blob: e73e50daf3d0a36df8977cad29b550e3139fbef0 [file] [log] [blame]
Jens Axboe3d6392c2007-07-09 12:38:05 +02001/*
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +09002 * bsg.c - block layer implementation of the sg v4 interface
Jens Axboe3d6392c2007-07-09 12:38:05 +02003 *
4 * Copyright (C) 2004 Jens Axboe <axboe@suse.de> SUSE Labs
5 * Copyright (C) 2004 Peter M. Jones <pjones@redhat.com>
6 *
7 * This file is subject to the terms and conditions of the GNU General Public
8 * License version 2. See the file "COPYING" in the main directory of this
9 * archive for more details.
10 *
11 */
Jens Axboe3d6392c2007-07-09 12:38:05 +020012#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/file.h>
15#include <linux/blkdev.h>
16#include <linux/poll.h>
17#include <linux/cdev.h>
18#include <linux/percpu.h>
19#include <linux/uio.h>
FUJITA Tomonori598443a2007-07-23 09:33:26 +090020#include <linux/idr.h>
Jens Axboe3d6392c2007-07-09 12:38:05 +020021#include <linux/bsg.h>
Jonathan Corbet75bd2ef2008-05-15 09:09:23 -060022#include <linux/smp_lock.h>
Jens Axboe3d6392c2007-07-09 12:38:05 +020023
24#include <scsi/scsi.h>
25#include <scsi/scsi_ioctl.h>
26#include <scsi/scsi_cmnd.h>
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +020027#include <scsi/scsi_device.h>
28#include <scsi/scsi_driver.h>
Jens Axboe3d6392c2007-07-09 12:38:05 +020029#include <scsi/sg.h>
30
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +020031#define BSG_DESCRIPTION "Block layer SCSI generic (bsg) driver"
32#define BSG_VERSION "0.4"
Jens Axboe3d6392c2007-07-09 12:38:05 +020033
Jens Axboe3d6392c2007-07-09 12:38:05 +020034struct bsg_device {
Jens Axboe165125e2007-07-24 09:28:11 +020035 struct request_queue *queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +020036 spinlock_t lock;
37 struct list_head busy_list;
38 struct list_head done_list;
39 struct hlist_node dev_list;
40 atomic_t ref_count;
Jens Axboe3d6392c2007-07-09 12:38:05 +020041 int queued_cmds;
42 int done_cmds;
Jens Axboe3d6392c2007-07-09 12:38:05 +020043 wait_queue_head_t wq_done;
44 wait_queue_head_t wq_free;
FUJITA Tomonorid351af02007-07-09 12:40:35 +020045 char name[BUS_ID_SIZE];
Jens Axboe3d6392c2007-07-09 12:38:05 +020046 int max_queue;
47 unsigned long flags;
48};
49
50enum {
51 BSG_F_BLOCK = 1,
Jens Axboe3d6392c2007-07-09 12:38:05 +020052};
53
Jens Axboe5309cb32007-01-23 16:24:41 +010054#define BSG_DEFAULT_CMDS 64
FUJITA Tomonori292b7f22007-03-28 13:29:58 +020055#define BSG_MAX_DEVS 32768
Jens Axboe3d6392c2007-07-09 12:38:05 +020056
57#undef BSG_DEBUG
58
59#ifdef BSG_DEBUG
Harvey Harrison24c03d42008-05-01 04:35:17 -070060#define dprintk(fmt, args...) printk(KERN_ERR "%s: " fmt, __func__, ##args)
Jens Axboe3d6392c2007-07-09 12:38:05 +020061#else
62#define dprintk(fmt, args...)
63#endif
64
Jens Axboe3d6392c2007-07-09 12:38:05 +020065static DEFINE_MUTEX(bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +090066static DEFINE_IDR(bsg_minor_idr);
Jens Axboe3d6392c2007-07-09 12:38:05 +020067
Jens Axboe25fd1642007-07-17 08:52:29 +020068#define BSG_LIST_ARRAY_SIZE 8
Jens Axboe25fd1642007-07-17 08:52:29 +020069static struct hlist_head bsg_device_list[BSG_LIST_ARRAY_SIZE];
Jens Axboe3d6392c2007-07-09 12:38:05 +020070
71static struct class *bsg_class;
Jens Axboe46f6ef42007-07-17 08:56:10 +020072static int bsg_major;
Jens Axboe3d6392c2007-07-09 12:38:05 +020073
Jens Axboe5309cb32007-01-23 16:24:41 +010074static struct kmem_cache *bsg_cmd_cachep;
75
Jens Axboe3d6392c2007-07-09 12:38:05 +020076/*
77 * our internal command type
78 */
79struct bsg_command {
80 struct bsg_device *bd;
81 struct list_head list;
82 struct request *rq;
83 struct bio *bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +020084 struct bio *bidi_bio;
Jens Axboe3d6392c2007-07-09 12:38:05 +020085 int err;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +010086 struct sg_io_v4 hdr;
Jens Axboe3d6392c2007-07-09 12:38:05 +020087 char sense[SCSI_SENSE_BUFFERSIZE];
88};
89
90static void bsg_free_command(struct bsg_command *bc)
91{
92 struct bsg_device *bd = bc->bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +020093 unsigned long flags;
94
Jens Axboe5309cb32007-01-23 16:24:41 +010095 kmem_cache_free(bsg_cmd_cachep, bc);
Jens Axboe3d6392c2007-07-09 12:38:05 +020096
97 spin_lock_irqsave(&bd->lock, flags);
98 bd->queued_cmds--;
Jens Axboe3d6392c2007-07-09 12:38:05 +020099 spin_unlock_irqrestore(&bd->lock, flags);
100
101 wake_up(&bd->wq_free);
102}
103
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200104static struct bsg_command *bsg_alloc_command(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200105{
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200106 struct bsg_command *bc = ERR_PTR(-EINVAL);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200107
108 spin_lock_irq(&bd->lock);
109
110 if (bd->queued_cmds >= bd->max_queue)
111 goto out;
112
Jens Axboe3d6392c2007-07-09 12:38:05 +0200113 bd->queued_cmds++;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200114 spin_unlock_irq(&bd->lock);
