* [PATCH] vhost: break out of polling loop on error
@ 2010-06-27 8:59 Michael S. Tsirkin
2010-06-28 17:11 ` Sridhar Samudrala
0 siblings, 1 reply; 3+ messages in thread
From: Michael S. Tsirkin @ 2010-06-27 8:59 UTC (permalink / raw)
To: Sridhar Samudrala, Arnd Bergmann, Paul E. McKenney, Juan Quintela,
Rusty Russell
When ring parsing fails, we currently handle this
as ring empty condition. This means that we enable
kicks and recheck ring empty: if this not empty,
we re-start polling which of course will fail again.
Instead, let's return a negative error code and stop polling.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
Dave, I'm sending this out so it can get reviewed.
I'll put this on my vhost tree
so no need for you to pick this patch directly.
drivers/vhost/net.c | 12 ++++++++++--
drivers/vhost/vhost.c | 33 +++++++++++++++++----------------
drivers/vhost/vhost.h | 8 ++++----
3 files changed, 31 insertions(+), 22 deletions(-)
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 0f41c91..54096ee 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -98,7 +98,8 @@ static void tx_poll_start(struct vhost_net *net, struct socket *sock)
static void handle_tx(struct vhost_net *net)
{
struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_TX];
- unsigned head, out, in, s;
+ unsigned out, in, s;
+ int head;
struct msghdr msg = {
.msg_name = NULL,
.msg_namelen = 0,
@@ -135,6 +136,9 @@ static void handle_tx(struct vhost_net *net)
ARRAY_SIZE(vq->iov),
&out, &in,
NULL, NULL);
+ /* On error, stop handling until the next kick. */
+ if (head < 0)
+ break;
/* Nothing new? Wait for eventfd to tell us they refilled. */
if (head == vq->num) {
wmem = atomic_read(&sock->sk->sk_wmem_alloc);
@@ -192,7 +196,8 @@ static void handle_tx(struct vhost_net *net)
static void handle_rx(struct vhost_net *net)
{
struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX];
- unsigned head, out, in, log, s;
+ unsigned out, in, log, s;
+ int head;
struct vhost_log *vq_log;
struct msghdr msg = {
.msg_name = NULL,
@@ -228,6 +233,9 @@ static void handle_rx(struct vhost_net *net)
ARRAY_SIZE(vq->iov),
&out, &in,
vq_log, &log);
+ /* On error, stop handling until the next kick. */
+ if (head < 0)
+ break;
/* OK, now we need to know about added descriptors. */
if (head == vq->num) {
if (unlikely(vhost_enable_notify(vq))) {
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 3b83382..5ccd384 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -873,12 +873,13 @@ static unsigned get_indirect(struct vhost_dev *dev, struct vhost_virtqueue *vq,
* number of output then some number of input descriptors, it's actually two
* iovecs, but we pack them into one and note how many of each there were.
