Linux Audio

Check our new training course

Loading...
v6.8
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * IBM ASM Service Processor Device Driver
  4 *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  5 * Copyright (C) IBM Corporation, 2004
  6 *
  7 * Author: Max Asböck <amax@us.ibm.com>
 
  8 */
  9
 10/*
 11 * Parts of this code are based on an article by Jonathan Corbet
 12 * that appeared in Linux Weekly News.
 13 */
 14
 15
 16/*
 17 * The IBMASM file virtual filesystem. It creates the following hierarchy
 18 * dynamically when mounted from user space:
 19 *
 20 *    /ibmasm
 21 *    |-- 0
 22 *    |   |-- command
 23 *    |   |-- event
 24 *    |   |-- reverse_heartbeat
 25 *    |   `-- remote_video
 26 *    |       |-- depth
 27 *    |       |-- height
 28 *    |       `-- width
 29 *    .
 30 *    .
 31 *    .
 32 *    `-- n
 33 *        |-- command
 34 *        |-- event
 35 *        |-- reverse_heartbeat
 36 *        `-- remote_video
 37 *            |-- depth
 38 *            |-- height
 39 *            `-- width
 40 *
 41 * For each service processor the following files are created:
 42 *
 43 * command: execute dot commands
 44 *	write: execute a dot command on the service processor
 45 *	read: return the result of a previously executed dot command
 46 *
 47 * events: listen for service processor events
 48 *	read: sleep (interruptible) until an event occurs
 49 *      write: wakeup sleeping event listener
 50 *
 51 * reverse_heartbeat: send a heartbeat to the service processor
 52 *	read: sleep (interruptible) until the reverse heartbeat fails
 53 *      write: wakeup sleeping heartbeat listener
 54 *
 55 * remote_video/width
 56 * remote_video/height
 57 * remote_video/width: control remote display settings
 58 *	write: set value
 59 *	read: read value
 60 */
 61
 62#include <linux/fs.h>
 63#include <linux/fs_context.h>
 64#include <linux/pagemap.h>
 65#include <linux/slab.h>
 66#include <linux/uaccess.h>
 67#include <asm/io.h>
 68#include "ibmasm.h"
 69#include "remote.h"
 70#include "dot_command.h"
 71
 72#define IBMASMFS_MAGIC 0x66726f67
 73
 74static LIST_HEAD(service_processors);
 75
 76static struct inode *ibmasmfs_make_inode(struct super_block *sb, int mode);
 77static void ibmasmfs_create_files (struct super_block *sb);
 78static int ibmasmfs_fill_super(struct super_block *sb, struct fs_context *fc);
 79
 80static int ibmasmfs_get_tree(struct fs_context *fc)
 81{
 82	return get_tree_single(fc, ibmasmfs_fill_super);
 83}
 84
 85static const struct fs_context_operations ibmasmfs_context_ops = {
 86	.get_tree	= ibmasmfs_get_tree,
 87};
 88
 89static int ibmasmfs_init_fs_context(struct fs_context *fc)
 
 90{
 91	fc->ops = &ibmasmfs_context_ops;
 92	return 0;
 93}
 94
 95static const struct super_operations ibmasmfs_s_ops = {
 96	.statfs		= simple_statfs,
 97	.drop_inode	= generic_delete_inode,
 98};
 99
100static const struct file_operations *ibmasmfs_dir_ops = &simple_dir_operations;
101
102static struct file_system_type ibmasmfs_type = {
103	.owner          = THIS_MODULE,
104	.name           = "ibmasmfs",
105	.init_fs_context = ibmasmfs_init_fs_context,
106	.kill_sb        = kill_litter_super,
107};
108MODULE_ALIAS_FS("ibmasmfs");
109
110static int ibmasmfs_fill_super(struct super_block *sb, struct fs_context *fc)
111{
112	struct inode *root;
113
114	sb->s_blocksize = PAGE_SIZE;
115	sb->s_blocksize_bits = PAGE_SHIFT;
116	sb->s_magic = IBMASMFS_MAGIC;
117	sb->s_op = &ibmasmfs_s_ops;
118	sb->s_time_gran = 1;
119
120	root = ibmasmfs_make_inode (sb, S_IFDIR | 0500);
121	if (!root)
122		return -ENOMEM;
123
124	root->i_op = &simple_dir_inode_operations;
125	root->i_fop = ibmasmfs_dir_ops;
126
127	sb->s_root = d_make_root(root);
128	if (!sb->s_root)
129		return -ENOMEM;
130
131	ibmasmfs_create_files(sb);
132	return 0;
133}
134
135static struct inode *ibmasmfs_make_inode(struct super_block *sb, int mode)
136{
137	struct inode *ret = new_inode(sb);
138
139	if (ret) {
140		ret->i_ino = get_next_ino();
141		ret->i_mode = mode;
142		simple_inode_init_ts(ret);
143	}
144	return ret;
145}
146
147static struct dentry *ibmasmfs_create_file(struct dentry *parent,
 
