 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-20 17:37:05 +0100
commitb7dfde956daee23f4439d0c8562a5e38b43e79d9 (patch)
tree2ed71fb5c5eac6957fd1e1ad0a67be6c3282167a /drivers
parentMerge tag 'sound-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/... (diff)
parentvirtio_console: Add support for remoteproc serial (diff)
downloadlinux-b7dfde956daee23f4439d0c8562a5e38b43e79d9.tar.xz
linux-b7dfde956daee23f4439d0c8562a5e38b43e79d9.zip
Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull virtio update from Rusty Russell: "Some nice cleanups, and even a patch my wife did as a "live" demo for Latinoware 2012. There's a slightly non-trivial merge in virtio-net, as we cleaned up the virtio add_buf interface while DaveM accepted the mq virtio-net patches." * tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (27 commits) virtio_console: Add support for remoteproc serial virtio_console: Merge struct buffer_token into struct port_buffer virtio: add drv_to_virtio to make code clearly virtio: use dev_to_virtio wrapper in virtio virtio-mmio: Fix irq parsing in command line parameter virtio_console: Free buffers from out-queue upon close virtio: Convert dev_printk(KERN_<LEVEL> to dev_<level>( virtio_console: Use kmalloc instead of kzalloc virtio_console: Free buffer if splice fails virtio: tools: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: scsi: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: rpmsg: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: net: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: console: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: make virtqueue_add_buf() returning 0 on success, not capacity. virtio: console: don't rely on virtqueue_add_buf() returning capacity. virtio_net: don't rely on virtqueue_add_buf() returning capacity. virtio-net: remove unused skb_vnet_hdr->num_sg field virtio-net: correct capacity math on ring full virtio: move queue_index and num_free fields into core struct virtqueue. ...
Diffstat (limited to 'drivers')
-rw-r--r--drivers/char/virtio_console.c329
-rw-r--r--drivers/lguest/core.c2
-rw-r--r--drivers/net/virtio_net.c48
-rw-r--r--drivers/rpmsg/virtio_rpmsg_bus.c6
-rw-r--r--drivers/scsi/virtio_scsi.c24
-rw-r--r--drivers/virtio/virtio.c30
-rw-r--r--drivers/virtio/virtio_balloon.c7
-rw-r--r--drivers/virtio/virtio_mmio.c30
-rw-r--r--drivers/virtio/virtio_pci.c20
-rw-r--r--drivers/virtio/virtio_ring.c46
10 files changed, 322 insertions, 220 deletions
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 90493d4ead1f..c594cb16c37b 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -37,8 +37,12 @@
#include <linux/wait.h>
#include <linux/workqueue.h>
#include <linux/module.h>
+#include <linux/dma-mapping.h>
+#include <linux/kconfig.h>
#include "../tty/hvc/hvc_console.h"
+#define is_rproc_enabled IS_ENABLED(CONFIG_REMOTEPROC)
+
/*
* This is a global struct for storing common data for all the devices
* this driver handles.
@@ -111,6 +115,21 @@ struct port_buffer {
size_t len;
/* offset in the buf from which to consume data */
size_t offset;
+
+ /* DMA address of buffer */
+ dma_addr_t dma;
+
+ /* Device we got DMA memory from */
+ struct device *dev;
+
+ /* List of pending dma buffers to free */
+ struct list_head list;
+
+ /* If sgpages == 0 then buf is used */
+ unsigned int sgpages;
+
+ /* sg is used if spages > 0. sg must be the last in is struct */
+ struct scatterlist sg[0];
};
/*
@@ -325,6 +344,11 @@ static bool is_console_port(struct port *port)
return false;
}
+static bool is_rproc_serial(const struct virtio_device *vdev)
+{
+ return is_rproc_enabled && vdev->id.device == VIRTIO_ID_RPROC_SERIAL;
+}
+
static inline bool use_multiport(struct ports_device *portdev)
{
/*
@@ -336,20 +360,110 @@ static inline bool use_multiport(struct ports_device *portdev)
return portdev->vdev->features[0] & (1 << VIRTIO_CONSOLE_F_MULTIPORT);
}
-static void free_buf(struct port_buffer *buf)
+static DEFINE_SPINLOCK(dma_bufs_lock);
+static LIST_HEAD(pending_free_dma_bufs);
+
+static void free_buf(struct port_buffer *buf, bool can_sleep)
{
- kfree(buf->buf);
+ unsigned int i;
+
+ for (i = 0; i < buf->sgpages; i++) {
+ struct page *page = sg_page(&buf->sg[i]);
+ if (!page)
+ break;
+ put_page(page);
+ }
+
+ if (!buf->dev) {
+ kfree(buf->buf);
+ } else if (is_rproc_enabled) {
+ unsigned long flags;
+
+ /* dma_free_coherent requires interrupts to be enabled. */
+ if (!can_sleep) {
+ /* queue up dma-buffers to be freed later */
+ spin_lock_irqsave(&dma_bufs_lock, flags);
+ list_add_tail(&buf->list, &pending_free_dma_bufs);
+ spin_unlock_irqrestore(&dma_bufs_lock, flags);
+ return;
+ }
+ dma_free_coherent(buf->dev, buf->size, buf->buf, buf->dma);
+
+ /* Release device refcnt and allow it to be freed */
+ put_device(buf->dev);
+ }
+
kfree(buf);
}
-static struct port_buffer *alloc_buf(size_t buf_size)
+static void reclaim_dma_bufs(void)
+{
+ unsigned long flags;
+ struct port_buffer *buf, *tmp;
+ LIST_HEAD(tmp_list);
+
+ if (list_empty(&pending_free_dma_bufs))
+ return;
+
+ /* Create a copy of the pending_free_dma_bufs while holding the lock */
+ spin_lock_irqsave(&dma_bufs_lock, flags);
+ list_cut_position(&tmp_list, &pending_free_dma_bufs,
+ pending_free_dma_bufs.prev);
+ spin_unlock_irqrestore(&dma_bufs_lock, flags);
+
+ /* Release the dma buffers, without irqs enabled */
+ list_for_each_entry_safe(buf, tmp, &tmp_list, list) {
+ list_del(&buf->list);
+ free_buf(buf, true);
+ }
+}
+
+static struct port_buffer *alloc_buf(struct virtqueue *vq, size_t buf_size,
+ int pages)
{
struct port_buffer *buf;
- buf = kmalloc(sizeof(*buf), GFP_KERNEL);
+ reclaim_dma_bufs();
+
+ /*
+ * Allocate buffer and the sg list. The sg list array is allocated
+ * directly after the port_buffer struct.
