blob: 7cdec32205d829abe4be66ec7121d203d1547257 [file] [log] [blame]
Jens Axboe3d6392c2007-07-09 12:38:05 +02001/*
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +09002 * bsg.c - block layer implementation of the sg v4 interface
Jens Axboe3d6392c2007-07-09 12:38:05 +02003 *
4 * Copyright (C) 2004 Jens Axboe <axboe@suse.de> SUSE Labs
5 * Copyright (C) 2004 Peter M. Jones <pjones@redhat.com>
6 *
7 * This file is subject to the terms and conditions of the GNU General Public
8 * License version 2. See the file "COPYING" in the main directory of this
9 * archive for more details.
10 *
11 */
Jens Axboe3d6392c2007-07-09 12:38:05 +020012#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/file.h>
15#include <linux/blkdev.h>
16#include <linux/poll.h>
17#include <linux/cdev.h>
18#include <linux/percpu.h>
19#include <linux/uio.h>
FUJITA Tomonori598443a2007-07-23 09:33:26 +090020#include <linux/idr.h>
Jens Axboe3d6392c2007-07-09 12:38:05 +020021#include <linux/bsg.h>
22
23#include <scsi/scsi.h>
24#include <scsi/scsi_ioctl.h>
25#include <scsi/scsi_cmnd.h>
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +020026#include <scsi/scsi_device.h>
27#include <scsi/scsi_driver.h>
Jens Axboe3d6392c2007-07-09 12:38:05 +020028#include <scsi/sg.h>
29
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +020030#define BSG_DESCRIPTION "Block layer SCSI generic (bsg) driver"
31#define BSG_VERSION "0.4"
Jens Axboe3d6392c2007-07-09 12:38:05 +020032
Jens Axboe3d6392c2007-07-09 12:38:05 +020033struct bsg_device {
Jens Axboe165125e2007-07-24 09:28:11 +020034 struct request_queue *queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +020035 spinlock_t lock;
36 struct list_head busy_list;
37 struct list_head done_list;
38 struct hlist_node dev_list;
39 atomic_t ref_count;
Jens Axboe3d6392c2007-07-09 12:38:05 +020040 int queued_cmds;
41 int done_cmds;
Jens Axboe3d6392c2007-07-09 12:38:05 +020042 wait_queue_head_t wq_done;
43 wait_queue_head_t wq_free;
FUJITA Tomonorid351af02007-07-09 12:40:35 +020044 char name[BUS_ID_SIZE];
Jens Axboe3d6392c2007-07-09 12:38:05 +020045 int max_queue;
46 unsigned long flags;
47};
48
49enum {
50 BSG_F_BLOCK = 1,
51 BSG_F_WRITE_PERM = 2,
52};
53
Jens Axboe5309cb32007-01-23 16:24:41 +010054#define BSG_DEFAULT_CMDS 64
FUJITA Tomonori292b7f22007-03-28 13:29:58 +020055#define BSG_MAX_DEVS 32768
Jens Axboe3d6392c2007-07-09 12:38:05 +020056
57#undef BSG_DEBUG
58
59#ifdef BSG_DEBUG
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 Tomonori70e36ec2006-12-20 11:20:15 +0100175 struct sg_io_v4 *hdr, int has_write_perm)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200176{
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900177 if (hdr->request_len > BLK_MAX_CDB) {
178 rq->cmd = kzalloc(hdr->request_len, GFP_KERNEL);
179 if (!rq->cmd)
180 return -ENOMEM;
181 }
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100182
183 if (copy_from_user(rq->cmd, (void *)(unsigned long)hdr->request,
184 hdr->request_len))
185 return -EFAULT;
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200186
187 if (hdr->subprotocol == BSG_SUB_PROTOCOL_SCSI_CMD) {
188 if (blk_verify_command(rq->cmd, has_write_perm))
189 return -EPERM;
190 } else if (!capable(CAP_SYS_RAWIO))
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100191 return -EPERM;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200192
193 /*
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100194 * fill in request structure
Jens Axboe3d6392c2007-07-09 12:38:05 +0200195 */
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100196 rq->cmd_len = hdr->request_len;
197 rq->cmd_type = REQ_TYPE_BLOCK_PC;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200198
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100199 rq->timeout = (hdr->timeout * HZ) / 1000;
200 if (!rq->timeout)
201 rq->timeout = q->sg_timeout;
202 if (!rq->timeout)
203 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200204
205 return 0;
206}
207
208/*
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100209 * Check if sg_io_v4 from user is allowed and valid
210 */
211static int
Jens Axboe165125e2007-07-24 09:28:11 +0200212bsg_validate_sgv4_hdr(struct request_queue *q, struct sg_io_v4 *hdr, int *rw)
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100213{
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200214 int ret = 0;
215
