xref: /openbmc/linux/drivers/scsi/fnic/fnic_debugfs.c (revision 8a26af30)
1 /*
2  * Copyright 2012 Cisco Systems, Inc.  All rights reserved.
3  *
4  * This program is free software; you may redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; version 2 of the License.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
9  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
10  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
11  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
12  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
13  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
14  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
15  * SOFTWARE.
16  */
17 
18 #include <linux/module.h>
19 #include <linux/errno.h>
20 #include <linux/debugfs.h>
21 #include "fnic.h"
22 
23 static struct dentry *fnic_trace_debugfs_root;
24 static struct dentry *fnic_trace_debugfs_file;
25 static struct dentry *fnic_trace_enable;
26 static struct dentry *fnic_stats_debugfs_root;
27 
28 static struct dentry *fnic_fc_trace_debugfs_file;
29 static struct dentry *fnic_fc_rdata_trace_debugfs_file;
30 static struct dentry *fnic_fc_trace_enable;
31 static struct dentry *fnic_fc_trace_clear;
32 
33 struct fc_trace_flag_type {
34 	u8 fc_row_file;
35 	u8 fc_normal_file;
36 	u8 fnic_trace;
37 	u8 fc_trace;
38 	u8 fc_clear;
39 };
40 
41 static struct fc_trace_flag_type *fc_trc_flag;
42 
43 /*
44  * fnic_debugfs_init - Initialize debugfs for fnic debug logging
45  *
46  * Description:
47  * When Debugfs is configured this routine sets up the fnic debugfs
48  * file system. If not already created, this routine will create the
49  * fnic directory and statistics directory for trace buffer and
50  * stats logging.
51  */
52 int fnic_debugfs_init(void)
53 {
54 	int rc = -1;
55 	fnic_trace_debugfs_root = debugfs_create_dir("fnic", NULL);
56 	if (!fnic_trace_debugfs_root) {
57 		printk(KERN_DEBUG "Cannot create debugfs root\n");
58 		return rc;
59 	}
60 
61 	if (!fnic_trace_debugfs_root) {
62 		printk(KERN_DEBUG
63 			"fnic root directory doesn't exist in debugfs\n");
64 		return rc;
65 	}
66 
67 	fnic_stats_debugfs_root = debugfs_create_dir("statistics",
68 						fnic_trace_debugfs_root);
69 	if (!fnic_stats_debugfs_root) {
70 		printk(KERN_DEBUG "Cannot create Statistics directory\n");
71 		return rc;
72 	}
73 
74 	/* Allocate memory to structure */
75 	fc_trc_flag = (struct fc_trace_flag_type *)
76 		vmalloc(sizeof(struct fc_trace_flag_type));
77 
78 	if (fc_trc_flag) {
79 		fc_trc_flag->fc_row_file = 0;
80 		fc_trc_flag->fc_normal_file = 1;
81 		fc_trc_flag->fnic_trace = 2;
82 		fc_trc_flag->fc_trace = 3;
83 		fc_trc_flag->fc_clear = 4;
84 	}
85 
86 	rc = 0;
87 	return rc;
88 }
89 
90 /*
91  * fnic_debugfs_terminate - Tear down debugfs infrastructure
92  *
93  * Description:
94  * When Debugfs is configured this routine removes debugfs file system
95  * elements that are specific to fnic.
96  */
97 void fnic_debugfs_terminate(void)
98 {
99 	debugfs_remove(fnic_stats_debugfs_root);
100 	fnic_stats_debugfs_root = NULL;
101 
102 	debugfs_remove(fnic_trace_debugfs_root);
103 	fnic_trace_debugfs_root = NULL;
104 
105 	if (fc_trc_flag)
106 		vfree(fc_trc_flag);
107 }
108 
109 /*
110  * fnic_trace_ctrl_open - Open the trace_enable file for fnic_trace
111  *               Or Open fc_trace_enable file for fc_trace
112  * @inode: The inode pointer.