115
Jens Axboe25fd1642007-07-17 08:52:29 +0200116 bc = kmem_cache_zalloc(bsg_cmd_cachep, GFP_KERNEL);
Jens Axboe5309cb32007-01-23 16:24:41 +0100117 if (unlikely(!bc)) {
118 spin_lock_irq(&bd->lock);
FUJITA Tomonori7e75d732007-01-24 09:05:54 +0100119 bd->queued_cmds--;
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200120 bc = ERR_PTR(-ENOMEM);
FUJITA Tomonori7e75d732007-01-24 09:05:54 +0100121 goto out;
Jens Axboe5309cb32007-01-23 16:24:41 +0100122 }
123
Jens Axboe3d6392c2007-07-09 12:38:05 +0200124 bc->bd = bd;
125 INIT_LIST_HEAD(&bc->list);
Jens Axboe5309cb32007-01-23 16:24:41 +0100126 dprintk("%s: returning free cmd %p\n", bd->name, bc);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200127 return bc;
128out:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200129 spin_unlock_irq(&bd->lock);
130 return bc;
131}
132
FUJITA Tomonori1c1133e2007-07-17 12:21:15 +0200133static inline struct hlist_head *bsg_dev_idx_hash(int index)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200134{
FUJITA Tomonori1c1133e2007-07-17 12:21:15 +0200135 return &bsg_device_list[index & (BSG_LIST_ARRAY_SIZE - 1)];
Jens Axboe3d6392c2007-07-09 12:38:05 +0200136}
137
Jens Axboe25fd1642007-07-17 08:52:29 +0200138static int bsg_io_schedule(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200139{
140 DEFINE_WAIT(wait);
141 int ret = 0;
142
143 spin_lock_irq(&bd->lock);
144
145 BUG_ON(bd->done_cmds > bd->queued_cmds);
146
147 /*
148 * -ENOSPC or -ENODATA? I'm going for -ENODATA, meaning "I have no
149 * work to do", even though we return -ENOSPC after this same test
150 * during bsg_write() -- there, it means our buffer can't have more
151 * bsg_commands added to it, thus has no space left.
152 */
153 if (bd->done_cmds == bd->queued_cmds) {
154 ret = -ENODATA;
155 goto unlock;
156 }
157
158 if (!test_bit(BSG_F_BLOCK, &bd->flags)) {
159 ret = -EAGAIN;
160 goto unlock;
161 }
162
Jens Axboe25fd1642007-07-17 08:52:29 +0200163 prepare_to_wait(&bd->wq_done, &wait, TASK_UNINTERRUPTIBLE);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200164 spin_unlock_irq(&bd->lock);
165 io_schedule();
166 finish_wait(&bd->wq_done, &wait);
167
Jens Axboe3d6392c2007-07-09 12:38:05 +0200168 return ret;
169unlock:
170 spin_unlock_irq(&bd->lock);
171 return ret;
172}
173
Jens Axboe165125e2007-07-24 09:28:11 +0200174static int blk_fill_sgv4_hdr_rq(struct request_queue *q, struct request *rq,
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900175 struct sg_io_v4 *hdr, struct bsg_device *bd,
Al Viroaeb5d722008-09-02 15:28:45 -0400176 fmode_t has_write_perm)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200177{
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900178 if (hdr->request_len > BLK_MAX_CDB) {
179 rq->cmd = kzalloc(hdr->request_len, GFP_KERNEL);
180 if (!rq->cmd)
181 return -ENOMEM;
182 }
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100183
184 if (copy_from_user(rq->cmd, (void *)(unsigned long)hdr->request,
185 hdr->request_len))
186 return -EFAULT;
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200187
188 if (hdr->subprotocol == BSG_SUB_PROTOCOL_SCSI_CMD) {
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900189 if (blk_verify_command(&q->cmd_filter, rq->cmd, has_write_perm))
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200190 return -EPERM;
191 } else if (!capable(CAP_SYS_RAWIO))
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100192 return -EPERM;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200193
194 /*
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100195 * fill in request structure
Jens Axboe3d6392c2007-07-09 12:38:05 +0200196 */
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100197 rq->cmd_len = hdr->request_len;
198 rq->cmd_type = REQ_TYPE_BLOCK_PC;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200199
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100200 rq->timeout = (hdr->timeout * HZ) / 1000;
201 if (!rq->timeout)
202 rq->timeout = q->sg_timeout;
203 if (!rq->timeout)
204 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
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 if (hdr->dout_xfer_len > (q->max_sectors << 9) ||
222 hdr->din_xfer_len > (q->max_sectors << 9))
223 return -EIO;
224
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200225 switch (hdr->protocol) {
226 case BSG_PROTOCOL_SCSI:
227 switch (hdr->subprotocol) {
228 case BSG_SUB_PROTOCOL_SCSI_CMD:
229 case BSG_SUB_PROTOCOL_SCSI_TRANSPORT:
230 break;
231 default:
232 ret = -EINVAL;
233 }
234 break;
235 default:
236 ret = -EINVAL;
237 }
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100238
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100239 *rw = hdr->dout_xfer_len ? WRITE : READ;
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200240 return ret;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100241}
242
243/*
244 * map sg_io_v4 to a request.
