blob: 034112bfe1f32a3876449533530edc0ed875e677 [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>
Jonathan Corbet75bd2ef2008-05-15 09:09:23 -060022#include <linux/smp_lock.h>
Jens Axboe3d6392c2007-07-09 12:38:05 +020023
24#include <scsi/scsi.h>
25#include <scsi/scsi_ioctl.h>
26#include <scsi/scsi_cmnd.h>
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +020027#include <scsi/scsi_device.h>
28#include <scsi/scsi_driver.h>
Jens Axboe3d6392c2007-07-09 12:38:05 +020029#include <scsi/sg.h>
30
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +020031#define BSG_DESCRIPTION "Block layer SCSI generic (bsg) driver"
32#define BSG_VERSION "0.4"
Jens Axboe3d6392c2007-07-09 12:38:05 +020033
Jens Axboe3d6392c2007-07-09 12:38:05 +020034struct bsg_device {
Jens Axboe165125e2007-07-24 09:28:11 +020035 struct request_queue *queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +020036 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;
Jens Axboe3d6392c2007-07-09 12:38:05 +020041 int queued_cmds;
42 int done_cmds;
Jens Axboe3d6392c2007-07-09 12:38:05 +020043 wait_queue_head_t wq_done;
44 wait_queue_head_t wq_free;
FUJITA Tomonorid351af02007-07-09 12:40:35 +020045 char name[BUS_ID_SIZE];
Jens Axboe3d6392c2007-07-09 12:38:05 +020046 int max_queue;
47 unsigned long flags;
48};
49
50enum {
51 BSG_F_BLOCK = 1,
Jens Axboe3d6392c2007-07-09 12:38:05 +020052};
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
Harvey Harrison24c03d42008-05-01 04:35:17 -070060#define dprintk(fmt, args...) printk(KERN_ERR "%s: " fmt, __func__, ##args)
Jens Axboe3d6392c2007-07-09 12:38:05 +020061#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 Tomonoriabf54392008-08-16 14:10:05 +0900175 struct sg_io_v4 *hdr, struct bsg_device *bd,
176 int has_write_perm)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200177{
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900178 if (hdr->request_len > BLK_MAX_CDB) {
179 rq->cmd = kzalloc(hdr->request_len, GFP_KERNEL);
180 if (!rq->cmd)
181 return -ENOMEM;
182 }
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100183
184 if (copy_from_user(rq->cmd, (void *)(unsigned long)hdr->request,
185 hdr->request_len))
186 return -EFAULT;
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200187
188 if (hdr->subprotocol == BSG_SUB_PROTOCOL_SCSI_CMD) {
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900189 if (blk_verify_command(&q->cmd_filter, rq->cmd, has_write_perm))
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200190 return -EPERM;
191 } else if (!capable(CAP_SYS_RAWIO))
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100192 return -EPERM;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200193
194 /*
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100195 * fill in request structure
Jens Axboe3d6392c2007-07-09 12:38:05 +0200196 */
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100197 rq->cmd_len = hdr->request_len;
198 rq->cmd_type = REQ_TYPE_BLOCK_PC;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200199
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100200 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;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200205
206 return 0;
207}
208
209/*
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100210 * Check if sg_io_v4 from user is allowed and valid
211 */
212static int
Jens Axboe165125e2007-07-24 09:28:11 +0200213bsg_validate_sgv4_hdr(struct request_queue *q, struct sg_io_v4 *hdr, int *rw)
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100214{
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200215 int ret = 0;
216
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100217 if (hdr->guard != 'Q')
218 return -EINVAL;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100219 if (hdr->dout_xfer_len > (q->max_sectors << 9) ||
220 hdr->din_xfer_len > (q->max_sectors << 9))
221 return -EIO;
222
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200223 switch (hdr->protocol) {
224 case BSG_PROTOCOL_SCSI:
225 switch (hdr->subprotocol) {
226 case BSG_SUB_PROTOCOL_SCSI_CMD:
227 case BSG_SUB_PROTOCOL_SCSI_TRANSPORT:
228 break;
229 default:
230 ret = -EINVAL;
231 }
232 break;
233 default:
234 ret = -EINVAL;
235 }
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100236
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100237 *rw = hdr->dout_xfer_len ? WRITE : READ;
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200238 return ret;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100239}
240
241/*
242 * map sg_io_v4 to a request.