*
- * This function returns the descriptor number found, or vq->num (which
- * is never a valid descriptor number) if none was found. */
-unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
- struct iovec iov[], unsigned int iov_size,
- unsigned int *out_num, unsigned int *in_num,
- struct vhost_log *log, unsigned int *log_num)
+ * This function returns the descriptor number found, or vq->num (which is
+ * never a valid descriptor number) if none was found. A negative code is
+ * returned on error. */
+int vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
+ struct iovec iov[], unsigned int iov_size,
+ unsigned int *out_num, unsigned int *in_num,
+ struct vhost_log *log, unsigned int *log_num)
{
struct vring_desc desc;
unsigned int i, head, found = 0;
@@ -890,13 +891,13 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
if (get_user(vq->avail_idx, &vq->avail->idx)) {
vq_err(vq, "Failed to access avail idx at %p\n",
&vq->avail->idx);
- return vq->num;
+ return -EFAULT;
}
if ((u16)(vq->avail_idx - last_avail_idx) > vq->num) {
vq_err(vq, "Guest moved used index from %u to %u",
last_avail_idx, vq->avail_idx);
- return vq->num;
+ return -EFAULT;
}
/* If there's nothing new since last we looked, return invalid. */
@@ -912,14 +913,14 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
vq_err(vq, "Failed to read head: idx %d address %p\n",
last_avail_idx,
&vq->avail->ring[last_avail_idx % vq->num]);
- return vq->num;
+ return -EFAULT;
}
/* If their number is silly, that's an error. */
if (head >= vq->num) {
vq_err(vq, "Guest says index %u > %u is available",
head, vq->num);
- return vq->num;
+ return -EINVAL;
}
/* When we start there are none of either input nor output. */
@@ -933,19 +934,19 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
if (i >= vq->num) {
vq_err(vq, "Desc index is %u > %u, head = %u",
i, vq->num, head);
- return vq->num;
+ return -EINVAL;
}
if (++found > vq->num) {
vq_err(vq, "Loop detected: last one at %u "
"vq size %u head %u\n",
i, vq->num, head);
- return vq->num;
+ return -EINVAL;
}
ret = copy_from_user(&desc, vq->desc + i, sizeof desc);
if (ret) {
vq_err(vq, "Failed to get descriptor: idx %d addr %p\n",
i, vq->desc + i);
- return vq->num;
+ return -EFAULT;
}
if (desc.flags & VRING_DESC_F_INDIRECT) {
ret = get_indirect(dev, vq, iov, iov_size,
@@ -954,7 +955,7 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
if (ret < 0) {
vq_err(vq, "Failure detected "
"in indirect descriptor at idx %d\n", i);
- return vq->num;
+ return ret;
}
continue;
}
@@ -964,7 +965,7 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
if (ret < 0) {
vq_err(vq, "Translation failure %d descriptor idx %d\n",
ret, i);
- return vq->num;
+ return ret;
}
if (desc.flags & VRING_DESC_F_WRITE) {
/* If this is an input descriptor,
@@ -981,7 +982,7 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
if (*in_num) {
vq_err(vq, "Descriptor has out after in: "
"idx %d\n", i);
- return vq->num;
+ return -EINVAL;
}
*out_num += ret;
}
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index 44591ba..11ee13d 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -120,10 +120,10 @@ 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 *);
-unsigned vhost_get_vq_desc(struct vhost_dev *, struct vhost_virtqueue *,
- struct iovec iov[], unsigned int iov_count,
- unsigned int *out_num, unsigned int *in_num,
- struct vhost_log *log, unsigned int *log_num);
+int vhost_get_vq_desc(struct vhost_dev *, struct vhost_virtqueue *,
+ struct iovec iov[], unsigned int iov_count,
+ unsigned int *out_num, unsigned int *in_num,
+ struct vhost_log *log, unsigned int *log_num);
void vhost_discard_vq_desc(struct vhost_virtqueue *);
int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len);
--
1.7.1.12.g42b7f
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] vhost: break out of polling loop on error
2010-06-27 8:59 [PATCH] vhost: break out of polling loop on error Michael S. Tsirkin
@ 2010-06-28 17:11 ` Sridhar Samudrala
2010-06-28 17:25 ` Michael S. Tsirkin
0 siblings, 1 reply; 3+ messages in thread
From: Sridhar Samudrala @ 2010-06-28 17:11 UTC (permalink / raw)
To: Michael S. Tsirkin
Cc: Sridhar Samudrala, Arnd Bergmann, Paul E. McKenney, Juan Quintela,
Rusty Russell, Jes.Sorensen, kraxel, Takuya Yoshikawa, kvm,
virtualization, netdev, linux-kernel
On Sun, 2010-06-27 at 11:59 +0300, Michael S. Tsirkin wrote:
> When ring parsing fails, we currently handle this
> as ring empty condition. This means that we enable
> kicks and recheck ring empty: if this not empty,
> we re-start polling which of course will fail again.
>
> Instead, let's return a negative error code and stop polling.
