David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 1 | /****************************************************************************** |
| 2 | ******************************************************************************* |
| 3 | ** |
| 4 | ** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. |
| 5 | ** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. |
| 6 | ** |
| 7 | ** This copyrighted material is made available to anyone wishing to use, |
| 8 | ** modify, copy, or redistribute it subject to the terms and conditions |
| 9 | ** of the GNU General Public License v.2. |
| 10 | ** |
| 11 | ******************************************************************************* |
| 12 | ******************************************************************************/ |
| 13 | |
| 14 | /* |
| 15 | * lowcomms.c |
| 16 | * |
| 17 | * This is the "low-level" comms layer. |
| 18 | * |
| 19 | * It is responsible for sending/receiving messages |
| 20 | * from other nodes in the cluster. |
| 21 | * |
| 22 | * Cluster nodes are referred to by their nodeids. nodeids are |
| 23 | * simply 32 bit numbers to the locking module - if they need to |
| 24 | * be expanded for the cluster infrastructure then that is it's |
| 25 | * responsibility. It is this layer's |
| 26 | * responsibility to resolve these into IP address or |
| 27 | * whatever it needs for inter-node communication. |
| 28 | * |
| 29 | * The comms level is two kernel threads that deal mainly with |
| 30 | * the receiving of messages from other nodes and passing them |
| 31 | * up to the mid-level comms layer (which understands the |
| 32 | * message format) for execution by the locking core, and |
| 33 | * a send thread which does all the setting up of connections |
| 34 | * to remote nodes and the sending of data. Threads are not allowed |
| 35 | * to send their own data because it may cause them to wait in times |
| 36 | * of high load. Also, this way, the sending thread can collect together |
| 37 | * messages bound for one node and send them in one block. |
| 38 | * |
| 39 | * I don't see any problem with the recv thread executing the locking |
| 40 | * code on behalf of remote processes as the locking code is |
| 41 | * short, efficient and never (well, hardly ever) waits. |
| 42 | * |
| 43 | */ |
| 44 | |
| 45 | #include <asm/ioctls.h> |
| 46 | #include <net/sock.h> |
| 47 | #include <net/tcp.h> |
| 48 | #include <net/sctp/user.h> |
| 49 | #include <linux/pagemap.h> |
| 50 | #include <linux/socket.h> |
| 51 | #include <linux/idr.h> |
| 52 | |
| 53 | #include "dlm_internal.h" |
| 54 | #include "lowcomms.h" |
| 55 | #include "config.h" |
| 56 | #include "midcomms.h" |
| 57 | |
Steven Whitehouse | 47c96298 | 2006-05-25 17:43:14 -0400 | [diff] [blame] | 58 | static struct sockaddr_storage *dlm_local_addr[DLM_MAX_ADDR_COUNT]; |
| 59 | static int dlm_local_count; |
| 60 | static int dlm_local_nodeid; |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 61 | |
| 62 | /* One of these per connected node */ |
| 63 | |
| 64 | #define NI_INIT_PENDING 1 |
| 65 | #define NI_WRITE_PENDING 2 |
| 66 | |
| 67 | struct nodeinfo { |
| 68 | spinlock_t lock; |
| 69 | sctp_assoc_t assoc_id; |
| 70 | unsigned long flags; |
| 71 | struct list_head write_list; /* nodes with pending writes */ |
| 72 | struct list_head writequeue; /* outgoing writequeue_entries */ |
| 73 | spinlock_t writequeue_lock; |
| 74 | int nodeid; |
| 75 | }; |
| 76 | |
| 77 | static DEFINE_IDR(nodeinfo_idr); |
| 78 | static struct rw_semaphore nodeinfo_lock; |
| 79 | static int max_nodeid; |
| 80 | |
| 81 | struct cbuf { |
| 82 | unsigned base; |
| 83 | unsigned len; |
| 84 | unsigned mask; |
| 85 | }; |
| 86 | |
| 87 | /* Just the one of these, now. But this struct keeps |
| 88 | the connection-specific variables together */ |
| 89 | |
| 90 | #define CF_READ_PENDING 1 |
| 91 | |
| 92 | struct connection { |
| 93 | struct socket *sock; |
| 94 | unsigned long flags; |
| 95 | struct page *rx_page; |
| 96 | atomic_t waiting_requests; |
| 97 | struct cbuf cb; |
| 98 | int eagain_flag; |
| 99 | }; |
| 100 | |
| 101 | /* An entry waiting to be sent */ |
| 102 | |
| 103 | struct writequeue_entry { |
| 104 | struct list_head list; |
| 105 | struct page *page; |
| 106 | int offset; |
| 107 | int len; |
| 108 | int end; |
| 109 | int users; |
| 110 | struct nodeinfo *ni; |
| 111 | }; |
| 112 | |
| 113 | #define CBUF_ADD(cb, n) do { (cb)->len += n; } while(0) |
| 114 | #define CBUF_EMPTY(cb) ((cb)->len == 0) |
| 115 | #define CBUF_MAY_ADD(cb, n) (((cb)->len + (n)) < ((cb)->mask + 1)) |
| 116 | #define CBUF_DATA(cb) (((cb)->base + (cb)->len) & (cb)->mask) |
| 117 | |
| 118 | #define CBUF_INIT(cb, size) \ |
| 119 | do { \ |
| 120 | (cb)->base = (cb)->len = 0; \ |
| 121 | (cb)->mask = ((size)-1); \ |
| 122 | } while(0) |
| 123 | |
| 124 | #define CBUF_EAT(cb, n) \ |
| 125 | do { \ |
| 126 | (cb)->len -= (n); \ |
| 127 | (cb)->base += (n); \ |
| 128 | (cb)->base &= (cb)->mask; \ |
| 129 | } while(0) |
| 130 | |
| 131 | |
| 132 | /* List of nodes which have writes pending */ |
| 133 | static struct list_head write_nodes; |
| 134 | static spinlock_t write_nodes_lock; |
| 135 | |
| 136 | /* Maximum number of incoming messages to process before |
| 137 | * doing a schedule() |
| 138 | */ |
| 139 | #define MAX_RX_MSG_COUNT 25 |
| 140 | |
