Commit | Line | Data |
---|---|---|
3d6392cf | 1 | /* |
0c6a89ba | 2 | * bsg.c - block layer implementation of the sg v4 interface |
3d6392cf JA |
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 | */ | |
3d6392cf JA |
12 | #include <linux/module.h> |
13 | #include <linux/init.h> | |
14 | #include <linux/file.h> | |
15 | #include <linux/blkdev.h> | |
16 | #include <linux/poll.h> | |
17 | #include <linux/cdev.h> | |
18 | #include <linux/percpu.h> | |
19 | #include <linux/uio.h> | |
598443a2 | 20 | #include <linux/idr.h> |
3d6392cf | 21 | #include <linux/bsg.h> |
75bd2ef1 | 22 | #include <linux/smp_lock.h> |
3d6392cf JA |
23 | |
24 | #include <scsi/scsi.h> | |
25 | #include <scsi/scsi_ioctl.h> | |
26 | #include <scsi/scsi_cmnd.h> | |
4e2872d6 FT |
27 | #include <scsi/scsi_device.h> |
28 | #include <scsi/scsi_driver.h> | |
3d6392cf JA |
29 | #include <scsi/sg.h> |
30 | ||
0ed081ce FT |
31 | #define BSG_DESCRIPTION "Block layer SCSI generic (bsg) driver" |
32 | #define BSG_VERSION "0.4" | |
3d6392cf | 33 | |
3d6392cf | 34 | struct bsg_device { |
165125e1 | 35 | struct request_queue *queue; |
3d6392cf JA |
36 | spinlock_t lock; |
37 | struct list_head busy_list; | |
38 | struct list_head done_list; | |
39 | struct hlist_node dev_list; | |
40 | atomic_t ref_count; | |
3d6392cf JA |
41 | int queued_cmds; |
42 | int done_cmds; | |
3d6392cf JA |
43 | wait_queue_head_t wq_done; |
44 | wait_queue_head_t wq_free; | |
3ada8b7e | 45 | char name[20]; |
3d6392cf JA |
46 | int max_queue; |
47 | unsigned long flags; | |
48 | }; | |
49 | ||
50 | enum { | |
51 | BSG_F_BLOCK = 1, | |
3d6392cf JA |
52 | }; |
53 | ||
5309cb38 | 54 | #define BSG_DEFAULT_CMDS 64 |
292b7f27 | 55 | #define BSG_MAX_DEVS 32768 |
3d6392cf JA |
56 | |
57 | #undef BSG_DEBUG | |
58 | ||
59 | #ifdef BSG_DEBUG | |
24c03d47 | 60 | #define dprintk(fmt, args...) printk(KERN_ERR "%s: " fmt, __func__, ##args) |
3d6392cf JA |
61 | #else |
62 | #define dprintk(fmt, args...) | |
63 | #endif | |
64 | ||
3d6392cf | 65 | static DEFINE_MUTEX(bsg_mutex); |
598443a2 | 66 | static DEFINE_IDR(bsg_minor_idr); |
3d6392cf | 67 | |
25fd1643 | 68 | #define BSG_LIST_ARRAY_SIZE 8 |
25fd1643 | 69 | static struct hlist_head bsg_device_list[BSG_LIST_ARRAY_SIZE]; |
3d6392cf JA |
70 | |
71 | static struct class *bsg_class; | |
46f6ef4a | 72 | static int bsg_major; |
3d6392cf | 73 | |
5309cb38 JA |
74 | static struct kmem_cache *bsg_cmd_cachep; |
75 | ||
3d6392cf JA |
76 | /* |
77 | * our internal command type | |
78 | */ | |
79 | struct bsg_command { | |
80 | struct bsg_device *bd; | |
81 | struct list_head list; | |
82 | struct request *rq; | |
83 | struct bio *bio; | |
2c9ecdf4 | 84 | struct bio *bidi_bio; |
3d6392cf | 85 | int err; |
70e36ece | 86 | struct sg_io_v4 hdr; |
3d6392cf JA |
87 | char sense[SCSI_SENSE_BUFFERSIZE]; |
88 | }; | |
89 | ||
90 | static void bsg_free_command(struct bsg_command *bc) | |
91 | { | |
92 | struct bsg_device *bd = bc->bd; | |
3d6392cf JA |
93 | unsigned long flags; |
94 | ||
5309cb38 | 95 | kmem_cache_free(bsg_cmd_cachep, bc); |
3d6392cf JA |
96 | |
97 | spin_lock_irqsave(&bd->lock, flags); | |
98 | bd->queued_cmds--; | |
3d6392cf JA |
99 | spin_unlock_irqrestore(&bd->lock, flags); |
100 | ||
101 | wake_up(&bd->wq_free); | |
102 | } | |
103 | ||
e7d72173 | 104 | static struct bsg_command *bsg_alloc_command(struct bsg_device *bd) |
3d6392cf | 105 | { |
e7d72173 | 106 | struct bsg_command *bc = ERR_PTR(-EINVAL); |
3d6392cf JA |
107 | |
108 | spin_lock_irq(&bd->lock); | |
109 | ||
110 | if (bd->queued_cmds >= bd->max_queue) | |
111 | goto out; | |
112 | ||
3d6392cf | 113 | bd->queued_cmds++; |
3d6392cf JA |
114 | spin_unlock_irq(&bd->lock); |
115 | ||
25fd1643 | 116 | bc = kmem_cache_zalloc(bsg_cmd_cachep, GFP_KERNEL); |
5309cb38 JA |
117 | if (unlikely(!bc)) { |
118 | spin_lock_irq(&bd->lock); | |
7e75d730 | 119 | bd->queued_cmds--; |
e7d72173 | 120 | bc = ERR_PTR(-ENOMEM); |
7e75d730 | 121 | goto out; |
5309cb38 JA |
122 | } |
123 | ||
3d6392cf JA |
124 | bc->bd = bd; |
125 | INIT_LIST_HEAD(&bc->list); | |
5309cb38 | 126 | dprintk("%s: returning free cmd %p\n", bd->name, bc); |
3d6392cf JA |
127 | return bc; |
128 | out: | |
3d6392cf JA |
129 | spin_unlock_irq(&bd->lock); |
130 | return bc; | |
131 | } | |
132 | ||
1c1133e1 | 133 | static inline struct hlist_head *bsg_dev_idx_hash(int index) |
3d6392cf | 134 | { |
1c1133e1 | 135 | return &bsg_device_list[index & (BSG_LIST_ARRAY_SIZE - 1)]; |
3d6392cf JA |
136 | } |
137 | ||
25fd1643 | 138 | static int bsg_io_schedule(struct bsg_device *bd) |
3d6392cf JA |
139 | { |
140 | DEFINE_WAIT(wait); | |
141 | int ret = 0; | |
142 | ||
143 | spin_lock_irq(&bd->lock); | |
144 | ||
145 | BUG_ON(bd->done_cmds > bd->queued_cmds); | |
146 | ||
147 | /* | |
148 | * -ENOSPC or -ENODATA? I'm going for -ENODATA, meaning "I have no | |
149 | * work to do", even though we return -ENOSPC after this same test | |
150 | * during bsg_write() -- there, it means our buffer can't have more | |
151 | * bsg_commands added to it, thus has no space left. | |
152 | */ | |
153 | if (bd->done_cmds == bd->queued_cmds) { | |
154 | ret = -ENODATA; | |
155 | goto unlock; | |
156 | } | |
157 | ||
158 | if (!test_bit(BSG_F_BLOCK, &bd->flags)) { | |
159 | ret = -EAGAIN; | |
160 | goto unlock; | |
161 | } | |
162 | ||
25fd1643 | 163 | prepare_to_wait(&bd->wq_done, &wait, TASK_UNINTERRUPTIBLE); |
3d6392cf JA |
164 | spin_unlock_irq(&bd->lock); |
165 | io_schedule(); | |
166 | finish_wait(&bd->wq_done, &wait); | |
167 | ||
3d6392cf JA |
168 | return ret; |
169 | unlock: | |
170 | spin_unlock_irq(&bd->lock); | |
171 | return ret; | |
172 | } | |
173 | ||
165125e1 | 174 | static int blk_fill_sgv4_hdr_rq(struct request_queue *q, struct request *rq, |
abf54393 | 175 | struct sg_io_v4 *hdr, struct bsg_device *bd, |
aeb5d727 | 176 | fmode_t has_write_perm) |
70e36ece | 177 | { |
9f5de6b1 FT |
178 | if (hdr->request_len > BLK_MAX_CDB) { |
179 | rq->cmd = kzalloc(hdr->request_len, GFP_KERNEL); | |
180 | if (!rq->cmd) | |
181 | return -ENOMEM; | |
182 | } | |
70e36ece FT |
183 | |
184 | if (copy_from_user(rq->cmd, (void *)(unsigned long)hdr->request, | |
185 | hdr->request_len)) | |
186 | return -EFAULT; | |
15d10b61 FT |
187 | |
188 | if (hdr->subprotocol == BSG_SUB_PROTOCOL_SCSI_CMD) { | |
abf54393 | 189 | if (blk_verify_command(&q->cmd_filter, rq->cmd, has_write_perm)) |
15d10b61 FT |
190 | return -EPERM; |
191 | } else if (!capable(CAP_SYS_RAWIO)) | |
70e36ece FT |
192 | return -EPERM; |
193 | ||
194 | /* | |
195 | * fill in request structure | |
196 | */ | |
197 | rq->cmd_len = hdr->request_len; | |
198 | rq->cmd_type = REQ_TYPE_BLOCK_PC; | |
199 | ||
200 | rq->timeout = (hdr->timeout * HZ) / 1000; | |
201 | if (!rq->timeout) | |
202 | rq->timeout = q->sg_timeout; | |
203 | if (!rq->timeout) | |
204 | rq->timeout = BLK_DEFAULT_SG_TIMEOUT; | |
f2f1fa78 LT |
205 | if (rq->timeout < BLK_MIN_SG_TIMEOUT) |
206 | rq->timeout = BLK_MIN_SG_TIMEOUT; | |
70e36ece FT |
207 | |
208 | return 0; | |
209 | } | |
210 | ||
3d6392cf | 211 | /* |
70e36ece | 212 | * Check if sg_io_v4 from user is allowed and valid |
3d6392cf JA |
213 | */ |
214 | static int | |
165125e1 | 215 | bsg_validate_sgv4_hdr(struct request_queue *q, struct sg_io_v4 *hdr, int *rw) |
3d6392cf | 216 | { |
15d10b61 FT |
217 | int ret = 0; |
218 | ||
70e36ece | 219 | if (hdr->guard != 'Q') |
3d6392cf | 220 | return -EINVAL; |
70e36ece FT |
221 | if (hdr->dout_xfer_len > (q->max_sectors << 9) || |
222 | hdr->din_xfer_len > (q->max_sectors << 9)) | |
3d6392cf JA |
223 | return -EIO; |
224 | ||
15d10b61 FT |
225 | switch (hdr->protocol) { |
226 | case BSG_PROTOCOL_SCSI: | |
227 | switch (hdr->subprotocol) { | |
228 | case BSG_SUB_PROTOCOL_SCSI_CMD: | |
229 | case BSG_SUB_PROTOCOL_SCSI_TRANSPORT: | |
230 | break; | |
231 | default: | |
232 | ret = -EINVAL; | |
233 | } | |
234 | break; | |
235 | default: | |
236 | ret = -EINVAL; | |
237 | } | |
70e36ece | 238 | |
70e36ece | 239 | *rw = hdr->dout_xfer_len ? WRITE : READ; |
15d10b61 | 240 | return ret; |
3d6392cf JA |
241 | } |
242 | ||
243 | /* | |
70e36ece | 244 | * map sg_io_v4 to a request. |
3d6392cf JA |
245 | */ |
246 | static struct request * | |
aeb5d727 | 247 | bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t has_write_perm) |
3d6392cf | 248 | { |
165125e1 | 249 | struct request_queue *q = bd->queue; |
2c9ecdf4 | 250 | struct request *rq, *next_rq = NULL; |
25fd1643 | 251 | int ret, rw; |
70e36ece FT |
252 | unsigned int dxfer_len; |
253 | void *dxferp = NULL; | |
3d6392cf | 254 | |
70e36ece FT |
255 | dprintk("map hdr %llx/%u %llx/%u\n", (unsigned long long) hdr->dout_xferp, |
256 | hdr->dout_xfer_len, (unsigned long long) hdr->din_xferp, | |
257 | hdr->din_xfer_len); | |
3d6392cf | 258 | |
70e36ece | 259 | ret = bsg_validate_sgv4_hdr(q, hdr, &rw); |
3d6392cf JA |
260 | if (ret) |
261 | return ERR_PTR(ret); | |
262 | ||
263 | /* | |
264 | * map scatter-gather elements seperately and string them to request | |
265 | */ | |
266 | rq = blk_get_request(q, rw, GFP_KERNEL); | |
2c9ecdf4 FT |
267 | if (!rq) |
268 | return ERR_PTR(-ENOMEM); | |
abf54393 | 269 | ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, bd, has_write_perm); |
2c9ecdf4 FT |
270 | if (ret) |
271 | goto out; | |
272 | ||
273 | if (rw == WRITE && hdr->din_xfer_len) { | |
274 | if (!test_bit(QUEUE_FLAG_BIDI, &q->queue_flags)) { | |
275 | ret = -EOPNOTSUPP; | |
276 | goto out; | |
277 | } | |
278 | ||
279 | next_rq = blk_get_request(q, READ, GFP_KERNEL); | |
280 | if (!next_rq) { | |
281 | ret = -ENOMEM; | |
282 | goto out; | |
283 | } | |
284 | rq->next_rq = next_rq; | |
40f62028 | 285 | next_rq->cmd_type = rq->cmd_type; |
2c9ecdf4 FT |
286 | |
287 | dxferp = (void*)(unsigned long)hdr->din_xferp; | |
152e283f FT |
288 | ret = blk_rq_map_user(q, next_rq, NULL, dxferp, |
289 | hdr->din_xfer_len, GFP_KERNEL); | |
2c9ecdf4 FT |
290 | if (ret) |
291 | goto out; | |
3d6392cf JA |
292 | } |
293 | ||
70e36ece FT |
294 | if (hdr->dout_xfer_len) { |
295 | dxfer_len = hdr->dout_xfer_len; | |
296 | dxferp = (void*)(unsigned long)hdr->dout_xferp; | |
297 | } else if (hdr->din_xfer_len) { | |
298 | dxfer_len = hdr->din_xfer_len; | |
299 | dxferp = (void*)(unsigned long)hdr->din_xferp; | |
300 | } else | |
301 | dxfer_len = 0; | |
302 | ||
303 | if (dxfer_len) { | |
152e283f FT |
304 | ret = blk_rq_map_user(q, rq, NULL, dxferp, dxfer_len, |
305 | GFP_KERNEL); | |
2c9ecdf4 FT |
306 | if (ret) |
307 | goto out; | |
3d6392cf | 308 | } |
3d6392cf | 309 | return rq; |
2c9ecdf4 | 310 | out: |
9f5de6b1 FT |
311 | if (rq->cmd != rq->__cmd) |
312 | kfree(rq->cmd); | |
2c9ecdf4 FT |
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); | |
3d6392cf JA |
319 | } |
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 | */ | |
325 | static 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 | ||
5309cb38 JA |
331 | dprintk("%s: finished rq %p bc %p, bio %p stat %d\n", |
332 | bd->name, rq, bc, bc->bio, uptodate); | |
3d6392cf JA |
333 | |
334 | bc->hdr.duration = jiffies_to_msecs(jiffies - bc->hdr.duration); | |
335 | ||
336 | spin_lock_irqsave(&bd->lock, flags); | |
25fd1643 JA |
337 | list_move_tail(&bc->list, &bd->done_list); |
338 | bd->done_cmds++; | |
3d6392cf | 339 | spin_unlock_irqrestore(&bd->lock, flags); |
25fd1643 JA |
340 | |
341 | wake_up(&bd->wq_done); | |
3d6392cf JA |
342 | } |
343 | ||
344 | /* | |
345 | * do final setup of a 'bc' and submit the matching 'rq' to the block | |
346 | * layer for io | |
347 | */ | |
165125e1 | 348 | static void bsg_add_command(struct bsg_device *bd, struct request_queue *q, |
3d6392cf JA |
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; | |
2c9ecdf4 FT |
359 | if (rq->next_rq) |
360 | bc->bidi_bio = rq->next_rq->bio; | |
3d6392cf JA |
361 | 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; | |
d351af01 | 369 | blk_execute_rq_nowait(q, NULL, rq, 1, bsg_rq_end_io); |
3d6392cf JA |
370 | } |
371 | ||
25fd1643 | 372 | static struct bsg_command *bsg_next_done_cmd(struct bsg_device *bd) |
3d6392cf JA |
373 | { |
374 | struct bsg_command *bc = NULL; | |
375 | ||
376 | spin_lock_irq(&bd->lock); | |
377 | if (bd->done_cmds) { | |
43ac9e62 | 378 | bc = list_first_entry(&bd->done_list, struct bsg_command, list); |
25fd1643 JA |
379 | list_del(&bc->list); |
380 | bd->done_cmds--; | |
3d6392cf JA |
381 | } |
382 | spin_unlock_irq(&bd->lock); | |
383 | ||
384 | return bc; | |
385 | } | |
386 | ||
387 | /* | |
388 | * Get a finished command from the done list | |
389 | */ | |
e7d72173 | 390 | static struct bsg_command *bsg_get_done_cmd(struct bsg_device *bd) |
3d6392cf JA |
391 | { |
392 | struct bsg_command *bc; | |
393 | int ret; | |
394 | ||
395 | do { | |
396 | bc = bsg_next_done_cmd(bd); | |
397 | if (bc) | |
398 | break; | |
399 | ||
e7d72173 FT |
400 | 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); | |
3d6392cf | 406 | if (ret) { |
e7d72173 | 407 | bc = ERR_PTR(-ERESTARTSYS); |
3d6392cf JA |
408 | break; |
409 | } | |
410 | } while (1); | |
411 | ||
412 | dprintk("%s: returning done %p\n", bd->name, bc); | |
413 | ||
414 | return bc; | |
415 | } | |
416 | ||
70e36ece | 417 | static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr, |
2c9ecdf4 | 418 | struct bio *bio, struct bio *bidi_bio) |
70e36ece FT |
419 | { |
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; | |
70e36ece FT |
432 | hdr->response_len = 0; |
433 | ||
434 | if (rq->sense_len && hdr->response) { | |
25fd1643 JA |
435 | int len = min_t(unsigned int, hdr->max_response_len, |
436 | rq->sense_len); | |
70e36ece FT |
437 | |
438 | ret = copy_to_user((void*)(unsigned long)hdr->response, | |
439 | rq->sense, len); | |
440 | if (!ret) | |
441 | hdr->response_len = len; | |
442 | else | |
443 | ret = -EFAULT; | |
444 | } | |
445 | ||
2c9ecdf4 | 446 | if (rq->next_rq) { |
7a85f889 FT |
447 | hdr->dout_resid = rq->data_len; |
448 | hdr->din_resid = rq->next_rq->data_len; | |
2c9ecdf4 FT |
449 | blk_rq_unmap_user(bidi_bio); |
450 | blk_put_request(rq->next_rq); | |
0c6a89ba | 451 | } else if (rq_data_dir(rq) == READ) |
7a85f889 | 452 | hdr->din_resid = rq->data_len; |
0c6a89ba | 453 | else |
7a85f889 | 454 | hdr->dout_resid = rq->data_len; |
2c9ecdf4 | 455 | |
2d507a01 JB |
456 | /* |
457 | * If the request generated a negative error number, return it | |
458 | * (providing we aren't already returning an error); if it's | |
459 | * just a protocol response (i.e. non negative), that gets | |
460 | * processed above. | |
461 | */ | |
462 | if (!ret && rq->errors < 0) | |
463 | ret = rq->errors; | |
464 | ||
70e36ece | 465 | blk_rq_unmap_user(bio); |
9f5de6b1 FT |
466 | if (rq->cmd != rq->__cmd) |
467 | kfree(rq->cmd); | |
70e36ece FT |
468 | blk_put_request(rq); |
469 | ||
470 | return ret; | |
471 | } | |
472 | ||
3d6392cf JA |
473 | static int bsg_complete_all_commands(struct bsg_device *bd) |
474 | { | |
475 | struct bsg_command *bc; | |
476 | int ret, tret; | |
477 | ||
478 | dprintk("%s: entered\n", bd->name); | |
479 | ||
3d6392cf JA |
480 | /* |
481 | * wait for all commands to complete | |
482 | */ | |
483 | ret = 0; | |
484 | do { | |
25fd1643 | 485 | ret = bsg_io_schedule(bd); |
3d6392cf JA |
486 | /* |
487 | * look for -ENODATA specifically -- we'll sometimes get | |
488 | * -ERESTARTSYS when we've taken a signal, but we can't | |
489 | * return until we're done freeing the queue, so ignore | |
490 | * it. The signal will get handled when we're done freeing | |
491 | * the bsg_device. | |
492 | */ | |
493 | } while (ret != -ENODATA); | |
494 | ||
495 | /* | |
496 | * discard done commands | |
497 | */ | |
498 | ret = 0; | |
499 | do { | |
e7d72173 FT |
500 | spin_lock_irq(&bd->lock); |
501 | if (!bd->queued_cmds) { | |
502 | spin_unlock_irq(&bd->lock); | |
3d6392cf JA |
503 | break; |
504 | } | |
efba1a31 | 505 | spin_unlock_irq(&bd->lock); |
3d6392cf | 506 | |
e7d72173 FT |
507 | bc = bsg_get_done_cmd(bd); |
508 | if (IS_ERR(bc)) | |
509 | break; | |
510 | ||
2c9ecdf4 FT |
511 | tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio, |
512 | bc->bidi_bio); | |
3d6392cf JA |
513 | if (!ret) |
514 | ret = tret; | |
515 | ||
516 | bsg_free_command(bc); | |
517 | } while (1); | |
518 | ||
519 | return ret; | |
520 | } | |
521 | ||
25fd1643 | 522 | static int |
e7d72173 FT |
523 | __bsg_read(char __user *buf, size_t count, struct bsg_device *bd, |
524 | const struct iovec *iov, ssize_t *bytes_read) | |
3d6392cf JA |
525 | { |
526 | struct bsg_command *bc; | |
527 | int nr_commands, ret; | |
528 | ||
70e36ece | 529 | if (count % sizeof(struct sg_io_v4)) |
3d6392cf JA |
530 | return -EINVAL; |
531 | ||
532 | ret = 0; | |
70e36ece | 533 | nr_commands = count / sizeof(struct sg_io_v4); |
3d6392cf | 534 | while (nr_commands) { |
e7d72173 | 535 | bc = bsg_get_done_cmd(bd); |
3d6392cf JA |
536 | if (IS_ERR(bc)) { |
537 | ret = PTR_ERR(bc); | |
538 | break; | |
539 | } | |
540 | ||
541 | /* | |
542 | * this is the only case where we need to copy data back | |
543 | * after completing the request. so do that here, | |
544 | * bsg_complete_work() cannot do that for us | |
545 | */ | |
2c9ecdf4 FT |
546 | ret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio, |
547 | bc->bidi_bio); | |
3d6392cf | 548 | |
25fd1643 | 549 | if (copy_to_user(buf, &bc->hdr, sizeof(bc->hdr))) |
3d6392cf JA |
550 | ret = -EFAULT; |
551 | ||
552 | bsg_free_command(bc); | |
553 | ||
554 | if (ret) | |
555 | break; | |
556 | ||
70e36ece FT |
557 | buf += sizeof(struct sg_io_v4); |
558 | *bytes_read += sizeof(struct sg_io_v4); | |
3d6392cf JA |
559 | nr_commands--; |
560 | } | |
561 | ||
562 | return ret; | |
563 | } | |
564 | ||
565 | static inline void bsg_set_block(struct bsg_device *bd, struct file *file) | |
566 | { | |
567 | if (file->f_flags & O_NONBLOCK) | |
568 | clear_bit(BSG_F_BLOCK, &bd->flags); | |
569 | else | |
570 | set_bit(BSG_F_BLOCK, &bd->flags); | |
571 | } | |
572 | ||
25fd1643 JA |
573 | /* |
574 | * Check if the error is a "real" error that we should return. | |
575 | */ | |
3d6392cf JA |
576 | static inline int err_block_err(int ret) |
577 | { | |
578 | if (ret && ret != -ENOSPC && ret != -ENODATA && ret != -EAGAIN) | |
579 | return 1; | |
580 | ||
581 | return 0; | |
582 | } | |
583 | ||
584 | static ssize_t | |
585 | bsg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
586 | { | |
587 | struct bsg_device *bd = file->private_data; | |
588 | int ret; | |
589 | ssize_t bytes_read; | |
590 | ||
9e69fbb5 | 591 | dprintk("%s: read %Zd bytes\n", bd->name, count); |
3d6392cf JA |
592 | |
593 | bsg_set_block(bd, file); | |
0b07de85 | 594 | |
3d6392cf | 595 | bytes_read = 0; |
e7d72173 | 596 | ret = __bsg_read(buf, count, bd, NULL, &bytes_read); |
3d6392cf JA |
597 | *ppos = bytes_read; |
598 | ||
599 | if (!bytes_read || (bytes_read && err_block_err(ret))) | |
600 | bytes_read = ret; | |
601 | ||
602 | return bytes_read; | |
603 | } | |
604 | ||
25fd1643 | 605 | static int __bsg_write(struct bsg_device *bd, const char __user *buf, |
aeb5d727 AV |
606 | size_t count, ssize_t *bytes_written, |
607 | fmode_t has_write_perm) | |
3d6392cf JA |
608 | { |
609 | struct bsg_command *bc; | |
610 | struct request *rq; | |
611 | int ret, nr_commands; | |
612 | ||
70e36ece | 613 | if (count % sizeof(struct sg_io_v4)) |
3d6392cf JA |
614 | return -EINVAL; |
615 | ||
70e36ece | 616 | nr_commands = count / sizeof(struct sg_io_v4); |
3d6392cf JA |
617 | rq = NULL; |
618 | bc = NULL; | |
619 | ret = 0; | |
620 | while (nr_commands) { | |
165125e1 | 621 | struct request_queue *q = bd->queue; |
3d6392cf | 622 | |
e7d72173 | 623 | bc = bsg_alloc_command(bd); |
3d6392cf JA |
624 | if (IS_ERR(bc)) { |
625 | ret = PTR_ERR(bc); | |
626 | bc = NULL; | |
627 | break; | |
628 | } | |
629 | ||
3d6392cf JA |
630 | if (copy_from_user(&bc->hdr, buf, sizeof(bc->hdr))) { |
631 | ret = -EFAULT; | |
632 | break; | |
633 | } | |
634 | ||
635 | /* | |
636 | * get a request, fill in the blanks, and add to request queue | |
637 | */ | |
abf54393 | 638 | rq = bsg_map_hdr(bd, &bc->hdr, has_write_perm); |
3d6392cf JA |
639 | if (IS_ERR(rq)) { |
640 | ret = PTR_ERR(rq); | |
641 | rq = NULL; | |
642 | break; | |
643 | } | |
644 | ||
645 | bsg_add_command(bd, q, bc, rq); | |
646 | bc = NULL; | |
647 | rq = NULL; | |
648 | nr_commands--; | |
70e36ece | 649 | buf += sizeof(struct sg_io_v4); |
25fd1643 | 650 | *bytes_written += sizeof(struct sg_io_v4); |
3d6392cf JA |
651 | } |
652 | ||
3d6392cf JA |
653 | if (bc) |
654 | bsg_free_command(bc); | |
655 | ||
656 | return ret; | |
657 | } | |
658 | ||
659 | static ssize_t | |
660 | bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) | |
661 | { | |
662 | struct bsg_device *bd = file->private_data; | |
25fd1643 | 663 | ssize_t bytes_written; |
3d6392cf JA |
664 | int ret; |
665 | ||
9e69fbb5 | 666 | dprintk("%s: write %Zd bytes\n", bd->name, count); |
3d6392cf JA |
667 | |
668 | bsg_set_block(bd, file); | |
3d6392cf | 669 | |
25fd1643 | 670 | bytes_written = 0; |
abf54393 FT |
671 | ret = __bsg_write(bd, buf, count, &bytes_written, |
672 | file->f_mode & FMODE_WRITE); | |
673 | ||
25fd1643 | 674 | *ppos = bytes_written; |
3d6392cf JA |
675 | |
676 | /* | |
677 | * return bytes written on non-fatal errors | |
678 | */ | |
25fd1643 JA |
679 | if (!bytes_written || (bytes_written && err_block_err(ret))) |
680 | bytes_written = ret; | |
3d6392cf | 681 | |
25fd1643 JA |
682 | dprintk("%s: returning %Zd\n", bd->name, bytes_written); |
683 | return bytes_written; | |
3d6392cf JA |
684 | } |
685 | ||
3d6392cf JA |
686 | static struct bsg_device *bsg_alloc_device(void) |
687 | { | |
3d6392cf | 688 | struct bsg_device *bd; |
3d6392cf JA |
689 | |
690 | bd = kzalloc(sizeof(struct bsg_device), GFP_KERNEL); | |
691 | if (unlikely(!bd)) | |
692 | return NULL; | |
693 | ||
694 | spin_lock_init(&bd->lock); | |
695 | ||
5309cb38 | 696 | bd->max_queue = BSG_DEFAULT_CMDS; |
3d6392cf JA |
697 | |
698 | INIT_LIST_HEAD(&bd->busy_list); | |
699 | INIT_LIST_HEAD(&bd->done_list); | |
700 | INIT_HLIST_NODE(&bd->dev_list); | |
701 | ||
702 | init_waitqueue_head(&bd->wq_free); | |
703 | init_waitqueue_head(&bd->wq_done); | |
704 | return bd; | |
3d6392cf JA |
705 | } |
706 | ||
97f46ae4 FT |
707 | static void bsg_kref_release_function(struct kref *kref) |
708 | { | |
709 | struct bsg_class_device *bcd = | |
710 | container_of(kref, struct bsg_class_device, ref); | |
8df5fc04 | 711 | struct device *parent = bcd->parent; |
97f46ae4 FT |
712 | |
713 | if (bcd->release) | |
714 | bcd->release(bcd->parent); | |
715 | ||
8df5fc04 | 716 | put_device(parent); |
97f46ae4 FT |
717 | } |
718 | ||
3d6392cf JA |
719 | static int bsg_put_device(struct bsg_device *bd) |
720 | { | |
97f46ae4 FT |
721 | int ret = 0, do_free; |
722 | struct request_queue *q = bd->queue; | |
3d6392cf JA |
723 | |
724 | mutex_lock(&bsg_mutex); | |
725 | ||
97f46ae4 | 726 | do_free = atomic_dec_and_test(&bd->ref_count); |
3f27e3ed FT |
727 | if (!do_free) { |
728 | mutex_unlock(&bsg_mutex); | |
3d6392cf | 729 | goto out; |
3f27e3ed FT |
730 | } |
731 | ||
732 | hlist_del(&bd->dev_list); | |
733 | mutex_unlock(&bsg_mutex); | |
3d6392cf JA |
734 | |
735 | dprintk("%s: tearing down\n", bd->name); | |
736 | ||
737 | /* | |
738 | * close can always block | |
739 | */ | |
740 | set_bit(BSG_F_BLOCK, &bd->flags); | |
741 | ||
742 | /* | |
743 | * correct error detection baddies here again. it's the responsibility | |
744 | * of the app to properly reap commands before close() if it wants | |
745 | * fool-proof error detection | |
746 | */ | |
747 | ret = bsg_complete_all_commands(bd); | |
748 | ||
5309cb38 | 749 | kfree(bd); |
3d6392cf | 750 | out: |
97f46ae4 FT |
751 | kref_put(&q->bsg_dev.ref, bsg_kref_release_function); |
752 | if (do_free) | |
753 | blk_put_queue(q); | |
3d6392cf JA |
754 | return ret; |
755 | } | |
756 | ||
757 | static struct bsg_device *bsg_add_device(struct inode *inode, | |
d351af01 | 758 | struct request_queue *rq, |
3d6392cf JA |
759 | struct file *file) |
760 | { | |
25fd1643 | 761 | struct bsg_device *bd; |
c3ff1b90 | 762 | int ret; |
3d6392cf JA |
763 | #ifdef BSG_DEBUG |
764 | unsigned char buf[32]; | |
765 | #endif | |
c3ff1b90 FT |
766 | ret = blk_get_queue(rq); |
767 | if (ret) | |
768 | return ERR_PTR(-ENXIO); | |
3d6392cf JA |
769 | |
770 | bd = bsg_alloc_device(); | |
c3ff1b90 FT |
771 | if (!bd) { |
772 | blk_put_queue(rq); | |
3d6392cf | 773 | return ERR_PTR(-ENOMEM); |
c3ff1b90 | 774 | } |
3d6392cf | 775 | |
d351af01 | 776 | bd->queue = rq; |
0b07de85 | 777 | |
3d6392cf JA |
778 | bsg_set_block(bd, file); |
779 | ||
780 | atomic_set(&bd->ref_count, 1); | |
3d6392cf | 781 | mutex_lock(&bsg_mutex); |
842ea771 | 782 | hlist_add_head(&bd->dev_list, bsg_dev_idx_hash(iminor(inode))); |
3d6392cf | 783 | |
3ada8b7e | 784 | strncpy(bd->name, dev_name(rq->bsg_dev.class_dev), sizeof(bd->name) - 1); |
3d6392cf | 785 | dprintk("bound to <%s>, max queue %d\n", |
9e69fbb5 | 786 | format_dev_t(buf, inode->i_rdev), bd->max_queue); |
3d6392cf JA |
787 | |
788 | mutex_unlock(&bsg_mutex); | |
789 | return bd; | |
790 | } | |
791 | ||
842ea771 | 792 | static struct bsg_device *__bsg_get_device(int minor, struct request_queue *q) |
3d6392cf | 793 | { |
43ac9e62 | 794 | struct bsg_device *bd; |
3d6392cf JA |
795 | struct hlist_node *entry; |
796 | ||
797 | mutex_lock(&bsg_mutex); | |
798 | ||
43ac9e62 | 799 | hlist_for_each_entry(bd, entry, bsg_dev_idx_hash(minor), dev_list) { |
842ea771 | 800 | if (bd->queue == q) { |
3d6392cf | 801 | atomic_inc(&bd->ref_count); |
43ac9e62 | 802 | goto found; |
3d6392cf | 803 | } |
3d6392cf | 804 | } |
43ac9e62 FT |
805 | bd = NULL; |
806 | found: | |
3d6392cf JA |
807 | mutex_unlock(&bsg_mutex); |
808 | return bd; | |
809 | } | |
810 | ||
811 | static struct bsg_device *bsg_get_device(struct inode *inode, struct file *file) | |
812 | { | |
598443a2 FT |
813 | struct bsg_device *bd; |
814 | struct bsg_class_device *bcd; | |
3d6392cf | 815 | |
3d6392cf JA |
816 | /* |
817 | * find the class device | |
818 | */ | |
3d6392cf | 819 | mutex_lock(&bsg_mutex); |
598443a2 | 820 | bcd = idr_find(&bsg_minor_idr, iminor(inode)); |
d45ac4fa | 821 | if (bcd) |
97f46ae4 | 822 | kref_get(&bcd->ref); |
3d6392cf JA |
823 | mutex_unlock(&bsg_mutex); |
824 | ||
825 | if (!bcd) | |
826 | return ERR_PTR(-ENODEV); | |
827 | ||
842ea771 | 828 | bd = __bsg_get_device(iminor(inode), bcd->queue); |
d45ac4fa FT |
829 | if (bd) |
830 | return bd; | |
831 | ||
832 | bd = bsg_add_device(inode, bcd->queue, file); | |
833 | if (IS_ERR(bd)) | |
97f46ae4 | 834 | kref_put(&bcd->ref, bsg_kref_release_function); |
d45ac4fa FT |
835 | |
836 | return bd; | |
3d6392cf JA |
837 | } |
838 | ||
839 | static int bsg_open(struct inode *inode, struct file *file) | |
840 | { | |
75bd2ef1 JC |
841 | struct bsg_device *bd; |
842 | ||
843 | lock_kernel(); | |
844 | bd = bsg_get_device(inode, file); | |
845 | unlock_kernel(); | |
3d6392cf JA |
846 | |
847 | if (IS_ERR(bd)) | |
848 | return PTR_ERR(bd); | |
849 | ||
850 | file->private_data = bd; | |
851 | return 0; | |
852 | } | |
853 | ||
854 | static int bsg_release(struct inode *inode, struct file *file) | |
855 | { | |
856 | struct bsg_device *bd = file->private_data; | |
857 | ||
858 | file->private_data = NULL; | |
859 | return bsg_put_device(bd); | |
860 | } | |
861 | ||
862 | static unsigned int bsg_poll(struct file *file, poll_table *wait) | |
863 | { | |
864 | struct bsg_device *bd = file->private_data; | |
865 | unsigned int mask = 0; | |
866 | ||
867 | poll_wait(file, &bd->wq_done, wait); | |
868 | poll_wait(file, &bd->wq_free, wait); | |
869 | ||
870 | spin_lock_irq(&bd->lock); | |
871 | if (!list_empty(&bd->done_list)) | |
872 | mask |= POLLIN | POLLRDNORM; | |
873 | if (bd->queued_cmds >= bd->max_queue) | |
874 | mask |= POLLOUT; | |
875 | spin_unlock_irq(&bd->lock); | |
876 | ||
877 | return mask; | |
878 | } | |
879 | ||
25fd1643 | 880 | static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
3d6392cf JA |
881 | { |
882 | struct bsg_device *bd = file->private_data; | |
883 | int __user *uarg = (int __user *) arg; | |
2d507a01 | 884 | int ret; |
3d6392cf | 885 | |
3d6392cf JA |
886 | switch (cmd) { |
887 | /* | |
888 | * our own ioctls | |
889 | */ | |
890 | case SG_GET_COMMAND_Q: | |
891 | return put_user(bd->max_queue, uarg); | |
5309cb38 | 892 | case SG_SET_COMMAND_Q: { |
3d6392cf JA |
893 | int queue; |
894 | ||
895 | if (get_user(queue, uarg)) | |
896 | return -EFAULT; | |
5309cb38 | 897 | if (queue < 1) |
3d6392cf JA |
898 | return -EINVAL; |
899 | ||
5309cb38 | 900 | spin_lock_irq(&bd->lock); |
3d6392cf | 901 | bd->max_queue = queue; |
5309cb38 | 902 | spin_unlock_irq(&bd->lock); |
3d6392cf JA |
903 | return 0; |
904 | } | |
905 | ||
906 | /* | |
907 | * SCSI/sg ioctls | |
908 | */ | |
909 | case SG_GET_VERSION_NUM: | |
910 | case SCSI_IOCTL_GET_IDLUN: | |
911 | case SCSI_IOCTL_GET_BUS_NUMBER: | |
912 | case SG_SET_TIMEOUT: | |
913 | case SG_GET_TIMEOUT: | |
914 | case SG_GET_RESERVED_SIZE: | |
915 | case SG_SET_RESERVED_SIZE: | |
916 | case SG_EMULATED_HOST: | |
3d6392cf JA |
917 | case SCSI_IOCTL_SEND_COMMAND: { |
918 | void __user *uarg = (void __user *) arg; | |
74f3c8af | 919 | return scsi_cmd_ioctl(bd->queue, NULL, file->f_mode, cmd, uarg); |
3d6392cf | 920 | } |
10e8855b FT |
921 | case SG_IO: { |
922 | struct request *rq; | |
2c9ecdf4 | 923 | struct bio *bio, *bidi_bio = NULL; |
10e8855b FT |
924 | struct sg_io_v4 hdr; |
925 | ||
926 | if (copy_from_user(&hdr, uarg, sizeof(hdr))) | |
927 | return -EFAULT; | |
928 | ||
abf54393 | 929 | rq = bsg_map_hdr(bd, &hdr, file->f_mode & FMODE_WRITE); |
10e8855b FT |
930 | if (IS_ERR(rq)) |
931 | return PTR_ERR(rq); | |
932 | ||
933 | bio = rq->bio; | |
2c9ecdf4 FT |
934 | if (rq->next_rq) |
935 | bidi_bio = rq->next_rq->bio; | |
d351af01 | 936 | blk_execute_rq(bd->queue, NULL, rq, 0); |
2d507a01 | 937 | ret = blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio); |
10e8855b FT |
938 | |
939 | if (copy_to_user(uarg, &hdr, sizeof(hdr))) | |
940 | return -EFAULT; | |
b711afa6 | 941 | |
2d507a01 | 942 | return ret; |
10e8855b | 943 | } |
3d6392cf JA |
944 | /* |
945 | * block device ioctls | |
946 | */ | |
947 | default: | |
948 | #if 0 | |
949 | return ioctl_by_bdev(bd->bdev, cmd, arg); | |
950 | #else | |
951 | return -ENOTTY; | |
952 | #endif | |
953 | } | |
954 | } | |
955 | ||
7344be05 | 956 | static const struct file_operations bsg_fops = { |
3d6392cf JA |
957 | .read = bsg_read, |
958 | .write = bsg_write, | |
959 | .poll = bsg_poll, | |
960 | .open = bsg_open, | |
961 | .release = bsg_release, | |
25fd1643 | 962 | .unlocked_ioctl = bsg_ioctl, |
3d6392cf JA |
963 | .owner = THIS_MODULE, |
964 | }; | |
965 | ||
d351af01 | 966 | void bsg_unregister_queue(struct request_queue *q) |
3d6392cf | 967 | { |
d351af01 | 968 | struct bsg_class_device *bcd = &q->bsg_dev; |
3d6392cf | 969 | |
df468820 FT |
970 | if (!bcd->class_dev) |
971 | return; | |
3d6392cf JA |
972 | |
973 | mutex_lock(&bsg_mutex); | |
598443a2 | 974 | idr_remove(&bsg_minor_idr, bcd->minor); |
d351af01 | 975 | sysfs_remove_link(&q->kobj, "bsg"); |
ee959b00 | 976 | device_unregister(bcd->class_dev); |
3d6392cf | 977 | bcd->class_dev = NULL; |
97f46ae4 | 978 | kref_put(&bcd->ref, bsg_kref_release_function); |
3d6392cf JA |
979 | mutex_unlock(&bsg_mutex); |
980 | } | |
4cf0723a | 981 | EXPORT_SYMBOL_GPL(bsg_unregister_queue); |
3d6392cf | 982 | |
97f46ae4 FT |
983 | int bsg_register_queue(struct request_queue *q, struct device *parent, |
984 | const char *name, void (*release)(struct device *)) | |
