xref: /dpdk/drivers/vdpa/mlx5/mlx5_vdpa_mem.c (revision 934ef2b6)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright 2019 Mellanox Technologies, Ltd
3  */
4 #include <stdlib.h>
5 
6 #include <rte_malloc.h>
7 #include <rte_errno.h>
8 #include <rte_common.h>
9 #include <rte_sched_common.h>
10 
11 #include <mlx5_prm.h>
12 #include <mlx5_common.h>
13 
14 #include "mlx5_vdpa_utils.h"
15 #include "mlx5_vdpa.h"
16 
17 void
mlx5_vdpa_mem_dereg(struct mlx5_vdpa_priv * priv)18 mlx5_vdpa_mem_dereg(struct mlx5_vdpa_priv *priv)
19 {
20 	struct mlx5_vdpa_query_mr *entry;
21 	struct mlx5_vdpa_query_mr *next;
22 
23 	entry = SLIST_FIRST(&priv->mr_list);
24 	while (entry) {
25 		next = SLIST_NEXT(entry, next);
26 		if (entry->is_indirect)
27 			claim_zero(mlx5_devx_cmd_destroy(entry->mkey));
28 		else
29 			claim_zero(mlx5_glue->dereg_mr(entry->mr));
30 		SLIST_REMOVE(&priv->mr_list, entry, mlx5_vdpa_query_mr, next);
31 		rte_free(entry);
32 		entry = next;
33 	}
34 	SLIST_INIT(&priv->mr_list);
35 	if (priv->vmem) {
36 		free(priv->vmem);
37 		priv->vmem = NULL;
38 	}
39 }
40 
41 static int
mlx5_vdpa_regions_addr_cmp(const void * a,const void * b)42 mlx5_vdpa_regions_addr_cmp(const void *a, const void *b)
43 {
44 	const struct rte_vhost_mem_region *region_a = a;
45 	const struct rte_vhost_mem_region *region_b = b;
46 
47 	if (region_a->guest_phys_addr < region_b->guest_phys_addr)
48 		return -1;
49 	if (region_a->guest_phys_addr > region_b->guest_phys_addr)
50 		return 1;
51 	return 0;
52 }
53 
54 #define KLM_NUM_MAX_ALIGN(sz) (RTE_ALIGN_CEIL(sz, MLX5_MAX_KLM_BYTE_COUNT) / \
55 			       MLX5_MAX_KLM_BYTE_COUNT)
56 
57 /*
58  * Allocate and sort the region list and choose indirect mkey mode:
59  *   1. Calculate GCD, guest memory size and indirect mkey entries num per mode.
60  *   2. Align GCD to the maximum allowed size(2G) and to be power of 2.
61  *   2. Decide the indirect mkey mode according to the next rules:
62  *         a. If both KLM_FBS entries number and KLM entries number are bigger
63  *            than the maximum allowed(MLX5_DEVX_MAX_KLM_ENTRIES) - error.
64  *         b. KLM mode if KLM_FBS entries number is bigger than the maximum
65  *            allowed(MLX5_DEVX_MAX_KLM_ENTRIES).
66  *         c. KLM mode if GCD is smaller than the minimum allowed(4K).
67  *         d. KLM mode if the total size of KLM entries is in one cache line
68  *            and the total size of KLM_FBS entries is not in one cache line.
69  *         e. Otherwise, KLM_FBS mode.
