1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Mostly platform independent upcall operations to Venus: 4 * -- upcalls 5 * -- upcall routines 6 * 7 * Linux 2.0 version 8 * Copyright (C) 1996 Peter J. Braam <braam@maths.ox.ac.uk>, 9 * Michael Callahan <callahan@maths.ox.ac.uk> 10 * 11 * Redone for Linux 2.1 12 * Copyright (C) 1997 Carnegie Mellon University 13 * 14 * Carnegie Mellon University encourages users of this code to contribute 15 * improvements to the Coda project. Contact Peter Braam <coda@cs.cmu.edu>. 16 */ 17 18 #include <linux/signal.h> 19 #include <linux/sched/signal.h> 20 #include <linux/types.h> 21 #include <linux/kernel.h> 22 #include <linux/mm.h> 23 #include <linux/time.h> 24 #include <linux/fs.h> 25 #include <linux/file.h> 26 #include <linux/stat.h> 27 #include <linux/errno.h> 28 #include <linux/string.h> 29 #include <linux/slab.h> 30 #include <linux/mutex.h> 31 #include <linux/uaccess.h> 32 #include <linux/vmalloc.h> 33 #include <linux/vfs.h> 34 35 #include <linux/coda.h> 36 #include "coda_psdev.h" 37 #include "coda_linux.h" 38 #include "coda_cache.h" 39 40 #include "coda_int.h" 41 42 static int coda_upcall(struct venus_comm *vc, int inSize, int *outSize, 43 union inputArgs *buffer); 44 45 static void *alloc_upcall(int opcode, int size) 46 { 47 union inputArgs *inp; 48 49 inp = kvzalloc(size, GFP_KERNEL); 50 if (!inp) 51 return ERR_PTR(-ENOMEM); 52 53 inp->ih.opcode = opcode; 54 inp->ih.pid = task_pid_nr_ns(current, &init_pid_ns); 55 inp->ih.pgid = task_pgrp_nr_ns(current, &init_pid_ns); 56 inp->ih.uid = from_kuid(&init_user_ns, current_fsuid()); 57 58 return (void*)inp; 59 } 60 61 #define UPARG(op)\ 62 do {\ 63 inp = (union inputArgs *)alloc_upcall(op, insize); \ 64 if (IS_ERR(inp)) { return PTR_ERR(inp); }\ 65 outp = (union outputArgs *)(inp); \ 66 outsize = insize; \ 67 } while (0) 68 69 #define INSIZE(tag) sizeof(struct coda_ ## tag ## _in) 70 #define OUTSIZE(tag) sizeof(struct coda_ ## tag ## _out) 71 #define SIZE(tag) max_t(unsigned int, INSIZE(tag), OUTSIZE(tag)) 72 73 74 /* the upcalls */ 75 int venus_rootfid(struct super_block *sb, struct CodaFid *fidp) 76 { 77 union inputArgs *inp; 78 union outputArgs *outp; 79 int insize, outsize, error; 80 81 insize = SIZE(root); 82 UPARG(CODA_ROOT); 83 84 error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); 85 if (!error) 86 *fidp = outp->coda_root.VFid; 87 88 kvfree(inp); 89 return error; 90 } 91 92 int venus_getattr(struct super_block *sb, struct CodaFid *fid, 93 struct coda_vattr *attr) 94 { 95 union inputArgs *inp; 96 union outputArgs *outp; 97 int insize, outsize, error; 98 99 insize = SIZE(getattr); 100 UPARG(CODA_GETATTR); 101 inp->coda_getattr.VFid = *fid; 102 103 error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); 104 if (!error) 105 *attr = outp->coda_getattr.attr; 106 107 kvfree(inp); 108 return error; 109 } 110 111 int venus_setattr(struct super_block *sb, struct CodaFid *fid, 112 struct coda_vattr *vattr) 113 { 114 union inputArgs *inp; 115 union outputArgs *outp; 116 int insize, outsize, error; 117 118 insize = SIZE(setattr); 119 UPARG(CODA_SETATTR); 120 121 inp->coda_setattr.VFid = *fid; 122 inp->coda_setattr.attr = *vattr; 123 124 error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); 125 126 kvfree(inp); 