drm/i915: Wrap all access to i915_vma.node.start|size

We already wrap i915_vma.node.start for use with the GGTT, as there we
can perform additional sanity checks that the node belongs to the GGTT
and fits within the 32b registers. In the next couple of patches, we
will introduce guard pages around the objects _inside_ the drm_mm_node
allocation. That is we will offset the vma->pages so that the first page
is at drm_mm_node.start + vma->guard (not 0 as is currently the case).
All users must then not use i915_vma.node.start directly, but compute
the guard offset, thus all users are converted to use a
i915_vma_offset() wrapper.

The notable exceptions are the selftests that are testing exact
behaviour of i915_vma_pin/i915_vma_insert.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Tejas Upadhyay <tejaskumarx.surendrakumar.upadhyay@intel.com>
Co-developed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221130235805.221010-3-andi.shyti@linux.intel.com

9 files changed, 49 insertions, 41 deletions

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
index 7d742f7e52b8..16618a548026 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
@@ -378,22 +378,25 @@ eb_vma_misplaced(const struct drm_i915_gem_exec_object2 *entry,
 		 const struct i915_vma *vma,
 		 unsigned int flags)
 {
-	if (vma->node.size < entry->pad_to_size)
+	const u64 start = i915_vma_offset(vma);
+	const u64 size = i915_vma_size(vma);
+
+	if (size < entry->pad_to_size)
 		return true;
 
-	if (entry->alignment && !IS_ALIGNED(vma->node.start, entry->alignment))
+	if (entry->alignment && !IS_ALIGNED(start, entry->alignment))
 		return true;
 
 	if (flags & EXEC_OBJECT_PINNED &&
-	    vma->node.start != entry->offset)
+	    start != entry->offset)
 		return true;
 
 	if (flags & __EXEC_OBJECT_NEEDS_BIAS &&
-	    vma->node.start < BATCH_OFFSET_BIAS)
+	    start < BATCH_OFFSET_BIAS)
 		return true;
 
 	if (!(flags & EXEC_OBJECT_SUPPORTS_48B_ADDRESS) &&
-	    (vma->node.start + vma->node.size + 4095) >> 32)
+	    (start + size + 4095) >> 32)
 		return true;
 
 	if (flags & __EXEC_OBJECT_NEEDS_MAP &&
@@ -439,7 +442,7 @@ eb_pin_vma(struct i915_execbuffer *eb,
 	int err;
 
 	if (vma->node.size)
-		pin_flags = vma->node.start;
+		pin_flags =  __i915_vma_offset(vma);
 	else
 		pin_flags = entry->offset & PIN_OFFSET_MASK;
 
@@ -662,8 +665,8 @@ static int eb_reserve_vma(struct i915_execbuffer *eb,
 	if (err)
 		return err;
 
-	if (entry->offset != vma->node.start) {
-		entry->offset = vma->node.start | UPDATE;
+	if (entry->offset != i915_vma_offset(vma)) {
+		entry->offset = i915_vma_offset(vma) | UPDATE;
 		eb->args->flags |= __EXEC_HAS_RELOC;
 	}
 
@@ -983,8 +986,8 @@ static int eb_validate_vmas(struct i915_execbuffer *eb)
 			return err;
 
 		if (!err) {
-			if (entry->offset != vma->node.start) {
-				entry->offset = vma->node.start | UPDATE;
+			if (entry->offset != i915_vma_offset(vma)) {
+				entry->offset = i915_vma_offset(vma) | UPDATE;
 				eb->args->flags |= __EXEC_HAS_RELOC;
 			}
 		} else {
@@ -1065,7 +1068,7 @@ static inline u64
 relocation_target(const struct drm_i915_gem_relocation_entry *reloc,
 		  const struct i915_vma *target)
 {
-	return gen8_canonical_addr((int)reloc->delta + target->node.start);
+	return gen8_canonical_addr((int)reloc->delta + i915_vma_offset(target));
 }
 
