GNU Linux-libre 4.14.266-gnu1
[releases.git] / drivers / s390 / block / dasd_proc.c
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 }