kernel/bpf/arraymap.c

   1 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
   2  * Copyright (c) 2016,2017 Facebook
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of version 2 of the GNU General Public
   6  * License as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11  * General Public License for more details.
  12  */
  13 #include <linux/bpf.h>
  14 #include <linux/err.h>
  15 #include <linux/slab.h>
  16 #include <linux/mm.h>
  17 #include <linux/filter.h>
  18 #include <linux/perf_event.h>
  19
  20 #include "map_in_map.h"
  21
  22 #define ARRAY_CREATE_FLAG_MASK \
  23         (BPF_F_NUMA_NODE | BPF_F_RDONLY | BPF_F_WRONLY)
  24
  25 static void bpf_array_free_percpu(struct bpf_array *array)
  26 {
  27         int i;
  28
  29         for (i = 0; i < array->map.max_entries; i++)
  30                 free_percpu(array->pptrs[i]);
  31 }
  32
  33 static int bpf_array_alloc_percpu(struct bpf_array *array)
  34 {
  35         void __percpu *ptr;
  36         int i;
  37
  38         for (i = 0; i < array->map.max_entries; i++) {
  39                 ptr = __alloc_percpu_gfp(array->elem_size, 8,
  40                                          GFP_USER | __GFP_NOWARN);
  41                 if (!ptr) {
  42                         bpf_array_free_percpu(array);
  43                         return -ENOMEM;
  44                 }
  45                 array->pptrs[i] = ptr;
  46         }
  47
  48         return 0;
  49 }
  50
  51 /* Called from syscall */
  52 static struct bpf_map *array_map_alloc(union bpf_attr *attr)
  53 {
  54         bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY;
  55         int numa_node = bpf_map_attr_numa_node(attr);
  56         struct bpf_array *array;
  57         u64 array_size;
  58         u32 elem_size;
  59
  60         /* check sanity of attributes */
  61         if (attr->max_entries == 0 || attr->key_size != 4 ||
  62             attr->value_size == 0 ||
  63             attr->map_flags & ~ARRAY_CREATE_FLAG_MASK ||
  64             (percpu && numa_node != NUMA_NO_NODE))
  65                 return ERR_PTR(-EINVAL);
  66
  67         if (attr->value_size > KMALLOC_MAX_SIZE)
  68                 /* if value_size is bigger, the user space won't be able to
  69                  * access the elements.
  70                  */
  71                 return ERR_PTR(-E2BIG);
  72
  73         elem_size = round_up(attr->value_size, 8);
  74
  75         array_size = sizeof(*array);
  76         if (percpu)
  77                 array_size += (u64) attr->max_entries * sizeof(void *);
  78         else
  79                 array_size += (u64) attr->max_entries * elem_size;
  80
  81         /* make sure there is no u32 overflow later in round_up() */
  82         if (array_size >= U32_MAX - PAGE_SIZE)
  83                 return ERR_PTR(-ENOMEM);
  84
  85         /* allocate all map elements and zero-initialize them */
  86         array = bpf_map_area_alloc(array_size, numa_node);
  87         if (!array)
  88                 return ERR_PTR(-ENOMEM);
  89
  90         /* copy mandatory map attributes */
  91         array->map.map_type = attr->map_type;
  92         array->map.key_size = attr->key_size;
  93         array->map.value_size = attr->value_size;
  94         array->map.max_entries = attr->max_entries;
  95         array->map.map_flags = attr->map_flags;
  96         array->map.numa_node = numa_node;
  97         array->elem_size = elem_size;
  98
  99         if (!percpu)
 100                 goto out;
 101
 102         array_size += (u64) attr->max_entries * elem_size * num_possible_cpus();
 103
 104         if (array_size >= U32_MAX - PAGE_SIZE ||
 105             bpf_array_alloc_percpu(array)) {
 106                 bpf_map_area_free(array);
 107                 return ERR_PTR(-ENOMEM);
 108         }
 109 out:
 110         array->map.pages = round_up(array_size, PAGE_SIZE) >> PAGE_SHIFT;