| 141 | /* Manage daemons */ |
| 142 | static struct task_struct *recv_task; |
| 143 | static struct task_struct *send_task; |
| 144 | static wait_queue_head_t lowcomms_recv_wait; |
| 145 | static atomic_t accepting; |
| 146 | |
| 147 | /* The SCTP connection */ |
| 148 | static struct connection sctp_con; |
| 149 | |
| 150 | |
| 151 | static int nodeid_to_addr(int nodeid, struct sockaddr *retaddr) |
| 152 | { |
| 153 | struct sockaddr_storage addr; |
| 154 | int error; |
| 155 | |
Steven Whitehouse | 47c96298 | 2006-05-25 17:43:14 -0400 | [diff] [blame] | 156 | if (!dlm_local_count) |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 157 | return -1; |
| 158 | |
| 159 | error = dlm_nodeid_to_addr(nodeid, &addr); |
| 160 | if (error) |
| 161 | return error; |
| 162 | |
Steven Whitehouse | 47c96298 | 2006-05-25 17:43:14 -0400 | [diff] [blame] | 163 | if (dlm_local_addr[0]->ss_family == AF_INET) { |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 164 | struct sockaddr_in *in4 = (struct sockaddr_in *) &addr; |
| 165 | struct sockaddr_in *ret4 = (struct sockaddr_in *) retaddr; |
| 166 | ret4->sin_addr.s_addr = in4->sin_addr.s_addr; |
| 167 | } else { |
| 168 | struct sockaddr_in6 *in6 = (struct sockaddr_in6 *) &addr; |
| 169 | struct sockaddr_in6 *ret6 = (struct sockaddr_in6 *) retaddr; |
| 170 | memcpy(&ret6->sin6_addr, &in6->sin6_addr, |
| 171 | sizeof(in6->sin6_addr)); |
| 172 | } |
| 173 | |
| 174 | return 0; |
| 175 | } |
| 176 | |
| 177 | static struct nodeinfo *nodeid2nodeinfo(int nodeid, int alloc) |
| 178 | { |
| 179 | struct nodeinfo *ni; |
| 180 | int r; |
| 181 | int n; |
| 182 | |
| 183 | down_read(&nodeinfo_lock); |
| 184 | ni = idr_find(&nodeinfo_idr, nodeid); |
| 185 | up_read(&nodeinfo_lock); |
| 186 | |
| 187 | if (!ni && alloc) { |
| 188 | down_write(&nodeinfo_lock); |
| 189 | |
| 190 | ni = idr_find(&nodeinfo_idr, nodeid); |
| 191 | if (ni) |
| 192 | goto out_up; |
| 193 | |
| 194 | r = idr_pre_get(&nodeinfo_idr, alloc); |
| 195 | if (!r) |
| 196 | goto out_up; |
| 197 | |
| 198 | ni = kmalloc(sizeof(struct nodeinfo), alloc); |
| 199 | if (!ni) |
| 200 | goto out_up; |
| 201 | |
| 202 | r = idr_get_new_above(&nodeinfo_idr, ni, nodeid, &n); |
| 203 | if (r) { |
| 204 | kfree(ni); |
| 205 | ni = NULL; |
| 206 | goto out_up; |
| 207 | } |
| 208 | if (n != nodeid) { |
| 209 | idr_remove(&nodeinfo_idr, n); |
| 210 | kfree(ni); |
| 211 | ni = NULL; |
| 212 | goto out_up; |
| 213 | } |
| 214 | memset(ni, 0, sizeof(struct nodeinfo)); |
| 215 | spin_lock_init(&ni->lock); |
| 216 | INIT_LIST_HEAD(&ni->writequeue); |
| 217 | spin_lock_init(&ni->writequeue_lock); |
| 218 | ni->nodeid = nodeid; |
| 219 | |
| 220 | if (nodeid > max_nodeid) |
| 221 | max_nodeid = nodeid; |
| 222 | out_up: |
| 223 | up_write(&nodeinfo_lock); |
| 224 | } |
| 225 | |
| 226 | return ni; |
| 227 | } |
| 228 | |
| 229 | /* Don't call this too often... */ |
| 230 | static struct nodeinfo *assoc2nodeinfo(sctp_assoc_t assoc) |
| 231 | { |
| 232 | int i; |
| 233 | struct nodeinfo *ni; |
| 234 | |
| 235 | for (i=1; i<=max_nodeid; i++) { |
| 236 | ni = nodeid2nodeinfo(i, 0); |
| 237 | if (ni && ni->assoc_id == assoc) |
| 238 | return ni; |
| 239 | } |
| 240 | return NULL; |
| 241 | } |
| 242 | |
| 243 | /* Data or notification available on socket */ |
| 244 | static void lowcomms_data_ready(struct sock *sk, int count_unused) |
| 245 | { |
| 246 | atomic_inc(&sctp_con.waiting_requests); |
| 247 | if (test_and_set_bit(CF_READ_PENDING, &sctp_con.flags)) |
| 248 | return; |
| 249 | |
| 250 | wake_up_interruptible(&lowcomms_recv_wait); |
| 251 | } |
| 252 | |
| 253 | |
| 254 | /* Add the port number to an IP6 or 4 sockaddr and return the address length. |
| 255 | Also padd out the struct with zeros to make comparisons meaningful */ |
| 256 | |
| 257 | static void make_sockaddr(struct sockaddr_storage *saddr, uint16_t port, |
| 258 | int *addr_len) |
| 259 | { |
| 260 | struct sockaddr_in *local4_addr; |
| 261 | struct sockaddr_in6 *local6_addr; |
| 262 | |
Steven Whitehouse | 47c96298 | 2006-05-25 17:43:14 -0400 | [diff] [blame] | 263 | if (!dlm_local_count) |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 264 | return; |
| 265 | |
| 266 | if (!port) { |
Steven Whitehouse | 47c96298 | 2006-05-25 17:43:14 -0400 | [diff] [blame] | 267 | if (dlm_local_addr[0]->ss_family == AF_INET) { |
| 268 | local4_addr = (struct sockaddr_in *)dlm_local_addr[0]; |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 269 | port = be16_to_cpu(local4_addr->sin_port); |
| 270 | } else { |
Steven Whitehouse | 47c96298 | 2006-05-25 17:43:14 -0400 | [diff] [blame] | 271 | local6_addr = (struct sockaddr_in6 *)dlm_local_addr[0]; |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 272 | port = be16_to_cpu(local6_addr->sin6_port); |
| 273 | } |
| 274 | } |
| 275 | |
Steven Whitehouse | 47c96298 | 2006-05-25 17:43:14 -0400 | [diff] [blame] | 276 | saddr->ss_family = dlm_local_addr[0]->ss_family; |
| 277 | if (dlm_local_addr[0]->ss_family == AF_INET) { |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 278 | struct sockaddr_in *in4_addr = (struct sockaddr_in *)saddr; |
| 279 | in4_addr->sin_port = cpu_to_be16(port); |
| 280 | memset(&in4_addr->sin_zero, 0, sizeof(in4_addr->sin_zero)); |
| 281 | memset(in4_addr+1, 0, sizeof(struct sockaddr_storage) - |
| 282 | sizeof(struct sockaddr_in)); |
