| Message ID | 20230916003118.2540661-5-seanjc@google.com (mailing list archive) |
|---|---|
| State | Handled Elsewhere |
| Headers | show |
| Series | KVM: vfio: Hide KVM internals from others | expand |
| Context | Check | Description |
|---|---|---|
| conchuod/cover_letter | success | Series has a cover letter |
| conchuod/tree_selection | success | Guessed tree name to be for-next at HEAD 0bb80ecc33a8 |
| conchuod/fixes_present | success | Fixes tag not required for -next series |
| conchuod/maintainers_pattern | success | MAINTAINERS pattern errors before the patch: 5 and now 5 |
| conchuod/verify_signedoff | success | Signed-off-by tag matches author and committer |
| conchuod/kdoc | success | Errors and warnings before: 13 this patch: 13 |
| conchuod/build_rv64_clang_allmodconfig | success | Errors and warnings before: 9 this patch: 9 |
| conchuod/module_param | success | Was 0 now: 0 |
| conchuod/build_rv64_gcc_allmodconfig | success | Errors and warnings before: 9 this patch: 9 |
| conchuod/build_rv32_defconfig | success | Build OK |
| conchuod/dtb_warn_rv64 | success | Errors and warnings before: 25 this patch: 25 |
| conchuod/header_inline | success | No static functions without inline keyword in header files |
| conchuod/checkpatch | warning | CHECK: spinlock_t definition without comment |
| conchuod/build_rv64_nommu_k210_defconfig | success | Build OK |
| conchuod/verify_fixes | success | No Fixes tag |
| conchuod/build_rv64_nommu_virt_defconfig | success | Build OK |
On Fri, 15 Sep 2023 17:30:56 -0700 Sean Christopherson <seanjc@google.com> wrote: > Add a struct to hold the KVM assets need to manage and pass along KVM > references to VFIO devices. Providing a common struct deduplicates the > group vs. iommufd code, and will make it easier to rework the attachment > logic so that VFIO doesn't have to do a symbol lookup to retrieve the > get/put helpers from KVM. > > Signed-off-by: Sean Christopherson <seanjc@google.com> > --- > drivers/vfio/device_cdev.c | 9 +------- > drivers/vfio/group.c | 18 ++-------------- > drivers/vfio/vfio.h | 22 +++++++++---------- > drivers/vfio/vfio_main.c | 43 +++++++++++++++++++++++++++----------- > 4 files changed, 45 insertions(+), 47 deletions(-) Reviewed-by: Alex Williamson <alex.williamson@redhat.com> > diff --git a/drivers/vfio/device_cdev.c b/drivers/vfio/device_cdev.c > index e75da0a70d1f..e484d6d6400a 100644 > --- a/drivers/vfio/device_cdev.c > +++ b/drivers/vfio/device_cdev.c > @@ -46,13 +46,6 @@ int vfio_device_fops_cdev_open(struct inode *inode, struct file *filep) > return ret; > } > > -static void vfio_df_get_kvm_safe(struct vfio_device_file *df) > -{ > - spin_lock(&df->kvm_ref_lock); > - vfio_device_get_kvm_safe(df->device, df->kvm); > - spin_unlock(&df->kvm_ref_lock); > -} > - > long vfio_df_ioctl_bind_iommufd(struct vfio_device_file *df, > struct vfio_device_bind_iommufd __user *arg) > { > @@ -99,7 +92,7 @@ long vfio_df_ioctl_bind_iommufd(struct vfio_device_file *df, > * a reference. This reference is held until device closed. > * Save the pointer in the device for use by drivers. > */ > - vfio_df_get_kvm_safe(df); > + vfio_device_get_kvm_safe(df->device, &df->kvm_ref); > > ret = vfio_df_open(df); > if (ret) > diff --git a/drivers/vfio/group.c b/drivers/vfio/group.c > index 610a429c6191..756e47ff4cf0 100644 > --- a/drivers/vfio/group.c > +++ b/drivers/vfio/group.c > @@ -157,13 +157,6 @@ static int vfio_group_ioctl_set_container(struct vfio_group *group, > return