Re: [PATCH vhost 01/22] virtio_ring: virtqueue_set_dma_premapped support disable
On Thu, 12 Oct 2023 05:40:38 -0400, "Michael S. Tsirkin"
wrote:
> On Thu, Oct 12, 2023 at 05:18:54PM +0800, Xuan Zhuo wrote:
> > On Thu, 12 Oct 2023 05:15:52 -0400, "Michael S. Tsirkin"
> > wrote:
> > > On Wed, Oct 11, 2023 at 05:27:07PM +0800, Xuan Zhuo wrote:
> > > > virtqueue_set_dma_premapped() adds a new parameter to disable the
> > > > virtqueue premapped mode.
> > > >
> > > > Signed-off-by: Xuan Zhuo
> > > > ---
> > > > drivers/net/virtio_net.c | 2 +-
> > > > drivers/virtio/virtio_ring.c | 11 ---
> > > > include/linux/virtio.h | 2 +-
> > > > 3 files changed, 10 insertions(+), 5 deletions(-)
> > > >
> > > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> > > > index fe7f314d65c9..6b5f47ebf9b2 100644
> > > > --- a/drivers/net/virtio_net.c
> > > > +++ b/drivers/net/virtio_net.c
> > > > @@ -737,7 +737,7 @@ static void virtnet_rq_set_premapped(struct
> > > > virtnet_info *vi)
> > > > return;
> > > >
> > > > for (i = 0; i < vi->max_queue_pairs; i++) {
> > > > - if (virtqueue_set_dma_premapped(vi->rq[i].vq))
> > > > + if (virtqueue_set_dma_premapped(vi->rq[i].vq, true))
> > > > continue;
> > > >
> > > > vi->rq[i].do_dma = true;
> > > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> > > > index 51d8f3299c10..b3ded56722f4 100644
> > > > --- a/drivers/virtio/virtio_ring.c
> > > > +++ b/drivers/virtio/virtio_ring.c
> > > > @@ -2784,7 +2784,7 @@ EXPORT_SYMBOL_GPL(virtqueue_resize);
> > > > * 0: success.
> > > > * -EINVAL: vring does not use the dma api, so we can not enable
> > > > premapped mode.
> > > > */
> > > > -int virtqueue_set_dma_premapped(struct virtqueue *_vq)
> > > > +int virtqueue_set_dma_premapped(struct virtqueue *_vq, bool mode)
> > > > {
> > > > struct vring_virtqueue *vq = to_vvq(_vq);
> > > > u32 num;
> > > > @@ -2803,8 +2803,13 @@ int virtqueue_set_dma_premapped(struct virtqueue
> > > > *_vq)
> > > > return -EINVAL;
> > > > }
> > > >
> > > > - vq->premapped = true;
> > > > - vq->do_unmap = false;
> > > > + if (mode) {
> > > > + vq->premapped = true;
> > > > + vq->do_unmap = false;
> > > > + } else {
> > > > + vq->premapped = false;
> > > > + vq->do_unmap = vq->use_dma_api;
> > > > + }
> > > >
> > > > END_USE(vq);
> > > >
> > > > diff --git a/include/linux/virtio.h b/include/linux/virtio.h
> > > > index 4cc614a38376..1cf7b004348b 100644
> > > > --- a/include/linux/virtio.h
> > > > +++ b/include/linux/virtio.h
> > > > @@ -81,7 +81,7 @@ bool virtqueue_enable_cb(struct virtqueue *vq);
> > > >
> > > > unsigned virtqueue_enable_cb_prepare(struct virtqueue *vq);
> > > >
> > > > -int virtqueue_set_dma_premapped(struct virtqueue *_vq);
> > > > +int virtqueue_set_dma_premapped(struct virtqueue *_vq, bool mode);
> > > >
> > > > bool virtqueue_poll(struct virtqueue *vq, unsigned);
> > >
> > > Wait a sec I thought we never change premapped. If you make this
> > > dynamic don't you need a bunch of locking?
> > > Or maybe queue is empty when you change this?
> > > If yes pls add a bunch of BUG_ON checks to make sure this is not misused.
> >
> >
> > Actually, this api is called immediately after the vq init or vq reset.
> >
> > We already have such a check.
> >
> > Thanks.
> >
> > /**
> > * virtqueue_set_dma_premapped - set the vring premapped mode
> > * @_vq: the struct virtqueue we're talking about.