127 return error; 128 } 129 130 int venus_lookup(struct super_block *sb, struct CodaFid *fid, 131 const char *name, int length, int * type, 132 struct CodaFid *resfid) 133 { 134 union inputArgs *inp; 135 union outputArgs *outp; 136 int insize, outsize, error; 137 int offset; 138 139 offset = INSIZE(lookup); 140 insize = max_t(unsigned int, offset + length +1, OUTSIZE(lookup)); 141 UPARG(CODA_LOOKUP); 142 143 inp->coda_lookup.VFid = *fid; 144 inp->coda_lookup.name = offset; 145 inp->coda_lookup.flags = CLU_CASE_SENSITIVE; 146 /* send Venus a null terminated string */ 147 memcpy((char *)(inp) + offset, name, length); 148 *((char *)inp + offset + length) = '\0'; 149 150 error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); 151 if (!error) { 152 *resfid = outp->coda_lookup.VFid; 153 *type = outp->coda_lookup.vtype; 154 } 155 156 kvfree(inp); 157 return error; 158 } 159 160 int venus_close(struct super_block *sb, struct CodaFid *fid, int flags, 161 kuid_t uid) 162 { 163 union inputArgs *inp; 164 union outputArgs *outp; 165 int insize, outsize, error; 166 167 insize = SIZE(release); 168 UPARG(CODA_CLOSE); 169 170 inp->ih.uid = from_kuid(&init_user_ns, uid); 171 inp->coda_close.VFid = *fid; 172 inp->coda_close.flags = flags; 173 174 error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); 175 176 kvfree(inp); 177 return error; 178 } 179 180 int venus_open(struct super_block *sb, struct CodaFid *fid, 181 int flags, struct file **fh) 182 { 183 union inputArgs *inp; 184 union outputArgs *outp; 185 int insize, outsize, error; 186 187 insize = SIZE(open_by_fd); 188 UPARG(CODA_OPEN_BY_FD); 189 190 inp->coda_open_by_fd.VFid = *fid; 191 inp->coda_open_by_fd.flags = flags; 192 193 error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); 194 if (!error) 195 *fh = outp->coda_open_by_fd.fh; 196 197 kvfree(inp); 198 return error; 199 } 200 201 int venus_mkdir(struct super_block *sb, struct CodaFid *dirfid, 202 const char *name, int length, 203 struct CodaFid *newfid, struct coda_vattr *attrs) 204 { 205 union inputArgs *inp; 206 union outputArgs *outp; 207 int insize, outsize, error; 208 int offset; 209 210 offset = INSIZE(mkdir); 211 insize = max_t(unsigned int, offset + length + 1, OUTSIZE(mkdir)); 212 UPARG(CODA_MKDIR); 213 214 inp->coda_mkdir.VFid = *dirfid; 215 inp->coda_mkdir.attr = *attrs; 216 inp->coda_mkdir.name = offset; 217 /* Venus must get null terminated string */ 218 memcpy((char *)(inp) + offset, name, length); 219 *((char *)inp + offset + length) = '\0'; 220 221 error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); 222 if (!error) { 223 *attrs = outp->coda_mkdir.attr; 224 *newfid = outp->coda_mkdir.VFid; 225 } 226 227 kvfree(inp); 228 return error; 229 } 230 231 232 int venus_rename(struct super_block *sb, struct CodaFid *old_fid, 233 struct CodaFid *new_fid, size_t old_length, 234 size_t new_length, const char *old_name, 235 const char *new_name) 236 { 237 union inputArgs *inp; 238 union outputArgs *outp; 239 int insize, outsize, error; 240 int offset, s; 241 242 offset = INSIZE(rename); 243 insize = max_t(unsigned int, offset + new_length + old_length + 8, 244 OUTSIZE(rename)); 245 UPARG(CODA_RENAME); 246 247 inp->coda_rename.sourceFid = *old_fid; 248 inp->coda_rename.destFid = *new_fid; 249 