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Jens Axboe3d6392c2007-07-09 12:38:05 +02001/*
2 * bsg.c - block layer implementation of the sg v3 interface
3 *
4 * Copyright (C) 2004 Jens Axboe <axboe@suse.de> SUSE Labs
5 * Copyright (C) 2004 Peter M. Jones <pjones@redhat.com>
6 *
7 * This file is subject to the terms and conditions of the GNU General Public
8 * License version 2. See the file "COPYING" in the main directory of this
9 * archive for more details.
10 *
11 */
12/*
13 * TODO
14 * - Should this get merged, block/scsi_ioctl.c will be migrated into
15 * this file. To keep maintenance down, it's easier to have them
16 * seperated right now.
17 *
18 */
Jens Axboe3d6392c2007-07-09 12:38:05 +020019#include <linux/module.h>
20#include <linux/init.h>
21#include <linux/file.h>
22#include <linux/blkdev.h>
23#include <linux/poll.h>
24#include <linux/cdev.h>
25#include <linux/percpu.h>
26#include <linux/uio.h>
27#include <linux/bsg.h>
28
29#include <scsi/scsi.h>
30#include <scsi/scsi_ioctl.h>
31#include <scsi/scsi_cmnd.h>
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +020032#include <scsi/scsi_device.h>
33#include <scsi/scsi_driver.h>
Jens Axboe3d6392c2007-07-09 12:38:05 +020034#include <scsi/sg.h>
35
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +020036#define BSG_DESCRIPTION "Block layer SCSI generic (bsg) driver"
37#define BSG_VERSION "0.4"
Jens Axboe3d6392c2007-07-09 12:38:05 +020038
Jens Axboe3d6392c2007-07-09 12:38:05 +020039struct bsg_device {
Jens Axboe3d6392c2007-07-09 12:38:05 +020040 request_queue_t *queue;
41 spinlock_t lock;
42 struct list_head busy_list;
43 struct list_head done_list;
44 struct hlist_node dev_list;
45 atomic_t ref_count;
46 int minor;
47 int queued_cmds;
48 int done_cmds;
Jens Axboe3d6392c2007-07-09 12:38:05 +020049 wait_queue_head_t wq_done;
50 wait_queue_head_t wq_free;
FUJITA Tomonorid351af02007-07-09 12:40:35 +020051 char name[BUS_ID_SIZE];
Jens Axboe3d6392c2007-07-09 12:38:05 +020052 int max_queue;
53 unsigned long flags;
54};
55
56enum {
57 BSG_F_BLOCK = 1,
58 BSG_F_WRITE_PERM = 2,
59};
60
Jens Axboe5309cb32007-01-23 16:24:41 +010061#define BSG_DEFAULT_CMDS 64
FUJITA Tomonori292b7f22007-03-28 13:29:58 +020062#define BSG_MAX_DEVS 32768
Jens Axboe3d6392c2007-07-09 12:38:05 +020063
64#undef BSG_DEBUG
65
66#ifdef BSG_DEBUG
67#define dprintk(fmt, args...) printk(KERN_ERR "%s: " fmt, __FUNCTION__, ##args)
68#else
69#define dprintk(fmt, args...)
70#endif
71
Jens Axboe3d6392c2007-07-09 12:38:05 +020072static DEFINE_MUTEX(bsg_mutex);
FUJITA Tomonori292b7f22007-03-28 13:29:58 +020073static int bsg_device_nr, bsg_minor_idx;
Jens Axboe3d6392c2007-07-09 12:38:05 +020074
Jens Axboe25fd1642007-07-17 08:52:29 +020075#define BSG_LIST_ARRAY_SIZE 8
Jens Axboe25fd1642007-07-17 08:52:29 +020076static struct hlist_head bsg_device_list[BSG_LIST_ARRAY_SIZE];
Jens Axboe3d6392c2007-07-09 12:38:05 +020077
78static struct class *bsg_class;
79static LIST_HEAD(bsg_class_list);
Jens Axboe46f6ef42007-07-17 08:56:10 +020080static int bsg_major;
Jens Axboe3d6392c2007-07-09 12:38:05 +020081
Jens Axboe5309cb32007-01-23 16:24:41 +010082static struct kmem_cache *bsg_cmd_cachep;
83
Jens Axboe3d6392c2007-07-09 12:38:05 +020084/*
85 * our internal command type
86 */
87struct bsg_command {
88 struct bsg_device *bd;
89 struct list_head list;
90 struct request *rq;
91 struct bio *bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +020092 struct bio *bidi_bio;
Jens Axboe3d6392c2007-07-09 12:38:05 +020093 int err;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +010094 struct sg_io_v4 hdr;
95 struct sg_io_v4 __user *uhdr;
Jens Axboe3d6392c2007-07-09 12:38:05 +020096 char sense[SCSI_SENSE_BUFFERSIZE];
97};
98
99static void bsg_free_command(struct bsg_command *bc)
100{
101 struct bsg_device *bd = bc->bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200102 unsigned long flags;
103
Jens Axboe5309cb32007-01-23 16:24:41 +0100104 kmem_cache_free(bsg_cmd_cachep, bc);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200105
106 spin_lock_irqsave(&bd->lock, flags);
107 bd->queued_cmds--;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200108 spin_unlock_irqrestore(&bd->lock, flags);
109
110 wake_up(&bd->wq_free);
111}
112
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200113static struct bsg_command *bsg_alloc_command(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200114{
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200115 struct bsg_command *bc = ERR_PTR(-EINVAL);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200116
117 spin_lock_irq(&bd->lock);
118
119 if (bd->queued_cmds >= bd->max_queue)
120 goto out;
121
Jens Axboe3d6392c2007-07-09 12:38:05 +0200122 bd->queued_cmds++;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200123 spin_unlock_irq(&bd->lock);
124
Jens Axboe25fd1642007-07-17 08:52:29 +0200125 bc = kmem_cache_zalloc(bsg_cmd_cachep, GFP_KERNEL);
