blob: 5c550fcac2c487f176ba6a2881d41d1449423a15 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * IBM ASM Service Processor Device Driver
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
17 *
18 * Copyright (C) IBM Corporation, 2004
19 *
20 * Author: Max Asböck <amax@us.ibm.com>
21 *
22 */
23
24/*
25 * Parts of this code are based on an article by Jonathan Corbet
26 * that appeared in Linux Weekly News.
27 */
28
29
30/*
31 * The IBMASM file virtual filesystem. It creates the following hierarchy
32 * dymamically when mounted from user space:
33 *
34 * /ibmasm
35 * |-- 0
36 * | |-- command
37 * | |-- event
38 * | |-- reverse_heartbeat
39 * | `-- remote_video
Linus Torvalds1da177e2005-04-16 15:20:36 -070040 * | |-- depth
Linus Torvalds1da177e2005-04-16 15:20:36 -070041 * | |-- height
42 * | `-- width
43 * .
44 * .
45 * .
46 * `-- n
47 * |-- command
48 * |-- event
49 * |-- reverse_heartbeat
50 * `-- remote_video
Linus Torvalds1da177e2005-04-16 15:20:36 -070051 * |-- depth
Linus Torvalds1da177e2005-04-16 15:20:36 -070052 * |-- height
53 * `-- width
54 *
55 * For each service processor the following files are created:
56 *
57 * command: execute dot commands
58 * write: execute a dot command on the service processor
59 * read: return the result of a previously executed dot command
60 *
61 * events: listen for service processor events
62 * read: sleep (interruptible) until an event occurs
63 * write: wakeup sleeping event listener
64 *
65 * reverse_heartbeat: send a heartbeat to the service processor
66 * read: sleep (interruptible) until the reverse heartbeat fails
67 * write: wakeup sleeping heartbeat listener
68 *
69 * remote_video/width
70 * remote_video/height
71 * remote_video/width: control remote display settings
72 * write: set value
73 * read: read value
Linus Torvalds1da177e2005-04-16 15:20:36 -070074 */
75
76#include <linux/fs.h>
77#include <linux/pagemap.h>
78#include <asm/uaccess.h>
79#include <asm/io.h>
80#include "ibmasm.h"
81#include "remote.h"
82#include "dot_command.h"
83
84#define IBMASMFS_MAGIC 0x66726f67
85
86static LIST_HEAD(service_processors);
87
88static struct inode *ibmasmfs_make_inode(struct super_block *sb, int mode);
89static void ibmasmfs_create_files (struct super_block *sb, struct dentry *root);
90static int ibmasmfs_fill_super (struct super_block *sb, void *data, int silent);
91
92
93static struct super_block *ibmasmfs_get_super(struct file_system_type *fst,
94 int flags, const char *name, void *data)
95{
96 return get_sb_single(fst, flags, data, ibmasmfs_fill_super);
97}
98
99static struct super_operations ibmasmfs_s_ops = {
100 .statfs = simple_statfs,
101 .drop_inode = generic_delete_inode,
102};
103
104static struct file_operations *ibmasmfs_dir_ops = &simple_dir_operations;
105
106static struct file_system_type ibmasmfs_type = {
107 .owner = THIS_MODULE,
108 .name = "ibmasmfs",
109 .get_sb = ibmasmfs_get_super,
110 .kill_sb = kill_litter_super,
111};
112
113static int ibmasmfs_fill_super (struct super_block *sb, void *data, int silent)
114{
115 struct inode *root;
116 struct dentry *root_dentry;
117
118 sb->s_blocksize = PAGE_CACHE_SIZE;
119 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
120 sb->s_magic = IBMASMFS_MAGIC;
121 sb->s_op = &ibmasmfs_s_ops;
122 sb->s_time_gran = 1;
123
124 root = ibmasmfs_make_inode (sb, S_IFDIR | 0500);
125 if (!root)
126 return -ENOMEM;
127
128 root->i_op = &simple_dir_inode_operations;
129 root->i_fop = ibmasmfs_dir_ops;
130
131 root_dentry = d_alloc_root(root);
