1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * linux/drivers/scsi/scsi_proc.c |
4 | * |
5 | * The functions in this file provide an interface between |
6 | * the PROC file system and the SCSI device drivers |
7 | * It is mainly used for debugging, statistics and to pass |
8 | * information directly to the lowlevel driver. |
9 | * |
10 | * (c) 1995 Michael Neuffer neuffer@goofy.zdv.uni-mainz.de |
11 | * Version: 0.99.8 last change: 95/09/13 |
12 | * |
13 | * generic command parser provided by: |
14 | * Andreas Heilwagen <crashcar@informatik.uni-koblenz.de> |
15 | * |
16 | * generic_proc_info() support of xxxx_info() by: |
17 | * Michael A. Griffith <grif@acm.org> |
18 | */ |
19 | |
20 | #include <linux/module.h> |
21 | #include <linux/init.h> |
22 | #include <linux/string.h> |
23 | #include <linux/mm.h> |
24 | #include <linux/proc_fs.h> |
25 | #include <linux/errno.h> |
26 | #include <linux/blkdev.h> |
27 | #include <linux/seq_file.h> |
28 | #include <linux/mutex.h> |
29 | #include <linux/gfp.h> |
30 | #include <linux/uaccess.h> |
31 | |
32 | #include <scsi/scsi.h> |
33 | #include <scsi/scsi_device.h> |
34 | #include <scsi/scsi_host.h> |
35 | #include <scsi/scsi_transport.h> |
36 | |
37 | #include "scsi_priv.h" |
38 | #include "scsi_logging.h" |
39 | |
40 | |
41 | /* 4K page size, but our output routines, use some slack for overruns */ |
42 | #define PROC_BLOCK_SIZE (3*1024) |
43 | |
44 | static struct proc_dir_entry *proc_scsi; |
45 | |
46 | /* Protects scsi_proc_list */ |
47 | static DEFINE_MUTEX(global_host_template_mutex); |
48 | static LIST_HEAD(scsi_proc_list); |
49 | |
50 | /** |
51 | * struct scsi_proc_entry - (host template, SCSI proc dir) association |
52 | * @entry: entry in scsi_proc_list. |
53 | * @sht: SCSI host template associated with the procfs directory. |
54 | * @proc_dir: procfs directory associated with the SCSI host template. |
55 | * @present: Number of SCSI hosts instantiated for @sht. |
56 | */ |
57 | struct scsi_proc_entry { |
58 | struct list_head entry; |
59 | const struct scsi_host_template *sht; |
60 | struct proc_dir_entry *proc_dir; |
61 | unsigned int present; |
62 | }; |
63 | |
64 | static ssize_t proc_scsi_host_write(struct file *file, const char __user *buf, |
65 | size_t count, loff_t *ppos) |
66 | { |
67 | struct Scsi_Host *shost = pde_data(inode: file_inode(f: file)); |
68 | ssize_t ret = -ENOMEM; |
69 | char *page; |
70 | |
71 | if (count > PROC_BLOCK_SIZE) |
72 | return -EOVERFLOW; |
73 | |
74 | if (!shost->hostt->write_info) |
75 | return -EINVAL; |
76 | |
77 | page = (char *)__get_free_page(GFP_KERNEL); |
78 | if (page) { |
79 | ret = -EFAULT; |
80 | if (copy_from_user(to: page, from: buf, n: count)) |
81 | goto out; |
82 | ret = shost->hostt->write_info(shost, page, count); |
83 | } |
84 | out: |
85 | free_page((unsigned long)page); |
86 | return ret; |
87 | } |
88 | |
89 | static int proc_scsi_show(struct seq_file *m, void *v) |
90 | { |
91 | struct Scsi_Host *shost = m->private; |
92 | return shost->hostt->show_info(m, shost); |
93 | } |
94 | |
95 | static int proc_scsi_host_open(struct inode *inode, struct file *file) |
96 | { |
97 | return single_open_size(file, proc_scsi_show, pde_data(inode), |
98 | 4 * PAGE_SIZE); |
99 | } |
100 | |
101 | static struct scsi_proc_entry * |
102 | __scsi_lookup_proc_entry(const struct scsi_host_template *sht) |
103 | { |
104 | struct scsi_proc_entry *e; |
105 | |
106 | lockdep_assert_held(&global_host_template_mutex); |
107 | |
108 | list_for_each_entry(e, &scsi_proc_list, entry) |
109 | if (e->sht == sht) |
