blob: e8bd2475682ab4c2d29f8f205e57b62427b7cfe2 [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,
Al Viroaeb5d722008-09-02 15:28:45 -0400176 fmode_t 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 *
Al Viroaeb5d722008-09-02 15:28:45 -0400245bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t 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,
Al Viroaeb5d722008-09-02 15:28:45 -0400604 size_t count, ssize_t *bytes_written,
605 fmode_t has_write_perm)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200606{
607 struct bsg_command *bc;
608 struct request *rq;
609 int ret, nr_commands;
610
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100611 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200612 return -EINVAL;
613
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100614 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200615 rq = NULL;
616 bc = NULL;
617 ret = 0;
618 while (nr_commands) {
Jens Axboe165125e2007-07-24 09:28:11 +0200619 struct request_queue *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200620
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200621 bc = bsg_alloc_command(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200622 if (IS_ERR(bc)) {
623 ret = PTR_ERR(bc);
624 bc = NULL;
625 break;
626 }
627
Jens Axboe3d6392c2007-07-09 12:38:05 +0200628 if (copy_from_user(&bc->hdr, buf, sizeof(bc->hdr))) {
629 ret = -EFAULT;
630 break;
631 }
632
633 /*
634 * get a request, fill in the blanks, and add to request queue
635 */
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900636 rq = bsg_map_hdr(bd, &bc->hdr, has_write_perm);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200637 if (IS_ERR(rq)) {
638 ret = PTR_ERR(rq);
639 rq = NULL;
640 break;
641 }
642
643 bsg_add_command(bd, q, bc, rq);
644 bc = NULL;
645 rq = NULL;
646 nr_commands--;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100647 buf += sizeof(struct sg_io_v4);
Jens Axboe25fd1642007-07-17 08:52:29 +0200648 *bytes_written += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200649 }
650
Jens Axboe3d6392c2007-07-09 12:38:05 +0200651 if (bc)
652 bsg_free_command(bc);
653
654 return ret;
655}
656
657static ssize_t
658bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
659{
660 struct bsg_device *bd = file->private_data;
Jens Axboe25fd1642007-07-17 08:52:29 +0200661 ssize_t bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200662 int ret;
663
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100664 dprintk("%s: write %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200665
666 bsg_set_block(bd, file);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200667
Jens Axboe25fd1642007-07-17 08:52:29 +0200668 bytes_written = 0;
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900669 ret = __bsg_write(bd, buf, count, &bytes_written,
670 file->f_mode & FMODE_WRITE);
671
Jens Axboe25fd1642007-07-17 08:52:29 +0200672 *ppos = bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200673
674 /*
675 * return bytes written on non-fatal errors
676 */
Jens Axboe25fd1642007-07-17 08:52:29 +0200677 if (!bytes_written || (bytes_written && err_block_err(ret)))
678 bytes_written = ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200679
Jens Axboe25fd1642007-07-17 08:52:29 +0200680 dprintk("%s: returning %Zd\n", bd->name, bytes_written);
681 return bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200682}
683
Jens Axboe3d6392c2007-07-09 12:38:05 +0200684static struct bsg_device *bsg_alloc_device(void)
685{
Jens Axboe3d6392c2007-07-09 12:38:05 +0200686 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200687
688 bd = kzalloc(sizeof(struct bsg_device), GFP_KERNEL);
689 if (unlikely(!bd))
690 return NULL;
691
692 spin_lock_init(&bd->lock);
693
Jens Axboe5309cb32007-01-23 16:24:41 +0100694 bd->max_queue = BSG_DEFAULT_CMDS;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200695
696 INIT_LIST_HEAD(&bd->busy_list);
697 INIT_LIST_HEAD(&bd->done_list);
698 INIT_HLIST_NODE(&bd->dev_list);
699
700 init_waitqueue_head(&bd->wq_free);
701 init_waitqueue_head(&bd->wq_done);
702 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200703}
704
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900705static void bsg_kref_release_function(struct kref *kref)
706{
707 struct bsg_class_device *bcd =
708 container_of(kref, struct bsg_class_device, ref);
James Bottomley8df5fc02008-07-07 15:50:01 -0500709 struct device *parent = bcd->parent;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900710
711 if (bcd->release)
