blob: 576933fe1860ff1c07d4603ecad5a0726447f830 [file] [log] [blame]
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
36static char bsg_version[] = "block layer sg (bsg) 0.4";
37
Jens Axboe3d6392c2007-07-09 12:38:05 +020038struct bsg_device {
Jens Axboe3d6392c2007-07-09 12:38:05 +020039 request_queue_t *queue;
40 spinlock_t lock;
41 struct list_head busy_list;
42 struct list_head done_list;
43 struct hlist_node dev_list;
44 atomic_t ref_count;
45 int minor;
46 int queued_cmds;
47 int done_cmds;
Jens Axboe3d6392c2007-07-09 12:38:05 +020048 wait_queue_head_t wq_done;
49 wait_queue_head_t wq_free;
FUJITA Tomonorid351af02007-07-09 12:40:35 +020050 char name[BUS_ID_SIZE];
Jens Axboe3d6392c2007-07-09 12:38:05 +020051 int max_queue;
52 unsigned long flags;
53};
54
55enum {
56 BSG_F_BLOCK = 1,
57 BSG_F_WRITE_PERM = 2,
58};
59
Jens Axboe5309cb32007-01-23 16:24:41 +010060#define BSG_DEFAULT_CMDS 64
FUJITA Tomonori292b7f22007-03-28 13:29:58 +020061#define BSG_MAX_DEVS 32768
Jens Axboe3d6392c2007-07-09 12:38:05 +020062
63#undef BSG_DEBUG
64
65#ifdef BSG_DEBUG
66#define dprintk(fmt, args...) printk(KERN_ERR "%s: " fmt, __FUNCTION__, ##args)
67#else
68#define dprintk(fmt, args...)
69#endif
70
71#define list_entry_bc(entry) list_entry((entry), struct bsg_command, list)
72
73/*
74 * just for testing
75 */
76#define BSG_MAJOR (240)
77
78static DEFINE_MUTEX(bsg_mutex);
FUJITA Tomonori292b7f22007-03-28 13:29:58 +020079static int bsg_device_nr, bsg_minor_idx;
Jens Axboe3d6392c2007-07-09 12:38:05 +020080
81#define BSG_LIST_SIZE (8)
82#define bsg_list_idx(minor) ((minor) & (BSG_LIST_SIZE - 1))
83static struct hlist_head bsg_device_list[BSG_LIST_SIZE];
84
85static struct class *bsg_class;
86static LIST_HEAD(bsg_class_list);
87
Jens Axboe5309cb32007-01-23 16:24:41 +010088static struct kmem_cache *bsg_cmd_cachep;
89
Jens Axboe3d6392c2007-07-09 12:38:05 +020090/*
91 * our internal command type
92 */
93struct bsg_command {
94 struct bsg_device *bd;
95 struct list_head list;
96 struct request *rq;
97 struct bio *bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +020098 struct bio *bidi_bio;
Jens Axboe3d6392c2007-07-09 12:38:05 +020099 int err;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100100 struct sg_io_v4 hdr;
101 struct sg_io_v4 __user *uhdr;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200102 char sense[SCSI_SENSE_BUFFERSIZE];
103};
104
105static void bsg_free_command(struct bsg_command *bc)
106{
107 struct bsg_device *bd = bc->bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200108 unsigned long flags;
109
Jens Axboe5309cb32007-01-23 16:24:41 +0100110 kmem_cache_free(bsg_cmd_cachep, bc);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200111
112 spin_lock_irqsave(&bd->lock, flags);
113 bd->queued_cmds--;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200114 spin_unlock_irqrestore(&bd->lock, flags);
115
116 wake_up(&bd->wq_free);
117}
118
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200119static struct bsg_command *bsg_alloc_command(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200120{
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200121 struct bsg_command *bc = ERR_PTR(-EINVAL);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200122
123 spin_lock_irq(&bd->lock);
124
125 if (bd->queued_cmds >= bd->max_queue)
126 goto out;
127
Jens Axboe3d6392c2007-07-09 12:38:05 +0200128 bd->queued_cmds++;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200129 spin_unlock_irq(&bd->lock);
130
Jens Axboe5309cb32007-01-23 16:24:41 +0100131 bc = kmem_cache_alloc(bsg_cmd_cachep, GFP_USER);
132 if (unlikely(!bc)) {
133 spin_lock_irq(&bd->lock);
FUJITA Tomonori7e75d732007-01-24 09:05:54 +0100134 bd->queued_cmds--;
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200135 bc = ERR_PTR(-ENOMEM);
FUJITA Tomonori7e75d732007-01-24 09:05:54 +0100136 goto out;
Jens Axboe5309cb32007-01-23 16:24:41 +0100137 }
138
Jens Axboe3d6392c2007-07-09 12:38:05 +0200139 memset(bc, 0, sizeof(*bc));
140 bc->bd = bd;
141 INIT_LIST_HEAD(&bc->list);
Jens Axboe5309cb32007-01-23 16:24:41 +0100142 dprintk("%s: returning free cmd %p\n", bd->name, bc);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200143 return bc;
144out:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200145 spin_unlock_irq(&bd->lock);
146 return bc;
147}
148
149static inline void
150bsg_del_done_cmd(struct bsg_device *bd, struct bsg_command *bc)
151{
152 bd->done_cmds--;
153 list_del(&bc->list);
154}
155
156static inline void
157bsg_add_done_cmd(struct bsg_device *bd, struct bsg_command *bc)
158{
159 bd->done_cmds++;
160 list_add_tail(&bc->list, &bd->done_list);
161 wake_up(&bd->wq_done);
162}
163
164static inline int bsg_io_schedule(struct bsg_device *bd, int state)
165{
166 DEFINE_WAIT(wait);
167 int ret = 0;
168
169 spin_lock_irq(&bd->lock);
170
171 BUG_ON(bd->done_cmds > bd->queued_cmds);
172
173 /*
174 * -ENOSPC or -ENODATA? I'm going for -ENODATA, meaning "I have no
175 * work to do", even though we return -ENOSPC after this same test
176 * during bsg_write() -- there, it means our buffer can't have more
177 * bsg_commands added to it, thus has no space left.
