On Sun, 2014-11-23 at 19:35 +0100, Eric Auger wrote: > Provide wrapper functions that allow KVM-VFIO device code to > interact with a vfio device: > - kvm_vfio_device_get_external_user gets a handle to a struct > vfio_device from the vfio device file descriptor and increments > its reference counter, > - kvm_vfio_device_put_external_user decrements the reference counter > to a vfio device, > - kvm_vfio_external_base_device returns a handle to the struct device > of the vfio device. > > The KVM-VFIO device uses the VFIO external API device functions. > > Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx> > > --- > > v2 -> v3: > reword the commit message and title > > v1 -> v2: > - kvm_vfio_external_get_base_device renamed into > kvm_vfio_external_base_device > - kvm_vfio_external_get_type removed > --- > arch/arm/include/asm/kvm_host.h | 5 +++++ > virt/kvm/vfio.c | 45 +++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 50 insertions(+) > > diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h > index 53036e2..bca5b79 100644 > --- a/arch/arm/include/asm/kvm_host.h > +++ b/arch/arm/include/asm/kvm_host.h > @@ -169,6 +169,11 @@ void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte); > unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu); > int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices); > > +struct vfio_device; > +struct vfio_device *kvm_vfio_device_get_external_user(struct file *filep); > +void kvm_vfio_device_put_external_user(struct vfio_device *vdev); > +struct device *kvm_vfio_external_base_device(struct vfio_device *vdev); > + This doesn't look right, why doesn't kvm-vfio send the struct dev to the arch callback? Then the below functions can be static. Nothing outside of kvm-vfio device should need to do anything with vfio_device references. > /* We do not have shadow page tables, hence the empty hooks */ > static inline int kvm_age_hva(struct kvm *kvm, unsigned long start, > unsigned long end) > diff --git a/virt/kvm/vfio.c b/virt/kvm/vfio.c > index 620e37f..6f0cc34 100644 > --- a/virt/kvm/vfio.c > +++ b/virt/kvm/vfio.c > @@ -60,6 +60,51 @@ static void kvm_vfio_group_put_external_user(struct vfio_group *vfio_group) > symbol_put(vfio_group_put_external_user); > } > > +struct vfio_device *kvm_vfio_device_get_external_user(struct file *filep) > +{ > + struct vfio_device *vdev; > + struct vfio_device *(*fn)(struct file *); > + > + fn = symbol_get(vfio_device_get_external_user); > + if (!fn) > + return ERR_PTR(-EINVAL); > + > + vdev = fn(filep); > + > + symbol_put(vfio_device_get_external_user); > + > + return vdev; > +} > + > +void kvm_vfio_device_put_external_user(struct vfio_device *vdev) > +{ > + void (*fn)(struct vfio_device *); > + > + fn = symbol_get(vfio_device_put_external_user); > + if (!fn) > + return; > + > + fn(vdev); > + > + symbol_put(vfio_device_put_external_user); > +} > + > +struct device *kvm_vfio_external_base_device(struct vfio_device *vdev) > +{ > + struct device *(*fn)(struct vfio_device *); > + struct device *dev; > + > + fn = symbol_get(vfio_external_base_device); > + if (!fn) > + return NULL; > + > + dev = fn(vdev); > + > + symbol_put(vfio_external_base_device); > + > + return dev; > +} > + > static bool kvm_vfio_group_is_coherent(struct vfio_group *vfio_group) > { > long (*fn)(struct vfio_group *, unsigned long); -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html