xref: /openbmc/linux/drivers/s390/block/dasd_proc.c (revision feac8c8b)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
4  *		    Horst Hummel <Horst.Hummel@de.ibm.com>
5  *		    Carsten Otte <Cotte@de.ibm.com>
6  *		    Martin Schwidefsky <schwidefsky@de.ibm.com>
7  * Bugreports.to..: <Linux390@de.ibm.com>
8  * Coypright IBM Corp. 1999, 2002
9  *
10  * /proc interface for the dasd driver.
11  *
12  */
13 
14 #define KMSG_COMPONENT "dasd"
15 
16 #include <linux/ctype.h>
17 #include <linux/slab.h>
18 #include <linux/string.h>
19 #include <linux/seq_file.h>
20 #include <linux/vmalloc.h>
21 #include <linux/proc_fs.h>
22 
23 #include <asm/debug.h>
24 #include <linux/uaccess.h>
25 
26 /* This is ugly... */
27 #define PRINTK_HEADER "dasd_proc:"
28 
29 #include "dasd_int.h"
30 
31 static struct proc_dir_entry *dasd_proc_root_entry = NULL;
32 static struct proc_dir_entry *dasd_devices_entry = NULL;
33 static struct proc_dir_entry *dasd_statistics_entry = NULL;
34 
35 static int
36 dasd_devices_show(struct seq_file *m, void *v)
37 {
38 	struct dasd_device *device;
39 	struct dasd_block *block;
40 	char *substr;
41 
42 	device = dasd_device_from_devindex((unsigned long) v - 1);
43 	if (IS_ERR(device))
44 		return 0;
45 	if (device->block)
46 		block = device->block;
47 	else {
48 		dasd_put_device(device);
49 		return 0;
50 	}
51 	/* Print device number. */
52 	seq_printf(m, "%s", dev_name(&device->cdev->dev));
53 	/* Print discipline string. */
54 	if (device->discipline != NULL)
55 		seq_printf(m, "(%s)", device->discipline->name);
56 	else
57 		seq_printf(m, "(none)");
58 	/* Print kdev. */
59 	if (block->gdp)
60 		seq_printf(m, " at (%3d:%6d)",
61 			   MAJOR(disk_devt(block->gdp)),
62 			   MINOR(disk_devt(block->gdp)));
63 	else
64 		seq_printf(m, "  at (???:??????)");
65 	/* Print device name. */
66 	if (block->gdp)
67 		seq_printf(m, " is %-8s", block->gdp->disk_name);
68 	else
69 		seq_printf(m, " is ????????");
70 	/* Print devices features. */
71 	substr = (device->features & DASD_FEATURE_READONLY) ? "(ro)" : " ";
72 	seq_printf(m, "%4s: ", substr);
73 	/* Print device status information. */
74 	switch (device->state) {
75 	case DASD_STATE_NEW:
76 		seq_printf(m, "new");
77 		break;
78 	case DASD_STATE_KNOWN:
79 		seq_printf(m, "detected");
80 		break;
81 	case DASD_STATE_BASIC:
82 		seq_printf(m, "basic");
83 		break;
84 	case DASD_STATE_UNFMT:
85 		seq_printf(m, "unformatted");
86 		break;
87 	case DASD_STATE_READY:
88 	case DASD_STATE_ONLINE:
89 		seq_printf(m, "active ");
90 		if (dasd_check_blocksize(block->bp_block))
91 			seq_printf(m, "n/f	 ");
92 		else
93 			seq_printf(m,
94 				   "at blocksize: %u, %lu blocks, %lu MB",
95 				   block->bp_block, block->blocks,
96 				   ((block->bp_block >> 9) *
97 				    block->blocks) >> 11);
98 		break;
99 	default:
100 		seq_printf(m, "no stat");
101 		break;
102 	}
103 	dasd_put_device(device);
104 	if (dasd_probeonly)
105 		seq_printf(m, "(probeonly)");
106 	seq_printf(m, "\n");
107 	return 0;
108 }
109 
110 static void *dasd_devices_start(struct seq_file *m, loff_t *pos)
111 {
112 	if (*pos >= dasd_max_devindex)
113 		return NULL;
114 	return (void *)((unsigned long) *pos + 1);
115 }
116 
117 static void *dasd_devices_next(struct seq_file *m, void *v, loff_t *pos)
118 {
119 	++*pos;
120 	return dasd_devices_start(m, pos);
121 }
122 
123 static void dasd_devices_stop(struct seq_file *m, void *v)
124 {
125 }
126 
127 static const struct seq_operations dasd_devices_seq_ops = {
128 	.start		= dasd_devices_start,
129 	.next		= dasd_devices_next,
130 	.stop		= dasd_devices_stop,
131 	.show		= dasd_devices_show,
132 };
133 
134 static int dasd_devices_open(struct inode *inode, struct file *file)
135 {
136 	return seq_open(file, &dasd_devices_seq_ops);
137 }
138 
139 static const struct file_operations dasd_devices_file_ops = {
