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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 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 *
Boaz Harroshc1c20122009-02-03 07:47:29 +0100247bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t has_write_perm,
248 u8 *sense)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200249{
Jens Axboe165125e2007-07-24 09:28:11 +0200250 struct request_queue *q = bd->queue;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200251 struct request *rq, *next_rq = NULL;
Jens Axboe25fd1642007-07-17 08:52:29 +0200252 int ret, rw;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100253 unsigned int dxfer_len;
254 void *dxferp = NULL;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200255
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100256 dprintk("map hdr %llx/%u %llx/%u\n", (unsigned long long) hdr->dout_xferp,
257 hdr->dout_xfer_len, (unsigned long long) hdr->din_xferp,
258 hdr->din_xfer_len);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200259
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100260 ret = bsg_validate_sgv4_hdr(q, hdr, &rw);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200261 if (ret)
262 return ERR_PTR(ret);
263
264 /*
265 * map scatter-gather elements seperately and string them to request
266 */
267 rq = blk_get_request(q, rw, GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200268 if (!rq)
269 return ERR_PTR(-ENOMEM);
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900270 ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, bd, has_write_perm);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200271 if (ret)
272 goto out;
273
274 if (rw == WRITE && hdr->din_xfer_len) {
275 if (!test_bit(QUEUE_FLAG_BIDI, &q->queue_flags)) {
276 ret = -EOPNOTSUPP;
277 goto out;
278 }
279
280 next_rq = blk_get_request(q, READ, GFP_KERNEL);
281 if (!next_rq) {
282 ret = -ENOMEM;
283 goto out;
284 }
285 rq->next_rq = next_rq;
James Bottomley40f62022008-01-25 20:05:55 -0600286 next_rq->cmd_type = rq->cmd_type;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200287
288 dxferp = (void*)(unsigned long)hdr->din_xferp;
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900289 ret = blk_rq_map_user(q, next_rq, NULL, dxferp,
290 hdr->din_xfer_len, GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200291 if (ret)
292 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200293 }
294
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100295 if (hdr->dout_xfer_len) {
296 dxfer_len = hdr->dout_xfer_len;
297 dxferp = (void*)(unsigned long)hdr->dout_xferp;
298 } else if (hdr->din_xfer_len) {
299 dxfer_len = hdr->din_xfer_len;
300 dxferp = (void*)(unsigned long)hdr->din_xferp;
301 } else
302 dxfer_len = 0;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200303
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100304 if (dxfer_len) {
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900305 ret = blk_rq_map_user(q, rq, NULL, dxferp, dxfer_len,
306 GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200307 if (ret)
308 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200309 }
Boaz Harroshc1c20122009-02-03 07:47:29 +0100310
311 rq->sense = sense;
312 rq->sense_len = 0;
313
Jens Axboe3d6392c2007-07-09 12:38:05 +0200314 return rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200315out:
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900316 if (rq->cmd != rq->__cmd)
317 kfree(rq->cmd);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200318 blk_put_request(rq);
319 if (next_rq) {
320 blk_rq_unmap_user(next_rq->bio);
321 blk_put_request(next_rq);
322 }
323 return ERR_PTR(ret);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200324}
325
326/*
327 * async completion call-back from the block layer, when scsi/ide/whatever
328 * calls end_that_request_last() on a request
329 */
330static void bsg_rq_end_io(struct request *rq, int uptodate)
331{
332 struct bsg_command *bc = rq->end_io_data;
333 struct bsg_device *bd = bc->bd;
334 unsigned long flags;
335
Jens Axboe5309cb32007-01-23 16:24:41 +0100336 dprintk("%s: finished rq %p bc %p, bio %p stat %d\n",
337 bd->name, rq, bc, bc->bio, uptodate);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200338
339 bc->hdr.duration = jiffies_to_msecs(jiffies - bc->hdr.duration);
340
341 spin_lock_irqsave(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200342 list_move_tail(&bc->list, &bd->done_list);
343 bd->done_cmds++;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200344 spin_unlock_irqrestore(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200345
346 wake_up(&bd->wq_done);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200347}
348
349/*
350 * do final setup of a 'bc' and submit the matching 'rq' to the block
351 * layer for io
352 */
Jens Axboe165125e2007-07-24 09:28:11 +0200353static void bsg_add_command(struct bsg_device *bd, struct request_queue *q,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200354 struct bsg_command *bc, struct request *rq)
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;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200371 blk_execute_rq_nowait(q, NULL, rq, 1, 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) {
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100449 hdr->dout_resid = rq->data_len;
450 hdr->din_resid = rq->next_rq->data_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200451 blk_rq_unmap_user(bidi_bio);
452 blk_put_request(rq->next_rq);
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900453 } else if (rq_data_dir(rq) == READ)
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100454 hdr->din_resid = rq->data_len;
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900455 else
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100456 hdr->dout_resid = rq->data_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200457
James Bottomley2d507a02007-12-29 10:59:53 -0600458 /*
459 * If the request generated a negative error number, return it
460 * (providing we aren't already returning an error); if it's
461 * just a protocol response (i.e. non negative), that gets
462 * processed above.
