1 /* 2 * hvc_iucv.c - z/VM IUCV hypervisor console (HVC) device driver 3 * 4 * This HVC device driver provides terminal access using 5 * z/VM IUCV communication paths. 6 * 7 * Copyright IBM Corp. 2008, 2009 8 * 9 * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com> 10 */ 11 #define KMSG_COMPONENT "hvc_iucv" 12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 13 14 #include <linux/types.h> 15 #include <linux/slab.h> 16 #include <asm/ebcdic.h> 17 #include <linux/ctype.h> 18 #include <linux/delay.h> 19 #include <linux/device.h> 20 #include <linux/init.h> 21 #include <linux/mempool.h> 22 #include <linux/moduleparam.h> 23 #include <linux/tty.h> 24 #include <linux/wait.h> 25 #include <net/iucv/iucv.h> 26 27 #include "hvc_console.h" 28 29 30 /* General device driver settings */ 31 #define HVC_IUCV_MAGIC 0xc9e4c3e5 32 #define MAX_HVC_IUCV_LINES HVC_ALLOC_TTY_ADAPTERS 33 #define MEMPOOL_MIN_NR (PAGE_SIZE / sizeof(struct iucv_tty_buffer)/4) 34 35 /* IUCV TTY message */ 36 #define MSG_VERSION 0x02 /* Message version */ 37 #define MSG_TYPE_ERROR 0x01 /* Error message */ 38 #define MSG_TYPE_TERMENV 0x02 /* Terminal environment variable */ 39 #define MSG_TYPE_TERMIOS 0x04 /* Terminal IO struct update */ 40 #define MSG_TYPE_WINSIZE 0x08 /* Terminal window size update */ 41 #define MSG_TYPE_DATA 0x10 /* Terminal data */ 42 43 struct iucv_tty_msg { 44 u8 version; /* Message version */ 45 u8 type; /* Message type */ 46 #define MSG_MAX_DATALEN ((u16)(~0)) 47 u16 datalen; /* Payload length */ 48 u8 data[]; /* Payload buffer */ 49 } __attribute__((packed)); 50 #define MSG_SIZE(s) ((s) + offsetof(struct iucv_tty_msg, data)) 51 52 enum iucv_state_t { 53 IUCV_DISCONN = 0, 54 IUCV_CONNECTED = 1, 55 IUCV_SEVERED = 2, 56 }; 57 58 enum tty_state_t { 59 TTY_CLOSED = 0, 60 TTY_OPENED = 1, 61 }; 62 63 struct hvc_iucv_private { 64 struct hvc_struct *hvc; /* HVC struct reference */ 65 u8 srv_name[8]; /* IUCV service name (ebcdic) */ 66 unsigned char is_console; /* Linux console usage flag */ 67 enum iucv_state_t iucv_state; /* IUCV connection status */ 68 enum tty_state_t tty_state; /* TTY status */ 69 struct iucv_path *path; /* IUCV path pointer */ 70 spinlock_t lock; /* hvc_iucv_private lock */ 71 #define SNDBUF_SIZE (PAGE_SIZE) /* must be < MSG_MAX_DATALEN */ 72 void *sndbuf; /* send buffer */ 73 size_t sndbuf_len; /* length of send buffer */ 74 #define QUEUE_SNDBUF_DELAY (HZ / 25) 75 struct delayed_work sndbuf_work; /* work: send iucv msg(s) */ 76 wait_queue_head_t sndbuf_waitq; /* wait for send completion */ 77 struct list_head tty_outqueue; /* outgoing IUCV messages */ 78 struct list_head tty_inqueue; /* incoming IUCV messages */ 79 struct device *dev; /* device structure */ 80 }; 81 82 struct iucv_tty_buffer { 83 struct list_head list; /* list pointer */ 84 struct iucv_message msg; /* store an IUCV message */ 85 size_t offset; /* data buffer offset */ 86 struct iucv_tty_msg *mbuf; /* buffer to store input/output data */ 87 }; 88 89 /* IUCV callback handler */ 90 static int hvc_iucv_path_pending(struct iucv_path *, u8[8], u8[16]); 91 static void hvc_iucv_path_severed(struct iucv_path *, u8[16]); 92 static void hvc_iucv_msg_pending(struct iucv_path *, struct iucv_message *); 93 static void hvc_iucv_msg_complete(struct iucv_path *, struct iucv_message *); 94 95 96 /* Kernel module parameter: use one terminal device as default */ 97 static unsigned long hvc_iucv_devices = 1; 98 99 /* Array of allocated hvc iucv tty lines... */ 100 static struct hvc_iucv_private *hvc_iucv_table[MAX_HVC_IUCV_LINES]; 101 #define IUCV_HVC_CON_IDX (0) 102 /* List of z/VM user ID filter entries (struct iucv_vmid_filter) */ 103 #define MAX_VMID_FILTER (500) 104 static size_t hvc_iucv_filter_size; 105 static void *hvc_iucv_filter; 106 static const char *hvc_iucv_filter_string; 107 static DEFINE_RWLOCK(hvc_iucv_filter_lock); 108 109 /* Kmem cache and mempool for iucv_tty_buffer elements */ 110 static struct kmem_cache *hvc_iucv_buffer_cache; 111 static mempool_t *hvc_iucv_mempool; 112 113 /* IUCV handler callback functions */ 114 static struct iucv_handler hvc_iucv_handler = { 115 .path_pending = hvc_iucv_path_pending, 116 .path_severed = hvc_iucv_path_severed, 117 .message_complete = hvc_iucv_msg_complete, 118 .message_pending = hvc_iucv_msg_pending, 119 }; 120 121 122 /** 123 * hvc_iucv_get_private() - Return a struct hvc_iucv_private instance. 124 * @num: The HVC virtual terminal number (vtermno) 125 * 126 * This function returns the struct hvc_iucv_private instance that corresponds 127 * to the HVC virtual terminal number specified as parameter @num. 128 */ 129 struct hvc_iucv_private *hvc_iucv_get_private(uint32_t num) 130 { 131 if ((num < HVC_IUCV_MAGIC) || (num - HVC_IUCV_MAGIC > hvc_iucv_devices)) 132 return NULL; 133 return hvc_iucv_table[num - HVC_IUCV_MAGIC]; 134 } 135 136 /** 137 * alloc_tty_buffer() - Return a new struct iucv_tty_buffer element. 138 * @size: Size of the internal buffer used to store data. 139 * @flags: Memory allocation flags passed to mempool. 140 * 141 * This function allocates a new struct iucv_tty_buffer element and, optionally, 142 * allocates an internal data buffer with the specified size @size. 143 * The internal data buffer is always allocated with GFP_DMA which is 144 * required for receiving and sending data with IUCV. 145 * Note: The total message size arises from the internal buffer size and the 146 * members of the iucv_tty_msg structure. 