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
dasd_devices_show(struct seq_file * m,void * v)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 
dasd_devices_start(struct seq_file * m,loff_t * pos)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 
dasd_devices_next(struct seq_file * m,void * v,loff_t * pos)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 
dasd_devices_stop(struct seq_file * m,void * v)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 #ifdef CONFIG_DASD_PROFILE
dasd_stats_all_block_on(void)135 static 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 
dasd_stats_all_block_off(void)154 static 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 
dasd_stats_all_block_reset(void)169 static 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 
dasd_statistics_array(struct seq_file * m,unsigned int * array,int factor)184 static 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 
dasd_stats_proc_show(struct seq_file * m,void * v)197 static 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, "Statistics are not activated in this kernel\n");
250 #endif
251 	return 0;
252 }
253 
dasd_stats_proc_open(struct inode * inode,struct file * file)254 static int dasd_stats_proc_open(struct inode *inode, struct file *file)
255 {
256 	return single_open(file, dasd_stats_proc_show, NULL);
257 }
258 
dasd_stats_proc_write(struct file * file,const char __user * user_buf,size_t user_len,loff_t * pos)259 static 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;
311 out_parse_error:
312 	rc = -EINVAL;
313 	pr_warn("%s is not a supported value for /proc/dasd/statistics\n", str);
314 out_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 
323 static const struct file_operations dasd_stats_proc_fops = {
324 	.owner		= THIS_MODULE,
325 	.open		= dasd_stats_proc_open,
326 	.read		= seq_read,
327 	.llseek		= seq_lseek,
328 	.release	= single_release,
329 	.write		= dasd_stats_proc_write,
330 };
331 
332 /*
333  * Create dasd proc-fs entries.
334  * In case creation failed, cleanup and return -ENOENT.
335  */
336 int
dasd_proc_init(void)337 dasd_proc_init(void)
338 {
339 	dasd_proc_root_entry = proc_mkdir("dasd", NULL);
340 	if (!dasd_proc_root_entry)
341 		goto out_nodasd;
342 	dasd_devices_entry = proc_create_seq("devices",
343 					 S_IFREG | S_IRUGO | S_IWUSR,
344 					 dasd_proc_root_entry,
345 					 &dasd_devices_seq_ops);
346 	if (!dasd_devices_entry)
347 		goto out_nodevices;
348 	dasd_statistics_entry = proc_create("statistics",
349 					    S_IFREG | S_IRUGO | S_IWUSR,
350 					    dasd_proc_root_entry,
351 					    &dasd_stats_proc_fops);
352 	if (!dasd_statistics_entry)
353 		goto out_nostatistics;
354 	return 0;
355 
356  out_nostatistics:
357 	remove_proc_entry("devices", dasd_proc_root_entry);
358  out_nodevices:
359 	remove_proc_entry("dasd", NULL);
360  out_nodasd:
361 	return -ENOENT;
362 }
363 
364 void
dasd_proc_exit(void)365 dasd_proc_exit(void)
366 {
367 	remove_proc_entry("devices", dasd_proc_root_entry);
368 	remove_proc_entry("statistics", dasd_proc_root_entry);
369 	remove_proc_entry("dasd", NULL);
370 }
371