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 * Copyright 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
31static struct proc_dir_entry *dasd_proc_root_entry = NULL;
32static struct proc_dir_entry *dasd_devices_entry = NULL;
33static struct proc_dir_entry *dasd_statistics_entry = NULL;
34
35static int
36dasd_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(ptr: 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, fmt: "%s", dev_name(dev: &device->cdev->dev));
53 /* Print discipline string. */
54 if (device->discipline != NULL)
55 seq_printf(m, fmt: "(%s)", device->discipline->name);
56 else
57 seq_printf(m, fmt: "(none)");
58 /* Print kdev. */
59 if (block->gdp)
60 seq_printf(m, fmt: " at (%3d:%6d)",
61 MAJOR(disk_devt(block->gdp)),
62 MINOR(disk_devt(block->gdp)));
63 else
64 seq_printf(m, fmt: " at (???:??????)");
65 /* Print device name. */
66 if (block->gdp)
67 seq_printf(m, fmt: " is %-8s", block->gdp->disk_name);
68 else
69 seq_printf(m, fmt: " is ????????");
70 /* Print devices features. */
71 substr = (device->features & DASD_FEATURE_READONLY) ? "(ro)" : " ";
72 seq_printf(m, fmt: "%4s: ", substr);
73 /* Print device status information. */
74 switch (device->state) {
75 case DASD_STATE_NEW:
76 seq_printf(m, fmt: "new");
77 break;
78 case DASD_STATE_KNOWN:
79 seq_printf(m, fmt: "detected");
80 break;
81 case DASD_STATE_BASIC:
82 seq_printf(m, fmt: "basic");
83 break;
84 case DASD_STATE_UNFMT:
85 seq_printf(m, fmt: "unformatted");
86 break;
87 case DASD_STATE_READY:
88 case DASD_STATE_ONLINE:
89 seq_printf(m, fmt: "active ");
90 if (dasd_check_blocksize(bsize: block->bp_block))
91 seq_printf(m, fmt: "n/f ");
92 else
93 seq_printf(m,
94 fmt: "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, fmt: "no stat");
101 break;
102 }
103 dasd_put_device(device);
104 if (dasd_probeonly)
105 seq_printf(m, fmt: "(probeonly)");
106 seq_printf(m, fmt: "\n");
107 return 0;
108}
109
110static 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
117static 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
123static void dasd_devices_stop(struct seq_file *m, void *v)
124{
125}
126
127static 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#ifdef CONFIG_DASD_PROFILE
135static int dasd_stats_all_block_on(void)
136{
137 int i, rc;
138 struct dasd_device *device;
139
140 rc = 0;
141 for (i = 0; i < dasd_max_devindex; ++i) {
142 device = dasd_device_from_devindex(i);
143 if (IS_ERR(device))
144 continue;
145 if (device->block)
146 rc = dasd_profile_on(&device->block->profile);
147 dasd_put_device(device);
148 if (rc)
149 return rc;
150 }
151 return 0;
152}
153
154static void dasd_stats_all_block_off(void)
155{
156 int i;
157 struct dasd_device *device;
158
159 for (i = 0; i < dasd_max_devindex; ++i) {
160 device = dasd_device_from_devindex(i);
161 if (IS_ERR(device))
162 continue;
163 if (device->block)
164 dasd_profile_off(&device->block->profile);
165 dasd_put_device(device);
166 }
167}
168
169static void dasd_stats_all_block_reset(void)
170{
171 int i;
172 struct dasd_device *device;
173
174 for (i = 0; i < dasd_max_devindex; ++i) {
175 device = dasd_device_from_devindex(i);
176 if (IS_ERR(device))
177 continue;
178 if (device->block)
179 dasd_profile_reset(&device->block->profile);
180 dasd_put_device(device);
181 }
182}
183
184static void dasd_statistics_array(struct seq_file *m, unsigned int *array, int factor)
185{
186 int i;
187
188 for (i = 0; i < 32; i++) {
189 seq_printf(m, "%7d ", array[i] / factor);
190 if (i == 15)
191 seq_putc(m, '\n');
192 }
193 seq_putc(m, '\n');
194}
195#endif /* CONFIG_DASD_PROFILE */
196
197static int dasd_stats_proc_show(struct seq_file *m, void *v)
198{
199#ifdef CONFIG_DASD_PROFILE
200 struct dasd_profile_info *prof;
201 int factor;
202
203 spin_lock_bh(&dasd_global_profile.lock);
204 prof = dasd_global_profile.data;
205 if (!prof) {
206 spin_unlock_bh(&dasd_global_profile.lock);
207 seq_printf(m, "Statistics are off - they might be "
208 "switched on using 'echo set on > "
209 "/proc/dasd/statistics'\n");
210 return 0;
211 }
212
213 /* prevent counter 'overflow' on output */
214 for (factor = 1; (prof->dasd_io_reqs / factor) > 9999999;
215 factor *= 10);
216
217 seq_printf(m, "%d dasd I/O requests\n", prof->dasd_io_reqs);
218 seq_printf(m, "with %u sectors(512B each)\n",
219 prof->dasd_io_sects);
220 seq_printf(m, "Scale Factor is %d\n", factor);
221 seq_printf(m,
222 " __<4 ___8 __16 __32 __64 _128 "
223 " _256 _512 __1k __2k __4k __8k "
224 " _16k _32k _64k 128k\n");
225 seq_printf(m,
226 " _256 _512 __1M __2M __4M __8M "
227 " _16M _32M _64M 128M 256M 512M "
