lib/librte_vhost/iotlb.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright (c) 2017 Red Hat, Inc.
   3  */
   4
   5 #ifdef RTE_LIBRTE_VHOST_NUMA
   6 #include <numaif.h>
   7 #endif
   8
   9 #include <rte_tailq.h>
  10
  11 #include "iotlb.h"
  12 #include "vhost.h"
  13
  14 struct vhost_iotlb_entry {
  15         TAILQ_ENTRY(vhost_iotlb_entry) next;
  16
  17         uint64_t iova;
  18         uint64_t uaddr;
  19         uint64_t size;
  20         uint8_t perm;
  21 };
  22
  23 #define IOTLB_CACHE_SIZE 2048
  24
  25 static void
  26 vhost_user_iotlb_cache_random_evict(struct vhost_virtqueue *vq);
  27
  28 static void
  29 vhost_user_iotlb_pending_remove_all(struct vhost_virtqueue *vq)
  30 {
  31         struct vhost_iotlb_entry *node, *temp_node;
  32
  33         rte_rwlock_write_lock(&vq->iotlb_pending_lock);
  34
  35         TAILQ_FOREACH_SAFE(node, &vq->iotlb_pending_list, next, temp_node) {
  36                 TAILQ_REMOVE(&vq->iotlb_pending_list, node, next);
  37                 rte_mempool_put(vq->iotlb_pool, node);
  38         }
  39
  40         rte_rwlock_write_unlock(&vq->iotlb_pending_lock);
  41 }
  42
  43 bool
  44 vhost_user_iotlb_pending_miss(struct vhost_virtqueue *vq, uint64_t iova,
  45                                 uint8_t perm)
  46 {
  47         struct vhost_iotlb_entry *node;
  48         bool found = false;
  49
  50         rte_rwlock_read_lock(&vq->iotlb_pending_lock);
  51
  52         TAILQ_FOREACH(node, &vq->iotlb_pending_list, next) {
  53                 if ((node->iova == iova) && (node->perm == perm)) {
  54                         found = true;
  55                         break;
  56                 }
  57         }
  58
  59         rte_rwlock_read_unlock(&vq->iotlb_pending_lock);
  60
  61         return found;
  62 }
  63
  64 void
  65 vhost_user_iotlb_pending_insert(struct vhost_virtqueue *vq,
  66                                 uint64_t iova, uint8_t perm)
  67 {
  68         struct vhost_iotlb_entry *node;
  69         int ret;
  70
  71         ret = rte_mempool_get(vq->iotlb_pool, (void **)&node);
  72         if (ret) {
  73                 VHOST_LOG_CONFIG(DEBUG, "IOTLB pool empty, clear entries\n");
  74                 if (!TAILQ_EMPTY(&vq->iotlb_pending_list))
  75                         vhost_user_iotlb_pending_remove_all(vq);
  76                 else
  77                         vhost_user_iotlb_cache_random_evict(vq);
  78                 ret = rte_mempool_get(vq->iotlb_pool, (void **)&node);
  79                 if (ret) {
  80                         VHOST_LOG_CONFIG(ERR, "IOTLB pool still empty, failure\n");
  81                         return;
  82                 }
  83         }
  84
  85         node->iova = iova;
  86         node->perm = perm;
  87
  88         rte_rwlock_write_lock(&vq->iotlb_pending_lock);
  89
  90         TAILQ_INSERT_TAIL(&vq->iotlb_pending_list, node, next);
  91
  92         rte_rwlock_write_unlock(&vq->iotlb_pending_lock);
  93 }
  94
  95 void
  96 vhost_user_iotlb_pending_remove(struct vhost_virtqueue *vq,
  97                                 uint64_t iova, uint64_t size, uint8_t perm)
  98 {
  99         struct vhost_iotlb_entry *node, *temp_node;
 100
 101         rte_rwlock_write_lock(&vq->iotlb_pending_lock);