147 * The function returns NULL if memory allocation has failed. 148 */ 149 static struct iucv_tty_buffer *alloc_tty_buffer(size_t size, gfp_t flags) 150 { 151 struct iucv_tty_buffer *bufp; 152 153 bufp = mempool_alloc(hvc_iucv_mempool, flags); 154 if (!bufp) 155 return NULL; 156 memset(bufp, 0, sizeof(*bufp)); 157 158 if (size > 0) { 159 bufp->msg.length = MSG_SIZE(size); 160 bufp->mbuf = kmalloc(bufp->msg.length, flags | GFP_DMA); 161 if (!bufp->mbuf) { 162 mempool_free(bufp, hvc_iucv_mempool); 163 return NULL; 164 } 165 bufp->mbuf->version = MSG_VERSION; 166 bufp->mbuf->type = MSG_TYPE_DATA; 167 bufp->mbuf->datalen = (u16) size; 168 } 169 return bufp; 170 } 171 172 /** 173 * destroy_tty_buffer() - destroy struct iucv_tty_buffer element. 174 * @bufp: Pointer to a struct iucv_tty_buffer element, SHALL NOT be NULL. 175 */ 176 static void destroy_tty_buffer(struct iucv_tty_buffer *bufp) 177 { 178 kfree(bufp->mbuf); 179 mempool_free(bufp, hvc_iucv_mempool); 180 } 181 182 /** 183 * destroy_tty_buffer_list() - call destroy_tty_buffer() for each list element. 184 * @list: List containing struct iucv_tty_buffer elements. 185 */ 186 static void destroy_tty_buffer_list(struct list_head *list) 187 { 188 struct iucv_tty_buffer *ent, *next; 189 190 list_for_each_entry_safe(ent, next, list, list) { 191 list_del(&ent->list); 192 destroy_tty_buffer(ent); 193 } 194 } 195 196 /** 197 * hvc_iucv_write() - Receive IUCV message & write data to HVC buffer. 198 * @priv: Pointer to struct hvc_iucv_private 199 * @buf: HVC buffer for writing received terminal data. 200 * @count: HVC buffer size. 201 * @has_more_data: Pointer to an int variable. 202 * 203 * The function picks up pending messages from the input queue and receives 204 * the message data that is then written to the specified buffer @buf. 205 * If the buffer size @count is less than the data message size, the 206 * message is kept on the input queue and @has_more_data is set to 1. 207 * If all message data has been written, the message is removed from 208 * the input queue. 209 * 210 * The function returns the number of bytes written to the terminal, zero if 211 * there are no pending data messages available or if there is no established 212 * IUCV path. 213 * If the IUCV path has been severed, then -EPIPE is returned to cause a 214 * hang up (that is issued by the HVC layer). 215 */ 216 static int hvc_iucv_write(struct hvc_iucv_private *priv, 217 char *buf, int count, int *has_more_data) 218 { 219 struct iucv_tty_buffer *rb; 220 int written; 221 int rc; 222 223 /* immediately return if there is no IUCV connection */ 224 if (priv->iucv_state == IUCV_DISCONN) 225 return 0; 226 227 /* if the IUCV path has been severed, return -EPIPE to inform the 228 * HVC layer to hang up the tty device. */ 229 if (priv->iucv_state == IUCV_SEVERED) 230 return -EPIPE; 231 232 /* check if there are pending messages */ 233 if (list_empty(&priv->tty_inqueue)) 234 return 0; 235 236 /* receive an iucv message and flip data to the tty (ldisc) */ 237 rb = list_first_entry(&priv->tty_inqueue, struct iucv_tty_buffer, list); 238 239 written = 0; 240 if (!rb->mbuf) { /* message not yet received ... */ 241 /* allocate mem to store msg data; if no memory is available 242 * then leave the buffer on the list and re-try later */ 243 rb->mbuf = kmalloc(rb->msg.length, GFP_ATOMIC | GFP_DMA); 244 if (!rb->mbuf) 245 return -ENOMEM; 246 247 rc = __iucv_message_receive(priv->path, &rb->msg, 0, 248 rb->mbuf, rb->msg.length, NULL); 249 switch (rc) { 250 case 0: /* Successful */ 251 break; 252 case 2: /* No message found */ 253 case 9: /* Message purged */ 254 break; 255 default: 256 written = -EIO; 257 } 258 /* remove buffer if an error has occurred or received data 259 * is not correct */ 260 if (rc || (rb->mbuf->version != MSG_VERSION) || 261 (rb->msg.length != MSG_SIZE(rb->mbuf->datalen))) 262 goto out_remove_buffer; 263 } 264 265 switch (rb->mbuf->type) { 266 case MSG_TYPE_DATA: 267 written = min_t(int, rb->mbuf->datalen - rb->offset, count); 268 memcpy(buf, rb->mbuf->data + rb->offset, written); 269 if (written < (rb->mbuf->datalen - rb->offset)) { 270 rb->offset += written; 271 *has_more_data = 1; 272 goto out_written; 273 } 274 break; 275 276 case MSG_TYPE_WINSIZE: 277 if (rb->mbuf->datalen != sizeof(struct winsize)) 278 break; 279 /* The caller must ensure that the hvc is locked, which 280 * is the case when called from hvc_iucv_get_chars() */ 281 __hvc_resize(priv->hvc, *((struct winsize *) rb->mbuf->data)); 282 break; 283 284 case MSG_TYPE_ERROR: /* ignored ... */ 285 case MSG_TYPE_TERMENV: /* ignored ... */ 286 case MSG_TYPE_TERMIOS: /* ignored ... */ 287 break; 288 } 289 290 out_remove_buffer: 291 list_del(&rb->list); 292 destroy_tty_buffer(rb); 293 *has_more_data = !list_empty(&priv->tty_inqueue); 294 295 out_written: 296 return written; 297 } 298 299 /** 300 * hvc_iucv_get_chars() - HVC get_chars operation. 301 * @vtermno: HVC virtual terminal number. 302 * @buf: Pointer to a buffer to store data 303 * @count: Size of buffer available for writing 304 * 305 * The HVC thread calls this method to read characters from the back-end. 306 * If an IUCV communication path has been established, pending IUCV messages 307 * are received and data is copied into buffer @buf up to @count bytes. 308 * 309 * Locking: The routine gets called under an irqsave() spinlock; and 310 * the routine locks the struct hvc_iucv_private->lock to call 311 * helper functions. 