| 1 | /* |
| 2 | * fs/cifs/transport.c |
| 3 | * |
| 4 | * Copyright (C) International Business Machines Corp., 2002,2008 |
| 5 | * Author(s): Steve French (sfrench@us.ibm.com) |
| 6 | * Jeremy Allison (jra@samba.org) 2006. |
| 7 | * |
| 8 | * This library is free software; you can redistribute it and/or modify |
| 9 | * it under the terms of the GNU Lesser General Public License as published |
| 10 | * by the Free Software Foundation; either version 2.1 of the License, or |
| 11 | * (at your option) any later version. |
| 12 | * |
| 13 | * This library is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
| 16 | * the GNU Lesser General Public License for more details. |
| 17 | * |
| 18 | * You should have received a copy of the GNU Lesser General Public License |
| 19 | * along with this library; if not, write to the Free Software |
| 20 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 21 | */ |
| 22 | |
| 23 | #include <linux/fs.h> |
| 24 | #include <linux/list.h> |
| 25 | #include <linux/gfp.h> |
| 26 | #include <linux/wait.h> |
| 27 | #include <linux/net.h> |
| 28 | #include <linux/delay.h> |
| 29 | #include <linux/freezer.h> |
| 30 | #include <linux/tcp.h> |
| 31 | #include <linux/highmem.h> |
| 32 | #include <asm/uaccess.h> |
| 33 | #include <asm/processor.h> |
| 34 | #include <linux/mempool.h> |
| 35 | #include "cifspdu.h" |
| 36 | #include "cifsglob.h" |
| 37 | #include "cifsproto.h" |
| 38 | #include "cifs_debug.h" |
| 39 | |
| 40 | void |
| 41 | cifs_wake_up_task(struct mid_q_entry *mid) |
| 42 | { |
| 43 | wake_up_process(mid->callback_data); |
| 44 | } |
| 45 | |
| 46 | struct mid_q_entry * |
| 47 | AllocMidQEntry(const struct smb_hdr *smb_buffer, struct TCP_Server_Info *server) |
| 48 | { |
| 49 | struct mid_q_entry *temp; |
| 50 | |
| 51 | if (server == NULL) { |
| 52 | cifs_dbg(VFS, "Null TCP session in AllocMidQEntry\n"); |
| 53 | return NULL; |
| 54 | } |
| 55 | |
| 56 | temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS); |
| 57 | if (temp == NULL) |
| 58 | return temp; |
| 59 | else { |
| 60 | memset(temp, 0, sizeof(struct mid_q_entry)); |
| 61 | temp->mid = get_mid(smb_buffer); |
| 62 | temp->pid = current->pid; |
| 63 | temp->command = cpu_to_le16(smb_buffer->Command); |
| 64 | cifs_dbg(FYI, "For smb_command %d\n", smb_buffer->Command); |
| 65 | /* do_gettimeofday(&temp->when_sent);*/ /* easier to use jiffies */ |
| 66 | /* when mid allocated can be before when sent */ |
| 67 | temp->when_alloc = jiffies; |
| 68 | temp->server = server; |
| 69 | |
| 70 | /* |
| 71 | * The default is for the mid to be synchronous, so the |
| 72 | * default callback just wakes up the current task. |
| 73 | */ |
| 74 | temp->callback = cifs_wake_up_task; |
| 75 | temp->callback_data = current; |
| 76 | } |
| 77 | |
| 78 | atomic_inc(&midCount); |
| 79 | temp->mid_state = MID_REQUEST_ALLOCATED; |
| 80 | return temp; |
| 81 | } |
| 82 | |
| 83 | void |
| 84 | DeleteMidQEntry(struct mid_q_entry *midEntry) |
| 85 | { |
| 86 | #ifdef CONFIG_CIFS_STATS2 |
| 87 | __le16 command = midEntry->server->vals->lock_cmd; |
| 88 | unsigned long now; |
| 89 | #endif |
| 90 | midEntry->mid_state = MID_FREE; |
| 91 | atomic_dec(&midCount); |
| 92 | if (midEntry->large_buf) |
| 93 | cifs_buf_release(midEntry->resp_buf); |
| 94 | else |
| 95 | cifs_small_buf_release(midEntry->resp_buf); |
| 96 | #ifdef CONFIG_CIFS_STATS2 |
| 97 | now = jiffies; |
| 98 | /* commands taking longer than one second are indications that |
| 99 | something is wrong, unless it is quite a slow link or server */ |
| 100 | if ((now - midEntry->when_alloc) > HZ) { |
| 101 | if ((cifsFYI & CIFS_TIMER) && (midEntry->command != command)) { |
| 102 | pr_debug(" CIFS slow rsp: cmd %d mid %llu", |
| 103 | midEntry->command, midEntry->mid); |
| 104 | pr_info(" A: 0x%lx S: 0x%lx R: 0x%lx\n", |
| 105 | now - midEntry->when_alloc, |
| 106 | now - midEntry->when_sent, |
| 107 | now - midEntry->when_received); |
| 108 | } |
| 109 | } |
| 110 | #endif |
| 111 | mempool_free(midEntry, cifs_mid_poolp); |
| 112 | } |
| 113 | |
| 114 | void |
| 115 | cifs_delete_mid(struct mid_q_entry *mid) |
| 116 | { |
| 117 | spin_lock(&GlobalMid_Lock); |
| 118 | list_del(&mid->qhead); |
| 119 | spin_unlock(&GlobalMid_Lock); |
| 120 | |
| 121 | DeleteMidQEntry(mid); |
| 122 | } |
| 123 | |
| 124 | /* |
| 125 | * smb_send_kvec - send an array of kvecs to the server |
| 126 | * @server: Server to send the data to |
