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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>
Randy Dunlapad5ebd22009-11-11 13:47:45 +010018#include <linux/jiffies.h>
Jens Axboe3d6392c2007-07-09 12:38:05 +020019#include <linux/percpu.h>
20#include <linux/uio.h>
FUJITA Tomonori598443a2007-07-23 09:33:26 +090021#include <linux/idr.h>
Jens Axboe3d6392c2007-07-09 12:38:05 +020022#include <linux/bsg.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090023#include <linux/slab.h>
Jens Axboe3d6392c2007-07-09 12:38:05 +020024
25#include <scsi/scsi.h>
26#include <scsi/scsi_ioctl.h>
27#include <scsi/scsi_cmnd.h>
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +020028#include <scsi/scsi_device.h>
29#include <scsi/scsi_driver.h>
Jens Axboe3d6392c2007-07-09 12:38:05 +020030#include <scsi/sg.h>
31
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +020032#define BSG_DESCRIPTION "Block layer SCSI generic (bsg) driver"
33#define BSG_VERSION "0.4"
Jens Axboe3d6392c2007-07-09 12:38:05 +020034
Jens Axboe3d6392c2007-07-09 12:38:05 +020035struct bsg_device {
Jens Axboe165125e2007-07-24 09:28:11 +020036 struct request_queue *queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +020037 spinlock_t lock;
38 struct list_head busy_list;
39 struct list_head done_list;
40 struct hlist_node dev_list;
41 atomic_t ref_count;
Jens Axboe3d6392c2007-07-09 12:38:05 +020042 int queued_cmds;
43 int done_cmds;
Jens Axboe3d6392c2007-07-09 12:38:05 +020044 wait_queue_head_t wq_done;
45 wait_queue_head_t wq_free;
Kay Sievers3ada8b72009-01-06 10:44:43 -080046 char name[20];
Jens Axboe3d6392c2007-07-09 12:38:05 +020047 int max_queue;
48 unsigned long flags;
49};
50
51enum {
52 BSG_F_BLOCK = 1,
Jens Axboe3d6392c2007-07-09 12:38:05 +020053};
54
Jens Axboe5309cb32007-01-23 16:24:41 +010055#define BSG_DEFAULT_CMDS 64
FUJITA Tomonori292b7f22007-03-28 13:29:58 +020056#define BSG_MAX_DEVS 32768
Jens Axboe3d6392c2007-07-09 12:38:05 +020057
58#undef BSG_DEBUG
59
60#ifdef BSG_DEBUG
Harvey Harrison24c03d42008-05-01 04:35:17 -070061#define dprintk(fmt, args...) printk(KERN_ERR "%s: " fmt, __func__, ##args)
Jens Axboe3d6392c2007-07-09 12:38:05 +020062#else
63#define dprintk(fmt, args...)
64#endif
65
Jens Axboe3d6392c2007-07-09 12:38:05 +020066static DEFINE_MUTEX(bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +090067static DEFINE_IDR(bsg_minor_idr);
Jens Axboe3d6392c2007-07-09 12:38:05 +020068
Jens Axboe25fd1642007-07-17 08:52:29 +020069#define BSG_LIST_ARRAY_SIZE 8
Jens Axboe25fd1642007-07-17 08:52:29 +020070static struct hlist_head bsg_device_list[BSG_LIST_ARRAY_SIZE];
Jens Axboe3d6392c2007-07-09 12:38:05 +020071
72static struct class *bsg_class;
Jens Axboe46f6ef42007-07-17 08:56:10 +020073static int bsg_major;
Jens Axboe3d6392c2007-07-09 12:38:05 +020074
Jens Axboe5309cb32007-01-23 16:24:41 +010075static struct kmem_cache *bsg_cmd_cachep;
76
Jens Axboe3d6392c2007-07-09 12:38:05 +020077/*
78 * our internal command type
79 */
80struct bsg_command {
81 struct bsg_device *bd;
82 struct list_head list;
83 struct request *rq;