Jens Axboe3d6392c2007-07-09 12:38:05 +0200245 */
246static struct request *
Al Viroaeb5d722008-09-02 15:28:45 -0400247bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t has_write_perm)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200248{
Jens Axboe165125e2007-07-24 09:28:11 +0200249 struct request_queue *q = bd->queue;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200250 struct request *rq, *next_rq = NULL;
Jens Axboe25fd1642007-07-17 08:52:29 +0200251 int ret, rw;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100252 unsigned int dxfer_len;
253 void *dxferp = NULL;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200254
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100255 dprintk("map hdr %llx/%u %llx/%u\n", (unsigned long long) hdr->dout_xferp,
256 hdr->dout_xfer_len, (unsigned long long) hdr->din_xferp,
257 hdr->din_xfer_len);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200258
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100259 ret = bsg_validate_sgv4_hdr(q, hdr, &rw);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200260 if (ret)
261 return ERR_PTR(ret);
262
263 /*
264 * map scatter-gather elements seperately and string them to request
265 */
266 rq = blk_get_request(q, rw, GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200267 if (!rq)
268 return ERR_PTR(-ENOMEM);
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900269 ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, bd, has_write_perm);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200270 if (ret)
271 goto out;
272
273 if (rw == WRITE && hdr->din_xfer_len) {
274 if (!test_bit(QUEUE_FLAG_BIDI, &q->queue_flags)) {
275 ret = -EOPNOTSUPP;
276 goto out;
277 }
278
279 next_rq = blk_get_request(q, READ, GFP_KERNEL);
280 if (!next_rq) {
281 ret = -ENOMEM;
282 goto out;
283 }
284 rq->next_rq = next_rq;
James Bottomley40f62022008-01-25 20:05:55 -0600285 next_rq->cmd_type = rq->cmd_type;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200286
287 dxferp = (void*)(unsigned long)hdr->din_xferp;
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900288 ret = blk_rq_map_user(q, next_rq, NULL, dxferp,
289 hdr->din_xfer_len, GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200290 if (ret)
291 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200292 }
293
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100294 if (hdr->dout_xfer_len) {
295 dxfer_len = hdr->dout_xfer_len;
296 dxferp = (void*)(unsigned long)hdr->dout_xferp;
297 } else if (hdr->din_xfer_len) {
298 dxfer_len = hdr->din_xfer_len;
299 dxferp = (void*)(unsigned long)hdr->din_xferp;
300 } else
301 dxfer_len = 0;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200302
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100303 if (dxfer_len) {
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900304 ret = blk_rq_map_user(q, rq, NULL, dxferp, dxfer_len,
305 GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200306 if (ret)
307 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200308 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200309 return rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200310out:
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900311 if (rq->cmd != rq->__cmd)
312 kfree(rq->cmd);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200313 blk_put_request(rq);
314 if (next_rq) {
315 blk_rq_unmap_user(next_rq->bio);
316 blk_put_request(next_rq);
317 }
318 return ERR_PTR(ret);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200319}
320
321/*
322 * async completion call-back from the block layer, when scsi/ide/whatever
323 * calls end_that_request_last() on a request
324 */
325static void bsg_rq_end_io(struct request *rq, int uptodate)
326{
327 struct bsg_command *bc = rq->end_io_data;
328 struct bsg_device *bd = bc->bd;
329 unsigned long flags;
330
Jens Axboe5309cb32007-01-23 16:24:41 +0100331 dprintk("%s: finished rq %p bc %p, bio %p stat %d\n",
332 bd->name, rq, bc, bc->bio, uptodate);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200333
334 bc->hdr.duration = jiffies_to_msecs(jiffies - bc->hdr.duration);
335
336 spin_lock_irqsave(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200337 list_move_tail(&bc->list, &bd->done_list);
338 bd->done_cmds++;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200339 spin_unlock_irqrestore(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200340
341 wake_up(&bd->wq_done);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200342}
343
344/*
345 * do final setup of a 'bc' and submit the matching 'rq' to the block
346 * layer for io
347 */
Jens Axboe165125e2007-07-24 09:28:11 +0200348static void bsg_add_command(struct bsg_device *bd, struct request_queue *q,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200349 struct bsg_command *bc, struct request *rq)
350{
351 rq->sense = bc->sense;
352 rq->sense_len = 0;
353
354 /*
355 * add bc command to busy queue and submit rq for io
356 */
357 bc->rq = rq;
358 bc->bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200359 if (rq->next_rq)
