blob: 5358f9ae13c1797b7eda131c7033c73a0c525162 [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) {
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;
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 Harroshc1c20122009-02-03 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 Harroshc1c20122009-02-03 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);
FUJITA Tomonoric1d4c412009-06-09 15:17:37 +0200318 next_rq->bio = NULL;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200319 blk_put_request(next_rq);
320 }
321 return ERR_PTR(ret);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200322}
323
324/*
325 * async completion call-back from the block layer, when scsi/ide/whatever
326 * calls end_that_request_last() on a request
327 */
328static void bsg_rq_end_io(struct request *rq, int uptodate)
329{
330 struct bsg_command *bc = rq->end_io_data;
331 struct bsg_device *bd = bc->bd;
332 unsigned long flags;
333
Jens Axboe5309cb32007-01-23 16:24:41 +0100334 dprintk("%s: finished rq %p bc %p, bio %p stat %d\n",
335 bd->name, rq, bc, bc->bio, uptodate);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200336
337 bc->hdr.duration = jiffies_to_msecs(jiffies - bc->hdr.duration);
338
339 spin_lock_irqsave(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200340 list_move_tail(&bc->list, &bd->done_list);
341 bd->done_cmds++;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200342 spin_unlock_irqrestore(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200343
344 wake_up(&bd->wq_done);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200345}
346
347/*
348 * do final setup of a 'bc' and submit the matching 'rq' to the block
349 * layer for io
350 */
Jens Axboe165125e2007-07-24 09:28:11 +0200351static void bsg_add_command(struct bsg_device *bd, struct request_queue *q,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200352 struct bsg_command *bc, struct request *rq)
353{
Boaz Harrosh05378942009-03-24 12:23:40 +0100354 int at_head = (0 == (bc->hdr.flags & BSG_FLAG_Q_AT_TAIL));
355
Jens Axboe3d6392c2007-07-09 12:38:05 +0200356 /*
357 * add bc command to busy queue and submit rq for io
358 */
359 bc->rq = rq;
360 bc->bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200361 if (rq->next_rq)
362 bc->bidi_bio = rq->next_rq->bio;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200363 bc->hdr.duration = jiffies;
364 spin_lock_irq(&bd->lock);
365 list_add_tail(&bc->list, &bd->busy_list);
366 spin_unlock_irq(&bd->lock);
367
368 dprintk("%s: queueing rq %p, bc %p\n", bd->name, rq, bc);
369
370 rq->end_io_data = bc;
Boaz Harrosh05378942009-03-24 12:23:40 +0100371 blk_execute_rq_nowait(q, NULL, rq, at_head, bsg_rq_end_io);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200372}
373
Jens Axboe25fd1642007-07-17 08:52:29 +0200374static struct bsg_command *bsg_next_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200375{
376 struct bsg_command *bc = NULL;
377
378 spin_lock_irq(&bd->lock);
379 if (bd->done_cmds) {
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900380 bc = list_first_entry(&bd->done_list, struct bsg_command, list);
Jens Axboe25fd1642007-07-17 08:52:29 +0200381 list_del(&bc->list);
382 bd->done_cmds--;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200383 }
384 spin_unlock_irq(&bd->lock);
385
386 return bc;
387}
388
389/*
390 * Get a finished command from the done list
391 */
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200392static struct bsg_command *bsg_get_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200393{
394 struct bsg_command *bc;
395 int ret;
396
397 do {
398 bc = bsg_next_done_cmd(bd);
399 if (bc)
400 break;
401
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200402 if (!test_bit(BSG_F_BLOCK, &bd->flags)) {
403 bc = ERR_PTR(-EAGAIN);
404 break;
405 }
406
