tmp_suning_uos_patched/block/bsg-lib.c
Christoph Hellwig a497ee34a4 block: switch all files cleared marked as GPLv2 or later to SPDX tags
All these files have some form of the usual GPLv2 or later boilerplate.
Switch them to use SPDX tags instead.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-30 16:11:59 -06:00

410 lines
9.8 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* BSG helper library
*
* Copyright (C) 2008 James Smart, Emulex Corporation
* Copyright (C) 2011 Red Hat, Inc. All rights reserved.
* Copyright (C) 2011 Mike Christie
*/
#include <linux/slab.h>
#include <linux/blk-mq.h>
#include <linux/delay.h>
#include <linux/scatterlist.h>
#include <linux/bsg-lib.h>
#include <linux/export.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/sg.h>
#define uptr64(val) ((void __user *)(uintptr_t)(val))
struct bsg_set {
struct blk_mq_tag_set tag_set;
bsg_job_fn *job_fn;
bsg_timeout_fn *timeout_fn;
};
static int bsg_transport_check_proto(struct sg_io_v4 *hdr)
{
if (hdr->protocol != BSG_PROTOCOL_SCSI ||
hdr->subprotocol != BSG_SUB_PROTOCOL_SCSI_TRANSPORT)
return -EINVAL;
if (!capable(CAP_SYS_RAWIO))
return -EPERM;
return 0;
}
static int bsg_transport_fill_hdr(struct request *rq, struct sg_io_v4 *hdr,
fmode_t mode)
{
struct bsg_job *job = blk_mq_rq_to_pdu(rq);
int ret;
job->request_len = hdr->request_len;
job->request = memdup_user(uptr64(hdr->request), hdr->request_len);
if (IS_ERR(job->request))
return PTR_ERR(job->request);
if (hdr->dout_xfer_len && hdr->din_xfer_len) {
job->bidi_rq = blk_get_request(rq->q, REQ_OP_SCSI_IN, 0);
if (IS_ERR(job->bidi_rq)) {
ret = PTR_ERR(job->bidi_rq);
goto out;
}
ret = blk_rq_map_user(rq->q, job->bidi_rq, NULL,
uptr64(hdr->din_xferp), hdr->din_xfer_len,
GFP_KERNEL);
if (ret)
goto out_free_bidi_rq;
job->bidi_bio = job->bidi_rq->bio;
} else {
job->bidi_rq = NULL;
job->bidi_bio = NULL;
}
return 0;
out_free_bidi_rq:
if (job->bidi_rq)
blk_put_request(job->bidi_rq);
out:
kfree(job->request);
return ret;
}
static int bsg_transport_complete_rq(struct request *rq, struct sg_io_v4 *hdr)
{
struct bsg_job *job = blk_mq_rq_to_pdu(rq);
int ret = 0;
/*
* The assignments below don't make much sense, but are kept for
* bug by bug backwards compatibility:
*/
hdr->device_status = job->result & 0xff;
hdr->transport_status = host_byte(job->result);
hdr->driver_status = driver_byte(job->result);
hdr->info = 0;
if (hdr->device_status || hdr->transport_status || hdr->driver_status)
hdr->info |= SG_INFO_CHECK;
hdr->response_len = 0;
if (job->result < 0) {
/* we're only returning the result field in the reply */
job->reply_len = sizeof(u32);
ret = job->result;
}
if (job->reply_len && hdr->response) {
int len = min(hdr->max_response_len, job->reply_len);
if (copy_to_user(uptr64(hdr->response), job->reply, len))
ret = -EFAULT;
else
hdr->response_len = len;
}
/* we assume all request payload was transferred, residual == 0 */
hdr->dout_resid = 0;
if (job->bidi_rq) {
unsigned int rsp_len = job->reply_payload.payload_len;
if (WARN_ON(job->reply_payload_rcv_len > rsp_len))
hdr->din_resid = 0;
else
hdr->din_resid = rsp_len - job->reply_payload_rcv_len;
} else {
hdr->din_resid = 0;
}
return ret;
}
static void bsg_transport_free_rq(struct request *rq)