One minor comment on error return below. With that change,
Acked-by: Sridhar Samudrala <sri@us.ibm.com>
>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> ---
>
> Dave, I'm sending this out so it can get reviewed.
> I'll put this on my vhost tree
> so no need for you to pick this patch directly.
>
> drivers/vhost/net.c | 12 ++++++++++--
> drivers/vhost/vhost.c | 33 +++++++++++++++++----------------
> drivers/vhost/vhost.h | 8 ++++----
> 3 files changed, 31 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
> index 0f41c91..54096ee 100644
> --- a/drivers/vhost/net.c
> +++ b/drivers/vhost/net.c
> @@ -98,7 +98,8 @@ static void tx_poll_start(struct vhost_net *net, struct socket *sock)
> static void handle_tx(struct vhost_net *net)
> {
> struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_TX];
> - unsigned head, out, in, s;
> + unsigned out, in, s;
> + int head;
> struct msghdr msg = {
> .msg_name = NULL,
> .msg_namelen = 0,
> @@ -135,6 +136,9 @@ static void handle_tx(struct vhost_net *net)
> ARRAY_SIZE(vq->iov),
> &out, &in,
> NULL, NULL);
> + /* On error, stop handling until the next kick. */
> + if (head < 0)
> + break;
> /* Nothing new? Wait for eventfd to tell us they refilled. */
> if (head == vq->num) {
> wmem = atomic_read(&sock->sk->sk_wmem_alloc);
> @@ -192,7 +196,8 @@ static void handle_tx(struct vhost_net *net)
> static void handle_rx(struct vhost_net *net)
> {
> struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX];
> - unsigned head, out, in, log, s;
> + unsigned out, in, log, s;
> + int head;
> struct vhost_log *vq_log;
> struct msghdr msg = {
> .msg_name = NULL,
> @@ -228,6 +233,9 @@ static void handle_rx(struct vhost_net *net)
> ARRAY_SIZE(vq->iov),
> &out, &in,
> vq_log, &log);
> + /* On error, stop handling until the next kick. */
> + if (head < 0)
> + break;
> /* OK, now we need to know about added descriptors. */
> if (head == vq->num) {
> if (unlikely(vhost_enable_notify(vq))) {
> diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
> index 3b83382..5ccd384 100644
> --- a/drivers/vhost/vhost.c
> +++ b/drivers/vhost/vhost.c
> @@ -873,12 +873,13 @@ static unsigned get_indirect(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> * number of output then some number of input descriptors, it's actually two
> * iovecs, but we pack them into one and note how many of each there were.
> *
> - * This function returns the descriptor number found, or vq->num (which
> - * is never a valid descriptor number) if none was found. */
> -unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> - struct iovec iov[], unsigned int iov_size,
> - unsigned int *out_num, unsigned int *in_num,
> - struct vhost_log *log, unsigned int *log_num)
> + * This function returns the descriptor number found, or vq->num (which is
> + * never a valid descriptor number) if none was found. A negative code is
> + * returned on error. */
> +int vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> + struct iovec iov[], unsigned int iov_size,
> + unsigned int *out_num, unsigned int *in_num,
> + struct vhost_log *log, unsigned int *log_num)
> {
> struct vring_desc desc;
> unsigned int i, head, found = 0;
> @@ -890,13 +891,13 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> if (get_user(vq->avail_idx, &vq->avail->idx)) {
> vq_err(vq, "Failed to access avail idx at %p\n",
> &vq->avail->idx);
> - return vq->num;
> + return -EFAULT;
> }
>
> if ((u16)(vq->avail_idx - last_avail_idx) > vq->num) {
> vq_err(vq, "Guest moved used index from %u to %u",
> last_avail_idx, vq->avail_idx);
> - return vq->num;
> + return -EFAULT;