3d6392cf | 985 | { |
598443a2 | 986 | struct bsg_class_device *bcd; |
3d6392cf | 987 | dev_t dev; |
598443a2 | 988 | int ret, minor; |
ee959b00 | 989 | struct device *class_dev = NULL; |
39dca558 JB |
990 | const char *devname; |
991 | ||
992 | if (name) | |
993 | devname = name; | |
994 | else | |
3ada8b7e | 995 | devname = dev_name(parent); |
3d6392cf JA |
996 | |
997 | /* | |
998 | * we need a proper transport to send commands, not a stacked device | |
999 | */ | |
1000 | if (!q->request_fn) | |
1001 | return 0; | |
1002 | ||
d351af01 | 1003 | bcd = &q->bsg_dev; |
3d6392cf | 1004 | memset(bcd, 0, sizeof(*bcd)); |
3d6392cf JA |
1005 | |
1006 | mutex_lock(&bsg_mutex); | |
292b7f27 | 1007 | |
598443a2 FT |
1008 | ret = idr_pre_get(&bsg_minor_idr, GFP_KERNEL); |
1009 | if (!ret) { | |
1010 | ret = -ENOMEM; | |
1011 | goto unlock; | |
292b7f27 FT |
1012 | } |
1013 | ||
598443a2 FT |
1014 | ret = idr_get_new(&bsg_minor_idr, bcd, &minor); |
1015 | if (ret < 0) | |
1016 | goto unlock; | |
292b7f27 | 1017 | |
598443a2 FT |
1018 | if (minor >= BSG_MAX_DEVS) { |
1019 | printk(KERN_ERR "bsg: too many bsg devices\n"); | |
1020 | ret = -EINVAL; | |
1021 | goto remove_idr; | |
1022 | } | |
1023 | ||
1024 | bcd->minor = minor; | |
d351af01 | 1025 | bcd->queue = q; |
97f46ae4 FT |
1026 | bcd->parent = get_device(parent); |
1027 | bcd->release = release; | |
1028 | kref_init(&bcd->ref); | |
46f6ef4a | 1029 | dev = MKDEV(bsg_major, bcd->minor); |
1ff9f542 | 1030 | class_dev = device_create(bsg_class, parent, dev, NULL, "%s", devname); |
4e2872d6 FT |
1031 | if (IS_ERR(class_dev)) { |
1032 | ret = PTR_ERR(class_dev); | |
598443a2 | 1033 | goto put_dev; |
4e2872d6 FT |
1034 | } |
1035 | bcd->class_dev = class_dev; | |
1036 | ||
abce891a | 1037 | if (q->kobj.sd) { |
4e2872d6 FT |
1038 | ret = sysfs_create_link(&q->kobj, &bcd->class_dev->kobj, "bsg"); |
1039 | if (ret) | |
598443a2 | 1040 | goto unregister_class_dev; |
4e2872d6 FT |
1041 | } |
1042 | ||
3d6392cf JA |
1043 | mutex_unlock(&bsg_mutex); |
1044 | return 0; | |
6826ee4f | 1045 | |
598443a2 | 1046 | unregister_class_dev: |
ee959b00 | 1047 | device_unregister(class_dev); |
598443a2 | 1048 | put_dev: |
97f46ae4 | 1049 | put_device(parent); |
598443a2 FT |
1050 | remove_idr: |
1051 | idr_remove(&bsg_minor_idr, minor); | |
1052 | unlock: | |
264a0472 | 1053 | mutex_unlock(&bsg_mutex); |
4e2872d6 FT |
1054 | return ret; |
1055 | } | |
4cf0723a | 1056 | EXPORT_SYMBOL_GPL(bsg_register_queue); |
4e2872d6 | 1057 | |
7e7654a9 | 1058 | static struct cdev bsg_cdev; |
292b7f27 | 1059 | |
3d6392cf JA |
1060 | static int __init bsg_init(void) |
1061 | { | |
1062 | int ret, i; | |
46f6ef4a | 1063 | dev_t devid; |
3d6392cf | 1064 | |
5309cb38 | 1065 | bsg_cmd_cachep = kmem_cache_create("bsg_cmd", |
20c2df83 | 1066 | sizeof(struct bsg_command), 0, 0, NULL); |
5309cb38 JA |
1067 | if (!bsg_cmd_cachep) { |
1068 | printk(KERN_ERR "bsg: failed creating slab cache\n"); | |
1069 | return -ENOMEM; | |
1070 | } | |
1071 | ||
25fd1643 | 1072 | for (i = 0; i < BSG_LIST_ARRAY_SIZE; i++) |
3d6392cf JA |
1073 | INIT_HLIST_HEAD(&bsg_device_list[i]); |
1074 | ||
1075 | bsg_class = class_create(THIS_MODULE, "bsg"); | |
5309cb38 | 1076 | if (IS_ERR(bsg_class)) { |
9b9f770c FT |
1077 | ret = PTR_ERR(bsg_class); |
1078 | goto destroy_kmemcache; | |
5309cb38 | 1079 | } |
3d6392cf | 1080 | |
46f6ef4a | 1081 | ret = alloc_chrdev_region(&devid, 0, BSG_MAX_DEVS, "bsg"); |
9b9f770c FT |
1082 | if (ret) |
1083 | goto destroy_bsg_class; | |
292b7f27 | 1084 | |
46f6ef4a JA |
1085 | bsg_major = MAJOR(devid); |
1086 | ||
292b7f27 | 1087 | cdev_init(&bsg_cdev, &bsg_fops); |
46f6ef4a | 1088 | ret = cdev_add(&bsg_cdev, MKDEV(bsg_major, 0), BSG_MAX_DEVS); |
9b9f770c FT |
1089 | if (ret) |
1090 | goto unregister_chrdev; | |
3d6392cf | 1091 | |
5d3a8cd3 | 1092 | printk(KERN_INFO BSG_DESCRIPTION " version " BSG_VERSION |
0ed081ce | 1093 | " loaded (major %d)\n", bsg_major); |
3d6392cf | 1094 | return 0; |
9b9f770c FT |
1095 | unregister_chrdev: |
1096 | unregister_chrdev_region(MKDEV(bsg_major, 0), BSG_MAX_DEVS); | |
1097 | destroy_bsg_class: | |
1098 | class_destroy(bsg_class); | |
1099 | destroy_kmemcache: | |
1100 | kmem_cache_destroy(bsg_cmd_cachep); | |
1101 | return ret; | |
3d6392cf JA |
1102 | } |
1103 | ||
1104 | MODULE_AUTHOR("Jens Axboe"); | |
0ed081ce | 1105 | MODULE_DESCRIPTION(BSG_DESCRIPTION); |
3d6392cf JA |
1106 | MODULE_LICENSE("GPL"); |
1107 | ||
4e2872d6 | 1108 | device_initcall(bsg_init); |