tree-wide: convert open calls to remove spaces to skip_spaces() lib function
[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 #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 != NULL && 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 != NULL) ? device->state : -1) {
96         case -1:
97                 seq_printf(m, "unknown");
98                 break;
99         case DASD_STATE_NEW:
100                 seq_printf(m, "new");
101                 break;
102         case DASD_STATE_KNOWN:
103                 seq_printf(m, "detected");
104                 break;
105         case DASD_STATE_BASIC:
106                 seq_printf(m, "basic");
107                 break;
108         case DASD_STATE_UNFMT:
109                 seq_printf(m, "unformatted");
110                 break;
111         case DASD_STATE_READY:
112         case DASD_STATE_ONLINE:
113                 seq_printf(m, "active ");
114                 if (dasd_check_blocksize(block->bp_block))
115                         seq_printf(m, "n/f       ");
116                 else
117                         seq_printf(m,
118                                    "at blocksize: %d, %lld blocks, %lld MB",
119                                    block->bp_block, block->blocks,
120                                    ((block->bp_block >> 9) *
121                                     block->blocks) >> 11);
122                 break;
123         default:
124                 seq_printf(m, "no stat");
125                 break;
126         }
127         dasd_put_device(device);
128         if (dasd_probeonly)
129                 seq_printf(m, "(probeonly)");
130         seq_printf(m, "\n");
131         return 0;
132 }
133
134 static void *dasd_devices_start(struct seq_file *m, loff_t *pos)
135 {
136         if (*pos >= dasd_max_devindex)
137                 return NULL;
138         return (void *)((unsigned long) *pos + 1);
139 }
140
141 static void *dasd_devices_next(struct seq_file *m, void *v, loff_t *pos)
142 {
143         ++*pos;
144         return dasd_devices_start(m, pos);
145 }
146
147 static void dasd_devices_stop(struct seq_file *m, void *v)
148 {
149 }
150
151 static const struct seq_operations dasd_devices_seq_ops = {
152         .start          = dasd_devices_start,
153         .next           = dasd_devices_next,
154         .stop           = dasd_devices_stop,
155         .show           = dasd_devices_show,
156 };
157
158 static int dasd_devices_open(struct inode *inode, struct file *file)
159 {
160         return seq_open(file, &dasd_devices_seq_ops);
161 }
162
163 static const struct file_operations dasd_devices_file_ops = {
164         .owner          = THIS_MODULE,
165         .open           = dasd_devices_open,
166         .read           = seq_read,
167         .llseek         = seq_lseek,
168         .release        = seq_release,
169 };
170
171 static int
172 dasd_calc_metrics(char *page, char **start, off_t off,
173                   int count, int *eof, int len)
174 {
175         len = (len > off) ? len - off : 0;
176         if (len > count)
177                 len = count;
178         if (len < count)
179                 *eof = 1;
180         *start = page + off;
181         return len;
182 }
183
184 #ifdef CONFIG_DASD_PROFILE
185 static char *
186 dasd_statistics_array(char *str, unsigned int *array, int factor)
187 {
188         int i;
189
190         for (i = 0; i < 32; i++) {
191                 str += sprintf(str, "%7d ", array[i] / factor);
192                 if (i == 15)
193                         str += sprintf(str, "\n");
194         }
195         str += sprintf(str,"\n");
196         return str;
197 }
198 #endif /* CONFIG_DASD_PROFILE */
199
200 static int
201 dasd_statistics_read(char *page, char **start, off_t off,
202                      int count, int *eof, void *data)
203 {
204         unsigned long len;
205 #ifdef CONFIG_DASD_PROFILE
206         struct dasd_profile_info_t *prof;
207         char *str;
208         int factor;
209
210         /* check for active profiling */
211         if (dasd_profile_level == DASD_PROFILE_OFF) {
212                 len = sprintf(page, "Statistics are off - they might be "
213                                     "switched on using 'echo set on > "
214                                     "/proc/dasd/statistics'\n");
215                 return dasd_calc_metrics(page, start, off, count, eof, len);
216         }
217
218         prof = &dasd_global_profile;
219         /* prevent counter 'overflow' on output */
220         for (factor = 1; (prof->dasd_io_reqs / factor) > 9999999;
221              factor *= 10);
222
223         str = page;
224         str += sprintf(str, "%d dasd I/O requests\n", prof->dasd_io_reqs);
225         str += sprintf(str, "with %u sectors(512B each)\n",
226                        prof->dasd_io_sects);
227         str += sprintf(str, "Scale Factor is  %d\n", factor);
228         str += sprintf(str,
229                        "   __<4    ___8    __16    __32    __64    _128 "
230                        "   _256    _512    __1k    __2k    __4k    __8k "
231                        "   _16k    _32k    _64k    128k\n");
232         str += sprintf(str,
233                        "   _256    _512    __1M    __2M    __4M    __8M "
234                        "   _16M    _32M    _64M    128M    256M    512M "
235                        "   __1G    __2G    __4G " "   _>4G\n");