407 ret = wait_event_interruptible(bd->wq_done, bd->done_cmds);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200408 if (ret) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200409 bc = ERR_PTR(-ERESTARTSYS);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200410 break;
411 }
412 } while (1);
413
414 dprintk("%s: returning done %p\n", bd->name, bc);
415
416 return bc;
417}
418
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100419static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr,
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200420 struct bio *bio, struct bio *bidi_bio)
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100421{
422 int ret = 0;
423
Boaz Harroshc1c20122009-02-03 07:47:29 +0100424 dprintk("rq %p bio %p 0x%x\n", rq, bio, rq->errors);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100425 /*
426 * fill in all the output members
427 */
428 hdr->device_status = status_byte(rq->errors);
429 hdr->transport_status = host_byte(rq->errors);
430 hdr->driver_status = driver_byte(rq->errors);
431 hdr->info = 0;
432 if (hdr->device_status || hdr->transport_status || hdr->driver_status)
433 hdr->info |= SG_INFO_CHECK;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100434 hdr->response_len = 0;
435
436 if (rq->sense_len && hdr->response) {
Jens Axboe25fd1642007-07-17 08:52:29 +0200437 int len = min_t(unsigned int, hdr->max_response_len,
438 rq->sense_len);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100439
440 ret = copy_to_user((void*)(unsigned long)hdr->response,
441 rq->sense, len);
442 if (!ret)
443 hdr->response_len = len;
444 else
445 ret = -EFAULT;
446 }
447
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200448 if (rq->next_rq) {
Tejun Heoc3a4d782009-05-07 22:24:37 +0900449 hdr->dout_resid = rq->resid_len;
450 hdr->din_resid = rq->next_rq->resid_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200451 blk_rq_unmap_user(bidi_bio);
FUJITA Tomonoric1d4c412009-06-09 15:17:37 +0200452 rq->next_rq->bio = NULL;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200453 blk_put_request(rq->next_rq);
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900454 } else if (rq_data_dir(rq) == READ)
Tejun Heoc3a4d782009-05-07 22:24:37 +0900455 hdr->din_resid = rq->resid_len;
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900456 else
Tejun Heoc3a4d782009-05-07 22:24:37 +0900457 hdr->dout_resid = rq->resid_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200458
James Bottomley2d507a02007-12-29 10:59:53 -0600459 /*
460 * If the request generated a negative error number, return it
461 * (providing we aren't already returning an error); if it's
462 * just a protocol response (i.e. non negative), that gets
463 * processed above.
464 */
465 if (!ret && rq->errors < 0)
466 ret = rq->errors;
467
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100468 blk_rq_unmap_user(bio);
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900469 if (rq->cmd != rq->__cmd)
470 kfree(rq->cmd);
FUJITA Tomonoric1d4c412009-06-09 15:17:37 +0200471 rq->bio = NULL;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100472 blk_put_request(rq);
473
474 return ret;
475}
476
Jens Axboe3d6392c2007-07-09 12:38:05 +0200477static int bsg_complete_all_commands(struct bsg_device *bd)
478{
479 struct bsg_command *bc;
480 int ret, tret;
481
482 dprintk("%s: entered\n", bd->name);
483
Jens Axboe3d6392c2007-07-09 12:38:05 +0200484 /*
485 * wait for all commands to complete
486 */
487 ret = 0;
488 do {
Jens Axboe25fd1642007-07-17 08:52:29 +0200489 ret = bsg_io_schedule(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200490 /*
491 * look for -ENODATA specifically -- we'll sometimes get
492 * -ERESTARTSYS when we've taken a signal, but we can't
493 * return until we're done freeing the queue, so ignore
494 * it. The signal will get handled when we're done freeing
495 * the bsg_device.