84 struct bio *bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +020085 struct bio *bidi_bio;
Jens Axboe3d6392c2007-07-09 12:38:05 +020086 int err;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +010087 struct sg_io_v4 hdr;
Jens Axboe3d6392c2007-07-09 12:38:05 +020088 char sense[SCSI_SENSE_BUFFERSIZE];
89};
90
91static void bsg_free_command(struct bsg_command *bc)
92{
93 struct bsg_device *bd = bc->bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +020094 unsigned long flags;
95
Jens Axboe5309cb32007-01-23 16:24:41 +010096 kmem_cache_free(bsg_cmd_cachep, bc);
Jens Axboe3d6392c2007-07-09 12:38:05 +020097
98 spin_lock_irqsave(&bd->lock, flags);
99 bd->queued_cmds--;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200100 spin_unlock_irqrestore(&bd->lock, flags);
101
102 wake_up(&bd->wq_free);
103}
104
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200105static struct bsg_command *bsg_alloc_command(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200106{
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200107 struct bsg_command *bc = ERR_PTR(-EINVAL);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200108
109 spin_lock_irq(&bd->lock);
110
111 if (bd->queued_cmds >= bd->max_queue)
112 goto out;
113
Jens Axboe3d6392c2007-07-09 12:38:05 +0200114 bd->queued_cmds++;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200115 spin_unlock_irq(&bd->lock);
116
Jens Axboe25fd1642007-07-17 08:52:29 +0200117 bc = kmem_cache_zalloc(bsg_cmd_cachep, GFP_KERNEL);
Jens Axboe5309cb32007-01-23 16:24:41 +0100118 if (unlikely(!bc)) {
119 spin_lock_irq(&bd->lock);
FUJITA Tomonori7e75d732007-01-24 09:05:54 +0100120 bd->queued_cmds--;
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200121 bc = ERR_PTR(-ENOMEM);
FUJITA Tomonori7e75d732007-01-24 09:05:54 +0100122 goto out;
Jens Axboe5309cb32007-01-23 16:24:41 +0100123 }
124
Jens Axboe3d6392c2007-07-09 12:38:05 +0200125 bc->bd = bd;
126 INIT_LIST_HEAD(&bc->list);
Jens Axboe5309cb32007-01-23 16:24:41 +0100127 dprintk("%s: returning free cmd %p\n", bd->name, bc);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200128 return bc;
129out:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200130 spin_unlock_irq(&bd->lock);
131 return bc;
132}
133
FUJITA Tomonori1c1133e2007-07-17 12:21:15 +0200134static inline struct hlist_head *bsg_dev_idx_hash(int index)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200135{
FUJITA Tomonori1c1133e2007-07-17 12:21:15 +0200136 return &bsg_device_list[index & (BSG_LIST_ARRAY_SIZE - 1)];
Jens Axboe3d6392c2007-07-09 12:38:05 +0200137}
138
Jens Axboe25fd1642007-07-17 08:52:29 +0200139static int bsg_io_schedule(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200140{
141 DEFINE_WAIT(wait);
142 int ret = 0;
143
144 spin_lock_irq(&bd->lock);
145
146 BUG_ON(bd->done_cmds > bd->queued_cmds);
147
148 /*
149 * -ENOSPC or -ENODATA? I'm going for -ENODATA, meaning "I have no
150 * work to do", even though we return -ENOSPC after this same test
151 * during bsg_write() -- there, it means our buffer can't have more
152 * bsg_commands added to it, thus has no space left.