 111
 112         return &array->map;
 113 }
 114
 115 /* Called from syscall or from eBPF program */
 116 static void *array_map_lookup_elem(struct bpf_map *map, void *key)
 117 {
 118         struct bpf_array *array = container_of(map, struct bpf_array, map);
 119         u32 index = *(u32 *)key;
 120
 121         if (unlikely(index >= array->map.max_entries))
 122                 return NULL;
 123
 124         return array->value + array->elem_size * index;
 125 }
 126
 127 /* emit BPF instructions equivalent to C code of array_map_lookup_elem() */
 128 static u32 array_map_gen_lookup(struct bpf_map *map, struct bpf_insn *insn_buf)
 129 {
 130         struct bpf_insn *insn = insn_buf;
 131         u32 elem_size = round_up(map->value_size, 8);
 132         const int ret = BPF_REG_0;
 133         const int map_ptr = BPF_REG_1;
 134         const int index = BPF_REG_2;
 135
 136         *insn++ = BPF_ALU64_IMM(BPF_ADD, map_ptr, offsetof(struct bpf_array, value));
 137         *insn++ = BPF_LDX_MEM(BPF_W, ret, index, 0);
 138         *insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 3);
 139
 140         if (is_power_of_2(elem_size)) {
 141                 *insn++ = BPF_ALU64_IMM(BPF_LSH, ret, ilog2(elem_size));
 142         } else {
 143                 *insn++ = BPF_ALU64_IMM(BPF_MUL, ret, elem_size);
 144         }
 145         *insn++ = BPF_ALU64_REG(BPF_ADD, ret, map_ptr);
 146         *insn++ = BPF_JMP_IMM(BPF_JA, 0, 0, 1);
 147         *insn++ = BPF_MOV64_IMM(ret, 0);
 148         return insn - insn_buf;
 149 }
 150
 151 /* Called from eBPF program */
 152 static void *percpu_array_map_lookup_elem(struct bpf_map *map, void *key)
 153 {
 154         struct bpf_array *array = container_of(map, struct bpf_array, map);
 155         u32 index = *(u32 *)key;
 156
 157         if (unlikely(index >= array->map.max_entries))
 158                 return NULL;
 159
 160         return this_cpu_ptr(array->pptrs[index]);
 161 }
 162
 163 int bpf_percpu_array_copy(struct bpf_map *map, void *key, void *value)
 164 {
 165         struct bpf_array *array = container_of(map, struct bpf_array, map);
 166         u32 index = *(u32 *)key;
 167         void __percpu *pptr;
 168         int cpu, off = 0;
 169         u32 size;
 170
 171         if (unlikely(index >= array->map.max_entries))
 172                 return -ENOENT;
 173
 174         /* per_cpu areas are zero-filled and bpf programs can only
 175          * access 'value_size' of them, so copying rounded areas
 176          * will not leak any kernel data
 177          */
 178         size = round_up(map->value_size, 8);
 179         rcu_read_lock();
 180         pptr = array->pptrs[index];
 181         for_each_possible_cpu(cpu) {
 182                 bpf_long_memcpy(value + off, per_cpu_ptr(pptr, cpu), size);
 183                 off += size;
 184         }
 185         rcu_read_unlock();
 186         return 0;
 187 }
 188
 189 /* Called from syscall */
 190 static int array_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
 191 {
 192         struct bpf_array *array = container_of(map, struct bpf_array, map);
 193         u32 index = key ? *(u32 *)key : U32_MAX;
 194         u32 *next = (u32 *)next_key;
 195
 196         if (index >= array->map.max_entries) {
 197                 *next = 0;
 198                 return 0;
 199         }
 200
 201         if (index == array->map.max_entries - 1)
 202                 return -ENOENT;
 203
 204         *next = index + 1;
 205         return 0;
 206 }
 207
 208 /* Called from syscall or from eBPF program */
 209 static int array_map_update_elem(struct bpf_map *map, void *key, void *value,
 210                                  u64 map_flags)
 211 {
 212         struct bpf_array *array = container_of(map, struct bpf_array, map);
 213         u32 index = *(u32 *)key;
 214
 215         if (unlikely(map_flags > BPF_EXIST))
