From: Zhenyu Wang Date: Fri, 7 Dec 2018 08:16:53 +0000 (+0800) Subject: drm/i915/gvt: Change KVMGT as self load module X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=9bdb073464d6008ed1839d358e320108ed12daae;p=openwrt%2Fstaging%2Fblogic.git drm/i915/gvt: Change KVMGT as self load module This trys to make 'kvmgt' module as self loadable instead of loading by i915/gvt device model. So hypervisor specific module could be stand-alone, e.g only after loading hypervisor specific module, GVT feature could be enabled via specific hypervisor interface, e.g VFIO/mdev. So this trys to use hypervisor module register/unregister interface for that. Hypervisor module needs to take care of module reference itself when working for hypervisor interface, e.g for VFIO/mdev, hypervisor module would reference counting mdev when open and release. This makes 'kvmgt' module really split from GVT device model. User needs to load 'kvmgt' to enable VFIO/mdev interface. v6: - remove unused variable v5: - put module reference in register error path v4: - fix checkpatch warning v3: - Fix module reference handling for device open and release. Unused mdev devices would be cleaned up in device unregister when module unload. v2: - Fix kvmgt order after i915 for built-in case Cc: "Yuan, Hang" Cc: Alex Williamson Cc: "He, Min" Reviewed-by: Yuan, Hang Acked-by: Joonas Lahtinen Signed-off-by: Zhenyu Wang --- diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile index 19b5fe5016bf..63893fe00711 100644 --- a/drivers/gpu/drm/i915/Makefile +++ b/drivers/gpu/drm/i915/Makefile @@ -198,3 +198,4 @@ endif i915-y += intel_lpe_audio.o obj-$(CONFIG_DRM_I915) += i915.o +obj-$(CONFIG_DRM_I915_GVT_KVMGT) += gvt/kvmgt.o diff --git a/drivers/gpu/drm/i915/gvt/Makefile b/drivers/gpu/drm/i915/gvt/Makefile index b016dc753db9..271fb46d4dd0 100644 --- a/drivers/gpu/drm/i915/gvt/Makefile +++ b/drivers/gpu/drm/i915/gvt/Makefile @@ -7,4 +7,3 @@ GVT_SOURCE := gvt.o aperture_gm.o handlers.o vgpu.o trace_points.o firmware.o \ ccflags-y += -I$(src) -I$(src)/$(GVT_DIR) i915-y += $(addprefix $(GVT_DIR)/, $(GVT_SOURCE)) -obj-$(CONFIG_DRM_I915_GVT_KVMGT) += $(GVT_DIR)/kvmgt.o diff --git a/drivers/gpu/drm/i915/gvt/gvt.c b/drivers/gpu/drm/i915/gvt/gvt.c index a5b760b7bc10..4e8947f33bd0 100644 --- a/drivers/gpu/drm/i915/gvt/gvt.c +++ b/drivers/gpu/drm/i915/gvt/gvt.c @@ -187,52 +187,6 @@ static const struct intel_gvt_ops intel_gvt_ops = { .write_protect_handler = intel_vgpu_page_track_handler, }; -/** - * intel_gvt_init_host - Load MPT modules and detect if we're running in host - * - * This function is called at the driver loading stage. If failed to find a - * loadable MPT module or detect currently we're running in a VM, then GVT-g - * will be disabled - * - * Returns: - * Zero on success, negative error code if failed. - * - */ -int intel_gvt_init_host(void) -{ - if (intel_gvt_host.initialized) - return 0; - - /* Xen DOM U */ - if (xen_domain() && !xen_initial_domain()) - return -ENODEV; - - /* Try to load MPT modules for hypervisors */ - if (xen_initial_domain()) { - /* In Xen dom0 */ - intel_gvt_host.mpt = try_then_request_module( - symbol_get(xengt_mpt), "xengt"); - intel_gvt_host.hypervisor_type = INTEL_GVT_HYPERVISOR_XEN; - } else { -#if IS_ENABLED(CONFIG_DRM_I915_GVT_KVMGT) - /* not in Xen. Try KVMGT */ - intel_gvt_host.mpt = try_then_request_module( - symbol_get(kvmgt_mpt), "kvmgt"); - intel_gvt_host.hypervisor_type = INTEL_GVT_HYPERVISOR_KVM; -#endif - } - - /* Fail to load MPT modules - bail out */ - if (!intel_gvt_host.mpt) - return -EINVAL; - - gvt_dbg_core("Running with hypervisor %s in host mode\n", - supported_hypervisors[intel_gvt_host.hypervisor_type]); - - intel_gvt_host.initialized = true; - return 0; -} - static void init_device_info(struct intel_gvt *gvt) { struct intel_gvt_device_info *info = &gvt->device_info; @@ -316,7 +270,6 @@ void intel_gvt_clean_device(struct drm_i915_private *dev_priv) return; intel_gvt_destroy_idle_vgpu(gvt->idle_vgpu); - intel_gvt_hypervisor_host_exit(&dev_priv->drm.pdev->dev); intel_gvt_cleanup_vgpu_type_groups(gvt); intel_gvt_clean_vgpu_types(gvt); @@ -352,13 +305,6 @@ int intel_gvt_init_device(struct drm_i915_private *dev_priv) struct intel_vgpu *vgpu; int ret; - /* - * Cannot initialize GVT device without intel_gvt_host gets - * initialized first. - */ - if (WARN_ON(!intel_gvt_host.initialized)) - return -EINVAL; - if (WARN_ON(dev_priv->gvt)) return -EEXIST; @@ -420,13 +366,6 @@ int intel_gvt_init_device(struct drm_i915_private *dev_priv) goto out_clean_types; } - ret = intel_gvt_hypervisor_host_init(&dev_priv->drm.pdev->dev, gvt, - &intel_gvt_ops); - if (ret) { - gvt_err("failed to register gvt-g host device: %d\n", ret); - goto out_clean_types; - } - vgpu = intel_gvt_create_idle_vgpu(gvt); if (IS_ERR(vgpu)) { ret = PTR_ERR(vgpu); @@ -441,6 +380,8 @@ int intel_gvt_init_device(struct drm_i915_private *dev_priv) gvt_dbg_core("gvt device initialization is done\n"); dev_priv->gvt = gvt; + intel_gvt_host.dev = &dev_priv->drm.pdev->dev; + intel_gvt_host.initialized = true; return 0; out_clean_types: @@ -467,6 +408,45 @@ out_clean_idr: return ret; } -#if IS_ENABLED(CONFIG_DRM_I915_GVT_KVMGT) -MODULE_SOFTDEP("pre: kvmgt"); -#endif +int +intel_gvt_register_hypervisor(struct intel_gvt_mpt *m) +{ + int ret; + void *gvt; + + if (!intel_gvt_host.initialized) + return -ENODEV; + + if (m->type != INTEL_GVT_HYPERVISOR_KVM && + m->type != INTEL_GVT_HYPERVISOR_XEN) + return -EINVAL; + + /* Get a reference for device model module */ + if (!try_module_get(THIS_MODULE)) + return -ENODEV; + + intel_gvt_host.mpt = m; + intel_gvt_host.hypervisor_type = m->type; + gvt = (void *)kdev_to_i915(intel_gvt_host.dev)->gvt; + + ret = intel_gvt_hypervisor_host_init(intel_gvt_host.dev, gvt, + &intel_gvt_ops); + if (ret < 0) { + gvt_err("Failed to init %s hypervisor module\n", + supported_hypervisors[intel_gvt_host.hypervisor_type]); + module_put(THIS_MODULE); + return -ENODEV; + } + gvt_dbg_core("Running with hypervisor %s in host mode\n", + supported_hypervisors[intel_gvt_host.hypervisor_type]); + return 0; +} +EXPORT_SYMBOL_GPL(intel_gvt_register_hypervisor); + +void +intel_gvt_unregister_hypervisor(void) +{ + intel_gvt_hypervisor_host_exit(intel_gvt_host.dev); + module_put(THIS_MODULE); +} +EXPORT_SYMBOL_GPL(intel_gvt_unregister_hypervisor); diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h index b4ab1dad0143..8a4cf995d755 100644 --- a/drivers/gpu/drm/i915/gvt/gvt.h +++ b/drivers/gpu/drm/i915/gvt/gvt.h @@ -52,12 +52,8 @@ #define GVT_MAX_VGPU 8 -enum { - INTEL_GVT_HYPERVISOR_XEN = 0, - INTEL_GVT_HYPERVISOR_KVM, -}; - struct intel_gvt_host { + struct device *dev; bool initialized; int hypervisor_type; struct intel_gvt_mpt *mpt; diff --git a/drivers/gpu/drm/i915/gvt/hypercall.h b/drivers/gpu/drm/i915/gvt/hypercall.h