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Note: File does not exist in v3.1.
  1/*
  2 *
  3 * Intel Management Engine Interface (Intel MEI) Linux driver
  4 * Copyright (c) 2003-2012, Intel Corporation.
  5 *
  6 * This program is free software; you can redistribute it and/or modify it
  7 * under the terms and conditions of the GNU General Public License,
  8 * version 2, as published by the Free Software Foundation.
  9 *
 10 * This program is distributed in the hope it will be useful, but WITHOUT
 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 13 * more details.
 14 *
 15 */
 16#include <linux/module.h>
 17#include <linux/moduleparam.h>
 18#include <linux/kernel.h>
 19#include <linux/device.h>
 20#include <linux/fs.h>
 21#include <linux/errno.h>
 22#include <linux/types.h>
 23#include <linux/fcntl.h>
 24#include <linux/aio.h>
 25#include <linux/pci.h>
 26#include <linux/poll.h>
 27#include <linux/init.h>
 28#include <linux/ioctl.h>
 29#include <linux/cdev.h>
 30#include <linux/sched.h>
 31#include <linux/uuid.h>
 32#include <linux/compat.h>
 33#include <linux/jiffies.h>
 34#include <linux/interrupt.h>
 35#include <linux/miscdevice.h>
 36
 37#include <linux/mei.h>
 38
 39#include "mei_dev.h"
 40#include "client.h"
 41
 42/**
 43 * mei_open - the open function
 44 *
 45 * @inode: pointer to inode structure
 46 * @file: pointer to file structure
 47 *
 48 * returns 0 on success, <0 on error
 49 */
 50static int mei_open(struct inode *inode, struct file *file)
 51{
 52	struct miscdevice *misc = file->private_data;
 53	struct pci_dev *pdev;
 54	struct mei_cl *cl;
 55	struct mei_device *dev;
 56
 57	int err;
 58
 59	if (!misc->parent)
 60		return -ENODEV;
 61
 62	pdev = container_of(misc->parent, struct pci_dev, dev);
 63
 64	dev = pci_get_drvdata(pdev);
 65	if (!dev)
 66		return -ENODEV;
 67
 68	mutex_lock(&dev->device_lock);
 69
 70	cl = NULL;
 71
 72	err = -ENODEV;
 73	if (dev->dev_state != MEI_DEV_ENABLED) {
 74		dev_dbg(&dev->pdev->dev, "dev_state != MEI_ENABLED  dev_state = %s\n",
 75		    mei_dev_state_str(dev->dev_state));
 76		goto err_unlock;
 77	}
 78
 79	err = -ENOMEM;
 80	cl = mei_cl_allocate(dev);
 81	if (!cl)
 82		goto err_unlock;
 83
 84	/* open_handle_count check is handled in the mei_cl_link */
 85	err = mei_cl_link(cl, MEI_HOST_CLIENT_ID_ANY);
 86	if (err)
 87		goto err_unlock;
 88
 89	file->private_data = cl;
 90
 91	mutex_unlock(&dev->device_lock);
 92
 93	return nonseekable_open(inode, file);
 94
 95err_unlock:
 96	mutex_unlock(&dev->device_lock);
 97	kfree(cl);
 98	return err;
 99}
100
101/**
102 * mei_release - the release function
103 *
104 * @inode: pointer to inode structure
105 * @file: pointer to file structure
106 *
107 * returns 0 on success, <0 on error
108 */
109static int mei_release(struct inode *inode, struct file *file)
110{
111	struct mei_cl *cl = file->private_data;
112	struct mei_cl_cb *cb;
113	struct mei_device *dev;
114	int rets = 0;
115
116	if (WARN_ON(!cl || !cl->dev))
117		return -ENODEV;
118
119	dev = cl->dev;
120
121	mutex_lock(&dev->device_lock);
122	if (cl == &dev->iamthif_cl) {
123		rets = mei_amthif_release(dev, file);
124		goto out;
125	}
126	if (cl->state == MEI_FILE_CONNECTED) {
127		cl->state = MEI_FILE_DISCONNECTING;
128		cl_dbg(dev, cl, "disconnecting\n");
129		rets = mei_cl_disconnect(cl);
130	}
131	mei_cl_flush_queues(cl);
132	cl_dbg(dev, cl, "removing\n");
133
134	mei_cl_unlink(cl);
135
136
137	/* free read cb */
138	cb = NULL;
139	if (cl->read_cb) {
140		cb = mei_cl_find_read_cb(cl);
141		/* Remove entry from read list */
142		if (cb)
143			list_del(&cb->list);
144
145		cb = cl->read_cb;
146		cl->read_cb = NULL;
147	}
148
149	file->private_data = NULL;
150
151	mei_io_cb_free(cb);
152
153	kfree(cl);
154out:
155	mutex_unlock(&dev->device_lock);
156	return rets;
157}
158
159
160/**
161 * mei_read - the read function.
