2 * osd_uld.c - OSD Upper Layer Driver
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
10 * Copyright (C) 2008 Panasas Inc. All rights reserved.
13 * Boaz Harrosh <bharrosh@panasas.com>
14 * Benny Halevy <bhalevy@panasas.com>
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
19 * Redistribution and use in source and binary forms, with or without
20 * modification, are permitted provided that the following conditions
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.
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.
45 #include <linux/namei.h>
46 #include <linux/cdev.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>
55 #include <scsi/scsi.h>
56 #include <scsi/scsi_driver.h>
57 #include <scsi/scsi_device.h>
58 #include <scsi/scsi_ioctl.h>
60 #include <scsi/osd_initiator.h>
61 #include <scsi/osd_sec.h>
63 #include "osd_debug.h"
66 # define TYPE_OSD 0x11
69 #ifndef SCSI_OSD_MAJOR
70 # define SCSI_OSD_MAJOR 260
72 #define SCSI_OSD_MAX_MINOR 64
74 static const char osd_name[] = "osd";
75 static const char *osd_version_string = "open-osd 0.2.0";
77 MODULE_AUTHOR("Boaz Harrosh <bharrosh@panasas.com>");
78 MODULE_DESCRIPTION("open-osd Upper-Layer-Driver osd.ko");
79 MODULE_LICENSE("GPL");
80 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_OSD_MAJOR);
81 MODULE_ALIAS_SCSI_DEVICE(TYPE_OSD);
83 struct osd_uld_device {
85 struct device class_dev;
88 struct osd_dev_info odi;
92 struct osd_dev_handle {
95 struct osd_uld_device *oud;
98 static DEFINE_IDA(osd_minor_ida);
100 static struct class osd_uld_class = {
101 .owner = THIS_MODULE,
106 * Char Device operations
109 static int osd_uld_open(struct inode *inode, struct file *file)
111 struct osd_uld_device *oud = container_of(inode->i_cdev,
112 struct osd_uld_device, cdev);
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);
121 static int osd_uld_release(struct inode *inode, struct file *file)
123 struct osd_uld_device *oud = file->private_data;
125 OSD_DEBUG("osd_uld_release %p\n", file->private_data);
126 file->private_data = NULL;
127 put_device(&oud->class_dev);
131 /* FIXME: Only one vector for now */
132 unsigned g_test_ioctl;
133 do_test_fn *g_do_test;
135 int osduld_register_test(unsigned ioctl, do_test_fn *do_test)
140 g_test_ioctl = ioctl;
144 EXPORT_SYMBOL(osduld_register_test);
146 void osduld_unregister_test(unsigned ioctl)
148 if (ioctl == g_test_ioctl) {
153 EXPORT_SYMBOL(osduld_unregister_test);
155 static do_test_fn *_find_ioctl(unsigned cmd)
157 if (g_test_ioctl == cmd)
163 static long osd_uld_ioctl(struct file *file, unsigned int cmd,
166 struct osd_uld_device *oud = file->private_data;
170 do_test = _find_ioctl(cmd);
172 ret = do_test(&oud->od, cmd, arg);
174 OSD_ERR("Unknown ioctl %d: osd_uld_device=%p\n", cmd, oud);
180 static 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,
188 struct osd_dev *osduld_path_lookup(const char *name)
190 struct osd_uld_device *oud;
191 struct osd_dev_handle *odh;
195 if (!name || !*name) {
196 OSD_ERR("Mount with !path || !*path\n");
197 return ERR_PTR(-EINVAL);
200 odh = kzalloc(sizeof(*odh), GFP_KERNEL);
202 return ERR_PTR(-ENOMEM);
204 file = filp_open(name, O_RDWR, 0);
206 error = PTR_ERR(file);
210 if (file->f_op != &osd_fops){
215 oud = file->private_data;
227 return ERR_PTR(error);
229 EXPORT_SYMBOL(osduld_path_lookup);
231 static inline bool _the_same_or_null(const u8 *a1, unsigned a1_len,
232 const u8 *a2, unsigned a2_len)
234 if (!a2_len) /* User string is Empty means don't care */
237 if (a1_len != a2_len)
240 return 0 == memcmp(a1, a2, a1_len);
244 const struct osd_dev_info *odi;
246 struct osd_uld_device *oud;
249 int _mach_odi(struct device *dev, void *find_data)
251 struct osd_uld_device *oud = container_of(dev, struct osd_uld_device,
253 struct find_oud_t *fot = find_data;
254 const struct osd_dev_info *odi = fot->odi;
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);
269 /* osduld_info_lookup - Loop through all devices, return the requested osd_dev.
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.