148			const char *name,
149			const struct file_operations *fops,
150			void *data,
151			int mode)
152{
153	struct dentry *dentry;
154	struct inode *inode;
155
156	dentry = d_alloc_name(parent, name);
157	if (!dentry)
158		return NULL;
159
160	inode = ibmasmfs_make_inode(parent->d_sb, S_IFREG | mode);
161	if (!inode) {
162		dput(dentry);
163		return NULL;
164	}
165
166	inode->i_fop = fops;
167	inode->i_private = data;
168
169	d_add(dentry, inode);
170	return dentry;
171}
172
173static struct dentry *ibmasmfs_create_dir(struct dentry *parent,
 
174				const char *name)
175{
176	struct dentry *dentry;
177	struct inode *inode;
178
179	dentry = d_alloc_name(parent, name);
180	if (!dentry)
181		return NULL;
182
183	inode = ibmasmfs_make_inode(parent->d_sb, S_IFDIR | 0500);
184	if (!inode) {
185		dput(dentry);
186		return NULL;
187	}
188
189	inode->i_op = &simple_dir_inode_operations;
190	inode->i_fop = ibmasmfs_dir_ops;
191
192	d_add(dentry, inode);
193	return dentry;
194}
195
196int ibmasmfs_register(void)
197{
198	return register_filesystem(&ibmasmfs_type);
199}
200
201void ibmasmfs_unregister(void)
202{
203	unregister_filesystem(&ibmasmfs_type);
204}
205
206void ibmasmfs_add_sp(struct service_processor *sp)
207{
208	list_add(&sp->node, &service_processors);
209}
210
211/* struct to save state between command file operations */
212struct ibmasmfs_command_data {
213	struct service_processor	*sp;
214	struct command			*command;
215};
216
217/* struct to save state between event file operations */
218struct ibmasmfs_event_data {
219	struct service_processor	*sp;
220	struct event_reader		reader;
221	int				active;
222};
223
224/* struct to save state between reverse heartbeat file operations */
225struct ibmasmfs_heartbeat_data {
226	struct service_processor	*sp;
227	struct reverse_heartbeat	heartbeat;
228	int				active;
229};
230
231static int command_file_open(struct inode *inode, struct file *file)
232{
233	struct ibmasmfs_command_data *command_data;
234
235	if (!inode->i_private)
236		return -ENODEV;
237
238	command_data = kmalloc(sizeof(struct ibmasmfs_command_data), GFP_KERNEL);
239	if (!command_data)
240		return -ENOMEM;
241
242	command_data->command = NULL;
243	command_data->sp = inode->i_private;
244	file->private_data = command_data;
245	return 0;
246}
247
248static int command_file_close(struct inode *inode, struct file *file)
249{
250	struct ibmasmfs_command_data *command_data = file->private_data;
251
252	if (command_data->command)
253		command_put(command_data->command);
254
255	kfree(command_data);
256	return 0;
257}
258
259static ssize_t command_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
260{
261	struct ibmasmfs_command_data *command_data = file->private_data;
262	struct command *cmd;
263	int len;
264	unsigned long flags;
265
266	if (*offset < 0)
267		return -EINVAL;
268	if (count == 0 || count > IBMASM_CMD_MAX_BUFFER_SIZE)
269		return 0;
270	if (*offset != 0)
271		return 0;
272
273	spin_lock_irqsave(&command_data->sp->lock, flags);
274	cmd = command_data->command;
275	if (cmd == NULL) {
276		spin_unlock_irqrestore(&command_data->sp->lock, flags);
277		return 0;
278	}
279	command_data->command = NULL;
280	spin_unlock_irqrestore(&command_data->sp->lock, flags);
281
282	if (cmd->status != IBMASM_CMD_COMPLETE) {
283		command_put(cmd);
284		return -EIO;
285	}
286	len = min(count, cmd->buffer_size);
287	if (copy_to_user(buf, cmd->buffer, len)) {
288		command_put(cmd);
289		return -EFAULT;
290	}
291	command_put(cmd);
292
293	return len;
294}
295
296static ssize_t command_file_write(struct file *file, const char __user *ubuff, size_t count, loff_t *offset)
297{
298	struct ibmasmfs_command_data *command_data = file->private_data;
299	struct command *cmd;
300	unsigned long flags;
301
302	if (*offset < 0)
303		return -EINVAL;
304	if (count == 0 || count > IBMASM_CMD_MAX_BUFFER_SIZE)
305		return 0;
306	if (*offset != 0)
307		return 0;
308
309	/* commands are executed sequentially, only one command at a time */
310	if (command_data->command)
311		return -EAGAIN;
312
313	cmd = ibmasm_new_command(command_data->sp, count);
314	if (!cmd)
315		return -ENOMEM;
316
317	if (copy_from_user(cmd->buffer, ubuff, count)) {
318		command_put(cmd);
319		return -EFAULT;
320	}
321
322	spin_lock_irqsave(&command_data->sp->lock, flags);
323	if (command_data->command) {
324		spin_unlock_irqrestore(&command_data->sp->lock, flags);
325		command_put(cmd);
326		return -EAGAIN;
327	}
328	command_data->command = cmd;