360 bc->bidi_bio = rq->next_rq->bio;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200361 bc->hdr.duration = jiffies;
362 spin_lock_irq(&bd->lock);
363 list_add_tail(&bc->list, &bd->busy_list);
364 spin_unlock_irq(&bd->lock);
365
366 dprintk("%s: queueing rq %p, bc %p\n", bd->name, rq, bc);
367
368 rq->end_io_data = bc;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200369 blk_execute_rq_nowait(q, NULL, rq, 1, bsg_rq_end_io);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200370}
371
Jens Axboe25fd1642007-07-17 08:52:29 +0200372static struct bsg_command *bsg_next_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200373{
374 struct bsg_command *bc = NULL;
375
376 spin_lock_irq(&bd->lock);
377 if (bd->done_cmds) {
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900378 bc = list_first_entry(&bd->done_list, struct bsg_command, list);
Jens Axboe25fd1642007-07-17 08:52:29 +0200379 list_del(&bc->list);
380 bd->done_cmds--;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200381 }
382 spin_unlock_irq(&bd->lock);
383
384 return bc;
385}
386
387/*
388 * Get a finished command from the done list
389 */
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200390static struct bsg_command *bsg_get_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200391{
392 struct bsg_command *bc;
393 int ret;
394
395 do {
396 bc = bsg_next_done_cmd(bd);
397 if (bc)
398 break;
399
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200400 if (!test_bit(BSG_F_BLOCK, &bd->flags)) {
401 bc = ERR_PTR(-EAGAIN);
402 break;
403 }
404
405 ret = wait_event_interruptible(bd->wq_done, bd->done_cmds);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200406 if (ret) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200407 bc = ERR_PTR(-ERESTARTSYS);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200408 break;
409 }
410 } while (1);
411
412 dprintk("%s: returning done %p\n", bd->name, bc);
413
414 return bc;
415}
416
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100417static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr,
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200418 struct bio *bio, struct bio *bidi_bio)
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100419{
420 int ret = 0;
421
422 dprintk("rq %p bio %p %u\n", rq, bio, rq->errors);
423 /*
424 * fill in all the output members
425 */
426 hdr->device_status = status_byte(rq->errors);
427 hdr->transport_status = host_byte(rq->errors);
428 hdr->driver_status = driver_byte(rq->errors);
429 hdr->info = 0;
430 if (hdr->device_status || hdr->transport_status || hdr->driver_status)
431 hdr->info |= SG_INFO_CHECK;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100432 hdr->response_len = 0;
433
434 if (rq->sense_len && hdr->response) {
Jens Axboe25fd1642007-07-17 08:52:29 +0200435 int len = min_t(unsigned int, hdr->max_response_len,
436 rq->sense_len);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100437
438 ret = copy_to_user((void*)(unsigned long)hdr->response,
439 rq->sense, len);
440 if (!ret)
441 hdr->response_len = len;
442 else
443 ret = -EFAULT;
444 }
445
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200446 if (rq->next_rq) {
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100447 hdr->dout_resid = rq->data_len;
448 hdr->din_resid = rq->next_rq->data_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200449 blk_rq_unmap_user(bidi_bio);
450 blk_put_request(rq->next_rq);
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900451 } else if (rq_data_dir(rq) == READ)
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100452 hdr->din_resid = rq->data_len;
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900453 else
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100454 hdr->dout_resid = rq->data_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200455
James Bottomley2d507a02007-12-29 10:59:53 -0600456 /*
457 * If the request generated a negative error number, return it
458 * (providing we aren't already returning an error); if it's
459 * just a protocol response (i.e. non negative), that gets
460 * processed above.
461 */
462 if (!ret && rq->errors < 0)
463 ret = rq->errors;
464
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100465 blk_rq_unmap_user(bio);
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900466 if (rq->cmd != rq->__cmd)
467 kfree(rq->cmd);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100468 blk_put_request(rq);
469
470 return ret;
471}
472
Jens Axboe3d6392c2007-07-09 12:38:05 +0200473static int bsg_complete_all_commands(struct bsg_device *bd)
474{
475 struct bsg_command *bc;
476 int ret, tret;
477
478 dprintk("%s: entered\n", bd->name);
479
Jens Axboe3d6392c2007-07-09 12:38:05 +0200480 /*
481 * wait for all commands to complete
482 */
483 ret = 0;
484 do {
Jens Axboe25fd1642007-07-17 08:52:29 +0200485 ret = bsg_io_schedule(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200486 /*
487 * look for -ENODATA specifically -- we'll sometimes get
488 * -ERESTARTSYS when we've taken a signal, but we can't
489 * return until we're done freeing the queue, so ignore
490 * it. The signal will get handled when we're done freeing
491 * the bsg_device.