Jens Axboe3d6392c2007-07-09 12:38:05 +0200243 */
244static struct request *
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900245bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, int has_write_perm)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200246{
Jens Axboe165125e2007-07-24 09:28:11 +0200247 struct request_queue *q = bd->queue;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200248 struct request *rq, *next_rq = NULL;
Jens Axboe25fd1642007-07-17 08:52:29 +0200249 int ret, rw;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100250 unsigned int dxfer_len;
251 void *dxferp = NULL;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200252
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100253 dprintk("map hdr %llx/%u %llx/%u\n", (unsigned long long) hdr->dout_xferp,
254 hdr->dout_xfer_len, (unsigned long long) hdr->din_xferp,
255 hdr->din_xfer_len);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200256
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100257 ret = bsg_validate_sgv4_hdr(q, hdr, &rw);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200258 if (ret)
259 return ERR_PTR(ret);
260
261 /*
262 * map scatter-gather elements seperately and string them to request
263 */
264 rq = blk_get_request(q, rw, GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200265 if (!rq)
266 return ERR_PTR(-ENOMEM);
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900267 ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, bd, has_write_perm);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200268 if (ret)
269 goto out;
270
271 if (rw == WRITE && hdr->din_xfer_len) {
272 if (!test_bit(QUEUE_FLAG_BIDI, &q->queue_flags)) {
273 ret = -EOPNOTSUPP;
274 goto out;
275 }
276
277 next_rq = blk_get_request(q, READ, GFP_KERNEL);
278 if (!next_rq) {
279 ret = -ENOMEM;
280 goto out;
281 }
282 rq->next_rq = next_rq;
James Bottomley40f62022008-01-25 20:05:55 -0600283 next_rq->cmd_type = rq->cmd_type;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200284
285 dxferp = (void*)(unsigned long)hdr->din_xferp;
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900286 ret = blk_rq_map_user(q, next_rq, NULL, dxferp,
287 hdr->din_xfer_len, GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200288 if (ret)
289 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200290 }
291
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100292 if (hdr->dout_xfer_len) {
293 dxfer_len = hdr->dout_xfer_len;
294 dxferp = (void*)(unsigned long)hdr->dout_xferp;
295 } else if (hdr->din_xfer_len) {
296 dxfer_len = hdr->din_xfer_len;
297 dxferp = (void*)(unsigned long)hdr->din_xferp;
298 } else
299 dxfer_len = 0;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200300
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100301 if (dxfer_len) {
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900302 ret = blk_rq_map_user(q, rq, NULL, dxferp, dxfer_len,
303 GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200304 if (ret)
305 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200306 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200307 return rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200308out:
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900309 if (rq->cmd != rq->__cmd)
310 kfree(rq->cmd);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200311 blk_put_request(rq);
312 if (next_rq) {
313 blk_rq_unmap_user(next_rq->bio);
314 blk_put_request(next_rq);
315 }
316 return ERR_PTR(ret);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200317}
318
319/*
320 * async completion call-back from the block layer, when scsi/ide/whatever
321 * calls end_that_request_last() on a request
322 */
323static void bsg_rq_end_io(struct request *rq, int uptodate)
324{
325 struct bsg_command *bc = rq->end_io_data;
326 struct bsg_device *bd = bc->bd;
327 unsigned long flags;
328
Jens Axboe5309cb32007-01-23 16:24:41 +0100329 dprintk("%s: finished rq %p bc %p, bio %p stat %d\n",
330 bd->name, rq, bc, bc->bio, uptodate);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200331
332 bc->hdr.duration = jiffies_to_msecs(jiffies - bc->hdr.duration);
333
334 spin_lock_irqsave(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200335 list_move_tail(&bc->list, &bd->done_list);
336 bd->done_cmds++;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200337 spin_unlock_irqrestore(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200338
339 wake_up(&bd->wq_done);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200340}
341
342/*
343 * do final setup of a 'bc' and submit the matching 'rq' to the block
344 * layer for io
345 */
Jens Axboe165125e2007-07-24 09:28:11 +0200346static void bsg_add_command(struct bsg_device *bd, struct request_queue *q,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200347 struct bsg_command *bc, struct request *rq)
348{
349 rq->sense = bc->sense;
350 rq->sense_len = 0;
351
352 /*
353 * add bc command to busy queue and submit rq for io
354 */
355 bc->rq = rq;
356 bc->bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200357 if (rq->next_rq)