140 	.owner		= THIS_MODULE,
141 	.open		= dasd_devices_open,
142 	.read		= seq_read,
143 	.llseek		= seq_lseek,
144 	.release	= seq_release,
145 };
146 
147 #ifdef CONFIG_DASD_PROFILE
148 static int dasd_stats_all_block_on(void)
149 {
150 	int i, rc;
151 	struct dasd_device *device;
152 
153 	rc = 0;
154 	for (i = 0; i < dasd_max_devindex; ++i) {
155 		device = dasd_device_from_devindex(i);
156 		if (IS_ERR(device))
157 			continue;
158 		if (device->block)
159 			rc = dasd_profile_on(&device->block->profile);
160 		dasd_put_device(device);
161 		if (rc)
162 			return rc;
163 	}
164 	return 0;
165 }
166 
167 static void dasd_stats_all_block_off(void)
168 {
169 	int i;
170 	struct dasd_device *device;
171 
172 	for (i = 0; i < dasd_max_devindex; ++i) {
173 		device = dasd_device_from_devindex(i);
174 		if (IS_ERR(device))
175 			continue;
176 		if (device->block)
177 			dasd_profile_off(&device->block->profile);
178 		dasd_put_device(device);
179 	}
180 }
181 
182 static void dasd_stats_all_block_reset(void)
183 {
184 	int i;
185 	struct dasd_device *device;
186 
187 	for (i = 0; i < dasd_max_devindex; ++i) {
188 		device = dasd_device_from_devindex(i);
189 		if (IS_ERR(device))
190 			continue;
191 		if (device->block)
192 			dasd_profile_reset(&device->block->profile);
193 		dasd_put_device(device);
194 	}
195 }
196 
197 static void dasd_statistics_array(struct seq_file *m, unsigned int *array, int factor)
198 {
199 	int i;
200 
201 	for (i = 0; i < 32; i++) {
202 		seq_printf(m, "%7d ", array[i] / factor);
203 		if (i == 15)
204 			seq_putc(m, '\n');
205 	}
206 	seq_putc(m, '\n');
207 }
208 #endif /* CONFIG_DASD_PROFILE */
209 
210 static int dasd_stats_proc_show(struct seq_file *m, void *v)
211 {
212 #ifdef CONFIG_DASD_PROFILE
213 	struct dasd_profile_info *prof;
214 	int factor;
215 
216 	spin_lock_bh(&dasd_global_profile.lock);
217 	prof = dasd_global_profile.data;
218 	if (!prof) {
219 		spin_unlock_bh(&dasd_global_profile.lock);
220 		seq_printf(m, "Statistics are off - they might be "
221 				    "switched on using 'echo set on > "
222 				    "/proc/dasd/statistics'\n");
223 		return 0;
224 	}
225 
226 	/* prevent counter 'overflow' on output */
227 	for (factor = 1; (prof->dasd_io_reqs / factor) > 9999999;
228 	     factor *= 10);
229 
230 	seq_printf(m, "%d dasd I/O requests\n", prof->dasd_io_reqs);
231 	seq_printf(m, "with %u sectors(512B each)\n",
232 		       prof->dasd_io_sects);
233 	seq_printf(m, "Scale Factor is  %d\n", factor);
234 	seq_printf(m,
235 		       "   __<4	   ___8	   __16	   __32	   __64	   _128	"
236 		       "   _256	   _512	   __1k	   __2k	   __4k	   __8k	"
237 		       "   _16k	   _32k	   _64k	   128k\n");
238 	seq_printf(m,
239 		       "   _256	   _512	   __1M	   __2M	   __4M	   __8M	"
240 		       "   _16M	   _32M	   _64M	   128M	   256M	   512M	"
241 		       "   __1G	   __2G	   __4G " "   _>4G\n");
242 
243 	seq_printf(m, "Histogram of sizes (512B secs)\n");
244 	dasd_statistics_array(m, prof->dasd_io_secs, factor);
245 	seq_printf(m, "Histogram of I/O times (microseconds)\n");
246 	dasd_statistics_array(m, prof->dasd_io_times, factor);
247 	seq_printf(m, "Histogram of I/O times per sector\n");
248 	dasd_statistics_array(m, prof->dasd_io_timps, factor);
249 	seq_printf(m, "Histogram of I/O time till ssch\n");
250 	dasd_statistics_array(m, prof->dasd_io_time1, factor);
251 	seq_printf(m, "Histogram of I/O time between ssch and irq\n");
252 	dasd_statistics_array(m, prof->dasd_io_time2, factor);
253 	seq_printf(m, "Histogram of I/O time between ssch "
254 			    "and irq per sector\n");
255 	dasd_statistics_array(m, prof->dasd_io_time2ps, factor);
256 	seq_printf(m, "Histogram of I/O time between irq and end\n");
257 	dasd_statistics_array(m, prof->dasd_io_time3, factor);
258 	seq_printf(m, "# of req in chanq at enqueuing (1..32) \n");