132 if (!root_dentry) {
133 iput(root);
134 return -ENOMEM;
135 }
136 sb->s_root = root_dentry;
137
138 ibmasmfs_create_files(sb, root_dentry);
139 return 0;
140}
141
142static struct inode *ibmasmfs_make_inode(struct super_block *sb, int mode)
143{
144 struct inode *ret = new_inode(sb);
145
146 if (ret) {
147 ret->i_mode = mode;
148 ret->i_uid = ret->i_gid = 0;
149 ret->i_blksize = PAGE_CACHE_SIZE;
150 ret->i_blocks = 0;
151 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
152 }
153 return ret;
154}
155
156static struct dentry *ibmasmfs_create_file (struct super_block *sb,
157 struct dentry *parent,
158 const char *name,
159 struct file_operations *fops,
160 void *data,
161 int mode)
162{
163 struct dentry *dentry;
164 struct inode *inode;
165
166 dentry = d_alloc_name(parent, name);
167 if (!dentry)
168 return NULL;
169
170 inode = ibmasmfs_make_inode(sb, S_IFREG | mode);
171 if (!inode) {
172 dput(dentry);
173 return NULL;
174 }
175
176 inode->i_fop = fops;
177 inode->u.generic_ip = data;
178
179 d_add(dentry, inode);
180 return dentry;
181}
182
183static struct dentry *ibmasmfs_create_dir (struct super_block *sb,
184 struct dentry *parent,
185 const char *name)
186{
187 struct dentry *dentry;
188 struct inode *inode;
189
190 dentry = d_alloc_name(parent, name);
191 if (!dentry)
192 return NULL;
193
194 inode = ibmasmfs_make_inode(sb, S_IFDIR | 0500);
195 if (!inode) {
196 dput(dentry);
197 return NULL;
198 }
199
200 inode->i_op = &simple_dir_inode_operations;
201 inode->i_fop = ibmasmfs_dir_ops;
202
203 d_add(dentry, inode);
204 return dentry;
205}
206
207int ibmasmfs_register(void)
208{
209 return register_filesystem(&ibmasmfs_type);
210}
211
212void ibmasmfs_unregister(void)
213{
214 unregister_filesystem(&ibmasmfs_type);
215}
216
217void ibmasmfs_add_sp(struct service_processor *sp)
218{
219 list_add(&sp->node, &service_processors);
220}
221
222/* struct to save state between command file operations */
223struct ibmasmfs_command_data {
224 struct service_processor *sp;
225 struct command *command;
226};
227
228/* struct to save state between event file operations */
229struct ibmasmfs_event_data {
230 struct service_processor *sp;
231 struct event_reader reader;
232 int active;
233};
234
235/* struct to save state between reverse heartbeat file operations */
236struct ibmasmfs_heartbeat_data {
237 struct service_processor *sp;
238 struct reverse_heartbeat heartbeat;
239 int active;
240};
241
242static int command_file_open(struct inode *inode, struct file *file)
243{
244 struct ibmasmfs_command_data *command_data;
245
246 if (!inode->u.generic_ip)
247 return -ENODEV;
248
249 command_data = kmalloc(sizeof(struct ibmasmfs_command_data), GFP_KERNEL);
250 if (!command_data)
251 return -ENOMEM;
252
253 command_data->command = NULL;
254 command_data->sp = inode->u.generic_ip;
255 file->private_data = command_data;
256 return 0;
257}
258
259static int command_file_close(struct inode *inode, struct file *file)
260{
261 struct ibmasmfs_command_data *command_data = file->private_data;
262
263 if (command_data->command)
264 command_put(command_data->command);
265
266 kfree(command_data);
267 return 0;
268}
269
270static ssize_t command_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
271{
272 struct ibmasmfs_command_data *command_data = file->private_data;
273 struct command *cmd;
274 int len;
275 unsigned long flags;
276
277 if (*offset < 0)
278 return -EINVAL;
279 if (count == 0 || count > IBMASM_CMD_MAX_BUFFER_SIZE)
280 return 0;