| 283 | *addr_len = sizeof(struct sockaddr_in); |
| 284 | } else { |
| 285 | struct sockaddr_in6 *in6_addr = (struct sockaddr_in6 *)saddr; |
| 286 | in6_addr->sin6_port = cpu_to_be16(port); |
| 287 | memset(in6_addr+1, 0, sizeof(struct sockaddr_storage) - |
| 288 | sizeof(struct sockaddr_in6)); |
| 289 | *addr_len = sizeof(struct sockaddr_in6); |
| 290 | } |
| 291 | } |
| 292 | |
| 293 | /* Close the connection and tidy up */ |
| 294 | static void close_connection(void) |
| 295 | { |
| 296 | if (sctp_con.sock) { |
| 297 | sock_release(sctp_con.sock); |
| 298 | sctp_con.sock = NULL; |
| 299 | } |
| 300 | |
| 301 | if (sctp_con.rx_page) { |
| 302 | __free_page(sctp_con.rx_page); |
| 303 | sctp_con.rx_page = NULL; |
| 304 | } |
| 305 | } |
| 306 | |
| 307 | /* We only send shutdown messages to nodes that are not part of the cluster */ |
| 308 | static void send_shutdown(sctp_assoc_t associd) |
| 309 | { |
| 310 | static char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))]; |
| 311 | struct msghdr outmessage; |
| 312 | struct cmsghdr *cmsg; |
| 313 | struct sctp_sndrcvinfo *sinfo; |
| 314 | int ret; |
| 315 | |
| 316 | outmessage.msg_name = NULL; |
| 317 | outmessage.msg_namelen = 0; |
| 318 | outmessage.msg_control = outcmsg; |
| 319 | outmessage.msg_controllen = sizeof(outcmsg); |
| 320 | outmessage.msg_flags = MSG_EOR; |
| 321 | |
| 322 | cmsg = CMSG_FIRSTHDR(&outmessage); |
| 323 | cmsg->cmsg_level = IPPROTO_SCTP; |
| 324 | cmsg->cmsg_type = SCTP_SNDRCV; |
| 325 | cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo)); |
| 326 | outmessage.msg_controllen = cmsg->cmsg_len; |
| 327 | sinfo = (struct sctp_sndrcvinfo *)CMSG_DATA(cmsg); |
| 328 | memset(sinfo, 0x00, sizeof(struct sctp_sndrcvinfo)); |
| 329 | |
| 330 | sinfo->sinfo_flags |= MSG_EOF; |
| 331 | sinfo->sinfo_assoc_id = associd; |
| 332 | |
| 333 | ret = kernel_sendmsg(sctp_con.sock, &outmessage, NULL, 0, 0); |
| 334 | |
| 335 | if (ret != 0) |
| 336 | log_print("send EOF to node failed: %d", ret); |
| 337 | } |
| 338 | |
| 339 | |
| 340 | /* INIT failed but we don't know which node... |
| 341 | restart INIT on all pending nodes */ |
| 342 | static void init_failed(void) |
| 343 | { |
| 344 | int i; |
| 345 | struct nodeinfo *ni; |
| 346 | |
| 347 | for (i=1; i<=max_nodeid; i++) { |
| 348 | ni = nodeid2nodeinfo(i, 0); |
| 349 | if (!ni) |
| 350 | continue; |
| 351 | |
| 352 | if (test_and_clear_bit(NI_INIT_PENDING, &ni->flags)) { |
| 353 | ni->assoc_id = 0; |
| 354 | if (!test_and_set_bit(NI_WRITE_PENDING, &ni->flags)) { |
| 355 | spin_lock_bh(&write_nodes_lock); |
| 356 | list_add_tail(&ni->write_list, &write_nodes); |
| 357 | spin_unlock_bh(&write_nodes_lock); |
| 358 | } |
| 359 | } |
| 360 | } |
| 361 | wake_up_process(send_task); |
| 362 | } |
| 363 | |
| 364 | /* Something happened to an association */ |
| 365 | static void process_sctp_notification(struct msghdr *msg, char *buf) |
| 366 | { |
| 367 | union sctp_notification *sn = (union sctp_notification *)buf; |
| 368 | |
| 369 | if (sn->sn_header.sn_type == SCTP_ASSOC_CHANGE) { |
| 370 | switch (sn->sn_assoc_change.sac_state) { |
| 371 | |
| 372 | case SCTP_COMM_UP: |
| 373 | case SCTP_RESTART: |
| 374 | { |
| 375 | /* Check that the new node is in the lockspace */ |
| 376 | struct sctp_prim prim; |
| 377 | mm_segment_t fs; |
| 378 | int nodeid; |
| 379 | int prim_len, ret; |
| 380 | int addr_len; |
| 381 | struct nodeinfo *ni; |
| 382 | |
| 383 | /* This seems to happen when we received a connection |
| 384 | * too early... or something... anyway, it happens but |
| 385 | * we always seem to get a real message too, see |
| 386 | * receive_from_sock */ |
| 387 | |
| 388 | if ((int)sn->sn_assoc_change.sac_assoc_id <= 0) { |
| 389 | log_print("COMM_UP for invalid assoc ID %d", |
| 390 | (int)sn->sn_assoc_change.sac_assoc_id); |
| 391 | init_failed(); |
| 392 | return; |
| 393 | } |
| 394 | memset(&prim, 0, sizeof(struct sctp_prim)); |
| 395 | prim_len = sizeof(struct sctp_prim); |
| 396 | prim.ssp_assoc_id = sn->sn_assoc_change.sac_assoc_id; |
| 397 | |
| 398 | fs = get_fs(); |
| 399 | set_fs(get_ds()); |
| 400 | ret = sctp_con.sock->ops->getsockopt(sctp_con.sock, |
| 401 | IPPROTO_SCTP, SCTP_PRIMARY_ADDR, |
| 402 | (char*)&prim, &prim_len); |
| 403 | set_fs(fs); |
| 404 | if (ret < 0) { |
| 405 | struct nodeinfo *ni; |
| 406 | |
| 407 | log_print("getsockopt/sctp_primary_addr on " |
| 408 | "new assoc %d failed : %d", |
| 409 | (int)sn->sn_assoc_change.sac_assoc_id, ret); |
| 410 | |
| 411 | /* Retry INIT later */ |
| 412 | ni = assoc2nodeinfo(sn->sn_assoc_change.sac_assoc_id); |
| 413 | if (ni) |
| 414 | clear_bit(NI_INIT_PENDING, &ni->flags); |
| 415 | return; |
| 416 | } |
| 417 | make_sockaddr(&prim.ssp_addr, 0, &addr_len); |
| 418 | if (dlm_addr_to_nodeid(&prim.ssp_addr, &nodeid)) { |
| 419 | log_print("reject connect from unknown addr"); |
| 420 | send_shutdown(prim.ssp_assoc_id); |
| 421 | return; |
| 422 | } |
| 423 | |
| 424 | ni = nodeid2nodeinfo(nodeid, GFP_KERNEL); |
| 425 | if (!ni) |
| 426 | return; |
| 427 | |
| 428 | /* Save the assoc ID */ |
| 429 | spin_lock(&ni->lock); |
| 430 | ni->assoc_id = sn->sn_assoc_change.sac_assoc_id; |
| 431 | spin_unlock(&ni->lock); |
| 432 | |
| 433 | log_print("got new/restarted association %d nodeid %d", |
| 434 | (int)sn->sn_assoc_change.sac_assoc_id, nodeid); |
| 435 | |