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100216 if (hdr->guard != 'Q')
217 return -EINVAL;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100218 if (hdr->dout_xfer_len > (q->max_sectors << 9) ||
219 hdr->din_xfer_len > (q->max_sectors << 9))
220 return -EIO;
221
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 *
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100244bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200245{
Jens Axboe165125e2007-07-24 09:28:11 +0200246 struct request_queue *q = bd->queue;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200247 struct request *rq, *next_rq = NULL;
Jens Axboe25fd1642007-07-17 08:52:29 +0200248 int ret, rw;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100249 unsigned int dxfer_len;
250 void *dxferp = NULL;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200251
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100252 dprintk("map hdr %llx/%u %llx/%u\n", (unsigned long long) hdr->dout_xferp,
253 hdr->dout_xfer_len, (unsigned long long) hdr->din_xferp,
254 hdr->din_xfer_len);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200255
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100256 ret = bsg_validate_sgv4_hdr(q, hdr, &rw);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200257 if (ret)
258 return ERR_PTR(ret);
259
260 /*
261 * map scatter-gather elements seperately and string them to request
262 */
263 rq = blk_get_request(q, rw, GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200264 if (!rq)
265 return ERR_PTR(-ENOMEM);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100266 ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, test_bit(BSG_F_WRITE_PERM,
267 &bd->flags));
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;
286 ret = blk_rq_map_user(q, next_rq, dxferp, hdr->din_xfer_len);
287 if (ret)
288 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200289 }
290
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100291 if (hdr->dout_xfer_len) {
292 dxfer_len = hdr->dout_xfer_len;
293 dxferp = (void*)(unsigned long)hdr->dout_xferp;
294 } else if (hdr->din_xfer_len) {
295 dxfer_len = hdr->din_xfer_len;
296 dxferp = (void*)(unsigned long)hdr->din_xferp;
297 } else
298 dxfer_len = 0;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200299
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100300 if (dxfer_len) {
301 ret = blk_rq_map_user(q, rq, dxferp, dxfer_len);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200302 if (ret)
303 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200304 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200305 return rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200306out:
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900307 if (rq->cmd != rq->__cmd)
308 kfree(rq->cmd);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200309 blk_put_request(rq);
310 if (next_rq) {
311 blk_rq_unmap_user(next_rq->bio);
312 blk_put_request(next_rq);
313 }
314 return ERR_PTR(ret);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200315}
316
317/*
318 * async completion call-back from the block layer, when scsi/ide/whatever
319 * calls end_that_request_last() on a request
320 */
321static void bsg_rq_end_io(struct request *rq, int uptodate)
322{
323 struct bsg_command *bc = rq->end_io_data;
324 struct bsg_device *bd = bc->bd;
325 unsigned long flags;
326
Jens Axboe5309cb32007-01-23 16:24:41 +0100327 dprintk("%s: finished rq %p bc %p, bio %p stat %d\n",
328 bd->name, rq, bc, bc->bio, uptodate);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200329
330 bc->hdr.duration = jiffies_to_msecs(jiffies - bc->hdr.duration);
331
332 spin_lock_irqsave(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200333 list_move_tail(&bc->list, &bd->done_list);
334 bd->done_cmds++;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200335 spin_unlock_irqrestore(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200336
337 wake_up(&bd->wq_done);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200338}
339
340/*
341 * do final setup of a 'bc' and submit the matching 'rq' to the block
342 * layer for io
343 */
Jens Axboe165125e2007-07-24 09:28:11 +0200344static void bsg_add_command(struct bsg_device *bd, struct request_queue *q,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200345 struct bsg_command *bc, struct request *rq)
