1/* 2 * osd_uld.c - OSD Upper Layer Driver 3 * 4 * A Linux driver module that registers as a SCSI ULD and probes 5 * for OSD type SCSI devices. 6 * It's main function is to export osd devices to in-kernel users like 7 * osdfs and pNFS-objects-LD. It also provides one ioctl for running 8 * in Kernel tests. 9 * 10 * Copyright (C) 2008 Panasas Inc. All rights reserved. 11 * 12 * Authors: 13 * Boaz Harrosh <bharrosh@panasas.com> 14 * Benny Halevy <bhalevy@panasas.com> 15 * 16 * This program is free software; you can redistribute it and/or modify 17 * it under the terms of the GNU General Public License version 2 18 * 19 * Redistribution and use in source and binary forms, with or without 20 * modification, are permitted provided that the following conditions 21 * are met: 22 * 23 * 1. Redistributions of source code must retain the above copyright 24 * notice, this list of conditions and the following disclaimer. 25 * 2. Redistributions in binary form must reproduce the above copyright 26 * notice, this list of conditions and the following disclaimer in the 27 * documentation and/or other materials provided with the distribution. 28 * 3. Neither the name of the Panasas company nor the names of its 29 * contributors may be used to endorse or promote products derived 30 * from this software without specific prior written permission. 31 * 32 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED 33 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 34 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 35 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 36 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 37 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 38 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 39 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 40 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 41 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 42 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 43 */ 44 45#include <linux/namei.h> 46#include <linux/cdev.h> 47#include <linux/fs.h> 48#include <linux/module.h> 49#include <linux/device.h> 50#include <linux/idr.h> 51#include <linux/major.h> 52#include <linux/file.h> 53#include <linux/slab.h> 54 55#include <scsi/scsi.h> 56#include <scsi/scsi_driver.h> 57#include <scsi/scsi_device.h> 58#include <scsi/scsi_ioctl.h> 59 60#include <scsi/osd_initiator.h> 61#include <scsi/osd_sec.h> 62 63#include "osd_debug.h" 64 65#ifndef TYPE_OSD 66# define TYPE_OSD 0x11 67#endif 68 69#ifndef SCSI_OSD_MAJOR 70# define SCSI_OSD_MAJOR 260 71#endif 72#define SCSI_OSD_MAX_MINOR MINORMASK 73 74static const char osd_name[] = "osd"; 75static const char *osd_version_string = "open-osd 0.2.1"; 76 77MODULE_AUTHOR("Boaz Harrosh <bharrosh@panasas.com>"); 78MODULE_DESCRIPTION("open-osd Upper-Layer-Driver osd.ko"); 79MODULE_LICENSE("GPL"); 80MODULE_ALIAS_CHARDEV_MAJOR(SCSI_OSD_MAJOR); 81MODULE_ALIAS_SCSI_DEVICE(TYPE_OSD); 82 83struct osd_uld_device { 84 int minor; 85 struct device class_dev; 86 struct cdev cdev; 87 struct osd_dev od; 88 struct osd_dev_info odi; 89 struct gendisk *disk; 90}; 91 92struct osd_dev_handle { 93 struct osd_dev od; 94 struct file *file; 95 struct osd_uld_device *oud; 96} ; 97 98static DEFINE_IDA(osd_minor_ida); 99 100static struct class osd_uld_class = { 101 .owner = THIS_MODULE, 102 .name = "scsi_osd", 103}; 104 105/* 106 * Char Device operations 107 */ 108 109static int osd_uld_open(struct inode *inode, struct file *file) 110{ 111 struct osd_uld_device *oud = container_of(inode->i_cdev, 112 struct osd_uld_device, cdev); 113 114 get_device(&oud->class_dev); 115 /* cache osd_uld_device on file handle */ 116 file->private_data = oud; 117 OSD_DEBUG("osd_uld_open %p\n", oud); 118 return 0; 119} 120 121static int osd_uld_release(struct inode *inode, struct file *file) 122{ 123 struct