> > *
> > * Enable the premapped mode of the vq.
> > *
> > * The vring in premapped mode does not do dma internally, so the driver
> > must
> > * do dma mapping in advance. The driver must pass the dma_address through
> > * dma_address of scatterlist. When the driver got a used buffer from
> > * the vring, it has to unmap the dma address.
> > *
> > * This function must be called immediately after creating the vq, or after
> > vq
> > * reset, and before adding any buffers to it.
> > *
> > * Caller must ensure we don't call this with other virtqueue operations
> > * at the same time (except where noted).
> > *
> > * Returns zero or a negative error.
> > * 0: success.
> > * -EINVAL: vring does not use the dma api, so we can not enable premapped
> > mode.
> > */
> > int virtqueue_set_dma_premapped(struct virtqueue *_vq, bool mode)
> > {
> > struct vring_virtqueue *vq = to_vvq(_vq);
> > u32 num;
> >
> > START_USE(vq);
> >
> > num = vq->packed_ring ? vq->packed.vring.num : vq->split.vring.num;
> >
> > --> if (num != vq->vq.num_free) {
> > END_USE(vq);
> > return -EINVAL;
> > }
>
> But it turns out virtnet_rq_set_premapped actually just ignores errors.
> So returning EINVAL here does nothing caller just proceeds?
> And checking num_free without locks is never safe anyway.
The premise of all this is that this is called immediately after reset
Re: [PATCH vhost 01/22] virtio_ring: virtqueue_set_dma_premapped support disable
On Thu, Oct 12, 2023 at 05:18:54PM +0800, Xuan Zhuo wrote:
> On Thu, 12 Oct 2023 05:15:52 -0400, "Michael S. Tsirkin"
> wrote:
> > On Wed, Oct 11, 2023 at 05:27:07PM +0800, Xuan Zhuo wrote:
> > > virtqueue_set_dma_premapped() adds a new parameter to disable the
> > > virtqueue premapped mode.
> > >
> > > Signed-off-by: Xuan Zhuo
> > > ---
> > > drivers/net/virtio_net.c | 2 +-
> > > drivers/virtio/virtio_ring.c | 11 ---
> > > include/linux/virtio.h | 2 +-
> > > 3 files changed, 10 insertions(+), 5 deletions(-)
> > >
> > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> > > index fe7f314d65c9..6b5f47ebf9b2 100644
> > > --- a/drivers/net/virtio_net.c
> > > +++ b/drivers/net/virtio_net.c
> > > @@ -737,7 +737,7 @@ static void virtnet_rq_set_premapped(struct
> > > virtnet_info *vi)
> > > return;
> > >
> > > for (i = 0; i < vi->max_queue_pairs; i++) {
> > > - if (virtqueue_set_dma_premapped(vi->rq[i].vq))
> > > + if (virtqueue_set_dma_premapped(vi->rq[i].vq, true))
> > > continue;
> > >
> > > vi->rq[i].do_dma = true;
> > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> > > index 51d8f3299c10..b3ded56722f4 100644
> > > --- a/drivers/virtio/virtio_ring.c
> > > +++ b/drivers/virtio/virtio_ring.c
> > > @@ -2784,7 +2784,7 @@ EXPORT_SYMBOL_GPL(virtqueue_resize);
> > > * 0: success.
> > > * -EINVAL: vring does not use the dma api, so we can not enable
> > > premapped mode.
> > > */
> > > -int virtqueue_set_dma_premapped(struct virtqueue *_vq)
> > > +int virtqueue_set_dma_premapped(struct virtqueue *_vq, bool mode)
> > > {
> > > struct vring_virtqueue *vq = to_vvq(_vq);
> > > u32 num;
> > > @@ -2803,8 +2803,13 @@ int virtqueue_set_dma_premapped(struct virtqueue
> > > *_vq)
> > > return -EINVAL;
> > > }
> > >
> > > - vq->premapped = true;
> > > - vq->do_unmap = false;
> > > + if (mode) {
> > > + vq->premapped = true;
> > > + vq->do_unmap = false;
> > > + } else {
> > > + vq->premapped = false;
> > > + vq->do_unmap = vq->use_dma_api;
> > > + }
> > >
> > > END_USE(vq);
> > >
> > > diff --git a/include/linux/virtio.h b/include/linux/virtio.h
> > > index 4cc614a38376..1cf7b004348b 100644
> > > --- a/include/linux/virtio.h
> > > +++ b/include/linux/virtio.h
> > > @@ -81,7 +81,7 @@ bool virtqueue_enable_cb(struct virtqueue *vq);
> > >
> > > unsigned virtqueue_enable_cb_prepare(struct virtqueue *vq);
> > >
> > > -int virtqueue_set_dma_premapped(struct virtqueue *_vq);
> > > +int virtqueue_set_dma_premapped(struct virtqueue *_vq, bool mode);
> > >
> > > bool virtqueue_poll(struct virtqueue *vq, unsigned);
> >
> > Wait a sec I thought we never change premapped. If you make this
> > dynamic don't you need a bunch of locking?
