diff mbox series

[1/3] drm/i915/gvt: Move mdev attribute groups into kvmgt module

Message ID 20210511083332.1740601-2-zhenyuw@linux.intel.com (mailing list archive)
State New, archived
Headers show
Series Fix I915_GVT dependency | expand

Commit Message

Zhenyu Wang May 11, 2021, 8:33 a.m. UTC 
As kvmgt module contains all handling for VFIO/mdev, leaving mdev attribute
groups in gvt module caused dependency issue. Although it was there for possible
other hypervisor usage, that turns out never to be true. So this moves all mdev
handling into kvmgt module completely to resolve dependency issue.

Cc: Arnd Bergmann <arnd@kernel.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
---
 drivers/gpu/drm/i915/gvt/gvt.c       | 124 +------------------------
 drivers/gpu/drm/i915/gvt/gvt.h       |   3 -
 drivers/gpu/drm/i915/gvt/hypercall.h |   2 +-
 drivers/gpu/drm/i915/gvt/kvmgt.c     | 129 +++++++++++++++++++++++++--
 drivers/gpu/drm/i915/gvt/mpt.h       |   4 +-
 5 files changed, 126 insertions(+), 136 deletions(-)

Comments

Zhenyu Wang May 12, 2021, 2:31 a.m. UTC | #1 
On 2021.05.11 12:54:46 -0300, Jason Gunthorpe wrote:
> On Tue, May 11, 2021 at 04:33:30PM +0800, Zhenyu Wang wrote:
> > As kvmgt module contains all handling for VFIO/mdev, leaving mdev attribute
> > groups in gvt module caused dependency issue. Although it was there for possible
> > other hypervisor usage, that turns out never to be true. So this moves all mdev
> > handling into kvmgt module completely to resolve dependency issue.
> > 
> > Cc: Arnd Bergmann <arnd@kernel.org>
> > Cc: Jason Gunthorpe <jgg@ziepe.ca>
> > Cc: Alex Williamson <alex.williamson@redhat.com>
> > Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
> > ---
> >  drivers/gpu/drm/i915/gvt/gvt.c       | 124 +------------------------
> >  drivers/gpu/drm/i915/gvt/gvt.h       |   3 -
> >  drivers/gpu/drm/i915/gvt/hypercall.h |   2 +-
> >  drivers/gpu/drm/i915/gvt/kvmgt.c     | 129 +++++++++++++++++++++++++--
> >  drivers/gpu/drm/i915/gvt/mpt.h       |   4 +-
> >  5 files changed, 126 insertions(+), 136 deletions(-)
> 
> There is no reason to make this into three patches, just make the one
> line change to kconfig here.
> 
> > +static struct intel_vgpu_type *
> > +intel_gvt_find_vgpu_type(struct intel_gvt *gvt, unsigned int type_group_id)
> > +{
> > +	if (WARN_ON(type_group_id >= gvt->num_types))
> > +		return NULL;
> > +	return &gvt->types[type_group_id];
> > +}
> 
> The WARN_ON can't happen, all this error handling is code should be
> deleted, just use the simple
> 
> struct intel_gvt *gvt = kdev_to_i915(mtype_get_parent_dev(mtype))->gvt;
> struct intel_vgpu_type *type = &gvt->types[mtype_get_type_group_id(mtype)]
> 
> sequence like the other mdev drivers
> 
> > +static ssize_t available_instances_show(struct mdev_type *mtype,
> > +					struct mdev_type_attribute *attr,
> > +					char *buf)
> > +{
> > +	struct intel_vgpu_type *type;
> > +	unsigned int num = 0;
> > +	void *gvt = kdev_to_i915(mtype_get_parent_dev(mtype))->gvt;
> 
> Use proper types not 'void *'
> > +
> > +static int intel_gvt_init_vgpu_type_groups(struct intel_gvt *gvt)
> > +{
> > +	int i, j;
> > +	struct intel_vgpu_type *type;
> > +	struct attribute_group *group;
> > +
> > +	for (i = 0; i < gvt->num_types; i++) {
> > +		type = &gvt->types[i];
> > +
> > +		group = kzalloc(sizeof(struct attribute_group), GFP_KERNEL);
> > +		if (WARN_ON(!group))
> > +			goto unwind;
> 
> WARN_ON at allocation failure is not good

Thanks for the comments! I left those during code move, will clean them up.

> 
> This need to go into the vfio tree in some way, either directly
> through it, via rc or otherwise
> 

As this is only for i915/gvt, once drm/i915 backmerge with linus master,
it should still go through normal i915/gvt merge path.

