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 /* Protect sht->present and sht->proc_dir */ 47 static DEFINE_MUTEX(global_host_template_mutex); 48 49 static 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 } 69 out: 70 free_page((unsigned long)page); 71 return ret; 72 } 73 74 static 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 80 static 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 86 static 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 */ 100 101 void 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 */ 120 void 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 */ 138 void 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 */ 160 void 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 */ 178 static 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'); 223 224 out: 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 */ 242 243 static 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 */ 271 static 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 */ 308 309 310 static 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 } 374 375 static inline struct device *next_scsi_device(struct device *start) 376 { 377 struct device *next = bus_find_next_device(&scsi_bus_type, start); 378 379 put_device(start); 380 return next; 381 } 382 383 static void *scsi_seq_start(struct seq_file *sfile, loff_t *pos) 384 { 385 struct device *dev = NULL; 386 loff_t n = *pos; 387 388 while ((dev = next_scsi_device(dev))) { 389 if (!n--) 390 break; 391 sfile->private++; 392 } 393 return dev; 394 } 395 396 static void *scsi_seq_next(struct seq_file *sfile, void *v, loff_t *pos) 397 { 398 (*pos)++; 399 sfile->private++; 400 return next_scsi_device(v); 401 } 402 403 static void scsi_seq_stop(struct seq_file *sfile, void *v) 404 { 405 put_device(v); 406 } 407 408 static int scsi_seq_show(struct seq_file *sfile, void *dev) 409 { 410 if (!sfile->private) 411 seq_puts(sfile, "Attached devices:\n"); 412 413 return proc_print_scsidevice(dev, sfile); 414 } 415 416 static const struct seq_operations scsi_seq_ops = { 417 .start = scsi_seq_start, 418 .next = scsi_seq_next, 419 .stop = scsi_seq_stop, 420 .show = scsi_seq_show 421 }; 422 423 /** 424 * proc_scsi_open - glue function 425 * @inode: not used 426 * @file: passed to single_open() 427 * 428 * Associates proc_scsi_show with this file 429 */ 430 static int proc_scsi_open(struct inode *inode, struct file *file) 431 { 432 /* 433 * We don't really need this for the write case but it doesn't 434 * harm either. 435 */ 436 return seq_open(file, &scsi_seq_ops); 437 } 438 439 static const struct file_operations proc_scsi_operations = { 440 .owner = THIS_MODULE, 441 .open = proc_scsi_open, 442 .read = seq_read, 443 .write = proc_scsi_write, 444 .llseek = seq_lseek, 445 .release = seq_release, 446 }; 447 448 /** 449 * scsi_init_procfs - create scsi and scsi/scsi in procfs 450 */ 451 int __init scsi_init_procfs(void) 452 { 453 struct proc_dir_entry *pde; 454 455 proc_scsi = proc_mkdir("scsi", NULL); 456 if (!proc_scsi) 457 goto err1; 458 459 pde = proc_create("scsi/scsi", 0, NULL, &proc_scsi_operations); 460 if (!pde) 461 goto err2; 462 463 return 0; 464 465 err2: 466 remove_proc_entry("scsi", NULL); 467 err1: 468 return -ENOMEM; 469 } 470 471 /** 472 * scsi_exit_procfs - Remove scsi/scsi and scsi from procfs 473 */ 474 void scsi_exit_procfs(void) 475 { 476 remove_proc_entry("scsi/scsi", NULL); 477 remove_proc_entry("scsi", NULL); 478 } 479