1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /*
3  * Huge page-table-entry support for IO memory.
4  *
5  * Copyright (C) 2007-2019 Vmware, Inc. All rights reservedd.
6  */
7 #include "vmwgfx_drv.h"
8 #include <drm/ttm/ttm_module.h>
9 #include <drm/ttm/ttm_bo_driver.h>
10 #include <drm/ttm/ttm_placement.h>
11 
12 /**
13  * struct vmw_thp_manager - Range manager implementing huge page alignment
14  *
15  * @mm: The underlying range manager. Protected by @lock.
16  * @lock: Manager lock.
17  */
18 struct vmw_thp_manager {
19 	struct ttm_resource_manager manager;
20 	struct drm_mm mm;
21 	spinlock_t lock;
22 };
23 
to_thp_manager(struct ttm_resource_manager * man)24 static struct vmw_thp_manager *to_thp_manager(struct ttm_resource_manager *man)
25 {
26 	return container_of(man, struct vmw_thp_manager, manager);
27 }
28 
29 static const struct ttm_resource_manager_func vmw_thp_func;
30 
vmw_thp_insert_aligned(struct drm_mm * mm,struct drm_mm_node * node,unsigned long align_pages,const struct ttm_place * place,struct ttm_resource * mem,unsigned long lpfn,enum drm_mm_insert_mode mode)31 static int vmw_thp_insert_aligned(struct drm_mm *mm, struct drm_mm_node *node,
32 				  unsigned long align_pages,
33 				  const struct ttm_place *place,
34 				  struct ttm_resource *mem,
35 				  unsigned long lpfn,
36 				  enum drm_mm_insert_mode mode)
37 {
38 	if (align_pages >= mem->page_alignment &&
39 	    (!mem->page_alignment || align_pages % mem->page_alignment == 0)) {
40 		return drm_mm_insert_node_in_range(mm, node,
41 						   mem->num_pages,
42 						   align_pages, 0,
43 						   place->fpfn, lpfn, mode);
44 	}
45 
46 	return -ENOSPC;
47 }
48 
vmw_thp_get_node(struct ttm_resource_manager * man,struct ttm_buffer_object * bo,const struct ttm_place * place,struct ttm_resource * mem)49 static int vmw_thp_get_node(struct ttm_resource_manager *man,
50 			    struct ttm_buffer_object *bo,
51 			    const struct ttm_place *place,
52 			    struct ttm_resource *mem)
53 {
54 	struct vmw_thp_manager *rman = to_thp_manager(man);
55 	struct drm_mm *mm = &rman->mm;
56 	struct drm_mm_node *node;
57 	unsigned long align_pages;
58 	unsigned long lpfn;
59 	enum drm_mm_insert_mode mode = DRM_MM_INSERT_BEST;
60 	int ret;
61 
62 	node = kzalloc(sizeof(*node), GFP_KERNEL);
63 	if (!node)
64 		return -ENOMEM;
65 
66 	lpfn = place->lpfn;
67 	if (!lpfn)
68 		lpfn = man->size;
69 
70 	mode = DRM_MM_INSERT_BEST;
71 	if (place->flags & TTM_PL_FLAG_TOPDOWN)
72 		mode = DRM_MM_INSERT_HIGH;
73 
74 	spin_lock(&rman->lock);
75 	if (IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) {
76 		align_pages = (HPAGE_PUD_SIZE >> PAGE_SHIFT);
77 		if (mem->num_pages >= align_pages) {
78 			ret = vmw_thp_insert_aligned(mm, node, align_pages,
79 						     place, mem, lpfn, mode);
80 			if (!ret)
81 				goto found_unlock;
82 		}
83 	}
84 
85 	align_pages = (HPAGE_PMD_SIZE >> PAGE_SHIFT);
86 	if (mem->num_pages >= align_pages) {
87 		ret = vmw_thp_insert_aligned(mm, node, align_pages, place, mem,
88 					     lpfn, mode);
89 		if (!ret)
90 			goto found_unlock;
91 	}
92 
93 	ret = drm_mm_insert_node_in_range(mm, node, mem->num_pages,
94 					  mem->page_alignment, 0,
95 					  place->fpfn, lpfn, mode);
96 found_unlock:
97 	spin_unlock(&rman->lock);
98 
99 	if (unlikely(ret)) {
100 		kfree(node);
101 	} else {
102 		mem->mm_node = node;
103 		mem->start = node->start;
104 	}
105 
106 	return ret;
107 }
108 
109 
110 
vmw_thp_put_node(struct ttm_resource_manager * man,struct ttm_resource * mem)111 static void vmw_thp_put_node(struct ttm_resource_manager *man,
112 			     struct ttm_resource *mem)
113 {
114 	struct vmw_thp_manager *rman = to_thp_manager(man);
115 
116 	if (mem->mm_node) {
117 		spin_lock(&rman->lock);
118 		drm_mm_remove_node(mem->mm_node);
119 		spin_unlock(&rman->lock);
120 
121 		kfree(mem->mm_node);
122 		mem->mm_node = NULL;
123 	}
124 }
125 
vmw_thp_init(struct vmw_private * dev_priv)126 int vmw_thp_init(struct vmw_private *dev_priv)
127 {
128 	struct vmw_thp_manager *rman;
129 
130 	rman = kzalloc(sizeof(*rman), GFP_KERNEL);
131 	if (!rman)
132 		return -ENOMEM;
133 
134 	ttm_resource_manager_init(&rman->manager,
135 				  dev_priv->vram_size >> PAGE_SHIFT);
136 
137 	rman->manager.func = &vmw_thp_func;
138 	drm_mm_init(&rman->mm, 0, rman->manager.size);
139 	spin_lock_init(&rman->lock);
140 
141 	ttm_set_driver_manager(&dev_priv->bdev, TTM_PL_VRAM, &rman->manager);
142 	ttm_resource_manager_set_used(&rman->manager, true);
143 	return 0;
144 }
145 
vmw_thp_fini(struct vmw_private * dev_priv)146 void vmw_thp_fini(struct vmw_private *dev_priv)
147 {
148 	struct ttm_resource_manager *man = ttm_manager_type(&dev_priv->bdev, TTM_PL_VRAM);
149 	struct vmw_thp_manager *rman = to_thp_manager(man);
150 	struct drm_mm *mm = &rman->mm;
151 	int ret;
152 
153 	ttm_resource_manager_set_used(man, false);
154 
155 	ret = ttm_resource_manager_force_list_clean(&dev_priv->bdev, man);
156 	if (ret)
157 		return;
158 	spin_lock(&rman->lock);
159 	drm_mm_clean(mm);
160 	drm_mm_takedown(mm);
161 	spin_unlock(&rman->lock);
162 	ttm_resource_manager_cleanup(man);
163 	ttm_set_driver_manager(&dev_priv->bdev, TTM_PL_VRAM, NULL);
164 	kfree(rman);
165 }
166 
vmw_thp_debug(struct ttm_resource_manager * man,struct drm_printer * printer)167 static void vmw_thp_debug(struct ttm_resource_manager *man,
168 			  struct drm_printer *printer)
169 {
170 	struct vmw_thp_manager *rman = to_thp_manager(man);
171 
172 	spin_lock(&rman->lock);
173 	drm_mm_print(&rman->mm, printer);
174 	spin_unlock(&rman->lock);
175 }
176 
177 static const struct ttm_resource_manager_func vmw_thp_func = {
178 	.alloc = vmw_thp_get_node,
179 	.free = vmw_thp_put_node,
180 	.debug = vmw_thp_debug
181 };
182