496 */
497 } while (ret != -ENODATA);
498
499 /*
500 * discard done commands
501 */
502 ret = 0;
503 do {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200504 spin_lock_irq(&bd->lock);
505 if (!bd->queued_cmds) {
506 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200507 break;
508 }
FUJITA Tomonoriefba1a32007-06-07 13:24:06 +0200509 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200510
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200511 bc = bsg_get_done_cmd(bd);
512 if (IS_ERR(bc))
513 break;
514
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200515 tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
516 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200517 if (!ret)
518 ret = tret;
519
520 bsg_free_command(bc);
521 } while (1);
522
523 return ret;
524}
525
Jens Axboe25fd1642007-07-17 08:52:29 +0200526static int
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200527__bsg_read(char __user *buf, size_t count, struct bsg_device *bd,
528 const struct iovec *iov, ssize_t *bytes_read)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200529{
530 struct bsg_command *bc;
531 int nr_commands, ret;
532
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100533 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200534 return -EINVAL;
535
536 ret = 0;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100537 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200538 while (nr_commands) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200539 bc = bsg_get_done_cmd(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200540 if (IS_ERR(bc)) {
541 ret = PTR_ERR(bc);
542 break;
543 }
544
545 /*
546 * this is the only case where we need to copy data back
547 * after completing the request. so do that here,
548 * bsg_complete_work() cannot do that for us
549 */
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200550 ret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
551 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200552
Jens Axboe25fd1642007-07-17 08:52:29 +0200553 if (copy_to_user(buf, &bc->hdr, sizeof(bc->hdr)))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200554 ret = -EFAULT;
555
556 bsg_free_command(bc);
557
558 if (ret)
559 break;
560
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100561 buf += sizeof(struct sg_io_v4);
562 *bytes_read += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200563 nr_commands--;
564 }
565
566 return ret;
567}
568
569static inline void bsg_set_block(struct bsg_device *bd, struct file *file)
570{
571 if (file->f_flags & O_NONBLOCK)
572 clear_bit(BSG_F_BLOCK, &bd->flags);
573 else
574 set_bit(BSG_F_BLOCK, &bd->flags);
575}
576
Jens Axboe25fd1642007-07-17 08:52:29 +0200577/*
578 * Check if the error is a "real" error that we should return.
579 */
Jens Axboe3d6392c2007-07-09 12:38:05 +0200580static inline int err_block_err(int ret)
581{
582 if (ret && ret != -ENOSPC && ret != -ENODATA && ret != -EAGAIN)
583 return 1;
584
585 return 0;
586}
587
588static ssize_t
589bsg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
590{
591 struct bsg_device *bd = file->private_data;
592 int ret;
593 ssize_t bytes_read;
594
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100595 dprintk("%s: read %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200596
597 bsg_set_block(bd, file);
Adel Gadllah0b07de82008-06-26 13:48:27 +0200598
Jens Axboe3d6392c2007-07-09 12:38:05 +0200599 bytes_read = 0;
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200600 ret = __bsg_read(buf, count, bd, NULL, &bytes_read);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200601 *ppos = bytes_read;
602
603 if (!bytes_read || (bytes_read && err_block_err(ret)))
604 bytes_read = ret;
605
606 return bytes_read;
607}
608
Jens Axboe25fd1642007-07-17 08:52:29 +0200609static int __bsg_write(struct bsg_device *bd, const char __user *buf,
Al Viroaeb5d722008-09-02 15:28:45 -0400610 size_t count, ssize_t *bytes_written,
611 fmode_t has_write_perm)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200612{
613 struct bsg_command *bc;
614 struct request *rq;
615 int ret, nr_commands;
616
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100617 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200618 return -EINVAL;
619
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100620 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200621 rq = NULL;
