blob: 5f184bb3ff9e12a13a0e01060c77bdc6e6bdc5e9 [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;
Kay Sievers3ada8b72009-01-06 10:44:43 -080045 char name[20];
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) {
Jens Axboe018e0442009-06-26 16:27:10 +0200189 if (blk_verify_command(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;
Linus Torvaldsf2f1fa72008-12-05 14:49:18 -0800205 if (rq->timeout < BLK_MIN_SG_TIMEOUT)
206 rq->timeout = BLK_MIN_SG_TIMEOUT;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200207
208 return 0;
209}
210
211/*
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100212 * Check if sg_io_v4 from user is allowed and valid
213 */
214static int
Jens Axboe165125e2007-07-24 09:28:11 +0200215bsg_validate_sgv4_hdr(struct request_queue *q, struct sg_io_v4 *hdr, int *rw)
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100216{
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200217 int ret = 0;
218
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100219 if (hdr->guard != 'Q')
220 return -EINVAL;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100221
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200222 switch (hdr->protocol) {
223 case BSG_PROTOCOL_SCSI:
224 switch (hdr->subprotocol) {
225 case BSG_SUB_PROTOCOL_SCSI_CMD:
226 case BSG_SUB_PROTOCOL_SCSI_TRANSPORT:
227 break;
228 default:
229 ret = -EINVAL;
230 }
231 break;
232 default:
233 ret = -EINVAL;
234 }
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100235
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100236 *rw = hdr->dout_xfer_len ? WRITE : READ;
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200237 return ret;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100238}
239
240/*
241 * map sg_io_v4 to a request.
Jens Axboe3d6392c2007-07-09 12:38:05 +0200242 */
243static struct request *
Boaz Harroshc1c201202009-02-03 07:47:29 +0100244bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t has_write_perm,
245 u8 *sense)
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 }
Boaz Harroshc1c201202009-02-03 07:47:29 +0100307
308 rq->sense = sense;
309 rq->sense_len = 0;
310
Jens Axboe3d6392c2007-07-09 12:38:05 +0200311 return rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200312out:
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900313 if (rq->cmd != rq->__cmd)
314 kfree(rq->cmd);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200315 blk_put_request(rq);
316 if (next_rq) {
317 blk_rq_unmap_user(next_rq->bio);
318 blk_put_request(next_rq);
319 }
320 return ERR_PTR(ret);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200321}
322
323/*
324 * async completion call-back from the block layer, when scsi/ide/whatever
325 * calls end_that_request_last() on a request
326 */
327static void bsg_rq_end_io(struct request *rq, int uptodate)
328{
329 struct bsg_command *bc = rq->end_io_data;
330 struct bsg_device *bd = bc->bd;
331 unsigned long flags;
332
Jens Axboe5309cb32007-01-23 16:24:41 +0100333 dprintk("%s: finished rq %p bc %p, bio %p stat %d\n",
334 bd->name, rq, bc, bc->bio, uptodate);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200335
336 bc->hdr.duration = jiffies_to_msecs(jiffies - bc->hdr.duration);
337
338 spin_lock_irqsave(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200339 list_move_tail(&bc->list, &bd->done_list);
340 bd->done_cmds++;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200341 spin_unlock_irqrestore(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200342
343 wake_up(&bd->wq_done);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200344}
345
346/*
347 * do final setup of a 'bc' and submit the matching 'rq' to the block
348 * layer for io
349 */
Jens Axboe165125e2007-07-24 09:28:11 +0200350static void bsg_add_command(struct bsg_device *bd, struct request_queue *q,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200351 struct bsg_command *bc, struct request *rq)
352{
Boaz Harrosh05378942009-03-24 12:23:40 +0100353 int at_head = (0 == (bc->hdr.flags & BSG_FLAG_Q_AT_TAIL));
354
Jens Axboe3d6392c2007-07-09 12:38:05 +0200355 /*
356 * add bc command to busy queue and submit rq for io
357 */
358 bc->rq = rq;