712 bcd->release(bcd->parent);
713
James Bottomley8df5fc02008-07-07 15:50:01 -0500714 put_device(parent);
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900715}
716
Jens Axboe3d6392c2007-07-09 12:38:05 +0200717static int bsg_put_device(struct bsg_device *bd)
718{
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900719 int ret = 0, do_free;
720 struct request_queue *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200721
722 mutex_lock(&bsg_mutex);
723
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900724 do_free = atomic_dec_and_test(&bd->ref_count);
FUJITA Tomonori3f27e3e2008-05-29 07:56:55 +0900725 if (!do_free) {
726 mutex_unlock(&bsg_mutex);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200727 goto out;
FUJITA Tomonori3f27e3e2008-05-29 07:56:55 +0900728 }
729
730 hlist_del(&bd->dev_list);
731 mutex_unlock(&bsg_mutex);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200732
733 dprintk("%s: tearing down\n", bd->name);
734
735 /*
736 * close can always block
737 */
738 set_bit(BSG_F_BLOCK, &bd->flags);
739
740 /*
741 * correct error detection baddies here again. it's the responsibility
742 * of the app to properly reap commands before close() if it wants
743 * fool-proof error detection
744 */
745 ret = bsg_complete_all_commands(bd);
746
Jens Axboe5309cb32007-01-23 16:24:41 +0100747 kfree(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200748out:
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900749 kref_put(&q->bsg_dev.ref, bsg_kref_release_function);
750 if (do_free)
751 blk_put_queue(q);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200752 return ret;
753}
754
755static struct bsg_device *bsg_add_device(struct inode *inode,
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200756 struct request_queue *rq,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200757 struct file *file)
758{
Jens Axboe25fd1642007-07-17 08:52:29 +0200759 struct bsg_device *bd;
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900760 int ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200761#ifdef BSG_DEBUG
762 unsigned char buf[32];
763#endif
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900764 ret = blk_get_queue(rq);
765 if (ret)
766 return ERR_PTR(-ENXIO);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200767
768 bd = bsg_alloc_device();
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900769 if (!bd) {
770 blk_put_queue(rq);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200771 return ERR_PTR(-ENOMEM);
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900772 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200773
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200774 bd->queue = rq;
Adel Gadllah0b07de82008-06-26 13:48:27 +0200775
Jens Axboe3d6392c2007-07-09 12:38:05 +0200776 bsg_set_block(bd, file);
777
778 atomic_set(&bd->ref_count, 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200779 mutex_lock(&bsg_mutex);
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900780 hlist_add_head(&bd->dev_list, bsg_dev_idx_hash(iminor(inode)));
Jens Axboe3d6392c2007-07-09 12:38:05 +0200781
Tony Jonesee959b02008-02-22 00:13:36 +0100782 strncpy(bd->name, rq->bsg_dev.class_dev->bus_id, sizeof(bd->name) - 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200783 dprintk("bound to <%s>, max queue %d\n",
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100784 format_dev_t(buf, inode->i_rdev), bd->max_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200785
786 mutex_unlock(&bsg_mutex);
787 return bd;
788}
789
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900790static struct bsg_device *__bsg_get_device(int minor, struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200791{
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900792 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200793 struct hlist_node *entry;
794
795 mutex_lock(&bsg_mutex);
796
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900797 hlist_for_each_entry(bd, entry, bsg_dev_idx_hash(minor), dev_list) {
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900798 if (bd->queue == q) {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200799 atomic_inc(&bd->ref_count);
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900800 goto found;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200801 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200802 }
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900803 bd = NULL;
