sys/fs/cuse/cuse.c

   1 /* $FreeBSD$ */
   2 /*-
   3  * Copyright (c) 2010-2017 Hans Petter Selasky. All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  */
  26
  27 #include <sys/stdint.h>
  28 #include <sys/stddef.h>
  29 #include <sys/param.h>
  30 #include <sys/types.h>
  31 #include <sys/systm.h>
  32 #include <sys/conf.h>
  33 #include <sys/kernel.h>
  34 #include <sys/bus.h>
  35 #include <sys/linker_set.h>
  36 #include <sys/module.h>
  37 #include <sys/lock.h>
  38 #include <sys/mutex.h>
  39 #include <sys/condvar.h>
  40 #include <sys/sysctl.h>
  41 #include <sys/unistd.h>
  42 #include <sys/malloc.h>
  43 #include <sys/priv.h>
  44 #include <sys/uio.h>
  45 #include <sys/poll.h>
  46 #include <sys/sx.h>
  47 #include <sys/rwlock.h>
  48 #include <sys/queue.h>
  49 #include <sys/fcntl.h>
  50 #include <sys/proc.h>
  51 #include <sys/vnode.h>
  52 #include <sys/selinfo.h>
  53 #include <sys/ptrace.h>
  54 #include <sys/sysent.h>
  55
  56 #include <machine/bus.h>
  57
  58 #include <vm/vm.h>
  59 #include <vm/pmap.h>
  60 #include <vm/vm_object.h>
  61 #include <vm/vm_page.h>
  62 #include <vm/vm_pager.h>
  63
  64 #include <fs/cuse/cuse_defs.h>
  65 #include <fs/cuse/cuse_ioctl.h>
  66
  67 MODULE_VERSION(cuse, 1);
  68
  69 /*
  70  * Prevent cuse4bsd.ko and cuse.ko from loading at the same time by
  71  * declaring support for the cuse4bsd interface in cuse.ko:
  72  */
  73 MODULE_VERSION(cuse4bsd, 1);
  74
  75 #ifdef FEATURE
  76 FEATURE(cuse, "Userspace character devices");
  77 #endif
  78
  79 struct cuse_command;
  80 struct cuse_server;
  81 struct cuse_client;
  82
  83 struct cuse_client_command {
  84         TAILQ_ENTRY(cuse_client_command) entry;
  85         struct cuse_command sub;
  86         struct sx sx;
  87         struct cv cv;
  88         struct thread *entered;
  89         struct cuse_client *client;
  90         struct proc *proc_curr;
  91         int     proc_refs;
  92         int     got_signal;
  93         int     error;
  94         int     command;
  95 };
  96
  97 struct cuse_memory {
  98         TAILQ_ENTRY(cuse_memory) entry;
  99         vm_object_t object;
 100         uint32_t page_count;
 101         uint32_t alloc_nr;
 102 };
 103
 104 struct cuse_server_dev {
 105         TAILQ_ENTRY(cuse_server_dev) entry;
 106         struct cuse_server *server;
 107         struct cdev *kern_dev;
 108         struct cuse_dev *user_dev;
 109 };
 110
 111 struct cuse_server {
 112         TAILQ_ENTRY(cuse_server) entry;
 113         TAILQ_HEAD(, cuse_client_command) head;
 114         TAILQ_HEAD(, cuse_server_dev) hdev;
 115         TAILQ_HEAD(, cuse_client) hcli;
 116         TAILQ_HEAD(, cuse_memory) hmem;
 117         struct cv cv;
 118         struct selinfo selinfo;
 119         pid_t   pid;
 120         int     is_closing;
 121         int     refs;
 122 };
 123
 124 struct cuse_client {
 125         TAILQ_ENTRY(cuse_client) entry;
 126         TAILQ_ENTRY(cuse_client) entry_ref;
 127         struct cuse_client_command cmds[CUSE_CMD_MAX];
 128         struct cuse_server *server;
 129         struct cuse_server_dev *server_dev;
 130
 131         uint8_t ioctl_buffer[CUSE_BUFFER_MAX] __aligned(4);
 132
 133         int     fflags;                 /* file flags */
 134         int     cflags;                 /* client flags */
 135 #define CUSE_CLI_IS_CLOSING 0x01
 136 #define CUSE_CLI_KNOTE_NEED_READ 0x02
 137 #define CUSE_CLI_KNOTE_NEED_WRITE 0x04
 138 #define CUSE_CLI_KNOTE_HAS_READ 0x08
 139 #define CUSE_CLI_KNOTE_HAS_WRITE 0x10
 140 };
 141
 142 #define CUSE_CLIENT_CLOSING(pcc) \
 143     ((pcc)->cflags & CUSE_CLI_IS_CLOSING)
 144
 145 static  MALLOC_DEFINE(M_CUSE, "cuse", "CUSE memory");
 146
 147 static TAILQ_HEAD(, cuse_server) cuse_server_head;
 148 static struct mtx cuse_mtx;
 149 static struct cdev *cuse_dev;
 150 static struct cuse_server *cuse_alloc_unit[CUSE_DEVICES_MAX];
 151 static int cuse_alloc_unit_id[CUSE_DEVICES_MAX];
 152
 153 static void cuse_server_wakeup_all_client_locked(struct cuse_server *pcs);
 154 static void cuse_client_kqfilter_read_detach(struct knote *kn);
 155 static void cuse_client_kqfilter_write_detach(struct knote *kn);
 156 static int cuse_client_kqfilter_read_event(struct knote *kn, long hint);
 157 static int cuse_client_kqfilter_write_event(struct knote *kn, long hint);
 158
 159 static struct filterops cuse_client_kqfilter_read_ops = {
 160         .f_isfd = 1,
 161         .f_detach = cuse_client_kqfilter_read_detach,
 162         .f_event = cuse_client_kqfilter_read_event,
 163 };
 164
 165 static struct filterops cuse_client_kqfilter_write_ops = {
 166         .f_isfd = 1,
 167         .f_detach = cuse_client_kqfilter_write_detach,
 168         .f_event = cuse_client_kqfilter_write_event,
 169 };
 170
 171 static d_open_t cuse_client_open;
 172 static d_close_t cuse_client_close;
 173 static d_ioctl_t cuse_client_ioctl;
 174 static d_read_t cuse_client_read;
 175 static d_write_t cuse_client_write;
 176 static d_poll_t cuse_client_poll;
 177 static d_mmap_single_t cuse_client_mmap_single;
 178 static d_kqfilter_t cuse_client_kqfilter;
 179
 180 static struct cdevsw cuse_client_devsw = {
 181         .d_version = D_VERSION,
 182         .d_open = cuse_client_open,
 183         .d_close = cuse_client_close,
 184         .d_ioctl = cuse_client_ioctl,
 185         .d_name = "cuse_client",
 186         .d_flags = D_TRACKCLOSE,
 187         .d_read = cuse_client_read,
 188         .d_write = cuse_client_write,
 189         .d_poll = cuse_client_poll,
 190         .d_mmap_single = cuse_client_mmap_single,
 191         .d_kqfilter = cuse_client_kqfilter,
 192 };
 193
 194 static d_open_t cuse_server_open;
 195 static d_close_t cuse_server_close;
 196 static d_ioctl_t cuse_server_ioctl;
 197 static d_read_t cuse_server_read;
 198 static d_write_t cuse_server_write;
 199 static d_poll_t cuse_server_poll;
 200 static d_mmap_single_t cuse_server_mmap_single;
 201
 202 static struct cdevsw cuse_server_devsw = {
 203         .d_version = D_VERSION,
 204         .d_open = cuse_server_open,
 205         .d_close = cuse_server_close,
 206         .d_ioctl = cuse_server_ioctl,
 207         .d_name = "cuse_server",
 208         .d_flags = D_TRACKCLOSE,
 209         .d_read = cuse_server_read,
 210         .d_write = cuse_server_write,
 211         .d_poll = cuse_server_poll,
 212         .d_mmap_single = cuse_server_mmap_single,
 213 };
 214
 215 static void cuse_client_is_closing(struct cuse_client *);
 216 static int cuse_free_unit_by_id_locked(struct cuse_server *, int);
 217
 218 static void
 219 cuse_lock(void)
 220 {
 221         mtx_lock(&cuse_mtx);
 222 }
 223
 224 static void
 225 cuse_unlock(void)
 226 {
 227         mtx_unlock(&cuse_mtx);
 228 }
 229
 230 static void
 231 cuse_cmd_lock(struct cuse_client_command *pccmd)
 232 {
 233         sx_xlock(&pccmd->sx);
 234 }
 235
 236 static void
 237 cuse_cmd_unlock(struct cuse_client_command *pccmd)
 238 {
 239         sx_xunlock(&pccmd->sx);
 240 }
 241
 242 static void
 243 cuse_kern_init(void *arg)
 244 {
 245         TAILQ_INIT(&cuse_server_head);
 246
 247         mtx_init(&cuse_mtx, "cuse-mtx", NULL, MTX_DEF);
 248
 249         cuse_dev = make_dev(&cuse_server_devsw, 0,
 250             UID_ROOT, GID_OPERATOR, 0600, "cuse");
 251
 252         printf("Cuse v%d.%d.%d @ /dev/cuse\n",
 253             (CUSE_VERSION >> 16) & 0xFF, (CUSE_VERSION >> 8) & 0xFF,
 254             (CUSE_VERSION >> 0) & 0xFF);
 255 }
 256 SYSINIT(cuse_kern_init, SI_SUB_DEVFS, SI_ORDER_ANY, cuse_kern_init, NULL);
 257
 258 static void
 259 cuse_kern_uninit(void *arg)
