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1// SPDX-License-Identifier: GPL-2.02/*3 * linux/drivers/scsi/scsi_proc.c4 *5 * The functions in this file provide an interface between6 * the PROC file system and the SCSI device drivers7 * 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: 95/09/1312 * 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/* Protects scsi_proc_list */47static DEFINE_MUTEX(global_host_template_mutex);48static LIST_HEAD(scsi_proc_list);49 50/**51 * struct scsi_proc_entry - (host template, SCSI proc dir) association52 * @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 */57struct 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 64static 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(file_inode(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(page, buf, count))81 goto out;82 ret = shost->hostt->write_info(shost, page, count);83 }84out:85 free_page((unsigned long)page);86 return ret;87}88 89static 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 95static 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 101static 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 115static struct scsi_proc_entry *116scsi_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(&global_host_template_mutex);123 124 return e;125}126 127/**128 * scsi_template_proc_dir() - returns the procfs dir for a SCSI host template129 * @sht: SCSI host template pointer.130 */131struct proc_dir_entry *132scsi_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}138EXPORT_SYMBOL_GPL(scsi_template_proc_dir);139 140static 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_write146};147 148/**149 * scsi_proc_hostdir_add - Create directory in /proc for a scsi host150 * @sht: owner of this directory151 *152 * Sets sht->proc_dir to the new directory.153 */154int 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(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(&e->entry, &scsi_proc_list);182success:183 e = NULL;184 ret = 0;185unlock:186 mutex_unlock(&global_host_template_mutex);187 188 kfree(e);189 return ret;190}191 192/**193 * scsi_proc_hostdir_rm - remove directory in /proc for a scsi host194 * @sht: owner of directory195 */196void 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(&e->entry);208 kfree(e);209 }210 mutex_unlock(&global_host_template_mutex);211}212 213 214/**215 * scsi_proc_host_add - Add entry for this host to appropriate /proc dir216 * @shost: host to add217 */218void 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(name,"%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 239err: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 /proc247 * @shost: which host248 */249void 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(name,"%d", shost->host_no);263 remove_proc_entry(name, e->proc_dir);264}265/**266 * proc_print_scsidevice - return data about this host267 * @dev: A scsi device268 * @data: &struct seq_file to output to.269 *270 * Description: prints Host, Channel, Id, Lun, Vendor, Model, Rev, Type,271 * and revision.272 */273static 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(s,284 "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(s, sdev->vendor[i]);289 else290 seq_putc(s, ' ');291 }292 293 seq_puts(s, " Model: ");294 for (i = 0; i < 16; i++) {295 if (sdev->model[i] >= 0x20)296 seq_putc(s, sdev->model[i]);297 else298 seq_putc(s, ' ');299 }300 301 seq_puts(s, " Rev: ");302 for (i = 0; i < 4; i++) {303 if (sdev->rev[i] >= 0x20)304 seq_putc(s, sdev->rev[i]);305 else306 seq_putc(s, ' ');307 }308 309 seq_putc(s, '\n');310 311 seq_printf(s, " Type: %s ", scsi_device_type(sdev->type));312 seq_printf(s, " ANSI SCSI revision: %02x",313 sdev->scsi_level - (sdev->scsi_level > 1));314 if (sdev->scsi_level == 2)315 seq_puts(s, " CCS\n");316 else317 seq_putc(s, '\n');318 319out:320 return 0;321}322 323/**324 * scsi_add_single_device - Respond to user request to probe for/add device325 * @host: user-supplied decimal integer326 * @channel: user-supplied decimal integer327 * @id: user-supplied decimal integer328 * @lun: user-supplied decimal integer329 *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 transport333 * type supports it, or else scsi_scan_host_selected()334 *335 * Note: this seems to be aimed exclusively at SCSI parallel busses.336 */337 338static 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(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 else350 error = scsi_scan_host_selected(shost, channel, id, lun,351 SCSI_SCAN_MANUAL);352 scsi_host_put(shost);353 return error;354}355 356/**357 * scsi_remove_single_device - Respond to user request to remove a device358 * @host: user-supplied decimal integer359 * @channel: user-supplied decimal integer360 * @id: user-supplied decimal integer361 * @lun: user-supplied decimal integer362 *363 * Description: called by writing "scsi remove-single-device" to364 * /proc/scsi/scsi. Does a scsi_device_lookup() and scsi_remove_device()365 */366static 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(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(shost);383 return error;384}385 386/**387 * proc_scsi_write - handle writes to /proc/scsi/scsi388 * @file: not used389 * @buf: buffer to write390 * @length: length of buf, at most PAGE_SIZE391 * @ppos: not used392 *393 * Description: this provides a legacy mechanism to add or remove devices by394 * Host, Channel, ID, and Lun. To use,395 * "echo 'scsi add-single-device 0 1 2 3' > /proc/scsi/scsi" or396 * "echo 'scsi remove-single-device 0 1 2 3' > /proc/scsi/scsi" with397 * "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 to401 * provide a unique identifier and nothing more.402 */403 404 405static 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(buffer, buf, 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/scsi435 * 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/scsi449 * 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 474static inline struct device *next_scsi_device(struct device *start)475{476 struct device *next = bus_find_next_device(&scsi_bus_type, start);477 478 put_device(start);479 return next;480}481 482static 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(dev))) {488 if (!n--)489 break;490 sfile->private++;491 }492 return dev;493}494 495static void *scsi_seq_next(struct seq_file *sfile, void *v, loff_t *pos)496{497 (*pos)++;498 sfile->private++;499 return next_scsi_device(v);500}501 502static void scsi_seq_stop(struct seq_file *sfile, void *v)503{504 put_device(v);505}506 507static int scsi_seq_show(struct seq_file *sfile, void *dev)508{509 if (!sfile->private)510 seq_puts(sfile, "Attached devices:\n");511 512 return proc_print_scsidevice(dev, sfile);513}514 515static 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_show520};521 522/**523 * proc_scsi_open - glue function524 * @inode: not used525 * @file: passed to single_open()526 *527 * Associates proc_scsi_show with this file528 */529static 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't533 * harm either.534 */535 return seq_open(file, &scsi_seq_ops);536}537 538static 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 procfs548 */549int __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("scsi/scsi", 0, NULL, &scsi_scsi_proc_ops);558 if (!pde)559 goto err2;560 561 return 0;562 563err2:564 remove_proc_entry("scsi", NULL);565err1:566 return -ENOMEM;567}568 569/**570 * scsi_exit_procfs - Remove scsi/scsi and scsi from procfs571 */572void scsi_exit_procfs(void)573{574 remove_proc_entry("scsi/scsi", NULL);575 remove_proc_entry("scsi", NULL);576}577