 102
 103         TAILQ_FOREACH_SAFE(node, &vq->iotlb_pending_list, next, temp_node) {
 104                 if (node->iova < iova)
 105                         continue;
 106                 if (node->iova >= iova + size)
 107                         continue;
 108                 if ((node->perm & perm) != node->perm)
 109                         continue;
 110                 TAILQ_REMOVE(&vq->iotlb_pending_list, node, next);
 111                 rte_mempool_put(vq->iotlb_pool, node);
 112         }
 113
 114         rte_rwlock_write_unlock(&vq->iotlb_pending_lock);
 115 }
 116
 117 static void
 118 vhost_user_iotlb_cache_remove_all(struct vhost_virtqueue *vq)
 119 {
 120         struct vhost_iotlb_entry *node, *temp_node;
 121
 122         rte_rwlock_write_lock(&vq->iotlb_lock);
 123
 124         TAILQ_FOREACH_SAFE(node, &vq->iotlb_list, next, temp_node) {
 125                 TAILQ_REMOVE(&vq->iotlb_list, node, next);
 126                 rte_mempool_put(vq->iotlb_pool, node);
 127         }
 128
 129         vq->iotlb_cache_nr = 0;
 130
 131         rte_rwlock_write_unlock(&vq->iotlb_lock);
 132 }
 133
 134 static void
 135 vhost_user_iotlb_cache_random_evict(struct vhost_virtqueue *vq)
 136 {
 137         struct vhost_iotlb_entry *node, *temp_node;
 138         int entry_idx;
 139
 140         rte_rwlock_write_lock(&vq->iotlb_lock);
 141
 142         entry_idx = rte_rand() % vq->iotlb_cache_nr;
 143
 144         TAILQ_FOREACH_SAFE(node, &vq->iotlb_list, next, temp_node) {
 145                 if (!entry_idx) {
 146                         TAILQ_REMOVE(&vq->iotlb_list, node, next);
 147                         rte_mempool_put(vq->iotlb_pool, node);
 148                         vq->iotlb_cache_nr--;
 149                         break;
 150                 }
 151                 entry_idx--;
 152         }
 153
 154         rte_rwlock_write_unlock(&vq->iotlb_lock);
 155 }
 156
 157 void
 158 vhost_user_iotlb_cache_insert(struct vhost_virtqueue *vq, uint64_t iova,
 159                                 uint64_t uaddr, uint64_t size, uint8_t perm)
 160 {
 161         struct vhost_iotlb_entry *node, *new_node;
 162         int ret;
 163
 164         ret = rte_mempool_get(vq->iotlb_pool, (void **)&new_node);
 165         if (ret) {
 166                 VHOST_LOG_CONFIG(DEBUG, "IOTLB pool empty, clear entries\n");
 167                 if (!TAILQ_EMPTY(&vq->iotlb_list))
 168                         vhost_user_iotlb_cache_random_evict(vq);
 169                 else
 170                         vhost_user_iotlb_pending_remove_all(vq);
 171                 ret = rte_mempool_get(vq->iotlb_pool, (void **)&new_node);
 172                 if (ret) {
 173                         VHOST_LOG_CONFIG(ERR, "IOTLB pool still empty, failure\n");
 174                         return;
 175                 }
 176         }
 177
 178         new_node->iova = iova;
 179         new_node->uaddr = uaddr;
 180         new_node->size = size;
 181         new_node->perm = perm;
 182
 183         rte_rwlock_write_lock(&vq->iotlb_lock);
 184
 185         TAILQ_FOREACH(node, &vq->iotlb_list, next) {
 186                 /*
 187                  * Entries must be invalidated before being updated.
 188                  * So if iova already in list, assume identical.