178 */
179 if (bd->done_cmds == bd->queued_cmds) {
180 ret = -ENODATA;
181 goto unlock;
182 }
183
184 if (!test_bit(BSG_F_BLOCK, &bd->flags)) {
185 ret = -EAGAIN;
186 goto unlock;
187 }
188
189 prepare_to_wait(&bd->wq_done, &wait, state);
190 spin_unlock_irq(&bd->lock);
191 io_schedule();
192 finish_wait(&bd->wq_done, &wait);
193
194 if ((state == TASK_INTERRUPTIBLE) && signal_pending(current))
195 ret = -ERESTARTSYS;
196
197 return ret;
198unlock:
199 spin_unlock_irq(&bd->lock);
200 return ret;
201}
202
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100203static int blk_fill_sgv4_hdr_rq(request_queue_t *q, struct request *rq,
204 struct sg_io_v4 *hdr, int has_write_perm)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200205{
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100206 memset(rq->cmd, 0, BLK_MAX_CDB); /* ATAPI hates garbage after CDB */
207
208 if (copy_from_user(rq->cmd, (void *)(unsigned long)hdr->request,
209 hdr->request_len))
210 return -EFAULT;
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200211
212 if (hdr->subprotocol == BSG_SUB_PROTOCOL_SCSI_CMD) {
213 if (blk_verify_command(rq->cmd, has_write_perm))
214 return -EPERM;
215 } else if (!capable(CAP_SYS_RAWIO))
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100216 return -EPERM;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200217
218 /*
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100219 * fill in request structure
Jens Axboe3d6392c2007-07-09 12:38:05 +0200220 */
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100221 rq->cmd_len = hdr->request_len;
222 rq->cmd_type = REQ_TYPE_BLOCK_PC;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200223
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100224 rq->timeout = (hdr->timeout * HZ) / 1000;
225 if (!rq->timeout)
226 rq->timeout = q->sg_timeout;
227 if (!rq->timeout)
228 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200229
230 return 0;
231}
232
233/*
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100234 * Check if sg_io_v4 from user is allowed and valid
235 */
236static int
237bsg_validate_sgv4_hdr(request_queue_t *q, struct sg_io_v4 *hdr, int *rw)
238{
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200239 int ret = 0;
240
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100241 if (hdr->guard != 'Q')
242 return -EINVAL;
243 if (hdr->request_len > BLK_MAX_CDB)
244 return -EINVAL;
245 if (hdr->dout_xfer_len > (q->max_sectors << 9) ||
246 hdr->din_xfer_len > (q->max_sectors << 9))
247 return -EIO;
248
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200249 switch (hdr->protocol) {
250 case BSG_PROTOCOL_SCSI:
251 switch (hdr->subprotocol) {
252 case BSG_SUB_PROTOCOL_SCSI_CMD:
253 case BSG_SUB_PROTOCOL_SCSI_TRANSPORT:
254 break;
255 default:
256 ret = -EINVAL;
257 }
258 break;
259 default:
260 ret = -EINVAL;
261 }
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100262
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100263 *rw = hdr->dout_xfer_len ? WRITE : READ;
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200264 return ret;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100265}
266
267/*
268 * map sg_io_v4 to a request.