359 bc->bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200360 if (rq->next_rq)
361 bc->bidi_bio = rq->next_rq->bio;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200362 bc->hdr.duration = jiffies;
363 spin_lock_irq(&bd->lock);
364 list_add_tail(&bc->list, &bd->busy_list);
365 spin_unlock_irq(&bd->lock);
366
367 dprintk("%s: queueing rq %p, bc %p\n", bd->name, rq, bc);
368
369 rq->end_io_data = bc;
Boaz Harrosh05378942009-03-24 12:23:40 +0100370 blk_execute_rq_nowait(q, NULL, rq, at_head, bsg_rq_end_io);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200371}
372
Jens Axboe25fd1642007-07-17 08:52:29 +0200373static struct bsg_command *bsg_next_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200374{
375 struct bsg_command *bc = NULL;
376
377 spin_lock_irq(&bd->lock);
378 if (bd->done_cmds) {
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900379 bc = list_first_entry(&bd->done_list, struct bsg_command, list);
Jens Axboe25fd1642007-07-17 08:52:29 +0200380 list_del(&bc->list);
381 bd->done_cmds--;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200382 }
383 spin_unlock_irq(&bd->lock);
384
385 return bc;
386}
387
388/*
389 * Get a finished command from the done list
390 */
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200391static struct bsg_command *bsg_get_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200392{
393 struct bsg_command *bc;
394 int ret;
395
396 do {
397 bc = bsg_next_done_cmd(bd);
398 if (bc)
399 break;
400
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200401 if (!test_bit(BSG_F_BLOCK, &bd->flags)) {
402 bc = ERR_PTR(-EAGAIN);
403 break;
404 }
405
406 ret = wait_event_interruptible(bd->wq_done, bd->done_cmds);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200407 if (ret) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200408 bc = ERR_PTR(-ERESTARTSYS);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200409 break;
410 }
411 } while (1);
412
413 dprintk("%s: returning done %p\n", bd->name, bc);
414
415 return bc;
416}
417
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100418static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr,
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200419 struct bio *bio, struct bio *bidi_bio)
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100420{
421 int ret = 0;
422
Boaz Harroshc1c201202009-02-03 07:47:29 +0100423 dprintk("rq %p bio %p 0x%x\n", rq, bio, rq->errors);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100424 /*
425 * fill in all the output members
426 */
427 hdr->device_status = status_byte(rq->errors);
428 hdr->transport_status = host_byte(rq->errors);
429 hdr->driver_status = driver_byte(rq->errors);
430 hdr->info = 0;
431 if (hdr->device_status || hdr->transport_status || hdr->driver_status)
432 hdr->info |= SG_INFO_CHECK;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100433 hdr->response_len = 0;
434
435 if (rq->sense_len && hdr->response) {
Jens Axboe25fd1642007-07-17 08:52:29 +0200436 int len = min_t(unsigned int, hdr->max_response_len,
437 rq->sense_len);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100438
439 ret = copy_to_user((void*)(unsigned long)hdr->response,
440 rq->sense, len);
441 if (!ret)
442 hdr->response_len = len;
443 else
444 ret = -EFAULT;
445 }
446
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200447 if (rq->next_rq) {
Tejun Heoc3a4d782009-05-07 22:24:37 +0900448 hdr->dout_resid = rq->resid_len;
449 hdr->din_resid = rq->next_rq->resid_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200450 blk_rq_unmap_user(bidi_bio);
451 blk_put_request(rq->next_rq);
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900452 } else if (rq_data_dir(rq) == READ)
Tejun Heoc3a4d782009-05-07 22:24:37 +0900453 hdr->din_resid = rq->resid_len;
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900454 else
Tejun Heoc3a4d782009-05-07 22:24:37 +0900455 hdr->dout_resid = rq->resid_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200456
James Bottomley2d507a02007-12-29 10:59:53 -0600457 /*
458 * If the request generated a negative error number, return it
459 * (providing we aren't already returning an error); if it's
460 * just a protocol response (i.e. non negative), that gets
461 * processed above.