| 127 | * @smb_msg: Message to send |
| 128 | * @sent: amount of data sent on socket is stored here |
| 129 | * |
| 130 | * Our basic "send data to server" function. Should be called with srv_mutex |
| 131 | * held. The caller is responsible for handling the results. |
| 132 | */ |
| 133 | static int |
| 134 | smb_send_kvec(struct TCP_Server_Info *server, struct msghdr *smb_msg, |
| 135 | size_t *sent) |
| 136 | { |
| 137 | int rc = 0; |
| 138 | int retries = 0; |
| 139 | struct socket *ssocket = server->ssocket; |
| 140 | |
| 141 | *sent = 0; |
| 142 | |
| 143 | smb_msg->msg_name = (struct sockaddr *) &server->dstaddr; |
| 144 | smb_msg->msg_namelen = sizeof(struct sockaddr); |
| 145 | smb_msg->msg_control = NULL; |
| 146 | smb_msg->msg_controllen = 0; |
| 147 | if (server->noblocksnd) |
| 148 | smb_msg->msg_flags = MSG_DONTWAIT + MSG_NOSIGNAL; |
| 149 | else |
| 150 | smb_msg->msg_flags = MSG_NOSIGNAL; |
| 151 | |
| 152 | while (msg_data_left(smb_msg)) { |
| 153 | /* |
| 154 | * If blocking send, we try 3 times, since each can block |
| 155 | * for 5 seconds. For nonblocking we have to try more |
| 156 | * but wait increasing amounts of time allowing time for |
| 157 | * socket to clear. The overall time we wait in either |
| 158 | * case to send on the socket is about 15 seconds. |
| 159 | * Similarly we wait for 15 seconds for a response from |
| 160 | * the server in SendReceive[2] for the server to send |
| 161 | * a response back for most types of requests (except |
| 162 | * SMB Write past end of file which can be slow, and |
| 163 | * blocking lock operations). NFS waits slightly longer |
| 164 | * than CIFS, but this can make it take longer for |
| 165 | * nonresponsive servers to be detected and 15 seconds |
| 166 | * is more than enough time for modern networks to |
| 167 | * send a packet. In most cases if we fail to send |
| 168 | * after the retries we will kill the socket and |
| 169 | * reconnect which may clear the network problem. |
| 170 | */ |
| 171 | rc = sock_sendmsg(ssocket, smb_msg); |
| 172 | if (rc == -EAGAIN) { |
| 173 | retries++; |
| 174 | if (retries >= 14 || |
| 175 | (!server->noblocksnd && (retries > 2))) { |
| 176 | cifs_dbg(VFS, "sends on sock %p stuck for 15 seconds\n", |
| 177 | ssocket); |
| 178 | return -EAGAIN; |
| 179 | } |
| 180 | msleep(1 << retries); |
| 181 | continue; |
| 182 | } |
| 183 | |
| 184 | if (rc < 0) |
| 185 | return rc; |
| 186 | |
| 187 | if (rc == 0) { |
| 188 | /* should never happen, letting socket clear before |
| 189 | retrying is our only obvious option here */ |
| 190 | cifs_dbg(VFS, "tcp sent no data\n"); |
| 191 | msleep(500); |
| 192 | continue; |
| 193 | } |
| 194 | |
| 195 | /* send was at least partially successful */ |
| 196 | *sent += rc; |
| 197 | retries = 0; /* in case we get ENOSPC on the next send */ |
| 198 | } |
| 199 | return 0; |
| 200 | } |
| 201 | |
| 202 | static unsigned long |
| 203 | rqst_len(struct smb_rqst *rqst) |
| 204 | { |
| 205 | unsigned int i; |
| 206 | struct kvec *iov = rqst->rq_iov; |
| 207 | unsigned long buflen = 0; |
| 208 | |
| 209 | /* total up iov array first */ |
| 210 | for (i = 0; i < rqst->rq_nvec; i++) |
| 211 | buflen += iov[i].iov_len; |
| 212 | |
| 213 | /* add in the page array if there is one */ |
| 214 | if (rqst->rq_npages) { |
| 215 | buflen += rqst->rq_pagesz * (rqst->rq_npages - 1); |
| 216 | buflen += rqst->rq_tailsz; |
| 217 | } |
| 218 | |
| 219 | return buflen; |
| 220 | } |
| 221 | |
| 222 | static int |
| 223 | smb_send_rqst(struct TCP_Server_Info *server, struct smb_rqst *rqst) |
| 224 | { |
| 225 | int rc; |
| 226 | struct kvec *iov = rqst->rq_iov; |
| 227 | int n_vec = rqst->rq_nvec; |
| 228 | unsigned int smb_buf_length = get_rfc1002_length(iov[0].iov_base); |
| 229 | unsigned long send_length; |
| 230 | unsigned int i; |
| 231 | size_t total_len = 0, sent, size; |
| 232 | struct socket *ssocket = server->ssocket; |
| 233 | struct msghdr smb_msg; |
| 234 | int val = 1; |
| 235 | |
| 236 | if (ssocket == NULL) |
| 237 | return -ENOTSOCK; |
| 238 | |
| 239 | /* sanity check send length */ |
| 240 | send_length = rqst_len(rqst); |
| 241 | if (send_length != smb_buf_length + 4) { |
| 242 | WARN(1, "Send length mismatch(send_length=%lu smb_buf_length=%u)\n", |
| 243 | send_length, smb_buf_length); |
| 244 | return -EIO; |
| 245 | } |
| 246 | |
| 247 | cifs_dbg(FYI, "Sending smb: smb_len=%u\n", smb_buf_length); |