113  * @file: The file pointer to attach the trace enable/disable flag.
114  *
115  * Description:
116  * This routine opens a debugsfs file trace_enable or fc_trace_enable.
117  *
118  * Returns:
119  * This function returns zero if successful.
120  */
121 static int fnic_trace_ctrl_open(struct inode *inode, struct file *filp)
122 {
123 	filp->private_data = inode->i_private;
124 	return 0;
125 }
126 
127 /*
128  * fnic_trace_ctrl_read -
129  *          Read  trace_enable ,fc_trace_enable
130  *              or fc_trace_clear debugfs file
131  * @filp: The file pointer to read from.
132  * @ubuf: The buffer to copy the data to.
133  * @cnt: The number of bytes to read.
134  * @ppos: The position in the file to start reading from.
135  *
136  * Description:
137  * This routine reads value of variable fnic_tracing_enabled or
138  * fnic_fc_tracing_enabled or fnic_fc_trace_cleared
139  * and stores into local @buf.
140  * It will start reading file at @ppos and
141  * copy up to @cnt of data to @ubuf from @buf.
142  *
143  * Returns:
144  * This function returns the amount of data that was read.
145  */
146 static ssize_t fnic_trace_ctrl_read(struct file *filp,
147 				  char __user *ubuf,
148 				  size_t cnt, loff_t *ppos)
149 {
150 	char buf[64];
151 	int len;
152 	u8 *trace_type;
153 	len = 0;
154 	trace_type = (u8 *)filp->private_data;
155 	if (*trace_type == fc_trc_flag->fnic_trace)
156 		len = sprintf(buf, "%u\n", fnic_tracing_enabled);
157 	else if (*trace_type == fc_trc_flag->fc_trace)
158 		len = sprintf(buf, "%u\n", fnic_fc_tracing_enabled);
159 	else if (*trace_type == fc_trc_flag->fc_clear)
160 		len = sprintf(buf, "%u\n", fnic_fc_trace_cleared);
161 	else
162 		pr_err("fnic: Cannot read to any debugfs file\n");
163 
164 	return simple_read_from_buffer(ubuf, cnt, ppos, buf, len);
165 }
166 
167 /*
168  * fnic_trace_ctrl_write -
169  * Write to trace_enable, fc_trace_enable or
170  *         fc_trace_clear debugfs file
171  * @filp: The file pointer to write from.
172  * @ubuf: The buffer to copy the data from.
173  * @cnt: The number of bytes to write.
174  * @ppos: The position in the file to start writing to.
175  *
176  * Description:
177  * This routine writes data from user buffer @ubuf to buffer @buf and
178  * sets fc_trace_enable ,tracing_enable or fnic_fc_trace_cleared
179  * value as per user input.
180  *
181  * Returns:
182  * This function returns the amount of data that was written.
183  */
184 static ssize_t fnic_trace_ctrl_write(struct file *filp,
185 				  const char __user *ubuf,
186 				  size_t cnt, loff_t *ppos)
187 {
188 	char buf[64];
189 	unsigned long val;
190 	int ret;
191 	u8 *trace_type;
192 	trace_type = (u8 *)filp->private_data;
193 
194 	if (cnt >= sizeof(buf))
195 		return -EINVAL;
196 
197 	if (copy_from_user(&buf, ubuf, cnt))
198 		return -EFAULT;
199 
200 	buf[cnt] = 0;
201 
202 	ret = kstrtoul(buf, 10, &val);
203 	if (ret < 0)
204 		return ret;
205 
206 	if (*trace_type == fc_trc_flag->fnic_trace)
207 		fnic_tracing_enabled = val;
208 	else if (*trace_type == fc_trc_flag->fc_trace)
209 		fnic_fc_tracing_enabled = val;
210 	else if (*trace_type == fc_trc_flag->fc_clear)
211 		fnic_fc_trace_cleared = val;
212 	else
213 		pr_err("fnic: cannot write to any debufs file\n");
214 
215 	(*ppos)++;
216 
217 	return cnt;
218 }
219 
220 static const struct file_operations fnic_trace_ctrl_fops = {
221 	.owner = THIS_MODULE,
222 	.open = fnic_trace_ctrl_open,
223 	.read = fnic_trace_ctrl_read,
224 	.write = fnic_trace_ctrl_write,
225 };
226 
227 /*
228  * fnic_trace_debugfs_open - Open the fnic trace log
229  * @inode: The inode pointer
230  * @file: The file pointer to attach the log output
231  *
232  * Description:
233  * This routine is the entry point for the debugfs open file operation.
