2  * SPDX-License-Identifier: MIT
4  * Copyright © 2014-2016 Intel Corporation
7 #include <linux/dma-fence-array.h>
31 	 * last_read - hence we always set both read and write busy for  in __busy_write_id()
54 	 * 1. A composite fence (dma_fence_array) constructed of i915 requests  in __busy_set_if_active()
55 	 * created during a parallel submission. In this case we deconstruct the  in __busy_set_if_active()
56 	 * composite fence into individual i915 requests and check the status of  in __busy_set_if_active()
63 		struct dma_fence **child = array->fences;  in __busy_set_if_active()
64 		unsigned int nchild = array->num_fences;  in __busy_set_if_active()
72 				      &current_fence->flags)) {  in __busy_set_if_active()
78 				return flag(rq->engine->uabi_class);  in __busy_set_if_active()
79 		} while (--nchild);  in __busy_set_if_active()
81 		/* All requests in array complete, not busy */  in __busy_set_if_active()
91 		/* Beware type-expansion follies! */  in __busy_set_if_active()
92 		BUILD_BUG_ON(!typecheck(u16, rq->engine->uabi_class));  in __busy_set_if_active()
93 		return flag(rq->engine->uabi_class);  in __busy_set_if_active()
122 	err = -ENOENT;  in i915_gem_busy_ioctl()
124 	obj = i915_gem_object_lookup_rcu(file, args->handle);  in i915_gem_busy_ioctl()
130 	 * non-i915 fences, i.e. even though we may report the object as idle,  in i915_gem_busy_ioctl()
131 	 * a call to set-domain may still stall waiting for foreign rendering.  in i915_gem_busy_ioctl()
132 	 * This also means that wait-ioctl may report an object as busy,  in i915_gem_busy_ioctl()
133 	 * where busy-ioctl considers it idle.  in i915_gem_busy_ioctl()
140 	 *	args->busy =  in i915_gem_busy_ioctl()
141 	 *		!dma_resv_test_signaled(obj->resv, DMA_RESV_USAGE_READ);  in i915_gem_busy_ioctl()
142 	 * to report the overall busyness. This is what the wait-ioctl does.  in i915_gem_busy_ioctl()
145 	args->busy = 0;  in i915_gem_busy_ioctl()
146 	dma_resv_iter_begin(&cursor, obj->base.resv, DMA_RESV_USAGE_READ);  in i915_gem_busy_ioctl()
149 			args->busy = 0;  in i915_gem_busy_ioctl()
153 			args->busy |= busy_check_writer(fence);  in i915_gem_busy_ioctl()
156 			args->busy |= busy_check_reader(fence);  in i915_gem_busy_ioctl()