153 */
154 if (bd->done_cmds == bd->queued_cmds) {
155 ret = -ENODATA;
156 goto unlock;
157 }
158
159 if (!test_bit(BSG_F_BLOCK, &bd->flags)) {
160 ret = -EAGAIN;
161 goto unlock;
162 }
163
Jens Axboe25fd1642007-07-17 08:52:29 +0200164 prepare_to_wait(&bd->wq_done, &wait, TASK_UNINTERRUPTIBLE);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200165 spin_unlock_irq(&bd->lock);
166 io_schedule();
167 finish_wait(&bd->wq_done, &wait);
168
Jens Axboe3d6392c2007-07-09 12:38:05 +0200169 return ret;
170unlock:
171 spin_unlock_irq(&bd->lock);
172 return ret;
173}
174
Jens Axboe165125e2007-07-24 09:28:11 +0200175static int blk_fill_sgv4_hdr_rq(struct request_queue *q, struct request *rq,
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900176 struct sg_io_v4 *hdr, struct bsg_device *bd,
Al Viroaeb5d722008-09-02 15:28:45 -0400177 fmode_t has_write_perm)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200178{
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900179 if (hdr->request_len > BLK_MAX_CDB) {
180 rq->cmd = kzalloc(hdr->request_len, GFP_KERNEL);
181 if (!rq->cmd)
182 return -ENOMEM;
183 }
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100184
185 if (copy_from_user(rq->cmd, (void *)(unsigned long)hdr->request,
186 hdr->request_len))
187 return -EFAULT;
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200188
189 if (hdr->subprotocol == BSG_SUB_PROTOCOL_SCSI_CMD) {
Jens Axboe018e0442009-06-26 16:27:10 +0200190 if (blk_verify_command(rq->cmd, has_write_perm))
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200191 return -EPERM;
192 } else if (!capable(CAP_SYS_RAWIO))
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100193 return -EPERM;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200194
195 /*
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100196 * fill in request structure
Jens Axboe3d6392c2007-07-09 12:38:05 +0200197 */
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100198 rq->cmd_len = hdr->request_len;
199 rq->cmd_type = REQ_TYPE_BLOCK_PC;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200200
Randy Dunlapad5ebd22009-11-11 13:47:45 +0100201 rq->timeout = msecs_to_jiffies(hdr->timeout);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100202 if (!rq->timeout)
203 rq->timeout = q->sg_timeout;
204 if (!rq->timeout)
205 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
Linus Torvaldsf2f1fa72008-12-05 14:49:18 -0800206 if (rq->timeout < BLK_MIN_SG_TIMEOUT)
207 rq->timeout = BLK_MIN_SG_TIMEOUT;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200208
209 return 0;
210}
211
212/*
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100213 * Check if sg_io_v4 from user is allowed and valid
214 */
215static int
Jens Axboe165125e2007-07-24 09:28:11 +0200216bsg_validate_sgv4_hdr(struct request_queue *q, struct sg_io_v4 *hdr, int *rw)
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100217{
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200218 int ret = 0;
219
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100220 if (hdr->guard != 'Q')
221 return -EINVAL;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100222
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200223 switch (hdr->protocol) {
224 case BSG_PROTOCOL_SCSI:
225 switch (hdr->subprotocol) {
226 case BSG_SUB_PROTOCOL_SCSI_CMD:
227 case BSG_SUB_PROTOCOL_SCSI_TRANSPORT:
228 break;
229 default:
230 ret = -EINVAL;
231 }
232 break;
233 default:
234 ret = -EINVAL;
235 }
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100236
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100237 *rw = hdr->dout_xfer_len ? WRITE : READ;
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200238 return ret;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100239}
240
241/*
242 * map sg_io_v4 to a request.
Jens Axboe3d6392c2007-07-09 12:38:05 +0200243 */
244static struct request *
Boaz Harroshc1c201202009-02-03 07:47:29 +0100245bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t has_write_perm,
246 u8 *sense)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200247{
Jens Axboe165125e2007-07-24 09:28:11 +0200248 struct request_queue *q = bd->queue;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200249 struct request *rq, *next_rq = NULL;
Jens Axboe25fd1642007-07-17 08:52:29 +0200250 int ret, rw;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100251 unsigned int dxfer_len;
252 void *dxferp = NULL;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200253
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100254 dprintk("map hdr %llx/%u %llx/%u\n", (unsigned long long) hdr->dout_xferp,
255 hdr->dout_xfer_len, (unsigned long long) hdr->din_xferp,
