drm/i915: Fix secure dispatch with full ppgtt

Based upon a hunk from a patch from Chris Wilson, but augmented to:
- Process the batch in the full ppgtt vm so that self-relocations
  match again with userspace's expectations..
- Add a comment why plain pin for the global gtt binding is safe at
  that point.

v2: Drop local bind_vm variable (Chris).

v3: Explain why this works despite the lack of proper active tracking
for the ggtt batch vma.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ben Widawsky <benjamin.widawsky@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Daniel Vetter 2014-08-11 12:08:58 +02:00
parent dbbe912795
commit da51a1e7e3

View file

@ -95,7 +95,6 @@ eb_lookup_vmas(struct eb_vmas *eb,
struct i915_address_space *vm,
struct drm_file *file)
{
struct drm_i915_private *dev_priv = vm->dev->dev_private;
struct drm_i915_gem_object *obj;
struct list_head objects;
int i, ret;
@ -130,7 +129,6 @@ eb_lookup_vmas(struct eb_vmas *eb,
i = 0;
while (!list_empty(&objects)) {
struct i915_vma *vma;
struct i915_address_space *bind_vm = vm;
if (exec[i].flags & EXEC_OBJECT_NEEDS_GTT &&
USES_FULL_PPGTT(vm->dev)) {
@ -138,13 +136,6 @@ eb_lookup_vmas(struct eb_vmas *eb,
goto err;
}
/* If we have secure dispatch, or the userspace assures us that
* they know what they're doing, use the GGTT VM.
*/
if (((args->flags & I915_EXEC_SECURE) &&
(i == (args->buffer_count - 1))))
bind_vm = &dev_priv->gtt.base;
obj = list_first_entry(&objects,
struct drm_i915_gem_object,
obj_exec_link);
@ -157,7 +148,7 @@ eb_lookup_vmas(struct eb_vmas *eb,
* from the (obj, vm) we don't run the risk of creating
* duplicated vmas for the same vm.
*/
vma = i915_gem_obj_lookup_or_create_vma(obj, bind_vm);
vma = i915_gem_obj_lookup_or_create_vma(obj, vm);
if (IS_ERR(vma)) {
DRM_DEBUG("Failed to lookup VMA\n");
ret = PTR_ERR(vma);
@ -1391,25 +1382,36 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
/* snb/ivb/vlv conflate the "batch in ppgtt" bit with the "non-secure
* batch" bit. Hence we need to pin secure batches into the global gtt.
* hsw should have this fixed, but bdw mucks it up again. */
if (flags & I915_DISPATCH_SECURE &&
!batch_obj->has_global_gtt_mapping) {
/* When we have multiple VMs, we'll need to make sure that we
* allocate space first */
struct i915_vma *vma = i915_gem_obj_to_ggtt(batch_obj);
BUG_ON(!vma);
vma->bind_vma(vma, batch_obj->cache_level, GLOBAL_BIND);
}
if (flags & I915_DISPATCH_SECURE) {
/*
* So on first glance it looks freaky that we pin the batch here
* outside of the reservation loop. But:
* - The batch is already pinned into the relevant ppgtt, so we
* already have the backing storage fully allocated.
* - No other BO uses the global gtt (well contexts, but meh),
* so we don't really have issues with mutliple objects not
* fitting due to fragmentation.
* So this is actually safe.
*/
ret = i915_gem_obj_ggtt_pin(batch_obj, 0, 0);
if (ret)
goto err;
if (flags & I915_DISPATCH_SECURE)
exec_start += i915_gem_obj_ggtt_offset(batch_obj);
else
} else
exec_start += i915_gem_obj_offset(batch_obj, vm);
ret = legacy_ringbuffer_submission(dev, file, ring, ctx,
args, &eb->vmas, batch_obj, exec_start, flags);
if (ret)
goto err;
args, &eb->vmas, batch_obj, exec_start, flags);
/*
* FIXME: We crucially rely upon the active tracking for the (ppgtt)
* batch vma for correctness. For less ugly and less fragility this
* needs to be adjusted to also track the ggtt batch vma properly as
* active.
*/
if (flags & I915_DISPATCH_SECURE)
i915_gem_object_ggtt_unpin(batch_obj);
err:
/* the request owns the ref now */
i915_gem_context_unreference(ctx);