diff options
Diffstat (limited to 'drivers/tty/hvc/hvc_iucv.c')
-rw-r--r-- | drivers/tty/hvc/hvc_iucv.c | 1337 |
1 files changed, 1337 insertions, 0 deletions
diff --git a/drivers/tty/hvc/hvc_iucv.c b/drivers/tty/hvc/hvc_iucv.c new file mode 100644 index 000000000000..c3425bb3a1f6 --- /dev/null +++ b/drivers/tty/hvc/hvc_iucv.c | |||
@@ -0,0 +1,1337 @@ | |||
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 occured 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 occured. | ||
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_notifier_del() - HVC notifier for closing a TTY for the last time. | ||
660 | * @hp: Pointer to the HVC device (struct hvc_struct) | ||
661 | * @id: Additional data (originally passed to hvc_alloc): | ||
662 | * the index of an struct hvc_iucv_private instance. | ||
663 | * | ||
664 | * This routine notifies the HVC back-end that the last tty device fd has been | ||
665 | * closed. The function calls hvc_iucv_cleanup() to clean up the struct | ||
666 | * hvc_iucv_private instance. | ||
667 | * | ||
668 | * Locking: struct hvc_iucv_private->lock | ||
669 | */ | ||
670 | static void hvc_iucv_notifier_del(struct hvc_struct *hp, int id) | ||
671 | { | ||
672 | struct hvc_iucv_private *priv; | ||
673 | struct iucv_path *path; | ||
674 | |||
675 | priv = hvc_iucv_get_private(id); | ||
676 | if (!priv) | ||
677 | return; | ||
678 | |||
679 | flush_sndbuf_sync(priv); | ||
680 | |||
681 | spin_lock_bh(&priv->lock); | ||
682 | path = priv->path; /* save reference to IUCV path */ | ||
683 | priv->path = NULL; | ||
684 | hvc_iucv_cleanup(priv); | ||
685 | spin_unlock_bh(&priv->lock); | ||
686 | |||
687 | /* sever IUCV path outside of priv->lock due to lock ordering of: | ||
688 | * priv->lock <--> iucv_table_lock */ | ||
689 | if (path) { | ||
690 | iucv_path_sever(path, NULL); | ||
691 | iucv_path_free(path); | ||
692 | } | ||
693 | } | ||
694 | |||
695 | /** | ||
696 | * hvc_iucv_filter_connreq() - Filter connection request based on z/VM user ID | ||
697 | * @ipvmid: Originating z/VM user ID (right padded with blanks) | ||
698 | * | ||
699 | * Returns 0 if the z/VM user ID @ipvmid is allowed to connection, otherwise | ||
700 | * non-zero. | ||
701 | */ | ||
702 | static int hvc_iucv_filter_connreq(u8 ipvmid[8]) | ||
703 | { | ||
704 | size_t i; | ||
705 | |||
706 | /* Note: default policy is ACCEPT if no filter is set */ | ||
707 | if (!hvc_iucv_filter_size) | ||
708 | return 0; | ||
709 | |||
710 | for (i = 0; i < hvc_iucv_filter_size; i++) | ||
711 | if (0 == memcmp(ipvmid, hvc_iucv_filter + (8 * i), 8)) | ||
712 | return 0; | ||
713 | return 1; | ||
714 | } | ||
715 | |||
716 | /** | ||
717 | * hvc_iucv_path_pending() - IUCV handler to process a connection request. | ||
718 | * @path: Pending path (struct iucv_path) | ||
719 | * @ipvmid: z/VM system identifier of originator | ||
720 | * @ipuser: User specified data for this path | ||
721 | * (AF_IUCV: port/service name and originator port) | ||
722 | * | ||
723 | * The function uses the @ipuser data to determine if the pending path belongs | ||
724 | * to a terminal managed by this device driver. | ||
