xref: /linux/drivers/s390/block/dasd_proc.c (revision 776cfebb430c7b22c208b1b17add97f354d97cab)
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  * $Revision: 1.31 $
13  */
14 
15 #include <linux/config.h>
16 #include <linux/ctype.h>
17 #include <linux/seq_file.h>
18 #include <linux/vmalloc.h>
19 
20 #include <asm/debug.h>
21 #include <asm/uaccess.h>
22 
23 /* This is ugly... */
24 #define PRINTK_HEADER "dasd_proc:"
25 
26 #include "dasd_int.h"
27 
28 static struct proc_dir_entry *dasd_proc_root_entry = NULL;
29 static struct proc_dir_entry *dasd_devices_entry = NULL;
30 static struct proc_dir_entry *dasd_statistics_entry = NULL;
31 
32 static inline char *
33 dasd_get_user_string(const char __user *user_buf, size_t user_len)
34 {
35 	char *buffer;
36 
37 	buffer = kmalloc(user_len + 1, GFP_KERNEL);
38 	if (buffer == NULL)
39 		return ERR_PTR(-ENOMEM);
40 	if (copy_from_user(buffer, user_buf, user_len) != 0) {
41 		kfree(buffer);
42 		return ERR_PTR(-EFAULT);
43 	}
44 	/* got the string, now strip linefeed. */
45 	if (buffer[user_len - 1] == '\n')
46 		buffer[user_len - 1] = 0;
47 	else
48 		buffer[user_len] = 0;
49 	return buffer;
50 }
51 
52 static int
53 dasd_devices_show(struct seq_file *m, void *v)
54 {
55 	struct dasd_device *device;
56 	char *substr;
57 	int feature;
58 
59 	device = dasd_device_from_devindex((unsigned long) v - 1);
60 	if (IS_ERR(device))
61 		return 0;
62 	/* Print device number. */
63 	seq_printf(m, "%s", device->cdev->dev.bus_id);
64 	/* Print discipline string. */
65 	if (device != NULL && device->discipline != NULL)
66 		seq_printf(m, "(%s)", device->discipline->name);
67 	else
68 		seq_printf(m, "(none)");
69 	/* Print kdev. */
70 	if (device->gdp)
71 		seq_printf(m, " at (%3d:%6d)",
72 			   device->gdp->major, device->gdp->first_minor);
73 	else
74 		seq_printf(m, "  at (???:??????)");
75 	/* Print device name. */
76 	if (device->gdp)
77 		seq_printf(m, " is %-8s", device->gdp->disk_name);
78 	else
79 		seq_printf(m, " is ????????");
80 	/* Print devices features. */
81 	feature = dasd_get_feature(device->cdev, DASD_FEATURE_READONLY);
82 	if (feature < 0)
83 		return 0;
84 	substr = feature ? "(ro)" : " ";
85 	seq_printf(m, "%4s: ", substr);
86 	/* Print device status information. */
87 	switch ((device != NULL) ? device->state : -1) {
88 	case -1:
89 		seq_printf(m, "unknown");
90 		break;
91 	case DASD_STATE_NEW:
92 		seq_printf(m, "new");
93 		break;
94 	case DASD_STATE_KNOWN:
95 		seq_printf(m, "detected");
96 		break;
97 	case DASD_STATE_BASIC:
98 		seq_printf(m, "basic");
99 		break;
100 	case DASD_STATE_READY:
101 	case DASD_STATE_ONLINE:
102 		seq_printf(m, "active ");
103 		if (dasd_check_blocksize(device->bp_block))
104 			seq_printf(m, "n/f	 ");
105 		else
106 			seq_printf(m,
107 				   "at blocksize: %d, %ld blocks, %ld MB",
108 				   device->bp_block, device->blocks,
109 				   ((device->bp_block >> 9) *
110 				    device->blocks) >> 11);
111 		break;
112 	default:
113 		seq_printf(m, "no stat");
114 		break;
115 	}
116 	dasd_put_device(device);
117 	if (dasd_probeonly)
118 		seq_printf(m, "(probeonly)");
119 	seq_printf(m, "\n");
120 	return 0;
121 }
122 
123 static void *dasd_devices_start(struct seq_file *m, loff_t *pos)
124 {
125 	if (*pos >= dasd_max_devindex)
126 		return NULL;
127 	return (void *)((unsigned long) *pos + 1);
128 }
129 