ret; > } > > -static void vfio_device_group_get_kvm_safe(struct vfio_device *device) > -{ > - spin_lock(&device->group->kvm_ref_lock); > - vfio_device_get_kvm_safe(device, device->group->kvm); > - spin_unlock(&device->group->kvm_ref_lock); > -} > - > static int vfio_df_group_open(struct vfio_device_file *df) > { > struct vfio_device *device = df->device; > @@ -184,7 +177,7 @@ static int vfio_df_group_open(struct vfio_device_file *df) > * the pointer in the device for use by drivers. > */ > if (device->open_count == 0) > - vfio_device_group_get_kvm_safe(device); > + vfio_device_get_kvm_safe(device, &device->group->kvm_ref); > > df->iommufd = device->group->iommufd; > if (df->iommufd && vfio_device_is_noiommu(device) && device->open_count == 0) { > @@ -560,7 +553,7 @@ static struct vfio_group *vfio_group_alloc(struct iommu_group *iommu_group, > > refcount_set(&group->drivers, 1); > mutex_init(&group->group_lock); > - spin_lock_init(&group->kvm_ref_lock); > + spin_lock_init(&group->kvm_ref.lock); > INIT_LIST_HEAD(&group->device_list); > mutex_init(&group->device_lock); > group->iommu_group = iommu_group; > @@ -884,13 +877,6 @@ bool vfio_group_enforced_coherent(struct vfio_group *group) > return ret; > } > > -void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm) > -{ > - spin_lock(&group->kvm_ref_lock); > - group->kvm = kvm; > - spin_unlock(&group->kvm_ref_lock); > -} > - > /** > * vfio_file_has_dev - True if the VFIO file is a handle for device > * @file: VFIO file to check > diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h > index c26d1ad68105..a1f741365075 100644 > --- a/drivers/vfio/vfio.h > +++ b/drivers/vfio/vfio.h > @@ -12,18 +12,23 @@ > #include <linux/module.h> > #include <linux/vfio.h> > > +struct kvm; > struct iommufd_ctx; > struct iommu_group; > struct vfio_container; > > +struct vfio_kvm_reference { > + struct kvm *kvm; > + spinlock_t lock; > +}; > + > struct vfio_device_file { > struct vfio_device *device; > struct vfio_group *group; > > u8 access_granted; > u32 devid; /* only valid when iommufd is valid */ > - spinlock_t kvm_ref_lock; /* protect kvm field */ > - struct kvm *kvm; > + struct vfio_kvm_reference kvm_ref; > struct iommufd_ctx *iommufd; /* protected by struct vfio_device_set::lock */ > }; > > @@ -88,11 +93,10 @@ struct vfio_group { > #endif > enum vfio_group_type type; > struct mutex group_lock; > - struct kvm *kvm; > + struct vfio_kvm_reference kvm_ref; > struct file *opened_file; > struct blocking_notifier_head notifier; > struct iommufd_ctx *iommufd; > - spinlock_t kvm_ref_lock; > unsigned int cdev_device_open_cnt; > }; > > @@ -108,7 +112,6 @@ void vfio_device_group_unuse_iommu(struct vfio_device *device); > void vfio_df_group_close(struct vfio_device_file *df); > struct vfio_group *vfio_group_from_file(struct file *file); > bool vfio_group_enforced_coherent(struct vfio_group *group); > -void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm); > bool vfio_device_has_container(struct vfio_device *device); > int __init vfio_group_init(void); > void vfio_group_cleanup(void); > @@ -171,10 +174,6 @@ static inline bool vfio_group_enforced_coherent(struct vfio_group *group) > return true; > } > > -static inline void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm) > -{ > -} > - > static inline bool vfio_device_has_container(struct vfio_device *device) > { > return false; > @@ -435,11 +434,12 @@ static inline void vfio_virqfd_exit(void) > #endif > > #if IS_ENABLED(CONFIG_KVM) > -void vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm); > +void vfio_device_get_kvm_safe(struct vfio_device *device, > + struct vfio_kvm_reference *ref); > void vfio_device_put_kvm(struct vfio_device *device); > #else > static inline void vfio_device_get_kvm_safe(struct vfio_device *device, > - struct kvm *kvm) > + struct vfio_kvm_reference *ref) > { > } > > diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c > index 124cc88966a7..e77e8c6aae2f 100644 > --- a/drivers/vfio/vfio_main.c > +++ b/drivers/vfio/vfio_main.c > @@ -397,7 +397,7 @@ vfio_allocate_device_file(struct vfio_device *device) > return ERR_PTR(-ENOMEM); > > df->device = device; > - spin_lock_init(&df->kvm_ref_lock); > + spin_lock_init(&df->kvm_ref.lock); > > return df; > } > @@ -1303,7 +1303,8 @@ bool vfio_file_enforced_coherent(struct file *file) > EXPORT_SYMBOL_GPL(vfio_file_enforced_coherent); > > #if IS_ENABLED(CONFIG_KVM) > -void vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm) > +void vfio_device_get_kvm_safe(struct vfio_device *device, > + struct vfio_kvm_reference *ref) > { > void (*pfn)(struct kvm *kvm); > bool (*fn)(struct kvm *kvm); > @@ -1311,28 +1312,33 @@ void vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm) > > lockdep_assert_held(&device->dev_set->lock); > > - if (!kvm) > - return; > + spin_lock(&ref->lock); > + > + if (!ref->kvm) > + goto out; > > pfn = symbol_get(kvm_put_kvm); > if (WARN_ON(!pfn)) > - return; > + goto out; > > fn = symbol_get(kvm_get_kvm_safe); > if (WARN_ON(!fn)) { > symbol_put(kvm_put_kvm); > - return; > + goto out; > } > > - ret = fn(kvm); > + ret = fn(ref->kvm); > symbol_put(kvm_get_kvm_safe); > if (!ret) { > symbol_put(kvm_put_kvm); > - return; > + goto out; > } > > device->put_kvm = pfn; > - device->kvm = kvm; > + device->kvm = ref->kvm; > + > +out: > + spin_unlock(&ref->lock); > } > > void vfio_device_put_kvm(struct vfio_device *device) > @@ -1353,6 +1359,21 @@ void vfio_device_put_kvm(struct vfio_device *device) > device->kvm = NULL; > } > > +static void vfio_device_set_kvm(struct vfio_kvm_reference *ref, > + struct kvm *kvm) > +{ > + spin_lock(&ref->lock); > + ref->kvm = kvm; > + spin_unlock(&ref->lock); > +} > + > +static void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm) > +{ > +#if IS_ENABLED(CONFIG_VFIO_GROUP) > + vfio_device_set_kvm(&group->kvm_ref, kvm); > +#endif > +} > + > static void vfio_device_file_set_kvm(struct file *file, struct kvm *kvm) > { > struct vfio_device_file *df = file->private_data; > @@ -1362,9 +1383,7 @@ static void vfio_device_file_set_kvm(struct file *file, struct kvm *kvm) > * be propagated to vfio_device::kvm when the file is bound to > * iommufd successfully in the vfio device cdev path. > */ > - spin_lock(&df->kvm_ref_lock); > - df->kvm = kvm; > - spin_unlock(&df->kvm_ref_lock); > + vfio_device_set_kvm(&df->kvm_ref, kvm); > } > > /**
diff --git a/drivers/vfio/device_cdev.c b/drivers/vfio/device_cdev.c index e75da0a70d1f..e484d6d6400a 100644 --- a/drivers/vfio/device_cdev.c +++ b/drivers/vfio/device_cdev.c @@ -46,13 +46,6 @@ int vfio_device_fops_cdev_open(struct inode *inode, struct file *filep) return ret; } -static void vfio_df_get_kvm_safe(struct vfio_device_file *df) -{ - spin_lock(&df->kvm_ref_lock); - vfio_device_get_kvm_safe(df->device, df->kvm); - spin_unlock(&df->kvm_ref_lock); -} - long vfio_df_ioctl_bind_iommufd(struct vfio_device_file *df, struct vfio_device_bind_iommufd __user *arg) { @@ -99,7 +92,7 @@ long vfio_df_ioctl_bind_iommufd(struct vfio_device_file *df, * a