xref: /linux/drivers/s390/block/dasd_proc.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
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/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 <asm/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 #ifdef CONFIG_DASD_PROFILE
36 static char *
37 dasd_get_user_string(const char __user *user_buf, size_t user_len)
38 {
39 	char *buffer;
40 
41 	buffer = kmalloc(user_len + 1, GFP_KERNEL);
42 	if (buffer == NULL)
43 		return ERR_PTR(-ENOMEM);
44 	if (copy_from_user(buffer, user_buf, user_len) != 0) {
45 		kfree(buffer);
46 		return ERR_PTR(-EFAULT);
47 	}
48 	/* got the string, now strip linefeed. */
49 	if (buffer[user_len - 1] == '\n')
50 		buffer[user_len - 1] = 0;
51 	else
52 		buffer[user_len] = 0;
53 	return buffer;
54 }
55 #endif /* CONFIG_DASD_PROFILE */
56 
57 static int
58 dasd_devices_show(struct seq_file *m, void *v)
59 {
60 	struct dasd_device *device;
61 	struct dasd_block *block;
62 	char *substr;
63 
64 	device = dasd_device_from_devindex((unsigned long) v - 1);
65 	if (IS_ERR(device))
66 		return 0;
67 	if (device->block)
68 		block = device->block;
69 	else {
70 		dasd_put_device(device);
71 		return 0;
72 	}
73 	/* Print device number. */
74 	seq_printf(m, "%s", dev_name(&device->cdev->dev));
75 	/* Print discipline string. */
76 	if (device->discipline != NULL)
77 		seq_printf(m, "(%s)", device->discipline->name);
78 	else
79 		seq_printf(m, "(none)");
80 	/* Print kdev. */
81 	if (block->gdp)
82 		seq_printf(m, " at (%3d:%6d)",
83 			   MAJOR(disk_devt(block->gdp)),
84 			   MINOR(disk_devt(block->gdp)));
85 	else
86 		seq_printf(m, "  at (???:??????)");
87 	/* Print device name. */
88 	if (block->gdp)
89 		seq_printf(m, " is %-8s", block->gdp->disk_name);
90 	else
91 		seq_printf(m, " is ????????");
92 	/* Print devices features. */
93 	substr = (device->features & DASD_FEATURE_READONLY) ? "(ro)" : " ";
94 	seq_printf(m, "%4s: ", substr);
95 	/* Print device status information. */
96 	switch (device->state) {
97 	case DASD_STATE_NEW:
98 		seq_printf(m, "new");
99 		break;
100 	case DASD_STATE_KNOWN:
101 		seq_printf(m, "detected");
102 		break;
103 	case DASD_STATE_BASIC:
104 		seq_printf(m, "basic");
105 		break;
106 	case DASD_STATE_UNFMT:
107 		seq_printf(m, "unformatted");
108 		break;
109 	case DASD_STATE_READY:
110 	case DASD_STATE_ONLINE:
111 		seq_printf(m, "active ");
112 		if (dasd_check_blocksize(block->bp_block))
113 			seq_printf(m, "n/f	 ");
114 		else
115 			seq_printf(m,
116 				   "at blocksize: %d, %lld blocks, %lld MB",
117 				   block->bp_block, block->blocks,
118 				   ((block->bp_block >> 9) *
119 				    block->blocks) >> 11);
120 		break;
121 	default:
122 		seq_printf(m, "no stat");
123 		break;
124 	}
125 	dasd_put_device(device);
126 	if (dasd_probeonly)
127 		seq_printf(m, "(probeonly)");
128 	seq_printf(m, "\n");
129 	return 0;
130 }
131 
132 static void *dasd_devices_start(struct seq_file *m, loff_t *pos)
133 {
134 	if (*pos >= dasd_max_devindex)
135 		return NULL;
136 	return (void *)((unsigned long) *pos + 1);
137 }
138 
139 static void *dasd_devices_next(struct seq_file *m, void *v, loff_t *pos)
140 {
141 	++*pos;
142 	return dasd_devices_start(m, pos);