130 static void *dasd_devices_next(struct seq_file *m, void *v, loff_t *pos)
131 {
132 	++*pos;
133 	return dasd_devices_start(m, pos);
134 }
135 
136 static void dasd_devices_stop(struct seq_file *m, void *v)
137 {
138 }
139 
140 static struct seq_operations dasd_devices_seq_ops = {
141 	.start		= dasd_devices_start,
142 	.next		= dasd_devices_next,
143 	.stop		= dasd_devices_stop,
144 	.show		= dasd_devices_show,
145 };
146 
147 static int dasd_devices_open(struct inode *inode, struct file *file)
148 {
149 	return seq_open(file, &dasd_devices_seq_ops);
150 }
151 
152 static struct file_operations dasd_devices_file_ops = {
153 	.open		= dasd_devices_open,
154 	.read		= seq_read,
155 	.llseek		= seq_lseek,
156 	.release	= seq_release,
157 };
158 
159 static inline int
160 dasd_calc_metrics(char *page, char **start, off_t off,
161 		  int count, int *eof, int len)
162 {
163 	len = (len > off) ? len - off : 0;
164 	if (len > count)
165 		len = count;
166 	if (len < count)
167 		*eof = 1;
168 	*start = page + off;
169 	return len;
170 }
171 
172 static inline char *
173 dasd_statistics_array(char *str, int *array, int shift)
174 {
175 	int i;
176 
177 	for (i = 0; i < 32; i++) {
178 		str += sprintf(str, "%7d ", array[i] >> shift);
179 		if (i == 15)
180 			str += sprintf(str, "\n");
181 	}
182 	str += sprintf(str,"\n");
183 	return str;
184 }
185 
186 static int
187 dasd_statistics_read(char *page, char **start, off_t off,
188 		     int count, int *eof, void *data)
189 {
190 	unsigned long len;
191 #ifdef CONFIG_DASD_PROFILE
192 	struct dasd_profile_info_t *prof;
193 	char *str;
194 	int shift;
195 
196 	/* check for active profiling */
197 	if (dasd_profile_level == DASD_PROFILE_OFF) {
198 		len = sprintf(page, "Statistics are off - they might be "
199 				    "switched on using 'echo set on > "
200 				    "/proc/dasd/statistics'\n");
201 		return dasd_calc_metrics(page, start, off, count, eof, len);
202 	}
203 
204 	prof = &dasd_global_profile;
205 	/* prevent couter 'overflow' on output */
206 	for (shift = 0; (prof->dasd_io_reqs >> shift) > 9999999; shift++);
207 
208 	str = page;
209 	str += sprintf(str, "%d dasd I/O requests\n", prof->dasd_io_reqs);
210 	str += sprintf(str, "with %d sectors(512B each)\n",
211 		       prof->dasd_io_sects);
212 	str += sprintf(str,
213 		       "   __<4	   ___8	   __16	   __32	   __64	   _128	"
214 		       "   _256	   _512	   __1k	   __2k	   __4k	   __8k	"
215 		       "   _16k	   _32k	   _64k	   128k\n");
216 	str += sprintf(str,
217 		       "   _256	   _512	   __1M	   __2M	   __4M	   __8M	"
218 		       "   _16M	   _32M	   _64M	   128M	   256M	   512M	"
219 		       "   __1G	   __2G	   __4G " "   _>4G\n");
220 
221 	str += sprintf(str, "Histogram of sizes (512B secs)\n");
222 	str = dasd_statistics_array(str, prof->dasd_io_secs, shift);
223 	str += sprintf(str, "Histogram of I/O times (microseconds)\n");
224 	str = dasd_statistics_array(str, prof->dasd_io_times, shift);
225 	str += sprintf(str, "Histogram of I/O times per sector\n");
226 	str = dasd_statistics_array(str, prof->dasd_io_timps, shift);
227 	str += sprintf(str, "Histogram of I/O time till ssch\n");
228 	str = dasd_statistics_array(str, prof->dasd_io_time1, shift);
229 	str += sprintf(str, "Histogram of I/O time between ssch and irq\n");
230 	str = dasd_statistics_array(str, prof->dasd_io_time2, shift);
231 	str += sprintf(str, "Histogram of I/O time between ssch "