281 if (*offset != 0)
282 return 0;
283
284 spin_lock_irqsave(&command_data->sp->lock, flags);
285 cmd = command_data->command;
286 if (cmd == NULL) {
287 spin_unlock_irqrestore(&command_data->sp->lock, flags);
288 return 0;
289 }
290 command_data->command = NULL;
291 spin_unlock_irqrestore(&command_data->sp->lock, flags);
292
293 if (cmd->status != IBMASM_CMD_COMPLETE) {
294 command_put(cmd);
295 return -EIO;
296 }
297 len = min(count, cmd->buffer_size);
298 if (copy_to_user(buf, cmd->buffer, len)) {
299 command_put(cmd);
300 return -EFAULT;
301 }
302 command_put(cmd);
303
304 return len;
305}
306
307static ssize_t command_file_write(struct file *file, const char __user *ubuff, size_t count, loff_t *offset)
308{
309 struct ibmasmfs_command_data *command_data = file->private_data;
310 struct command *cmd;
311 unsigned long flags;
312
313 if (*offset < 0)
314 return -EINVAL;
315 if (count == 0 || count > IBMASM_CMD_MAX_BUFFER_SIZE)
316 return 0;
317 if (*offset != 0)
318 return 0;
319
320 /* commands are executed sequentially, only one command at a time */
321 if (command_data->command)
322 return -EAGAIN;
323
Max Asbock88187602005-06-21 17:16:36 -0700324 cmd = ibmasm_new_command(command_data->sp, count);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325 if (!cmd)
326 return -ENOMEM;
327
328 if (copy_from_user(cmd->buffer, ubuff, count)) {
329 command_put(cmd);
330 return -EFAULT;
331 }
332
333 spin_lock_irqsave(&command_data->sp->lock, flags);
334 if (command_data->command) {
335 spin_unlock_irqrestore(&command_data->sp->lock, flags);
336 command_put(cmd);
337 return -EAGAIN;
338 }
339 command_data->command = cmd;
340 spin_unlock_irqrestore(&command_data->sp->lock, flags);
341
342 ibmasm_exec_command(command_data->sp, cmd);
343 ibmasm_wait_for_response(cmd, get_dot_command_timeout(cmd->buffer));
344
345 return count;
346}
347
348static int event_file_open(struct inode *inode, struct file *file)
349{
350 struct ibmasmfs_event_data *event_data;
351 struct service_processor *sp;
352
353 if (!inode->u.generic_ip)
354 return -ENODEV;
355
356 sp = inode->u.generic_ip;
357
358 event_data = kmalloc(sizeof(struct ibmasmfs_event_data), GFP_KERNEL);
359 if (!event_data)
360 return -ENOMEM;
361
362 ibmasm_event_reader_register(sp, &event_data->reader);
363
364 event_data->sp = sp;
Max Asbockb8acb802005-06-21 17:16:33 -0700365 event_data->active = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366 file->private_data = event_data;
367 return 0;
368}
369
370static int event_file_close(struct inode *inode, struct file *file)
371{
372 struct ibmasmfs_event_data *event_data = file->private_data;
373
374 ibmasm_event_reader_unregister(event_data->sp, &event_data->reader);
375 kfree(event_data);
376 return 0;
377}
378
379static ssize_t event_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
380{
381 struct ibmasmfs_event_data *event_data = file->private_data;
382 struct event_reader *reader = &event_data->reader;
Max Asbockb8acb802005-06-21 17:16:33 -0700383 struct service_processor *sp = event_data->sp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384 int ret;
Max Asbockb8acb802005-06-21 17:16:33 -0700385 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386
387 if (*offset < 0)
388 return -EINVAL;
389 if (count == 0 || count > IBMASM_EVENT_MAX_SIZE)
390 return 0;
391 if (*offset != 0)
392 return 0;
393
Max Asbockb8acb802005-06-21 17:16:33 -0700394 spin_lock_irqsave(&sp->lock, flags);
395 if (event_data->active) {
396 spin_unlock_irqrestore(&sp->lock, flags);