inp->coda_rename.srcname = offset; 250 251 /* Venus must receive an null terminated string */ 252 s = ( old_length & ~0x3) +4; /* round up to word boundary */ 253 memcpy((char *)(inp) + offset, old_name, old_length); 254 *((char *)inp + offset + old_length) = '\0'; 255 256 /* another null terminated string for Venus */ 257 offset += s; 258 inp->coda_rename.destname = offset; 259 s = ( new_length & ~0x3) +4; /* round up to word boundary */ 260 memcpy((char *)(inp) + offset, new_name, new_length); 261 *((char *)inp + offset + new_length) = '\0'; 262 263 error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); 264 265 kvfree(inp); 266 return error; 267 } 268 269 int venus_create(struct super_block *sb, struct CodaFid *dirfid, 270 const char *name, int length, int excl, int mode, 271 struct CodaFid *newfid, struct coda_vattr *attrs) 272 { 273 union inputArgs *inp; 274 union outputArgs *outp; 275 int insize, outsize, error; 276 int offset; 277 278 offset = INSIZE(create); 279 insize = max_t(unsigned int, offset + length + 1, OUTSIZE(create)); 280 UPARG(CODA_CREATE); 281 282 inp->coda_create.VFid = *dirfid; 283 inp->coda_create.attr.va_mode = mode; 284 inp->coda_create.excl = excl; 285 inp->coda_create.mode = mode; 286 inp->coda_create.name = offset; 287 288 /* Venus must get null terminated string */ 289 memcpy((char *)(inp) + offset, name, length); 290 *((char *)inp + offset + length) = '\0'; 291 292 error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); 293 if (!error) { 294 *attrs = outp->coda_create.attr; 295 *newfid = outp->coda_create.VFid; 296 } 297 298 kvfree(inp); 299 return error; 300 } 301 302 int venus_rmdir(struct super_block *sb, struct CodaFid *dirfid, 303 const char *name, int length) 304 { 305 union inputArgs *inp; 306 union outputArgs *outp; 307 int insize, outsize, error; 308 int offset; 309 310 offset = INSIZE(rmdir); 311 insize = max_t(unsigned int, offset + length + 1, OUTSIZE(rmdir)); 312 UPARG(CODA_RMDIR); 313 314 inp->coda_rmdir.VFid = *dirfid; 315 inp->coda_rmdir.name = offset; 316 memcpy((char *)(inp) + offset, name, length); 317 *((char *)inp + offset + length) = '\0'; 318 319 error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); 320 321 kvfree(inp); 322 return error; 323 } 324 325 int venus_remove(struct super_block *sb, struct CodaFid *dirfid, 326 const char *name, int length) 327 { 328 union inputArgs *inp; 329 union outputArgs *outp; 330 int error=0, insize, outsize, offset; 331 332 offset = INSIZE(remove); 333 insize = max_t(unsigned int, offset + length + 1, OUTSIZE(remove)); 334 UPARG(CODA_REMOVE); 335 336 inp->coda_remove.VFid = *dirfid; 337 inp->coda_remove.name = offset; 338 memcpy((char *)(inp) + offset, name, length); 339 *((char *)inp + offset + length) = '\0'; 340 341 error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); 342 343 kvfree(inp); 344 return error; 345 } 346 347 int venus_readlink(struct super_block *sb, struct CodaFid *fid, 348 char *buffer, int *length) 349 { 350 union inputArgs *inp; 351 union outputArgs *outp; 352 int insize, outsize, error; 353 int retlen; 354 char *result; 355 356 insize = max_t(unsigned int, 357 INSIZE(readlink), OUTSIZE(readlink)+ *length); 358 UPARG(CODA_READLINK); 359 360 inp->coda_readlink.VFid = *fid; 361 362 