xref: /linux/drivers/s390/block/dasd_proc.c (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
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 #include <linux/ctype.h>
15 #include <linux/seq_file.h>
16 #include <linux/vmalloc.h>
17 #include <linux/proc_fs.h>
18 
19 #include <asm/debug.h>
20 #include <asm/uaccess.h>
21 
22 /* This is ugly... */
23 #define PRINTK_HEADER "dasd_proc:"
24 
25 #include "dasd_int.h"
26 
27 static struct proc_dir_entry *dasd_proc_root_entry = NULL;
28 static struct proc_dir_entry *dasd_devices_entry = NULL;
29 static struct proc_dir_entry *dasd_statistics_entry = NULL;
30 
31 static char *
32 dasd_get_user_string(const char __user *user_buf, size_t user_len)
33 {
34 	char *buffer;
35 
36 	buffer = kmalloc(user_len + 1, GFP_KERNEL);
37 	if (buffer == NULL)
38 		return ERR_PTR(-ENOMEM);
39 	if (copy_from_user(buffer, user_buf, user_len) != 0) {
40 		kfree(buffer);
41 		return ERR_PTR(-EFAULT);
42 	}
43 	/* got the string, now strip linefeed. */
44 	if (buffer[user_len - 1] == '\n')
45 		buffer[user_len - 1] = 0;
46 	else
47 		buffer[user_len] = 0;
48 	return buffer;
49 }
50 
51 static int
52 dasd_devices_show(struct seq_file *m, void *v)
53 {
54 	struct dasd_device *device;
55 	char *substr;
56 
57 	device = dasd_device_from_devindex((unsigned long) v - 1);
58 	if (IS_ERR(device))
59 		return 0;
60 	/* Print device number. */
61 	seq_printf(m, "%s", device->cdev->dev.bus_id);
62 	/* Print discipline string. */
63 	if (device != NULL && device->discipline != NULL)
64 		seq_printf(m, "(%s)", device->discipline->name);
65 	else
66 		seq_printf(m, "(none)");
67 	/* Print kdev. */
68 	if (device->gdp)
69 		seq_printf(m, " at (%3d:%6d)",
70 			   device->gdp->major, device->gdp->first_minor);
71 	else
72 		seq_printf(m, "  at (???:??????)");
73 	/* Print device name. */
74 	if (device->gdp)
75 		seq_printf(m, " is %-8s", device->gdp->disk_name);
76 	else
77 		seq_printf(m, " is ????????");
78 	/* Print devices features. */
79 	substr = (device->features & DASD_FEATURE_READONLY) ? "(ro)" : " ";
80 	seq_printf(m, "%4s: ", substr);
81 	/* Print device status information. */
82 	switch ((device != NULL) ? device->state : -1) {
83 	case -1:
84 		seq_printf(m, "unknown");
85 		break;
86 	case DASD_STATE_NEW:
87 		seq_printf(m, "new");
88 		break;
89 	case DASD_STATE_KNOWN:
90 		seq_printf(m, "detected");
91 		break;
92 	case DASD_STATE_BASIC:
93 		seq_printf(m, "basic");
94 		break;
95 	case DASD_STATE_UNFMT:
96 		seq_printf(m, "unformatted");
97 		break;
98 	case DASD_STATE_READY:
99 	case DASD_STATE_ONLINE:
100 		seq_printf(m, "active ");
101 		if (dasd_check_blocksize(device->bp_block))
102 			seq_printf(m, "n/f	 ");
103 		else
104 			seq_printf(m,
105 				   "at blocksize: %d, %ld blocks, %ld MB",
106 				   device->bp_block, device->blocks,
107 				   ((device->bp_block >> 9) *
108 				    device->blocks) >> 11);
109 		break;
110 	default:
111 		seq_printf(m, "no stat");
112 		break;
113 	}
114 	dasd_put_device(device);
115 	if (dasd_probeonly)
116 		seq_printf(m, "(probeonly)");
117 	seq_printf(m, "\n");
118 	return 0;
119 }
120 
121 static void *dasd_devices_start(struct seq_file *m, loff_t *pos)
122 {
123 	if (*pos >= dasd_max_devindex)
124 		return NULL;
125 	return (void *)((unsigned long) *pos + 1);
126 }
127 
128 static void *dasd_devices_next(struct seq_file *m, void *v, loff_t *pos)
129 {
130 	++*pos;
131 	return dasd_devices_start(m, pos);
132 }
133 
134 static void dasd_devices_stop(struct seq_file *m, void *v)
135 {
136 }