462 */
463 if (!ret && rq->errors < 0)
464 ret = rq->errors;
465
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100466 blk_rq_unmap_user(bio);
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900467 if (rq->cmd != rq->__cmd)
468 kfree(rq->cmd);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100469 blk_put_request(rq);
470
471 return ret;
472}
473
Jens Axboe3d6392c2007-07-09 12:38:05 +0200474static int bsg_complete_all_commands(struct bsg_device *bd)
475{
476 struct bsg_command *bc;
477 int ret, tret;
478
479 dprintk("%s: entered\n", bd->name);
480
Jens Axboe3d6392c2007-07-09 12:38:05 +0200481 /*
482 * wait for all commands to complete
483 */
484 ret = 0;
485 do {
Jens Axboe25fd1642007-07-17 08:52:29 +0200486 ret = bsg_io_schedule(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200487 /*
488 * look for -ENODATA specifically -- we'll sometimes get
489 * -ERESTARTSYS when we've taken a signal, but we can't
490 * return until we're done freeing the queue, so ignore
491 * it. The signal will get handled when we're done freeing
492 * the bsg_device.
493 */
494 } while (ret != -ENODATA);
495
496 /*
497 * discard done commands
498 */
499 ret = 0;
500 do {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200501 spin_lock_irq(&bd->lock);
502 if (!bd->queued_cmds) {
503 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200504 break;
505 }
FUJITA Tomonoriefba1a32007-06-07 13:24:06 +0200506 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200507
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200508 bc = bsg_get_done_cmd(bd);
509 if (IS_ERR(bc))
510 break;
511
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200512 tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
513 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200514 if (!ret)
515 ret = tret;
516
517 bsg_free_command(bc);
518 } while (1);
519
520 return ret;
521}
522
Jens Axboe25fd1642007-07-17 08:52:29 +0200523static int
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200524__bsg_read(char __user *buf, size_t count, struct bsg_device *bd,
525 const struct iovec *iov, ssize_t *bytes_read)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200526{
527 struct bsg_command *bc;
528 int nr_commands, ret;
529
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100530 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200531 return -EINVAL;
532
533 ret = 0;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100534 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200535 while (nr_commands) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200536 bc = bsg_get_done_cmd(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200537 if (IS_ERR(bc)) {
538 ret = PTR_ERR(bc);
539 break;
540 }
541
542 /*
543 * this is the only case where we need to copy data back
544 * after completing the request. so do that here,
545 * bsg_complete_work() cannot do that for us
546 */
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200547 ret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
548 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200549
Jens Axboe25fd1642007-07-17 08:52:29 +0200550 if (copy_to_user(buf, &bc->hdr, sizeof(bc->hdr)))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200551 ret = -EFAULT;
552
553 bsg_free_command(bc);
554
555 if (ret)
556 break;
557
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100558 buf += sizeof(struct sg_io_v4);
559 *bytes_read += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200560 nr_commands--;
561 }
562
563 return ret;
564}
565
566static inline void bsg_set_block(struct bsg_device *bd, struct file *file)
567{
568 if (file->f_flags & O_NONBLOCK)
569 clear_bit(BSG_F_BLOCK, &bd->flags);
570 else
571 set_bit(BSG_F_BLOCK, &bd->flags);
572}
573
Jens Axboe25fd1642007-07-17 08:52:29 +0200574/*
575 * Check if the error is a "real" error that we should return.