725 | * If the path belongs to this driver, ensure that the terminal is not accessed | ||
726 | * multiple times (only one connection to a terminal is allowed). | ||
727 | * If the terminal is not yet connected, the pending path is accepted and is | ||
728 | * associated to the appropriate struct hvc_iucv_private instance. | ||
729 | * | ||
730 | * Returns 0 if @path belongs to a terminal managed by the this device driver; | ||
731 | * otherwise returns -ENODEV in order to dispatch this path to other handlers. | ||
732 | * | ||
733 | * Locking: struct hvc_iucv_private->lock | ||
734 | */ | ||
735 | static int hvc_iucv_path_pending(struct iucv_path *path, | ||
736 | u8 ipvmid[8], u8 ipuser[16]) | ||
737 | { | ||
738 | struct hvc_iucv_private *priv; | ||
739 | u8 nuser_data[16]; | ||
740 | u8 vm_user_id[9]; | ||
741 | int i, rc; | ||
742 | |||
743 | priv = NULL; | ||
744 | for (i = 0; i < hvc_iucv_devices; i++) | ||
745 | if (hvc_iucv_table[i] && | ||
746 | (0 == memcmp(hvc_iucv_table[i]->srv_name, ipuser, 8))) { | ||
747 | priv = hvc_iucv_table[i]; | ||
748 | break; | ||
749 | } | ||
750 | if (!priv) | ||
751 | return -ENODEV; | ||
752 | |||
753 | /* Enforce that ipvmid is allowed to connect to us */ | ||
754 | read_lock(&hvc_iucv_filter_lock); | ||
755 | rc = hvc_iucv_filter_connreq(ipvmid); | ||
756 | read_unlock(&hvc_iucv_filter_lock); | ||
757 | if (rc) { | ||
758 | iucv_path_sever(path, ipuser); | ||
759 | iucv_path_free(path); | ||
760 | memcpy(vm_user_id, ipvmid, 8); | ||
761 | vm_user_id[8] = 0; | ||
762 | pr_info("A connection request from z/VM user ID %s " | ||
763 | "was refused\n", vm_user_id); | ||
764 | return 0; | ||
765 | } | ||
766 | |||
767 | spin_lock(&priv->lock); | ||
768 | |||
769 | /* If the terminal is already connected or being severed, then sever | ||
770 | * this path to enforce that there is only ONE established communication | ||
771 | * path per terminal. */ | ||
772 | if (priv->iucv_state != IUCV_DISCONN) { | ||
773 | iucv_path_sever(path, ipuser); | ||
774 | iucv_path_free(path); | ||
775 | goto out_path_handled; | ||
776 | } | ||
777 | |||
778 | /* accept path */ | ||
779 | memcpy(nuser_data, ipuser + 8, 8); /* remote service (for af_iucv) */ | ||
780 | memcpy(nuser_data + 8, ipuser, 8); /* local service (for af_iucv) */ | ||
781 | path->msglim = 0xffff; /* IUCV MSGLIMIT */ | ||
782 | path->flags &= ~IUCV_IPRMDATA; /* TODO: use IUCV_IPRMDATA */ | ||
783 | rc = iucv_path_accept(path, &hvc_iucv_handler, nuser_data, priv); | ||
784 | if (rc) { | ||
785 | iucv_path_sever(path, ipuser); | ||
786 | iucv_path_free(path); | ||
787 | goto out_path_handled; | ||
788 | } | ||
789 | priv->path = path; | ||
790 | priv->iucv_state = IUCV_CONNECTED; | ||
791 | |||
792 | /* flush buffered output data... */ | ||
793 | schedule_delayed_work(&priv->sndbuf_work, 5); | ||
794 | |||
795 | out_path_handled: | ||
796 | spin_unlock(&priv->lock); | ||
797 | return 0; | ||
798 | } | ||
799 | |||
800 | /** | ||
801 | * hvc_iucv_path_severed() - IUCV handler to process a path sever. | ||
802 | * @path: Pending path (struct iucv_path) | ||
803 | * @ipuser: User specified data for this path | ||
804 | * (AF_IUCV: port/service name and originator port) | ||