256 hdr->din_xfer_len);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200257
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100258 ret = bsg_validate_sgv4_hdr(q, hdr, &rw);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200259 if (ret)
260 return ERR_PTR(ret);
261
262 /*
Daniel Mack3ad2f3f2010-02-03 08:01:28 +0800263 * map scatter-gather elements separately and string them to request
Jens Axboe3d6392c2007-07-09 12:38:05 +0200264 */
265 rq = blk_get_request(q, rw, GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200266 if (!rq)
267 return ERR_PTR(-ENOMEM);
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900268 ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, bd, has_write_perm);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200269 if (ret)
270 goto out;
271
272 if (rw == WRITE && hdr->din_xfer_len) {
273 if (!test_bit(QUEUE_FLAG_BIDI, &q->queue_flags)) {
274 ret = -EOPNOTSUPP;
275 goto out;
276 }
277
278 next_rq = blk_get_request(q, READ, GFP_KERNEL);
279 if (!next_rq) {
280 ret = -ENOMEM;
281 goto out;
282 }
283 rq->next_rq = next_rq;
James Bottomley40f62022008-01-25 20:05:55 -0600284 next_rq->cmd_type = rq->cmd_type;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200285
286 dxferp = (void*)(unsigned long)hdr->din_xferp;
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900287 ret = blk_rq_map_user(q, next_rq, NULL, dxferp,
288 hdr->din_xfer_len, GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200289 if (ret)
290 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200291 }
292
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100293 if (hdr->dout_xfer_len) {
294 dxfer_len = hdr->dout_xfer_len;
295 dxferp = (void*)(unsigned long)hdr->dout_xferp;
296 } else if (hdr->din_xfer_len) {
297 dxfer_len = hdr->din_xfer_len;
298 dxferp = (void*)(unsigned long)hdr->din_xferp;
299 } else
300 dxfer_len = 0;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200301
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100302 if (dxfer_len) {
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900303 ret = blk_rq_map_user(q, rq, NULL, dxferp, dxfer_len,
304 GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200305 if (ret)
306 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200307 }
Boaz Harroshc1c201202009-02-03 07:47:29 +0100308
309 rq->sense = sense;
310 rq->sense_len = 0;
311
Jens Axboe3d6392c2007-07-09 12:38:05 +0200312 return rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200313out:
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900314 if (rq->cmd != rq->__cmd)
315 kfree(rq->cmd);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200316 blk_put_request(rq);
317 if (next_rq) {
318 blk_rq_unmap_user(next_rq->bio);
319 blk_put_request(next_rq);
320 }
321 return ERR_PTR(ret);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200322}
323
324/*
325 * async completion call-back from the block layer, when scsi/ide/whatever
326 * calls end_that_request_last() on a request
327 */
328static void bsg_rq_end_io(struct request *rq, int uptodate)
329{
330 struct bsg_command *bc = rq->end_io_data;
331 struct bsg_device *bd = bc->bd;
332 unsigned long flags;
333
Jens Axboe5309cb32007-01-23 16:24:41 +0100334 dprintk("%s: finished rq %p bc %p, bio %p stat %d\n",
335 bd->name, rq, bc, bc->bio, uptodate);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200336
337 bc->hdr.duration = jiffies_to_msecs(jiffies - bc->hdr.duration);
338
339 spin_lock_irqsave(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200340 list_move_tail(&bc->list, &bd->done_list);
341 bd->done_cmds++;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200342 spin_unlock_irqrestore(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200343
344 wake_up(&bd->wq_done);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200345}
346
347/*
348 * do final setup of a 'bc' and submit the matching 'rq' to the block
349 * layer for io
350 */
Jens Axboe165125e2007-07-24 09:28:11 +0200351static void bsg_add_command(struct bsg_device *bd, struct request_queue *q,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200352 struct bsg_command *bc, struct request *rq)
353{
Boaz Harrosh05378942009-03-24 12:23:40 +0100354 int at_head = (0 == (bc->hdr.flags & BSG_FLAG_Q_AT_TAIL));
355
Jens Axboe3d6392c2007-07-09 12:38:05 +0200356 /*
357 * add bc command to busy queue and submit rq for io
358 */
359 bc->rq = rq;
360 bc->bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200361 if (rq->next_rq)
362 bc->bidi_bio = rq->next_rq->bio;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200363 bc->hdr.duration = jiffies;
