drm/i915: Remove pages_mutex and intel_gtt->vma_ops.set/clear_pages members, v3.

Big delta, but boils down to moving set_pages to i915_vma.c, and removing
the special handling, all callers use the defaults anyway. We only remap
in ggtt, so default case will fall through.

Because we still don't require locking in i915_vma_unpin(), handle this by
using xchg in get_pages(), as it's locked with obj->mutex, and cmpxchg in
unpin, which only fails if we race a against a new pin.

Changes since v1:
- aliasing gtt sets ZERO_SIZE_PTR, not -ENODEV, remove special case
  from __i915_vma_get_pages(). (Matt)
Changes since v2:
- Free correct old pages in __i915_vma_get_pages(). (Matt)
  Remove race of clearing vma->pages accidentally from put,
  free it but leave it set, as only get has the lock.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211216142749.1966107-4-maarten.lankhorst@linux.intel.com
Reviewed-by: Matthew Auld <matthew.auld@intel.com>

1 files changed, 0 insertions, 15 deletions

diff --git a/drivers/gpu/drm/i915/gt/gen6_ppgtt.c b/drivers/gpu/drm/i915/gt/gen6_ppgtt.c
index c0d149f04949..6e9292918bfc 100644
--- a/drivers/gpu/drm/i915/gt/gen6_ppgtt.c
+++ b/drivers/gpu/drm/i915/gt/gen6_ppgtt.c
@@ -269,19 +269,6 @@ static void gen6_ppgtt_cleanup(struct i915_address_space *vm)
 	free_pd(&ppgtt->base.vm, ppgtt->base.pd);
 }
 
-static int pd_vma_set_pages(struct i915_vma *vma)
-{
-	vma->pages = ERR_PTR(-ENODEV);
-	return 0;
-}
-
-static void pd_vma_clear_pages(struct i915_vma *vma)
-{
-	GEM_BUG_ON(!vma->pages);
-
-	vma->pages = NULL;
-}
-
 static void pd_vma_bind(struct i915_address_space *vm,
 			struct i915_vm_pt_stash *stash,
 			struct i915_vma *vma,
@@ -321,8 +308,6 @@ static void pd_vma_unbind(struct i915_address_space *vm, struct i915_vma *vma)
 }
 
 static const struct i915_vma_ops pd_vma_ops = {
-	.set_pages = pd_vma_set_pages,
-	.clear_pages = pd_vma_clear_pages,
 	.bind_vma = pd_vma_bind,
 	.unbind_vma = pd_vma_unbind,
 };