Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
[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 #define KMSG_COMPONENT "dasd"
15
16 #include <linux/ctype.h>
17 #include <linux/seq_file.h>
18 #include <linux/vmalloc.h>
19 #include <linux/proc_fs.h>
20
21 #include <asm/debug.h>
22 #include <asm/uaccess.h>
23
24 /* This is ugly... */
25 #define PRINTK_HEADER "dasd_proc:"
26
27 #include "dasd_int.h"
28
29 static struct proc_dir_entry *dasd_proc_root_entry = NULL;
30 static struct proc_dir_entry *dasd_devices_entry = NULL;
31 static struct proc_dir_entry *dasd_statistics_entry = NULL;
32
33 #ifdef CONFIG_DASD_PROFILE
34 static char *
35 dasd_get_user_string(const char __user *user_buf, size_t user_len)
36 {
37         char *buffer;
38
39         buffer = kmalloc(user_len + 1, GFP_KERNEL);
40         if (buffer == NULL)
41                 return ERR_PTR(-ENOMEM);
42         if (copy_from_user(buffer, user_buf, user_len) != 0) {
43                 kfree(buffer);
44                 return ERR_PTR(-EFAULT);
45         }
46         /* got the string, now strip linefeed. */
47         if (buffer[user_len - 1] == '\n')
48                 buffer[user_len - 1] = 0;
49         else
50                 buffer[user_len] = 0;
51         return buffer;
52 }
53 #endif /* CONFIG_DASD_PROFILE */
54
55 static int
56 dasd_devices_show(struct seq_file *m, void *v)
57 {
58         struct dasd_device *device;
59         struct dasd_block *block;
60         char *substr;
61
62         device = dasd_device_from_devindex((unsigned long) v - 1);
63         if (IS_ERR(device))
64                 return 0;
65         if (device->block)
66                 block = device->block;
67         else {
68                 dasd_put_device(device);
69                 return 0;
70         }
71         /* Print device number. */
72         seq_printf(m, "%s", dev_name(&device->cdev->dev));
73         /* Print discipline string. */
74         if (device != NULL && device->discipline != NULL)
75                 seq_printf(m, "(%s)", device->discipline->name);
76         else
77                 seq_printf(m, "(none)");
78         /* Print kdev. */
79         if (block->gdp)
80                 seq_printf(m, " at (%3d:%6d)",
81                            MAJOR(disk_devt(block->gdp)),
82                            MINOR(disk_devt(block->gdp)));
83         else
84                 seq_printf(m, "  at (???:??????)");
85         /* Print device name. */
86         if (block->gdp)
87                 seq_printf(m, " is %-8s", block->gdp->disk_name);
88         else
89                 seq_printf(m, " is ????????");
90         /* Print devices features. */
91         substr = (device->features & DASD_FEATURE_READONLY) ? "(ro)" : " ";
92         seq_printf(m, "%4s: ", substr);
93         /* Print device status information. */
94         switch ((device != NULL) ? device->state : -1) {
95         case -1:
96                 seq_printf(m, "unknown");
97                 break;
98         case DASD_STATE_NEW:
99                 seq_printf(m, "new");
100                 break;
101         case DASD_STATE_KNOWN:
102                 seq_printf(m, "detected");
103                 break;
104         case DASD_STATE_BASIC:
105                 seq_printf(m, "basic");
106                 break;
107         case DASD_STATE_UNFMT:
108                 seq_printf(m, "unformatted");
109                 break;
110         case DASD_STATE_READY:
111         case DASD_STATE_ONLINE:
112                 seq_printf(m, "active ");
113                 if (dasd_check_blocksize(block->bp_block))
114                         seq_printf(m, "n/f       ");
115                 else
116                         seq_printf(m,
117                                    "at blocksize: %d, %lld blocks, %lld MB",
118                                    block->bp_block, block->blocks,
119                                    ((block->bp_block >> 9) *
120                                     block->blocks) >> 11);
121                 break;
122         default:
123                 seq_printf(m, "no stat");
124                 break;
125         }
126         dasd_put_device(device);
127         if (dasd_probeonly)
128                 seq_printf(m, "(probeonly)");
129         seq_printf(m, "\n");
130         return 0;
131 }
132
133 static void *dasd_devices_start(struct seq_file *m, loff_t *pos)
134 {
135         if (*pos >= dasd_max_devindex)
136                 return NULL;