Jens Axboe3d6392c2007-07-09 12:38:05 +0200269 */
270static struct request *
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100271bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200272{
273 request_queue_t *q = bd->queue;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200274 struct request *rq, *next_rq = NULL;
Jens Axboe2ef70862006-12-20 11:26:11 +0100275 int ret, rw = 0; /* shut up gcc */
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100276 unsigned int dxfer_len;
277 void *dxferp = NULL;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200278
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100279 dprintk("map hdr %llx/%u %llx/%u\n", (unsigned long long) hdr->dout_xferp,
280 hdr->dout_xfer_len, (unsigned long long) hdr->din_xferp,
281 hdr->din_xfer_len);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200282
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100283 ret = bsg_validate_sgv4_hdr(q, hdr, &rw);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200284 if (ret)
285 return ERR_PTR(ret);
286
287 /*
288 * map scatter-gather elements seperately and string them to request
289 */
290 rq = blk_get_request(q, rw, GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200291 if (!rq)
292 return ERR_PTR(-ENOMEM);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100293 ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, test_bit(BSG_F_WRITE_PERM,
294 &bd->flags));
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200295 if (ret)
296 goto out;
297
298 if (rw == WRITE && hdr->din_xfer_len) {
299 if (!test_bit(QUEUE_FLAG_BIDI, &q->queue_flags)) {
300 ret = -EOPNOTSUPP;
301 goto out;
302 }
303
304 next_rq = blk_get_request(q, READ, GFP_KERNEL);
305 if (!next_rq) {
306 ret = -ENOMEM;
307 goto out;
308 }
309 rq->next_rq = next_rq;
310
311 dxferp = (void*)(unsigned long)hdr->din_xferp;
312 ret = blk_rq_map_user(q, next_rq, dxferp, hdr->din_xfer_len);
313 if (ret)
314 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200315 }
316
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100317 if (hdr->dout_xfer_len) {
318 dxfer_len = hdr->dout_xfer_len;
319 dxferp = (void*)(unsigned long)hdr->dout_xferp;
320 } else if (hdr->din_xfer_len) {
321 dxfer_len = hdr->din_xfer_len;
322 dxferp = (void*)(unsigned long)hdr->din_xferp;
323 } else
324 dxfer_len = 0;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200325
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100326 if (dxfer_len) {
327 ret = blk_rq_map_user(q, rq, dxferp, dxfer_len);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200328 if (ret)
329 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200330 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200331 return rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200332out:
333 blk_put_request(rq);
334 if (next_rq) {
335 blk_rq_unmap_user(next_rq->bio);
336 blk_put_request(next_rq);
337 }
338 return ERR_PTR(ret);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200339}
340
341/*
342 * async completion call-back from the block layer, when scsi/ide/whatever
343 * calls end_that_request_last() on a request
344 */
345static void bsg_rq_end_io(struct request *rq, int uptodate)
346{
347 struct bsg_command *bc = rq->end_io_data;
348 struct bsg_device *bd = bc->bd;
349 unsigned long flags;
350
Jens Axboe5309cb32007-01-23 16:24:41 +0100351 dprintk("%s: finished rq %p bc %p, bio %p stat %d\n",
352 bd->name, rq, bc, bc->bio, uptodate);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200353
354 bc->hdr.duration = jiffies_to_msecs(jiffies - bc->hdr.duration);
355
356 spin_lock_irqsave(&bd->lock, flags);
357 list_del(&bc->list);
358 bsg_add_done_cmd(bd, bc);
359 spin_unlock_irqrestore(&bd->lock, flags);
360}
361
362/*
363 * do final setup of a 'bc' and submit the matching 'rq' to the block
364 * layer for io
365 */
366static void bsg_add_command(struct bsg_device *bd, request_queue_t *q,
367 struct bsg_command *bc, struct request *rq)
368{
369 rq->sense = bc->sense;
370 rq->sense_len = 0;
371
372 /*
373 * add bc command to busy queue and submit rq for io
374 */
375 bc->rq = rq;
376 bc->bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200377 if (rq->next_rq)
378 bc->bidi_bio = rq->next_rq->bio;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200379 bc->hdr.duration = jiffies;
380 spin_lock_irq(&bd->lock);
381 list_add_tail(&bc->list, &bd->busy_list);
382 spin_unlock_irq(&bd->lock);
383
384 dprintk("%s: queueing rq %p, bc %p\n", bd->name, rq, bc);
385
386 rq->end_io_data = bc;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200387 blk_execute_rq_nowait(q, NULL, rq, 1, bsg_rq_end_io);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200388}
389
390static inline struct bsg_command *bsg_next_done_cmd(struct bsg_device *bd)
391{
392 struct bsg_command *bc = NULL;
393
394 spin_lock_irq(&bd->lock);