| 248 | dump_smb(iov[0].iov_base, iov[0].iov_len); |
| 249 | |
| 250 | /* cork the socket */ |
| 251 | kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK, |
| 252 | (char *)&val, sizeof(val)); |
| 253 | |
| 254 | size = 0; |
| 255 | for (i = 0; i < n_vec; i++) |
| 256 | size += iov[i].iov_len; |
| 257 | |
| 258 | iov_iter_kvec(&smb_msg.msg_iter, WRITE | ITER_KVEC, iov, n_vec, size); |
| 259 | |
| 260 | rc = smb_send_kvec(server, &smb_msg, &sent); |
| 261 | if (rc < 0) |
| 262 | goto uncork; |
| 263 | |
| 264 | total_len += sent; |
| 265 | |
| 266 | /* now walk the page array and send each page in it */ |
| 267 | for (i = 0; i < rqst->rq_npages; i++) { |
| 268 | size_t len = i == rqst->rq_npages - 1 |
| 269 | ? rqst->rq_tailsz |
| 270 | : rqst->rq_pagesz; |
| 271 | struct bio_vec bvec = { |
| 272 | .bv_page = rqst->rq_pages[i], |
| 273 | .bv_len = len |
| 274 | }; |
| 275 | iov_iter_bvec(&smb_msg.msg_iter, WRITE | ITER_BVEC, |
| 276 | &bvec, 1, len); |
| 277 | rc = smb_send_kvec(server, &smb_msg, &sent); |
| 278 | if (rc < 0) |
| 279 | break; |
| 280 | |
| 281 | total_len += sent; |
| 282 | } |
| 283 | |
| 284 | uncork: |
| 285 | /* uncork it */ |
| 286 | val = 0; |
| 287 | kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK, |
| 288 | (char *)&val, sizeof(val)); |
| 289 | |
| 290 | if ((total_len > 0) && (total_len != smb_buf_length + 4)) { |
| 291 | cifs_dbg(FYI, "partial send (wanted=%u sent=%zu): terminating session\n", |
| 292 | smb_buf_length + 4, total_len); |
| 293 | /* |
| 294 | * If we have only sent part of an SMB then the next SMB could |
| 295 | * be taken as the remainder of this one. We need to kill the |
| 296 | * socket so the server throws away the partial SMB |
| 297 | */ |
| 298 | server->tcpStatus = CifsNeedReconnect; |
| 299 | } |
| 300 | |
| 301 | if (rc < 0 && rc != -EINTR) |
| 302 | cifs_dbg(VFS, "Error %d sending data on socket to server\n", |
| 303 | rc); |
| 304 | else |
| 305 | rc = 0; |
| 306 | |
| 307 | return rc; |
| 308 | } |
| 309 | |
| 310 | static int |
| 311 | smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec) |
| 312 | { |
| 313 | struct smb_rqst rqst = { .rq_iov = iov, |
| 314 | .rq_nvec = n_vec }; |
| 315 | |
| 316 | return smb_send_rqst(server, &rqst); |
| 317 | } |
| 318 | |
| 319 | int |
| 320 | smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer, |
| 321 | unsigned int smb_buf_length) |
| 322 | { |
| 323 | struct kvec iov; |
| 324 | |
| 325 | iov.iov_base = smb_buffer; |
| 326 | iov.iov_len = smb_buf_length + 4; |
| 327 | |
| 328 | return smb_sendv(server, &iov, 1); |
| 329 | } |
| 330 | |
| 331 | static int |
| 332 | wait_for_free_credits(struct TCP_Server_Info *server, const int timeout, |
| 333 | int *credits) |
| 334 | { |
| 335 | int rc; |
| 336 | |
| 337 | spin_lock(&server->req_lock); |
| 338 | if (timeout == CIFS_ASYNC_OP) { |
| 339 | /* oplock breaks must not be held up */ |
| 340 | server->in_flight++; |
| 341 | *credits -= 1; |
| 342 | spin_unlock(&server->req_lock); |
| 343 | return 0; |
| 344 | } |
| 345 | |
| 346 | while (1) { |
| 347 | if (*credits <= 0) { |
| 348 | spin_unlock(&server->req_lock); |
| 349 | cifs_num_waiters_inc(server); |
| 350 | rc = wait_event_killable(server->request_q, |
| 351 | has_credits(server, credits)); |
| 352 | cifs_num_waiters_dec(server); |
| 353 | if (rc) |
| 354 | return rc; |
| 355 | spin_lock(&server->req_lock); |
| 356 | } else { |
| 357 | if (server->tcpStatus == CifsExiting) { |
| 358 | spin_unlock(&server->req_lock); |
| 359 | return -ENOENT; |
| 360 | } |
| 361 | |
| 362 | /* |
| 363 | * Can not count locking commands against total |
| 364 | * as they are allowed to block on server. |
| 365 | */ |
| 366 | |
| 367 | /* update # of requests on the wire to server */ |
| 368 | if (timeout != CIFS_BLOCKING_OP) { |
| 369 | *credits -= 1; |
| 370 | server->in_flight++; |
| 371 | } |
| 372 | spin_unlock(&server->req_lock); |
| 373 | break; |
| 374 | } |
| 375 | } |
| 376 | return 0; |
| 377 | } |
| 378 | |
| 379 | static int |
| 380 | wait_for_free_request(struct TCP_Server_Info *server, const int timeout, |
| 381 | const int optype) |
| 382 | { |
| 383 | int *val; |
| 384 | |
| 385 | val = server->ops->get_credits_field(server, optype); |
| 386 | /* Since an echo is already inflight, no need to wait to send another */ |
| 387 | if (*val <= 0 && optype == CIFS_ECHO_OP) |
| 388 | return -EAGAIN; |