312 */ 313 static int hvc_iucv_get_chars(uint32_t vtermno, char *buf, int count) 314 { 315 struct hvc_iucv_private *priv = hvc_iucv_get_private(vtermno); 316 int written; 317 int has_more_data; 318 319 if (count <= 0) 320 return 0; 321 322 if (!priv) 323 return -ENODEV; 324 325 spin_lock(&priv->lock); 326 has_more_data = 0; 327 written = hvc_iucv_write(priv, buf, count, &has_more_data); 328 spin_unlock(&priv->lock); 329 330 /* if there are still messages on the queue... schedule another run */ 331 if (has_more_data) 332 hvc_kick(); 333 334 return written; 335 } 336 337 /** 338 * hvc_iucv_queue() - Buffer terminal data for sending. 339 * @priv: Pointer to struct hvc_iucv_private instance. 340 * @buf: Buffer containing data to send. 341 * @count: Size of buffer and amount of data to send. 342 * 343 * The function queues data for sending. To actually send the buffered data, 344 * a work queue function is scheduled (with QUEUE_SNDBUF_DELAY). 345 * The function returns the number of data bytes that has been buffered. 346 * 347 * If the device is not connected, data is ignored and the function returns 348 * @count. 349 * If the buffer is full, the function returns 0. 350 * If an existing IUCV communicaton path has been severed, -EPIPE is returned 351 * (that can be passed to HVC layer to cause a tty hangup). 352 */ 353 static int hvc_iucv_queue(struct hvc_iucv_private *priv, const char *buf, 354 int count) 355 { 356 size_t len; 357 358 if (priv->iucv_state == IUCV_DISCONN) 359 return count; /* ignore data */ 360 361 if (priv->iucv_state == IUCV_SEVERED) 362 return -EPIPE; 363 364 len = min_t(size_t, count, SNDBUF_SIZE - priv->sndbuf_len); 365 if (!len) 366 return 0; 367 368 memcpy(priv->sndbuf + priv->sndbuf_len, buf, len); 369 priv->sndbuf_len += len; 370 371 if (priv->iucv_state == IUCV_CONNECTED) 372 schedule_delayed_work(&priv->sndbuf_work, QUEUE_SNDBUF_DELAY); 373 374 return len; 375 } 376 377 /** 378 * hvc_iucv_send() - Send an IUCV message containing terminal data. 379 * @priv: Pointer to struct hvc_iucv_private instance. 380 * 381 * If an IUCV communication path has been established, the buffered output data 382 * is sent via an IUCV message and the number of bytes sent is returned. 383 * Returns 0 if there is no established IUCV communication path or 384 * -EPIPE if an existing IUCV communicaton path has been severed. 385 */ 386 static int hvc_iucv_send(struct hvc_iucv_private *priv) 387 { 388 struct iucv_tty_buffer *sb; 389 int rc, len; 390 391 if (priv->iucv_state == IUCV_SEVERED) 392 return -EPIPE; 393 394 if (priv->iucv_state == IUCV_DISCONN) 395 return -EIO; 396 397 if (!priv->sndbuf_len) 398 return 0; 399 400 /* allocate internal buffer to store msg data and also compute total 401 * message length */ 402 sb = alloc_tty_buffer(priv->sndbuf_len, GFP_ATOMIC); 403 if (!sb) 404 return -ENOMEM; 405 406 memcpy(sb->mbuf->data, priv->sndbuf, priv->sndbuf_len); 407 sb->mbuf->datalen = (u16) priv->sndbuf_len; 408 sb->msg.length = MSG_SIZE(sb->mbuf->datalen); 409 410 list_add_tail(&sb->list, &priv->tty_outqueue); 411 412 rc = __iucv_message_send(priv->path, &sb->msg, 0, 0, 413 (void *) sb->mbuf, sb->msg.length); 414 if (rc) { 415 /* drop the message here; however we might want to handle 416 * 0x03 (msg limit reached) by trying again... */ 417 list_del(&sb->list); 418 destroy_tty_buffer(sb); 419 } 420 len = priv->sndbuf_len; 421 priv->sndbuf_len = 0; 422 423 return len; 424 } 425 426 /** 427 * hvc_iucv_sndbuf_work() - Send buffered data over IUCV 428 * @work: Work structure. 429 * 430 * This work queue function sends buffered output data over IUCV and, 431 * if not all buffered data could be sent, reschedules itself. 432 */ 433 static void hvc_iucv_sndbuf_work(struct work_struct *work) 434 { 435 struct hvc_iucv_private *priv; 436 437 priv = container_of(work, struct hvc_iucv_private, sndbuf_work.work); 438 if (!priv) 439 return; 440 441 spin_lock_bh(&priv->lock); 442 hvc_iucv_send(priv); 443 spin_unlock_bh(&priv->lock); 444 } 445 446 /** 447 * hvc_iucv_put_chars() - HVC put_chars operation. 448 * @vtermno: HVC virtual terminal number. 449 * @buf: Pointer to an buffer to read data from 450 * @count: Size of buffer available for reading 451 * 452 * The HVC thread calls this method to write characters to the back-end. 453 * The function calls hvc_iucv_queue() to queue terminal data for sending. 454 * 455 * Locking: The method gets called under an irqsave() spinlock; and 456 * locks struct hvc_iucv_private->lock. 457 */ 458 static int hvc_iucv_put_chars(uint32_t vtermno, const char *buf, int count) 459 { 460 struct hvc_iucv_private *priv = hvc_iucv_get_private(vtermno); 461 int queued; 462 463 if (count <= 0) 464 return 0; 465 466 if (!priv) 467 return -ENODEV; 468 469 spin_lock(&priv->lock); 470 queued = hvc_iucv_queue(priv, buf, count); 471 spin_unlock(&priv->lock); 472 473 return queued; 474 } 475 476 /** 477 * hvc_iucv_notifier_add() - HVC notifier for opening a TTY for the first time. 478 * @hp: Pointer to the HVC device (struct hvc_struct) 479 * @id: Additional data (originally passed to hvc_alloc): the index of an struct 480 * hvc_iucv_private instance. 481 * 482 * The function sets the tty state to TTY_OPENED for the struct hvc_iucv_private 483 * instance that is derived from @id. Always returns 0. 