622 bc = NULL;
623 ret = 0;
624 while (nr_commands) {
Jens Axboe165125e2007-07-24 09:28:11 +0200625 struct request_queue *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200626
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200627 bc = bsg_alloc_command(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200628 if (IS_ERR(bc)) {
629 ret = PTR_ERR(bc);
630 bc = NULL;
631 break;
632 }
633
Jens Axboe3d6392c2007-07-09 12:38:05 +0200634 if (copy_from_user(&bc->hdr, buf, sizeof(bc->hdr))) {
635 ret = -EFAULT;
636 break;
637 }
638
639 /*
640 * get a request, fill in the blanks, and add to request queue
641 */
Boaz Harroshc1c20122009-02-03 07:47:29 +0100642 rq = bsg_map_hdr(bd, &bc->hdr, has_write_perm, bc->sense);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200643 if (IS_ERR(rq)) {
644 ret = PTR_ERR(rq);
645 rq = NULL;
646 break;
647 }
648
649 bsg_add_command(bd, q, bc, rq);
650 bc = NULL;
651 rq = NULL;
652 nr_commands--;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100653 buf += sizeof(struct sg_io_v4);
Jens Axboe25fd1642007-07-17 08:52:29 +0200654 *bytes_written += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200655 }
656
Jens Axboe3d6392c2007-07-09 12:38:05 +0200657 if (bc)
658 bsg_free_command(bc);
659
660 return ret;
661}
662
663static ssize_t
664bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
665{
666 struct bsg_device *bd = file->private_data;
Jens Axboe25fd1642007-07-17 08:52:29 +0200667 ssize_t bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200668 int ret;
669
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100670 dprintk("%s: write %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200671
672 bsg_set_block(bd, file);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200673
Jens Axboe25fd1642007-07-17 08:52:29 +0200674 bytes_written = 0;
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900675 ret = __bsg_write(bd, buf, count, &bytes_written,
676 file->f_mode & FMODE_WRITE);
677
Jens Axboe25fd1642007-07-17 08:52:29 +0200678 *ppos = bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200679
680 /*
681 * return bytes written on non-fatal errors
682 */
Jens Axboe25fd1642007-07-17 08:52:29 +0200683 if (!bytes_written || (bytes_written && err_block_err(ret)))
684 bytes_written = ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200685
Jens Axboe25fd1642007-07-17 08:52:29 +0200686 dprintk("%s: returning %Zd\n", bd->name, bytes_written);
687 return bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200688}
689
Jens Axboe3d6392c2007-07-09 12:38:05 +0200690static struct bsg_device *bsg_alloc_device(void)
691{
Jens Axboe3d6392c2007-07-09 12:38:05 +0200692 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200693
694 bd = kzalloc(sizeof(struct bsg_device), GFP_KERNEL);
695 if (unlikely(!bd))
696 return NULL;
697
698 spin_lock_init(&bd->lock);
699
Jens Axboe5309cb32007-01-23 16:24:41 +0100700 bd->max_queue = BSG_DEFAULT_CMDS;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200701
702 INIT_LIST_HEAD(&bd->busy_list);
703 INIT_LIST_HEAD(&bd->done_list);
704 INIT_HLIST_NODE(&bd->dev_list);
705
706 init_waitqueue_head(&bd->wq_free);
707 init_waitqueue_head(&bd->wq_done);
708 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200709}
710
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900711static void bsg_kref_release_function(struct kref *kref)
712{
713 struct bsg_class_device *bcd =
714 container_of(kref, struct bsg_class_device, ref);
James Bottomley8df5fc02008-07-07 15:50:01 -0500715 struct device *parent = bcd->parent;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900716
717 if (bcd->release)
718 bcd->release(bcd->parent);
719
James Bottomley8df5fc02008-07-07 15:50:01 -0500720 put_device(parent);
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900721}
722
Jens Axboe3d6392c2007-07-09 12:38:05 +0200723static int bsg_put_device(struct bsg_device *bd)
724{
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900725 int ret = 0, do_free;
726 struct request_queue *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200727
728 mutex_lock(&bsg_mutex);
729
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900730 do_free = atomic_dec_and_test(&bd->ref_count);
FUJITA Tomonori3f27e3e2008-05-29 07:56:55 +0900731 if (!do_free) {
732 mutex_unlock(&bsg_mutex);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200733 goto out;
