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v4.17
 
  1/*
  2 *  BSG helper library
  3 *
  4 *  Copyright (C) 2008   James Smart, Emulex Corporation
  5 *  Copyright (C) 2011   Red Hat, Inc.  All rights reserved.
  6 *  Copyright (C) 2011   Mike Christie
  7 *
  8 *  This program is free software; you can redistribute it and/or modify
  9 *  it under the terms of the GNU General Public License as published by
 10 *  the Free Software Foundation; either version 2 of the License, or
 11 *  (at your option) any later version.
 12 *
 13 *  This program is distributed in the hope that it will be useful,
 14 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 15 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 16 *  GNU General Public License for more details.
 17 *
 18 *  You should have received a copy of the GNU General Public License
 19 *  along with this program; if not, write to the Free Software
 20 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 21 *
 22 */
 
 23#include <linux/slab.h>
 24#include <linux/blkdev.h>
 25#include <linux/delay.h>
 26#include <linux/scatterlist.h>
 27#include <linux/bsg-lib.h>
 28#include <linux/export.h>
 29#include <scsi/scsi_cmnd.h>
 30#include <scsi/sg.h>
 31
 32#define uptr64(val) ((void __user *)(uintptr_t)(val))
 33
 34static int bsg_transport_check_proto(struct sg_io_v4 *hdr)
 
 
 
 
 
 
 
 
 35{
 
 
 
 
 
 
 36	if (hdr->protocol != BSG_PROTOCOL_SCSI  ||
 37	    hdr->subprotocol != BSG_SUB_PROTOCOL_SCSI_TRANSPORT)
 38		return -EINVAL;
 39	if (!capable(CAP_SYS_RAWIO))
 40		return -EPERM;
 41	return 0;
 42}
 43
 44static int bsg_transport_fill_hdr(struct request *rq, struct sg_io_v4 *hdr,
 45		fmode_t mode)
 46{
 47	struct bsg_job *job = blk_mq_rq_to_pdu(rq);
 
 
 
 
 
 
 
 
 48
 49	job->request_len = hdr->request_len;
 50	job->request = memdup_user(uptr64(hdr->request), hdr->request_len);
 51	if (IS_ERR(job->request))
 52		return PTR_ERR(job->request);
 53	return 0;
 54}
 55
 56static int bsg_transport_complete_rq(struct request *rq, struct sg_io_v4 *hdr)
 57{
 58	struct bsg_job *job = blk_mq_rq_to_pdu(rq);
 59	int ret = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 60
 61	/*
 62	 * The assignments below don't make much sense, but are kept for
 63	 * bug by bug backwards compatibility:
 64	 */
 65	hdr->device_status = job->result & 0xff;
 66	hdr->transport_status = host_byte(job->result);
 67	hdr->driver_status = driver_byte(job->result);
 68	hdr->info = 0;
 69	if (hdr->device_status || hdr->transport_status || hdr->driver_status)
 70		hdr->info |= SG_INFO_CHECK;
 71	hdr->response_len = 0;
 72
 73	if (job->result < 0) {
 74		/* we're only returning the result field in the reply */
 75		job->reply_len = sizeof(u32);
 76		ret = job->result;
 77	}
 78
 79	if (job->reply_len && hdr->response) {
 80		int len = min(hdr->max_response_len, job->reply_len);
 81
 82		if (copy_to_user(uptr64(hdr->response), job->reply, len))
 83			ret = -EFAULT;
 84		else
 85			hdr->response_len = len;
 86	}
 87
 88	/* we assume all request payload was transferred, residual == 0 */
 89	hdr->dout_resid = 0;
 90
 91	if (rq->next_rq) {
 92		unsigned int rsp_len = job->reply_payload.payload_len;
 93
 94		if (WARN_ON(job->reply_payload_rcv_len > rsp_len))
 95			hdr->din_resid = 0;
 96		else
 97			hdr->din_resid = rsp_len - job->reply_payload_rcv_len;
 98	} else {
 99		hdr->din_resid = 0;
100	}
101
102	return ret;
103}
104
105static void bsg_transport_free_rq(struct request *rq)
106{
107	struct bsg_job *job = blk_mq_rq_to_pdu(rq);
108
 
