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, 3 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h
index 9a931ecb09e5..32719431b3df 100644
--- a/drivers/gpu/drm/i915/i915_vma.h
+++ b/drivers/gpu/drm/i915/i915_vma.h
@@ -431,4 +431,7 @@ static inline int i915_vma_sync(struct i915_vma *vma)
 void i915_vma_module_exit(void);
 int i915_vma_module_init(void);
 
+I915_SELFTEST_DECLARE(int i915_vma_get_pages(struct i915_vma *vma));
+I915_SELFTEST_DECLARE(void i915_vma_put_pages(struct i915_vma *vma));
+
 #endif