xref: /openbmc/linux/drivers/s390/block/dasd_proc.c (revision 7dd65feb)
1 /*
2  * File...........: linux/drivers/s390/block/dasd_proc.c
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  * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 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/string.h>
18 #include <linux/seq_file.h>
19 #include <linux/vmalloc.h>
20 #include <linux/proc_fs.h>
21 
22 #include <asm/debug.h>
23 #include <asm/uaccess.h>
24 
25 /* This is ugly... */
26 #define PRINTK_HEADER "dasd_proc:"
27 
28 #include "dasd_int.h"
29 
30 static struct proc_dir_entry *dasd_proc_root_entry = NULL;
31 static struct proc_dir_entry *dasd_devices_entry = NULL;
32 static struct proc_dir_entry *dasd_statistics_entry = NULL;
33 
34 #ifdef CONFIG_DASD_PROFILE
35 static char *
36 dasd_get_user_string(const char __user *user_buf, size_t user_len)
37 {
38 	char *buffer;
39 
40 	buffer = kmalloc(user_len + 1, GFP_KERNEL);
41 	if (buffer == NULL)
42 		return ERR_PTR(-ENOMEM);
43 	if (copy_from_user(buffer, user_buf, user_len) != 0) {
44 		kfree(buffer);
45 		return ERR_PTR(-EFAULT);
46 	}
47 	/* got the string, now strip linefeed. */
48 	if (buffer[user_len - 1] == '\n')
49 		buffer[user_len - 1] = 0;
50 	else
51 		buffer[user_len] = 0;
52 	return buffer;
53 }
54 #endif /* CONFIG_DASD_PROFILE */
55 
56 static int
57 dasd_devices_show(struct seq_file *m, void *v)
58 {
59 	struct dasd_device *device;
60 	struct dasd_block *block;
61 	char *substr;
62 
63 	device = dasd_device_from_devindex((unsigned long) v - 1);
64 	if (IS_ERR(device))
65 		return 0;
66 	if (device->block)
67 		block = device->block;
68 	else {
69 		dasd_put_device(device);
70 		return 0;
71 	}
72 	/* Print device number. */
73 	seq_printf(m, "%s", dev_name(&device->cdev->dev));
74 	/* Print discipline string. */
75 	if (device != NULL && device->discipline != NULL)
76 		seq_printf(m, "(%s)", device->discipline->name);
77 	else
78 		seq_printf(m, "(none)");
79 	/* Print kdev. */
80 	if (block->gdp)
81 		seq_printf(m, " at (%3d:%6d)",
82 			   MAJOR(disk_devt(block->gdp)),
83 			   MINOR(disk_devt(block->gdp)));
84 	else
85 		seq_printf(m, "  at (???:??????)");
86 	/* Print device name. */
87 	if (block->gdp)
88 		seq_printf(m, " is %-8s", block->gdp->disk_name);
89 	else
90 		seq_printf(m, " is ????????");
91 	/* Print devices features. */
92 	substr = (device->features & DASD_FEATURE_READONLY) ? "(ro)" : " ";
93 	seq_printf(m, "%4s: ", substr);
94 	/* Print device status information. */
95 	switch ((device != NULL) ? device->state : -1) {
96 	case -1:
97 		seq_printf(m, "unknown");
98 		break;
99 	case DASD_STATE_NEW:
100 		seq_printf(m, "new");
101 		break;
102 	case DASD_STATE_KNOWN:
103 		seq_printf(m, "detected");
104 		break;
105 	case DASD_STATE_BASIC:
106 		seq_printf(m, "basic");
107 		break;
108 	case DASD_STATE_UNFMT:
109 		seq_printf(m, "unformatted");
110 		break;
111 	case DASD_STATE_READY:
112 	case DASD_STATE_ONLINE:
113 		seq_printf(m, "active ");
114 		if (dasd_check_blocksize(block->bp_block))
115 			seq_printf(m, "n/f	 ");
116 		else
117 			seq_printf(m,
118 				   "at blocksize: %d, %lld blocks, %lld MB",
119 				   block->bp_block, block->blocks,
120 				   ((block->bp_block >> 9) *
121 				    block->blocks) >> 11);
122 		break;
123 	default:
124 		seq_printf(m, "no stat");
125 		break;
126 	}
127 	dasd_put_device(device);
128 	if (dasd_probeonly)
129 		seq_printf(m, "(probeonly)");
130 	seq_printf(m, "\n");
131 	return 0;
132 }
133 
134 static void *dasd_devices_start(struct seq_file *m, loff_t *pos)
135 {
136 	if (*pos >= dasd_max_devindex)
137 		return NULL;