109	kfree(job->request);
 
 
 
110}
111
112static const struct bsg_ops bsg_transport_ops = {
113	.check_proto		= bsg_transport_check_proto,
114	.fill_hdr		= bsg_transport_fill_hdr,
115	.complete_rq		= bsg_transport_complete_rq,
116	.free_rq		= bsg_transport_free_rq,
117};
118
119/**
120 * bsg_teardown_job - routine to teardown a bsg job
121 * @kref: kref inside bsg_job that is to be torn down
122 */
123static void bsg_teardown_job(struct kref *kref)
124{
125	struct bsg_job *job = container_of(kref, struct bsg_job, kref);
126	struct request *rq = blk_mq_rq_from_pdu(job);
127
128	put_device(job->dev);	/* release reference for the request */
129
130	kfree(job->request_payload.sg_list);
131	kfree(job->reply_payload.sg_list);
132
133	blk_end_request_all(rq, BLK_STS_OK);
134}
135
136void bsg_job_put(struct bsg_job *job)
137{
138	kref_put(&job->kref, bsg_teardown_job);
139}
140EXPORT_SYMBOL_GPL(bsg_job_put);
141
142int bsg_job_get(struct bsg_job *job)
143{
144	return kref_get_unless_zero(&job->kref);
145}
146EXPORT_SYMBOL_GPL(bsg_job_get);
147
148/**
149 * bsg_job_done - completion routine for bsg requests
150 * @job: bsg_job that is complete
151 * @result: job reply result
152 * @reply_payload_rcv_len: length of payload recvd
153 *
154 * The LLD should call this when the bsg job has completed.
155 */
156void bsg_job_done(struct bsg_job *job, int result,
157		  unsigned int reply_payload_rcv_len)
158{
 
 
159	job->result = result;
160	job->reply_payload_rcv_len = reply_payload_rcv_len;
161	blk_complete_request(blk_mq_rq_from_pdu(job));
 
162}
163EXPORT_SYMBOL_GPL(bsg_job_done);
164
165/**
166 * bsg_softirq_done - softirq done routine for destroying the bsg requests
167 * @rq: BSG request that holds the job to be destroyed
168 */
169static void bsg_softirq_done(struct request *rq)
170{
171	struct bsg_job *job = blk_mq_rq_to_pdu(rq);
172
173	bsg_job_put(job);
174}
175
176static int bsg_map_buffer(struct bsg_buffer *buf, struct request *req)
177{
178	size_t sz = (sizeof(struct scatterlist) * req->nr_phys_segments);
179
180	BUG_ON(!req->nr_phys_segments);
181
182	buf->sg_list = kzalloc(sz, GFP_KERNEL);
183	if (!buf->sg_list)
184		return -ENOMEM;
185	sg_init_table(buf->sg_list, req->nr_phys_segments);
186	buf->sg_cnt = blk_rq_map_sg(req->q, req, buf->sg_list);
187	buf->payload_len = blk_rq_bytes(req);
188	return 0;
189}
190
191/**
192 * bsg_prepare_job - create the bsg_job structure for the bsg request
193 * @dev: device that is being sent the bsg request
194 * @req: BSG request that needs a job structure
195 */
196static bool bsg_prepare_job(struct device *dev, struct request *req)
197{
198	struct request *rsp = req->next_rq;
199	struct bsg_job *job = blk_mq_rq_to_pdu(req);
200	int ret;
201
202	job->timeout = req->timeout;
203
204	if (req->bio) {
205		ret = bsg_map_buffer(&job->request_payload, req);
206		if (ret)
207			goto failjob_rls_job;
208	}
209	if (rsp && rsp->bio) {
210		ret = bsg_map_buffer(&job->reply_payload, rsp);
211		if (ret)
212			goto failjob_rls_rqst_payload;
213	}
214	job->dev = dev;
215	/* take a reference for the request */
216	get_device(job->dev);
217	kref_init(&job->kref);
218	return true;
219
220failjob_rls_rqst_payload:
221	kfree(job->request_payload.sg_list);
222failjob_rls_job:
223	job->result = -ENOMEM;
224	return false;
225}
226
227/**
228 * bsg_request_fn - generic handler for bsg requests
229 * @q: request queue to manage
 
