xref: /linux/drivers/s390/block/dasd_proc.c (revision 8b1935e6a36b0967efc593d67ed3aebbfbc1f5b1)
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->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->state) {
96 	case DASD_STATE_NEW:
97 		seq_printf(m, "new");
98 		break;
99 	case DASD_STATE_KNOWN:
100 		seq_printf(m, "detected");
101 		break;
102 	case DASD_STATE_BASIC:
103 		seq_printf(m, "basic");
104 		break;
105 	case DASD_STATE_UNFMT:
106 		seq_printf(m, "unformatted");
107 		break;
108 	case DASD_STATE_READY:
109 	case DASD_STATE_ONLINE:
110 		seq_printf(m, "active ");
111 		if (dasd_check_blocksize(block->bp_block))
112 			seq_printf(m, "n/f	 ");
113 		else
114 			seq_printf(m,
115 				   "at blocksize: %d, %lld blocks, %lld MB",
116 				   block->bp_block, block->blocks,
117 				   ((block->bp_block >> 9) *
118 				    block->blocks) >> 11);
119 		break;
120 	default:
121 		seq_printf(m, "no stat");
122 		break;
123 	}
124 	dasd_put_device(device);
125 	if (dasd_probeonly)
126 		seq_printf(m, "(probeonly)");
127 	seq_printf(m, "\n");
128 	return 0;
129 }
130 
131 static void *dasd_devices_start(struct seq_file *m, loff_t *pos)
132 {
133 	if (*pos >= dasd_max_devindex)
134 		return NULL;
135 	return (void *)((unsigned long) *pos + 1);
136 }
137 
138 static void *dasd_devices_next(struct seq_file *m, void *v, loff_t *pos)
139 {
140 	++*pos;
141 	return dasd_devices_start(m, pos);
142 }
143 
144 static void dasd_devices_stop(struct seq_file *m, void *v)
145 {
146 }
147 
148 static const struct seq_operations dasd_devices_seq_ops = {
149 	.start		= dasd_devices_start,
150 	.next		= dasd_devices_next,
151 	.stop		= dasd_devices_stop,
152 	.show		= dasd_devices_show,
153 };
154 
155 static int dasd_devices_open(struct inode *inode, struct file *file)
156 {
157 	return seq_open(file, &dasd_devices_seq_ops);
158 }
159 
160 static const struct file_operations dasd_devices_file_ops = {
161 	.owner		= THIS_MODULE,
162 	.open		= dasd_devices_open,
163 	.read		= seq_read,
164 	.llseek		= seq_lseek,
165 	.release	= seq_release,
166 };
167 
168 #ifdef CONFIG_DASD_PROFILE
169 static void dasd_statistics_array(struct seq_file *m, unsigned int *array, int factor)
170 {
171 	int i;
172 
173 	for (i = 0; i < 32; i++) {
174 		seq_printf(m, "%7d ", array[i] / factor);
175 		if (i == 15)
176 			seq_putc(m, '\n');
177 	}
178 	seq_putc(m, '\n');
179 }
180 #endif /* CONFIG_DASD_PROFILE */
181 
182 static int dasd_stats_proc_show(struct seq_file *m, void *v)
183 {
184 #ifdef CONFIG_DASD_PROFILE
185 	struct dasd_profile_info_t *prof;
186 	int factor;
187 
188 	/* check for active profiling */
189 	if (dasd_profile_level == DASD_PROFILE_OFF) {
190 		seq_printf(m, "Statistics are off - they might be "
191 				    "switched on using 'echo set on > "
192 				    "/proc/dasd/statistics'\n");
193 		return 0;
194 	}
195 
196 	prof = &dasd_global_profile;
197 	/* prevent counter 'overflow' on output */
198 	for (factor = 1; (prof->dasd_io_reqs / factor) > 9999999;
199 	     factor *= 10);
200 
201 	seq_printf(m, "%d dasd I/O requests\n", prof->dasd_io_reqs);
202 	seq_printf(m, "with %u sectors(512B each)\n",
203 		       prof->dasd_io_sects);
204 	seq_printf(m, "Scale Factor is  %d\n", factor);
205 	seq_printf(m,
206 		       "   __<4	   ___8	   __16	   __32	   __64	   _128	"
207 		       "   _256	   _512	   __1k	   __2k	   __4k	   __8k	"
208 		       "   _16k	   _32k	   _64k	   128k\n");
209 	seq_printf(m,
210 		       "   _256	   _512	   __1M	   __2M	   __4M	   __8M	"
211 		       "   _16M	   _32M	   _64M	   128M	   256M	   512M	"
212 		       "   __1G	   __2G	   __4G " "   _>4G\n");
213 
214 	seq_printf(m, "Histogram of sizes (512B secs)\n");
215 	dasd_statistics_array(m, prof->dasd_io_secs, factor);
216 	seq_printf(m, "Histogram of I/O times (microseconds)\n");
217 	dasd_statistics_array(m, prof->dasd_io_times, factor);
218 	seq_printf(m, "Histogram of I/O times per sector\n");