162 *
163 * @file: pointer to file structure
164 * @ubuf: pointer to user buffer
165 * @length: buffer length
166 * @offset: data offset in buffer
167 *
168 * returns >=0 data length on success , <0 on error
169 */
170static ssize_t mei_read(struct file *file, char __user *ubuf,
171			size_t length, loff_t *offset)
172{
173	struct mei_cl *cl = file->private_data;
174	struct mei_cl_cb *cb_pos = NULL;
175	struct mei_cl_cb *cb = NULL;
176	struct mei_device *dev;
177	int rets;
178	int err;
179
180
181	if (WARN_ON(!cl || !cl->dev))
182		return -ENODEV;
183
184	dev = cl->dev;
185
186
187	mutex_lock(&dev->device_lock);
188	if (dev->dev_state != MEI_DEV_ENABLED) {
189		rets = -ENODEV;
190		goto out;
191	}
192
193	if (length == 0) {
194		rets = 0;
195		goto out;
196	}
197
198	if (cl == &dev->iamthif_cl) {
199		rets = mei_amthif_read(dev, file, ubuf, length, offset);
200		goto out;
201	}
202
203	if (cl->read_cb) {
204		cb = cl->read_cb;
205		/* read what left */
206		if (cb->buf_idx > *offset)
207			goto copy_buffer;
208		/* offset is beyond buf_idx we have no more data return 0 */
209		if (cb->buf_idx > 0 && cb->buf_idx <= *offset) {
210			rets = 0;
211			goto free;
212		}
213		/* Offset needs to be cleaned for contiguous reads*/
214		if (cb->buf_idx == 0 && *offset > 0)
215			*offset = 0;
216	} else if (*offset > 0) {
217		*offset = 0;
218	}
219
220	err = mei_cl_read_start(cl, length);
221	if (err && err != -EBUSY) {
222		dev_dbg(&dev->pdev->dev,
223			"mei start read failure with status = %d\n", err);
224		rets = err;
225		goto out;
226	}
227
228	if (MEI_READ_COMPLETE != cl->reading_state &&
229			!waitqueue_active(&cl->rx_wait)) {
230		if (file->f_flags & O_NONBLOCK) {
231			rets = -EAGAIN;
232			goto out;
233		}
234
235		mutex_unlock(&dev->device_lock);
236
237		if (wait_event_interruptible(cl->rx_wait,
238				MEI_READ_COMPLETE == cl->reading_state ||
239				mei_cl_is_transitioning(cl))) {
240
241			if (signal_pending(current))
242				return -EINTR;
243			return -ERESTARTSYS;
244		}
245
246		mutex_lock(&dev->device_lock);
247		if (mei_cl_is_transitioning(cl)) {
248			rets = -EBUSY;
249			goto out;
250		}
251	}
252
253	cb = cl->read_cb;
254
255	if (!cb) {
256		rets = -ENODEV;
257		goto out;
258	}
259	if (cl->reading_state != MEI_READ_COMPLETE) {
260		rets = 0;
261		goto out;
262	}
263	/* now copy the data to user space */
264copy_buffer:
265	dev_dbg(&dev->pdev->dev, "buf.size = %d buf.idx= %ld\n",
266	    cb->response_buffer.size, cb->buf_idx);
267	if (length == 0 || ubuf == NULL || *offset > cb->buf_idx) {
268		rets = -EMSGSIZE;
269		goto free;
270	}
271
272	/* length is being truncated to PAGE_SIZE,
273	 * however buf_idx may point beyond that */
274	length = min_t(size_t, length, cb->buf_idx - *offset);
275
276	if (copy_to_user(ubuf, cb->response_buffer.data + *offset, length)) {
277		dev_dbg(&dev->pdev->dev, "failed to copy data to userland\n");
278		rets = -EFAULT;
279		goto free;
280	}
281
282	rets = length;
283	*offset += length;
284	if ((unsigned long)*offset < cb->buf_idx)
285		goto out;
286
287free:
288	cb_pos = mei_cl_find_read_cb(cl);
289	/* Remove entry from read list */
290	if (cb_pos)
291		list_del(&cb_pos->list);
292	mei_io_cb_free(cb);
293	cl->reading_state = MEI_IDLE;
294	cl->read_cb = NULL;
295out:
296	dev_dbg(&dev->pdev->dev, "end mei read rets= %d\n", rets);
297	mutex_unlock(&dev->device_lock);
298	return rets;
299}
300/**
301 * mei_write - the write function.