osd_uld_device *oud = file->private_data; 124 125 OSD_DEBUG("osd_uld_release %p\n", file->private_data); 126 file->private_data = NULL; 127 put_device(&oud->class_dev); 128 return 0; 129} 130 131/* FIXME: Only one vector for now */ 132unsigned g_test_ioctl; 133do_test_fn *g_do_test; 134 135int osduld_register_test(unsigned ioctl, do_test_fn *do_test) 136{ 137 if (g_test_ioctl) 138 return -EINVAL; 139 140 g_test_ioctl = ioctl; 141 g_do_test = do_test; 142 return 0; 143} 144EXPORT_SYMBOL(osduld_register_test); 145 146void osduld_unregister_test(unsigned ioctl) 147{ 148 if (ioctl == g_test_ioctl) { 149 g_test_ioctl = 0; 150 g_do_test = NULL; 151 } 152} 153EXPORT_SYMBOL(osduld_unregister_test); 154 155static do_test_fn *_find_ioctl(unsigned cmd) 156{ 157 if (g_test_ioctl == cmd) 158 return g_do_test; 159 else 160 return NULL; 161} 162 163static long osd_uld_ioctl(struct file *file, unsigned int cmd, 164 unsigned long arg) 165{ 166 struct osd_uld_device *oud = file->private_data; 167 int ret; 168 do_test_fn *do_test; 169 170 do_test = _find_ioctl(cmd); 171 if (do_test) 172 ret = do_test(&oud->od, cmd, arg); 173 else { 174 OSD_ERR("Unknown ioctl %d: osd_uld_device=%p\n", cmd, oud); 175 ret = -ENOIOCTLCMD; 176 } 177 return ret; 178} 179 180static const struct file_operations osd_fops = { 181 .owner = THIS_MODULE, 182 .open = osd_uld_open, 183 .release = osd_uld_release, 184 .unlocked_ioctl = osd_uld_ioctl, 185 .llseek = noop_llseek, 186}; 187 188struct osd_dev *osduld_path_lookup(const char *name) 189{ 190 struct osd_uld_device *oud; 191 struct osd_dev_handle *odh; 192 struct file *file; 193 int error; 194 195 if (!name || !*name) { 196 OSD_ERR("Mount with !path || !*path\n"); 197 return ERR_PTR(-EINVAL); 198 } 199 200 odh = kzalloc(sizeof(*odh), GFP_KERNEL); 201 if (unlikely(!odh)) 202 return ERR_PTR(-ENOMEM); 203 204 file = filp_open(name, O_RDWR, 0); 205 if (IS_ERR(file)) { 206 error = PTR_ERR(file); 207 goto free_od; 208 } 209 210 if (file->f_op != &osd_fops){ 211 error = -EINVAL; 212 goto close_file; 213 } 214 215 oud = file->private_data; 216 217 odh->od = oud->od; 218 odh->file = file; 219 odh->oud = oud; 220 221 return &odh->od; 222 223close_file: 224 fput(file); 225free_od: 226 kfree(odh); 227 return ERR_PTR(error); 228} 229EXPORT_SYMBOL(osduld_path_lookup); 230 231static inline bool _the_same_or_null(const u8 *a1, unsigned a1_len, 232 const u8 *a2, unsigned a2_len) 233{ 234 if (!a2_len) /* User string is Empty means don't care */ 235 return true; 236 237 if (a1_len != a2_len) 238 return false; 239 240 return 0 == memcmp(a1, a2, a1_len); 241} 242 243struct find_oud_t { 244 const struct osd_dev_info *odi; 245 struct device *dev; 246 struct osd_uld_device *oud; 247} ; 248 249int _mach_odi(struct device *dev, void *find_data) 250{ 251 struct osd_uld_device *oud = container_of(dev, struct osd_uld_device, 252 class_dev); 253 struct find_oud_t *fot = find_data; 254 const struct osd_dev_info *odi = fot->odi; 255 256 if (_the_same_or_null(oud->odi.systemid, oud->odi.systemid_len, 257 odi->systemid, odi->systemid_len) && 258 _the_same_or_null(oud->odi.osdname, oud->odi.osdname_len, 259 odi->osdname, odi->osdname_len)) { 260 OSD_DEBUG("found device sysid_len=%d osdname=%d\n", 261 odi->systemid_len, odi->osdname_len); 262 fot->oud = oud; 263 return 1; 264 } else { 265 return 0; 266 } 267} 268 269/* osduld_info_lookup - Loop through all devices, return the requested osd_dev. 270 * 271 * if @odi->systemid_len and/or @odi->osdname_len are zero, they act as a don't 272 * care. .e.g if they're both zero /dev/osd0 is returned. 