110 | return e; |
111 | |
112 | return NULL; |
113 | } |
114 | |
115 | static struct scsi_proc_entry * |
116 | scsi_lookup_proc_entry(const struct scsi_host_template *sht) |
117 | { |
118 | struct scsi_proc_entry *e; |
119 | |
120 | mutex_lock(&global_host_template_mutex); |
121 | e = __scsi_lookup_proc_entry(sht); |
122 | mutex_unlock(lock: &global_host_template_mutex); |
123 | |
124 | return e; |
125 | } |
126 | |
127 | /** |
128 | * scsi_template_proc_dir() - returns the procfs dir for a SCSI host template |
129 | * @sht: SCSI host template pointer. |
130 | */ |
131 | struct proc_dir_entry * |
132 | scsi_template_proc_dir(const struct scsi_host_template *sht) |
133 | { |
134 | struct scsi_proc_entry *e = scsi_lookup_proc_entry(sht); |
135 | |
136 | return e ? e->proc_dir : NULL; |
137 | } |
138 | EXPORT_SYMBOL_GPL(scsi_template_proc_dir); |
139 | |
140 | static const struct proc_ops proc_scsi_ops = { |
141 | .proc_open = proc_scsi_host_open, |
142 | .proc_release = single_release, |
143 | .proc_read = seq_read, |
144 | .proc_lseek = seq_lseek, |
145 | .proc_write = proc_scsi_host_write |
146 | }; |
147 | |
148 | /** |
149 | * scsi_proc_hostdir_add - Create directory in /proc for a scsi host |
150 | * @sht: owner of this directory |
151 | * |
152 | * Sets sht->proc_dir to the new directory. |
153 | */ |
154 | int scsi_proc_hostdir_add(const struct scsi_host_template *sht) |
155 | { |
156 | struct scsi_proc_entry *e; |
157 | int ret; |
158 | |
159 | if (!sht->show_info) |
160 | return 0; |
161 | |
162 | mutex_lock(&global_host_template_mutex); |
163 | e = __scsi_lookup_proc_entry(sht); |
164 | if (!e) { |
165 | e = kzalloc(size: sizeof(*e), GFP_KERNEL); |
166 | if (!e) { |
167 | ret = -ENOMEM; |
168 | goto unlock; |
169 | } |
170 | } |
171 | if (e->present++) |
172 | goto success; |
173 | e->proc_dir = proc_mkdir(sht->proc_name, proc_scsi); |
174 | if (!e->proc_dir) { |
175 | printk(KERN_ERR "%s: proc_mkdir failed for %s\n" , __func__, |
176 | sht->proc_name); |
177 | ret = -ENOMEM; |
178 | goto unlock; |
179 | } |
180 | e->sht = sht; |
181 | list_add_tail(new: &e->entry, head: &scsi_proc_list); |
182 | success: |
183 | e = NULL; |
184 | ret = 0; |
185 | unlock: |
186 | mutex_unlock(lock: &global_host_template_mutex); |
187 | |
188 | kfree(objp: e); |
189 | return ret; |
190 | } |
191 | |
192 | /** |
193 | * scsi_proc_hostdir_rm - remove directory in /proc for a scsi host |
194 | * @sht: owner of directory |
195 | */ |
196 | void scsi_proc_hostdir_rm(const struct scsi_host_template *sht) |
197 | { |
198 | struct scsi_proc_entry *e; |
199 | |
200 | if (!sht->show_info) |
201 | return; |
202 | |
203 | mutex_lock(&global_host_template_mutex); |
204 | e = __scsi_lookup_proc_entry(sht); |
205 | if (e && !--e->present) { |
206 | remove_proc_entry(sht->proc_name, proc_scsi); |
207 | list_del(entry: &e->entry); |
208 | kfree(objp: e); |
209 | } |
210 | mutex_unlock(lock: &global_host_template_mutex); |
211 | } |
212 | |
213 | |
214 | /** |
215 | * scsi_proc_host_add - Add entry for this host to appropriate /proc dir |
216 | * @shost: host to add |
217 | */ |
218 | void scsi_proc_host_add(struct Scsi_Host *shost) |
219 | { |
220 | const struct scsi_host_template *sht = shost->hostt; |
221 | struct scsi_proc_entry *e; |
222 | struct proc_dir_entry *p; |
223 | char name[10]; |
224 | |
225 | if (!sht->show_info) |
226 | return; |
227 | |
228 | e = scsi_lookup_proc_entry(sht); |
229 | if (!e) |
230 | goto err; |
231 | |
232 | sprintf(buf: name,fmt: "%d" , shost->host_no); |