329	spin_unlock_irqrestore(&command_data->sp->lock, flags);
330
331	ibmasm_exec_command(command_data->sp, cmd);
332	ibmasm_wait_for_response(cmd, get_dot_command_timeout(cmd->buffer));
333
334	return count;
335}
336
337static int event_file_open(struct inode *inode, struct file *file)
338{
339	struct ibmasmfs_event_data *event_data;
340	struct service_processor *sp;
341
342	if (!inode->i_private)
343		return -ENODEV;
344
345	sp = inode->i_private;
346
347	event_data = kmalloc(sizeof(struct ibmasmfs_event_data), GFP_KERNEL);
348	if (!event_data)
349		return -ENOMEM;
350
351	ibmasm_event_reader_register(sp, &event_data->reader);
352
353	event_data->sp = sp;
354	event_data->active = 0;
355	file->private_data = event_data;
356	return 0;
357}
358
359static int event_file_close(struct inode *inode, struct file *file)
360{
361	struct ibmasmfs_event_data *event_data = file->private_data;
362
363	ibmasm_event_reader_unregister(event_data->sp, &event_data->reader);
364	kfree(event_data);
365	return 0;
366}
367
368static ssize_t event_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
369{
370	struct ibmasmfs_event_data *event_data = file->private_data;
371	struct event_reader *reader = &event_data->reader;
372	struct service_processor *sp = event_data->sp;
373	int ret;
374	unsigned long flags;
375
376	if (*offset < 0)
377		return -EINVAL;
378	if (count == 0 || count > IBMASM_EVENT_MAX_SIZE)
379		return 0;
380	if (*offset != 0)
381		return 0;
382
383	spin_lock_irqsave(&sp->lock, flags);
384	if (event_data->active) {
385		spin_unlock_irqrestore(&sp->lock, flags);
386		return -EBUSY;
387	}
388	event_data->active = 1;
389	spin_unlock_irqrestore(&sp->lock, flags);
390
391	ret = ibmasm_get_next_event(sp, reader);
392	if (ret <= 0)
393		goto out;
394
395	if (count < reader->data_size) {
396		ret = -EINVAL;
397		goto out;
398	}
399
400        if (copy_to_user(buf, reader->data, reader->data_size)) {
401		ret = -EFAULT;
402		goto out;
403	}
404	ret = reader->data_size;
405
406out:
407	event_data->active = 0;
408	return ret;
409}
410
411static ssize_t event_file_write(struct file *file, const char __user *buf, size_t count, loff_t *offset)
412{
413	struct ibmasmfs_event_data *event_data = file->private_data;
414
415	if (*offset < 0)
416		return -EINVAL;
417	if (count != 1)
418		return 0;
419	if (*offset != 0)
420		return 0;
421
422	ibmasm_cancel_next_event(&event_data->reader);
423	return 0;
424}
425
426static int r_heartbeat_file_open(struct inode *inode, struct file *file)
427{
428	struct ibmasmfs_heartbeat_data *rhbeat;
429
430	if (!inode->i_private)
431		return -ENODEV;
432
433	rhbeat = kmalloc(sizeof(struct ibmasmfs_heartbeat_data), GFP_KERNEL);
434	if (!rhbeat)
435		return -ENOMEM;
436
437	rhbeat->sp = inode->i_private;
438	rhbeat->active = 0;
439	ibmasm_init_reverse_heartbeat(rhbeat->sp, &rhbeat->heartbeat);
440	file->private_data = rhbeat;
441	return 0;
442}
443
444static int r_heartbeat_file_close(struct inode *inode, struct file *file)
445{
446	struct ibmasmfs_heartbeat_data *rhbeat = file->private_data;
447
448	kfree(rhbeat);
449	return 0;
450}
451
452static ssize_t r_heartbeat_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
453{
454	struct ibmasmfs_heartbeat_data *rhbeat = file->private_data;
455	unsigned long flags;
456	int result;
457
458	if (*offset < 0)
459		return -EINVAL;
460	if (count == 0 || count > 1024)
461		return 0;
462	if (*offset != 0)
463		return 0;
464
465	/* allow only one reverse heartbeat per process */
466	spin_lock_irqsave(&rhbeat->sp->lock, flags);
467	if (rhbeat->active) {
468		spin_unlock_irqrestore(&rhbeat->sp->lock, flags);
469		return -EBUSY;
470	}
471	rhbeat->active = 1;
472	spin_unlock_irqrestore(&rhbeat->sp->lock, flags);
473
474	result = ibmasm_start_reverse_heartbeat(rhbeat->sp, &rhbeat->heartbeat);
475	rhbeat->active = 0;
476
477	return result;
478}
479
480static ssize_t r_heartbeat_file_write(struct file *file, const char __user *buf, size_t count, loff_t *offset)
481{
482	struct ibmasmfs_heartbeat_data *rhbeat = file->private_data;
483
484	if (*offset < 0)
485		return -EINVAL;
486	if (count != 1)
487		return 0;
488	if (*offset != 0)
489		return 0;
490
491	if (rhbeat->active)
492		ibmasm_stop_reverse_heartbeat(&rhbeat->heartbeat);
493
494	return 1;
495}
496
497static int remote_settings_file_close(struct inode *inode, struct file *file)
498{
499	return 0;
500}
501
502static ssize_t remote_settings_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
503{
504	void __iomem *address = (void __iomem *)file->private_data;
 