| 389 | return wait_for_free_credits(server, timeout, val); |
| 390 | } |
| 391 | |
| 392 | int |
| 393 | cifs_wait_mtu_credits(struct TCP_Server_Info *server, unsigned int size, |
| 394 | unsigned int *num, unsigned int *credits) |
| 395 | { |
| 396 | *num = size; |
| 397 | *credits = 0; |
| 398 | return 0; |
| 399 | } |
| 400 | |
| 401 | static int allocate_mid(struct cifs_ses *ses, struct smb_hdr *in_buf, |
| 402 | struct mid_q_entry **ppmidQ) |
| 403 | { |
| 404 | if (ses->server->tcpStatus == CifsExiting) { |
| 405 | return -ENOENT; |
| 406 | } |
| 407 | |
| 408 | if (ses->server->tcpStatus == CifsNeedReconnect) { |
| 409 | cifs_dbg(FYI, "tcp session dead - return to caller to retry\n"); |
| 410 | return -EAGAIN; |
| 411 | } |
| 412 | |
| 413 | if (ses->status == CifsNew) { |
| 414 | if ((in_buf->Command != SMB_COM_SESSION_SETUP_ANDX) && |
| 415 | (in_buf->Command != SMB_COM_NEGOTIATE)) |
| 416 | return -EAGAIN; |
| 417 | /* else ok - we are setting up session */ |
| 418 | } |
| 419 | |
| 420 | if (ses->status == CifsExiting) { |
| 421 | /* check if SMB session is bad because we are setting it up */ |
| 422 | if (in_buf->Command != SMB_COM_LOGOFF_ANDX) |
| 423 | return -EAGAIN; |
| 424 | /* else ok - we are shutting down session */ |
| 425 | } |
| 426 | |
| 427 | *ppmidQ = AllocMidQEntry(in_buf, ses->server); |
| 428 | if (*ppmidQ == NULL) |
| 429 | return -ENOMEM; |
| 430 | spin_lock(&GlobalMid_Lock); |
| 431 | list_add_tail(&(*ppmidQ)->qhead, &ses->server->pending_mid_q); |
| 432 | spin_unlock(&GlobalMid_Lock); |
| 433 | return 0; |
| 434 | } |
| 435 | |
| 436 | static int |
| 437 | wait_for_response(struct TCP_Server_Info *server, struct mid_q_entry *midQ) |
| 438 | { |
| 439 | int error; |
| 440 | |
| 441 | error = wait_event_freezekillable_unsafe(server->response_q, |
| 442 | midQ->mid_state != MID_REQUEST_SUBMITTED); |
| 443 | if (error < 0) |
| 444 | return -ERESTARTSYS; |
| 445 | |
| 446 | return 0; |
| 447 | } |
| 448 | |
| 449 | struct mid_q_entry * |
| 450 | cifs_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst) |
| 451 | { |
| 452 | int rc; |
| 453 | struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base; |
| 454 | struct mid_q_entry *mid; |
| 455 | |
| 456 | /* enable signing if server requires it */ |
| 457 | if (server->sign) |
| 458 | hdr->Flags2 |= SMBFLG2_SECURITY_SIGNATURE; |
| 459 | |
| 460 | mid = AllocMidQEntry(hdr, server); |
| 461 | if (mid == NULL) |
| 462 | return ERR_PTR(-ENOMEM); |
| 463 | |
| 464 | rc = cifs_sign_rqst(rqst, server, &mid->sequence_number); |
| 465 | if (rc) { |
| 466 | DeleteMidQEntry(mid); |
| 467 | return ERR_PTR(rc); |
| 468 | } |
| 469 | |
| 470 | return mid; |
| 471 | } |
| 472 | |
| 473 | /* |
| 474 | * Send a SMB request and set the callback function in the mid to handle |
| 475 | * the result. Caller is responsible for dealing with timeouts. |
| 476 | */ |
| 477 | int |
| 478 | cifs_call_async(struct TCP_Server_Info *server, struct smb_rqst *rqst, |
| 479 | mid_receive_t *receive, mid_callback_t *callback, |
| 480 | void *cbdata, const int flags) |
| 481 | { |
| 482 | int rc, timeout, optype; |
| 483 | struct mid_q_entry *mid; |
| 484 | unsigned int credits = 0; |
| 485 | |
| 486 | timeout = flags & CIFS_TIMEOUT_MASK; |
| 487 | optype = flags & CIFS_OP_MASK; |
| 488 | |
| 489 | if ((flags & CIFS_HAS_CREDITS) == 0) { |
| 490 | rc = wait_for_free_request(server, timeout, optype); |
| 491 | if (rc) |
| 492 | return rc; |
| 493 | credits = 1; |
| 494 | } |
| 495 | |
| 496 | mutex_lock(&server->srv_mutex); |
| 497 | mid = server->ops->setup_async_request(server, rqst); |
| 498 | if (IS_ERR(mid)) { |
| 499 | mutex_unlock(&server->srv_mutex); |
| 500 | add_credits_and_wake_if(server, credits, optype); |
| 501 | return PTR_ERR(mid); |
| 502 | } |
| 503 | |
| 504 | mid->receive = receive; |
| 505 | mid->callback = callback; |
| 506 | mid->callback_data = cbdata; |
| 507 | mid->mid_state = MID_REQUEST_SUBMITTED; |
| 508 | |
| 509 | /* put it on the pending_mid_q */ |
| 510 | spin_lock(&GlobalMid_Lock); |
| 511 | list_add_tail(&mid->qhead, &server->pending_mid_q); |
| 512 | spin_unlock(&GlobalMid_Lock); |
| 513 | |
| 514 | |
| 515 | cifs_in_send_inc(server); |
| 516 | rc = smb_send_rqst(server, rqst); |
| 517 | cifs_in_send_dec(server); |
| 518 | cifs_save_when_sent(mid); |
| 519 | |
| 520 | if (rc < 0) { |
| 521 | server->sequence_number -= 2; |
| 522 | cifs_delete_mid(mid); |