 static void reloc_cache_init(struct reloc_cache *cache,
@@ -1274,7 +1277,7 @@ static void *reloc_iomap(struct i915_vma *batch,
 			if (err) /* no inactive aperture space, use cpu reloc */
 				return NULL;
 		} else {
-			cache->node.start = vma->node.start;
+			cache->node.start = i915_ggtt_offset(vma);
 			cache->node.mm = (void *)vma;
 		}
 	}
@@ -1437,7 +1440,7 @@ eb_relocate_entry(struct i915_execbuffer *eb,
 	 * more work needs to be done.
 	 */
 	if (!DBG_FORCE_RELOC &&
-	    gen8_canonical_addr(target->vma->node.start) == reloc->presumed_offset)
+	    gen8_canonical_addr(i915_vma_offset(target->vma)) == reloc->presumed_offset)
 		return 0;
 
 	/* Check that the relocation address is valid... */
@@ -2367,7 +2370,7 @@ static int eb_request_submit(struct i915_execbuffer *eb,
 	}
 
 	err = rq->context->engine->emit_bb_start(rq,
-						 batch->node.start +
+						 i915_vma_offset(batch) +
 						 eb->batch_start_offset,
 						 batch_len,
 						 eb->batch_flags);
@@ -2378,7 +2381,7 @@ static int eb_request_submit(struct i915_execbuffer *eb,
 		GEM_BUG_ON(intel_context_is_parallel(rq->context));
 		GEM_BUG_ON(eb->batch_start_offset);
 		err = rq->context->engine->emit_bb_start(rq,
-							 eb->trampoline->node.start +
+							 i915_vma_offset(eb->trampoline) +
 							 batch_len, 0, 0);
 		if (err)
 			return err;
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index c29efdef8313..d73ba0f5c4c5 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -395,7 +395,7 @@ retry:
 	/* Finally, remap it using the new GTT offset */
 	ret = remap_io_mapping(area,
 			       area->vm_start + (vma->gtt_view.partial.offset << PAGE_SHIFT),
-			       (ggtt->gmadr.start + vma->node.start) >> PAGE_SHIFT,
+			       (ggtt->gmadr.start + i915_ggtt_offset(vma)) >> PAGE_SHIFT,
 			       min_t(u64, vma->size, area->vm_end - area->vm_start),
 			       &ggtt->iomap);
 	if (ret)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c b/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c
index 8dc5c8874d8a..b1672e054b21 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c
@@ -400,7 +400,7 @@ i915_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr
 	mutex_lock(&to_gt(i915)->ggtt->vm.mutex);
 	list_for_each_entry_safe(vma, next,
 				 &to_gt(i915)->ggtt->vm.bound_list, vm_link) {
-		unsigned long count = vma->node.size >> PAGE_SHIFT;
+		unsigned long count = i915_vma_size(vma) >> PAGE_SHIFT;
 		struct drm_i915_gem_object *obj = vma->obj;
 
 		if (!vma->iomap || i915_vma_is_active(vma))
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_tiling.c b/drivers/gpu/drm/i915/gem/i915_gem_tiling.c
index fd42b89b7162..04bb909acdec 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_tiling.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_tiling.c
@@ -168,11 +168,11 @@ static bool i915_vma_fence_prepare(struct i915_vma *vma,
 		return true;
 
 	size = i915_gem_fence_size(i915, vma->size, tiling_mode, stride);
-	if (vma->node.size < size)
+	if (i915_vma_size(vma) < size)
 		return false;
 
 	alignment = i915_gem_fence_alignment(i915, vma->size, tiling_mode, stride);
-	if (!IS_ALIGNED(vma->node.start, alignment))
+	if (!IS_ALIGNED(i915_ggtt_offset(vma), alignment))
 		return false;
 