Jens Axboe5309cb32007-01-23 16:24:41 +0100126 if (unlikely(!bc)) {
127 spin_lock_irq(&bd->lock);
FUJITA Tomonori7e75d732007-01-24 09:05:54 +0100128 bd->queued_cmds--;
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200129 bc = ERR_PTR(-ENOMEM);
FUJITA Tomonori7e75d732007-01-24 09:05:54 +0100130 goto out;
Jens Axboe5309cb32007-01-23 16:24:41 +0100131 }
132
Jens Axboe3d6392c2007-07-09 12:38:05 +0200133 bc->bd = bd;
134 INIT_LIST_HEAD(&bc->list);
Jens Axboe5309cb32007-01-23 16:24:41 +0100135 dprintk("%s: returning free cmd %p\n", bd->name, bc);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200136 return bc;
137out:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200138 spin_unlock_irq(&bd->lock);
139 return bc;
140}
141
FUJITA Tomonori1c1133e2007-07-17 12:21:15 +0200142static inline struct hlist_head *bsg_dev_idx_hash(int index)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200143{
FUJITA Tomonori1c1133e2007-07-17 12:21:15 +0200144 return &bsg_device_list[index & (BSG_LIST_ARRAY_SIZE - 1)];
Jens Axboe3d6392c2007-07-09 12:38:05 +0200145}
146
Jens Axboe25fd1642007-07-17 08:52:29 +0200147static int bsg_io_schedule(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200148{
149 DEFINE_WAIT(wait);
150 int ret = 0;
151
152 spin_lock_irq(&bd->lock);
153
154 BUG_ON(bd->done_cmds > bd->queued_cmds);
155
156 /*
157 * -ENOSPC or -ENODATA? I'm going for -ENODATA, meaning "I have no
158 * work to do", even though we return -ENOSPC after this same test
159 * during bsg_write() -- there, it means our buffer can't have more
160 * bsg_commands added to it, thus has no space left.
161 */
162 if (bd->done_cmds == bd->queued_cmds) {
163 ret = -ENODATA;
164 goto unlock;
165 }
166
167 if (!test_bit(BSG_F_BLOCK, &bd->flags)) {
168 ret = -EAGAIN;
169 goto unlock;
170 }
171
Jens Axboe25fd1642007-07-17 08:52:29 +0200172 prepare_to_wait(&bd->wq_done, &wait, TASK_UNINTERRUPTIBLE);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200173 spin_unlock_irq(&bd->lock);
174 io_schedule();
175 finish_wait(&bd->wq_done, &wait);
176
Jens Axboe3d6392c2007-07-09 12:38:05 +0200177 return ret;
178unlock:
179 spin_unlock_irq(&bd->lock);
180 return ret;
181}
182
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100183static int blk_fill_sgv4_hdr_rq(request_queue_t *q, struct request *rq,
184 struct sg_io_v4 *hdr, int has_write_perm)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200185{
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100186 memset(rq->cmd, 0, BLK_MAX_CDB); /* ATAPI hates garbage after CDB */
187
188 if (copy_from_user(rq->cmd, (void *)(unsigned long)hdr->request,
189 hdr->request_len))
190 return -EFAULT;
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200191
192 if (hdr->subprotocol == BSG_SUB_PROTOCOL_SCSI_CMD) {
193 if (blk_verify_command(rq->cmd, has_write_perm))
194 return -EPERM;
195 } else if (!capable(CAP_SYS_RAWIO))
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100196 return -EPERM;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200197
198 /*
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100199 * fill in request structure
Jens Axboe3d6392c2007-07-09 12:38:05 +0200200 */
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100201 rq->cmd_len = hdr->request_len;
202 rq->cmd_type = REQ_TYPE_BLOCK_PC;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200203
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100204 rq->timeout = (hdr->timeout * HZ) / 1000;
205 if (!rq->timeout)
206 rq->timeout = q->sg_timeout;
207 if (!rq->timeout)
208 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200209
210 return 0;
211}
212
213/*
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100214 * Check if sg_io_v4 from user is allowed and valid
215 */
216static int
217bsg_validate_sgv4_hdr(request_queue_t *q, struct sg_io_v4 *hdr, int *rw)
218{
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200219 int ret = 0;
220
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100221 if (hdr->guard != 'Q')
222 return -EINVAL;
223 if (hdr->request_len > BLK_MAX_CDB)
224 return -EINVAL;
225 if (hdr->dout_xfer_len > (q->max_sectors << 9) ||
226 hdr->din_xfer_len > (q->max_sectors << 9))
227 return -EIO;
228
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200229 switch (hdr->protocol) {
230 case BSG_PROTOCOL_SCSI:
231 switch (hdr->subprotocol) {
232 case BSG_SUB_PROTOCOL_SCSI_CMD:
233 case BSG_SUB_PROTOCOL_SCSI_TRANSPORT:
234 break;
235 default:
236 ret = -EINVAL;
237 }
238 break;
239 default:
240 ret = -EINVAL;
241 }
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100242
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100243 *rw = hdr->dout_xfer_len ? WRITE : READ;
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200244 return ret;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100245}
246
247/*
248 * map sg_io_v4 to a request.