+ */
+ buf = kmalloc(sizeof(*buf) + sizeof(struct scatterlist) * pages,
+ GFP_KERNEL);
if (!buf)
goto fail;
- buf->buf = kzalloc(buf_size, GFP_KERNEL);
+
+ buf->sgpages = pages;
+ if (pages > 0) {
+ buf->dev = NULL;
+ buf->buf = NULL;
+ return buf;
+ }
+
+ if (is_rproc_serial(vq->vdev)) {
+ /*
+ * Allocate DMA memory from ancestor. When a virtio
+ * device is created by remoteproc, the DMA memory is
+ * associated with the grandparent device:
+ * vdev => rproc => platform-dev.
+ * The code here would have been less quirky if
+ * DMA_MEMORY_INCLUDES_CHILDREN had been supported
+ * in dma-coherent.c
+ */
+ if (!vq->vdev->dev.parent || !vq->vdev->dev.parent->parent)
+ goto free_buf;
+ buf->dev = vq->vdev->dev.parent->parent;
+
+ /* Increase device refcnt to avoid freeing it */
+ get_device(buf->dev);
+ buf->buf = dma_alloc_coherent(buf->dev, buf_size, &buf->dma,
+ GFP_KERNEL);
+ } else {
+ buf->dev = NULL;
+ buf->buf = kmalloc(buf_size, GFP_KERNEL);
+ }
+
if (!buf->buf)
goto free_buf;
buf->len = 0;
@@ -396,6 +510,8 @@ static int add_inbuf(struct virtqueue *vq, struct port_buffer *buf)
ret = virtqueue_add_buf(vq, sg, 0, 1, buf, GFP_ATOMIC);
virtqueue_kick(vq);
+ if (!ret)
+ ret = vq->num_free;
return ret;
}
@@ -416,7 +532,7 @@ static void discard_port_data(struct port *port)
port->stats.bytes_discarded += buf->len - buf->offset;
if (add_inbuf(port->in_vq, buf) < 0) {
err++;
- free_buf(buf);
+ free_buf(buf, false);
}
port->inbuf = NULL;
buf = get_inbuf(port);
@@ -459,7 +575,7 @@ static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id,
vq = portdev->c_ovq;
sg_init_one(sg, &cpkt, sizeof(cpkt));
- if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt, GFP_ATOMIC) >= 0) {
+ if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt, GFP_ATOMIC) == 0) {
virtqueue_kick(vq);
while (!virtqueue_get_buf(vq, &len))
cpu_relax();
@@ -476,55 +592,29 @@ static ssize_t send_control_msg(struct port *port, unsigned int event,
return 0;
}
-struct buffer_token {
- union {
- void *buf;
- struct scatterlist *sg;
- } u;
- /* If sgpages == 0 then buf is used, else sg is used */
- unsigned int sgpages;
-};
-
-static void reclaim_sg_pages(struct scatterlist *sg, unsigned int nrpages)
-{
- int i;
- struct page *page;
-
- for (i = 0; i < nrpages; i++) {
- page = sg_page(&sg[i]);
- if (!page)
- break;
- put_page(page);
- }
- kfree(sg);
-}
/* Callers must take the port->outvq_lock */
static void reclaim_consumed_buffers(struct port *port)
{
- struct buffer_token *tok;
+ struct port_buffer *buf;
unsigned int len;
if (!port->portdev) {
/* Device has been unplugged. vqs are already gone. */
return;
}
- while ((tok = virtqueue_get_buf(port->out_vq, &len))) {
- if (tok->sgpages)
- reclaim_sg_pages(tok->u.sg, tok->sgpages);
- else
- kfree(tok->u.buf);
- kfree(tok);
+ while ((buf = virtqueue_get_buf(port->out_vq, &len))) {
+ free_buf(buf, false);
port->outvq_full = false;
}
}
static ssize_t __send_to_port(struct port *port, struct scatterlist *sg,
int nents, size_t in_count,
- struct buffer_token *tok, bool nonblock)
+ void *data, bool nonblock)
{
struct virtqueue *out_vq;
- ssize_t ret;
+ int err;
unsigned long flags;
unsigned int len;
@@ -534,17 +624,17 @@ static ssize_t __send_to_port(struct port *port, struct scatterlist *sg,
reclaim_consumed_buffers(port);
- ret = virtqueue_add_buf(out_vq, sg, nents, 0, tok, GFP_ATOMIC);
+ err = virtqueue_add_buf(out_vq, sg, nents, 0, data, GFP_ATOMIC);
/* Tell Host to go! */
virtqueue_kick(out_vq);
- if (ret < 0) {
+ if (err) {
in_count = 0;
goto done;
}
- if (ret == 0)
+ if (out_vq->num_free == 0)
port->outvq_full = true;
if (nonblock)
@@ -572,37 +662,6 @@ done:
return in_count;
}
-static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count,
- bool nonblock)
-{
- struct scatterlist sg[1];
- struct buffer_token *tok;
-
- tok = kmalloc(sizeof(*tok), GFP_ATOMIC);
- if (!tok)
- return -ENOMEM;
- tok->sgpages = 0;
- tok->u.buf = in_buf;
-
- sg_init_one(sg, in_buf, in_count);
-
- return __send_to_port(port, sg, 1, in_count, tok, nonblock);
-}
-
-static ssize_t send_pages(struct port *port, struct scatterlist *sg, int nents,
- size_t in_count, bool nonblock)
-{
- struct buffer_token *tok;
-
- tok = kmalloc(sizeof(*tok), GFP_ATOMIC);
- if (!tok)
- return -ENOMEM;
- tok->sgpages = nents;
- tok->u.sg = sg;
-
- return __send_to_port(port, sg, nents, in_count, tok, nonblock);
-}
-
/*
* Give out the data that's requested from the buffer that we have
* queued up.
