RE: [PATCH v2 6/8] vfio: Change vfio_group_set_kvm() to vfio_file_set_kvm()

Tian, Kevin
2022-04-20T23:51:41Z

> From: Jason Gunthorpe <jgg@nvidia.com>
> Sent: Thursday, April 21, 2022 3:23 AM
>
> Just change the argument from struct vfio_group to struct file *.
>
> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Reviewed-by: Kevin Tian <kevin.tian@intel.com>

> ---
> drivers/vfio/vfio.c | 29 +++++++++++++++++++++--------
> include/linux/vfio.h | 5 +++--
> virt/kvm/vfio.c | 16 ++++++++--------
> 3 files changed, 32 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> index ae3e802991edf2..7d0fad02936f69 100644
> --- a/drivers/vfio/vfio.c
> +++ b/drivers/vfio/vfio.c
> @@ -2035,6 +2035,27 @@ bool vfio_file_enforced_coherent(struct file *file)
> }
> EXPORT_SYMBOL_GPL(vfio_file_enforced_coherent);
>
> +/**
> + * vfio_file_set_kvm - Link a kvm with VFIO drivers
> + * @file: VFIO group file
> + * @kvm: KVM to link
> + *
> + * The kvm pointer will be forwarded to all the vfio_device's attached to the
> + * VFIO file via the VFIO_GROUP_NOTIFY_SET_KVM notifier.
> + */
> +void vfio_file_set_kvm(struct file *file, struct kvm *kvm)
> +{
> + struct vfio_group *group = file->private_data;
> +
> + if (file->f_op != &vfio_group_fops)
> + return;
> +
> + group->kvm = kvm;
> + blocking_notifier_call_chain(&group->notifier,
> + VFIO_GROUP_NOTIFY_SET_KVM, kvm);
> +}
> +EXPORT_SYMBOL_GPL(vfio_file_set_kvm);
> +
> /*
> * Sub-module support
> */
> @@ -2446,14 +2467,6 @@ static int vfio_unregister_iommu_notifier(struct
> vfio_group *group,
> return ret;
> }
>
> -void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm)
> -{
> - group->kvm = kvm;
> - blocking_notifier_call_chain(&group->notifier,
> - VFIO_GROUP_NOTIFY_SET_KVM, kvm);
> -}
> -EXPORT_SYMBOL_GPL(vfio_group_set_kvm);
> -
> static int vfio_register_group_notifier(struct vfio_group *group,
> unsigned long *events,
> struct notifier_block *nb)
> diff --git a/include/linux/vfio.h b/include/linux/vfio.h
> index 7f022ae126a392..cbd9103b5c1223 100644
> --- a/include/linux/vfio.h
> +++ b/include/linux/vfio.h
> @@ -15,6 +15,8 @@
> #include <linux/poll.h>
> #include <uapi/linux/vfio.h>
>
> +struct kvm;
> +
> /*
> * VFIO devices can be placed in a set, this allows all devices to share this
> * structure and the VFIO core will provide a lock that is held around
> @@ -144,6 +146,7 @@ extern struct vfio_group
> *vfio_group_get_external_user_from_dev(struct device
> *dev);
> extern struct iommu_group *vfio_file_iommu_group(struct file *file);
> extern bool vfio_file_enforced_coherent(struct file *file);
> +extern void vfio_file_set_kvm(struct file *file, struct kvm *kvm);
>
> #define VFIO_PIN_PAGES_MAX_ENTRIES (PAGE_SIZE/sizeof(unsigned
> long))
>
> @@ -183,8 +186,6 @@ extern int vfio_unregister_notifier(struct device *dev,
> enum vfio_notify_type type,
> struct notifier_block *nb);
>
> -struct kvm;
> -extern void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm);
>
> /*
> * Sub-module helpers
> diff --git a/virt/kvm/vfio.c b/virt/kvm/vfio.c
> index 2330b0c272e671..2aeb53247001cc 100644
> --- a/virt/kvm/vfio.c
> +++ b/virt/kvm/vfio.c
> @@ -62,17 +62,17 @@ static void kvm_vfio_group_put_external_user(struct
> vfio_group *vfio_group)
> symbol_put(vfio_group_put_external_user);
> }
>
> -static void kvm_vfio_group_set_kvm(struct vfio_group *group, struct kvm
> *kvm)
> +static void kvm_vfio_file_set_kvm(struct file *file, struct kvm *kvm)
> {
> - void (*fn)(struct vfio_group *, struct kvm *);
> + void (*fn)(struct file *file, struct kvm *kvm);
>
> - fn = symbol_get(vfio_group_set_kvm);
> + fn = symbol_get(vfio_file_set_kvm);
> if (!fn)
> return;
>
> - fn(group, kvm);
> + fn(file, kvm);
>
> - symbol_put(vfio_group_set_kvm);
> + symbol_put(vfio_file_set_kvm);
> }
>
> static bool kvm_vfio_file_enforced_coherent(struct file *file)
> @@ -195,7 +195,7 @@ static int kvm_vfio_group_add(struct kvm_device
> *dev, unsigned int fd)
>
> mutex_unlock(&kv->lock);
>
> - kvm_vfio_group_set_kvm(vfio_group, dev->kvm);
> + kvm_vfio_file_set_kvm(kvg->file, dev->kvm);
> kvm_vfio_update_coherency(dev);
>
> return 0;
> @@ -231,7 +231,7 @@ static int kvm_vfio_group_del(struct kvm_device
> *dev, unsigned int fd)
> #ifdef CONFIG_SPAPR_TCE_IOMMU
> kvm_spapr_tce_release_vfio_group(dev->kvm, kvg);
> #endif
> - kvm_vfio_group_set_kvm(kvg->vfio_group, NULL);
> + kvm_vfio_file_set_kvm(kvg->file, NULL);
> kvm_vfio_group_put_external_user(kvg->vfio_group);
> fput(kvg->file);
> kfree(kvg);
> @@ -358,7 +358,7 @@ static void kvm_vfio_destroy(struct kvm_device *dev)
> #ifdef CONFIG_SPAPR_TCE_IOMMU
> kvm_spapr_tce_release_vfio_group(dev->kvm, kvg);
> #endif
> - kvm_vfio_group_set_kvm(kvg->vfio_group, NULL);
> + kvm_vfio_file_set_kvm(kvg->file, NULL);
> kvm_vfio_group_put_external_user(kvg->vfio_group);
> fput(kvg->file);
> list_del(&kvg->node);
> --
> 2.36.0