blob: b9a53615bdef4945748057e5efbfef56c5cb4847 [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>
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 Axboe165125e2007-07-24 09:28:11 +0200139static int blk_fill_sgv4_hdr_rq(struct request_queue *q, struct request *rq,
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900140 struct sg_io_v4 *hdr, struct bsg_device *bd,
Al Viroaeb5d722008-09-02 15:28:45 -0400141 fmode_t has_write_perm)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200142{
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900143 if (hdr->request_len > BLK_MAX_CDB) {
144 rq->cmd = kzalloc(hdr->request_len, GFP_KERNEL);
145 if (!rq->cmd)
146 return -ENOMEM;
147 }
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100148
Namhyung Kim2b727c62011-06-20 13:27:45 +0200149 if (copy_from_user(rq->cmd, (void __user *)(unsigned long)hdr->request,
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100150 hdr->request_len))
151 return -EFAULT;
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200152
153 if (hdr->subprotocol == BSG_SUB_PROTOCOL_SCSI_CMD) {
Jens Axboe018e0442009-06-26 16:27:10 +0200154 if (blk_verify_command(rq->cmd, has_write_perm))
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200155 return -EPERM;
156 } else if (!capable(CAP_SYS_RAWIO))
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100157 return -EPERM;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200158
159 /*
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100160 * fill in request structure
Jens Axboe3d6392c2007-07-09 12:38:05 +0200161 */
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100162 rq->cmd_len = hdr->request_len;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200163
Randy Dunlapad5ebd22009-11-11 13:47:45 +0100164 rq->timeout = msecs_to_jiffies(hdr->timeout);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100165 if (!rq->timeout)
166 rq->timeout = q->sg_timeout;
167 if (!rq->timeout)
168 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
Linus Torvaldsf2f1fa72008-12-05 14:49:18 -0800169 if (rq->timeout < BLK_MIN_SG_TIMEOUT)
170 rq->timeout = BLK_MIN_SG_TIMEOUT;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200171
172 return 0;
173}
174
175/*
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100176 * Check if sg_io_v4 from user is allowed and valid
177 */
178static int
Jens Axboe165125e2007-07-24 09:28:11 +0200179bsg_validate_sgv4_hdr(struct request_queue *q, struct sg_io_v4 *hdr, int *rw)
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100180{
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200181 int ret = 0;
182
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100183 if (hdr->guard != 'Q')
184 return -EINVAL;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100185
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200186 switch (hdr->protocol) {
187 case BSG_PROTOCOL_SCSI:
188 switch (hdr->subprotocol) {
189 case BSG_SUB_PROTOCOL_SCSI_CMD:
190 case BSG_SUB_PROTOCOL_SCSI_TRANSPORT:
191 break;
192 default:
193 ret = -EINVAL;
194 }
195 break;
196 default:
197 ret = -EINVAL;
198 }
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100199
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100200 *rw = hdr->dout_xfer_len ? WRITE : READ;
FUJITA Tomonori15d10b62007-07-16 08:52:16 +0200201 return ret;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100202}
203
204/*
205 * map sg_io_v4 to a request.
Jens Axboe3d6392c2007-07-09 12:38:05 +0200206 */
207static struct request *
Boaz Harroshc1c201202009-02-03 07:47:29 +0100208bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t has_write_perm,
209 u8 *sense)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200210{
Jens Axboe165125e2007-07-24 09:28:11 +0200211 struct request_queue *q = bd->queue;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200212 struct request *rq, *next_rq = NULL;
Jens Axboe25fd1642007-07-17 08:52:29 +0200213 int ret, rw;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100214 unsigned int dxfer_len;
Namhyung Kim2b727c62011-06-20 13:27:45 +0200215 void __user *dxferp = NULL;
James Smartc7a841f2010-11-14 11:12:04 -0500216 struct bsg_class_device *bcd = &q->bsg_dev;
217
218 /* if the LLD has been removed then the bsg_unregister_queue will
219 * eventually be called and the class_dev was freed, so we can no
220 * longer use this request_queue. Return no such address.