492 */
493 } while (ret != -ENODATA);
494
495 /*
496 * discard done commands
497 */
498 ret = 0;
499 do {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200500 spin_lock_irq(&bd->lock);
501 if (!bd->queued_cmds) {
502 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200503 break;
504 }
FUJITA Tomonoriefba1a32007-06-07 13:24:06 +0200505 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200506
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200507 bc = bsg_get_done_cmd(bd);
508 if (IS_ERR(bc))
509 break;
510
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200511 tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
512 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200513 if (!ret)
514 ret = tret;
515
516 bsg_free_command(bc);
517 } while (1);
518
519 return ret;
520}
521
Jens Axboe25fd1642007-07-17 08:52:29 +0200522static int
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200523__bsg_read(char __user *buf, size_t count, struct bsg_device *bd,
524 const struct iovec *iov, ssize_t *bytes_read)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200525{
526 struct bsg_command *bc;
527 int nr_commands, ret;
528
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100529 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200530 return -EINVAL;
531
532 ret = 0;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100533 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200534 while (nr_commands) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200535 bc = bsg_get_done_cmd(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200536 if (IS_ERR(bc)) {
537 ret = PTR_ERR(bc);
538 break;
539 }
540
541 /*
542 * this is the only case where we need to copy data back
543 * after completing the request. so do that here,
544 * bsg_complete_work() cannot do that for us
545 */
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200546 ret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
547 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200548
Jens Axboe25fd1642007-07-17 08:52:29 +0200549 if (copy_to_user(buf, &bc->hdr, sizeof(bc->hdr)))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200550 ret = -EFAULT;
551
552 bsg_free_command(bc);
553
554 if (ret)
555 break;
556
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100557 buf += sizeof(struct sg_io_v4);
558 *bytes_read += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200559 nr_commands--;
560 }
561
562 return ret;
563}
564
565static inline void bsg_set_block(struct bsg_device *bd, struct file *file)
566{
567 if (file->f_flags & O_NONBLOCK)
568 clear_bit(BSG_F_BLOCK, &bd->flags);
569 else
570 set_bit(BSG_F_BLOCK, &bd->flags);
571}
572
Jens Axboe25fd1642007-07-17 08:52:29 +0200573/*
574 * Check if the error is a "real" error that we should return.
575 */
Jens Axboe3d6392c2007-07-09 12:38:05 +0200576static inline int err_block_err(int ret)
577{
578 if (ret && ret != -ENOSPC && ret != -ENODATA && ret != -EAGAIN)
579 return 1;
580
581 return 0;
582}
583
584static ssize_t
585bsg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
586{
587 struct bsg_device *bd = file->private_data;
588 int ret;
589 ssize_t bytes_read;
590
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100591 dprintk("%s: read %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200592
593 bsg_set_block(bd, file);
Adel Gadllah0b07de82008-06-26 13:48:27 +0200594
Jens Axboe3d6392c2007-07-09 12:38:05 +0200595 bytes_read = 0;
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200596 ret = __bsg_read(buf, count, bd, NULL, &bytes_read);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200597 *ppos = bytes_read;
598
599 if (!bytes_read || (bytes_read && err_block_err(ret)))
600 bytes_read = ret;
601
602 return bytes_read;
603}
604
Jens Axboe25fd1642007-07-17 08:52:29 +0200605static int __bsg_write(struct bsg_device *bd, const char __user *buf,
Al Viroaeb5d722008-09-02 15:28:45 -0400606 size_t count, ssize_t *bytes_written,
607 fmode_t has_write_perm)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200608{
609 struct bsg_command *bc;
610 struct request *rq;
611 int ret, nr_commands;
612
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100613 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200614 return -EINVAL;
615
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100616 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200617 rq = NULL;
618 bc = NULL;
619 ret = 0;
620 while (nr_commands) {
Jens Axboe165125e2007-07-24 09:28:11 +0200621 struct request_queue *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200622
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200623 bc = bsg_alloc_command(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200624 if (IS_ERR(bc)) {
625 ret = PTR_ERR(bc);
626 bc = NULL;
627 break;
628 }
629
Jens Axboe3d6392c2007-07-09 12:38:05 +0200630 if (copy_from_user(&bc->hdr, buf, sizeof(bc->hdr))) {
631 ret = -EFAULT;
632 break;
633 }
634
635 /*
636 * get a request, fill in the blanks, and add to request queue
637 */
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900638 rq = bsg_map_hdr(bd, &bc->hdr, has_write_perm);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200639 if (IS_ERR(rq)) {
640 ret = PTR_ERR(rq);
641 rq = NULL;
642 break;
643 }
644
645 bsg_add_command(bd, q, bc, rq);
646 bc = NULL;
647 rq = NULL;
648 nr_commands--;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100649 buf += sizeof(struct sg_io_v4);
Jens Axboe25fd1642007-07-17 08:52:29 +0200650 *bytes_written += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200651 }
652
Jens Axboe3d6392c2007-07-09 12:38:05 +0200653 if (bc)
654 bsg_free_command(bc);
655
656 return ret;
657}
658
659static ssize_t
660bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
661{
662 struct bsg_device *bd = file->private_data;
Jens Axboe25fd1642007-07-17 08:52:29 +0200663 ssize_t bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200664 int ret;