| 436 | /* Send any pending writes */ |
| 437 | clear_bit(NI_INIT_PENDING, &ni->flags); |
| 438 | if (!test_and_set_bit(NI_WRITE_PENDING, &ni->flags)) { |
| 439 | spin_lock_bh(&write_nodes_lock); |
| 440 | list_add_tail(&ni->write_list, &write_nodes); |
| 441 | spin_unlock_bh(&write_nodes_lock); |
| 442 | } |
| 443 | wake_up_process(send_task); |
| 444 | } |
| 445 | break; |
| 446 | |
| 447 | case SCTP_COMM_LOST: |
| 448 | case SCTP_SHUTDOWN_COMP: |
| 449 | { |
| 450 | struct nodeinfo *ni; |
| 451 | |
| 452 | ni = assoc2nodeinfo(sn->sn_assoc_change.sac_assoc_id); |
| 453 | if (ni) { |
| 454 | spin_lock(&ni->lock); |
| 455 | ni->assoc_id = 0; |
| 456 | spin_unlock(&ni->lock); |
| 457 | } |
| 458 | } |
| 459 | break; |
| 460 | |
| 461 | /* We don't know which INIT failed, so clear the PENDING flags |
| 462 | * on them all. if assoc_id is zero then it will then try |
| 463 | * again */ |
| 464 | |
| 465 | case SCTP_CANT_STR_ASSOC: |
| 466 | { |
| 467 | log_print("Can't start SCTP association - retrying"); |
| 468 | init_failed(); |
| 469 | } |
| 470 | break; |
| 471 | |
| 472 | default: |
| 473 | log_print("unexpected SCTP assoc change id=%d state=%d", |
| 474 | (int)sn->sn_assoc_change.sac_assoc_id, |
| 475 | sn->sn_assoc_change.sac_state); |
| 476 | } |
| 477 | } |
| 478 | } |
| 479 | |
| 480 | /* Data received from remote end */ |
| 481 | static int receive_from_sock(void) |
| 482 | { |
| 483 | int ret = 0; |
| 484 | struct msghdr msg; |
| 485 | struct kvec iov[2]; |
| 486 | unsigned len; |
| 487 | int r; |
| 488 | struct sctp_sndrcvinfo *sinfo; |
| 489 | struct cmsghdr *cmsg; |
| 490 | struct nodeinfo *ni; |
| 491 | |
| 492 | /* These two are marginally too big for stack allocation, but this |
| 493 | * function is (currently) only called by dlm_recvd so static should be |
| 494 | * OK. |
| 495 | */ |
| 496 | static struct sockaddr_storage msgname; |
| 497 | static char incmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))]; |
| 498 | |
| 499 | if (sctp_con.sock == NULL) |
| 500 | goto out; |
| 501 | |
| 502 | if (sctp_con.rx_page == NULL) { |
| 503 | /* |
| 504 | * This doesn't need to be atomic, but I think it should |
| 505 | * improve performance if it is. |
| 506 | */ |
| 507 | sctp_con.rx_page = alloc_page(GFP_ATOMIC); |
| 508 | if (sctp_con.rx_page == NULL) |
| 509 | goto out_resched; |
| 510 | CBUF_INIT(&sctp_con.cb, PAGE_CACHE_SIZE); |
| 511 | } |
| 512 | |
| 513 | memset(&incmsg, 0, sizeof(incmsg)); |
| 514 | memset(&msgname, 0, sizeof(msgname)); |
| 515 | |
| 516 | memset(incmsg, 0, sizeof(incmsg)); |
| 517 | msg.msg_name = &msgname; |
| 518 | msg.msg_namelen = sizeof(msgname); |
| 519 | msg.msg_flags = 0; |
| 520 | msg.msg_control = incmsg; |
| 521 | msg.msg_controllen = sizeof(incmsg); |
| 522 | |
| 523 | /* I don't see why this circular buffer stuff is necessary for SCTP |
| 524 | * which is a packet-based protocol, but the whole thing breaks under |
| 525 | * load without it! The overhead is minimal (and is in the TCP lowcomms |
| 526 | * anyway, of course) so I'll leave it in until I can figure out what's |
| 527 | * really happening. |
| 528 | */ |
| 529 | |
| 530 | /* |
| 531 | * iov[0] is the bit of the circular buffer between the current end |
| 532 | * point (cb.base + cb.len) and the end of the buffer. |
| 533 | */ |
| 534 | iov[0].iov_len = sctp_con.cb.base - CBUF_DATA(&sctp_con.cb); |
| 535 | iov[0].iov_base = page_address(sctp_con.rx_page) + |
| 536 | CBUF_DATA(&sctp_con.cb); |
| 537 | iov[1].iov_len = 0; |
| 538 | |
| 539 | /* |
| 540 | * iov[1] is the bit of the circular buffer between the start of the |
| 541 | * buffer and the start of the currently used section (cb.base) |
| 542 | */ |
| 543 | if (CBUF_DATA(&sctp_con.cb) >= sctp_con.cb.base) { |
| 544 | iov[0].iov_len = PAGE_CACHE_SIZE - CBUF_DATA(&sctp_con.cb); |
| 545 | iov[1].iov_len = sctp_con.cb.base; |
| 546 | iov[1].iov_base = page_address(sctp_con.rx_page); |
| 547 | msg.msg_iovlen = 2; |
| 548 | } |
| 549 | len = iov[0].iov_len + iov[1].iov_len; |
| 550 | |
| 551 | r = ret = kernel_recvmsg(sctp_con.sock, &msg, iov, 1, len, |
| 552 | MSG_NOSIGNAL | MSG_DONTWAIT); |
| 553 | if (ret <= 0) |
| 554 | goto out_close; |
| 555 | |
| 556 | msg.msg_control = incmsg; |
| 557 | msg.msg_controllen = sizeof(incmsg); |
| 558 | cmsg = CMSG_FIRSTHDR(&msg); |
| 559 | sinfo = (struct sctp_sndrcvinfo *)CMSG_DATA(cmsg); |
| 560 | |
| 561 | if (msg.msg_flags & MSG_NOTIFICATION) { |
| 562 | process_sctp_notification(&msg, page_address(sctp_con.rx_page)); |
| 563 | return 0; |
| 564 | } |
| 565 | |
| 566 | /* Is this a new association ? */ |
| 567 | ni = nodeid2nodeinfo(le32_to_cpu(sinfo->sinfo_ppid), GFP_KERNEL); |
| 568 | if (ni) { |
| 569 | ni->assoc_id = sinfo->sinfo_assoc_id; |
| 570 | if (test_and_clear_bit(NI_INIT_PENDING, &ni->flags)) { |
| 571 | |
| 572 | if (!test_and_set_bit(NI_WRITE_PENDING, &ni->flags)) { |
| 573 | spin_lock_bh(&write_nodes_lock); |
| 574 | list_add_tail(&ni->write_list, &write_nodes); |
| 575 | spin_unlock_bh(&write_nodes_lock); |
| 576 | } |
| 577 | wake_up_process(send_task); |
| 578 | } |
| 579 | } |
| 580 | |
| 581 | /* INIT sends a message with length of 1 - ignore it */ |
| 582 | if (r == 1) |
| 583 | return 0; |
| 584 | |
| 585 | CBUF_ADD(&sctp_con.cb, ret); |
| 586 | ret = dlm_process_incoming_buffer(cpu_to_le32(sinfo->sinfo_ppid), |