804found:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200805 mutex_unlock(&bsg_mutex);
806 return bd;
807}
808
809static struct bsg_device *bsg_get_device(struct inode *inode, struct file *file)
810{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900811 struct bsg_device *bd;
812 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200813
Jens Axboe3d6392c2007-07-09 12:38:05 +0200814 /*
815 * find the class device
816 */
Jens Axboe3d6392c2007-07-09 12:38:05 +0200817 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900818 bcd = idr_find(&bsg_minor_idr, iminor(inode));
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900819 if (bcd)
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900820 kref_get(&bcd->ref);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200821 mutex_unlock(&bsg_mutex);
822
823 if (!bcd)
824 return ERR_PTR(-ENODEV);
825
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900826 bd = __bsg_get_device(iminor(inode), bcd->queue);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900827 if (bd)
828 return bd;
829
830 bd = bsg_add_device(inode, bcd->queue, file);
831 if (IS_ERR(bd))
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900832 kref_put(&bcd->ref, bsg_kref_release_function);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900833
834 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200835}
836
837static int bsg_open(struct inode *inode, struct file *file)
838{
Jonathan Corbet75bd2ef2008-05-15 09:09:23 -0600839 struct bsg_device *bd;
840
841 lock_kernel();
842 bd = bsg_get_device(inode, file);
843 unlock_kernel();
Jens Axboe3d6392c2007-07-09 12:38:05 +0200844
845 if (IS_ERR(bd))
846 return PTR_ERR(bd);
847
848 file->private_data = bd;
849 return 0;
850}
851
852static int bsg_release(struct inode *inode, struct file *file)
853{
854 struct bsg_device *bd = file->private_data;
855
856 file->private_data = NULL;
857 return bsg_put_device(bd);
858}
859
860static unsigned int bsg_poll(struct file *file, poll_table *wait)
861{
862 struct bsg_device *bd = file->private_data;
863 unsigned int mask = 0;
864
865 poll_wait(file, &bd->wq_done, wait);
866 poll_wait(file, &bd->wq_free, wait);
867
868 spin_lock_irq(&bd->lock);
869 if (!list_empty(&bd->done_list))
870 mask |= POLLIN | POLLRDNORM;
871 if (bd->queued_cmds >= bd->max_queue)
872 mask |= POLLOUT;
873 spin_unlock_irq(&bd->lock);
874
875 return mask;
876}
877
Jens Axboe25fd1642007-07-17 08:52:29 +0200878static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200879{
880 struct bsg_device *bd = file->private_data;
881 int __user *uarg = (int __user *) arg;
James Bottomley2d507a02007-12-29 10:59:53 -0600882 int ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200883
Jens Axboe3d6392c2007-07-09 12:38:05 +0200884 switch (cmd) {
885 /*
886 * our own ioctls
887 */
888 case SG_GET_COMMAND_Q:
889 return put_user(bd->max_queue, uarg);
Jens Axboe5309cb32007-01-23 16:24:41 +0100890 case SG_SET_COMMAND_Q: {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200891 int queue;
892
893 if (get_user(queue, uarg))
894 return -EFAULT;
Jens Axboe5309cb32007-01-23 16:24:41 +0100895 if (queue < 1)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200896 return -EINVAL;
897
Jens Axboe5309cb32007-01-23 16:24:41 +0100898 spin_lock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200899 bd->max_queue = queue;
Jens Axboe5309cb32007-01-23 16:24:41 +0100900 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200901 return 0;
902 }
903
904 /*
905 * SCSI/sg ioctls
906 */
907 case SG_GET_VERSION_NUM:
908 case SCSI_IOCTL_GET_IDLUN:
909 case SCSI_IOCTL_GET_BUS_NUMBER:
910 case SG_SET_TIMEOUT:
911 case SG_GET_TIMEOUT:
912 case SG_GET_RESERVED_SIZE:
913 case SG_SET_RESERVED_SIZE:
914 case SG_EMULATED_HOST:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200915 case SCSI_IOCTL_SEND_COMMAND: {
916 void __user *uarg = (void __user *) arg;
Al Viro74f3c8a2007-08-27 15:38:10 -0400917 return scsi_cmd_ioctl(bd->queue, NULL, file->f_mode, cmd, uarg);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200918 }
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100919 case SG_IO: {
920 struct request *rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200921 struct bio *bio, *bidi_bio = NULL;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100922 struct sg_io_v4 hdr;
923
924 if (copy_from_user(&hdr, uarg, sizeof(hdr)))
925 return -EFAULT;
926
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900927 rq = bsg_map_hdr(bd, &hdr, file->f_mode & FMODE_WRITE);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100928 if (IS_ERR(rq))