358 bc->bidi_bio = rq->next_rq->bio;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200359 bc->hdr.duration = jiffies;
360 spin_lock_irq(&bd->lock);
361 list_add_tail(&bc->list, &bd->busy_list);
362 spin_unlock_irq(&bd->lock);
363
364 dprintk("%s: queueing rq %p, bc %p\n", bd->name, rq, bc);
365
366 rq->end_io_data = bc;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200367 blk_execute_rq_nowait(q, NULL, rq, 1, bsg_rq_end_io);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200368}
369
Jens Axboe25fd1642007-07-17 08:52:29 +0200370static struct bsg_command *bsg_next_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200371{
372 struct bsg_command *bc = NULL;
373
374 spin_lock_irq(&bd->lock);
375 if (bd->done_cmds) {
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900376 bc = list_first_entry(&bd->done_list, struct bsg_command, list);
Jens Axboe25fd1642007-07-17 08:52:29 +0200377 list_del(&bc->list);
378 bd->done_cmds--;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200379 }
380 spin_unlock_irq(&bd->lock);
381
382 return bc;
383}
384
385/*
386 * Get a finished command from the done list
387 */
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200388static struct bsg_command *bsg_get_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200389{
390 struct bsg_command *bc;
391 int ret;
392
393 do {
394 bc = bsg_next_done_cmd(bd);
395 if (bc)
396 break;
397
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200398 if (!test_bit(BSG_F_BLOCK, &bd->flags)) {
399 bc = ERR_PTR(-EAGAIN);
400 break;
401 }
402
403 ret = wait_event_interruptible(bd->wq_done, bd->done_cmds);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200404 if (ret) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200405 bc = ERR_PTR(-ERESTARTSYS);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200406 break;
407 }
408 } while (1);
409
410 dprintk("%s: returning done %p\n", bd->name, bc);
411
412 return bc;
413}
414
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100415static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr,
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200416 struct bio *bio, struct bio *bidi_bio)
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100417{
418 int ret = 0;
419
420 dprintk("rq %p bio %p %u\n", rq, bio, rq->errors);
421 /*
422 * fill in all the output members
423 */
424 hdr->device_status = status_byte(rq->errors);
425 hdr->transport_status = host_byte(rq->errors);
426 hdr->driver_status = driver_byte(rq->errors);
427 hdr->info = 0;
428 if (hdr->device_status || hdr->transport_status || hdr->driver_status)
429 hdr->info |= SG_INFO_CHECK;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100430 hdr->response_len = 0;
431
432 if (rq->sense_len && hdr->response) {
Jens Axboe25fd1642007-07-17 08:52:29 +0200433 int len = min_t(unsigned int, hdr->max_response_len,
434 rq->sense_len);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100435
436 ret = copy_to_user((void*)(unsigned long)hdr->response,
437 rq->sense, len);
438 if (!ret)
439 hdr->response_len = len;
440 else
441 ret = -EFAULT;
442 }
443
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200444 if (rq->next_rq) {
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100445 hdr->dout_resid = rq->data_len;
446 hdr->din_resid = rq->next_rq->data_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200447 blk_rq_unmap_user(bidi_bio);
448 blk_put_request(rq->next_rq);
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900449 } else if (rq_data_dir(rq) == READ)
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100450 hdr->din_resid = rq->data_len;
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900451 else
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100452 hdr->dout_resid = rq->data_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200453
James Bottomley2d507a02007-12-29 10:59:53 -0600454 /*
455 * If the request generated a negative error number, return it
456 * (providing we aren't already returning an error); if it's
457 * just a protocol response (i.e. non negative), that gets
458 * processed above.
459 */
460 if (!ret && rq->errors < 0)
461 ret = rq->errors;
462
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100463 blk_rq_unmap_user(bio);
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900464 if (rq->cmd != rq->__cmd)
465 kfree(rq->cmd);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100466 blk_put_request(rq);
467
468 return ret;
469}
470
Jens Axboe3d6392c2007-07-09 12:38:05 +0200471static int bsg_complete_all_commands(struct bsg_device *bd)
472{
473 struct bsg_command *bc;
474 int ret, tret;
475
476 dprintk("%s: entered\n", bd->name);
477
Jens Axboe3d6392c2007-07-09 12:38:05 +0200478 /*
479 * wait for all commands to complete
480 */
481 ret = 0;
482 do {
Jens Axboe25fd1642007-07-17 08:52:29 +0200483 ret = bsg_io_schedule(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200484 /*
485 * look for -ENODATA specifically -- we'll sometimes get
486 * -ERESTARTSYS when we've taken a signal, but we can't
487 * return until we're done freeing the queue, so ignore
488 * it. The signal will get handled when we're done freeing
489 * the bsg_device.