230 *
231 * On error the create_bsg_job function should return a -Exyz error value
232 * that will be set to ->result.
233 *
234 * Drivers/subsys should pass this to the queue init function.
235 */
236static void bsg_request_fn(struct request_queue *q)
237	__releases(q->queue_lock)
238	__acquires(q->queue_lock)
239{
 
240	struct device *dev = q->queuedata;
241	struct request *req;
 
 
 
242	int ret;
243
 
 
244	if (!get_device(dev))
245		return;
246
247	while (1) {
248		req = blk_fetch_request(q);
249		if (!req)
250			break;
251		spin_unlock_irq(q->queue_lock);
252
253		if (!bsg_prepare_job(dev, req)) {
254			blk_end_request_all(req, BLK_STS_OK);
255			spin_lock_irq(q->queue_lock);
256			continue;
257		}
258
259		ret = q->bsg_job_fn(blk_mq_rq_to_pdu(req));
260		spin_lock_irq(q->queue_lock);
261		if (ret)
262			break;
263	}
264
265	spin_unlock_irq(q->queue_lock);
266	put_device(dev);
267	spin_lock_irq(q->queue_lock);
268}
269
270/* called right after the request is allocated for the request_queue */
271static int bsg_init_rq(struct request_queue *q, struct request *req, gfp_t gfp)
 
272{
273	struct bsg_job *job = blk_mq_rq_to_pdu(req);
274
275	job->reply = kzalloc(SCSI_SENSE_BUFFERSIZE, gfp);
276	if (!job->reply)
277		return -ENOMEM;
278	return 0;
279}
280
281/* called right before the request is given to the request_queue user */
282static void bsg_initialize_rq(struct request *req)
283{
284	struct bsg_job *job = blk_mq_rq_to_pdu(req);
285	void *reply = job->reply;
286
287	memset(job, 0, sizeof(*job));
288	job->reply = reply;
289	job->reply_len = SCSI_SENSE_BUFFERSIZE;
290	job->dd_data = job + 1;
291}
292
293static void bsg_exit_rq(struct request_queue *q, struct request *req)
294{
295	struct bsg_job *job = blk_mq_rq_to_pdu(req);
 
 
 
 
 
 
 
 
 
 
 
296
297	kfree(job->reply);
 
 
 
 
 
 
 
298}
299
 
 
 
 
 
 
 
 
300/**
301 * bsg_setup_queue - Create and add the bsg hooks so we can receive requests
302 * @dev: device to attach bsg device to
303 * @name: device to give bsg device
 
304 * @job_fn: bsg job handler
 
305 * @dd_job_size: size of LLD data needed for each job
306 * @release: @dev release function
307 */
308struct request_queue *bsg_setup_queue(struct device *dev, const char *name,
309		bsg_job_fn *job_fn, int dd_job_size,
310		void (*release)(struct device *))
311{
 
 
312	struct request_queue *q;
313	int ret;
314
315	q = blk_alloc_queue(GFP_KERNEL);
316	if (!q)
317		return ERR_PTR(-ENOMEM);
318	q->cmd_size = sizeof(struct bsg_job) + dd_job_size;
319	q->init_rq_fn = bsg_init_rq;
320	q->exit_rq_fn = bsg_exit_rq;
321	q->initialize_rq_fn = bsg_initialize_rq;
322	q->request_fn = bsg_request_fn;
323
324	ret = blk_init_allocated_queue(q);
325	if (ret)
326		goto out_cleanup_queue;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
327
328	q->queuedata = dev;
329	q->bsg_job_fn = job_fn;
330	blk_queue_flag_set(QUEUE_FLAG_BIDI, q);
331	blk_queue_softirq_done(q, bsg_softirq_done);
332	blk_queue_rq_timeout(q, BLK_DEFAULT_SG_TIMEOUT);
333
334	ret = bsg_register_queue(q, dev, name, &bsg_transport_ops, release);
335	if (ret) {
336		printk(KERN_ERR "%s: bsg interface failed to "
337		       "initialize - register queue\n", dev->kobj.name);
338		goto out_cleanup_queue;
339	}
340
341	return q;
342out_cleanup_queue:
343	blk_cleanup_queue(q);
 
