Commit | Line | Data |
---|---|---|
44a01d5b | 1 | /* |
17e19f04 | 2 | * hvc_iucv.c - z/VM IUCV hypervisor console (HVC) device driver |
44a01d5b | 3 | * |
17e19f04 | 4 | * This HVC device driver provides terminal access using |
44a01d5b HB |
5 | * z/VM IUCV communication paths. |
6 | * | |
0259162e | 7 | * Copyright IBM Corp. 2008, 2009 |
44a01d5b HB |
8 | * |
9 | * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com> | |
10 | */ | |
11 | #define KMSG_COMPONENT "hvc_iucv" | |
17e19f04 | 12 | #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt |
44a01d5b HB |
13 | |
14 | #include <linux/types.h> | |
5a0e3ad6 | 15 | #include <linux/slab.h> |
44a01d5b | 16 | #include <asm/ebcdic.h> |
431429ff | 17 | #include <linux/ctype.h> |
c45ce4b5 | 18 | #include <linux/delay.h> |
0259162e | 19 | #include <linux/device.h> |
68c6b3d2 | 20 | #include <linux/init.h> |
44a01d5b | 21 | #include <linux/mempool.h> |
431429ff | 22 | #include <linux/moduleparam.h> |
44a01d5b | 23 | #include <linux/tty.h> |
c45ce4b5 | 24 | #include <linux/wait.h> |
44a01d5b HB |
25 | #include <net/iucv/iucv.h> |
26 | ||
27 | #include "hvc_console.h" | |
28 | ||
29 | ||
17e19f04 | 30 | /* General device driver settings */ |
44a01d5b HB |
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 | ||
44a01d5b HB |
43 | struct iucv_tty_msg { |
44 | u8 version; /* Message version */ | |
45 | u8 type; /* Message type */ | |
c45ce4b5 | 46 | #define MSG_MAX_DATALEN ((u16)(~0)) |
44a01d5b HB |
47 | u16 datalen; /* Payload length */ |
48 | u8 data[]; /* Payload buffer */ | |
49 | } __attribute__((packed)); | |
17e19f04 | 50 | #define MSG_SIZE(s) ((s) + offsetof(struct iucv_tty_msg, data)) |
44a01d5b HB |
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 { | |
17e19f04 | 64 | struct hvc_struct *hvc; /* HVC struct reference */ |
44a01d5b | 65 | u8 srv_name[8]; /* IUCV service name (ebcdic) */ |
6c089fd3 | 66 | unsigned char is_console; /* Linux console usage flag */ |
44a01d5b HB |
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 */ | |
c45ce4b5 HB |
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 */ | |
44a01d5b HB |
77 | struct list_head tty_outqueue; /* outgoing IUCV messages */ |
78 | struct list_head tty_inqueue; /* incoming IUCV messages */ | |
0259162e | 79 | struct device *dev; /* device structure */ |
44a01d5b HB |
80 | }; |
81 | ||
82 | struct iucv_tty_buffer { | |
83 | struct list_head list; /* list pointer */ | |
17e19f04 | 84 | struct iucv_message msg; /* store an IUCV message */ |
44a01d5b HB |
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 | ||
2dc184c0 HB |
96 | /* Kernel module parameter: use one terminal device as default */ |
97 | static unsigned long hvc_iucv_devices = 1; | |
44a01d5b HB |
98 | |
99 | /* Array of allocated hvc iucv tty lines... */ | |
100 | static struct hvc_iucv_private *hvc_iucv_table[MAX_HVC_IUCV_LINES]; | |
6c089fd3 | 101 | #define IUCV_HVC_CON_IDX (0) |
431429ff HB |
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); | |
44a01d5b HB |
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 | /** | |
17e19f04 | 137 | * alloc_tty_buffer() - Return a new struct iucv_tty_buffer element. |
44a01d5b HB |
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. | |
91a970d9 HB |
143 | * The internal data buffer is always allocated with GFP_DMA which is |
144 | * required for receiving and sending data with IUCV. | |
44a01d5b HB |
145 | * Note: The total message size arises from the internal buffer size and the |
146 | * members of the iucv_tty_msg structure. | |