 260 {
 261         void *ptr;
 262
 263         while (1) {
 264
 265                 printf("Cuse: Please exit all /dev/cuse instances "
 266                     "and processes which have used this device.\n");
 267
 268                 pause("DRAIN", 2 * hz);
 269
 270                 cuse_lock();
 271                 ptr = TAILQ_FIRST(&cuse_server_head);
 272                 cuse_unlock();
 273
 274                 if (ptr == NULL)
 275                         break;
 276         }
 277
 278         if (cuse_dev != NULL)
 279                 destroy_dev(cuse_dev);
 280
 281         mtx_destroy(&cuse_mtx);
 282 }
 283 SYSUNINIT(cuse_kern_uninit, SI_SUB_DEVFS, SI_ORDER_ANY, cuse_kern_uninit, 0);
 284
 285 static int
 286 cuse_server_get(struct cuse_server **ppcs)
 287 {
 288         struct cuse_server *pcs;
 289         int error;
 290
 291         error = devfs_get_cdevpriv((void **)&pcs);
 292         if (error != 0) {
 293                 *ppcs = NULL;
 294                 return (error);
 295         }
 296         /* check if closing */
 297         cuse_lock();
 298         if (pcs->is_closing) {
 299                 cuse_unlock();
 300                 *ppcs = NULL;
 301                 return (EINVAL);
 302         }
 303         cuse_unlock();
 304         *ppcs = pcs;
 305         return (0);
 306 }
 307
 308 static void
 309 cuse_server_is_closing(struct cuse_server *pcs)
 310 {
 311         struct cuse_client *pcc;
 312
 313         if (pcs->is_closing)
 314                 return;
 315
 316         pcs->is_closing = 1;
 317
 318         TAILQ_FOREACH(pcc, &pcs->hcli, entry) {
 319                 cuse_client_is_closing(pcc);
 320         }
 321 }
 322
 323 static struct cuse_client_command *
 324 cuse_server_find_command(struct cuse_server *pcs, struct thread *td)
 325 {
 326         struct cuse_client *pcc;
 327         int n;
 328
 329         if (pcs->is_closing)
 330                 goto done;
 331
 332         TAILQ_FOREACH(pcc, &pcs->hcli, entry) {
 333                 if (CUSE_CLIENT_CLOSING(pcc))
 334                         continue;
 335                 for (n = 0; n != CUSE_CMD_MAX; n++) {
 336                         if (pcc->cmds[n].entered == td)
 337                                 return (&pcc->cmds[n]);
 338                 }
 339         }
 340 done:
 341         return (NULL);
 342 }
 343
 344 static void
 345 cuse_str_filter(char *ptr)
 346 {
 347         int c;
 348
 349         while (((c = *ptr) != 0)) {
 350
 351                 if ((c >= 'a') && (c <= 'z')) {
 352                         ptr++;
 353                         continue;
 354                 }
 355                 if ((c >= 'A') && (c <= 'Z')) {
 356                         ptr++;
 357                         continue;
 358                 }
 359                 if ((c >= '0') && (c <= '9')) {
 360                         ptr++;
 361                         continue;
 362                 }
 363                 if ((c == '.') || (c == '_') || (c == '/')) {
 364                         ptr++;
 365                         continue;
 366                 }
 367                 *ptr = '_';
 368
 369                 ptr++;
 370         }
 371 }
 372
 373 static int
 374 cuse_convert_error(int error)
 375 {
 376         ;                               /* indent fix */
 377         switch (error) {
 378         case CUSE_ERR_NONE:
 379                 return (0);
 380         case CUSE_ERR_BUSY:
 381                 return (EBUSY);
 382         case CUSE_ERR_WOULDBLOCK:
 383                 return (EWOULDBLOCK);
 384         case CUSE_ERR_INVALID:
 385                 return (EINVAL);
 386         case CUSE_ERR_NO_MEMORY:
 387                 return (ENOMEM);
 388         case CUSE_ERR_FAULT:
 389                 return (EFAULT);
 390         case CUSE_ERR_SIGNAL:
 391                 return (EINTR);
 392         case CUSE_ERR_NO_DEVICE:
 393                 return (ENODEV);
 394         default:
 395                 return (ENXIO);
 396         }
 397 }
 398
 399 static void
 400 cuse_vm_memory_free(struct cuse_memory *mem)
 401 {
 402         /* last user is gone - free */
 403         vm_object_deallocate(mem->object);
 404
 405         /* free CUSE memory */
 406         free(mem, M_CUSE);
 407 }
 408
 409 static int
 410 cuse_server_alloc_memory(struct cuse_server *pcs, uint32_t alloc_nr,
 411     uint32_t page_count)
 412 {
 413         struct cuse_memory *temp;
 414         struct cuse_memory *mem;
 415         vm_object_t object;
 416         int error;
 417
 418         mem = malloc(sizeof(*mem), M_CUSE, M_WAITOK | M_ZERO);
 419         if (mem == NULL)
 420                 return (ENOMEM);
 421
 422         object = vm_pager_allocate(OBJT_SWAP, NULL, PAGE_SIZE * page_count,
 423             VM_PROT_DEFAULT, 0, curthread->td_ucred);
 424         if (object == NULL) {
 425                 error = ENOMEM;
 426                 goto error_0;
 427         }
 428
 429         cuse_lock();
 430         /* check if allocation number already exists */
 431         TAILQ_FOREACH(temp, &pcs->hmem, entry) {
 432                 if (temp->alloc_nr == alloc_nr)
 433                         break;
 434         }
 435         if (temp != NULL) {
 436                 cuse_unlock();
 437                 error = EBUSY;
 438                 goto error_1;
 439         }
 440         mem->object = object;
 441         mem->page_count = page_count;
 442         mem->alloc_nr = alloc_nr;
 443         TAILQ_INSERT_TAIL(&pcs->hmem, mem, entry);
 444         cuse_unlock();
 445
 446         return (0);
 447
 448 error_1:
 449         vm_object_deallocate(object);
 450 error_0:
 451         free(mem, M_CUSE);
 452         return (error);
 453 }
 454
 455 static int
 456 cuse_server_free_memory(struct cuse_server *pcs, uint32_t alloc_nr)
 457 {
 458         struct cuse_memory *mem;
 459
 460         cuse_lock();
 461         TAILQ_FOREACH(mem, &pcs->hmem, entry) {
 462                 if (mem->alloc_nr == alloc_nr)
 463                         break;
 464         }
 465         if (mem == NULL) {
 466                 cuse_unlock();
 467                 return (EINVAL);
 468         }
 469         TAILQ_REMOVE(&pcs->hmem, mem, entry);
 470         cuse_unlock();
 471
 472         cuse_vm_memory_free(mem);
 473
 474         return (0);
 475 }
 476
 477 static int
 478 cuse_client_get(struct cuse_client **ppcc)
 479 {
 480         struct cuse_client *pcc;
 481         int error;
 482
 483         /* try to get private data */
 484         error = devfs_get_cdevpriv((void **)&pcc);
 485         if (error != 0) {
 486                 *ppcc = NULL;
 487                 return (error);
 488         }
 489         /* check if closing */
 490         cuse_lock();
 491         if (CUSE_CLIENT_CLOSING(pcc) || pcc->server->is_closing) {
 492                 cuse_unlock();
 493                 *ppcc = NULL;
 494                 return (EINVAL);
 495         }
 496         cuse_unlock();
 497         *ppcc = pcc;
 498         return (0);
 499 }
 500
 501 static void
 502 cuse_client_is_closing(struct cuse_client *pcc)
 503 {
 504         struct cuse_client_command *pccmd;
 505         uint32_t n;
 506
 507         if (CUSE_CLIENT_CLOSING(pcc))
 508                 return;
 509
 510         pcc->cflags |= CUSE_CLI_IS_CLOSING;
 511         pcc->server_dev = NULL;
 512
 513         for (n = 0; n != CUSE_CMD_MAX; n++) {
 514
 515                 pccmd = &pcc->cmds[n];
 516
 517                 if (pccmd->entry.tqe_prev != NULL) {
 518                         TAILQ_REMOVE(&pcc->server->head, pccmd, entry);