| 587 | page_address(sctp_con.rx_page), |
| 588 | sctp_con.cb.base, sctp_con.cb.len, |
| 589 | PAGE_CACHE_SIZE); |
| 590 | if (ret < 0) |
| 591 | goto out_close; |
| 592 | CBUF_EAT(&sctp_con.cb, ret); |
| 593 | |
| 594 | out: |
| 595 | ret = 0; |
| 596 | goto out_ret; |
| 597 | |
| 598 | out_resched: |
| 599 | lowcomms_data_ready(sctp_con.sock->sk, 0); |
| 600 | ret = 0; |
| 601 | schedule(); |
| 602 | goto out_ret; |
| 603 | |
| 604 | out_close: |
| 605 | if (ret != -EAGAIN) |
| 606 | log_print("error reading from sctp socket: %d", ret); |
| 607 | out_ret: |
| 608 | return ret; |
| 609 | } |
| 610 | |
| 611 | /* Bind to an IP address. SCTP allows multiple address so it can do multi-homing */ |
| 612 | static int add_bind_addr(struct sockaddr_storage *addr, int addr_len, int num) |
| 613 | { |
| 614 | mm_segment_t fs; |
| 615 | int result = 0; |
| 616 | |
| 617 | fs = get_fs(); |
| 618 | set_fs(get_ds()); |
| 619 | if (num == 1) |
| 620 | result = sctp_con.sock->ops->bind(sctp_con.sock, |
| 621 | (struct sockaddr *) addr, addr_len); |
| 622 | else |
| 623 | result = sctp_con.sock->ops->setsockopt(sctp_con.sock, SOL_SCTP, |
| 624 | SCTP_SOCKOPT_BINDX_ADD, (char *)addr, addr_len); |
| 625 | set_fs(fs); |
| 626 | |
| 627 | if (result < 0) |
| 628 | log_print("Can't bind to port %d addr number %d", |
| 629 | dlm_config.tcp_port, num); |
| 630 | |
| 631 | return result; |
| 632 | } |
| 633 | |
| 634 | static void init_local(void) |
| 635 | { |
| 636 | struct sockaddr_storage sas, *addr; |
| 637 | int i; |
| 638 | |
Steven Whitehouse | 47c96298 | 2006-05-25 17:43:14 -0400 | [diff] [blame] | 639 | dlm_local_nodeid = dlm_our_nodeid(); |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 640 | |
| 641 | for (i = 0; i < DLM_MAX_ADDR_COUNT - 1; i++) { |
| 642 | if (dlm_our_addr(&sas, i)) |
| 643 | break; |
| 644 | |
| 645 | addr = kmalloc(sizeof(*addr), GFP_KERNEL); |
| 646 | if (!addr) |
| 647 | break; |
| 648 | memcpy(addr, &sas, sizeof(*addr)); |
Steven Whitehouse | 47c96298 | 2006-05-25 17:43:14 -0400 | [diff] [blame] | 649 | dlm_local_addr[dlm_local_count++] = addr; |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 650 | } |
| 651 | } |
| 652 | |
| 653 | /* Initialise SCTP socket and bind to all interfaces */ |
| 654 | static int init_sock(void) |
| 655 | { |
| 656 | mm_segment_t fs; |
| 657 | struct socket *sock = NULL; |
| 658 | struct sockaddr_storage localaddr; |
| 659 | struct sctp_event_subscribe subscribe; |
| 660 | int result = -EINVAL, num = 1, i, addr_len; |
| 661 | |
Steven Whitehouse | 47c96298 | 2006-05-25 17:43:14 -0400 | [diff] [blame] | 662 | if (!dlm_local_count) { |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 663 | init_local(); |
Steven Whitehouse | 47c96298 | 2006-05-25 17:43:14 -0400 | [diff] [blame] | 664 | if (!dlm_local_count) { |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 665 | log_print("no local IP address has been set"); |
| 666 | goto out; |
| 667 | } |
| 668 | } |
| 669 | |
Steven Whitehouse | 47c96298 | 2006-05-25 17:43:14 -0400 | [diff] [blame] | 670 | result = sock_create_kern(dlm_local_addr[0]->ss_family, SOCK_SEQPACKET, |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 671 | IPPROTO_SCTP, &sock); |
| 672 | if (result < 0) { |
| 673 | log_print("Can't create comms socket, check SCTP is loaded"); |
| 674 | goto out; |
| 675 | } |
| 676 | |
| 677 | /* Listen for events */ |
| 678 | memset(&subscribe, 0, sizeof(subscribe)); |
| 679 | subscribe.sctp_data_io_event = 1; |
| 680 | subscribe.sctp_association_event = 1; |
| 681 | subscribe.sctp_send_failure_event = 1; |
| 682 | subscribe.sctp_shutdown_event = 1; |
| 683 | subscribe.sctp_partial_delivery_event = 1; |
| 684 | |
| 685 | fs = get_fs(); |
| 686 | set_fs(get_ds()); |
| 687 | result = sock->ops->setsockopt(sock, SOL_SCTP, SCTP_EVENTS, |
| 688 | (char *)&subscribe, sizeof(subscribe)); |
| 689 | set_fs(fs); |
| 690 | |
| 691 | if (result < 0) { |
| 692 | log_print("Failed to set SCTP_EVENTS on socket: result=%d", |
| 693 | result); |
| 694 | goto create_delsock; |
| 695 | } |
| 696 | |
| 697 | /* Init con struct */ |
| 698 | sock->sk->sk_user_data = &sctp_con; |
| 699 | sctp_con.sock = sock; |
| 700 | sctp_con.sock->sk->sk_data_ready = lowcomms_data_ready; |
| 701 | |
| 702 | /* Bind to all interfaces. */ |
Steven Whitehouse | 47c96298 | 2006-05-25 17:43:14 -0400 | [diff] [blame] | 703 | for (i = 0; i < dlm_local_count; i++) { |
| 704 | memcpy(&localaddr, dlm_local_addr[i], sizeof(localaddr)); |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 705 | make_sockaddr(&localaddr, dlm_config.tcp_port, &addr_len); |
| 706 | |
| 707 | result = add_bind_addr(&localaddr, addr_len, num); |
| 708 | if (result) |
| 709 | goto create_delsock; |
| 710 | ++num; |
| 711 | } |
| 712 | |
| 713 | result = sock->ops->listen(sock, 5); |
| 714 | if (result < 0) { |
| 715 | log_print("Can't set socket listening"); |
| 716 | goto create_delsock; |
| 717 | } |
| 718 | |
| 719 | return 0; |
| 720 | |
| 721 | create_delsock: |
| 722 | sock_release(sock); |
| 723 | sctp_con.sock = NULL; |
| 724 | out: |
| 725 | return result; |
| 726 | } |
| 727 | |
| 728 | |
| 729 | static struct writequeue_entry *new_writequeue_entry(int allocation) |
| 730 | { |
| 731 | struct writequeue_entry *entry; |
| 732 | |
| 733 | entry = kmalloc(sizeof(struct writequeue_entry), allocation); |