395 if (bd->done_cmds) {
396 bc = list_entry_bc(bd->done_list.next);
397 bsg_del_done_cmd(bd, bc);
398 }
399 spin_unlock_irq(&bd->lock);
400
401 return bc;
402}
403
404/*
405 * Get a finished command from the done list
406 */
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200407static struct bsg_command *bsg_get_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200408{
409 struct bsg_command *bc;
410 int ret;
411
412 do {
413 bc = bsg_next_done_cmd(bd);
414 if (bc)
415 break;
416
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200417 if (!test_bit(BSG_F_BLOCK, &bd->flags)) {
418 bc = ERR_PTR(-EAGAIN);
419 break;
420 }
421
422 ret = wait_event_interruptible(bd->wq_done, bd->done_cmds);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200423 if (ret) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200424 bc = ERR_PTR(-ERESTARTSYS);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200425 break;
426 }
427 } while (1);
428
429 dprintk("%s: returning done %p\n", bd->name, bc);
430
431 return bc;
432}
433
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100434static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr,
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200435 struct bio *bio, struct bio *bidi_bio)
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100436{
437 int ret = 0;
438
439 dprintk("rq %p bio %p %u\n", rq, bio, rq->errors);
440 /*
441 * fill in all the output members
442 */
443 hdr->device_status = status_byte(rq->errors);
444 hdr->transport_status = host_byte(rq->errors);
445 hdr->driver_status = driver_byte(rq->errors);
446 hdr->info = 0;
447 if (hdr->device_status || hdr->transport_status || hdr->driver_status)
448 hdr->info |= SG_INFO_CHECK;
449 hdr->din_resid = rq->data_len;
450 hdr->response_len = 0;
451
452 if (rq->sense_len && hdr->response) {
453 int len = min((unsigned int) hdr->max_response_len,
454 rq->sense_len);
455
456 ret = copy_to_user((void*)(unsigned long)hdr->response,
457 rq->sense, len);
458 if (!ret)
459 hdr->response_len = len;
460 else
461 ret = -EFAULT;
462 }
463
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200464 if (rq->next_rq) {
465 blk_rq_unmap_user(bidi_bio);
466 blk_put_request(rq->next_rq);
467 }
468
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100469 blk_rq_unmap_user(bio);
470 blk_put_request(rq);
471
472 return ret;
473}
474
Jens Axboe3d6392c2007-07-09 12:38:05 +0200475static int bsg_complete_all_commands(struct bsg_device *bd)
476{
477 struct bsg_command *bc;
478 int ret, tret;
479
480 dprintk("%s: entered\n", bd->name);
481
482 set_bit(BSG_F_BLOCK, &bd->flags);
483
484 /*
485 * wait for all commands to complete
486 */
487 ret = 0;
488 do {
489 ret = bsg_io_schedule(bd, TASK_UNINTERRUPTIBLE);
490 /*
491 * look for -ENODATA specifically -- we'll sometimes get
492 * -ERESTARTSYS when we've taken a signal, but we can't
493 * return until we're done freeing the queue, so ignore
494 * it. The signal will get handled when we're done freeing
495 * the bsg_device.
496 */
497 } while (ret != -ENODATA);
498
499 /*
500 * discard done commands
501 */
502 ret = 0;
503 do {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200504 spin_lock_irq(&bd->lock);
505 if (!bd->queued_cmds) {
506 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200507 break;
508 }
FUJITA Tomonoriefba1a32007-06-07 13:24:06 +0200509 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200510
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200511 bc = bsg_get_done_cmd(bd);
512 if (IS_ERR(bc))
513 break;
514
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200515 tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
516 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200517 if (!ret)
518 ret = tret;
519
520 bsg_free_command(bc);
521 } while (1);
522
523 return ret;
524}
525
Jens Axboe3d6392c2007-07-09 12:38:05 +0200526static ssize_t
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200527__bsg_read(char __user *buf, size_t count, struct bsg_device *bd,
528 const struct iovec *iov, ssize_t *bytes_read)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200529{
530 struct bsg_command *bc;
531 int nr_commands, ret;
532
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100533 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200534 return -EINVAL;
535
536 ret = 0;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100537 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200538 while (nr_commands) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200539 bc = bsg_get_done_cmd(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200540 if (IS_ERR(bc)) {
541 ret = PTR_ERR(bc);
542 break;
543 }
544
545 /*
546 * this is the only case where we need to copy data back
547 * after completing the request. so do that here,
548 * bsg_complete_work() cannot do that for us
549 */
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200550 ret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
551 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200552
553 if (copy_to_user(buf, (char *) &bc->hdr, sizeof(bc->hdr)))
554 ret = -EFAULT;
555
556 bsg_free_command(bc);
557
558 if (ret)
559 break;
560
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100561 buf += sizeof(struct sg_io_v4);
562 *bytes_read += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200563 nr_commands--;
564 }
565
566 return ret;
567}
568
569static inline void bsg_set_block(struct bsg_device *bd, struct file *file)
570{
571 if (file->f_flags & O_NONBLOCK)
572 clear_bit(BSG_F_BLOCK, &bd->flags);
573 else
574 set_bit(BSG_F_BLOCK, &bd->flags);
575}
576
577static inline void bsg_set_write_perm(struct bsg_device *bd, struct file *file)
578{
579 if (file->f_mode & FMODE_WRITE)
580 set_bit(BSG_F_WRITE_PERM, &bd->flags);
581 else
582 clear_bit(BSG_F_WRITE_PERM, &bd->flags);
583}
584
585static inline int err_block_err(int ret)
586{
587 if (ret && ret != -ENOSPC && ret != -ENODATA && ret != -EAGAIN)
588 return 1;
589
590 return 0;
591}
592
593static ssize_t
594bsg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
595{
596 struct bsg_device *bd = file->private_data;
597 int ret;
598 ssize_t bytes_read;
599
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100600 dprintk("%s: read %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200601
602 bsg_set_block(bd, file);
603 bytes_read = 0;
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200604 ret = __bsg_read(buf, count, bd, NULL, &bytes_read);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200605 *ppos = bytes_read;
606
607 if (!bytes_read || (bytes_read && err_block_err(ret)))
608 bytes_read = ret;
609
610 return bytes_read;
611}
612
613static ssize_t __bsg_write(struct bsg_device *bd, const char __user *buf,
614 size_t count, ssize_t *bytes_read)
615{
616 struct bsg_command *bc;
617 struct request *rq;
618 int ret, nr_commands;
619
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100620 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200621 return -EINVAL;
622
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100623 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200624 rq = NULL;
625 bc = NULL;
626 ret = 0;
627 while (nr_commands) {
628 request_queue_t *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200629
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200630 bc = bsg_alloc_command(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200631 if (IS_ERR(bc)) {
632 ret = PTR_ERR(bc);
633 bc = NULL;
634 break;
635 }
636
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100637 bc->uhdr = (struct sg_io_v4 __user *) buf;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200638 if (copy_from_user(&bc->hdr, buf, sizeof(bc->hdr))) {
639 ret = -EFAULT;
640 break;
641 }
642
643 /*
644 * get a request, fill in the blanks, and add to request queue
645 */
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100646 rq = bsg_map_hdr(bd, &bc->hdr);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200647 if (IS_ERR(rq)) {
648 ret = PTR_ERR(rq);
649 rq = NULL;
650 break;
651 }
652
653 bsg_add_command(bd, q, bc, rq);
654 bc = NULL;
655 rq = NULL;
656 nr_commands--;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100657 buf += sizeof(struct sg_io_v4);
658 *bytes_read += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200659 }
660
Jens Axboe3d6392c2007-07-09 12:38:05 +0200661 if (bc)
662 bsg_free_command(bc);
663
664 return ret;
665}
666
667static ssize_t
668bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
669{
670 struct bsg_device *bd = file->private_data;
671 ssize_t bytes_read;
672 int ret;
673
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100674 dprintk("%s: write %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200675
676 bsg_set_block(bd, file);
677 bsg_set_write_perm(bd, file);
678
679 bytes_read = 0;
680 ret = __bsg_write(bd, buf, count, &bytes_read);
681 *ppos = bytes_read;
682
683 /*
684 * return bytes written on non-fatal errors
685 */
686 if (!bytes_read || (bytes_read && err_block_err(ret)))
687 bytes_read = ret;
688
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100689 dprintk("%s: returning %Zd\n", bd->name, bytes_read);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200690 return bytes_read;
691}
692
Jens Axboe3d6392c2007-07-09 12:38:05 +0200693static struct bsg_device *bsg_alloc_device(void)
694{
Jens Axboe3d6392c2007-07-09 12:38:05 +0200695 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200696
697 bd = kzalloc(sizeof(struct bsg_device), GFP_KERNEL);
698 if (unlikely(!bd))
699 return NULL;
700
701 spin_lock_init(&bd->lock);
702
Jens Axboe5309cb32007-01-23 16:24:41 +0100703 bd->max_queue = BSG_DEFAULT_CMDS;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200704
705 INIT_LIST_HEAD(&bd->busy_list);
706 INIT_LIST_HEAD(&bd->done_list);
707 INIT_HLIST_NODE(&bd->dev_list);
708
709 init_waitqueue_head(&bd->wq_free);
710 init_waitqueue_head(&bd->wq_done);
711 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200712}
713
714static int bsg_put_device(struct bsg_device *bd)
715{
716 int ret = 0;
717
718 mutex_lock(&bsg_mutex);
719
720 if (!atomic_dec_and_test(&bd->ref_count))
721 goto out;
722
723 dprintk("%s: tearing down\n", bd->name);
724
725 /*
726 * close can always block
727 */
728 set_bit(BSG_F_BLOCK, &bd->flags);
729
730 /*
731 * correct error detection baddies here again. it's the responsibility
732 * of the app to properly reap commands before close() if it wants
733 * fool-proof error detection
734 */
735 ret = bsg_complete_all_commands(bd);
736
737 blk_put_queue(bd->queue);
738 hlist_del(&bd->dev_list);
Jens Axboe5309cb32007-01-23 16:24:41 +0100739 kfree(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200740out:
741 mutex_unlock(&bsg_mutex);
742 return ret;
743}
744
745static struct bsg_device *bsg_add_device(struct inode *inode,
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200746 struct request_queue *rq,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200747 struct file *file)
748{
749 struct bsg_device *bd = NULL;
750#ifdef BSG_DEBUG
751 unsigned char buf[32];
752#endif
753
754 bd = bsg_alloc_device();
755 if (!bd)
756 return ERR_PTR(-ENOMEM);
757
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200758 bd->queue = rq;
759 kobject_get(&rq->kobj);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200760 bsg_set_block(bd, file);
761
762 atomic_set(&bd->ref_count, 1);
763 bd->minor = iminor(inode);
764 mutex_lock(&bsg_mutex);
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200765 hlist_add_head(&bd->dev_list, &bsg_device_list[bsg_list_idx(bd->minor)]);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200766
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200767 strncpy(bd->name, rq->bsg_dev.class_dev->class_id, sizeof(bd->name) - 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200768 dprintk("bound to <%s>, max queue %d\n",
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100769 format_dev_t(buf, inode->i_rdev), bd->max_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200770
771 mutex_unlock(&bsg_mutex);
772 return bd;
773}
774
775static struct bsg_device *__bsg_get_device(int minor)
776{
777 struct hlist_head *list = &bsg_device_list[bsg_list_idx(minor)];
778 struct bsg_device *bd = NULL;
779 struct hlist_node *entry;
780
781 mutex_lock(&bsg_mutex);
782
783 hlist_for_each(entry, list) {
784 bd = hlist_entry(entry, struct bsg_device, dev_list);
785 if (bd->minor == minor) {
786 atomic_inc(&bd->ref_count);
787 break;
788 }
789
790 bd = NULL;
791 }
792
793 mutex_unlock(&bsg_mutex);
794 return bd;
795}
796
797static struct bsg_device *bsg_get_device(struct inode *inode, struct file *file)
798{
799 struct bsg_device *bd = __bsg_get_device(iminor(inode));
800 struct bsg_class_device *bcd, *__bcd;
801
802 if (bd)
803 return bd;
804
805 /*
806 * find the class device
807 */
808 bcd = NULL;
809 mutex_lock(&bsg_mutex);
810 list_for_each_entry(__bcd, &bsg_class_list, list) {
811 if (__bcd->minor == iminor(inode)) {
812 bcd = __bcd;
813 break;
814 }
815 }
816 mutex_unlock(&bsg_mutex);
817
818 if (!bcd)
819 return ERR_PTR(-ENODEV);
820
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200821 return bsg_add_device(inode, bcd->queue, file);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200822}
823
824static int bsg_open(struct inode *inode, struct file *file)
825{
826 struct bsg_device *bd = bsg_get_device(inode, file);
827
828 if (IS_ERR(bd))
829 return PTR_ERR(bd);
830
831 file->private_data = bd;
832 return 0;
833}
834
835static int bsg_release(struct inode *inode, struct file *file)
836{
837 struct bsg_device *bd = file->private_data;
838
839 file->private_data = NULL;
840 return bsg_put_device(bd);
841}
842
843static unsigned int bsg_poll(struct file *file, poll_table *wait)
844{
845 struct bsg_device *bd = file->private_data;
846 unsigned int mask = 0;
847
848 poll_wait(file, &bd->wq_done, wait);
849 poll_wait(file, &bd->wq_free, wait);
850
851 spin_lock_irq(&bd->lock);
852 if (!list_empty(&bd->done_list))
853 mask |= POLLIN | POLLRDNORM;
854 if (bd->queued_cmds >= bd->max_queue)
855 mask |= POLLOUT;
856 spin_unlock_irq(&bd->lock);
857
858 return mask;
859}
860
861static int
862bsg_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
863 unsigned long arg)
864{
865 struct bsg_device *bd = file->private_data;
866 int __user *uarg = (int __user *) arg;
867
868 if (!bd)
869 return -ENXIO;
870
871 switch (cmd) {
872 /*
873 * our own ioctls
874 */
875 case SG_GET_COMMAND_Q:
876 return put_user(bd->max_queue, uarg);