 
 
 
 
344	return ERR_PTR(ret);
345}
346EXPORT_SYMBOL_GPL(bsg_setup_queue);
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  BSG helper library
  4 *
  5 *  Copyright (C) 2008   James Smart, Emulex Corporation
  6 *  Copyright (C) 2011   Red Hat, Inc.  All rights reserved.
  7 *  Copyright (C) 2011   Mike Christie
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  8 */
  9#include <linux/bsg.h>
 10#include <linux/slab.h>
 11#include <linux/blk-mq.h>
 12#include <linux/delay.h>
 13#include <linux/scatterlist.h>
 14#include <linux/bsg-lib.h>
 15#include <linux/export.h>
 16#include <scsi/scsi_cmnd.h>
 17#include <scsi/sg.h>
 18
 19#define uptr64(val) ((void __user *)(uintptr_t)(val))
 20
 21struct bsg_set {
 22	struct blk_mq_tag_set	tag_set;
 23	struct bsg_device	*bd;
 24	bsg_job_fn		*job_fn;
 25	bsg_timeout_fn		*timeout_fn;
 26};
 27
 28static int bsg_transport_sg_io_fn(struct request_queue *q, struct sg_io_v4 *hdr,
 29		bool open_for_write, unsigned int timeout)
 30{
 31	struct bsg_job *job;
 32	struct request *rq;
 33	struct bio *bio;
 34	void *reply;
 35	int ret;
 36
 37	if (hdr->protocol != BSG_PROTOCOL_SCSI  ||
 38	    hdr->subprotocol != BSG_SUB_PROTOCOL_SCSI_TRANSPORT)
 39		return -EINVAL;
 40	if (!capable(CAP_SYS_RAWIO))
 41		return -EPERM;
 
