[PATCH v4 34/38] drm: Wrap drm_mm_node.hole_follows

Chris Wilson
2016-12-22T08:36:37Z

Insulate users from changes to the internal hole tracking within
struct drm_mm_node by using an accessor for hole_follows.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
---
drivers/gpu/drm/drm_mm.c | 12 ++++++------
drivers/gpu/drm/i915/i915_vma.c | 4 ++--
drivers/gpu/drm/selftests/test-drm_mm.c | 18 ++++++++++--------
include/drm/drm_mm.h | 22 +++++++++++++++++++---
4 files changed, 37 insertions(+), 19 deletions(-)

diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c
index b59978fe4c6e..c0024719f32b 100644
--- a/drivers/gpu/drm/drm_mm.c
+++ b/drivers/gpu/drm/drm_mm.c
@@ -323,7 +323,7 @@ int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node)
}

hole = list_last_entry(&hole->node_list, typeof(*hole), node_list);
- if (!hole->hole_follows)
+ if (!drm_mm_hole_follows(hole))
return -ENOSPC;

adj_start = hole_start = __drm_mm_hole_node_start(hole);
@@ -408,7 +408,7 @@ static void drm_mm_insert_helper_range(struct drm_mm_node *hole_node,
u64 adj_start = hole_start;
u64 adj_end = hole_end;

- DRM_MM_BUG_ON(!hole_node->hole_follows || node->allocated);
+ DRM_MM_BUG_ON(!drm_mm_hole_follows(hole_node) || node->allocated);

if (adj_start < start)
adj_start = start;
@@ -523,16 +523,16 @@ void drm_mm_remove_node(struct drm_mm_node *node)
prev_node =
list_entry(node->node_list.prev, struct drm_mm_node, node_list);

- if (node->hole_follows) {
+ if (drm_mm_hole_follows(node)) {
DRM_MM_BUG_ON(__drm_mm_hole_node_start(node) ==
__drm_mm_hole_node_end(node));
list_del(&node->hole_stack);
- } else
+ } else {
DRM_MM_BUG_ON(__drm_mm_hole_node_start(node) !=
__drm_mm_hole_node_end(node));
+ }

-
- if (!prev_node->hole_follows) {
+ if (!drm_mm_hole_follows(prev_node)) {
prev_node->hole_follows = 1;
list_add(&prev_node->hole_stack, &mm->hole_stack);
} else
diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
index 608008d2d999..cfec4222b04e 100644
--- a/drivers/gpu/drm/i915/i915_vma.c
+++ b/drivers/gpu/drm/i915/i915_vma.c
@@ -327,11 +327,11 @@ bool i915_gem_valid_gtt_space(struct i915_vma *vma, unsigned long cache_level)
GEM_BUG_ON(list_empty(&node->node_list));

other = list_prev_entry(node, node_list);
- if (color_differs(other, cache_level) && !other->hole_follows)
+ if (color_differs(other, cache_level) && !drm_mm_hole_follows(other))
return false;

other = list_next_entry(node, node_list);
- if (color_differs(other, cache_level) && !node->hole_follows)
+ if (color_differs(other, cache_level) && !drm_mm_hole_follows(node))
return false;

return true;
diff --git a/drivers/gpu/drm/selftests/test-drm_mm.c b/drivers/gpu/drm/selftests/test-drm_mm.c
index f609e4f1eeaf..2ce92f4dcfc7 100644
--- a/drivers/gpu/drm/selftests/test-drm_mm.c
+++ b/drivers/gpu/drm/selftests/test-drm_mm.c
@@ -63,7 +63,7 @@ static bool assert_no_holes(const struct drm_mm *mm)
}

drm_mm_for_each_node(hole, mm) {
- if (hole->hole_follows) {
+ if (drm_mm_hole_follows(hole)) {
pr_err("Hole follows node, expected none!\n");
return false;
}
@@ -125,7 +125,7 @@ static bool assert_continuous(const struct drm_mm *mm, u64 size)
return false;
}

- if (node->hole_follows) {
+ if (drm_mm_hole_follows(node)) {
pr_err("node[%ld] is followed by a hole!\n", n);
return false;
}
@@ -828,7 +828,8 @@ static bool assert_contiguous_in_range(struct drm_mm *mm,
return false;
}