error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); 363 if (!error) { 364 retlen = outp->coda_readlink.count; 365 if (retlen >= *length) 366 retlen = *length - 1; 367 *length = retlen; 368 result = (char *)outp + (long)outp->coda_readlink.data; 369 memcpy(buffer, result, retlen); 370 *(buffer + retlen) = '\0'; 371 } 372 373 kvfree(inp); 374 return error; 375 } 376 377 378 379 int venus_link(struct super_block *sb, struct CodaFid *fid, 380 struct CodaFid *dirfid, const char *name, int len ) 381 { 382 union inputArgs *inp; 383 union outputArgs *outp; 384 int insize, outsize, error; 385 int offset; 386 387 offset = INSIZE(link); 388 insize = max_t(unsigned int, offset + len + 1, OUTSIZE(link)); 389 UPARG(CODA_LINK); 390 391 inp->coda_link.sourceFid = *fid; 392 inp->coda_link.destFid = *dirfid; 393 inp->coda_link.tname = offset; 394 395 /* make sure strings are null terminated */ 396 memcpy((char *)(inp) + offset, name, len); 397 *((char *)inp + offset + len) = '\0'; 398 399 error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); 400 401 kvfree(inp); 402 return error; 403 } 404 405 int venus_symlink(struct super_block *sb, struct CodaFid *fid, 406 const char *name, int len, 407 const char *symname, int symlen) 408 { 409 union inputArgs *inp; 410 union outputArgs *outp; 411 int insize, outsize, error; 412 int offset, s; 413 414 offset = INSIZE(symlink); 415 insize = max_t(unsigned int, offset + len + symlen + 8, OUTSIZE(symlink)); 416 UPARG(CODA_SYMLINK); 417 418 /* inp->coda_symlink.attr = *tva; XXXXXX */ 419 inp->coda_symlink.VFid = *fid; 420 421 /* Round up to word boundary and null terminate */ 422 inp->coda_symlink.srcname = offset; 423 s = ( symlen & ~0x3 ) + 4; 424 memcpy((char *)(inp) + offset, symname, symlen); 425 *((char *)inp + offset + symlen) = '\0'; 426 427 /* Round up to word boundary and null terminate */ 428 offset += s; 429 inp->coda_symlink.tname = offset; 430 s = (len & ~0x3) + 4; 431 memcpy((char *)(inp) + offset, name, len); 432 *((char *)inp + offset + len) = '\0'; 433 434 error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); 435 436 kvfree(inp); 437 return error; 438 } 439 440 int venus_fsync(struct super_block *sb, struct CodaFid *fid) 441 { 442 union inputArgs *inp; 443 union outputArgs *outp; 444 int insize, outsize, error; 445 446 insize=SIZE(fsync); 447 UPARG(CODA_FSYNC); 448 449 inp->coda_fsync.VFid = *fid; 450 error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); 451 452 kvfree(inp); 453 return error; 454 } 455 456 int venus_access(struct super_block *sb, struct CodaFid *fid, int mask) 457 { 458 union inputArgs *inp; 459 union outputArgs *outp; 460 int insize, outsize, error; 461 462 insize = SIZE(access); 463 UPARG(CODA_ACCESS); 464 465 inp->coda_access.VFid = *fid; 466 inp->coda_access.flags = mask; 467 468 error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); 469 470 kvfree(inp); 471 return error; 472 } 473 474 475 int venus_pioctl(struct super_block *sb, struct CodaFid *fid, 476 unsigned int cmd, struct PioctlData *data) 477 { 478 union inputArgs *inp; 479 union outputArgs *outp; 480 int insize, outsize, error; 481 int iocsize; 482 483 insize = VC_MAXMSGSIZE; 484 UPARG(CODA_IOCTL); 485 486 /* build packet for Venus */ 487 if (data->vi.in_size > VC_MAXDATASIZE) { 