234  * It allocates the necessary buffer for the log, fills the buffer from
235  * the in-memory log and then returns a pointer to that log in
236  * the private_data field in @file.
237  *
238  * Returns:
239  * This function returns zero if successful. On error it will return
240  * a negative error value.
241  */
242 static int fnic_trace_debugfs_open(struct inode *inode,
243 				  struct file *file)
244 {
245 	fnic_dbgfs_t *fnic_dbg_prt;
246 	u8 *rdata_ptr;
247 	rdata_ptr = (u8 *)inode->i_private;
248 	fnic_dbg_prt = kzalloc(sizeof(fnic_dbgfs_t), GFP_KERNEL);
249 	if (!fnic_dbg_prt)
250 		return -ENOMEM;
251 
252 	if (*rdata_ptr == fc_trc_flag->fnic_trace) {
253 		fnic_dbg_prt->buffer = vmalloc(3 *
254 					(trace_max_pages * PAGE_SIZE));
255 		if (!fnic_dbg_prt->buffer) {
256 			kfree(fnic_dbg_prt);
257 			return -ENOMEM;
258 		}
259 		memset((void *)fnic_dbg_prt->buffer, 0,
260 		3 * (trace_max_pages * PAGE_SIZE));
261 		fnic_dbg_prt->buffer_len = fnic_get_trace_data(fnic_dbg_prt);
262 	} else {
263 		fnic_dbg_prt->buffer =
264 			vmalloc(3 * (fnic_fc_trace_max_pages * PAGE_SIZE));
265 		if (!fnic_dbg_prt->buffer) {
266 			kfree(fnic_dbg_prt);
267 			return -ENOMEM;
268 		}
269 		memset((void *)fnic_dbg_prt->buffer, 0,
270 			3 * (fnic_fc_trace_max_pages * PAGE_SIZE));
271 		fnic_dbg_prt->buffer_len =
272 			fnic_fc_trace_get_data(fnic_dbg_prt, *rdata_ptr);
273 	}
274 	file->private_data = fnic_dbg_prt;
275 
276 	return 0;
277 }
278 
279 /*
280  * fnic_trace_debugfs_lseek - Seek through a debugfs file
281  * @file: The file pointer to seek through.
282  * @offset: The offset to seek to or the amount to seek by.
283  * @howto: Indicates how to seek.
284  *
285  * Description:
286  * This routine is the entry point for the debugfs lseek file operation.
287  * The @howto parameter indicates whether @offset is the offset to directly
288  * seek to, or if it is a value to seek forward or reverse by. This function
289  * figures out what the new offset of the debugfs file will be and assigns
290  * that value to the f_pos field of @file.
291  *
292  * Returns:
293  * This function returns the new offset if successful and returns a negative
294  * error if unable to process the seek.
295  */
296 static loff_t fnic_trace_debugfs_lseek(struct file *file,
297 					loff_t offset,
298 					int howto)
299 {
300 	fnic_dbgfs_t *fnic_dbg_prt = file->private_data;
301 	return fixed_size_llseek(file, offset, howto,
302 				fnic_dbg_prt->buffer_len);
303 }
304 
305 /*
306  * fnic_trace_debugfs_read - Read a debugfs file
307  * @file: The file pointer to read from.
308  * @ubuf: The buffer to copy the data to.