805 | * | ||
806 | * This function calls the hvc_iucv_hangup() function for the | ||
807 | * respective IUCV HVC terminal. | ||
808 | * | ||
809 | * Locking: struct hvc_iucv_private->lock | ||
810 | */ | ||
811 | static void hvc_iucv_path_severed(struct iucv_path *path, u8 ipuser[16]) | ||
812 | { | ||
813 | struct hvc_iucv_private *priv = path->private; | ||
814 | |||
815 | hvc_iucv_hangup(priv); | ||
816 | } | ||
817 | |||
818 | /** | ||
819 | * hvc_iucv_msg_pending() - IUCV handler to process an incoming IUCV message. | ||
820 | * @path: Pending path (struct iucv_path) | ||
821 | * @msg: Pointer to the IUCV message | ||
822 | * | ||
823 | * The function puts an incoming message on the input queue for later | ||
824 | * processing (by hvc_iucv_get_chars() / hvc_iucv_write()). | ||
825 | * If the tty has not yet been opened, the message is rejected. | ||
826 | * | ||
827 | * Locking: struct hvc_iucv_private->lock | ||
828 | */ | ||
829 | static void hvc_iucv_msg_pending(struct iucv_path *path, | ||
830 | struct iucv_message *msg) | ||
831 | { | ||
832 | struct hvc_iucv_private *priv = path->private; | ||
833 | struct iucv_tty_buffer *rb; | ||
834 | |||
835 | /* reject messages that exceed max size of iucv_tty_msg->datalen */ | ||
836 | if (msg->length > MSG_SIZE(MSG_MAX_DATALEN)) { | ||
837 | iucv_message_reject(path, msg); | ||
838 | return; | ||
839 | } | ||
840 | |||
841 | spin_lock(&priv->lock); | ||
842 | |||
843 | /* reject messages if tty has not yet been opened */ | ||
844 | if (priv->tty_state == TTY_CLOSED) { | ||
845 | iucv_message_reject(path, msg); | ||
846 | goto unlock_return; | ||
847 | } | ||
848 | |||
849 | /* allocate tty buffer to save iucv msg only */ | ||
850 | rb = alloc_tty_buffer(0, GFP_ATOMIC); | ||
851 | if (!rb) { | ||
852 | iucv_message_reject(path, msg); | ||
853 | goto unlock_return; /* -ENOMEM */ | ||
854 | } | ||
855 | rb->msg = *msg; | ||
856 | |||
857 | list_add_tail(&rb->list, &priv->tty_inqueue); | ||
858 | |||
859 | hvc_kick(); /* wake up hvc thread */ | ||
860 | |||
861 | unlock_return: | ||
862 | spin_unlock(&priv->lock); | ||
863 | } | ||
864 | |||
865 | /** | ||
866 | * hvc_iucv_msg_complete() - IUCV handler to process message completion | ||
867 | * @path: Pending path (struct iucv_path) | ||
868 | * @msg: Pointer to the IUCV message | ||
869 | * | ||
870 | * The function is called upon completion of message delivery to remove the | ||
871 | * message from the outqueue. Additional delivery information can be found | ||
872 | * msg->audit: rejected messages (0x040000 (IPADRJCT)), and | ||
873 | * purged messages (0x010000 (IPADPGNR)). | ||
874 | * | ||
875 | * Locking: struct hvc_iucv_private->lock | ||
876 | */ | ||
877 | static void hvc_iucv_msg_complete(struct iucv_path *path, | ||
878 | struct iucv_message *msg) | ||
879 | { | ||
880 | struct hvc_iucv_private *priv = path->private; | ||
881 | struct iucv_tty_buffer *ent, *next; | ||
882 | LIST_HEAD(list_remove); | ||
883 | |||
884 | spin_lock(&priv->lock); | ||
885 | list_for_each_entry_safe(ent, next, &priv->tty_outqueue, list) | ||
886 | if (ent->msg.id == msg->id) { | ||
887 | list_move(&ent->list, &list_remove); | ||