reference. This reference is held until device closed. * Save the pointer in the device for use by drivers. */ - vfio_df_get_kvm_safe(df); + vfio_device_get_kvm_safe(df->device, &df->kvm_ref); ret = vfio_df_open(df); if (ret) diff --git a/drivers/vfio/group.c b/drivers/vfio/group.c index 610a429c6191..756e47ff4cf0 100644 --- a/drivers/vfio/group.c +++ b/drivers/vfio/group.c @@ -157,13 +157,6 @@ static int vfio_group_ioctl_set_container(struct vfio_group *group, return ret; } -static void vfio_device_group_get_kvm_safe(struct vfio_device *device) -{ - spin_lock(&device->group->kvm_ref_lock); - vfio_device_get_kvm_safe(device, device->group->kvm); - spin_unlock(&device->group->kvm_ref_lock); -} - static int vfio_df_group_open(struct vfio_device_file *df) { struct vfio_device *device = df->device; @@ -184,7 +177,7 @@ static int vfio_df_group_open(struct vfio_device_file *df) * the pointer in the device for use by drivers. */ if (device->open_count == 0) - vfio_device_group_get_kvm_safe(device); + vfio_device_get_kvm_safe(device, &device->group->kvm_ref); df->iommufd = device->group->iommufd; if (df->iommufd && vfio_device_is_noiommu(device) && device->open_count == 0) { @@ -560,7 +553,7 @@ static struct vfio_group *vfio_group_alloc(struct iommu_group *iommu_group, refcount_set(&group->drivers, 1); mutex_init(&group->group_lock); - spin_lock_init(&group->kvm_ref_lock); + spin_lock_init(&group->kvm_ref.lock); INIT_LIST_HEAD(&group->device_list); mutex_init(&group->device_lock); group->iommu_group = iommu_group; @@ -884,13 +877,6 @@ bool vfio_group_enforced_coherent(struct vfio_group *group) return ret; } -void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm) -{ - spin_lock(&group->kvm_ref_lock); - group->kvm = kvm; - spin_unlock(&group->kvm_ref_lock); -} - /** * vfio_file_has_dev - True if the VFIO file is a handle for device * @file: VFIO file to check diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h index c26d1ad68105..a1f741365075 100644 --- a/drivers/vfio/vfio.h +++ b/drivers/vfio/vfio.h @@ -12,18 +12,23 @@ #include <linux/module.h> #include <linux/vfio.h> +struct kvm; struct iommufd_ctx; struct iommu_group; struct vfio_container; +struct vfio_kvm_reference { + struct kvm *kvm; + spinlock_t lock; +}; + struct vfio_device_file { struct vfio_device *device; struct vfio_group *group; u8 access_granted; u32 devid; /* only valid when iommufd is valid */ - spinlock_t kvm_ref_lock; /* protect kvm field */ - struct kvm *kvm; + struct vfio_kvm_reference kvm_ref; struct iommufd_ctx *iommufd; /* protected by struct vfio_device_set::lock */ }; @@ -88,11 +93,10 @@ struct vfio_group { #endif enum vfio_group_type type; struct mutex group_lock; - struct kvm *kvm; + struct vfio_kvm_reference kvm_ref; struct file *opened_file; struct blocking_notifier_head notifier; struct iommufd_ctx *iommufd; - spinlock_t kvm_ref_lock; unsigned int cdev_device_open_cnt; }; @@ -108,7 +112,6 @@ void vfio_device_group_unuse_iommu(struct vfio_device *device); void vfio_df_group_close(struct vfio_device_file *df); struct vfio_group *vfio_group_from_file(struct file *file); bool vfio_group_enforced_coherent(struct vfio_group *group); -void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm); bool vfio_device_has_container(struct vfio_device *device); int __init vfio_group_init(void); void vfio_group_cleanup(void); @@ -171,10 +174,6 @@ static inline bool vfio_group_enforced_coherent(struct vfio_group *group) return true; } -static inline