233 | p = proc_create_data(name, S_IRUGO | S_IWUSR, e->proc_dir, |
234 | &proc_scsi_ops, shost); |
235 | if (!p) |
236 | goto err; |
237 | return; |
238 | |
239 | err: |
240 | shost_printk(KERN_ERR, shost, |
241 | "%s: Failed to register host (%s failed)\n" , __func__, |
242 | e ? "proc_create_data()" : "scsi_proc_hostdir_add()" ); |
243 | } |
244 | |
245 | /** |
246 | * scsi_proc_host_rm - remove this host's entry from /proc |
247 | * @shost: which host |
248 | */ |
249 | void scsi_proc_host_rm(struct Scsi_Host *shost) |
250 | { |
251 | const struct scsi_host_template *sht = shost->hostt; |
252 | struct scsi_proc_entry *e; |
253 | char name[10]; |
254 | |
255 | if (!sht->show_info) |
256 | return; |
257 | |
258 | e = scsi_lookup_proc_entry(sht); |
259 | if (!e) |
260 | return; |
261 | |
262 | sprintf(buf: name,fmt: "%d" , shost->host_no); |
263 | remove_proc_entry(name, e->proc_dir); |
264 | } |
265 | /** |
266 | * proc_print_scsidevice - return data about this host |
267 | * @dev: A scsi device |
268 | * @data: &struct seq_file to output to. |
269 | * |
270 | * Description: prints Host, Channel, Id, Lun, Vendor, Model, Rev, Type, |
271 | * and revision. |
272 | */ |
273 | static int proc_print_scsidevice(struct device *dev, void *data) |
274 | { |
275 | struct scsi_device *sdev; |
276 | struct seq_file *s = data; |
277 | int i; |
278 | |
279 | if (!scsi_is_sdev_device(dev)) |
280 | goto out; |
281 | |
282 | sdev = to_scsi_device(dev); |
283 | seq_printf(m: s, |
284 | fmt: "Host: scsi%d Channel: %02d Id: %02d Lun: %02llu\n Vendor: " , |
285 | sdev->host->host_no, sdev->channel, sdev->id, sdev->lun); |
286 | for (i = 0; i < 8; i++) { |
287 | if (sdev->vendor[i] >= 0x20) |
288 | seq_putc(m: s, c: sdev->vendor[i]); |
289 | else |
290 | seq_putc(m: s, c: ' '); |
291 | } |
292 | |
293 | seq_puts(m: s, s: " Model: " ); |
294 | for (i = 0; i < 16; i++) { |
295 | if (sdev->model[i] >= 0x20) |
296 | seq_putc(m: s, c: sdev->model[i]); |
297 | else |
298 | seq_putc(m: s, c: ' '); |
299 | } |
300 | |
301 | seq_puts(m: s, s: " Rev: " ); |
302 | for (i = 0; i < 4; i++) { |
303 | if (sdev->rev[i] >= 0x20) |
304 | seq_putc(m: s, c: sdev->rev[i]); |
305 | else |
306 | seq_putc(m: s, c: ' '); |
307 | } |
308 | |
309 | seq_putc(m: s, c: '\n'); |
310 | |
311 | seq_printf(m: s, fmt: " Type: %s " , scsi_device_type(type: sdev->type)); |
312 | seq_printf(m: s, fmt: " ANSI SCSI revision: %02x" , |
313 | sdev->scsi_level - (sdev->scsi_level > 1)); |
314 | if (sdev->scsi_level == 2) |
315 | seq_puts(m: s, s: " CCS\n" ); |
316 | else |
317 | seq_putc(m: s, c: '\n'); |
318 | |
319 | out: |
320 | return 0; |
321 | } |
322 | |
323 | /** |
324 | * scsi_add_single_device - Respond to user request to probe for/add device |
325 | * @host: user-supplied decimal integer |
326 | * @channel: user-supplied decimal integer |
327 | * @id: user-supplied decimal integer |
328 | * @lun: user-supplied decimal integer |
329 | * |
330 | * Description: called by writing "scsi add-single-device" to /proc/scsi/scsi. |
331 | * |
332 | * does scsi_host_lookup() and either user_scan() if that transport |
333 | * type supports it, or else scsi_scan_host_selected() |
334 | * |
335 | * Note: this seems to be aimed exclusively at SCSI parallel busses. |
336 | */ |
337 | |
338 | static int scsi_add_single_device(uint host, uint channel, uint id, uint lun) |
339 | { |
340 | struct Scsi_Host *shost; |
341 | int error = -ENXIO; |
342 | |
343 | shost = scsi_host_lookup(hostnum: host); |
344 | if (!shost) |
345 | return error; |
346 | |
347 | if (shost->transportt->user_scan) |