FUJITA Tomonori3f27e3e2008-05-29 07:56:55 +0900734 }
735
736 hlist_del(&bd->dev_list);
737 mutex_unlock(&bsg_mutex);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200738
739 dprintk("%s: tearing down\n", bd->name);
740
741 /*
742 * close can always block
743 */
744 set_bit(BSG_F_BLOCK, &bd->flags);
745
746 /*
747 * correct error detection baddies here again. it's the responsibility
748 * of the app to properly reap commands before close() if it wants
749 * fool-proof error detection
750 */
751 ret = bsg_complete_all_commands(bd);
752
Jens Axboe5309cb32007-01-23 16:24:41 +0100753 kfree(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200754out:
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900755 kref_put(&q->bsg_dev.ref, bsg_kref_release_function);
756 if (do_free)
757 blk_put_queue(q);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200758 return ret;
759}
760
761static struct bsg_device *bsg_add_device(struct inode *inode,
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200762 struct request_queue *rq,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200763 struct file *file)
764{
Jens Axboe25fd1642007-07-17 08:52:29 +0200765 struct bsg_device *bd;
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900766 int ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200767#ifdef BSG_DEBUG
768 unsigned char buf[32];
769#endif
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900770 ret = blk_get_queue(rq);
771 if (ret)
772 return ERR_PTR(-ENXIO);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200773
774 bd = bsg_alloc_device();
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900775 if (!bd) {
776 blk_put_queue(rq);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200777 return ERR_PTR(-ENOMEM);
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900778 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200779
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200780 bd->queue = rq;
Adel Gadllah0b07de82008-06-26 13:48:27 +0200781
Jens Axboe3d6392c2007-07-09 12:38:05 +0200782 bsg_set_block(bd, file);
783
784 atomic_set(&bd->ref_count, 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200785 mutex_lock(&bsg_mutex);
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900786 hlist_add_head(&bd->dev_list, bsg_dev_idx_hash(iminor(inode)));
Jens Axboe3d6392c2007-07-09 12:38:05 +0200787
Kay Sievers3ada8b72009-01-06 10:44:43 -0800788 strncpy(bd->name, dev_name(rq->bsg_dev.class_dev), sizeof(bd->name) - 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200789 dprintk("bound to <%s>, max queue %d\n",
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100790 format_dev_t(buf, inode->i_rdev), bd->max_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200791
792 mutex_unlock(&bsg_mutex);
793 return bd;
794}
795
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900796static struct bsg_device *__bsg_get_device(int minor, struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200797{
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900798 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200799 struct hlist_node *entry;
800
801 mutex_lock(&bsg_mutex);
802
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900803 hlist_for_each_entry(bd, entry, bsg_dev_idx_hash(minor), dev_list) {
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900804 if (bd->queue == q) {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200805 atomic_inc(&bd->ref_count);
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900806 goto found;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200807 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200808 }
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900809 bd = NULL;
810found:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200811 mutex_unlock(&bsg_mutex);
812 return bd;
813}
814
815static struct bsg_device *bsg_get_device(struct inode *inode, struct file *file)
816{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900817 struct bsg_device *bd;
818 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200819
Jens Axboe3d6392c2007-07-09 12:38:05 +0200820 /*
821 * find the class device
822 */
Jens Axboe3d6392c2007-07-09 12:38:05 +0200823 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900824 bcd = idr_find(&bsg_minor_idr, iminor(inode));
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900825 if (bcd)