364 spin_lock_irq(&bd->lock);
365 list_add_tail(&bc->list, &bd->busy_list);
366 spin_unlock_irq(&bd->lock);
367
368 dprintk("%s: queueing rq %p, bc %p\n", bd->name, rq, bc);
369
370 rq->end_io_data = bc;
Boaz Harrosh05378942009-03-24 12:23:40 +0100371 blk_execute_rq_nowait(q, NULL, rq, at_head, bsg_rq_end_io);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200372}
373
Jens Axboe25fd1642007-07-17 08:52:29 +0200374static struct bsg_command *bsg_next_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200375{
376 struct bsg_command *bc = NULL;
377
378 spin_lock_irq(&bd->lock);
379 if (bd->done_cmds) {
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900380 bc = list_first_entry(&bd->done_list, struct bsg_command, list);
Jens Axboe25fd1642007-07-17 08:52:29 +0200381 list_del(&bc->list);
382 bd->done_cmds--;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200383 }
384 spin_unlock_irq(&bd->lock);
385
386 return bc;
387}
388
389/*
390 * Get a finished command from the done list
391 */
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200392static struct bsg_command *bsg_get_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200393{
394 struct bsg_command *bc;
395 int ret;
396
397 do {
398 bc = bsg_next_done_cmd(bd);
399 if (bc)
400 break;
401
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200402 if (!test_bit(BSG_F_BLOCK, &bd->flags)) {
403 bc = ERR_PTR(-EAGAIN);
404 break;
405 }
406
407 ret = wait_event_interruptible(bd->wq_done, bd->done_cmds);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200408 if (ret) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200409 bc = ERR_PTR(-ERESTARTSYS);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200410 break;
411 }
412 } while (1);
413
414 dprintk("%s: returning done %p\n", bd->name, bc);
415
416 return bc;
417}
418
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100419static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr,
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200420 struct bio *bio, struct bio *bidi_bio)
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100421{
422 int ret = 0;
423
Boaz Harroshc1c201202009-02-03 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 */
FUJITA Tomonori47897162010-09-17 00:46:42 +0900428 hdr->device_status = rq->errors & 0xff;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100429 hdr->transport_status = host_byte(rq->errors);
430 hdr->driver_status = driver_byte(rq->errors);
431 hdr->info = 0;
432 if (hdr->device_status || hdr->transport_status || hdr->driver_status)
433 hdr->info |= SG_INFO_CHECK;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100434 hdr->response_len = 0;
435
436 if (rq->sense_len && hdr->response) {
Jens Axboe25fd1642007-07-17 08:52:29 +0200437 int len = min_t(unsigned int, hdr->max_response_len,
438 rq->sense_len);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100439
440 ret = copy_to_user((void*)(unsigned long)hdr->response,
441 rq->sense, len);
442 if (!ret)
443 hdr->response_len = len;
444 else
445 ret = -EFAULT;
446 }
447
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200448 if (rq->next_rq) {
Tejun Heoc3a4d782009-05-07 22:24:37 +0900449 hdr->dout_resid = rq->resid_len;
450 hdr->din_resid = rq->next_rq->resid_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200451 blk_rq_unmap_user(bidi_bio);
452 blk_put_request(rq->next_rq);
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900453 } else if (rq_data_dir(rq) == READ)
Tejun Heoc3a4d782009-05-07 22:24:37 +0900454 hdr->din_resid = rq->resid_len;
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900455 else
Tejun Heoc3a4d782009-05-07 22:24:37 +0900456 hdr->dout_resid = rq->resid_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 Harroshc1c201202009-02-03 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
Jonathan Corbet75bd2ef2008-05-15 09:09:23 -0600845 bd = bsg_get_device(inode, file);
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;
Boaz Harrosh05378942009-03-24 12:23:40 +0100925 int at_head;
Boaz Harroshc1c201202009-02-03 07:47:29 +0100926 u8 sense[SCSI_SENSE_BUFFERSIZE];
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100927
928 if (copy_from_user(&hdr, uarg, sizeof(hdr)))
929 return -EFAULT;
930
Boaz Harroshc1c201202009-02-03 07:47:29 +0100931 rq = bsg_map_hdr(bd, &hdr, file->f_mode & FMODE_WRITE, sense);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100932 if (IS_ERR(rq))
933 return PTR_ERR(rq);
934
935 bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200936 if (rq->next_rq)
937 bidi_bio = rq->next_rq->bio;
Boaz Harrosh05378942009-03-24 12:23:40 +0100938