| 523 | } |
| 524 | |
| 525 | mutex_unlock(&server->srv_mutex); |
| 526 | |
| 527 | if (rc == 0) |
| 528 | return 0; |
| 529 | |
| 530 | add_credits_and_wake_if(server, credits, optype); |
| 531 | return rc; |
| 532 | } |
| 533 | |
| 534 | /* |
| 535 | * |
| 536 | * Send an SMB Request. No response info (other than return code) |
| 537 | * needs to be parsed. |
| 538 | * |
| 539 | * flags indicate the type of request buffer and how long to wait |
| 540 | * and whether to log NT STATUS code (error) before mapping it to POSIX error |
| 541 | * |
| 542 | */ |
| 543 | int |
| 544 | SendReceiveNoRsp(const unsigned int xid, struct cifs_ses *ses, |
| 545 | char *in_buf, int flags) |
| 546 | { |
| 547 | int rc; |
| 548 | struct kvec iov[1]; |
| 549 | int resp_buf_type; |
| 550 | |
| 551 | iov[0].iov_base = in_buf; |
| 552 | iov[0].iov_len = get_rfc1002_length(in_buf) + 4; |
| 553 | flags |= CIFS_NO_RESP; |
| 554 | rc = SendReceive2(xid, ses, iov, 1, &resp_buf_type, flags); |
| 555 | cifs_dbg(NOISY, "SendRcvNoRsp flags %d rc %d\n", flags, rc); |
| 556 | |
| 557 | return rc; |
| 558 | } |
| 559 | |
| 560 | static int |
| 561 | cifs_sync_mid_result(struct mid_q_entry *mid, struct TCP_Server_Info *server) |
| 562 | { |
| 563 | int rc = 0; |
| 564 | |
| 565 | cifs_dbg(FYI, "%s: cmd=%d mid=%llu state=%d\n", |
| 566 | __func__, le16_to_cpu(mid->command), mid->mid, mid->mid_state); |
| 567 | |
| 568 | spin_lock(&GlobalMid_Lock); |
| 569 | switch (mid->mid_state) { |
| 570 | case MID_RESPONSE_RECEIVED: |
| 571 | spin_unlock(&GlobalMid_Lock); |
| 572 | return rc; |
| 573 | case MID_RETRY_NEEDED: |
| 574 | rc = -EAGAIN; |
| 575 | break; |
| 576 | case MID_RESPONSE_MALFORMED: |
| 577 | rc = -EIO; |
| 578 | break; |
| 579 | case MID_SHUTDOWN: |
| 580 | rc = -EHOSTDOWN; |
| 581 | break; |
| 582 | default: |
| 583 | list_del_init(&mid->qhead); |
| 584 | cifs_dbg(VFS, "%s: invalid mid state mid=%llu state=%d\n", |
| 585 | __func__, mid->mid, mid->mid_state); |
| 586 | rc = -EIO; |
| 587 | } |
| 588 | spin_unlock(&GlobalMid_Lock); |
| 589 | |
| 590 | mutex_lock(&server->srv_mutex); |
| 591 | DeleteMidQEntry(mid); |
| 592 | mutex_unlock(&server->srv_mutex); |
| 593 | return rc; |
| 594 | } |
| 595 | |
| 596 | static inline int |
| 597 | send_cancel(struct TCP_Server_Info *server, void *buf, struct mid_q_entry *mid) |
| 598 | { |
| 599 | return server->ops->send_cancel ? |
| 600 | server->ops->send_cancel(server, buf, mid) : 0; |
| 601 | } |
| 602 | |
| 603 | int |
| 604 | cifs_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server, |
| 605 | bool log_error) |
| 606 | { |
| 607 | unsigned int len = get_rfc1002_length(mid->resp_buf) + 4; |
| 608 | |
| 609 | dump_smb(mid->resp_buf, min_t(u32, 92, len)); |
| 610 | |
| 611 | /* convert the length into a more usable form */ |
| 612 | if (server->sign) { |
| 613 | struct kvec iov; |
| 614 | int rc = 0; |
| 615 | struct smb_rqst rqst = { .rq_iov = &iov, |
| 616 | .rq_nvec = 1 }; |
| 617 | |
| 618 | iov.iov_base = mid->resp_buf; |
| 619 | iov.iov_len = len; |
| 620 | /* FIXME: add code to kill session */ |
| 621 | rc = cifs_verify_signature(&rqst, server, |
| 622 | mid->sequence_number); |
| 623 | if (rc) |
| 624 | cifs_dbg(VFS, "SMB signature verification returned error = %d\n", |
| 625 | rc); |
| 626 | } |
| 627 | |
| 628 | /* BB special case reconnect tid and uid here? */ |
| 629 | return map_smb_to_linux_error(mid->resp_buf, log_error); |
| 630 | } |
| 631 | |
| 632 | struct mid_q_entry * |
| 633 | cifs_setup_request(struct cifs_ses *ses, struct smb_rqst *rqst) |
| 634 | { |
| 635 | int rc; |
| 636 | struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base; |
| 637 | struct mid_q_entry *mid; |
| 638 | |
| 639 | rc = allocate_mid(ses, hdr, &mid); |
| 640 | if (rc) |
| 641 | return ERR_PTR(rc); |
| 642 | rc = cifs_sign_rqst(rqst, ses->server, &mid->sequence_number); |
| 643 | if (rc) { |
| 644 | cifs_delete_mid(mid); |
| 645 | return ERR_PTR(rc); |
| 646 | } |
| 647 | return mid; |
| 648 | } |
| 649 | |
| 650 | int |
| 651 | SendReceive2(const unsigned int xid, struct cifs_ses *ses, |
| 652 | struct kvec *iov, int n_vec, int *resp_buf_type /* ret */, |
| 653 | const int flags) |
| 654 | { |
| 655 | int rc = 0; |
| 656 | int timeout, optype; |
| 657 | struct mid_q_entry *midQ; |
| 658 | char *buf = iov[0].iov_base; |
| 659 | unsigned int credits = 1; |
| 660 | struct smb_rqst rqst = { .rq_iov = iov, |
