drm/i915: Release vma when the handle is closed
In order to prevent a leak of the vma on shared objects, we need to
hook into the object_close callback to destroy the vma on the object for
this file. However, if we destroyed that vma immediately we may cause
unexpected application stalls as we try to unbind a busy vma - hence we
defer the unbind to when we retire the vma.
v2: Keep vma allocated until closed. This is useful for a later
optimisation, but it is required now in order to handle potential
recursion of i915_vma_unbind() by retiring itself.
v3: Comments are important.
Testcase: igt/gem_ppggtt/flink-and-close-vma-leak
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470293567-10811-26-git-send-email-chris@chris-wilson.co.uk
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 51660ce..5a66ad4b 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2596,6 +2596,19 @@
}
}
+void i915_gem_close_object(struct drm_gem_object *gem, struct drm_file *file)
+{
+ struct drm_i915_gem_object *obj = to_intel_bo(gem);
+ struct drm_i915_file_private *fpriv = file->driver_priv;
+ struct i915_vma *vma, *vn;
+
+ mutex_lock(&obj->base.dev->struct_mutex);
+ list_for_each_entry_safe(vma, vn, &obj->vma_list, obj_link)
+ if (vma->vm->file == fpriv)
+ i915_vma_close(vma);
+ mutex_unlock(&obj->base.dev->struct_mutex);
+}
+
/**
* i915_gem_wait_ioctl - implements DRM_IOCTL_I915_GEM_WAIT
* @dev: drm device pointer
@@ -2803,26 +2816,32 @@
if (active && wait) {
int idx;
+ /* 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.
+ */
+ vma->pin_count++;
+
for_each_active(active, idx) {
ret = i915_gem_active_retire(&vma->last_read[idx],
&vma->vm->dev->struct_mutex);
if (ret)
- return ret;
+ break;
}
+ vma->pin_count--;
+ if (ret)
+ return ret;
+
GEM_BUG_ON(i915_vma_is_active(vma));
}
if (vma->pin_count)
return -EBUSY;
- if (list_empty(&vma->obj_link))
- return 0;
-
- if (!drm_mm_node_allocated(&vma->node)) {
- i915_gem_vma_destroy(vma);
- return 0;
- }
+ if (!drm_mm_node_allocated(&vma->node))
+ goto destroy;
GEM_BUG_ON(obj->bind_count == 0);
GEM_BUG_ON(!obj->pages);
@@ -2855,7 +2874,6 @@
}
drm_mm_remove_node(&vma->node);
- i915_gem_vma_destroy(vma);
/* Since the unbound list is global, only move to that list if
* no more VMAs exist. */
@@ -2869,6 +2887,10 @@
*/
i915_gem_object_unpin_pages(obj);
+destroy:
+ if (unlikely(vma->closed))
+ i915_vma_destroy(vma);
+
return 0;
}
@@ -3043,7 +3065,7 @@
if (offset & (alignment - 1) || offset + size > end) {
ret = -EINVAL;
- goto err_free_vma;
+ goto err_vma;
}
vma->node.start = offset;
vma->node.size = size;
@@ -3055,7 +3077,7 @@
ret = drm_mm_reserve_node(&vm->mm, &vma->node);
}
if (ret)
- goto err_free_vma;
+ goto err_vma;
} else {
if (flags & PIN_HIGH) {
search_flag = DRM_MM_SEARCH_BELOW;
@@ -3080,7 +3102,7 @@
if (ret == 0)
goto search_free;
- goto err_free_vma;
+ goto err_vma;
}
}
if (WARN_ON(!i915_gem_valid_gtt_space(vma, obj->cache_level))) {
@@ -3101,8 +3123,7 @@
err_remove_node:
drm_mm_remove_node(&vma->node);
-err_free_vma:
- i915_gem_vma_destroy(vma);
+err_vma:
vma = ERR_PTR(ret);
err_unpin:
i915_gem_object_unpin_pages(obj);
@@ -4051,21 +4072,18 @@
trace_i915_gem_object_destroy(obj);
+ /* All file-owned VMA should have been released by this point through
+ * i915_gem_close_object(), or earlier by i915_gem_context_close().
+ * However, the object may also be bound into the global GTT (e.g.
+ * older GPUs without per-process support, or for direct access through
+ * the GTT either for the user or for scanout). Those VMA still need to
+ * unbound now.
+ */
list_for_each_entry_safe(vma, next, &obj->vma_list, obj_link) {
- int ret;
-
+ GEM_BUG_ON(!vma->is_ggtt);
+ GEM_BUG_ON(i915_vma_is_active(vma));
vma->pin_count = 0;
- ret = __i915_vma_unbind_no_wait(vma);
- if (WARN_ON(ret == -ERESTARTSYS)) {
- bool was_interruptible;
-
- was_interruptible = dev_priv->mm.interruptible;
- dev_priv->mm.interruptible = false;
-
- WARN_ON(i915_vma_unbind(vma));
-
- dev_priv->mm.interruptible = was_interruptible;
- }
+ i915_vma_close(vma);
}
GEM_BUG_ON(obj->bind_count);
@@ -4129,22 +4147,6 @@
return NULL;
}
-void i915_gem_vma_destroy(struct i915_vma *vma)
-{
- WARN_ON(vma->node.allocated);
-
- /* Keep the vma as a placeholder in the execbuffer reservation lists */
- if (!list_empty(&vma->exec_list))
- return;
-
- if (!vma->is_ggtt)
- i915_ppgtt_put(i915_vm_to_ppgtt(vma->vm));
-
- list_del(&vma->obj_link);
-
- kmem_cache_free(to_i915(vma->obj->base.dev)->vmas, vma);
-}
-
static void
i915_gem_stop_engines(struct drm_device *dev)
{