summaryrefslogtreecommitdiffstats
path: root/drivers/net/mlx4/mlx4_mr.c
blob: 2a3e2695b40f7a9d4fe3f4e40ea3a1ab5e28e244 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
/*-
 *   BSD LICENSE
 *
 *   Copyright 2017 6WIND S.A.
 *   Copyright 2017 Mellanox
 *
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
 *     * Neither the name of 6WIND S.A. nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/**
 * @file
 * Memory management functions for mlx4 driver.
 */

#include <assert.h>
#include <errno.h>
#include <inttypes.h>
#include <stddef.h>
#include <stdint.h>
#include <string.h>

/* Verbs headers do not support -pedantic. */
#ifdef PEDANTIC
#pragma GCC diagnostic ignored "-Wpedantic"
#endif
#include <infiniband/verbs.h>
#ifdef PEDANTIC
#pragma GCC diagnostic error "-Wpedantic"
#endif

#include <rte_branch_prediction.h>
#include <rte_common.h>
#include <rte_errno.h>
#include <rte_malloc.h>
#include <rte_memory.h>
#include <rte_mempool.h>
#include <rte_spinlock.h>

#include "mlx4_rxtx.h"
#include "mlx4_utils.h"

struct mlx4_check_mempool_data {
	int ret;
	char *start;
	char *end;
};

/**
 * Called by mlx4_check_mempool() when iterating the memory chunks.
 *
 * @param[in] mp
 *   Pointer to memory pool (unused).
 * @param[in, out] data
 *   Pointer to shared buffer with mlx4_check_mempool().
 * @param[in] memhdr
 *   Pointer to mempool chunk header.
 * @param mem_idx
 *   Mempool element index (unused).
 */
static void
mlx4_check_mempool_cb(struct rte_mempool *mp, void *opaque,
		      struct rte_mempool_memhdr *memhdr,
		      unsigned int mem_idx)
{
	struct mlx4_check_mempool_data *data = opaque;

	(void)mp;
	(void)mem_idx;
	/* It already failed, skip the next chunks. */
	if (data->ret != 0)
		return;
	/* It is the first chunk. */
	if (data->start == NULL && data->end == NULL) {
		data->start = memhdr->addr;
		data->end = data->start + memhdr->len;
		return;
	}
	if (data->end == memhdr->addr) {
		data->end += memhdr->len;
		return;
	}
	if (data->start == (char *)memhdr->addr + memhdr->len) {
		data->start -= memhdr->len;
		return;
	}
	/* Error, mempool is not virtually contiguous. */
	data->ret = -1;
}

/**
 * Check if a mempool can be used: it must be virtually contiguous.
 *
 * @param[in] mp
 *   Pointer to memory pool.
 * @param[out] start
 *   Pointer to the start address of the mempool virtual memory area.
 * @param[out] end
 *   Pointer to the end address of the mempool virtual memory area.
 *
 * @return
 *   0 on success (mempool is virtually contiguous), -1 on error.
 */
static int
mlx4_check_mempool(struct rte_mempool *mp, uintptr_t *start, uintptr_t *end)
{
	struct mlx4_check_mempool_data data;

	memset(&data, 0, sizeof(data));
	rte_mempool_mem_iter(mp, mlx4_check_mempool_cb, &data);
	*start = (uintptr_t)data.start;
	*end = (uintptr_t)data.end;
	return data.ret;
}

/**
 * Obtain a memory region from a memory pool.
 *
 * If a matching memory region already exists, it is returned with its
 * reference count incremented, otherwise a new one is registered.
 *
 * @param priv
 *   Pointer to private structure.
 * @param mp
 *   Pointer to memory pool.
 *
 * @return
 *   Memory region pointer, NULL in case of error and rte_errno is set.
 */
struct mlx4_mr *
mlx4_mr_get(struct priv *priv, struct rte_mempool *mp)
{
	const struct rte_memseg *ms = rte_eal_get_physmem_layout();
	uintptr_t start;
	uintptr_t end;
	unsigned int i;
	struct mlx4_mr *mr;

	if (mlx4_check_mempool(mp, &start, &end) != 0) {
		rte_errno = EINVAL;
		ERROR("mempool %p: not virtually contiguous",
			(void *)mp);
		return NULL;
	}
	DEBUG("mempool %p area start=%p end=%p size=%zu",
	      (void *)mp, (void *)start, (void *)end,
	      (size_t)(end - start));
	/* Round start and end to page boundary if found in memory segments. */
	for (i = 0; (i < RTE_MAX_MEMSEG) && (ms[i].addr != NULL); ++i) {
		uintptr_t addr = (uintptr_t)ms[i].addr;
		size_t len = ms[i].len;
		unsigned int align = ms[i].hugepage_sz;