Jens Axboe3d6392c2007-07-09 12:38:05 +0200249 */
250static struct request *
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100251bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200252{
253 request_queue_t *q = bd->queue;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200254 struct request *rq, *next_rq = NULL;
Jens Axboe25fd1642007-07-17 08:52:29 +0200255 int ret, rw;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100256 unsigned int dxfer_len;
257 void *dxferp = NULL;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200258
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100259 dprintk("map hdr %llx/%u %llx/%u\n", (unsigned long long) hdr->dout_xferp,
260 hdr->dout_xfer_len, (unsigned long long) hdr->din_xferp,
261 hdr->din_xfer_len);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200262
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100263 ret = bsg_validate_sgv4_hdr(q, hdr, &rw);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200264 if (ret)
265 return ERR_PTR(ret);
266
267 /*
268 * map scatter-gather elements seperately and string them to request
269 */
270 rq = blk_get_request(q, rw, GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200271 if (!rq)
272 return ERR_PTR(-ENOMEM);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100273 ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, test_bit(BSG_F_WRITE_PERM,
274 &bd->flags));
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200275 if (ret)
276 goto out;
277
278 if (rw == WRITE && hdr->din_xfer_len) {
279 if (!test_bit(QUEUE_FLAG_BIDI, &q->queue_flags)) {
280 ret = -EOPNOTSUPP;
281 goto out;
282 }
283
284 next_rq = blk_get_request(q, READ, GFP_KERNEL);
285 if (!next_rq) {
286 ret = -ENOMEM;
287 goto out;
288 }
289 rq->next_rq = next_rq;
290
291 dxferp = (void*)(unsigned long)hdr->din_xferp;
292 ret = blk_rq_map_user(q, next_rq, dxferp, hdr->din_xfer_len);
293 if (ret)
294 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200295 }
296
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100297 if (hdr->dout_xfer_len) {
298 dxfer_len = hdr->dout_xfer_len;
299 dxferp = (void*)(unsigned long)hdr->dout_xferp;
300 } else if (hdr->din_xfer_len) {
301 dxfer_len = hdr->din_xfer_len;
302 dxferp = (void*)(unsigned long)hdr->din_xferp;
303 } else
304 dxfer_len = 0;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200305
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100306 if (dxfer_len) {
307 ret = blk_rq_map_user(q, rq, dxferp, dxfer_len);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200308 if (ret)
309 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200310 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200311 return rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200312out:
313 blk_put_request(rq);
314 if (next_rq) {
315 blk_rq_unmap_user(next_rq->bio);
316 blk_put_request(next_rq);
317 }
318 return ERR_PTR(ret);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200319}
320
321/*
322 * async completion call-back from the block layer, when scsi/ide/whatever
323 * calls end_that_request_last() on a request
324 */
325static void bsg_rq_end_io(struct request *rq, int uptodate)
326{
327 struct bsg_command *bc = rq->end_io_data;
328 struct bsg_device *bd = bc->bd;
329 unsigned long flags;
330
Jens Axboe5309cb32007-01-23 16:24:41 +0100331 dprintk("%s: finished rq %p bc %p, bio %p stat %d\n",
332 bd->name, rq, bc, bc->bio, uptodate);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200333
334 bc->hdr.duration = jiffies_to_msecs(jiffies - bc->hdr.duration);
335
336 spin_lock_irqsave(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200337 list_move_tail(&bc->list, &bd->done_list);
338 bd->done_cmds++;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200339 spin_unlock_irqrestore(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200340
341 wake_up(&bd->wq_done);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200342}
343
344/*
345 * do final setup of a 'bc' and submit the matching 'rq' to the block
346 * layer for io
347 */
348static void bsg_add_command(struct bsg_device *bd, request_queue_t *q,
349 struct bsg_command *bc, struct request *rq)
350{
351 rq->sense = bc->sense;
352 rq->sense_len = 0;
353
354 /*
355 * add bc command to busy queue and submit rq for io
356 */
357 bc->rq = rq;
358 bc->bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200359 if (rq->next_rq)
360 bc->bidi_bio = rq->next_rq->bio;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200361 bc->hdr.duration = jiffies;
362 spin_lock_irq(&bd->lock);
363 list_add_tail(&bc->list, &bd->busy_list);
364 spin_unlock_irq(&bd->lock);
365
366 dprintk("%s: queueing rq %p, bc %p\n", bd->name, rq, bc);
367
368 rq->end_io_data = bc;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200369 blk_execute_rq_nowait(q, NULL, rq, 1, bsg_rq_end_io);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200370}
371
Jens Axboe25fd1642007-07-17 08:52:29 +0200372static struct bsg_command *bsg_next_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200373{
374 struct bsg_command *bc = NULL;
375
376 spin_lock_irq(&bd->lock);
377 if (bd->done_cmds) {
Jens Axboe25fd1642007-07-17 08:52:29 +0200378 bc = list_entry(bd->done_list.next, struct bsg_command, list);
379 list_del(&bc->list);
380 bd->done_cmds--;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200381 }
382 spin_unlock_irq(&bd->lock);
383
384 return bc;
385}
386
387/*
388 * Get a finished command from the done list
389 */
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200390static struct bsg_command *bsg_get_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200391{
392 struct bsg_command *bc;
393 int ret;
394
395 do {
396 bc = bsg_next_done_cmd(bd);
397 if (bc)