 216                 /* unknown flags */
 217                 return -EINVAL;
 218
 219         if (unlikely(index >= array->map.max_entries))
 220                 /* all elements were pre-allocated, cannot insert a new one */
 221                 return -E2BIG;
 222
 223         if (unlikely(map_flags == BPF_NOEXIST))
 224                 /* all elements already exist */
 225                 return -EEXIST;
 226
 227         if (array->map.map_type == BPF_MAP_TYPE_PERCPU_ARRAY)
 228                 memcpy(this_cpu_ptr(array->pptrs[index]),
 229                        value, map->value_size);
 230         else
 231                 memcpy(array->value + array->elem_size * index,
 232                        value, map->value_size);
 233         return 0;
 234 }
 235
 236 int bpf_percpu_array_update(struct bpf_map *map, void *key, void *value,
 237                             u64 map_flags)
 238 {
 239         struct bpf_array *array = container_of(map, struct bpf_array, map);
 240         u32 index = *(u32 *)key;
 241         void __percpu *pptr;
 242         int cpu, off = 0;
 243         u32 size;
 244
 245         if (unlikely(map_flags > BPF_EXIST))
 246                 /* unknown flags */
 247                 return -EINVAL;
 248
 249         if (unlikely(index >= array->map.max_entries))
 250                 /* all elements were pre-allocated, cannot insert a new one */
 251                 return -E2BIG;
 252
 253         if (unlikely(map_flags == BPF_NOEXIST))
 254                 /* all elements already exist */
 255                 return -EEXIST;
 256
 257         /* the user space will provide round_up(value_size, 8) bytes that
 258          * will be copied into per-cpu area. bpf programs can only access
 259          * value_size of it. During lookup the same extra bytes will be
 260          * returned or zeros which were zero-filled by percpu_alloc,
 261          * so no kernel data leaks possible
 262          */
 263         size = round_up(map->value_size, 8);
 264         rcu_read_lock();
 265         pptr = array->pptrs[index];
 266         for_each_possible_cpu(cpu) {
 267                 bpf_long_memcpy(per_cpu_ptr(pptr, cpu), value + off, size);
 268                 off += size;
 269         }
 270         rcu_read_unlock();
 271         return 0;
 272 }
 273
 274 /* Called from syscall or from eBPF program */
 275 static int array_map_delete_elem(struct bpf_map *map, void *key)
 276 {
 277         return -EINVAL;
 278 }
 279
 280 /* Called when map->refcnt goes to zero, either from workqueue or from syscall */
 281 static void array_map_free(struct bpf_map *map)
 282 {
 283         struct bpf_array *array = container_of(map, struct bpf_array, map);
 284
 285         /* at this point bpf_prog->aux->refcnt == 0 and this map->refcnt == 0,
 286          * so the programs (can be more than one that used this map) were
 287          * disconnected from events. Wait for outstanding programs to complete
 288          * and free the array
 289          */
 290         synchronize_rcu();
 291
 292         if (array->map.map_type == BPF_MAP_TYPE_PERCPU_ARRAY)
 293                 bpf_array_free_percpu(array);
 294
 295         bpf_map_area_free(array);
 296 }
 297
 298 const struct bpf_map_ops array_map_ops = {
 299         .map_alloc = array_map_alloc,
 300         .map_free = array_map_free,
 301         .map_get_next_key = array_map_get_next_key,
 302         .map_lookup_elem = array_map_lookup_elem,
 303         .map_update_elem = array_map_update_elem,
 304         .map_delete_elem = array_map_delete_elem,
 305         .map_gen_lookup = array_map_gen_lookup,
 306 };
 307
 308 const struct bpf_map_ops percpu_array_map_ops = {
 309         .map_alloc = array_map_alloc,
 310         .map_free = array_map_free,
 311         .map_get_next_key = array_map_get_next_key,
