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
44static struct proc_dir_entry *proc_scsi;
45
46/* Protect sht->present and sht->proc_dir */
47static DEFINE_MUTEX(global_host_template_mutex);
48
49static ssize_t proc_scsi_host_write(struct file *file, const char __user *buf,
50 size_t count, loff_t *ppos)
51{
52 struct Scsi_Host *shost = PDE_DATA(file_inode(file));
53 ssize_t ret = -ENOMEM;
54 char *page;
55
56 if (count > PROC_BLOCK_SIZE)
57 return -EOVERFLOW;
58
59 if (!shost->hostt->write_info)
60 return -EINVAL;
61
62 page = (char *)__get_free_page(GFP_KERNEL);
63 if (page) {
64 ret = -EFAULT;
65 if (copy_from_user(page, buf, count))
66 goto out;
67 ret = shost->hostt->write_info(shost, page, count);
68 }
69out:
70 free_page((unsigned long)page);
71 return ret;
72}
73
74static int proc_scsi_show(struct seq_file *m, void *v)
75{
76 struct Scsi_Host *shost = m->private;
77 return shost->hostt->show_info(m, shost);
78}
79
80static int proc_scsi_host_open(struct inode *inode, struct file *file)
81{
82 return single_open_size(file, proc_scsi_show, PDE_DATA(inode),
83 4 * PAGE_SIZE);
84}
85
86static const struct file_operations proc_scsi_fops = {
87 .open = proc_scsi_host_open,
88 .release = single_release,
89 .read = seq_read,
90 .llseek = seq_lseek,
91 .write = proc_scsi_host_write
92};
93
94/**
95 * scsi_proc_hostdir_add - Create directory in /proc for a scsi host
96 * @sht: owner of this directory
97 *
98 * Sets sht->proc_dir to the new directory.
99 */
100
101void scsi_proc_hostdir_add(struct scsi_host_template *sht)
102{
103 if (!sht->show_info)
104 return;
105
106 mutex_lock(&global_host_template_mutex);
107 if (!sht->present++) {
108 sht->proc_dir = proc_mkdir(sht->proc_name, proc_scsi);
109 if (!sht->proc_dir)
110 printk(KERN_ERR "%s: proc_mkdir failed for %s\n",
111 __func__, sht->proc_name);
112 }
113 mutex_unlock(&global_host_template_mutex);
114}
115
116/**
117 * scsi_proc_hostdir_rm - remove directory in /proc for a scsi host
118 * @sht: owner of directory
119 */
120void scsi_proc_hostdir_rm(struct scsi_host_template *sht)
121{
122 if (!sht->show_info)
123 return;
124
125 mutex_lock(&global_host_template_mutex);
126 if (!--sht->present && sht->proc_dir) {
127 remove_proc_entry(sht->proc_name, proc_scsi);
128 sht->proc_dir = NULL;
129 }
130 mutex_unlock(&global_host_template_mutex);
131}
132
133
134/**
135 * scsi_proc_host_add - Add entry for this host to appropriate /proc dir
136 * @shost: host to add
137 */
138void scsi_proc_host_add(struct Scsi_Host *shost)
139{
140 struct scsi_host_template *sht = shost->hostt;
141 struct proc_dir_entry *p;
142 char name[10];
143
144 if (!sht->proc_dir)
145 return;
146
147 sprintf(name,"%d", shost->host_no);
148 p = proc_create_data(name, S_IRUGO | S_IWUSR,
149 sht->proc_dir, &proc_scsi_fops, shost);
150 if (!p)
151 printk(KERN_ERR "%s: Failed to register host %d in"
152 "%s\n", __func__, shost->host_no,
153 sht->proc_name);
154}
155
156/**
157 * scsi_proc_host_rm - remove this host's entry from /proc
158 * @shost: which host
159 */
160void scsi_proc_host_rm(struct Scsi_Host *shost)
161{
162 char name[10];
163
164 if (!shost->hostt->proc_dir)
165 return;
166
167 sprintf(name,"%d", shost->host_no);
168 remove_proc_entry(name, shost->hostt->proc_dir);
169}
170/**
171 * proc_print_scsidevice - return data about this host
172 * @dev: A scsi device
173 * @data: &struct seq_file to output to.
174 *
175 * Description: prints Host, Channel, Id, Lun, Vendor, Model, Rev, Type,
176 * and revision.