398 break;
399
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200400 if (!test_bit(BSG_F_BLOCK, &bd->flags)) {
401 bc = ERR_PTR(-EAGAIN);
402 break;
403 }
404
405 ret = wait_event_interruptible(bd->wq_done, bd->done_cmds);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200406 if (ret) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200407 bc = ERR_PTR(-ERESTARTSYS);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200408 break;
409 }
410 } while (1);
411
412 dprintk("%s: returning done %p\n", bd->name, bc);
413
414 return bc;
415}
416
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100417static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr,
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200418 struct bio *bio, struct bio *bidi_bio)
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100419{
420 int ret = 0;
421
422 dprintk("rq %p bio %p %u\n", rq, bio, rq->errors);
423 /*
424 * fill in all the output members
425 */
426 hdr->device_status = status_byte(rq->errors);
427 hdr->transport_status = host_byte(rq->errors);
428 hdr->driver_status = driver_byte(rq->errors);
429 hdr->info = 0;
430 if (hdr->device_status || hdr->transport_status || hdr->driver_status)
431 hdr->info |= SG_INFO_CHECK;
432 hdr->din_resid = rq->data_len;
433 hdr->response_len = 0;
434
435 if (rq->sense_len && hdr->response) {
Jens Axboe25fd1642007-07-17 08:52:29 +0200436 int len = min_t(unsigned int, hdr->max_response_len,
437 rq->sense_len);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100438
439 ret = copy_to_user((void*)(unsigned long)hdr->response,
440 rq->sense, len);
441 if (!ret)
442 hdr->response_len = len;
443 else
444 ret = -EFAULT;
445 }
446
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200447 if (rq->next_rq) {
448 blk_rq_unmap_user(bidi_bio);
449 blk_put_request(rq->next_rq);
450 }
451
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100452 blk_rq_unmap_user(bio);
453 blk_put_request(rq);
454
455 return ret;
456}
457
Jens Axboe3d6392c2007-07-09 12:38:05 +0200458static int bsg_complete_all_commands(struct bsg_device *bd)
459{
460 struct bsg_command *bc;
461 int ret, tret;
462
463 dprintk("%s: entered\n", bd->name);
464
465 set_bit(BSG_F_BLOCK, &bd->flags);
466
467 /*
468 * wait for all commands to complete
469 */
470 ret = 0;
471 do {
Jens Axboe25fd1642007-07-17 08:52:29 +0200472 ret = bsg_io_schedule(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200473 /*
474 * look for -ENODATA specifically -- we'll sometimes get
475 * -ERESTARTSYS when we've taken a signal, but we can't
476 * return until we're done freeing the queue, so ignore
477 * it. The signal will get handled when we're done freeing
478 * the bsg_device.
479 */
480 } while (ret != -ENODATA);
481
482 /*
483 * discard done commands
484 */
485 ret = 0;
486 do {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200487 spin_lock_irq(&bd->lock);
488 if (!bd->queued_cmds) {
489 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200490 break;
491 }
FUJITA Tomonoriefba1a32007-06-07 13:24:06 +0200492 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200493
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200494 bc = bsg_get_done_cmd(bd);
495 if (IS_ERR(bc))
496 break;
497
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200498 tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
499 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200500 if (!ret)
501 ret = tret;
502
503 bsg_free_command(bc);
504 } while (1);
505
506 return ret;
507}
508
Jens Axboe25fd1642007-07-17 08:52:29 +0200509static int
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200510__bsg_read(char __user *buf, size_t count, struct bsg_device *bd,
511 const struct iovec *iov, ssize_t *bytes_read)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200512{
513 struct bsg_command *bc;
514 int nr_commands, ret;
515
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100516 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200517 return -EINVAL;
518
519 ret = 0;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100520 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200521 while (nr_commands) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200522 bc = bsg_get_done_cmd(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200523 if (IS_ERR(bc)) {
524 ret = PTR_ERR(bc);
525 break;
526 }
527
528 /*
529 * this is the only case where we need to copy data back
530 * after completing the request. so do that here,
531 * bsg_complete_work() cannot do that for us
532 */
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200533 ret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
534 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200535
Jens Axboe25fd1642007-07-17 08:52:29 +0200536 if (copy_to_user(buf, &bc->hdr, sizeof(bc->hdr)))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200537 ret = -EFAULT;
538
539 bsg_free_command(bc);
540
541 if (ret)
542 break;
543
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100544 buf += sizeof(struct sg_io_v4);
545 *bytes_read += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200546 nr_commands--;
547 }
548
549 return ret;
550}
551
552static inline void bsg_set_block(struct bsg_device *bd, struct file *file)
553{
554 if (file->f_flags & O_NONBLOCK)
555 clear_bit(BSG_F_BLOCK, &bd->flags);
556 else
557 set_bit(BSG_F_BLOCK, &bd->flags);
558}
559
560static inline void bsg_set_write_perm(struct bsg_device *bd, struct file *file)
561{
562 if (file->f_mode & FMODE_WRITE)
563 set_bit(BSG_F_WRITE_PERM, &bd->flags);
564 else
565 clear_bit(BSG_F_WRITE_PERM, &bd->flags);
566}
567
Jens Axboe25fd1642007-07-17 08:52:29 +0200568/*
569 * Check if the error is a "real" error that we should return.