 312         .map_lookup_elem = percpu_array_map_lookup_elem,
 313         .map_update_elem = array_map_update_elem,
 314         .map_delete_elem = array_map_delete_elem,
 315 };
 316
 317 static struct bpf_map *fd_array_map_alloc(union bpf_attr *attr)
 318 {
 319         /* only file descriptors can be stored in this type of map */
 320         if (attr->value_size != sizeof(u32))
 321                 return ERR_PTR(-EINVAL);
 322         return array_map_alloc(attr);
 323 }
 324
 325 static void fd_array_map_free(struct bpf_map *map)
 326 {
 327         struct bpf_array *array = container_of(map, struct bpf_array, map);
 328         int i;
 329
 330         synchronize_rcu();
 331
 332         /* make sure it's empty */
 333         for (i = 0; i < array->map.max_entries; i++)
 334                 BUG_ON(array->ptrs[i] != NULL);
 335
 336         bpf_map_area_free(array);
 337 }
 338
 339 static void *fd_array_map_lookup_elem(struct bpf_map *map, void *key)
 340 {
 341         return NULL;
 342 }
 343
 344 /* only called from syscall */
 345 int bpf_fd_array_map_lookup_elem(struct bpf_map *map, void *key, u32 *value)
 346 {
 347         void **elem, *ptr;
 348         int ret =  0;
 349
 350         if (!map->ops->map_fd_sys_lookup_elem)
 351                 return -ENOTSUPP;
 352
 353         rcu_read_lock();
 354         elem = array_map_lookup_elem(map, key);
 355         if (elem && (ptr = READ_ONCE(*elem)))
 356                 *value = map->ops->map_fd_sys_lookup_elem(ptr);
 357         else
 358                 ret = -ENOENT;
 359         rcu_read_unlock();
 360
 361         return ret;
 362 }
 363
 364 /* only called from syscall */
 365 int bpf_fd_array_map_update_elem(struct bpf_map *map, struct file *map_file,
 366                                  void *key, void *value, u64 map_flags)
 367 {
 368         struct bpf_array *array = container_of(map, struct bpf_array, map);
 369         void *new_ptr, *old_ptr;
 370         u32 index = *(u32 *)key, ufd;
 371
 372         if (map_flags != BPF_ANY)
 373                 return -EINVAL;
 374
 375         if (index >= array->map.max_entries)
 376                 return -E2BIG;
 377
 378         ufd = *(u32 *)value;
 379         new_ptr = map->ops->map_fd_get_ptr(map, map_file, ufd);
 380         if (IS_ERR(new_ptr))
 381                 return PTR_ERR(new_ptr);
 382
 383         old_ptr = xchg(array->ptrs + index, new_ptr);
 384         if (old_ptr)
 385                 map->ops->map_fd_put_ptr(old_ptr);
 386
 387         return 0;
 388 }
 389
 390 static int fd_array_map_delete_elem(struct bpf_map *map, void *key)
 391 {
 392         struct bpf_array *array = container_of(map, struct bpf_array, map);
 393         void *old_ptr;
 394         u32 index = *(u32 *)key;
 395
 396         if (index >= array->map.max_entries)
 397                 return -E2BIG;
 398
 399         old_ptr = xchg(array->ptrs + index, NULL);
 400         if (old_ptr) {
 401                 map->ops->map_fd_put_ptr(old_ptr);
 402                 return 0;
 403         } else {
 404                 return -ENOENT;
 405         }
 406 }
 407
 408 static void *prog_fd_array_get_ptr(struct bpf_map *map,
 409                                    struct file *map_file, int fd)
 410 {
 411         struct bpf_array *array = container_of(map, struct bpf_array, map);
 412         struct bpf_prog *prog = bpf_prog_get(fd);
 413
 414         if (IS_ERR(prog))
 415                 return prog;
 416
 417         if (!bpf_prog_array_compatible(array, prog)) {
 418                 bpf_prog_put(prog);
 419                 return ERR_PTR(-EINVAL);
 420         }
 421
 422         return prog;
 423 }
 424
 425 static void prog_fd_array_put_ptr(void *ptr)
 426 {
 427         bpf_prog_put(ptr);
 428 }
 429
 430 static u32 prog_fd_array_sys_lookup_elem(void *ptr)
 431 {
 432         return ((struct bpf_prog *)ptr)->aux->id;
 433 }
 434