138 	return (void *)((unsigned long) *pos + 1);
139 }
140 
141 static void *dasd_devices_next(struct seq_file *m, void *v, loff_t *pos)
142 {
143 	++*pos;
144 	return dasd_devices_start(m, pos);
145 }
146 
147 static void dasd_devices_stop(struct seq_file *m, void *v)
148 {
149 }
150 
151 static const struct seq_operations dasd_devices_seq_ops = {
152 	.start		= dasd_devices_start,
153 	.next		= dasd_devices_next,
154 	.stop		= dasd_devices_stop,
155 	.show		= dasd_devices_show,
156 };
157 
158 static int dasd_devices_open(struct inode *inode, struct file *file)
159 {
160 	return seq_open(file, &dasd_devices_seq_ops);
161 }
162 
163 static const struct file_operations dasd_devices_file_ops = {
164 	.owner		= THIS_MODULE,
165 	.open		= dasd_devices_open,
166 	.read		= seq_read,
167 	.llseek		= seq_lseek,
168 	.release	= seq_release,
169 };
170 
171 static int
172 dasd_calc_metrics(char *page, char **start, off_t off,
173 		  int count, int *eof, int len)
174 {
175 	len = (len > off) ? len - off : 0;
176 	if (len > count)
177 		len = count;
178 	if (len < count)
179 		*eof = 1;
180 	*start = page + off;
181 	return len;
182 }
183 
184 #ifdef CONFIG_DASD_PROFILE
185 static char *
186 dasd_statistics_array(char *str, unsigned int *array, int factor)
187 {
188 	int i;
189 
190 	for (i = 0; i < 32; i++) {
191 		str += sprintf(str, "%7d ", array[i] / factor);
192 		if (i == 15)
193 			str += sprintf(str, "\n");
194 	}
195 	str += sprintf(str,"\n");
196 	return str;
197 }
198 #endif /* CONFIG_DASD_PROFILE */
199 
200 static int
201 dasd_statistics_read(char *page, char **start, off_t off,
202 		     int count, int *eof, void *data)
203 {
204 	unsigned long len;
205 #ifdef CONFIG_DASD_PROFILE
206 	struct dasd_profile_info_t *prof;
207 	char *str;
208 	int factor;
209 
210 	/* check for active profiling */
211 	if (dasd_profile_level == DASD_PROFILE_OFF) {
212 		len = sprintf(page, "Statistics are off - they might be "
213 				    "switched on using 'echo set on > "
214 				    "/proc/dasd/statistics'\n");
215 		return dasd_calc_metrics(page, start, off, count, eof, len);
216 	}
217 
218 	prof = &dasd_global_profile;
219 	/* prevent counter 'overflow' on output */
220 	for (factor = 1; (prof->dasd_io_reqs / factor) > 9999999;
221 	     factor *= 10);
222 
223 	str = page;
224 	str += sprintf(str, "%d dasd I/O requests\n", prof->dasd_io_reqs);
225 	str += sprintf(str, "with %u sectors(512B each)\n",
226 		       prof->dasd_io_sects);
227 	str += sprintf(str, "Scale Factor is  %d\n", factor);
228 	str += sprintf(str,
229 		       "   __<4	   ___8	   __16	   __32	   __64	   _128	"
230 		       "   _256	   _512	   __1k	   __2k	   __4k	   __8k	"
231 		       "   _16k	   _32k	   _64k	   128k\n");
232 	str += sprintf(str,
233 		       "   _256	   _512	   __1M	   __2M	   __4M	   __8M	"
234 		       "   _16M	   _32M	   _64M	   128M	   256M	   512M	"
235 		       "   __1G	   __2G	   __4G " "   _>4G\n");
236 
237 	str += sprintf(str, "Histogram of sizes (512B secs)\n");
238 	str = dasd_statistics_array(str, prof->dasd_io_secs, factor);
239 	str += sprintf(str, "Histogram of I/O times (microseconds)\n");
240 	str = dasd_statistics_array(str, prof->dasd_io_times, factor);
241 	str += sprintf(str, "Histogram of I/O times per sector\n");
242 	str = dasd_statistics_array(str, prof->dasd_io_timps, factor);
243 	str += sprintf(str, "Histogram of I/O time till ssch\n");
244 	str = dasd_statistics_array(str, prof->dasd_io_time1, factor);
245 	str += sprintf(str, "Histogram of I/O time between ssch and irq\n");
246 	str = dasd_statistics_array(str, prof->dasd_io_time2, factor);