221 */
222 if (!bcd->class_dev)
223 return ERR_PTR(-ENXIO);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200224
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100225 dprintk("map hdr %llx/%u %llx/%u\n", (unsigned long long) hdr->dout_xferp,
226 hdr->dout_xfer_len, (unsigned long long) hdr->din_xferp,
227 hdr->din_xfer_len);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200228
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100229 ret = bsg_validate_sgv4_hdr(q, hdr, &rw);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200230 if (ret)
231 return ERR_PTR(ret);
232
233 /*
Daniel Mack3ad2f3f2010-02-03 08:01:28 +0800234 * map scatter-gather elements separately and string them to request
Jens Axboe3d6392c2007-07-09 12:38:05 +0200235 */
236 rq = blk_get_request(q, rw, GFP_KERNEL);
Joe Lawrencea492f072014-08-28 08:15:21 -0600237 if (IS_ERR(rq))
238 return rq;
Jens Axboef27b0872014-06-06 07:57:37 -0600239 blk_rq_set_block_pc(rq);
240
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900241 ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, bd, has_write_perm);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200242 if (ret)
243 goto out;
244
245 if (rw == WRITE && hdr->din_xfer_len) {
246 if (!test_bit(QUEUE_FLAG_BIDI, &q->queue_flags)) {
247 ret = -EOPNOTSUPP;
248 goto out;
249 }
250
251 next_rq = blk_get_request(q, READ, GFP_KERNEL);
Joe Lawrencea492f072014-08-28 08:15:21 -0600252 if (IS_ERR(next_rq)) {
253 ret = PTR_ERR(next_rq);
Jens Axboe55872c52014-08-28 15:05:40 -0600254 next_rq = NULL;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200255 goto out;
256 }
257 rq->next_rq = next_rq;
James Bottomley40f62022008-01-25 20:05:55 -0600258 next_rq->cmd_type = rq->cmd_type;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200259
Namhyung Kim2b727c62011-06-20 13:27:45 +0200260 dxferp = (void __user *)(unsigned long)hdr->din_xferp;
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900261 ret = blk_rq_map_user(q, next_rq, NULL, dxferp,
262 hdr->din_xfer_len, GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200263 if (ret)
264 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200265 }
266
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100267 if (hdr->dout_xfer_len) {
268 dxfer_len = hdr->dout_xfer_len;
Namhyung Kim2b727c62011-06-20 13:27:45 +0200269 dxferp = (void __user *)(unsigned long)hdr->dout_xferp;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100270 } else if (hdr->din_xfer_len) {
271 dxfer_len = hdr->din_xfer_len;
Namhyung Kim2b727c62011-06-20 13:27:45 +0200272 dxferp = (void __user *)(unsigned long)hdr->din_xferp;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100273 } else
274 dxfer_len = 0;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200275
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100276 if (dxfer_len) {
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900277 ret = blk_rq_map_user(q, rq, NULL, dxferp, dxfer_len,
278 GFP_KERNEL);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200279 if (ret)
280 goto out;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200281 }
Boaz Harroshc1c201202009-02-03 07:47:29 +0100282
283 rq->sense = sense;
284 rq->sense_len = 0;
285
Jens Axboe3d6392c2007-07-09 12:38:05 +0200286 return rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200287out:
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900288 if (rq->cmd != rq->__cmd)
289 kfree(rq->cmd);
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200290 blk_put_request(rq);
291 if (next_rq) {
292 blk_rq_unmap_user(next_rq->bio);
293 blk_put_request(next_rq);
294 }
295 return ERR_PTR(ret);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200296}
297
298/*
299 * async completion call-back from the block layer, when scsi/ide/whatever
300 * calls end_that_request_last() on a request
301 */
302static void bsg_rq_end_io(struct request *rq, int uptodate)
303{
304 struct bsg_command *bc = rq->end_io_data;
305 struct bsg_device *bd = bc->bd;
306 unsigned long flags;
307
Jens Axboe5309cb32007-01-23 16:24:41 +0100308 dprintk("%s: finished rq %p bc %p, bio %p stat %d\n",
309 bd->name, rq, bc, bc->bio, uptodate);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200310
311 bc->hdr.duration = jiffies_to_msecs(jiffies - bc->hdr.duration);
312
313 spin_lock_irqsave(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200314 list_move_tail(&bc->list, &bd->done_list);
315 bd->done_cmds++;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200316 spin_unlock_irqrestore(&bd->lock, flags);
Jens Axboe25fd1642007-07-17 08:52:29 +0200317
318 wake_up(&bd->wq_done);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200319}
320
321/*
322 * do final setup of a 'bc' and submit the matching 'rq' to the block
323 * layer for io
324 */
Jens Axboe165125e2007-07-24 09:28:11 +0200325static void bsg_add_command(struct bsg_device *bd, struct request_queue *q,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200326 struct bsg_command *bc, struct request *rq)
327{
Boaz Harrosh05378942009-03-24 12:23:40 +0100328 int at_head = (0 == (bc->hdr.flags & BSG_FLAG_Q_AT_TAIL));
329
Jens Axboe3d6392c2007-07-09 12:38:05 +0200330 /*
331 * add bc command to busy queue and submit rq for io
332 */
333 bc->rq = rq;
334 bc->bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200335 if (rq->next_rq)
336 bc->bidi_bio = rq->next_rq->bio;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200337 bc->hdr.duration = jiffies;
338 spin_lock_irq(&bd->lock);
339 list_add_tail(&bc->list, &bd->busy_list);
340 spin_unlock_irq(&bd->lock);
341
342 dprintk("%s: queueing rq %p, bc %p\n", bd->name, rq, bc);
343
344 rq->end_io_data = bc;
Boaz Harrosh05378942009-03-24 12:23:40 +0100345 blk_execute_rq_nowait(q, NULL, rq, at_head, bsg_rq_end_io);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200346}
347
Jens Axboe25fd1642007-07-17 08:52:29 +0200348static struct bsg_command *bsg_next_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200349{
350 struct bsg_command *bc = NULL;
351
352 spin_lock_irq(&bd->lock);
353 if (bd->done_cmds) {
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900354 bc = list_first_entry(&bd->done_list, struct bsg_command, list);
Jens Axboe25fd1642007-07-17 08:52:29 +0200355 list_del(&bc->list);
356 bd->done_cmds--;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200357 }
358 spin_unlock_irq(&bd->lock);
359
360 return bc;
361}
362
363/*
364 * Get a finished command from the done list
365 */
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200366static struct bsg_command *bsg_get_done_cmd(struct bsg_device *bd)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200367{
368 struct bsg_command *bc;
369 int ret;
370
371 do {
372 bc = bsg_next_done_cmd(bd);
373 if (bc)