@@ -748,9 +807,10 @@ static ssize_t port_fops_write(struct file *filp, const char __user *ubuf,
size_t count, loff_t *offp)
{
struct port *port;
- char *buf;
+ struct port_buffer *buf;
ssize_t ret;
bool nonblock;
+ struct scatterlist sg[1];
/* Userspace could be out to fool us */
if (!count)
@@ -766,11 +826,11 @@ static ssize_t port_fops_write(struct file *filp, const char __user *ubuf,
count = min((size_t)(32 * 1024), count);
- buf = kmalloc(count, GFP_KERNEL);
+ buf = alloc_buf(port->out_vq, count, 0);
if (!buf)
return -ENOMEM;
- ret = copy_from_user(buf, ubuf, count);
+ ret = copy_from_user(buf->buf, ubuf, count);
if (ret) {
ret = -EFAULT;
goto free_buf;
@@ -784,13 +844,14 @@ static ssize_t port_fops_write(struct file *filp, const char __user *ubuf,
* through to the host.
*/
nonblock = true;
- ret = send_buf(port, buf, count, nonblock);
+ sg_init_one(sg, buf->buf, count);
+ ret = __send_to_port(port, sg, 1, count, buf, nonblock);
if (nonblock && ret > 0)
goto out;
free_buf:
- kfree(buf);
+ free_buf(buf, true);
out:
return ret;
}
@@ -856,6 +917,7 @@ static ssize_t port_fops_splice_write(struct pipe_inode_info *pipe,
struct port *port = filp->private_data;
struct sg_list sgl;
ssize_t ret;
+ struct port_buffer *buf;
struct splice_desc sd = {
.total_len = len,
.flags = flags,
@@ -863,22 +925,34 @@ static ssize_t port_fops_splice_write(struct pipe_inode_info *pipe,
.u.data = &sgl,
};
+ /*
+ * Rproc_serial does not yet support splice. To support splice
+ * pipe_to_sg() must allocate dma-buffers and copy content from
+ * regular pages to dma pages. And alloc_buf and free_buf must
+ * support allocating and freeing such a list of dma-buffers.
+ */
+ if (is_rproc_serial(port->out_vq->vdev))
+ return -EINVAL;
+
ret = wait_port_writable(port, filp->f_flags & O_NONBLOCK);
if (ret < 0)
return ret;
+ buf = alloc_buf(port->out_vq, 0, pipe->nrbufs);
+ if (!buf)
+ return -ENOMEM;
+
sgl.n = 0;
sgl.len = 0;
sgl.size = pipe->nrbufs;
- sgl.sg = kmalloc(sizeof(struct scatterlist) * sgl.size, GFP_KERNEL);
- if (unlikely(!sgl.sg))
- return -ENOMEM;
-
+ sgl.sg = buf->sg;
sg_init_table(sgl.sg, sgl.size);
ret = __splice_from_pipe(pipe, &sd, pipe_to_sg);
if (likely(ret > 0))
- ret = send_pages(port, sgl.sg, sgl.n, sgl.len, true);
+ ret = __send_to_port(port, buf->sg, sgl.n, sgl.len, buf, true);
+ if (unlikely(ret <= 0))
+ free_buf(buf, true);
return ret;
}
@@ -927,6 +1001,7 @@ static int port_fops_release(struct inode *inode, struct file *filp)
reclaim_consumed_buffers(port);
spin_unlock_irq(&port->outvq_lock);
+ reclaim_dma_bufs();
/*
* Locks aren't necessary here as a port can't be opened after
* unplug, and if a port isn't unplugged, a kref would already
@@ -1031,6 +1106,7 @@ static const struct file_operations port_fops = {
static int put_chars(u32 vtermno, const char *buf, int count)
{
struct port *port;
+ struct scatterlist sg[1];
if (unlikely(early_put_chars))
return early_put_chars(vtermno, buf, count);
@@ -1039,7 +1115,8 @@ static int put_chars(u32 vtermno, const char *buf, int count)
if (!port)
return -EPIPE;
- return send_buf(port, (void *)buf, count, false);
+ sg_init_one(sg, buf, count);
+ return __send_to_port(port, sg, 1, count, (void *)buf, false);
}
/*
@@ -1076,7 +1153,10 @@ static void resize_console(struct port *port)
return;
vdev = port->portdev->vdev;
- if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE))
+
+ /* Don't test F_SIZE at all if we're rproc: not a valid feature! */
+ if (!is_rproc_serial(vdev) &&
+ virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE))
hvc_resize(port->cons.hvc, port->cons.ws);
}
@@ -1260,7 +1340,7 @@ static unsigned int fill_queue(struct virtqueue *vq, spinlock_t *lock)
nr_added_bufs = 0;
do {
- buf = alloc_buf(PAGE_SIZE);
+ buf = alloc_buf(vq, PAGE_SIZE, 0);
if (!buf)
break;
@@ -1268,7 +1348,7 @@ static unsigned int fill_queue(struct virtqueue *vq, spinlock_t *lock)
ret = add_inbuf(vq, buf);
if (ret < 0) {
spin_unlock_irq(lock);
- free_buf(buf);
+ free_buf(buf, true);
break;
}
nr_added_bufs++;
@@ -1356,10 +1436,18 @@ static int add_port(struct ports_device *portdev, u32 id)
goto free_device;
}
- /*
- * If we're not using multiport support, this has to be a console port
- */
- if (!use_multiport(port->portdev)) {
+ if (is_rproc_serial(port->portdev->vdev))
+ /*
+ * For rproc_serial assume remote processor is connected.