939 at_head = (0 == (hdr.flags & BSG_FLAG_Q_AT_TAIL));
940 blk_execute_rq(bd->queue, NULL, rq, at_head);
James Bottomley2d507a02007-12-29 10:59:53 -0600941 ret = blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100942
943 if (copy_to_user(uarg, &hdr, sizeof(hdr)))
944 return -EFAULT;
Jens Axboeb711afa2006-12-20 11:25:23 +0100945
James Bottomley2d507a02007-12-29 10:59:53 -0600946 return ret;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100947 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200948 /*
949 * block device ioctls
950 */
951 default:
952#if 0
953 return ioctl_by_bdev(bd->bdev, cmd, arg);
954#else
955 return -ENOTTY;
956#endif
957 }
958}
959
Arjan van de Ven7344be02007-10-15 11:01:53 +0200960static const struct file_operations bsg_fops = {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200961 .read = bsg_read,
962 .write = bsg_write,
963 .poll = bsg_poll,
964 .open = bsg_open,
965 .release = bsg_release,
Jens Axboe25fd1642007-07-17 08:52:29 +0200966 .unlocked_ioctl = bsg_ioctl,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200967 .owner = THIS_MODULE,
Arnd Bergmann6038f372010-08-15 18:52:59 +0200968 .llseek = default_llseek,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200969};
970
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200971void bsg_unregister_queue(struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200972{
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200973 struct bsg_class_device *bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200974
FUJITA Tomonoridf468822007-07-21 13:23:25 +0900975 if (!bcd->class_dev)
976 return;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200977
978 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900979 idr_remove(&bsg_minor_idr, bcd->minor);
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200980 sysfs_remove_link(&q->kobj, "bsg");
Tony Jonesee959b02008-02-22 00:13:36 +0100981 device_unregister(bcd->class_dev);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200982 bcd->class_dev = NULL;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900983 kref_put(&bcd->ref, bsg_kref_release_function);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200984 mutex_unlock(&bsg_mutex);
985}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +0200986EXPORT_SYMBOL_GPL(bsg_unregister_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200987
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900988int bsg_register_queue(struct request_queue *q, struct device *parent,
989 const char *name, void (*release)(struct device *))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200990{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900991 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200992 dev_t dev;
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900993 int ret, minor;
Tony Jonesee959b02008-02-22 00:13:36 +0100994 struct device *class_dev = NULL;
James Bottomley39dca552007-07-20 18:22:17 -0500995 const char *devname;
996
997 if (name)
998 devname = name;
999 else
Kay Sievers3ada8b72009-01-06 10:44:43 -08001000 devname = dev_name(parent);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001001
1002 /*
1003 * we need a proper transport to send commands, not a stacked device
1004 */
1005 if (!q->request_fn)
1006 return 0;
1007
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001008 bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001009 memset(bcd, 0, sizeof(*bcd));
Jens Axboe3d6392c2007-07-09 12:38:05 +02001010
1011 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001012
1013 ret = idr_pre_get(&bsg_minor_idr, GFP_KERNEL);
1014 if (!ret) {
1015 ret = -ENOMEM;
1016 goto unlock;
1017 }
1018
1019 ret = idr_get_new(&bsg_minor_idr, bcd, &minor);
1020 if (ret < 0)
1021 goto unlock;
1022
1023 if (minor >= BSG_MAX_DEVS) {
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001024 printk(KERN_ERR "bsg: too many bsg devices\n");
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001025 ret = -EINVAL;
1026 goto remove_idr;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001027 }
1028
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001029 bcd->minor = minor;
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001030 bcd->queue = q;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001031 bcd->parent = get_device(parent);
1032 bcd->release = release;
1033 kref_init(&bcd->ref);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001034 dev = MKDEV(bsg_major, bcd->minor);
Greg Kroah-Hartman1ff9f542008-07-21 20:03:34 -07001035 class_dev = device_create(bsg_class, parent, dev, NULL, "%s", devname);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001036 if (IS_ERR(class_dev)) {