346{
347 rq->sense = bc->sense;
348 rq->sense_len = 0;
349
350 /*
351 * add bc command to busy queue and submit rq for io
352 */
353 bc->rq = rq;
354 bc->bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200355 if (rq->next_rq)
356 bc->bidi_bio = rq->next_rq->bio;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200357 bc->hdr.duration = jiffies;
358 spin_lock_irq(&bd->lock);
359 list_add_tail(&bc->list, &bd->busy_list);
360 spin_unlock_irq(&bd->lock);
361
362 dprintk("%s: queueing rq %p, bc %p\n", bd->name, rq, bc);
363
364 rq->end_io_data = bc;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200365 blk_execute_rq_nowait(q, NULL, rq, 1, bsg_rq_end_io);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200366}
367
Jens Axboe25fd1642007-07-17 08:52:29 +0200368static struct bsg_command *bsg_next_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200369{
370 struct bsg_command *bc = NULL;
371
372 spin_lock_irq(&bd->lock);
373 if (bd->done_cmds) {
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900374 bc = list_first_entry(&bd->done_list, struct bsg_command, list);
Jens Axboe25fd1642007-07-17 08:52:29 +0200375 list_del(&bc->list);
376 bd->done_cmds--;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200377 }
378 spin_unlock_irq(&bd->lock);
379
380 return bc;
381}
382
383/*
384 * Get a finished command from the done list
385 */
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200386static struct bsg_command *bsg_get_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200387{
388 struct bsg_command *bc;
389 int ret;
390
391 do {
392 bc = bsg_next_done_cmd(bd);
393 if (bc)
394 break;
395
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200396 if (!test_bit(BSG_F_BLOCK, &bd->flags)) {
397 bc = ERR_PTR(-EAGAIN);
398 break;
399 }
400
401 ret = wait_event_interruptible(bd->wq_done, bd->done_cmds);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200402 if (ret) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200403 bc = ERR_PTR(-ERESTARTSYS);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200404 break;
405 }
406 } while (1);
407
408 dprintk("%s: returning done %p\n", bd->name, bc);
409
410 return bc;
411}
412
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100413static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr,
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200414 struct bio *bio, struct bio *bidi_bio)
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100415{
416 int ret = 0;
417
418 dprintk("rq %p bio %p %u\n", rq, bio, rq->errors);
419 /*
420 * fill in all the output members
421 */
422 hdr->device_status = status_byte(rq->errors);
423 hdr->transport_status = host_byte(rq->errors);
424 hdr->driver_status = driver_byte(rq->errors);
425 hdr->info = 0;
426 if (hdr->device_status || hdr->transport_status || hdr->driver_status)
427 hdr->info |= SG_INFO_CHECK;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100428 hdr->response_len = 0;
429
430 if (rq->sense_len && hdr->response) {
Jens Axboe25fd1642007-07-17 08:52:29 +0200431 int len = min_t(unsigned int, hdr->max_response_len,
432 rq->sense_len);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100433
434 ret = copy_to_user((void*)(unsigned long)hdr->response,
435 rq->sense, len);
436 if (!ret)
437 hdr->response_len = len;
438 else
439 ret = -EFAULT;
440 }
441
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200442 if (rq->next_rq) {
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100443 hdr->dout_resid = rq->data_len;
444 hdr->din_resid = rq->next_rq->data_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200445 blk_rq_unmap_user(bidi_bio);
446 blk_put_request(rq->next_rq);
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900447 } else if (rq_data_dir(rq) == READ)
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100448 hdr->din_resid = rq->data_len;
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900449 else
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100450 hdr->dout_resid = rq->data_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200451
James Bottomley2d507a02007-12-29 10:59:53 -0600452 /*
453 * If the request generated a negative error number, return it
454 * (providing we aren't already returning an error); if it's
455 * just a protocol response (i.e. non negative), that gets
456 * processed above.