+ * rproc_serial does not want the console port, only
+ * the generic port implementation.
+ */
+ port->host_connected = true;
+ else if (!use_multiport(port->portdev)) {
+ /*
+ * If we're not using multiport support,
+ * this has to be a console port.
+ */
err = init_port_console(port);
if (err)
goto free_inbufs;
@@ -1392,7 +1480,7 @@ static int add_port(struct ports_device *portdev, u32 id)
free_inbufs:
while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
- free_buf(buf);
+ free_buf(buf, true);
free_device:
device_destroy(pdrvdata.class, port->dev->devt);
free_cdev:
@@ -1434,7 +1522,11 @@ static void remove_port_data(struct port *port)
/* Remove buffers we queued up for the Host to send us data in. */
while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
- free_buf(buf);
+ free_buf(buf, true);
+
+ /* Free pending buffers from the out-queue. */
+ while ((buf = virtqueue_detach_unused_buf(port->out_vq)))
+ free_buf(buf, true);
}
/*
@@ -1636,7 +1728,7 @@ static void control_work_handler(struct work_struct *work)
if (add_inbuf(portdev->c_ivq, buf) < 0) {
dev_warn(&portdev->vdev->dev,
"Error adding buffer to queue\n");
- free_buf(buf);
+ free_buf(buf, false);
}
}
spin_unlock(&portdev->cvq_lock);
@@ -1832,10 +1924,10 @@ static void remove_controlq_data(struct ports_device *portdev)
return;
while ((buf = virtqueue_get_buf(portdev->c_ivq, &len)))
- free_buf(buf);
+ free_buf(buf, true);
while ((buf = virtqueue_detach_unused_buf(portdev->c_ivq)))
- free_buf(buf);
+ free_buf(buf, true);
}
/*
@@ -1882,11 +1974,15 @@ static int virtcons_probe(struct virtio_device *vdev)
multiport = false;
portdev->config.max_nr_ports = 1;
- if (virtio_config_val(vdev, VIRTIO_CONSOLE_F_MULTIPORT,
- offsetof(struct virtio_console_config,
- max_nr_ports),
- &portdev->config.max_nr_ports) == 0)
+
+ /* Don't test MULTIPORT at all if we're rproc: not a valid feature! */
+ if (!is_rproc_serial(vdev) &&
+ virtio_config_val(vdev, VIRTIO_CONSOLE_F_MULTIPORT,
+ offsetof(struct virtio_console_config,
+ max_nr_ports),
+ &portdev->config.max_nr_ports) == 0) {
multiport = true;
+ }
err = init_vqs(portdev);
if (err < 0) {
@@ -1996,6 +2092,16 @@ static unsigned int features[] = {
VIRTIO_CONSOLE_F_MULTIPORT,
};
+static struct virtio_device_id rproc_serial_id_table[] = {
+#if IS_ENABLED(CONFIG_REMOTEPROC)
+ { VIRTIO_ID_RPROC_SERIAL, VIRTIO_DEV_ANY_ID },
+#endif
+ { 0 },
+};
+
+static unsigned int rproc_serial_features[] = {
+};
+
#ifdef CONFIG_PM
static int virtcons_freeze(struct virtio_device *vdev)
{
@@ -2080,6 +2186,20 @@ static struct virtio_driver virtio_console = {
#endif
};
+/*
+ * virtio_rproc_serial refers to __devinit function which causes
+ * section mismatch warnings. So use __refdata to silence warnings.
+ */
+static struct virtio_driver __refdata virtio_rproc_serial = {
+ .feature_table = rproc_serial_features,
+ .feature_table_size = ARRAY_SIZE(rproc_serial_features),
+ .driver.name = "virtio_rproc_serial",
+ .driver.owner = THIS_MODULE,
+ .id_table = rproc_serial_id_table,
+ .probe = virtcons_probe,
+ .remove = virtcons_remove,
+};
+
static int __init init(void)
{
int err;
@@ -2104,7 +2224,15 @@ static int __init init(void)
pr_err("Error %d registering virtio driver\n", err);
goto free;
}
+ err = register_virtio_driver(&virtio_rproc_serial);
+ if (err < 0) {
+ pr_err("Error %d registering virtio rproc serial driver\n",
+ err);
+ goto unregister;
+ }
return 0;
+unregister:
+ unregister_virtio_driver(&virtio_console);
free:
if (pdrvdata.debugfs_dir)
debugfs_remove_recursive(pdrvdata.debugfs_dir);
@@ -2114,7 +2242,10 @@ free:
static void __exit fini(void)
{
+ reclaim_dma_bufs();
+
unregister_virtio_driver(&virtio_console);
+ unregister_virtio_driver(&virtio_rproc_serial);
class_destroy(pdrvdata.class);
if (pdrvdata.debugfs_dir)
diff --git a/drivers/lguest/core.c b/drivers/lguest/core.c
index b5fdcb78a75b..a5ebc0083d87 100644
--- a/drivers/lguest/core.c
+++ b/drivers/lguest/core.c
@@ -225,7 +225,7 @@ int run_guest(struct lg_cpu *cpu, unsigned long __user *user)
* eventfd (ie. the appropriate virtqueue thread)?