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900826 kref_get(&bcd->ref);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200827 mutex_unlock(&bsg_mutex);
828
829 if (!bcd)
830 return ERR_PTR(-ENODEV);
831
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900832 bd = __bsg_get_device(iminor(inode), bcd->queue);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900833 if (bd)
834 return bd;
835
836 bd = bsg_add_device(inode, bcd->queue, file);
837 if (IS_ERR(bd))
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900838 kref_put(&bcd->ref, bsg_kref_release_function);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900839
840 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200841}
842
843static int bsg_open(struct inode *inode, struct file *file)
844{
Jonathan Corbet75bd2ef2008-05-15 09:09:23 -0600845 struct bsg_device *bd;
846
847 lock_kernel();
848 bd = bsg_get_device(inode, file);
849 unlock_kernel();
Jens Axboe3d6392c2007-07-09 12:38:05 +0200850
851 if (IS_ERR(bd))
852 return PTR_ERR(bd);
853
854 file->private_data = bd;
855 return 0;
856}
857
858static int bsg_release(struct inode *inode, struct file *file)
859{
860 struct bsg_device *bd = file->private_data;
861
862 file->private_data = NULL;
863 return bsg_put_device(bd);
864}
865
866static unsigned int bsg_poll(struct file *file, poll_table *wait)
867{
868 struct bsg_device *bd = file->private_data;
869 unsigned int mask = 0;
870
871 poll_wait(file, &bd->wq_done, wait);
872 poll_wait(file, &bd->wq_free, wait);
873
874 spin_lock_irq(&bd->lock);
875 if (!list_empty(&bd->done_list))
876 mask |= POLLIN | POLLRDNORM;
877 if (bd->queued_cmds >= bd->max_queue)
878 mask |= POLLOUT;
879 spin_unlock_irq(&bd->lock);
880
881 return mask;
882}
883
Jens Axboe25fd1642007-07-17 08:52:29 +0200884static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200885{
886 struct bsg_device *bd = file->private_data;
887 int __user *uarg = (int __user *) arg;
James Bottomley2d507a02007-12-29 10:59:53 -0600888 int ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200889
Jens Axboe3d6392c2007-07-09 12:38:05 +0200890 switch (cmd) {
891 /*
892 * our own ioctls
893 */
894 case SG_GET_COMMAND_Q:
895 return put_user(bd->max_queue, uarg);
Jens Axboe5309cb32007-01-23 16:24:41 +0100896 case SG_SET_COMMAND_Q: {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200897 int queue;
898
899 if (get_user(queue, uarg))
900 return -EFAULT;
Jens Axboe5309cb32007-01-23 16:24:41 +0100901 if (queue < 1)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200902 return -EINVAL;
903
Jens Axboe5309cb32007-01-23 16:24:41 +0100904 spin_lock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200905 bd->max_queue = queue;
Jens Axboe5309cb32007-01-23 16:24:41 +0100906 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200907 return 0;
908 }
909
910 /*
911 * SCSI/sg ioctls
912 */
913 case SG_GET_VERSION_NUM:
914 case SCSI_IOCTL_GET_IDLUN:
915 case SCSI_IOCTL_GET_BUS_NUMBER:
916 case SG_SET_TIMEOUT:
917 case SG_GET_TIMEOUT:
918 case SG_GET_RESERVED_SIZE:
919 case SG_SET_RESERVED_SIZE:
920 case SG_EMULATED_HOST:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200921 case SCSI_IOCTL_SEND_COMMAND: {
922 void __user *uarg = (void __user *) arg;
Al Viro74f3c8a2007-08-27 15:38:10 -0400923 return scsi_cmd_ioctl(bd->queue, NULL, file->f_mode, cmd, uarg);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200924 }
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100925 case SG_IO: {
926 struct request *rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200927 struct bio *bio, *bidi_bio = NULL;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100928 struct sg_io_v4 hdr;
Boaz Harrosh05378942009-03-24 12:23:40 +0100929 int at_head;
Boaz Harroshc1c20122009-02-03 07:47:29 +0100930 u8 sense[SCSI_SENSE_BUFFERSIZE];
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100931
932 if (copy_from_user(&hdr, uarg, sizeof(hdr)))
933 return -EFAULT;
934
Boaz Harroshc1c20122009-02-03 07:47:29 +0100935 rq = bsg_map_hdr(bd, &hdr, file->f_mode & FMODE_WRITE, sense);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100936 if (IS_ERR(rq))
937 return PTR_ERR(rq);
938
939 bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200940 if (rq->next_rq)
941 bidi_bio = rq->next_rq->bio;
Boaz Harrosh05378942009-03-24 12:23:40 +0100942
943 at_head = (0 == (hdr.flags & BSG_FLAG_Q_AT_TAIL));
