03c0e40a92ff9fafc20694ee0127822d03a4db4f
[safe/jmp/linux-2.6] / drivers / s390 / block / dasd_proc.c
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 #ifdef CONFIG_DASD_PROFILE
32 static 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 #endif /* CONFIG_DASD_PROFILE */
52
53 static int
54 dasd_devices_show(struct seq_file *m, void *v)
55 {
56         struct dasd_device *device;
57         struct dasd_block *block;
58         char *substr;
59
60         device = dasd_device_from_devindex((unsigned long) v - 1);
61         if (IS_ERR(device))
62                 return 0;
63         if (device->block)
64                 block = device->block;
65         else {
66                 dasd_put_device(device);
67                 return 0;
68         }
69         /* Print device number. */
70         seq_printf(m, "%s", device->cdev->dev.bus_id);
71         /* Print discipline string. */
72         if (device != NULL && device->discipline != NULL)
73                 seq_printf(m, "(%s)", device->discipline->name);
74         else
75                 seq_printf(m, "(none)");
76         /* Print kdev. */
77         if (block->gdp)
78                 seq_printf(m, " at (%3d:%6d)",
79                            block->gdp->major, block->gdp->first_minor);
80         else
81                 seq_printf(m, "  at (???:??????)");
82         /* Print device name. */
83         if (block->gdp)
84                 seq_printf(m, " is %-8s", block->gdp->disk_name);
85         else
86                 seq_printf(m, " is ????????");
87         /* Print devices features. */
88         substr = (device->features & DASD_FEATURE_READONLY) ? "(ro)" : " ";
89         seq_printf(m, "%4s: ", substr);
90         /* Print device status information. */
91         switch ((device != NULL) ? device->state : -1) {
92         case -1:
93                 seq_printf(m, "unknown");
94                 break;
95         case DASD_STATE_NEW:
96                 seq_printf(m, "new");
97                 break;
98         case DASD_STATE_KNOWN:
99                 seq_printf(m, "detected");
100                 break;
101         case DASD_STATE_BASIC:
102                 seq_printf(m, "basic");
103                 break;
104         case DASD_STATE_UNFMT:
105                 seq_printf(m, "unformatted");
106                 break;
107         case DASD_STATE_READY:
108         case DASD_STATE_ONLINE:
109                 seq_printf(m, "active ");
110                 if (dasd_check_blocksize(block->bp_block))
111                         seq_printf(m, "n/f       ");
112                 else
113                         seq_printf(m,
114                                    "at blocksize: %d, %ld blocks, %ld MB",
115                                    block->bp_block, block->blocks,
116                                    ((block->bp_block >> 9) *
117                                     block->blocks) >> 11);
118                 break;
119         default:
120                 seq_printf(m, "no stat");
121                 break;
122         }
123         dasd_put_device(device);
124         if (dasd_probeonly)
125                 seq_printf(m, "(probeonly)");
126         seq_printf(m, "\n");
127         return 0;
128 }
129
130 static void *dasd_devices_start(struct seq_file *m, loff_t *pos)
131 {
132         if (*pos >= dasd_max_devindex)
133                 return NULL;
134         return (void *)((unsigned long) *pos + 1);
135 }
136
137 static void *dasd_devices_next(struct seq_file *m, void *v, loff_t *pos)
138 {
139         ++*pos;
140         return dasd_devices_start(m, pos);
141 }
142
143 static void dasd_devices_stop(struct seq_file *m, void *v)
144 {
145 }
146
147 static const struct seq_operations dasd_devices_seq_ops = {
148         .start          = dasd_devices_start,
149         .next           = dasd_devices_next,
150         .stop           = dasd_devices_stop,
151         .show           = dasd_devices_show,
152 };
153
154 static int dasd_devices_open(struct inode *inode, struct file *file)
155 {
156         return seq_open(file, &dasd_devices_seq_ops);
157 }
158