*/
if (!send_notify_to_eventfd(cpu)) {
- /* OK, we tell the main Laucher. */
+ /* OK, we tell the main Launcher. */
if (put_user(cpu->pending_notify, user))
return -EFAULT;
return sizeof(cpu->pending_notify);
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 68d64f0313ea..a6fcf15adc4f 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -130,7 +130,6 @@ struct skb_vnet_hdr {
struct virtio_net_hdr hdr;
struct virtio_net_hdr_mrg_rxbuf mhdr;
};
- unsigned int num_sg;
};
struct padded_vnet_hdr {
@@ -530,10 +529,10 @@ static bool try_fill_recv(struct receive_queue *rq, gfp_t gfp)
err = add_recvbuf_small(rq, gfp);
oom = err == -ENOMEM;
- if (err < 0)
+ if (err)
break;
++rq->num;
- } while (err > 0);
+ } while (rq->vq->num_free);
if (unlikely(rq->num > rq->max))
rq->max = rq->num;
virtqueue_kick(rq->vq);
@@ -640,10 +639,10 @@ static int virtnet_open(struct net_device *dev)
return 0;
}
-static unsigned int free_old_xmit_skbs(struct send_queue *sq)
+static void free_old_xmit_skbs(struct send_queue *sq)
{
struct sk_buff *skb;
- unsigned int len, tot_sgs = 0;
+ unsigned int len;
struct virtnet_info *vi = sq->vq->vdev->priv;
struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
@@ -655,10 +654,8 @@ static unsigned int free_old_xmit_skbs(struct send_queue *sq)
stats->tx_packets++;
u64_stats_update_end(&stats->tx_syncp);
- tot_sgs += skb_vnet_hdr(skb)->num_sg;
dev_kfree_skb_any(skb);
}
- return tot_sgs;
}
static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
@@ -666,6 +663,7 @@ static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb);
const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
struct virtnet_info *vi = sq->vq->vdev->priv;
+ unsigned num_sg;
pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
@@ -704,8 +702,8 @@ static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
else
sg_set_buf(sq->sg, &hdr->hdr, sizeof hdr->hdr);
- hdr->num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len) + 1;
- return virtqueue_add_buf(sq->vq, sq->sg, hdr->num_sg,
+ num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len) + 1;
+ return virtqueue_add_buf(sq->vq, sq->sg, num_sg,
0, skb, GFP_ATOMIC);
}
@@ -714,28 +712,20 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
struct virtnet_info *vi = netdev_priv(dev);
int qnum = skb_get_queue_mapping(skb);
struct send_queue *sq = &vi->sq[qnum];
- int capacity;
+ int err;
/* Free up any pending old buffers before queueing new ones. */
free_old_xmit_skbs(sq);
/* Try to transmit */
- capacity = xmit_skb(sq, skb);
-
- /* This can happen with OOM and indirect buffers. */
- if (unlikely(capacity < 0)) {
- if (likely(capacity == -ENOMEM)) {
- if (net_ratelimit())
- dev_warn(&dev->dev,
- "TXQ (%d) failure: out of memory\n",
- qnum);
- } else {
- dev->stats.tx_fifo_errors++;
- if (net_ratelimit())
- dev_warn(&dev->dev,
- "Unexpected TXQ (%d) failure: %d\n",
- qnum, capacity);
- }
+ err = xmit_skb(sq, skb);
+
+ /* This should not happen! */
+ if (unlikely(err)) {
+ dev->stats.tx_fifo_errors++;
+ if (net_ratelimit())
+ dev_warn(&dev->dev,
+ "Unexpected TXQ (%d) queue failure: %d\n", qnum, err);
dev->stats.tx_dropped++;
kfree_skb(skb);
return NETDEV_TX_OK;
@@ -748,12 +738,12 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
/* Apparently nice girls don't return TX_BUSY; stop the queue
* before it gets out of hand. Naturally, this wastes entries. */
- if (capacity < 2+MAX_SKB_FRAGS) {
+ if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
netif_stop_subqueue(dev, qnum);
if (unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
/* More just got used, free them then recheck. */
- capacity += free_old_xmit_skbs(sq);
- if (capacity >= 2+MAX_SKB_FRAGS) {
+ free_old_xmit_skbs(sq);
+ if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
netif_start_subqueue(dev, qnum);
virtqueue_disable_cb(sq->vq);
}
diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index 1859f71372e2..027096fe6a12 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -764,7 +764,7 @@ int rpmsg_send_offchannel_raw(struct rpmsg_channel *rpdev, u32 src, u32 dst,
/* add message to the remote processor's virtqueue */
err = virtqueue_add_buf(vrp->svq, &sg, 1, 0, msg, GFP_KERNEL);
- if (err < 0) {
+ if (err) {
/*
* need to reclaim the buffer here, otherwise it's lost
* (memory won't leak, but rpmsg won't use it again for TX).