944 blk_execute_rq(bd->queue, NULL, rq, at_head);
James Bottomley2d507a02007-12-29 10:59:53 -0600945 ret = blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100946
947 if (copy_to_user(uarg, &hdr, sizeof(hdr)))
948 return -EFAULT;
Jens Axboeb711afa2006-12-20 11:25:23 +0100949
James Bottomley2d507a02007-12-29 10:59:53 -0600950 return ret;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100951 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200952 /*
953 * block device ioctls
954 */
955 default:
956#if 0
957 return ioctl_by_bdev(bd->bdev, cmd, arg);
958#else
959 return -ENOTTY;
960#endif
961 }
962}
963
Arjan van de Ven7344be02007-10-15 11:01:53 +0200964static const struct file_operations bsg_fops = {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200965 .read = bsg_read,
966 .write = bsg_write,
967 .poll = bsg_poll,
968 .open = bsg_open,
969 .release = bsg_release,
Jens Axboe25fd1642007-07-17 08:52:29 +0200970 .unlocked_ioctl = bsg_ioctl,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200971 .owner = THIS_MODULE,
972};
973
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200974void bsg_unregister_queue(struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200975{
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200976 struct bsg_class_device *bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200977
FUJITA Tomonoridf468822007-07-21 13:23:25 +0900978 if (!bcd->class_dev)
979 return;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200980
981 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900982 idr_remove(&bsg_minor_idr, bcd->minor);
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200983 sysfs_remove_link(&q->kobj, "bsg");
Tony Jonesee959b02008-02-22 00:13:36 +0100984 device_unregister(bcd->class_dev);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200985 bcd->class_dev = NULL;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900986 kref_put(&bcd->ref, bsg_kref_release_function);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200987 mutex_unlock(&bsg_mutex);
988}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +0200989EXPORT_SYMBOL_GPL(bsg_unregister_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200990
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900991int bsg_register_queue(struct request_queue *q, struct device *parent,
992 const char *name, void (*release)(struct device *))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200993{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900994 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200995 dev_t dev;
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900996 int ret, minor;
Tony Jonesee959b02008-02-22 00:13:36 +0100997 struct device *class_dev = NULL;
James Bottomley39dca552007-07-20 18:22:17 -0500998 const char *devname;
999
1000 if (name)
1001 devname = name;
1002 else
Kay Sievers3ada8b72009-01-06 10:44:43 -08001003 devname = dev_name(parent);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001004
1005 /*
1006 * we need a proper transport to send commands, not a stacked device
1007 */
1008 if (!q->request_fn)
1009 return 0;
1010
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001011 bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001012 memset(bcd, 0, sizeof(*bcd));
Jens Axboe3d6392c2007-07-09 12:38:05 +02001013
1014 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001015
1016 ret = idr_pre_get(&bsg_minor_idr, GFP_KERNEL);
1017 if (!ret) {
1018 ret = -ENOMEM;
1019 goto unlock;
1020 }
1021
1022 ret = idr_get_new(&bsg_minor_idr, bcd, &minor);
1023 if (ret < 0)
1024 goto unlock;
1025
1026 if (minor >= BSG_MAX_DEVS) {
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001027 printk(KERN_ERR "bsg: too many bsg devices\n");
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001028 ret = -EINVAL;
1029 goto remove_idr;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001030 }
1031
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001032 bcd->minor = minor;
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001033 bcd->queue = q;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001034 bcd->parent = get_device(parent);
1035 bcd->release = release;
1036 kref_init(&bcd->ref);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001037 dev = MKDEV(bsg_major, bcd->minor);