348 | error = shost->transportt->user_scan(shost, channel, id, lun); |
349 | else |
350 | error = scsi_scan_host_selected(shost, channel, id, lun, |
351 | SCSI_SCAN_MANUAL); |
352 | scsi_host_put(t: shost); |
353 | return error; |
354 | } |
355 | |
356 | /** |
357 | * scsi_remove_single_device - Respond to user request to remove a device |
358 | * @host: user-supplied decimal integer |
359 | * @channel: user-supplied decimal integer |
360 | * @id: user-supplied decimal integer |
361 | * @lun: user-supplied decimal integer |
362 | * |
363 | * Description: called by writing "scsi remove-single-device" to |
364 | * /proc/scsi/scsi. Does a scsi_device_lookup() and scsi_remove_device() |
365 | */ |
366 | static int scsi_remove_single_device(uint host, uint channel, uint id, uint lun) |
367 | { |
368 | struct scsi_device *sdev; |
369 | struct Scsi_Host *shost; |
370 | int error = -ENXIO; |
371 | |
372 | shost = scsi_host_lookup(hostnum: host); |
373 | if (!shost) |
374 | return error; |
375 | sdev = scsi_device_lookup(shost, channel, id, lun); |
376 | if (sdev) { |
377 | scsi_remove_device(sdev); |
378 | scsi_device_put(sdev); |
379 | error = 0; |
380 | } |
381 | |
382 | scsi_host_put(t: shost); |
383 | return error; |
384 | } |
385 | |
386 | /** |
387 | * proc_scsi_write - handle writes to /proc/scsi/scsi |
388 | * @file: not used |
389 | * @buf: buffer to write |
390 | * @length: length of buf, at most PAGE_SIZE |
391 | * @ppos: not used |
392 | * |
393 | * Description: this provides a legacy mechanism to add or remove devices by |
394 | * Host, Channel, ID, and Lun. To use, |
395 | * "echo 'scsi add-single-device 0 1 2 3' > /proc/scsi/scsi" or |
396 | * "echo 'scsi remove-single-device 0 1 2 3' > /proc/scsi/scsi" with |
397 | * "0 1 2 3" replaced by the Host, Channel, Id, and Lun. |
398 | * |
399 | * Note: this seems to be aimed at parallel SCSI. Most modern busses (USB, |
400 | * SATA, Firewire, Fibre Channel, etc) dynamically assign these values to |
401 | * provide a unique identifier and nothing more. |
402 | */ |
403 | |
404 | |
405 | static ssize_t proc_scsi_write(struct file *file, const char __user *buf, |
406 | size_t length, loff_t *ppos) |
407 | { |
408 | int host, channel, id, lun; |
409 | char *buffer, *end, *p; |
410 | int err; |
411 | |
412 | if (!buf || length > PAGE_SIZE) |
413 | return -EINVAL; |
414 | |
415 | buffer = (char *)__get_free_page(GFP_KERNEL); |
416 | if (!buffer) |
417 | return -ENOMEM; |
418 | |
419 | err = -EFAULT; |
420 | if (copy_from_user(to: buffer, from: buf, n: length)) |
421 | goto out; |
422 | |
423 | err = -EINVAL; |
424 | if (length < PAGE_SIZE) { |
425 | end = buffer + length; |
426 | *end = '\0'; |
427 | } else { |
428 | end = buffer + PAGE_SIZE - 1; |
429 | if (*end) |
430 | goto out; |
431 | } |
432 | |
433 | /* |
434 | * Usage: echo "scsi add-single-device 0 1 2 3" >/proc/scsi/scsi |
435 | * with "0 1 2 3" replaced by your "Host Channel Id Lun". |
436 | */ |
437 | if (!strncmp("scsi add-single-device" , buffer, 22)) { |
438 | p = buffer + 23; |
439 | |
440 | host = (p < end) ? simple_strtoul(p, &p, 0) : 0; |
441 | channel = (p + 1 < end) ? simple_strtoul(p + 1, &p, 0) : 0; |
442 | id = (p + 1 < end) ? simple_strtoul(p + 1, &p, 0) : 0; |
443 | lun = (p + 1 < end) ? simple_strtoul(p + 1, &p, 0) : 0; |
444 | |
445 | err = scsi_add_single_device(host, channel, id, lun); |
446 | |
447 | /* |
448 | * Usage: echo "scsi remove-single-device 0 1 2 3" >/proc/scsi/scsi |
449 | * with "0 1 2 3" replaced by your "Host Channel Id Lun". |
