drm/i915: Prepare for non-object vma

In order to allow ourselves to use VMA to wrap other entities other than
GEM objects, we need to allow for the vma->obj backpointer to be NULL.
In most cases, we know we are operating on a GEM object and its vma, but
we need the core code (such as i915_vma_pin/insert/bind/unbind) to work
regardless of the innards.

The remaining eyesore here is vma->obj->cache_level and related (but
less of an issue) vma->obj->gt_ro. With a bit of care we should mirror
those on the vma itself.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180607154047.9171-1-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 2b4a40a32b765ab9b44ec1e06c6a1bb272377bc1..7c45a516aa6b2166e4d436fb8a1707a267a00590 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -3588,8 +3588,11 @@ void i915_gem_restore_gtt_mappings(struct drm_i915_private *dev_priv)
                if (!i915_vma_unbind(vma))
                        continue;
 
-               WARN_ON(i915_vma_bind(vma, obj->cache_level, PIN_UPDATE));
-               WARN_ON(i915_gem_object_set_to_gtt_domain(obj, false));
+               WARN_ON(i915_vma_bind(vma,
+                                     obj ? obj->cache_level : 0,
+                                     PIN_UPDATE));
+               if (obj)
+                       WARN_ON(i915_gem_object_set_to_gtt_domain(obj, false));
        }
 
        ggtt->vm.closed = false;

diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index 758234d20f4ea9b464bef01321a2d64a7253f538..df524c9cad40826626e8dfc30fae17d2f59b799c 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -1050,6 +1050,9 @@ static u32 capture_error_bo(struct drm_i915_error_buffer *err,
        int i = 0;
 
        list_for_each_entry(vma, head, vm_link) {
+               if (!vma->obj)
+                       continue;
+
                if (pinned_only && !i915_vma_is_pinned(vma))
                        continue;
 

diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
index 912f16ffe7eea4b62f1f562fd16938d1c69fb14f..b71265066cd16a2f55339963517c4f428682f48d 100644 (file)
--- a/drivers/gpu/drm/i915/i915_vma.c
+++ b/drivers/gpu/drm/i915/i915_vma.c
@@ -345,7 +345,7 @@ void i915_vma_flush_writes(struct i915_vma *vma)
 
 void i915_vma_unpin_iomap(struct i915_vma *vma)
 {
-       lockdep_assert_held(&vma->obj->base.dev->struct_mutex);
+       lockdep_assert_held(&vma->vm->i915->drm.struct_mutex);
 
        GEM_BUG_ON(vma->iomap == NULL);
 
@@ -365,6 +365,7 @@ void i915_vma_unpin_and_release(struct i915_vma **p_vma)
                return;
 
        obj = vma->obj;
+       GEM_BUG_ON(!obj);
 
        i915_vma_unpin(vma);
        i915_vma_close(vma);
@@ -489,7 +490,7 @@ static int
 i915_vma_insert(struct i915_vma *vma, u64 size, u64 alignment, u64 flags)
 {
        struct drm_i915_private *dev_priv = vma->vm->i915;
-       struct drm_i915_gem_object *obj = vma->obj;
+       unsigned int cache_level;
        u64 start, end;
        int ret;
 
@@ -524,16 +525,21 @@ i915_vma_insert(struct i915_vma *vma, u64 size, u64 alignment, u64 flags)
         * attempt to find space.
         */
        if (size > end) {
-               DRM_DEBUG("Attempting to bind an object larger than the aperture: request=%llu [object=%zd] > %s aperture=%llu\n",
-                         size, obj->base.size,
-                         flags & PIN_MAPPABLE ? "mappable" : "total",
+               DRM_DEBUG("Attempting to bind an object larger than the aperture: request=%llu > %s aperture=%llu\n",
+                         size, flags & PIN_MAPPABLE ? "mappable" : "total",
                          end);
                return -ENOSPC;
        }
 