Greg Kroah-Hartman1ff9f542008-07-21 20:03:34 -07001038 class_dev = device_create(bsg_class, parent, dev, NULL, "%s", devname);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001039 if (IS_ERR(class_dev)) {
1040 ret = PTR_ERR(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001041 goto put_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001042 }
1043 bcd->class_dev = class_dev;
1044
Linus Torvaldsabce8912007-07-16 11:18:23 -07001045 if (q->kobj.sd) {
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001046 ret = sysfs_create_link(&q->kobj, &bcd->class_dev->kobj, "bsg");
1047 if (ret)
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001048 goto unregister_class_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001049 }
1050
Jens Axboe3d6392c2007-07-09 12:38:05 +02001051 mutex_unlock(&bsg_mutex);
1052 return 0;
James Bottomley6826ee42007-07-20 16:50:10 -05001053
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001054unregister_class_dev:
Tony Jonesee959b02008-02-22 00:13:36 +01001055 device_unregister(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001056put_dev:
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001057 put_device(parent);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001058remove_idr:
1059 idr_remove(&bsg_minor_idr, minor);
1060unlock:
Jens Axboe264a0472007-01-23 16:30:17 +01001061 mutex_unlock(&bsg_mutex);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001062 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001063}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +02001064EXPORT_SYMBOL_GPL(bsg_register_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001065
Greg Kroah-Hartman7e7654a2007-09-12 15:06:57 -07001066static struct cdev bsg_cdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001067
Jens Axboe3d6392c2007-07-09 12:38:05 +02001068static int __init bsg_init(void)
1069{
1070 int ret, i;
Jens Axboe46f6ef42007-07-17 08:56:10 +02001071 dev_t devid;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001072
Jens Axboe5309cb32007-01-23 16:24:41 +01001073 bsg_cmd_cachep = kmem_cache_create("bsg_cmd",
Paul Mundt20c2df82007-07-20 10:11:58 +09001074 sizeof(struct bsg_command), 0, 0, NULL);
Jens Axboe5309cb32007-01-23 16:24:41 +01001075 if (!bsg_cmd_cachep) {
1076 printk(KERN_ERR "bsg: failed creating slab cache\n");
1077 return -ENOMEM;
1078 }
1079
Jens Axboe25fd1642007-07-17 08:52:29 +02001080 for (i = 0; i < BSG_LIST_ARRAY_SIZE; i++)
Jens Axboe3d6392c2007-07-09 12:38:05 +02001081 INIT_HLIST_HEAD(&bsg_device_list[i]);
1082
1083 bsg_class = class_create(THIS_MODULE, "bsg");
Jens Axboe5309cb32007-01-23 16:24:41 +01001084 if (IS_ERR(bsg_class)) {
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001085 ret = PTR_ERR(bsg_class);
1086 goto destroy_kmemcache;
Jens Axboe5309cb32007-01-23 16:24:41 +01001087 }
Jens Axboe3d6392c2007-07-09 12:38:05 +02001088
Jens Axboe46f6ef42007-07-17 08:56:10 +02001089 ret = alloc_chrdev_region(&devid, 0, BSG_MAX_DEVS, "bsg");
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001090 if (ret)
1091 goto destroy_bsg_class;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001092
Jens Axboe46f6ef42007-07-17 08:56:10 +02001093 bsg_major = MAJOR(devid);
1094
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001095 cdev_init(&bsg_cdev, &bsg_fops);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001096 ret = cdev_add(&bsg_cdev, MKDEV(bsg_major, 0), BSG_MAX_DEVS);
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001097 if (ret)
1098 goto unregister_chrdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001099
Jens Axboe5d3a8cd2007-07-17 15:10:09 +02001100 printk(KERN_INFO BSG_DESCRIPTION " version " BSG_VERSION
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001101 " loaded (major %d)\n", bsg_major);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001102 return 0;
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001103unregister_chrdev:
1104 unregister_chrdev_region(MKDEV(bsg_major, 0), BSG_MAX_DEVS);
1105destroy_bsg_class:
1106 class_destroy(bsg_class);
1107destroy_kmemcache:
1108 kmem_cache_destroy(bsg_cmd_cachep);
1109 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001110}
1111
1112MODULE_AUTHOR("Jens Axboe");
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001113MODULE_DESCRIPTION(BSG_DESCRIPTION);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001114MODULE_LICENSE("GPL");
1115
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001116device_initcall(bsg_init);