309  * @nbytes: The number of bytes to read.
310  * @pos: The position in the file to start reading from.
311  *
312  * Description:
313  * This routine reads data from the buffer indicated in the private_data
314  * field of @file. It will start reading at @pos and copy up to @nbytes of
315  * data to @ubuf.
316  *
317  * Returns:
318  * This function returns the amount of data that was read (this could be
319  * less than @nbytes if the end of the file was reached).
320  */
321 static ssize_t fnic_trace_debugfs_read(struct file *file,
322 					char __user *ubuf,
323 					size_t nbytes,
324 					loff_t *pos)
325 {
326 	fnic_dbgfs_t *fnic_dbg_prt = file->private_data;
327 	int rc = 0;
328 	rc = simple_read_from_buffer(ubuf, nbytes, pos,
329 				  fnic_dbg_prt->buffer,
330 				  fnic_dbg_prt->buffer_len);
331 	return rc;
332 }
333 
334 /*
335  * fnic_trace_debugfs_release - Release the buffer used to store
336  * debugfs file data
337  * @inode: The inode pointer
338  * @file: The file pointer that contains the buffer to release
339  *
340  * Description:
341  * This routine frees the buffer that was allocated when the debugfs
342  * file was opened.
343  *
344  * Returns:
345  * This function returns zero.
346  */
347 static int fnic_trace_debugfs_release(struct inode *inode,
348 					  struct file *file)
349 {
350 	fnic_dbgfs_t *fnic_dbg_prt = file->private_data;
351 
352 	vfree(fnic_dbg_prt->buffer);
353 	kfree(fnic_dbg_prt);
354 	return 0;
355 }
356 
357 static const struct file_operations fnic_trace_debugfs_fops = {
358 	.owner = THIS_MODULE,
359 	.open = fnic_trace_debugfs_open,
360 	.llseek = fnic_trace_debugfs_lseek,
361 	.read = fnic_trace_debugfs_read,
362 	.release = fnic_trace_debugfs_release,
363 };
364 
365 /*
366  * fnic_trace_debugfs_init - Initialize debugfs for fnic trace logging
367  *
368  * Description:
369  * When Debugfs is configured this routine sets up the fnic debugfs
370  * file system. If not already created, this routine will create the
371  * create file trace to log fnic trace buffer output into debugfs and
372  * it will also create file trace_enable to control enable/disable of
373  * trace logging into trace buffer.
374  */
375 int fnic_trace_debugfs_init(void)
376 {
377 	int rc = -1;
378 	if (!fnic_trace_debugfs_root) {
379 		printk(KERN_DEBUG
380 			"FNIC Debugfs root directory doesn't exist\n");
381 		return rc;
382 	}
383 	fnic_trace_enable = debugfs_create_file("tracing_enable",
384 					S_IFREG|S_IRUGO|S_IWUSR,
385 					fnic_trace_debugfs_root,
386 					&(fc_trc_flag->fnic_trace),
387 					&fnic_trace_ctrl_fops);
388 
389 	if (!fnic_trace_enable) {
390 		printk(KERN_DEBUG
391 			"Cannot create trace_enable file under debugfs\n");
392 		return rc;
393 	}
394 
395 	fnic_trace_debugfs_file = debugfs_create_file("trace",
396 					S_IFREG|S_IRUGO|S_IWUSR,
397 					fnic_trace_debugfs_root,
398 					&(fc_trc_flag->fnic_trace),
399 					&fnic_trace_debugfs_fops);
400 
401 	if (!fnic_trace_debugfs_file) {
402 		printk(KERN_DEBUG
403 			"Cannot create trace file under debugfs\n");
404 		return rc;
405 	}
406 	rc = 0;
407 	return rc;
408 }
409 
410 /*
411  * fnic_trace_debugfs_terminate - Tear down debugfs infrastructure
412  *
413  * Description:
414  * When Debugfs is configured this routine removes debugfs file system
415  * elements that are specific to fnic trace logging.