 
 42
 43	rq = blk_mq_alloc_request(q, hdr->dout_xfer_len ?
 44			     REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
 45	if (IS_ERR(rq))
 46		return PTR_ERR(rq);
 47	rq->timeout = timeout;
 48
 49	job = blk_mq_rq_to_pdu(rq);
 50	reply = job->reply;
 51	memset(job, 0, sizeof(*job));
 52	job->reply = reply;
 53	job->reply_len = SCSI_SENSE_BUFFERSIZE;
 54	job->dd_data = job + 1;
 55
 56	job->request_len = hdr->request_len;
 57	job->request = memdup_user(uptr64(hdr->request), hdr->request_len);
 58	if (IS_ERR(job->request)) {
 59		ret = PTR_ERR(job->request);
 60		goto out_free_rq;
 61	}
 62
 63	if (hdr->dout_xfer_len && hdr->din_xfer_len) {
 64		job->bidi_rq = blk_mq_alloc_request(rq->q, REQ_OP_DRV_IN, 0);
 65		if (IS_ERR(job->bidi_rq)) {
 66			ret = PTR_ERR(job->bidi_rq);
 67			goto out_free_job_request;
 68		}
 69
 70		ret = blk_rq_map_user(rq->q, job->bidi_rq, NULL,
 71				uptr64(hdr->din_xferp), hdr->din_xfer_len,
 72				GFP_KERNEL);
 73		if (ret)
 74			goto out_free_bidi_rq;
 75
 76		job->bidi_bio = job->bidi_rq->bio;
 77	} else {
 78		job->bidi_rq = NULL;
 79		job->bidi_bio = NULL;
 80	}
 81
 82	ret = 0;
 83	if (hdr->dout_xfer_len) {
 84		ret = blk_rq_map_user(rq->q, rq, NULL, uptr64(hdr->dout_xferp),
 85				hdr->dout_xfer_len, GFP_KERNEL);
 86	} else if (hdr->din_xfer_len) {
 87		ret = blk_rq_map_user(rq->q, rq, NULL, uptr64(hdr->din_xferp),
 88				hdr->din_xfer_len, GFP_KERNEL);
 89	}
 90
 91	if (ret)
 92		goto out_unmap_bidi_rq;
 93
 94	bio = rq->bio;
 95	blk_execute_rq(rq, !(hdr->flags & BSG_FLAG_Q_AT_TAIL));
 96
 97	/*
 98	 * The assignments below don't make much sense, but are kept for
 99	 * bug by bug backwards compatibility:
100	 */
101	hdr->device_status = job->result & 0xff;
102	hdr->transport_status = host_byte(job->result);
103	hdr->driver_status = 0;
104	hdr->info = 0;
105	if (hdr->device_status || hdr->transport_status || hdr->driver_status)
106		hdr->info |= SG_INFO_CHECK;
107	hdr->response_len = 0;
108
109	if (job->result < 0) {
110		/* we're only returning the result field in the reply */
111		job->reply_len = sizeof(u32);
112		ret = job->result;
113	}
114
115	if (job->reply_len && hdr->response) {
116		int len = min(hdr->max_response_len, job->reply_len);
117
118		if (copy_to_user(uptr64(hdr->response), job->reply, len))
119			ret = -EFAULT;
120		else
121			hdr->response_len = len;
122	}
123
124	/* we assume all request payload was transferred, residual == 0 */
125	hdr->dout_resid = 0;
126
127	if (job->bidi_rq) {
128		unsigned int rsp_len = job->reply_payload.payload_len;
129
130		if (WARN_ON(job->reply_payload_rcv_len > rsp_len))
131			hdr->din_resid = 0;
132		else
133			hdr->din_resid = rsp_len - job->reply_payload_rcv_len;
134	} else {
135		hdr->din_resid = 0;
136	}
137
138	blk_rq_unmap_user(bio);
139out_unmap_bidi_rq:
140	if (job->bidi_rq)
141		blk_rq_unmap_user(job->bidi_bio);
142out_free_bidi_rq:
143	if (job->bidi_rq)
144		blk_mq_free_request(job->bidi_rq);
145out_free_job_request:
146	kfree(job->request);
147out_free_rq:
148	blk_mq_free_request(rq);
149	return ret;
150}
151
 
 
 
 
 
 
 