44a01d5b HB |
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; | |
6c089fd3 | 156 | memset(bufp, 0, sizeof(*bufp)); |
44a01d5b HB |
157 | |
158 | if (size > 0) { | |
159 | bufp->msg.length = MSG_SIZE(size); | |
91a970d9 | 160 | bufp->mbuf = kmalloc(bufp->msg.length, flags | GFP_DMA); |
44a01d5b HB |
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. | |
44a01d5b HB |
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. | |
17e19f04 | 184 | * @list: List containing struct iucv_tty_buffer elements. |
44a01d5b HB |
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 | /** | |
17e19f04 HB |
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. | |
44a01d5b HB |
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. | |
17e19f04 | 205 | * If the buffer size @count is less than the data message size, the |
44a01d5b | 206 | * message is kept on the input queue and @has_more_data is set to 1. |
17e19f04 | 207 | * If all message data has been written, the message is removed from |
44a01d5b HB |
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 | |
17e19f04 | 214 | * hang up (that is issued by the HVC layer). |
44a01d5b HB |
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 | ||
17e19f04 | 223 | /* immediately return if there is no IUCV connection */ |
44a01d5b HB |
224 | if (priv->iucv_state == IUCV_DISCONN) |
225 | return 0; | |
226 | ||
17e19f04 HB |
227 | /* if the IUCV path has been severed, return -EPIPE to inform the |
228 | * HVC layer to hang up the tty device. */ | |
44a01d5b HB |
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 | ||
17e19f04 | 236 | /* receive an iucv message and flip data to the tty (ldisc) */ |
44a01d5b HB |
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 */ | |
91a970d9 | 243 | rb->mbuf = kmalloc(rb->msg.length, GFP_ATOMIC | GFP_DMA); |
44a01d5b HB |
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 | } | |
25985edc | 258 | /* remove buffer if an error has occurred or received data |
44a01d5b HB |
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; | |
254be490 HB |
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)); | |
44a01d5b HB |
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 | * | |
17e19f04 HB |
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. | |
44a01d5b HB |
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 | /** | |
c45ce4b5 | 338 | * hvc_iucv_queue() - Buffer terminal data for sending. |
44a01d5b HB |
339 | * @priv: Pointer to struct hvc_iucv_private instance. |
340 | * @buf: Buffer containing data to send. | |
c45ce4b5 | 341 | * @count: Size of buffer and amount of data to send. |
44a01d5b | 342 | * |
c45ce4b5 | 343 | * The function queues data for sending. To actually send the buffered data, |
17e19f04 | 344 | * a work queue function is scheduled (with QUEUE_SNDBUF_DELAY). |
c45ce4b5 | 345 | * The function returns the number of data bytes that has been buffered. |
44a01d5b | 346 | * |
c45ce4b5 HB |
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. | |
17e19f04 HB |
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). | |
44a01d5b | 352 | */ |
c45ce4b5 | 353 | static int hvc_iucv_queue(struct hvc_iucv_private *priv, const char *buf, |
17e19f04 | 354 | int count) |
c45ce4b5 HB |
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 | * | |
17e19f04 HB |
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. | |
c45ce4b5 HB |
385 | */ |
386 | static int hvc_iucv_send(struct hvc_iucv_private *priv) | |
44a01d5b HB |
387 | { |
388 | struct iucv_tty_buffer *sb; | |