@@ -776,8 +776,6 @@ int rpmsg_send_offchannel_raw(struct rpmsg_channel *rpdev, u32 src, u32 dst,
/* tell the remote processor it has a pending message to read */
virtqueue_kick(vrp->svq);
-
- err = 0;
out:
mutex_unlock(&vrp->tx_lock);
return err;
@@ -980,7 +978,7 @@ static int rpmsg_probe(struct virtio_device *vdev)
err = virtqueue_add_buf(vrp->rvq, &sg, 0, 1, cpu_addr,
GFP_KERNEL);
- WARN_ON(err < 0); /* sanity check; this can't really happen */
+ WARN_ON(err); /* sanity check; this can't really happen */
}
/* suppress "tx-complete" interrupts */
diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index dd8dc27fa32c..74ab67a169ec 100644
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c
@@ -215,7 +215,7 @@ static void virtscsi_ctrl_done(struct virtqueue *vq)
static int virtscsi_kick_event(struct virtio_scsi *vscsi,
struct virtio_scsi_event_node *event_node)
{
- int ret;
+ int err;
struct scatterlist sg;
unsigned long flags;
@@ -223,13 +223,14 @@ static int virtscsi_kick_event(struct virtio_scsi *vscsi,
spin_lock_irqsave(&vscsi->event_vq.vq_lock, flags);
- ret = virtqueue_add_buf(vscsi->event_vq.vq, &sg, 0, 1, event_node, GFP_ATOMIC);
- if (ret >= 0)
+ err = virtqueue_add_buf(vscsi->event_vq.vq, &sg, 0, 1, event_node,
+ GFP_ATOMIC);
+ if (!err)
virtqueue_kick(vscsi->event_vq.vq);
spin_unlock_irqrestore(&vscsi->event_vq.vq_lock, flags);
- return ret;
+ return err;
}
static int virtscsi_kick_event_all(struct virtio_scsi *vscsi)
@@ -410,22 +411,23 @@ static int virtscsi_kick_cmd(struct virtio_scsi_target_state *tgt,
{
unsigned int out_num, in_num;
unsigned long flags;
- int ret;
+ int err;
+ bool needs_kick = false;
spin_lock_irqsave(&tgt->tgt_lock, flags);
virtscsi_map_cmd(tgt, cmd, &out_num, &in_num, req_size, resp_size);
spin_lock(&vq->vq_lock);
- ret = virtqueue_add_buf(vq->vq, tgt->sg, out_num, in_num, cmd, gfp);
+ err = virtqueue_add_buf(vq->vq, tgt->sg, out_num, in_num, cmd, gfp);
spin_unlock(&tgt->tgt_lock);
- if (ret >= 0)
- ret = virtqueue_kick_prepare(vq->vq);
+ if (!err)
+ needs_kick = virtqueue_kick_prepare(vq->vq);
spin_unlock_irqrestore(&vq->vq_lock, flags);
- if (ret > 0)
+ if (needs_kick)
virtqueue_notify(vq->vq);
- return ret;
+ return err;
}
static int virtscsi_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
@@ -467,7 +469,7 @@ static int virtscsi_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
if (virtscsi_kick_cmd(tgt, &vscsi->req_vq, cmd,
sizeof cmd->req.cmd, sizeof cmd->resp.cmd,
- GFP_ATOMIC) >= 0)
+ GFP_ATOMIC) == 0)
ret = 0;
else
mempool_free(cmd, virtscsi_cmd_pool);
diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index 809b0de59c09..ee59b74768d9 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -10,33 +10,32 @@ static DEFINE_IDA(virtio_index_ida);
static ssize_t device_show(struct device *_d,
struct device_attribute *attr, char *buf)
{
- struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
+ struct virtio_device *dev = dev_to_virtio(_d);
return sprintf(buf, "0x%04x\n", dev->id.device);
}
static ssize_t vendor_show(struct device *_d,
struct device_attribute *attr, char *buf)
{
- struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
+ struct virtio_device *dev = dev_to_virtio(_d);
return sprintf(buf, "0x%04x\n", dev->id.vendor);
}
static ssize_t status_show(struct device *_d,
struct device_attribute *attr, char *buf)
{
- struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
+ struct virtio_device *dev = dev_to_virtio(_d);
return sprintf(buf, "0x%08x\n", dev->config->get_status(dev));
}
static ssize_t modalias_show(struct device *_d,
struct device_attribute *attr, char *buf)
{
- struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
-
+ struct virtio_device *dev = dev_to_virtio(_d);
return sprintf(buf, "virtio:d%08Xv%08X\n",
dev->id.device, dev->id.vendor);
}
static ssize_t features_show(struct device *_d,
struct device_attribute *attr, char *buf)
{
- struct virtio_device *dev = container_of(_d, struct virtio_device, dev);
+ struct virtio_device *dev = dev_to_virtio(_d);
unsigned int i;
ssize_t len = 0;
@@ -71,10 +70,10 @@ static inline int virtio_id_match(const struct virtio_device *dev,
static int virtio_dev_match(struct device *_dv, struct device_driver *_dr)
{
unsigned int i;
- struct virtio_device *dev = container_of(_dv,struct virtio_device,dev);
+ struct virtio_device *dev = dev_to_virtio(_dv);
const struct virtio_device_id *ids;
- ids = container_of(_dr, struct virtio_driver, driver)->id_table;
+ ids = drv_to_virtio(_dr)->id_table;
for (i = 0; ids[i].device; i++)
if (virtio_id_match(dev, &ids[i]))
return 1;
@@ -83,7 +82,7 @@ static int virtio_dev_match(struct device *_dv, struct device_driver *_dr)
static int virtio_uevent(struct device *_dv, struct kobj_uevent_env *env)
{
- struct virtio_device *dev = container_of(_dv,struct virtio_device,dev);
+ struct virtio_device *dev = dev_to_virtio(_dv);
return add_uevent_var(env, "MODALIAS=virtio:d%08Xv%08X",
dev->id.device, dev->id.vendor);
@@ -98,8 +97,7 @@ void virtio_check_driver_offered_feature(const struct virtio_device *vdev,
unsigned int fbit)
{
unsigned int i;
- struct virtio_driver *drv = container_of(vdev->dev.driver,
- struct virtio_driver, driver);
+ struct virtio_driver *drv = drv_to_virtio(vdev->dev.driver);
for (i = 0; i < drv->feature_table_size; i++)
if (drv->feature_table[i] == fbit)
@@ -111,9 +109,8 @@ EXPORT_SYMBOL_GPL(virtio_check_driver_offered_feature);
static int virtio_dev_probe(struct device *_d)
{
int err, i;
- struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