273 */ 274struct osd_dev *osduld_info_lookup(const struct osd_dev_info *odi) 275{ 276 struct find_oud_t find = {.odi = odi}; 277 278 find.dev = class_find_device(&osd_uld_class, NULL, &find, _mach_odi); 279 if (likely(find.dev)) { 280 struct osd_dev_handle *odh = kzalloc(sizeof(*odh), GFP_KERNEL); 281 282 if (unlikely(!odh)) { 283 put_device(find.dev); 284 return ERR_PTR(-ENOMEM); 285 } 286 287 odh->od = find.oud->od; 288 odh->oud = find.oud; 289 290 return &odh->od; 291 } 292 293 return ERR_PTR(-ENODEV); 294} 295EXPORT_SYMBOL(osduld_info_lookup); 296 297void osduld_put_device(struct osd_dev *od) 298{ 299 if (od && !IS_ERR(od)) { 300 struct osd_dev_handle *odh = 301 container_of(od, struct osd_dev_handle, od); 302 struct osd_uld_device *oud = odh->oud; 303 304 BUG_ON(od->scsi_device != oud->od.scsi_device); 305 306 /* If scsi has released the device (logout), and exofs has last 307 * reference on oud it will be freed by above osd_uld_release 308 * within fput below. But this will oops in cdev_release which 309 * is called after the fops->release. A get_/put_ pair makes 310 * sure we have a cdev for the duration of fput 311 */ 312 if (odh->file) { 313 get_device(&oud->class_dev); 314 fput(odh->file); 315 } 316 put_device(&oud->class_dev); 317 kfree(odh); 318 } 319} 320EXPORT_SYMBOL(osduld_put_device); 321 322const struct osd_dev_info *osduld_device_info(struct osd_dev *od) 323{ 324 struct osd_dev_handle *odh = 325 container_of(od, struct osd_dev_handle, od); 326 return &odh->oud->odi; 327} 328EXPORT_SYMBOL(osduld_device_info); 329 330bool osduld_device_same(struct osd_dev *od, const struct osd_dev_info *odi) 331{ 332 struct osd_dev_handle *odh = 333 container_of(od, struct osd_dev_handle, od); 334 struct osd_uld_device *oud = odh->oud; 335 336 return (oud->odi.systemid_len == odi->systemid_len) && 337 _the_same_or_null(oud->odi.systemid, oud->odi.systemid_len, 338 odi->systemid, odi->systemid_len) && 339 (oud->odi.osdname_len == odi->osdname_len) && 340 _the_same_or_null(oud->odi.osdname, oud->odi.osdname_len, 341 odi->osdname, odi->osdname_len); 342} 343EXPORT_SYMBOL(osduld_device_same); 344 345/* 346 * Scsi Device operations 347 */ 348 349static int __detect_osd(struct osd_uld_device *oud) 350{ 351 struct scsi_device *scsi_device = oud->od.scsi_device; 352 char caps[OSD_CAP_LEN]; 353 int error; 354 355 /* sending a test_unit_ready as first command seems to be needed 356 * by some targets 357 */ 358 OSD_DEBUG("start scsi_test_unit_ready %p %p %p\n", 359 oud, scsi_device, scsi_device->request_queue); 360 error = scsi_test_unit_ready(scsi_device, 10*HZ, 5, NULL); 361 if (error) 362 OSD_ERR("warning: scsi_test_unit_ready failed\n"); 363 364 osd_sec_init_nosec_doall_caps(caps, &osd_root_object, false, true); 365 if (osd_auto_detect_ver(&oud->od, caps, &oud->odi)) 366 return -ENODEV; 367 368 return 0; 369} 370 371static void __remove(struct device *dev) 372{ 373 struct osd_uld_device *oud = container_of(dev, struct osd_uld_device, 374 class_dev); 375 struct scsi_device *scsi_device = oud->od.scsi_device; 376 377 kfree(oud->odi.osdname); 378 379 if (oud->cdev.owner) 380 cdev_del(&oud->cdev); 381 382 osd_dev_fini(&oud->od); 383 scsi_device_put(scsi_device); 384 385 OSD_INFO("osd_remove %s\n", 386 oud->disk ? oud->disk->disk_name : NULL); 387 388 if (oud->disk) 389 put_disk(oud->disk); 390 ida_remove(&osd_minor_ida, oud->minor); 391 392 kfree(oud); 393} 394 395static int osd_probe(struct device *dev) 396{ 397 struct scsi_device *scsi_device = to_scsi_device(dev); 398 struct gendisk *disk; 399 struct osd_uld_device *oud; 400 int minor; 401 int error; 402 403 if (scsi_device->type != TYPE_OSD) 404 return -ENODEV; 405 406 do { 407 if (!ida_pre_get(&osd_minor_ida, GFP_KERNEL)) 408 return -ENODEV; 409 410 error = ida_get_new(&osd_minor_ida, &minor); 411 } while (error == -EAGAIN); 412 413 if (error) 414 return error; 415 if (minor >= SCSI_OSD_MAX_MINOR) { 416 error = -EBUSY; 417 goto err_retract_minor; 418 } 419 420 error = -ENOMEM; 421 oud = kzalloc(sizeof(*oud), GFP_KERNEL); 422 if (NULL == oud) 423 goto err_retract_minor; 424 