488 error = -EINVAL; 489 goto exit; 490 } 491 492 if (data->vi.out_size > VC_MAXDATASIZE) { 493 error = -EINVAL; 494 goto exit; 495 } 496 497 inp->coda_ioctl.VFid = *fid; 498 499 /* the cmd field was mutated by increasing its size field to 500 * reflect the path and follow args. We need to subtract that 501 * out before sending the command to Venus. */ 502 inp->coda_ioctl.cmd = (cmd & ~(PIOCPARM_MASK << 16)); 503 iocsize = ((cmd >> 16) & PIOCPARM_MASK) - sizeof(char *) - sizeof(int); 504 inp->coda_ioctl.cmd |= (iocsize & PIOCPARM_MASK) << 16; 505 506 /* in->coda_ioctl.rwflag = flag; */ 507 inp->coda_ioctl.len = data->vi.in_size; 508 inp->coda_ioctl.data = (char *)(INSIZE(ioctl)); 509 510 /* get the data out of user space */ 511 if (copy_from_user((char *)inp + (long)inp->coda_ioctl.data, 512 data->vi.in, data->vi.in_size)) { 513 error = -EINVAL; 514 goto exit; 515 } 516 517 error = coda_upcall(coda_vcp(sb), SIZE(ioctl) + data->vi.in_size, 518 &outsize, inp); 519 520 if (error) { 521 pr_warn("%s: Venus returns: %d for %s\n", 522 __func__, error, coda_f2s(fid)); 523 goto exit; 524 } 525 526 if (outsize < (long)outp->coda_ioctl.data + outp->coda_ioctl.len) { 527 error = -EINVAL; 528 goto exit; 529 } 530 531 /* Copy out the OUT buffer. */ 532 if (outp->coda_ioctl.len > data->vi.out_size) { 533 error = -EINVAL; 534 goto exit; 535 } 536 537 /* Copy out the OUT buffer. */ 538 if (copy_to_user(data->vi.out, 539 (char *)outp + (long)outp->coda_ioctl.data, 540 outp->coda_ioctl.len)) { 541 error = -EFAULT; 542 goto exit; 543 } 544 545 exit: 546 kvfree(inp); 547 return error; 548 } 549 550 int venus_statfs(struct dentry *dentry, struct kstatfs *sfs) 551 { 552 union inputArgs *inp; 553 union outputArgs *outp; 554 int insize, outsize, error; 555 556 insize = SIZE(statfs); 557 UPARG(CODA_STATFS); 558 559 error = coda_upcall(coda_vcp(dentry->d_sb), insize, &outsize, inp); 560 if (!error) { 561 sfs->f_blocks = outp->coda_statfs.stat.f_blocks; 562 sfs->f_bfree = outp->coda_statfs.stat.f_bfree; 563 sfs->f_bavail = outp->coda_statfs.stat.f_bavail; 564 sfs->f_files = outp->coda_statfs.stat.f_files; 565 sfs->f_ffree = outp->coda_statfs.stat.f_ffree; 566 } 567 568 kvfree(inp); 569 return error; 570 } 571 572 int venus_access_intent(struct super_block *sb, struct CodaFid *fid, 573 bool *access_intent_supported, 574 size_t count, loff_t ppos, int type) 575 { 576 union inputArgs *inp; 577 union outputArgs *outp; 578 int insize, outsize, error; 579 bool finalizer = 580 type == CODA_ACCESS_TYPE_READ_FINISH || 581 type == CODA_ACCESS_TYPE_WRITE_FINISH; 582 583 if (!*access_intent_supported && !finalizer) 584 return 0; 585 586 insize = SIZE(access_intent); 587 UPARG(CODA_ACCESS_INTENT); 588 589 inp->coda_access_intent.VFid = *fid; 590 inp->coda_access_intent.count = count; 591 inp->coda_access_intent.pos = ppos; 592 inp->coda_access_intent.type = type; 593 594 error = coda_upcall(coda_vcp(sb), insize, 595 finalizer ? NULL : &outsize, inp); 596 597 /* 598 * we have to free the request buffer for synchronous upcalls 599 * or when asynchronous upcalls fail, but not when asynchronous 600 * upcalls succeed 601 */ 602 if (!finalizer || error) 603 kvfree(inp); 604 605 /* Chunked access is not supported or an old Coda client */ 606 if (error == -EOPNOTSUPP) { 607 *access_intent_supported = false; 608 error = 0; 609 } 610 return error; 611 } 612 613 /* 614 * coda_upcall and coda_downcall routines. 