576 */
Jens Axboe3d6392c2007-07-09 12:38:05 +0200577static inline int err_block_err(int ret)
578{
579 if (ret && ret != -ENOSPC && ret != -ENODATA && ret != -EAGAIN)
580 return 1;
581
582 return 0;
583}
584
585static ssize_t
586bsg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
587{
588 struct bsg_device *bd = file->private_data;
589 int ret;
590 ssize_t bytes_read;
591
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100592 dprintk("%s: read %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200593
594 bsg_set_block(bd, file);
Adel Gadllah0b07de82008-06-26 13:48:27 +0200595
Jens Axboe3d6392c2007-07-09 12:38:05 +0200596 bytes_read = 0;
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200597 ret = __bsg_read(buf, count, bd, NULL, &bytes_read);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200598 *ppos = bytes_read;
599
600 if (!bytes_read || (bytes_read && err_block_err(ret)))
601 bytes_read = ret;
602
603 return bytes_read;
604}
605
Jens Axboe25fd1642007-07-17 08:52:29 +0200606static int __bsg_write(struct bsg_device *bd, const char __user *buf,
Al Viroaeb5d722008-09-02 15:28:45 -0400607 size_t count, ssize_t *bytes_written,
608 fmode_t has_write_perm)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200609{
610 struct bsg_command *bc;
611 struct request *rq;
612 int ret, nr_commands;
613
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100614 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200615 return -EINVAL;
616
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100617 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200618 rq = NULL;
619 bc = NULL;
620 ret = 0;
621 while (nr_commands) {
Jens Axboe165125e2007-07-24 09:28:11 +0200622 struct request_queue *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200623
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200624 bc = bsg_alloc_command(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200625 if (IS_ERR(bc)) {
626 ret = PTR_ERR(bc);
627 bc = NULL;
628 break;
629 }
630
Jens Axboe3d6392c2007-07-09 12:38:05 +0200631 if (copy_from_user(&bc->hdr, buf, sizeof(bc->hdr))) {
632 ret = -EFAULT;
633 break;
634 }
635
636 /*
637 * get a request, fill in the blanks, and add to request queue
638 */
Boaz Harroshc1c201202009-02-03 07:47:29 +0100639 rq = bsg_map_hdr(bd, &bc->hdr, has_write_perm, bc->sense);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200640 if (IS_ERR(rq)) {
641 ret = PTR_ERR(rq);
642 rq = NULL;
643 break;
644 }
645
646 bsg_add_command(bd, q, bc, rq);
647 bc = NULL;
648 rq = NULL;
649 nr_commands--;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100650 buf += sizeof(struct sg_io_v4);
Jens Axboe25fd1642007-07-17 08:52:29 +0200651 *bytes_written += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200652 }
653
Jens Axboe3d6392c2007-07-09 12:38:05 +0200654 if (bc)
655 bsg_free_command(bc);
656
657 return ret;
658}
659
660static ssize_t
661bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
662{
663 struct bsg_device *bd = file->private_data;
Jens Axboe25fd1642007-07-17 08:52:29 +0200664 ssize_t bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200665 int ret;
666
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100667 dprintk("%s: write %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200668
669 bsg_set_block(bd, file);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200670
Jens Axboe25fd1642007-07-17 08:52:29 +0200671 bytes_written = 0;
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900672 ret = __bsg_write(bd, buf, count, &bytes_written,
673 file->f_mode & FMODE_WRITE);
674
Jens Axboe25fd1642007-07-17 08:52:29 +0200675 *ppos = bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200676
677 /*
678 * return bytes written on non-fatal errors
679 */
Jens Axboe25fd1642007-07-17 08:52:29 +0200680 if (!bytes_written || (bytes_written && err_block_err(ret)))
681 bytes_written = ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200682
Jens Axboe25fd1642007-07-17 08:52:29 +0200683 dprintk("%s: returning %Zd\n", bd->name, bytes_written);
684 return bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200685}
686
Jens Axboe3d6392c2007-07-09 12:38:05 +0200687static struct bsg_device *bsg_alloc_device(void)
688{
Jens Axboe3d6392c2007-07-09 12:38:05 +0200689 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200690
691 bd = kzalloc(sizeof(struct bsg_device), GFP_KERNEL);
692 if (unlikely(!bd))
693 return NULL;
694
695 spin_lock_init(&bd->lock);
696
Jens Axboe5309cb32007-01-23 16:24:41 +0100697 bd->max_queue = BSG_DEFAULT_CMDS;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200698
699 INIT_LIST_HEAD(&bd->busy_list);
700 INIT_LIST_HEAD(&bd->done_list);
701 INIT_HLIST_NODE(&bd->dev_list);
702
703 init_waitqueue_head(&bd->wq_free);
