xref: /openbmc/linux/drivers/scsi/scsi_proc.c (revision f35e839a)
1 /*
2  * linux/drivers/scsi/scsi_proc.c
3  *
4  * The functions in this file provide an interface between
5  * the PROC file system and the SCSI device drivers
6  * It is mainly used for debugging, statistics and to pass
7  * information directly to the lowlevel driver.
8  *
9  * (c) 1995 Michael Neuffer neuffer@goofy.zdv.uni-mainz.de
10  * Version: 0.99.8   last change: 95/09/13
11  *
12  * generic command parser provided by:
13  * Andreas Heilwagen <crashcar@informatik.uni-koblenz.de>
14  *
15  * generic_proc_info() support of xxxx_info() by:
16  * Michael A. Griffith <grif@acm.org>
17  */
18 
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <linux/string.h>
22 #include <linux/mm.h>
23 #include <linux/proc_fs.h>
24 #include <linux/errno.h>
25 #include <linux/blkdev.h>
26 #include <linux/seq_file.h>
27 #include <linux/mutex.h>
28 #include <linux/gfp.h>
29 #include <asm/uaccess.h>
30 
31 #include <scsi/scsi.h>
32 #include <scsi/scsi_device.h>
33 #include <scsi/scsi_host.h>
34 #include <scsi/scsi_transport.h>
35 
36 #include "scsi_priv.h"
37 #include "scsi_logging.h"
38 
39 
40 /* 4K page size, but our output routines, use some slack for overruns */
41 #define PROC_BLOCK_SIZE (3*1024)
42 
43 static struct proc_dir_entry *proc_scsi;
44 
45 /* Protect sht->present and sht->proc_dir */
46 static DEFINE_MUTEX(global_host_template_mutex);
47 
48 static ssize_t proc_scsi_host_write(struct file *file, const char __user *buf,
49                            size_t count, loff_t *ppos)
50 {
51 	struct Scsi_Host *shost = PDE_DATA(file_inode(file));
52 	ssize_t ret = -ENOMEM;
53 	char *page;
54 
55 	if (count > PROC_BLOCK_SIZE)
56 		return -EOVERFLOW;
57 
58 	if (!shost->hostt->write_info)
59 		return -EINVAL;
60 
61 	page = (char *)__get_free_page(GFP_KERNEL);
62 	if (page) {
63 		ret = -EFAULT;
64 		if (copy_from_user(page, buf, count))
65 			goto out;
66 		ret = shost->hostt->write_info(shost, page, count);
67 	}
68 out:
69 	free_page((unsigned long)page);
70 	return ret;
71 }
72 
73 static int proc_scsi_show(struct seq_file *m, void *v)
74 {
75 	struct Scsi_Host *shost = m->private;
76 	return shost->hostt->show_info(m, shost);
77 }
78 
79 static int proc_scsi_host_open(struct inode *inode, struct file *file)
80 {
81 	return single_open_size(file, proc_scsi_show, PDE_DATA(inode),
82 				4 * PAGE_SIZE);
83 }
84 
85 static const struct file_operations proc_scsi_fops = {
86 	.open = proc_scsi_host_open,
87 	.read = seq_read,
88 	.llseek = seq_lseek,
89 	.write = proc_scsi_host_write
90 };
91 
92 /**
93  * scsi_proc_hostdir_add - Create directory in /proc for a scsi host
94  * @sht: owner of this directory
95  *
96  * Sets sht->proc_dir to the new directory.