888 | break; | ||
889 | } | ||
890 | wake_up(&priv->sndbuf_waitq); | ||
891 | spin_unlock(&priv->lock); | ||
892 | destroy_tty_buffer_list(&list_remove); | ||
893 | } | ||
894 | |||
895 | /** | ||
896 | * hvc_iucv_pm_freeze() - Freeze PM callback | ||
897 | * @dev: IUVC HVC terminal device | ||
898 | * | ||
899 | * Sever an established IUCV communication path and | ||
900 | * trigger a hang-up of the underlying HVC terminal. | ||
901 | */ | ||
902 | static int hvc_iucv_pm_freeze(struct device *dev) | ||
903 | { | ||
904 | struct hvc_iucv_private *priv = dev_get_drvdata(dev); | ||
905 | |||
906 | local_bh_disable(); | ||
907 | hvc_iucv_hangup(priv); | ||
908 | local_bh_enable(); | ||
909 | |||
910 | return 0; | ||
911 | } | ||
912 | |||
913 | /** | ||
914 | * hvc_iucv_pm_restore_thaw() - Thaw and restore PM callback | ||
915 | * @dev: IUVC HVC terminal device | ||
916 | * | ||
917 | * Wake up the HVC thread to trigger hang-up and respective | ||
918 | * HVC back-end notifier invocations. | ||
919 | */ | ||
920 | static int hvc_iucv_pm_restore_thaw(struct device *dev) | ||
921 | { | ||
922 | hvc_kick(); | ||
923 | return 0; | ||
924 | } | ||
925 | |||
926 | |||
927 | /* HVC operations */ | ||
928 | static const struct hv_ops hvc_iucv_ops = { | ||
929 | .get_chars = hvc_iucv_get_chars, | ||
930 | .put_chars = hvc_iucv_put_chars, | ||
931 | .notifier_add = hvc_iucv_notifier_add, | ||
932 | .notifier_del = hvc_iucv_notifier_del, | ||
933 | .notifier_hangup = hvc_iucv_notifier_hangup, | ||
934 | }; | ||
935 | |||
936 | /* Suspend / resume device operations */ | ||
937 | static const struct dev_pm_ops hvc_iucv_pm_ops = { | ||
938 | .freeze = hvc_iucv_pm_freeze, | ||
939 | .thaw = hvc_iucv_pm_restore_thaw, | ||
940 | .restore = hvc_iucv_pm_restore_thaw, | ||
941 | }; | ||
942 | |||
943 | /* IUCV HVC device driver */ | ||
944 | static struct device_driver hvc_iucv_driver = { | ||
945 | .name = KMSG_COMPONENT, | ||
946 | .bus = &iucv_bus, | ||
947 | .pm = &hvc_iucv_pm_ops, | ||
948 | }; | ||
949 | |||
950 | /** | ||
951 | * hvc_iucv_alloc() - Allocates a new struct hvc_iucv_private instance | ||
952 | * @id: hvc_iucv_table index | ||
953 | * @is_console: Flag if the instance is used as Linux console | ||
954 | * | ||
955 | * This function allocates a new hvc_iucv_private structure and stores | ||
956 | * the instance in hvc_iucv_table at index @id. | ||
957 | * Returns 0 on success; otherwise non-zero. | ||
958 | */ | ||
959 | static int __init hvc_iucv_alloc(int id, unsigned int is_console) | ||
960 | { | ||
961 | struct hvc_iucv_private *priv; | ||
962 | char name[9]; | ||
963 | int rc; | ||
964 | |||
965 | priv = kzalloc(sizeof(struct hvc_iucv_private), GFP_KERNEL); | ||
966 | if (!priv) | ||
967 | return -ENOMEM; | ||
968 | |||
969 | spin_lock_init(&priv->lock); | ||
970 | INIT_LIST_HEAD(&priv->tty_outqueue); | ||
971 | INIT_LIST_HEAD(&priv->tty_inqueue); | ||
972 | INIT_DELAYED_WORK(&priv->sndbuf_work, hvc_iucv_sndbuf_work); | ||
973 | init_waitqueue_head(&priv->sndbuf_waitq); | ||
974 | |||
975 | priv->sndbuf = (void *) get_zeroed_page(GFP_KERNEL); | ||
976 | if (!priv->sndbuf) { | ||