463 */
464 if (!ret && rq->errors < 0)
465 ret = rq->errors;
466
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100467 blk_rq_unmap_user(bio);
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900468 if (rq->cmd != rq->__cmd)
469 kfree(rq->cmd);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100470 blk_put_request(rq);
471
472 return ret;
473}
474
Jens Axboe3d6392c2007-07-09 12:38:05 +0200475static int bsg_complete_all_commands(struct bsg_device *bd)
476{
477 struct bsg_command *bc;
478 int ret, tret;
479
480 dprintk("%s: entered\n", bd->name);
481
Jens Axboe3d6392c2007-07-09 12:38:05 +0200482 /*
483 * wait for all commands to complete
484 */
485 ret = 0;
486 do {
Jens Axboe25fd1642007-07-17 08:52:29 +0200487 ret = bsg_io_schedule(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200488 /*
489 * look for -ENODATA specifically -- we'll sometimes get
490 * -ERESTARTSYS when we've taken a signal, but we can't
491 * return until we're done freeing the queue, so ignore
492 * it. The signal will get handled when we're done freeing
493 * the bsg_device.
494 */
495 } while (ret != -ENODATA);
496
497 /*
498 * discard done commands
499 */
500 ret = 0;
501 do {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200502 spin_lock_irq(&bd->lock);
503 if (!bd->queued_cmds) {
504 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200505 break;
506 }
FUJITA Tomonoriefba1a32007-06-07 13:24:06 +0200507 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200508
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200509 bc = bsg_get_done_cmd(bd);
510 if (IS_ERR(bc))
511 break;
512
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200513 tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
514 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200515 if (!ret)
516 ret = tret;
517
518 bsg_free_command(bc);
519 } while (1);
520
521 return ret;
522}
523
Jens Axboe25fd1642007-07-17 08:52:29 +0200524static int
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200525__bsg_read(char __user *buf, size_t count, struct bsg_device *bd,
526 const struct iovec *iov, ssize_t *bytes_read)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200527{
528 struct bsg_command *bc;
529 int nr_commands, ret;
530
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100531 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200532 return -EINVAL;
533
534 ret = 0;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100535 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200536 while (nr_commands) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200537 bc = bsg_get_done_cmd(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200538 if (IS_ERR(bc)) {
539 ret = PTR_ERR(bc);
540 break;
541 }
542
543 /*
544 * this is the only case where we need to copy data back
545 * after completing the request. so do that here,
546 * bsg_complete_work() cannot do that for us
547 */
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200548 ret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
549 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200550
Jens Axboe25fd1642007-07-17 08:52:29 +0200551 if (copy_to_user(buf, &bc->hdr, sizeof(bc->hdr)))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200552 ret = -EFAULT;
553
554 bsg_free_command(bc);
555
556 if (ret)
557 break;
558
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100559 buf += sizeof(struct sg_io_v4);
560 *bytes_read += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200561 nr_commands--;
562 }
563
564 return ret;
565}
566
567static inline void bsg_set_block(struct bsg_device *bd, struct file *file)
568{
569 if (file->f_flags & O_NONBLOCK)
570 clear_bit(BSG_F_BLOCK, &bd->flags);
571 else
572 set_bit(BSG_F_BLOCK, &bd->flags);
573}
574
Jens Axboe25fd1642007-07-17 08:52:29 +0200575/*
576 * Check if the error is a "real" error that we should return.