704 init_waitqueue_head(&bd->wq_done);
705 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200706}
707
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900708static void bsg_kref_release_function(struct kref *kref)
709{
710 struct bsg_class_device *bcd =
711 container_of(kref, struct bsg_class_device, ref);
James Bottomley8df5fc02008-07-07 15:50:01 -0500712 struct device *parent = bcd->parent;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900713
714 if (bcd->release)
715 bcd->release(bcd->parent);
716
James Bottomley8df5fc02008-07-07 15:50:01 -0500717 put_device(parent);
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900718}
719
Jens Axboe3d6392c2007-07-09 12:38:05 +0200720static int bsg_put_device(struct bsg_device *bd)
721{
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900722 int ret = 0, do_free;
723 struct request_queue *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200724
725 mutex_lock(&bsg_mutex);
726
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900727 do_free = atomic_dec_and_test(&bd->ref_count);
FUJITA Tomonori3f27e3e2008-05-29 07:56:55 +0900728 if (!do_free) {
729 mutex_unlock(&bsg_mutex);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200730 goto out;
FUJITA Tomonori3f27e3e2008-05-29 07:56:55 +0900731 }
732
733 hlist_del(&bd->dev_list);
734 mutex_unlock(&bsg_mutex);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200735
736 dprintk("%s: tearing down\n", bd->name);
737
738 /*
739 * close can always block
740 */
741 set_bit(BSG_F_BLOCK, &bd->flags);
742
743 /*
744 * correct error detection baddies here again. it's the responsibility
745 * of the app to properly reap commands before close() if it wants
746 * fool-proof error detection
747 */
748 ret = bsg_complete_all_commands(bd);
749
Jens Axboe5309cb32007-01-23 16:24:41 +0100750 kfree(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200751out:
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900752 kref_put(&q->bsg_dev.ref, bsg_kref_release_function);
753 if (do_free)
754 blk_put_queue(q);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200755 return ret;
756}
757
758static struct bsg_device *bsg_add_device(struct inode *inode,
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200759 struct request_queue *rq,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200760 struct file *file)
761{
Jens Axboe25fd1642007-07-17 08:52:29 +0200762 struct bsg_device *bd;
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900763 int ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200764#ifdef BSG_DEBUG
765 unsigned char buf[32];
766#endif
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900767 ret = blk_get_queue(rq);
768 if (ret)
769 return ERR_PTR(-ENXIO);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200770
771 bd = bsg_alloc_device();
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900772 if (!bd) {
773 blk_put_queue(rq);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200774 return ERR_PTR(-ENOMEM);
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900775 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200776
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200777 bd->queue = rq;
Adel Gadllah0b07de82008-06-26 13:48:27 +0200778
Jens Axboe3d6392c2007-07-09 12:38:05 +0200779 bsg_set_block(bd, file);
780
781 atomic_set(&bd->ref_count, 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200782 mutex_lock(&bsg_mutex);
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900783 hlist_add_head(&bd->dev_list, bsg_dev_idx_hash(iminor(inode)));
Jens Axboe3d6392c2007-07-09 12:38:05 +0200784
Kay Sievers3ada8b72009-01-06 10:44:43 -0800785 strncpy(bd->name, dev_name(rq->bsg_dev.class_dev), sizeof(bd->name) - 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200786 dprintk("bound to <%s>, max queue %d\n",
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100787 format_dev_t(buf, inode->i_rdev), bd->max_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200788
789 mutex_unlock(&bsg_mutex);
790 return bd;
791}
792
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900793static struct bsg_device *__bsg_get_device(int minor, struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200794{
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900795 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200796 struct hlist_node *entry;
797
798 mutex_lock(&bsg_mutex);
799
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900800 hlist_for_each_entry(bd, entry, bsg_dev_idx_hash(minor), dev_list) {
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900801 if (bd->queue == q) {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200802 atomic_inc(&bd->ref_count);