484 * 485 * Locking: struct hvc_iucv_private->lock, spin_lock_bh 486 */ 487 static int hvc_iucv_notifier_add(struct hvc_struct *hp, int id) 488 { 489 struct hvc_iucv_private *priv; 490 491 priv = hvc_iucv_get_private(id); 492 if (!priv) 493 return 0; 494 495 spin_lock_bh(&priv->lock); 496 priv->tty_state = TTY_OPENED; 497 spin_unlock_bh(&priv->lock); 498 499 return 0; 500 } 501 502 /** 503 * hvc_iucv_cleanup() - Clean up and reset a z/VM IUCV HVC instance. 504 * @priv: Pointer to the struct hvc_iucv_private instance. 505 */ 506 static void hvc_iucv_cleanup(struct hvc_iucv_private *priv) 507 { 508 destroy_tty_buffer_list(&priv->tty_outqueue); 509 destroy_tty_buffer_list(&priv->tty_inqueue); 510 511 priv->tty_state = TTY_CLOSED; 512 priv->iucv_state = IUCV_DISCONN; 513 514 priv->sndbuf_len = 0; 515 } 516 517 /** 518 * tty_outqueue_empty() - Test if the tty outq is empty 519 * @priv: Pointer to struct hvc_iucv_private instance. 520 */ 521 static inline int tty_outqueue_empty(struct hvc_iucv_private *priv) 522 { 523 int rc; 524 525 spin_lock_bh(&priv->lock); 526 rc = list_empty(&priv->tty_outqueue); 527 spin_unlock_bh(&priv->lock); 528 529 return rc; 530 } 531 532 /** 533 * flush_sndbuf_sync() - Flush send buffer and wait for completion 534 * @priv: Pointer to struct hvc_iucv_private instance. 535 * 536 * The routine cancels a pending sndbuf work, calls hvc_iucv_send() 537 * to flush any buffered terminal output data and waits for completion. 538 */ 539 static void flush_sndbuf_sync(struct hvc_iucv_private *priv) 540 { 541 int sync_wait; 542 543 cancel_delayed_work_sync(&priv->sndbuf_work); 544 545 spin_lock_bh(&priv->lock); 546 hvc_iucv_send(priv); /* force sending buffered data */ 547 sync_wait = !list_empty(&priv->tty_outqueue); /* anything queued ? */ 548 spin_unlock_bh(&priv->lock); 549 550 if (sync_wait) 551 wait_event_timeout(priv->sndbuf_waitq, 552 tty_outqueue_empty(priv), HZ/10); 553 } 554 555 /** 556 * hvc_iucv_hangup() - Sever IUCV path and schedule hvc tty hang up 557 * @priv: Pointer to hvc_iucv_private structure 558 * 559 * This routine severs an existing IUCV communication path and hangs 560 * up the underlying HVC terminal device. 561 * The hang-up occurs only if an IUCV communication path is established; 562 * otherwise there is no need to hang up the terminal device. 563 * 564 * The IUCV HVC hang-up is separated into two steps: 565 * 1. After the IUCV path has been severed, the iucv_state is set to 566 * IUCV_SEVERED. 567 * 2. Later, when the HVC thread calls hvc_iucv_get_chars(), the 568 * IUCV_SEVERED state causes the tty hang-up in the HVC layer. 569 * 570 * If the tty has not yet been opened, clean up the hvc_iucv_private 571 * structure to allow re-connects. 572 * If the tty has been opened, let get_chars() return -EPIPE to signal 573 * the HVC layer to hang up the tty and, if so, wake up the HVC thread 574 * to call get_chars()... 575 * 576 * Special notes on hanging up a HVC terminal instantiated as console: 577 * Hang-up: 1. do_tty_hangup() replaces file ops (= hung_up_tty_fops) 578 * 2. do_tty_hangup() calls tty->ops->close() for console_filp 579 * => no hangup notifier is called by HVC (default) 580 * 2. hvc_close() returns because of tty_hung_up_p(filp) 581 * => no delete notifier is called! 582 * Finally, the back-end is not being notified, thus, the tty session is 583 * kept active (TTY_OPEN) to be ready for re-connects. 584 * 585 * Locking: spin_lock(&priv->lock) w/o disabling bh 586 */ 587 static void hvc_iucv_hangup(struct hvc_iucv_private *priv) 588 { 589 struct iucv_path *path; 590 591 path = NULL; 592 spin_lock(&priv->lock); 593 if (priv->iucv_state == IUCV_CONNECTED) { 594 path = priv->path; 595 priv->path = NULL; 596 priv->iucv_state = IUCV_SEVERED; 597 if (priv->tty_state == TTY_CLOSED) 598 hvc_iucv_cleanup(priv); 599 else 600 /* console is special (see above) */ 601 if (priv->is_console) { 602 hvc_iucv_cleanup(priv); 603 priv->tty_state = TTY_OPENED; 604 } else 605 hvc_kick(); 606 } 607 spin_unlock(&priv->lock); 608 609 /* finally sever path (outside of priv->lock due to lock ordering) */ 610 if (path) { 611 iucv_path_sever(path, NULL); 612 iucv_path_free(path); 613 } 614 } 615 616 /** 617 * hvc_iucv_notifier_hangup() - HVC notifier for TTY hangups. 618 * @hp: Pointer to the HVC device (struct hvc_struct) 619 * @id: Additional data (originally passed to hvc_alloc): 620 * the index of an struct hvc_iucv_private instance. 621 * 622 * This routine notifies the HVC back-end that a tty hangup (carrier loss, 623 * virtual or otherwise) has occurred. 624 * The z/VM IUCV HVC device driver ignores virtual hangups (vhangup()) 625 * to keep an existing IUCV communication path established. 626 * (Background: vhangup() is called from user space (by getty or login) to 627 * disable writing to the tty by other applications). 628 * If the tty has been opened and an established IUCV path has been severed 629 * (we caused the tty hangup), the function calls hvc_iucv_cleanup(). 630 * 631 * Locking: struct hvc_iucv_private->lock 632 */ 633 static void hvc_iucv_notifier_hangup(struct hvc_struct *hp, int id) 634 { 635 struct hvc_iucv_private *priv; 636 637 priv = hvc_iucv_get_private(id); 638 if (!priv) 639 return; 640 641 flush_sndbuf_sync(priv); 642 643 spin_lock_bh(&priv->lock); 644 /* NOTE: If the hangup was scheduled by ourself (from the iucv 645 * path_servered callback [IUCV_SEVERED]), we have to clean up 646 * our structure and to set state to TTY_CLOSED. 