397 return -EBUSY;
398 }
399 event_data->active = 1;
400 spin_unlock_irqrestore(&sp->lock, flags);
401
402 ret = ibmasm_get_next_event(sp, reader);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 if (ret <= 0)
Max Asbockb8acb802005-06-21 17:16:33 -0700404 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405
Max Asbockb8acb802005-06-21 17:16:33 -0700406 if (count < reader->data_size) {
407 ret = -EINVAL;
408 goto out;
409 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410
Max Asbockb8acb802005-06-21 17:16:33 -0700411 if (copy_to_user(buf, reader->data, reader->data_size)) {
412 ret = -EFAULT;
413 goto out;
414 }
415 ret = reader->data_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416
Max Asbockb8acb802005-06-21 17:16:33 -0700417out:
418 event_data->active = 0;
419 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420}
421
422static ssize_t event_file_write(struct file *file, const char __user *buf, size_t count, loff_t *offset)
423{
424 struct ibmasmfs_event_data *event_data = file->private_data;
425
426 if (*offset < 0)
427 return -EINVAL;
428 if (count != 1)
429 return 0;
430 if (*offset != 0)
431 return 0;
432
Max Asbockb8acb802005-06-21 17:16:33 -0700433 ibmasm_cancel_next_event(&event_data->reader);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434 return 0;
435}
436
437static int r_heartbeat_file_open(struct inode *inode, struct file *file)
438{
439 struct ibmasmfs_heartbeat_data *rhbeat;
440
441 if (!inode->u.generic_ip)
442 return -ENODEV;
443
444 rhbeat = kmalloc(sizeof(struct ibmasmfs_heartbeat_data), GFP_KERNEL);
445 if (!rhbeat)
446 return -ENOMEM;
447
448 rhbeat->sp = (struct service_processor *)inode->u.generic_ip;
449 rhbeat->active = 0;
450 ibmasm_init_reverse_heartbeat(rhbeat->sp, &rhbeat->heartbeat);
451 file->private_data = rhbeat;
452 return 0;
453}
454
455static int r_heartbeat_file_close(struct inode *inode, struct file *file)
456{
457 struct ibmasmfs_heartbeat_data *rhbeat = file->private_data;
458
459 kfree(rhbeat);
460 return 0;
461}
462
463static ssize_t r_heartbeat_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
464{
465 struct ibmasmfs_heartbeat_data *rhbeat = file->private_data;
466 unsigned long flags;
467 int result;
468
469 if (*offset < 0)
470 return -EINVAL;
471 if (count == 0 || count > 1024)
472 return 0;
473 if (*offset != 0)
474 return 0;
475
476 /* allow only one reverse heartbeat per process */
477 spin_lock_irqsave(&rhbeat->sp->lock, flags);
478 if (rhbeat->active) {
479 spin_unlock_irqrestore(&rhbeat->sp->lock, flags);
480 return -EBUSY;
481 }
482 rhbeat->active = 1;
483 spin_unlock_irqrestore(&rhbeat->sp->lock, flags);
484
485 result = ibmasm_start_reverse_heartbeat(rhbeat->sp, &rhbeat->heartbeat);
486 rhbeat->active = 0;
487
488 return result;
489}
490
491static ssize_t r_heartbeat_file_write(struct file *file, const char __user *buf, size_t count, loff_t *offset)
492{
493 struct ibmasmfs_heartbeat_data *rhbeat = file->private_data;
494
495 if (*offset < 0)
496 return -EINVAL;
497 if (count != 1)
498 return 0;
499 if (*offset != 0)
500 return 0;
501
502 if (rhbeat->active)
503 ibmasm_stop_reverse_heartbeat(&rhbeat->heartbeat);
504
505 return 1;
506}
507
508static int remote_settings_file_open(struct inode *inode, struct file *file)
509{
510 file->private_data = inode->u.generic_ip;
511 return 0;
512}
513
514static int remote_settings_file_close(struct inode *inode, struct file *file)
515{
516 return 0;
517}
518