97  */
98 
99 void scsi_proc_hostdir_add(struct scsi_host_template *sht)
100 {
101 	if (!sht->show_info)
102 		return;
103 
104 	mutex_lock(&global_host_template_mutex);
105 	if (!sht->present++) {
106 		sht->proc_dir = proc_mkdir(sht->proc_name, proc_scsi);
107         	if (!sht->proc_dir)
108 			printk(KERN_ERR "%s: proc_mkdir failed for %s\n",
109 			       __func__, sht->proc_name);
110 	}
111 	mutex_unlock(&global_host_template_mutex);
112 }
113 
114 /**
115  * scsi_proc_hostdir_rm - remove directory in /proc for a scsi host
116  * @sht: owner of directory
117  */
118 void scsi_proc_hostdir_rm(struct scsi_host_template *sht)
119 {
120 	if (!sht->show_info)
121 		return;
122 
123 	mutex_lock(&global_host_template_mutex);
124 	if (!--sht->present && sht->proc_dir) {
125 		remove_proc_entry(sht->proc_name, proc_scsi);
126 		sht->proc_dir = NULL;
127 	}
128 	mutex_unlock(&global_host_template_mutex);
129 }
130 
131 
132 /**
133  * scsi_proc_host_add - Add entry for this host to appropriate /proc dir
134  * @shost: host to add
135  */
136 void scsi_proc_host_add(struct Scsi_Host *shost)
137 {
138 	struct scsi_host_template *sht = shost->hostt;
139 	struct proc_dir_entry *p;
140 	char name[10];
141 
142 	if (!sht->proc_dir)
143 		return;
144 
145 	sprintf(name,"%d", shost->host_no);
146 	p = proc_create_data(name, S_IRUGO | S_IWUSR,
147 		sht->proc_dir, &proc_scsi_fops, shost);
148 	if (!p)
149 		printk(KERN_ERR "%s: Failed to register host %d in"
150 		       "%s\n", __func__, shost->host_no,
151 		       sht->proc_name);
152 }
153 
154 /**
155  * scsi_proc_host_rm - remove this host's entry from /proc
156  * @shost: which host
157  */
158 void scsi_proc_host_rm(struct Scsi_Host *shost)
159 {
160 	char name[10];
161 
162 	if (!shost->hostt->proc_dir)
163 		return;
164 
165 	sprintf(name,"%d", shost->host_no);
166 	remove_proc_entry(name, shost->hostt->proc_dir);
167 }
168 /**
169  * proc_print_scsidevice - return data about this host
170  * @dev: A scsi device
171  * @data: &struct seq_file to output to.
172  *
173  * Description: prints Host, Channel, Id, Lun, Vendor, Model, Rev, Type,
174  * and revision.
175  */
176 static int proc_print_scsidevice(struct device *dev, void *data)
177 {
178 	struct scsi_device *sdev;
179 	struct seq_file *s = data;
180 	int i;
181 
182 	if (!scsi_is_sdev_device(dev))
183 		goto out;
184 
185 	sdev = to_scsi_device(dev);
186 	seq_printf(s,
187 		"Host: scsi%d Channel: %02d Id: %02d Lun: %02d\n  Vendor: ",
188 		sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
189 	for (i = 0; i < 8; i++) {
190 		if (sdev->vendor[i] >= 0x20)
191 			seq_printf(s, "%c", sdev->vendor[i]);
192 		else
193 			seq_printf(s, " ");
194 	}
195 
196 	seq_printf(s, " Model: ");
197 	for (i = 0; i < 16; i++) {
198 		if (sdev->model[i] >= 0x20)
199 			seq_printf(s, "%c", sdev->model[i]);
200 		else
201 			seq_printf(s, " ");
202 	}
203 
204 	seq_printf(s, " Rev: ");
205 	for (i = 0; i < 4; i++) {
206 		if (sdev->rev[i] >= 0x20)
207 			seq_printf(s, "%c", sdev->rev[i]);
208 		else
209 			seq_printf(s, " ");
210 	}
211 
212 	seq_printf(s, "\n");
213 
214 	seq_printf(s, "  Type:   %s ", scsi_device_type(sdev->type));
215 	seq_printf(s, "               ANSI  SCSI revision: %02x",
216 			sdev->scsi_level - (sdev->scsi_level > 1));
217 	if (sdev->scsi_level == 2)
218 		seq_printf(s, " CCS\n");
219 	else
220 		seq_printf(s, "\n");
221 
222 out:
223 	return 0;
224 }
225 
226 /**
227  * scsi_add_single_device - Respond to user request to probe for/add device
228  * @host: user-supplied decimal integer
229  * @channel: user-supplied decimal integer
230  * @id: user-supplied decimal integer
231  * @lun: user-supplied decimal integer
232  *
233  * Description: called by writing "scsi add-single-device" to /proc/scsi/scsi.