647 * If the tty was hung up otherwise (e.g. vhangup()), then we 648 * ignore this hangup and keep an established IUCV path open... 649 * (...the reason is that we are not able to connect back to the 650 * client if we disconnect on hang up) */ 651 priv->tty_state = TTY_CLOSED; 652 653 if (priv->iucv_state == IUCV_SEVERED) 654 hvc_iucv_cleanup(priv); 655 spin_unlock_bh(&priv->lock); 656 } 657 658 /** 659 * hvc_iucv_dtr_rts() - HVC notifier for handling DTR/RTS 660 * @hp: Pointer the HVC device (struct hvc_struct) 661 * @raise: Non-zero to raise or zero to lower DTR/RTS lines 662 * 663 * This routine notifies the HVC back-end to raise or lower DTR/RTS 664 * lines. Raising DTR/RTS is ignored. Lowering DTR/RTS indicates to 665 * drop the IUCV connection (similar to hang up the modem). 666 */ 667 static void hvc_iucv_dtr_rts(struct hvc_struct *hp, int raise) 668 { 669 struct hvc_iucv_private *priv; 670 struct iucv_path *path; 671 672 /* Raising the DTR/RTS is ignored as IUCV connections can be 673 * established at any times. 674 */ 675 if (raise) 676 return; 677 678 priv = hvc_iucv_get_private(hp->vtermno); 679 if (!priv) 680 return; 681 682 /* Lowering the DTR/RTS lines disconnects an established IUCV 683 * connection. 684 */ 685 flush_sndbuf_sync(priv); 686 687 spin_lock_bh(&priv->lock); 688 path = priv->path; /* save reference to IUCV path */ 689 priv->path = NULL; 690 priv->iucv_state = IUCV_DISCONN; 691 spin_unlock_bh(&priv->lock); 692 693 /* Sever IUCV path outside of priv->lock due to lock ordering of: 694 * priv->lock <--> iucv_table_lock */ 695 if (path) { 696 iucv_path_sever(path, NULL); 697 iucv_path_free(path); 698 } 699 } 700 701 /** 702 * hvc_iucv_notifier_del() - HVC notifier for closing a TTY for the last time. 703 * @hp: Pointer to the HVC device (struct hvc_struct) 704 * @id: Additional data (originally passed to hvc_alloc): 705 * the index of an struct hvc_iucv_private instance. 706 * 707 * This routine notifies the HVC back-end that the last tty device fd has been 708 * closed. The function cleans up tty resources. The clean-up of the IUCV 709 * connection is done in hvc_iucv_dtr_rts() and depends on the HUPCL termios 710 * control setting. 711 * 712 * Locking: struct hvc_iucv_private->lock 713 */ 714 static void hvc_iucv_notifier_del(struct hvc_struct *hp, int id) 715 { 716 struct hvc_iucv_private *priv; 717 718 priv = hvc_iucv_get_private(id); 719 if (!priv) 720 return; 721 722 flush_sndbuf_sync(priv); 723 724 spin_lock_bh(&priv->lock); 725 destroy_tty_buffer_list(&priv->tty_outqueue); 726 destroy_tty_buffer_list(&priv->tty_inqueue); 727 priv->tty_state = TTY_CLOSED; 728 priv->sndbuf_len = 0; 729 spin_unlock_bh(&priv->lock); 730 } 731 732 /** 733 * hvc_iucv_filter_connreq() - Filter connection request based on z/VM user ID 734 * @ipvmid: Originating z/VM user ID (right padded with blanks) 735 * 736 * Returns 0 if the z/VM user ID @ipvmid is allowed to connection, otherwise 737 * non-zero. 738 */ 739 static int hvc_iucv_filter_connreq(u8 ipvmid[8]) 740 { 741 size_t i; 742 743 /* Note: default policy is ACCEPT if no filter is set */ 744 if (!hvc_iucv_filter_size) 745 return 0; 746 747 for (i = 0; i < hvc_iucv_filter_size; i++) 748 if (0 == memcmp(ipvmid, hvc_iucv_filter + (8 * i), 8)) 749 return 0; 750 return 1; 751 } 752 753 /** 754 * hvc_iucv_path_pending() - IUCV handler to process a connection request. 755 * @path: Pending path (struct iucv_path) 756 * @ipvmid: z/VM system identifier of originator 757 * @ipuser: User specified data for this path 758 * (AF_IUCV: port/service name and originator port) 759 * 760 * The function uses the @ipuser data to determine if the pending path belongs 761 * to a terminal managed by this device driver. 762 * If the path belongs to this driver, ensure that the terminal is not accessed 763 * multiple times (only one connection to a terminal is allowed). 764 * If the terminal is not yet connected, the pending path is accepted and is 765 * associated to the appropriate struct hvc_iucv_private instance. 766 * 767 * Returns 0 if @path belongs to a terminal managed by the this device driver; 768 * otherwise returns -ENODEV in order to dispatch this path to other handlers. 769 * 770 * Locking: struct hvc_iucv_private->lock 771 */ 772 static int hvc_iucv_path_pending(struct iucv_path *path, 773 u8 ipvmid[8], u8 ipuser[16]) 774 { 775 struct hvc_iucv_private *priv; 776 u8 nuser_data[16]; 777 u8 vm_user_id[9]; 778 int i, rc; 779 780 priv = NULL; 781 for (i = 0; i < hvc_iucv_devices; i++) 782 if (hvc_iucv_table[i] && 783 (0 == memcmp(hvc_iucv_table[i]->srv_name, ipuser, 8))) { 784 priv = hvc_iucv_table[i]; 785 break; 786 } 787 if (!priv) 788 return -ENODEV; 789 790 /* Enforce that ipvmid is allowed to connect to us */ 791 read_lock(&hvc_iucv_filter_lock); 792 rc = hvc_iucv_filter_connreq(ipvmid); 793 read_unlock(&hvc_iucv_filter_lock); 794 if (rc) { 795 iucv_path_sever(path, ipuser); 796 iucv_path_free(path); 797 memcpy(vm_user_id, ipvmid, 8); 798 vm_user_id[8] = 0; 799 pr_info("A connection request from z/VM user ID %s " 800 "was refused\n", vm_user_id); 801 return 0; 802 } 803 804 spin_lock(&priv->lock); 805 806 /* If the terminal is already connected or being severed, then sever 807 * this path to enforce that there is only ONE established communication 808 * path per terminal. */ 809 if (priv->iucv_state != IUCV_DISCONN) { 810 iucv_path_sever(path, ipuser); 811 iucv_path_free(path); 812 goto out_path_handled; 813 } 814 815 /* accept path */ 816 memcpy(nuser_data, ipuser + 8, 8); /* remote service (for af_iucv) */ 817 memcpy(nuser_data + 8, ipuser, 8); /* local service (for af_iucv) */ 818 path->msglim = 0xffff; /* IUCV MSGLIMIT */ 819 path->flags &= ~IUCV_IPRMDATA; /* TODO: use IUCV_IPRMDATA */ 820 rc = iucv_path_accept(path, &hvc_iucv_handler, nuser_data, priv); 821 if (rc) { 822 iucv_path_sever(path, ipuser); 823 iucv_path_free(path); 824 goto out_path_handled; 825 } 826 priv->path = path; 827 priv->iucv_state = IUCV_CONNECTED; 828 829 /* flush buffered output data... */ 830 schedule_delayed_work(&priv->sndbuf_work, 5); 831 832 out_path_handled: 833 spin_unlock(&priv->lock); 834 return 0; 835 } 836 837 /** 838 * hvc_iucv_path_severed() - IUCV handler to process a path sever. 