374 break;
375
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200376 if (!test_bit(BSG_F_BLOCK, &bd->flags)) {
377 bc = ERR_PTR(-EAGAIN);
378 break;
379 }
380
381 ret = wait_event_interruptible(bd->wq_done, bd->done_cmds);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200382 if (ret) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200383 bc = ERR_PTR(-ERESTARTSYS);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200384 break;
385 }
386 } while (1);
387
388 dprintk("%s: returning done %p\n", bd->name, bc);
389
390 return bc;
391}
392
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100393static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr,
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200394 struct bio *bio, struct bio *bidi_bio)
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100395{
396 int ret = 0;
397
Boaz Harroshc1c201202009-02-03 07:47:29 +0100398 dprintk("rq %p bio %p 0x%x\n", rq, bio, rq->errors);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100399 /*
400 * fill in all the output members
401 */
FUJITA Tomonori47897162010-09-17 00:46:42 +0900402 hdr->device_status = rq->errors & 0xff;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100403 hdr->transport_status = host_byte(rq->errors);
404 hdr->driver_status = driver_byte(rq->errors);
405 hdr->info = 0;
406 if (hdr->device_status || hdr->transport_status || hdr->driver_status)
407 hdr->info |= SG_INFO_CHECK;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100408 hdr->response_len = 0;
409
410 if (rq->sense_len && hdr->response) {
Jens Axboe25fd1642007-07-17 08:52:29 +0200411 int len = min_t(unsigned int, hdr->max_response_len,
412 rq->sense_len);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100413
Namhyung Kim2b727c62011-06-20 13:27:45 +0200414 ret = copy_to_user((void __user *)(unsigned long)hdr->response,
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100415 rq->sense, len);
416 if (!ret)
417 hdr->response_len = len;
418 else
419 ret = -EFAULT;
420 }
421
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200422 if (rq->next_rq) {
Tejun Heoc3a4d782009-05-07 22:24:37 +0900423 hdr->dout_resid = rq->resid_len;
424 hdr->din_resid = rq->next_rq->resid_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200425 blk_rq_unmap_user(bidi_bio);
426 blk_put_request(rq->next_rq);
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900427 } else if (rq_data_dir(rq) == READ)
Tejun Heoc3a4d782009-05-07 22:24:37 +0900428 hdr->din_resid = rq->resid_len;
FUJITA Tomonori0c6a89b2007-07-29 23:00:46 +0900429 else
Tejun Heoc3a4d782009-05-07 22:24:37 +0900430 hdr->dout_resid = rq->resid_len;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200431
James Bottomley2d507a02007-12-29 10:59:53 -0600432 /*
433 * If the request generated a negative error number, return it
434 * (providing we aren't already returning an error); if it's
435 * just a protocol response (i.e. non negative), that gets
436 * processed above.
437 */
438 if (!ret && rq->errors < 0)
439 ret = rq->errors;
440
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100441 blk_rq_unmap_user(bio);
FUJITA Tomonori9f5de6b2008-04-30 13:16:21 +0900442 if (rq->cmd != rq->__cmd)
443 kfree(rq->cmd);
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100444 blk_put_request(rq);
445
446 return ret;
447}
448
Peter Zijlstra2c561242015-02-03 12:55:31 +0100449static bool bsg_complete(struct bsg_device *bd)
450{
451 bool ret = false;
452 bool spin;
453
454 do {
455 spin_lock_irq(&bd->lock);
456
457 BUG_ON(bd->done_cmds > bd->queued_cmds);
458
459 /*
460 * All commands consumed.
461 */
462 if (bd->done_cmds == bd->queued_cmds)
463 ret = true;
464
465 spin = !test_bit(BSG_F_BLOCK, &bd->flags);
466
467 spin_unlock_irq(&bd->lock);
468 } while (!ret && spin);
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 */
Peter Zijlstra2c561242015-02-03 12:55:31 +0100483 io_wait_event(bd->wq_done, bsg_complete(bd));
Jens Axboe3d6392c2007-07-09 12:38:05 +0200484
485 /*
486 * discard done commands
487 */
488 ret = 0;
489 do {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200490 spin_lock_irq(&bd->lock);
491 if (!bd->queued_cmds) {
492 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200493 break;
494 }
FUJITA Tomonoriefba1a32007-06-07 13:24:06 +0200495 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200496
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200497 bc = bsg_get_done_cmd(bd);
498 if (IS_ERR(bc))
499 break;
500
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200501 tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
502 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200503 if (!ret)
504 ret = tret;
505
506 bsg_free_command(bc);
507 } while (1);
508
509 return ret;
510}
511
Jens Axboe25fd1642007-07-17 08:52:29 +0200512static int
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200513__bsg_read(char __user *buf, size_t count, struct bsg_device *bd,
514 const struct iovec *iov, ssize_t *bytes_read)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200515{
516 struct bsg_command *bc;
517 int nr_commands, ret;
518
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100519 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200520 return -EINVAL;
521
522 ret = 0;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100523 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200524 while (nr_commands) {
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200525 bc = bsg_get_done_cmd(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200526 if (IS_ERR(bc)) {
527 ret = PTR_ERR(bc);
528 break;
529 }
530
531 /*
532 * this is the only case where we need to copy data back
533 * after completing the request. so do that here,
534 * bsg_complete_work() cannot do that for us
535 */
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200536 ret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio,
537 bc->bidi_bio);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200538
Jens Axboe25fd1642007-07-17 08:52:29 +0200539 if (copy_to_user(buf, &bc->hdr, sizeof(bc->hdr)))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200540 ret = -EFAULT;
541
542 bsg_free_command(bc);
543
544 if (ret)
545 break;
546
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100547 buf += sizeof(struct sg_io_v4);
548 *bytes_read += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200549 nr_commands--;
550 }
551
552 return ret;
553}
554
555static inline void bsg_set_block(struct bsg_device *bd, struct file *file)
556{
557 if (file->f_flags & O_NONBLOCK)
558 clear_bit(BSG_F_BLOCK, &bd->flags);
559 else
560 set_bit(BSG_F_BLOCK, &bd->flags);
561}
562
Jens Axboe25fd1642007-07-17 08:52:29 +0200563/*
564 * Check if the error is a "real" error that we should return.