- struct virtio_driver *drv = container_of(dev->dev.driver,
- struct virtio_driver, driver);
+ struct virtio_device *dev = dev_to_virtio(_d);
+ struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
u32 device_features;
/* We have a driver! */
@@ -152,9 +149,8 @@ static int virtio_dev_probe(struct device *_d)
static int virtio_dev_remove(struct device *_d)
{
- struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
- struct virtio_driver *drv = container_of(dev->dev.driver,
- struct virtio_driver, driver);
+ struct virtio_device *dev = dev_to_virtio(_d);
+ struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
drv->remove(dev);
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 2a70558b36ea..d19fe3e323b4 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -139,10 +139,9 @@ static void fill_balloon(struct virtio_balloon *vb, size_t num)
struct page *page = balloon_page_enqueue(vb_dev_info);
if (!page) {
- if (printk_ratelimit())
- dev_printk(KERN_INFO, &vb->vdev->dev,
- "Out of puff! Can't get %u pages\n",
- VIRTIO_BALLOON_PAGES_PER_PAGE);
+ dev_info_ratelimited(&vb->vdev->dev,
+ "Out of puff! Can't get %u pages\n",
+ VIRTIO_BALLOON_PAGES_PER_PAGE);
/* Sleep for at least 1/5 of a second before retry. */
msleep(200);
break;
diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
index 6b1b7e184939..634f80bcdbd7 100644
--- a/drivers/virtio/virtio_mmio.c
+++ b/drivers/virtio/virtio_mmio.c
@@ -225,7 +225,7 @@ static void vm_notify(struct virtqueue *vq)
/* We write the queue's selector into the notification register to
* signal the other end */
- writel(virtqueue_get_queue_index(vq), vm_dev->base + VIRTIO_MMIO_QUEUE_NOTIFY);
+ writel(vq->index, vm_dev->base + VIRTIO_MMIO_QUEUE_NOTIFY);
}
/* Notify all virtqueues on an interrupt. */
@@ -266,7 +266,7 @@ static void vm_del_vq(struct virtqueue *vq)
struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev);
struct virtio_mmio_vq_info *info = vq->priv;
unsigned long flags, size;
- unsigned int index = virtqueue_get_queue_index(vq);
+ unsigned int index = vq->index;
spin_lock_irqsave(&vm_dev->lock, flags);
list_del(&info->node);
@@ -521,25 +521,33 @@ static int vm_cmdline_set(const char *device,
int err;
struct resource resources[2] = {};
char *str;
- long long int base;
+ long long int base, size;
+ unsigned int irq;
int processed, consumed = 0;
struct platform_device *pdev;
- resources[0].flags = IORESOURCE_MEM;
- resources[1].flags = IORESOURCE_IRQ;
-
- resources[0].end = memparse(device, &str) - 1;
+ /* Consume "size" part of the command line parameter */
+ size = memparse(device, &str);
+ /* Get "@<base>:<irq>[:<id>]" chunks */
processed = sscanf(str, "@%lli:%u%n:%d%n",
- &base, &resources[1].start, &consumed,
+ &base, &irq, &consumed,
&vm_cmdline_id, &consumed);
- if (processed < 2 || processed > 3 || str[consumed])
+ /*
+ * sscanf() must processes at least 2 chunks; also there
+ * must be no extra characters after the last chunk, so
+ * str[consumed] must be '\0'
+ */
+ if (processed < 2 || str[consumed])
return -EINVAL;
+ resources[0].flags = IORESOURCE_MEM;
resources[0].start = base;
- resources[0].end += base;
- resources[1].end = resources[1].start;
+ resources[0].end = base + size - 1;
+
+ resources[1].flags = IORESOURCE_IRQ;
+ resources[1].start = resources[1].end = irq;
if (!vm_cmdline_parent_registered) {
err = device_register(&vm_cmdline_parent);
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index c33aea36598a..e3ecc94591ad 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -203,8 +203,7 @@ static void vp_notify(struct virtqueue *vq)
/* we write the queue's selector into the notification register to
* signal the other end */
- iowrite16(virtqueue_get_queue_index(vq),
- vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
+ iowrite16(vq->index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
}
/* Handle a configuration change: Tell driver if it wants to know. */
@@ -479,8 +478,7 @@ static void vp_del_vq(struct virtqueue *vq)
list_del(&info->node);
spin_unlock_irqrestore(&vp_dev->lock, flags);
- iowrite16(virtqueue_get_queue_index(vq),
- vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
+ iowrite16(vq->index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
if (vp_dev->msix_enabled) {
iowrite16(VIRTIO_MSI_NO_VECTOR,
@@ -830,16 +828,4 @@ static struct pci_driver virtio_pci_driver = {
#endif
};
-static int __init virtio_pci_init(void)
-{
- return pci_register_driver(&virtio_pci_driver);
-}
-
-module_init(virtio_pci_init);
-
-static void __exit virtio_pci_exit(void)
-{
- pci_unregister_driver(&virtio_pci_driver);
-}
-
-module_exit(virtio_pci_exit);
+module_pci_driver(virtio_pci_driver);
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index e639584b2dbd..ffd7e7da5d3b 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -93,8 +93,6 @@ struct vring_virtqueue
/* Host publishes avail event idx */
bool event;
- /* Number of free buffers */
- unsigned int num_free;
/* Head of free buffer list. */
unsigned int free_head;
/* Number we've added since last sync. */
@@ -106,9 +104,6 @@ struct vring_virtqueue
/* How to notify other side. FIXME: commonalize hcalls! */
void (*notify)(struct virtqueue *vq);
- /* Index of the queue */
- int queue_index;
-
#ifdef DEBUG
/* They're supposed to lock for us. */
unsigned int in_use;
@@ -135,6 +130,13 @@ static int vring_add_indirect(struct vring_virtqueue *vq,
unsigned head;
int i;
+ /*
+ * We require lowmem mappings for the descriptors because
+ * otherwise virt_to_phys will give us bogus addresses in the
+ * virtqueue.
