1 /*
2  * Copyright 2012 Red Hat Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: Ben Skeggs
23  */
24 #include <core/mm.h>
25 
26 #define node(root, dir) ((root)->nl_entry.dir == &mm->nodes) ? NULL :          \
27 	list_entry((root)->nl_entry.dir, struct nvkm_mm_node, nl_entry)
28 
29 void
nvkm_mm_dump(struct nvkm_mm * mm,const char * header)30 nvkm_mm_dump(struct nvkm_mm *mm, const char *header)
31 {
32 	struct nvkm_mm_node *node;
33 
34 	pr_err("nvkm: %s\n", header);
35 	pr_err("nvkm: node list:\n");
36 	list_for_each_entry(node, &mm->nodes, nl_entry) {
37 		pr_err("nvkm: \t%08x %08x %d\n",
38 		       node->offset, node->length, node->type);
39 	}
40 	pr_err("nvkm: free list:\n");
41 	list_for_each_entry(node, &mm->free, fl_entry) {
42 		pr_err("nvkm: \t%08x %08x %d\n",
43 		       node->offset, node->length, node->type);
44 	}
45 }
46 
47 void
nvkm_mm_free(struct nvkm_mm * mm,struct nvkm_mm_node ** pthis)48 nvkm_mm_free(struct nvkm_mm *mm, struct nvkm_mm_node **pthis)
49 {
50 	struct nvkm_mm_node *this = *pthis;
51 
52 	if (this) {
53 		struct nvkm_mm_node *prev = node(this, prev);
54 		struct nvkm_mm_node *next = node(this, next);
55 
56 		if (prev && prev->type == NVKM_MM_TYPE_NONE) {
57 			prev->length += this->length;
58 			list_del(&this->nl_entry);
59 			kfree(this); this = prev;
60 		}
61 
62 		if (next && next->type == NVKM_MM_TYPE_NONE) {
63 			next->offset  = this->offset;
64 			next->length += this->length;
65 			if (this->type == NVKM_MM_TYPE_NONE)
66 				list_del(&this->fl_entry);
67 			list_del(&this->nl_entry);
68 			kfree(this); this = NULL;
69 		}
70 
71 		if (this && this->type != NVKM_MM_TYPE_NONE) {
72 			list_for_each_entry(prev, &mm->free, fl_entry) {
73 				if (this->offset < prev->offset)
74 					break;
75 			}
76 
77 			list_add_tail(&this->fl_entry, &prev->fl_entry);
78 			this->type = NVKM_MM_TYPE_NONE;
79 		}
80 	}
81 
82 	*pthis = NULL;
83 }
84 
85 static struct nvkm_mm_node *
region_head(struct nvkm_mm * mm,struct nvkm_mm_node * a,u32 size)86 region_head(struct nvkm_mm *mm, struct nvkm_mm_node *a, u32 size)
87 {
88 	struct nvkm_mm_node *b;
89 
90 	if (a->length == size)
91 		return a;
92 
93 	b = kmalloc(sizeof(*b), GFP_KERNEL);
94 	if (unlikely(b == NULL))
95 		return NULL;
96 
97 	b->offset = a->offset;
98 	b->length = size;
99 	b->heap   = a->heap;
100 	b->type   = a->type;
101 	a->offset += size;
102 	a->length -= size;
103 	list_add_tail(&b->nl_entry, &a->nl_entry);
104 	if (b->type == NVKM_MM_TYPE_NONE)
105 		list_add_tail(&b->fl_entry, &a->fl_entry);
106 
107 	return b;
108 }
109 
110 int
nvkm_mm_head(struct nvkm_mm * mm,u8 heap,u8 type,u32 size_max,u32 size_min,u32 align,struct nvkm_mm_node ** pnode)111 nvkm_mm_head(struct nvkm_mm *mm, u8 heap, u8 type, u32 size_max, u32 size_min,
112 	     u32 align, struct nvkm_mm_node **pnode)
113 {
114 	struct nvkm_mm_node *prev, *this, *next;
115 	u32 mask = align - 1;
116 	u32 splitoff;
117 	u32 s, e;
118 
119 	BUG_ON(type == NVKM_MM_TYPE_NONE || type == NVKM_MM_TYPE_HOLE);
120 
121 	list_for_each_entry(this, &mm->free, fl_entry) {
122 		if (unlikely(heap != NVKM_MM_HEAP_ANY)) {
123 			if (this->heap != heap)
124 				continue;
125 		}
126 		e = this->offset + this->length;
127 		s = this->offset;
128 
129 		prev = node(this, prev);
130 		if (prev && prev->type != type)
131 			s = roundup(s, mm->block_size);
132 
133 		next = node(this, next);
134 		if (next && next->type != type)
135 			e = rounddown(e, mm->block_size);
136 
137 		s  = (s + mask) & ~mask;
138 		e &= ~mask;
139 		if (s > e || e - s < size_min)
140 			continue;
141 
142 		splitoff = s - this->offset;
143 		if (splitoff && !region_head(mm, this, splitoff))
144 			return -ENOMEM;
145 
146 		this = region_head(mm, this, min(size_max, e - s));
147 		if (!this)
148 			return -ENOMEM;
149 
150 		this->next = NULL;
151 		this->type = type;
152 		list_del(&this->fl_entry);
153 		*pnode = this;
154 		return 0;
155 	}
156 
157 	return -ENOSPC;
158 }
159 
160 static struct nvkm_mm_node *