Thanks
Zhenyu Wang May 13, 2021, 4:56 a.m. UTC | #2 
On 2021.05.12 09:47:39 -0300, Jason Gunthorpe wrote:
> On Wed, May 12, 2021 at 10:31:41AM +0800, Zhenyu Wang wrote:
> 
> > > This need to go into the vfio tree in some way, either directly
> > > through it, via rc or otherwise
> > 
> > As this is only for i915/gvt, once drm/i915 backmerge with linus master,
> > it should still go through normal i915/gvt merge path.
> 
> Don't do this, you will create conflicts with ongoing vfio work.
> 

Sure, there always could be conflict, which means you need to rebase onto
this cleanup. Would that a problem? I'd want to fix current workaround
in 5.13-rc.  Merging i915/gvt only change through vfio doesn't make sense
to me, I will handle that instead of Alex.

Thanks
Zhenyu Wang May 14, 2021, 7:08 a.m. UTC | #3 
On 2021.05.13 09:02:49 -0300, Jason Gunthorpe wrote:
> On Thu, May 13, 2021 at 12:56:47PM +0800, Zhenyu Wang wrote:
> > On 2021.05.12 09:47:39 -0300, Jason Gunthorpe wrote:
> > > On Wed, May 12, 2021 at 10:31:41AM +0800, Zhenyu Wang wrote:
> > > 
> > > > > This need to go into the vfio tree in some way, either directly
> > > > > through it, via rc or otherwise
> > > > 
> > > > As this is only for i915/gvt, once drm/i915 backmerge with linus master,
> > > > it should still go through normal i915/gvt merge path.
> > > 
> > > Don't do this, you will create conflicts with ongoing vfio work.
> > > 
> > 
> > Sure, there always could be conflict, which means you need to rebase onto
> > this cleanup. Would that a problem? 
> 
> Yes.
> 
> > I'd want to fix current workaround in 5.13-rc.
> 
> This doesn't seem like a rc candiate to me, but going to -rc is also
> fine.
> 
> > Merging i915/gvt only change through vfio doesn't make sense to me,
> 
> You need to do it to avoid major conflicts for stuff that will go into
> the vfio tree this cycle.

Looks apply to vfio/for-linus is fine, and vfio/next missed gvt change to
apply...but not conflict with any new stuff. Alex, pls let me know if you
have any concern of this.

> 
> VFIO drivers should not be outside drivers/vfio/ in the first place,
> and this shows why.
> 

Well, I can't agree, otherwise that'll be dependency nightmare for device
driver writer. ;)
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/gvt/gvt.c b/drivers/gpu/drm/i915/gvt/gvt.c
index e7c2babcee8b..cbac409f6c8a 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.c
+++ b/drivers/gpu/drm/i915/gvt/gvt.c
@@ -46,118 +46,6 @@  static const char * const supported_hypervisors[] = {
 	[INTEL_GVT_HYPERVISOR_KVM] = "KVM",
 };
 
