1/*
2 * Copyright (c) 2012 Intel Corporation. All rights reserved.
3 * Copyright (c) 2006 - 2012 QLogic Corporation. All rights reserved.
4 * Copyright (c) 2006 PathScale, Inc. All rights reserved.
5 *
6 * This software is available to you under a choice of one of two
7 * licenses.  You may choose to be licensed under the terms of the GNU
8 * General Public License (GPL) Version 2, available from the file
9 * COPYING in the main directory of this source tree, or the
10 * OpenIB.org BSD license below:
11 *
12 *     Redistribution and use in source and binary forms, with or
13 *     without modification, are permitted provided that the following
14 *     conditions are met:
15 *
16 *      - Redistributions of source code must retain the above
17 *        copyright notice, this list of conditions and the following
18 *        disclaimer.
19 *
20 *      - Redistributions in binary form must reproduce the above
21 *        copyright notice, this list of conditions and the following
22 *        disclaimer in the documentation and/or other materials
23 *        provided with the distribution.
24 *
25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32 * SOFTWARE.
33 */
34
35#include <linux/module.h>
36#include <linux/fs.h>
37#include <linux/mount.h>
38#include <linux/pagemap.h>
39#include <linux/init.h>
40#include <linux/namei.h>
41
42#include "qib.h"
43
44#define QIBFS_MAGIC 0x726a77
45
46static struct super_block *qib_super;
47
48#define private2dd(file) (file_inode(file)->i_private)
49
50static int qibfs_mknod(struct inode *dir, struct dentry *dentry,
51		       umode_t mode, const struct file_operations *fops,
52		       void *data)
53{
54	int error;
55	struct inode *inode = new_inode(dir->i_sb);
56
57	if (!inode) {
58		error = -EPERM;
59		goto bail;
60	}
61
62	inode->i_ino = get_next_ino();
63	inode->i_mode = mode;
64	inode->i_uid = GLOBAL_ROOT_UID;
65	inode->i_gid = GLOBAL_ROOT_GID;
66	inode->i_blocks = 0;
67	inode->i_atime = CURRENT_TIME;
68	inode->i_mtime = inode->i_atime;
69	inode->i_ctime = inode->i_atime;
70	inode->i_private = data;
71	if (S_ISDIR(mode)) {
72		inode->i_op = &simple_dir_inode_operations;
73		inc_nlink(inode);
74		inc_nlink(dir);
75	}
76
77	inode->i_fop = fops;
78
79	d_instantiate(dentry, inode);
80	error = 0;
81
82bail:
83	return error;
84}
85
86static int create_file(const char *name, umode_t mode,
87		       struct dentry *parent, struct dentry **dentry,
88		       const struct file_operations *fops, void *data)
89{
90	int error;
91
92	mutex_lock(&parent->d_inode->i_mutex);
93	*dentry = lookup_one_len(name, parent, strlen(name));
94	if (!IS_ERR(*dentry))
95		error = qibfs_mknod(parent->d_inode, *dentry,
96				    mode, fops, data);
97	else
98		error = PTR_ERR(*dentry);
99	mutex_unlock(&parent->d_inode->i_mutex);
100
101	return error;
102}
103
104static ssize_t driver_stats_read(struct file *file, char __user *buf,
105				 size_t count, loff_t *ppos)
106{
107	qib_stats.sps_ints = qib_sps_ints();
108	return simple_read_from_buffer(buf, count, ppos, &qib_stats,
109				       sizeof qib_stats);
110}
111
112/*
113 * driver stats field names, one line per stat, single string.  Used by
114 * programs like ipathstats to print the stats in a way which works for
115 * different versions of drivers, without changing program source.
116 * if qlogic_ib_stats changes, this needs to change.  Names need to be
117 * 12 chars or less (w/o newline), for proper display by ipathstats utility.