302 *
303 * @file: pointer to file structure
304 * @ubuf: pointer to user buffer
305 * @length: buffer length
306 * @offset: data offset in buffer
307 *
308 * returns >=0 data length on success , <0 on error
309 */
310static ssize_t mei_write(struct file *file, const char __user *ubuf,
311			 size_t length, loff_t *offset)
312{
313	struct mei_cl *cl = file->private_data;
314	struct mei_cl_cb *write_cb = NULL;
315	struct mei_device *dev;
316	unsigned long timeout = 0;
317	int rets;
318	int id;
319
320	if (WARN_ON(!cl || !cl->dev))
321		return -ENODEV;
322
323	dev = cl->dev;
324
325	mutex_lock(&dev->device_lock);
326
327	if (dev->dev_state != MEI_DEV_ENABLED) {
328		rets = -ENODEV;
329		goto out;
330	}
331
332	id = mei_me_cl_by_id(dev, cl->me_client_id);
333	if (id < 0) {
334		rets = -ENOTTY;
335		goto out;
336	}
337
338	if (length == 0) {
339		rets = 0;
340		goto out;
341	}
342
343	if (length > dev->me_clients[id].props.max_msg_length) {
344		rets = -EFBIG;
345		goto out;
346	}
347
348	if (cl->state != MEI_FILE_CONNECTED) {
349		dev_err(&dev->pdev->dev, "host client = %d,  is not connected to ME client = %d",
350			cl->host_client_id, cl->me_client_id);
351		rets = -ENODEV;
352		goto out;
353	}
354	if (cl == &dev->iamthif_cl) {
355		write_cb = mei_amthif_find_read_list_entry(dev, file);
356
357		if (write_cb) {
358			timeout = write_cb->read_time +
359				mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
360
361			if (time_after(jiffies, timeout) ||
362			    cl->reading_state == MEI_READ_COMPLETE) {
363				*offset = 0;
364				list_del(&write_cb->list);
365				mei_io_cb_free(write_cb);
366				write_cb = NULL;
367			}
368		}
369	}
370
371	/* free entry used in read */
372	if (cl->reading_state == MEI_READ_COMPLETE) {
373		*offset = 0;
374		write_cb = mei_cl_find_read_cb(cl);
375		if (write_cb) {
376			list_del(&write_cb->list);
377			mei_io_cb_free(write_cb);
378			write_cb = NULL;
379			cl->reading_state = MEI_IDLE;
380			cl->read_cb = NULL;
381		}
382	} else if (cl->reading_state == MEI_IDLE)
383		*offset = 0;
384
385
386	write_cb = mei_io_cb_init(cl, file);
387	if (!write_cb) {
388		dev_err(&dev->pdev->dev, "write cb allocation failed\n");
389		rets = -ENOMEM;
390		goto out;
391	}
392	rets = mei_io_cb_alloc_req_buf(write_cb, length);
393	if (rets)
394		goto out;
395
396	rets = copy_from_user(write_cb->request_buffer.data, ubuf, length);
397	if (rets) {
398		dev_dbg(&dev->pdev->dev, "failed to copy data from userland\n");
399		rets = -EFAULT;
400		goto out;
401	}
402
403	if (cl == &dev->iamthif_cl) {
404		rets = mei_amthif_write(dev, write_cb);
405
406		if (rets) {
407			dev_err(&dev->pdev->dev,
408				"amthif write failed with status = %d\n", rets);
409			goto out;
410		}
411		mutex_unlock(&dev->device_lock);
412		return length;
413	}
414
415	rets = mei_cl_write(cl, write_cb, false);
416out:
417	mutex_unlock(&dev->device_lock);
418	if (rets < 0)
419		mei_io_cb_free(write_cb);
420	return rets;
421}
422
423/**
424 * mei_ioctl_connect_client - the connect to fw client IOCTL function
425 *
426 * @dev: the device structure
427 * @data: IOCTL connect data, input and output parameters
428 * @file: private data of the file object
429 *
430 * Locking: called under "dev->device_lock" lock
431 *
432 * returns 0 on success, <0 on failure.