| 734 | if (!entry) |
| 735 | return NULL; |
| 736 | |
| 737 | entry->page = alloc_page(allocation); |
| 738 | if (!entry->page) { |
| 739 | kfree(entry); |
| 740 | return NULL; |
| 741 | } |
| 742 | |
| 743 | entry->offset = 0; |
| 744 | entry->len = 0; |
| 745 | entry->end = 0; |
| 746 | entry->users = 0; |
| 747 | |
| 748 | return entry; |
| 749 | } |
| 750 | |
| 751 | void *dlm_lowcomms_get_buffer(int nodeid, int len, int allocation, char **ppc) |
| 752 | { |
| 753 | struct writequeue_entry *e; |
| 754 | int offset = 0; |
| 755 | int users = 0; |
| 756 | struct nodeinfo *ni; |
| 757 | |
| 758 | if (!atomic_read(&accepting)) |
| 759 | return NULL; |
| 760 | |
| 761 | ni = nodeid2nodeinfo(nodeid, allocation); |
| 762 | if (!ni) |
| 763 | return NULL; |
| 764 | |
| 765 | spin_lock(&ni->writequeue_lock); |
| 766 | e = list_entry(ni->writequeue.prev, struct writequeue_entry, list); |
| 767 | if (((struct list_head *) e == &ni->writequeue) || |
| 768 | (PAGE_CACHE_SIZE - e->end < len)) { |
| 769 | e = NULL; |
| 770 | } else { |
| 771 | offset = e->end; |
| 772 | e->end += len; |
| 773 | users = e->users++; |
| 774 | } |
| 775 | spin_unlock(&ni->writequeue_lock); |
| 776 | |
| 777 | if (e) { |
| 778 | got_one: |
| 779 | if (users == 0) |
| 780 | kmap(e->page); |
| 781 | *ppc = page_address(e->page) + offset; |
| 782 | return e; |
| 783 | } |
| 784 | |
| 785 | e = new_writequeue_entry(allocation); |
| 786 | if (e) { |
| 787 | spin_lock(&ni->writequeue_lock); |
| 788 | offset = e->end; |
| 789 | e->end += len; |
| 790 | e->ni = ni; |
| 791 | users = e->users++; |
| 792 | list_add_tail(&e->list, &ni->writequeue); |
| 793 | spin_unlock(&ni->writequeue_lock); |
| 794 | goto got_one; |
| 795 | } |
| 796 | return NULL; |
| 797 | } |
| 798 | |
| 799 | void dlm_lowcomms_commit_buffer(void *arg) |
| 800 | { |
| 801 | struct writequeue_entry *e = (struct writequeue_entry *) arg; |
| 802 | int users; |
| 803 | struct nodeinfo *ni = e->ni; |
| 804 | |
| 805 | if (!atomic_read(&accepting)) |
| 806 | return; |
| 807 | |
| 808 | spin_lock(&ni->writequeue_lock); |
| 809 | users = --e->users; |
| 810 | if (users) |
| 811 | goto out; |
| 812 | e->len = e->end - e->offset; |
| 813 | kunmap(e->page); |
| 814 | spin_unlock(&ni->writequeue_lock); |
| 815 | |
| 816 | if (!test_and_set_bit(NI_WRITE_PENDING, &ni->flags)) { |
| 817 | spin_lock_bh(&write_nodes_lock); |
| 818 | list_add_tail(&ni->write_list, &write_nodes); |
| 819 | spin_unlock_bh(&write_nodes_lock); |
| 820 | wake_up_process(send_task); |
| 821 | } |
| 822 | return; |
| 823 | |
| 824 | out: |
| 825 | spin_unlock(&ni->writequeue_lock); |
| 826 | return; |
| 827 | } |
| 828 | |
| 829 | static void free_entry(struct writequeue_entry *e) |
| 830 | { |
| 831 | __free_page(e->page); |
| 832 | kfree(e); |
| 833 | } |
| 834 | |
| 835 | /* Initiate an SCTP association. In theory we could just use sendmsg() on |
| 836 | the first IP address and it should work, but this allows us to set up the |
| 837 | association before sending any valuable data that we can't afford to lose. |
| 838 | It also keeps the send path clean as it can now always use the association ID */ |
| 839 | static void initiate_association(int nodeid) |
| 840 | { |
| 841 | struct sockaddr_storage rem_addr; |
| 842 | static char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))]; |
| 843 | struct msghdr outmessage; |
| 844 | struct cmsghdr *cmsg; |
| 845 | struct sctp_sndrcvinfo *sinfo; |
| 846 | int ret; |
| 847 | int addrlen; |
| 848 | char buf[1]; |
| 849 | struct kvec iov[1]; |
| 850 | struct nodeinfo *ni; |
| 851 | |
| 852 | log_print("Initiating association with node %d", nodeid); |
| 853 | |
| 854 | ni = nodeid2nodeinfo(nodeid, GFP_KERNEL); |
| 855 | if (!ni) |
| 856 | return; |
| 857 | |
| 858 | if (nodeid_to_addr(nodeid, (struct sockaddr *)&rem_addr)) { |
| 859 | log_print("no address for nodeid %d", nodeid); |
| 860 | return; |
| 861 | } |
| 862 | |
| 863 | make_sockaddr(&rem_addr, dlm_config.tcp_port, &addrlen); |
| 864 | |
| 865 | outmessage.msg_name = &rem_addr; |
| 866 | outmessage.msg_namelen = addrlen; |
| 867 | outmessage.msg_control = outcmsg; |
| 868 | outmessage.msg_controllen = sizeof(outcmsg); |
| 869 | outmessage.msg_flags = MSG_EOR; |
| 870 | |
| 871 | iov[0].iov_base = buf; |
| 872 | iov[0].iov_len = 1; |
| 873 | |
| 874 | /* Real INIT messages seem to cause trouble. Just send a 1 byte message |
| 875 | we can afford to lose */ |
| 876 | cmsg = CMSG_FIRSTHDR(&outmessage); |
| 877 | cmsg->cmsg_level = IPPROTO_SCTP; |
| 878 | cmsg->cmsg_type = SCTP_SNDRCV; |
| 879 | cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo)); |
| 880 | sinfo = (struct sctp_sndrcvinfo *)CMSG_DATA(cmsg); |
| 881 | memset(sinfo, 0x00, sizeof(struct sctp_sndrcvinfo)); |
Steven Whitehouse | 47c96298 | 2006-05-25 17:43:14 -0400 | [diff] [blame] | 882 | sinfo->sinfo_ppid = cpu_to_le32(dlm_local_nodeid); |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 883 | |
| 884 | outmessage.msg_controllen = cmsg->cmsg_len; |
| 885 | ret = kernel_sendmsg(sctp_con.sock, &outmessage, iov, 1, 1); |
| 886 | if (ret < 0) { |
| 887 | log_print("send INIT to node failed: %d", ret); |
| 888 | /* Try again later */ |
| 889 | clear_bit(NI_INIT_PENDING, &ni->flags); |
| 890 | } |
| 891 | } |
| 892 | |
| 893 | /* Send a message */ |