219 	dasd_statistics_array(m, prof->dasd_io_timps, factor);
220 	seq_printf(m, "Histogram of I/O time till ssch\n");
221 	dasd_statistics_array(m, prof->dasd_io_time1, factor);
222 	seq_printf(m, "Histogram of I/O time between ssch and irq\n");
223 	dasd_statistics_array(m, prof->dasd_io_time2, factor);
224 	seq_printf(m, "Histogram of I/O time between ssch "
225 			    "and irq per sector\n");
226 	dasd_statistics_array(m, prof->dasd_io_time2ps, factor);
227 	seq_printf(m, "Histogram of I/O time between irq and end\n");
228 	dasd_statistics_array(m, prof->dasd_io_time3, factor);
229 	seq_printf(m, "# of req in chanq at enqueuing (1..32) \n");
230 	dasd_statistics_array(m, prof->dasd_io_nr_req, factor);
231 #else
232 	seq_printf(m, "Statistics are not activated in this kernel\n");
233 #endif
234 	return 0;
235 }
236 
237 static int dasd_stats_proc_open(struct inode *inode, struct file *file)
238 {
239 	return single_open(file, dasd_stats_proc_show, NULL);
240 }
241 
242 static ssize_t dasd_stats_proc_write(struct file *file,
243 		const char __user *user_buf, size_t user_len, loff_t *pos)
244 {
245 #ifdef CONFIG_DASD_PROFILE
246 	char *buffer, *str;
247 
248 	if (user_len > 65536)
249 		user_len = 65536;
250 	buffer = dasd_get_user_string(user_buf, user_len);
251 	if (IS_ERR(buffer))
252 		return PTR_ERR(buffer);
253 	DBF_EVENT(DBF_DEBUG, "/proc/dasd/statictics: '%s'\n", buffer);
254 
255 	/* check for valid verbs */
256 	str = skip_spaces(buffer);
257 	if (strncmp(str, "set", 3) == 0 && isspace(str[3])) {
258 		/* 'set xxx' was given */
259 		str = skip_spaces(str + 4);
260 		if (strcmp(str, "on") == 0) {
261 			/* switch on statistics profiling */
262 			dasd_profile_level = DASD_PROFILE_ON;
263 			pr_info("The statistics feature has been switched "
264 				"on\n");
265 		} else if (strcmp(str, "off") == 0) {
266 			/* switch off and reset statistics profiling */
267 			memset(&dasd_global_profile,
268 			       0, sizeof (struct dasd_profile_info_t));
269 			dasd_profile_level = DASD_PROFILE_OFF;
270 			pr_info("The statistics feature has been switched "
271 				"off\n");
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 		pr_info("The statistics have been reset\n");
279 	} else
280 		goto out_error;
281 	kfree(buffer);
282 	return user_len;
283 out_error:
284 	pr_warning("%s is not a supported value for /proc/dasd/statistics\n",
285 		str);
286 	kfree(buffer);
287 	return -EINVAL;
288 #else
289 	pr_warning("/proc/dasd/statistics: is not activated in this kernel\n");
290 	return user_len;
291 #endif				/* CONFIG_DASD_PROFILE */
292 }
293 
294 static const struct file_operations dasd_stats_proc_fops = {
295 	.owner		= THIS_MODULE,
296 	.open		= dasd_stats_proc_open,
297 	.read		= seq_read,
298 	.llseek		= seq_lseek,
299 	.release	= single_release,
300 	.write		= dasd_stats_proc_write,
301 };
302 
303 /*
304  * Create dasd proc-fs entries.
305  * In case creation failed, cleanup and return -ENOENT.
306  */
307 int
308 dasd_proc_init(void)
309 {
310 	dasd_proc_root_entry = proc_mkdir("dasd", NULL);
311 	if (!dasd_proc_root_entry)
312 		goto out_nodasd;
313 	dasd_devices_entry = proc_create("devices",
314 					 S_IFREG | S_IRUGO | S_IWUSR,
315 					 dasd_proc_root_entry,
316 					 &dasd_devices_file_ops);
317 	if (!dasd_devices_entry)
318 		goto out_nodevices;
319 	dasd_statistics_entry = proc_create("statistics",
320 					    S_IFREG | S_IRUGO | S_IWUSR,
321 					    dasd_proc_root_entry,
322 					    &dasd_stats_proc_fops);
323 	if (!dasd_statistics_entry)
324 		goto out_nostatistics;
325 	return 0;
326 
327  out_nostatistics:
328 	remove_proc_entry("devices", dasd_proc_root_entry);
329  out_nodevices:
330 	remove_proc_entry("dasd", NULL);
331  out_nodasd:
332 	return -ENOENT;
333 }
334 
335 void
336 dasd_proc_exit(void)
337 {
338 	remove_proc_entry("devices", dasd_proc_root_entry);
339 	remove_proc_entry("statistics", dasd_proc_root_entry);
340 	remove_proc_entry("dasd", NULL);
341 }
342