159 static const struct file_operations dasd_devices_file_ops = {
160         .owner          = THIS_MODULE,
161         .open           = dasd_devices_open,
162         .read           = seq_read,
163         .llseek         = seq_lseek,
164         .release        = seq_release,
165 };
166
167 static int
168 dasd_calc_metrics(char *page, char **start, off_t off,
169                   int count, int *eof, int len)
170 {
171         len = (len > off) ? len - off : 0;
172         if (len > count)
173                 len = count;
174         if (len < count)
175                 *eof = 1;
176         *start = page + off;
177         return len;
178 }
179
180 #ifdef CONFIG_DASD_PROFILE
181 static char *
182 dasd_statistics_array(char *str, unsigned int *array, int shift)
183 {
184         int i;
185
186         for (i = 0; i < 32; i++) {
187                 str += sprintf(str, "%7d ", array[i] >> shift);
188                 if (i == 15)
189                         str += sprintf(str, "\n");
190         }
191         str += sprintf(str,"\n");
192         return str;
193 }
194 #endif /* CONFIG_DASD_PROFILE */
195
196 static int
197 dasd_statistics_read(char *page, char **start, off_t off,
198                      int count, int *eof, void *data)
199 {
200         unsigned long len;
201 #ifdef CONFIG_DASD_PROFILE
202         struct dasd_profile_info_t *prof;
203         char *str;
204         int shift;
205
206         /* check for active profiling */
207         if (dasd_profile_level == DASD_PROFILE_OFF) {
208                 len = sprintf(page, "Statistics are off - they might be "
209                                     "switched on using 'echo set on > "
210                                     "/proc/dasd/statistics'\n");
211                 return dasd_calc_metrics(page, start, off, count, eof, len);
212         }
213
214         prof = &dasd_global_profile;
215         /* prevent couter 'overflow' on output */
216         for (shift = 0; (prof->dasd_io_reqs >> shift) > 9999999; shift++);
217
218         str = page;
219         str += sprintf(str, "%d dasd I/O requests\n", prof->dasd_io_reqs);
220         str += sprintf(str, "with %d sectors(512B each)\n",
221                        prof->dasd_io_sects);
222         str += sprintf(str,
223                        "   __<4    ___8    __16    __32    __64    _128 "
224                        "   _256    _512    __1k    __2k    __4k    __8k "
225                        "   _16k    _32k    _64k    128k\n");
226         str += sprintf(str,
227                        "   _256    _512    __1M    __2M    __4M    __8M "
228                        "   _16M    _32M    _64M    128M    256M    512M "
229                        "   __1G    __2G    __4G " "   _>4G\n");
230
231         str += sprintf(str, "Histogram of sizes (512B secs)\n");
232         str = dasd_statistics_array(str, prof->dasd_io_secs, shift);
233         str += sprintf(str, "Histogram of I/O times (microseconds)\n");
234         str = dasd_statistics_array(str, prof->dasd_io_times, shift);
235         str += sprintf(str, "Histogram of I/O times per sector\n");
236         str = dasd_statistics_array(str, prof->dasd_io_timps, shift);
237         str += sprintf(str, "Histogram of I/O time till ssch\n");
238         str = dasd_statistics_array(str, prof->dasd_io_time1, shift);
239         str += sprintf(str, "Histogram of I/O time between ssch and irq\n");
240         str = dasd_statistics_array(str, prof->dasd_io_time2, shift);
241         str += sprintf(str, "Histogram of I/O time between ssch "
242                             "and irq per sector\n");
243         str = dasd_statistics_array(str, prof->dasd_io_time2ps, shift);
244         str += sprintf(str, "Histogram of I/O time between irq and end\n");
245         str = dasd_statistics_array(str, prof->dasd_io_time3, shift);
246         str += sprintf(str, "# of req in chanq at enqueuing (1..32) \n");
247         str = dasd_statistics_array(str, prof->dasd_io_nr_req, shift);
248         len = str - page;
249 #else
250         len = sprintf(page, "Statistics are not activated in this kernel\n");
251 #endif