> > Or maybe queue is empty when you change this?
> > If yes pls add a bunch of BUG_ON checks to make sure this is not misused.
>
>
> Actually, this api is called immediately after the vq init or vq reset.
>
> We already have such a check.
>
> Thanks.
>
> /**
> * virtqueue_set_dma_premapped - set the vring premapped mode
> * @_vq: the struct virtqueue we're talking about.
> *
> * Enable the premapped mode of the vq.
> *
> * The vring in premapped mode does not do dma internally, so the driver must
> * do dma mapping in advance. The driver must pass the dma_address through
> * dma_address of scatterlist. When the driver got a used buffer from
> * the vring, it has to unmap the dma address.
> *
> * This function must be called immediately after creating the vq, or after vq
> * reset, and before adding any buffers to it.
> *
> * Caller must ensure we don't call this with other virtqueue operations
> * at the same time (except where noted).
> *
> * Returns zero or a negative error.
> * 0: success.
> * -EINVAL: vring does not use the dma api, so we can not enable premapped
> mode.
> */
> int virtqueue_set_dma_premapped(struct virtqueue *_vq, bool mode)
> {
> struct vring_virtqueue *vq = to_vvq(_vq);
> u32 num;
>
> START_USE(vq);
>
> num = vq->packed_ring ? vq->packed.vring.num : vq->split.vring.num;
>
> --> if (num != vq->vq.num_free) {
> END_USE(vq);
> return -EINVAL;
> }
But it turns out virtnet_rq_set_premapped actually just ignores errors.
So returning EINVAL here does nothing caller just proceeds?
And checking num_free without locks is never safe anyway.
I think the point is that this never triggers then just BUG_ON.
>
> if (!vq->use_dma_api) {
> END_USE(vq);
> return -EINVAL;
> }
>
> if (mode) {
> vq->premapped = true;
> vq->do_unmap = false;
> } else {
> vq->premapped = false;
> vq->do_unmap = vq->use_dma_api;
> }
>
> END_USE(vq);
>
> return 0;
> }
> EXPORT_SYMBOL_GPL(virtqueue_set_dma_premapped);
>
>
Re: [PATCH vhost 01/22] virtio_ring: virtqueue_set_dma_premapped support disable
On Thu, 12 Oct 2023 05:15:52 -0400, "Michael S. Tsirkin"
wrote:
> On Wed, Oct 11, 2023 at 05:27:07PM +0800, Xuan Zhuo wrote:
> > virtqueue_set_dma_premapped() adds a new parameter to disable the
> > virtqueue premapped mode.
> >
> > Signed-off-by: Xuan Zhuo
> > ---
> > drivers/net/virtio_net.c | 2 +-
> > drivers/virtio/virtio_ring.c | 11 ---
> > include/linux/virtio.h | 2 +-
> > 3 files changed, 10 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> > index fe7f314d65c9..6b5f47ebf9b2 100644
> > --- a/drivers/net/virtio_net.c
> > +++ b/drivers/net/virtio_net.c
> > @@ -737,7 +737,7 @@ static void virtnet_rq_set_premapped(struct
> > virtnet_info *vi)
> > return;
> >
> > for (i = 0; i < vi->max_queue_pairs; i++) {
> > - if (virtqueue_set_dma_premapped(vi->rq[i].vq))
> > + if (virtqueue_set_dma_premapped(vi->rq[i].vq, true))
> > continue;
> >
> > vi->rq[i].do_dma = true;
> > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> > index 51d8f3299c10..b3ded56722f4 100644
> > --- a/drivers/virtio/virtio_ring.c
> > +++ b/drivers/virtio/virtio_ring.c
> > @@ -2784,7 +2784,7 @@ EXPORT_SYMBOL_GPL(virtqueue_resize);
> > * 0: success.