 519                         pccmd->entry.tqe_prev = NULL;
 520                 }
 521                 cv_broadcast(&pccmd->cv);
 522         }
 523 }
 524
 525 static void
 526 cuse_client_send_command_locked(struct cuse_client_command *pccmd,
 527     uintptr_t data_ptr, unsigned long arg, int fflags, int ioflag)
 528 {
 529         unsigned long cuse_fflags = 0;
 530         struct cuse_server *pcs;
 531
 532         if (fflags & FREAD)
 533                 cuse_fflags |= CUSE_FFLAG_READ;
 534
 535         if (fflags & FWRITE)
 536                 cuse_fflags |= CUSE_FFLAG_WRITE;
 537
 538         if (ioflag & IO_NDELAY)
 539                 cuse_fflags |= CUSE_FFLAG_NONBLOCK;
 540 #if defined(__LP64__)
 541         if (SV_CURPROC_FLAG(SV_ILP32))
 542                 cuse_fflags |= CUSE_FFLAG_COMPAT32;
 543 #endif
 544         pccmd->sub.fflags = cuse_fflags;
 545         pccmd->sub.data_pointer = data_ptr;
 546         pccmd->sub.argument = arg;
 547
 548         pcs = pccmd->client->server;
 549
 550         if ((pccmd->entry.tqe_prev == NULL) &&
 551             (CUSE_CLIENT_CLOSING(pccmd->client) == 0) &&
 552             (pcs->is_closing == 0)) {
 553                 TAILQ_INSERT_TAIL(&pcs->head, pccmd, entry);
 554                 cv_signal(&pcs->cv);
 555         }
 556 }
 557
 558 static void
 559 cuse_client_got_signal(struct cuse_client_command *pccmd)
 560 {
 561         struct cuse_server *pcs;
 562
 563         pccmd->got_signal = 1;
 564
 565         pccmd = &pccmd->client->cmds[CUSE_CMD_SIGNAL];
 566
 567         pcs = pccmd->client->server;
 568
 569         if ((pccmd->entry.tqe_prev == NULL) &&
 570             (CUSE_CLIENT_CLOSING(pccmd->client) == 0) &&
 571             (pcs->is_closing == 0)) {
 572                 TAILQ_INSERT_TAIL(&pcs->head, pccmd, entry);
 573                 cv_signal(&pcs->cv);
 574         }
 575 }
 576
 577 static int
 578 cuse_client_receive_command_locked(struct cuse_client_command *pccmd,
 579     uint8_t *arg_ptr, uint32_t arg_len)
 580 {
 581         int error;
 582
 583         error = 0;
 584
 585         pccmd->proc_curr = curthread->td_proc;
 586
 587         if (CUSE_CLIENT_CLOSING(pccmd->client) ||
 588             pccmd->client->server->is_closing) {
 589                 error = CUSE_ERR_OTHER;
 590                 goto done;
 591         }
 592         while (pccmd->command == CUSE_CMD_NONE) {
 593                 if (error != 0) {
 594                         cv_wait(&pccmd->cv, &cuse_mtx);
 595                 } else {
 596                         error = cv_wait_sig(&pccmd->cv, &cuse_mtx);
 597
 598                         if (error != 0)
 599                                 cuse_client_got_signal(pccmd);
 600                 }
 601                 if (CUSE_CLIENT_CLOSING(pccmd->client) ||
 602                     pccmd->client->server->is_closing) {
 603                         error = CUSE_ERR_OTHER;
 604                         goto done;
 605                 }
 606         }
 607
 608         error = pccmd->error;
 609         pccmd->command = CUSE_CMD_NONE;
 610         cv_signal(&pccmd->cv);
 611
 612 done:
 613
 614         /* wait until all process references are gone */
 615
 616         pccmd->proc_curr = NULL;
 617
 618         while (pccmd->proc_refs != 0)
 619                 cv_wait(&pccmd->cv, &cuse_mtx);
 620
 621         return (error);
 622 }
 623
 624 /*------------------------------------------------------------------------*
 625  *      CUSE SERVER PART
 626  *------------------------------------------------------------------------*/
 627
 628 static void
 629 cuse_server_free_dev(struct cuse_server_dev *pcsd)
 630 {
 631         struct cuse_server *pcs;
 632         struct cuse_client *pcc;
 633
 634         /* get server pointer */
 635         pcs = pcsd->server;
 636
 637         /* prevent creation of more devices */
 638         cuse_lock();
 639         if (pcsd->kern_dev != NULL)
 640                 pcsd->kern_dev->si_drv1 = NULL;
 641
 642         TAILQ_FOREACH(pcc, &pcs->hcli, entry) {
 643                 if (pcc->server_dev == pcsd)
 644                         cuse_client_is_closing(pcc);
 645         }
 646         cuse_unlock();
 647
 648         /* destroy device, if any */
 649         if (pcsd->kern_dev != NULL) {
 650                 /* destroy device synchronously */
 651                 destroy_dev(pcsd->kern_dev);
 652         }
 653         free(pcsd, M_CUSE);
 654 }
 655
 656 static void
 657 cuse_server_unref(struct cuse_server *pcs)
 658 {
 659         struct cuse_server_dev *pcsd;
 660         struct cuse_memory *mem;
 661
 662         cuse_lock();
 663         pcs->refs--;
 664         if (pcs->refs != 0) {
 665                 cuse_unlock();
 666                 return;
 667         }
 668         cuse_server_is_closing(pcs);
 669         /* final client wakeup, if any */
 670         cuse_server_wakeup_all_client_locked(pcs);
 671
 672         TAILQ_REMOVE(&cuse_server_head, pcs, entry);
 673
 674         cuse_free_unit_by_id_locked(pcs, -1);
 675
 676         while ((pcsd = TAILQ_FIRST(&pcs->hdev)) != NULL) {
 677                 TAILQ_REMOVE(&pcs->hdev, pcsd, entry);
 678                 cuse_unlock();
 679                 cuse_server_free_dev(pcsd);
 680                 cuse_lock();
 681         }
 682
 683         while ((mem = TAILQ_FIRST(&pcs->hmem)) != NULL) {
 684                 TAILQ_REMOVE(&pcs->hmem, mem, entry);
 685                 cuse_unlock();
 686                 cuse_vm_memory_free(mem);
 687                 cuse_lock();
 688         }
 689
 690         knlist_clear(&pcs->selinfo.si_note, 1);
 691         knlist_destroy(&pcs->selinfo.si_note);
 692
 693         cuse_unlock();
 694
 695         seldrain(&pcs->selinfo);
 696
 697         cv_destroy(&pcs->cv);
 698
 699         free(pcs, M_CUSE);
 700 }
 701
 702 static void
 703 cuse_server_free(void *arg)
 704 {
 705         struct cuse_server *pcs = arg;
 706
 707         /* drop refcount */
 708         cuse_server_unref(pcs);
 709 }
 710
 711 static int
 712 cuse_server_open(struct cdev *dev, int fflags, int devtype, struct thread *td)
 713 {
 714         struct cuse_server *pcs;
 715
 716         pcs = malloc(sizeof(*pcs), M_CUSE, M_WAITOK | M_ZERO);
 717         if (pcs == NULL)
 718                 return (ENOMEM);
 719
 720         if (devfs_set_cdevpriv(pcs, &cuse_server_free)) {
 721                 printf("Cuse: Cannot set cdevpriv.\n");
 722                 free(pcs, M_CUSE);
 723                 return (ENOMEM);
 724         }
 725         /* store current process ID */
 726         pcs->pid = curproc->p_pid;
 727
 728         TAILQ_INIT(&pcs->head);
 729         TAILQ_INIT(&pcs->hdev);
 730         TAILQ_INIT(&pcs->hcli);
 731         TAILQ_INIT(&pcs->hmem);
 732
 733         cv_init(&pcs->cv, "cuse-server-cv");
 734
 735         knlist_init_mtx(&pcs->selinfo.si_note, &cuse_mtx);
 736
 737         cuse_lock();
 738         pcs->refs++;
 739         TAILQ_INSERT_TAIL(&cuse_server_head, pcs, entry);
 740         cuse_unlock();
 741
 742         return (0);
 743 }
 744
 745 static int
 746 cuse_server_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
 747 {
 748         struct cuse_server *pcs;
 749         int error;
 750
 751         error = cuse_server_get(&pcs);
 752         if (error != 0)
 753                 goto done;
 754
 755         cuse_lock();
 756         cuse_server_is_closing(pcs);
 757         /* final client wakeup, if any */
 758         cuse_server_wakeup_all_client_locked(pcs);
 759
 760         knlist_clear(&pcs->selinfo.si_note, 1);
 761         cuse_unlock();
 762
 763 done:
 764         return (0);
 765 }
 766
 767 static int
 768 cuse_server_read(struct cdev *dev, struct uio *uio, int ioflag)
 769 {
 770         return (ENXIO);
 771 }
 772
 773 static int
 774 cuse_server_write(struct cdev *dev, struct uio *uio, int ioflag)
 775 {
 776         return (ENXIO);
 777 }
 778
 779 static int
 780 cuse_server_ioctl_copy_locked(struct cuse_client_command *pccmd,
 781     struct cuse_data_chunk *pchk, int isread)
 782 {
 783         struct proc *p_proc;
 784         uint32_t offset;
 785         int error;
 786
 787         offset = pchk->peer_ptr - CUSE_BUF_MIN_PTR;
 788
 789         if (pchk->length > CUSE_BUFFER_MAX)
 790                 return (EFAULT);
 791
 792         if (offset >= CUSE_BUFFER_MAX)
 793                 return (EFAULT);
 794
 795         if ((offset + pchk->length) > CUSE_BUFFER_MAX)
 796                 return (EFAULT);
 797
 798         p_proc = pccmd->proc_curr;
 799         if (p_proc == NULL)
 800                 return (ENXIO);
 801
 802         if (pccmd->proc_refs < 0)
 803                 return (ENOMEM);
 804
 805         pccmd->proc_refs++;
 806
 807         cuse_unlock();
 808
 809         if (isread == 0) {
 810                 error = copyin(
 811                     (void *)pchk->local_ptr,
 812                     pccmd->client->ioctl_buffer + offset,
 813                     pchk->length);
 814         } else {
 815                 error = copyout(
 816                     pccmd->client->ioctl_buffer + offset,
 817                     (void *)pchk->local_ptr,
 818                     pchk->length);
 819         }
 820
 821         cuse_lock();
 822
 823         pccmd->proc_refs--;
 824
 825         if (pccmd->proc_curr == NULL)
 826                 cv_signal(&pccmd->cv);
 827
 828         return (error);
 829 }
 830
 831 static int
 832 cuse_proc2proc_copy(struct proc *proc_s, vm_offset_t data_s,
 833     struct proc *proc_d, vm_offset_t data_d, size_t len)
 834 {
 835         struct thread *td;
 836         struct proc *proc_cur;
 837         int error;
 838
 839         td = curthread;
 840         proc_cur = td->td_proc;
 841
 842         if (proc_cur == proc_d) {
 843                 struct iovec iov = {
 844                         .iov_base = (caddr_t)data_d,
 845                         .iov_len = len,
 846                 };
 847                 struct uio uio = {
 848                         .uio_iov = &iov,
 849                         .uio_iovcnt = 1,
 850                         .uio_offset = (off_t)data_s,
 851                         .uio_resid = len,
 852                         .uio_segflg = UIO_USERSPACE,
 853                         .uio_rw = UIO_READ,
 854                         .uio_td = td,
 855                 };
 856
 857                 PHOLD(proc_s);
 858                 error = proc_rwmem(proc_s, &uio);
 859                 PRELE(proc_s);
 860
 861         } else if (proc_cur == proc_s) {
 862                 struct iovec iov = {
 863                         .iov_base = (caddr_t)data_s,
 864                         .iov_len = len,
 865                 };
 866                 struct uio uio = {
 867                         .uio_iov = &iov,
 868                         .uio_iovcnt = 1,
 869                         .uio_offset = (off_t)data_d,
 870                         .uio_resid = len,
 871                         .uio_segflg = UIO_USERSPACE,
 872                         .uio_rw = UIO_WRITE,
 873                         .uio_td = td,
 874                 };
 875
 876                 PHOLD(proc_d);
 877                 error = proc_rwmem(proc_d, &uio);
 878                 PRELE(proc_d);
 879         } else {
 880                 error = EINVAL;
 881         }
 882         return (error);
 883 }
 884
 885 static int
 886 cuse_server_data_copy_locked(struct cuse_client_command *pccmd,
 887     struct cuse_data_chunk *pchk, int isread)
 888 {
 889         struct proc *p_proc;
 890         int error;
 891
 892         p_proc = pccmd->proc_curr;
 893         if (p_proc == NULL)
 894                 return (ENXIO);
 895
 896         if (pccmd->proc_refs < 0)
 897                 return (ENOMEM);
 898
 899         pccmd->proc_refs++;
 900
 901         cuse_unlock();
 902
 903         if (isread == 0) {
 904                 error = cuse_proc2proc_copy(
 905                     curthread->td_proc, pchk->local_ptr,
 906                     p_proc, pchk->peer_ptr,
 907                     pchk->length);
 908         } else {
 909                 error = cuse_proc2proc_copy(
 910                     p_proc, pchk->peer_ptr,
 911                     curthread->td_proc, pchk->local_ptr,
 912                     pchk->length);
 913         }
 914
 915         cuse_lock();
 916
 917         pccmd->proc_refs--;
 918
 919         if (pccmd->proc_curr == NULL)
 920                 cv_signal(&pccmd->cv);
 921
 922         return (error);
 923 }
 924
 925 static int
 926 cuse_alloc_unit_by_id_locked(struct cuse_server *pcs, int id)
 927 {
 928         int n;
 929         int x = 0;
 930         int match;
 931
 932         do {
 933                 for (match = n = 0; n != CUSE_DEVICES_MAX; n++) {
 934                         if (cuse_alloc_unit[n] != NULL) {
 935                                 if ((cuse_alloc_unit_id[n] ^ id) & CUSE_ID_MASK)
 936                                         continue;
 937                                 if ((cuse_alloc_unit_id[n] & ~CUSE_ID_MASK) == x) {
 938                                         x++;
 939                                         match = 1;
 940                                 }
 941                         }
 942                 }
 943         } while (match);
 944
 945         if (x < 256) {
 946                 for (n = 0; n != CUSE_DEVICES_MAX; n++) {
 947                         if (cuse_alloc_unit[n] == NULL) {
 948                                 cuse_alloc_unit[n] = pcs;
 949                                 cuse_alloc_unit_id[n] = id | x;
 950                                 return (x);
 951                         }
 952                 }
 953         }
 954         return (-1);
 955 }
 956
 957 static void
 958 cuse_server_wakeup_locked(struct cuse_server *pcs)
 959 {
 960         selwakeup(&pcs->selinfo);
 961         KNOTE_LOCKED(&pcs->selinfo.si_note, 0);
 962 }
 963
 964 static void
 965 cuse_server_wakeup_all_client_locked(struct cuse_server *pcs)
 966 {
 967         struct cuse_client *pcc;
 968
 969         TAILQ_FOREACH(pcc, &pcs->hcli, entry) {
 970                 pcc->cflags |= (CUSE_CLI_KNOTE_NEED_READ |
 971                     CUSE_CLI_KNOTE_NEED_WRITE);
 972         }
 973         cuse_server_wakeup_locked(pcs);
 974 }
 975
 976 static int
 977 cuse_free_unit_by_id_locked(struct cuse_server *pcs, int id)
 978 {
 979         int n;
 980         int found = 0;
 981
 982         for (n = 0; n != CUSE_DEVICES_MAX; n++) {
 983                 if (cuse_alloc_unit[n] == pcs) {
 984                         if (cuse_alloc_unit_id[n] == id || id == -1) {
 985                                 cuse_alloc_unit[n] = NULL;
 986                                 cuse_alloc_unit_id[n] = 0;
 987                                 found = 1;
 988                         }
 989                 }
 990         }
 991
 992         return (found ? 0 : EINVAL);
 993 }
 994
 995 static int
 996 cuse_server_ioctl(struct cdev *dev, unsigned long cmd,
 997     caddr_t data, int fflag, struct thread *td)
 998 {
 999         struct cuse_server *pcs;
1000         int error;
1001
1002         error = cuse_server_get(&pcs);
1003         if (error != 0)
1004                 return (error);