		if ((start > addr) && (start < addr + len))
			start = RTE_ALIGN_FLOOR(start, align);
		if ((end > addr) && (end < addr + len))
			end = RTE_ALIGN_CEIL(end, align);
	}
	DEBUG("mempool %p using start=%p end=%p size=%zu for MR",
	      (void *)mp, (void *)start, (void *)end,
	      (size_t)(end - start));
	rte_spinlock_lock(&priv->mr_lock);
	LIST_FOREACH(mr, &priv->mr, next)
		if (mp == mr->mp && start >= mr->start && end <= mr->end)
			break;
	if (mr) {
		++mr->refcnt;
		goto release;
	}
	mr = rte_malloc(__func__, sizeof(*mr), 0);
	if (!mr) {
		rte_errno = ENOMEM;
		goto release;
	}
	*mr = (struct mlx4_mr){
		.start = start,
		.end = end,
		.refcnt = 1,
		.priv = priv,
		.mr = ibv_reg_mr(priv->pd, (void *)start, end - start,
				 IBV_ACCESS_LOCAL_WRITE),
		.mp = mp,
	};
	if (mr->mr) {
		mr->lkey = mr->mr->lkey;
		LIST_INSERT_HEAD(&priv->mr, mr, next);
	} else {
		rte_free(mr);
		mr = NULL;
		rte_errno = errno ? errno : EINVAL;
	}
release:
	rte_spinlock_unlock(&priv->mr_lock);
	return mr;
}

/**
 * Release a memory region.
 *
 * This function decrements its reference count and destroys it after
 * reaching 0.
 *
 * Note to avoid race conditions given this function may be used from the
 * data plane, it's extremely important that each user holds its own
 * reference.
 *
 * @param mr
 *   Memory region to release.
 */
void
mlx4_mr_put(struct mlx4_mr *mr)
{
	struct priv *priv = mr->priv;

	rte_spinlock_lock(&priv->mr_lock);
	assert(mr->refcnt);
	if (--mr->refcnt)
		goto release;
	LIST_REMOVE(mr, next);
	claim_zero(ibv_dereg_mr(mr->mr));
	rte_free(mr);
release:
	rte_spinlock_unlock(&priv->mr_lock);
}

/**
 * Add memory region (MR) <-> memory pool (MP) association to txq->mp2mr[].
 * If mp2mr[] is full, remove an entry first.
 *
 * @param txq
 *   Pointer to Tx queue structure.
 * @param[in] mp
 *   Memory pool for which a memory region lkey must be added.
 * @param[in] i
 *   Index in memory pool (MP) where to add memory region (MR).
 *
 * @return
 *   Added mr->lkey on success, (uint32_t)-1 on failure.
 */
uint32_t
mlx4_txq_add_mr(struct txq *txq, struct rte_mempool *mp, uint32_t i)
{
	struct mlx4_mr *mr;

	/* Add a new entry, register MR first. */
	DEBUG("%p: discovered new memory pool \"%s\" (%p)",
	      (void *)txq, mp->name, (void *)mp);
	mr = mlx4_mr_get(txq->priv, mp);
	if (unlikely(mr == NULL)) {
		DEBUG("%p: unable to configure MR, mlx4_mr_get() failed",
		      (void *)txq);
		return (uint32_t)-1;
	}
	if (unlikely(i == RTE_DIM(txq->mp2mr))) {
		/* Table is full, remove oldest entry. */
		DEBUG("%p: MR <-> MP table full, dropping oldest entry.",
		      (void *)txq);
		--i;
		mlx4_mr_put(txq->mp2mr[0].mr);
		memmove(&txq->mp2mr[0], &txq->mp2mr[1],
			(sizeof(txq->mp2mr) - sizeof(txq->mp2mr[0])));
	}
	/* Store the new entry. */
	txq->mp2mr[i].mp = mp;
	txq->mp2mr[i].mr = mr;
	txq->mp2mr[i].lkey = mr->lkey;
	DEBUG("%p: new MR lkey for MP \"%s\" (%p): 0x%08" PRIu32,
	      (void *)txq, mp->name, (void *)mp, txq->mp2mr[i].lkey);
	return txq->mp2mr[i].lkey;
}