577 */
Jens Axboe3d6392c2007-07-09 12:38:05 +0200578static inline int err_block_err(int ret)
579{
580 if (ret && ret != -ENOSPC && ret != -ENODATA && ret != -EAGAIN)
581 return 1;
582
583 return 0;
584}
585
586static ssize_t
587bsg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
588{
589 struct bsg_device *bd = file->private_data;
590 int ret;
591 ssize_t bytes_read;
592
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100593 dprintk("%s: read %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200594
595 bsg_set_block(bd, file);
Adel Gadllah0b07de82008-06-26 13:48:27 +0200596
Jens Axboe3d6392c2007-07-09 12:38:05 +0200597 bytes_read = 0;
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200598 ret = __bsg_read(buf, count, bd, NULL, &bytes_read);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200599 *ppos = bytes_read;
600
601 if (!bytes_read || (bytes_read && err_block_err(ret)))
602 bytes_read = ret;
603
604 return bytes_read;
605}
606
Jens Axboe25fd1642007-07-17 08:52:29 +0200607static int __bsg_write(struct bsg_device *bd, const char __user *buf,
Al Viroaeb5d722008-09-02 15:28:45 -0400608 size_t count, ssize_t *bytes_written,
609 fmode_t has_write_perm)
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 */
Boaz Harroshc1c20122009-02-03 07:47:29 +0100640 rq = bsg_map_hdr(bd, &bc->hdr, has_write_perm, bc->sense);
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);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200671
Jens Axboe25fd1642007-07-17 08:52:29 +0200672 bytes_written = 0;
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900673 ret = __bsg_write(bd, buf, count, &bytes_written,
674 file->f_mode & FMODE_WRITE);
675
Jens Axboe25fd1642007-07-17 08:52:29 +0200676 *ppos = bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200677
678 /*
679 * return bytes written on non-fatal errors
680 */
Jens Axboe25fd1642007-07-17 08:52:29 +0200681 if (!bytes_written || (bytes_written && err_block_err(ret)))
682 bytes_written = ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200683
Jens Axboe25fd1642007-07-17 08:52:29 +0200684 dprintk("%s: returning %Zd\n", bd->name, bytes_written);
685 return bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200686}
687
Jens Axboe3d6392c2007-07-09 12:38:05 +0200688static struct bsg_device *bsg_alloc_device(void)
689{
Jens Axboe3d6392c2007-07-09 12:38:05 +0200690 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200691
692 bd = kzalloc(sizeof(struct bsg_device), GFP_KERNEL);
693 if (unlikely(!bd))
694 return NULL;
695
696 spin_lock_init(&bd->lock);
697
Jens Axboe5309cb32007-01-23 16:24:41 +0100698 bd->max_queue = BSG_DEFAULT_CMDS;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200699
700 INIT_LIST_HEAD(&bd->busy_list);
701 INIT_LIST_HEAD(&bd->done_list);
702 INIT_HLIST_NODE(&bd->dev_list);
703
704 init_waitqueue_head(&bd->wq_free);
705 init_waitqueue_head(&bd->wq_done);
706 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200707}
708
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900709static void bsg_kref_release_function(struct kref *kref)
710{
711 struct bsg_class_device *bcd =
712 container_of(kref, struct bsg_class_device, ref);
James Bottomley8df5fc02008-07-07 15:50:01 -0500713 struct device *parent = bcd->parent;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900714
715 if (bcd->release)
716 bcd->release(bcd->parent);
717
James Bottomley8df5fc02008-07-07 15:50:01 -0500718 put_device(parent);
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900719}
720
Jens Axboe3d6392c2007-07-09 12:38:05 +0200721static int bsg_put_device(struct bsg_device *bd)
722{
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900723 int ret = 0, do_free;
724 struct request_queue *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200725
726 mutex_lock(&bsg_mutex);
727
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900728 do_free = atomic_dec_and_test(&bd->ref_count);
FUJITA Tomonori3f27e3e2008-05-29 07:56:55 +0900729 if (!do_free) {
730 mutex_unlock(&bsg_mutex);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200731 goto out;
FUJITA Tomonori3f27e3e2008-05-29 07:56:55 +0900732 }
733
734 hlist_del(&bd->dev_list);
735 mutex_unlock(&bsg_mutex);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200736
737 dprintk("%s: tearing down\n", bd->name);