1005
1006         switch (cmd) {
1007                 struct cuse_client_command *pccmd;
1008                 struct cuse_client *pcc;
1009                 struct cuse_command *pcmd;
1010                 struct cuse_alloc_info *pai;
1011                 struct cuse_create_dev *pcd;
1012                 struct cuse_server_dev *pcsd;
1013                 struct cuse_data_chunk *pchk;
1014                 int n;
1015
1016         case CUSE_IOCTL_GET_COMMAND:
1017                 pcmd = (void *)data;
1018
1019                 cuse_lock();
1020
1021                 while ((pccmd = TAILQ_FIRST(&pcs->head)) == NULL) {
1022                         error = cv_wait_sig(&pcs->cv, &cuse_mtx);
1023
1024                         if (pcs->is_closing)
1025                                 error = ENXIO;
1026
1027                         if (error) {
1028                                 cuse_unlock();
1029                                 return (error);
1030                         }
1031                 }
1032
1033                 TAILQ_REMOVE(&pcs->head, pccmd, entry);
1034                 pccmd->entry.tqe_prev = NULL;
1035
1036                 pccmd->entered = curthread;
1037
1038                 *pcmd = pccmd->sub;
1039
1040                 cuse_unlock();
1041
1042                 break;
1043
1044         case CUSE_IOCTL_SYNC_COMMAND:
1045
1046                 cuse_lock();
1047                 while ((pccmd = cuse_server_find_command(pcs, curthread)) != NULL) {
1048
1049                         /* send sync command */
1050                         pccmd->entered = NULL;
1051                         pccmd->error = *(int *)data;
1052                         pccmd->command = CUSE_CMD_SYNC;
1053
1054                         /* signal peer, if any */
1055                         cv_signal(&pccmd->cv);
1056                 }
1057                 cuse_unlock();
1058
1059                 break;
1060
1061         case CUSE_IOCTL_ALLOC_UNIT:
1062
1063                 cuse_lock();
1064                 n = cuse_alloc_unit_by_id_locked(pcs,
1065                     CUSE_ID_DEFAULT(0));
1066                 cuse_unlock();
1067
1068                 if (n < 0)
1069                         error = ENOMEM;
1070                 else
1071                         *(int *)data = n;
1072                 break;
1073
1074         case CUSE_IOCTL_ALLOC_UNIT_BY_ID:
1075
1076                 n = *(int *)data;
1077
1078                 n = (n & CUSE_ID_MASK);
1079
1080                 cuse_lock();
1081                 n = cuse_alloc_unit_by_id_locked(pcs, n);
1082                 cuse_unlock();
1083
1084                 if (n < 0)
1085                         error = ENOMEM;
1086                 else
1087                         *(int *)data = n;
1088                 break;
1089
1090         case CUSE_IOCTL_FREE_UNIT:
1091
1092                 n = *(int *)data;
1093
1094                 n = CUSE_ID_DEFAULT(n);
1095
1096                 cuse_lock();
1097                 error = cuse_free_unit_by_id_locked(pcs, n);
1098                 cuse_unlock();
1099                 break;
1100
1101         case CUSE_IOCTL_FREE_UNIT_BY_ID:
1102
1103                 n = *(int *)data;
1104
1105                 cuse_lock();
1106                 error = cuse_free_unit_by_id_locked(pcs, n);
1107                 cuse_unlock();
1108                 break;
1109
1110         case CUSE_IOCTL_ALLOC_MEMORY:
1111
1112                 pai = (void *)data;
1113
1114                 if (pai->alloc_nr >= CUSE_ALLOC_UNIT_MAX) {
1115                         error = ENOMEM;
1116                         break;
1117                 }
1118                 if (pai->page_count >= CUSE_ALLOC_PAGES_MAX) {
1119                         error = ENOMEM;
1120                         break;
1121                 }
1122                 error = cuse_server_alloc_memory(pcs,
1123                     pai->alloc_nr, pai->page_count);
1124                 break;
1125
1126         case CUSE_IOCTL_FREE_MEMORY:
1127                 pai = (void *)data;
1128
1129                 if (pai->alloc_nr >= CUSE_ALLOC_UNIT_MAX) {
1130                         error = ENOMEM;
1131                         break;
1132                 }
1133                 error = cuse_server_free_memory(pcs, pai->alloc_nr);
1134                 break;
1135
1136         case CUSE_IOCTL_GET_SIG:
1137
1138                 cuse_lock();
1139                 pccmd = cuse_server_find_command(pcs, curthread);
1140
1141                 if (pccmd != NULL) {
1142                         n = pccmd->got_signal;
1143                         pccmd->got_signal = 0;
1144                 } else {
1145                         n = 0;
1146                 }
1147                 cuse_unlock();
1148
1149                 *(int *)data = n;
1150
1151                 break;
1152
1153         case CUSE_IOCTL_SET_PFH:
1154
1155                 cuse_lock();
1156                 pccmd = cuse_server_find_command(pcs, curthread);
1157
1158                 if (pccmd != NULL) {
1159                         pcc = pccmd->client;
1160                         for (n = 0; n != CUSE_CMD_MAX; n++) {
1161                                 pcc->cmds[n].sub.per_file_handle = *(uintptr_t *)data;
1162                         }
1163                 } else {
1164                         error = ENXIO;
1165                 }
1166                 cuse_unlock();
1167                 break;
1168
1169         case CUSE_IOCTL_CREATE_DEV:
1170
1171                 error = priv_check(curthread, PRIV_DRIVER);
1172                 if (error)
1173                         break;
1174
1175                 pcd = (void *)data;
1176
1177                 /* filter input */
1178
1179                 pcd->devname[sizeof(pcd->devname) - 1] = 0;
1180
1181                 if (pcd->devname[0] == 0) {
1182                         error = EINVAL;
1183                         break;
1184                 }
1185                 cuse_str_filter(pcd->devname);
1186
1187                 pcd->permissions &= 0777;
1188
1189                 /* try to allocate a character device */
1190
1191                 pcsd = malloc(sizeof(*pcsd), M_CUSE, M_WAITOK | M_ZERO);
1192
1193                 if (pcsd == NULL) {
1194                         error = ENOMEM;
1195                         break;
1196                 }
1197                 pcsd->server = pcs;
1198
1199                 pcsd->user_dev = pcd->dev;
1200
1201                 pcsd->kern_dev = make_dev_credf(MAKEDEV_CHECKNAME,
1202                     &cuse_client_devsw, 0, NULL, pcd->user_id, pcd->group_id,
1203                     pcd->permissions, "%s", pcd->devname);
1204
1205                 if (pcsd->kern_dev == NULL) {
1206                         free(pcsd, M_CUSE);
1207                         error = ENOMEM;
1208                         break;
1209                 }
1210                 pcsd->kern_dev->si_drv1 = pcsd;
1211
1212                 cuse_lock();
1213                 TAILQ_INSERT_TAIL(&pcs->hdev, pcsd, entry);
1214                 cuse_unlock();
1215
1216                 break;
1217
1218         case CUSE_IOCTL_DESTROY_DEV:
1219
1220                 error = priv_check(curthread, PRIV_DRIVER);
1221                 if (error)
1222                         break;
1223
1224                 cuse_lock();
1225
1226                 error = EINVAL;
1227
1228                 pcsd = TAILQ_FIRST(&pcs->hdev);
1229                 while (pcsd != NULL) {
1230                         if (pcsd->user_dev == *(struct cuse_dev **)data) {
1231                                 TAILQ_REMOVE(&pcs->hdev, pcsd, entry);
