1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
2 /*
3  * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved.
4  * Copyright (c) 2015 System Fabric Works, Inc. All rights reserved.
5  */
6 
7 #include "rxe.h"
8 
9 #define RXE_POOL_ALIGN		(16)
10 
11 static const struct rxe_type_info {
12 	const char *name;
13 	size_t size;
14 	size_t elem_offset;
15 	void (*cleanup)(struct rxe_pool_elem *obj);
16 	enum rxe_pool_flags flags;
17 	u32 min_index;
18 	u32 max_index;
19 } rxe_type_info[RXE_NUM_TYPES] = {
20 	[RXE_TYPE_UC] = {
21 		.name		= "rxe-uc",
22 		.size		= sizeof(struct rxe_ucontext),
23 		.elem_offset	= offsetof(struct rxe_ucontext, elem),
24 		.flags          = RXE_POOL_NO_ALLOC,
25 	},
26 	[RXE_TYPE_PD] = {
27 		.name		= "rxe-pd",
28 		.size		= sizeof(struct rxe_pd),
29 		.elem_offset	= offsetof(struct rxe_pd, elem),
30 		.flags		= RXE_POOL_NO_ALLOC,
31 	},
32 	[RXE_TYPE_AH] = {
33 		.name		= "rxe-ah",
34 		.size		= sizeof(struct rxe_ah),
35 		.elem_offset	= offsetof(struct rxe_ah, elem),
36 		.flags		= RXE_POOL_INDEX | RXE_POOL_NO_ALLOC,
37 		.min_index	= RXE_MIN_AH_INDEX,
38 		.max_index	= RXE_MAX_AH_INDEX,
39 	},
40 	[RXE_TYPE_SRQ] = {
41 		.name		= "rxe-srq",
42 		.size		= sizeof(struct rxe_srq),
43 		.elem_offset	= offsetof(struct rxe_srq, elem),
44 		.flags		= RXE_POOL_INDEX | RXE_POOL_NO_ALLOC,
45 		.min_index	= RXE_MIN_SRQ_INDEX,
46 		.max_index	= RXE_MAX_SRQ_INDEX,
47 	},
48 	[RXE_TYPE_QP] = {
49 		.name		= "rxe-qp",
50 		.size		= sizeof(struct rxe_qp),
51 		.elem_offset	= offsetof(struct rxe_qp, elem),
52 		.cleanup	= rxe_qp_cleanup,
53 		.flags		= RXE_POOL_INDEX | RXE_POOL_NO_ALLOC,
54 		.min_index	= RXE_MIN_QP_INDEX,
55 		.max_index	= RXE_MAX_QP_INDEX,
56 	},
57 	[RXE_TYPE_CQ] = {
58 		.name		= "rxe-cq",
59 		.size		= sizeof(struct rxe_cq),
60 		.elem_offset	= offsetof(struct rxe_cq, elem),
61 		.flags          = RXE_POOL_NO_ALLOC,
62 		.cleanup	= rxe_cq_cleanup,
63 	},
64 	[RXE_TYPE_MR] = {
65 		.name		= "rxe-mr",
66 		.size		= sizeof(struct rxe_mr),
67 		.elem_offset	= offsetof(struct rxe_mr, elem),
68 		.cleanup	= rxe_mr_cleanup,
69 		.flags		= RXE_POOL_INDEX,
70 		.min_index	= RXE_MIN_MR_INDEX,
71 		.max_index	= RXE_MAX_MR_INDEX,
72 	},
73 	[RXE_TYPE_MW] = {
74 		.name		= "rxe-mw",
75 		.size		= sizeof(struct rxe_mw),
76 		.elem_offset	= offsetof(struct rxe_mw, elem),
77 		.cleanup	= rxe_mw_cleanup,
78 		.flags		= RXE_POOL_INDEX | RXE_POOL_NO_ALLOC,
79 		.min_index	= RXE_MIN_MW_INDEX,
80 		.max_index	= RXE_MAX_MW_INDEX,
81 	},
82 };
83 
84 static int rxe_pool_init_index(struct rxe_pool *pool, u32 max, u32 min)
85 {
86 	int err = 0;
87 
88 	if ((max - min + 1) < pool->max_elem) {
89 		pr_warn("not enough indices for max_elem\n");
90 		err = -EINVAL;
91 		goto out;
92 	}
93 
94 	pool->index.max_index = max;
95 	pool->index.min_index = min;
96 
97 	pool->index.table = bitmap_zalloc(max - min + 1, GFP_KERNEL);
98 	if (!pool->index.table) {
99 		err = -ENOMEM;
100 		goto out;
101 	}
102 
103 out:
104 	return err;
105 }
106 
107 int rxe_pool_init(
108 	struct rxe_dev		*rxe,