 
505	int len = 0;
506	unsigned int value;
507	char lbuf[20];
 
 
 
 
 
 
 
 
 
 
508
509	value = readl(address);
510	len = snprintf(lbuf, sizeof(lbuf), "%d\n", value);
511
512	return simple_read_from_buffer(buf, count, offset, lbuf, len);
 
 
 
 
 
 
 
 
 
513}
514
515static ssize_t remote_settings_file_write(struct file *file, const char __user *ubuff, size_t count, loff_t *offset)
516{
517	void __iomem *address = (void __iomem *)file->private_data;
518	char *buff;
519	unsigned int value;
520
521	if (*offset < 0)
522		return -EINVAL;
523	if (count == 0 || count > 1024)
524		return 0;
525	if (*offset != 0)
526		return 0;
527
528	buff = kzalloc (count + 1, GFP_KERNEL);
529	if (!buff)
530		return -ENOMEM;
531
532
533	if (copy_from_user(buff, ubuff, count)) {
534		kfree(buff);
535		return -EFAULT;
536	}
537
538	value = simple_strtoul(buff, NULL, 10);
539	writel(value, address);
540	kfree(buff);
541
542	return count;
543}
544
545static const struct file_operations command_fops = {
546	.open =		command_file_open,
547	.release =	command_file_close,
548	.read =		command_file_read,
549	.write =	command_file_write,
550	.llseek =	generic_file_llseek,
551};
552
553static const struct file_operations event_fops = {
554	.open =		event_file_open,
555	.release =	event_file_close,
556	.read =		event_file_read,
557	.write =	event_file_write,
558	.llseek =	generic_file_llseek,
559};
560
561static const struct file_operations r_heartbeat_fops = {
562	.open =		r_heartbeat_file_open,
563	.release =	r_heartbeat_file_close,
564	.read =		r_heartbeat_file_read,
565	.write =	r_heartbeat_file_write,
566	.llseek =	generic_file_llseek,
567};
568
569static const struct file_operations remote_settings_fops = {
570	.open =		simple_open,
571	.release =	remote_settings_file_close,
572	.read =		remote_settings_file_read,
573	.write =	remote_settings_file_write,
574	.llseek =	generic_file_llseek,
575};
576
577
578static void ibmasmfs_create_files (struct super_block *sb)
579{
580	struct list_head *entry;
581	struct service_processor *sp;
582
583	list_for_each(entry, &service_processors) {
584		struct dentry *dir;
585		struct dentry *remote_dir;
586		sp = list_entry(entry, struct service_processor, node);
587		dir = ibmasmfs_create_dir(sb->s_root, sp->dirname);
588		if (!dir)
589			continue;
590
591		ibmasmfs_create_file(dir, "command", &command_fops, sp, S_IRUSR|S_IWUSR);
592		ibmasmfs_create_file(dir, "event", &event_fops, sp, S_IRUSR|S_IWUSR);
593		ibmasmfs_create_file(dir, "reverse_heartbeat", &r_heartbeat_fops, sp, S_IRUSR|S_IWUSR);
594
595		remote_dir = ibmasmfs_create_dir(dir, "remote_video");
596		if (!remote_dir)
597			continue;
598
599		ibmasmfs_create_file(remote_dir, "width", &remote_settings_fops, (void *)display_width(sp), S_IRUSR|S_IWUSR);
600		ibmasmfs_create_file(remote_dir, "height", &remote_settings_fops, (void *)display_height(sp), S_IRUSR|S_IWUSR);
601		ibmasmfs_create_file(remote_dir, "depth", &remote_settings_fops, (void *)display_depth(sp), S_IRUSR|S_IWUSR);
602	}
603}
v3.5.6
 