+ */
+ gfp &= ~(__GFP_HIGHMEM | __GFP_HIGH);
+
desc = kmalloc((out + in) * sizeof(struct vring_desc), gfp);
if (!desc)
return -ENOMEM;
@@ -160,7 +162,7 @@ static int vring_add_indirect(struct vring_virtqueue *vq,
desc[i-1].next = 0;
/* We're about to use a buffer */
- vq->num_free--;
+ vq->vq.num_free--;
/* Use a single buffer which doesn't continue */
head = vq->free_head;
@@ -174,13 +176,6 @@ static int vring_add_indirect(struct vring_virtqueue *vq,
return head;
}
-int virtqueue_get_queue_index(struct virtqueue *_vq)
-{
- struct vring_virtqueue *vq = to_vvq(_vq);
- return vq->queue_index;
-}
-EXPORT_SYMBOL_GPL(virtqueue_get_queue_index);
-
/**
* virtqueue_add_buf - expose buffer to other end
* @vq: the struct virtqueue we're talking about.
@@ -193,10 +188,7 @@ EXPORT_SYMBOL_GPL(virtqueue_get_queue_index);
* Caller must ensure we don't call this with other virtqueue operations
* at the same time (except where noted).
*
- * Returns remaining capacity of queue or a negative error
- * (ie. ENOSPC). Note that it only really makes sense to treat all
- * positive return values as "available": indirect buffers mean that
- * we can put an entire sg[] array inside a single queue entry.
+ * Returns zero or a negative error (ie. ENOSPC, ENOMEM).
*/
int virtqueue_add_buf(struct virtqueue *_vq,
struct scatterlist sg[],
@@ -228,7 +220,7 @@ int virtqueue_add_buf(struct virtqueue *_vq,
/* If the host supports indirect descriptor tables, and we have multiple
* buffers, then go indirect. FIXME: tune this threshold */
- if (vq->indirect && (out + in) > 1 && vq->num_free) {
+ if (vq->indirect && (out + in) > 1 && vq->vq.num_free) {
head = vring_add_indirect(vq, sg, out, in, gfp);
if (likely(head >= 0))
goto add_head;
@@ -237,9 +229,9 @@ int virtqueue_add_buf(struct virtqueue *_vq,
BUG_ON(out + in > vq->vring.num);
BUG_ON(out + in == 0);
- if (vq->num_free < out + in) {
+ if (vq->vq.num_free < out + in) {
pr_debug("Can't add buf len %i - avail = %i\n",
- out + in, vq->num_free);
+ out + in, vq->vq.num_free);
/* FIXME: for historical reasons, we force a notify here if
* there are outgoing parts to the buffer. Presumably the
* host should service the ring ASAP. */
@@ -250,7 +242,7 @@ int virtqueue_add_buf(struct virtqueue *_vq,
}
/* We're about to use some buffers from the free list. */
- vq->num_free -= out + in;
+ vq->vq.num_free -= out + in;
head = vq->free_head;
for (i = vq->free_head; out; i = vq->vring.desc[i].next, out--) {
@@ -296,7 +288,7 @@ add_head:
pr_debug("Added buffer head %i to %p\n", head, vq);
END_USE(vq);
- return vq->num_free;
+ return 0;
}
EXPORT_SYMBOL_GPL(virtqueue_add_buf);
@@ -393,13 +385,13 @@ static void detach_buf(struct vring_virtqueue *vq, unsigned int head)
while (vq->vring.desc[i].flags & VRING_DESC_F_NEXT) {
i = vq->vring.desc[i].next;
- vq->num_free++;
+ vq->vq.num_free++;
}
vq->vring.desc[i].next = vq->free_head;
vq->free_head = head;
/* Plus final descriptor */
- vq->num_free++;
+ vq->vq.num_free++;
}
static inline bool more_used(const struct vring_virtqueue *vq)
@@ -599,7 +591,7 @@ void *virtqueue_detach_unused_buf(struct virtqueue *_vq)
return buf;
}
/* That should have freed everything. */
- BUG_ON(vq->num_free != vq->vring.num);
+ BUG_ON(vq->vq.num_free != vq->vring.num);
END_USE(vq);
return NULL;
@@ -653,12 +645,13 @@ struct virtqueue *vring_new_virtqueue(unsigned int index,
vq->vq.callback = callback;
vq->vq.vdev = vdev;
vq->vq.name = name;
+ vq->vq.num_free = num;
+ vq->vq.index = index;
vq->notify = notify;
vq->weak_barriers = weak_barriers;
vq->broken = false;
vq->last_used_idx = 0;
vq->num_added = 0;
- vq->queue_index = index;
list_add_tail(&vq->vq.list, &vdev->vqs);
#ifdef DEBUG
vq->in_use = false;
@@ -673,7 +666,6 @@ struct virtqueue *vring_new_virtqueue(unsigned int index,
vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;
/* Put everything in free lists. */
- vq->num_free = num;
vq->free_head = 0;
for (i = 0; i < num-1; i++) {
vq->vring.desc[i].next = i+1;