416  */
417 void fnic_trace_debugfs_terminate(void)
418 {
419 	debugfs_remove(fnic_trace_debugfs_file);
420 	fnic_trace_debugfs_file = NULL;
421 
422 	debugfs_remove(fnic_trace_enable);
423 	fnic_trace_enable = NULL;
424 }
425 
426 /*
427  * fnic_fc_trace_debugfs_init -
428  * Initialize debugfs for fnic control frame trace logging
429  *
430  * Description:
431  * When Debugfs is configured this routine sets up the fnic_fc debugfs
432  * file system. If not already created, this routine will create the
433  * create file trace to log fnic fc trace buffer output into debugfs and
434  * it will also create file fc_trace_enable to control enable/disable of
435  * trace logging into trace buffer.
436  */
437 
438 int fnic_fc_trace_debugfs_init(void)
439 {
440 	int rc = -1;
441 
442 	if (!fnic_trace_debugfs_root) {
443 		pr_err("fnic:Debugfs root directory doesn't exist\n");
444 		return rc;
445 	}
446 
447 	fnic_fc_trace_enable = debugfs_create_file("fc_trace_enable",
448 					S_IFREG|S_IRUGO|S_IWUSR,
449 					fnic_trace_debugfs_root,
450 					&(fc_trc_flag->fc_trace),
451 					&fnic_trace_ctrl_fops);
452 
453 	if (!fnic_fc_trace_enable) {
454 		pr_err("fnic: Failed create fc_trace_enable file\n");
455 		return rc;
456 	}
457 
458 	fnic_fc_trace_clear = debugfs_create_file("fc_trace_clear",
459 					S_IFREG|S_IRUGO|S_IWUSR,
460 					fnic_trace_debugfs_root,
461 					&(fc_trc_flag->fc_clear),
462 					&fnic_trace_ctrl_fops);
463 
464 	if (!fnic_fc_trace_clear) {
465 		pr_err("fnic: Failed to create fc_trace_enable file\n");
466 		return rc;
467 	}
468 
469 	fnic_fc_rdata_trace_debugfs_file =
470 		debugfs_create_file("fc_trace_rdata",
471 				    S_IFREG|S_IRUGO|S_IWUSR,
472 				    fnic_trace_debugfs_root,
473 				    &(fc_trc_flag->fc_normal_file),
474 				    &fnic_trace_debugfs_fops);
475 
476 	if (!fnic_fc_rdata_trace_debugfs_file) {
477 		pr_err("fnic: Failed create fc_rdata_trace file\n");
478 		return rc;
479 	}
480 
481 	fnic_fc_trace_debugfs_file =
482 		debugfs_create_file("fc_trace",
483 				    S_IFREG|S_IRUGO|S_IWUSR,
484 				    fnic_trace_debugfs_root,
485 				    &(fc_trc_flag->fc_row_file),
486 				    &fnic_trace_debugfs_fops);
487 
488 	if (!fnic_fc_trace_debugfs_file) {
489 		pr_err("fnic: Failed to create fc_trace file\n");
490 		return rc;
491 	}
492 	rc = 0;
493 	return rc;
494 }
495 
496 /*
497  * fnic_fc_trace_debugfs_terminate - Tear down debugfs infrastructure
498  *
499  * Description:
500  * When Debugfs is configured this routine removes debugfs file system
501  * elements that are specific to fnic_fc trace logging.
502  */
503 
504 void fnic_fc_trace_debugfs_terminate(void)
505 {
506 	debugfs_remove(fnic_fc_trace_debugfs_file);
507 	fnic_fc_trace_debugfs_file = NULL;
508 
509 	debugfs_remove(fnic_fc_rdata_trace_debugfs_file);
510 	fnic_fc_rdata_trace_debugfs_file = NULL;
511 
512 	debugfs_remove(fnic_fc_trace_enable);
513 	fnic_fc_trace_enable = NULL;
514 
515 	debugfs_remove(fnic_fc_trace_clear);
516 	fnic_fc_trace_clear = NULL;
517 }
518 
519 /*
520  * fnic_reset_stats_open - Open the reset_stats file
521  * @inode: The inode pointer.