977 | kfree(priv); | ||
978 | return -ENOMEM; | ||
979 | } | ||
980 | |||
981 | /* set console flag */ | ||
982 | priv->is_console = is_console; | ||
983 | |||
984 | /* allocate hvc device */ | ||
985 | priv->hvc = hvc_alloc(HVC_IUCV_MAGIC + id, /* PAGE_SIZE */ | ||
986 | HVC_IUCV_MAGIC + id, &hvc_iucv_ops, 256); | ||
987 | if (IS_ERR(priv->hvc)) { | ||
988 | rc = PTR_ERR(priv->hvc); | ||
989 | goto out_error_hvc; | ||
990 | } | ||
991 | |||
992 | /* notify HVC thread instead of using polling */ | ||
993 | priv->hvc->irq_requested = 1; | ||
994 | |||
995 | /* setup iucv related information */ | ||
996 | snprintf(name, 9, "lnxhvc%-2d", id); | ||
997 | memcpy(priv->srv_name, name, 8); | ||
998 | ASCEBC(priv->srv_name, 8); | ||
999 | |||
1000 | /* create and setup device */ | ||
1001 | priv->dev = kzalloc(sizeof(*priv->dev), GFP_KERNEL); | ||
1002 | if (!priv->dev) { | ||
1003 | rc = -ENOMEM; | ||
1004 | goto out_error_dev; | ||
1005 | } | ||
1006 | dev_set_name(priv->dev, "hvc_iucv%d", id); | ||
1007 | dev_set_drvdata(priv->dev, priv); | ||
1008 | priv->dev->bus = &iucv_bus; | ||
1009 | priv->dev->parent = iucv_root; | ||
1010 | priv->dev->driver = &hvc_iucv_driver; | ||
1011 | priv->dev->release = (void (*)(struct device *)) kfree; | ||
1012 | rc = device_register(priv->dev); | ||
1013 | if (rc) { | ||
1014 | put_device(priv->dev); | ||
1015 | goto out_error_dev; | ||
1016 | } | ||
1017 | |||
1018 | hvc_iucv_table[id] = priv; | ||
1019 | return 0; | ||
1020 | |||
1021 | out_error_dev: | ||
1022 | hvc_remove(priv->hvc); | ||
1023 | out_error_hvc: | ||
1024 | free_page((unsigned long) priv->sndbuf); | ||
1025 | kfree(priv); | ||
1026 | |||
1027 | return rc; | ||
1028 | } | ||
1029 | |||
1030 | /** | ||
1031 | * hvc_iucv_destroy() - Destroy and free hvc_iucv_private instances | ||
1032 | */ | ||
1033 | static void __init hvc_iucv_destroy(struct hvc_iucv_private *priv) | ||
1034 | { | ||
1035 | hvc_remove(priv->hvc); | ||
1036 | device_unregister(priv->dev); | ||
1037 | free_page((unsigned long) priv->sndbuf); | ||
1038 | kfree(priv); | ||
1039 | } | ||
1040 | |||
1041 | /** | ||
1042 | * hvc_iucv_parse_filter() - Parse filter for a single z/VM user ID | ||
1043 | * @filter: String containing a comma-separated list of z/VM user IDs | ||
1044 | */ | ||
1045 | static const char *hvc_iucv_parse_filter(const char *filter, char *dest) | ||
1046 | { | ||
1047 | const char *nextdelim, *residual; | ||
1048 | size_t len; | ||
1049 | |||
1050 | nextdelim = strchr(filter, ','); | ||
1051 | if (nextdelim) { | ||
1052 | len = nextdelim - filter; | ||
1053 | residual = nextdelim + 1; | ||
1054 | } else { | ||
1055 | len = strlen(filter); | ||
1056 | residual = filter + len; | ||
1057 | } | ||
1058 | |||
1059 | if (len == 0) | ||
1060 | return ERR_PTR(-EINVAL); | ||
1061 | |||
1062 | /* check for '\n' (if called from sysfs) */ | ||
1063 | if (filter[len - 1] == '\n') | ||
1064 | len--; | ||
1065 | |||
1066 | if (len > 8) | ||
1067 | return ERR_PTR(-EINVAL); | ||
1068 | |||
1069 | /* pad with blanks and save upper case version of user ID */ | ||
1070 | memset(dest, ' ', 8); | ||
1071 | while (len--) | ||
1072 | dest[len] = toupper(filter[len]); | ||