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900803 goto found;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200804 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200805 }
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900806 bd = NULL;
807found:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200808 mutex_unlock(&bsg_mutex);
809 return bd;
810}
811
812static struct bsg_device *bsg_get_device(struct inode *inode, struct file *file)
813{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900814 struct bsg_device *bd;
815 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200816
Jens Axboe3d6392c2007-07-09 12:38:05 +0200817 /*
818 * find the class device
819 */
Jens Axboe3d6392c2007-07-09 12:38:05 +0200820 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900821 bcd = idr_find(&bsg_minor_idr, iminor(inode));
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900822 if (bcd)
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900823 kref_get(&bcd->ref);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200824 mutex_unlock(&bsg_mutex);
825
826 if (!bcd)
827 return ERR_PTR(-ENODEV);
828
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900829 bd = __bsg_get_device(iminor(inode), bcd->queue);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900830 if (bd)
831 return bd;
832
833 bd = bsg_add_device(inode, bcd->queue, file);
834 if (IS_ERR(bd))
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900835 kref_put(&bcd->ref, bsg_kref_release_function);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900836
837 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200838}
839
840static int bsg_open(struct inode *inode, struct file *file)
841{
Jonathan Corbet75bd2ef2008-05-15 09:09:23 -0600842 struct bsg_device *bd;
843
844 lock_kernel();
845 bd = bsg_get_device(inode, file);
846 unlock_kernel();
Jens Axboe3d6392c2007-07-09 12:38:05 +0200847
848 if (IS_ERR(bd))
849 return PTR_ERR(bd);
850
851 file->private_data = bd;
852 return 0;
853}
854
855static int bsg_release(struct inode *inode, struct file *file)
856{
857 struct bsg_device *bd = file->private_data;
858
859 file->private_data = NULL;
860 return bsg_put_device(bd);
861}
862
863static unsigned int bsg_poll(struct file *file, poll_table *wait)
864{
865 struct bsg_device *bd = file->private_data;
866 unsigned int mask = 0;
867
868 poll_wait(file, &bd->wq_done, wait);
869 poll_wait(file, &bd->wq_free, wait);
870
871 spin_lock_irq(&bd->lock);
872 if (!list_empty(&bd->done_list))
873 mask |= POLLIN | POLLRDNORM;
874 if (bd->queued_cmds >= bd->max_queue)
875 mask |= POLLOUT;
876 spin_unlock_irq(&bd->lock);
877
878 return mask;
879}
880
Jens Axboe25fd1642007-07-17 08:52:29 +0200881static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200882{
883 struct bsg_device *bd = file->private_data;
884 int __user *uarg = (int __user *) arg;
James Bottomley2d507a02007-12-29 10:59:53 -0600885 int ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200886
Jens Axboe3d6392c2007-07-09 12:38:05 +0200887 switch (cmd) {
888 /*
889 * our own ioctls
890 */
891 case SG_GET_COMMAND_Q:
892 return put_user(bd->max_queue, uarg);
Jens Axboe5309cb32007-01-23 16:24:41 +0100893 case SG_SET_COMMAND_Q: {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200894 int queue;
895
896 if (get_user(queue, uarg))
897 return -EFAULT;
Jens Axboe5309cb32007-01-23 16:24:41 +0100898 if (queue < 1)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200899 return -EINVAL;
900
Jens Axboe5309cb32007-01-23 16:24:41 +0100901 spin_lock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200902 bd->max_queue = queue;
Jens Axboe5309cb32007-01-23 16:24:41 +0100903 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200904 return 0;
905 }
906
907 /*
908 * SCSI/sg ioctls
909 */
910 case SG_GET_VERSION_NUM:
911 case SCSI_IOCTL_GET_IDLUN:
912 case SCSI_IOCTL_GET_BUS_NUMBER:
913 case SG_SET_TIMEOUT:
914 case SG_GET_TIMEOUT:
915 case SG_GET_RESERVED_SIZE:
916 case SG_SET_RESERVED_SIZE:
917 case SG_EMULATED_HOST:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200918 case SCSI_IOCTL_SEND_COMMAND: {
919 void __user *uarg = (void __user *) arg;
Al Viro74f3c8a2007-08-27 15:38:10 -0400920 return scsi_cmd_ioctl(bd->queue, NULL, file->f_mode, cmd, uarg);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200921 }
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100922 case SG_IO: {
923 struct request *rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200924 struct bio *bio, *bidi_bio = NULL;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100925 struct sg_io_v4 hdr;
Boaz Harrosh05378942009-03-24 12:23:40 +0100926 int at_head;
Boaz Harroshc1c201202009-02-03 07:47:29 +0100927 u8 sense[SCSI_SENSE_BUFFERSIZE];
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100928
929 if (copy_from_user(&hdr, uarg, sizeof(hdr)))