-static struct intel_vgpu_type *
-intel_gvt_find_vgpu_type(struct intel_gvt *gvt, unsigned int type_group_id)
-{
-	if (WARN_ON(type_group_id >= gvt->num_types))
-		return NULL;
-	return &gvt->types[type_group_id];
-}
-
-static ssize_t available_instances_show(struct mdev_type *mtype,
-					struct mdev_type_attribute *attr,
-					char *buf)
-{
-	struct intel_vgpu_type *type;
-	unsigned int num = 0;
-	void *gvt = kdev_to_i915(mtype_get_parent_dev(mtype))->gvt;
-
-	type = intel_gvt_find_vgpu_type(gvt, mtype_get_type_group_id(mtype));
-	if (!type)
-		num = 0;
-	else
-		num = type->avail_instance;
-
-	return sprintf(buf, "%u\n", num);
-}
-
-static ssize_t device_api_show(struct mdev_type *mtype,
-			       struct mdev_type_attribute *attr, char *buf)
-{
-	return sprintf(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
-}
-
-static ssize_t description_show(struct mdev_type *mtype,
-				struct mdev_type_attribute *attr, char *buf)
-{
-	struct intel_vgpu_type *type;
-	void *gvt = kdev_to_i915(mtype_get_parent_dev(mtype))->gvt;
-
-	type = intel_gvt_find_vgpu_type(gvt, mtype_get_type_group_id(mtype));
-	if (!type)
-		return 0;
-
-	return sprintf(buf, "low_gm_size: %dMB\nhigh_gm_size: %dMB\n"
-		       "fence: %d\nresolution: %s\n"
-		       "weight: %d\n",
-		       BYTES_TO_MB(type->low_gm_size),
-		       BYTES_TO_MB(type->high_gm_size),
-		       type->fence, vgpu_edid_str(type->resolution),
-		       type->weight);
-}
-
-static MDEV_TYPE_ATTR_RO(available_instances);
-static MDEV_TYPE_ATTR_RO(device_api);
-static MDEV_TYPE_ATTR_RO(description);
-
-static struct attribute *gvt_type_attrs[] = {
-	&mdev_type_attr_available_instances.attr,
-	&mdev_type_attr_device_api.attr,
-	&mdev_type_attr_description.attr,
-	NULL,
-};
-
-static struct attribute_group *gvt_vgpu_type_groups[] = {
-	[0 ... NR_MAX_INTEL_VGPU_TYPES - 1] = NULL,
-};
-
-static bool intel_get_gvt_attrs(struct attribute_group ***intel_vgpu_type_groups)
-{
-	*intel_vgpu_type_groups = gvt_vgpu_type_groups;
-	return true;
-}
-
-static int intel_gvt_init_vgpu_type_groups(struct intel_gvt *gvt)
-{
-	int i, j;
-	struct intel_vgpu_type *type;
-	struct attribute_group *group;
-
-	for (i = 0; i < gvt->num_types; i++) {
-		type = &gvt->types[i];
-
-		group = kzalloc(sizeof(struct attribute_group), GFP_KERNEL);
-		if (WARN_ON(!group))
-			goto unwind;
-
-		group->name = type->name;
-		group->attrs = gvt_type_attrs;
-		gvt_vgpu_type_groups[i] = group;
-	}
-
-	return 0;
-
-unwind:
-	for (j = 0; j < i; j++) {
-		group = gvt_vgpu_type_groups[j];
-		kfree(group);
-	}
-
-	return -ENOMEM;
-}
-
-static void intel_gvt_cleanup_vgpu_type_groups(struct intel_gvt *gvt)
-{
-	int i;
-	struct attribute_group *group;
-
-	for (i = 0; i < gvt->num_types; i++) {
-		group = gvt_vgpu_type_groups[i];
-		gvt_vgpu_type_groups[i] = NULL;
-		kfree(group);
-	}
-}
-
 static const struct intel_gvt_ops intel_gvt_ops = {
 	.emulate_cfg_read = intel_vgpu_emulate_cfg_read,
 	.emulate_cfg_write = intel_vgpu_emulate_cfg_write,
@@ -169,8 +57,6 @@  static const struct intel_gvt_ops intel_gvt_ops = {
 	.vgpu_reset = intel_gvt_reset_vgpu,
 	.vgpu_activate = intel_gvt_activate_vgpu,
 	.vgpu_deactivate = intel_gvt_deactivate_vgpu,
-	.gvt_find_vgpu_type = intel_gvt_find_vgpu_type,
-	.get_gvt_attrs = intel_get_gvt_attrs,
 	.vgpu_query_plane = intel_vgpu_query_plane,
 	.vgpu_get_dmabuf = intel_vgpu_get_dmabuf,
 	.write_protect_handler = intel_vgpu_page_track_handler,
@@ -274,7 +160,6 @@  void intel_gvt_clean_device(struct drm_i915_private *i915)
 		return;
 
 	intel_gvt_destroy_idle_vgpu(gvt->idle_vgpu);
-	intel_gvt_cleanup_vgpu_type_groups(gvt);
 	intel_gvt_clean_vgpu_types(gvt);
 
 	intel_gvt_debugfs_clean(gvt);
@@ -363,12 +248,6 @@  int intel_gvt_init_device(struct drm_i915_private *i915)
 	if (ret)
 		goto out_clean_thread;
 