{
struct bsg_job *job = blk_mq_rq_to_pdu(rq);
if (job->bidi_rq) {
blk_rq_unmap_user(job->bidi_bio);
blk_put_request(job->bidi_rq);
}
kfree(job->request);
}
static const struct bsg_ops bsg_transport_ops = {
.check_proto = bsg_transport_check_proto,
.fill_hdr = bsg_transport_fill_hdr,
.complete_rq = bsg_transport_complete_rq,
.free_rq = bsg_transport_free_rq,
};
/**
* bsg_teardown_job - routine to teardown a bsg job
* @kref: kref inside bsg_job that is to be torn down
*/
static void bsg_teardown_job(struct kref *kref)
{
struct bsg_job *job = container_of(kref, struct bsg_job, kref);
struct request *rq = blk_mq_rq_from_pdu(job);
put_device(job->dev); /* release reference for the request */
kfree(job->request_payload.sg_list);
kfree(job->reply_payload.sg_list);
blk_mq_end_request(rq, BLK_STS_OK);
}
void bsg_job_put(struct bsg_job *job)
{
kref_put(&job->kref, bsg_teardown_job);
}
EXPORT_SYMBOL_GPL(bsg_job_put);
int bsg_job_get(struct bsg_job *job)
{
return kref_get_unless_zero(&job->kref);
}
EXPORT_SYMBOL_GPL(bsg_job_get);
/**
* bsg_job_done - completion routine for bsg requests
* @job: bsg_job that is complete
* @result: job reply result
* @reply_payload_rcv_len: length of payload recvd
*
* The LLD should call this when the bsg job has completed.
*/
void bsg_job_done(struct bsg_job *job, int result,
unsigned int reply_payload_rcv_len)
{
job->result = result;
job->reply_payload_rcv_len = reply_payload_rcv_len;
blk_mq_complete_request(blk_mq_rq_from_pdu(job));
}
EXPORT_SYMBOL_GPL(bsg_job_done);
/**
* bsg_complete - softirq done routine for destroying the bsg requests
* @rq: BSG request that holds the job to be destroyed
*/
static void bsg_complete(struct request *rq)
{
struct bsg_job *job = blk_mq_rq_to_pdu(rq);
bsg_job_put(job);
}
static int bsg_map_buffer(struct bsg_buffer *buf, struct request *req)
{
size_t sz = (sizeof(struct scatterlist) * req->nr_phys_segments);
BUG_ON(!req->nr_phys_segments);
buf->sg_list = kzalloc(sz, GFP_KERNEL);
if (!buf->sg_list)
return -ENOMEM;
sg_init_table(buf->sg_list, req->nr_phys_segments);
buf->sg_cnt = blk_rq_map_sg(req->q, req, buf->sg_list);
buf->payload_len = blk_rq_bytes(req);
return 0;
}
/**
* bsg_prepare_job - create the bsg_job structure for the bsg request
* @dev: device that is being sent the bsg request
* @req: BSG request that needs a job structure
*/
static bool bsg_prepare_job(struct device *dev, struct request *req)
{
struct bsg_job *job = blk_mq_rq_to_pdu(req);
int ret;
job->timeout = req->timeout;
if (req->bio) {
ret = bsg_map_buffer(&job->request_payload, req);
if (ret)
goto failjob_rls_job;
}
if (job->bidi_rq) {
ret = bsg_map_buffer(&job->reply_payload, job->bidi_rq);
if (ret)
goto failjob_rls_rqst_payload;
}
job->dev = dev;
/* take a reference for the request */
get_device(job->dev);
kref_init(&job->kref);
return true;
failjob_rls_rqst_payload:
kfree(job->request_payload.sg_list);
failjob_rls_job:
job->result = -ENOMEM;
return false;
}
/**
* bsg_queue_rq - generic handler for bsg requests
* @hctx: hardware queue
* @bd: queue data
*
* On error the create_bsg_job function should return a -Exyz error value
* that will be set to ->result.
*
* Drivers/subsys should pass this to the queue init function.