522  * @file: The file pointer to attach the stats reset flag.
523  *
524  * Description:
525  * This routine opens a debugsfs file reset_stats and stores i_private data
526  * to debug structure to retrieve later for while performing other
527  * file oprations.
528  *
529  * Returns:
530  * This function returns zero if successful.
531  */
532 static int fnic_reset_stats_open(struct inode *inode, struct file *file)
533 {
534 	struct stats_debug_info *debug;
535 
536 	debug = kzalloc(sizeof(struct stats_debug_info), GFP_KERNEL);
537 	if (!debug)
538 		return -ENOMEM;
539 
540 	debug->i_private = inode->i_private;
541 
542 	file->private_data = debug;
543 
544 	return 0;
545 }
546 
547 /*
548  * fnic_reset_stats_read - Read a reset_stats debugfs file
549  * @filp: The file pointer to read from.
550  * @ubuf: The buffer to copy the data to.
551  * @cnt: The number of bytes to read.
552  * @ppos: The position in the file to start reading from.
553  *
554  * Description:
555  * This routine reads value of variable reset_stats
556  * and stores into local @buf. It will start reading file at @ppos and
557  * copy up to @cnt of data to @ubuf from @buf.
558  *
559  * Returns:
560  * This function returns the amount of data that was read.
561  */
562 static ssize_t fnic_reset_stats_read(struct file *file,
563 					char __user *ubuf,
564 					size_t cnt, loff_t *ppos)
565 {
566 	struct stats_debug_info *debug = file->private_data;
567 	struct fnic *fnic = (struct fnic *)debug->i_private;
568 	char buf[64];
569 	int len;
570 
571 	len = sprintf(buf, "%u\n", fnic->reset_stats);
572 
573 	return simple_read_from_buffer(ubuf, cnt, ppos, buf, len);
574 }
575 
576 /*
577  * fnic_reset_stats_write - Write to reset_stats debugfs file
578  * @filp: The file pointer to write from.
579  * @ubuf: The buffer to copy the data from.
580  * @cnt: The number of bytes to write.
581  * @ppos: The position in the file to start writing to.
582  *
583  * Description:
584  * This routine writes data from user buffer @ubuf to buffer @buf and
585  * resets cumulative stats of fnic.
586  *
587  * Returns:
588  * This function returns the amount of data that was written.
589  */
590 static ssize_t fnic_reset_stats_write(struct file *file,
591 					const char __user *ubuf,
592 					size_t cnt, loff_t *ppos)
593 {
594 	struct stats_debug_info *debug = file->private_data;
595 	struct fnic *fnic = (struct fnic *)debug->i_private;
596 	struct fnic_stats *stats = &fnic->fnic_stats;
597 	u64 *io_stats_p = (u64 *)&stats->io_stats;
598 	u64 *fw_stats_p = (u64 *)&stats->fw_stats;
599 	char buf[64];
600 	unsigned long val;
601 	int ret;
602 
603 	if (cnt >= sizeof(buf))
604 		return -EINVAL;
605 
606 	if (copy_from_user(&buf, ubuf, cnt))
607 		return -EFAULT;
608 
609 	buf[cnt] = 0;
610 
611 	ret = kstrtoul(buf, 10, &val);
612 	if (ret < 0)
613 		return ret;
614 
615 	fnic->reset_stats = val;
616 
617 	if (fnic->reset_stats) {
618 		/* Skip variable is used to avoid descrepancies to Num IOs
619 		 * and IO Completions stats. Skip incrementing No IO Compls
620 		 * for pending active IOs after reset stats
621 		 */
622 		atomic64_set(&fnic->io_cmpl_skip,
623 			atomic64_read(&stats->io_stats.active_ios));
624 		memset(&stats->abts_stats, 0, sizeof(struct abort_stats));
625 		memset(&stats->term_stats, 0,
626 			sizeof(struct terminate_stats));
627 		memset(&stats->reset_stats, 0, sizeof(struct reset_stats));
628 		memset(&stats->misc_stats, 0, sizeof(struct misc_stats));
629 		memset(&stats->vlan_stats, 0, sizeof(struct vlan_stats));
630 		memset(io_stats_p+1, 0,
631 			sizeof(struct io_path_stats) - sizeof(u64));
632 		memset(fw_stats_p+1, 0,
633 			sizeof(struct fw_stats) - sizeof(u64));
634 	}
635 
636 	(*ppos)++;
637 	return cnt;
638 }
639 
640 /*
641  * fnic_reset_stats_release - Release the buffer used to store
642  * debugfs file data
643  * @inode: The inode pointer
644  * @file: The file pointer that contains the buffer to release
645  *
646  * Description:
647  * This routine frees the buffer that was allocated when the debugfs
648  * file was opened.