70  */
71 static struct rte_vhost_memory *
mlx5_vdpa_vhost_mem_regions_prepare(int vid,uint8_t * mode,uint64_t * mem_size,uint64_t * gcd,uint32_t * entries_num)72 mlx5_vdpa_vhost_mem_regions_prepare(int vid, uint8_t *mode, uint64_t *mem_size,
73 				    uint64_t *gcd, uint32_t *entries_num)
74 {
75 	struct rte_vhost_memory *mem;
76 	uint64_t size;
77 	uint64_t klm_entries_num = 0;
78 	uint64_t klm_fbs_entries_num;
79 	uint32_t i;
80 	int ret = rte_vhost_get_mem_table(vid, &mem);
81 
82 	if (ret < 0) {
83 		DRV_LOG(ERR, "Failed to get VM memory layout vid =%d.", vid);
84 		rte_errno = EINVAL;
85 		return NULL;
86 	}
87 	qsort(mem->regions, mem->nregions, sizeof(mem->regions[0]),
88 	      mlx5_vdpa_regions_addr_cmp);
89 	*mem_size = (mem->regions[(mem->nregions - 1)].guest_phys_addr) +
90 				      (mem->regions[(mem->nregions - 1)].size) -
91 					      (mem->regions[0].guest_phys_addr);
92 	*gcd = 0;
93 	for (i = 0; i < mem->nregions; ++i) {
94 		DRV_LOG(INFO,  "Region %u: HVA 0x%" PRIx64 ", GPA 0x%" PRIx64
95 			", size 0x%" PRIx64 ".", i,
96 			mem->regions[i].host_user_addr,
97 			mem->regions[i].guest_phys_addr, mem->regions[i].size);
98 		if (i > 0) {
99 			/* Hole handle. */
100 			size = mem->regions[i].guest_phys_addr -
101 				(mem->regions[i - 1].guest_phys_addr +
102 				 mem->regions[i - 1].size);
103 			*gcd = rte_get_gcd64(*gcd, size);
104 			klm_entries_num += KLM_NUM_MAX_ALIGN(size);
105 		}
106 		size = mem->regions[i].size;
107 		*gcd = rte_get_gcd64(*gcd, size);
108 		klm_entries_num += KLM_NUM_MAX_ALIGN(size);
109 	}
110 	if (*gcd > MLX5_MAX_KLM_BYTE_COUNT)
111 		*gcd = rte_get_gcd64(*gcd, MLX5_MAX_KLM_BYTE_COUNT);
112 	if (!RTE_IS_POWER_OF_2(*gcd)) {
113 		uint64_t candidate_gcd = rte_align64prevpow2(*gcd);
114 
115 		while (candidate_gcd > 1 && (*gcd % candidate_gcd))
116 			candidate_gcd /= 2;
117 		DRV_LOG(DEBUG, "GCD 0x%" PRIx64 " is not power of 2. Adjusted "
118 			"GCD is 0x%" PRIx64 ".", *gcd, candidate_gcd);
119 		*gcd = candidate_gcd;
120 	}
121 	klm_fbs_entries_num = *mem_size / *gcd;
122 	if (*gcd < MLX5_MIN_KLM_FIXED_BUFFER_SIZE || klm_fbs_entries_num >
123 	    MLX5_DEVX_MAX_KLM_ENTRIES ||
124 	    ((klm_entries_num * sizeof(struct mlx5_klm)) <=
125 	    RTE_CACHE_LINE_SIZE && (klm_fbs_entries_num *
126 				    sizeof(struct mlx5_klm)) >
127 							RTE_CACHE_LINE_SIZE)) {
128 		*mode = MLX5_MKC_ACCESS_MODE_KLM;
129 		*entries_num = klm_entries_num;
130 		DRV_LOG(INFO, "Indirect mkey mode is KLM.");
131 	} else {
132 		*mode = MLX5_MKC_ACCESS_MODE_KLM_FBS;
133 		*entries_num = klm_fbs_entries_num;
134 		DRV_LOG(INFO, "Indirect mkey mode is KLM Fixed Buffer Size.");
135 	}
136 	DRV_LOG(DEBUG, "Memory registration information: nregions = %u, "
137 		"mem_size = 0x%" PRIx64 ", GCD = 0x%" PRIx64
138 		", klm_fbs_entries_num = 0x%" PRIx64 ", klm_entries_num = 0x%"
139 		PRIx64 ".", mem->nregions, *mem_size, *gcd, klm_fbs_entries_num,
140 		klm_entries_num);
141 	if (*entries_num > MLX5_DEVX_MAX_KLM_ENTRIES) {
142 		DRV_LOG(ERR, "Failed to prepare memory of vid %d - memory is "
143 			"too fragmented.", vid);
144 		free(mem);
145 		return NULL;
146 	}
147 	return mem;
148 }
149 
150 static int
mlx5_vdpa_mem_cmp(struct rte_vhost_memory * mem1,struct rte_vhost_memory * mem2)151 mlx5_vdpa_mem_cmp(struct rte_vhost_memory *mem1, struct rte_vhost_memory *mem2)
152 {
153 	uint32_t i;
154 