570 */
Jens Axboe3d6392c2007-07-09 12:38:05 +0200571static inline int err_block_err(int ret)
572{
573 if (ret && ret != -ENOSPC && ret != -ENODATA && ret != -EAGAIN)
574 return 1;
575
576 return 0;
577}
578
579static ssize_t
580bsg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
581{
582 struct bsg_device *bd = file->private_data;
583 int ret;
584 ssize_t bytes_read;
585
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100586 dprintk("%s: read %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200587
588 bsg_set_block(bd, file);
589 bytes_read = 0;
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200590 ret = __bsg_read(buf, count, bd, NULL, &bytes_read);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200591 *ppos = bytes_read;
592
593 if (!bytes_read || (bytes_read && err_block_err(ret)))
594 bytes_read = ret;
595
596 return bytes_read;
597}
598
Jens Axboe25fd1642007-07-17 08:52:29 +0200599static int __bsg_write(struct bsg_device *bd, const char __user *buf,
600 size_t count, ssize_t *bytes_written)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200601{
602 struct bsg_command *bc;
603 struct request *rq;
604 int ret, nr_commands;
605
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100606 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200607 return -EINVAL;
608
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100609 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200610 rq = NULL;
611 bc = NULL;
612 ret = 0;
613 while (nr_commands) {
614 request_queue_t *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200615
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200616 bc = bsg_alloc_command(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200617 if (IS_ERR(bc)) {
618 ret = PTR_ERR(bc);
619 bc = NULL;
620 break;
621 }
622
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100623 bc->uhdr = (struct sg_io_v4 __user *) buf;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200624 if (copy_from_user(&bc->hdr, buf, sizeof(bc->hdr))) {
625 ret = -EFAULT;
626 break;
627 }
628
629 /*
630 * get a request, fill in the blanks, and add to request queue
631 */
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100632 rq = bsg_map_hdr(bd, &bc->hdr);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200633 if (IS_ERR(rq)) {
634 ret = PTR_ERR(rq);
635 rq = NULL;
636 break;
637 }
638
639 bsg_add_command(bd, q, bc, rq);
640 bc = NULL;
641 rq = NULL;
642 nr_commands--;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100643 buf += sizeof(struct sg_io_v4);
Jens Axboe25fd1642007-07-17 08:52:29 +0200644 *bytes_written += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200645 }
646
Jens Axboe3d6392c2007-07-09 12:38:05 +0200647 if (bc)
648 bsg_free_command(bc);
649
650 return ret;
651}
652
653static ssize_t
654bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
655{
656 struct bsg_device *bd = file->private_data;
Jens Axboe25fd1642007-07-17 08:52:29 +0200657 ssize_t bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200658 int ret;
659
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100660 dprintk("%s: write %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200661
662 bsg_set_block(bd, file);
663 bsg_set_write_perm(bd, file);
664
Jens Axboe25fd1642007-07-17 08:52:29 +0200665 bytes_written = 0;
666 ret = __bsg_write(bd, buf, count, &bytes_written);
667 *ppos = bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200668
669 /*
670 * return bytes written on non-fatal errors
671 */
Jens Axboe25fd1642007-07-17 08:52:29 +0200672 if (!bytes_written || (bytes_written && err_block_err(ret)))
673 bytes_written = ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200674
Jens Axboe25fd1642007-07-17 08:52:29 +0200675 dprintk("%s: returning %Zd\n", bd->name, bytes_written);
676 return bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200677}
678
Jens Axboe3d6392c2007-07-09 12:38:05 +0200679static struct bsg_device *bsg_alloc_device(void)
680{
Jens Axboe3d6392c2007-07-09 12:38:05 +0200681 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200682
683 bd = kzalloc(sizeof(struct bsg_device), GFP_KERNEL);
684 if (unlikely(!bd))
685 return NULL;
686
687 spin_lock_init(&bd->lock);
688
Jens Axboe5309cb32007-01-23 16:24:41 +0100689 bd->max_queue = BSG_DEFAULT_CMDS;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200690
691 INIT_LIST_HEAD(&bd->busy_list);
692 INIT_LIST_HEAD(&bd->done_list);
693 INIT_HLIST_NODE(&bd->dev_list);
694
695 init_waitqueue_head(&bd->wq_free);
696 init_waitqueue_head(&bd->wq_done);
697 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200698}
699
700static int bsg_put_device(struct bsg_device *bd)
701{
702 int ret = 0;
703
704 mutex_lock(&bsg_mutex);
705
706 if (!atomic_dec_and_test(&bd->ref_count))
707 goto out;
708
709 dprintk("%s: tearing down\n", bd->name);
710
711 /*
712 * close can always block
713 */
714 set_bit(BSG_F_BLOCK, &bd->flags);
715
716 /*
717 * correct error detection baddies here again. it's the responsibility