457 */
458 if (!ret && rq->errors < 0)
459 ret = rq->errors;
460
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100461 blk_rq_unmap_user(bio);
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900462 if (rq->cmd != rq->__cmd)
463 kfree(rq->cmd);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100464 blk_put_request(rq);
465
466 return ret;
467}
468
Jens Axboe3d6392c2007-07-09 12:38:05 +0200469static int bsg_complete_all_commands(struct bsg_device *bd)
470{
471 struct bsg_command *bc;
472 int ret, tret;
473
474 dprintk("%s: entered\n", bd->name);
475
Jens Axboe3d6392c2007-07-09 12:38:05 +0200476 /*
477 * wait for all commands to complete
478 */
479 ret = 0;
480 do {
Jens Axboe25fd1642007-07-17 08:52:29 +0200481 ret = bsg_io_schedule(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200482 /*
483 * look for -ENODATA specifically -- we'll sometimes get
484 * -ERESTARTSYS when we've taken a signal, but we can't
485 * return until we're done freeing the queue, so ignore
486 * it. The signal will get handled when we're done freeing
487 * the bsg_device.
488 */
489 } while (ret != -ENODATA);
490
491 /*
492 * discard done commands
493 */
494 ret = 0;
495 do {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200496 spin_lock_irq(&bd->lock);
497 if (!bd->queued_cmds) {
498 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200499 break;
500 }
FUJITA Tomonoriefba1a32007-06-07 13:24:06 +0200501 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200502
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200503 bc = bsg_get_done_cmd(bd);
504 if (IS_ERR(bc))
505 break;
506
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200507 tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
508 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200509 if (!ret)
510 ret = tret;
511
512 bsg_free_command(bc);
513 } while (1);
514
515 return ret;
516}
517
Jens Axboe25fd1642007-07-17 08:52:29 +0200518static int
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200519__bsg_read(char __user *buf, size_t count, struct bsg_device *bd,
520 const struct iovec *iov, ssize_t *bytes_read)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200521{
522 struct bsg_command *bc;
523 int nr_commands, ret;
524
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100525 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200526 return -EINVAL;
527
528 ret = 0;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100529 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200530 while (nr_commands) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200531 bc = bsg_get_done_cmd(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200532 if (IS_ERR(bc)) {
533 ret = PTR_ERR(bc);
534 break;
535 }
536
537 /*
538 * this is the only case where we need to copy data back
539 * after completing the request. so do that here,
540 * bsg_complete_work() cannot do that for us
541 */
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200542 ret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
543 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200544
Jens Axboe25fd1642007-07-17 08:52:29 +0200545 if (copy_to_user(buf, &bc->hdr, sizeof(bc->hdr)))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200546 ret = -EFAULT;
547
548 bsg_free_command(bc);
549
550 if (ret)
551 break;
552
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100553 buf += sizeof(struct sg_io_v4);
554 *bytes_read += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200555 nr_commands--;
556 }
557
558 return ret;
559}
560
561static inline void bsg_set_block(struct bsg_device *bd, struct file *file)
562{
563 if (file->f_flags & O_NONBLOCK)
564 clear_bit(BSG_F_BLOCK, &bd->flags);
565 else
566 set_bit(BSG_F_BLOCK, &bd->flags);
567}
568
569static inline void bsg_set_write_perm(struct bsg_device *bd, struct file *file)
570{
571 if (file->f_mode & FMODE_WRITE)
572 set_bit(BSG_F_WRITE_PERM, &bd->flags);
573 else
574 clear_bit(BSG_F_WRITE_PERM, &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);
598 bytes_read = 0;
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200599 ret = __bsg_read(buf, count, bd, NULL, &bytes_read);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200600 *ppos = bytes_read;
601
602 if (!bytes_read || (bytes_read && err_block_err(ret)))
603 bytes_read = ret;
604
605 return bytes_read;
606}
607
Jens Axboe25fd1642007-07-17 08:52:29 +0200608static int __bsg_write(struct bsg_device *bd, const char __user *buf,
609 size_t count, ssize_t *bytes_written)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200610{
611 struct bsg_command *bc;
612 struct request *rq;
613 int ret, nr_commands;
614
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100615 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200616 return -EINVAL;
617
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100618 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200619 rq = NULL;