This should be -EINVAL
> }
>
> /* If there's nothing new since last we looked, return invalid. */
> @@ -912,14 +913,14 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> vq_err(vq, "Failed to read head: idx %d address %p\n",
> last_avail_idx,
> &vq->avail->ring[last_avail_idx % vq->num]);
> - return vq->num;
> + return -EFAULT;
> }
>
> /* If their number is silly, that's an error. */
> if (head >= vq->num) {
> vq_err(vq, "Guest says index %u > %u is available",
> head, vq->num);
> - return vq->num;
> + return -EINVAL;
> }
>
> /* When we start there are none of either input nor output. */
> @@ -933,19 +934,19 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> if (i >= vq->num) {
> vq_err(vq, "Desc index is %u > %u, head = %u",
> i, vq->num, head);
> - return vq->num;
> + return -EINVAL;
> }
> if (++found > vq->num) {
> vq_err(vq, "Loop detected: last one at %u "
> "vq size %u head %u\n",
> i, vq->num, head);
> - return vq->num;
> + return -EINVAL;
> }
> ret = copy_from_user(&desc, vq->desc + i, sizeof desc);
> if (ret) {
> vq_err(vq, "Failed to get descriptor: idx %d addr %p\n",
> i, vq->desc + i);
> - return vq->num;
> + return -EFAULT;
> }
> if (desc.flags & VRING_DESC_F_INDIRECT) {
> ret = get_indirect(dev, vq, iov, iov_size,
> @@ -954,7 +955,7 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> if (ret < 0) {
> vq_err(vq, "Failure detected "
> "in indirect descriptor at idx %d\n", i);
> - return vq->num;
> + return ret;
> }
> continue;
> }
> @@ -964,7 +965,7 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> if (ret < 0) {
> vq_err(vq, "Translation failure %d descriptor idx %d\n",
> ret, i);
> - return vq->num;
> + return ret;
> }
> if (desc.flags & VRING_DESC_F_WRITE) {
> /* If this is an input descriptor,
> @@ -981,7 +982,7 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> if (*in_num) {
> vq_err(vq, "Descriptor has out after in: "
> "idx %d\n", i);
> - return vq->num;
> + return -EINVAL;
> }
> *out_num += ret;
> }
> diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
> index 44591ba..11ee13d 100644
> --- a/drivers/vhost/vhost.h
> +++ b/drivers/vhost/vhost.h
> @@ -120,10 +120,10 @@ 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 *);
>
> -unsigned vhost_get_vq_desc(struct vhost_dev *, struct vhost_virtqueue *,
> - struct iovec iov[], unsigned int iov_count,
> - unsigned int *out_num, unsigned int *in_num,
> - struct vhost_log *log, unsigned int *log_num);
> +int vhost_get_vq_desc(struct vhost_dev *, struct vhost_virtqueue *,
> + struct iovec iov[], unsigned int iov_count,
> + unsigned int *out_num, unsigned int *in_num,
> + struct vhost_log *log, unsigned int *log_num);
> void vhost_discard_vq_desc(struct vhost_virtqueue *);
>
> int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len);
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] vhost: break out of polling loop on error
2010-06-28 17:11 ` Sridhar Samudrala
@ 2010-06-28 17:25 ` Michael S. Tsirkin
0 siblings, 0 replies; 3+ messages in thread
From: Michael S. Tsirkin @ 2010-06-28 17:25 UTC (permalink / raw)
To: Sridhar Samudrala
Cc: Sridhar Samudrala, Arnd Bergmann, Paul E. McKenney, Juan Quintela,
Rusty Russell, Jes.Sorensen, kraxel, Takuya Yoshikawa, kvm,
virtualization, netdev, linux-kernel
On Mon, Jun 28, 2010 at 10:11:43AM -0700, Sridhar Samudrala wrote:
> On Sun, 2010-06-27 at 11:59 +0300, Michael S. Tsirkin wrote:
> > When ring parsing fails, we currently handle this
> > as ring empty condition. This means that we enable
> > kicks and recheck ring empty: if this not empty,
> > we re-start polling which of course will fail again.