void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm) -{ -} - static inline bool vfio_device_has_container(struct vfio_device *device) { return false; @@ -435,11 +434,12 @@ static inline void vfio_virqfd_exit(void) #endif #if IS_ENABLED(CONFIG_KVM) -void vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm); +void vfio_device_get_kvm_safe(struct vfio_device *device, + struct vfio_kvm_reference *ref); void vfio_device_put_kvm(struct vfio_device *device); #else static inline void vfio_device_get_kvm_safe(struct vfio_device *device, - struct kvm *kvm) + struct vfio_kvm_reference *ref) { } diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c index 124cc88966a7..e77e8c6aae2f 100644 --- a/drivers/vfio/vfio_main.c +++ b/drivers/vfio/vfio_main.c @@ -397,7 +397,7 @@ vfio_allocate_device_file(struct vfio_device *device) return ERR_PTR(-ENOMEM); df->device = device; - spin_lock_init(&df->kvm_ref_lock); + spin_lock_init(&df->kvm_ref.lock); return df; } @@ -1303,7 +1303,8 @@ bool vfio_file_enforced_coherent(struct file *file) EXPORT_SYMBOL_GPL(vfio_file_enforced_coherent); #if IS_ENABLED(CONFIG_KVM) -void vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm) +void vfio_device_get_kvm_safe(struct vfio_device *device, + struct vfio_kvm_reference *ref) { void (*pfn)(struct kvm *kvm); bool (*fn)(struct kvm *kvm); @@ -1311,28 +1312,33 @@ void vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm) lockdep_assert_held(&device->dev_set->lock); - if (!kvm) - return; + spin_lock(&ref->lock); + + if (!ref->kvm) + goto out; pfn = symbol_get(kvm_put_kvm); if (WARN_ON(!pfn)) - return; + goto out; fn = symbol_get(kvm_get_kvm_safe); if (WARN_ON(!fn)) { symbol_put(kvm_put_kvm); - return; + goto out; } - ret = fn(kvm); + ret = fn(ref->kvm); symbol_put(kvm_get_kvm_safe); if (!ret) { symbol_put(kvm_put_kvm); - return; + goto out; } device->put_kvm = pfn; - device->kvm = kvm; + device->kvm = ref->kvm; + +out: + spin_unlock(&ref->lock); } void vfio_device_put_kvm(struct vfio_device *device) @@ -1353,6 +1359,21 @@ void vfio_device_put_kvm(struct vfio_device *device) device->kvm = NULL; } +static void vfio_device_set_kvm(struct vfio_kvm_reference *ref, + struct kvm *kvm) +{ + spin_lock(&ref->lock); + ref->kvm = kvm; + spin_unlock(&ref->lock); +} + +static void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm) +{ +#if IS_ENABLED(CONFIG_VFIO_GROUP) + vfio_device_set_kvm(&group->kvm_ref, kvm); +#endif +} + static void vfio_device_file_set_kvm(struct file *file, struct kvm *kvm) { struct vfio_device_file *df = file->private_data; @@ -1362,9 +1383,7 @@ static void vfio_device_file_set_kvm(struct file *file, struct kvm *kvm) * be propagated to vfio_device::kvm when the file is bound to * iommufd successfully in the vfio device cdev path. */ - spin_lock(&df->kvm_ref_lock); - df->kvm = kvm; - spin_unlock(&df->kvm_ref_lock); + vfio_device_set_kvm(&df->kvm_ref, kvm); } /**
Add a struct to hold the KVM assets need to manage and pass along KVM references to VFIO devices. Providing a common struct deduplicates the group vs. iommufd code, and will make it easier to rework the attachment logic so that VFIO doesn't have to do a symbol lookup to retrieve the get/put helpers from KVM. Signed-off-by: Sean Christopherson <seanjc@google.com> --- drivers/vfio/device_cdev.c | 9 +------- drivers/vfio/group.c | 18 ++-------------- drivers/vfio/vfio.h | 22 +++++++++---------- drivers/vfio/vfio_main.c | 43 +++++++++++++++++++++++++++----------- 4 files changed, 45 insertions(+), 47 deletions(-)