425 dev_set_drvdata(dev, oud); 426 oud->minor = minor; 427 428 /* allocate a disk and set it up */ 429 /* FIXME: do we need this since sg has already done that */ 430 disk = alloc_disk(1); 431 if (!disk) { 432 OSD_ERR("alloc_disk failed\n"); 433 goto err_free_osd; 434 } 435 disk->major = SCSI_OSD_MAJOR; 436 disk->first_minor = oud->minor; 437 sprintf(disk->disk_name, "osd%d", oud->minor); 438 oud->disk = disk; 439 440 /* hold one more reference to the scsi_device that will get released 441 * in __release, in case a logout is happening while fs is mounted 442 */ 443 scsi_device_get(scsi_device); 444 osd_dev_init(&oud->od, scsi_device); 445 446 /* Detect the OSD Version */ 447 error = __detect_osd(oud); 448 if (error) { 449 OSD_ERR("osd detection failed, non-compatible OSD device\n"); 450 goto err_put_disk; 451 } 452 453 /* init the char-device for communication with user-mode */ 454 cdev_init(&oud->cdev, &osd_fops); 455 oud->cdev.owner = THIS_MODULE; 456 error = cdev_add(&oud->cdev, 457 MKDEV(SCSI_OSD_MAJOR, oud->minor), 1); 458 if (error) { 459 OSD_ERR("cdev_add failed\n"); 460 goto err_put_disk; 461 } 462 463 /* class device member */ 464 oud->class_dev.devt = oud->cdev.dev; 465 oud->class_dev.class = &osd_uld_class; 466 oud->class_dev.parent = dev; 467 oud->class_dev.release = __remove; 468 error = dev_set_name(&oud->class_dev, disk->disk_name); 469 if (error) { 470 OSD_ERR("dev_set_name failed => %d\n", error); 471 goto err_put_cdev; 472 } 473 474 error = device_register(&oud->class_dev); 475 if (error) { 476 OSD_ERR("device_register failed => %d\n", error); 477 goto err_put_cdev; 478 } 479 480 get_device(&oud->class_dev); 481 482 OSD_INFO("osd_probe %s\n", disk->disk_name); 483 return 0; 484 485err_put_cdev: 486 cdev_del(&oud->cdev); 487err_put_disk: 488 scsi_device_put(scsi_device); 489 put_disk(disk); 490err_free_osd: 491 dev_set_drvdata(dev, NULL); 492 kfree(oud); 493err_retract_minor: 494 ida_remove(&osd_minor_ida, minor); 495 return error; 496} 497 498static int osd_remove(struct device *dev) 499{ 500 struct scsi_device *scsi_device = to_scsi_device(dev); 501 struct osd_uld_device *oud = dev_get_drvdata(dev); 502 503 if (!oud || (oud->od.scsi_device != scsi_device)) { 504 OSD_ERR("Half cooked osd-device %p,%p || %p!=%p", 505 dev, oud, oud ? oud->od.scsi_device : NULL, 506 scsi_device); 507 } 508 509 device_unregister(&oud->class_dev); 510 511 put_device(&oud->class_dev); 512 return 0; 513} 514 515/* 516 * Global driver and scsi registration 517 */ 518 519static struct scsi_driver osd_driver = { 520 .owner = THIS_MODULE, 521 .gendrv = { 522 .name = osd_name, 523 .probe = osd_probe, 524 .remove = osd_remove, 525 } 526}; 527 528static int __init osd_uld_init(void) 529{ 530 int err; 531 532 err = class_register(&osd_uld_class); 533 if (err) { 534 OSD_ERR("Unable to register sysfs class => %d\n", err); 535 return err; 536 } 537 538 err = register_chrdev_region(MKDEV(SCSI_OSD_MAJOR, 0), 539 SCSI_OSD_MAX_MINOR, osd_name); 540 if (err) { 541 OSD_ERR("Unable to register major %d for osd ULD => %d\n", 542 SCSI_OSD_MAJOR, err); 543 goto err_out; 544 } 545 546 err = scsi_register_driver(&osd_driver.gendrv); 547 if (err) { 548 OSD_ERR("scsi_register_driver failed => %d\n", err); 549 goto err_out_chrdev; 550 } 551 552 OSD_INFO("LOADED %s\n", osd_version_string); 553 return 0; 554 555err_out_chrdev: 556 unregister_chrdev_region(MKDEV(SCSI_OSD_MAJOR, 0), SCSI_OSD_MAX_MINOR); 557err_out: 558 class_unregister(&osd_uld_class); 559 return err; 560} 561 562static void __exit osd_uld_exit(void) 563{ 564 scsi_unregister_driver(&osd_driver.gendrv); 565 unregister_chrdev_region(MKDEV(SCSI_OSD_MAJOR, 0), SCSI_OSD_MAX_MINOR); 566 class_unregister(&osd_uld_class); 567 OSD_INFO("UNLOADED %s\n", osd_version_string); 568} 569 570module_init(osd_uld_init); 571module_exit(osd_uld_exit); 572