738
739 /*
740 * close can always block
741 */
742 set_bit(BSG_F_BLOCK, &bd->flags);
743
744 /*
745 * correct error detection baddies here again. it's the responsibility
746 * of the app to properly reap commands before close() if it wants
747 * fool-proof error detection
748 */
749 ret = bsg_complete_all_commands(bd);
750
Jens Axboe5309cb32007-01-23 16:24:41 +0100751 kfree(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200752out:
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900753 kref_put(&q->bsg_dev.ref, bsg_kref_release_function);
754 if (do_free)
755 blk_put_queue(q);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200756 return ret;
757}
758
759static struct bsg_device *bsg_add_device(struct inode *inode,
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200760 struct request_queue *rq,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200761 struct file *file)
762{
Jens Axboe25fd1642007-07-17 08:52:29 +0200763 struct bsg_device *bd;
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900764 int ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200765#ifdef BSG_DEBUG
766 unsigned char buf[32];
767#endif
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900768 ret = blk_get_queue(rq);
769 if (ret)
770 return ERR_PTR(-ENXIO);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200771
772 bd = bsg_alloc_device();
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900773 if (!bd) {
774 blk_put_queue(rq);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200775 return ERR_PTR(-ENOMEM);
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900776 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200777
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200778 bd->queue = rq;
Adel Gadllah0b07de82008-06-26 13:48:27 +0200779
Jens Axboe3d6392c2007-07-09 12:38:05 +0200780 bsg_set_block(bd, file);
781
782 atomic_set(&bd->ref_count, 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200783 mutex_lock(&bsg_mutex);
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900784 hlist_add_head(&bd->dev_list, bsg_dev_idx_hash(iminor(inode)));
Jens Axboe3d6392c2007-07-09 12:38:05 +0200785
Kay Sievers3ada8b72009-01-06 10:44:43 -0800786 strncpy(bd->name, dev_name(rq->bsg_dev.class_dev), sizeof(bd->name) - 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200787 dprintk("bound to <%s>, max queue %d\n",
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100788 format_dev_t(buf, inode->i_rdev), bd->max_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200789
790 mutex_unlock(&bsg_mutex);
791 return bd;
792}
793
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900794static struct bsg_device *__bsg_get_device(int minor, struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200795{
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900796 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200797 struct hlist_node *entry;
798
799 mutex_lock(&bsg_mutex);
800
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900801 hlist_for_each_entry(bd, entry, bsg_dev_idx_hash(minor), dev_list) {
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900802 if (bd->queue == q) {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200803 atomic_inc(&bd->ref_count);
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900804 goto found;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200805 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200806 }
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900807 bd = NULL;
808found:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200809 mutex_unlock(&bsg_mutex);
810 return bd;
811}
812
813static struct bsg_device *bsg_get_device(struct inode *inode, struct file *file)
814{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900815 struct bsg_device *bd;
816 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200817
Jens Axboe3d6392c2007-07-09 12:38:05 +0200818 /*
819 * find the class device
820 */
Jens Axboe3d6392c2007-07-09 12:38:05 +0200821 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900822 bcd = idr_find(&bsg_minor_idr, iminor(inode));
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900823 if (bcd)
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900824 kref_get(&bcd->ref);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200825 mutex_unlock(&bsg_mutex);