665
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100666 dprintk("%s: write %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200667
668 bsg_set_block(bd, file);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200669
Jens Axboe25fd1642007-07-17 08:52:29 +0200670 bytes_written = 0;
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900671 ret = __bsg_write(bd, buf, count, &bytes_written,
672 file->f_mode & FMODE_WRITE);
673
Jens Axboe25fd1642007-07-17 08:52:29 +0200674 *ppos = bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200675
676 /*
677 * return bytes written on non-fatal errors
678 */
Jens Axboe25fd1642007-07-17 08:52:29 +0200679 if (!bytes_written || (bytes_written && err_block_err(ret)))
680 bytes_written = ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200681
Jens Axboe25fd1642007-07-17 08:52:29 +0200682 dprintk("%s: returning %Zd\n", bd->name, bytes_written);
683 return bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200684}
685
Jens Axboe3d6392c2007-07-09 12:38:05 +0200686static struct bsg_device *bsg_alloc_device(void)
687{
Jens Axboe3d6392c2007-07-09 12:38:05 +0200688 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200689
690 bd = kzalloc(sizeof(struct bsg_device), GFP_KERNEL);
691 if (unlikely(!bd))
692 return NULL;
693
694 spin_lock_init(&bd->lock);
695
Jens Axboe5309cb32007-01-23 16:24:41 +0100696 bd->max_queue = BSG_DEFAULT_CMDS;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200697
698 INIT_LIST_HEAD(&bd->busy_list);
699 INIT_LIST_HEAD(&bd->done_list);
700 INIT_HLIST_NODE(&bd->dev_list);
701
702 init_waitqueue_head(&bd->wq_free);
703 init_waitqueue_head(&bd->wq_done);
704 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200705}
706
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900707static void bsg_kref_release_function(struct kref *kref)
708{
709 struct bsg_class_device *bcd =
710 container_of(kref, struct bsg_class_device, ref);
James Bottomley8df5fc02008-07-07 15:50:01 -0500711 struct device *parent = bcd->parent;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900712
713 if (bcd->release)
714 bcd->release(bcd->parent);
715
James Bottomley8df5fc02008-07-07 15:50:01 -0500716 put_device(parent);
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900717}
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;
Adel Gadllah0b07de82008-06-26 13:48:27 +0200777
Jens Axboe3d6392c2007-07-09 12:38:05 +0200778 bsg_set_block(bd, file);
779
780 atomic_set(&bd->ref_count, 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200781 mutex_lock(&bsg_mutex);
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900782 hlist_add_head(&bd->dev_list, bsg_dev_idx_hash(iminor(inode)));
Jens Axboe3d6392c2007-07-09 12:38:05 +0200783
Tony Jonesee959b02008-02-22 00:13:36 +0100784 strncpy(bd->name, rq->bsg_dev.class_dev->bus_id, sizeof(bd->name) - 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200785 dprintk("bound to <%s>, max queue %d\n",
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100786 format_dev_t(buf, inode->i_rdev), bd->max_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200787
788 mutex_unlock(&bsg_mutex);
789 return bd;
790}
791
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900792static struct bsg_device *__bsg_get_device(int minor, struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200793{
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900794 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200795 struct hlist_node *entry;
796
797 mutex_lock(&bsg_mutex);
798
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900799 hlist_for_each_entry(bd, entry, bsg_dev_idx_hash(minor), dev_list) {
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900800 if (bd->queue == q) {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200801 atomic_inc(&bd->ref_count);
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900802 goto found;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200803 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200804 }
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900805 bd = NULL;
806found:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200807 mutex_unlock(&bsg_mutex);
808 return bd;
809}
810
811static struct bsg_device *bsg_get_device(struct inode *inode, struct file *file)
812{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900813 struct bsg_device *bd;
814 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200815
Jens Axboe3d6392c2007-07-09 12:38:05 +0200816 /*
817 * find the class device
818 */
Jens Axboe3d6392c2007-07-09 12:38:05 +0200819 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900820 bcd = idr_find(&bsg_minor_idr, iminor(inode));
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900821 if (bcd)
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900822 kref_get(&bcd->ref);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200823 mutex_unlock(&bsg_mutex);
824
825 if (!bcd)
826 return ERR_PTR(-ENODEV);
827
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900828 bd = __bsg_get_device(iminor(inode), bcd->queue);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900829 if (bd)
830 return bd;
831
832 bd = bsg_add_device(inode, bcd->queue, file);
833 if (IS_ERR(bd))
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900834 kref_put(&bcd->ref, bsg_kref_release_function);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900835
836 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200837}
838
839static int bsg_open(struct inode *inode, struct file *file)
840{
Jonathan Corbet75bd2ef2008-05-15 09:09:23 -0600841 struct bsg_device *bd;
842
843 lock_kernel();
844 bd = bsg_get_device(inode, file);
845 unlock_kernel();
Jens Axboe3d6392c2007-07-09 12:38:05 +0200846
847 if (IS_ERR(bd))
848 return PTR_ERR(bd);
849
850 file->private_data = bd;
851 return 0;
852}
853
854static int bsg_release(struct inode *inode, struct file *file)