137         return (void *)((unsigned long) *pos + 1);
138 }
139
140 static void *dasd_devices_next(struct seq_file *m, void *v, loff_t *pos)
141 {
142         ++*pos;
143         return dasd_devices_start(m, pos);
144 }
145
146 static void dasd_devices_stop(struct seq_file *m, void *v)
147 {
148 }
149
150 static const struct seq_operations dasd_devices_seq_ops = {
151         .start          = dasd_devices_start,
152         .next           = dasd_devices_next,
153         .stop           = dasd_devices_stop,
154         .show           = dasd_devices_show,
155 };
156
157 static int dasd_devices_open(struct inode *inode, struct file *file)
158 {
159         return seq_open(file, &dasd_devices_seq_ops);
160 }
161
162 static const struct file_operations dasd_devices_file_ops = {
163         .owner          = THIS_MODULE,
164         .open           = dasd_devices_open,
165         .read           = seq_read,
166         .llseek         = seq_lseek,
167         .release        = seq_release,
168 };
169
170 static int
171 dasd_calc_metrics(char *page, char **start, off_t off,
172                   int count, int *eof, int len)
173 {
174         len = (len > off) ? len - off : 0;
175         if (len > count)
176                 len = count;
177         if (len < count)
178                 *eof = 1;
179         *start = page + off;
180         return len;
181 }
182
183 #ifdef CONFIG_DASD_PROFILE
184 static char *
185 dasd_statistics_array(char *str, unsigned int *array, int factor)
186 {
187         int i;
188
189         for (i = 0; i < 32; i++) {
190                 str += sprintf(str, "%7d ", array[i] / factor);
191                 if (i == 15)
192                         str += sprintf(str, "\n");
193         }
194         str += sprintf(str,"\n");
195         return str;
196 }
197 #endif /* CONFIG_DASD_PROFILE */
198
199 static int
200 dasd_statistics_read(char *page, char **start, off_t off,
201                      int count, int *eof, void *data)
202 {
203         unsigned long len;
204 #ifdef CONFIG_DASD_PROFILE
205         struct dasd_profile_info_t *prof;
206         char *str;
207         int factor;
208
209         /* check for active profiling */
210         if (dasd_profile_level == DASD_PROFILE_OFF) {
211                 len = sprintf(page, "Statistics are off - they might be "
212                                     "switched on using 'echo set on > "
213                                     "/proc/dasd/statistics'\n");
214                 return dasd_calc_metrics(page, start, off, count, eof, len);
215         }
216
217         prof = &dasd_global_profile;
218         /* prevent couter 'overflow' on output */
219         for (factor = 1; (prof->dasd_io_reqs / factor) > 9999999;
220              factor *= 10);
221
222         str = page;
223         str += sprintf(str, "%d dasd I/O requests\n", prof->dasd_io_reqs);
224         str += sprintf(str, "with %u sectors(512B each)\n",
225                        prof->dasd_io_sects);
226         str += sprintf(str, "Scale Factor is  %d\n", factor);
227         str += sprintf(str,
228                        "   __<4    ___8    __16    __32    __64    _128 "
229                        "   _256    _512    __1k    __2k    __4k    __8k "
230                        "   _16k    _32k    _64k    128k\n");
231         str += sprintf(str,
232                        "   _256    _512    __1M    __2M    __4M    __8M "
233                        "   _16M    _32M    _64M    128M    256M    512M "
234                        "   __1G    __2G    __4G " "   _>4G\n");
235
236         str += sprintf(str, "Histogram of sizes (512B secs)\n");
237         str = dasd_statistics_array(str, prof->dasd_io_secs, factor);
238         str += sprintf(str, "Histogram of I/O times (microseconds)\n");
239         str = dasd_statistics_array(str, prof->dasd_io_times, factor);
240         str += sprintf(str, "Histogram of I/O times per sector\n");
241         str = dasd_statistics_array(str, prof->dasd_io_timps, factor);
242         str += sprintf(str, "Histogram of I/O time till ssch\n");
243         str = dasd_statistics_array(str, prof->dasd_io_time1, factor);
244         str += sprintf(str, "Histogram of I/O time between ssch and irq\n");
245         str = dasd_statistics_array(str, prof->dasd_io_time2, factor);
246         str += sprintf(str, "Histogram of I/O time between ssch "
247                             "and irq per sector\n");
248         str = dasd_statistics_array(str, prof->dasd_io_time2ps, factor);