> > * -EINVAL: vring does not use the dma api, so we can not enable premapped
> > mode.
> > */
> > -int virtqueue_set_dma_premapped(struct virtqueue *_vq)
> > +int virtqueue_set_dma_premapped(struct virtqueue *_vq, bool mode)
> > {
> > struct vring_virtqueue *vq = to_vvq(_vq);
> > u32 num;
> > @@ -2803,8 +2803,13 @@ int virtqueue_set_dma_premapped(struct virtqueue
> > *_vq)
> > return -EINVAL;
> > }
> >
> > - vq->premapped = true;
> > - vq->do_unmap = false;
> > + if (mode) {
> > + vq->premapped = true;
> > + vq->do_unmap = false;
> > + } else {
> > + vq->premapped = false;
> > + vq->do_unmap = vq->use_dma_api;
> > + }
> >
> > END_USE(vq);
> >
> > diff --git a/include/linux/virtio.h b/include/linux/virtio.h
> > index 4cc614a38376..1cf7b004348b 100644
> > --- a/include/linux/virtio.h
> > +++ b/include/linux/virtio.h
> > @@ -81,7 +81,7 @@ bool virtqueue_enable_cb(struct virtqueue *vq);
> >
> > unsigned virtqueue_enable_cb_prepare(struct virtqueue *vq);
> >
> > -int virtqueue_set_dma_premapped(struct virtqueue *_vq);
> > +int virtqueue_set_dma_premapped(struct virtqueue *_vq, bool mode);
> >
> > bool virtqueue_poll(struct virtqueue *vq, unsigned);
>
> Wait a sec I thought we never change premapped. If you make this
> dynamic don't you need a bunch of locking?
> Or maybe queue is empty when you change this?
> If yes pls add a bunch of BUG_ON checks to make sure this is not misused.
Actually, this api is called immediately after the vq init or vq reset.
We already have such a check.
Thanks.
/**
* virtqueue_set_dma_premapped - set the vring premapped mode
* @_vq: the struct virtqueue we're talking about.
*
* Enable the premapped mode of the vq.
*
* The vring in premapped mode does not do dma internally, so the driver must
* do dma mapping in advance. The driver must pass the dma_address through
* dma_address of scatterlist. When the driver got a used buffer from
* the vring, it has to unmap the dma address.
*
* This function must be called immediately after creating the vq, or after vq
* reset, and before adding any buffers to it.
*
* Caller must ensure we don't call this with other virtqueue operations
* at the same time (except where noted).
*
* Returns zero or a negative error.
* 0: success.
* -EINVAL: vring does not use the dma api, so we can not enable premapped mode.
*/
int virtqueue_set_dma_premapped(struct virtqueue *_vq, bool mode)
{
struct vring_virtqueue *vq = to_vvq(_vq);
u32 num;
START_USE(vq);
num = vq->packed_ring ? vq->packed.vring.num : vq->split.vring.num;
--> if (num != vq->vq.num_free) {
END_USE(vq);
return -EINVAL;
}
if (!vq->use_dma_api) {
END_USE(vq);
return -EINVAL;
}
if (mode) {
vq->premapped = true;
vq->do_unmap = false;
} else {
vq->premapped = false;
vq->do_unmap = vq->use_dma_api;
}
END_USE(vq);
return 0;
}
EXPORT_SYMBOL_GPL(virtqueue_set_dma_premapped);
>
>
> > --
> > 2.32.0.3.g01195cf9f
>
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Re: [PATCH vhost 01/22] virtio_ring: virtqueue_set_dma_premapped support disable
On Wed, Oct 11, 2023 at 05:27:07PM +0800, Xuan Zhuo wrote:
> virtqueue_set_dma_premapped() adds a new parameter to disable the
> virtqueue premapped mode.