620 bc = NULL;
621 ret = 0;
622 while (nr_commands) {
Jens Axboe165125e2007-07-24 09:28:11 +0200623 struct request_queue *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200624
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200625 bc = bsg_alloc_command(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200626 if (IS_ERR(bc)) {
627 ret = PTR_ERR(bc);
628 bc = NULL;
629 break;
630 }
631
Jens Axboe3d6392c2007-07-09 12:38:05 +0200632 if (copy_from_user(&bc->hdr, buf, sizeof(bc->hdr))) {
633 ret = -EFAULT;
634 break;
635 }
636
637 /*
638 * get a request, fill in the blanks, and add to request queue
639 */
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100640 rq = bsg_map_hdr(bd, &bc->hdr);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200641 if (IS_ERR(rq)) {
642 ret = PTR_ERR(rq);
643 rq = NULL;
644 break;
645 }
646
647 bsg_add_command(bd, q, bc, rq);
648 bc = NULL;
649 rq = NULL;
650 nr_commands--;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100651 buf += sizeof(struct sg_io_v4);
Jens Axboe25fd1642007-07-17 08:52:29 +0200652 *bytes_written += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200653 }
654
Jens Axboe3d6392c2007-07-09 12:38:05 +0200655 if (bc)
656 bsg_free_command(bc);
657
658 return ret;
659}
660
661static ssize_t
662bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
663{
664 struct bsg_device *bd = file->private_data;
Jens Axboe25fd1642007-07-17 08:52:29 +0200665 ssize_t bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200666 int ret;
667
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100668 dprintk("%s: write %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200669
670 bsg_set_block(bd, file);
671 bsg_set_write_perm(bd, file);
672
Jens Axboe25fd1642007-07-17 08:52:29 +0200673 bytes_written = 0;
674 ret = __bsg_write(bd, buf, count, &bytes_written);
675 *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);
712
713 if (bcd->release)
714 bcd->release(bcd->parent);
715
716 put_device(bcd->parent);
717}
718
Jens Axboe3d6392c2007-07-09 12:38:05 +0200719static int bsg_put_device(struct bsg_device *bd)
720{
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900721 int ret = 0, do_free;
722 struct request_queue *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200723
724 mutex_lock(&bsg_mutex);
725
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900726 do_free = atomic_dec_and_test(&bd->ref_count);
FUJITA Tomonori3f27e3e2008-05-29 07:56:55 +0900727 if (!do_free) {
728 mutex_unlock(&bsg_mutex);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200729 goto out;
FUJITA Tomonori3f27e3e2008-05-29 07:56:55 +0900730 }
731
732 hlist_del(&bd->dev_list);
733 mutex_unlock(&bsg_mutex);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200734
735 dprintk("%s: tearing down\n", bd->name);
736
737 /*
738 * close can always block
739 */
740 set_bit(BSG_F_BLOCK, &bd->flags);
741
742 /*
743 * correct error detection baddies here again. it's the responsibility
744 * of the app to properly reap commands before close() if it wants
745 * fool-proof error detection
746 */
747 ret = bsg_complete_all_commands(bd);
748
Jens Axboe5309cb32007-01-23 16:24:41 +0100749 kfree(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200750out:
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900751 kref_put(&q->bsg_dev.ref, bsg_kref_release_function);
752 if (do_free)
753 blk_put_queue(q);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200754 return ret;
755}
756
757static struct bsg_device *bsg_add_device(struct inode *inode,
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200758 struct request_queue *rq,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200759 struct file *file)
760{
Jens Axboe25fd1642007-07-17 08:52:29 +0200761 struct bsg_device *bd;
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900762 int ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200763#ifdef BSG_DEBUG
764 unsigned char buf[32];
765#endif
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900766 ret = blk_get_queue(rq);
767 if (ret)
768 return ERR_PTR(-ENXIO);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200769
770 bd = bsg_alloc_device();
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900771 if (!bd) {
772 blk_put_queue(rq);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200773 return ERR_PTR(-ENOMEM);
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900774 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200775
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200776 bd->queue = rq;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200777 bsg_set_block(bd, file);
778
779 atomic_set(&bd->ref_count, 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200780 mutex_lock(&bsg_mutex);
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900781 hlist_add_head(&bd->dev_list, bsg_dev_idx_hash(iminor(inode)));