234  *
235  * does scsi_host_lookup() and either user_scan() if that transport
236  * type supports it, or else scsi_scan_host_selected()
237  *
238  * Note: this seems to be aimed exclusively at SCSI parallel busses.
239  */
240 
241 static int scsi_add_single_device(uint host, uint channel, uint id, uint lun)
242 {
243 	struct Scsi_Host *shost;
244 	int error = -ENXIO;
245 
246 	shost = scsi_host_lookup(host);
247 	if (!shost)
248 		return error;
249 
250 	if (shost->transportt->user_scan)
251 		error = shost->transportt->user_scan(shost, channel, id, lun);
252 	else
253 		error = scsi_scan_host_selected(shost, channel, id, lun, 1);
254 	scsi_host_put(shost);
255 	return error;
256 }
257 
258 /**
259  * scsi_remove_single_device - Respond to user request to remove a device
260  * @host: user-supplied decimal integer
261  * @channel: user-supplied decimal integer
262  * @id: user-supplied decimal integer
263  * @lun: user-supplied decimal integer
264  *
265  * Description: called by writing "scsi remove-single-device" to
266  * /proc/scsi/scsi.  Does a scsi_device_lookup() and scsi_remove_device()
267  */
268 static int scsi_remove_single_device(uint host, uint channel, uint id, uint lun)
269 {
270 	struct scsi_device *sdev;
271 	struct Scsi_Host *shost;
272 	int error = -ENXIO;
273 
274 	shost = scsi_host_lookup(host);
275 	if (!shost)
276 		return error;
277 	sdev = scsi_device_lookup(shost, channel, id, lun);
278 	if (sdev) {
279 		scsi_remove_device(sdev);
280 		scsi_device_put(sdev);
281 		error = 0;
282 	}
283 
284 	scsi_host_put(shost);
285 	return error;
286 }
287 
288 /**
289  * proc_scsi_write - handle writes to /proc/scsi/scsi
290  * @file: not used
291  * @buf: buffer to write
292  * @length: length of buf, at most PAGE_SIZE
293  * @ppos: not used
294  *
295  * Description: this provides a legacy mechanism to add or remove devices by
296  * Host, Channel, ID, and Lun.  To use,
297  * "echo 'scsi add-single-device 0 1 2 3' > /proc/scsi/scsi" or
298  * "echo 'scsi remove-single-device 0 1 2 3' > /proc/scsi/scsi" with
299  * "0 1 2 3" replaced by the Host, Channel, Id, and Lun.
300  *
301  * Note: this seems to be aimed at parallel SCSI. Most modern busses (USB,
302  * SATA, Firewire, Fibre Channel, etc) dynamically assign these values to
303  * provide a unique identifier and nothing more.
304  */
305 
306 
307 static ssize_t proc_scsi_write(struct file *file, const char __user *buf,
308 			       size_t length, loff_t *ppos)
309 {
310 	int host, channel, id, lun;
311 	char *buffer, *p;
312 	int err;
313 
314 	if (!buf || length > PAGE_SIZE)
315 		return -EINVAL;
316 
317 	buffer = (char *)__get_free_page(GFP_KERNEL);
318 	if (!buffer)
319 		return -ENOMEM;
320 
321 	err = -EFAULT;
322 	if (copy_from_user(buffer, buf, length))
323 		goto out;
324 
325 	err = -EINVAL;
326 	if (length < PAGE_SIZE)
327 		buffer[length] = '\0';
328 	else if (buffer[PAGE_SIZE-1])
329 		goto out;
330 
331 	/*
332 	 * Usage: echo "scsi add-single-device 0 1 2 3" >/proc/scsi/scsi
333 	 * with  "0 1 2 3" replaced by your "Host Channel Id Lun".
334 	 */
335 	if (!strncmp("scsi add-single-device", buffer, 22)) {
336 		p = buffer + 23;
337 
338 		host = simple_strtoul(p, &p, 0);
339 		channel = simple_strtoul(p + 1, &p, 0);
340 		id = simple_strtoul(p + 1, &p, 0);
341 		lun = simple_strtoul(p + 1, &p, 0);
342 
343 		err = scsi_add_single_device(host, channel, id, lun);
344 
345 	/*
346 	 * Usage: echo "scsi remove-single-device 0 1 2 3" >/proc/scsi/scsi
347 	 * with  "0 1 2 3" replaced by your "Host Channel Id Lun".