1073 | return residual; | ||
1074 | } | ||
1075 | |||
1076 | /** | ||
1077 | * hvc_iucv_setup_filter() - Set up z/VM user ID filter | ||
1078 | * @filter: String consisting of a comma-separated list of z/VM user IDs | ||
1079 | * | ||
1080 | * The function parses the @filter string and creates an array containing | ||
1081 | * the list of z/VM user ID filter entries. | ||
1082 | * Return code 0 means success, -EINVAL if the filter is syntactically | ||
1083 | * incorrect, -ENOMEM if there was not enough memory to allocate the | ||
1084 | * filter list array, or -ENOSPC if too many z/VM user IDs have been specified. | ||
1085 | */ | ||
1086 | static int hvc_iucv_setup_filter(const char *val) | ||
1087 | { | ||
1088 | const char *residual; | ||
1089 | int err; | ||
1090 | size_t size, count; | ||
1091 | void *array, *old_filter; | ||
1092 | |||
1093 | count = strlen(val); | ||
1094 | if (count == 0 || (count == 1 && val[0] == '\n')) { | ||
1095 | size = 0; | ||
1096 | array = NULL; | ||
1097 | goto out_replace_filter; /* clear filter */ | ||
1098 | } | ||
1099 | |||
1100 | /* count user IDs in order to allocate sufficient memory */ | ||
1101 | size = 1; | ||
1102 | residual = val; | ||
1103 | while ((residual = strchr(residual, ',')) != NULL) { | ||
1104 | residual++; | ||
1105 | size++; | ||
1106 | } | ||
1107 | |||
1108 | /* check if the specified list exceeds the filter limit */ | ||
1109 | if (size > MAX_VMID_FILTER) | ||
1110 | return -ENOSPC; | ||
1111 | |||
1112 | array = kzalloc(size * 8, GFP_KERNEL); | ||
1113 | if (!array) | ||
1114 | return -ENOMEM; | ||
1115 | |||
1116 | count = size; | ||
1117 | residual = val; | ||
1118 | while (*residual && count) { | ||
1119 | residual = hvc_iucv_parse_filter(residual, | ||
1120 | array + ((size - count) * 8)); | ||
1121 | if (IS_ERR(residual)) { | ||
1122 | err = PTR_ERR(residual); | ||
1123 | kfree(array); | ||
1124 | goto out_err; | ||
1125 | } | ||
1126 | count--; | ||
1127 | } | ||
1128 | |||
1129 | out_replace_filter: | ||
1130 | write_lock_bh(&hvc_iucv_filter_lock); | ||
1131 | old_filter = hvc_iucv_filter; | ||
1132 | hvc_iucv_filter_size = size; | ||
1133 | hvc_iucv_filter = array; | ||
1134 | write_unlock_bh(&hvc_iucv_filter_lock); | ||
1135 | kfree(old_filter); | ||
1136 | |||
1137 | err = 0; | ||
1138 | out_err: | ||
1139 | return err; | ||
1140 | } | ||
1141 | |||
1142 | /** | ||
1143 | * param_set_vmidfilter() - Set z/VM user ID filter parameter | ||
1144 | * @val: String consisting of a comma-separated list of z/VM user IDs | ||
1145 | * @kp: Kernel parameter pointing to hvc_iucv_filter array | ||
1146 | * | ||
1147 | * The function sets up the z/VM user ID filter specified as comma-separated | ||
1148 | * list of user IDs in @val. | ||
1149 | * Note: If it is called early in the boot process, @val is stored and | ||
1150 | * parsed later in hvc_iucv_init(). | ||
1151 | */ | ||
1152 | static int param_set_vmidfilter(const char *val, const struct kernel_param *kp) | ||
1153 | { | ||
1154 | int rc; | ||
1155 | |||
1156 | if (!MACHINE_IS_VM || !hvc_iucv_devices) | ||
1157 | return -ENODEV; | ||
1158 | |||
1159 | if (!val) | ||
