diff mbox series

[1/2] drm/i915/gvt: Move mdev attribute groups into kvmgt module

Message ID 20210426094143.4031527-1-zhenyuw@linux.intel.com (mailing list archive)
State New, archived
Headers show
Series [1/2] drm/i915/gvt: Move mdev attribute groups into kvmgt module | expand

Commit Message

Zhenyu Wang April 26, 2021, 9:41 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 April 27, 2021, 2:45 a.m. UTC | #1 
On 2021.04.26 10:39:24 -0300, Jason Gunthorpe wrote:
> On Mon, Apr 26, 2021 at 05:41:42PM +0800, Zhenyu Wang wrote:
> > @@ -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;
> 
> This patch is an improvement, but this fictional dynamic behavior is
> still wrong. The supported_type_groups directly flows from the
> vgpu_types array in vgpu.c and it should not be split up like this
> 
> The code copies the rodata vgpu_types into dynamic memory gvt->types
> then copies that dynamic memory into a dynamic gvt_vgpu_type_groups,
> which makes very little sense at all.

vgpu_types is static for we want fixed vgpu mdev type, but actual supported
types depend on HW resources e.g aperture mem, fence, etc, that's dynamic for
gvt->types, so gvt_vgpu_type_groups is dynamic from gvt->types.

> 
> vgpu_types should be moved to kvmgt and everything should be static,
> like every other mdev driver. Copy the 'type' information from the
> gpu_types static when the mdev is created.
> 

I don't think that's necessary, as it's not static for gvt at all.
The logic to handle type resource change can still be in vgpu.c
Zhenyu Wang April 28, 2021, 5:32 a.m. UTC | #2 
On 2021.04.27 09:12:35 -0300, Jason Gunthorpe wrote:
> On Tue, Apr 27, 2021 at 10:45:06AM +0800, Zhenyu Wang wrote:
> > On 2021.04.26 10:39:24 -0300, Jason Gunthorpe wrote:
> > > On Mon, Apr 26, 2021 at 05:41:42PM +0800, Zhenyu Wang wrote:
> > > > @@ -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;
> > > 
> > > This patch is an improvement, but this fictional dynamic behavior is
> > > still wrong. The supported_type_groups directly flows from the
> > > vgpu_types array in vgpu.c and it should not be split up like this
> > > 
> > > The code copies the rodata vgpu_types into dynamic memory gvt->types
> > > then copies that dynamic memory into a dynamic gvt_vgpu_type_groups,
> > > which makes very little sense at all.
> > 
> > vgpu_types is static for we want fixed vgpu mdev type, but actual supported
> > types depend on HW resources e.g aperture mem, fence, etc, that's dynamic for
> > gvt->types, so gvt_vgpu_type_groups is dynamic from gvt->types.
> 
> Well, that's worse then, intel_vgpu_ops.supported_type_groups is a
> static global, it cannot depend on HW variable calculations.
> 

sorry, maybe I didn't describe this properly, gvt_vgpu_type_groups is
static global, but the actual supported types is determined from
gvt->types and initialized before mdev device register.
Zhenyu Wang April 29, 2021, 2:40 a.m. UTC | #3 
On 2021.04.28 14:21:41 -0300, Jason Gunthorpe wrote:
> On Wed, Apr 28, 2021 at 01:32:43PM +0800, Zhenyu Wang wrote:
> > On 2021.04.27 09:12:35 -0300, Jason Gunthorpe wrote:
> > > On Tue, Apr 27, 2021 at 10:45:06AM +0800, Zhenyu Wang wrote:
> > > > On 2021.04.26 10:39:24 -0300, Jason Gunthorpe wrote:
> > > > > On Mon, Apr 26, 2021 at 05:41:42PM +0800, Zhenyu Wang wrote:
> > > > > > @@ -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;
> > > > > 
> > > > > This patch is an improvement, but this fictional dynamic behavior is
> > > > > still wrong. The supported_type_groups directly flows from the
> > > > > vgpu_types array in vgpu.c and it should not be split up like this
> > > > > 
> > > > > The code copies the rodata vgpu_types into dynamic memory gvt->types
> > > > > then copies that dynamic memory into a dynamic gvt_vgpu_type_groups,
> > > > > which makes very little sense at all.
> > > > 
> > > > vgpu_types is static for we want fixed vgpu mdev type, but actual supported
> > > > types depend on HW resources e.g aperture mem, fence, etc, that's dynamic for
> > > > gvt->types, so gvt_vgpu_type_groups is dynamic from gvt->types.
> > > 
> > > Well, that's worse then, intel_vgpu_ops.supported_type_groups is a
> > > static global, it cannot depend on HW variable calculations.
> > 
> > sorry, maybe I didn't describe this properly, gvt_vgpu_type_groups is
> > static global, but the actual supported types is determined from
> > gvt->types and initialized before mdev device register.
> 
> No, I got it, I saw the code too.
> 
> Think about what happens if there are two GPUs in the system, you get
> two gvt's and with different properties and you are trying to squeeze
> that into a single static global - it doesn't work. 
> 

Well, that's not what this change trys to resolve and on gvt supported platform
that's not an available hardware configuration for IGD. So I think this is fine.
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);
 }
 
 /**