490 */
491 } while (ret != -ENODATA);
492
493 /*
494 * discard done commands
495 */
496 ret = 0;
497 do {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200498 spin_lock_irq(&bd->lock);
499 if (!bd->queued_cmds) {
500 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200501 break;
502 }
FUJITA Tomonoriefba1a32007-06-07 13:24:06 +0200503 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200504
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200505 bc = bsg_get_done_cmd(bd);
506 if (IS_ERR(bc))
507 break;
508
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200509 tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
510 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200511 if (!ret)
512 ret = tret;
513
514 bsg_free_command(bc);
515 } while (1);
516
517 return ret;
518}
519
Jens Axboe25fd1642007-07-17 08:52:29 +0200520static int
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200521__bsg_read(char __user *buf, size_t count, struct bsg_device *bd,
522 const struct iovec *iov, ssize_t *bytes_read)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200523{
524 struct bsg_command *bc;
525 int nr_commands, ret;
526
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100527 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200528 return -EINVAL;
529
530 ret = 0;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100531 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200532 while (nr_commands) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200533 bc = bsg_get_done_cmd(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200534 if (IS_ERR(bc)) {
535 ret = PTR_ERR(bc);
536 break;
537 }
538
539 /*
540 * this is the only case where we need to copy data back
541 * after completing the request. so do that here,
542 * bsg_complete_work() cannot do that for us
543 */
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200544 ret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
545 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200546
Jens Axboe25fd1642007-07-17 08:52:29 +0200547 if (copy_to_user(buf, &bc->hdr, sizeof(bc->hdr)))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200548 ret = -EFAULT;
549
550 bsg_free_command(bc);
551
552 if (ret)
553 break;
554
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100555 buf += sizeof(struct sg_io_v4);
556 *bytes_read += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200557 nr_commands--;
558 }
559
560 return ret;
561}
562
563static inline void bsg_set_block(struct bsg_device *bd, struct file *file)
564{
565 if (file->f_flags & O_NONBLOCK)
566 clear_bit(BSG_F_BLOCK, &bd->flags);
567 else
568 set_bit(BSG_F_BLOCK, &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);
Adel Gadllah0b07de82008-06-26 13:48:27 +0200592
Jens Axboe3d6392c2007-07-09 12:38:05 +0200593 bytes_read = 0;
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200594 ret = __bsg_read(buf, count, bd, NULL, &bytes_read);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200595 *ppos = bytes_read;
596
597 if (!bytes_read || (bytes_read && err_block_err(ret)))
598 bytes_read = ret;
599
600 return bytes_read;
601}
602
Jens Axboe25fd1642007-07-17 08:52:29 +0200603static int __bsg_write(struct bsg_device *bd, const char __user *buf,
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900604 size_t count, ssize_t *bytes_written, int has_write_perm)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200605{
606 struct bsg_command *bc;
607 struct request *rq;
608 int ret, nr_commands;
609
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100610 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200611 return -EINVAL;
612
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100613 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200614 rq = NULL;
615 bc = NULL;
616 ret = 0;
617 while (nr_commands) {
Jens Axboe165125e2007-07-24 09:28:11 +0200618 struct request_queue *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200619
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200620 bc = bsg_alloc_command(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200621 if (IS_ERR(bc)) {
622 ret = PTR_ERR(bc);
623 bc = NULL;
624 break;
625 }
626
Jens Axboe3d6392c2007-07-09 12:38:05 +0200627 if (copy_from_user(&bc->hdr, buf, sizeof(bc->hdr))) {
628 ret = -EFAULT;
629 break;
630 }
631
632 /*
633 * get a request, fill in the blanks, and add to request queue
634 */
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900635 rq = bsg_map_hdr(bd, &bc->hdr, has_write_perm);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200636 if (IS_ERR(rq)) {
637 ret = PTR_ERR(rq);
638 rq = NULL;
639 break;
640 }
641
642 bsg_add_command(bd, q, bc, rq);
643 bc = NULL;
644 rq = NULL;
645 nr_commands--;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100646 buf += sizeof(struct sg_io_v4);
Jens Axboe25fd1642007-07-17 08:52:29 +0200647 *bytes_written += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200648 }
649
Jens Axboe3d6392c2007-07-09 12:38:05 +0200650 if (bc)
651 bsg_free_command(bc);
652
653 return ret;
654}
655
656static ssize_t
657bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
658{
659 struct bsg_device *bd = file->private_data;
Jens Axboe25fd1642007-07-17 08:52:29 +0200660 ssize_t bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200661 int ret;
662
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100663 dprintk("%s: write %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200664
665 bsg_set_block(bd, file);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200666
Jens Axboe25fd1642007-07-17 08:52:29 +0200667 bytes_written = 0;
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900668 ret = __bsg_write(bd, buf, count, &bytes_written,
669 file->f_mode & FMODE_WRITE);
670
Jens Axboe25fd1642007-07-17 08:52:29 +0200671 *ppos = bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200672
673 /*
674 * return bytes written on non-fatal errors
675 */
Jens Axboe25fd1642007-07-17 08:52:29 +0200676 if (!bytes_written || (bytes_written && err_block_err(ret)))
677 bytes_written = ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200678
Jens Axboe25fd1642007-07-17 08:52:29 +0200679 dprintk("%s: returning %Zd\n", bd->name, bytes_written);
680 return bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200681}
682
Jens Axboe3d6392c2007-07-09 12:38:05 +0200683static struct bsg_device *bsg_alloc_device(void)
684{
Jens Axboe3d6392c2007-07-09 12:38:05 +0200685 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200686
687 bd = kzalloc(sizeof(struct bsg_device), GFP_KERNEL);
688 if (unlikely(!bd))
689 return NULL;
690
691 spin_lock_init(&bd->lock);
692
Jens Axboe5309cb32007-01-23 16:24:41 +0100693 bd->max_queue = BSG_DEFAULT_CMDS;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200694
695 INIT_LIST_HEAD(&bd->busy_list);
696 INIT_LIST_HEAD(&bd->done_list);
697 INIT_HLIST_NODE(&bd->dev_list);
698
699 init_waitqueue_head(&bd->wq_free);
700 init_waitqueue_head(&bd->wq_done);
701 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200702}
703
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900704static void bsg_kref_release_function(struct kref *kref)
705{
706 struct bsg_class_device *bcd =
707 container_of(kref, struct bsg_class_device, ref);
James Bottomley8df5fc02008-07-07 15:50:01 -0500708 struct device *parent = bcd->parent;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900709
710 if (bcd->release)
711 bcd->release(bcd->parent);
712
James Bottomley8df5fc02008-07-07 15:50:01 -0500713 put_device(parent);
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900714}
715
Jens Axboe3d6392c2007-07-09 12:38:05 +0200716static int bsg_put_device(struct bsg_device *bd)
717{
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900718 int ret = 0, do_free;
719 struct request_queue *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200720
721 mutex_lock(&bsg_mutex);
722
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900723 do_free = atomic_dec_and_test(&bd->ref_count);
FUJITA Tomonori3f27e3e2008-05-29 07:56:55 +0900724 if (!do_free) {
725 mutex_unlock(&bsg_mutex);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200726 goto out;
FUJITA Tomonori3f27e3e2008-05-29 07:56:55 +0900727 }
728
729 hlist_del(&bd->dev_list);
730 mutex_unlock(&bsg_mutex);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200731
732 dprintk("%s: tearing down\n", bd->name);
733
734 /*
735 * close can always block
736 */
737 set_bit(BSG_F_BLOCK, &bd->flags);
738
739 /*
740 * correct error detection baddies here again. it's the responsibility
741 * of the app to properly reap commands before close() if it wants
742 * fool-proof error detection
743 */
744 ret = bsg_complete_all_commands(bd);
745
Jens Axboe5309cb32007-01-23 16:24:41 +0100746 kfree(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200747out:
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900748 kref_put(&q->bsg_dev.ref, bsg_kref_release_function);
749 if (do_free)
750 blk_put_queue(q);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200751 return ret;
752}
753
754static struct bsg_device *bsg_add_device(struct inode *inode,
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200755 struct request_queue *rq,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200756 struct file *file)
757{
Jens Axboe25fd1642007-07-17 08:52:29 +0200758 struct bsg_device *bd;
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900759 int ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200760#ifdef BSG_DEBUG
761 unsigned char buf[32];
762#endif
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900763 ret = blk_get_queue(rq);
764 if (ret)
765 return ERR_PTR(-ENXIO);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200766
767 bd = bsg_alloc_device();
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900768 if (!bd) {
769 blk_put_queue(rq);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200770 return ERR_PTR(-ENOMEM);
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900771 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200772
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200773 bd->queue = rq;
Adel Gadllah0b07de82008-06-26 13:48:27 +0200774