177 */
178static int proc_print_scsidevice(struct device *dev, void *data)
179{
180 struct scsi_device *sdev;
181 struct seq_file *s = data;
182 int i;
183
184 if (!scsi_is_sdev_device(dev))
185 goto out;
186
187 sdev = to_scsi_device(dev);
188 seq_printf(s,
189 "Host: scsi%d Channel: %02d Id: %02d Lun: %02llu\n Vendor: ",
190 sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
191 for (i = 0; i < 8; i++) {
192 if (sdev->vendor[i] >= 0x20)
193 seq_putc(s, sdev->vendor[i]);
194 else
195 seq_putc(s, ' ');
196 }
197
198 seq_puts(s, " Model: ");
199 for (i = 0; i < 16; i++) {
200 if (sdev->model[i] >= 0x20)
201 seq_putc(s, sdev->model[i]);
202 else
203 seq_putc(s, ' ');
204 }
205
206 seq_puts(s, " Rev: ");
207 for (i = 0; i < 4; i++) {
208 if (sdev->rev[i] >= 0x20)
209 seq_putc(s, sdev->rev[i]);
210 else
211 seq_putc(s, ' ');
212 }
213
214 seq_putc(s, '\n');
215
216 seq_printf(s, " Type: %s ", scsi_device_type(sdev->type));
217 seq_printf(s, " ANSI SCSI revision: %02x",
218 sdev->scsi_level - (sdev->scsi_level > 1));
219 if (sdev->scsi_level == 2)
220 seq_puts(s, " CCS\n");
221 else
222 seq_putc(s, '\n');
223
224out:
225 return 0;
226}
227
228/**
229 * scsi_add_single_device - Respond to user request to probe for/add device
230 * @host: user-supplied decimal integer
231 * @channel: user-supplied decimal integer
232 * @id: user-supplied decimal integer
233 * @lun: user-supplied decimal integer
234 *
235 * Description: called by writing "scsi add-single-device" to /proc/scsi/scsi.
236 *
237 * does scsi_host_lookup() and either user_scan() if that transport
238 * type supports it, or else scsi_scan_host_selected()
239 *
240 * Note: this seems to be aimed exclusively at SCSI parallel busses.
241 */
242
243static int scsi_add_single_device(uint host, uint channel, uint id, uint lun)
244{
245 struct Scsi_Host *shost;
246 int error = -ENXIO;
247
248 shost = scsi_host_lookup(host);
249 if (!shost)
250 return error;
251
252 if (shost->transportt->user_scan)
253 error = shost->transportt->user_scan(shost, channel, id, lun);
254 else
255 error = scsi_scan_host_selected(shost, channel, id, lun,
256 SCSI_SCAN_MANUAL);
257 scsi_host_put(shost);
258 return error;
259}
260
261/**
262 * scsi_remove_single_device - Respond to user request to remove a device
263 * @host: user-supplied decimal integer
264 * @channel: user-supplied decimal integer
265 * @id: user-supplied decimal integer
266 * @lun: user-supplied decimal integer
267 *
268 * Description: called by writing "scsi remove-single-device" to
269 * /proc/scsi/scsi. Does a scsi_device_lookup() and scsi_remove_device()
270 */
271static int scsi_remove_single_device(uint host, uint channel, uint id, uint lun)
272{
273 struct scsi_device *sdev;
274 struct Scsi_Host *shost;
275 int error = -ENXIO;
276
277 shost = scsi_host_lookup(host);
278 if (!shost)
279 return error;
280 sdev = scsi_device_lookup(shost, channel, id, lun);
281 if (sdev) {
282 scsi_remove_device(sdev);
283 scsi_device_put(sdev);
284 error = 0;
285 }
286
287 scsi_host_put(shost);
288 return error;
289}
290
291/**
292 * proc_scsi_write - handle writes to /proc/scsi/scsi
293 * @file: not used
294 * @buf: buffer to write
295 * @length: length of buf, at most PAGE_SIZE
296 * @ppos: not used
297 *
298 * Description: this provides a legacy mechanism to add or remove devices by
299 * Host, Channel, ID, and Lun. To use,
300 * "echo 'scsi add-single-device 0 1 2 3' > /proc/scsi/scsi" or
301 * "echo 'scsi remove-single-device 0 1 2 3' > /proc/scsi/scsi" with
302 * "0 1 2 3" replaced by the Host, Channel, Id, and Lun.
303 *
304 * Note: this seems to be aimed at parallel SCSI. Most modern busses (USB,
305 * SATA, Firewire, Fibre Channel, etc) dynamically assign these values to
306 * provide a unique identifier and nothing more.