| 661 | .rq_nvec = n_vec }; |
| 662 | |
| 663 | timeout = flags & CIFS_TIMEOUT_MASK; |
| 664 | optype = flags & CIFS_OP_MASK; |
| 665 | |
| 666 | *resp_buf_type = CIFS_NO_BUFFER; /* no response buf yet */ |
| 667 | |
| 668 | if ((ses == NULL) || (ses->server == NULL)) { |
| 669 | cifs_small_buf_release(buf); |
| 670 | cifs_dbg(VFS, "Null session\n"); |
| 671 | return -EIO; |
| 672 | } |
| 673 | |
| 674 | if (ses->server->tcpStatus == CifsExiting) { |
| 675 | cifs_small_buf_release(buf); |
| 676 | return -ENOENT; |
| 677 | } |
| 678 | |
| 679 | /* |
| 680 | * Ensure that we do not send more than 50 overlapping requests |
| 681 | * to the same server. We may make this configurable later or |
| 682 | * use ses->maxReq. |
| 683 | */ |
| 684 | |
| 685 | rc = wait_for_free_request(ses->server, timeout, optype); |
| 686 | if (rc) { |
| 687 | cifs_small_buf_release(buf); |
| 688 | return rc; |
| 689 | } |
| 690 | |
| 691 | /* |
| 692 | * Make sure that we sign in the same order that we send on this socket |
| 693 | * and avoid races inside tcp sendmsg code that could cause corruption |
| 694 | * of smb data. |
| 695 | */ |
| 696 | |
| 697 | mutex_lock(&ses->server->srv_mutex); |
| 698 | |
| 699 | midQ = ses->server->ops->setup_request(ses, &rqst); |
| 700 | if (IS_ERR(midQ)) { |
| 701 | mutex_unlock(&ses->server->srv_mutex); |
| 702 | cifs_small_buf_release(buf); |
| 703 | /* Update # of requests on wire to server */ |
| 704 | add_credits(ses->server, 1, optype); |
| 705 | return PTR_ERR(midQ); |
| 706 | } |
| 707 | |
| 708 | midQ->mid_state = MID_REQUEST_SUBMITTED; |
| 709 | cifs_in_send_inc(ses->server); |
| 710 | rc = smb_sendv(ses->server, iov, n_vec); |
| 711 | cifs_in_send_dec(ses->server); |
| 712 | cifs_save_when_sent(midQ); |
| 713 | |
| 714 | if (rc < 0) |
| 715 | ses->server->sequence_number -= 2; |
| 716 | mutex_unlock(&ses->server->srv_mutex); |
| 717 | |
| 718 | if (rc < 0) { |
| 719 | cifs_small_buf_release(buf); |
| 720 | goto out; |
| 721 | } |
| 722 | |
| 723 | if (timeout == CIFS_ASYNC_OP) { |
| 724 | cifs_small_buf_release(buf); |
| 725 | goto out; |
| 726 | } |
| 727 | |
| 728 | rc = wait_for_response(ses->server, midQ); |
| 729 | if (rc != 0) { |
| 730 | send_cancel(ses->server, buf, midQ); |
| 731 | spin_lock(&GlobalMid_Lock); |
| 732 | if (midQ->mid_state == MID_REQUEST_SUBMITTED) { |
| 733 | midQ->callback = DeleteMidQEntry; |
| 734 | spin_unlock(&GlobalMid_Lock); |
| 735 | cifs_small_buf_release(buf); |
| 736 | add_credits(ses->server, 1, optype); |
| 737 | return rc; |
| 738 | } |
| 739 | spin_unlock(&GlobalMid_Lock); |
| 740 | } |
| 741 | |
| 742 | cifs_small_buf_release(buf); |
| 743 | |
| 744 | rc = cifs_sync_mid_result(midQ, ses->server); |
| 745 | if (rc != 0) { |
| 746 | add_credits(ses->server, 1, optype); |
| 747 | return rc; |
| 748 | } |
| 749 | |
| 750 | if (!midQ->resp_buf || midQ->mid_state != MID_RESPONSE_RECEIVED) { |
| 751 | rc = -EIO; |
| 752 | cifs_dbg(FYI, "Bad MID state?\n"); |
| 753 | goto out; |
| 754 | } |
| 755 | |
| 756 | buf = (char *)midQ->resp_buf; |
| 757 | iov[0].iov_base = buf; |
| 758 | iov[0].iov_len = get_rfc1002_length(buf) + 4; |
| 759 | if (midQ->large_buf) |
| 760 | *resp_buf_type = CIFS_LARGE_BUFFER; |
| 761 | else |
| 762 | *resp_buf_type = CIFS_SMALL_BUFFER; |
| 763 | |
| 764 | credits = ses->server->ops->get_credits(midQ); |
| 765 | |
| 766 | rc = ses->server->ops->check_receive(midQ, ses->server, |
| 767 | flags & CIFS_LOG_ERROR); |
| 768 | |
| 769 | /* mark it so buf will not be freed by cifs_delete_mid */ |
| 770 | if ((flags & CIFS_NO_RESP) == 0) |
| 771 | midQ->resp_buf = NULL; |
| 772 | out: |
| 773 | cifs_delete_mid(midQ); |
| 774 | add_credits(ses->server, credits, optype); |
| 775 | |
| 776 | return rc; |
| 777 | } |
| 778 | |
| 779 | int |
| 780 | SendReceive(const unsigned int xid, struct cifs_ses *ses, |
| 781 | struct smb_hdr *in_buf, struct smb_hdr *out_buf, |
| 782 | int *pbytes_returned, const int timeout) |
| 783 | { |
| 784 | int rc = 0; |
| 785 | struct mid_q_entry *midQ; |
| 786 | |
| 787 | if (ses == NULL) { |
| 788 | cifs_dbg(VFS, "Null smb session\n"); |
| 789 | return -EIO; |
| 790 | } |
| 791 | if (ses->server == NULL) { |
| 792 | cifs_dbg(VFS, "Null tcp session\n"); |
| 793 | return -EIO; |
| 794 | } |
| 795 | |
| 796 | if (ses->server->tcpStatus == CifsExiting) |
| 797 | return -ENOENT; |
| 798 | |
| 799 | /* Ensure that we do not send more than 50 overlapping requests |