152/**
153 * bsg_teardown_job - routine to teardown a bsg job
154 * @kref: kref inside bsg_job that is to be torn down
155 */
156static void bsg_teardown_job(struct kref *kref)
157{
158	struct bsg_job *job = container_of(kref, struct bsg_job, kref);
159	struct request *rq = blk_mq_rq_from_pdu(job);
160
161	put_device(job->dev);	/* release reference for the request */
162
163	kfree(job->request_payload.sg_list);
164	kfree(job->reply_payload.sg_list);
165
166	blk_mq_end_request(rq, BLK_STS_OK);
167}
168
169void bsg_job_put(struct bsg_job *job)
170{
171	kref_put(&job->kref, bsg_teardown_job);
172}
173EXPORT_SYMBOL_GPL(bsg_job_put);
174
175int bsg_job_get(struct bsg_job *job)
176{
177	return kref_get_unless_zero(&job->kref);
178}
179EXPORT_SYMBOL_GPL(bsg_job_get);
180
181/**
182 * bsg_job_done - completion routine for bsg requests
183 * @job: bsg_job that is complete
184 * @result: job reply result
185 * @reply_payload_rcv_len: length of payload recvd
186 *
187 * The LLD should call this when the bsg job has completed.
188 */
189void bsg_job_done(struct bsg_job *job, int result,
190		  unsigned int reply_payload_rcv_len)
191{
192	struct request *rq = blk_mq_rq_from_pdu(job);
193
194	job->result = result;
195	job->reply_payload_rcv_len = reply_payload_rcv_len;
196	if (likely(!blk_should_fake_timeout(rq->q)))
197		blk_mq_complete_request(rq);
198}
199EXPORT_SYMBOL_GPL(bsg_job_done);
200
201/**
202 * bsg_complete - softirq done routine for destroying the bsg requests
203 * @rq: BSG request that holds the job to be destroyed
204 */
205static void bsg_complete(struct request *rq)
206{
207	struct bsg_job *job = blk_mq_rq_to_pdu(rq);
208
209	bsg_job_put(job);
210}
211
212static int bsg_map_buffer(struct bsg_buffer *buf, struct request *req)
213{
214	size_t sz = (sizeof(struct scatterlist) * req->nr_phys_segments);
215
216	BUG_ON(!req->nr_phys_segments);
217
218	buf->sg_list = kmalloc(sz, GFP_KERNEL);
219	if (!buf->sg_list)
220		return -ENOMEM;
221	sg_init_table(buf->sg_list, req->nr_phys_segments);
222	buf->sg_cnt = blk_rq_map_sg(req->q, req, buf->sg_list);
223	buf->payload_len = blk_rq_bytes(req);
224	return 0;
225}
226
227/**
228 * bsg_prepare_job - create the bsg_job structure for the bsg request
229 * @dev: device that is being sent the bsg request
230 * @req: BSG request that needs a job structure
231 */
232static bool bsg_prepare_job(struct device *dev, struct request *req)
233{
 
234	struct bsg_job *job = blk_mq_rq_to_pdu(req);
235	int ret;
236
237	job->timeout = req->timeout;
238
239	if (req->bio) {
240		ret = bsg_map_buffer(&job->request_payload, req);
241		if (ret)
242			goto failjob_rls_job;
243	}
244	if (job->bidi_rq) {
245		ret = bsg_map_buffer(&job->reply_payload, job->bidi_rq);
246		if (ret)
247			goto failjob_rls_rqst_payload;
248	}
249	job->dev = dev;
250	/* take a reference for the request */
251	get_device(job->dev);
252	kref_init(&job->kref);
253	return true;
254
255failjob_rls_rqst_payload:
256	kfree(job->request_payload.sg_list);
257failjob_rls_job:
258	job->result = -ENOMEM;
259	return false;
260}
261
262/**
263 * bsg_queue_rq - generic handler for bsg requests
264 * @hctx: hardware queue
265 * @bd: queue data
266 *
267 * On error the create_bsg_job function should return a -Exyz error value
268 * that will be set to ->result.
269 *
270 * Drivers/subsys should pass this to the queue init function.
271 */
272static blk_status_t bsg_queue_rq(struct blk_mq_hw_ctx *hctx,
273				 const struct blk_mq_queue_data *bd)
 
274{
275	struct request_queue *q = hctx->queue;
276	struct device *dev = q->queuedata;
277	struct request *req = bd->rq;
278	struct bsg_set *bset =
279		container_of(q->tag_set, struct bsg_set, tag_set);
280	blk_status_t sts = BLK_STS_IOERR;
281	int ret;
282
283	blk_mq_start_request(req);
284
285	if (!get_device(dev))
286		return BLK_STS_IOERR;
287
288	if (!bsg_prepare_job(dev, req))
289		goto out;
 
 
 
 
 
 
 
 
 
290
291	ret = bset->job_fn(blk_mq_rq_to_pdu(req));
292	if (!ret)
293		sts = BLK_STS_OK;
 