-       ret = i915_gem_object_pin_pages(obj);
-       if (ret)
-               return ret;
+       if (vma->obj) {
+               ret = i915_gem_object_pin_pages(vma->obj);
+               if (ret)
+                       return ret;
+
+               cache_level = vma->obj->cache_level;
+       } else {
+               cache_level = 0;
+       }
 
        GEM_BUG_ON(vma->pages);
 
@@ -550,7 +556,7 @@ i915_vma_insert(struct i915_vma *vma, u64 size, u64 alignment, u64 flags)
                }
 
                ret = i915_gem_gtt_reserve(vma->vm, &vma->node,
-                                          size, offset, obj->cache_level,
+                                          size, offset, cache_level,
                                           flags);
                if (ret)
                        goto err_clear;
@@ -589,7 +595,7 @@ i915_vma_insert(struct i915_vma *vma, u64 size, u64 alignment, u64 flags)
                }
 
                ret = i915_gem_gtt_insert(vma->vm, &vma->node,
-                                         size, alignment, obj->cache_level,
+                                         size, alignment, cache_level,
                                          start, end, flags);
                if (ret)
                        goto err_clear;
@@ -598,23 +604,28 @@ i915_vma_insert(struct i915_vma *vma, u64 size, u64 alignment, u64 flags)
                GEM_BUG_ON(vma->node.start + vma->node.size > end);
        }
        GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
-       GEM_BUG_ON(!i915_gem_valid_gtt_space(vma, obj->cache_level));
+       GEM_BUG_ON(!i915_gem_valid_gtt_space(vma, cache_level));
 
        list_move_tail(&vma->vm_link, &vma->vm->inactive_list);
 
-       spin_lock(&dev_priv->mm.obj_lock);
-       list_move_tail(&obj->mm.link, &dev_priv->mm.bound_list);
-       obj->bind_count++;
-       spin_unlock(&dev_priv->mm.obj_lock);
+       if (vma->obj) {
+               struct drm_i915_gem_object *obj = vma->obj;
+
+               spin_lock(&dev_priv->mm.obj_lock);
+               list_move_tail(&obj->mm.link, &dev_priv->mm.bound_list);
+               obj->bind_count++;
+               spin_unlock(&dev_priv->mm.obj_lock);
 
-       assert_bind_count(obj);
+               assert_bind_count(obj);
+       }
 
        return 0;
 
 err_clear:
        vma->vm->clear_pages(vma);
 err_unpin:
-       i915_gem_object_unpin_pages(obj);
+       if (vma->obj)
+               i915_gem_object_unpin_pages(vma->obj);
        return ret;
 }
 
@@ -622,7 +633,6 @@ static void
 i915_vma_remove(struct i915_vma *vma)
 {
        struct drm_i915_private *i915 = vma->vm->i915;
-       struct drm_i915_gem_object *obj = vma->obj;
 
        GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
        GEM_BUG_ON(vma->flags & (I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND));
@@ -632,20 +642,26 @@ i915_vma_remove(struct i915_vma *vma)
        drm_mm_remove_node(&vma->node);
        list_move_tail(&vma->vm_link, &vma->vm->unbound_list);
 
-       /* Since the unbound list is global, only move to that list if
+       /*
+        * Since the unbound list is global, only move to that list if
         * no more VMAs exist.
         */
-       spin_lock(&i915->mm.obj_lock);
-       if (--obj->bind_count == 0)
-               list_move_tail(&obj->mm.link, &i915->mm.unbound_list);
-       spin_unlock(&i915->mm.obj_lock);
-
-       /* And finally now the object is completely decoupled from this vma,
-        * we can drop its hold on the backing storage and allow it to be
-        * reaped by the shrinker.
-        */
-       i915_gem_object_unpin_pages(obj);
-       assert_bind_count(obj);
+       if (vma->obj) {
+               struct drm_i915_gem_object *obj = vma->obj;
+
+               spin_lock(&i915->mm.obj_lock);
+               if (--obj->bind_count == 0)
+                       list_move_tail(&obj->mm.link, &i915->mm.unbound_list);
+               spin_unlock(&i915->mm.obj_lock);
+
+               /*
+                * And finally now the object is completely decoupled from this
+                * vma, we can drop its hold on the backing storage and allow
+                * it to be reaped by the shrinker.
+                */
+               i915_gem_object_unpin_pages(obj);
+               assert_bind_count(obj);
+       }
 }
 
 int __i915_vma_do_pin(struct i915_vma *vma,
@@ -670,7 +686,7 @@ int __i915_vma_do_pin(struct i915_vma *vma,
        }
        GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
 