>
> Signed-off-by: Xuan Zhuo
> ---
> drivers/net/virtio_net.c | 2 +-
> drivers/virtio/virtio_ring.c | 11 ---
> include/linux/virtio.h | 2 +-
> 3 files changed, 10 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index fe7f314d65c9..6b5f47ebf9b2 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -737,7 +737,7 @@ static void virtnet_rq_set_premapped(struct virtnet_info
> *vi)
> return;
>
> for (i = 0; i < vi->max_queue_pairs; i++) {
> - if (virtqueue_set_dma_premapped(vi->rq[i].vq))
> + if (virtqueue_set_dma_premapped(vi->rq[i].vq, true))
> continue;
>
> vi->rq[i].do_dma = true;
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index 51d8f3299c10..b3ded56722f4 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -2784,7 +2784,7 @@ EXPORT_SYMBOL_GPL(virtqueue_resize);
> * 0: success.
> * -EINVAL: vring does not use the dma api, so we can not enable premapped
> mode.
> */
> -int virtqueue_set_dma_premapped(struct virtqueue *_vq)
> +int virtqueue_set_dma_premapped(struct virtqueue *_vq, bool mode)
> {
> struct vring_virtqueue *vq = to_vvq(_vq);
> u32 num;
> @@ -2803,8 +2803,13 @@ int virtqueue_set_dma_premapped(struct virtqueue *_vq)
> return -EINVAL;
> }
>
> - vq->premapped = true;
> - vq->do_unmap = false;
> + if (mode) {
> + vq->premapped = true;
> + vq->do_unmap = false;
> + } else {
> + vq->premapped = false;
> + vq->do_unmap = vq->use_dma_api;
> + }
>
> END_USE(vq);
>
> diff --git a/include/linux/virtio.h b/include/linux/virtio.h
> index 4cc614a38376..1cf7b004348b 100644
> --- a/include/linux/virtio.h
> +++ b/include/linux/virtio.h
> @@ -81,7 +81,7 @@ bool virtqueue_enable_cb(struct virtqueue *vq);
>
> unsigned virtqueue_enable_cb_prepare(struct virtqueue *vq);
>
> -int virtqueue_set_dma_premapped(struct virtqueue *_vq);
> +int virtqueue_set_dma_premapped(struct virtqueue *_vq, bool mode);
>
> bool virtqueue_poll(struct virtqueue *vq, unsigned);
Wait a sec I thought we never change premapped. If you make this
dynamic don't you need a bunch of locking?
Or maybe queue is empty when you change this?
If yes pls add a bunch of BUG_ON checks to make sure this is not misused.
> --
> 2.32.0.3.g01195cf9f
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Re: [PATCH vhost 01/22] virtio_ring: virtqueue_set_dma_premapped support disable
Hi Xuan,
kernel test robot noticed the following build warnings:
[auto build test WARNING on linus/master]
[also build test WARNING on v6.6-rc5 next-20231011]
[cannot apply to mst-vhost/linux-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url:
https://github.com/intel-lab-lkp/linux/commits/Xuan-Zhuo/virtio_ring-virtqueue_set_dma_premapped-support-disable/20231011-180709
base: linus/master
patch link:
https://lore.kernel.org/r/20231011092728.105904-2-xuanzhuo%40linux.alibaba.com
patch subject: [PATCH vhost 01/22] virtio_ring: virtqueue_set_dma_premapped
support disable
config: m68k-allyesconfig
(https://download.01.org/0day-ci/archive/20231011/202310112204.h03tudph-...@intel.com/config)
compiler: m68k-linux-gcc (GCC) 13.2.0
reproduce (this is a W=1 build):
(https://download.01.org/0day-ci/archive/20231011/202310112204.h03tudph-...@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot
| Closes:
https://lore.kernel.org/oe-kbuild-all/202310112204.h03tudph-...@intel.com/
All warnings (new ones prefixed by >>):
>> drivers/virtio/virtio_ring.c:2788: warning: Function parameter or member
>> 'mode' not described in 'virtqueue_set_dma_premapped'
vim +2788 drivers/virtio/virtio_ring.c
c790e8e1817f1a Xuan Zhuo 2022-08-01 2765
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2766 /**
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2767 * virtqueue_set_dma_premapped - set
the vring premapped mode
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2768 * @_vq: the struct virtqueue we're
talking about.
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2769 *
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2770 * Enable the premapped mode of the
vq.
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2771 *
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2772 * The vring in premapped mode does
not do dma internally, so the driver must
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2773 * do dma mapping in advance. The
driver must pass the dma_address through
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2774 * dma_address of scatterlist. When
the driver got a used buffer from
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2775 * the vring, it has to unmap the
dma address.