 
294
295out:
296	put_device(dev);
297	return sts;
298}
299
300/* called right after the request is allocated for the request_queue */
301static int bsg_init_rq(struct blk_mq_tag_set *set, struct request *req,
302		       unsigned int hctx_idx, unsigned int numa_node)
303{
304	struct bsg_job *job = blk_mq_rq_to_pdu(req);
305
306	job->reply = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_KERNEL);
307	if (!job->reply)
308		return -ENOMEM;
309	return 0;
310}
311
312static void bsg_exit_rq(struct blk_mq_tag_set *set, struct request *req,
313		       unsigned int hctx_idx)
314{
315	struct bsg_job *job = blk_mq_rq_to_pdu(req);
 
316
317	kfree(job->reply);
 
 
 
318}
319
320void bsg_remove_queue(struct request_queue *q)
321{
322	if (q) {
323		struct bsg_set *bset =
324			container_of(q->tag_set, struct bsg_set, tag_set);
325
326		bsg_unregister_queue(bset->bd);
327		blk_mq_destroy_queue(q);
328		blk_put_queue(q);
329		blk_mq_free_tag_set(&bset->tag_set);
330		kfree(bset);
331	}
332}
333EXPORT_SYMBOL_GPL(bsg_remove_queue);
334
335static enum blk_eh_timer_return bsg_timeout(struct request *rq)
336{
337	struct bsg_set *bset =
338		container_of(rq->q->tag_set, struct bsg_set, tag_set);
339
340	if (!bset->timeout_fn)
341		return BLK_EH_DONE;
342	return bset->timeout_fn(rq);
343}
344
345static const struct blk_mq_ops bsg_mq_ops = {
346	.queue_rq		= bsg_queue_rq,
347	.init_request		= bsg_init_rq,
348	.exit_request		= bsg_exit_rq,
349	.complete		= bsg_complete,
350	.timeout		= bsg_timeout,
351};
352
353/**
354 * bsg_setup_queue - Create and add the bsg hooks so we can receive requests
355 * @dev: device to attach bsg device to
356 * @name: device to give bsg device
357 * @lim: queue limits for the bsg queue
358 * @job_fn: bsg job handler
359 * @timeout: timeout handler function pointer
360 * @dd_job_size: size of LLD data needed for each job
 
361 */
362struct request_queue *bsg_setup_queue(struct device *dev, const char *name,
363		struct queue_limits *lim, bsg_job_fn *job_fn,
364		bsg_timeout_fn *timeout, int dd_job_size)
365{
366	struct bsg_set *bset;
367	struct blk_mq_tag_set *set;
368	struct request_queue *q;
369	int ret = -ENOMEM;
370
371	bset = kzalloc(sizeof(*bset), GFP_KERNEL);
372	if (!bset)
373		return ERR_PTR(-ENOMEM);
 
 
 
 
 
374
375	bset->job_fn = job_fn;
376	bset->timeout_fn = timeout;
377
378	set = &bset->tag_set;
379	set->ops = &bsg_mq_ops;
380	set->nr_hw_queues = 1;
381	set->queue_depth = 128;
382	set->numa_node = NUMA_NO_NODE;
383	set->cmd_size = sizeof(struct bsg_job) + dd_job_size;
384	set->flags = BLK_MQ_F_NO_SCHED | BLK_MQ_F_BLOCKING;
385	if (blk_mq_alloc_tag_set(set))
386		goto out_tag_set;
387
388	q = blk_mq_alloc_queue(set, lim, dev);
389	if (IS_ERR(q)) {
390		ret = PTR_ERR(q);
391		goto out_queue;
392	}
393
 
 
 
 
394	blk_queue_rq_timeout(q, BLK_DEFAULT_SG_TIMEOUT);
395
396	bset->bd = bsg_register_queue(q, dev, name, bsg_transport_sg_io_fn);
397	if (IS_ERR(bset->bd)) {
398		ret = PTR_ERR(bset->bd);
 
399		goto out_cleanup_queue;
400	}
401
402	return q;
403out_cleanup_queue:
404	blk_mq_destroy_queue(q);
405	blk_put_queue(q);
406out_queue:
407	blk_mq_free_tag_set(set);
408out_tag_set:
409	kfree(bset);
410	return ERR_PTR(ret);
411}
412EXPORT_SYMBOL_GPL(bsg_setup_queue);