Jens Axboe3d6392c2007-07-09 12:38:05 +0200775 bsg_set_block(bd, file);
776
777 atomic_set(&bd->ref_count, 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200778 mutex_lock(&bsg_mutex);
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900779 hlist_add_head(&bd->dev_list, bsg_dev_idx_hash(iminor(inode)));
Jens Axboe3d6392c2007-07-09 12:38:05 +0200780
Tony Jonesee959b02008-02-22 00:13:36 +0100781 strncpy(bd->name, rq->bsg_dev.class_dev->bus_id, sizeof(bd->name) - 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200782 dprintk("bound to <%s>, max queue %d\n",
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100783 format_dev_t(buf, inode->i_rdev), bd->max_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200784
785 mutex_unlock(&bsg_mutex);
786 return bd;
787}
788
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900789static struct bsg_device *__bsg_get_device(int minor, struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200790{
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900791 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200792 struct hlist_node *entry;
793
794 mutex_lock(&bsg_mutex);
795
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900796 hlist_for_each_entry(bd, entry, bsg_dev_idx_hash(minor), dev_list) {
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900797 if (bd->queue == q) {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200798 atomic_inc(&bd->ref_count);
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900799 goto found;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200800 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200801 }
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900802 bd = NULL;
803found:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200804 mutex_unlock(&bsg_mutex);
805 return bd;
806}
807
808static struct bsg_device *bsg_get_device(struct inode *inode, struct file *file)
809{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900810 struct bsg_device *bd;
811 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200812
Jens Axboe3d6392c2007-07-09 12:38:05 +0200813 /*
814 * find the class device
815 */
Jens Axboe3d6392c2007-07-09 12:38:05 +0200816 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900817 bcd = idr_find(&bsg_minor_idr, iminor(inode));
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900818 if (bcd)
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900819 kref_get(&bcd->ref);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200820 mutex_unlock(&bsg_mutex);
821
822 if (!bcd)
823 return ERR_PTR(-ENODEV);
824
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900825 bd = __bsg_get_device(iminor(inode), bcd->queue);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900826 if (bd)
827 return bd;
828
829 bd = bsg_add_device(inode, bcd->queue, file);
830 if (IS_ERR(bd))
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900831 kref_put(&bcd->ref, bsg_kref_release_function);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900832
833 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200834}
835
836static int bsg_open(struct inode *inode, struct file *file)
837{
Jonathan Corbet75bd2ef2008-05-15 09:09:23 -0600838 struct bsg_device *bd;
839
840 lock_kernel();
841 bd = bsg_get_device(inode, file);
842 unlock_kernel();
Jens Axboe3d6392c2007-07-09 12:38:05 +0200843
844 if (IS_ERR(bd))
845 return PTR_ERR(bd);
846
847 file->private_data = bd;
848 return 0;
849}
850
851static int bsg_release(struct inode *inode, struct file *file)
852{
853 struct bsg_device *bd = file->private_data;
854
855 file->private_data = NULL;
856 return bsg_put_device(bd);
857}
858
859static unsigned int bsg_poll(struct file *file, poll_table *wait)
860{
861 struct bsg_device *bd = file->private_data;
862 unsigned int mask = 0;
863
864 poll_wait(file, &bd->wq_done, wait);
865 poll_wait(file, &bd->wq_free, wait);
866
867 spin_lock_irq(&bd->lock);
868 if (!list_empty(&bd->done_list))
869 mask |= POLLIN | POLLRDNORM;
870 if (bd->queued_cmds >= bd->max_queue)
871 mask |= POLLOUT;
872 spin_unlock_irq(&bd->lock);
873
874 return mask;
875}
876
Jens Axboe25fd1642007-07-17 08:52:29 +0200877static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200878{
879 struct bsg_device *bd = file->private_data;
880 int __user *uarg = (int __user *) arg;
James Bottomley2d507a02007-12-29 10:59:53 -0600881 int ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200882
Jens Axboe3d6392c2007-07-09 12:38:05 +0200883 switch (cmd) {
884 /*
885 * our own ioctls
886 */
887 case SG_GET_COMMAND_Q:
888 return put_user(bd->max_queue, uarg);
Jens Axboe5309cb32007-01-23 16:24:41 +0100889 case SG_SET_COMMAND_Q: {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200890 int queue;
891
892 if (get_user(queue, uarg))
893 return -EFAULT;
Jens Axboe5309cb32007-01-23 16:24:41 +0100894 if (queue < 1)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200895 return -EINVAL;
896
Jens Axboe5309cb32007-01-23 16:24:41 +0100897 spin_lock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200898 bd->max_queue = queue;
