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