> >
> > Instead, let's return a negative error code and stop polling.
>
> One minor comment on error return below. With that change,
>
> Acked-by: Sridhar Samudrala <sri@us.ibm.com>
Right. In fact, we don't really use the return code,
and the generated binary is smaller if we return
-EINVAL always.
So that's what I'll do.
> >
> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> > ---
> >
> > Dave, I'm sending this out so it can get reviewed.
> > I'll put this on my vhost tree
> > so no need for you to pick this patch directly.
> >
> > drivers/vhost/net.c | 12 ++++++++++--
> > drivers/vhost/vhost.c | 33 +++++++++++++++++----------------
> > drivers/vhost/vhost.h | 8 ++++----
> > 3 files changed, 31 insertions(+), 22 deletions(-)
> >
> > diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
> > index 0f41c91..54096ee 100644
> > --- a/drivers/vhost/net.c
> > +++ b/drivers/vhost/net.c
> > @@ -98,7 +98,8 @@ static void tx_poll_start(struct vhost_net *net, struct socket *sock)
> > static void handle_tx(struct vhost_net *net)
> > {
> > struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_TX];
> > - unsigned head, out, in, s;
> > + unsigned out, in, s;
> > + int head;
> > struct msghdr msg = {
> > .msg_name = NULL,
> > .msg_namelen = 0,
> > @@ -135,6 +136,9 @@ static void handle_tx(struct vhost_net *net)
> > ARRAY_SIZE(vq->iov),
> > &out, &in,
> > NULL, NULL);
> > + /* On error, stop handling until the next kick. */
> > + if (head < 0)
> > + break;
> > /* Nothing new? Wait for eventfd to tell us they refilled. */
> > if (head == vq->num) {
> > wmem = atomic_read(&sock->sk->sk_wmem_alloc);
> > @@ -192,7 +196,8 @@ static void handle_tx(struct vhost_net *net)
> > static void handle_rx(struct vhost_net *net)
> > {
> > struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX];
> > - unsigned head, out, in, log, s;
> > + unsigned out, in, log, s;
> > + int head;
> > struct vhost_log *vq_log;
> > struct msghdr msg = {
> > .msg_name = NULL,
> > @@ -228,6 +233,9 @@ static void handle_rx(struct vhost_net *net)
> > ARRAY_SIZE(vq->iov),
> > &out, &in,
> > vq_log, &log);
> > + /* On error, stop handling until the next kick. */
> > + if (head < 0)
> > + break;
> > /* OK, now we need to know about added descriptors. */
> > if (head == vq->num) {
> > if (unlikely(vhost_enable_notify(vq))) {
> > diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
> > index 3b83382..5ccd384 100644
> > --- a/drivers/vhost/vhost.c
> > +++ b/drivers/vhost/vhost.c
> > @@ -873,12 +873,13 @@ static unsigned get_indirect(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> > * number of output then some number of input descriptors, it's actually two
> > * iovecs, but we pack them into one and note how many of each there were.