252         return dasd_calc_metrics(page, start, off, count, eof, len);
253 }
254
255 static int
256 dasd_statistics_write(struct file *file, const char __user *user_buf,
257                       unsigned long user_len, void *data)
258 {
259 #ifdef CONFIG_DASD_PROFILE
260         char *buffer, *str;
261
262         if (user_len > 65536)
263                 user_len = 65536;
264         buffer = dasd_get_user_string(user_buf, user_len);
265         if (IS_ERR(buffer))
266                 return PTR_ERR(buffer);
267         MESSAGE_LOG(KERN_INFO, "/proc/dasd/statictics: '%s'", buffer);
268
269         /* check for valid verbs */
270         for (str = buffer; isspace(*str); str++);
271         if (strncmp(str, "set", 3) == 0 && isspace(str[3])) {
272                 /* 'set xxx' was given */
273                 for (str = str + 4; isspace(*str); str++);
274                 if (strcmp(str, "on") == 0) {
275                         /* switch on statistics profiling */
276                         dasd_profile_level = DASD_PROFILE_ON;
277                         MESSAGE(KERN_INFO, "%s", "Statistics switched on");
278                 } else if (strcmp(str, "off") == 0) {
279                         /* switch off and reset statistics profiling */
280                         memset(&dasd_global_profile,
281                                0, sizeof (struct dasd_profile_info_t));
282                         dasd_profile_level = DASD_PROFILE_OFF;
283                         MESSAGE(KERN_INFO, "%s", "Statistics switched off");
284                 } else
285                         goto out_error;
286         } else if (strncmp(str, "reset", 5) == 0) {
287                 /* reset the statistics */
288                 memset(&dasd_global_profile, 0,
289                        sizeof (struct dasd_profile_info_t));
290                 MESSAGE(KERN_INFO, "%s", "Statistics reset");
291         } else
292                 goto out_error;
293         kfree(buffer);
294         return user_len;
295 out_error:
296         MESSAGE(KERN_WARNING, "%s",
297                 "/proc/dasd/statistics: only 'set on', 'set off' "
298                 "and 'reset' are supported verbs");
299         kfree(buffer);
300         return -EINVAL;
301 #else
302         MESSAGE(KERN_WARNING, "%s",
303                 "/proc/dasd/statistics: is not activated in this kernel");
304         return user_len;
305 #endif                          /* CONFIG_DASD_PROFILE */
306 }
307
308 /*
309  * Create dasd proc-fs entries.
310  * In case creation failed, cleanup and return -ENOENT.
311  */
312 int
313 dasd_proc_init(void)
314 {
315         dasd_proc_root_entry = proc_mkdir("dasd", NULL);
316         if (!dasd_proc_root_entry)
317                 goto out_nodasd;
318         dasd_proc_root_entry->owner = THIS_MODULE;
319         dasd_devices_entry = proc_create("devices",
320                                          S_IFREG | S_IRUGO | S_IWUSR,
321                                          dasd_proc_root_entry,
322                                          &dasd_devices_file_ops);
323         if (!dasd_devices_entry)
324                 goto out_nodevices;
325         dasd_statistics_entry = create_proc_entry("statistics",
326                                                   S_IFREG | S_IRUGO | S_IWUSR,
327                                                   dasd_proc_root_entry);
328         if (!dasd_statistics_entry)
329                 goto out_nostatistics;
330         dasd_statistics_entry->read_proc = dasd_statistics_read;
331         dasd_statistics_entry->write_proc = dasd_statistics_write;
332         dasd_statistics_entry->owner = THIS_MODULE;
333         return 0;
334
335  out_nostatistics:
336         remove_proc_entry("devices", dasd_proc_root_entry);
337  out_nodevices:
338         remove_proc_entry("dasd", NULL);
339  out_nodasd:
340         return -ENOENT;
341 }
342
343 void
344 dasd_proc_exit(void)
345 {
346         remove_proc_entry("devices", dasd_proc_root_entry);
347         remove_proc_entry("statistics", dasd_proc_root_entry);
348         remove_proc_entry("dasd", NULL);
349 }