c45ce4b5 | 389 | int rc, len; |
44a01d5b HB |
390 | |
391 | if (priv->iucv_state == IUCV_SEVERED) | |
392 | return -EPIPE; | |
393 | ||
394 | if (priv->iucv_state == IUCV_DISCONN) | |
c45ce4b5 | 395 | return -EIO; |
44a01d5b | 396 | |
c45ce4b5 HB |
397 | if (!priv->sndbuf_len) |
398 | return 0; | |
44a01d5b HB |
399 | |
400 | /* allocate internal buffer to store msg data and also compute total | |
401 | * message length */ | |
c45ce4b5 | 402 | sb = alloc_tty_buffer(priv->sndbuf_len, GFP_ATOMIC); |
44a01d5b HB |
403 | if (!sb) |
404 | return -ENOMEM; | |
405 | ||
c45ce4b5 HB |
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); | |
44a01d5b HB |
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) { | |
c45ce4b5 HB |
415 | /* drop the message here; however we might want to handle |
416 | * 0x03 (msg limit reached) by trying again... */ | |
44a01d5b HB |
417 | list_del(&sb->list); |
418 | destroy_tty_buffer(sb); | |
44a01d5b | 419 | } |
c45ce4b5 HB |
420 | len = priv->sndbuf_len; |
421 | priv->sndbuf_len = 0; | |
44a01d5b HB |
422 | |
423 | return len; | |
424 | } | |
425 | ||
c45ce4b5 HB |
426 | /** |
427 | * hvc_iucv_sndbuf_work() - Send buffered data over IUCV | |
428 | * @work: Work structure. | |
429 | * | |
17e19f04 HB |
430 | * This work queue function sends buffered output data over IUCV and, |
431 | * if not all buffered data could be sent, reschedules itself. | |
c45ce4b5 HB |
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); | |
c45ce4b5 HB |
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 | ||
44a01d5b HB |
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 | * | |
17e19f04 HB |
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. | |
44a01d5b HB |
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); | |
c45ce4b5 | 461 | int queued; |
44a01d5b HB |
462 | |
463 | if (count <= 0) | |
464 | return 0; | |
465 | ||
466 | if (!priv) | |
467 | return -ENODEV; | |
468 | ||
469 | spin_lock(&priv->lock); | |
c45ce4b5 | 470 | queued = hvc_iucv_queue(priv, buf, count); |
44a01d5b HB |
471 | spin_unlock(&priv->lock); |
472 | ||
c45ce4b5 | 473 | return queued; |
44a01d5b HB |
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 | * | |
6c089fd3 | 482 | * The function sets the tty state to TTY_OPENED for the struct hvc_iucv_private |
44a01d5b HB |
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 | /** | |
17e19f04 | 503 | * hvc_iucv_cleanup() - Clean up and reset a z/VM IUCV HVC instance. |
44a01d5b | 504 | * @priv: Pointer to the struct hvc_iucv_private instance. |
44a01d5b HB |
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; | |
c45ce4b5 HB |
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, | |
0259162e HB |
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 | } | |
44a01d5b HB |
614 | } |
615 | ||
616 | /** | |
17e19f04 HB |
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. | |
44a01d5b | 621 | * |
17e19f04 | 622 | * This routine notifies the HVC back-end that a tty hangup (carrier loss, |
25985edc | 623 | * virtual or otherwise) has occurred. |
17e19f04 HB |
624 | * The z/VM IUCV HVC device driver ignores virtual hangups (vhangup()) |
625 | * to keep an existing IUCV communication path established. | |
44a01d5b HB |
626 | * (Background: vhangup() is called from user space (by getty or login) to |
627 | * disable writing to the tty by other applications). | |
17e19f04 HB |
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(). | |
44a01d5b HB |
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 | ||
c45ce4b5 HB |