855{
856 struct bsg_device *bd = file->private_data;
857
858 file->private_data = NULL;
859 return bsg_put_device(bd);
860}
861
862static unsigned int bsg_poll(struct file *file, poll_table *wait)
863{
864 struct bsg_device *bd = file->private_data;
865 unsigned int mask = 0;
866
867 poll_wait(file, &bd->wq_done, wait);
868 poll_wait(file, &bd->wq_free, wait);
869
870 spin_lock_irq(&bd->lock);
871 if (!list_empty(&bd->done_list))
872 mask |= POLLIN | POLLRDNORM;
873 if (bd->queued_cmds >= bd->max_queue)
874 mask |= POLLOUT;
875 spin_unlock_irq(&bd->lock);
876
877 return mask;
878}
879
Jens Axboe25fd1642007-07-17 08:52:29 +0200880static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200881{
882 struct bsg_device *bd = file->private_data;
883 int __user *uarg = (int __user *) arg;
James Bottomley2d507a02007-12-29 10:59:53 -0600884 int ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200885
Jens Axboe3d6392c2007-07-09 12:38:05 +0200886 switch (cmd) {
887 /*
888 * our own ioctls
889 */
890 case SG_GET_COMMAND_Q:
891 return put_user(bd->max_queue, uarg);
Jens Axboe5309cb32007-01-23 16:24:41 +0100892 case SG_SET_COMMAND_Q: {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200893 int queue;
894
895 if (get_user(queue, uarg))
896 return -EFAULT;
Jens Axboe5309cb32007-01-23 16:24:41 +0100897 if (queue < 1)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200898 return -EINVAL;
899
Jens Axboe5309cb32007-01-23 16:24:41 +0100900 spin_lock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200901 bd->max_queue = queue;
Jens Axboe5309cb32007-01-23 16:24:41 +0100902 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200903 return 0;
904 }
905
906 /*
907 * SCSI/sg ioctls
908 */
909 case SG_GET_VERSION_NUM:
910 case SCSI_IOCTL_GET_IDLUN:
911 case SCSI_IOCTL_GET_BUS_NUMBER:
912 case SG_SET_TIMEOUT:
913 case SG_GET_TIMEOUT:
914 case SG_GET_RESERVED_SIZE:
915 case SG_SET_RESERVED_SIZE:
916 case SG_EMULATED_HOST:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200917 case SCSI_IOCTL_SEND_COMMAND: {
918 void __user *uarg = (void __user *) arg;
Al Viro74f3c8a2007-08-27 15:38:10 -0400919 return scsi_cmd_ioctl(bd->queue, NULL, file->f_mode, cmd, uarg);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200920 }
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100921 case SG_IO: {
922 struct request *rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200923 struct bio *bio, *bidi_bio = NULL;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100924 struct sg_io_v4 hdr;
925
926 if (copy_from_user(&hdr, uarg, sizeof(hdr)))
927 return -EFAULT;
928
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900929 rq = bsg_map_hdr(bd, &hdr, file->f_mode & FMODE_WRITE);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100930 if (IS_ERR(rq))
931 return PTR_ERR(rq);
932
933 bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200934 if (rq->next_rq)
935 bidi_bio = rq->next_rq->bio;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200936 blk_execute_rq(bd->queue, NULL, rq, 0);
James Bottomley2d507a02007-12-29 10:59:53 -0600937 ret = blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100938
939 if (copy_to_user(uarg, &hdr, sizeof(hdr)))
940 return -EFAULT;
Jens Axboeb711afa2006-12-20 11:25:23 +0100941
James Bottomley2d507a02007-12-29 10:59:53 -0600942 return ret;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100943 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200944 /*
945 * block device ioctls
946 */
947 default:
948#if 0
949 return ioctl_by_bdev(bd->bdev, cmd, arg);
950#else
951 return -ENOTTY;
952#endif
953 }
954}
955
Arjan van de Ven7344be02007-10-15 11:01:53 +0200956static const struct file_operations bsg_fops = {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200957 .read = bsg_read,
958 .write = bsg_write,
959 .poll = bsg_poll,
960 .open = bsg_open,
961 .release = bsg_release,
Jens Axboe25fd1642007-07-17 08:52:29 +0200962 .unlocked_ioctl = bsg_ioctl,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200963 .owner = THIS_MODULE,
964};
965
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200966void bsg_unregister_queue(struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200967{
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200968 struct bsg_class_device *bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200969
FUJITA Tomonoridf468822007-07-21 13:23:25 +0900970 if (!bcd->class_dev)
971 return;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200972
973 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900974 idr_remove(&bsg_minor_idr, bcd->minor);
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200975 sysfs_remove_link(&q->kobj, "bsg");
Tony Jonesee959b02008-02-22 00:13:36 +0100976 device_unregister(bcd->class_dev);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200977 bcd->class_dev = NULL;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900978 kref_put(&bcd->ref, bsg_kref_release_function);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200979 mutex_unlock(&bsg_mutex);
980}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +0200981EXPORT_SYMBOL_GPL(bsg_unregister_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200982
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900983int bsg_register_queue(struct request_queue *q, struct device *parent,
984 const char *name, void (*release)(struct device *))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200985{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900986 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200987 dev_t dev;
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900988 int ret, minor;
Tony Jonesee959b02008-02-22 00:13:36 +0100989 struct device *class_dev = NULL;
James Bottomley39dca552007-07-20 18:22:17 -0500990 const char *devname;
991
992 if (name)
993 devname = name;
994 else
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900995 devname = parent->bus_id;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200996
997 /*
998 * we need a proper transport to send commands, not a stacked device
999 */
1000 if (!q->request_fn)
1001 return 0;
1002
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001003 bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001004 memset(bcd, 0, sizeof(*bcd));
Jens Axboe3d6392c2007-07-09 12:38:05 +02001005
1006 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001007
1008 ret = idr_pre_get(&bsg_minor_idr, GFP_KERNEL);
1009 if (!ret) {
1010 ret = -ENOMEM;
1011 goto unlock;
1012 }
1013
1014 ret = idr_get_new(&bsg_minor_idr, bcd, &minor);
1015 if (ret < 0)
1016 goto unlock;
1017
1018 if (minor >= BSG_MAX_DEVS) {
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001019 printk(KERN_ERR "bsg: too many bsg devices\n");
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001020 ret = -EINVAL;
1021 goto remove_idr;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001022 }
1023
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001024 bcd->minor = minor;
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001025 bcd->queue = q;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001026 bcd->parent = get_device(parent);
1027 bcd->release = release;
1028 kref_init(&bcd->ref);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001029 dev = MKDEV(bsg_major, bcd->minor);
Greg Kroah-Hartman1ff9f542008-07-21 20:03:34 -07001030 class_dev = device_create(bsg_class, parent, dev, NULL, "%s", devname);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001031 if (IS_ERR(class_dev)) {
1032 ret = PTR_ERR(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001033 goto put_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001034 }
1035 bcd->class_dev = class_dev;
1036
Linus Torvaldsabce8912007-07-16 11:18:23 -07001037 if (q->kobj.sd) {
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001038 ret = sysfs_create_link(&q->kobj, &bcd->class_dev->kobj, "bsg");
1039 if (ret)
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001040 goto unregister_class_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001041 }
1042
Jens Axboe3d6392c2007-07-09 12:38:05 +02001043 mutex_unlock(&bsg_mutex);
1044 return 0;
James Bottomley6826ee42007-07-20 16:50:10 -05001045
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001046unregister_class_dev:
Tony Jonesee959b02008-02-22 00:13:36 +01001047 device_unregister(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001048put_dev:
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001049 put_device(parent);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001050remove_idr:
1051 idr_remove(&bsg_minor_idr, minor);
1052unlock:
Jens Axboe264a0472007-01-23 16:30:17 +01001053 mutex_unlock(&bsg_mutex);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001054 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001055}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +02001056EXPORT_SYMBOL_GPL(bsg_register_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001057
Greg Kroah-Hartman7e7654a2007-09-12 15:06:57 -07001058static struct cdev bsg_cdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001059
Jens Axboe3d6392c2007-07-09 12:38:05 +02001060static int __init bsg_init(void)
1061{
1062 int ret, i;
Jens Axboe46f6ef42007-07-17 08:56:10 +02001063 dev_t devid;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001064
Jens Axboe5309cb32007-01-23 16:24:41 +01001065 bsg_cmd_cachep = kmem_cache_create("bsg_cmd",
Paul Mundt20c2df82007-07-20 10:11:58 +09001066 sizeof(struct bsg_command), 0, 0, NULL);
Jens Axboe5309cb32007-01-23 16:24:41 +01001067 if (!bsg_cmd_cachep) {
1068 printk(KERN_ERR "bsg: failed creating slab cache\n");
1069 return -ENOMEM;
1070 }
1071
Jens Axboe25fd1642007-07-17 08:52:29 +02001072 for (i = 0; i < BSG_LIST_ARRAY_SIZE; i++)
Jens Axboe3d6392c2007-07-09 12:38:05 +02001073 INIT_HLIST_HEAD(&bsg_device_list[i]);
1074
1075 bsg_class = class_create(THIS_MODULE, "bsg");
Jens Axboe5309cb32007-01-23 16:24:41 +01001076 if (IS_ERR(bsg_class)) {
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001077 ret = PTR_ERR(bsg_class);
1078 goto destroy_kmemcache;
Jens Axboe5309cb32007-01-23 16:24:41 +01001079 }
Jens Axboe3d6392c2007-07-09 12:38:05 +02001080
Jens Axboe46f6ef42007-07-17 08:56:10 +02001081 ret = alloc_chrdev_region(&devid, 0, BSG_MAX_DEVS, "bsg");
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001082 if (ret)
1083 goto destroy_bsg_class;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001084
Jens Axboe46f6ef42007-07-17 08:56:10 +02001085 bsg_major = MAJOR(devid);
1086
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001087 cdev_init(&bsg_cdev, &bsg_fops);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001088 ret = cdev_add(&bsg_cdev, MKDEV(bsg_major, 0), BSG_MAX_DEVS);
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001089 if (ret)
1090 goto unregister_chrdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001091
Jens Axboe5d3a8cd2007-07-17 15:10:09 +02001092 printk(KERN_INFO BSG_DESCRIPTION " version " BSG_VERSION
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001093 " loaded (major %d)\n", bsg_major);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001094 return 0;
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001095unregister_chrdev:
1096 unregister_chrdev_region(MKDEV(bsg_major, 0), BSG_MAX_DEVS);
1097destroy_bsg_class:
1098 class_destroy(bsg_class);
1099destroy_kmemcache:
1100 kmem_cache_destroy(bsg_cmd_cachep);
1101 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001102}
1103
1104MODULE_AUTHOR("Jens Axboe");
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001105MODULE_DESCRIPTION(BSG_DESCRIPTION);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001106MODULE_LICENSE("GPL");
1107
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001108device_initcall(bsg_init);