  1/*
  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 * dynamically when mounted from user space:
 33 *
 34 *    /ibmasm
 35 *    |-- 0
 36 *    |   |-- command
 37 *    |   |-- event
 38 *    |   |-- reverse_heartbeat
 39 *    |   `-- remote_video
 40 *    |       |-- depth
 41 *    |       |-- height
 42 *    |       `-- width
 43 *    .
 44 *    .
 45 *    .
 46 *    `-- n
 47 *        |-- command
 48 *        |-- event
 49 *        |-- reverse_heartbeat
 50 *        `-- remote_video
 51 *            |-- depth
 52 *            |-- 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
 74 */
 75
 76#include <linux/fs.h>
 
 77#include <linux/pagemap.h>
 78#include <linux/slab.h>
 79#include <asm/uaccess.h>
 80#include <asm/io.h>
 81#include "ibmasm.h"
 82#include "remote.h"
 83#include "dot_command.h"
 84
 85#define IBMASMFS_MAGIC 0x66726f67
 86
 87static LIST_HEAD(service_processors);
 88
 89static struct inode *ibmasmfs_make_inode(struct super_block *sb, int mode);
 90static void ibmasmfs_create_files (struct super_block *sb);
 91static int ibmasmfs_fill_super (struct super_block *sb, void *data, int silent);
 92
 
 
 
 
 
 
 
 
 93
 94static struct dentry *ibmasmfs_mount(struct file_system_type *fst,
 95			int flags, const char *name, void *data)
 96{
 97	return mount_single(fst, flags, data, ibmasmfs_fill_super);
 
 98}
 99
100static const struct super_operations ibmasmfs_s_ops = {
101	.statfs		= simple_statfs,
102	.drop_inode	= generic_delete_inode,
103};
104
105static const struct file_operations *ibmasmfs_dir_ops = &simple_dir_operations;
106
107static struct file_system_type ibmasmfs_type = {
108	.owner          = THIS_MODULE,
109	.name           = "ibmasmfs",
110	.mount          = ibmasmfs_mount,
111	.kill_sb        = kill_litter_super,
112};
 