565 */
Jens Axboe3d6392c2007-07-09 12:38:05 +0200566static inline int err_block_err(int ret)
567{
568 if (ret && ret != -ENOSPC && ret != -ENODATA && ret != -EAGAIN)
569 return 1;
570
571 return 0;
572}
573
574static ssize_t
575bsg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
576{
577 struct bsg_device *bd = file->private_data;
578 int ret;
579 ssize_t bytes_read;
580
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100581 dprintk("%s: read %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200582
583 bsg_set_block(bd, file);
Adel Gadllah0b07de82008-06-26 13:48:27 +0200584
Jens Axboe3d6392c2007-07-09 12:38:05 +0200585 bytes_read = 0;
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200586 ret = __bsg_read(buf, count, bd, NULL, &bytes_read);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200587 *ppos = bytes_read;
588
Namhyung Kim44194e32011-06-20 13:27:44 +0200589 if (!bytes_read || err_block_err(ret))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200590 bytes_read = ret;
591
592 return bytes_read;
593}
594
Jens Axboe25fd1642007-07-17 08:52:29 +0200595static int __bsg_write(struct bsg_device *bd, const char __user *buf,
Al Viroaeb5d722008-09-02 15:28:45 -0400596 size_t count, ssize_t *bytes_written,
597 fmode_t has_write_perm)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200598{
599 struct bsg_command *bc;
600 struct request *rq;
601 int ret, nr_commands;
602
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100603 if (count % sizeof(struct sg_io_v4))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200604 return -EINVAL;
605
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100606 nr_commands = count / sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200607 rq = NULL;
608 bc = NULL;
609 ret = 0;
610 while (nr_commands) {
Jens Axboe165125e2007-07-24 09:28:11 +0200611 struct request_queue *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200612
FUJITA Tomonorie7d72172007-05-08 15:32:03 +0200613 bc = bsg_alloc_command(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200614 if (IS_ERR(bc)) {
615 ret = PTR_ERR(bc);
616 bc = NULL;
617 break;
618 }
619
Jens Axboe3d6392c2007-07-09 12:38:05 +0200620 if (copy_from_user(&bc->hdr, buf, sizeof(bc->hdr))) {
621 ret = -EFAULT;
622 break;
623 }
624
625 /*
626 * get a request, fill in the blanks, and add to request queue
627 */
Boaz Harroshc1c201202009-02-03 07:47:29 +0100628 rq = bsg_map_hdr(bd, &bc->hdr, has_write_perm, bc->sense);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200629 if (IS_ERR(rq)) {
630 ret = PTR_ERR(rq);
631 rq = NULL;
632 break;
633 }
634
635 bsg_add_command(bd, q, bc, rq);
636 bc = NULL;
637 rq = NULL;
638 nr_commands--;
FUJITA Tomonori70e36ec2006-12-20 11:20:15 +0100639 buf += sizeof(struct sg_io_v4);
Jens Axboe25fd1642007-07-17 08:52:29 +0200640 *bytes_written += sizeof(struct sg_io_v4);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200641 }
642
Jens Axboe3d6392c2007-07-09 12:38:05 +0200643 if (bc)
644 bsg_free_command(bc);
645
646 return ret;
647}
648
649static ssize_t
650bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
651{
652 struct bsg_device *bd = file->private_data;
Jens Axboe25fd1642007-07-17 08:52:29 +0200653 ssize_t bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200654 int ret;
655
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100656 dprintk("%s: write %Zd bytes\n", bd->name, count);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200657
Al Viro3f3a6bb2016-12-16 13:42:06 -0500658 if (unlikely(segment_eq(get_fs(), KERNEL_DS)))
659 return -EINVAL;
660
Jens Axboe3d6392c2007-07-09 12:38:05 +0200661 bsg_set_block(bd, file);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200662
Jens Axboe25fd1642007-07-17 08:52:29 +0200663 bytes_written = 0;
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900664 ret = __bsg_write(bd, buf, count, &bytes_written,
665 file->f_mode & FMODE_WRITE);
666
Jens Axboe25fd1642007-07-17 08:52:29 +0200667 *ppos = bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200668
669 /*
670 * return bytes written on non-fatal errors
671 */
Namhyung Kim44194e32011-06-20 13:27:44 +0200672 if (!bytes_written || err_block_err(ret))
Jens Axboe25fd1642007-07-17 08:52:29 +0200673 bytes_written = ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200674
Jens Axboe25fd1642007-07-17 08:52:29 +0200675 dprintk("%s: returning %Zd\n", bd->name, bytes_written);
676 return bytes_written;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200677}
678
Jens Axboe3d6392c2007-07-09 12:38:05 +0200679static struct bsg_device *bsg_alloc_device(void)
680{
Jens Axboe3d6392c2007-07-09 12:38:05 +0200681 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200682
683 bd = kzalloc(sizeof(struct bsg_device), GFP_KERNEL);
684 if (unlikely(!bd))
685 return NULL;
686
687 spin_lock_init(&bd->lock);
688