| 894 | static int send_to_sock(struct nodeinfo *ni) |
| 895 | { |
| 896 | int ret = 0; |
| 897 | struct writequeue_entry *e; |
| 898 | int len, offset; |
| 899 | struct msghdr outmsg; |
| 900 | static char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))]; |
| 901 | struct cmsghdr *cmsg; |
| 902 | struct sctp_sndrcvinfo *sinfo; |
| 903 | struct kvec iov; |
| 904 | |
| 905 | /* See if we need to init an association before we start |
| 906 | sending precious messages */ |
| 907 | spin_lock(&ni->lock); |
| 908 | if (!ni->assoc_id && !test_and_set_bit(NI_INIT_PENDING, &ni->flags)) { |
| 909 | spin_unlock(&ni->lock); |
| 910 | initiate_association(ni->nodeid); |
| 911 | return 0; |
| 912 | } |
| 913 | spin_unlock(&ni->lock); |
| 914 | |
| 915 | outmsg.msg_name = NULL; /* We use assoc_id */ |
| 916 | outmsg.msg_namelen = 0; |
| 917 | outmsg.msg_control = outcmsg; |
| 918 | outmsg.msg_controllen = sizeof(outcmsg); |
| 919 | outmsg.msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL | MSG_EOR; |
| 920 | |
| 921 | cmsg = CMSG_FIRSTHDR(&outmsg); |
| 922 | cmsg->cmsg_level = IPPROTO_SCTP; |
| 923 | cmsg->cmsg_type = SCTP_SNDRCV; |
| 924 | cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo)); |
| 925 | sinfo = (struct sctp_sndrcvinfo *)CMSG_DATA(cmsg); |
| 926 | memset(sinfo, 0x00, sizeof(struct sctp_sndrcvinfo)); |
Steven Whitehouse | 47c96298 | 2006-05-25 17:43:14 -0400 | [diff] [blame] | 927 | sinfo->sinfo_ppid = cpu_to_le32(dlm_local_nodeid); |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 928 | sinfo->sinfo_assoc_id = ni->assoc_id; |
| 929 | outmsg.msg_controllen = cmsg->cmsg_len; |
| 930 | |
| 931 | spin_lock(&ni->writequeue_lock); |
| 932 | for (;;) { |
| 933 | if (list_empty(&ni->writequeue)) |
| 934 | break; |
| 935 | e = list_entry(ni->writequeue.next, struct writequeue_entry, |
| 936 | list); |
| 937 | kmap(e->page); |
| 938 | len = e->len; |
| 939 | offset = e->offset; |
| 940 | BUG_ON(len == 0 && e->users == 0); |
| 941 | spin_unlock(&ni->writequeue_lock); |
| 942 | |
| 943 | ret = 0; |
| 944 | if (len) { |
| 945 | iov.iov_base = page_address(e->page)+offset; |
| 946 | iov.iov_len = len; |
| 947 | |
| 948 | ret = kernel_sendmsg(sctp_con.sock, &outmsg, &iov, 1, |
| 949 | len); |
| 950 | if (ret == -EAGAIN) { |
| 951 | sctp_con.eagain_flag = 1; |
| 952 | goto out; |
| 953 | } else if (ret < 0) |
| 954 | goto send_error; |
| 955 | } else { |
| 956 | /* Don't starve people filling buffers */ |
| 957 | schedule(); |
| 958 | } |
| 959 | |
| 960 | spin_lock(&ni->writequeue_lock); |
| 961 | e->offset += ret; |
| 962 | e->len -= ret; |
| 963 | |
| 964 | if (e->len == 0 && e->users == 0) { |
| 965 | list_del(&e->list); |
| 966 | free_entry(e); |
| 967 | continue; |
| 968 | } |
| 969 | } |
| 970 | spin_unlock(&ni->writequeue_lock); |
| 971 | out: |
| 972 | return ret; |
| 973 | |
| 974 | send_error: |
| 975 | log_print("Error sending to node %d %d", ni->nodeid, ret); |
| 976 | spin_lock(&ni->lock); |
| 977 | if (!test_and_set_bit(NI_INIT_PENDING, &ni->flags)) { |
| 978 | ni->assoc_id = 0; |
| 979 | spin_unlock(&ni->lock); |
| 980 | initiate_association(ni->nodeid); |
| 981 | } else |
| 982 | spin_unlock(&ni->lock); |
| 983 | |
| 984 | return ret; |
| 985 | } |
| 986 | |
| 987 | /* Try to send any messages that are pending */ |
| 988 | static void process_output_queue(void) |
| 989 | { |
| 990 | struct list_head *list; |
| 991 | struct list_head *temp; |
| 992 | |
| 993 | spin_lock_bh(&write_nodes_lock); |
| 994 | list_for_each_safe(list, temp, &write_nodes) { |
| 995 | struct nodeinfo *ni = |
| 996 | list_entry(list, struct nodeinfo, write_list); |
| 997 | clear_bit(NI_WRITE_PENDING, &ni->flags); |
| 998 | list_del(&ni->write_list); |
| 999 | |
| 1000 | spin_unlock_bh(&write_nodes_lock); |
| 1001 | |
| 1002 | send_to_sock(ni); |
| 1003 | spin_lock_bh(&write_nodes_lock); |
| 1004 | } |
| 1005 | spin_unlock_bh(&write_nodes_lock); |
| 1006 | } |
| 1007 | |
| 1008 | /* Called after we've had -EAGAIN and been woken up */ |
| 1009 | static void refill_write_queue(void) |
| 1010 | { |
| 1011 | int i; |
| 1012 | |
| 1013 | for (i=1; i<=max_nodeid; i++) { |
| 1014 | struct nodeinfo *ni = nodeid2nodeinfo(i, 0); |
| 1015 | |
| 1016 | if (ni) { |
| 1017 | if (!test_and_set_bit(NI_WRITE_PENDING, &ni->flags)) { |
| 1018 | spin_lock_bh(&write_nodes_lock); |
| 1019 | list_add_tail(&ni->write_list, &write_nodes); |
| 1020 | spin_unlock_bh(&write_nodes_lock); |
| 1021 | } |
| 1022 | } |
| 1023 | } |
| 1024 | } |
| 1025 | |
| 1026 | static void clean_one_writequeue(struct nodeinfo *ni) |
| 1027 | { |
| 1028 | struct list_head *list; |
| 1029 | struct list_head *temp; |
| 1030 | |
| 1031 | spin_lock(&ni->writequeue_lock); |
| 1032 | list_for_each_safe(list, temp, &ni->writequeue) { |
| 1033 | struct writequeue_entry *e = |
| 1034 | list_entry(list, struct writequeue_entry, list); |
| 1035 | list_del(&e->list); |
| 1036 | free_entry(e); |
| 1037 | } |
| 1038 | spin_unlock(&ni->writequeue_lock); |
| 1039 | } |
| 1040 | |
| 1041 | static void clean_writequeues(void) |
| 1042 | { |
| 1043 | int i; |
| 1044 | |
| 1045 | for (i=1; i<=max_nodeid; i++) { |
| 1046 | struct nodeinfo *ni = nodeid2nodeinfo(i, 0); |
| 1047 | if (ni) |
| 1048 | clean_one_writequeue(ni); |
| 1049 | } |
| 1050 | } |
| 1051 | |
| 1052 | |
| 1053 | static void dealloc_nodeinfo(void) |
| 1054 | { |