143 }
144 
145 static void dasd_devices_stop(struct seq_file *m, void *v)
146 {
147 }
148 
149 static const struct seq_operations dasd_devices_seq_ops = {
150 	.start		= dasd_devices_start,
151 	.next		= dasd_devices_next,
152 	.stop		= dasd_devices_stop,
153 	.show		= dasd_devices_show,
154 };
155 
156 static int dasd_devices_open(struct inode *inode, struct file *file)
157 {
158 	return seq_open(file, &dasd_devices_seq_ops);
159 }
160 
161 static const struct file_operations dasd_devices_file_ops = {
162 	.owner		= THIS_MODULE,
163 	.open		= dasd_devices_open,
164 	.read		= seq_read,
165 	.llseek		= seq_lseek,
166 	.release	= seq_release,
167 };
168 
169 #ifdef CONFIG_DASD_PROFILE
170 static void dasd_statistics_array(struct seq_file *m, unsigned int *array, int factor)
171 {
172 	int i;
173 
174 	for (i = 0; i < 32; i++) {
175 		seq_printf(m, "%7d ", array[i] / factor);
176 		if (i == 15)
177 			seq_putc(m, '\n');
178 	}
179 	seq_putc(m, '\n');
180 }
181 #endif /* CONFIG_DASD_PROFILE */
182 
183 static int dasd_stats_proc_show(struct seq_file *m, void *v)
184 {
185 #ifdef CONFIG_DASD_PROFILE
186 	struct dasd_profile_info_t *prof;
187 	int factor;
188 
189 	/* check for active profiling */
190 	if (dasd_profile_level == DASD_PROFILE_OFF) {
191 		seq_printf(m, "Statistics are off - they might be "
192 				    "switched on using 'echo set on > "
193 				    "/proc/dasd/statistics'\n");
194 		return 0;
195 	}
196 
197 	prof = &dasd_global_profile;
198 	/* prevent counter 'overflow' on output */
199 	for (factor = 1; (prof->dasd_io_reqs / factor) > 9999999;
200 	     factor *= 10);
201 
202 	seq_printf(m, "%d dasd I/O requests\n", prof->dasd_io_reqs);
203 	seq_printf(m, "with %u sectors(512B each)\n",
204 		       prof->dasd_io_sects);
205 	seq_printf(m, "Scale Factor is  %d\n", factor);
206 	seq_printf(m,
207 		       "   __<4	   ___8	   __16	   __32	   __64	   _128	"
208 		       "   _256	   _512	   __1k	   __2k	   __4k	   __8k	"
209 		       "   _16k	   _32k	   _64k	   128k\n");
210 	seq_printf(m,
211 		       "   _256	   _512	   __1M	   __2M	   __4M	   __8M	"
212 		       "   _16M	   _32M	   _64M	   128M	   256M	   512M	"
213 		       "   __1G	   __2G	   __4G " "   _>4G\n");
214 
215 	seq_printf(m, "Histogram of sizes (512B secs)\n");
216 	dasd_statistics_array(m, prof->dasd_io_secs, factor);
217 	seq_printf(m, "Histogram of I/O times (microseconds)\n");
218 	dasd_statistics_array(m, prof->dasd_io_times, factor);
219 	seq_printf(m, "Histogram of I/O times per sector\n");
220 	dasd_statistics_array(m, prof->dasd_io_timps, factor);
221 	seq_printf(m, "Histogram of I/O time till ssch\n");
222 	dasd_statistics_array(m, prof->dasd_io_time1, factor);
223 	seq_printf(m, "Histogram of I/O time between ssch and irq\n");
224 	dasd_statistics_array(m, prof->dasd_io_time2, factor);
225 	seq_printf(m, "Histogram of I/O time between ssch "
226 			    "and irq per sector\n");
227 	dasd_statistics_array(m, prof->dasd_io_time2ps, factor);
228 	seq_printf(m, "Histogram of I/O time between irq and end\n");
229 	dasd_statistics_array(m, prof->dasd_io_time3, factor);
230 	seq_printf(m, "# of req in chanq at enqueuing (1..32) \n");
231 	dasd_statistics_array(m, prof->dasd_io_nr_req, factor);