Jens Axboe5309cb32007-01-23 16:24:41 +0100689 bd->max_queue = BSG_DEFAULT_CMDS;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200690
691 INIT_LIST_HEAD(&bd->busy_list);
692 INIT_LIST_HEAD(&bd->done_list);
693 INIT_HLIST_NODE(&bd->dev_list);
694
695 init_waitqueue_head(&bd->wq_free);
696 init_waitqueue_head(&bd->wq_done);
697 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200698}
699
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900700static void bsg_kref_release_function(struct kref *kref)
701{
702 struct bsg_class_device *bcd =
703 container_of(kref, struct bsg_class_device, ref);
James Bottomley8df5fc02008-07-07 15:50:01 -0500704 struct device *parent = bcd->parent;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900705
706 if (bcd->release)
707 bcd->release(bcd->parent);
708
James Bottomley8df5fc02008-07-07 15:50:01 -0500709 put_device(parent);
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900710}
711
Jens Axboe3d6392c2007-07-09 12:38:05 +0200712static int bsg_put_device(struct bsg_device *bd)
713{
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900714 int ret = 0, do_free;
715 struct request_queue *q = bd->queue;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200716
717 mutex_lock(&bsg_mutex);
718
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900719 do_free = atomic_dec_and_test(&bd->ref_count);
FUJITA Tomonori3f27e3e2008-05-29 07:56:55 +0900720 if (!do_free) {
721 mutex_unlock(&bsg_mutex);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200722 goto out;
FUJITA Tomonori3f27e3e2008-05-29 07:56:55 +0900723 }
724
725 hlist_del(&bd->dev_list);
726 mutex_unlock(&bsg_mutex);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200727
728 dprintk("%s: tearing down\n", bd->name);
729
730 /*
731 * close can always block
732 */
733 set_bit(BSG_F_BLOCK, &bd->flags);
734
735 /*
736 * correct error detection baddies here again. it's the responsibility
737 * of the app to properly reap commands before close() if it wants
738 * fool-proof error detection
739 */
740 ret = bsg_complete_all_commands(bd);
741
Jens Axboe5309cb32007-01-23 16:24:41 +0100742 kfree(bd);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200743out:
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900744 kref_put(&q->bsg_dev.ref, bsg_kref_release_function);
745 if (do_free)
746 blk_put_queue(q);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200747 return ret;
748}
749
750static struct bsg_device *bsg_add_device(struct inode *inode,
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200751 struct request_queue *rq,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200752 struct file *file)
753{
Jens Axboe25fd1642007-07-17 08:52:29 +0200754 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200755#ifdef BSG_DEBUG
756 unsigned char buf[32];
757#endif
Tejun Heo09ac46c2011-12-14 00:33:38 +0100758 if (!blk_get_queue(rq))
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900759 return ERR_PTR(-ENXIO);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200760
761 bd = bsg_alloc_device();
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900762 if (!bd) {
763 blk_put_queue(rq);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200764 return ERR_PTR(-ENOMEM);
FUJITA Tomonoric3ff1b92008-03-31 10:03:39 +0900765 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200766
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200767 bd->queue = rq;
Adel Gadllah0b07de82008-06-26 13:48:27 +0200768
Jens Axboe3d6392c2007-07-09 12:38:05 +0200769 bsg_set_block(bd, file);
770
771 atomic_set(&bd->ref_count, 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200772 mutex_lock(&bsg_mutex);
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900773 hlist_add_head(&bd->dev_list, bsg_dev_idx_hash(iminor(inode)));
Jens Axboe3d6392c2007-07-09 12:38:05 +0200774
Kay Sievers3ada8b72009-01-06 10:44:43 -0800775 strncpy(bd->name, dev_name(rq->bsg_dev.class_dev), sizeof(bd->name) - 1);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200776 dprintk("bound to <%s>, max queue %d\n",
FUJITA Tomonori9e69fbb2006-12-20 11:18:22 +0100777 format_dev_t(buf, inode->i_rdev), bd->max_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200778
779 mutex_unlock(&bsg_mutex);
780 return bd;
781}
782
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900783static struct bsg_device *__bsg_get_device(int minor, struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200784{
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900785 struct bsg_device *bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200786
787 mutex_lock(&bsg_mutex);
788
Sasha Levinb67bfe02013-02-27 17:06:00 -0800789 hlist_for_each_entry(bd, bsg_dev_idx_hash(minor), dev_list) {
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900790 if (bd->queue == q) {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200791 atomic_inc(&bd->ref_count);