| 1055 | int i; |
| 1056 | |
| 1057 | for (i=1; i<=max_nodeid; i++) { |
| 1058 | struct nodeinfo *ni = nodeid2nodeinfo(i, 0); |
| 1059 | if (ni) { |
| 1060 | idr_remove(&nodeinfo_idr, i); |
| 1061 | kfree(ni); |
| 1062 | } |
| 1063 | } |
| 1064 | } |
| 1065 | |
David Teigland | 1c032c0 | 2006-04-28 10:50:41 -0400 | [diff] [blame] | 1066 | int dlm_lowcomms_close(int nodeid) |
| 1067 | { |
| 1068 | struct nodeinfo *ni; |
| 1069 | |
| 1070 | ni = nodeid2nodeinfo(nodeid, 0); |
| 1071 | if (!ni) |
| 1072 | return -1; |
| 1073 | |
| 1074 | spin_lock(&ni->lock); |
| 1075 | if (ni->assoc_id) { |
| 1076 | ni->assoc_id = 0; |
| 1077 | /* Don't send shutdown here, sctp will just queue it |
| 1078 | till the node comes back up! */ |
| 1079 | } |
| 1080 | spin_unlock(&ni->lock); |
| 1081 | |
| 1082 | clean_one_writequeue(ni); |
| 1083 | clear_bit(NI_INIT_PENDING, &ni->flags); |
| 1084 | return 0; |
| 1085 | } |
| 1086 | |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 1087 | static int write_list_empty(void) |
| 1088 | { |
| 1089 | int status; |
| 1090 | |
| 1091 | spin_lock_bh(&write_nodes_lock); |
| 1092 | status = list_empty(&write_nodes); |
| 1093 | spin_unlock_bh(&write_nodes_lock); |
| 1094 | |
| 1095 | return status; |
| 1096 | } |
| 1097 | |
| 1098 | static int dlm_recvd(void *data) |
| 1099 | { |
| 1100 | DECLARE_WAITQUEUE(wait, current); |
| 1101 | |
| 1102 | while (!kthread_should_stop()) { |
| 1103 | int count = 0; |
| 1104 | |
| 1105 | set_current_state(TASK_INTERRUPTIBLE); |
| 1106 | add_wait_queue(&lowcomms_recv_wait, &wait); |
| 1107 | if (!test_bit(CF_READ_PENDING, &sctp_con.flags)) |
| 1108 | schedule(); |
| 1109 | remove_wait_queue(&lowcomms_recv_wait, &wait); |
| 1110 | set_current_state(TASK_RUNNING); |
| 1111 | |
| 1112 | if (test_and_clear_bit(CF_READ_PENDING, &sctp_con.flags)) { |
| 1113 | int ret; |
| 1114 | |
| 1115 | do { |
| 1116 | ret = receive_from_sock(); |
| 1117 | |
| 1118 | /* Don't starve out everyone else */ |
| 1119 | if (++count >= MAX_RX_MSG_COUNT) { |
| 1120 | schedule(); |
| 1121 | count = 0; |
| 1122 | } |
| 1123 | } while (!kthread_should_stop() && ret >=0); |
| 1124 | } |
| 1125 | schedule(); |
| 1126 | } |
| 1127 | |
| 1128 | return 0; |
| 1129 | } |
| 1130 | |
| 1131 | static int dlm_sendd(void *data) |
| 1132 | { |
| 1133 | DECLARE_WAITQUEUE(wait, current); |
| 1134 | |
| 1135 | add_wait_queue(sctp_con.sock->sk->sk_sleep, &wait); |
| 1136 | |
| 1137 | while (!kthread_should_stop()) { |
| 1138 | set_current_state(TASK_INTERRUPTIBLE); |
| 1139 | if (write_list_empty()) |
| 1140 | schedule(); |
| 1141 | set_current_state(TASK_RUNNING); |
| 1142 | |
| 1143 | if (sctp_con.eagain_flag) { |
| 1144 | sctp_con.eagain_flag = 0; |
| 1145 | refill_write_queue(); |
| 1146 | } |
| 1147 | process_output_queue(); |
| 1148 | } |
| 1149 | |
| 1150 | remove_wait_queue(sctp_con.sock->sk->sk_sleep, &wait); |
| 1151 | |
| 1152 | return 0; |
| 1153 | } |
| 1154 | |
| 1155 | static void daemons_stop(void) |
| 1156 | { |
| 1157 | kthread_stop(recv_task); |
| 1158 | kthread_stop(send_task); |
| 1159 | } |
| 1160 | |
| 1161 | static int daemons_start(void) |
| 1162 | { |
| 1163 | struct task_struct *p; |
| 1164 | int error; |
| 1165 | |
| 1166 | p = kthread_run(dlm_recvd, NULL, "dlm_recvd"); |
| 1167 | error = IS_ERR(p); |
| 1168 | if (error) { |
| 1169 | log_print("can't start dlm_recvd %d", error); |
| 1170 | return error; |
| 1171 | } |
| 1172 | recv_task = p; |
| 1173 | |
| 1174 | p = kthread_run(dlm_sendd, NULL, "dlm_sendd"); |
| 1175 | error = IS_ERR(p); |
| 1176 | if (error) { |
| 1177 | log_print("can't start dlm_sendd %d", error); |
| 1178 | kthread_stop(recv_task); |
| 1179 | return error; |
| 1180 | } |
| 1181 | send_task = p; |
| 1182 | |
| 1183 | return 0; |
| 1184 | } |
| 1185 | |
| 1186 | /* |
| 1187 | * This is quite likely to sleep... |
| 1188 | */ |
| 1189 | int dlm_lowcomms_start(void) |
| 1190 | { |
| 1191 | int error; |
| 1192 | |
| 1193 | spin_lock_init(&write_nodes_lock); |
| 1194 | INIT_LIST_HEAD(&write_nodes); |
| 1195 | init_rwsem(&nodeinfo_lock); |
| 1196 | |
| 1197 | error = init_sock(); |
| 1198 | if (error) |
| 1199 | goto fail_sock; |
| 1200 | error = daemons_start(); |
| 1201 | if (error) |
| 1202 | goto fail_sock; |
| 1203 | atomic_set(&accepting, 1); |
| 1204 | return 0; |
| 1205 | |
| 1206 | fail_sock: |
| 1207 | close_connection(); |
| 1208 | return error; |
| 1209 | } |
| 1210 | |
| 1211 | /* Set all the activity flags to prevent any socket activity. */ |
| 1212 | |
| 1213 | void dlm_lowcomms_stop(void) |
| 1214 | { |
| 1215 | atomic_set(&accepting, 0); |
| 1216 | sctp_con.flags = 0x7; |
| 1217 | daemons_stop(); |
| 1218 | clean_writequeues(); |
| 1219 | close_connection(); |
| 1220 | dealloc_nodeinfo(); |
| 1221 | max_nodeid = 0; |
| 1222 | } |
| 1223 | |
| 1224 | int dlm_lowcomms_init(void) |
| 1225 | { |
| 1226 | init_waitqueue_head(&lowcomms_recv_wait); |
| 1227 | return 0; |
| 1228 | } |
| 1229 | |
| 1230 | void dlm_lowcomms_exit(void) |
| 1231 | { |
| 1232 | int i; |
| 1233 | |
Steven Whitehouse | 47c96298 | 2006-05-25 17:43:14 -0400 | [diff] [blame] | 1234 | for (i = 0; i < dlm_local_count; i++) |
| 1235 | kfree(dlm_local_addr[i]); |
| 1236 | dlm_local_count = 0; |
| 1237 | dlm_local_nodeid = 0; |
David Teigland | e7fd417 | 2006-01-18 09:30:29 +0000 | [diff] [blame] | 1238 | } |
| 1239 | |