826
827 if (!bcd)
828 return ERR_PTR(-ENODEV);
829
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900830 bd = __bsg_get_device(iminor(inode), bcd->queue);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900831 if (bd)
832 return bd;
833
834 bd = bsg_add_device(inode, bcd->queue, file);
835 if (IS_ERR(bd))
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900836 kref_put(&bcd->ref, bsg_kref_release_function);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900837
838 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200839}
840
841static int bsg_open(struct inode *inode, struct file *file)
842{
Jonathan Corbet75bd2ef2008-05-15 09:09:23 -0600843 struct bsg_device *bd;
844
845 lock_kernel();
846 bd = bsg_get_device(inode, file);
847 unlock_kernel();
Jens Axboe3d6392c2007-07-09 12:38:05 +0200848
849 if (IS_ERR(bd))
850 return PTR_ERR(bd);
851
852 file->private_data = bd;
853 return 0;
854}
855
856static int bsg_release(struct inode *inode, struct file *file)
857{
858 struct bsg_device *bd = file->private_data;
859
860 file->private_data = NULL;
861 return bsg_put_device(bd);
862}
863
864static unsigned int bsg_poll(struct file *file, poll_table *wait)
865{
866 struct bsg_device *bd = file->private_data;
867 unsigned int mask = 0;
868
869 poll_wait(file, &bd->wq_done, wait);
870 poll_wait(file, &bd->wq_free, wait);
871
872 spin_lock_irq(&bd->lock);
873 if (!list_empty(&bd->done_list))
874 mask |= POLLIN | POLLRDNORM;
875 if (bd->queued_cmds >= bd->max_queue)
876 mask |= POLLOUT;
877 spin_unlock_irq(&bd->lock);
878
879 return mask;
880}
881
Jens Axboe25fd1642007-07-17 08:52:29 +0200882static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200883{
884 struct bsg_device *bd = file->private_data;
885 int __user *uarg = (int __user *) arg;
James Bottomley2d507a02007-12-29 10:59:53 -0600886 int ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200887
Jens Axboe3d6392c2007-07-09 12:38:05 +0200888 switch (cmd) {
889 /*
890 * our own ioctls
891 */
892 case SG_GET_COMMAND_Q:
893 return put_user(bd->max_queue, uarg);
Jens Axboe5309cb32007-01-23 16:24:41 +0100894 case SG_SET_COMMAND_Q: {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200895 int queue;
896
897 if (get_user(queue, uarg))
898 return -EFAULT;
Jens Axboe5309cb32007-01-23 16:24:41 +0100899 if (queue < 1)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200900 return -EINVAL;
901
Jens Axboe5309cb32007-01-23 16:24:41 +0100902 spin_lock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200903 bd->max_queue = queue;
Jens Axboe5309cb32007-01-23 16:24:41 +0100904 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200905 return 0;
906 }
907
908 /*
909 * SCSI/sg ioctls
910 */
911 case SG_GET_VERSION_NUM:
912 case SCSI_IOCTL_GET_IDLUN:
913 case SCSI_IOCTL_GET_BUS_NUMBER:
914 case SG_SET_TIMEOUT:
915 case SG_GET_TIMEOUT:
916 case SG_GET_RESERVED_SIZE:
917 case SG_SET_RESERVED_SIZE:
918 case SG_EMULATED_HOST:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200919 case SCSI_IOCTL_SEND_COMMAND: {
920 void __user *uarg = (void __user *) arg;
Al Viro74f3c8a2007-08-27 15:38:10 -0400921 return scsi_cmd_ioctl(bd->queue, NULL, file->f_mode, cmd, uarg);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200922 }
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100923 case SG_IO: {
924 struct request *rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200925 struct bio *bio, *bidi_bio = NULL;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100926 struct sg_io_v4 hdr;
Boaz Harroshc1c20122009-02-03 07:47:29 +0100927 u8 sense[SCSI_SENSE_BUFFERSIZE];
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100928
929 if (copy_from_user(&hdr, uarg, sizeof(hdr)))
930 return -EFAULT;
931
Boaz Harroshc1c20122009-02-03 07:47:29 +0100932 rq = bsg_map_hdr(bd, &hdr, file->f_mode & FMODE_WRITE, sense);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100933 if (IS_ERR(rq))
934 return PTR_ERR(rq);
935
936 bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200937 if (rq->next_rq)
938 bidi_bio = rq->next_rq->bio;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200939 blk_execute_rq(bd->queue, NULL, rq, 0);
James Bottomley2d507a02007-12-29 10:59:53 -0600940 ret = blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100941