929 return PTR_ERR(rq);
930
931 bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200932 if (rq->next_rq)
933 bidi_bio = rq->next_rq->bio;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200934 blk_execute_rq(bd->queue, NULL, rq, 0);
James Bottomley2d507a02007-12-29 10:59:53 -0600935 ret = blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100936
937 if (copy_to_user(uarg, &hdr, sizeof(hdr)))
938 return -EFAULT;
Jens Axboeb711afa2006-12-20 11:25:23 +0100939
James Bottomley2d507a02007-12-29 10:59:53 -0600940 return ret;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100941 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200942 /*
943 * block device ioctls
944 */
945 default:
946#if 0
947 return ioctl_by_bdev(bd->bdev, cmd, arg);
948#else
949 return -ENOTTY;
950#endif
951 }
952}
953
Arjan van de Ven7344be02007-10-15 11:01:53 +0200954static const struct file_operations bsg_fops = {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200955 .read = bsg_read,
956 .write = bsg_write,
957 .poll = bsg_poll,
958 .open = bsg_open,
959 .release = bsg_release,
Jens Axboe25fd1642007-07-17 08:52:29 +0200960 .unlocked_ioctl = bsg_ioctl,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200961 .owner = THIS_MODULE,
962};
963
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200964void bsg_unregister_queue(struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200965{
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200966 struct bsg_class_device *bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200967
FUJITA Tomonoridf468822007-07-21 13:23:25 +0900968 if (!bcd->class_dev)
969 return;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200970
971 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900972 idr_remove(&bsg_minor_idr, bcd->minor);
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200973 sysfs_remove_link(&q->kobj, "bsg");
Tony Jonesee959b02008-02-22 00:13:36 +0100974 device_unregister(bcd->class_dev);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200975 bcd->class_dev = NULL;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900976 kref_put(&bcd->ref, bsg_kref_release_function);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200977 mutex_unlock(&bsg_mutex);
978}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +0200979EXPORT_SYMBOL_GPL(bsg_unregister_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200980
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900981int bsg_register_queue(struct request_queue *q, struct device *parent,
982 const char *name, void (*release)(struct device *))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200983{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900984 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200985 dev_t dev;
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900986 int ret, minor;
Tony Jonesee959b02008-02-22 00:13:36 +0100987 struct device *class_dev = NULL;
James Bottomley39dca552007-07-20 18:22:17 -0500988 const char *devname;
989
990 if (name)
991 devname = name;
992 else
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900993 devname = parent->bus_id;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200994
995 /*
996 * we need a proper transport to send commands, not a stacked device
997 */
998 if (!q->request_fn)
999 return 0;
1000
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001001 bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001002 memset(bcd, 0, sizeof(*bcd));
Jens Axboe3d6392c2007-07-09 12:38:05 +02001003
1004 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001005
1006 ret = idr_pre_get(&bsg_minor_idr, GFP_KERNEL);
1007 if (!ret) {
1008 ret = -ENOMEM;
1009 goto unlock;
1010 }
1011
1012 ret = idr_get_new(&bsg_minor_idr, bcd, &minor);
1013 if (ret < 0)
1014 goto unlock;
1015
1016 if (minor >= BSG_MAX_DEVS) {
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001017 printk(KERN_ERR "bsg: too many bsg devices\n");
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001018 ret = -EINVAL;
1019 goto remove_idr;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001020 }
1021
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001022 bcd->minor = minor;
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001023 bcd->queue = q;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001024 bcd->parent = get_device(parent);
1025 bcd->release = release;
1026 kref_init(&bcd->ref);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001027 dev = MKDEV(bsg_major, bcd->minor);