433 */
434static int mei_ioctl_connect_client(struct file *file,
435			struct mei_connect_client_data *data)
436{
437	struct mei_device *dev;
438	struct mei_client *client;
439	struct mei_cl *cl;
440	int i;
441	int rets;
442
443	cl = file->private_data;
444	if (WARN_ON(!cl || !cl->dev))
445		return -ENODEV;
446
447	dev = cl->dev;
448
449	if (dev->dev_state != MEI_DEV_ENABLED) {
450		rets = -ENODEV;
451		goto end;
452	}
453
454	if (cl->state != MEI_FILE_INITIALIZING &&
455	    cl->state != MEI_FILE_DISCONNECTED) {
456		rets = -EBUSY;
457		goto end;
458	}
459
460	/* find ME client we're trying to connect to */
461	i = mei_me_cl_by_uuid(dev, &data->in_client_uuid);
462	if (i < 0 || dev->me_clients[i].props.fixed_address) {
463		dev_dbg(&dev->pdev->dev, "Cannot connect to FW Client UUID = %pUl\n",
464				&data->in_client_uuid);
465		rets = -ENOTTY;
466		goto end;
467	}
468
469	cl->me_client_id = dev->me_clients[i].client_id;
470	cl->state = MEI_FILE_CONNECTING;
471
472	dev_dbg(&dev->pdev->dev, "Connect to FW Client ID = %d\n",
473			cl->me_client_id);
474	dev_dbg(&dev->pdev->dev, "FW Client - Protocol Version = %d\n",
475			dev->me_clients[i].props.protocol_version);
476	dev_dbg(&dev->pdev->dev, "FW Client - Max Msg Len = %d\n",
477			dev->me_clients[i].props.max_msg_length);
478
479	/* if we're connecting to amthif client then we will use the
480	 * existing connection
481	 */
482	if (uuid_le_cmp(data->in_client_uuid, mei_amthif_guid) == 0) {
483		dev_dbg(&dev->pdev->dev, "FW Client is amthi\n");
484		if (dev->iamthif_cl.state != MEI_FILE_CONNECTED) {
485			rets = -ENODEV;
486			goto end;
487		}
488		mei_cl_unlink(cl);
489
490		kfree(cl);
491		cl = NULL;
492		dev->iamthif_open_count++;
493		file->private_data = &dev->iamthif_cl;
494
495		client = &data->out_client_properties;
496		client->max_msg_length =
497			dev->me_clients[i].props.max_msg_length;
498		client->protocol_version =
499			dev->me_clients[i].props.protocol_version;
500		rets = dev->iamthif_cl.status;
501
502		goto end;
503	}
504
505
506	/* prepare the output buffer */
507	client = &data->out_client_properties;
508	client->max_msg_length = dev->me_clients[i].props.max_msg_length;
509	client->protocol_version = dev->me_clients[i].props.protocol_version;
510	dev_dbg(&dev->pdev->dev, "Can connect?\n");
511
512
513	rets = mei_cl_connect(cl, file);
514
515end:
516	return rets;
517}
518
519
520/**
521 * mei_ioctl - the IOCTL function
522 *
523 * @file: pointer to file structure
524 * @cmd: ioctl command
525 * @data: pointer to mei message structure
526 *
527 * returns 0 on success , <0 on error
528 */
529static long mei_ioctl(struct file *file, unsigned int cmd, unsigned long data)
530{
531	struct mei_device *dev;
532	struct mei_cl *cl = file->private_data;
533	struct mei_connect_client_data *connect_data = NULL;
534	int rets;
535
536	if (cmd != IOCTL_MEI_CONNECT_CLIENT)
537		return -EINVAL;
538
539	if (WARN_ON(!cl || !cl->dev))
540		return -ENODEV;
541
542	dev = cl->dev;
543
544	dev_dbg(&dev->pdev->dev, "IOCTL cmd = 0x%x", cmd);
545
546	mutex_lock(&dev->device_lock);
547	if (dev->dev_state != MEI_DEV_ENABLED) {
548		rets = -ENODEV;
549		goto out;
550	}
551
552	dev_dbg(&dev->pdev->dev, ": IOCTL_MEI_CONNECT_CLIENT.\n");
553
554	connect_data = kzalloc(sizeof(struct mei_connect_client_data),
555							GFP_KERNEL);
556	if (!connect_data) {
557		rets = -ENOMEM;
558		goto out;
559	}
560	dev_dbg(&dev->pdev->dev, "copy connect data from user\n");
561	if (copy_from_user(connect_data, (char __user *)data,
562				sizeof(struct mei_connect_client_data))) {