1232                                 cuse_unlock();
1233                                 cuse_server_free_dev(pcsd);
1234                                 cuse_lock();
1235                                 error = 0;
1236                                 pcsd = TAILQ_FIRST(&pcs->hdev);
1237                         } else {
1238                                 pcsd = TAILQ_NEXT(pcsd, entry);
1239                         }
1240                 }
1241
1242                 cuse_unlock();
1243                 break;
1244
1245         case CUSE_IOCTL_WRITE_DATA:
1246         case CUSE_IOCTL_READ_DATA:
1247
1248                 cuse_lock();
1249                 pchk = (struct cuse_data_chunk *)data;
1250
1251                 pccmd = cuse_server_find_command(pcs, curthread);
1252
1253                 if (pccmd == NULL) {
1254                         error = ENXIO;  /* invalid request */
1255                 } else if (pchk->peer_ptr < CUSE_BUF_MIN_PTR) {
1256                         error = EFAULT; /* NULL pointer */
1257                 } else if (pchk->peer_ptr < CUSE_BUF_MAX_PTR) {
1258                         error = cuse_server_ioctl_copy_locked(pccmd,
1259                             pchk, cmd == CUSE_IOCTL_READ_DATA);
1260                 } else {
1261                         error = cuse_server_data_copy_locked(pccmd,
1262                             pchk, cmd == CUSE_IOCTL_READ_DATA);
1263                 }
1264                 cuse_unlock();
1265                 break;
1266
1267         case CUSE_IOCTL_SELWAKEUP:
1268                 cuse_lock();
1269                 /*
1270                  * We don't know which direction caused the event.
1271                  * Wakeup both!
1272                  */
1273                 cuse_server_wakeup_all_client_locked(pcs);
1274                 cuse_unlock();
1275                 break;
1276
1277         default:
1278                 error = ENXIO;
1279                 break;
1280         }
1281         return (error);
1282 }
1283
1284 static int
1285 cuse_server_poll(struct cdev *dev, int events, struct thread *td)
1286 {
1287         return (events & (POLLHUP | POLLPRI | POLLIN |
1288             POLLRDNORM | POLLOUT | POLLWRNORM));
1289 }
1290
1291 static int
1292 cuse_server_mmap_single(struct cdev *dev, vm_ooffset_t *offset,
1293     vm_size_t size, struct vm_object **object, int nprot)
1294 {
1295         uint32_t page_nr = *offset / PAGE_SIZE;
1296         uint32_t alloc_nr = page_nr / CUSE_ALLOC_PAGES_MAX;
1297         struct cuse_memory *mem;
1298         struct cuse_server *pcs;
1299         int error;
1300
1301         error = cuse_server_get(&pcs);
1302         if (error != 0)
1303                 return (error);
1304
1305         cuse_lock();
1306         /* lookup memory structure */
1307         TAILQ_FOREACH(mem, &pcs->hmem, entry) {
1308                 if (mem->alloc_nr == alloc_nr)
1309                         break;
1310         }
1311         if (mem == NULL) {
1312                 cuse_unlock();
1313                 return (ENOMEM);
1314         }
1315         /* verify page offset */
1316         page_nr %= CUSE_ALLOC_PAGES_MAX;
1317         if (page_nr >= mem->page_count) {
1318                 cuse_unlock();
1319                 return (ENXIO);
1320         }
1321         /* verify mmap size */
1322         if ((size % PAGE_SIZE) != 0 || (size < PAGE_SIZE) ||
1323             (size > ((mem->page_count - page_nr) * PAGE_SIZE))) {
1324                 cuse_unlock();
1325                 return (EINVAL);
1326         }
1327         vm_object_reference(mem->object);
1328         *object = mem->object;
1329         cuse_unlock();
1330
1331         /* set new VM object offset to use */
1332         *offset = page_nr * PAGE_SIZE;
1333
1334         /* success */
1335         return (0);
1336 }
1337
1338 /*------------------------------------------------------------------------*
1339  *      CUSE CLIENT PART
1340  *------------------------------------------------------------------------*/
1341 static void
1342 cuse_client_free(void *arg)
1343 {
1344         struct cuse_client *pcc = arg;
1345         struct cuse_client_command *pccmd;
1346         struct cuse_server *pcs;
1347         int n;
1348
1349         cuse_lock();
1350         cuse_client_is_closing(pcc);
1351         TAILQ_REMOVE(&pcc->server->hcli, pcc, entry);
1352         cuse_unlock();
1353
1354         for (n = 0; n != CUSE_CMD_MAX; n++) {
1355
1356                 pccmd = &pcc->cmds[n];
1357
1358                 sx_destroy(&pccmd->sx);
1359                 cv_destroy(&pccmd->cv);
1360         }
1361
1362         pcs = pcc->server;
1363
1364         free(pcc, M_CUSE);
1365
1366         /* drop reference on server */
1367         cuse_server_unref(pcs);
1368 }
1369
1370 static int
1371 cuse_client_open(struct cdev *dev, int fflags, int devtype, struct thread *td)
1372 {
1373         struct cuse_client_command *pccmd;
1374         struct cuse_server_dev *pcsd;
1375         struct cuse_client *pcc;
1376         struct cuse_server *pcs;
1377         struct cuse_dev *pcd;
1378         int error;
1379         int n;
1380
1381         cuse_lock();
1382         pcsd = dev->si_drv1;
1383         if (pcsd != NULL) {
1384                 pcs = pcsd->server;
1385                 pcd = pcsd->user_dev;
1386                 /*
1387                  * Check that the refcount didn't wrap and that the
1388                  * same process is not both client and server. This
1389                  * can easily lead to deadlocks when destroying the
1390                  * CUSE character device nodes:
1391                  */
1392                 pcs->refs++;
1393                 if (pcs->refs < 0 || pcs->pid == curproc->p_pid) {
1394                         /* overflow or wrong PID */
1395                         pcs->refs--;
1396                         pcsd = NULL;
1397                 }
1398         } else {
1399                 pcs = NULL;
1400                 pcd = NULL;
1401         }
1402         cuse_unlock();
1403
1404         if (pcsd == NULL)
1405                 return (EINVAL);
1406
1407         pcc = malloc(sizeof(*pcc), M_CUSE, M_WAITOK | M_ZERO);
1408         if (pcc == NULL) {
1409                 /* drop reference on server */
1410                 cuse_server_unref(pcs);
1411                 return (ENOMEM);
1412         }
1413         if (devfs_set_cdevpriv(pcc, &cuse_client_free)) {
1414                 printf("Cuse: Cannot set cdevpriv.\n");
1415                 /* drop reference on server */
1416                 cuse_server_unref(pcs);
1417                 free(pcc, M_CUSE);
1418                 return (ENOMEM);
1419         }
1420         pcc->fflags = fflags;
1421         pcc->server_dev = pcsd;
1422         pcc->server = pcs;
1423
1424         for (n = 0; n != CUSE_CMD_MAX; n++) {
1425
1426                 pccmd = &pcc->cmds[n];
1427
1428                 pccmd->sub.dev = pcd;
1429                 pccmd->sub.command = n;
1430                 pccmd->client = pcc;
1431
1432                 sx_init(&pccmd->sx, "cuse-client-sx");
1433                 cv_init(&pccmd->cv, "cuse-client-cv");
1434         }
1435
1436         cuse_lock();
1437
1438         /* cuse_client_free() assumes that the client is listed somewhere! */
1439         /* always enqueue */
1440
1441         TAILQ_INSERT_TAIL(&pcs->hcli, pcc, entry);
1442
1443         /* check if server is closing */
1444         if ((pcs->is_closing != 0) || (dev->si_drv1 == NULL)) {
1445                 error = EINVAL;
1446         } else {
1447                 error = 0;
1448         }
1449         cuse_unlock();
1450
1451         if (error) {