 	return true;
diff --git a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c b/drivers/gpu/drm/i915/gem/selftests/huge_pages.c
index beaf27e09e8a..e0c2ac9c8053 100644
--- a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c
+++ b/drivers/gpu/drm/i915/gem/selftests/huge_pages.c
@@ -400,7 +400,7 @@ static int igt_check_page_sizes(struct i915_vma *vma)
 	 * Maintaining alignment is required to utilise huge pages in the ppGGT.
 	 */
 	if (i915_gem_object_is_lmem(obj) &&
-	    IS_ALIGNED(vma->node.start, SZ_2M) &&
+	    IS_ALIGNED(i915_vma_offset(vma), SZ_2M) &&
 	    vma->page_sizes.sg & SZ_2M &&
 	    vma->resource->page_sizes_gtt < SZ_2M) {
 		pr_err("gtt pages mismatch for LMEM, expected 2M GTT pages, sg(%u), gtt(%u)\n",
diff --git a/drivers/gpu/drm/i915/gem/selftests/i915_gem_client_blt.c b/drivers/gpu/drm/i915/gem/selftests/i915_gem_client_blt.c
index 692a16914ca0..3bb1f7f0110e 100644
--- a/drivers/gpu/drm/i915/gem/selftests/i915_gem_client_blt.c
+++ b/drivers/gpu/drm/i915/gem/selftests/i915_gem_client_blt.c
@@ -194,12 +194,12 @@ static int prepare_blit(const struct tiled_blits *t,
 		*cs++ = src_4t | dst_4t | BLT_DEPTH_32 | dst_pitch;
 		*cs++ = 0;
 		*cs++ = t->height << 16 | t->width;
-		*cs++ = lower_32_bits(dst->vma->node.start);
-		*cs++ = upper_32_bits(dst->vma->node.start);
+		*cs++ = lower_32_bits(i915_vma_offset(dst->vma));
+		*cs++ = upper_32_bits(i915_vma_offset(dst->vma));
 		*cs++ = 0;
 		*cs++ = src_pitch;
-		*cs++ = lower_32_bits(src->vma->node.start);
-		*cs++ = upper_32_bits(src->vma->node.start);
+		*cs++ = lower_32_bits(i915_vma_offset(src->vma));
+		*cs++ = upper_32_bits(i915_vma_offset(src->vma));
 	} else {
 		if (ver >= 6) {
 			*cs++ = MI_LOAD_REGISTER_IMM(1);
@@ -240,14 +240,14 @@ static int prepare_blit(const struct tiled_blits *t,
 		*cs++ = BLT_DEPTH_32 | BLT_ROP_SRC_COPY | dst_pitch;
 		*cs++ = 0;
 		*cs++ = t->height << 16 | t->width;
-		*cs++ = lower_32_bits(dst->vma->node.start);
+		*cs++ = lower_32_bits(i915_vma_offset(dst->vma));
 		if (use_64b_reloc)
-			*cs++ = upper_32_bits(dst->vma->node.start);
+			*cs++ = upper_32_bits(i915_vma_offset(dst->vma));
 		*cs++ = 0;
 		*cs++ = src_pitch;
-		*cs++ = lower_32_bits(src->vma->node.start);
+		*cs++ = lower_32_bits(i915_vma_offset(src->vma));
 		if (use_64b_reloc)
-			*cs++ = upper_32_bits(src->vma->node.start);
+			*cs++ = upper_32_bits(i915_vma_offset(src->vma));
 	}
 
 	*cs++ = MI_BATCH_BUFFER_END;
@@ -462,7 +462,7 @@ static int pin_buffer(struct i915_vma *vma, u64 addr)
 {
 	int err;
 
-	if (drm_mm_node_allocated(&vma->node) && vma->node.start != addr) {
+	if (drm_mm_node_allocated(&vma->node) && i915_vma_offset(vma) != addr) {
 		err = i915_vma_unbind_unlocked(vma);
 		if (err)
 			return err;
@@ -472,6 +472,7 @@ static int pin_buffer(struct i915_vma *vma, u64 addr)
 	if (err)
 		return err;
 
+	GEM_BUG_ON(i915_vma_offset(vma) != addr);
 	return 0;
 }
 
@@ -518,8 +519,8 @@ tiled_blit(struct tiled_blits *t,
 		err = igt_vma_move_to_active_unlocked(dst->vma, rq, 0);
 	if (!err)
 		err = rq->engine->emit_bb_start(rq,
-						t->batch->node.start,
-						t->batch->node.size,
+						i915_vma_offset(t->batch),
+						i915_vma_size(t->batch),
 						0);
 	i915_request_get(rq);
 	i915_request_add(rq);
diff --git a/drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c b/drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c
index a0ff51d71d07..ac02fb036592 100644
--- a/drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c
@@ -914,8 +914,8 @@ static int rpcs_query_batch(struct drm_i915_gem_object *rpcs,
 
