6.1-stable review patch. If anyone has any objections, please let me know.
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From: Nirmoy Das nirmoy.das@intel.com
[ Upstream commit eaee1c08586395182e0004b3512a2f83570ea461 ]
Implement i915_gem_fb_mmap() to enable fb_ops.fb_mmap() callback for i915's framebuffer objects.
v2: add a comment why i915_gem_object_get() needed(Andi). v3: mmap also ttm objects.
Cc: Matthew Auld matthew.auld@intel.com Cc: Andi Shyti andi.shyti@linux.intel.com Cc: Ville Syrjälä ville.syrjala@linux.intel.com Cc: Jani Nikula jani.nikula@intel.com Cc: Imre Deak imre.deak@intel.com Signed-off-by: Nirmoy Das nirmoy.das@intel.com Reviewed-by: Andi Shyti andi.shyti@linux.intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20230404143100.10452-3-nirmoy.... Stable-dep-of: 1ac5167b3a90 ("drm/i915/gem: Adjust vma offset for framebuffer mmap offset") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/i915/gem/i915_gem_mman.c | 137 +++++++++++++++-------- drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 +- 2 files changed, 93 insertions(+), 46 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c index 1fd704d9cf9a9..180b66f6193cb 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c @@ -969,53 +969,15 @@ static struct file *mmap_singleton(struct drm_i915_private *i915) return file; }
-/* - * This overcomes the limitation in drm_gem_mmap's assignment of a - * drm_gem_object as the vma->vm_private_data. Since we need to - * be able to resolve multiple mmap offsets which could be tied - * to a single gem object. - */ -int i915_gem_mmap(struct file *filp, struct vm_area_struct *vma) +static int +i915_gem_object_mmap(struct drm_i915_gem_object *obj, + struct i915_mmap_offset *mmo, + struct vm_area_struct *vma) { - struct drm_vma_offset_node *node; - struct drm_file *priv = filp->private_data; - struct drm_device *dev = priv->minor->dev; - struct drm_i915_gem_object *obj = NULL; - struct i915_mmap_offset *mmo = NULL; + struct drm_i915_private *i915 = to_i915(obj->base.dev); + struct drm_device *dev = &i915->drm; struct file *anon;
- if (drm_dev_is_unplugged(dev)) - return -ENODEV; - - rcu_read_lock(); - drm_vma_offset_lock_lookup(dev->vma_offset_manager); - node = drm_vma_offset_exact_lookup_locked(dev->vma_offset_manager, - vma->vm_pgoff, - vma_pages(vma)); - if (node && drm_vma_node_is_allowed(node, priv)) { - /* - * Skip 0-refcnted objects as it is in the process of being - * destroyed and will be invalid when the vma manager lock - * is released. - */ - if (!node->driver_private) { - mmo = container_of(node, struct i915_mmap_offset, vma_node); - obj = i915_gem_object_get_rcu(mmo->obj); - - GEM_BUG_ON(obj && obj->ops->mmap_ops); - } else { - obj = i915_gem_object_get_rcu - (container_of(node, struct drm_i915_gem_object, - base.vma_node)); - - GEM_BUG_ON(obj && !obj->ops->mmap_ops); - } - } - drm_vma_offset_unlock_lookup(dev->vma_offset_manager); - rcu_read_unlock(); - if (!obj) - return node ? -EACCES : -EINVAL; - if (i915_gem_object_is_readonly(obj)) { if (vma->vm_flags & VM_WRITE) { i915_gem_object_put(obj); @@ -1047,7 +1009,7 @@ int i915_gem_mmap(struct file *filp, struct vm_area_struct *vma) if (obj->ops->mmap_ops) { vma->vm_page_prot = pgprot_decrypted(vm_get_page_prot(vma->vm_flags)); vma->vm_ops = obj->ops->mmap_ops; - vma->vm_private_data = node->driver_private; + vma->vm_private_data = obj->base.vma_node.driver_private; return 0; }
@@ -1085,6 +1047,91 @@ int i915_gem_mmap(struct file *filp, struct vm_area_struct *vma) return 0; }
+/* + * This overcomes the limitation in drm_gem_mmap's assignment of a + * drm_gem_object as the vma->vm_private_data. Since we need to + * be able to resolve multiple mmap offsets which could be tied + * to a single gem object. + */ +int i915_gem_mmap(struct file *filp, struct vm_area_struct *vma) +{ + struct drm_vma_offset_node *node; + struct drm_file *priv = filp->private_data; + struct drm_device *dev = priv->minor->dev; + struct drm_i915_gem_object *obj = NULL; + struct i915_mmap_offset *mmo = NULL; + + if (drm_dev_is_unplugged(dev)) + return -ENODEV; + + rcu_read_lock(); + drm_vma_offset_lock_lookup(dev->vma_offset_manager); + node = drm_vma_offset_exact_lookup_locked(dev->vma_offset_manager, + vma->vm_pgoff, + vma_pages(vma)); + if (node && drm_vma_node_is_allowed(node, priv)) { + /* + * Skip 0-refcnted objects as it is in the process of being + * destroyed and will be invalid when the vma manager lock + * is released. + */ + if (!node->driver_private) { + mmo = container_of(node, struct i915_mmap_offset, vma_node); + obj = i915_gem_object_get_rcu(mmo->obj); + + GEM_BUG_ON(obj && obj->ops->mmap_ops); + } else { + obj = i915_gem_object_get_rcu + (container_of(node, struct drm_i915_gem_object, + base.vma_node)); + + GEM_BUG_ON(obj && !obj->ops->mmap_ops); + } + } + drm_vma_offset_unlock_lookup(dev->vma_offset_manager); + rcu_read_unlock(); + if (!obj) + return node ? -EACCES : -EINVAL; + + return i915_gem_object_mmap(obj, mmo, vma); +} + +int i915_gem_fb_mmap(struct drm_i915_gem_object *obj, struct vm_area_struct *vma) +{ + struct drm_i915_private *i915 = to_i915(obj->base.dev); + struct drm_device *dev = &i915->drm; + struct i915_mmap_offset *mmo = NULL; + enum i915_mmap_type mmap_type; + struct i915_ggtt *ggtt = to_gt(i915)->ggtt; + + if (drm_dev_is_unplugged(dev)) + return -ENODEV; + + /* handle ttm object */ + if (obj->ops->mmap_ops) { + /* + * ttm fault handler, ttm_bo_vm_fault_reserved() uses fake offset + * to calculate page offset so set that up. + */ + vma->vm_pgoff += drm_vma_node_start(&obj->base.vma_node); + } else { + /* handle stolen and smem objects */ + mmap_type = i915_ggtt_has_aperture(ggtt) ? I915_MMAP_TYPE_GTT : I915_MMAP_TYPE_WC; + mmo = mmap_offset_attach(obj, mmap_type, NULL); + if (!mmo) + return -ENODEV; + } + + /* + * When we install vm_ops for mmap we are too late for + * the vm_ops->open() which increases the ref_count of + * this obj and then it gets decreased by the vm_ops->close(). + * To balance this increase the obj ref_count here. + */ + obj = i915_gem_object_get(obj); + return i915_gem_object_mmap(obj, mmo, vma); +} + #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST) #include "selftests/i915_gem_mman.c" #endif diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h index 1fa91b3033b35..196417fd0f5c4 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h +++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h @@ -29,5 +29,5 @@ void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
void i915_gem_object_runtime_pm_release_mmap_offset(struct drm_i915_gem_object *obj); void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj); - +int i915_gem_fb_mmap(struct drm_i915_gem_object *obj, struct vm_area_struct *vma); #endif