1160 | return -EINVAL; | ||
1161 | |||
1162 | rc = 0; | ||
1163 | if (slab_is_available()) | ||
1164 | rc = hvc_iucv_setup_filter(val); | ||
1165 | else | ||
1166 | hvc_iucv_filter_string = val; /* defer... */ | ||
1167 | return rc; | ||
1168 | } | ||
1169 | |||
1170 | /** | ||
1171 | * param_get_vmidfilter() - Get z/VM user ID filter | ||
1172 | * @buffer: Buffer to store z/VM user ID filter, | ||
1173 | * (buffer size assumption PAGE_SIZE) | ||
1174 | * @kp: Kernel parameter pointing to the hvc_iucv_filter array | ||
1175 | * | ||
1176 | * The function stores the filter as a comma-separated list of z/VM user IDs | ||
1177 | * in @buffer. Typically, sysfs routines call this function for attr show. | ||
1178 | */ | ||
1179 | static int param_get_vmidfilter(char *buffer, const struct kernel_param *kp) | ||
1180 | { | ||
1181 | int rc; | ||
1182 | size_t index, len; | ||
1183 | void *start, *end; | ||
1184 | |||
1185 | if (!MACHINE_IS_VM || !hvc_iucv_devices) | ||
1186 | return -ENODEV; | ||
1187 | |||
1188 | rc = 0; | ||
1189 | read_lock_bh(&hvc_iucv_filter_lock); | ||
1190 | for (index = 0; index < hvc_iucv_filter_size; index++) { | ||
1191 | start = hvc_iucv_filter + (8 * index); | ||
1192 | end = memchr(start, ' ', 8); | ||
1193 | len = (end) ? end - start : 8; | ||
1194 | memcpy(buffer + rc, start, len); | ||
1195 | rc += len; | ||
1196 | buffer[rc++] = ','; | ||
1197 | } | ||
1198 | read_unlock_bh(&hvc_iucv_filter_lock); | ||
1199 | if (rc) | ||
1200 | buffer[--rc] = '\0'; /* replace last comma and update rc */ | ||
1201 | return rc; | ||
1202 | } | ||
1203 | |||
1204 | #define param_check_vmidfilter(name, p) __param_check(name, p, void) | ||
1205 | |||
1206 | static struct kernel_param_ops param_ops_vmidfilter = { | ||
1207 | .set = param_set_vmidfilter, | ||
1208 | .get = param_get_vmidfilter, | ||
1209 | }; | ||
1210 | |||
1211 | /** | ||
1212 | * hvc_iucv_init() - z/VM IUCV HVC device driver initialization | ||
1213 | */ | ||
1214 | static int __init hvc_iucv_init(void) | ||
1215 | { | ||
1216 | int rc; | ||
1217 | unsigned int i; | ||
1218 | |||
1219 | if (!hvc_iucv_devices) | ||
1220 | return -ENODEV; | ||
1221 | |||
1222 | if (!MACHINE_IS_VM) { | ||
1223 | pr_notice("The z/VM IUCV HVC device driver cannot " | ||
1224 | "be used without z/VM\n"); | ||
1225 | rc = -ENODEV; | ||
1226 | goto out_error; | ||
1227 | } | ||
1228 | |||
1229 | if (hvc_iucv_devices > MAX_HVC_IUCV_LINES) { | ||
1230 | pr_err("%lu is not a valid value for the hvc_iucv= " | ||
1231 | "kernel parameter\n", hvc_iucv_devices); | ||
1232 | rc = -EINVAL; | ||
1233 | goto out_error; | ||
1234 | } | ||
1235 | |||
1236 | /* register IUCV HVC device driver */ | ||
1237 | rc = driver_register(&hvc_iucv_driver); | ||
1238 | if (rc) | ||
1239 | goto out_error; | ||
1240 | |||
1241 | /* parse hvc_iucv_allow string and create z/VM user ID filter list */ | ||
1242 | if (hvc_iucv_filter_string) { | ||
1243 | rc = hvc_iucv_setup_filter(hvc_iucv_filter_string); | ||
1244 | switch (rc) { | ||
1245 | case 0: | ||
1246 | break; | ||
1247 | case -ENOMEM: | ||
1248 | pr_err("Allocating memory failed with " | ||
1249 | "reason code=%d\n", 3); | ||
1250 | goto out_error; | ||