-	ret = intel_gvt_init_vgpu_type_groups(gvt);
-	if (ret) {
-		gvt_err("failed to init vgpu type groups: %d\n", ret);
-		goto out_clean_types;
-	}
-
 	vgpu = intel_gvt_create_idle_vgpu(gvt);
 	if (IS_ERR(vgpu)) {
 		ret = PTR_ERR(vgpu);
@@ -454,7 +333,8 @@  EXPORT_SYMBOL_GPL(intel_gvt_register_hypervisor);
 void
 intel_gvt_unregister_hypervisor(void)
 {
-	intel_gvt_hypervisor_host_exit(intel_gvt_host.dev);
+	void *gvt = (void *)kdev_to_i915(intel_gvt_host.dev)->gvt;
+	intel_gvt_hypervisor_host_exit(intel_gvt_host.dev, gvt);
 	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 88ab360fcb31..0c0615602343 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.h
+++ b/drivers/gpu/drm/i915/gvt/gvt.h
@@ -574,9 +574,6 @@  struct intel_gvt_ops {
 	void (*vgpu_reset)(struct intel_vgpu *);
 	void (*vgpu_activate)(struct intel_vgpu *);
 	void (*vgpu_deactivate)(struct intel_vgpu *);
-	struct intel_vgpu_type *(*gvt_find_vgpu_type)(
-		struct intel_gvt *gvt, unsigned int type_group_id);
-	bool (*get_gvt_attrs)(struct attribute_group ***intel_vgpu_type_groups);
 	int (*vgpu_query_plane)(struct intel_vgpu *vgpu, void *);
 	int (*vgpu_get_dmabuf)(struct intel_vgpu *vgpu, unsigned int);
 	int (*write_protect_handler)(struct intel_vgpu *, u64, void *,
diff --git a/drivers/gpu/drm/i915/gvt/hypercall.h b/drivers/gpu/drm/i915/gvt/hypercall.h
index b79da5124f83..f33e3cbd0439 100644
--- a/drivers/gpu/drm/i915/gvt/hypercall.h
+++ b/drivers/gpu/drm/i915/gvt/hypercall.h
@@ -49,7 +49,7 @@  enum hypervisor_type {
 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);
+	void (*host_exit)(struct device *dev, void *gvt);
 	int (*attach_vgpu)(void *vgpu, unsigned long *handle);
 	void (*detach_vgpu)(void *vgpu);
 	int (*inject_msi)(unsigned long handle, u32 addr, u16 data);
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index 65ff43cfc0f7..fe0ddd687d44 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -144,6 +144,112 @@  static inline bool handle_valid(unsigned long handle)
 	return !!(handle & ~0xff);
 }
 
+static struct intel_vgpu_type *
+intel_gvt_find_vgpu_type(struct intel_gvt *gvt, unsigned int type_group_id)
+{
+	if (WARN_ON(type_group_id >= gvt->num_types))
+		return NULL;
+	return &gvt->types[type_group_id];
+}
+
+static ssize_t available_instances_show(struct mdev_type *mtype,
+					struct mdev_type_attribute *attr,
+					char *buf)
+{
+	struct intel_vgpu_type *type;
+	unsigned int num = 0;
+	void *gvt = kdev_to_i915(mtype_get_parent_dev(mtype))->gvt;
+
+	type = intel_gvt_find_vgpu_type(gvt, mtype_get_type_group_id(mtype));
+	if (!type)
+		num = 0;
+	else
+		num = type->avail_instance;
+
+	return sprintf(buf, "%u\n", num);
+}
+
+static ssize_t device_api_show(struct mdev_type *mtype,
+			       struct mdev_type_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
+}
+
+static ssize_t description_show(struct mdev_type *mtype,
+				struct mdev_type_attribute *attr, char *buf)
+{
+	struct intel_vgpu_type *type;
+	void *gvt = kdev_to_i915(mtype_get_parent_dev(mtype))->gvt;
+
+	type = intel_gvt_find_vgpu_type(gvt, mtype_get_type_group_id(mtype));
+	if (!type)
+		return 0;
+
+	return sprintf(buf, "low_gm_size: %dMB\nhigh_gm_size: %dMB\n"
+		       "fence: %d\nresolution: %s\n"
+		       "weight: %d\n",
+		       BYTES_TO_MB(type->low_gm_size),
+		       BYTES_TO_MB(type->high_gm_size),
+		       type->fence, vgpu_edid_str(type->resolution),
+		       type->weight);
+}
+
+static MDEV_TYPE_ATTR_RO(available_instances);
+static MDEV_TYPE_ATTR_RO(device_api);
+static MDEV_TYPE_ATTR_RO(description);
+
+static struct attribute *gvt_type_attrs[] = {
+	&mdev_type_attr_available_instances.attr,
+	&mdev_type_attr_device_api.attr,
+	&mdev_type_attr_description.attr,
+	NULL,
+};
+
+static struct attribute_group *gvt_vgpu_type_groups[] = {
+	[0 ... NR_MAX_INTEL_VGPU_TYPES - 1] = NULL,
+};
+
+static int intel_gvt_init_vgpu_type_groups(struct intel_gvt *gvt)
+{
+	int i, j;
+	struct intel_vgpu_type *type;
+	struct attribute_group *group;
+
+	for (i = 0; i < gvt->num_types; i++) {
+		type = &gvt->types[i];
+
+		group = kzalloc(sizeof(struct attribute_group), GFP_KERNEL);
+		if (WARN_ON(!group))
+			goto unwind;
+
+		group->name = type->name;
+		group->attrs = gvt_type_attrs;
+		gvt_vgpu_type_groups[i] = group;
+	}
+
+	return 0;
+
+unwind:
+	for (j = 0; j < i; j++) {
+		group = gvt_vgpu_type_groups[j];
+		kfree(group);
+	}
+
+	return -ENOMEM;
+}
+
+static void intel_gvt_cleanup_vgpu_type_groups(struct intel_gvt *gvt)
+{
+	int i;
+	struct attribute_group *group;
+
+	for (i = 0; i < gvt->num_types; i++) {
+		group = gvt_vgpu_type_groups[i];
+		gvt_vgpu_type_groups[i] = NULL;
+		kfree(group);
+	}
+}
+
 static int kvmgt_guest_init(struct mdev_device *mdev);
 static void intel_vgpu_release_work(struct work_struct *work);
 static bool kvmgt_guest_exit(struct kvmgt_guest_info *info);
@@ -700,8 +806,8 @@  static int intel_vgpu_create(struct mdev_device *mdev)
 	pdev = mdev_parent_dev(mdev);
 	gvt = kdev_to_i915(pdev)->gvt;
 