839 * @path: Pending path (struct iucv_path) 840 * @ipuser: User specified data for this path 841 * (AF_IUCV: port/service name and originator port) 842 * 843 * This function calls the hvc_iucv_hangup() function for the 844 * respective IUCV HVC terminal. 845 * 846 * Locking: struct hvc_iucv_private->lock 847 */ 848 static void hvc_iucv_path_severed(struct iucv_path *path, u8 ipuser[16]) 849 { 850 struct hvc_iucv_private *priv = path->private; 851 852 hvc_iucv_hangup(priv); 853 } 854 855 /** 856 * hvc_iucv_msg_pending() - IUCV handler to process an incoming IUCV message. 857 * @path: Pending path (struct iucv_path) 858 * @msg: Pointer to the IUCV message 859 * 860 * The function puts an incoming message on the input queue for later 861 * processing (by hvc_iucv_get_chars() / hvc_iucv_write()). 862 * If the tty has not yet been opened, the message is rejected. 863 * 864 * Locking: struct hvc_iucv_private->lock 865 */ 866 static void hvc_iucv_msg_pending(struct iucv_path *path, 867 struct iucv_message *msg) 868 { 869 struct hvc_iucv_private *priv = path->private; 870 struct iucv_tty_buffer *rb; 871 872 /* reject messages that exceed max size of iucv_tty_msg->datalen */ 873 if (msg->length > MSG_SIZE(MSG_MAX_DATALEN)) { 874 iucv_message_reject(path, msg); 875 return; 876 } 877 878 spin_lock(&priv->lock); 879 880 /* reject messages if tty has not yet been opened */ 881 if (priv->tty_state == TTY_CLOSED) { 882 iucv_message_reject(path, msg); 883 goto unlock_return; 884 } 885 886 /* allocate tty buffer to save iucv msg only */ 887 rb = alloc_tty_buffer(0, GFP_ATOMIC); 888 if (!rb) { 889 iucv_message_reject(path, msg); 890 goto unlock_return; /* -ENOMEM */ 891 } 892 rb->msg = *msg; 893 894 list_add_tail(&rb->list, &priv->tty_inqueue); 895 896 hvc_kick(); /* wake up hvc thread */ 897 898 unlock_return: 899 spin_unlock(&priv->lock); 900 } 901 902 /** 903 * hvc_iucv_msg_complete() - IUCV handler to process message completion 904 * @path: Pending path (struct iucv_path) 905 * @msg: Pointer to the IUCV message 906 * 907 * The function is called upon completion of message delivery to remove the 908 * message from the outqueue. Additional delivery information can be found 909 * msg->audit: rejected messages (0x040000 (IPADRJCT)), and 910 * purged messages (0x010000 (IPADPGNR)). 911 * 912 * Locking: struct hvc_iucv_private->lock 913 */ 914 static void hvc_iucv_msg_complete(struct iucv_path *path, 915 struct iucv_message *msg) 916 { 917 struct hvc_iucv_private *priv = path->private; 918 struct iucv_tty_buffer *ent, *next; 919 LIST_HEAD(list_remove); 920 921 spin_lock(&priv->lock); 922 list_for_each_entry_safe(ent, next, &priv->tty_outqueue, list) 923 if (ent->msg.id == msg->id) { 924 list_move(&ent->list, &list_remove); 925 break; 926 } 927 wake_up(&priv->sndbuf_waitq); 928 spin_unlock(&priv->lock); 929 destroy_tty_buffer_list(&list_remove); 930 } 931 932 /** 933 * hvc_iucv_pm_freeze() - Freeze PM callback 934 * @dev: IUVC HVC terminal device 935 * 936 * Sever an established IUCV communication path and 937 * trigger a hang-up of the underlying HVC terminal. 938 */ 939 static int hvc_iucv_pm_freeze(struct device *dev) 940 { 941 struct hvc_iucv_private *priv = dev_get_drvdata(dev); 942 943 local_bh_disable(); 944 hvc_iucv_hangup(priv); 945 local_bh_enable(); 946 947 return 0; 948 } 949 950 /** 951 * hvc_iucv_pm_restore_thaw() - Thaw and restore PM callback 952 * @dev: IUVC HVC terminal device 953 * 954 * Wake up the HVC thread to trigger hang-up and respective 955 * HVC back-end notifier invocations. 956 */ 957 static int hvc_iucv_pm_restore_thaw(struct device *dev) 958 { 959 hvc_kick(); 960 return 0; 961 } 962 963 964 /* HVC operations */ 965 static const struct hv_ops hvc_iucv_ops = { 966 .get_chars = hvc_iucv_get_chars, 967 .put_chars = hvc_iucv_put_chars, 968 .notifier_add = hvc_iucv_notifier_add, 969 .notifier_del = hvc_iucv_notifier_del, 970 .notifier_hangup = hvc_iucv_notifier_hangup, 971 .dtr_rts = hvc_iucv_dtr_rts, 972 }; 973 974 /* Suspend / resume device operations */ 975 static const struct dev_pm_ops hvc_iucv_pm_ops = { 976 .freeze = hvc_iucv_pm_freeze, 977 .thaw = hvc_iucv_pm_restore_thaw, 978 .restore = hvc_iucv_pm_restore_thaw, 979 }; 980 981 /* IUCV HVC device driver */ 982 static struct device_driver hvc_iucv_driver = { 983 .name = KMSG_COMPONENT, 984 .bus = &iucv_bus, 985 .pm = &hvc_iucv_pm_ops, 986 }; 987 988 /** 989 * hvc_iucv_alloc() - Allocates a new struct hvc_iucv_private instance 990 * @id: hvc_iucv_table index 991 * @is_console: Flag if the instance is used as Linux console 992 * 993 * This function allocates a new hvc_iucv_private structure and stores 994 * the instance