1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2019 Intel Corporation
4  */
5 
6 #include "intel_memory_region.h"
7 #include "i915_gem_region.h"
8 #include "i915_drv.h"
9 #include "i915_trace.h"
10 
i915_gem_object_init_memory_region(struct drm_i915_gem_object * obj,struct intel_memory_region * mem)11 void i915_gem_object_init_memory_region(struct drm_i915_gem_object *obj,
12 					struct intel_memory_region *mem)
13 {
14 	obj->mm.region = intel_memory_region_get(mem);
15 
16 	mutex_lock(&mem->objects.lock);
17 	list_add(&obj->mm.region_link, &mem->objects.list);
18 	mutex_unlock(&mem->objects.lock);
19 }
20 
i915_gem_object_release_memory_region(struct drm_i915_gem_object * obj)21 void i915_gem_object_release_memory_region(struct drm_i915_gem_object *obj)
22 {
23 	struct intel_memory_region *mem = obj->mm.region;
24 
25 	mutex_lock(&mem->objects.lock);
26 	list_del(&obj->mm.region_link);
27 	mutex_unlock(&mem->objects.lock);
28 
29 	intel_memory_region_put(mem);
30 }
31 
32 struct drm_i915_gem_object *
i915_gem_object_create_region(struct intel_memory_region * mem,resource_size_t size,resource_size_t page_size,unsigned int flags)33 i915_gem_object_create_region(struct intel_memory_region *mem,
34 			      resource_size_t size,
35 			      resource_size_t page_size,
36 			      unsigned int flags)
37 {
38 	struct drm_i915_gem_object *obj;
39 	resource_size_t default_page_size;
40 	int err;
41 
42 	/*
43 	 * NB: Our use of resource_size_t for the size stems from using struct
44 	 * resource for the mem->region. We might need to revisit this in the
45 	 * future.
46 	 */
47 
48 	GEM_BUG_ON(flags & ~I915_BO_ALLOC_FLAGS);
49 
50 	if (!mem)
51 		return ERR_PTR(-ENODEV);
52 
53 	default_page_size = mem->min_page_size;
54 	if (page_size)
55 		default_page_size = page_size;
56 
57 	GEM_BUG_ON(!is_power_of_2_u64(default_page_size));
58 	GEM_BUG_ON(default_page_size < PAGE_SIZE);
59 
60 	size = round_up(size, default_page_size);
61 
62 	GEM_BUG_ON(!size);
63 	GEM_BUG_ON(!IS_ALIGNED(size, I915_GTT_MIN_ALIGNMENT));
64 
65 	if (i915_gem_object_size_2big(size))
66 		return ERR_PTR(-E2BIG);
67 
68 	obj = i915_gem_object_alloc();
69 	if (!obj)
70 		return ERR_PTR(-ENOMEM);
71 
72 	err = mem->ops->init_object(mem, obj, size, page_size, flags);
73 	if (err)
74 		goto err_object_free;
75 
76 	trace_i915_gem_object_create(obj);
77 	return obj;
78 
79 err_object_free:
80 	i915_gem_object_free(obj);
81 	return ERR_PTR(err);
82 }
83 
84 /**
85  * i915_gem_process_region - Iterate over all objects of a region using ops
86  * to process and optionally skip objects
87  * @mr: The memory region
88  * @apply: ops and private data
89  *
90  * This function can be used to iterate over the regions object list,
91  * checking whether to skip objects, and, if not, lock the objects and
92  * process them using the supplied ops. Note that this function temporarily
93  * removes objects from the region list while iterating, so that if run
94  * concurrently with itself may not iterate over all objects.
95  *
96  * Return: 0 if successful, negative error code on failure.
97  */
i915_gem_process_region(struct intel_memory_region * mr,struct i915_gem_apply_to_region * apply)98 int i915_gem_process_region(struct intel_memory_region *mr,
99 			    struct i915_gem_apply_to_region *apply)
100 {
101 	const struct i915_gem_apply_to_region_ops *ops = apply->ops;
102 	struct drm_i915_gem_object *obj;
103 	struct list_head still_in_list;
104 	int ret = 0;
105 
106 	/*
107 	 * In the future, a non-NULL apply->ww could mean the caller is
108 	 * already in a locking transaction and provides its own context.
109 	 */
110 	GEM_WARN_ON(apply->ww);
111 
112 	INIT_LIST_HEAD(&still_in_list);
113 	mutex_lock(&mr->objects.lock);
114 	for (;;) {
115 		struct i915_gem_ww_ctx ww;
116 
117 		obj = list_first_entry_or_null(&mr->objects.list, typeof(*obj),
118 					       mm.region_link);
119 		if (!obj)
120 			break;
121 
122 		list_move_tail(&obj->mm.region_link, &still_in_list);
123 		if (!kref_get_unless_zero(&obj->base.refcount))
124 			continue;
125 
126 		/*
127 		 * Note: Someone else might be migrating the object at this
128 		 * point. The object's region is not stable until we lock
129 		 * the object.
130 		 */
131 		mutex_unlock(&mr->objects.lock);
132 		apply->ww = &ww;
133 		for_i915_gem_ww(&ww, ret, apply->interruptible) {
134 			ret = i915_gem_object_lock(obj, apply->ww);
135 			if (ret)
136 				continue;
137 
138 			if (obj->mm.region == mr)
139 				ret = ops->process_obj(apply, obj);
140 			/* Implicit object unlock */
141 		}
142 
143 		i915_gem_object_put(obj);
144 		mutex_lock(&mr->objects.lock);
145 		if (ret)
146 			break;
147 	}
148 	list_splice_tail(&still_in_list, &mr->objects.list);
149 	mutex_unlock(&mr->objects.lock);
150 
151 	return ret;
152 }
153