 435 /* decrement refcnt of all bpf_progs that are stored in this map */
 436 void bpf_fd_array_map_clear(struct bpf_map *map)
 437 {
 438         struct bpf_array *array = container_of(map, struct bpf_array, map);
 439         int i;
 440
 441         for (i = 0; i < array->map.max_entries; i++)
 442                 fd_array_map_delete_elem(map, &i);
 443 }
 444
 445 const struct bpf_map_ops prog_array_map_ops = {
 446         .map_alloc = fd_array_map_alloc,
 447         .map_free = fd_array_map_free,
 448         .map_get_next_key = array_map_get_next_key,
 449         .map_lookup_elem = fd_array_map_lookup_elem,
 450         .map_delete_elem = fd_array_map_delete_elem,
 451         .map_fd_get_ptr = prog_fd_array_get_ptr,
 452         .map_fd_put_ptr = prog_fd_array_put_ptr,
 453         .map_fd_sys_lookup_elem = prog_fd_array_sys_lookup_elem,
 454 };
 455
 456 static struct bpf_event_entry *bpf_event_entry_gen(struct file *perf_file,
 457                                                    struct file *map_file)
 458 {
 459         struct bpf_event_entry *ee;
 460
 461         ee = kzalloc(sizeof(*ee), GFP_ATOMIC);
 462         if (ee) {
 463                 ee->event = perf_file->private_data;
 464                 ee->perf_file = perf_file;
 465                 ee->map_file = map_file;
 466         }
 467
 468         return ee;
 469 }
 470
 471 static void __bpf_event_entry_free(struct rcu_head *rcu)
 472 {
 473         struct bpf_event_entry *ee;
 474
 475         ee = container_of(rcu, struct bpf_event_entry, rcu);
 476         fput(ee->perf_file);
 477         kfree(ee);
 478 }
 479
 480 static void bpf_event_entry_free_rcu(struct bpf_event_entry *ee)
 481 {
 482         call_rcu(&ee->rcu, __bpf_event_entry_free);
 483 }
 484
 485 static void *perf_event_fd_array_get_ptr(struct bpf_map *map,
 486                                          struct file *map_file, int fd)
 487 {
 488         struct bpf_event_entry *ee;
 489         struct perf_event *event;
 490         struct file *perf_file;
 491         u64 value;
 492
 493         perf_file = perf_event_get(fd);
 494         if (IS_ERR(perf_file))
 495                 return perf_file;
 496
 497         ee = ERR_PTR(-EOPNOTSUPP);
 498         event = perf_file->private_data;
 499         if (perf_event_read_local(event, &value, NULL, NULL) == -EOPNOTSUPP)
 500                 goto err_out;
 501
 502         ee = bpf_event_entry_gen(perf_file, map_file);
 503         if (ee)
 504                 return ee;
 505         ee = ERR_PTR(-ENOMEM);
 506 err_out:
 507         fput(perf_file);
 508         return ee;
 509 }
 510
 511 static void perf_event_fd_array_put_ptr(void *ptr)
 512 {
 513         bpf_event_entry_free_rcu(ptr);
 514 }
 515
 516 static void perf_event_fd_array_release(struct bpf_map *map,
 517                                         struct file *map_file)
 518 {
 519         struct bpf_array *array = container_of(map, struct bpf_array, map);
 520         struct bpf_event_entry *ee;
 521         int i;
 522
 523         rcu_read_lock();
 524         for (i = 0; i < array->map.max_entries; i++) {
 525                 ee = READ_ONCE(array->ptrs[i]);
 526                 if (ee && ee->map_file == map_file)
 527                         fd_array_map_delete_elem(map, &i);
 528         }
 529         rcu_read_unlock();
 530 }
 531
 532 const struct bpf_map_ops perf_event_array_map_ops = {
 533         .map_alloc = fd_array_map_alloc,
 534         .map_free = fd_array_map_free,
 535         .map_get_next_key = array_map_get_next_key,
 536         .map_lookup_elem = fd_array_map_lookup_elem,
 537         .map_delete_elem = fd_array_map_delete_elem,
 538         .map_fd_get_ptr = perf_event_fd_array_get_ptr,
 539         .map_fd_put_ptr = perf_event_fd_array_put_ptr,
 540         .map_release = perf_event_fd_array_release,
 541 };
 542
 543 #ifdef CONFIG_CGROUPS