137 
138 static struct seq_operations dasd_devices_seq_ops = {
139 	.start		= dasd_devices_start,
140 	.next		= dasd_devices_next,
141 	.stop		= dasd_devices_stop,
142 	.show		= dasd_devices_show,
143 };
144 
145 static int dasd_devices_open(struct inode *inode, struct file *file)
146 {
147 	return seq_open(file, &dasd_devices_seq_ops);
148 }
149 
150 static const struct file_operations dasd_devices_file_ops = {
151 	.open		= dasd_devices_open,
152 	.read		= seq_read,
153 	.llseek		= seq_lseek,
154 	.release	= seq_release,
155 };
156 
157 static int
158 dasd_calc_metrics(char *page, char **start, off_t off,
159 		  int count, int *eof, int len)
160 {
161 	len = (len > off) ? len - off : 0;
162 	if (len > count)
163 		len = count;
164 	if (len < count)
165 		*eof = 1;
166 	*start = page + off;
167 	return len;
168 }
169 
170 static char *
171 dasd_statistics_array(char *str, unsigned int *array, int shift)
172 {
173 	int i;
174 
175 	for (i = 0; i < 32; i++) {
176 		str += sprintf(str, "%7d ", array[i] >> shift);
177 		if (i == 15)
178 			str += sprintf(str, "\n");
179 	}
180 	str += sprintf(str,"\n");
181 	return str;
182 }
183 
184 static int
185 dasd_statistics_read(char *page, char **start, off_t off,
186 		     int count, int *eof, void *data)
187 {
188 	unsigned long len;
189 #ifdef CONFIG_DASD_PROFILE
190 	struct dasd_profile_info_t *prof;
191 	char *str;
192 	int shift;
193 
194 	/* check for active profiling */
195 	if (dasd_profile_level == DASD_PROFILE_OFF) {
196 		len = sprintf(page, "Statistics are off - they might be "
197 				    "switched on using 'echo set on > "
198 				    "/proc/dasd/statistics'\n");
199 		return dasd_calc_metrics(page, start, off, count, eof, len);
200 	}
201 
202 	prof = &dasd_global_profile;
203 	/* prevent couter 'overflow' on output */
204 	for (shift = 0; (prof->dasd_io_reqs >> shift) > 9999999; shift++);
205 
206 	str = page;
207 	str += sprintf(str, "%d dasd I/O requests\n", prof->dasd_io_reqs);
208 	str += sprintf(str, "with %d sectors(512B each)\n",
209 		       prof->dasd_io_sects);
210 	str += sprintf(str,
211 		       "   __<4	   ___8	   __16	   __32	   __64	   _128	"
212 		       "   _256	   _512	   __1k	   __2k	   __4k	   __8k	"
213 		       "   _16k	   _32k	   _64k	   128k\n");
214 	str += sprintf(str,
215 		       "   _256	   _512	   __1M	   __2M	   __4M	   __8M	"
216 		       "   _16M	   _32M	   _64M	   128M	   256M	   512M	"
217 		       "   __1G	   __2G	   __4G " "   _>4G\n");
218 
219 	str += sprintf(str, "Histogram of sizes (512B secs)\n");
220 	str = dasd_statistics_array(str, prof->dasd_io_secs, shift);
221 	str += sprintf(str, "Histogram of I/O times (microseconds)\n");
222 	str = dasd_statistics_array(str, prof->dasd_io_times, shift);
223 	str += sprintf(str, "Histogram of I/O times per sector\n");
224 	str = dasd_statistics_array(str, prof->dasd_io_timps, shift);
225 	str += sprintf(str, "Histogram of I/O time till ssch\n");
226 	str = dasd_statistics_array(str, prof->dasd_io_time1, shift);
227 	str += sprintf(str, "Histogram of I/O time between ssch and irq\n");
228 	str = dasd_statistics_array(str, prof->dasd_io_time2, shift);
229 	str += sprintf(str, "Histogram of I/O time between ssch "
230 			    "and irq per sector\n");
231 	str = dasd_statistics_array(str, prof->dasd_io_time2ps, shift);
232 	str += sprintf(str, "Histogram of I/O time between irq and end\n");
233 	str = dasd_statistics_array(str, prof->dasd_io_time3, shift);
234 	str += sprintf(str, "# of req in chanq at enqueuing (1..32) \n");