307 */
308
309
310static ssize_t proc_scsi_write(struct file *file, const char __user *buf,
311 size_t length, loff_t *ppos)
312{
313 int host, channel, id, lun;
314 char *buffer, *p;
315 int err;
316
317 if (!buf || length > PAGE_SIZE)
318 return -EINVAL;
319
320 buffer = (char *)__get_free_page(GFP_KERNEL);
321 if (!buffer)
322 return -ENOMEM;
323
324 err = -EFAULT;
325 if (copy_from_user(buffer, buf, length))
326 goto out;
327
328 err = -EINVAL;
329 if (length < PAGE_SIZE)
330 buffer[length] = '\0';
331 else if (buffer[PAGE_SIZE-1])
332 goto out;
333
334 /*
335 * Usage: echo "scsi add-single-device 0 1 2 3" >/proc/scsi/scsi
336 * with "0 1 2 3" replaced by your "Host Channel Id Lun".
337 */
338 if (!strncmp("scsi add-single-device", buffer, 22)) {
339 p = buffer + 23;
340
341 host = simple_strtoul(p, &p, 0);
342 channel = simple_strtoul(p + 1, &p, 0);
343 id = simple_strtoul(p + 1, &p, 0);
344 lun = simple_strtoul(p + 1, &p, 0);
345
346 err = scsi_add_single_device(host, channel, id, lun);
347
348 /*
349 * Usage: echo "scsi remove-single-device 0 1 2 3" >/proc/scsi/scsi
350 * with "0 1 2 3" replaced by your "Host Channel Id Lun".
351 */
352 } else if (!strncmp("scsi remove-single-device", buffer, 25)) {
353 p = buffer + 26;
354
355 host = simple_strtoul(p, &p, 0);
356 channel = simple_strtoul(p + 1, &p, 0);
357 id = simple_strtoul(p + 1, &p, 0);
358 lun = simple_strtoul(p + 1, &p, 0);
359
360 err = scsi_remove_single_device(host, channel, id, lun);
361 }
362
363 /*
364 * convert success returns so that we return the
365 * number of bytes consumed.
366 */
367 if (!err)
368 err = length;
369
370 out:
371 free_page((unsigned long)buffer);
372 return err;
373}
374
375static int always_match(struct device *dev, void *data)
376{
377 return 1;
378}
379
380static inline struct device *next_scsi_device(struct device *start)
381{
382 struct device *next = bus_find_device(&scsi_bus_type, start, NULL,
383 always_match);
384 put_device(start);
385 return next;
386}
387
388static void *scsi_seq_start(struct seq_file *sfile, loff_t *pos)
389{
390 struct device *dev = NULL;
391 loff_t n = *pos;
392
393 while ((dev = next_scsi_device(dev))) {
394 if (!n--)
395 break;
396 sfile->private++;
397 }
398 return dev;
399}
400
401static void *scsi_seq_next(struct seq_file *sfile, void *v, loff_t *pos)
402{
403 (*pos)++;
404 sfile->private++;
405 return next_scsi_device(v);
406}
407
408static void scsi_seq_stop(struct seq_file *sfile, void *v)
409{
410 put_device(v);
411}
412
413static int scsi_seq_show(struct seq_file *sfile, void *dev)
414{
415 if (!sfile->private)
416 seq_puts(sfile, "Attached devices:\n");
417
418 return proc_print_scsidevice(dev, sfile);
419}
420
421static const struct seq_operations scsi_seq_ops = {
422 .start = scsi_seq_start,
423 .next = scsi_seq_next,
424 .stop = scsi_seq_stop,
425 .show = scsi_seq_show
426};
427
428/**
429 * proc_scsi_open - glue function
430 * @inode: not used
431 * @file: passed to single_open()
432 *
433 * Associates proc_scsi_show with this file
434 */
435static int proc_scsi_open(struct inode *inode, struct file *file)
436{
437 /*
438 * We don't really need this for the write case but it doesn't
439 * harm either.
440 */
441 return seq_open(file, &scsi_seq_ops);
442}
443
444static const struct file_operations proc_scsi_operations = {
445 .owner = THIS_MODULE,
446 .open = proc_scsi_open,
447 .read = seq_read,
448 .write = proc_scsi_write,
449 .llseek = seq_lseek,
450 .release = seq_release,
451};
452
453/**
454 * scsi_init_procfs - create scsi and scsi/scsi in procfs
455 */
456int __init scsi_init_procfs(void)
457{
458 struct proc_dir_entry *pde;
459
460 proc_scsi = proc_mkdir("scsi", NULL);
461 if (!proc_scsi)
462 goto err1;
463
464 pde = proc_create("scsi/scsi", 0, NULL, &proc_scsi_operations);
465 if (!pde)
466 goto err2;
467
468 return 0;
469
470err2:
471 remove_proc_entry("scsi", NULL);
472err1:
473 return -ENOMEM;
474}
475
476/**
477 * scsi_exit_procfs - Remove scsi/scsi and scsi from procfs
478 */
479void scsi_exit_procfs(void)
480{
481 remove_proc_entry("scsi/scsi", NULL);
482 remove_proc_entry("scsi", NULL);
483}
484