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