113
114static int ibmasmfs_fill_super (struct super_block *sb, void *data, int silent)
115{
116	struct inode *root;
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	sb->s_root = d_make_root(root);
132	if (!sb->s_root)
133		return -ENOMEM;
134
135	ibmasmfs_create_files(sb);
136	return 0;
137}
138
139static struct inode *ibmasmfs_make_inode(struct super_block *sb, int mode)
140{
141	struct inode *ret = new_inode(sb);
142
143	if (ret) {
144		ret->i_ino = get_next_ino();
145		ret->i_mode = mode;
146		ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
147	}
148	return ret;
149}
150
151static struct dentry *ibmasmfs_create_file (struct super_block *sb,
152			struct dentry *parent,
153			const char *name,
154			const struct file_operations *fops,
155			void *data,
156			int mode)
157{
158	struct dentry *dentry;
159	struct inode *inode;
160
161	dentry = d_alloc_name(parent, name);
162	if (!dentry)
163		return NULL;
164
165	inode = ibmasmfs_make_inode(sb, S_IFREG | mode);
166	if (!inode) {
167		dput(dentry);
168		return NULL;
169	}
170
171	inode->i_fop = fops;
172	inode->i_private = data;
173
174	d_add(dentry, inode);
175	return dentry;
176}
177
178static struct dentry *ibmasmfs_create_dir (struct super_block *sb,
179				struct dentry *parent,
180				const char *name)
181{
182	struct dentry *dentry;
183	struct inode *inode;
184
185	dentry = d_alloc_name(parent, name);
186	if (!dentry)
187		return NULL;
188
189	inode = ibmasmfs_make_inode(sb, S_IFDIR | 0500);
190	if (!inode) {
191		dput(dentry);
192		return NULL;
193	}
194
195	inode->i_op = &simple_dir_inode_operations;
196	inode->i_fop = ibmasmfs_dir_ops;
197
198	d_add(dentry, inode);
199	return dentry;
200}
201
202int ibmasmfs_register(void)
203{
204	return register_filesystem(&ibmasmfs_type);
205}
206
207void ibmasmfs_unregister(void)
208{
209	unregister_filesystem(&ibmasmfs_type);
210}
211
212void ibmasmfs_add_sp(struct service_processor *sp)
213{
214	list_add(&sp->node, &service_processors);
215}
216
217/* struct to save state between command file operations */
218struct ibmasmfs_command_data {
219	struct service_processor	*sp;
220	struct command			*command;
221};
222
223/* struct to save state between event file operations */
224struct ibmasmfs_event_data {
225	struct service_processor	*sp;
226	struct event_reader		reader;
227	int				active;
228};
229
230/* struct to save state between reverse heartbeat file operations */
231struct ibmasmfs_heartbeat_data {
232	struct service_processor	*sp;
233	struct reverse_heartbeat	heartbeat;
234	int				active;
235};
236
237static int command_file_open(struct inode *inode, struct file *file)
238{
239	struct ibmasmfs_command_data *command_data;
240
241	if (!inode->i_private)
242		return -ENODEV;
243
244	command_data = kmalloc(sizeof(struct ibmasmfs_command_data), GFP_KERNEL);
245	if (!command_data)
246		return -ENOMEM;
247
248	command_data->command = NULL;
249	command_data->sp = inode->i_private;
250	file->private_data = command_data;
251	return 0;
252}
253
254static int command_file_close(struct inode *inode, struct file *file)
255{
256	struct ibmasmfs_command_data *command_data = file->private_data;
257
258	if (command_data->command)
259		command_put(command_data->command);
260
261	kfree(command_data);
262	return 0;
263}
264
265static ssize_t command_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
266{
267	struct ibmasmfs_command_data *command_data = file->private_data;
268	struct command *cmd;
269	int len;
270	unsigned long flags;
271
272	if (*offset < 0)
273		return -EINVAL;
274	if (count == 0 || count > IBMASM_CMD_MAX_BUFFER_SIZE)
275		return 0;
276	if (*offset != 0)
277		return 0;
278
279	spin_lock_irqsave(&command_data->sp->lock, flags);
280	cmd = command_data->command;
281	if (cmd == NULL) {
282		spin_unlock_irqrestore(&command_data->sp->lock, flags);
283		return 0;
284	}
285	command_data->command = NULL;
286	spin_unlock_irqrestore(&command_data->sp->lock, flags);
287
288	if (cmd->status != IBMASM_CMD_COMPLETE) {
289		command_put(cmd);
290		return -EIO;
291	}
292	len = min(count, cmd->buffer_size);
293	if (copy_to_user(buf, cmd->buffer, len)) {
294		command_put(cmd);
295		return -EFAULT;
296	}
297	command_put(cmd);
298
299	return len;
300}
301
302static ssize_t command_file_write(struct file *file, const char __user *ubuff, size_t count, loff_t *offset)
303{