235 	str = dasd_statistics_array(str, prof->dasd_io_nr_req, shift);
236 	len = str - page;
237 #else
238 	len = sprintf(page, "Statistics are not activated in this kernel\n");
239 #endif
240 	return dasd_calc_metrics(page, start, off, count, eof, len);
241 }
242 
243 static int
244 dasd_statistics_write(struct file *file, const char __user *user_buf,
245 		      unsigned long user_len, void *data)
246 {
247 #ifdef CONFIG_DASD_PROFILE
248 	char *buffer, *str;
249 
250 	if (user_len > 65536)
251 		user_len = 65536;
252 	buffer = dasd_get_user_string(user_buf, user_len);
253 	if (IS_ERR(buffer))
254 		return PTR_ERR(buffer);
255 	MESSAGE_LOG(KERN_INFO, "/proc/dasd/statictics: '%s'", buffer);
256 
257 	/* check for valid verbs */
258 	for (str = buffer; isspace(*str); str++);
259 	if (strncmp(str, "set", 3) == 0 && isspace(str[3])) {
260 		/* 'set xxx' was given */
261 		for (str = str + 4; isspace(*str); str++);
262 		if (strcmp(str, "on") == 0) {
263 			/* switch on statistics profiling */
264 			dasd_profile_level = DASD_PROFILE_ON;
265 			MESSAGE(KERN_INFO, "%s", "Statistics switched on");
266 		} else if (strcmp(str, "off") == 0) {
267 			/* switch off and reset statistics profiling */
268 			memset(&dasd_global_profile,
269 			       0, sizeof (struct dasd_profile_info_t));
270 			dasd_profile_level = DASD_PROFILE_OFF;
271 			MESSAGE(KERN_INFO, "%s", "Statistics switched off");
272 		} else
273 			goto out_error;
274 	} else if (strncmp(str, "reset", 5) == 0) {
275 		/* reset the statistics */
276 		memset(&dasd_global_profile, 0,
277 		       sizeof (struct dasd_profile_info_t));
278 		MESSAGE(KERN_INFO, "%s", "Statistics reset");
279 	} else
280 		goto out_error;
281 	kfree(buffer);
282 	return user_len;
283 out_error:
284 	MESSAGE(KERN_WARNING, "%s",
285 		"/proc/dasd/statistics: only 'set on', 'set off' "
286 		"and 'reset' are supported verbs");
287 	kfree(buffer);
288 	return -EINVAL;
289 #else
290 	MESSAGE(KERN_WARNING, "%s",
291 		"/proc/dasd/statistics: is not activated in this kernel");
292 	return user_len;
293 #endif				/* CONFIG_DASD_PROFILE */
294 }
295 
296 /*
297  * Create dasd proc-fs entries.
298  * In case creation failed, cleanup and return -ENOENT.
299  */
300 int
301 dasd_proc_init(void)
302 {
303 	dasd_proc_root_entry = proc_mkdir("dasd", &proc_root);
304 	if (!dasd_proc_root_entry)
305 		goto out_nodasd;
306 	dasd_proc_root_entry->owner = THIS_MODULE;
307 	dasd_devices_entry = create_proc_entry("devices",
308 					       S_IFREG | S_IRUGO | S_IWUSR,
309 					       dasd_proc_root_entry);
310 	if (!dasd_devices_entry)
311 		goto out_nodevices;
312 	dasd_devices_entry->proc_fops = &dasd_devices_file_ops;
313 	dasd_devices_entry->owner = THIS_MODULE;
314 	dasd_statistics_entry = create_proc_entry("statistics",
315 						  S_IFREG | S_IRUGO | S_IWUSR,
316 						  dasd_proc_root_entry);
317 	if (!dasd_statistics_entry)
318 		goto out_nostatistics;
319 	dasd_statistics_entry->read_proc = dasd_statistics_read;
320 	dasd_statistics_entry->write_proc = dasd_statistics_write;
321 	dasd_statistics_entry->owner = THIS_MODULE;
322 	return 0;
323 
324  out_nostatistics:
325 	remove_proc_entry("devices", dasd_proc_root_entry);
326  out_nodevices:
327 	remove_proc_entry("dasd", &proc_root);
328  out_nodasd:
329 	return -ENOENT;
330 }
331 
332 void
333 dasd_proc_exit(void)
334 {
335 	remove_proc_entry("devices", dasd_proc_root_entry);
336 	remove_proc_entry("statistics", dasd_proc_root_entry);
337 	remove_proc_entry("dasd", &proc_root);
338 }
339