-	type = intel_gvt_ops->gvt_find_vgpu_type(gvt,
-						 mdev_get_type_group_id(mdev));
+	type = intel_gvt_find_vgpu_type(gvt,
+					mdev_get_type_group_id(mdev));
 	if (!type) {
 		ret = -EINVAL;
 		goto out;
@@ -1667,19 +1773,26 @@  static struct mdev_parent_ops intel_vgpu_ops = {
 
 static int kvmgt_host_init(struct device *dev, void *gvt, const void *ops)
 {
-	struct attribute_group **kvm_vgpu_type_groups;
+	int ret;
+
+	ret = intel_gvt_init_vgpu_type_groups((struct intel_gvt *)gvt);
+	if (ret)
+		return ret;
 
 	intel_gvt_ops = ops;
-	if (!intel_gvt_ops->get_gvt_attrs(&kvm_vgpu_type_groups))
-		return -EFAULT;
-	intel_vgpu_ops.supported_type_groups = kvm_vgpu_type_groups;
+	intel_vgpu_ops.supported_type_groups = gvt_vgpu_type_groups;
 
-	return mdev_register_device(dev, &intel_vgpu_ops);
+	ret = mdev_register_device(dev, &intel_vgpu_ops);
+	if (ret)
+		intel_gvt_cleanup_vgpu_type_groups((struct intel_gvt *)gvt);
+
+	return ret;
 }
 
-static void kvmgt_host_exit(struct device *dev)
+static void kvmgt_host_exit(struct device *dev, void *gvt)
 {
 	mdev_unregister_device(dev);
+	intel_gvt_cleanup_vgpu_type_groups((struct intel_gvt *)gvt);
 }
 
 static int kvmgt_page_track_add(unsigned long handle, u64 gfn)
diff --git a/drivers/gpu/drm/i915/gvt/mpt.h b/drivers/gpu/drm/i915/gvt/mpt.h
index 550a456e936f..e6c5a792a49a 100644
--- a/drivers/gpu/drm/i915/gvt/mpt.h
+++ b/drivers/gpu/drm/i915/gvt/mpt.h
@@ -63,13 +63,13 @@  static inline int intel_gvt_hypervisor_host_init(struct device *dev,
 /**
  * intel_gvt_hypervisor_host_exit - exit GVT-g host side
  */
-static inline void intel_gvt_hypervisor_host_exit(struct device *dev)
+static inline void intel_gvt_hypervisor_host_exit(struct device *dev, void *gvt)
 {
 	/* optional to provide */
 	if (!intel_gvt_host.mpt->host_exit)
 		return;
 
-	intel_gvt_host.mpt->host_exit(dev);
+	intel_gvt_host.mpt->host_exit(dev, gvt);
 }
 
 /**