615 */ 616 static void coda_block_signals(sigset_t *old) 617 { 618 spin_lock_irq(¤t->sighand->siglock); 619 *old = current->blocked; 620 621 sigfillset(¤t->blocked); 622 sigdelset(¤t->blocked, SIGKILL); 623 sigdelset(¤t->blocked, SIGSTOP); 624 sigdelset(¤t->blocked, SIGINT); 625 626 recalc_sigpending(); 627 spin_unlock_irq(¤t->sighand->siglock); 628 } 629 630 static void coda_unblock_signals(sigset_t *old) 631 { 632 spin_lock_irq(¤t->sighand->siglock); 633 current->blocked = *old; 634 recalc_sigpending(); 635 spin_unlock_irq(¤t->sighand->siglock); 636 } 637 638 /* Don't allow signals to interrupt the following upcalls before venus 639 * has seen them, 640 * - CODA_CLOSE or CODA_RELEASE upcall (to avoid reference count problems) 641 * - CODA_STORE (to avoid data loss) 642 * - CODA_ACCESS_INTENT (to avoid reference count problems) 643 */ 644 #define CODA_INTERRUPTIBLE(r) (!coda_hard && \ 645 (((r)->uc_opcode != CODA_CLOSE && \ 646 (r)->uc_opcode != CODA_STORE && \ 647 (r)->uc_opcode != CODA_ACCESS_INTENT && \ 648 (r)->uc_opcode != CODA_RELEASE) || \ 649 (r)->uc_flags & CODA_REQ_READ)) 650 651 static inline void coda_waitfor_upcall(struct venus_comm *vcp, 652 struct upc_req *req) 653 { 654 DECLARE_WAITQUEUE(wait, current); 655 unsigned long timeout = jiffies + coda_timeout * HZ; 656 sigset_t old; 657 int blocked; 658 659 coda_block_signals(&old); 660 blocked = 1; 661 662 add_wait_queue(&req->uc_sleep, &wait); 663 for (;;) { 664 if (CODA_INTERRUPTIBLE(req)) 665 set_current_state(TASK_INTERRUPTIBLE); 666 else 667 set_current_state(TASK_UNINTERRUPTIBLE); 668 669 /* got a reply */ 670 if (req->uc_flags & (CODA_REQ_WRITE | CODA_REQ_ABORT)) 671 break; 672 673 if (blocked && time_after(jiffies, timeout) && 674 CODA_INTERRUPTIBLE(req)) 675 { 676 coda_unblock_signals(&old); 677 blocked = 0; 678 } 679 680 if (signal_pending(current)) { 681 list_del(&req->uc_chain); 682 break; 683 } 684 685 mutex_unlock(&vcp->vc_mutex); 686 if (blocked) 687 schedule_timeout(HZ); 688 else 689 schedule(); 690 mutex_lock(&vcp->vc_mutex); 691 } 692 if (blocked) 693 coda_unblock_signals(&old); 694 695 remove_wait_queue(&req->uc_sleep, &wait); 696 set_current_state(TASK_RUNNING); 697 } 698 699 700 /* 701 * coda_upcall will return an error in the case of 702 * failed communication with Venus _or_ will peek at Venus 703 * reply and return Venus' error. 704 * 705 * As venus has 2 types of errors, normal errors (positive) and internal 706 * errors (negative), normal errors are negated, while internal errors 707 * are all mapped to -EINTR, while showing a nice warning message. (jh) 708 */ 709 static int coda_upcall(struct venus_comm *vcp, 710 int inSize, int *outSize, 711 union inputArgs *buffer) 712 { 713 union outputArgs *out; 714 union inputArgs *sig_inputArgs; 715 struct upc_req *req = NULL, *sig_req; 716 int error; 717 718 mutex_lock(&vcp->vc_mutex); 719 720 if (!vcp->vc_inuse) { 721 pr_notice("Venus dead, not sending upcall\n"); 722 error = -ENXIO; 723 goto exit; 724 } 725 726 /* Format the request message. */ 727 req = kmalloc(sizeof(struct upc_req), GFP_KERNEL); 728 if (!req) { 729 error = -ENOMEM; 730 goto exit; 731 } 732 733 buffer->ih.unique = ++vcp->vc_seq; 734 735 req->uc_data = (void *)buffer; 736 req->uc_flags = outSize ? 