| 800 | to the same server. We may make this configurable later or |
| 801 | use ses->maxReq */ |
| 802 | |
| 803 | if (be32_to_cpu(in_buf->smb_buf_length) > CIFSMaxBufSize + |
| 804 | MAX_CIFS_HDR_SIZE - 4) { |
| 805 | cifs_dbg(VFS, "Illegal length, greater than maximum frame, %d\n", |
| 806 | be32_to_cpu(in_buf->smb_buf_length)); |
| 807 | return -EIO; |
| 808 | } |
| 809 | |
| 810 | rc = wait_for_free_request(ses->server, timeout, 0); |
| 811 | if (rc) |
| 812 | return rc; |
| 813 | |
| 814 | /* make sure that we sign in the same order that we send on this socket |
| 815 | and avoid races inside tcp sendmsg code that could cause corruption |
| 816 | of smb data */ |
| 817 | |
| 818 | mutex_lock(&ses->server->srv_mutex); |
| 819 | |
| 820 | rc = allocate_mid(ses, in_buf, &midQ); |
| 821 | if (rc) { |
| 822 | mutex_unlock(&ses->server->srv_mutex); |
| 823 | /* Update # of requests on wire to server */ |
| 824 | add_credits(ses->server, 1, 0); |
| 825 | return rc; |
| 826 | } |
| 827 | |
| 828 | rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number); |
| 829 | if (rc) { |
| 830 | mutex_unlock(&ses->server->srv_mutex); |
| 831 | goto out; |
| 832 | } |
| 833 | |
| 834 | midQ->mid_state = MID_REQUEST_SUBMITTED; |
| 835 | |
| 836 | cifs_in_send_inc(ses->server); |
| 837 | rc = smb_send(ses->server, in_buf, be32_to_cpu(in_buf->smb_buf_length)); |
| 838 | cifs_in_send_dec(ses->server); |
| 839 | cifs_save_when_sent(midQ); |
| 840 | |
| 841 | if (rc < 0) |
| 842 | ses->server->sequence_number -= 2; |
| 843 | |
| 844 | mutex_unlock(&ses->server->srv_mutex); |
| 845 | |
| 846 | if (rc < 0) |
| 847 | goto out; |
| 848 | |
| 849 | if (timeout == CIFS_ASYNC_OP) |
| 850 | goto out; |
| 851 | |
| 852 | rc = wait_for_response(ses->server, midQ); |
| 853 | if (rc != 0) { |
| 854 | send_cancel(ses->server, in_buf, midQ); |
| 855 | spin_lock(&GlobalMid_Lock); |
| 856 | if (midQ->mid_state == MID_REQUEST_SUBMITTED) { |
| 857 | /* no longer considered to be "in-flight" */ |
| 858 | midQ->callback = DeleteMidQEntry; |
| 859 | spin_unlock(&GlobalMid_Lock); |
| 860 | add_credits(ses->server, 1, 0); |
| 861 | return rc; |
| 862 | } |
| 863 | spin_unlock(&GlobalMid_Lock); |
| 864 | } |
| 865 | |
| 866 | rc = cifs_sync_mid_result(midQ, ses->server); |
| 867 | if (rc != 0) { |
| 868 | add_credits(ses->server, 1, 0); |
| 869 | return rc; |
| 870 | } |
| 871 | |
| 872 | if (!midQ->resp_buf || !out_buf || |
| 873 | midQ->mid_state != MID_RESPONSE_RECEIVED) { |
| 874 | rc = -EIO; |
| 875 | cifs_dbg(VFS, "Bad MID state?\n"); |
| 876 | goto out; |
| 877 | } |
| 878 | |
| 879 | *pbytes_returned = get_rfc1002_length(midQ->resp_buf); |
| 880 | memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4); |
| 881 | rc = cifs_check_receive(midQ, ses->server, 0); |
| 882 | out: |
| 883 | cifs_delete_mid(midQ); |
| 884 | add_credits(ses->server, 1, 0); |
| 885 | |
| 886 | return rc; |
| 887 | } |
| 888 | |
| 889 | /* We send a LOCKINGX_CANCEL_LOCK to cause the Windows |
| 890 | blocking lock to return. */ |
| 891 | |
| 892 | static int |
| 893 | send_lock_cancel(const unsigned int xid, struct cifs_tcon *tcon, |
| 894 | struct smb_hdr *in_buf, |
| 895 | struct smb_hdr *out_buf) |
| 896 | { |
| 897 | int bytes_returned; |
| 898 | struct cifs_ses *ses = tcon->ses; |
| 899 | LOCK_REQ *pSMB = (LOCK_REQ *)in_buf; |
| 900 | |
| 901 | /* We just modify the current in_buf to change |
| 902 | the type of lock from LOCKING_ANDX_SHARED_LOCK |
| 903 | or LOCKING_ANDX_EXCLUSIVE_LOCK to |
| 904 | LOCKING_ANDX_CANCEL_LOCK. */ |
| 905 | |
| 906 | pSMB->LockType = LOCKING_ANDX_CANCEL_LOCK|LOCKING_ANDX_LARGE_FILES; |
| 907 | pSMB->Timeout = 0; |
| 908 | pSMB->hdr.Mid = get_next_mid(ses->server); |
| 909 | |
| 910 | return SendReceive(xid, ses, in_buf, out_buf, |
| 911 | &bytes_returned, 0); |
| 912 | } |
| 913 | |
| 914 | int |
| 915 | SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon, |
| 916 | struct smb_hdr *in_buf, struct smb_hdr *out_buf, |
| 917 | int *pbytes_returned) |
| 918 | { |
| 919 | int rc = 0; |
| 920 | int rstart = 0; |
| 921 | struct mid_q_entry *midQ; |
| 922 | struct cifs_ses *ses; |
| 923 | |
| 924 | if (tcon == NULL || tcon->ses == NULL) { |
| 925 | cifs_dbg(VFS, "Null smb session\n"); |
| 926 | return -EIO; |
| 927 | } |
| 928 | ses = tcon->ses; |
| 929 | |
| 930 | if (ses->server == NULL) { |
| 931 | cifs_dbg(VFS, "Null tcp session\n"); |