109 	struct rxe_pool		*pool,
110 	enum rxe_elem_type	type,
111 	unsigned int		max_elem)
112 {
113 	const struct rxe_type_info *info = &rxe_type_info[type];
114 	int			err = 0;
115 
116 	memset(pool, 0, sizeof(*pool));
117 
118 	pool->rxe		= rxe;
119 	pool->name		= info->name;
120 	pool->type		= type;
121 	pool->max_elem		= max_elem;
122 	pool->elem_size		= ALIGN(info->size, RXE_POOL_ALIGN);
123 	pool->elem_offset	= info->elem_offset;
124 	pool->flags		= info->flags;
125 	pool->cleanup		= info->cleanup;
126 
127 	atomic_set(&pool->num_elem, 0);
128 
129 	rwlock_init(&pool->pool_lock);
130 
131 	if (pool->flags & RXE_POOL_INDEX) {
132 		pool->index.tree = RB_ROOT;
133 		err = rxe_pool_init_index(pool, info->max_index,
134 					  info->min_index);
135 		if (err)
136 			goto out;
137 	}
138 
139 out:
140 	return err;
141 }
142 
143 void rxe_pool_cleanup(struct rxe_pool *pool)
144 {
145 	if (atomic_read(&pool->num_elem) > 0)
146 		pr_warn("%s pool destroyed with unfree'd elem\n",
147 			pool->name);
148 
149 	if (pool->flags & RXE_POOL_INDEX)
150 		bitmap_free(pool->index.table);
151 }
152 
153 static u32 alloc_index(struct rxe_pool *pool)
154 {
155 	u32 index;
156 	u32 range = pool->index.max_index - pool->index.min_index + 1;
157 
158 	index = find_next_zero_bit(pool->index.table, range, pool->index.last);
159 	if (index >= range)
160 		index = find_first_zero_bit(pool->index.table, range);
161 
162 	WARN_ON_ONCE(index >= range);
163 	set_bit(index, pool->index.table);
164 	pool->index.last = index;
165 	return index + pool->index.min_index;
166 }
167 
168 static int rxe_insert_index(struct rxe_pool *pool, struct rxe_pool_elem *new)
169 {
170 	struct rb_node **link = &pool->index.tree.rb_node;
171 	struct rb_node *parent = NULL;
172 	struct rxe_pool_elem *elem;
173 
174 	while (*link) {
175 		parent = *link;
176 		elem = rb_entry(parent, struct rxe_pool_elem, index_node);
177 
178 		if (elem->index == new->index) {
179 			pr_warn("element already exists!\n");
180 			return -EINVAL;
181 		}
182 
183 		if (elem->index > new->index)
184 			link = &(*link)->rb_left;
185 		else
186 			link = &(*link)->rb_right;
187 	}
188 
189 	rb_link_node(&new->index_node, parent, link);
190 	rb_insert_color(&new->index_node, &pool->index.tree);
191 
192 	return 0;
193 }
194 
195 int __rxe_add_index_locked(struct rxe_pool_elem *elem)
196 {
197 	struct rxe_pool *pool = elem->pool;
198 	int err;
199 
200 	elem->index = alloc_index(pool);
201 	err = rxe_insert_index(pool, elem);
202 
203 	return err;
204 }
205 
206 int __rxe_add_index(struct rxe_pool_elem *elem)
207 {
208 	struct rxe_pool *pool = elem->pool;
209 	unsigned long flags;
210 	int err;
211 
212 	write_lock_irqsave(&pool->pool_lock, flags);
213 	err = __rxe_add_index_locked(elem);
214 	write_unlock_irqrestore(&pool->pool_lock, flags);
215 
216 	return err;
217 }
218 
219 void __rxe_drop_index_locked(struct rxe_pool_elem *elem)
220 {
221 	struct rxe_pool *pool = elem->pool;
222 
223 	clear_bit(elem->index - pool->index.min_index, pool->index.table);
224 	rb_erase(&elem->index_node, &pool->index.tree);