649  *
650  * Returns:
651  * This function returns zero.
652  */
653 static int fnic_reset_stats_release(struct inode *inode,
654 					struct file *file)
655 {
656 	struct stats_debug_info *debug = file->private_data;
657 	kfree(debug);
658 	return 0;
659 }
660 
661 /*
662  * fnic_stats_debugfs_open - Open the stats file for specific host
663  * and get fnic stats.
664  * @inode: The inode pointer.
665  * @file: The file pointer to attach the specific host statistics.
666  *
667  * Description:
668  * This routine opens a debugsfs file stats of specific host and print
669  * fnic stats.
670  *
671  * Returns:
672  * This function returns zero if successful.
673  */
674 static int fnic_stats_debugfs_open(struct inode *inode,
675 					struct file *file)
676 {
677 	struct fnic *fnic = inode->i_private;
678 	struct fnic_stats *fnic_stats = &fnic->fnic_stats;
679 	struct stats_debug_info *debug;
680 	int buf_size = 2 * PAGE_SIZE;
681 
682 	debug = kzalloc(sizeof(struct stats_debug_info), GFP_KERNEL);
683 	if (!debug)
684 		return -ENOMEM;
685 
686 	debug->debug_buffer = vmalloc(buf_size);
687 	if (!debug->debug_buffer) {
688 		kfree(debug);
689 		return -ENOMEM;
690 	}
691 
692 	debug->buf_size = buf_size;
693 	memset((void *)debug->debug_buffer, 0, buf_size);
694 	debug->buffer_len = fnic_get_stats_data(debug, fnic_stats);
695 
696 	file->private_data = debug;
697 
698 	return 0;
699 }
700 
701 /*
702  * fnic_stats_debugfs_read - Read a debugfs file
703  * @file: The file pointer to read from.
704  * @ubuf: The buffer to copy the data to.
705  * @nbytes: The number of bytes to read.
706  * @pos: The position in the file to start reading from.
707  *
708  * Description:
709  * This routine reads data from the buffer indicated in the private_data
710  * field of @file. It will start reading at @pos and copy up to @nbytes of
711  * data to @ubuf.
712  *
713  * Returns:
714  * This function returns the amount of data that was read (this could be
715  * less than @nbytes if the end of the file was reached).
716  */
717 static ssize_t fnic_stats_debugfs_read(struct file *file,
718 					char __user *ubuf,
719 					size_t nbytes,
720 					loff_t *pos)
721 {
722 	struct stats_debug_info *debug = file->private_data;
723 	int rc = 0;
724 	rc = simple_read_from_buffer(ubuf, nbytes, pos,
725 					debug->debug_buffer,
726 					debug->buffer_len);
727 	return rc;
728 }
729 
730 /*
731  * fnic_stats_stats_release - Release the buffer used to store
732  * debugfs file data
733  * @inode: The inode pointer
734  * @file: The file pointer that contains the buffer to release
735  *
736  * Description:
737  * This routine frees the buffer that was allocated when the debugfs
738  * file was opened.