718 * of the app to properly reap commands before close() if it wants
719 * fool-proof error detection
720 */
721 ret = bsg_complete_all_commands(bd);
722
723 blk_put_queue(bd->queue);
724 hlist_del(&bd->dev_list);
Jens Axboe5309cb32007-01-23 16:24:41 +0100725 kfree(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200726out:
727 mutex_unlock(&bsg_mutex);
728 return ret;
729}
730
731static struct bsg_device *bsg_add_device(struct inode *inode,
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200732 struct request_queue *rq,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200733 struct file *file)
734{
Jens Axboe25fd1642007-07-17 08:52:29 +0200735 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200736#ifdef BSG_DEBUG
737 unsigned char buf[32];
738#endif
739
740 bd = bsg_alloc_device();
741 if (!bd)
742 return ERR_PTR(-ENOMEM);
743
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200744 bd->queue = rq;
745 kobject_get(&rq->kobj);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200746 bsg_set_block(bd, file);
747
748 atomic_set(&bd->ref_count, 1);
749 bd->minor = iminor(inode);
750 mutex_lock(&bsg_mutex);
FUJITA Tomonori1c1133e2007-07-17 12:21:15 +0200751 hlist_add_head(&bd->dev_list, bsg_dev_idx_hash(bd->minor));
Jens Axboe3d6392c2007-07-09 12:38:05 +0200752
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200753 strncpy(bd->name, rq->bsg_dev.class_dev->class_id, sizeof(bd->name) - 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200754 dprintk("bound to <%s>, max queue %d\n",
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100755 format_dev_t(buf, inode->i_rdev), bd->max_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200756
757 mutex_unlock(&bsg_mutex);
758 return bd;
759}
760
761static struct bsg_device *__bsg_get_device(int minor)
762{
Jens Axboe3d6392c2007-07-09 12:38:05 +0200763 struct bsg_device *bd = NULL;
764 struct hlist_node *entry;
765
766 mutex_lock(&bsg_mutex);
767
FUJITA Tomonori1c1133e2007-07-17 12:21:15 +0200768 hlist_for_each(entry, bsg_dev_idx_hash(minor)) {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200769 bd = hlist_entry(entry, struct bsg_device, dev_list);
770 if (bd->minor == minor) {
771 atomic_inc(&bd->ref_count);
772 break;
773 }
774
775 bd = NULL;
776 }
777
778 mutex_unlock(&bsg_mutex);
779 return bd;
780}
781
782static struct bsg_device *bsg_get_device(struct inode *inode, struct file *file)
783{
784 struct bsg_device *bd = __bsg_get_device(iminor(inode));
785 struct bsg_class_device *bcd, *__bcd;
786
787 if (bd)
788 return bd;
789
790 /*
791 * find the class device
792 */
793 bcd = NULL;
794 mutex_lock(&bsg_mutex);
795 list_for_each_entry(__bcd, &bsg_class_list, list) {
796 if (__bcd->minor == iminor(inode)) {
797 bcd = __bcd;
798 break;
799 }
800 }
801 mutex_unlock(&bsg_mutex);
802
803 if (!bcd)
804 return ERR_PTR(-ENODEV);
805
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200806 return bsg_add_device(inode, bcd->queue, file);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200807}
808
809static int bsg_open(struct inode *inode, struct file *file)
810{
811 struct bsg_device *bd = bsg_get_device(inode, file);
812
813 if (IS_ERR(bd))
814 return PTR_ERR(bd);
815
816 file->private_data = bd;
817 return 0;
818}
819
820static int bsg_release(struct inode *inode, struct file *file)
821{
822 struct bsg_device *bd = file->private_data;
823
824 file->private_data = NULL;
825 return bsg_put_device(bd);
826}
827
828static unsigned int bsg_poll(struct file *file, poll_table *wait)
829{
830 struct bsg_device *bd = file->private_data;
831 unsigned int mask = 0;
832
833 poll_wait(file, &bd->wq_done, wait);
834 poll_wait(file, &bd->wq_free, wait);
835
836 spin_lock_irq(&bd->lock);
837 if (!list_empty(&bd->done_list))
838 mask |= POLLIN | POLLRDNORM;
839 if (bd->queued_cmds >= bd->max_queue)
840 mask |= POLLOUT;
841 spin_unlock_irq(&bd->lock);
842
843 return mask;
844}
845
Jens Axboe25fd1642007-07-17 08:52:29 +0200846static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200847{
848 struct bsg_device *bd = file->private_data;
849 int __user *uarg = (int __user *) arg;
850
Jens Axboe3d6392c2007-07-09 12:38:05 +0200851 switch (cmd) {
852 /*
853 * our own ioctls
854 */
855 case SG_GET_COMMAND_Q:
856 return put_user(bd->max_queue, uarg);
Jens Axboe5309cb32007-01-23 16:24:41 +0100857 case SG_SET_COMMAND_Q: {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200858 int queue;
859
860 if (get_user(queue, uarg))
861 return -EFAULT;
Jens Axboe5309cb32007-01-23 16:24:41 +0100862 if (queue < 1)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200863 return -EINVAL;
864
Jens Axboe5309cb32007-01-23 16:24:41 +0100865 spin_lock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200866 bd->max_queue = queue;
Jens Axboe5309cb32007-01-23 16:24:41 +0100867 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200868 return 0;
869 }
870
871 /*
872 * SCSI/sg ioctls
873 */
874 case SG_GET_VERSION_NUM:
875 case SCSI_IOCTL_GET_IDLUN:
876 case SCSI_IOCTL_GET_BUS_NUMBER:
877 case SG_SET_TIMEOUT:
878 case SG_GET_TIMEOUT:
879 case SG_GET_RESERVED_SIZE:
880 case SG_SET_RESERVED_SIZE:
881 case SG_EMULATED_HOST:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200882 case SCSI_IOCTL_SEND_COMMAND: {
883 void __user *uarg = (void __user *) arg;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200884 return scsi_cmd_ioctl(file, bd->queue, NULL, cmd, uarg);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200885 }
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100886 case SG_IO: {
887 struct request *rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200888 struct bio *bio, *bidi_bio = NULL;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100889 struct sg_io_v4 hdr;
890
891 if (copy_from_user(&hdr, uarg, sizeof(hdr)))
892 return -EFAULT;
893
894 rq = bsg_map_hdr(bd, &hdr);
895 if (IS_ERR(rq))
896 return PTR_ERR(rq);
897
898 bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200899 if (rq->next_rq)
900 bidi_bio = rq->next_rq->bio;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200901 blk_execute_rq(bd->queue, NULL, rq, 0);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200902 blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100903
904 if (copy_to_user(uarg, &hdr, sizeof(hdr)))
905 return -EFAULT;
Jens Axboeb711afa2006-12-20 11:25:23 +0100906
907 return 0;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100908 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200909 /*
910 * block device ioctls
911 */
912 default:
913#if 0
914 return ioctl_by_bdev(bd->bdev, cmd, arg);
915#else
916 return -ENOTTY;
917#endif
918 }
919}
920
921static struct file_operations bsg_fops = {
922 .read = bsg_read,
923 .write = bsg_write,
924 .poll = bsg_poll,
925 .open = bsg_open,
926 .release = bsg_release,
Jens Axboe25fd1642007-07-17 08:52:29 +0200927 .unlocked_ioctl = bsg_ioctl,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200928 .owner = THIS_MODULE,
929};
930
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200931void bsg_unregister_queue(struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200932{
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200933 struct bsg_class_device *bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200934
Jens Axboe25fd1642007-07-17 08:52:29 +0200935 WARN_ON(!bcd->class_dev);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200936
937 mutex_lock(&bsg_mutex);
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200938 sysfs_remove_link(&q->kobj, "bsg");
Jens Axboe46f6ef42007-07-17 08:56:10 +0200939 class_device_destroy(bsg_class, MKDEV(bsg_major, bcd->minor));
Jens Axboe3d6392c2007-07-09 12:38:05 +0200940 bcd->class_dev = NULL;
941 list_del_init(&bcd->list);
FUJITA Tomonori292b7f22007-03-28 13:29:58 +0200942 bsg_device_nr--;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200943 mutex_unlock(&bsg_mutex);
944}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +0200945EXPORT_SYMBOL_GPL(bsg_unregister_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200946
FUJITA Tomonori4cf07232007-03-30 11:19:39 +0200947int bsg_register_queue(struct request_queue *q, const char *name)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200948{
FUJITA Tomonori292b7f22007-03-28 13:29:58 +0200949 struct bsg_class_device *bcd, *__bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200950 dev_t dev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +0200951 int ret = -EMFILE;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +0200952 struct class_device *class_dev = NULL;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200953
954 /*
955 * we need a proper transport to send commands, not a stacked device
956 */
957 if (!q->request_fn)
958 return 0;
959
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200960 bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200961 memset(bcd, 0, sizeof(*bcd));
962 INIT_LIST_HEAD(&bcd->list);
963
964 mutex_lock(&bsg_mutex);
FUJITA Tomonori292b7f22007-03-28 13:29:58 +0200965 if (bsg_device_nr == BSG_MAX_DEVS) {
966 printk(KERN_ERR "bsg: too many bsg devices\n");
967 goto err;
968 }
969
970retry:
971 list_for_each_entry(__bcd, &bsg_class_list, list) {
972 if (__bcd->minor == bsg_minor_idx) {
973 bsg_minor_idx++;
974 if (bsg_minor_idx == BSG_MAX_DEVS)
975 bsg_minor_idx = 0;
976 goto retry;
977 }
978 }
979
980 bcd->minor = bsg_minor_idx++;
981 if (bsg_minor_idx == BSG_MAX_DEVS)
982 bsg_minor_idx = 0;
983
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200984 bcd->queue = q;
Jens Axboe46f6ef42007-07-17 08:56:10 +0200985 dev = MKDEV(bsg_major, bcd->minor);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +0200986 class_dev = class_device_create(bsg_class, NULL, dev, bcd->dev, "%s", name);
987 if (IS_ERR(class_dev)) {
988 ret = PTR_ERR(class_dev);
Jens Axboe264a0472007-01-23 16:30:17 +0100989 goto err;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +0200990 }
991 bcd->class_dev = class_dev;
992
Linus Torvaldsabce8912007-07-16 11:18:23 -0700993 if (q->kobj.sd) {