1037 ret = PTR_ERR(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001038 goto put_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001039 }
1040 bcd->class_dev = class_dev;
1041
Linus Torvaldsabce8912007-07-16 11:18:23 -07001042 if (q->kobj.sd) {
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001043 ret = sysfs_create_link(&q->kobj, &bcd->class_dev->kobj, "bsg");
1044 if (ret)
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001045 goto unregister_class_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001046 }
1047
Jens Axboe3d6392c2007-07-09 12:38:05 +02001048 mutex_unlock(&bsg_mutex);
1049 return 0;
James Bottomley6826ee42007-07-20 16:50:10 -05001050
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001051unregister_class_dev:
Tony Jonesee959b02008-02-22 00:13:36 +01001052 device_unregister(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001053put_dev:
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001054 put_device(parent);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001055remove_idr:
1056 idr_remove(&bsg_minor_idr, minor);
1057unlock:
Jens Axboe264a0472007-01-23 16:30:17 +01001058 mutex_unlock(&bsg_mutex);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001059 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001060}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +02001061EXPORT_SYMBOL_GPL(bsg_register_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001062
Greg Kroah-Hartman7e7654a2007-09-12 15:06:57 -07001063static struct cdev bsg_cdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001064
Kay Sieverse454cea2009-09-18 23:01:12 +02001065static char *bsg_devnode(struct device *dev, mode_t *mode)
Kay Sievers2bdf9142009-04-30 15:23:42 +02001066{
1067 return kasprintf(GFP_KERNEL, "bsg/%s", dev_name(dev));
1068}
1069
Jens Axboe3d6392c2007-07-09 12:38:05 +02001070static int __init bsg_init(void)
1071{
1072 int ret, i;
Jens Axboe46f6ef42007-07-17 08:56:10 +02001073 dev_t devid;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001074
Jens Axboe5309cb32007-01-23 16:24:41 +01001075 bsg_cmd_cachep = kmem_cache_create("bsg_cmd",
Paul Mundt20c2df82007-07-20 10:11:58 +09001076 sizeof(struct bsg_command), 0, 0, NULL);
Jens Axboe5309cb32007-01-23 16:24:41 +01001077 if (!bsg_cmd_cachep) {
1078 printk(KERN_ERR "bsg: failed creating slab cache\n");
1079 return -ENOMEM;
1080 }
1081
Jens Axboe25fd1642007-07-17 08:52:29 +02001082 for (i = 0; i < BSG_LIST_ARRAY_SIZE; i++)
Jens Axboe3d6392c2007-07-09 12:38:05 +02001083 INIT_HLIST_HEAD(&bsg_device_list[i]);
1084
1085 bsg_class = class_create(THIS_MODULE, "bsg");
Jens Axboe5309cb32007-01-23 16:24:41 +01001086 if (IS_ERR(bsg_class)) {
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001087 ret = PTR_ERR(bsg_class);
1088 goto destroy_kmemcache;
Jens Axboe5309cb32007-01-23 16:24:41 +01001089 }
Kay Sieverse454cea2009-09-18 23:01:12 +02001090 bsg_class->devnode = bsg_devnode;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001091
Jens Axboe46f6ef42007-07-17 08:56:10 +02001092 ret = alloc_chrdev_region(&devid, 0, BSG_MAX_DEVS, "bsg");
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001093 if (ret)
1094 goto destroy_bsg_class;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001095
Jens Axboe46f6ef42007-07-17 08:56:10 +02001096 bsg_major = MAJOR(devid);
1097
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001098 cdev_init(&bsg_cdev, &bsg_fops);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001099 ret = cdev_add(&bsg_cdev, MKDEV(bsg_major, 0), BSG_MAX_DEVS);
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001100 if (ret)
1101 goto unregister_chrdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001102
Jens Axboe5d3a8cd2007-07-17 15:10:09 +02001103 printk(KERN_INFO BSG_DESCRIPTION " version " BSG_VERSION
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001104 " loaded (major %d)\n", bsg_major);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001105 return 0;
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001106unregister_chrdev:
1107 unregister_chrdev_region(MKDEV(bsg_major, 0), BSG_MAX_DEVS);
1108destroy_bsg_class:
1109 class_destroy(bsg_class);
1110destroy_kmemcache:
1111 kmem_cache_destroy(bsg_cmd_cachep);
1112 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001113}
1114
1115MODULE_AUTHOR("Jens Axboe");
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001116MODULE_DESCRIPTION(BSG_DESCRIPTION);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001117MODULE_LICENSE("GPL");
1118
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001119device_initcall(bsg_init);