Jens Axboe5309cb32007-01-23 16:24:41 +0100899 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200900 return 0;
901 }
902
903 /*
904 * SCSI/sg ioctls
905 */
906 case SG_GET_VERSION_NUM:
907 case SCSI_IOCTL_GET_IDLUN:
908 case SCSI_IOCTL_GET_BUS_NUMBER:
909 case SG_SET_TIMEOUT:
910 case SG_GET_TIMEOUT:
911 case SG_GET_RESERVED_SIZE:
912 case SG_SET_RESERVED_SIZE:
913 case SG_EMULATED_HOST:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200914 case SCSI_IOCTL_SEND_COMMAND: {
915 void __user *uarg = (void __user *) arg;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200916 return scsi_cmd_ioctl(file, bd->queue, NULL, cmd, uarg);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200917 }
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100918 case SG_IO: {
919 struct request *rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200920 struct bio *bio, *bidi_bio = NULL;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100921 struct sg_io_v4 hdr;
922
923 if (copy_from_user(&hdr, uarg, sizeof(hdr)))
924 return -EFAULT;
925
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900926 rq = bsg_map_hdr(bd, &hdr, file->f_mode & FMODE_WRITE);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100927 if (IS_ERR(rq))
928 return PTR_ERR(rq);
929
930 bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200931 if (rq->next_rq)
932 bidi_bio = rq->next_rq->bio;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200933 blk_execute_rq(bd->queue, NULL, rq, 0);
James Bottomley2d507a02007-12-29 10:59:53 -0600934 ret = blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100935
936 if (copy_to_user(uarg, &hdr, sizeof(hdr)))
937 return -EFAULT;
Jens Axboeb711afa2006-12-20 11:25:23 +0100938
James Bottomley2d507a02007-12-29 10:59:53 -0600939 return ret;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100940 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200941 /*
942 * block device ioctls
943 */
944 default:
945#if 0
946 return ioctl_by_bdev(bd->bdev, cmd, arg);
947#else
948 return -ENOTTY;
949#endif
950 }
951}
952
Arjan van de Ven7344be02007-10-15 11:01:53 +0200953static const struct file_operations bsg_fops = {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200954 .read = bsg_read,
955 .write = bsg_write,
956 .poll = bsg_poll,
957 .open = bsg_open,
958 .release = bsg_release,
Jens Axboe25fd1642007-07-17 08:52:29 +0200959 .unlocked_ioctl = bsg_ioctl,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200960 .owner = THIS_MODULE,
961};
962
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200963void bsg_unregister_queue(struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200964{
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200965 struct bsg_class_device *bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200966
FUJITA Tomonoridf468822007-07-21 13:23:25 +0900967 if (!bcd->class_dev)
968 return;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200969
970 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900971 idr_remove(&bsg_minor_idr, bcd->minor);
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200972 sysfs_remove_link(&q->kobj, "bsg");
Tony Jonesee959b02008-02-22 00:13:36 +0100973 device_unregister(bcd->class_dev);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200974 bcd->class_dev = NULL;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900975 kref_put(&bcd->ref, bsg_kref_release_function);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200976 mutex_unlock(&bsg_mutex);
977}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +0200978EXPORT_SYMBOL_GPL(bsg_unregister_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200979
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900980int bsg_register_queue(struct request_queue *q, struct device *parent,
981 const char *name, void (*release)(struct device *))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200982{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900983 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200984 dev_t dev;
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900985 int ret, minor;
Tony Jonesee959b02008-02-22 00:13:36 +0100986 struct device *class_dev = NULL;
James Bottomley39dca552007-07-20 18:22:17 -0500987 const char *devname;
988
989 if (name)
990 devname = name;
991 else
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900992 devname = parent->bus_id;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200993
994 /*
995 * we need a proper transport to send commands, not a stacked device
996 */
997 if (!q->request_fn)
998 return 0;
999
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001000 bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001001 memset(bcd, 0, sizeof(*bcd));
Jens Axboe3d6392c2007-07-09 12:38:05 +02001002
1003 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001004
1005 ret = idr_pre_get(&bsg_minor_idr, GFP_KERNEL);
1006 if (!ret) {
1007 ret = -ENOMEM;
1008 goto unlock;
1009 }
1010
1011 ret = idr_get_new(&bsg_minor_idr, bcd, &minor);
1012 if (ret < 0)
1013 goto unlock;
1014
1015 if (minor >= BSG_MAX_DEVS) {
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001016 printk(KERN_ERR "bsg: too many bsg devices\n");