0 : CODA_REQ_ASYNC; 737 req->uc_inSize = inSize; 738 req->uc_outSize = (outSize && *outSize) ? *outSize : inSize; 739 req->uc_opcode = buffer->ih.opcode; 740 req->uc_unique = buffer->ih.unique; 741 init_waitqueue_head(&req->uc_sleep); 742 743 /* Append msg to pending queue and poke Venus. */ 744 list_add_tail(&req->uc_chain, &vcp->vc_pending); 745 wake_up_interruptible(&vcp->vc_waitq); 746 747 /* We can return early on asynchronous requests */ 748 if (outSize == NULL) { 749 mutex_unlock(&vcp->vc_mutex); 750 return 0; 751 } 752 753 /* We can be interrupted while we wait for Venus to process 754 * our request. If the interrupt occurs before Venus has read 755 * the request, we dequeue and return. If it occurs after the 756 * read but before the reply, we dequeue, send a signal 757 * message, and return. If it occurs after the reply we ignore 758 * it. In no case do we want to restart the syscall. If it 759 * was interrupted by a venus shutdown (psdev_close), return 760 * ENODEV. */ 761 762 /* Go to sleep. Wake up on signals only after the timeout. */ 763 coda_waitfor_upcall(vcp, req); 764 765 /* Op went through, interrupt or not... */ 766 if (req->uc_flags & CODA_REQ_WRITE) { 767 out = (union outputArgs *)req->uc_data; 768 /* here we map positive Venus errors to kernel errors */ 769 error = -out->oh.result; 770 *outSize = req->uc_outSize; 771 goto exit; 772 } 773 774 error = -EINTR; 775 if ((req->uc_flags & CODA_REQ_ABORT) || !signal_pending(current)) { 776 pr_warn("Unexpected interruption.\n"); 777 goto exit; 778 } 779 780 /* Interrupted before venus read it. */ 781 if (!(req->uc_flags & CODA_REQ_READ)) 782 goto exit; 783 784 /* Venus saw the upcall, make sure we can send interrupt signal */ 785 if (!vcp->vc_inuse) { 786 pr_info("Venus dead, not sending signal.\n"); 787 goto exit; 788 } 789 790 error = -ENOMEM; 791 sig_req = kmalloc(sizeof(struct upc_req), GFP_KERNEL); 792 if (!sig_req) goto exit; 793 794 sig_inputArgs = kvzalloc(sizeof(struct coda_in_hdr), GFP_KERNEL); 795 if (!sig_inputArgs) { 796 kfree(sig_req); 797 goto exit; 798 } 799 800 error = -EINTR; 801 sig_inputArgs->ih.opcode = CODA_SIGNAL; 802 sig_inputArgs->ih.unique = req->uc_unique; 803 804 sig_req->uc_flags = CODA_REQ_ASYNC; 805 sig_req->uc_opcode = sig_inputArgs->ih.opcode; 806 sig_req->uc_unique = sig_inputArgs->ih.unique; 807 sig_req->uc_data = (void *)sig_inputArgs; 808 sig_req->uc_inSize = sizeof(struct coda_in_hdr); 809 sig_req->uc_outSize = sizeof(struct coda_in_hdr); 810 811 /* insert at head of queue! */ 812 list_add(&(sig_req->uc_chain), &vcp->vc_pending); 813 wake_up_interruptible(&vcp->vc_waitq); 814 815 exit: 816 kfree(req); 817 mutex_unlock(&vcp->vc_mutex); 818 return error; 819 } 820 821 /* 822 The statements below are part of the Coda opportunistic 823 programming -- taken from the Mach/BSD kernel code for Coda. 824 You don't get correct semantics by stating what needs to be 825 done without guaranteeing the invariants needed for it to happen. 826 When will be have time to find out what exactly is going on? (pjb) 827 */ 828 829 830 /* 831 * There are 7 cases where cache invalidations occur. The semantics 832 * of each is listed here: 833 * 834 * CODA_FLUSH -- flush all entries from the name cache and the cnode cache. 