225 }
226 
227 void __rxe_drop_index(struct rxe_pool_elem *elem)
228 {
229 	struct rxe_pool *pool = elem->pool;
230 	unsigned long flags;
231 
232 	write_lock_irqsave(&pool->pool_lock, flags);
233 	__rxe_drop_index_locked(elem);
234 	write_unlock_irqrestore(&pool->pool_lock, flags);
235 }
236 
237 void *rxe_alloc_locked(struct rxe_pool *pool)
238 {
239 	struct rxe_pool_elem *elem;
240 	void *obj;
241 
242 	if (atomic_inc_return(&pool->num_elem) > pool->max_elem)
243 		goto out_cnt;
244 
245 	obj = kzalloc(pool->elem_size, GFP_ATOMIC);
246 	if (!obj)
247 		goto out_cnt;
248 
249 	elem = (struct rxe_pool_elem *)((u8 *)obj + pool->elem_offset);
250 
251 	elem->pool = pool;
252 	elem->obj = obj;
253 	kref_init(&elem->ref_cnt);
254 
255 	return obj;
256 
257 out_cnt:
258 	atomic_dec(&pool->num_elem);
259 	return NULL;
260 }
261 
262 void *rxe_alloc(struct rxe_pool *pool)
263 {
264 	struct rxe_pool_elem *elem;
265 	void *obj;
266 
267 	if (atomic_inc_return(&pool->num_elem) > pool->max_elem)
268 		goto out_cnt;
269 
270 	obj = kzalloc(pool->elem_size, GFP_KERNEL);
271 	if (!obj)
272 		goto out_cnt;
273 
274 	elem = (struct rxe_pool_elem *)((u8 *)obj + pool->elem_offset);
275 
276 	elem->pool = pool;
277 	elem->obj = obj;
278 	kref_init(&elem->ref_cnt);
279 
280 	return obj;
281 
282 out_cnt:
283 	atomic_dec(&pool->num_elem);
284 	return NULL;
285 }
286 
287 int __rxe_add_to_pool(struct rxe_pool *pool, struct rxe_pool_elem *elem)
288 {
289 	if (atomic_inc_return(&pool->num_elem) > pool->max_elem)
290 		goto out_cnt;
291 
292 	elem->pool = pool;
293 	elem->obj = (u8 *)elem - pool->elem_offset;
294 	kref_init(&elem->ref_cnt);
295 
296 	return 0;
297 
298 out_cnt:
299 	atomic_dec(&pool->num_elem);
300 	return -EINVAL;
301 }
302 
303 void rxe_elem_release(struct kref *kref)
304 {
305 	struct rxe_pool_elem *elem =
306 		container_of(kref, struct rxe_pool_elem, ref_cnt);
307 	struct rxe_pool *pool = elem->pool;
308 	void *obj;
309 
310 	if (pool->cleanup)
311 		pool->cleanup(elem);
312 
313 	if (!(pool->flags & RXE_POOL_NO_ALLOC)) {
314 		obj = elem->obj;
315 		kfree(obj);
316 	}
317 
318 	atomic_dec(&pool->num_elem);
319 }
320 
321 void *rxe_pool_get_index_locked(struct rxe_pool *pool, u32 index)
322 {
323 	struct rb_node *node;
324 	struct rxe_pool_elem *elem;
325 	void *obj;
326 
327 	node = pool->index.tree.rb_node;
328 
329 	while (node) {
330 		elem = rb_entry(node, struct rxe_pool_elem, index_node);
331 
332 		if (elem->index > index)
333 			node = node->rb_left;
334 		else if (elem->index < index)
335 			node = node->rb_right;
336 		else
337 			break;
338 	}
339 
340 	if (node) {
341 		kref_get(&elem->ref_cnt);
342 		obj = elem->obj;
343 	} else {
344 		obj = NULL;
345 	}
346 
347 	return obj;
348 }
349 
350 void *rxe_pool_get_index(struct rxe_pool *pool, u32 index)
351 {
352 	unsigned long flags;
353 	void *obj;
354 
355 	read_lock_irqsave(&pool->pool_lock, flags);
356 	obj = rxe_pool_get_index_locked(pool, index);
357 	read_unlock_irqrestore(&pool->pool_lock, flags);
358 
359 	return obj;
360 }
361