From 7e109615f807173d2c7b28ef9c55e1ae639166b5 Mon Sep 17 00:00:00 2001
From: Jason Ekstrand <jason@jlekstrand.net>
Date: Thu, 8 Jul 2021 10:48:13 -0500
Subject: drm/i915: Drop getparam support for I915_CONTEXT_PARAM_ENGINES
Git-commit: c7a71fc8ee04669037501da2f987f0732e8754ee
Patch-mainline: v5.15-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

This has never been used by any userspace except IGT and provides no
real functionality beyond parroting back parameters userspace passed in
as part of context creation or via setparam.  If the context is in
legacy mode (where you use I915_EXEC_RENDER and friends), it returns
success with zero data so it's not useful for discovering what engines
are in the context.  It's also not a replacement for the recently
removed I915_CONTEXT_CLONE_ENGINES because it doesn't return any of the
balancing or bonding information.

Signed-off-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210708154835.528166-9-jason@jlekstrand.net
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/i915/gem/i915_gem_context.c | 77 +--------------------
 1 file changed, 1 insertion(+), 76 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c
index 249bd36f1401..e36e3b1ae14e 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
@@ -1724,78 +1724,6 @@ set_engines(struct i915_gem_context *ctx,
 	return 0;
 }
 
-static int
-get_engines(struct i915_gem_context *ctx,
-	    struct drm_i915_gem_context_param *args)
-{
-	struct i915_context_param_engines __user *user;
-	struct i915_gem_engines *e;
-	size_t n, count, size;
-	bool user_engines;
-	int err = 0;
-
-	e = __context_engines_await(ctx, &user_engines);
-	if (!e)
-		return -ENOENT;
-
-	if (!user_engines) {
-		i915_sw_fence_complete(&e->fence);
-		args->size = 0;
-		return 0;
-	}
-
-	count = e->num_engines;
-
-	/* Be paranoid in case we have an impedance mismatch */
-	if (!check_struct_size(user, engines, count, &size)) {
-		err = -EINVAL;
-		goto err_free;
-	}
-	if (overflows_type(size, args->size)) {
-		err = -EINVAL;
-		goto err_free;
-	}
-
-	if (!args->size) {
-		args->size = size;
-		goto err_free;
-	}
-
-	if (args->size < size) {
-		err = -EINVAL;
-		goto err_free;
-	}
-
-	user = u64_to_user_ptr(args->value);
-	if (put_user(0, &user->extensions)) {
-		err = -EFAULT;
-		goto err_free;
-	}
-
-	for (n = 0; n < count; n++) {
-		struct i915_engine_class_instance ci = {
-			.engine_class = I915_ENGINE_CLASS_INVALID,
-			.engine_instance = I915_ENGINE_CLASS_INVALID_NONE,
-		};
-
-		if (e->engines[n]) {
-			ci.engine_class = e->engines[n]->engine->uabi_class;
-			ci.engine_instance = e->engines[n]->engine->uabi_instance;
-		}
-
-		if (copy_to_user(&user->engines[n], &ci, sizeof(ci))) {
-			err = -EFAULT;
-			goto err_free;
-		}
-	}
-
-	args->size = size;
-
-err_free:
-	i915_sw_fence_complete(&e->fence);
-	return err;
-}
-
 static int
 set_persistence(struct i915_gem_context *ctx,
 		const struct drm_i915_gem_context_param *args)
@@ -2126,10 +2054,6 @@ int i915_gem_context_getparam_ioctl(struct drm_device *dev, void *data,
 		ret = get_ppgtt(file_priv, ctx, args);
 		break;
 
-	case I915_CONTEXT_PARAM_ENGINES:
-		ret = get_engines(ctx, args);
-		break;
-
 	case I915_CONTEXT_PARAM_PERSISTENCE:
 		args->size = 0;
 		args->value = i915_gem_context_is_persistent(ctx);
@@ -2137,6 +2061,7 @@ int i915_gem_context_getparam_ioctl(struct drm_device *dev, void *data,
 
 	case I915_CONTEXT_PARAM_NO_ZEROMAP:
 	case I915_CONTEXT_PARAM_BAN_PERIOD:
+	case I915_CONTEXT_PARAM_ENGINES:
 	case I915_CONTEXT_PARAM_RINGSIZE:
 	default:
 		ret = -EINVAL;
-- 
2.38.1