228 " __1G __2G __4G " " _>4G\n");
229
230 seq_printf(m, "Histogram of sizes (512B secs)\n");
231 dasd_statistics_array(m, prof->dasd_io_secs, factor);
232 seq_printf(m, "Histogram of I/O times (microseconds)\n");
233 dasd_statistics_array(m, prof->dasd_io_times, factor);
234 seq_printf(m, "Histogram of I/O times per sector\n");
235 dasd_statistics_array(m, prof->dasd_io_timps, factor);
236 seq_printf(m, "Histogram of I/O time till ssch\n");
237 dasd_statistics_array(m, prof->dasd_io_time1, factor);
238 seq_printf(m, "Histogram of I/O time between ssch and irq\n");
239 dasd_statistics_array(m, prof->dasd_io_time2, factor);
240 seq_printf(m, "Histogram of I/O time between ssch "
241 "and irq per sector\n");
242 dasd_statistics_array(m, prof->dasd_io_time2ps, factor);
243 seq_printf(m, "Histogram of I/O time between irq and end\n");
244 dasd_statistics_array(m, prof->dasd_io_time3, factor);
245 seq_printf(m, "# of req in chanq at enqueuing (1..32) \n");
246 dasd_statistics_array(m, prof->dasd_io_nr_req, factor);
247 spin_unlock_bh(&dasd_global_profile.lock);
248#else
249 seq_printf(m, fmt: "Statistics are not activated in this kernel\n");
250#endif
251 return 0;
252}
253
254static int dasd_stats_proc_open(struct inode *inode, struct file *file)
255{
256 return single_open(file, dasd_stats_proc_show, NULL);
257}
258
259static ssize_t dasd_stats_proc_write(struct file *file,
260 const char __user *user_buf, size_t user_len, loff_t *pos)
261{
262#ifdef CONFIG_DASD_PROFILE
263 char *buffer, *str;
264 int rc;
265
266 if (user_len > 65536)
267 user_len = 65536;
268 buffer = dasd_get_user_string(user_buf, user_len);
269 if (IS_ERR(buffer))
270 return PTR_ERR(buffer);
271
272 /* check for valid verbs */
273 str = skip_spaces(buffer);
274 if (strncmp(str, "set", 3) == 0 && isspace(str[3])) {
275 /* 'set xxx' was given */
276 str = skip_spaces(str + 4);
277 if (strcmp(str, "on") == 0) {
278 /* switch on statistics profiling */
279 rc = dasd_stats_all_block_on();
280 if (rc) {
281 dasd_stats_all_block_off();
282 goto out_error;
283 }
284 rc = dasd_profile_on(&dasd_global_profile);
285 if (rc) {
286 dasd_stats_all_block_off();
287 goto out_error;
288 }
289 dasd_profile_reset(&dasd_global_profile);
290 dasd_global_profile_level = DASD_PROFILE_ON;
291 pr_info("The statistics feature has been switched "
292 "on\n");
293 } else if (strcmp(str, "off") == 0) {
294 /* switch off statistics profiling */
295 dasd_global_profile_level = DASD_PROFILE_OFF;
296 dasd_profile_off(&dasd_global_profile);
297 dasd_stats_all_block_off();
298 pr_info("The statistics feature has been switched "
299 "off\n");
300 } else
301 goto out_parse_error;
302 } else if (strncmp(str, "reset", 5) == 0) {
303 /* reset the statistics */
304 dasd_profile_reset(&dasd_global_profile);
305 dasd_stats_all_block_reset();
306 pr_info("The statistics have been reset\n");
307 } else
308 goto out_parse_error;
309 vfree(buffer);
310 return user_len;
311out_parse_error:
312 rc = -EINVAL;
313 pr_warn("%s is not a supported value for /proc/dasd/statistics\n", str);
314out_error:
315 vfree(buffer);
316 return rc;
317#else
318 pr_warn("/proc/dasd/statistics: is not activated in this kernel\n");
319 return user_len;
320#endif /* CONFIG_DASD_PROFILE */
321}
322
323static const struct proc_ops dasd_stats_proc_ops = {
324 .proc_open = dasd_stats_proc_open,
325 .proc_read = seq_read,
326 .proc_lseek = seq_lseek,
327 .proc_release = single_release,
328 .proc_write = dasd_stats_proc_write,
329};
330
331/*
332 * Create dasd proc-fs entries.
333 * In case creation failed, cleanup and return -ENOENT.
334 */
335int
336dasd_proc_init(void)
337{
338 dasd_proc_root_entry = proc_mkdir("dasd", NULL);
339 if (!dasd_proc_root_entry)
340 goto out_nodasd;
341 dasd_devices_entry = proc_create_seq("devices", 0444,
342 dasd_proc_root_entry,
343 &dasd_devices_seq_ops);
344 if (!dasd_devices_entry)
345 goto out_nodevices;
346 dasd_statistics_entry = proc_create(name: "statistics",
347 S_IFREG | S_IRUGO | S_IWUSR,
348 parent: dasd_proc_root_entry,
349 proc_ops: &dasd_stats_proc_ops);
350 if (!dasd_statistics_entry)
351 goto out_nostatistics;
352 return 0;
353
354 out_nostatistics:
355 remove_proc_entry("devices", dasd_proc_root_entry);
356 out_nodevices:
357 remove_proc_entry("dasd", NULL);
358 out_nodasd:
359 return -ENOENT;
360}
361
362void
363dasd_proc_exit(void)
364{
365 remove_proc_entry("devices", dasd_proc_root_entry);
366 remove_proc_entry("statistics", dasd_proc_root_entry);
367 remove_proc_entry("dasd", NULL);
368}
369

source code of linux/drivers/s390/block/dasd_proc.c