in hvc_iucv_table at index @id. 995 * Returns 0 on success; otherwise non-zero. 996 */ 997 static int __init hvc_iucv_alloc(int id, unsigned int is_console) 998 { 999 struct hvc_iucv_private *priv; 1000 char name[9]; 1001 int rc; 1002 1003 priv = kzalloc(sizeof(struct hvc_iucv_private), GFP_KERNEL); 1004 if (!priv) 1005 return -ENOMEM; 1006 1007 spin_lock_init(&priv->lock); 1008 INIT_LIST_HEAD(&priv->tty_outqueue); 1009 INIT_LIST_HEAD(&priv->tty_inqueue); 1010 INIT_DELAYED_WORK(&priv->sndbuf_work, hvc_iucv_sndbuf_work); 1011 init_waitqueue_head(&priv->sndbuf_waitq); 1012 1013 priv->sndbuf = (void *) get_zeroed_page(GFP_KERNEL); 1014 if (!priv->sndbuf) { 1015 kfree(priv); 1016 return -ENOMEM; 1017 } 1018 1019 /* set console flag */ 1020 priv->is_console = is_console; 1021 1022 /* allocate hvc device */ 1023 priv->hvc = hvc_alloc(HVC_IUCV_MAGIC + id, /* PAGE_SIZE */ 1024 HVC_IUCV_MAGIC + id, &hvc_iucv_ops, 256); 1025 if (IS_ERR(priv->hvc)) { 1026 rc = PTR_ERR(priv->hvc); 1027 goto out_error_hvc; 1028 } 1029 1030 /* notify HVC thread instead of using polling */ 1031 priv->hvc->irq_requested = 1; 1032 1033 /* setup iucv related information */ 1034 snprintf(name, 9, "lnxhvc%-2d", id); 1035 memcpy(priv->srv_name, name, 8); 1036 ASCEBC(priv->srv_name, 8); 1037 1038 /* create and setup device */ 1039 priv->dev = kzalloc(sizeof(*priv->dev), GFP_KERNEL); 1040 if (!priv->dev) { 1041 rc = -ENOMEM; 1042 goto out_error_dev; 1043 } 1044 dev_set_name(priv->dev, "hvc_iucv%d", id); 1045 dev_set_drvdata(priv->dev, priv); 1046 priv->dev->bus = &iucv_bus; 1047 priv->dev->parent = iucv_root; 1048 priv->dev->driver = &hvc_iucv_driver; 1049 priv->dev->release = (void (*)(struct device *)) kfree; 1050 rc = device_register(priv->dev); 1051 if (rc) { 1052 put_device(priv->dev); 1053 goto out_error_dev; 1054 } 1055 1056 hvc_iucv_table[id] = priv; 1057 return 0; 1058 1059 out_error_dev: 1060 hvc_remove(priv->hvc); 1061 out_error_hvc: 1062 free_page((unsigned long) priv->sndbuf); 1063 kfree(priv); 1064 1065 return rc; 1066 } 1067 1068 /** 1069 * hvc_iucv_destroy() - Destroy and free hvc_iucv_private instances 1070 */ 1071 static void __init hvc_iucv_destroy(struct hvc_iucv_private *priv) 1072 { 1073 hvc_remove(priv->hvc); 1074 device_unregister(priv->dev); 1075 free_page((unsigned long) priv->sndbuf); 1076 kfree(priv); 1077 } 1078 1079 /** 1080 * hvc_iucv_parse_filter() - Parse filter for a single z/VM user ID 1081 * @filter: String containing a comma-separated list of z/VM user IDs 1082 */ 1083 static const char *hvc_iucv_parse_filter(const char *filter, char *dest) 1084 { 1085 const char *nextdelim, *residual; 1086 size_t len; 1087 1088 nextdelim = strchr(filter, ','); 1089 if (nextdelim) { 1090 len = nextdelim - filter; 1091 residual = nextdelim + 1; 1092 } else { 1093 len = strlen(filter); 1094 residual = filter + len; 1095 } 1096 1097 if (len == 0) 1098 return ERR_PTR(-EINVAL); 1099 1100 /* check for '\n' (if called from sysfs) */ 1101 if (filter[len - 1] == '\n') 1102 len--; 1103 1104 if (len > 8) 1105 return ERR_PTR(-EINVAL); 1106 1107 /* pad with blanks and save upper case version of user ID */ 1108 memset(dest, ' ', 8); 1109 while (len--) 1110 dest[len] = toupper(filter[len]); 1111 return residual; 1112 } 1113 1114 /** 1115 * hvc_iucv_setup_filter() - Set up z/VM user ID filter 1116 * @filter: String consisting of a comma-separated list of z/VM user IDs 1117 * 1118 * The function parses the @filter string and creates an array containing 1119 * the list of z/VM user ID filter entries. 1120 * Return code 0 means success, -EINVAL if the filter is syntactically 1121 * incorrect, -ENOMEM if there was not enough memory to allocate the 1122 * filter list array, or -ENOSPC if too many z/VM user IDs have been specified. 1123 */ 1124 static int hvc_iucv_setup_filter(const char *val) 1125 { 1126 const char *residual; 1127 int err; 1128 size_t size, count; 1129 void *array, *old_filter; 1130 1131 count = strlen(val); 1132 if (count == 0 || (count == 1 && val[0] == '\n')) { 1133 size = 0; 1134 array = NULL; 1135 goto out_replace_filter; /* clear filter */ 1136 } 1137 1138 /* count user IDs in order to allocate sufficient memory */ 1139 size = 1; 1140 residual = val; 1141 while ((residual = strchr(residual, ',')) != NULL) { 1142 residual++; 1143 size++; 1144 } 1145 1146 /* check if the specified list exceeds the filter limit */ 1147 if (size > MAX_VMID_FILTER) 1148 return -ENOSPC; 1149 1150 array = kzalloc(size * 8, GFP_KERNEL); 1151 if (!array) 1152 return -ENOMEM; 1153 1154 count = size; 1155 residual = val; 1156 while (*residual && count) { 1157 residual = hvc_iucv_parse_filter(residual, 1158 array + ((size - count) * 8)); 1159 if (IS_ERR(residual)) { 1160 err = PTR_ERR(residual); 1161 kfree(array); 1162 goto out_err; 1163 } 1164 count--; 1165 } 1166 1167 out_replace_filter: 1168 write_lock_bh(&hvc_iucv_filter_lock); 1169 old_filter = hvc_iucv_filter; 1170 hvc_iucv_filter_size = size; 1171 hvc_iucv_filter = array; 1172 write_unlock_bh(&hvc_iucv_filter_lock); 1173 kfree(old_filter); 1174 1175 err = 0; 1176 out_err: 1177 return err; 1178 } 1179 1180 /** 1181 * param_set_vmidfilter() - Set z/VM user ID filter parameter 1182 * @val: String consisting of a comma-separated list of z/VM user IDs 1183 * @kp: Kernel parameter pointing to hvc_iucv_filter array 1184 * 1185 * The function sets up the z/VM user ID filter specified as comma-separated 1186 * list of user IDs in @val. 1187 * Note: If it is called early in the boot process, @val is stored and 1188 * parsed later in hvc_iucv_init(). 