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001017 ret = -EINVAL;
1018 goto remove_idr;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001019 }
1020
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001021 bcd->minor = minor;
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001022 bcd->queue = q;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001023 bcd->parent = get_device(parent);
1024 bcd->release = release;
1025 kref_init(&bcd->ref);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001026 dev = MKDEV(bsg_major, bcd->minor);
Greg Kroah-Hartman1ff9f542008-07-21 20:03:34 -07001027 class_dev = device_create(bsg_class, parent, dev, NULL, "%s", devname);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001028 if (IS_ERR(class_dev)) {
1029 ret = PTR_ERR(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001030 goto put_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001031 }
1032 bcd->class_dev = class_dev;
1033
Linus Torvaldsabce8912007-07-16 11:18:23 -07001034 if (q->kobj.sd) {
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001035 ret = sysfs_create_link(&q->kobj, &bcd->class_dev->kobj, "bsg");
1036 if (ret)
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001037 goto unregister_class_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001038 }
1039
Jens Axboe3d6392c2007-07-09 12:38:05 +02001040 mutex_unlock(&bsg_mutex);
1041 return 0;
James Bottomley6826ee42007-07-20 16:50:10 -05001042
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001043unregister_class_dev:
Tony Jonesee959b02008-02-22 00:13:36 +01001044 device_unregister(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001045put_dev:
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001046 put_device(parent);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001047remove_idr:
1048 idr_remove(&bsg_minor_idr, minor);
1049unlock:
Jens Axboe264a0472007-01-23 16:30:17 +01001050 mutex_unlock(&bsg_mutex);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001051 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001052}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +02001053EXPORT_SYMBOL_GPL(bsg_register_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001054
Greg Kroah-Hartman7e7654a2007-09-12 15:06:57 -07001055static struct cdev bsg_cdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001056
Jens Axboe3d6392c2007-07-09 12:38:05 +02001057static int __init bsg_init(void)
1058{
1059 int ret, i;
Jens Axboe46f6ef42007-07-17 08:56:10 +02001060 dev_t devid;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001061
Jens Axboe5309cb32007-01-23 16:24:41 +01001062 bsg_cmd_cachep = kmem_cache_create("bsg_cmd",
Paul Mundt20c2df82007-07-20 10:11:58 +09001063 sizeof(struct bsg_command), 0, 0, NULL);
Jens Axboe5309cb32007-01-23 16:24:41 +01001064 if (!bsg_cmd_cachep) {
1065 printk(KERN_ERR "bsg: failed creating slab cache\n");
1066 return -ENOMEM;
1067 }
1068
Jens Axboe25fd1642007-07-17 08:52:29 +02001069 for (i = 0; i < BSG_LIST_ARRAY_SIZE; i++)
Jens Axboe3d6392c2007-07-09 12:38:05 +02001070 INIT_HLIST_HEAD(&bsg_device_list[i]);
1071
1072 bsg_class = class_create(THIS_MODULE, "bsg");
Jens Axboe5309cb32007-01-23 16:24:41 +01001073 if (IS_ERR(bsg_class)) {
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001074 ret = PTR_ERR(bsg_class);
1075 goto destroy_kmemcache;
Jens Axboe5309cb32007-01-23 16:24:41 +01001076 }
Jens Axboe3d6392c2007-07-09 12:38:05 +02001077
Jens Axboe46f6ef42007-07-17 08:56:10 +02001078 ret = alloc_chrdev_region(&devid, 0, BSG_MAX_DEVS, "bsg");
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001079 if (ret)
1080 goto destroy_bsg_class;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001081
Jens Axboe46f6ef42007-07-17 08:56:10 +02001082 bsg_major = MAJOR(devid);
1083
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001084 cdev_init(&bsg_cdev, &bsg_fops);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001085 ret = cdev_add(&bsg_cdev, MKDEV(bsg_major, 0), BSG_MAX_DEVS);
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001086 if (ret)
1087 goto unregister_chrdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001088
Jens Axboe5d3a8cd2007-07-17 15:10:09 +02001089 printk(KERN_INFO BSG_DESCRIPTION " version " BSG_VERSION
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001090 " loaded (major %d)\n", bsg_major);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001091 return 0;
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001092unregister_chrdev:
1093 unregister_chrdev_region(MKDEV(bsg_major, 0), BSG_MAX_DEVS);
1094destroy_bsg_class:
1095 class_destroy(bsg_class);
1096destroy_kmemcache:
1097 kmem_cache_destroy(bsg_cmd_cachep);
1098 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001099}
1100
1101MODULE_AUTHOR("Jens Axboe");
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001102MODULE_DESCRIPTION(BSG_DESCRIPTION);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001103MODULE_LICENSE("GPL");
1104
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001105device_initcall(bsg_init);