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900792 goto found;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200793 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200794 }
FUJITA Tomonori43ac9e62008-03-31 10:03:40 +0900795 bd = NULL;
796found:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200797 mutex_unlock(&bsg_mutex);
798 return bd;
799}
800
801static struct bsg_device *bsg_get_device(struct inode *inode, struct file *file)
802{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900803 struct bsg_device *bd;
804 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200805
Jens Axboe3d6392c2007-07-09 12:38:05 +0200806 /*
807 * find the class device
808 */
Jens Axboe3d6392c2007-07-09 12:38:05 +0200809 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900810 bcd = idr_find(&bsg_minor_idr, iminor(inode));
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900811 if (bcd)
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900812 kref_get(&bcd->ref);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200813 mutex_unlock(&bsg_mutex);
814
815 if (!bcd)
816 return ERR_PTR(-ENODEV);
817
FUJITA Tomonori842ea772008-03-31 10:03:41 +0900818 bd = __bsg_get_device(iminor(inode), bcd->queue);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900819 if (bd)
820 return bd;
821
822 bd = bsg_add_device(inode, bcd->queue, file);
823 if (IS_ERR(bd))
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900824 kref_put(&bcd->ref, bsg_kref_release_function);
FUJITA Tomonorid45ac4f2008-03-31 10:03:38 +0900825
826 return bd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200827}
828
829static int bsg_open(struct inode *inode, struct file *file)
830{
Jonathan Corbet75bd2ef2008-05-15 09:09:23 -0600831 struct bsg_device *bd;
832
Jonathan Corbet75bd2ef2008-05-15 09:09:23 -0600833 bd = bsg_get_device(inode, file);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200834
835 if (IS_ERR(bd))
836 return PTR_ERR(bd);
837
838 file->private_data = bd;
839 return 0;
840}
841
842static int bsg_release(struct inode *inode, struct file *file)
843{
844 struct bsg_device *bd = file->private_data;
845
846 file->private_data = NULL;
847 return bsg_put_device(bd);
848}
849
850static unsigned int bsg_poll(struct file *file, poll_table *wait)
851{
852 struct bsg_device *bd = file->private_data;
853 unsigned int mask = 0;
854
855 poll_wait(file, &bd->wq_done, wait);
856 poll_wait(file, &bd->wq_free, wait);
857
858 spin_lock_irq(&bd->lock);
859 if (!list_empty(&bd->done_list))
860 mask |= POLLIN | POLLRDNORM;
Namhyung Kim80ceb052011-06-20 13:27:44 +0200861 if (bd->queued_cmds < bd->max_queue)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200862 mask |= POLLOUT;
863 spin_unlock_irq(&bd->lock);
864
865 return mask;
866}
867
Jens Axboe25fd1642007-07-17 08:52:29 +0200868static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200869{
870 struct bsg_device *bd = file->private_data;
871 int __user *uarg = (int __user *) arg;
James Bottomley2d507a02007-12-29 10:59:53 -0600872 int ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200873
Jens Axboe3d6392c2007-07-09 12:38:05 +0200874 switch (cmd) {
875 /*
876 * our own ioctls
877 */
878 case SG_GET_COMMAND_Q:
879 return put_user(bd->max_queue, uarg);
Jens Axboe5309cb32007-01-23 16:24:41 +0100880 case SG_SET_COMMAND_Q: {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200881 int queue;
882
883 if (get_user(queue, uarg))
884 return -EFAULT;
Jens Axboe5309cb32007-01-23 16:24:41 +0100885 if (queue < 1)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200886 return -EINVAL;
887
Jens Axboe5309cb32007-01-23 16:24:41 +0100888 spin_lock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200889 bd->max_queue = queue;
Jens Axboe5309cb32007-01-23 16:24:41 +0100890 spin_unlock_irq(&bd->lock);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200891 return 0;
892 }
893
894 /*
895 * SCSI/sg ioctls
896 */
897 case SG_GET_VERSION_NUM:
898 case SCSI_IOCTL_GET_IDLUN:
899 case SCSI_IOCTL_GET_BUS_NUMBER:
900 case SG_SET_TIMEOUT:
901 case SG_GET_TIMEOUT:
902 case SG_GET_RESERVED_SIZE:
903 case SG_SET_RESERVED_SIZE:
904 case SG_EMULATED_HOST:
Jens Axboe3d6392c2007-07-09 12:38:05 +0200905 case SCSI_IOCTL_SEND_COMMAND: {
906 void __user *uarg = (void __user *) arg;
Al Viro74f3c8a2007-08-27 15:38:10 -0400907 return scsi_cmd_ioctl(bd->queue, NULL, file->f_mode, cmd, uarg);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200908 }
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100909 case SG_IO: {
910 struct request *rq;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200911 struct bio *bio, *bidi_bio = NULL;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100912 struct sg_io_v4 hdr;
Boaz Harrosh05378942009-03-24 12:23:40 +0100913 int at_head;
Boaz Harroshc1c201202009-02-03 07:47:29 +0100914 u8 sense[SCSI_SENSE_BUFFERSIZE];