930 return -EFAULT;
931
Boaz Harroshc1c201202009-02-03 07:47:29 +0100932 rq = bsg_map_hdr(bd, &hdr, file->f_mode & FMODE_WRITE, sense);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100933 if (IS_ERR(rq))
934 return PTR_ERR(rq);
935
936 bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200937 if (rq->next_rq)
938 bidi_bio = rq->next_rq->bio;
Boaz Harrosh05378942009-03-24 12:23:40 +0100939
940 at_head = (0 == (hdr.flags & BSG_FLAG_Q_AT_TAIL));
941 blk_execute_rq(bd->queue, NULL, rq, at_head);
James Bottomley2d507a02007-12-29 10:59:53 -0600942 ret = blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100943
944 if (copy_to_user(uarg, &hdr, sizeof(hdr)))
945 return -EFAULT;
Jens Axboeb711afa2006-12-20 11:25:23 +0100946
James Bottomley2d507a02007-12-29 10:59:53 -0600947 return ret;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100948 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200949 /*
950 * block device ioctls
951 */
952 default:
953#if 0
954 return ioctl_by_bdev(bd->bdev, cmd, arg);
955#else
956 return -ENOTTY;
957#endif
958 }
959}
960
Arjan van de Ven7344be02007-10-15 11:01:53 +0200961static const struct file_operations bsg_fops = {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200962 .read = bsg_read,
963 .write = bsg_write,
964 .poll = bsg_poll,
965 .open = bsg_open,
966 .release = bsg_release,
Jens Axboe25fd1642007-07-17 08:52:29 +0200967 .unlocked_ioctl = bsg_ioctl,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200968 .owner = THIS_MODULE,
969};
970
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200971void bsg_unregister_queue(struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200972{
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200973 struct bsg_class_device *bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200974
FUJITA Tomonoridf468822007-07-21 13:23:25 +0900975 if (!bcd->class_dev)
976 return;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200977
978 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900979 idr_remove(&bsg_minor_idr, bcd->minor);
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200980 sysfs_remove_link(&q->kobj, "bsg");
Tony Jonesee959b02008-02-22 00:13:36 +0100981 device_unregister(bcd->class_dev);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200982 bcd->class_dev = NULL;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900983 kref_put(&bcd->ref, bsg_kref_release_function);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200984 mutex_unlock(&bsg_mutex);
985}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +0200986EXPORT_SYMBOL_GPL(bsg_unregister_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200987
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900988int bsg_register_queue(struct request_queue *q, struct device *parent,
989 const char *name, void (*release)(struct device *))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200990{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900991 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200992 dev_t dev;
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900993 int ret, minor;
Tony Jonesee959b02008-02-22 00:13:36 +0100994 struct device *class_dev = NULL;
James Bottomley39dca552007-07-20 18:22:17 -0500995 const char *devname;
996
997 if (name)
998 devname = name;
999 else
Kay Sievers3ada8b72009-01-06 10:44:43 -08001000 devname = dev_name(parent);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001001
1002 /*
1003 * we need a proper transport to send commands, not a stacked device
1004 */
1005 if (!q->request_fn)
1006 return 0;
1007
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001008 bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001009 memset(bcd, 0, sizeof(*bcd));
Jens Axboe3d6392c2007-07-09 12:38:05 +02001010
1011 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001012
1013 ret = idr_pre_get(&bsg_minor_idr, GFP_KERNEL);
1014 if (!ret) {
1015 ret = -ENOMEM;
1016 goto unlock;
1017 }
1018
1019 ret = idr_get_new(&bsg_minor_idr, bcd, &minor);
1020 if (ret < 0)
1021 goto unlock;
1022
1023 if (minor >= BSG_MAX_DEVS) {
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001024 printk(KERN_ERR "bsg: too many bsg devices\n");
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001025 ret = -EINVAL;
1026 goto remove_idr;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001027 }
1028
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001029 bcd->minor = minor;
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001030 bcd->queue = q;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001031 bcd->parent = get_device(parent);
1032 bcd->release = release;
1033 kref_init(&bcd->ref);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001034 dev = MKDEV(bsg_major, bcd->minor);