563		dev_dbg(&dev->pdev->dev, "failed to copy data from userland\n");
564		rets = -EFAULT;
565		goto out;
566	}
567
568	rets = mei_ioctl_connect_client(file, connect_data);
569
570	/* if all is ok, copying the data back to user. */
571	if (rets)
572		goto out;
573
574	dev_dbg(&dev->pdev->dev, "copy connect data to user\n");
575	if (copy_to_user((char __user *)data, connect_data,
576				sizeof(struct mei_connect_client_data))) {
577		dev_dbg(&dev->pdev->dev, "failed to copy data to userland\n");
578		rets = -EFAULT;
579		goto out;
580	}
581
582out:
583	kfree(connect_data);
584	mutex_unlock(&dev->device_lock);
585	return rets;
586}
587
588/**
589 * mei_compat_ioctl - the compat IOCTL function
590 *
591 * @file: pointer to file structure
592 * @cmd: ioctl command
593 * @data: pointer to mei message structure
594 *
595 * returns 0 on success , <0 on error
596 */
597#ifdef CONFIG_COMPAT
598static long mei_compat_ioctl(struct file *file,
599			unsigned int cmd, unsigned long data)
600{
601	return mei_ioctl(file, cmd, (unsigned long)compat_ptr(data));
602}
603#endif
604
605
606/**
607 * mei_poll - the poll function
608 *
609 * @file: pointer to file structure
610 * @wait: pointer to poll_table structure
611 *
612 * returns poll mask
613 */
614static unsigned int mei_poll(struct file *file, poll_table *wait)
615{
616	struct mei_cl *cl = file->private_data;
617	struct mei_device *dev;
618	unsigned int mask = 0;
619
620	if (WARN_ON(!cl || !cl->dev))
621		return POLLERR;
622
623	dev = cl->dev;
624
625	mutex_lock(&dev->device_lock);
626
627	if (!mei_cl_is_connected(cl)) {
628		mask = POLLERR;
629		goto out;
630	}
631
632	mutex_unlock(&dev->device_lock);
633
634
635	if (cl == &dev->iamthif_cl)
636		return mei_amthif_poll(dev, file, wait);
637
638	poll_wait(file, &cl->tx_wait, wait);
639
640	mutex_lock(&dev->device_lock);
641
642	if (!mei_cl_is_connected(cl)) {
643		mask = POLLERR;
644		goto out;
645	}
646
647	mask |= (POLLIN | POLLRDNORM);
648
649out:
650	mutex_unlock(&dev->device_lock);
651	return mask;
652}
653
654/*
655 * file operations structure will be used for mei char device.
656 */
657static const struct file_operations mei_fops = {
658	.owner = THIS_MODULE,
659	.read = mei_read,
660	.unlocked_ioctl = mei_ioctl,
661#ifdef CONFIG_COMPAT
662	.compat_ioctl = mei_compat_ioctl,
663#endif
664	.open = mei_open,
665	.release = mei_release,
666	.write = mei_write,
667	.poll = mei_poll,
668	.llseek = no_llseek
669};
670
671/*
672 * Misc Device Struct
673 */
674static struct miscdevice  mei_misc_device = {
675		.name = "mei",
676		.fops = &mei_fops,
677		.minor = MISC_DYNAMIC_MINOR,
678};
679
680
681int mei_register(struct mei_device *dev)
682{
683	int ret;
684	mei_misc_device.parent = &dev->pdev->dev;
685	ret = misc_register(&mei_misc_device);
686	if (ret)
687		return ret;
688
689	if (mei_dbgfs_register(dev, mei_misc_device.name))
690		dev_err(&dev->pdev->dev, "cannot register debugfs\n");
691
692	return 0;
693}
694EXPORT_SYMBOL_GPL(mei_register);
695
696void mei_deregister(struct mei_device *dev)
697{
698	mei_dbgfs_deregister(dev);
699	misc_deregister(&mei_misc_device);
700	mei_misc_device.parent = NULL;
701}
702EXPORT_SYMBOL_GPL(mei_deregister);
703
704static int __init mei_init(void)
705{
706	return mei_cl_bus_init();
707}
708
709static void __exit mei_exit(void)
710{
711	mei_cl_bus_exit();
712}
713
714module_init(mei_init);
715module_exit(mei_exit);
716
717MODULE_AUTHOR("Intel Corporation");
718MODULE_DESCRIPTION("Intel(R) Management Engine Interface");
719MODULE_LICENSE("GPL v2");
720