641 | flush_sndbuf_sync(priv); |
642 | ||
44a01d5b HB |
643 | spin_lock_bh(&priv->lock); |
644 | /* NOTE: If the hangup was scheduled by ourself (from the iucv | |
17e19f04 HB |
645 | * path_servered callback [IUCV_SEVERED]), we have to clean up |
646 | * our structure and to set state to TTY_CLOSED. | |
44a01d5b HB |
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 | ||
74b3b4cd HB |
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 | ||
44a01d5b HB |
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 | * | |
17e19f04 | 707 | * This routine notifies the HVC back-end that the last tty device fd has been |
74b3b4cd HB |
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. | |
44a01d5b HB |
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; | |
44a01d5b HB |
717 | |
718 | priv = hvc_iucv_get_private(id); | |
719 | if (!priv) | |
720 | return; | |
721 | ||
c45ce4b5 HB |
722 | flush_sndbuf_sync(priv); |
723 | ||
44a01d5b | 724 | spin_lock_bh(&priv->lock); |
74b3b4cd HB |
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; | |
44a01d5b | 729 | spin_unlock_bh(&priv->lock); |
44a01d5b HB |
730 | } |
731 | ||
431429ff HB |
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 | ||
44a01d5b HB |
753 | /** |
754 | * hvc_iucv_path_pending() - IUCV handler to process a connection request. | |
755 | * @path: Pending path (struct iucv_path) | |
17e19f04 | 756 | * @ipvmid: z/VM system identifier of originator |
44a01d5b HB |
757 | * @ipuser: User specified data for this path |
758 | * (AF_IUCV: port/service name and originator port) | |
759 | * | |
17e19f04 HB |
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. | |
44a01d5b | 766 | * |
17e19f04 | 767 | * Returns 0 if @path belongs to a terminal managed by the this device driver; |
44a01d5b HB |
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]; | |
431429ff | 777 | u8 vm_user_id[9]; |
44a01d5b HB |
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 | } | |
44a01d5b HB |
787 | if (!priv) |
788 | return -ENODEV; | |
789 | ||
431429ff HB |
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 | ||
44a01d5b HB |
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 | ||
c45ce4b5 HB |
829 | /* flush buffered output data... */ |
830 | schedule_delayed_work(&priv->sndbuf_work, 5); | |
831 | ||
44a01d5b HB |
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 | * | |
0259162e HB |
843 | * This function calls the hvc_iucv_hangup() function for the |
844 | * respective IUCV HVC terminal. | |
44a01d5b HB |
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 | ||
0259162e | 852 | hvc_iucv_hangup(priv); |
44a01d5b HB |
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 | * | |
17e19f04 | 860 | * The function puts an incoming message on the input queue for later |
44a01d5b | 861 | * processing (by hvc_iucv_get_chars() / hvc_iucv_write()). |
17e19f04 | 862 | * If the tty has not yet been opened, the message is rejected. |
44a01d5b HB |
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 | ||
c45ce4b5 HB |
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 | ||
44a01d5b HB |
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 | ||
c45ce4b5 | 886 | /* allocate tty buffer to save iucv msg only */ |
44a01d5b HB |
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 | ||
17e19f04 | 896 | hvc_kick(); /* wake up hvc thread */ |
44a01d5b HB |
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 | * | |
17e19f04 HB |
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)). | |
44a01d5b HB |