739  *
740  * Returns:
741  * This function returns zero.
742  */
743 static int fnic_stats_debugfs_release(struct inode *inode,
744 					struct file *file)
745 {
746 	struct stats_debug_info *debug = file->private_data;
747 	vfree(debug->debug_buffer);
748 	kfree(debug);
749 	return 0;
750 }
751 
752 static const struct file_operations fnic_stats_debugfs_fops = {
753 	.owner = THIS_MODULE,
754 	.open = fnic_stats_debugfs_open,
755 	.read = fnic_stats_debugfs_read,
756 	.release = fnic_stats_debugfs_release,
757 };
758 
759 static const struct file_operations fnic_reset_debugfs_fops = {
760 	.owner = THIS_MODULE,
761 	.open = fnic_reset_stats_open,
762 	.read = fnic_reset_stats_read,
763 	.write = fnic_reset_stats_write,
764 	.release = fnic_reset_stats_release,
765 };
766 
767 /*
768  * fnic_stats_init - Initialize stats struct and create stats file per fnic
769  *
770  * Description:
771  * When Debugfs is configured this routine sets up the stats file per fnic
772  * It will create file stats and reset_stats under statistics/host# directory
773  * to log per fnic stats.
774  */
775 int fnic_stats_debugfs_init(struct fnic *fnic)
776 {
777 	int rc = -1;
778 	char name[16];
779 
780 	snprintf(name, sizeof(name), "host%d", fnic->lport->host->host_no);
781 
782 	if (!fnic_stats_debugfs_root) {
783 		printk(KERN_DEBUG "fnic_stats root doesn't exist\n");
784 		return rc;
785 	}
786 	fnic->fnic_stats_debugfs_host = debugfs_create_dir(name,
787 						fnic_stats_debugfs_root);
788 	if (!fnic->fnic_stats_debugfs_host) {
789 		printk(KERN_DEBUG "Cannot create host directory\n");
790 		return rc;
791 	}
792 
793 	fnic->fnic_stats_debugfs_file = debugfs_create_file("stats",
794 						S_IFREG|S_IRUGO|S_IWUSR,
795 						fnic->fnic_stats_debugfs_host,
796 						fnic,
797 						&fnic_stats_debugfs_fops);
798 	if (!fnic->fnic_stats_debugfs_file) {
799 		printk(KERN_DEBUG "Cannot create host stats file\n");
800 		return rc;
801 	}
802 
803 	fnic->fnic_reset_debugfs_file = debugfs_create_file("reset_stats",
804 						S_IFREG|S_IRUGO|S_IWUSR,
805 						fnic->fnic_stats_debugfs_host,
806 						fnic,
807 						&fnic_reset_debugfs_fops);
808 	if (!fnic->fnic_reset_debugfs_file) {
809 		printk(KERN_DEBUG "Cannot create host stats file\n");
810 		return rc;
811 	}
812 	rc = 0;
813 	return rc;
814 }
815 
816 /*
817  * fnic_stats_debugfs_remove - Tear down debugfs infrastructure of stats
818  *
819  * Description:
820  * When Debugfs is configured this routine removes debugfs file system
821  * elements that are specific to fnic stats.
822  */
823 void fnic_stats_debugfs_remove(struct fnic *fnic)
824 {
825 	if (!fnic)
826 		return;
827 
828 	debugfs_remove(fnic->fnic_stats_debugfs_file);
829 	fnic->fnic_stats_debugfs_file = NULL;
830 
831 	debugfs_remove(fnic->fnic_reset_debugfs_file);
832 	fnic->fnic_reset_debugfs_file = NULL;
833 
834 	debugfs_remove(fnic->fnic_stats_debugfs_host);
835 	fnic->fnic_stats_debugfs_host = NULL;
836 }
837