| Message ID | 20241105072642.898710-8-lulu@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | vhost: Add support of kthread API | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
On Tue, Nov 5, 2024 at 3:28 PM Cindy Lu <lulu@redhat.com> wrote: > > Add a new UAPI to enable setting the vhost device to task mode. > The userspace application can use VHOST_SET_INHERIT_FROM_OWNER > to configure the mode if necessary. > This setting must be applied before VHOST_SET_OWNER, as the worker > will be created in the VHOST_SET_OWNER function > > Signed-off-by: Cindy Lu <lulu@redhat.com> > --- > drivers/vhost/vhost.c | 15 ++++++++++++++- > include/uapi/linux/vhost.h | 2 ++ > 2 files changed, 16 insertions(+), 1 deletion(-) > > diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c > index c17dc01febcc..70c793b63905 100644 > --- a/drivers/vhost/vhost.c > +++ b/drivers/vhost/vhost.c > @@ -2274,8 +2274,9 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) > { > struct eventfd_ctx *ctx; > u64 p; > - long r; > + long r = 0; > int i, fd; > + bool inherit_owner; > > /* If you are not the owner, you can become one */ > if (ioctl == VHOST_SET_OWNER) { > @@ -2332,6 +2333,18 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) > if (ctx) > eventfd_ctx_put(ctx); > break; > + case VHOST_SET_INHERIT_FROM_OWNER: > + /*inherit_owner can only be modified before owner is set*/ > + if (vhost_dev_has_owner(d)) > + break; > + > + if (copy_from_user(&inherit_owner, argp, > + sizeof(inherit_owner))) { > + r = -EFAULT; > + break; > + } > + d->inherit_owner = inherit_owner; > + break; Is there any case that we need to switch from owner back to kthread? If not I would choose a more simplified API that is just VHOST_INHERIT_OWNER. > default: > r = -ENOIOCTLCMD; > break; > diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h > index b95dd84eef2d..1e192038633d 100644 > --- a/include/uapi/linux/vhost.h > +++ b/include/uapi/linux/vhost.h > @@ -235,4 +235,6 @@ > */ > #define VHOST_VDPA_GET_VRING_SIZE _IOWR(VHOST_VIRTIO, 0x82, \ > struct vhost_vring_state) > + > +#define VHOST_SET_INHERIT_FROM_OWNER _IOW(VHOST_VIRTIO, 0x83, bool) > #endif > -- > 2.45.0 Thanks >
On Tue, Nov 05, 2024 at 03:25:26PM +0800, Cindy Lu wrote: >Add a new UAPI to enable setting the vhost device to task mode. >The userspace application can use VHOST_SET_INHERIT_FROM_OWNER >to configure the mode if necessary. >This setting must be applied before VHOST_SET_OWNER, as the worker >will be created in the VHOST_SET_OWNER function > >Signed-off-by: Cindy Lu <lulu@redhat.com> >--- > drivers/vhost/vhost.c | 15 ++++++++++++++- > include/uapi/linux/vhost.h | 2 ++ > 2 files changed, 16 insertions(+), 1 deletion(-) > >diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c >index c17dc01febcc..70c793b63905 100644 >--- a/drivers/vhost/vhost.c >+++ b/drivers/vhost/vhost.c >@@ -2274,8 +2274,9 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) > { > struct eventfd_ctx *ctx; > u64 p; >- long r; >+ long r = 0; I don't know if something is missing in this patch, but I am confused: `r` is set few lines below... > int i, fd; >+ bool inherit_owner; > > /* If you are not the owner, you can become one */ > if (ioctl == VHOST_SET_OWNER) { ... /* You must be the owner to do anything else */ r = vhost_dev_check_owner(d); if (r) goto done; So, why we are now initializing it to 0? >@@ -2332,6 +2333,18 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) > if (ctx) > eventfd_ctx_put(ctx); > break; >+ case VHOST_SET_INHERIT_FROM_OWNER: >+ /*inherit_owner can only be modified before owner is set*/ >+ if (vhost_dev_has_owner(d)) And here, how this check can be false, if at the beginning of the function we call vhost_dev_check_owner()? Maybe your intention was to add this code before the `vhost_dev_check_owner()` call, so this should explain why initialize `r` to 0, but I'm not sure. >+ break; Should we return an error (e.g. -EPERM) in this case? >+ >+ if (copy_from_user(&inherit_owner, argp, >+ sizeof(inherit_owner))) { >+ r = -EFAULT; >+ break; >+ } >+ d->inherit_owner = inherit_owner; >+ break; > default: > r = -ENOIOCTLCMD; > break; >diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h >index b95dd84eef2d..1e192038633d 100644 >--- a/include/uapi/linux/vhost.h >+++ b/include/uapi/linux/vhost.h >@@ -235,4 +235,6 @@ > */ > #define VHOST_VDPA_GET_VRING_SIZE _IOWR(VHOST_VIRTIO, 0x82, \ > struct vhost_vring_state) >+ Please add a documentation here, this is UAPI, so the user should know what this ioctl does based on the parameter. Thanks, Stefano >+#define VHOST_SET_INHERIT_FROM_OWNER _IOW(VHOST_VIRTIO, 0x83, bool) > #endif >-- >2.45.0 >
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index c17dc01febcc..70c793b63905 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -2274,8 +2274,9 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) { struct eventfd_ctx *ctx; u64 p; - long r; + long r = 0; int i, fd; + bool inherit_owner; /* If you are not the owner, you can become one */ if (ioctl == VHOST_SET_OWNER) { @@ -2332,6 +2333,18 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) if (ctx) eventfd_ctx_put(ctx); break; + case VHOST_SET_INHERIT_FROM_OWNER: + /*inherit_owner can only be modified before owner is set*/ + if (vhost_dev_has_owner(d)) + break; + + if (copy_from_user(&inherit_owner, argp, + sizeof(inherit_owner))) { + r = -EFAULT; + break; + } + d->inherit_owner = inherit_owner; + break; default: r = -ENOIOCTLCMD; break; diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h index b95dd84eef2d..1e192038633d 100644 --- a/include/uapi/linux/vhost.h +++ b/include/uapi/linux/vhost.h @@ -235,4 +235,6 @@ */ #define VHOST_VDPA_GET_VRING_SIZE _IOWR(VHOST_VIRTIO, 0x82, \ struct vhost_vring_state) + +#define VHOST_SET_INHERIT_FROM_OWNER _IOW(VHOST_VIRTIO, 0x83, bool) #endif
Add a new UAPI to enable setting the vhost device to task mode. The userspace application can use VHOST_SET_INHERIT_FROM_OWNER to configure the mode if necessary. This setting must be applied before VHOST_SET_OWNER, as the worker will be created in the VHOST_SET_OWNER function Signed-off-by: Cindy Lu <lulu@redhat.com> --- drivers/vhost/vhost.c | 15 ++++++++++++++- include/uapi/linux/vhost.h | 2 ++ 2 files changed, 16 insertions(+), 1 deletion(-)