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 | } | |
c45ce4b5 | 927 | wake_up(&priv->sndbuf_waitq); |
44a01d5b HB |
928 | spin_unlock(&priv->lock); |
929 | destroy_tty_buffer_list(&list_remove); | |
930 | } | |
931 | ||
0259162e HB |
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 | ||
44a01d5b HB |
963 | |
964 | /* HVC operations */ | |
1dff3996 | 965 | static const struct hv_ops hvc_iucv_ops = { |
44a01d5b HB |
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, | |
74b3b4cd | 971 | .dtr_rts = hvc_iucv_dtr_rts, |
44a01d5b HB |
972 | }; |
973 | ||
0259162e | 974 | /* Suspend / resume device operations */ |
47145210 | 975 | static const struct dev_pm_ops hvc_iucv_pm_ops = { |
0259162e HB |
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 | ||
44a01d5b HB |
988 | /** |
989 | * hvc_iucv_alloc() - Allocates a new struct hvc_iucv_private instance | |
6c089fd3 HB |
990 | * @id: hvc_iucv_table index |
991 | * @is_console: Flag if the instance is used as Linux console | |
44a01d5b | 992 | * |
17e19f04 HB |
993 | * This function allocates a new hvc_iucv_private structure and stores |
994 | * the instance in hvc_iucv_table at index @id. | |
44a01d5b HB |
995 | * Returns 0 on success; otherwise non-zero. |
996 | */ | |
6c089fd3 | 997 | static int __init hvc_iucv_alloc(int id, unsigned int is_console) |
44a01d5b HB |
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); | |
c45ce4b5 HB |
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 | } | |
44a01d5b | 1018 | |
6c089fd3 HB |
1019 | /* set console flag */ |
1020 | priv->is_console = is_console; | |
1021 | ||
0259162e | 1022 | /* allocate hvc device */ |
c45ce4b5 HB |
1023 | priv->hvc = hvc_alloc(HVC_IUCV_MAGIC + id, /* PAGE_SIZE */ |
1024 | HVC_IUCV_MAGIC + id, &hvc_iucv_ops, 256); | |
44a01d5b HB |
1025 | if (IS_ERR(priv->hvc)) { |
1026 | rc = PTR_ERR(priv->hvc); | |
0259162e | 1027 | goto out_error_hvc; |
44a01d5b HB |
1028 | } |
1029 | ||
17e19f04 | 1030 | /* notify HVC thread instead of using polling */ |
c45ce4b5 HB |
1031 | priv->hvc->irq_requested = 1; |
1032 | ||
44a01d5b | 1033 | /* setup iucv related information */ |
2dc184c0 | 1034 | snprintf(name, 9, "lnxhvc%-2d", id); |
44a01d5b HB |
1035 | memcpy(priv->srv_name, name, 8); |
1036 | ASCEBC(priv->srv_name, 8); | |
1037 | ||
0259162e HB |
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) { | |
c6304933 | 1052 | put_device(priv->dev); |
0259162e HB |
1053 | goto out_error_dev; |
1054 | } | |
1055 | ||
44a01d5b HB |
1056 | hvc_iucv_table[id] = priv; |
1057 | return 0; | |
0259162e HB |
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); | |
44a01d5b HB |
1077 | } |
1078 | ||
431429ff HB |
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 | */ | |
549a8a03 | 1190 | static int param_set_vmidfilter(const char *val, const struct kernel_param *kp) |
431429ff HB |
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 | */ | |
549a8a03 | 1217 | static int param_get_vmidfilter(char *buffer, const struct kernel_param *kp) |
431429ff HB |
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 | ||
549a8a03 SS |
1244 | static struct kernel_param_ops param_ops_vmidfilter = { |
1245 | .set = param_set_vmidfilter, | |
1246 | .get = param_get_vmidfilter, | |
1247 | }; | |
1248 | ||
44a01d5b | 1249 | /** |
17e19f04 | 1250 | * hvc_iucv_init() - z/VM IUCV HVC device driver initialization |
44a01d5b HB |
1251 | */ |
1252 | static int __init hvc_iucv_init(void) | |
1253 | { | |
6c089fd3 HB |
1254 | int rc; |
1255 | unsigned int i; | |
44a01d5b | 1256 | |