348 	 */
349 	} else if (!strncmp("scsi remove-single-device", buffer, 25)) {
350 		p = buffer + 26;
351 
352 		host = simple_strtoul(p, &p, 0);
353 		channel = simple_strtoul(p + 1, &p, 0);
354 		id = simple_strtoul(p + 1, &p, 0);
355 		lun = simple_strtoul(p + 1, &p, 0);
356 
357 		err = scsi_remove_single_device(host, channel, id, lun);
358 	}
359 
360 	/*
361 	 * convert success returns so that we return the
362 	 * number of bytes consumed.
363 	 */
364 	if (!err)
365 		err = length;
366 
367  out:
368 	free_page((unsigned long)buffer);
369 	return err;
370 }
371 
372 static int always_match(struct device *dev, void *data)
373 {
374 	return 1;
375 }
376 
377 static inline struct device *next_scsi_device(struct device *start)
378 {
379 	struct device *next = bus_find_device(&scsi_bus_type, start, NULL,
380 					      always_match);
381 	put_device(start);
382 	return next;
383 }
384 
385 static void *scsi_seq_start(struct seq_file *sfile, loff_t *pos)
386 {
387 	struct device *dev = NULL;
388 	loff_t n = *pos;
389 
390 	while ((dev = next_scsi_device(dev))) {
391 		if (!n--)
392 			break;
393 		sfile->private++;
394 	}
395 	return dev;
396 }
397 
398 static void *scsi_seq_next(struct seq_file *sfile, void *v, loff_t *pos)
399 {
400 	(*pos)++;
401 	sfile->private++;
402 	return next_scsi_device(v);
403 }
404 
405 static void scsi_seq_stop(struct seq_file *sfile, void *v)
406 {
407 	put_device(v);
408 }
409 
410 static int scsi_seq_show(struct seq_file *sfile, void *dev)
411 {
412 	if (!sfile->private)
413 		seq_puts(sfile, "Attached devices:\n");
414 
415 	return proc_print_scsidevice(dev, sfile);
416 }
417 
418 static const struct seq_operations scsi_seq_ops = {
419 	.start	= scsi_seq_start,
420 	.next	= scsi_seq_next,
421 	.stop	= scsi_seq_stop,
422 	.show	= scsi_seq_show
423 };
424 
425 /**
426  * proc_scsi_open - glue function
427  * @inode: not used
428  * @file: passed to single_open()
429  *
430  * Associates proc_scsi_show with this file
431  */
432 static int proc_scsi_open(struct inode *inode, struct file *file)
433 {
434 	/*
435 	 * We don't really need this for the write case but it doesn't
436 	 * harm either.
437 	 */
438 	return seq_open(file, &scsi_seq_ops);
439 }
440 
441 static const struct file_operations proc_scsi_operations = {
442 	.owner		= THIS_MODULE,
443 	.open		= proc_scsi_open,
444 	.read		= seq_read,
445 	.write		= proc_scsi_write,
446 	.llseek		= seq_lseek,
447 	.release	= seq_release,
448 };
449 
450 /**
451  * scsi_init_procfs - create scsi and scsi/scsi in procfs
452  */
453 int __init scsi_init_procfs(void)
454 {
455 	struct proc_dir_entry *pde;
456 
457 	proc_scsi = proc_mkdir("scsi", NULL);
458 	if (!proc_scsi)
459 		goto err1;
460 
461 	pde = proc_create("scsi/scsi", 0, NULL, &proc_scsi_operations);
462 	if (!pde)
463 		goto err2;
464 
465 	return 0;
466 
467 err2:
468 	remove_proc_entry("scsi", NULL);
469 err1:
470 	return -ENOMEM;
471 }
472 
473 /**
474  * scsi_exit_procfs - Remove scsi/scsi and scsi from procfs
475  */
476 void scsi_exit_procfs(void)
477 {
478 	remove_proc_entry("scsi/scsi", NULL);
479 	remove_proc_entry("scsi", NULL);
480 }
481