232 			    "and irq per sector\n");
233 	str = dasd_statistics_array(str, prof->dasd_io_time2ps, shift);
234 	str += sprintf(str, "Histogram of I/O time between irq and end\n");
235 	str = dasd_statistics_array(str, prof->dasd_io_time3, shift);
236 	str += sprintf(str, "# of req in chanq at enqueuing (1..32) \n");
237 	str = dasd_statistics_array(str, prof->dasd_io_nr_req, shift);
238 	len = str - page;
239 #else
240 	len = sprintf(page, "Statistics are not activated in this kernel\n");
241 #endif
242 	return dasd_calc_metrics(page, start, off, count, eof, len);
243 }
244 
245 static int
246 dasd_statistics_write(struct file *file, const char __user *user_buf,
247 		      unsigned long user_len, void *data)
248 {
249 #ifdef CONFIG_DASD_PROFILE
250 	char *buffer, *str;
251 
252 	if (user_len > 65536)
253 		user_len = 65536;
254 	buffer = dasd_get_user_string(user_buf, user_len);
255 	if (IS_ERR(buffer))
256 		return PTR_ERR(buffer);
257 	MESSAGE_LOG(KERN_INFO, "/proc/dasd/statictics: '%s'", buffer);
258 
259 	/* check for valid verbs */
260 	for (str = buffer; isspace(*str); str++);
261 	if (strncmp(str, "set", 3) == 0 && isspace(str[3])) {
262 		/* 'set xxx' was given */
263 		for (str = str + 4; isspace(*str); str++);
264 		if (strcmp(str, "on") == 0) {
265 			/* switch on statistics profiling */
266 			dasd_profile_level = DASD_PROFILE_ON;
267 			MESSAGE(KERN_INFO, "%s", "Statistics switched on");
268 		} else if (strcmp(str, "off") == 0) {
269 			/* switch off and reset statistics profiling */
270 			memset(&dasd_global_profile,
271 			       0, sizeof (struct dasd_profile_info_t));
272 			dasd_profile_level = DASD_PROFILE_OFF;
273 			MESSAGE(KERN_INFO, "%s", "Statistics switched off");
274 		} else
275 			goto out_error;
276 	} else if (strncmp(str, "reset", 5) == 0) {
277 		/* reset the statistics */
278 		memset(&dasd_global_profile, 0,
279 		       sizeof (struct dasd_profile_info_t));
280 		MESSAGE(KERN_INFO, "%s", "Statistics reset");
281 	} else
282 		goto out_error;
283 	kfree(buffer);
284 	return user_len;
285 out_error:
286 	MESSAGE(KERN_WARNING, "%s",
287 		"/proc/dasd/statistics: only 'set on', 'set off' "
288 		"and 'reset' are supported verbs");
289 	kfree(buffer);
290 	return -EINVAL;
291 #else
292 	MESSAGE(KERN_WARNING, "%s",
293 		"/proc/dasd/statistics: is not activated in this kernel");
294 	return user_len;
295 #endif				/* CONFIG_DASD_PROFILE */
296 }
297 
298 int
299 dasd_proc_init(void)
300 {
301 	dasd_proc_root_entry = proc_mkdir("dasd", &proc_root);
302 	dasd_proc_root_entry->owner = THIS_MODULE;
303 	dasd_devices_entry = create_proc_entry("devices",
304 					       S_IFREG | S_IRUGO | S_IWUSR,
305 					       dasd_proc_root_entry);
306 	dasd_devices_entry->proc_fops = &dasd_devices_file_ops;
307 	dasd_devices_entry->owner = THIS_MODULE;
308 	dasd_statistics_entry = create_proc_entry("statistics",
309 						  S_IFREG | S_IRUGO | S_IWUSR,
310 						  dasd_proc_root_entry);
311 	dasd_statistics_entry->read_proc = dasd_statistics_read;
312 	dasd_statistics_entry->write_proc = dasd_statistics_write;
313 	dasd_statistics_entry->owner = THIS_MODULE;
314 	return 0;
315 }
316 
317 void
318 dasd_proc_exit(void)
319 {
320 	remove_proc_entry("devices", dasd_proc_root_entry);
321 	remove_proc_entry("statistics", dasd_proc_root_entry);
322 	remove_proc_entry("dasd", &proc_root);
323 }
324