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