index e49a9247ed78..50798868ab15 100644 --- a/drivers/gpu/drm/i915/gvt/hypercall.h +++ b/drivers/gpu/drm/i915/gvt/hypercall.h @@ -33,11 +33,17 @@ #ifndef _GVT_HYPERCALL_H_ #define _GVT_HYPERCALL_H_ +enum hypervisor_type { + INTEL_GVT_HYPERVISOR_XEN = 0, + INTEL_GVT_HYPERVISOR_KVM, +}; + /* * Specific GVT-g MPT modules function collections. Currently GVT-g supports * both Xen and KVM by providing dedicated hypervisor-related MPT modules. */ struct intel_gvt_mpt { + enum hypervisor_type type; int (*host_init)(struct device *dev, void *gvt, const void *ops); void (*host_exit)(struct device *dev); int (*attach_vgpu)(void *vgpu, unsigned long *handle); @@ -67,6 +73,5 @@ struct intel_gvt_mpt { }; extern struct intel_gvt_mpt xengt_mpt; -extern struct intel_gvt_mpt kvmgt_mpt; #endif /* _GVT_HYPERCALL_H_ */ diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c index 1bbd04d30c42..a19e684e621a 100644 --- a/drivers/gpu/drm/i915/gvt/kvmgt.c +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c @@ -627,6 +627,12 @@ static int intel_vgpu_open(struct mdev_device *mdev) goto undo_iommu; } + /* Take a module reference as mdev core doesn't take + * a reference for vendor driver. + */ + if (!try_module_get(THIS_MODULE)) + goto undo_group; + ret = kvmgt_guest_init(mdev); if (ret) goto undo_group; @@ -679,6 +685,9 @@ static void __intel_vgpu_release(struct intel_vgpu *vgpu) &vgpu->vdev.group_notifier); WARN(ret, "vfio_unregister_notifier for group failed: %d\n", ret); + /* dereference module reference taken at open */ + module_put(THIS_MODULE); + info = (struct kvmgt_guest_info *)vgpu->handle; kvmgt_guest_exit(info); @@ -1849,7 +1858,8 @@ static bool kvmgt_is_valid_gfn(unsigned long handle, unsigned long gfn) return ret; } -struct intel_gvt_mpt kvmgt_mpt = { +static struct intel_gvt_mpt kvmgt_mpt = { + .type = INTEL_GVT_HYPERVISOR_KVM, .host_init = kvmgt_host_init, .host_exit = kvmgt_host_exit, .attach_vgpu = kvmgt_attach_vgpu, @@ -1868,15 +1878,17 @@ struct intel_gvt_mpt kvmgt_mpt = { .put_vfio_device = kvmgt_put_vfio_device, .is_valid_gfn = kvmgt_is_valid_gfn, }; -EXPORT_SYMBOL_GPL(kvmgt_mpt); static int __init kvmgt_init(void) { + if (intel_gvt_register_hypervisor(&kvmgt_mpt) < 0) + return -ENODEV; return 0; } static void __exit kvmgt_exit(void) { + intel_gvt_unregister_hypervisor(); } module_init(kvmgt_init); diff --git a/drivers/gpu/drm/i915/gvt/mpt.h b/drivers/gpu/drm/i915/gvt/mpt.h index c95ef77da62c..9b4225d44243 100644 --- a/drivers/gpu/drm/i915/gvt/mpt.h +++ b/drivers/gpu/drm/i915/gvt/mpt.h @@ -360,4 +360,7 @@ static inline bool intel_gvt_hypervisor_is_valid_gfn( return intel_gvt_host.mpt->is_valid_gfn(vgpu->handle, gfn); } +int intel_gvt_register_hypervisor(struct intel_gvt_mpt *); +void intel_gvt_unregister_hypervisor(void); + #endif /* _GVT_MPT_H_ */ diff --git a/drivers/gpu/drm/i915/intel_gvt.c b/drivers/gpu/drm/i915/intel_gvt.c index c22b3e18a0f5..d74e59e22c9d 100644 --- a/drivers/gpu/drm/i915/intel_gvt.c +++ b/drivers/gpu/drm/i915/intel_gvt.c @@ -105,15 +105,6 @@ int intel_gvt_init(struct drm_i915_private *dev_priv) return -EIO; } - /* - * We're not in host or fail to find a MPT module, disable GVT-g - */ - ret = intel_gvt_init_host(); - if (ret) { - DRM_DEBUG_DRIVER("Not in host or MPT modules not found\n"); - goto bail; - } - ret = intel_gvt_init_device(dev_priv); if (ret) { DRM_DEBUG_DRIVER("Fail to init GVT device\n");