155 	if (mem1->nregions != mem2->nregions)
156 		return -1;
157 	for (i = 0; i < mem1->nregions; i++) {
158 		if (mem1->regions[i].guest_phys_addr !=
159 		    mem2->regions[i].guest_phys_addr)
160 			return -1;
161 		if (mem1->regions[i].size != mem2->regions[i].size)
162 			return -1;
163 	}
164 	return 0;
165 }
166 
167 #define KLM_SIZE_MAX_ALIGN(sz) ((sz) > MLX5_MAX_KLM_BYTE_COUNT ? \
168 				MLX5_MAX_KLM_BYTE_COUNT : (sz))
169 
170 /*
171  * The target here is to group all the physical memory regions of the
172  * virtio device in one indirect mkey.
173  * For KLM Fixed Buffer Size mode (HW find the translation entry in one
174  * read according to the guest physical address):
175  * All the sub-direct mkeys of it must be in the same size, hence, each
176  * one of them should be in the GCD size of all the virtio memory
177  * regions and the holes between them.
178  * For KLM mode (each entry may be in different size so HW must iterate
179  * the entries):
180  * Each virtio memory region and each hole between them have one entry,
181  * just need to cover the maximum allowed size(2G) by splitting entries
182  * which their associated memory regions are bigger than 2G.
183  * It means that each virtio memory region may be mapped to more than
184  * one direct mkey in the 2 modes.
185  * All the holes of invalid memory between the virtio memory regions
186  * will be mapped to the null memory region for security.
187  */
188 int
mlx5_vdpa_mem_register(struct mlx5_vdpa_priv * priv)189 mlx5_vdpa_mem_register(struct mlx5_vdpa_priv *priv)
190 {
191 	struct mlx5_devx_mkey_attr mkey_attr;
192 	struct mlx5_vdpa_query_mr *entry = NULL;
193 	struct rte_vhost_mem_region *reg = NULL;
194 	uint8_t mode = 0;
195 	uint32_t entries_num = 0;
196 	uint32_t i;
197 	uint64_t gcd = 0;
198 	uint64_t klm_size;
199 	uint64_t mem_size;
200 	uint64_t k;
201 	int klm_index = 0;
202 	int ret;
203 	struct rte_vhost_memory *mem = mlx5_vdpa_vhost_mem_regions_prepare
204 			      (priv->vid, &mode, &mem_size, &gcd, &entries_num);
205 	struct mlx5_klm klm_array[entries_num];
206 
207 	if (!mem)
208 		return -rte_errno;
209 	if (priv->vmem != NULL) {
210 		if (mlx5_vdpa_mem_cmp(mem, priv->vmem) == 0) {
211 			/* VM memory not changed, reuse resources. */
212 			free(mem);
213 			return 0;
214 		}
215 		mlx5_vdpa_mem_dereg(priv);
216 	}
217 	priv->vmem = mem;
218 	for (i = 0; i < mem->nregions; i++) {
219 		reg = &mem->regions[i];
220 		entry = rte_zmalloc(__func__, sizeof(*entry), 0);
221 		if (!entry) {
222 			ret = -ENOMEM;
223 			DRV_LOG(ERR, "Failed to allocate mem entry memory.");
224 			goto error;
225 		}
226 		entry->mr = mlx5_glue->reg_mr_iova(priv->cdev->pd,
227 				       (void *)(uintptr_t)(reg->host_user_addr),
228 				       reg->size, reg->guest_phys_addr,
229 				       IBV_ACCESS_LOCAL_WRITE);
230 		if (!entry->mr) {
231 			DRV_LOG(ERR, "Failed to create direct Mkey.");
232 			ret = -rte_errno;
233 			goto error;
234 		}
235 		entry->is_indirect = 0;
236 		if (i > 0) {
237 			uint64_t sadd;
238 			uint64_t empty_region_sz = reg->guest_phys_addr -
239 					  (mem->regions[i - 1].guest_phys_addr +
240 					   mem->regions[i - 1].size);
241 
242 			if (empty_region_sz > 0) {
243 				sadd = mem->regions[i - 1].guest_phys_addr +
244 				       mem->regions[i - 1].size;
245 				klm_size = mode == MLX5_MKC_ACCESS_MODE_KLM ?