 	*cmd++ = MI_STORE_REGISTER_MEM_GEN8;
 	*cmd++ = i915_mmio_reg_offset(GEN8_R_PWR_CLK_STATE(engine->mmio_base));
-	*cmd++ = lower_32_bits(vma->node.start);
-	*cmd++ = upper_32_bits(vma->node.start);
+	*cmd++ = lower_32_bits(i915_vma_offset(vma));
+	*cmd++ = upper_32_bits(i915_vma_offset(vma));
 	*cmd = MI_BATCH_BUFFER_END;
 
 	__i915_gem_object_flush_map(rpcs, 0, 64);
@@ -999,7 +999,8 @@ retry:
 	}
 
 	err = rq->engine->emit_bb_start(rq,
-					batch->node.start, batch->node.size,
+					i915_vma_offset(batch),
+					i915_vma_size(batch),
 					0);
 	if (err)
 		goto skip_request;
@@ -1560,7 +1561,8 @@ static int write_to_scratch(struct i915_gem_context *ctx,
 			goto skip_request;
 	}
 
-	err = engine->emit_bb_start(rq, vma->node.start, vma->node.size, 0);
+	err = engine->emit_bb_start(rq, i915_vma_offset(vma),
+				    i915_vma_size(vma), 0);
 	if (err)
 		goto skip_request;
 
@@ -1665,7 +1667,7 @@ static int read_from_scratch(struct i915_gem_context *ctx,
 		*cmd++ = offset;
 		*cmd++ = MI_STORE_REGISTER_MEM | MI_USE_GGTT;
 		*cmd++ = reg;
-		*cmd++ = vma->node.start + result;
+		*cmd++ = i915_vma_offset(vma) + result;
 		*cmd = MI_BATCH_BUFFER_END;
 
 		i915_gem_object_flush_map(obj);
@@ -1694,7 +1696,8 @@ static int read_from_scratch(struct i915_gem_context *ctx,
 			goto skip_request;
 	}
 
-	err = engine->emit_bb_start(rq, vma->node.start, vma->node.size, flags);
+	err = engine->emit_bb_start(rq, i915_vma_offset(vma),
+				    i915_vma_size(vma), flags);
 	if (err)
 		goto skip_request;
 
diff --git a/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c
index 80e7fdd5d164..c04d317df96d 100644
--- a/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c
@@ -1608,7 +1608,7 @@ retry:
 
 		err = i915_vma_move_to_active(vma, rq, 0);
 
-		err = engine->emit_bb_start(rq, vma->node.start, 0, 0);
+		err = engine->emit_bb_start(rq, i915_vma_offset(vma), 0, 0);
 		i915_request_get(rq);
 		i915_request_add(rq);
 
diff --git a/drivers/gpu/drm/i915/gem/selftests/igt_gem_utils.c b/drivers/gpu/drm/i915/gem/selftests/igt_gem_utils.c
index 374b10ac430e..c147038230c4 100644
--- a/drivers/gpu/drm/i915/gem/selftests/igt_gem_utils.c
+++ b/drivers/gpu/drm/i915/gem/selftests/igt_gem_utils.c
@@ -62,8 +62,8 @@ igt_emit_store_dw(struct i915_vma *vma,
 		goto err;
 	}
 
-	GEM_BUG_ON(offset + (count - 1) * PAGE_SIZE > vma->node.size);
-	offset += vma->node.start;
+	GEM_BUG_ON(offset + (count - 1) * PAGE_SIZE > i915_vma_size(vma));
+	offset += i915_vma_offset(vma);
 
 	for (n = 0; n < count; n++) {
 		if (ver >= 8) {
@@ -147,7 +147,8 @@ int igt_gpu_fill_dw(struct intel_context *ce,
 		flags |= I915_DISPATCH_SECURE;
 
 	err = rq->engine->emit_bb_start(rq,
-					batch->node.start, batch->node.size,
+					i915_vma_offset(batch),
+					i915_vma_size(batch),
 					flags);
 
 skip_request: