blob: 302ac1f5af391b7058aad198615cdf1fee29931d [file] [log] [blame]
Jens Axboe3d6392c2007-07-09 12:38:05 +02001/*
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +09002 * bsg.c - block layer implementation of the sg v4 interface
Jens Axboe3d6392c2007-07-09 12:38:05 +02003 *
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 */
Jens Axboe3d6392c2007-07-09 12:38:05 +020012#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>
FUJITA Tomonori598443a2007-07-23 09:33:26 +090020#include <linux/idr.h>
Jens Axboe3d6392c2007-07-09 12:38:05 +020021#include <linux/bsg.h>
22
23#include <scsi/scsi.h>
24#include <scsi/scsi_ioctl.h>
25#include <scsi/scsi_cmnd.h>
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +020026#include <scsi/scsi_device.h>
27#include <scsi/scsi_driver.h>
Jens Axboe3d6392c2007-07-09 12:38:05 +020028#include <scsi/sg.h>
29
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +020030#define BSG_DESCRIPTION "Block layer SCSI generic (bsg) driver"
31#define BSG_VERSION "0.4"
Jens Axboe3d6392c2007-07-09 12:38:05 +020032
Jens Axboe3d6392c2007-07-09 12:38:05 +020033struct bsg_device {
Jens Axboe165125e2007-07-24 09:28:11 +020034 struct request_queue *queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +020035 spinlock_t lock;
36 struct list_head busy_list;
37 struct list_head done_list;
38 struct hlist_node dev_list;
39 atomic_t ref_count;
Jens Axboe3d6392c2007-07-09 12:38:05 +020040 int queued_cmds;
41 int done_cmds;
Jens Axboe3d6392c2007-07-09 12:38:05 +020042 wait_queue_head_t wq_done;
43 wait_queue_head_t wq_free;
FUJITA Tomonorid351af02007-07-09 12:40:35 +020044 char name[BUS_ID_SIZE];
Jens Axboe3d6392c2007-07-09 12:38:05 +020045 int max_queue;
46 unsigned long flags;
47};
48
49enum {
50 BSG_F_BLOCK = 1,
51 BSG_F_WRITE_PERM = 2,
52};
53
Jens Axboe5309cb32007-01-23 16:24:41 +010054#define BSG_DEFAULT_CMDS 64
FUJITA Tomonori292b7f22007-03-28 13:29:58 +020055#define BSG_MAX_DEVS 32768
Jens Axboe3d6392c2007-07-09 12:38:05 +020056
57#undef BSG_DEBUG
58
59#ifdef BSG_DEBUG
60#define dprintk(fmt, args...) printk(KERN_ERR "%s: " fmt, __FUNCTION__, ##args)
61#else
62#define dprintk(fmt, args...)
63#endif
64
Jens Axboe3d6392c2007-07-09 12:38:05 +020065static DEFINE_MUTEX(bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +090066static DEFINE_IDR(bsg_minor_idr);
Jens Axboe3d6392c2007-07-09 12:38:05 +020067
Jens Axboe25fd1642007-07-17 08:52:29 +020068#define BSG_LIST_ARRAY_SIZE 8
Jens Axboe25fd1642007-07-17 08:52:29 +020069static struct hlist_head bsg_device_list[BSG_LIST_ARRAY_SIZE];
Jens Axboe3d6392c2007-07-09 12:38:05 +020070
71static struct class *bsg_class;
Jens Axboe46f6ef42007-07-17 08:56:10 +020072static int bsg_major;
Jens Axboe3d6392c2007-07-09 12:38:05 +020073
Jens Axboe5309cb32007-01-23 16:24:41 +010074static struct kmem_cache *bsg_cmd_cachep;
75
Jens Axboe3d6392c2007-07-09 12:38:05 +020076/*
77 * our internal command type
78 */
79struct bsg_command {
80 struct bsg_device *bd;
81 struct list_head list;
82 struct request *rq;
83 struct bio *bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +020084 struct bio *bidi_bio;
Jens Axboe3d6392c2007-07-09 12:38:05 +020085 int err;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +010086 struct sg_io_v4 hdr;
Jens Axboe3d6392c2007-07-09 12:38:05 +020087 char sense[SCSI_SENSE_BUFFERSIZE];
88};
89
90static void bsg_free_command(struct bsg_command *bc)
91{
92 struct bsg_device *bd = bc->bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +020093 unsigned long flags;
94
Jens Axboe5309cb32007-01-23 16:24:41 +010095 kmem_cache_free(bsg_cmd_cachep, bc);
Jens Axboe3d6392c2007-07-09 12:38:05 +020096
97 spin_lock_irqsave(&bd->lock, flags);
98 bd->queued_cmds--;
Jens Axboe3d6392c2007-07-09 12:38:05 +020099 spin_unlock_irqrestore(&bd->lock, flags);
100
101 wake_up(&bd->wq_free);
102}
103
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200104static struct bsg_command *bsg_alloc_command(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200105{
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200106 struct bsg_command *bc = ERR_PTR(-EINVAL);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200107
108 spin_lock_irq(&bd->lock);
109
110 if (bd->queued_cmds >= bd->max_queue)
111 goto out;
112
Jens Axboe3d6392c2007-07-09 12:38:05 +0200113 bd->queued_cmds++;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200114 spin_unlock_irq(&bd->lock);
115
Jens Axboe25fd1642007-07-17 08:52:29 +0200116 bc = kmem_cache_zalloc(bsg_cmd_cachep, GFP_KERNEL);
Jens Axboe5309cb32007-01-23 16:24:41 +0100117 if (unlikely(!bc)) {
118 spin_lock_irq(&bd->lock);
FUJITA Tomonori7e75d732007-01-24 09:05:54 +0100119 bd->queued_cmds--;
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200120 bc = ERR_PTR(-ENOMEM);
FUJITA Tomonori7e75d732007-01-24 09:05:54 +0100121 goto out;
Jens Axboe5309cb32007-01-23 16:24:41 +0100122 }
123
Jens Axboe3d6392c2007-07-09 12:38:05 +0200124 bc->bd = bd;
125 INIT_LIST_HEAD(&bc->list);
Jens Axboe5309cb32007-01-23 16:24:41 +0100126 dprintk("%s: returning free cmd %p\n", bd->name, bc);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200127 return bc;
128out:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200129 spin_unlock_irq(&bd->lock);
130 return bc;
131}
132
FUJITA Tomonori1c1133e2007-07-17 12:21:15 +0200133static inline struct hlist_head *bsg_dev_idx_hash(int index)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200134{
FUJITA Tomonori1c1133e2007-07-17 12:21:15 +0200135 return &bsg_device_list[index & (BSG_LIST_ARRAY_SIZE - 1)];
Jens Axboe3d6392c2007-07-09 12:38:05 +0200136}
137
Jens Axboe25fd1642007-07-17 08:52:29 +0200138static int bsg_io_schedule(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200139{
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
Jens Axboe25fd1642007-07-17 08:52:29 +0200163 prepare_to_wait(&bd->wq_done, &wait, TASK_UNINTERRUPTIBLE);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200164 spin_unlock_irq(&bd->lock);
165 io_schedule();
166 finish_wait(&bd->wq_done, &wait);
167
Jens Axboe3d6392c2007-07-09 12:38:05 +0200168 return ret;
169unlock:
170 spin_unlock_irq(&bd->lock);
171 return ret;
172}
173
Jens Axboe165125e2007-07-24 09:28:11 +0200174static int blk_fill_sgv4_hdr_rq(struct request_queue *q, struct request *rq,
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100175 struct sg_io_v4 *hdr, int has_write_perm)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200176{
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100177 memset(rq->cmd, 0, BLK_MAX_CDB); /* ATAPI hates garbage after CDB */
178
179 if (copy_from_user(rq->cmd, (void *)(unsigned long)hdr->request,
180 hdr->request_len))
181 return -EFAULT;
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200182
183 if (hdr->subprotocol == BSG_SUB_PROTOCOL_SCSI_CMD) {
184 if (blk_verify_command(rq->cmd, has_write_perm))
185 return -EPERM;
186 } else if (!capable(CAP_SYS_RAWIO))
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100187 return -EPERM;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200188
189 /*
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100190 * fill in request structure
Jens Axboe3d6392c2007-07-09 12:38:05 +0200191 */
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100192 rq->cmd_len = hdr->request_len;
193 rq->cmd_type = REQ_TYPE_BLOCK_PC;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200194
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100195 rq->timeout = (hdr->timeout * HZ) / 1000;
196 if (!rq->timeout)
197 rq->timeout = q->sg_timeout;
198 if (!rq->timeout)
199 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200200
201 return 0;
202}
203
204/*
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100205 * Check if sg_io_v4 from user is allowed and valid
206 */
207static int
Jens Axboe165125e2007-07-24 09:28:11 +0200208bsg_validate_sgv4_hdr(struct request_queue *q, struct sg_io_v4 *hdr, int *rw)
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100209{
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200210 int ret = 0;
211
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100212 if (hdr->guard != 'Q')
213 return -EINVAL;
214 if (hdr->request_len > BLK_MAX_CDB)
215 return -EINVAL;
216 if (hdr->dout_xfer_len > (q->max_sectors << 9) ||
217 hdr->din_xfer_len > (q->max_sectors << 9))
218 return -EIO;
219
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200220 switch (hdr->protocol) {
221 case BSG_PROTOCOL_SCSI:
222 switch (hdr->subprotocol) {
223 case BSG_SUB_PROTOCOL_SCSI_CMD:
224 case BSG_SUB_PROTOCOL_SCSI_TRANSPORT:
225 break;
226 default:
227 ret = -EINVAL;
228 }
229 break;
230 default:
231 ret = -EINVAL;
232 }
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100233
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100234 *rw = hdr->dout_xfer_len ? WRITE : READ;
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200235 return ret;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100236}
237
238/*
239 * map sg_io_v4 to a request.
Jens Axboe3d6392c2007-07-09 12:38:05 +0200240 */
241static struct request *
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100242bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200243{
Jens Axboe165125e2007-07-24 09:28:11 +0200244 struct request_queue *q = bd->queue;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200245 struct request *rq, *next_rq = NULL;
Jens Axboe25fd1642007-07-17 08:52:29 +0200246 int ret, rw;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100247 unsigned int dxfer_len;
248 void *dxferp = NULL;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200249
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100250 dprintk("map hdr %llx/%u %llx/%u\n", (unsigned long long) hdr->dout_xferp,
251 hdr->dout_xfer_len, (unsigned long long) hdr->din_xferp,
252 hdr->din_xfer_len);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200253
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100254 ret = bsg_validate_sgv4_hdr(q, hdr, &rw);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200255 if (ret)
256 return ERR_PTR(ret);
257
258 /*
259 * map scatter-gather elements seperately and string them to request
260 */
261 rq = blk_get_request(q, rw, GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200262 if (!rq)
263 return ERR_PTR(-ENOMEM);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100264 ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, test_bit(BSG_F_WRITE_PERM,
265 &bd->flags));
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200266 if (ret)
267 goto out;
268
269 if (rw == WRITE && hdr->din_xfer_len) {
270 if (!test_bit(QUEUE_FLAG_BIDI, &q->queue_flags)) {
271 ret = -EOPNOTSUPP;
272 goto out;
273 }
274
275 next_rq = blk_get_request(q, READ, GFP_KERNEL);
276 if (!next_rq) {
277 ret = -ENOMEM;
278 goto out;
279 }
280 rq->next_rq = next_rq;
James Bottomley40f62022008-01-25 20:05:55 -0600281 next_rq->cmd_type = rq->cmd_type;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200282
283 dxferp = (void*)(unsigned long)hdr->din_xferp;
284 ret = blk_rq_map_user(q, next_rq, dxferp, hdr->din_xfer_len);
285 if (ret)
286 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200287 }
288
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100289 if (hdr->dout_xfer_len) {
290 dxfer_len = hdr->dout_xfer_len;
291 dxferp = (void*)(unsigned long)hdr->dout_xferp;
292 } else if (hdr->din_xfer_len) {
293 dxfer_len = hdr->din_xfer_len;
294 dxferp = (void*)(unsigned long)hdr->din_xferp;
295 } else
296 dxfer_len = 0;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200297
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100298 if (dxfer_len) {
299 ret = blk_rq_map_user(q, rq, dxferp, dxfer_len);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200300 if (ret)
301 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200302 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200303 return rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200304out:
305 blk_put_request(rq);
306 if (next_rq) {
307 blk_rq_unmap_user(next_rq->bio);
308 blk_put_request(next_rq);
309 }
310 return ERR_PTR(ret);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200311}
312
313/*
314 * async completion call-back from the block layer, when scsi/ide/whatever
315 * calls end_that_request_last() on a request
316 */
317static void bsg_rq_end_io(struct request *rq, int uptodate)
318{
319 struct bsg_command *bc = rq->end_io_data;
320 struct bsg_device *bd = bc->bd;
321 unsigned long flags;
322
Jens Axboe5309cb32007-01-23 16:24:41 +0100323 dprintk("%s: finished rq %p bc %p, bio %p stat %d\n",
324 bd->name, rq, bc, bc->bio, uptodate);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200325
326 bc->hdr.duration = jiffies_to_msecs(jiffies - bc->hdr.duration);
327
328 spin_lock_irqsave(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200329 list_move_tail(&bc->list, &bd->done_list);
330 bd->done_cmds++;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200331 spin_unlock_irqrestore(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200332
333 wake_up(&bd->wq_done);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200334}
335
336/*
337 * do final setup of a 'bc' and submit the matching 'rq' to the block
338 * layer for io
339 */
Jens Axboe165125e2007-07-24 09:28:11 +0200340static void bsg_add_command(struct bsg_device *bd, struct request_queue *q,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200341 struct bsg_command *bc, struct request *rq)
342{
343 rq->sense = bc->sense;
344 rq->sense_len = 0;
345
346 /*
347 * add bc command to busy queue and submit rq for io
348 */
349 bc->rq = rq;
350 bc->bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200351 if (rq->next_rq)
352 bc->bidi_bio = rq->next_rq->bio;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200353 bc->hdr.duration = jiffies;
354 spin_lock_irq(&bd->lock);
355 list_add_tail(&bc->list, &bd->busy_list);
356 spin_unlock_irq(&bd->lock);
357
358 dprintk("%s: queueing rq %p, bc %p\n", bd->name, rq, bc);
359
360 rq->end_io_data = bc;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200361 blk_execute_rq_nowait(q, NULL, rq, 1, bsg_rq_end_io);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200362}
363
Jens Axboe25fd1642007-07-17 08:52:29 +0200364static struct bsg_command *bsg_next_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200365{
366 struct bsg_command *bc = NULL;
367
368 spin_lock_irq(&bd->lock);
369 if (bd->done_cmds) {
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900370 bc = list_first_entry(&bd->done_list, struct bsg_command, list);
Jens Axboe25fd1642007-07-17 08:52:29 +0200371 list_del(&bc->list);
372 bd->done_cmds--;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200373 }
374 spin_unlock_irq(&bd->lock);
375
376 return bc;
377}
378
379/*
380 * Get a finished command from the done list
381 */
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200382static struct bsg_command *bsg_get_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200383{
384 struct bsg_command *bc;
385 int ret;
386
387 do {
388 bc = bsg_next_done_cmd(bd);
389 if (bc)
390 break;
391
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200392 if (!test_bit(BSG_F_BLOCK, &bd->flags)) {
393 bc = ERR_PTR(-EAGAIN);
394 break;
395 }
396
397 ret = wait_event_interruptible(bd->wq_done, bd->done_cmds);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200398 if (ret) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200399 bc = ERR_PTR(-ERESTARTSYS);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200400 break;
401 }
402 } while (1);
403
404 dprintk("%s: returning done %p\n", bd->name, bc);
405
406 return bc;
407}
408
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100409static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr,
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200410 struct bio *bio, struct bio *bidi_bio)
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100411{
412 int ret = 0;
413
414 dprintk("rq %p bio %p %u\n", rq, bio, rq->errors);
415 /*
416 * fill in all the output members
417 */
418 hdr->device_status = status_byte(rq->errors);
419 hdr->transport_status = host_byte(rq->errors);
420 hdr->driver_status = driver_byte(rq->errors);
421 hdr->info = 0;
422 if (hdr->device_status || hdr->transport_status || hdr->driver_status)
423 hdr->info |= SG_INFO_CHECK;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100424 hdr->response_len = 0;
425
426 if (rq->sense_len && hdr->response) {
Jens Axboe25fd1642007-07-17 08:52:29 +0200427 int len = min_t(unsigned int, hdr->max_response_len,
428 rq->sense_len);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100429
430 ret = copy_to_user((void*)(unsigned long)hdr->response,
431 rq->sense, len);
432 if (!ret)
433 hdr->response_len = len;
434 else
435 ret = -EFAULT;
436 }
437
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200438 if (rq->next_rq) {
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100439 hdr->dout_resid = rq->data_len;
440 hdr->din_resid = rq->next_rq->data_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200441 blk_rq_unmap_user(bidi_bio);
442 blk_put_request(rq->next_rq);
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900443 } else if (rq_data_dir(rq) == READ)
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100444 hdr->din_resid = rq->data_len;
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900445 else
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100446 hdr->dout_resid = rq->data_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200447
James Bottomley2d507a02007-12-29 10:59:53 -0600448 /*
449 * If the request generated a negative error number, return it
450 * (providing we aren't already returning an error); if it's
451 * just a protocol response (i.e. non negative), that gets
452 * processed above.
453 */
454 if (!ret && rq->errors < 0)
455 ret = rq->errors;
456
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100457 blk_rq_unmap_user(bio);
458 blk_put_request(rq);
459
460 return ret;
461}
462
Jens Axboe3d6392c2007-07-09 12:38:05 +0200463static int bsg_complete_all_commands(struct bsg_device *bd)
464{
465 struct bsg_command *bc;
466 int ret, tret;
467
468 dprintk("%s: entered\n", bd->name);
469
Jens Axboe3d6392c2007-07-09 12:38:05 +0200470 /*
471 * wait for all commands to complete
472 */
473 ret = 0;
474 do {
Jens Axboe25fd1642007-07-17 08:52:29 +0200475 ret = bsg_io_schedule(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200476 /*
477 * look for -ENODATA specifically -- we'll sometimes get
478 * -ERESTARTSYS when we've taken a signal, but we can't
479 * return until we're done freeing the queue, so ignore
480 * it. The signal will get handled when we're done freeing
481 * the bsg_device.
482 */
483 } while (ret != -ENODATA);
484
485 /*
486 * discard done commands
487 */
488 ret = 0;
489 do {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200490 spin_lock_irq(&bd->lock);
491 if (!bd->queued_cmds) {
492 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200493 break;
494 }
FUJITA Tomonoriefba1a32007-06-07 13:24:06 +0200495 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200496
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200497 bc = bsg_get_done_cmd(bd);
498 if (IS_ERR(bc))
499 break;
500
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200501 tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
502 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200503 if (!ret)
504 ret = tret;
505
506 bsg_free_command(bc);
507 } while (1);
508
509 return ret;
510}
511
Jens Axboe25fd1642007-07-17 08:52:29 +0200512static int
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200513__bsg_read(char __user *buf, size_t count, struct bsg_device *bd,
514 const struct iovec *iov, ssize_t *bytes_read)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200515{
516 struct bsg_command *bc;
517 int nr_commands, ret;
518
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100519 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200520 return -EINVAL;
521
522 ret = 0;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100523 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200524 while (nr_commands) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200525 bc = bsg_get_done_cmd(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200526 if (IS_ERR(bc)) {
527 ret = PTR_ERR(bc);
528 break;
529 }
530
531 /*
532 * this is the only case where we need to copy data back
533 * after completing the request. so do that here,
534 * bsg_complete_work() cannot do that for us
535 */
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200536 ret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
537 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200538
Jens Axboe25fd1642007-07-17 08:52:29 +0200539 if (copy_to_user(buf, &bc->hdr, sizeof(bc->hdr)))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200540 ret = -EFAULT;
541
542 bsg_free_command(bc);
543
544 if (ret)
545 break;
546
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100547 buf += sizeof(struct sg_io_v4);
548 *bytes_read += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200549 nr_commands--;
550 }
551
552 return ret;
553}
554
555static inline void bsg_set_block(struct bsg_device *bd, struct file *file)
556{
557 if (file->f_flags & O_NONBLOCK)
558 clear_bit(BSG_F_BLOCK, &bd->flags);
559 else
560 set_bit(BSG_F_BLOCK, &bd->flags);
561}
562
563static inline void bsg_set_write_perm(struct bsg_device *bd, struct file *file)
564{
565 if (file->f_mode & FMODE_WRITE)
566 set_bit(BSG_F_WRITE_PERM, &bd->flags);
567 else
568 clear_bit(BSG_F_WRITE_PERM, &bd->flags);
569}
570
Jens Axboe25fd1642007-07-17 08:52:29 +0200571/*
572 * Check if the error is a "real" error that we should return.
573 */
Jens Axboe3d6392c2007-07-09 12:38:05 +0200574static inline int err_block_err(int ret)
575{
576 if (ret && ret != -ENOSPC && ret != -ENODATA && ret != -EAGAIN)
577 return 1;
578
579 return 0;
580}
581
582static ssize_t
583bsg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
584{
585 struct bsg_device *bd = file->private_data;
586 int ret;
587 ssize_t bytes_read;
588
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100589 dprintk("%s: read %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200590
591 bsg_set_block(bd, file);
592 bytes_read = 0;
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200593 ret = __bsg_read(buf, count, bd, NULL, &bytes_read);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200594 *ppos = bytes_read;
595
596 if (!bytes_read || (bytes_read && err_block_err(ret)))
597 bytes_read = ret;
598
599 return bytes_read;
600}
601
Jens Axboe25fd1642007-07-17 08:52:29 +0200602static int __bsg_write(struct bsg_device *bd, const char __user *buf,
603 size_t count, ssize_t *bytes_written)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200604{
605 struct bsg_command *bc;
606 struct request *rq;
607 int ret, nr_commands;
608
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100609 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200610 return -EINVAL;
611
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100612 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200613 rq = NULL;
614 bc = NULL;
615 ret = 0;
616 while (nr_commands) {
Jens Axboe165125e2007-07-24 09:28:11 +0200617 struct request_queue *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200618
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200619 bc = bsg_alloc_command(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200620 if (IS_ERR(bc)) {
621 ret = PTR_ERR(bc);
622 bc = NULL;
623 break;
624 }
625
Jens Axboe3d6392c2007-07-09 12:38:05 +0200626 if (copy_from_user(&bc->hdr, buf, sizeof(bc->hdr))) {
627 ret = -EFAULT;
628 break;
629 }
630
631 /*
632 * get a request, fill in the blanks, and add to request queue
633 */
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100634 rq = bsg_map_hdr(bd, &bc->hdr);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200635 if (IS_ERR(rq)) {
636 ret = PTR_ERR(rq);
637 rq = NULL;
638 break;
639 }
640
641 bsg_add_command(bd, q, bc, rq);
642 bc = NULL;
643 rq = NULL;
644 nr_commands--;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100645 buf += sizeof(struct sg_io_v4);
Jens Axboe25fd1642007-07-17 08:52:29 +0200646 *bytes_written += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200647 }
648
Jens Axboe3d6392c2007-07-09 12:38:05 +0200649 if (bc)
650 bsg_free_command(bc);
651
652 return ret;
653}
654
655static ssize_t
656bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
657{
658 struct bsg_device *bd = file->private_data;
Jens Axboe25fd1642007-07-17 08:52:29 +0200659 ssize_t bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200660 int ret;
661
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100662 dprintk("%s: write %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200663
664 bsg_set_block(bd, file);
665 bsg_set_write_perm(bd, file);
666
Jens Axboe25fd1642007-07-17 08:52:29 +0200667 bytes_written = 0;
668 ret = __bsg_write(bd, buf, count, &bytes_written);
669 *ppos = bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200670
671 /*
672 * return bytes written on non-fatal errors
673 */
Jens Axboe25fd1642007-07-17 08:52:29 +0200674 if (!bytes_written || (bytes_written && err_block_err(ret)))
675 bytes_written = ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200676
Jens Axboe25fd1642007-07-17 08:52:29 +0200677 dprintk("%s: returning %Zd\n", bd->name, bytes_written);
678 return bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200679}
680
Jens Axboe3d6392c2007-07-09 12:38:05 +0200681static struct bsg_device *bsg_alloc_device(void)
682{
Jens Axboe3d6392c2007-07-09 12:38:05 +0200683 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200684
685 bd = kzalloc(sizeof(struct bsg_device), GFP_KERNEL);
686 if (unlikely(!bd))
687 return NULL;
688
689 spin_lock_init(&bd->lock);
690
Jens Axboe5309cb32007-01-23 16:24:41 +0100691 bd->max_queue = BSG_DEFAULT_CMDS;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200692
693 INIT_LIST_HEAD(&bd->busy_list);
694 INIT_LIST_HEAD(&bd->done_list);
695 INIT_HLIST_NODE(&bd->dev_list);
696
697 init_waitqueue_head(&bd->wq_free);
698 init_waitqueue_head(&bd->wq_done);
699 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200700}
701
702static int bsg_put_device(struct bsg_device *bd)
703{
704 int ret = 0;
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900705 struct device *dev = bd->queue->bsg_dev.dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200706
707 mutex_lock(&bsg_mutex);
708
709 if (!atomic_dec_and_test(&bd->ref_count))
710 goto out;
711
712 dprintk("%s: tearing down\n", bd->name);
713
714 /*
715 * close can always block
716 */
717 set_bit(BSG_F_BLOCK, &bd->flags);
718
719 /*
720 * correct error detection baddies here again. it's the responsibility
721 * of the app to properly reap commands before close() if it wants
722 * fool-proof error detection
723 */
724 ret = bsg_complete_all_commands(bd);
725
726 blk_put_queue(bd->queue);
727 hlist_del(&bd->dev_list);
Jens Axboe5309cb32007-01-23 16:24:41 +0100728 kfree(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200729out:
730 mutex_unlock(&bsg_mutex);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900731 put_device(dev);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200732 return ret;
733}
734
735static struct bsg_device *bsg_add_device(struct inode *inode,
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200736 struct request_queue *rq,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200737 struct file *file)
738{
Jens Axboe25fd1642007-07-17 08:52:29 +0200739 struct bsg_device *bd;
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900740 int ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200741#ifdef BSG_DEBUG
742 unsigned char buf[32];
743#endif
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900744 ret = blk_get_queue(rq);
745 if (ret)
746 return ERR_PTR(-ENXIO);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200747
748 bd = bsg_alloc_device();
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900749 if (!bd) {
750 blk_put_queue(rq);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200751 return ERR_PTR(-ENOMEM);
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900752 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200753
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200754 bd->queue = rq;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200755 bsg_set_block(bd, file);
756
757 atomic_set(&bd->ref_count, 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200758 mutex_lock(&bsg_mutex);
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900759 hlist_add_head(&bd->dev_list, bsg_dev_idx_hash(iminor(inode)));
Jens Axboe3d6392c2007-07-09 12:38:05 +0200760
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200761 strncpy(bd->name, rq->bsg_dev.class_dev->class_id, sizeof(bd->name) - 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200762 dprintk("bound to <%s>, max queue %d\n",
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100763 format_dev_t(buf, inode->i_rdev), bd->max_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200764
765 mutex_unlock(&bsg_mutex);
766 return bd;
767}
768
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900769static struct bsg_device *__bsg_get_device(int minor, struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200770{
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900771 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200772 struct hlist_node *entry;
773
774 mutex_lock(&bsg_mutex);
775
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900776 hlist_for_each_entry(bd, entry, bsg_dev_idx_hash(minor), dev_list) {
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900777 if (bd->queue == q) {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200778 atomic_inc(&bd->ref_count);
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900779 goto found;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200780 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200781 }
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900782 bd = NULL;
783found:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200784 mutex_unlock(&bsg_mutex);
785 return bd;
786}
787
788static struct bsg_device *bsg_get_device(struct inode *inode, struct file *file)
789{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900790 struct bsg_device *bd;
791 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200792
Jens Axboe3d6392c2007-07-09 12:38:05 +0200793 /*
794 * find the class device
795 */
Jens Axboe3d6392c2007-07-09 12:38:05 +0200796 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900797 bcd = idr_find(&bsg_minor_idr, iminor(inode));
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900798 if (bcd)
799 get_device(bcd->dev);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200800 mutex_unlock(&bsg_mutex);
801
802 if (!bcd)
803 return ERR_PTR(-ENODEV);
804
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900805 bd = __bsg_get_device(iminor(inode), bcd->queue);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900806 if (bd)
807 return bd;
808
809 bd = bsg_add_device(inode, bcd->queue, file);
810 if (IS_ERR(bd))
811 put_device(bcd->dev);
812
813 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200814}
815
816static int bsg_open(struct inode *inode, struct file *file)
817{
818 struct bsg_device *bd = bsg_get_device(inode, file);
819
820 if (IS_ERR(bd))
821 return PTR_ERR(bd);
822
823 file->private_data = bd;
824 return 0;
825}
826
827static int bsg_release(struct inode *inode, struct file *file)
828{
829 struct bsg_device *bd = file->private_data;
830
831 file->private_data = NULL;
832 return bsg_put_device(bd);
833}
834
835static unsigned int bsg_poll(struct file *file, poll_table *wait)
836{
837 struct bsg_device *bd = file->private_data;
838 unsigned int mask = 0;
839
840 poll_wait(file, &bd->wq_done, wait);
841 poll_wait(file, &bd->wq_free, wait);
842
843 spin_lock_irq(&bd->lock);
844 if (!list_empty(&bd->done_list))
845 mask |= POLLIN | POLLRDNORM;
846 if (bd->queued_cmds >= bd->max_queue)
847 mask |= POLLOUT;
848 spin_unlock_irq(&bd->lock);
849
850 return mask;
851}
852
Jens Axboe25fd1642007-07-17 08:52:29 +0200853static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200854{
855 struct bsg_device *bd = file->private_data;
856 int __user *uarg = (int __user *) arg;
James Bottomley2d507a02007-12-29 10:59:53 -0600857 int ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200858
Jens Axboe3d6392c2007-07-09 12:38:05 +0200859 switch (cmd) {
860 /*
861 * our own ioctls
862 */
863 case SG_GET_COMMAND_Q:
864 return put_user(bd->max_queue, uarg);
Jens Axboe5309cb32007-01-23 16:24:41 +0100865 case SG_SET_COMMAND_Q: {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200866 int queue;
867
868 if (get_user(queue, uarg))
869 return -EFAULT;
Jens Axboe5309cb32007-01-23 16:24:41 +0100870 if (queue < 1)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200871 return -EINVAL;
872
Jens Axboe5309cb32007-01-23 16:24:41 +0100873 spin_lock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200874 bd->max_queue = queue;
Jens Axboe5309cb32007-01-23 16:24:41 +0100875 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200876 return 0;
877 }
878
879 /*
880 * SCSI/sg ioctls
881 */
882 case SG_GET_VERSION_NUM:
883 case SCSI_IOCTL_GET_IDLUN:
884 case SCSI_IOCTL_GET_BUS_NUMBER:
885 case SG_SET_TIMEOUT:
886 case SG_GET_TIMEOUT:
887 case SG_GET_RESERVED_SIZE:
888 case SG_SET_RESERVED_SIZE:
889 case SG_EMULATED_HOST:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200890 case SCSI_IOCTL_SEND_COMMAND: {
891 void __user *uarg = (void __user *) arg;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200892 return scsi_cmd_ioctl(file, bd->queue, NULL, cmd, uarg);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200893 }
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100894 case SG_IO: {
895 struct request *rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200896 struct bio *bio, *bidi_bio = NULL;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100897 struct sg_io_v4 hdr;
898
899 if (copy_from_user(&hdr, uarg, sizeof(hdr)))
900 return -EFAULT;
901
902 rq = bsg_map_hdr(bd, &hdr);
903 if (IS_ERR(rq))
904 return PTR_ERR(rq);
905
906 bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200907 if (rq->next_rq)
908 bidi_bio = rq->next_rq->bio;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200909 blk_execute_rq(bd->queue, NULL, rq, 0);
James Bottomley2d507a02007-12-29 10:59:53 -0600910 ret = blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100911
912 if (copy_to_user(uarg, &hdr, sizeof(hdr)))
913 return -EFAULT;
Jens Axboeb711afa2006-12-20 11:25:23 +0100914
James Bottomley2d507a02007-12-29 10:59:53 -0600915 return ret;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100916 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200917 /*
918 * block device ioctls
919 */
920 default:
921#if 0
922 return ioctl_by_bdev(bd->bdev, cmd, arg);
923#else
924 return -ENOTTY;
925#endif
926 }
927}
928
Arjan van de Ven7344be02007-10-15 11:01:53 +0200929static const struct file_operations bsg_fops = {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200930 .read = bsg_read,
931 .write = bsg_write,
932 .poll = bsg_poll,
933 .open = bsg_open,
934 .release = bsg_release,
Jens Axboe25fd1642007-07-17 08:52:29 +0200935 .unlocked_ioctl = bsg_ioctl,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200936 .owner = THIS_MODULE,
937};
938
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200939void bsg_unregister_queue(struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200940{
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200941 struct bsg_class_device *bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200942
FUJITA Tomonoridf468822007-07-21 13:23:25 +0900943 if (!bcd->class_dev)
944 return;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200945
946 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900947 idr_remove(&bsg_minor_idr, bcd->minor);
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200948 sysfs_remove_link(&q->kobj, "bsg");
James Bottomley39dca552007-07-20 18:22:17 -0500949 class_device_unregister(bcd->class_dev);
950 put_device(bcd->dev);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200951 bcd->class_dev = NULL;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200952 mutex_unlock(&bsg_mutex);
953}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +0200954EXPORT_SYMBOL_GPL(bsg_unregister_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200955
James Bottomley39dca552007-07-20 18:22:17 -0500956int bsg_register_queue(struct request_queue *q, struct device *gdev,
957 const char *name)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200958{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900959 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200960 dev_t dev;
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900961 int ret, minor;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +0200962 struct class_device *class_dev = NULL;
James Bottomley39dca552007-07-20 18:22:17 -0500963 const char *devname;
964
965 if (name)
966 devname = name;
967 else
968 devname = gdev->bus_id;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200969
970 /*
971 * we need a proper transport to send commands, not a stacked device
972 */
973 if (!q->request_fn)
974 return 0;
975
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200976 bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200977 memset(bcd, 0, sizeof(*bcd));
Jens Axboe3d6392c2007-07-09 12:38:05 +0200978
979 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900980