304	struct ibmasmfs_command_data *command_data = file->private_data;
305	struct command *cmd;
306	unsigned long flags;
307
308	if (*offset < 0)
309		return -EINVAL;
310	if (count == 0 || count > IBMASM_CMD_MAX_BUFFER_SIZE)
311		return 0;
312	if (*offset != 0)
313		return 0;
314
315	/* commands are executed sequentially, only one command at a time */
316	if (command_data->command)
317		return -EAGAIN;
318
319	cmd = ibmasm_new_command(command_data->sp, count);
320	if (!cmd)
321		return -ENOMEM;
322
323	if (copy_from_user(cmd->buffer, ubuff, count)) {
324		command_put(cmd);
325		return -EFAULT;
326	}
327
328	spin_lock_irqsave(&command_data->sp->lock, flags);
329	if (command_data->command) {
330		spin_unlock_irqrestore(&command_data->sp->lock, flags);
331		command_put(cmd);
332		return -EAGAIN;
333	}
334	command_data->command = cmd;
335	spin_unlock_irqrestore(&command_data->sp->lock, flags);
336
337	ibmasm_exec_command(command_data->sp, cmd);
338	ibmasm_wait_for_response(cmd, get_dot_command_timeout(cmd->buffer));
339
340	return count;
341}
342
343static int event_file_open(struct inode *inode, struct file *file)
344{
345	struct ibmasmfs_event_data *event_data;
346	struct service_processor *sp;
347
348	if (!inode->i_private)
349		return -ENODEV;
350
351	sp = inode->i_private;
352
353	event_data = kmalloc(sizeof(struct ibmasmfs_event_data), GFP_KERNEL);
354	if (!event_data)
355		return -ENOMEM;
356
357	ibmasm_event_reader_register(sp, &event_data->reader);
358
359	event_data->sp = sp;
360	event_data->active = 0;
361	file->private_data = event_data;
362	return 0;
363}
364
365static int event_file_close(struct inode *inode, struct file *file)
366{
367	struct ibmasmfs_event_data *event_data = file->private_data;
368
369	ibmasm_event_reader_unregister(event_data->sp, &event_data->reader);
370	kfree(event_data);
371	return 0;
372}
373
374static ssize_t event_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
375{
376	struct ibmasmfs_event_data *event_data = file->private_data;
377	struct event_reader *reader = &event_data->reader;
378	struct service_processor *sp = event_data->sp;
379	int ret;
380	unsigned long flags;
381
382	if (*offset < 0)
383		return -EINVAL;
384	if (count == 0 || count > IBMASM_EVENT_MAX_SIZE)
385		return 0;
386	if (*offset != 0)
387		return 0;
388
389	spin_lock_irqsave(&sp->lock, flags);
390	if (event_data->active) {
391		spin_unlock_irqrestore(&sp->lock, flags);
392		return -EBUSY;
393	}
394	event_data->active = 1;
395	spin_unlock_irqrestore(&sp->lock, flags);
396
397	ret = ibmasm_get_next_event(sp, reader);
398	if (ret <= 0)
399		goto out;
400
401	if (count < reader->data_size) {
402		ret = -EINVAL;
403		goto out;
404	}
405
406        if (copy_to_user(buf, reader->data, reader->data_size)) {
407		ret = -EFAULT;
408		goto out;
409	}
410	ret = reader->data_size;
411
412out:
413	event_data->active = 0;
414	return ret;
415}
416
417static ssize_t event_file_write(struct file *file, const char __user *buf, size_t count, loff_t *offset)
418{
419	struct ibmasmfs_event_data *event_data = file->private_data;
420
421	if (*offset < 0)
422		return -EINVAL;
423	if (count != 1)
424		return 0;
425	if (*offset != 0)
426		return 0;
427
428	ibmasm_cancel_next_event(&event_data->reader);
429	return 0;
430}
431
432static int r_heartbeat_file_open(struct inode *inode, struct file *file)
433{
434	struct ibmasmfs_heartbeat_data *rhbeat;
435
436	if (!inode->i_private)
437		return -ENODEV;
438
439	rhbeat = kmalloc(sizeof(struct ibmasmfs_heartbeat_data), GFP_KERNEL);
440	if (!rhbeat)
441		return -ENOMEM;
442
443	rhbeat->sp = inode->i_private;
444	rhbeat->active = 0;
445	ibmasm_init_reverse_heartbeat(rhbeat->sp, &rhbeat->heartbeat);
446	file->private_data = rhbeat;
447	return 0;
448}
449
450static int r_heartbeat_file_close(struct inode *inode, struct file *file)
451{
452	struct ibmasmfs_heartbeat_data *rhbeat = file->private_data;
453
454	kfree(rhbeat);
455	return 0;
456}
457
458static ssize_t r_heartbeat_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
459{
460	struct ibmasmfs_heartbeat_data *rhbeat = file->private_data;
461	unsigned long flags;
462	int result;
463
464	if (*offset < 0)
465		return -EINVAL;
466	if (count == 0 || count > 1024)
467		return 0;
468	if (*offset != 0)
469		return 0;
470
471	/* allow only one reverse heartbeat per process */
472	spin_lock_irqsave(&rhbeat->sp->lock, flags);