942 if (copy_to_user(uarg, &hdr, sizeof(hdr)))
943 return -EFAULT;
Jens Axboeb711afa2006-12-20 11:25:23 +0100944
James Bottomley2d507a02007-12-29 10:59:53 -0600945 return ret;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100946 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200947 /*
948 * block device ioctls
949 */
950 default:
951#if 0
952 return ioctl_by_bdev(bd->bdev, cmd, arg);
953#else
954 return -ENOTTY;
955#endif
956 }
957}
958
Arjan van de Ven7344be02007-10-15 11:01:53 +0200959static const struct file_operations bsg_fops = {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200960 .read = bsg_read,
961 .write = bsg_write,
962 .poll = bsg_poll,
963 .open = bsg_open,
964 .release = bsg_release,
Jens Axboe25fd1642007-07-17 08:52:29 +0200965 .unlocked_ioctl = bsg_ioctl,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200966 .owner = THIS_MODULE,
967};
968
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200969void bsg_unregister_queue(struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200970{
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200971 struct bsg_class_device *bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200972
FUJITA Tomonoridf468822007-07-21 13:23:25 +0900973 if (!bcd->class_dev)
974 return;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200975
976 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900977 idr_remove(&bsg_minor_idr, bcd->minor);
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200978 sysfs_remove_link(&q->kobj, "bsg");
Tony Jonesee959b02008-02-22 00:13:36 +0100979 device_unregister(bcd->class_dev);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200980 bcd->class_dev = NULL;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900981 kref_put(&bcd->ref, bsg_kref_release_function);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200982 mutex_unlock(&bsg_mutex);
983}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +0200984EXPORT_SYMBOL_GPL(bsg_unregister_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200985
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900986int bsg_register_queue(struct request_queue *q, struct device *parent,
987 const char *name, void (*release)(struct device *))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200988{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900989 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200990 dev_t dev;
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900991 int ret, minor;
Tony Jonesee959b02008-02-22 00:13:36 +0100992 struct device *class_dev = NULL;
James Bottomley39dca552007-07-20 18:22:17 -0500993 const char *devname;
994
995 if (name)
996 devname = name;
997 else
Kay Sievers3ada8b72009-01-06 10:44:43 -0800998 devname = dev_name(parent);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200999
1000 /*
1001 * we need a proper transport to send commands, not a stacked device
1002 */
1003 if (!q->request_fn)
1004 return 0;
1005
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001006 bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001007 memset(bcd, 0, sizeof(*bcd));
Jens Axboe3d6392c2007-07-09 12:38:05 +02001008
1009 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001010
1011 ret = idr_pre_get(&bsg_minor_idr, GFP_KERNEL);
1012 if (!ret) {
1013 ret = -ENOMEM;
1014 goto unlock;
1015 }
1016
1017 ret = idr_get_new(&bsg_minor_idr, bcd, &minor);
1018 if (ret < 0)
1019 goto unlock;
1020
1021 if (minor >= BSG_MAX_DEVS) {
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001022 printk(KERN_ERR "bsg: too many bsg devices\n");
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001023 ret = -EINVAL;
1024 goto remove_idr;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001025 }
1026
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001027 bcd->minor = minor;
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001028 bcd->queue = q;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001029 bcd->parent = get_device(parent);
1030 bcd->release = release;
1031 kref_init(&bcd->ref);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001032 dev = MKDEV(bsg_major, bcd->minor);
Greg Kroah-Hartman1ff9f542008-07-21 20:03:34 -07001033 class_dev = device_create(bsg_class, parent, dev, NULL, "%s", devname);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001034 if (IS_ERR(class_dev)) {