246 				      KLM_SIZE_MAX_ALIGN(empty_region_sz) : gcd;
247 				for (k = 0; k < empty_region_sz;
248 				     k += klm_size) {
249 					klm_array[klm_index].byte_count =
250 						k + klm_size > empty_region_sz ?
251 						 empty_region_sz - k : klm_size;
252 					klm_array[klm_index].mkey =
253 							    priv->null_mr->lkey;
254 					klm_array[klm_index].address = sadd + k;
255 					klm_index++;
256 				}
257 			}
258 		}
259 		klm_size = mode == MLX5_MKC_ACCESS_MODE_KLM ?
260 					    KLM_SIZE_MAX_ALIGN(reg->size) : gcd;
261 		for (k = 0; k < reg->size; k += klm_size) {
262 			klm_array[klm_index].byte_count = k + klm_size >
263 					   reg->size ? reg->size - k : klm_size;
264 			klm_array[klm_index].mkey = entry->mr->lkey;
265 			klm_array[klm_index].address = reg->guest_phys_addr + k;
266 			klm_index++;
267 		}
268 		SLIST_INSERT_HEAD(&priv->mr_list, entry, next);
269 	}
270 	memset(&mkey_attr, 0, sizeof(mkey_attr));
271 	mkey_attr.addr = (uintptr_t)(mem->regions[0].guest_phys_addr);
272 	mkey_attr.size = mem_size;
273 	mkey_attr.pd = priv->cdev->pdn;
274 	mkey_attr.umem_id = 0;
275 	/* Must be zero for KLM mode. */
276 	mkey_attr.log_entity_size = mode == MLX5_MKC_ACCESS_MODE_KLM_FBS ?
277 							  rte_log2_u64(gcd) : 0;
278 	mkey_attr.pg_access = 0;
279 	mkey_attr.klm_array = klm_array;
280 	mkey_attr.klm_num = klm_index;
281 	entry = rte_zmalloc(__func__, sizeof(*entry), 0);
282 	if (!entry) {
283 		DRV_LOG(ERR, "Failed to allocate memory for indirect entry.");
284 		ret = -ENOMEM;
285 		goto error;
286 	}
287 	entry->mkey = mlx5_devx_cmd_mkey_create(priv->cdev->ctx, &mkey_attr);
288 	if (!entry->mkey) {
289 		DRV_LOG(ERR, "Failed to create indirect Mkey.");
290 		ret = -rte_errno;
291 		goto error;
292 	}
293 	entry->is_indirect = 1;
294 	SLIST_INSERT_HEAD(&priv->mr_list, entry, next);
295 	priv->gpa_mkey_index = entry->mkey->id;
296 	return 0;
297 error:
298 	rte_free(entry);
299 	mlx5_vdpa_mem_dereg(priv);
300 	rte_errno = -ret;
301 	return ret;
302 }
303