[Intel-gfx] [PATCH] [v2] drm/i915/ppgtt: Never return a NULL context

[Ben Widawsky]

It makes all the code which calls into this function way too confusing.

v2: Fix destroy IOCTL as well

v3: Clarify the other two callers of i915_gem_context_get() to never
check for NULL. (Mika)

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=72903
Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
---
 drivers/gpu/drm/i915/i915_gem_context.c    | 12 +++++++++---
 drivers/gpu/drm/i915/i915_gem_execbuffer.c |  4 ++--
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index ebe0f67..44dddc00 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -526,10 +526,16 @@ void i915_gem_context_close(struct drm_device *dev, struct drm_file *file)
 struct i915_hw_context *
 i915_gem_context_get(struct drm_i915_file_private *file_priv, u32 id)
 {
+	struct i915_hw_context *ctx;
+
 	if (!HAS_HW_CONTEXTS(file_priv->dev_priv->dev))
 		return file_priv->private_default_ctx;
 
-	return (struct i915_hw_context *)idr_find(&file_priv->context_idr, id);
+	ctx = (struct i915_hw_context *)idr_find(&file_priv->context_idr, id);
+	if (!ctx)
+		return ERR_PTR(-ENOENT);
+
+	return ctx;
 }
 
 static inline int
@@ -776,9 +782,9 @@ int i915_gem_context_destroy_ioctl(struct drm_device *dev, void *data,
 		return ret;
 
 	ctx = i915_gem_context_get(file_priv, args->ctx_id);
-	if (!ctx) {
+	if (IS_ERR(ctx)) {
 		mutex_unlock(&dev->struct_mutex);
-		return -ENOENT;
+		return PTR_ERR(ctx);
 	}
 
 	idr_remove(&ctx->file_priv->context_idr, ctx->id);
diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index bbff8f9..c30a6ee 100644
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -916,7 +916,7 @@ i915_gem_validate_context(struct drm_device *dev, struct drm_file *file,
 		return ERR_PTR(-EINVAL);
 
 	ctx = i915_gem_context_get(file->driver_priv, ctx_id);
-	if (IS_ERR_OR_NULL(ctx))
+	if (IS_ERR(ctx))
 		return ctx;
 
 	hs = &ctx->hang_stats;
@@ -1126,7 +1126,7 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
 	}
 
 	ctx = i915_gem_validate_context(dev, file, ring, ctx_id);
-	if (IS_ERR_OR_NULL(ctx)) {
+	if (IS_ERR(ctx)) {
 		mutex_unlock(&dev->struct_mutex);
 		ret = PTR_ERR(ctx);
 		goto pre_mutex_err;
-- 
1.8.5.2