| 932 | return -EIO; |
| 933 | } |
| 934 | |
| 935 | if (ses->server->tcpStatus == CifsExiting) |
| 936 | return -ENOENT; |
| 937 | |
| 938 | /* Ensure that we do not send more than 50 overlapping requests |
| 939 | to the same server. We may make this configurable later or |
| 940 | use ses->maxReq */ |
| 941 | |
| 942 | if (be32_to_cpu(in_buf->smb_buf_length) > CIFSMaxBufSize + |
| 943 | MAX_CIFS_HDR_SIZE - 4) { |
| 944 | cifs_dbg(VFS, "Illegal length, greater than maximum frame, %d\n", |
| 945 | be32_to_cpu(in_buf->smb_buf_length)); |
| 946 | return -EIO; |
| 947 | } |
| 948 | |
| 949 | rc = wait_for_free_request(ses->server, CIFS_BLOCKING_OP, 0); |
| 950 | if (rc) |
| 951 | return rc; |
| 952 | |
| 953 | /* make sure that we sign in the same order that we send on this socket |
| 954 | and avoid races inside tcp sendmsg code that could cause corruption |
| 955 | of smb data */ |
| 956 | |
| 957 | mutex_lock(&ses->server->srv_mutex); |
| 958 | |
| 959 | rc = allocate_mid(ses, in_buf, &midQ); |
| 960 | if (rc) { |
| 961 | mutex_unlock(&ses->server->srv_mutex); |
| 962 | return rc; |
| 963 | } |
| 964 | |
| 965 | rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number); |
| 966 | if (rc) { |
| 967 | cifs_delete_mid(midQ); |
| 968 | mutex_unlock(&ses->server->srv_mutex); |
| 969 | return rc; |
| 970 | } |
| 971 | |
| 972 | midQ->mid_state = MID_REQUEST_SUBMITTED; |
| 973 | cifs_in_send_inc(ses->server); |
| 974 | rc = smb_send(ses->server, in_buf, be32_to_cpu(in_buf->smb_buf_length)); |
| 975 | cifs_in_send_dec(ses->server); |
| 976 | cifs_save_when_sent(midQ); |
| 977 | |
| 978 | if (rc < 0) |
| 979 | ses->server->sequence_number -= 2; |
| 980 | |
| 981 | mutex_unlock(&ses->server->srv_mutex); |
| 982 | |
| 983 | if (rc < 0) { |
| 984 | cifs_delete_mid(midQ); |
| 985 | return rc; |
| 986 | } |
| 987 | |
| 988 | /* Wait for a reply - allow signals to interrupt. */ |
| 989 | rc = wait_event_interruptible(ses->server->response_q, |
| 990 | (!(midQ->mid_state == MID_REQUEST_SUBMITTED)) || |
| 991 | ((ses->server->tcpStatus != CifsGood) && |
| 992 | (ses->server->tcpStatus != CifsNew))); |
| 993 | |
| 994 | /* Were we interrupted by a signal ? */ |
| 995 | if ((rc == -ERESTARTSYS) && |
| 996 | (midQ->mid_state == MID_REQUEST_SUBMITTED) && |
| 997 | ((ses->server->tcpStatus == CifsGood) || |
| 998 | (ses->server->tcpStatus == CifsNew))) { |
| 999 | |
| 1000 | if (in_buf->Command == SMB_COM_TRANSACTION2) { |
| 1001 | /* POSIX lock. We send a NT_CANCEL SMB to cause the |
| 1002 | blocking lock to return. */ |
| 1003 | rc = send_cancel(ses->server, in_buf, midQ); |
| 1004 | if (rc) { |
| 1005 | cifs_delete_mid(midQ); |
| 1006 | return rc; |
| 1007 | } |
| 1008 | } else { |
| 1009 | /* Windows lock. We send a LOCKINGX_CANCEL_LOCK |
| 1010 | to cause the blocking lock to return. */ |
| 1011 | |
| 1012 | rc = send_lock_cancel(xid, tcon, in_buf, out_buf); |
| 1013 | |
| 1014 | /* If we get -ENOLCK back the lock may have |
| 1015 | already been removed. Don't exit in this case. */ |
| 1016 | if (rc && rc != -ENOLCK) { |
| 1017 | cifs_delete_mid(midQ); |
| 1018 | return rc; |
| 1019 | } |
| 1020 | } |
| 1021 | |
| 1022 | rc = wait_for_response(ses->server, midQ); |
| 1023 | if (rc) { |
| 1024 | send_cancel(ses->server, in_buf, midQ); |
| 1025 | spin_lock(&GlobalMid_Lock); |
| 1026 | if (midQ->mid_state == MID_REQUEST_SUBMITTED) { |
| 1027 | /* no longer considered to be "in-flight" */ |
| 1028 | midQ->callback = DeleteMidQEntry; |
| 1029 | spin_unlock(&GlobalMid_Lock); |
| 1030 | return rc; |
| 1031 | } |
| 1032 | spin_unlock(&GlobalMid_Lock); |
| 1033 | } |
| 1034 | |
| 1035 | /* We got the response - restart system call. */ |
| 1036 | rstart = 1; |
| 1037 | } |
| 1038 | |
| 1039 | rc = cifs_sync_mid_result(midQ, ses->server); |
| 1040 | if (rc != 0) |
| 1041 | return rc; |
| 1042 | |
| 1043 | /* rcvd frame is ok */ |
| 1044 | if (out_buf == NULL || midQ->mid_state != MID_RESPONSE_RECEIVED) { |
| 1045 | rc = -EIO; |
| 1046 | cifs_dbg(VFS, "Bad MID state?\n"); |
| 1047 | goto out; |
| 1048 | } |
| 1049 | |
| 1050 | *pbytes_returned = get_rfc1002_length(midQ->resp_buf); |
| 1051 | memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4); |
| 1052 | rc = cifs_check_receive(midQ, ses->server, 0); |
| 1053 | out: |
| 1054 | cifs_delete_mid(midQ); |
| 1055 | if (rstart && rc == -EACCES) |
| 1056 | return -ERESTARTSYS; |
| 1057 | return rc; |
| 1058 | } |