Jens Axboe5309cb32007-01-23 16:24:41 +0100877 case SG_SET_COMMAND_Q: {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200878 int queue;
879
880 if (get_user(queue, uarg))
881 return -EFAULT;
Jens Axboe5309cb32007-01-23 16:24:41 +0100882 if (queue < 1)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200883 return -EINVAL;
884
Jens Axboe5309cb32007-01-23 16:24:41 +0100885 spin_lock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200886 bd->max_queue = queue;
Jens Axboe5309cb32007-01-23 16:24:41 +0100887 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200888 return 0;
889 }
890
891 /*
892 * SCSI/sg ioctls
893 */
894 case SG_GET_VERSION_NUM:
895 case SCSI_IOCTL_GET_IDLUN:
896 case SCSI_IOCTL_GET_BUS_NUMBER:
897 case SG_SET_TIMEOUT:
898 case SG_GET_TIMEOUT:
899 case SG_GET_RESERVED_SIZE:
900 case SG_SET_RESERVED_SIZE:
901 case SG_EMULATED_HOST:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200902 case SCSI_IOCTL_SEND_COMMAND: {
903 void __user *uarg = (void __user *) arg;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200904 return scsi_cmd_ioctl(file, bd->queue, NULL, cmd, uarg);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200905 }
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100906 case SG_IO: {
907 struct request *rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200908 struct bio *bio, *bidi_bio = NULL;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100909 struct sg_io_v4 hdr;
910
911 if (copy_from_user(&hdr, uarg, sizeof(hdr)))
912 return -EFAULT;
913
914 rq = bsg_map_hdr(bd, &hdr);
915 if (IS_ERR(rq))
916 return PTR_ERR(rq);
917
918 bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200919 if (rq->next_rq)
920 bidi_bio = rq->next_rq->bio;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200921 blk_execute_rq(bd->queue, NULL, rq, 0);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200922 blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100923
924 if (copy_to_user(uarg, &hdr, sizeof(hdr)))
925 return -EFAULT;
Jens Axboeb711afa2006-12-20 11:25:23 +0100926
927 return 0;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100928 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200929 /*
930 * block device ioctls
931 */
932 default:
933#if 0
934 return ioctl_by_bdev(bd->bdev, cmd, arg);
935#else
936 return -ENOTTY;
937#endif
938 }
939}
940
941static struct file_operations bsg_fops = {
942 .read = bsg_read,
943 .write = bsg_write,
944 .poll = bsg_poll,
945 .open = bsg_open,
946 .release = bsg_release,
947 .ioctl = bsg_ioctl,
948 .owner = THIS_MODULE,
949};
950
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200951void bsg_unregister_queue(struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200952{
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200953 struct bsg_class_device *bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200954
955 if (!bcd->class_dev)
956 return;
957
958 mutex_lock(&bsg_mutex);
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200959 sysfs_remove_link(&q->kobj, "bsg");
Jens Axboe3d6392c2007-07-09 12:38:05 +0200960 class_device_destroy(bsg_class, MKDEV(BSG_MAJOR, bcd->minor));
961 bcd->class_dev = NULL;
962 list_del_init(&bcd->list);
FUJITA Tomonori292b7f22007-03-28 13:29:58 +0200963 bsg_device_nr--;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200964 mutex_unlock(&bsg_mutex);
965}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +0200966EXPORT_SYMBOL_GPL(bsg_unregister_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200967
FUJITA Tomonori4cf07232007-03-30 11:19:39 +0200968int bsg_register_queue(struct request_queue *q, const char *name)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200969{
FUJITA Tomonori292b7f22007-03-28 13:29:58 +0200970 struct bsg_class_device *bcd, *__bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200971 dev_t dev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +0200972 int ret = -EMFILE;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +0200973 struct class_device *class_dev = NULL;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200974
975 /*
976 * we need a proper transport to send commands, not a stacked device
977 */
978 if (!q->request_fn)
979 return 0;
980
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200981 bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200982 memset(bcd, 0, sizeof(*bcd));
983 INIT_LIST_HEAD(&bcd->list);
984
985 mutex_lock(&bsg_mutex);
FUJITA Tomonori292b7f22007-03-28 13:29:58 +0200986 if (bsg_device_nr == BSG_MAX_DEVS) {
987 printk(KERN_ERR "bsg: too many bsg devices\n");
988 goto err;
989 }
990
991retry:
992 list_for_each_entry(__bcd, &bsg_class_list, list) {
993 if (__bcd->minor == bsg_minor_idx) {
994 bsg_minor_idx++;
995 if (bsg_minor_idx == BSG_MAX_DEVS)
996 bsg_minor_idx = 0;
997 goto retry;
998 }
999 }
1000
1001 bcd->minor = bsg_minor_idx++;