1035 ret = PTR_ERR(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001036 goto put_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001037 }
1038 bcd->class_dev = class_dev;
1039
Linus Torvaldsabce8912007-07-16 11:18:23 -07001040 if (q->kobj.sd) {
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001041 ret = sysfs_create_link(&q->kobj, &bcd->class_dev->kobj, "bsg");
1042 if (ret)
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001043 goto unregister_class_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001044 }
1045
Jens Axboe3d6392c2007-07-09 12:38:05 +02001046 mutex_unlock(&bsg_mutex);
1047 return 0;
James Bottomley6826ee42007-07-20 16:50:10 -05001048
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001049unregister_class_dev:
Tony Jonesee959b02008-02-22 00:13:36 +01001050 device_unregister(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001051put_dev:
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001052 put_device(parent);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001053remove_idr:
1054 idr_remove(&bsg_minor_idr, minor);
1055unlock:
Jens Axboe264a0472007-01-23 16:30:17 +01001056 mutex_unlock(&bsg_mutex);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001057 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001058}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +02001059EXPORT_SYMBOL_GPL(bsg_register_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001060
Greg Kroah-Hartman7e7654a2007-09-12 15:06:57 -07001061static struct cdev bsg_cdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001062
Jens Axboe3d6392c2007-07-09 12:38:05 +02001063static int __init bsg_init(void)
1064{
1065 int ret, i;
Jens Axboe46f6ef42007-07-17 08:56:10 +02001066 dev_t devid;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001067
Jens Axboe5309cb32007-01-23 16:24:41 +01001068 bsg_cmd_cachep = kmem_cache_create("bsg_cmd",
Paul Mundt20c2df82007-07-20 10:11:58 +09001069 sizeof(struct bsg_command), 0, 0, NULL);
Jens Axboe5309cb32007-01-23 16:24:41 +01001070 if (!bsg_cmd_cachep) {
1071 printk(KERN_ERR "bsg: failed creating slab cache\n");
1072 return -ENOMEM;
1073 }
1074
Jens Axboe25fd1642007-07-17 08:52:29 +02001075 for (i = 0; i < BSG_LIST_ARRAY_SIZE; i++)
Jens Axboe3d6392c2007-07-09 12:38:05 +02001076 INIT_HLIST_HEAD(&bsg_device_list[i]);
1077
1078 bsg_class = class_create(THIS_MODULE, "bsg");
Jens Axboe5309cb32007-01-23 16:24:41 +01001079 if (IS_ERR(bsg_class)) {
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001080 ret = PTR_ERR(bsg_class);
1081 goto destroy_kmemcache;
Jens Axboe5309cb32007-01-23 16:24:41 +01001082 }
Jens Axboe3d6392c2007-07-09 12:38:05 +02001083
Jens Axboe46f6ef42007-07-17 08:56:10 +02001084 ret = alloc_chrdev_region(&devid, 0, BSG_MAX_DEVS, "bsg");
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001085 if (ret)
1086 goto destroy_bsg_class;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001087
Jens Axboe46f6ef42007-07-17 08:56:10 +02001088 bsg_major = MAJOR(devid);
1089
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001090 cdev_init(&bsg_cdev, &bsg_fops);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001091 ret = cdev_add(&bsg_cdev, MKDEV(bsg_major, 0), BSG_MAX_DEVS);
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001092 if (ret)
1093 goto unregister_chrdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001094
Jens Axboe5d3a8cd2007-07-17 15:10:09 +02001095 printk(KERN_INFO BSG_DESCRIPTION " version " BSG_VERSION
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001096 " loaded (major %d)\n", bsg_major);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001097 return 0;
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001098unregister_chrdev:
1099 unregister_chrdev_region(MKDEV(bsg_major, 0), BSG_MAX_DEVS);
1100destroy_bsg_class:
1101 class_destroy(bsg_class);
1102destroy_kmemcache:
1103 kmem_cache_destroy(bsg_cmd_cachep);
1104 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001105}
1106
1107MODULE_AUTHOR("Jens Axboe");
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001108MODULE_DESCRIPTION(BSG_DESCRIPTION);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001109MODULE_LICENSE("GPL");
1110
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001111device_initcall(bsg_init);