118 */
119static const char qib_statnames[] =
120	"KernIntr\n"
121	"ErrorIntr\n"
122	"Tx_Errs\n"
123	"Rcv_Errs\n"
124	"H/W_Errs\n"
125	"NoPIOBufs\n"
126	"CtxtsOpen\n"
127	"RcvLen_Errs\n"
128	"EgrBufFull\n"
129	"EgrHdrFull\n"
130	;
131
132static ssize_t driver_names_read(struct file *file, char __user *buf,
133				 size_t count, loff_t *ppos)
134{
135	return simple_read_from_buffer(buf, count, ppos, qib_statnames,
136		sizeof qib_statnames - 1); /* no null */
137}
138
139static const struct file_operations driver_ops[] = {
140	{ .read = driver_stats_read, .llseek = generic_file_llseek, },
141	{ .read = driver_names_read, .llseek = generic_file_llseek, },
142};
143
144/* read the per-device counters */
145static ssize_t dev_counters_read(struct file *file, char __user *buf,
146				 size_t count, loff_t *ppos)
147{
148	u64 *counters;
149	size_t avail;
150	struct qib_devdata *dd = private2dd(file);
151
152	avail = dd->f_read_cntrs(dd, *ppos, NULL, &counters);
153	return simple_read_from_buffer(buf, count, ppos, counters, avail);
154}
155
156/* read the per-device counters */
157static ssize_t dev_names_read(struct file *file, char __user *buf,
158			      size_t count, loff_t *ppos)
159{
160	char *names;
161	size_t avail;
162	struct qib_devdata *dd = private2dd(file);
163
164	avail = dd->f_read_cntrs(dd, *ppos, &names, NULL);
165	return simple_read_from_buffer(buf, count, ppos, names, avail);
166}
167
168static const struct file_operations cntr_ops[] = {
169	{ .read = dev_counters_read, .llseek = generic_file_llseek, },
170	{ .read = dev_names_read, .llseek = generic_file_llseek, },
171};
172
173/*
174 * Could use file_inode(file)->i_ino to figure out which file,
175 * instead of separate routine for each, but for now, this works...
176 */
177
178/* read the per-port names (same for each port) */
179static ssize_t portnames_read(struct file *file, char __user *buf,
180			      size_t count, loff_t *ppos)
181{
182	char *names;
183	size_t avail;
184	struct qib_devdata *dd = private2dd(file);
185
186	avail = dd->f_read_portcntrs(dd, *ppos, 0, &names, NULL);
187	return simple_read_from_buffer(buf, count, ppos, names, avail);
188}
189
190/* read the per-port counters for port 1 (pidx 0) */
191static ssize_t portcntrs_1_read(struct file *file, char __user *buf,
192				size_t count, loff_t *ppos)
193{
194	u64 *counters;
195	size_t avail;
196	struct qib_devdata *dd = private2dd(file);
197
198	avail = dd->f_read_portcntrs(dd, *ppos, 0, NULL, &counters);
199	return simple_read_from_buffer(buf, count, ppos, counters, avail);
200}
201
202/* read the per-port counters for port 2 (pidx 1) */
203static ssize_t portcntrs_2_read(struct file *file, char __user *buf,
204				size_t count, loff_t *ppos)
205{
206	u64 *counters;
207	size_t avail;
208	struct qib_devdata *dd = private2dd(file);
209
210	avail = dd->f_read_portcntrs(dd, *ppos, 1, NULL, &counters);
211	return simple_read_from_buffer(buf, count, ppos, counters, avail);
212}
213
214static const struct file_operations portcntr_ops[] = {