232 #else
233 	seq_printf(m, "Statistics are not activated in this kernel\n");
234 #endif
235 	return 0;
236 }
237 
238 static int dasd_stats_proc_open(struct inode *inode, struct file *file)
239 {
240 	return single_open(file, dasd_stats_proc_show, NULL);
241 }
242 
243 static ssize_t dasd_stats_proc_write(struct file *file,
244 		const char __user *user_buf, size_t user_len, loff_t *pos)
245 {
246 #ifdef CONFIG_DASD_PROFILE
247 	char *buffer, *str;
248 
249 	if (user_len > 65536)
250 		user_len = 65536;
251 	buffer = dasd_get_user_string(user_buf, user_len);
252 	if (IS_ERR(buffer))
253 		return PTR_ERR(buffer);
254 	DBF_EVENT(DBF_DEBUG, "/proc/dasd/statictics: '%s'\n", buffer);
255 
256 	/* check for valid verbs */
257 	str = skip_spaces(buffer);
258 	if (strncmp(str, "set", 3) == 0 && isspace(str[3])) {
259 		/* 'set xxx' was given */
260 		str = skip_spaces(str + 4);
261 		if (strcmp(str, "on") == 0) {
262 			/* switch on statistics profiling */
263 			dasd_profile_level = DASD_PROFILE_ON;
264 			pr_info("The statistics feature has been switched "
265 				"on\n");
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 			pr_info("The statistics feature has been switched "
272 				"off\n");
273 		} else
274 			goto out_error;
275 	} else if (strncmp(str, "reset", 5) == 0) {
276 		/* reset the statistics */
277 		memset(&dasd_global_profile, 0,
278 		       sizeof (struct dasd_profile_info_t));
279 		pr_info("The statistics have been reset\n");
280 	} else
281 		goto out_error;
282 	kfree(buffer);
283 	return user_len;
284 out_error:
285 	pr_warning("%s is not a supported value for /proc/dasd/statistics\n",
286 		str);
287 	kfree(buffer);
288 	return -EINVAL;
289 #else
290 	pr_warning("/proc/dasd/statistics: is not activated in this kernel\n");
291 	return user_len;
292 #endif				/* CONFIG_DASD_PROFILE */
293 }
294 
295 static const struct file_operations dasd_stats_proc_fops = {
296 	.owner		= THIS_MODULE,
297 	.open		= dasd_stats_proc_open,
298 	.read		= seq_read,
299 	.llseek		= seq_lseek,
300 	.release	= single_release,
301 	.write		= dasd_stats_proc_write,
302 };
303 
304 /*
305  * Create dasd proc-fs entries.
306  * In case creation failed, cleanup and return -ENOENT.
307  */
308 int
309 dasd_proc_init(void)
310 {
311 	dasd_proc_root_entry = proc_mkdir("dasd", NULL);
312 	if (!dasd_proc_root_entry)
313 		goto out_nodasd;
314 	dasd_devices_entry = proc_create("devices",
315 					 S_IFREG | S_IRUGO | S_IWUSR,
316 					 dasd_proc_root_entry,
317 					 &dasd_devices_file_ops);
318 	if (!dasd_devices_entry)
319 		goto out_nodevices;
320 	dasd_statistics_entry = proc_create("statistics",
321 					    S_IFREG | S_IRUGO | S_IWUSR,
322 					    dasd_proc_root_entry,
323 					    &dasd_stats_proc_fops);
324 	if (!dasd_statistics_entry)
325 		goto out_nostatistics;
326 	return 0;
327 
328  out_nostatistics:
329 	remove_proc_entry("devices", dasd_proc_root_entry);
330  out_nodevices:
331 	remove_proc_entry("dasd", NULL);
332  out_nodasd:
333 	return -ENOENT;
334 }
335 
336 void
337 dasd_proc_exit(void)
338 {
339 	remove_proc_entry("devices", dasd_proc_root_entry);
340 	remove_proc_entry("statistics", dasd_proc_root_entry);
341 	remove_proc_entry("dasd", NULL);
342 }
343