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100915
916 if (copy_from_user(&hdr, uarg, sizeof(hdr)))
917 return -EFAULT;
918
Boaz Harroshc1c201202009-02-03 07:47:29 +0100919 rq = bsg_map_hdr(bd, &hdr, file->f_mode & FMODE_WRITE, sense);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100920 if (IS_ERR(rq))
921 return PTR_ERR(rq);
922
923 bio = rq->bio;
FUJITA Tomonori2c9ecdf2007-07-16 08:52:15 +0200924 if (rq->next_rq)
925 bidi_bio = rq->next_rq->bio;
Boaz Harrosh05378942009-03-24 12:23:40 +0100926
927 at_head = (0 == (hdr.flags & BSG_FLAG_Q_AT_TAIL));
928 blk_execute_rq(bd->queue, NULL, rq, at_head);
James Bottomley2d507a02007-12-29 10:59:53 -0600929 ret = blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio);
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100930
931 if (copy_to_user(uarg, &hdr, sizeof(hdr)))
932 return -EFAULT;
Jens Axboeb711afa2006-12-20 11:25:23 +0100933
James Bottomley2d507a02007-12-29 10:59:53 -0600934 return ret;
FUJITA Tomonori10e88552006-12-20 11:20:57 +0100935 }
Jens Axboe3d6392c2007-07-09 12:38:05 +0200936 /*
937 * block device ioctls
938 */
939 default:
940#if 0
941 return ioctl_by_bdev(bd->bdev, cmd, arg);
942#else
943 return -ENOTTY;
944#endif
945 }
946}
947
Arjan van de Ven7344be02007-10-15 11:01:53 +0200948static const struct file_operations bsg_fops = {
Jens Axboe3d6392c2007-07-09 12:38:05 +0200949 .read = bsg_read,
950 .write = bsg_write,
951 .poll = bsg_poll,
952 .open = bsg_open,
953 .release = bsg_release,
Jens Axboe25fd1642007-07-17 08:52:29 +0200954 .unlocked_ioctl = bsg_ioctl,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200955 .owner = THIS_MODULE,
Arnd Bergmann6038f372010-08-15 18:52:59 +0200956 .llseek = default_llseek,
Jens Axboe3d6392c2007-07-09 12:38:05 +0200957};
958
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200959void bsg_unregister_queue(struct request_queue *q)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200960{
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200961 struct bsg_class_device *bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200962
FUJITA Tomonoridf468822007-07-21 13:23:25 +0900963 if (!bcd->class_dev)
964 return;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200965
966 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900967 idr_remove(&bsg_minor_idr, bcd->minor);
Stanislaw Gruszka37b40ad2012-02-08 20:02:03 +0100968 if (q->kobj.sd)
969 sysfs_remove_link(&q->kobj, "bsg");
Tony Jonesee959b02008-02-22 00:13:36 +0100970 device_unregister(bcd->class_dev);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200971 bcd->class_dev = NULL;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900972 kref_put(&bcd->ref, bsg_kref_release_function);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200973 mutex_unlock(&bsg_mutex);
974}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +0200975EXPORT_SYMBOL_GPL(bsg_unregister_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200976
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +0900977int bsg_register_queue(struct request_queue *q, struct device *parent,
978 const char *name, void (*release)(struct device *))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200979{
FUJITA Tomonori598443a2007-07-23 09:33:26 +0900980 struct bsg_class_device *bcd;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200981 dev_t dev;
Tejun Heobab998d2013-02-27 17:03:57 -0800982 int ret;
Tony Jonesee959b02008-02-22 00:13:36 +0100983 struct device *class_dev = NULL;
James Bottomley39dca552007-07-20 18:22:17 -0500984 const char *devname;
985
986 if (name)
987 devname = name;
988 else
Kay Sievers3ada8b72009-01-06 10:44:43 -0800989 devname = dev_name(parent);
Jens Axboe3d6392c2007-07-09 12:38:05 +0200990
991 /*
992 * we need a proper transport to send commands, not a stacked device
993 */
Jens Axboe49fd5242014-04-16 10:57:18 -0600994 if (!queue_is_rq_based(q))
Jens Axboe3d6392c2007-07-09 12:38:05 +0200995 return 0;
996
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200997 bcd = &q->bsg_dev;
Jens Axboe3d6392c2007-07-09 12:38:05 +0200998 memset(bcd, 0, sizeof(*bcd));
Jens Axboe3d6392c2007-07-09 12:38:05 +0200999
1000 mutex_lock(&bsg_mutex);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001001
Tejun Heobab998d2013-02-27 17:03:57 -08001002 ret = idr_alloc(&bsg_minor_idr, bcd, 0, BSG_MAX_DEVS, GFP_KERNEL);
1003 if (ret < 0) {
1004 if (ret == -ENOSPC) {
1005 printk(KERN_ERR "bsg: too many bsg devices\n");
1006 ret = -EINVAL;
1007 }
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001008 goto unlock;
1009 }
1010
Tejun Heobab998d2013-02-27 17:03:57 -08001011 bcd->minor = ret;
FUJITA Tomonorid351af02007-07-09 12:40:35 +02001012 bcd->queue = q;
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001013 bcd->parent = get_device(parent);
1014 bcd->release = release;