215	{ .read = portnames_read, .llseek = generic_file_llseek, },
216	{ .read = portcntrs_1_read, .llseek = generic_file_llseek, },
217	{ .read = portcntrs_2_read, .llseek = generic_file_llseek, },
218};
219
220/*
221 * read the per-port QSFP data for port 1 (pidx 0)
222 */
223static ssize_t qsfp_1_read(struct file *file, char __user *buf,
224			   size_t count, loff_t *ppos)
225{
226	struct qib_devdata *dd = private2dd(file);
227	char *tmp;
228	int ret;
229
230	tmp = kmalloc(PAGE_SIZE, GFP_KERNEL);
231	if (!tmp)
232		return -ENOMEM;
233
234	ret = qib_qsfp_dump(dd->pport, tmp, PAGE_SIZE);
235	if (ret > 0)
236		ret = simple_read_from_buffer(buf, count, ppos, tmp, ret);
237	kfree(tmp);
238	return ret;
239}
240
241/*
242 * read the per-port QSFP data for port 2 (pidx 1)
243 */
244static ssize_t qsfp_2_read(struct file *file, char __user *buf,
245			   size_t count, loff_t *ppos)
246{
247	struct qib_devdata *dd = private2dd(file);
248	char *tmp;
249	int ret;
250
251	if (dd->num_pports < 2)
252		return -ENODEV;
253
254	tmp = kmalloc(PAGE_SIZE, GFP_KERNEL);
255	if (!tmp)
256		return -ENOMEM;
257
258	ret = qib_qsfp_dump(dd->pport + 1, tmp, PAGE_SIZE);
259	if (ret > 0)
260		ret = simple_read_from_buffer(buf, count, ppos, tmp, ret);
261	kfree(tmp);
262	return ret;
263}
264
265static const struct file_operations qsfp_ops[] = {
266	{ .read = qsfp_1_read, .llseek = generic_file_llseek, },
267	{ .read = qsfp_2_read, .llseek = generic_file_llseek, },
268};
269
270static ssize_t flash_read(struct file *file, char __user *buf,
271			  size_t count, loff_t *ppos)
272{
273	struct qib_devdata *dd;
274	ssize_t ret;
275	loff_t pos;
276	char *tmp;
277
278	pos = *ppos;
279
280	if (pos < 0) {
281		ret = -EINVAL;
282		goto bail;
283	}
284
285	if (pos >= sizeof(struct qib_flash)) {
286		ret = 0;
287		goto bail;
288	}
289
290	if (count > sizeof(struct qib_flash) - pos)
291		count = sizeof(struct qib_flash) - pos;
292
293	tmp = kmalloc(count, GFP_KERNEL);
294	if (!tmp) {
295		ret = -ENOMEM;
296		goto bail;
297	}
298
299	dd = private2dd(file);
300	if (qib_eeprom_read(dd, pos, tmp, count)) {
301		qib_dev_err(dd, "failed to read from flash\n");
302		ret = -ENXIO;
303		goto bail_tmp;
304	}
305
306	if (copy_to_user(buf, tmp, count)) {
307		ret = -EFAULT;
308		goto bail_tmp;
309	}
310
311	*ppos = pos + count;
312	ret = count;
313
314bail_tmp:
315	kfree(tmp);
316
317bail:
318	return ret;
319}
320
321static ssize_t flash_write(struct file *file, const char __user *buf,
322			   size_t count, loff_t *ppos)
323{
324	struct qib_devdata *dd;
325	ssize_t ret;
326	loff_t pos;
327	char *tmp;
328
329	pos = *ppos;
330
331	if (pos != 0) {
332		ret = -EINVAL;
333		goto bail;
334	}
335
336	if (count != sizeof(struct qib_flash)) {
337		ret = -EINVAL;
338		goto bail;
339	}
340
341	tmp = kmalloc(count, GFP_KERNEL);
342	if (!tmp) {
343		ret = -ENOMEM;
344		goto bail;
345	}
346
347	if (copy_from_user(tmp, buf, count)) {
348		ret = -EFAULT;
349		goto bail_tmp;
350	}
351
352	dd = private2dd(file);