431429ff HB |
1257 | if (!hvc_iucv_devices) |
1258 | return -ENODEV; | |
1259 | ||
44a01d5b | 1260 | if (!MACHINE_IS_VM) { |
82f3a79b | 1261 | pr_notice("The z/VM IUCV HVC device driver cannot " |
c45ce4b5 | 1262 | "be used without z/VM\n"); |
431429ff HB |
1263 | rc = -ENODEV; |
1264 | goto out_error; | |
44a01d5b HB |
1265 | } |
1266 | ||
82f3a79b HB |
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); | |
431429ff HB |
1270 | rc = -EINVAL; |
1271 | goto out_error; | |
1272 | } | |
1273 | ||
0259162e HB |
1274 | /* register IUCV HVC device driver */ |
1275 | rc = driver_register(&hvc_iucv_driver); | |
1276 | if (rc) | |
1277 | goto out_error; | |
1278 | ||
431429ff HB |
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 | } | |
82f3a79b | 1300 | } |
44a01d5b HB |
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) { | |
c45ce4b5 | 1306 | pr_err("Allocating memory failed with reason code=%d\n", 1); |
431429ff HB |
1307 | rc = -ENOMEM; |
1308 | goto out_error; | |
44a01d5b HB |
1309 | } |
1310 | ||
1311 | hvc_iucv_mempool = mempool_create_slab_pool(MEMPOOL_MIN_NR, | |
1312 | hvc_iucv_buffer_cache); | |
1313 | if (!hvc_iucv_mempool) { | |
c45ce4b5 | 1314 | pr_err("Allocating memory failed with reason code=%d\n", 2); |
44a01d5b | 1315 | kmem_cache_destroy(hvc_iucv_buffer_cache); |
431429ff HB |
1316 | rc = -ENOMEM; |
1317 | goto out_error; | |
44a01d5b HB |
1318 | } |
1319 | ||
68c6b3d2 HB |
1320 | /* register the first terminal device as console |
1321 | * (must be done before allocating hvc terminal devices) */ | |
6c089fd3 HB |
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 | } | |
68c6b3d2 | 1328 | |
44a01d5b HB |
1329 | /* allocate hvc_iucv_private structs */ |
1330 | for (i = 0; i < hvc_iucv_devices; i++) { | |
6c089fd3 | 1331 | rc = hvc_iucv_alloc(i, (i == IUCV_HVC_CON_IDX) ? 1 : 0); |
44a01d5b | 1332 | if (rc) { |
c45ce4b5 | 1333 | pr_err("Creating a new HVC terminal device " |
17e19f04 | 1334 | "failed with error code=%d\n", rc); |
44a01d5b HB |
1335 | goto out_error_hvc; |
1336 | } | |
1337 | } | |
1338 | ||
1339 | /* register IUCV callback handler */ | |
1340 | rc = iucv_register(&hvc_iucv_handler, 0); | |
1341 | if (rc) { | |
c45ce4b5 HB |
1342 | pr_err("Registering IUCV handlers failed with error code=%d\n", |
1343 | rc); | |
c77f7cf7 | 1344 | goto out_error_hvc; |
44a01d5b HB |
1345 | } |
1346 | ||
1347 | return 0; | |
1348 | ||
44a01d5b HB |
1349 | out_error_hvc: |
1350 | for (i = 0; i < hvc_iucv_devices; i++) | |
0259162e HB |
1351 | if (hvc_iucv_table[i]) |
1352 | hvc_iucv_destroy(hvc_iucv_table[i]); | |
6c089fd3 | 1353 | out_error_memory: |
44a01d5b HB |
1354 | mempool_destroy(hvc_iucv_mempool); |
1355 | kmem_cache_destroy(hvc_iucv_buffer_cache); | |
431429ff | 1356 | out_error: |
0259162e HB |
1357 | if (hvc_iucv_filter) |
1358 | kfree(hvc_iucv_filter); | |
431429ff | 1359 | hvc_iucv_devices = 0; /* ensure that we do not provide any device */ |
44a01d5b HB |
1360 | return rc; |
1361 | } | |
1362 | ||
44a01d5b HB |
1363 | /** |
1364 | * hvc_iucv_config() - Parsing of hvc_iucv= kernel command line parameter | |
1365 | * @val: Parameter value (numeric) | |
1366 | */ | |
1367 | static int __init hvc_iucv_config(char *val) | |
1368 | { | |
86b40567 | 1369 | return kstrtoul(val, 10, &hvc_iucv_devices); |
44a01d5b HB |
1370 | } |
1371 | ||
1372 | ||
68c6b3d2 | 1373 | device_initcall(hvc_iucv_init); |
44a01d5b | 1374 | __setup("hvc_iucv=", hvc_iucv_config); |
431429ff | 1375 | core_param(hvc_iucv_allow, hvc_iucv_filter, vmidfilter, 0640); |