519static ssize_t remote_settings_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
520{
521 void __iomem *address = (void __iomem *)file->private_data;
522 unsigned char *page;
523 int retval;
524 int len = 0;
525 unsigned int value;
526
527 if (*offset < 0)
528 return -EINVAL;
529 if (count == 0 || count > 1024)
530 return 0;
531 if (*offset != 0)
532 return 0;
533
534 page = (unsigned char *)__get_free_page(GFP_KERNEL);
535 if (!page)
536 return -ENOMEM;
537
538 value = readl(address);
539 len = sprintf(page, "%d\n", value);
540
541 if (copy_to_user(buf, page, len)) {
542 retval = -EFAULT;
543 goto exit;
544 }
545 *offset += len;
546 retval = len;
547
548exit:
549 free_page((unsigned long)page);
550 return retval;
551}
552
553static ssize_t remote_settings_file_write(struct file *file, const char __user *ubuff, size_t count, loff_t *offset)
554{
555 void __iomem *address = (void __iomem *)file->private_data;
556 char *buff;
557 unsigned int value;
558
559 if (*offset < 0)
560 return -EINVAL;
561 if (count == 0 || count > 1024)
562 return 0;
563 if (*offset != 0)
564 return 0;
565
566 buff = kmalloc (count + 1, GFP_KERNEL);
567 if (!buff)
568 return -ENOMEM;
569
570 memset(buff, 0x0, count + 1);
571
572 if (copy_from_user(buff, ubuff, count)) {
573 kfree(buff);
574 return -EFAULT;
575 }
576
577 value = simple_strtoul(buff, NULL, 10);
578 writel(value, address);
579 kfree(buff);
580
581 return count;
582}
583
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584static struct file_operations command_fops = {
585 .open = command_file_open,
586 .release = command_file_close,
587 .read = command_file_read,
588 .write = command_file_write,
589};
590
591static struct file_operations event_fops = {
592 .open = event_file_open,
593 .release = event_file_close,
594 .read = event_file_read,
595 .write = event_file_write,
596};
597
598static struct file_operations r_heartbeat_fops = {
599 .open = r_heartbeat_file_open,
600 .release = r_heartbeat_file_close,
601 .read = r_heartbeat_file_read,
602 .write = r_heartbeat_file_write,
603};
604
605static struct file_operations remote_settings_fops = {
606 .open = remote_settings_file_open,
607 .release = remote_settings_file_close,
608 .read = remote_settings_file_read,
609 .write = remote_settings_file_write,
610};
611
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612
613static void ibmasmfs_create_files (struct super_block *sb, struct dentry *root)
614{
615 struct list_head *entry;
616 struct service_processor *sp;
617
618 list_for_each(entry, &service_processors) {
619 struct dentry *dir;
620 struct dentry *remote_dir;
621 sp = list_entry(entry, struct service_processor, node);
622 dir = ibmasmfs_create_dir(sb, root, sp->dirname);
623 if (!dir)
624 continue;
625
626 ibmasmfs_create_file(sb, dir, "command", &command_fops, sp, S_IRUSR|S_IWUSR);
627 ibmasmfs_create_file(sb, dir, "event", &event_fops, sp, S_IRUSR|S_IWUSR);
628 ibmasmfs_create_file(sb, dir, "reverse_heartbeat", &r_heartbeat_fops, sp, S_IRUSR|S_IWUSR);
629
630 remote_dir = ibmasmfs_create_dir(sb, dir, "remote_video");
631 if (!remote_dir)
632 continue;
633
634 ibmasmfs_create_file(sb, remote_dir, "width", &remote_settings_fops, (void *)display_width(sp), S_IRUSR|S_IWUSR);
635 ibmasmfs_create_file(sb, remote_dir, "height", &remote_settings_fops, (void *)display_height(sp), S_IRUSR|S_IWUSR);
636 ibmasmfs_create_file(sb, remote_dir, "depth", &remote_settings_fops, (void *)display_depth(sp), S_IRUSR|S_IWUSR);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637 }
638}