353	if (qib_eeprom_write(dd, pos, tmp, count)) {
354		ret = -ENXIO;
355		qib_dev_err(dd, "failed to write to flash\n");
356		goto bail_tmp;
357	}
358
359	*ppos = pos + count;
360	ret = count;
361
362bail_tmp:
363	kfree(tmp);
364
365bail:
366	return ret;
367}
368
369static const struct file_operations flash_ops = {
370	.read = flash_read,
371	.write = flash_write,
372	.llseek = default_llseek,
373};
374
375static int add_cntr_files(struct super_block *sb, struct qib_devdata *dd)
376{
377	struct dentry *dir, *tmp;
378	char unit[10];
379	int ret, i;
380
381	/* create the per-unit directory */
382	snprintf(unit, sizeof unit, "%u", dd->unit);
383	ret = create_file(unit, S_IFDIR|S_IRUGO|S_IXUGO, sb->s_root, &dir,
384			  &simple_dir_operations, dd);
385	if (ret) {
386		pr_err("create_file(%s) failed: %d\n", unit, ret);
387		goto bail;
388	}
389
390	/* create the files in the new directory */
391	ret = create_file("counters", S_IFREG|S_IRUGO, dir, &tmp,
392			  &cntr_ops[0], dd);
393	if (ret) {
394		pr_err("create_file(%s/counters) failed: %d\n",
395		       unit, ret);
396		goto bail;
397	}
398	ret = create_file("counter_names", S_IFREG|S_IRUGO, dir, &tmp,
399			  &cntr_ops[1], dd);
400	if (ret) {
401		pr_err("create_file(%s/counter_names) failed: %d\n",
402		       unit, ret);
403		goto bail;
404	}
405	ret = create_file("portcounter_names", S_IFREG|S_IRUGO, dir, &tmp,
406			  &portcntr_ops[0], dd);
407	if (ret) {
408		pr_err("create_file(%s/%s) failed: %d\n",
409		       unit, "portcounter_names", ret);
410		goto bail;
411	}
412	for (i = 1; i <= dd->num_pports; i++) {
413		char fname[24];
414
415		sprintf(fname, "port%dcounters", i);
416		/* create the files in the new directory */
417		ret = create_file(fname, S_IFREG|S_IRUGO, dir, &tmp,
418				  &portcntr_ops[i], dd);
419		if (ret) {
420			pr_err("create_file(%s/%s) failed: %d\n",
421				unit, fname, ret);
422			goto bail;
423		}
424		if (!(dd->flags & QIB_HAS_QSFP))
425			continue;
426		sprintf(fname, "qsfp%d", i);
427		ret = create_file(fname, S_IFREG|S_IRUGO, dir, &tmp,
428				  &qsfp_ops[i - 1], dd);
429		if (ret) {
430			pr_err("create_file(%s/%s) failed: %d\n",
431				unit, fname, ret);
432			goto bail;
433		}
434	}
435
436	ret = create_file("flash", S_IFREG|S_IWUSR|S_IRUGO, dir, &tmp,
437			  &flash_ops, dd);
438	if (ret)
439		pr_err("create_file(%s/flash) failed: %d\n",
440			unit, ret);
441bail:
442	return ret;
443}
444
445static int remove_file(struct dentry *parent, char *name)
446{
447	struct dentry *tmp;
448	int ret;
449
450	tmp = lookup_one_len(name, parent, strlen(name));
451
452	if (IS_ERR(tmp)) {
453		ret = PTR_ERR(tmp);
454		goto bail;
455	}
456
457	spin_lock(&tmp->d_lock);
458	if (!(d_unhashed(tmp) && tmp->d_inode)) {
459		__d_drop(tmp);
460		spin_unlock(&tmp->d_lock);
461		simple_unlink(parent->d_inode, tmp);
462	} else {
463		spin_unlock(&tmp->d_lock);
464	}
465	dput(tmp);
466
467	ret = 0;
468bail:
469	/*
470	 * We don't expect clients to care about the return value, but
471	 * it's there if they need it.