981 ret = idr_pre_get(&bsg_minor_idr, GFP_KERNEL);
982 if (!ret) {
983 ret = -ENOMEM;
984 goto unlock;
985 }
986
987 ret = idr_get_new(&bsg_minor_idr, bcd, &minor);
988 if (ret < 0)
989 goto unlock;
990
991 if (minor >= BSG_MAX_DEVS) {
FUJITA Tomonori292b7f22007-03-28 13:29:58 +0200992 printk(KERN_ERR "bsg: too many bsg devices\n");
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900993 ret = -EINVAL;
994 goto remove_idr;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +0200995 }
996
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900997 bcd->minor = minor;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200998 bcd->queue = q;
James Bottomley39dca552007-07-20 18:22:17 -0500999 bcd->dev = get_device(gdev);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001000 dev = MKDEV(bsg_major, bcd->minor);
James Bottomley39dca552007-07-20 18:22:17 -05001001 class_dev = class_device_create(bsg_class, NULL, dev, gdev, "%s",
1002 devname);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001003 if (IS_ERR(class_dev)) {
1004 ret = PTR_ERR(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001005 goto put_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001006 }
1007 bcd->class_dev = class_dev;
1008
Linus Torvaldsabce8912007-07-16 11:18:23 -07001009 if (q->kobj.sd) {
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001010 ret = sysfs_create_link(&q->kobj, &bcd->class_dev->kobj, "bsg");
1011 if (ret)
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001012 goto unregister_class_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001013 }
1014
Jens Axboe3d6392c2007-07-09 12:38:05 +02001015 mutex_unlock(&bsg_mutex);
1016 return 0;
James Bottomley6826ee42007-07-20 16:50:10 -05001017
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001018unregister_class_dev:
James Bottomley6826ee42007-07-20 16:50:10 -05001019 class_device_unregister(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001020put_dev:
James Bottomley39dca552007-07-20 18:22:17 -05001021 put_device(gdev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001022remove_idr:
1023 idr_remove(&bsg_minor_idr, minor);
1024unlock:
Jens Axboe264a0472007-01-23 16:30:17 +01001025 mutex_unlock(&bsg_mutex);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001026 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001027}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +02001028EXPORT_SYMBOL_GPL(bsg_register_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001029
Greg Kroah-Hartman7e7654a2007-09-12 15:06:57 -07001030static struct cdev bsg_cdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001031
Jens Axboe3d6392c2007-07-09 12:38:05 +02001032static int __init bsg_init(void)
1033{
1034 int ret, i;
Jens Axboe46f6ef42007-07-17 08:56:10 +02001035 dev_t devid;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001036
Jens Axboe5309cb32007-01-23 16:24:41 +01001037 bsg_cmd_cachep = kmem_cache_create("bsg_cmd",
Paul Mundt20c2df82007-07-20 10:11:58 +09001038 sizeof(struct bsg_command), 0, 0, NULL);
Jens Axboe5309cb32007-01-23 16:24:41 +01001039 if (!bsg_cmd_cachep) {
1040 printk(KERN_ERR "bsg: failed creating slab cache\n");
1041 return -ENOMEM;
1042 }
1043
Jens Axboe25fd1642007-07-17 08:52:29 +02001044 for (i = 0; i < BSG_LIST_ARRAY_SIZE; i++)
Jens Axboe3d6392c2007-07-09 12:38:05 +02001045 INIT_HLIST_HEAD(&bsg_device_list[i]);
1046
1047 bsg_class = class_create(THIS_MODULE, "bsg");
Jens Axboe5309cb32007-01-23 16:24:41 +01001048 if (IS_ERR(bsg_class)) {
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001049 ret = PTR_ERR(bsg_class);
1050 goto destroy_kmemcache;
Jens Axboe5309cb32007-01-23 16:24:41 +01001051 }
Jens Axboe3d6392c2007-07-09 12:38:05 +02001052
Jens Axboe46f6ef42007-07-17 08:56:10 +02001053 ret = alloc_chrdev_region(&devid, 0, BSG_MAX_DEVS, "bsg");
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001054 if (ret)
1055 goto destroy_bsg_class;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001056
Jens Axboe46f6ef42007-07-17 08:56:10 +02001057 bsg_major = MAJOR(devid);
1058
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001059 cdev_init(&bsg_cdev, &bsg_fops);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001060 ret = cdev_add(&bsg_cdev, MKDEV(bsg_major, 0), BSG_MAX_DEVS);
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001061 if (ret)
1062 goto unregister_chrdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001063
Jens Axboe5d3a8cd2007-07-17 15:10:09 +02001064 printk(KERN_INFO BSG_DESCRIPTION " version " BSG_VERSION
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001065 " loaded (major %d)\n", bsg_major);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001066 return 0;
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001067unregister_chrdev:
1068 unregister_chrdev_region(MKDEV(bsg_major, 0), BSG_MAX_DEVS);
1069destroy_bsg_class:
1070 class_destroy(bsg_class);
1071destroy_kmemcache:
1072 kmem_cache_destroy(bsg_cmd_cachep);
1073 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001074}
1075
1076MODULE_AUTHOR("Jens Axboe");
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001077MODULE_DESCRIPTION(BSG_DESCRIPTION);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001078MODULE_LICENSE("GPL");
1079
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001080device_initcall(bsg_init);