region_tail(struct nvkm_mm * mm,struct nvkm_mm_node * a,u32 size)161 region_tail(struct nvkm_mm *mm, struct nvkm_mm_node *a, u32 size)
162 {
163 	struct nvkm_mm_node *b;
164 
165 	if (a->length == size)
166 		return a;
167 
168 	b = kmalloc(sizeof(*b), GFP_KERNEL);
169 	if (unlikely(b == NULL))
170 		return NULL;
171 
172 	a->length -= size;
173 	b->offset  = a->offset + a->length;
174 	b->length  = size;
175 	b->heap    = a->heap;
176 	b->type    = a->type;
177 
178 	list_add(&b->nl_entry, &a->nl_entry);
179 	if (b->type == NVKM_MM_TYPE_NONE)
180 		list_add(&b->fl_entry, &a->fl_entry);
181 
182 	return b;
183 }
184 
185 int
nvkm_mm_tail(struct nvkm_mm * mm,u8 heap,u8 type,u32 size_max,u32 size_min,u32 align,struct nvkm_mm_node ** pnode)186 nvkm_mm_tail(struct nvkm_mm *mm, u8 heap, u8 type, u32 size_max, u32 size_min,
187 	     u32 align, struct nvkm_mm_node **pnode)
188 {
189 	struct nvkm_mm_node *prev, *this, *next;
190 	u32 mask = align - 1;
191 
192 	BUG_ON(type == NVKM_MM_TYPE_NONE || type == NVKM_MM_TYPE_HOLE);
193 
194 	list_for_each_entry_reverse(this, &mm->free, fl_entry) {
195 		u32 e = this->offset + this->length;
196 		u32 s = this->offset;
197 		u32 c = 0, a;
198 		if (unlikely(heap != NVKM_MM_HEAP_ANY)) {
199 			if (this->heap != heap)
200 				continue;
201 		}
202 
203 		prev = node(this, prev);
204 		if (prev && prev->type != type)
205 			s = roundup(s, mm->block_size);
206 
207 		next = node(this, next);
208 		if (next && next->type != type) {
209 			e = rounddown(e, mm->block_size);
210 			c = next->offset - e;
211 		}
212 
213 		s = (s + mask) & ~mask;
214 		a = e - s;
215 		if (s > e || a < size_min)
216 			continue;
217 
218 		a  = min(a, size_max);
219 		s  = (e - a) & ~mask;
220 		c += (e - s) - a;
221 
222 		if (c && !region_tail(mm, this, c))
223 			return -ENOMEM;
224 
225 		this = region_tail(mm, this, a);
226 		if (!this)
227 			return -ENOMEM;
228 
229 		this->next = NULL;
230 		this->type = type;
231 		list_del(&this->fl_entry);
232 		*pnode = this;
233 		return 0;
234 	}
235 
236 	return -ENOSPC;
237 }
238 
239 int
nvkm_mm_init(struct nvkm_mm * mm,u8 heap,u32 offset,u32 length,u32 block)240 nvkm_mm_init(struct nvkm_mm *mm, u8 heap, u32 offset, u32 length, u32 block)
241 {
242 	struct nvkm_mm_node *node, *prev;
243 	u32 next;
244 
245 	if (nvkm_mm_initialised(mm)) {
246 		prev = list_last_entry(&mm->nodes, typeof(*node), nl_entry);
247 		next = prev->offset + prev->length;
248 		if (next != offset) {
249 			BUG_ON(next > offset);
250 			if (!(node = kzalloc(sizeof(*node), GFP_KERNEL)))
251 				return -ENOMEM;
252 			node->type   = NVKM_MM_TYPE_HOLE;
253 			node->offset = next;
254 			node->length = offset - next;
255 			list_add_tail(&node->nl_entry, &mm->nodes);
256 		}
257 		BUG_ON(block != mm->block_size);
258 	} else {
259 		INIT_LIST_HEAD(&mm->nodes);
260 		INIT_LIST_HEAD(&mm->free);
261 		mm->block_size = block;
262 		mm->heap_nodes = 0;
263 	}
264 
265 	node = kzalloc(sizeof(*node), GFP_KERNEL);
266 	if (!node)
267 		return -ENOMEM;
268 
269 	if (length) {
270 		node->offset  = roundup(offset, mm->block_size);
271 		node->length  = rounddown(offset + length, mm->block_size);
272 		node->length -= node->offset;
273 	}
274 
275 	list_add_tail(&node->nl_entry, &mm->nodes);
276 	list_add_tail(&node->fl_entry, &mm->free);
277 	node->heap = heap;
278 	mm->heap_nodes++;
279 	return 0;
280 }
281 
282 int
nvkm_mm_fini(struct nvkm_mm * mm)283 nvkm_mm_fini(struct nvkm_mm *mm)
284 {
285 	struct nvkm_mm_node *node, *temp;
286 	int nodes = 0;
287 
288 	if (!nvkm_mm_initialised(mm))
289 		return 0;
290 
291 	list_for_each_entry(node, &mm->nodes, nl_entry) {
292 		if (node->type != NVKM_MM_TYPE_HOLE) {
293 			if (++nodes > mm->heap_nodes) {
294 				nvkm_mm_dump(mm, "mm not clean!");
295 				return -EBUSY;
296 			}
297 		}
298 	}
299 
300 	list_for_each_entry_safe(node, temp, &mm->nodes, nl_entry) {
301 		list_del(&node->nl_entry);
302 		kfree(node);
303 	}
304 
305 	mm->heap_nodes = 0;
306 	return 0;
307 }
308