Jens Axboe3d6392c2007-07-09 12:38:05 +0200782
Tony Jonesee959b02008-02-22 00:13:36 +0100783 strncpy(bd->name, rq->bsg_dev.class_dev->bus_id, sizeof(bd->name) - 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200784 dprintk("bound to <%s>, max queue %d\n",
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100785 format_dev_t(buf, inode->i_rdev), bd->max_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200786
787 mutex_unlock(&bsg_mutex);
788 return bd;
789}
790
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900791static struct bsg_device *__bsg_get_device(int minor, struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200792{
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900793 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200794 struct hlist_node *entry;
795
796 mutex_lock(&bsg_mutex);
797
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900798 hlist_for_each_entry(bd, entry, bsg_dev_idx_hash(minor), dev_list) {
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900799 if (bd->queue == q) {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200800 atomic_inc(&bd->ref_count);
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900801 goto found;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200802 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200803 }
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900804 bd = NULL;
805found:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200806 mutex_unlock(&bsg_mutex);
807 return bd;
808}
809
810static struct bsg_device *bsg_get_device(struct inode *inode, struct file *file)
811{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900812 struct bsg_device *bd;
813 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200814
Jens Axboe3d6392c2007-07-09 12:38:05 +0200815 /*
816 * find the class device
817 */
Jens Axboe3d6392c2007-07-09 12:38:05 +0200818 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900819 bcd = idr_find(&bsg_minor_idr, iminor(inode));
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900820 if (bcd)
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900821 kref_get(&bcd->ref);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200822 mutex_unlock(&bsg_mutex);
823
824 if (!bcd)
825 return ERR_PTR(-ENODEV);
826
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900827 bd = __bsg_get_device(iminor(inode), bcd->queue);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900828 if (bd)
829 return bd;
830
831 bd = bsg_add_device(inode, bcd->queue, file);
832 if (IS_ERR(bd))
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900833 kref_put(&bcd->ref, bsg_kref_release_function);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900834
835 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200836}
837
838static int bsg_open(struct inode *inode, struct file *file)
839{
840 struct bsg_device *bd = bsg_get_device(inode, file);
841
842 if (IS_ERR(bd))
843 return PTR_ERR(bd);
844
845 file->private_data = bd;
846 return 0;
847}
848
849static int bsg_release(struct inode *inode, struct file *file)
850{
851 struct bsg_device *bd = file->private_data;
852
853 file->private_data = NULL;
854 return bsg_put_device(bd);
855}
856
857static unsigned int bsg_poll(struct file *file, poll_table *wait)
858{
859 struct bsg_device *bd = file->private_data;
860 unsigned int mask = 0;
861
862 poll_wait(file, &bd->wq_done, wait);
863 poll_wait(file, &bd->wq_free, wait);
864
865 spin_lock_irq(&bd->lock);
866 if (!list_empty(&bd->done_list))
867 mask |= POLLIN | POLLRDNORM;
868 if (bd->queued_cmds >= bd->max_queue)
869 mask |= POLLOUT;
870 spin_unlock_irq(&bd->lock);
871
872 return mask;
873}
874
Jens Axboe25fd1642007-07-17 08:52:29 +0200875static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200876{
877 struct bsg_device *bd = file->private_data;
878 int __user *uarg = (int __user *) arg;
James Bottomley2d507a02007-12-29 10:59:53 -0600879 int ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200880
Jens Axboe3d6392c2007-07-09 12:38:05 +0200881 switch (cmd) {
882 /*
883 * our own ioctls
884 */
885 case SG_GET_COMMAND_Q:
886 return put_user(bd->max_queue, uarg);
Jens Axboe5309cb32007-01-23 16:24:41 +0100887 case SG_SET_COMMAND_Q: {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200888 int queue;
889
890 if (get_user(queue, uarg))
891 return -EFAULT;
Jens Axboe5309cb32007-01-23 16:24:41 +0100892 if (queue < 1)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200893 return -EINVAL;
894
Jens Axboe5309cb32007-01-23 16:24:41 +0100895 spin_lock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200896 bd->max_queue = queue;
Jens Axboe5309cb32007-01-23 16:24:41 +0100897 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200898 return 0;
899 }
900
901 /*
902 * SCSI/sg ioctls
903 */
904 case SG_GET_VERSION_NUM:
905 case SCSI_IOCTL_GET_IDLUN:
906 case SCSI_IOCTL_GET_BUS_NUMBER:
907 case SG_SET_TIMEOUT:
908 case SG_GET_TIMEOUT:
909 case SG_GET_RESERVED_SIZE:
910 case SG_SET_RESERVED_SIZE:
911 case SG_EMULATED_HOST:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200912 case SCSI_IOCTL_SEND_COMMAND: {
913 void __user *uarg = (void __user *) arg;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200914 return scsi_cmd_ioctl(file, bd->queue, NULL, cmd, uarg);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200915 }
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100916 case SG_IO: {
917 struct request *rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200918 struct bio *bio, *bidi_bio = NULL;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100919 struct sg_io_v4 hdr;
920
921 if (copy_from_user(&hdr, uarg, sizeof(hdr)))
922 return -EFAULT;
923
924 rq = bsg_map_hdr(bd, &hdr);
925 if (IS_ERR(rq))
926 return PTR_ERR(rq);
927
928 bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200929 if (rq->next_rq)
930 bidi_bio = rq->next_rq->bio;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200931 blk_execute_rq(bd->queue, NULL, rq, 0);
James Bottomley2d507a02007-12-29 10:59:53 -0600932 ret = blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100933
934 if (copy_to_user(uarg, &hdr, sizeof(hdr)))
935 return -EFAULT;
Jens Axboeb711afa2006-12-20 11:25:23 +0100936
James Bottomley2d507a02007-12-29 10:59:53 -0600937 return ret;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100938 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200939 /*
940 * block device ioctls
941 */
942 default:
943#if 0
944 return ioctl_by_bdev(bd->bdev, cmd, arg);
945#else
946 return -ENOTTY;
947#endif
948 }
949}
950
Arjan van de Ven7344be02007-10-15 11:01:53 +0200951static const struct file_operations bsg_fops = {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200952 .read = bsg_read,
953 .write = bsg_write,
954 .poll = bsg_poll,
955 .open = bsg_open,
956 .release = bsg_release,
Jens Axboe25fd1642007-07-17 08:52:29 +0200957 .unlocked_ioctl = bsg_ioctl,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200958 .owner = THIS_MODULE,
959};
960
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200961void bsg_unregister_queue(struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200962{
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200963 struct bsg_class_device *bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200964
FUJITA Tomonoridf468822007-07-21 13:23:25 +0900965 if (!bcd->class_dev)
966 return;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200967
968 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900969 idr_remove(&bsg_minor_idr, bcd->minor);
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200970 sysfs_remove_link(&q->kobj, "bsg");
Tony Jonesee959b02008-02-22 00:13:36 +0100971 device_unregister(bcd->class_dev);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200972 bcd->class_dev = NULL;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900973 kref_put(&bcd->ref, bsg_kref_release_function);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200974 mutex_unlock(&bsg_mutex);
975}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +0200976EXPORT_SYMBOL_GPL(bsg_unregister_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200977
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900978int bsg_register_queue(struct request_queue *q, struct device *parent,
979 const char *name, void (*release)(struct device *))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200980{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900981 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200982 dev_t dev;
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900983 int ret, minor;
Tony Jonesee959b02008-02-22 00:13:36 +0100984 struct device *class_dev = NULL;
James Bottomley39dca552007-07-20 18:22:17 -0500985 const char *devname;
986
987 if (name)
988 devname = name;
989 else
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900990 devname = parent->bus_id;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200991
992 /*
993 * we need a proper transport to send commands, not a stacked device
994 */
995 if (!q->request_fn)
996 return 0;
997
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200998 bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200999 memset(bcd, 0, sizeof(*bcd));
Jens Axboe3d6392c2007-07-09 12:38:05 +02001000
1001 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001002
1003 ret = idr_pre_get(&bsg_minor_idr, GFP_KERNEL);
1004 if (!ret) {
1005 ret = -ENOMEM;
1006 goto unlock;
1007 }
1008
1009 ret = idr_get_new(&bsg_minor_idr, bcd, &minor);
1010 if (ret < 0)
1011 goto unlock;
1012
1013 if (minor >= BSG_MAX_DEVS) {
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001014 printk(KERN_ERR "bsg: too many bsg devices\n");
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001015 ret = -EINVAL;
1016 goto remove_idr;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001017 }