259 	dasd_statistics_array(m, prof->dasd_io_nr_req, factor);
260 	spin_unlock_bh(&dasd_global_profile.lock);
261 #else
262 	seq_printf(m, "Statistics are not activated in this kernel\n");
263 #endif
264 	return 0;
265 }
266 
267 static int dasd_stats_proc_open(struct inode *inode, struct file *file)
268 {
269 	return single_open(file, dasd_stats_proc_show, NULL);
270 }
271 
272 static ssize_t dasd_stats_proc_write(struct file *file,
273 		const char __user *user_buf, size_t user_len, loff_t *pos)
274 {
275 #ifdef CONFIG_DASD_PROFILE
276 	char *buffer, *str;
277 	int rc;
278 
279 	if (user_len > 65536)
280 		user_len = 65536;
281 	buffer = dasd_get_user_string(user_buf, user_len);
282 	if (IS_ERR(buffer))
283 		return PTR_ERR(buffer);
284 
285 	/* check for valid verbs */
286 	str = skip_spaces(buffer);
287 	if (strncmp(str, "set", 3) == 0 && isspace(str[3])) {
288 		/* 'set xxx' was given */
289 		str = skip_spaces(str + 4);
290 		if (strcmp(str, "on") == 0) {
291 			/* switch on statistics profiling */
292 			rc = dasd_stats_all_block_on();
293 			if (rc) {
294 				dasd_stats_all_block_off();
295 				goto out_error;
296 			}
297 			rc = dasd_profile_on(&dasd_global_profile);
298 			if (rc) {
299 				dasd_stats_all_block_off();
300 				goto out_error;
301 			}
302 			dasd_profile_reset(&dasd_global_profile);
303 			dasd_global_profile_level = DASD_PROFILE_ON;
304 			pr_info("The statistics feature has been switched "
305 				"on\n");
306 		} else if (strcmp(str, "off") == 0) {
307 			/* switch off statistics profiling */
308 			dasd_global_profile_level = DASD_PROFILE_OFF;
309 			dasd_profile_off(&dasd_global_profile);
310 			dasd_stats_all_block_off();
311 			pr_info("The statistics feature has been switched "
312 				"off\n");
313 		} else
314 			goto out_parse_error;
315 	} else if (strncmp(str, "reset", 5) == 0) {
316 		/* reset the statistics */
317 		dasd_profile_reset(&dasd_global_profile);
318 		dasd_stats_all_block_reset();
319 		pr_info("The statistics have been reset\n");
320 	} else
321 		goto out_parse_error;
322 	vfree(buffer);
323 	return user_len;
324 out_parse_error:
325 	rc = -EINVAL;
326 	pr_warn("%s is not a supported value for /proc/dasd/statistics\n", str);
327 out_error:
328 	vfree(buffer);
329 	return rc;
330 #else
331 	pr_warn("/proc/dasd/statistics: is not activated in this kernel\n");
332 	return user_len;
333 #endif				/* CONFIG_DASD_PROFILE */
334 }
335 
336 static const struct file_operations dasd_stats_proc_fops = {
337 	.owner		= THIS_MODULE,
338 	.open		= dasd_stats_proc_open,
339 	.read		= seq_read,
340 	.llseek		= seq_lseek,
341 	.release	= single_release,
342 	.write		= dasd_stats_proc_write,
343 };
344 
345 /*
346  * Create dasd proc-fs entries.
347  * In case creation failed, cleanup and return -ENOENT.
348  */
349 int
350 dasd_proc_init(void)
351 {
352 	dasd_proc_root_entry = proc_mkdir("dasd", NULL);
353 	if (!dasd_proc_root_entry)
354 		goto out_nodasd;
355 	dasd_devices_entry = proc_create("devices",
356 					 S_IFREG | S_IRUGO | S_IWUSR,
357 					 dasd_proc_root_entry,
358 					 &dasd_devices_file_ops);
359 	if (!dasd_devices_entry)
360 		goto out_nodevices;
361 	dasd_statistics_entry = proc_create("statistics",
362 					    S_IFREG | S_IRUGO | S_IWUSR,
363 					    dasd_proc_root_entry,
364 					    &dasd_stats_proc_fops);
365 	if (!dasd_statistics_entry)
366 		goto out_nostatistics;
367 	return 0;
368 
369  out_nostatistics:
370 	remove_proc_entry("devices", dasd_proc_root_entry);
371  out_nodevices:
372 	remove_proc_entry("dasd", NULL);
373  out_nodasd:
374 	return -ENOENT;
375 }
376 
377 void
378 dasd_proc_exit(void)
379 {
380 	remove_proc_entry("devices", dasd_proc_root_entry);
381 	remove_proc_entry("statistics", dasd_proc_root_entry);
382 	remove_proc_entry("dasd", NULL);
383 }
384