1002 if (bsg_minor_idx == BSG_MAX_DEVS)
1003 bsg_minor_idx = 0;
1004
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001005 bcd->queue = q;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001006 dev = MKDEV(BSG_MAJOR, bcd->minor);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001007 class_dev = class_device_create(bsg_class, NULL, dev, bcd->dev, "%s", name);
1008 if (IS_ERR(class_dev)) {
1009 ret = PTR_ERR(class_dev);
Jens Axboe264a0472007-01-23 16:30:17 +01001010 goto err;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001011 }
1012 bcd->class_dev = class_dev;
1013
Linus Torvaldsabce8912007-07-16 11:18:23 -07001014 if (q->kobj.sd) {
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001015 ret = sysfs_create_link(&q->kobj, &bcd->class_dev->kobj, "bsg");
1016 if (ret)
1017 goto err;
1018 }
1019
Jens Axboe3d6392c2007-07-09 12:38:05 +02001020 list_add_tail(&bcd->list, &bsg_class_list);
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001021 bsg_device_nr++;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001022
Jens Axboe3d6392c2007-07-09 12:38:05 +02001023 mutex_unlock(&bsg_mutex);
1024 return 0;
Jens Axboe264a0472007-01-23 16:30:17 +01001025err:
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001026 if (class_dev)
Jens Axboe264a0472007-01-23 16:30:17 +01001027 class_device_destroy(bsg_class, MKDEV(BSG_MAJOR, bcd->minor));
1028 mutex_unlock(&bsg_mutex);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001029 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001030}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +02001031EXPORT_SYMBOL_GPL(bsg_register_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001032
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001033static int bsg_add(struct class_device *cl_dev, struct class_interface *cl_intf)
1034{
1035 int ret;
1036 struct scsi_device *sdp = to_scsi_device(cl_dev->dev);
1037 struct request_queue *rq = sdp->request_queue;
1038
1039 if (rq->kobj.parent)
1040 ret = bsg_register_queue(rq, kobject_name(rq->kobj.parent));
1041 else
1042 ret = bsg_register_queue(rq, kobject_name(&sdp->sdev_gendev.kobj));
1043 return ret;
1044}
1045
1046static void bsg_remove(struct class_device *cl_dev, struct class_interface *cl_intf)
1047{
1048 bsg_unregister_queue(to_scsi_device(cl_dev->dev)->request_queue);
1049}
1050
1051static struct class_interface bsg_intf = {
1052 .add = bsg_add,
1053 .remove = bsg_remove,
1054};
1055
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001056static struct cdev bsg_cdev = {
1057 .kobj = {.name = "bsg", },
1058 .owner = THIS_MODULE,
1059};
1060
Jens Axboe3d6392c2007-07-09 12:38:05 +02001061static int __init bsg_init(void)
1062{
1063 int ret, i;
1064
Jens Axboe5309cb32007-01-23 16:24:41 +01001065 bsg_cmd_cachep = kmem_cache_create("bsg_cmd",
1066 sizeof(struct bsg_command), 0, 0, NULL, NULL);
1067 if (!bsg_cmd_cachep) {
1068 printk(KERN_ERR "bsg: failed creating slab cache\n");
1069 return -ENOMEM;
1070 }
1071
Jens Axboe3d6392c2007-07-09 12:38:05 +02001072 for (i = 0; i < BSG_LIST_SIZE; i++)
1073 INIT_HLIST_HEAD(&bsg_device_list[i]);
1074
1075 bsg_class = class_create(THIS_MODULE, "bsg");
Jens Axboe5309cb32007-01-23 16:24:41 +01001076 if (IS_ERR(bsg_class)) {
1077 kmem_cache_destroy(bsg_cmd_cachep);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001078 return PTR_ERR(bsg_class);
Jens Axboe5309cb32007-01-23 16:24:41 +01001079 }
Jens Axboe3d6392c2007-07-09 12:38:05 +02001080
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001081 ret = register_chrdev_region(MKDEV(BSG_MAJOR, 0), BSG_MAX_DEVS, "bsg");
Jens Axboe3d6392c2007-07-09 12:38:05 +02001082 if (ret) {
Jens Axboe5309cb32007-01-23 16:24:41 +01001083 kmem_cache_destroy(bsg_cmd_cachep);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001084 class_destroy(bsg_class);
1085 return ret;
1086 }
1087
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001088 cdev_init(&bsg_cdev, &bsg_fops);
1089 ret = cdev_add(&bsg_cdev, MKDEV(BSG_MAJOR, 0), BSG_MAX_DEVS);
1090 if (ret) {
1091 kmem_cache_destroy(bsg_cmd_cachep);
1092 class_destroy(bsg_class);
1093 unregister_chrdev_region(MKDEV(BSG_MAJOR, 0), BSG_MAX_DEVS);
1094 return ret;
1095 }
1096
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001097 ret = scsi_register_interface(&bsg_intf);
1098 if (ret) {
1099 printk(KERN_ERR "bsg: failed register scsi interface %d\n", ret);
1100 kmem_cache_destroy(bsg_cmd_cachep);
1101 class_destroy(bsg_class);
1102 unregister_chrdev(BSG_MAJOR, "bsg");
1103 return ret;
1104 }
1105
Jens Axboe3d6392c2007-07-09 12:38:05 +02001106 printk(KERN_INFO "%s loaded\n", bsg_version);
1107 return 0;
1108}
1109
1110MODULE_AUTHOR("Jens Axboe");
1111MODULE_DESCRIPTION("Block layer SGSI generic (sg) driver");
1112MODULE_LICENSE("GPL");
1113
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001114device_initcall(bsg_init);