 544 static void *cgroup_fd_array_get_ptr(struct bpf_map *map,
 545                                      struct file *map_file /* not used */,
 546                                      int fd)
 547 {
 548         return cgroup_get_from_fd(fd);
 549 }
 550
 551 static void cgroup_fd_array_put_ptr(void *ptr)
 552 {
 553         /* cgroup_put free cgrp after a rcu grace period */
 554         cgroup_put(ptr);
 555 }
 556
 557 static void cgroup_fd_array_free(struct bpf_map *map)
 558 {
 559         bpf_fd_array_map_clear(map);
 560         fd_array_map_free(map);
 561 }
 562
 563 const struct bpf_map_ops cgroup_array_map_ops = {
 564         .map_alloc = fd_array_map_alloc,
 565         .map_free = cgroup_fd_array_free,
 566         .map_get_next_key = array_map_get_next_key,
 567         .map_lookup_elem = fd_array_map_lookup_elem,
 568         .map_delete_elem = fd_array_map_delete_elem,
 569         .map_fd_get_ptr = cgroup_fd_array_get_ptr,
 570         .map_fd_put_ptr = cgroup_fd_array_put_ptr,
 571 };
 572 #endif
 573
 574 static struct bpf_map *array_of_map_alloc(union bpf_attr *attr)
 575 {
 576         struct bpf_map *map, *inner_map_meta;
 577
 578         inner_map_meta = bpf_map_meta_alloc(attr->inner_map_fd);
 579         if (IS_ERR(inner_map_meta))
 580                 return inner_map_meta;
 581
 582         map = fd_array_map_alloc(attr);
 583         if (IS_ERR(map)) {
 584                 bpf_map_meta_free(inner_map_meta);
 585                 return map;
 586         }
 587
 588         map->inner_map_meta = inner_map_meta;
 589
 590         return map;
 591 }
 592
 593 static void array_of_map_free(struct bpf_map *map)
 594 {
 595         /* map->inner_map_meta is only accessed by syscall which
 596          * is protected by fdget/fdput.
 597          */
 598         bpf_map_meta_free(map->inner_map_meta);
 599         bpf_fd_array_map_clear(map);
 600         fd_array_map_free(map);
 601 }
 602
 603 static void *array_of_map_lookup_elem(struct bpf_map *map, void *key)
 604 {
 605         struct bpf_map **inner_map = array_map_lookup_elem(map, key);
 606
 607         if (!inner_map)
 608                 return NULL;
 609
 610         return READ_ONCE(*inner_map);
 611 }
 612
 613 static u32 array_of_map_gen_lookup(struct bpf_map *map,
 614                                    struct bpf_insn *insn_buf)
 615 {
 616         u32 elem_size = round_up(map->value_size, 8);
 617         struct bpf_insn *insn = insn_buf;
 618         const int ret = BPF_REG_0;
 619         const int map_ptr = BPF_REG_1;
 620         const int index = BPF_REG_2;
 621
 622         *insn++ = BPF_ALU64_IMM(BPF_ADD, map_ptr, offsetof(struct bpf_array, value));
 623         *insn++ = BPF_LDX_MEM(BPF_W, ret, index, 0);
 624         *insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 5);
 625         if (is_power_of_2(elem_size))
 626                 *insn++ = BPF_ALU64_IMM(BPF_LSH, ret, ilog2(elem_size));
 627         else
 628                 *insn++ = BPF_ALU64_IMM(BPF_MUL, ret, elem_size);
 629         *insn++ = BPF_ALU64_REG(BPF_ADD, ret, map_ptr);
 630         *insn++ = BPF_LDX_MEM(BPF_DW, ret, ret, 0);
 631         *insn++ = BPF_JMP_IMM(BPF_JEQ, ret, 0, 1);
 632         *insn++ = BPF_JMP_IMM(BPF_JA, 0, 0, 1);
 633         *insn++ = BPF_MOV64_IMM(ret, 0);
 634
 635         return insn - insn_buf;
 636 }
 637
 638 const struct bpf_map_ops array_of_maps_map_ops = {
 639         .map_alloc = array_of_map_alloc,
 640         .map_free = array_of_map_free,
 641         .map_get_next_key = array_map_get_next_key,
 642         .map_lookup_elem = array_of_map_lookup_elem,
 643         .map_delete_elem = fd_array_map_delete_elem,
 644         .map_fd_get_ptr = bpf_map_fd_get_ptr,
 645         .map_fd_put_ptr = bpf_map_fd_put_ptr,
 646         .map_fd_sys_lookup_elem = bpf_map_fd_sys_lookup_elem,
 647         .map_gen_lookup = array_of_map_gen_lookup,
 648 };