236
237         str += sprintf(str, "Histogram of sizes (512B secs)\n");
238         str = dasd_statistics_array(str, prof->dasd_io_secs, factor);
239         str += sprintf(str, "Histogram of I/O times (microseconds)\n");
240         str = dasd_statistics_array(str, prof->dasd_io_times, factor);
241         str += sprintf(str, "Histogram of I/O times per sector\n");
242         str = dasd_statistics_array(str, prof->dasd_io_timps, factor);
243         str += sprintf(str, "Histogram of I/O time till ssch\n");
244         str = dasd_statistics_array(str, prof->dasd_io_time1, factor);
245         str += sprintf(str, "Histogram of I/O time between ssch and irq\n");
246         str = dasd_statistics_array(str, prof->dasd_io_time2, factor);
247         str += sprintf(str, "Histogram of I/O time between ssch "
248                             "and irq per sector\n");
249         str = dasd_statistics_array(str, prof->dasd_io_time2ps, factor);
250         str += sprintf(str, "Histogram of I/O time between irq and end\n");
251         str = dasd_statistics_array(str, prof->dasd_io_time3, factor);
252         str += sprintf(str, "# of req in chanq at enqueuing (1..32) \n");
253         str = dasd_statistics_array(str, prof->dasd_io_nr_req, factor);
254         len = str - page;
255 #else
256         len = sprintf(page, "Statistics are not activated in this kernel\n");
257 #endif
258         return dasd_calc_metrics(page, start, off, count, eof, len);
259 }
260
261 static int
262 dasd_statistics_write(struct file *file, const char __user *user_buf,
263                       unsigned long user_len, void *data)
264 {
265 #ifdef CONFIG_DASD_PROFILE
266         char *buffer, *str;
267
268         if (user_len > 65536)
269                 user_len = 65536;
270         buffer = dasd_get_user_string(user_buf, user_len);
271         if (IS_ERR(buffer))
272                 return PTR_ERR(buffer);
273         DBF_EVENT(DBF_DEBUG, "/proc/dasd/statictics: '%s'\n", buffer);
274
275         /* check for valid verbs */
276         str = skip_spaces(buffer);
277         if (strncmp(str, "set", 3) == 0 && isspace(str[3])) {
278                 /* 'set xxx' was given */
279                 str = skip_spaces(str + 4);
280                 if (strcmp(str, "on") == 0) {
281                         /* switch on statistics profiling */
282                         dasd_profile_level = DASD_PROFILE_ON;
283                         pr_info("The statistics feature has been switched "
284                                 "on\n");
285                 } else if (strcmp(str, "off") == 0) {
286                         /* switch off and reset statistics profiling */
287                         memset(&dasd_global_profile,
288                                0, sizeof (struct dasd_profile_info_t));
289                         dasd_profile_level = DASD_PROFILE_OFF;
290                         pr_info("The statistics feature has been switched "
291                                 "off\n");
292                 } else
293                         goto out_error;
294         } else if (strncmp(str, "reset", 5) == 0) {
295                 /* reset the statistics */
296                 memset(&dasd_global_profile, 0,
297                        sizeof (struct dasd_profile_info_t));
298                 pr_info("The statistics have been reset\n");
299         } else
300                 goto out_error;
301         kfree(buffer);
302         return user_len;
303 out_error:
304         pr_warning("%s is not a supported value for /proc/dasd/statistics\n",
305                 str);
306         kfree(buffer);
307         return -EINVAL;
308 #else
309         pr_warning("/proc/dasd/statistics: is not activated in this kernel\n");
310         return user_len;
311 #endif                          /* CONFIG_DASD_PROFILE */
312 }
313
314 /*
315  * Create dasd proc-fs entries.
316  * In case creation failed, cleanup and return -ENOENT.
317  */
318 int
319 dasd_proc_init(void)
320 {
321         dasd_proc_root_entry = proc_mkdir("dasd", NULL);
322         if (!dasd_proc_root_entry)
323                 goto out_nodasd;
324         dasd_devices_entry = proc_create("devices",
325                                          S_IFREG | S_IRUGO | S_IWUSR,
326                                          dasd_proc_root_entry,
327                                          &dasd_devices_file_ops);
328         if (!dasd_devices_entry)
329                 goto out_nodevices;
330         dasd_statistics_entry = create_proc_entry("statistics",
331                                                   S_IFREG | S_IRUGO | S_IWUSR,
332                                                   dasd_proc_root_entry);
333         if (!dasd_statistics_entry)
334                 goto out_nostatistics;
335         dasd_statistics_entry->read_proc = dasd_statistics_read;
336         dasd_statistics_entry->write_proc = dasd_statistics_write;
337         return 0;
338
339  out_nostatistics:
340         remove_proc_entry("devices", dasd_proc_root_entry);
341  out_nodevices:
342         remove_proc_entry("dasd", NULL);
343  out_nodasd:
344         return -ENOENT;
345 }
346
347 void
348 dasd_proc_exit(void)
349 {
350         remove_proc_entry("devices", dasd_proc_root_entry);
351         remove_proc_entry("statistics", dasd_proc_root_entry);
352         remove_proc_entry("dasd", NULL);
353 }