1452                 devfs_clear_cdevpriv(); /* XXX bugfix */
1453                 return (error);
1454         }
1455         pccmd = &pcc->cmds[CUSE_CMD_OPEN];
1456
1457         cuse_cmd_lock(pccmd);
1458
1459         cuse_lock();
1460         cuse_client_send_command_locked(pccmd, 0, 0, pcc->fflags, 0);
1461
1462         error = cuse_client_receive_command_locked(pccmd, 0, 0);
1463         cuse_unlock();
1464
1465         if (error < 0) {
1466                 error = cuse_convert_error(error);
1467         } else {
1468                 error = 0;
1469         }
1470
1471         cuse_cmd_unlock(pccmd);
1472
1473         if (error)
1474                 devfs_clear_cdevpriv(); /* XXX bugfix */
1475
1476         return (error);
1477 }
1478
1479 static int
1480 cuse_client_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
1481 {
1482         struct cuse_client_command *pccmd;
1483         struct cuse_client *pcc;
1484         int error;
1485
1486         error = cuse_client_get(&pcc);
1487         if (error != 0)
1488                 return (0);
1489
1490         pccmd = &pcc->cmds[CUSE_CMD_CLOSE];
1491
1492         cuse_cmd_lock(pccmd);
1493
1494         cuse_lock();
1495         cuse_client_send_command_locked(pccmd, 0, 0, pcc->fflags, 0);
1496
1497         error = cuse_client_receive_command_locked(pccmd, 0, 0);
1498         cuse_unlock();
1499
1500         cuse_cmd_unlock(pccmd);
1501
1502         cuse_lock();
1503         cuse_client_is_closing(pcc);
1504         cuse_unlock();
1505
1506         return (0);
1507 }
1508
1509 static void
1510 cuse_client_kqfilter_poll(struct cdev *dev, struct cuse_client *pcc)
1511 {
1512         int temp;
1513
1514         cuse_lock();
1515         temp = (pcc->cflags & (CUSE_CLI_KNOTE_HAS_READ |
1516             CUSE_CLI_KNOTE_HAS_WRITE));
1517         pcc->cflags &= ~(CUSE_CLI_KNOTE_NEED_READ |
1518             CUSE_CLI_KNOTE_NEED_WRITE);
1519         cuse_unlock();
1520
1521         if (temp != 0) {
1522                 /* get the latest polling state from the server */
1523                 temp = cuse_client_poll(dev, POLLIN | POLLOUT, NULL);
1524
1525                 if (temp & (POLLIN | POLLOUT)) {
1526                         cuse_lock();
1527                         if (temp & POLLIN)
1528                                 pcc->cflags |= CUSE_CLI_KNOTE_NEED_READ;
1529                         if (temp & POLLOUT)
1530                                 pcc->cflags |= CUSE_CLI_KNOTE_NEED_WRITE;
1531
1532                         /* make sure the "knote" gets woken up */
1533                         cuse_server_wakeup_locked(pcc->server);
1534                         cuse_unlock();
1535                 }
1536         }
1537 }
1538
1539 static int
1540 cuse_client_read(struct cdev *dev, struct uio *uio, int ioflag)
1541 {
1542         struct cuse_client_command *pccmd;
1543         struct cuse_client *pcc;
1544         int error;
1545         int len;
1546
1547         error = cuse_client_get(&pcc);
1548         if (error != 0)
1549                 return (error);
1550
1551         pccmd = &pcc->cmds[CUSE_CMD_READ];
1552
1553         if (uio->uio_segflg != UIO_USERSPACE) {
1554                 return (EINVAL);
1555         }
1556         uio->uio_segflg = UIO_NOCOPY;
1557
1558         cuse_cmd_lock(pccmd);
1559
1560         while (uio->uio_resid != 0) {
1561
1562                 if (uio->uio_iov->iov_len > CUSE_LENGTH_MAX) {
1563                         error = ENOMEM;
1564                         break;
1565                 }
1566                 len = uio->uio_iov->iov_len;
1567
1568                 cuse_lock();
1569                 cuse_client_send_command_locked(pccmd,
1570                     (uintptr_t)uio->uio_iov->iov_base,
1571                     (unsigned long)(unsigned int)len, pcc->fflags, ioflag);
1572
1573                 error = cuse_client_receive_command_locked(pccmd, 0, 0);
1574                 cuse_unlock();
1575
1576                 if (error < 0) {
1577                         error = cuse_convert_error(error);
1578                         break;
1579                 } else if (error == len) {
1580                         error = uiomove(NULL, error, uio);
1581                         if (error)
1582                                 break;
1583                 } else {
1584                         error = uiomove(NULL, error, uio);
1585                         break;
1586                 }
1587         }
1588         cuse_cmd_unlock(pccmd);
1589
1590         uio->uio_segflg = UIO_USERSPACE;/* restore segment flag */
1591
1592         if (error == EWOULDBLOCK)
1593                 cuse_client_kqfilter_poll(dev, pcc);
1594
1595         return (error);
1596 }
1597
1598 static int
1599 cuse_client_write(struct cdev *dev, struct uio *uio, int ioflag)
1600 {
1601         struct cuse_client_command *pccmd;
1602         struct cuse_client *pcc;
1603         int error;
1604         int len;
1605
1606         error = cuse_client_get(&pcc);
1607         if (error != 0)
1608                 return (error);
1609
1610         pccmd = &pcc->cmds[CUSE_CMD_WRITE];
1611
1612         if (uio->uio_segflg != UIO_USERSPACE) {
1613                 return (EINVAL);
1614         }
1615         uio->uio_segflg = UIO_NOCOPY;
1616
1617         cuse_cmd_lock(pccmd);
1618
1619         while (uio->uio_resid != 0) {
1620
1621                 if (uio->uio_iov->iov_len > CUSE_LENGTH_MAX) {
1622                         error = ENOMEM;
1623                         break;
1624                 }
1625                 len = uio->uio_iov->iov_len;
1626
1627                 cuse_lock();
1628                 cuse_client_send_command_locked(pccmd,
1629                     (uintptr_t)uio->uio_iov->iov_base,
1630                     (unsigned long)(unsigned int)len, pcc->fflags, ioflag);
1631
1632                 error = cuse_client_receive_command_locked(pccmd, 0, 0);
1633                 cuse_unlock();
1634
1635                 if (error < 0) {
1636                         error = cuse_convert_error(error);
1637                         break;
1638                 } else if (error == len) {
1639                         error = uiomove(NULL, error, uio);
1640                         if (error)
1641                                 break;
1642                 } else {
1643                         error = uiomove(NULL, error, uio);
1644                         break;
1645                 }
1646         }
1647         cuse_cmd_unlock(pccmd);
1648
1649         uio->uio_segflg = UIO_USERSPACE;/* restore segment flag */
1650
1651         if (error == EWOULDBLOCK)
1652                 cuse_client_kqfilter_poll(dev, pcc);
1653
1654         return (error);
1655 }
1656
1657 int
1658 cuse_client_ioctl(struct cdev *dev, unsigned long cmd,
1659     caddr_t data, int fflag, struct thread *td)
1660 {
1661         struct cuse_client_command *pccmd;
1662         struct cuse_client *pcc;
1663         int error;
1664         int len;
1665
1666         error = cuse_client_get(&pcc);
1667         if (error != 0)
1668                 return (error);
1669
1670         len = IOCPARM_LEN(cmd);
1671         if (len > CUSE_BUFFER_MAX)
1672                 return (ENOMEM);
1673
1674         pccmd = &pcc->cmds[CUSE_CMD_IOCTL];
1675
1676         cuse_cmd_lock(pccmd);
1677
1678         if (cmd & (IOC_IN | IOC_VOID))
1679                 memcpy(pcc->ioctl_buffer, data, len);
1680
1681         /*
1682          * When the ioctl-length is zero drivers can pass information
1683          * through the data pointer of the ioctl. Make sure this information
1684          * is forwarded to the driver.