1189 */ 1190 static int param_set_vmidfilter(const char *val, const struct kernel_param *kp) 1191 { 1192 int rc; 1193 1194 if (!MACHINE_IS_VM || !hvc_iucv_devices) 1195 return -ENODEV; 1196 1197 if (!val) 1198 return -EINVAL; 1199 1200 rc = 0; 1201 if (slab_is_available()) 1202 rc = hvc_iucv_setup_filter(val); 1203 else 1204 hvc_iucv_filter_string = val; /* defer... */ 1205 return rc; 1206 } 1207 1208 /** 1209 * param_get_vmidfilter() - Get z/VM user ID filter 1210 * @buffer: Buffer to store z/VM user ID filter, 1211 * (buffer size assumption PAGE_SIZE) 1212 * @kp: Kernel parameter pointing to the hvc_iucv_filter array 1213 * 1214 * The function stores the filter as a comma-separated list of z/VM user IDs 1215 * in @buffer. Typically, sysfs routines call this function for attr show. 1216 */ 1217 static int param_get_vmidfilter(char *buffer, const struct kernel_param *kp) 1218 { 1219 int rc; 1220 size_t index, len; 1221 void *start, *end; 1222 1223 if (!MACHINE_IS_VM || !hvc_iucv_devices) 1224 return -ENODEV; 1225 1226 rc = 0; 1227 read_lock_bh(&hvc_iucv_filter_lock); 1228 for (index = 0; index < hvc_iucv_filter_size; index++) { 1229 start = hvc_iucv_filter + (8 * index); 1230 end = memchr(start, ' ', 8); 1231 len = (end) ? end - start : 8; 1232 memcpy(buffer + rc, start, len); 1233 rc += len; 1234 buffer[rc++] = ','; 1235 } 1236 read_unlock_bh(&hvc_iucv_filter_lock); 1237 if (rc) 1238 buffer[--rc] = '\0'; /* replace last comma and update rc */ 1239 return rc; 1240 } 1241 1242 #define param_check_vmidfilter(name, p) __param_check(name, p, void) 1243 1244 static struct kernel_param_ops param_ops_vmidfilter = { 1245 .set = param_set_vmidfilter, 1246 .get = param_get_vmidfilter, 1247 }; 1248 1249 /** 1250 * hvc_iucv_init() - z/VM IUCV HVC device driver initialization 1251 */ 1252 static int __init hvc_iucv_init(void) 1253 { 1254 int rc; 1255 unsigned int i; 1256 1257 if (!hvc_iucv_devices) 1258 return -ENODEV; 1259 1260 if (!MACHINE_IS_VM) { 1261 pr_notice("The z/VM IUCV HVC device driver cannot " 1262 "be used without z/VM\n"); 1263 rc = -ENODEV; 1264 goto out_error; 1265 } 1266 1267 if (hvc_iucv_devices > MAX_HVC_IUCV_LINES) { 1268 pr_err("%lu is not a valid value for the hvc_iucv= " 1269 "kernel parameter\n", hvc_iucv_devices); 1270 rc = -EINVAL; 1271 goto out_error; 1272 } 1273 1274 /* register IUCV HVC device driver */ 1275 rc = driver_register(&hvc_iucv_driver); 1276 if (rc) 1277 goto out_error; 1278 1279 /* parse hvc_iucv_allow string and create z/VM user ID filter list */ 1280 if (hvc_iucv_filter_string) { 1281 rc = hvc_iucv_setup_filter(hvc_iucv_filter_string); 1282 switch (rc) { 1283 case 0: 1284 break; 1285 case -ENOMEM: 1286 pr_err("Allocating memory failed with " 1287 "reason code=%d\n", 3); 1288 goto out_error; 1289 case -EINVAL: 1290 pr_err("hvc_iucv_allow= does not specify a valid " 1291 "z/VM user ID list\n"); 1292 goto out_error; 1293 case -ENOSPC: 1294 pr_err("hvc_iucv_allow= specifies too many " 1295 "z/VM user IDs\n"); 1296 goto out_error; 1297 default: 1298 goto out_error; 1299 } 1300 } 1301 1302 hvc_iucv_buffer_cache = kmem_cache_create(KMSG_COMPONENT, 1303 sizeof(struct iucv_tty_buffer), 1304 0, 0, NULL); 1305 if (!hvc_iucv_buffer_cache) { 1306 pr_err("Allocating memory failed with reason code=%d\n", 1); 1307 rc = -ENOMEM; 1308 goto out_error; 1309 } 1310 1311 hvc_iucv_mempool = mempool_create_slab_pool(MEMPOOL_MIN_NR, 1312 hvc_iucv_buffer_cache); 1313 if (!hvc_iucv_mempool) { 1314 pr_err("Allocating memory failed with reason code=%d\n", 2); 1315 kmem_cache_destroy(hvc_iucv_buffer_cache); 1316 rc = -ENOMEM; 1317 goto out_error; 1318 } 1319 1320 /* register the first terminal device as console 1321 * (must be done before allocating hvc terminal devices) */ 1322 rc = hvc_instantiate(HVC_IUCV_MAGIC, IUCV_HVC_CON_IDX, &hvc_iucv_ops); 1323 if (rc) { 1324 pr_err("Registering HVC terminal device as " 1325 "Linux console failed\n"); 1326 goto out_error_memory; 1327 } 1328 1329 /* allocate hvc_iucv_private structs */ 1330 for (i = 0; i < hvc_iucv_devices; i++) { 1331 rc = hvc_iucv_alloc(i, (i == IUCV_HVC_CON_IDX) ? 1 : 0); 1332 if (rc) { 1333 pr_err("Creating a new HVC terminal device " 1334 "failed with error code=%d\n", rc); 1335 goto out_error_hvc; 1336 } 1337 } 1338 1339 /* register IUCV callback handler */ 1340 rc = iucv_register(&hvc_iucv_handler, 0); 1341 if (rc) { 1342 pr_err("Registering IUCV handlers failed with error code=%d\n", 1343 rc); 1344 goto out_error_hvc; 1345 } 1346 1347 return 0; 1348 1349 out_error_hvc: 1350 for (i = 0; i < hvc_iucv_devices; i++) 1351 if (hvc_iucv_table[i]) 1352 hvc_iucv_destroy(hvc_iucv_table[i]); 1353 out_error_memory: 1354 mempool_destroy(hvc_iucv_mempool); 1355 kmem_cache_destroy(hvc_iucv_buffer_cache); 1356 out_error: 1357 kfree(hvc_iucv_filter); 1358 hvc_iucv_devices = 0; /* ensure that we do not provide any device */ 1359 return rc; 1360 } 1361 1362 /** 1363 * hvc_iucv_config() - Parsing of hvc_iucv= kernel command line parameter 1364 * @val: Parameter value (numeric) 1365 */ 1366 static int __init hvc_iucv_config(char *val) 1367 { 1368 return kstrtoul(val, 10, &hvc_iucv_devices); 1369 } 1370 1371 1372 device_initcall(hvc_iucv_init); 1373 __setup("hvc_iucv=", hvc_iucv_config); 1374 core_param(hvc_iucv_allow, hvc_iucv_filter, vmidfilter, 0640); 1375