249         str += sprintf(str, "Histogram of I/O time between irq and end\n");
250         str = dasd_statistics_array(str, prof->dasd_io_time3, factor);
251         str += sprintf(str, "# of req in chanq at enqueuing (1..32) \n");
252         str = dasd_statistics_array(str, prof->dasd_io_nr_req, factor);
253         len = str - page;
254 #else
255         len = sprintf(page, "Statistics are not activated in this kernel\n");
256 #endif
257         return dasd_calc_metrics(page, start, off, count, eof, len);
258 }
259
260 static int
261 dasd_statistics_write(struct file *file, const char __user *user_buf,
262                       unsigned long user_len, void *data)
263 {
264 #ifdef CONFIG_DASD_PROFILE
265         char *buffer, *str;
266
267         if (user_len > 65536)
268                 user_len = 65536;
269         buffer = dasd_get_user_string(user_buf, user_len);
270         if (IS_ERR(buffer))
271                 return PTR_ERR(buffer);
272         DBF_EVENT(DBF_DEBUG, "/proc/dasd/statictics: '%s'\n", buffer);
273
274         /* check for valid verbs */
275         for (str = buffer; isspace(*str); str++);
276         if (strncmp(str, "set", 3) == 0 && isspace(str[3])) {
277                 /* 'set xxx' was given */
278                 for (str = str + 4; isspace(*str); str++);
279                 if (strcmp(str, "on") == 0) {
280                         /* switch on statistics profiling */
281                         dasd_profile_level = DASD_PROFILE_ON;
282                         pr_info("The statistics feature has been switched "
283                                 "on\n");
284                 } else if (strcmp(str, "off") == 0) {
285                         /* switch off and reset statistics profiling */
286                         memset(&dasd_global_profile,
287                                0, sizeof (struct dasd_profile_info_t));
288                         dasd_profile_level = DASD_PROFILE_OFF;
289                         pr_info("The statistics feature has been switched "
290                                 "off\n");
291                 } else
292                         goto out_error;
293         } else if (strncmp(str, "reset", 5) == 0) {
294                 /* reset the statistics */
295                 memset(&dasd_global_profile, 0,
296                        sizeof (struct dasd_profile_info_t));
297                 pr_info("The statistics have been reset\n");
298         } else
299                 goto out_error;
300         kfree(buffer);
301         return user_len;
302 out_error:
303         pr_warning("%s is not a supported value for /proc/dasd/statistics\n",
304                 str);
305         kfree(buffer);
306         return -EINVAL;
307 #else
308         pr_warning("/proc/dasd/statistics: is not activated in this kernel\n");
309         return user_len;
310 #endif                          /* CONFIG_DASD_PROFILE */
311 }
312
313 /*
314  * Create dasd proc-fs entries.
315  * In case creation failed, cleanup and return -ENOENT.
316  */
317 int
318 dasd_proc_init(void)
319 {
320         dasd_proc_root_entry = proc_mkdir("dasd", NULL);
321         if (!dasd_proc_root_entry)
322                 goto out_nodasd;
323         dasd_devices_entry = proc_create("devices",
324                                          S_IFREG | S_IRUGO | S_IWUSR,
325                                          dasd_proc_root_entry,
326                                          &dasd_devices_file_ops);
327         if (!dasd_devices_entry)
328                 goto out_nodevices;
329         dasd_statistics_entry = create_proc_entry("statistics",
330                                                   S_IFREG | S_IRUGO | S_IWUSR,
331                                                   dasd_proc_root_entry);
332         if (!dasd_statistics_entry)
333                 goto out_nostatistics;
334         dasd_statistics_entry->read_proc = dasd_statistics_read;
335         dasd_statistics_entry->write_proc = dasd_statistics_write;
336         return 0;
337
338  out_nostatistics:
339         remove_proc_entry("devices", dasd_proc_root_entry);
340  out_nodevices:
341         remove_proc_entry("dasd", NULL);
342  out_nodasd:
343         return -ENOENT;
344 }
345
346 void
347 dasd_proc_exit(void)
348 {
349         remove_proc_entry("devices", dasd_proc_root_entry);
350         remove_proc_entry("statistics", dasd_proc_root_entry);
351         remove_proc_entry("dasd", NULL);
352 }