1685          */
1686
1687         cuse_lock();
1688         cuse_client_send_command_locked(pccmd,
1689             (len == 0) ? *(long *)data : CUSE_BUF_MIN_PTR,
1690             (unsigned long)cmd, pcc->fflags,
1691             (fflag & O_NONBLOCK) ? IO_NDELAY : 0);
1692
1693         error = cuse_client_receive_command_locked(pccmd, data, len);
1694         cuse_unlock();
1695
1696         if (error < 0) {
1697                 error = cuse_convert_error(error);
1698         } else {
1699                 error = 0;
1700         }
1701
1702         if (cmd & IOC_OUT)
1703                 memcpy(data, pcc->ioctl_buffer, len);
1704
1705         cuse_cmd_unlock(pccmd);
1706
1707         if (error == EWOULDBLOCK)
1708                 cuse_client_kqfilter_poll(dev, pcc);
1709
1710         return (error);
1711 }
1712
1713 static int
1714 cuse_client_poll(struct cdev *dev, int events, struct thread *td)
1715 {
1716         struct cuse_client_command *pccmd;
1717         struct cuse_client *pcc;
1718         unsigned long temp;
1719         int error;
1720         int revents;
1721
1722         error = cuse_client_get(&pcc);
1723         if (error != 0)
1724                 goto pollnval;
1725
1726         temp = 0;
1727
1728         if (events & (POLLPRI | POLLIN | POLLRDNORM))
1729                 temp |= CUSE_POLL_READ;
1730
1731         if (events & (POLLOUT | POLLWRNORM))
1732                 temp |= CUSE_POLL_WRITE;
1733
1734         if (events & POLLHUP)
1735                 temp |= CUSE_POLL_ERROR;
1736
1737         pccmd = &pcc->cmds[CUSE_CMD_POLL];
1738
1739         cuse_cmd_lock(pccmd);
1740
1741         /* Need to selrecord() first to not loose any events. */
1742         if (temp != 0 && td != NULL)
1743                 selrecord(td, &pcc->server->selinfo);
1744
1745         cuse_lock();
1746         cuse_client_send_command_locked(pccmd,
1747             0, temp, pcc->fflags, IO_NDELAY);
1748
1749         error = cuse_client_receive_command_locked(pccmd, 0, 0);
1750         cuse_unlock();
1751
1752         cuse_cmd_unlock(pccmd);
1753
1754         if (error < 0) {
1755                 goto pollnval;
1756         } else {
1757                 revents = 0;
1758                 if (error & CUSE_POLL_READ)
1759                         revents |= (events & (POLLPRI | POLLIN | POLLRDNORM));
1760                 if (error & CUSE_POLL_WRITE)
1761                         revents |= (events & (POLLOUT | POLLWRNORM));
1762                 if (error & CUSE_POLL_ERROR)
1763                         revents |= (events & POLLHUP);
1764         }
1765         return (revents);
1766
1767 pollnval:
1768         /* XXX many clients don't understand POLLNVAL */
1769         return (events & (POLLHUP | POLLPRI | POLLIN |
1770             POLLRDNORM | POLLOUT | POLLWRNORM));
1771 }
1772
1773 static int
1774 cuse_client_mmap_single(struct cdev *dev, vm_ooffset_t *offset,
1775     vm_size_t size, struct vm_object **object, int nprot)
1776 {
1777         uint32_t page_nr = *offset / PAGE_SIZE;
1778         uint32_t alloc_nr = page_nr / CUSE_ALLOC_PAGES_MAX;
1779         struct cuse_memory *mem;
1780         struct cuse_client *pcc;
1781         int error;
1782
1783         error = cuse_client_get(&pcc);
1784         if (error != 0)
1785                 return (error);
1786
1787         cuse_lock();
1788         /* lookup memory structure */
1789         TAILQ_FOREACH(mem, &pcc->server->hmem, entry) {
1790                 if (mem->alloc_nr == alloc_nr)
1791                         break;
1792         }
1793         if (mem == NULL) {
1794                 cuse_unlock();
1795                 return (ENOMEM);
1796         }
1797         /* verify page offset */
1798         page_nr %= CUSE_ALLOC_PAGES_MAX;
1799         if (page_nr >= mem->page_count) {
1800                 cuse_unlock();
1801                 return (ENXIO);
1802         }
1803         /* verify mmap size */
1804         if ((size % PAGE_SIZE) != 0 || (size < PAGE_SIZE) ||
1805             (size > ((mem->page_count - page_nr) * PAGE_SIZE))) {
1806                 cuse_unlock();
1807                 return (EINVAL);
1808         }
1809         vm_object_reference(mem->object);
1810         *object = mem->object;
1811         cuse_unlock();
1812
1813         /* set new VM object offset to use */
1814         *offset = page_nr * PAGE_SIZE;
1815
1816         /* success */
1817         return (0);
1818 }
1819
1820 static void
1821 cuse_client_kqfilter_read_detach(struct knote *kn)
1822 {
1823         struct cuse_client *pcc;
1824
1825         cuse_lock();
1826         pcc = kn->kn_hook;
1827         knlist_remove(&pcc->server->selinfo.si_note, kn, 1);
1828         cuse_unlock();
1829 }
1830
1831 static void
1832 cuse_client_kqfilter_write_detach(struct knote *kn)
1833 {
1834         struct cuse_client *pcc;
1835
1836         cuse_lock();
1837         pcc = kn->kn_hook;
1838         knlist_remove(&pcc->server->selinfo.si_note, kn, 1);
1839         cuse_unlock();
1840 }
1841
1842 static int
1843 cuse_client_kqfilter_read_event(struct knote *kn, long hint)
1844 {
1845         struct cuse_client *pcc;
1846
1847         mtx_assert(&cuse_mtx, MA_OWNED);
1848
1849         pcc = kn->kn_hook;
1850         return ((pcc->cflags & CUSE_CLI_KNOTE_NEED_READ) ? 1 : 0);
1851 }
1852
1853 static int
1854 cuse_client_kqfilter_write_event(struct knote *kn, long hint)
1855 {
1856         struct cuse_client *pcc;
1857
1858         mtx_assert(&cuse_mtx, MA_OWNED);
1859
1860         pcc = kn->kn_hook;
1861         return ((pcc->cflags & CUSE_CLI_KNOTE_NEED_WRITE) ? 1 : 0);
1862 }
1863
1864 static int
1865 cuse_client_kqfilter(struct cdev *dev, struct knote *kn)
1866 {
1867         struct cuse_client *pcc;
1868         struct cuse_server *pcs;
1869         int error;
1870
1871         error = cuse_client_get(&pcc);
1872         if (error != 0)
1873                 return (error);
1874
1875         cuse_lock();
1876         pcs = pcc->server;
1877         switch (kn->kn_filter) {
1878         case EVFILT_READ:
1879                 pcc->cflags |= CUSE_CLI_KNOTE_HAS_READ;
1880                 kn->kn_hook = pcc;
1881                 kn->kn_fop = &cuse_client_kqfilter_read_ops;
1882                 knlist_add(&pcs->selinfo.si_note, kn, 1);
1883                 break;
1884         case EVFILT_WRITE:
1885                 pcc->cflags |= CUSE_CLI_KNOTE_HAS_WRITE;
1886                 kn->kn_hook = pcc;
1887                 kn->kn_fop = &cuse_client_kqfilter_write_ops;
1888                 knlist_add(&pcs->selinfo.si_note, kn, 1);
1889                 break;
1890         default:
1891                 error = EINVAL;
1892                 break;
1893         }
1894         cuse_unlock();
1895
1896         if (error == 0)
1897                 cuse_client_kqfilter_poll(dev, pcc);
1898         return (error);
1899 }