> > *
> > - * This function returns the descriptor number found, or vq->num (which
> > - * is never a valid descriptor number) if none was found. */
> > -unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> > - struct iovec iov[], unsigned int iov_size,
> > - unsigned int *out_num, unsigned int *in_num,
> > - struct vhost_log *log, unsigned int *log_num)
> > + * This function returns the descriptor number found, or vq->num (which is
> > + * never a valid descriptor number) if none was found. A negative code is
> > + * returned on error. */
> > +int vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> > + struct iovec iov[], unsigned int iov_size,
> > + unsigned int *out_num, unsigned int *in_num,
> > + struct vhost_log *log, unsigned int *log_num)
> > {
> > struct vring_desc desc;
> > unsigned int i, head, found = 0;
> > @@ -890,13 +891,13 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> > if (get_user(vq->avail_idx, &vq->avail->idx)) {
> > vq_err(vq, "Failed to access avail idx at %p\n",
> > &vq->avail->idx);
> > - return vq->num;
> > + return -EFAULT;
> > }
> >
> > if ((u16)(vq->avail_idx - last_avail_idx) > vq->num) {
> > vq_err(vq, "Guest moved used index from %u to %u",
> > last_avail_idx, vq->avail_idx);
> > - return vq->num;
> > + return -EFAULT;
>
> This should be -EINVAL
> > }
> >
> > /* If there's nothing new since last we looked, return invalid. */
> > @@ -912,14 +913,14 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> > vq_err(vq, "Failed to read head: idx %d address %p\n",
> > last_avail_idx,
> > &vq->avail->ring[last_avail_idx % vq->num]);
> > - return vq->num;
> > + return -EFAULT;
> > }
> >
> > /* If their number is silly, that's an error. */
> > if (head >= vq->num) {
> > vq_err(vq, "Guest says index %u > %u is available",
> > head, vq->num);
> > - return vq->num;
> > + return -EINVAL;
> > }
> >
> > /* When we start there are none of either input nor output. */
> > @@ -933,19 +934,19 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> > if (i >= vq->num) {
> > vq_err(vq, "Desc index is %u > %u, head = %u",
> > i, vq->num, head);
> > - return vq->num;
> > + return -EINVAL;
> > }
> > if (++found > vq->num) {
> > vq_err(vq, "Loop detected: last one at %u "
> > "vq size %u head %u\n",
> > i, vq->num, head);
> > - return vq->num;
> > + return -EINVAL;
> > }
> > ret = copy_from_user(&desc, vq->desc + i, sizeof desc);
> > if (ret) {
> > vq_err(vq, "Failed to get descriptor: idx %d addr %p\n",
> > i, vq->desc + i);
> > - return vq->num;
> > + return -EFAULT;
> > }
> > if (desc.flags & VRING_DESC_F_INDIRECT) {
> > ret = get_indirect(dev, vq, iov, iov_size,
> > @@ -954,7 +955,7 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> > if (ret < 0) {
> > vq_err(vq, "Failure detected "
> > "in indirect descriptor at idx %d\n", i);
> > - return vq->num;
> > + return ret;
> > }
> > continue;
> > }
> > @@ -964,7 +965,7 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> > if (ret < 0) {
> > vq_err(vq, "Translation failure %d descriptor idx %d\n",
> > ret, i);
> > - return vq->num;
> > + return ret;
> > }
> > if (desc.flags & VRING_DESC_F_WRITE) {
> > /* If this is an input descriptor,
> > @@ -981,7 +982,7 @@ unsigned vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
> > if (*in_num) {
> > vq_err(vq, "Descriptor has out after in: "
> > "idx %d\n", i);
> > - return vq->num;
> > + return -EINVAL;
> > }
> > *out_num += ret;
> > }
> > diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
> > index 44591ba..11ee13d 100644
> > --- a/drivers/vhost/vhost.h
> > +++ b/drivers/vhost/vhost.h
> > @@ -120,10 +120,10 @@ 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 *);
> >
> > -unsigned vhost_get_vq_desc(struct vhost_dev *, struct vhost_virtqueue *,
> > - struct iovec iov[], unsigned int iov_count,
> > - unsigned int *out_num, unsigned int *in_num,
> > - struct vhost_log *log, unsigned int *log_num);
> > +int vhost_get_vq_desc(struct vhost_dev *, struct vhost_virtqueue *,
> > + struct iovec iov[], unsigned int iov_count,
> > + unsigned int *out_num, unsigned int *in_num,
> > + struct vhost_log *log, unsigned int *log_num);
> > void vhost_discard_vq_desc(struct vhost_virtqueue *);
> >
> > int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len);
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2010-06-28 17:31 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2010-06-27 8:59 [PATCH] vhost: break out of polling loop on error Michael S. Tsirkin
2010-06-28 17:11 ` Sridhar Samudrala
2010-06-28 17:25 ` Michael S. Tsirkin
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