 189                  */
 190                 if (node->iova == new_node->iova) {
 191                         rte_mempool_put(vq->iotlb_pool, new_node);
 192                         goto unlock;
 193                 } else if (node->iova > new_node->iova) {
 194                         TAILQ_INSERT_BEFORE(node, new_node, next);
 195                         vq->iotlb_cache_nr++;
 196                         goto unlock;
 197                 }
 198         }
 199
 200         TAILQ_INSERT_TAIL(&vq->iotlb_list, new_node, next);
 201         vq->iotlb_cache_nr++;
 202
 203 unlock:
 204         vhost_user_iotlb_pending_remove(vq, iova, size, perm);
 205
 206         rte_rwlock_write_unlock(&vq->iotlb_lock);
 207
 208 }
 209
 210 void
 211 vhost_user_iotlb_cache_remove(struct vhost_virtqueue *vq,
 212                                         uint64_t iova, uint64_t size)
 213 {
 214         struct vhost_iotlb_entry *node, *temp_node;
 215
 216         if (unlikely(!size))
 217                 return;
 218
 219         rte_rwlock_write_lock(&vq->iotlb_lock);
 220
 221         TAILQ_FOREACH_SAFE(node, &vq->iotlb_list, next, temp_node) {
 222                 /* Sorted list */
 223                 if (unlikely(iova + size < node->iova))
 224                         break;
 225
 226                 if (iova < node->iova + node->size) {
 227                         TAILQ_REMOVE(&vq->iotlb_list, node, next);
 228                         rte_mempool_put(vq->iotlb_pool, node);
 229                         vq->iotlb_cache_nr--;
 230                 }
 231         }
 232
 233         rte_rwlock_write_unlock(&vq->iotlb_lock);
 234 }
 235
 236 uint64_t
 237 vhost_user_iotlb_cache_find(struct vhost_virtqueue *vq, uint64_t iova,
 238                                                 uint64_t *size, uint8_t perm)
 239 {
 240         struct vhost_iotlb_entry *node;
 241         uint64_t offset, vva = 0, mapped = 0;
 242
 243         if (unlikely(!*size))
 244                 goto out;
 245
 246         TAILQ_FOREACH(node, &vq->iotlb_list, next) {
 247                 /* List sorted by iova */
 248                 if (unlikely(iova < node->iova))
 249                         break;
 250
 251                 if (iova >= node->iova + node->size)
 252                         continue;
 253
 254                 if (unlikely((perm & node->perm) != perm)) {
 255                         vva = 0;
 256                         break;
 257                 }
 258
 259                 offset = iova - node->iova;
 260                 if (!vva)
 261                         vva = node->uaddr + offset;
 262
 263                 mapped += node->size - offset;
 264                 iova = node->iova + node->size;
 265
 266                 if (mapped >= *size)
 267                         break;
 268         }
 269
 270 out:
 271         /* Only part of the requested chunk is mapped */
 272         if (unlikely(mapped < *size))
 273                 *size = mapped;
 274
 275         return vva;
 276 }
 277
 278 void
 279 vhost_user_iotlb_flush_all(struct vhost_virtqueue *vq)
 280 {
 281         vhost_user_iotlb_cache_remove_all(vq);
 282         vhost_user_iotlb_pending_remove_all(vq);
 283 }
 284
 285 int
 286 vhost_user_iotlb_init(struct virtio_net *dev, int vq_index)
 287 {
 288         char pool_name[RTE_MEMPOOL_NAMESIZE];
 289         struct vhost_virtqueue *vq = dev->virtqueue[vq_index];
 290         int socket = 0;
 291
 292         if (vq->iotlb_pool) {
 293                 /*
 294                  * The cache has already been initialized,
 295                  * just drop all cached and pending entries.
 296                  */
 297                 vhost_user_iotlb_flush_all(vq);
 298         }
 299
 300 #ifdef RTE_LIBRTE_VHOST_NUMA
 301         if (get_mempolicy(&socket, NULL, 0, vq, MPOL_F_NODE | MPOL_F_ADDR) != 0)
 302                 socket = 0;
 303 #endif
 304
 305         rte_rwlock_init(&vq->iotlb_lock);
 306         rte_rwlock_init(&vq->iotlb_pending_lock);
 307
 308         TAILQ_INIT(&vq->iotlb_list);
 309         TAILQ_INIT(&vq->iotlb_pending_list);
 310
 311         snprintf(pool_name, sizeof(pool_name), "iotlb_%u_%d_%d",
 312                         getpid(), dev->vid, vq_index);
 313         VHOST_LOG_CONFIG(DEBUG, "IOTLB cache name: %s\n", pool_name);
 314
 315         /* If already created, free it and recreate */
 316         vq->iotlb_pool = rte_mempool_lookup(pool_name);
 317         if (vq->iotlb_pool)
 318                 rte_mempool_free(vq->iotlb_pool);
 319
 320         vq->iotlb_pool = rte_mempool_create(pool_name,
 321                         IOTLB_CACHE_SIZE, sizeof(struct vhost_iotlb_entry), 0,
 322                         0, 0, NULL, NULL, NULL, socket,
 323                         MEMPOOL_F_NO_CACHE_ALIGN |
 324                         MEMPOOL_F_SP_PUT |
 325                         MEMPOOL_F_SC_GET);
 326         if (!vq->iotlb_pool) {
 327                 VHOST_LOG_CONFIG(ERR,
 328                                 "Failed to create IOTLB cache pool (%s)\n",
 329                                 pool_name);
 330                 return -1;
 331         }
 332
 333         vq->iotlb_cache_nr = 0;
 334
 335         return 0;
 336 }