473	if (rhbeat->active) {
474		spin_unlock_irqrestore(&rhbeat->sp->lock, flags);
475		return -EBUSY;
476	}
477	rhbeat->active = 1;
478	spin_unlock_irqrestore(&rhbeat->sp->lock, flags);
479
480	result = ibmasm_start_reverse_heartbeat(rhbeat->sp, &rhbeat->heartbeat);
481	rhbeat->active = 0;
482
483	return result;
484}
485
486static ssize_t r_heartbeat_file_write(struct file *file, const char __user *buf, size_t count, loff_t *offset)
487{
488	struct ibmasmfs_heartbeat_data *rhbeat = file->private_data;
489
490	if (*offset < 0)
491		return -EINVAL;
492	if (count != 1)
493		return 0;
494	if (*offset != 0)
495		return 0;
496
497	if (rhbeat->active)
498		ibmasm_stop_reverse_heartbeat(&rhbeat->heartbeat);
499
500	return 1;
501}
502
503static int remote_settings_file_close(struct inode *inode, struct file *file)
504{
505	return 0;
506}
507
508static ssize_t remote_settings_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
509{
510	void __iomem *address = (void __iomem *)file->private_data;
511	unsigned char *page;
512	int retval;
513	int len = 0;
514	unsigned int value;
515
516	if (*offset < 0)
517		return -EINVAL;
518	if (count == 0 || count > 1024)
519		return 0;
520	if (*offset != 0)
521		return 0;
522
523	page = (unsigned char *)__get_free_page(GFP_KERNEL);
524	if (!page)
525		return -ENOMEM;
526
527	value = readl(address);
528	len = sprintf(page, "%d\n", value);
529
530	if (copy_to_user(buf, page, len)) {
531		retval = -EFAULT;
532		goto exit;
533	}
534	*offset += len;
535	retval = len;
536
537exit:
538	free_page((unsigned long)page);
539	return retval;
540}
541
542static ssize_t remote_settings_file_write(struct file *file, const char __user *ubuff, size_t count, loff_t *offset)
543{
544	void __iomem *address = (void __iomem *)file->private_data;
545	char *buff;
546	unsigned int value;
547
548	if (*offset < 0)
549		return -EINVAL;
550	if (count == 0 || count > 1024)
551		return 0;
552	if (*offset != 0)
553		return 0;
554
555	buff = kzalloc (count + 1, GFP_KERNEL);
556	if (!buff)
557		return -ENOMEM;
558
559
560	if (copy_from_user(buff, ubuff, count)) {
561		kfree(buff);
562		return -EFAULT;
563	}
564
565	value = simple_strtoul(buff, NULL, 10);
566	writel(value, address);
567	kfree(buff);
568
569	return count;
570}
571
572static const struct file_operations command_fops = {
573	.open =		command_file_open,
574	.release =	command_file_close,
575	.read =		command_file_read,
576	.write =	command_file_write,
577	.llseek =	generic_file_llseek,
578};
579
580static const struct file_operations event_fops = {
581	.open =		event_file_open,
582	.release =	event_file_close,
583	.read =		event_file_read,
584	.write =	event_file_write,
585	.llseek =	generic_file_llseek,
586};
587
588static const struct file_operations r_heartbeat_fops = {
589	.open =		r_heartbeat_file_open,
590	.release =	r_heartbeat_file_close,
591	.read =		r_heartbeat_file_read,
592	.write =	r_heartbeat_file_write,
593	.llseek =	generic_file_llseek,
594};
595
596static const struct file_operations remote_settings_fops = {
597	.open =		simple_open,
598	.release =	remote_settings_file_close,
599	.read =		remote_settings_file_read,
600	.write =	remote_settings_file_write,
601	.llseek =	generic_file_llseek,
602};
603
604
605static void ibmasmfs_create_files (struct super_block *sb)
606{
607	struct list_head *entry;
608	struct service_processor *sp;
609
610	list_for_each(entry, &service_processors) {
611		struct dentry *dir;
612		struct dentry *remote_dir;
613		sp = list_entry(entry, struct service_processor, node);
614		dir = ibmasmfs_create_dir(sb, sb->s_root, sp->dirname);
615		if (!dir)
616			continue;
617
618		ibmasmfs_create_file(sb, dir, "command", &command_fops, sp, S_IRUSR|S_IWUSR);
619		ibmasmfs_create_file(sb, dir, "event", &event_fops, sp, S_IRUSR|S_IWUSR);
620		ibmasmfs_create_file(sb, dir, "reverse_heartbeat", &r_heartbeat_fops, sp, S_IRUSR|S_IWUSR);
621
622		remote_dir = ibmasmfs_create_dir(sb, dir, "remote_video");
623		if (!remote_dir)
624			continue;
625
626		ibmasmfs_create_file(sb, remote_dir, "width", &remote_settings_fops, (void *)display_width(sp), S_IRUSR|S_IWUSR);
627		ibmasmfs_create_file(sb, remote_dir, "height", &remote_settings_fops, (void *)display_height(sp), S_IRUSR|S_IWUSR);
628		ibmasmfs_create_file(sb, remote_dir, "depth", &remote_settings_fops, (void *)display_depth(sp), S_IRUSR|S_IWUSR);
629	}
630}