1251 | case -EINVAL: | ||
1252 | pr_err("hvc_iucv_allow= does not specify a valid " | ||
1253 | "z/VM user ID list\n"); | ||
1254 | goto out_error; | ||
1255 | case -ENOSPC: | ||
1256 | pr_err("hvc_iucv_allow= specifies too many " | ||
1257 | "z/VM user IDs\n"); | ||
1258 | goto out_error; | ||
1259 | default: | ||
1260 | goto out_error; | ||
1261 | } | ||
1262 | } | ||
1263 | |||
1264 | hvc_iucv_buffer_cache = kmem_cache_create(KMSG_COMPONENT, | ||
1265 | sizeof(struct iucv_tty_buffer), | ||
1266 | 0, 0, NULL); | ||
1267 | if (!hvc_iucv_buffer_cache) { | ||
1268 | pr_err("Allocating memory failed with reason code=%d\n", 1); | ||
1269 | rc = -ENOMEM; | ||
1270 | goto out_error; | ||
1271 | } | ||
1272 | |||
1273 | hvc_iucv_mempool = mempool_create_slab_pool(MEMPOOL_MIN_NR, | ||
1274 | hvc_iucv_buffer_cache); | ||
1275 | if (!hvc_iucv_mempool) { | ||
1276 | pr_err("Allocating memory failed with reason code=%d\n", 2); | ||
1277 | kmem_cache_destroy(hvc_iucv_buffer_cache); | ||
1278 | rc = -ENOMEM; | ||
1279 | goto out_error; | ||
1280 | } | ||
1281 | |||
1282 | /* register the first terminal device as console | ||
1283 | * (must be done before allocating hvc terminal devices) */ | ||
1284 | rc = hvc_instantiate(HVC_IUCV_MAGIC, IUCV_HVC_CON_IDX, &hvc_iucv_ops); | ||
1285 | if (rc) { | ||
1286 | pr_err("Registering HVC terminal device as " | ||
1287 | "Linux console failed\n"); | ||
1288 | goto out_error_memory; | ||
1289 | } | ||
1290 | |||
1291 | /* allocate hvc_iucv_private structs */ | ||
1292 | for (i = 0; i < hvc_iucv_devices; i++) { | ||
1293 | rc = hvc_iucv_alloc(i, (i == IUCV_HVC_CON_IDX) ? 1 : 0); | ||
1294 | if (rc) { | ||
1295 | pr_err("Creating a new HVC terminal device " | ||
1296 | "failed with error code=%d\n", rc); | ||
1297 | goto out_error_hvc; | ||
1298 | } | ||
1299 | } | ||
1300 | |||
1301 | /* register IUCV callback handler */ | ||
1302 | rc = iucv_register(&hvc_iucv_handler, 0); | ||
1303 | if (rc) { | ||
1304 | pr_err("Registering IUCV handlers failed with error code=%d\n", | ||
1305 | rc); | ||
1306 | goto out_error_hvc; | ||
1307 | } | ||
1308 | |||
1309 | return 0; | ||
1310 | |||
1311 | out_error_hvc: | ||
1312 | for (i = 0; i < hvc_iucv_devices; i++) | ||
1313 | if (hvc_iucv_table[i]) | ||
1314 | hvc_iucv_destroy(hvc_iucv_table[i]); | ||
1315 | out_error_memory: | ||
1316 | mempool_destroy(hvc_iucv_mempool); | ||
1317 | kmem_cache_destroy(hvc_iucv_buffer_cache); | ||
1318 | out_error: | ||
1319 | if (hvc_iucv_filter) | ||
1320 | kfree(hvc_iucv_filter); | ||
1321 | hvc_iucv_devices = 0; /* ensure that we do not provide any device */ | ||
1322 | return rc; | ||
1323 | } | ||
1324 | |||
1325 | /** | ||
1326 | * hvc_iucv_config() - Parsing of hvc_iucv= kernel command line parameter | ||
1327 | * @val: Parameter value (numeric) | ||
1328 | */ | ||
1329 | static int __init hvc_iucv_config(char *val) | ||
1330 | { | ||
1331 | return strict_strtoul(val, 10, &hvc_iucv_devices); | ||
1332 | } | ||
1333 | |||
1334 | |||
1335 | device_initcall(hvc_iucv_init); | ||
1336 | __setup("hvc_iucv=", hvc_iucv_config); | ||
1337 | core_param(hvc_iucv_allow, hvc_iucv_filter, vmidfilter, 0640); | ||