247 	str += sprintf(str, "Histogram of I/O time between ssch "
248 			    "and irq per sector\n");
249 	str = dasd_statistics_array(str, prof->dasd_io_time2ps, factor);
250 	str += sprintf(str, "Histogram of I/O time between irq and end\n");
251 	str = dasd_statistics_array(str, prof->dasd_io_time3, factor);
252 	str += sprintf(str, "# of req in chanq at enqueuing (1..32) \n");
253 	str = dasd_statistics_array(str, prof->dasd_io_nr_req, factor);
254 	len = str - page;
255 #else
256 	len = sprintf(page, "Statistics are not activated in this kernel\n");
257 #endif
258 	return dasd_calc_metrics(page, start, off, count, eof, len);
259 }
260 
261 static int
262 dasd_statistics_write(struct file *file, const char __user *user_buf,
263 		      unsigned long user_len, void *data)
264 {
265 #ifdef CONFIG_DASD_PROFILE
266 	char *buffer, *str;
267 
268 	if (user_len > 65536)
269 		user_len = 65536;
270 	buffer = dasd_get_user_string(user_buf, user_len);
271 	if (IS_ERR(buffer))
272 		return PTR_ERR(buffer);
273 	DBF_EVENT(DBF_DEBUG, "/proc/dasd/statictics: '%s'\n", buffer);
274 
275 	/* check for valid verbs */
276 	str = skip_spaces(buffer);
277 	if (strncmp(str, "set", 3) == 0 && isspace(str[3])) {
278 		/* 'set xxx' was given */
279 		str = skip_spaces(str + 4);
280 		if (strcmp(str, "on") == 0) {
281 			/* switch on statistics profiling */
282 			dasd_profile_level = DASD_PROFILE_ON;
283 			pr_info("The statistics feature has been switched "
284 				"on\n");
285 		} else if (strcmp(str, "off") == 0) {
286 			/* switch off and reset statistics profiling */
287 			memset(&dasd_global_profile,
288 			       0, sizeof (struct dasd_profile_info_t));
289 			dasd_profile_level = DASD_PROFILE_OFF;
290 			pr_info("The statistics feature has been switched "
291 				"off\n");
292 		} else
293 			goto out_error;
294 	} else if (strncmp(str, "reset", 5) == 0) {
295 		/* reset the statistics */
296 		memset(&dasd_global_profile, 0,
297 		       sizeof (struct dasd_profile_info_t));
298 		pr_info("The statistics have been reset\n");
299 	} else
300 		goto out_error;
301 	kfree(buffer);
302 	return user_len;
303 out_error:
304 	pr_warning("%s is not a supported value for /proc/dasd/statistics\n",
305 		str);
306 	kfree(buffer);
307 	return -EINVAL;
308 #else
309 	pr_warning("/proc/dasd/statistics: is not activated in this kernel\n");
310 	return user_len;
311 #endif				/* CONFIG_DASD_PROFILE */
312 }
313 
314 /*
315  * Create dasd proc-fs entries.
316  * In case creation failed, cleanup and return -ENOENT.
317  */
318 int
319 dasd_proc_init(void)
320 {
321 	dasd_proc_root_entry = proc_mkdir("dasd", NULL);
322 	if (!dasd_proc_root_entry)
323 		goto out_nodasd;
324 	dasd_devices_entry = proc_create("devices",
325 					 S_IFREG | S_IRUGO | S_IWUSR,
326 					 dasd_proc_root_entry,
327 					 &dasd_devices_file_ops);
328 	if (!dasd_devices_entry)
329 		goto out_nodevices;
330 	dasd_statistics_entry = create_proc_entry("statistics",
331 						  S_IFREG | S_IRUGO | S_IWUSR,
332 						  dasd_proc_root_entry);
333 	if (!dasd_statistics_entry)
334 		goto out_nostatistics;
335 	dasd_statistics_entry->read_proc = dasd_statistics_read;
336 	dasd_statistics_entry->write_proc = dasd_statistics_write;
337 	return 0;
338 
339  out_nostatistics:
340 	remove_proc_entry("devices", dasd_proc_root_entry);
341  out_nodevices:
342 	remove_proc_entry("dasd", NULL);
343  out_nodasd:
344 	return -ENOENT;
345 }
346 
347 void
348 dasd_proc_exit(void)
349 {
350 	remove_proc_entry("devices", dasd_proc_root_entry);
351 	remove_proc_entry("statistics", dasd_proc_root_entry);
352 	remove_proc_entry("dasd", NULL);
353 }
354