1018
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001019 bcd->minor = minor;
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001020 bcd->queue = q;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001021 bcd->parent = get_device(parent);
1022 bcd->release = release;
1023 kref_init(&bcd->ref);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001024 dev = MKDEV(bsg_major, bcd->minor);
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001025 class_dev = device_create(bsg_class, parent, dev, "%s", devname);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001026 if (IS_ERR(class_dev)) {
1027 ret = PTR_ERR(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001028 goto put_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001029 }
1030 bcd->class_dev = class_dev;
1031
Linus Torvaldsabce8912007-07-16 11:18:23 -07001032 if (q->kobj.sd) {
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001033 ret = sysfs_create_link(&q->kobj, &bcd->class_dev->kobj, "bsg");
1034 if (ret)
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001035 goto unregister_class_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001036 }
1037
Jens Axboe3d6392c2007-07-09 12:38:05 +02001038 mutex_unlock(&bsg_mutex);
1039 return 0;
James Bottomley6826ee42007-07-20 16:50:10 -05001040
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001041unregister_class_dev:
Tony Jonesee959b02008-02-22 00:13:36 +01001042 device_unregister(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001043put_dev:
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001044 put_device(parent);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001045remove_idr:
1046 idr_remove(&bsg_minor_idr, minor);
1047unlock:
Jens Axboe264a0472007-01-23 16:30:17 +01001048 mutex_unlock(&bsg_mutex);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001049 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001050}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +02001051EXPORT_SYMBOL_GPL(bsg_register_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001052
Greg Kroah-Hartman7e7654a2007-09-12 15:06:57 -07001053static struct cdev bsg_cdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001054
Jens Axboe3d6392c2007-07-09 12:38:05 +02001055static int __init bsg_init(void)
1056{
1057 int ret, i;
Jens Axboe46f6ef42007-07-17 08:56:10 +02001058 dev_t devid;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001059
Jens Axboe5309cb32007-01-23 16:24:41 +01001060 bsg_cmd_cachep = kmem_cache_create("bsg_cmd",
Paul Mundt20c2df82007-07-20 10:11:58 +09001061 sizeof(struct bsg_command), 0, 0, NULL);
Jens Axboe5309cb32007-01-23 16:24:41 +01001062 if (!bsg_cmd_cachep) {
1063 printk(KERN_ERR "bsg: failed creating slab cache\n");
1064 return -ENOMEM;
1065 }
1066
Jens Axboe25fd1642007-07-17 08:52:29 +02001067 for (i = 0; i < BSG_LIST_ARRAY_SIZE; i++)
Jens Axboe3d6392c2007-07-09 12:38:05 +02001068 INIT_HLIST_HEAD(&bsg_device_list[i]);
1069
1070 bsg_class = class_create(THIS_MODULE, "bsg");
Jens Axboe5309cb32007-01-23 16:24:41 +01001071 if (IS_ERR(bsg_class)) {
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001072 ret = PTR_ERR(bsg_class);
1073 goto destroy_kmemcache;
Jens Axboe5309cb32007-01-23 16:24:41 +01001074 }
Jens Axboe3d6392c2007-07-09 12:38:05 +02001075
Jens Axboe46f6ef42007-07-17 08:56:10 +02001076 ret = alloc_chrdev_region(&devid, 0, BSG_MAX_DEVS, "bsg");
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001077 if (ret)
1078 goto destroy_bsg_class;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001079
Jens Axboe46f6ef42007-07-17 08:56:10 +02001080 bsg_major = MAJOR(devid);
1081
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001082 cdev_init(&bsg_cdev, &bsg_fops);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001083 ret = cdev_add(&bsg_cdev, MKDEV(bsg_major, 0), BSG_MAX_DEVS);
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001084 if (ret)
1085 goto unregister_chrdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001086
Jens Axboe5d3a8cd2007-07-17 15:10:09 +02001087 printk(KERN_INFO BSG_DESCRIPTION " version " BSG_VERSION
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001088 " loaded (major %d)\n", bsg_major);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001089 return 0;
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001090unregister_chrdev:
1091 unregister_chrdev_region(MKDEV(bsg_major, 0), BSG_MAX_DEVS);
1092destroy_bsg_class:
1093 class_destroy(bsg_class);
1094destroy_kmemcache:
1095 kmem_cache_destroy(bsg_cmd_cachep);
1096 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001097}
1098
1099MODULE_AUTHOR("Jens Axboe");
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001100MODULE_DESCRIPTION(BSG_DESCRIPTION);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001101MODULE_LICENSE("GPL");
1102
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001103device_initcall(bsg_init);