- if (node->hole_follows && drm_mm_hole_node_end(node) < end) {
+ if (drm_mm_hole_follows(node) &&
+ drm_mm_hole_node_end(node) < end) {
pr_err("node %d is followed by a hole!\n", n);
return false;
}
@@ -1337,11 +1338,12 @@ static int evict_something(struct drm_mm *mm,
err = -EINVAL;
}

- if (!assert_node(&tmp, mm, size, alignment, 0) || tmp.hole_follows) {
+ if (!assert_node(&tmp, mm, size, alignment, 0) ||
+ drm_mm_hole_follows(&tmp)) {
pr_err("Inserted did not fill the eviction hole: size=%lld [%d], align=%d [rem=%lld], start=%llx, hole-follows?=%d\n",
tmp.size, size,
alignment, misalignment(&tmp, alignment),
- tmp.start, tmp.hole_follows);
+ tmp.start, drm_mm_hole_follows(&tmp));
err = -EINVAL;
}

@@ -1618,7 +1620,7 @@ static int igt_topdown(void *ignored)
goto out;
}

- if (nodes[n].hole_follows) {
+ if (drm_mm_hole_follows(&nodes[n])) {
pr_err("hole after topdown insert %d, start=%llx\n, size=%u",
n, nodes[n].start, size);
goto out;
@@ -1650,7 +1652,7 @@ static int igt_topdown(void *ignored)
goto out;
}

- if (node->hole_follows) {
+ if (drm_mm_hole_follows(node)) {
pr_err("hole after topdown insert %d/%d, start=%llx\n",
m, n, node->start);
goto out;
@@ -1705,7 +1707,7 @@ static void separate_adjacent_colors(const struct drm_mm_node *node,

static bool colors_abutt(const struct drm_mm_node *node)
{
- if (!node->hole_follows &&
+ if (!drm_mm_hole_follows(node) &&
list_next_entry(node, node_list)->allocated) {
pr_err("colors abutt; %ld [%llx + %llx] is next to %ld [%llx + %llx]!\n",
node->color, node->start, node->size,
diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h
index aed93cbc4bde..7da7a171d6d5 100644
--- a/include/drm/drm_mm.h
+++ b/include/drm/drm_mm.h
@@ -155,6 +155,22 @@ static inline bool drm_mm_initialized(const struct drm_mm *mm)
return mm->hole_stack.next;
}

+/**
+ * drm_mm_hole_follows - checks whether a hole follows this node
+ * @node: drm_mm_node to check
+ *
+ * Holes are embedded into the drm_mm using the tail of a drm_mm_node.
+ * If you wish to know whether a hole follows this particular node,
+ * query this function.
+ *
+ * Returns:
+ * True if a hole follows the @node.
+ */
+static inline bool drm_mm_hole_follows(const struct drm_mm_node *node)
+{
+ return node->hole_follows;
+}
+
static inline u64 __drm_mm_hole_node_start(const struct drm_mm_node *hole_node)
{
return hole_node->start + hole_node->size;
@@ -166,14 +182,14 @@ static inline u64 __drm_mm_hole_node_start(const struct drm_mm_node *hole_node)
*
* This is useful for driver-specific debug dumpers. Otherwise drivers should
* not inspect holes themselves. Drivers must check first whether a hole indeed
- * follows by looking at node->hole_follows.
+ * follows by looking at drm_mm_hole_follows()
*
* Returns:
* Start of the subsequent hole.
*/
static inline u64 drm_mm_hole_node_start(const struct drm_mm_node *hole_node)
{
- DRM_MM_BUG_ON(!hole_node->hole_follows);
+ DRM_MM_BUG_ON(!drm_mm_hole_follows(hole_node));
return __drm_mm_hole_node_start(hole_node);
}

@@ -188,7 +204,7 @@ static inline u64 __drm_mm_hole_node_end(const struct drm_mm_node *hole_node)
*
* This is useful for driver-specific debug dumpers. Otherwise drivers should
* not inspect holes themselves. Drivers must check first whether a hole indeed
- * follows by looking at node->hole_follows.
+ * follows by looking at drm_mm_hole_follows().
*
* Returns:
* End of the subsequent hole.