1015 kref_init(&bcd->ref);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001016 dev = MKDEV(bsg_major, bcd->minor);
Greg Kroah-Hartman1ff9f542008-07-21 20:03:34 -07001017 class_dev = device_create(bsg_class, parent, dev, NULL, "%s", devname);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001018 if (IS_ERR(class_dev)) {
1019 ret = PTR_ERR(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001020 goto put_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001021 }
1022 bcd->class_dev = class_dev;
1023
Linus Torvaldsabce8912007-07-16 11:18:23 -07001024 if (q->kobj.sd) {
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001025 ret = sysfs_create_link(&q->kobj, &bcd->class_dev->kobj, "bsg");
1026 if (ret)
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001027 goto unregister_class_dev;
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001028 }
1029
Jens Axboe3d6392c2007-07-09 12:38:05 +02001030 mutex_unlock(&bsg_mutex);
1031 return 0;
James Bottomley6826ee42007-07-20 16:50:10 -05001032
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001033unregister_class_dev:
Tony Jonesee959b02008-02-22 00:13:36 +01001034 device_unregister(class_dev);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001035put_dev:
FUJITA Tomonori97f46ae2008-04-19 00:43:14 +09001036 put_device(parent);
Tejun Heobab998d2013-02-27 17:03:57 -08001037 idr_remove(&bsg_minor_idr, bcd->minor);
FUJITA Tomonori598443a2007-07-23 09:33:26 +09001038unlock:
Jens Axboe264a0472007-01-23 16:30:17 +01001039 mutex_unlock(&bsg_mutex);
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001040 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001041}
FUJITA Tomonori4cf07232007-03-30 11:19:39 +02001042EXPORT_SYMBOL_GPL(bsg_register_queue);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001043
Greg Kroah-Hartman7e7654a2007-09-12 15:06:57 -07001044static struct cdev bsg_cdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001045
Al Viro2c9ede52011-07-23 20:24:48 -04001046static char *bsg_devnode(struct device *dev, umode_t *mode)
Kay Sievers2bdf9142009-04-30 15:23:42 +02001047{
1048 return kasprintf(GFP_KERNEL, "bsg/%s", dev_name(dev));
1049}
1050
Jens Axboe3d6392c2007-07-09 12:38:05 +02001051static int __init bsg_init(void)
1052{
1053 int ret, i;
Jens Axboe46f6ef42007-07-17 08:56:10 +02001054 dev_t devid;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001055
Jens Axboe5309cb32007-01-23 16:24:41 +01001056 bsg_cmd_cachep = kmem_cache_create("bsg_cmd",
Paul Mundt20c2df82007-07-20 10:11:58 +09001057 sizeof(struct bsg_command), 0, 0, NULL);
Jens Axboe5309cb32007-01-23 16:24:41 +01001058 if (!bsg_cmd_cachep) {
1059 printk(KERN_ERR "bsg: failed creating slab cache\n");
1060 return -ENOMEM;
1061 }
1062
Jens Axboe25fd1642007-07-17 08:52:29 +02001063 for (i = 0; i < BSG_LIST_ARRAY_SIZE; i++)
Jens Axboe3d6392c2007-07-09 12:38:05 +02001064 INIT_HLIST_HEAD(&bsg_device_list[i]);
1065
1066 bsg_class = class_create(THIS_MODULE, "bsg");
Jens Axboe5309cb32007-01-23 16:24:41 +01001067 if (IS_ERR(bsg_class)) {
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001068 ret = PTR_ERR(bsg_class);
1069 goto destroy_kmemcache;
Jens Axboe5309cb32007-01-23 16:24:41 +01001070 }
Kay Sieverse454cea2009-09-18 23:01:12 +02001071 bsg_class->devnode = bsg_devnode;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001072
Jens Axboe46f6ef42007-07-17 08:56:10 +02001073 ret = alloc_chrdev_region(&devid, 0, BSG_MAX_DEVS, "bsg");
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001074 if (ret)
1075 goto destroy_bsg_class;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001076
Jens Axboe46f6ef42007-07-17 08:56:10 +02001077 bsg_major = MAJOR(devid);
1078
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001079 cdev_init(&bsg_cdev, &bsg_fops);
Jens Axboe46f6ef42007-07-17 08:56:10 +02001080 ret = cdev_add(&bsg_cdev, MKDEV(bsg_major, 0), BSG_MAX_DEVS);
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001081 if (ret)
1082 goto unregister_chrdev;
FUJITA Tomonori292b7f22007-03-28 13:29:58 +02001083
Jens Axboe5d3a8cd2007-07-17 15:10:09 +02001084 printk(KERN_INFO BSG_DESCRIPTION " version " BSG_VERSION
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001085 " loaded (major %d)\n", bsg_major);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001086 return 0;
FUJITA Tomonori9b9f7702007-07-17 12:20:46 +02001087unregister_chrdev:
1088 unregister_chrdev_region(MKDEV(bsg_major, 0), BSG_MAX_DEVS);
1089destroy_bsg_class:
1090 class_destroy(bsg_class);
1091destroy_kmemcache:
1092 kmem_cache_destroy(bsg_cmd_cachep);
1093 return ret;
Jens Axboe3d6392c2007-07-09 12:38:05 +02001094}
1095
1096MODULE_AUTHOR("Jens Axboe");
FUJITA Tomonori0ed081c2007-07-17 12:21:35 +02001097MODULE_DESCRIPTION(BSG_DESCRIPTION);
Jens Axboe3d6392c2007-07-09 12:38:05 +02001098MODULE_LICENSE("GPL");
1099
FUJITA Tomonori4e2872d2007-03-28 13:29:24 +02001100device_initcall(bsg_init);