-       ret = i915_vma_bind(vma, vma->obj->cache_level, flags);
+       ret = i915_vma_bind(vma, vma->obj ? vma->obj->cache_level : 0, flags);
        if (ret)
                goto err_remove;
 
@@ -727,6 +743,7 @@ void i915_vma_reopen(struct i915_vma *vma)
 
 static void __i915_vma_destroy(struct i915_vma *vma)
 {
+       struct drm_i915_private *i915 = vma->vm->i915;
        int i;
 
        GEM_BUG_ON(vma->node.allocated);
@@ -738,12 +755,13 @@ static void __i915_vma_destroy(struct i915_vma *vma)
 
        list_del(&vma->obj_link);
        list_del(&vma->vm_link);
-       rb_erase(&vma->obj_node, &vma->obj->vma_tree);
+       if (vma->obj)
+               rb_erase(&vma->obj_node, &vma->obj->vma_tree);
 
        if (!i915_vma_is_ggtt(vma))
                i915_ppgtt_put(i915_vm_to_ppgtt(vma->vm));
 
-       kmem_cache_free(to_i915(vma->obj->base.dev)->vmas, vma);
+       kmem_cache_free(i915->vmas, vma);
 }
 
 void i915_vma_destroy(struct i915_vma *vma)
@@ -809,13 +827,13 @@ void i915_vma_revoke_mmap(struct i915_vma *vma)
 
 int i915_vma_unbind(struct i915_vma *vma)
 {
-       struct drm_i915_gem_object *obj = vma->obj;
        unsigned long active;
        int ret;
 
-       lockdep_assert_held(&obj->base.dev->struct_mutex);
+       lockdep_assert_held(&vma->vm->i915->drm.struct_mutex);
 
-       /* First wait upon any activity as retiring the request may
+       /*
+        * First wait upon any activity as retiring the request may
         * have side-effects such as unpinning or even unbinding this vma.
         */
        might_sleep();
@@ -823,7 +841,8 @@ int i915_vma_unbind(struct i915_vma *vma)
        if (active) {
                int idx;
 
-               /* When a closed VMA is retired, it is unbound - eek.
+               /*
+                * When a closed VMA is retired, it is unbound - eek.
                 * In order to prevent it from being recursively closed,
                 * take a pin on the vma so that the second unbind is
                 * aborted.
@@ -861,9 +880,6 @@ int i915_vma_unbind(struct i915_vma *vma)
        if (!drm_mm_node_allocated(&vma->node))
                return 0;
 
-       GEM_BUG_ON(obj->bind_count == 0);
-       GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj));
-
        if (i915_vma_is_map_and_fenceable(vma)) {
                /*
                 * Check that we have flushed all writes through the GGTT

diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h
index fc4294cfaa91314bbfccaa75aa2692b9194c737b..f0532f1a4953d46f9d760b5d35e5feed11e2ba39 100644 (file)
--- a/drivers/gpu/drm/i915/i915_vma.h
+++ b/drivers/gpu/drm/i915/i915_vma.h
@@ -407,7 +407,7 @@ static inline void __i915_vma_unpin_fence(struct i915_vma *vma)
 static inline void
 i915_vma_unpin_fence(struct i915_vma *vma)
 {
-       lockdep_assert_held(&vma->obj->base.dev->struct_mutex);
+       /* lockdep_assert_held(&vma->vm->i915->drm.struct_mutex); */
        if (vma->fence)
                __i915_vma_unpin_fence(vma);
 }