274 struct osd_dev *osduld_info_lookup(const struct osd_dev_info *odi)
276 struct find_oud_t find = {.odi = odi};
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);
282 if (unlikely(!odh)) {
283 put_device(find.dev);
284 return ERR_PTR(-ENOMEM);
287 odh->od = find.oud->od;
293 return ERR_PTR(-ENODEV);
295 EXPORT_SYMBOL(osduld_info_lookup);
297 void osduld_put_device(struct osd_dev *od)
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;
304 BUG_ON(od->scsi_device != oud->od.scsi_device);
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
313 get_device(&oud->class_dev);
316 put_device(&oud->class_dev);
320 EXPORT_SYMBOL(osduld_put_device);
322 const struct osd_dev_info *osduld_device_info(struct osd_dev *od)
324 struct osd_dev_handle *odh =
325 container_of(od, struct osd_dev_handle, od);
326 return &odh->oud->odi;
328 EXPORT_SYMBOL(osduld_device_info);
330 bool osduld_device_same(struct osd_dev *od, const struct osd_dev_info *odi)
332 struct osd_dev_handle *odh =
333 container_of(od, struct osd_dev_handle, od);
334 struct osd_uld_device *oud = odh->oud;
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);
343 EXPORT_SYMBOL(osduld_device_same);
346 * Scsi Device operations
349 static int __detect_osd(struct osd_uld_device *oud)
351 struct scsi_device *scsi_device = oud->od.scsi_device;
352 char caps[OSD_CAP_LEN];
355 /* sending a test_unit_ready as first command seems to be needed
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);
362 OSD_ERR("warning: scsi_test_unit_ready failed\n");
364 osd_sec_init_nosec_doall_caps(caps, &osd_root_object, false, true);
365 if (osd_auto_detect_ver(&oud->od, caps, &oud->odi))
371 static void __remove(struct device *dev)
373 struct osd_uld_device *oud = container_of(dev, struct osd_uld_device,
375 struct scsi_device *scsi_device = oud->od.scsi_device;
377 kfree(oud->odi.osdname);
380 cdev_del(&oud->cdev);
382 osd_dev_fini(&oud->od);
383 scsi_device_put(scsi_device);
385 OSD_INFO("osd_remove %s\n",
386 oud->disk ? oud->disk->disk_name : NULL);
390 ida_remove(&osd_minor_ida, oud->minor);
395 static int osd_probe(struct device *dev)
397 struct scsi_device *scsi_device = to_scsi_device(dev);
398 struct gendisk *disk;
399 struct osd_uld_device *oud;
403 if (scsi_device->type != TYPE_OSD)
407 if (!ida_pre_get(&osd_minor_ida, GFP_KERNEL))
410 error = ida_get_new(&osd_minor_ida, &minor);
411 } while (error == -EAGAIN);
415 if (minor >= SCSI_OSD_MAX_MINOR) {
417 goto err_retract_minor;
421 oud = kzalloc(sizeof(*oud), GFP_KERNEL);
423 goto err_retract_minor;
425 dev_set_drvdata(dev, oud);
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);
432 OSD_ERR("alloc_disk failed\n");
435 disk->major = SCSI_OSD_MAJOR;
436 disk->first_minor = oud->minor;
437 sprintf(disk->disk_name, "osd%d", oud->minor);
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
443 scsi_device_get(scsi_device);
444 osd_dev_init(&oud->od, scsi_device);
446 /* Detect the OSD Version */
447 error = __detect_osd(oud);
449 OSD_ERR("osd detection failed, non-compatible OSD device\n");
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);
459 OSD_ERR("cdev_add failed\n");
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);
470 OSD_ERR("dev_set_name failed => %d\n", error);
474 error = device_register(&oud->class_dev);
476 OSD_ERR("device_register failed => %d\n", error);
480 get_device(&oud->class_dev);
482 OSD_INFO("osd_probe %s\n", disk->disk_name);
486 cdev_del(&oud->cdev);
488 scsi_device_put(scsi_device);
491 dev_set_drvdata(dev, NULL);
494 ida_remove(&osd_minor_ida, minor);
498 static int osd_remove(struct device *dev)
500 struct scsi_device *scsi_device = to_scsi_device(dev);
501 struct osd_uld_device *oud = dev_get_drvdata(dev);
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,
509 device_unregister(&oud->class_dev);
511 put_device(&oud->class_dev);
516 * Global driver and scsi registration
519 static struct scsi_driver osd_driver = {
520 .owner = THIS_MODULE,
524 .remove = osd_remove,
528 static int __init osd_uld_init(void)
532 err = class_register(&osd_uld_class);
534 OSD_ERR("Unable to register sysfs class => %d\n", err);
538 err = register_chrdev_region(MKDEV(SCSI_OSD_MAJOR, 0),
539 SCSI_OSD_MAX_MINOR, osd_name);
541 OSD_ERR("Unable to register major %d for osd ULD => %d\n",
542 SCSI_OSD_MAJOR, err);
546 err = scsi_register_driver(&osd_driver.gendrv);
548 OSD_ERR("scsi_register_driver failed => %d\n", err);
552 OSD_INFO("LOADED %s\n", osd_version_string);
556 unregister_chrdev_region(MKDEV(SCSI_OSD_MAJOR, 0), SCSI_OSD_MAX_MINOR);
558 class_unregister(&osd_uld_class);
562 static void __exit osd_uld_exit(void)
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);
570 module_init(osd_uld_init);
571 module_exit(osd_uld_exit);