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2776 *
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2777 * This function must be called
immediately after creating the vq, or after vq
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2778 * reset, and before adding any
buffers to it.
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2779 *
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2780 * Caller must ensure we don't call
this with other virtqueue operations
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2781 * at the same time (except where
noted).
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2782 *
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2783 * Returns zero or a negative error.
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2784 * 0: success.
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2785 * -EINVAL: vring does not use the
dma api, so we can not enable premapped mode.
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2786 */
f8d1a236ad114f Xuan Zhuo 2023-10-11 2787 int
virtqueue_set_dma_premapped(struct virtqueue *_vq, bool mode)
8daafe9ebbd21a Xuan Zhuo 2023-08-10 @2788 {
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2789 struct vring_virtqueue *vq =
to_vvq(_vq);
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2790 u32 num;
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2791
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2792 START_USE(vq);
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2793
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2794 num = vq->packed_ring ?
vq->packed.vring.num : vq->split.vring.num;
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2795
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2796 if (num != vq->vq.num_free) {
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2797 END_USE(vq);
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2798 return -EINVAL;
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2799 }
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2800
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2801 if (!vq->use_dma_api) {
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2802 END_USE(vq);
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2803 return -EINVAL;
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2804 }
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2805
f8d1a236ad114f Xuan Zhuo 2023-10-11 2806 if (mode) {
8daafe9ebbd21a Xuan Zhuo 2023-08-10 2807 vq->premapped = true;
b319940f83c21b Xuan Zhuo 2023-08-10 2808 vq->do_unmap = false;
f8d1a236ad114f Xuan Zhuo 2023-10-11 2809 } else {
f8d1a236ad114f Xuan Zhuo 2023-10-11 2810 vq->premapped = false;
f8d1a236ad114f Xuan Zhuo 2023-10-11 2811 vq->do_unmap
[PATCH vhost 01/22] virtio_ring: virtqueue_set_dma_premapped support disable
virtqueue_set_dma_premapped() adds a new parameter to disable the
virtqueue premapped mode.
Signed-off-by: Xuan Zhuo
---
drivers/net/virtio_net.c | 2 +-
drivers/virtio/virtio_ring.c | 11 ---
include/linux/virtio.h | 2 +-
3 files changed, 10 insertions(+), 5 deletions(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index fe7f314d65c9..6b5f47ebf9b2 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -737,7 +737,7 @@ static void virtnet_rq_set_premapped(struct virtnet_info
*vi)
return;
for (i = 0; i < vi->max_queue_pairs; i++) {
- if (virtqueue_set_dma_premapped(vi->rq[i].vq))
+ if (virtqueue_set_dma_premapped(vi->rq[i].vq, true))
continue;
vi->rq[i].do_dma = true;
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 51d8f3299c10..b3ded56722f4 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -2784,7 +2784,7 @@ EXPORT_SYMBOL_GPL(virtqueue_resize);
* 0: success.
* -EINVAL: vring does not use the dma api, so we can not enable premapped
mode.
*/
-int virtqueue_set_dma_premapped(struct virtqueue *_vq)
+int virtqueue_set_dma_premapped(struct virtqueue *_vq, bool mode)
{
struct vring_virtqueue *vq = to_vvq(_vq);
u32 num;
@@ -2803,8 +2803,13 @@ int virtqueue_set_dma_premapped(struct virtqueue *_vq)
return -EINVAL;
}
- vq->premapped = true;
- vq->do_unmap = false;
+ if (mode) {
+ vq->premapped = true;
+ vq->do_unmap = false;
+ } else {
+ vq->premapped = false;
+ vq->do_unmap = vq->use_dma_api;
+ }
END_USE(vq);
diff --git a/include/linux/virtio.h b/include/linux/virtio.h
index 4cc614a38376..1cf7b004348b 100644
--- a/include/linux/virtio.h
+++ b/include/linux/virtio.h
@@ -81,7 +81,7 @@ bool virtqueue_enable_cb(struct virtqueue *vq);
unsigned virtqueue_enable_cb_prepare(struct virtqueue *vq);
-int virtqueue_set_dma_premapped(struct virtqueue *_vq);
+int virtqueue_set_dma_premapped(struct virtqueue *_vq, bool mode);
bool virtqueue_poll(struct virtqueue *vq, unsigned);
--
2.32.0.3.g01195cf9f
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