Greg Kroah-Hartman1ff9f542008-07-21 20:03:34 -07001028 class_dev = device_create(bsg_class, parent, dev, NULL, "%s", devname);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001029 if (IS_ERR(class_dev)) {
1030 ret = PTR_ERR(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001031 goto put_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001032 }
1033 bcd->class_dev = class_dev;
1034
Linus Torvaldsabce8912007-07-16 11:18:23 -07001035 if (q->kobj.sd) {
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001036 ret = sysfs_create_link(&q->kobj, &bcd->class_dev->kobj, "bsg");
1037 if (ret)
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001038 goto unregister_class_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001039 }
1040
Jens Axboe3d6392c2007-07-09 12:38:05 +02001041 mutex_unlock(&bsg_mutex);
1042 return 0;
James Bottomley6826ee42007-07-20 16:50:10 -05001043
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001044unregister_class_dev:
Tony Jonesee959b02008-02-22 00:13:36 +01001045 device_unregister(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001046put_dev:
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001047 put_device(parent);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001048remove_idr:
1049 idr_remove(&bsg_minor_idr, minor);
1050unlock:
Jens Axboe264a0472007-01-23 16:30:17 +01001051 mutex_unlock(&bsg_mutex);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001052 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001053}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +02001054EXPORT_SYMBOL_GPL(bsg_register_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001055
Greg Kroah-Hartman7e7654a2007-09-12 15:06:57 -07001056static struct cdev bsg_cdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001057
Jens Axboe3d6392c2007-07-09 12:38:05 +02001058static int __init bsg_init(void)
1059{
1060 int ret, i;
Jens Axboe46f6ef42007-07-17 08:56:10 +02001061 dev_t devid;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001062
Jens Axboe5309cb32007-01-23 16:24:41 +01001063 bsg_cmd_cachep = kmem_cache_create("bsg_cmd",
Paul Mundt20c2df82007-07-20 10:11:58 +09001064 sizeof(struct bsg_command), 0, 0, NULL);
Jens Axboe5309cb32007-01-23 16:24:41 +01001065 if (!bsg_cmd_cachep) {
1066 printk(KERN_ERR "bsg: failed creating slab cache\n");
1067 return -ENOMEM;
1068 }
1069
Jens Axboe25fd1642007-07-17 08:52:29 +02001070 for (i = 0; i < BSG_LIST_ARRAY_SIZE; i++)
Jens Axboe3d6392c2007-07-09 12:38:05 +02001071 INIT_HLIST_HEAD(&bsg_device_list[i]);
1072
1073 bsg_class = class_create(THIS_MODULE, "bsg");
Jens Axboe5309cb32007-01-23 16:24:41 +01001074 if (IS_ERR(bsg_class)) {
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001075 ret = PTR_ERR(bsg_class);
1076 goto destroy_kmemcache;
Jens Axboe5309cb32007-01-23 16:24:41 +01001077 }
Jens Axboe3d6392c2007-07-09 12:38:05 +02001078
Jens Axboe46f6ef42007-07-17 08:56:10 +02001079 ret = alloc_chrdev_region(&devid, 0, BSG_MAX_DEVS, "bsg");
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001080 if (ret)
1081 goto destroy_bsg_class;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001082
Jens Axboe46f6ef42007-07-17 08:56:10 +02001083 bsg_major = MAJOR(devid);
1084
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001085 cdev_init(&bsg_cdev, &bsg_fops);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001086 ret = cdev_add(&bsg_cdev, MKDEV(bsg_major, 0), BSG_MAX_DEVS);
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001087 if (ret)
1088 goto unregister_chrdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001089
Jens Axboe5d3a8cd2007-07-17 15:10:09 +02001090 printk(KERN_INFO BSG_DESCRIPTION " version " BSG_VERSION
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001091 " loaded (major %d)\n", bsg_major);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001092 return 0;
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001093unregister_chrdev:
1094 unregister_chrdev_region(MKDEV(bsg_major, 0), BSG_MAX_DEVS);
1095destroy_bsg_class:
1096 class_destroy(bsg_class);
1097destroy_kmemcache:
1098 kmem_cache_destroy(bsg_cmd_cachep);
1099 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001100}
1101
1102MODULE_AUTHOR("Jens Axboe");
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001103MODULE_DESCRIPTION(BSG_DESCRIPTION);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001104MODULE_LICENSE("GPL");
1105
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001106device_initcall(bsg_init);