Greg Kroah-Hartman1ff9f542008-07-21 20:03:34 -07001035 class_dev = device_create(bsg_class, parent, dev, NULL, "%s", devname);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001036 if (IS_ERR(class_dev)) {
1037 ret = PTR_ERR(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001038 goto put_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001039 }
1040 bcd->class_dev = class_dev;
1041
Linus Torvaldsabce8912007-07-16 11:18:23 -07001042 if (q->kobj.sd) {
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001043 ret = sysfs_create_link(&q->kobj, &bcd->class_dev->kobj, "bsg");
1044 if (ret)
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001045 goto unregister_class_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001046 }
1047
Jens Axboe3d6392c2007-07-09 12:38:05 +02001048 mutex_unlock(&bsg_mutex);
1049 return 0;
James Bottomley6826ee42007-07-20 16:50:10 -05001050
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001051unregister_class_dev:
Tony Jonesee959b02008-02-22 00:13:36 +01001052 device_unregister(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001053put_dev:
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001054 put_device(parent);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001055remove_idr:
1056 idr_remove(&bsg_minor_idr, minor);
1057unlock:
Jens Axboe264a0472007-01-23 16:30:17 +01001058 mutex_unlock(&bsg_mutex);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001059 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001060}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +02001061EXPORT_SYMBOL_GPL(bsg_register_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001062
Greg Kroah-Hartman7e7654a2007-09-12 15:06:57 -07001063static struct cdev bsg_cdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001064
Kay Sievers2bdf9142009-04-30 15:23:42 +02001065static char *bsg_nodename(struct device *dev)
1066{
1067 return kasprintf(GFP_KERNEL, "bsg/%s", dev_name(dev));
1068}
1069
Jens Axboe3d6392c2007-07-09 12:38:05 +02001070static int __init bsg_init(void)
1071{
1072 int ret, i;
Jens Axboe46f6ef42007-07-17 08:56:10 +02001073 dev_t devid;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001074
Jens Axboe5309cb32007-01-23 16:24:41 +01001075 bsg_cmd_cachep = kmem_cache_create("bsg_cmd",
Paul Mundt20c2df82007-07-20 10:11:58 +09001076 sizeof(struct bsg_command), 0, 0, NULL);
Jens Axboe5309cb32007-01-23 16:24:41 +01001077 if (!bsg_cmd_cachep) {
1078 printk(KERN_ERR "bsg: failed creating slab cache\n");
1079 return -ENOMEM;
1080 }
1081
Jens Axboe25fd1642007-07-17 08:52:29 +02001082 for (i = 0; i < BSG_LIST_ARRAY_SIZE; i++)
Jens Axboe3d6392c2007-07-09 12:38:05 +02001083 INIT_HLIST_HEAD(&bsg_device_list[i]);
1084
1085 bsg_class = class_create(THIS_MODULE, "bsg");
Jens Axboe5309cb32007-01-23 16:24:41 +01001086 if (IS_ERR(bsg_class)) {
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001087 ret = PTR_ERR(bsg_class);
1088 goto destroy_kmemcache;
Jens Axboe5309cb32007-01-23 16:24:41 +01001089 }
Kay Sievers2bdf9142009-04-30 15:23:42 +02001090 bsg_class->nodename = bsg_nodename;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001091
Jens Axboe46f6ef42007-07-17 08:56:10 +02001092 ret = alloc_chrdev_region(&devid, 0, BSG_MAX_DEVS, "bsg");
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001093 if (ret)
1094 goto destroy_bsg_class;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001095
Jens Axboe46f6ef42007-07-17 08:56:10 +02001096 bsg_major = MAJOR(devid);
1097
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001098 cdev_init(&bsg_cdev, &bsg_fops);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001099 ret = cdev_add(&bsg_cdev, MKDEV(bsg_major, 0), BSG_MAX_DEVS);
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001100 if (ret)
1101 goto unregister_chrdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001102
Jens Axboe5d3a8cd2007-07-17 15:10:09 +02001103 printk(KERN_INFO BSG_DESCRIPTION " version " BSG_VERSION
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001104 " loaded (major %d)\n", bsg_major);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001105 return 0;
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001106unregister_chrdev:
1107 unregister_chrdev_region(MKDEV(bsg_major, 0), BSG_MAX_DEVS);
1108destroy_bsg_class:
1109 class_destroy(bsg_class);
1110destroy_kmemcache:
1111 kmem_cache_destroy(bsg_cmd_cachep);
1112 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001113}
1114
1115MODULE_AUTHOR("Jens Axboe");
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001116MODULE_DESCRIPTION(BSG_DESCRIPTION);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001117MODULE_LICENSE("GPL");
1118
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001119device_initcall(bsg_init);