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +0200994 ret = sysfs_create_link(&q->kobj, &bcd->class_dev->kobj, "bsg");
995 if (ret)
996 goto err;
997 }
998
Jens Axboe3d6392c2007-07-09 12:38:05 +0200999 list_add_tail(&bcd->list, &bsg_class_list);
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001000 bsg_device_nr++;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001001
Jens Axboe3d6392c2007-07-09 12:38:05 +02001002 mutex_unlock(&bsg_mutex);
1003 return 0;
Jens Axboe264a0472007-01-23 16:30:17 +01001004err:
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001005 if (class_dev)
Jens Axboe46f6ef42007-07-17 08:56:10 +02001006 class_device_destroy(bsg_class, MKDEV(bsg_major, bcd->minor));
Jens Axboe264a0472007-01-23 16:30:17 +01001007 mutex_unlock(&bsg_mutex);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001008 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001009}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +02001010EXPORT_SYMBOL_GPL(bsg_register_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001011
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001012static int bsg_add(struct class_device *cl_dev, struct class_interface *cl_intf)
1013{
1014 int ret;
1015 struct scsi_device *sdp = to_scsi_device(cl_dev->dev);
1016 struct request_queue *rq = sdp->request_queue;
1017
1018 if (rq->kobj.parent)
1019 ret = bsg_register_queue(rq, kobject_name(rq->kobj.parent));
1020 else
1021 ret = bsg_register_queue(rq, kobject_name(&sdp->sdev_gendev.kobj));
1022 return ret;
1023}
1024
1025static void bsg_remove(struct class_device *cl_dev, struct class_interface *cl_intf)
1026{
1027 bsg_unregister_queue(to_scsi_device(cl_dev->dev)->request_queue);
1028}
1029
1030static struct class_interface bsg_intf = {
1031 .add = bsg_add,
1032 .remove = bsg_remove,
1033};
1034
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001035static struct cdev bsg_cdev = {
1036 .kobj = {.name = "bsg", },
1037 .owner = THIS_MODULE,
1038};
1039
Jens Axboe3d6392c2007-07-09 12:38:05 +02001040static int __init bsg_init(void)
1041{
1042 int ret, i;
Jens Axboe46f6ef42007-07-17 08:56:10 +02001043 dev_t devid;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001044
Jens Axboe5309cb32007-01-23 16:24:41 +01001045 bsg_cmd_cachep = kmem_cache_create("bsg_cmd",
1046 sizeof(struct bsg_command), 0, 0, NULL, NULL);
1047 if (!bsg_cmd_cachep) {
1048 printk(KERN_ERR "bsg: failed creating slab cache\n");
1049 return -ENOMEM;
1050 }
1051
Jens Axboe25fd1642007-07-17 08:52:29 +02001052 for (i = 0; i < BSG_LIST_ARRAY_SIZE; i++)
Jens Axboe3d6392c2007-07-09 12:38:05 +02001053 INIT_HLIST_HEAD(&bsg_device_list[i]);
1054
1055 bsg_class = class_create(THIS_MODULE, "bsg");
Jens Axboe5309cb32007-01-23 16:24:41 +01001056 if (IS_ERR(bsg_class)) {
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001057 ret = PTR_ERR(bsg_class);
1058 goto destroy_kmemcache;
Jens Axboe5309cb32007-01-23 16:24:41 +01001059 }
Jens Axboe3d6392c2007-07-09 12:38:05 +02001060
Jens Axboe46f6ef42007-07-17 08:56:10 +02001061 ret = alloc_chrdev_region(&devid, 0, BSG_MAX_DEVS, "bsg");
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001062 if (ret)
1063 goto destroy_bsg_class;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001064
Jens Axboe46f6ef42007-07-17 08:56:10 +02001065 bsg_major = MAJOR(devid);
1066
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001067 cdev_init(&bsg_cdev, &bsg_fops);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001068 ret = cdev_add(&bsg_cdev, MKDEV(bsg_major, 0), BSG_MAX_DEVS);
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001069 if (ret)
1070 goto unregister_chrdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001071
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001072 ret = scsi_register_interface(&bsg_intf);
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001073 if (ret)
1074 goto remove_cdev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001075
Jens Axboe5d3a8cd2007-07-17 15:10:09 +02001076 printk(KERN_INFO BSG_DESCRIPTION " version " BSG_VERSION
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001077 " loaded (major %d)\n", bsg_major);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001078 return 0;
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001079remove_cdev:
1080 printk(KERN_ERR "bsg: failed register scsi interface %d\n", ret);
1081 cdev_del(&bsg_cdev);
1082unregister_chrdev:
1083 unregister_chrdev_region(MKDEV(bsg_major, 0), BSG_MAX_DEVS);
1084destroy_bsg_class:
1085 class_destroy(bsg_class);
1086destroy_kmemcache:
1087 kmem_cache_destroy(bsg_cmd_cachep);
1088 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001089}
1090
1091MODULE_AUTHOR("Jens Axboe");
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001092MODULE_DESCRIPTION(BSG_DESCRIPTION);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001093MODULE_LICENSE("GPL");
1094
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001095device_initcall(bsg_init);