472	 */
473	return ret;
474}
475
476static int remove_device_files(struct super_block *sb,
477			       struct qib_devdata *dd)
478{
479	struct dentry *dir, *root;
480	char unit[10];
481	int ret, i;
482
483	root = dget(sb->s_root);
484	mutex_lock(&root->d_inode->i_mutex);
485	snprintf(unit, sizeof unit, "%u", dd->unit);
486	dir = lookup_one_len(unit, root, strlen(unit));
487
488	if (IS_ERR(dir)) {
489		ret = PTR_ERR(dir);
490		pr_err("Lookup of %s failed\n", unit);
491		goto bail;
492	}
493
494	mutex_lock(&dir->d_inode->i_mutex);
495	remove_file(dir, "counters");
496	remove_file(dir, "counter_names");
497	remove_file(dir, "portcounter_names");
498	for (i = 0; i < dd->num_pports; i++) {
499		char fname[24];
500
501		sprintf(fname, "port%dcounters", i + 1);
502		remove_file(dir, fname);
503		if (dd->flags & QIB_HAS_QSFP) {
504			sprintf(fname, "qsfp%d", i + 1);
505			remove_file(dir, fname);
506		}
507	}
508	remove_file(dir, "flash");
509	mutex_unlock(&dir->d_inode->i_mutex);
510	ret = simple_rmdir(root->d_inode, dir);
511	d_delete(dir);
512	dput(dir);
513
514bail:
515	mutex_unlock(&root->d_inode->i_mutex);
516	dput(root);
517	return ret;
518}
519
520/*
521 * This fills everything in when the fs is mounted, to handle umount/mount
522 * after device init.  The direct add_cntr_files() call handles adding
523 * them from the init code, when the fs is already mounted.
524 */
525static int qibfs_fill_super(struct super_block *sb, void *data, int silent)
526{
527	struct qib_devdata *dd, *tmp;
528	unsigned long flags;
529	int ret;
530
531	static struct tree_descr files[] = {
532		[2] = {"driver_stats", &driver_ops[0], S_IRUGO},
533		[3] = {"driver_stats_names", &driver_ops[1], S_IRUGO},
534		{""},
535	};
536
537	ret = simple_fill_super(sb, QIBFS_MAGIC, files);
538	if (ret) {
539		pr_err("simple_fill_super failed: %d\n", ret);
540		goto bail;
541	}
542
543	spin_lock_irqsave(&qib_devs_lock, flags);
544
545	list_for_each_entry_safe(dd, tmp, &qib_dev_list, list) {
546		spin_unlock_irqrestore(&qib_devs_lock, flags);
547		ret = add_cntr_files(sb, dd);
548		if (ret)
549			goto bail;
550		spin_lock_irqsave(&qib_devs_lock, flags);
551	}
552
553	spin_unlock_irqrestore(&qib_devs_lock, flags);
554
555bail:
556	return ret;
557}
558
559static struct dentry *qibfs_mount(struct file_system_type *fs_type, int flags,
560			const char *dev_name, void *data)
561{
562	struct dentry *ret;
563	ret = mount_single(fs_type, flags, data, qibfs_fill_super);
564	if (!IS_ERR(ret))
565		qib_super = ret->d_sb;
566	return ret;
567}
568
569static void qibfs_kill_super(struct super_block *s)
570{
571	kill_litter_super(s);
572	qib_super = NULL;
573}
574
575int qibfs_add(struct qib_devdata *dd)
576{
577	int ret;
578
579	/*
580	 * On first unit initialized, qib_super will not yet exist
581	 * because nobody has yet tried to mount the filesystem, so
582	 * we can't consider that to be an error; if an error occurs
583	 * during the mount, that will get a complaint, so this is OK.
584	 * add_cntr_files() for all units is done at mount from
585	 * qibfs_fill_super(), so one way or another, everything works.
586	 */
587	if (qib_super == NULL)
588		ret = 0;
589	else
590		ret = add_cntr_files(qib_super, dd);
591	return ret;
592}
593
594int qibfs_remove(struct qib_devdata *dd)
595{
596	int ret = 0;
597
598	if (qib_super)
599		ret = remove_device_files(qib_super, dd);
600
601	return ret;
602}
603
604static struct file_system_type qibfs_fs_type = {
605	.owner =        THIS_MODULE,
606	.name =         "ipathfs",
607	.mount =        qibfs_mount,
608	.kill_sb =      qibfs_kill_super,
609};
610MODULE_ALIAS_FS("ipathfs");
611
612int __init qib_init_qibfs(void)
613{
614	return register_filesystem(&qibfs_fs_type);
615}
616
617int __exit qib_exit_qibfs(void)
618{
619	return unregister_filesystem(&qibfs_fs_type);
620}
621