835 * CODA_PURGEUSER -- flush all entries from the name cache for a specific user 836 * This call is a result of token expiration. 837 * 838 * The next arise as the result of callbacks on a file or directory. 839 * CODA_ZAPFILE -- flush the cached attributes for a file. 840 841 * CODA_ZAPDIR -- flush the attributes for the dir and 842 * force a new lookup for all the children 843 of this dir. 844 845 * 846 * The next is a result of Venus detecting an inconsistent file. 847 * CODA_PURGEFID -- flush the attribute for the file 848 * purge it and its children from the dcache 849 * 850 * The last allows Venus to replace local fids with global ones 851 * during reintegration. 852 * 853 * CODA_REPLACE -- replace one CodaFid with another throughout the name cache */ 854 855 int coda_downcall(struct venus_comm *vcp, int opcode, union outputArgs *out, 856 size_t nbytes) 857 { 858 struct inode *inode = NULL; 859 struct CodaFid *fid = NULL, *newfid; 860 struct super_block *sb; 861 862 /* 863 * Make sure we have received enough data from the cache 864 * manager to populate the necessary fields in the buffer 865 */ 866 switch (opcode) { 867 case CODA_PURGEUSER: 868 if (nbytes < sizeof(struct coda_purgeuser_out)) 869 return -EINVAL; 870 break; 871 872 case CODA_ZAPDIR: 873 if (nbytes < sizeof(struct coda_zapdir_out)) 874 return -EINVAL; 875 break; 876 877 case CODA_ZAPFILE: 878 if (nbytes < sizeof(struct coda_zapfile_out)) 879 return -EINVAL; 880 break; 881 882 case CODA_PURGEFID: 883 if (nbytes < sizeof(struct coda_purgefid_out)) 884 return -EINVAL; 885 break; 886 887 case CODA_REPLACE: 888 if (nbytes < sizeof(struct coda_replace_out)) 889 return -EINVAL; 890 break; 891 } 892 893 /* Handle invalidation requests. */ 894 mutex_lock(&vcp->vc_mutex); 895 sb = vcp->vc_sb; 896 if (!sb || !sb->s_root) 897 goto unlock_out; 898 899 switch (opcode) { 900 case CODA_FLUSH: 901 coda_cache_clear_all(sb); 902 shrink_dcache_sb(sb); 903 if (d_really_is_positive(sb->s_root)) 904 coda_flag_inode(d_inode(sb->s_root), C_FLUSH); 905 break; 906 907 case CODA_PURGEUSER: 908 coda_cache_clear_all(sb); 909 break; 910 911 case CODA_ZAPDIR: 912 fid = &out->coda_zapdir.CodaFid; 913 break; 914 915 case CODA_ZAPFILE: 916 fid = &out->coda_zapfile.CodaFid; 917 break; 918 919 case CODA_PURGEFID: 920 fid = &out->coda_purgefid.CodaFid; 921 break; 922 923 case CODA_REPLACE: 924 fid = &out->coda_replace.OldFid; 925 break; 926 } 927 if (fid) 928 inode = coda_fid_to_inode(fid, sb); 929 930 unlock_out: 931 mutex_unlock(&vcp->vc_mutex); 932 933 if (!inode) 934 return 0; 935 936 switch (opcode) { 937 case CODA_ZAPDIR: 938 coda_flag_inode_children(inode, C_PURGE); 939 coda_flag_inode(inode, C_VATTR); 940 break; 941 942 case CODA_ZAPFILE: 943 coda_flag_inode(inode, C_VATTR); 944 break; 945 946 case CODA_PURGEFID: 947 coda_flag_inode_children(inode, C_PURGE); 948 949 /* catch the dentries later if some are still busy */ 950 coda_flag_inode(inode, C_PURGE); 951 d_prune_aliases(inode); 952 break; 953 954 case CODA_REPLACE: 955 newfid = &out->coda_replace.NewFid; 956 coda_replace_fid(inode, fid, newfid); 957 break; 958 } 959 iput(inode); 960 return 0; 961 } 962