450 | */ |
451 | } else if (!strncmp("scsi remove-single-device" , buffer, 25)) { |
452 | p = buffer + 26; |
453 | |
454 | host = (p < end) ? simple_strtoul(p, &p, 0) : 0; |
455 | channel = (p + 1 < end) ? simple_strtoul(p + 1, &p, 0) : 0; |
456 | id = (p + 1 < end) ? simple_strtoul(p + 1, &p, 0) : 0; |
457 | lun = (p + 1 < end) ? simple_strtoul(p + 1, &p, 0) : 0; |
458 | |
459 | err = scsi_remove_single_device(host, channel, id, lun); |
460 | } |
461 | |
462 | /* |
463 | * convert success returns so that we return the |
464 | * number of bytes consumed. |
465 | */ |
466 | if (!err) |
467 | err = length; |
468 | |
469 | out: |
470 | free_page((unsigned long)buffer); |
471 | return err; |
472 | } |
473 | |
474 | static inline struct device *next_scsi_device(struct device *start) |
475 | { |
476 | struct device *next = bus_find_next_device(bus: &scsi_bus_type, cur: start); |
477 | |
478 | put_device(dev: start); |
479 | return next; |
480 | } |
481 | |
482 | static void *scsi_seq_start(struct seq_file *sfile, loff_t *pos) |
483 | { |
484 | struct device *dev = NULL; |
485 | loff_t n = *pos; |
486 | |
487 | while ((dev = next_scsi_device(start: dev))) { |
488 | if (!n--) |
489 | break; |
490 | sfile->private++; |
491 | } |
492 | return dev; |
493 | } |
494 | |
495 | static void *scsi_seq_next(struct seq_file *sfile, void *v, loff_t *pos) |
496 | { |
497 | (*pos)++; |
498 | sfile->private++; |
499 | return next_scsi_device(start: v); |
500 | } |
501 | |
502 | static void scsi_seq_stop(struct seq_file *sfile, void *v) |
503 | { |
504 | put_device(dev: v); |
505 | } |
506 | |
507 | static int scsi_seq_show(struct seq_file *sfile, void *dev) |
508 | { |
509 | if (!sfile->private) |
510 | seq_puts(m: sfile, s: "Attached devices:\n" ); |
511 | |
512 | return proc_print_scsidevice(dev, data: sfile); |
513 | } |
514 | |
515 | static const struct seq_operations scsi_seq_ops = { |
516 | .start = scsi_seq_start, |
517 | .next = scsi_seq_next, |
518 | .stop = scsi_seq_stop, |
519 | .show = scsi_seq_show |
520 | }; |
521 | |
522 | /** |
523 | * proc_scsi_open - glue function |
524 | * @inode: not used |
525 | * @file: passed to single_open() |
526 | * |
527 | * Associates proc_scsi_show with this file |
528 | */ |
529 | static int proc_scsi_open(struct inode *inode, struct file *file) |
530 | { |
531 | /* |
532 | * We don't really need this for the write case but it doesn't |
533 | * harm either. |
534 | */ |
535 | return seq_open(file, &scsi_seq_ops); |
536 | } |
537 | |
538 | static const struct proc_ops scsi_scsi_proc_ops = { |
539 | .proc_open = proc_scsi_open, |
540 | .proc_read = seq_read, |
541 | .proc_write = proc_scsi_write, |
542 | .proc_lseek = seq_lseek, |
543 | .proc_release = seq_release, |
544 | }; |
545 | |
546 | /** |
547 | * scsi_init_procfs - create scsi and scsi/scsi in procfs |
548 | */ |
549 | int __init scsi_init_procfs(void) |
550 | { |
551 | struct proc_dir_entry *pde; |
552 | |
553 | proc_scsi = proc_mkdir("scsi" , NULL); |
554 | if (!proc_scsi) |
555 | goto err1; |
556 | |
557 | pde = proc_create(name: "scsi/scsi" , mode: 0, NULL, proc_ops: &scsi_scsi_proc_ops); |
558 | if (!pde) |
559 | goto err2; |
560 | |
561 | return 0; |
562 | |
563 | err2: |
564 | remove_proc_entry("scsi" , NULL); |
565 | err1: |
566 | return -ENOMEM; |
567 | } |
568 | |
569 | /** |
570 | * scsi_exit_procfs - Remove scsi/scsi and scsi from procfs |
571 | */ |
572 | void scsi_exit_procfs(void) |
573 | { |
574 | remove_proc_entry("scsi/scsi" , NULL); |
575 | remove_proc_entry("scsi" , NULL); |
576 | } |
577 | |