*/
static blk_status_t bsg_queue_rq(struct blk_mq_hw_ctx *hctx,
const struct blk_mq_queue_data *bd)
{
struct request_queue *q = hctx->queue;
struct device *dev = q->queuedata;
struct request *req = bd->rq;
struct bsg_set *bset =
container_of(q->tag_set, struct bsg_set, tag_set);
int ret;
blk_mq_start_request(req);
if (!get_device(dev))
return BLK_STS_IOERR;
if (!bsg_prepare_job(dev, req))
return BLK_STS_IOERR;
ret = bset->job_fn(blk_mq_rq_to_pdu(req));
if (ret)
return BLK_STS_IOERR;
put_device(dev);
return BLK_STS_OK;
}
/* called right after the request is allocated for the request_queue */
static int bsg_init_rq(struct blk_mq_tag_set *set, struct request *req,
unsigned int hctx_idx, unsigned int numa_node)
{
struct bsg_job *job = blk_mq_rq_to_pdu(req);
job->reply = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_KERNEL);
if (!job->reply)
return -ENOMEM;
return 0;
}
/* called right before the request is given to the request_queue user */
static void bsg_initialize_rq(struct request *req)
{
struct bsg_job *job = blk_mq_rq_to_pdu(req);
void *reply = job->reply;
memset(job, 0, sizeof(*job));
job->reply = reply;
job->reply_len = SCSI_SENSE_BUFFERSIZE;
job->dd_data = job + 1;
}
static void bsg_exit_rq(struct blk_mq_tag_set *set, struct request *req,
unsigned int hctx_idx)
{
struct bsg_job *job = blk_mq_rq_to_pdu(req);
kfree(job->reply);
}
void bsg_remove_queue(struct request_queue *q)
{
if (q) {
struct bsg_set *bset =
container_of(q->tag_set, struct bsg_set, tag_set);
bsg_unregister_queue(q);
blk_cleanup_queue(q);
blk_mq_free_tag_set(&bset->tag_set);
kfree(bset);
}
}
EXPORT_SYMBOL_GPL(bsg_remove_queue);
static enum blk_eh_timer_return bsg_timeout(struct request *rq, bool reserved)
{
struct bsg_set *bset =
container_of(rq->q->tag_set, struct bsg_set, tag_set);
if (!bset->timeout_fn)
return BLK_EH_DONE;
return bset->timeout_fn(rq);
}
static const struct blk_mq_ops bsg_mq_ops = {
.queue_rq = bsg_queue_rq,
.init_request = bsg_init_rq,
.exit_request = bsg_exit_rq,
.initialize_rq_fn = bsg_initialize_rq,
.complete = bsg_complete,
.timeout = bsg_timeout,
};
/**
* bsg_setup_queue - Create and add the bsg hooks so we can receive requests
* @dev: device to attach bsg device to
* @name: device to give bsg device
* @job_fn: bsg job handler
* @dd_job_size: size of LLD data needed for each job
*/
struct request_queue *bsg_setup_queue(struct device *dev, const char *name,
bsg_job_fn *job_fn, bsg_timeout_fn *timeout, int dd_job_size)
{
struct bsg_set *bset;
struct blk_mq_tag_set *set;
struct request_queue *q;
int ret = -ENOMEM;
bset = kzalloc(sizeof(*bset), GFP_KERNEL);
if (!bset)
return ERR_PTR(-ENOMEM);
bset->job_fn = job_fn;
bset->timeout_fn = timeout;
set = &bset->tag_set;
set->ops = &bsg_mq_ops,
set->nr_hw_queues = 1;
set->queue_depth = 128;
set->numa_node = NUMA_NO_NODE;
set->cmd_size = sizeof(struct bsg_job) + dd_job_size;
set->flags = BLK_MQ_F_NO_SCHED | BLK_MQ_F_BLOCKING;
if (blk_mq_alloc_tag_set(set))
goto out_tag_set;
q = blk_mq_init_queue(set);
if (IS_ERR(q)) {
ret = PTR_ERR(q);
goto out_queue;
}
q->queuedata = dev;
blk_queue_rq_timeout(q, BLK_DEFAULT_SG_TIMEOUT);
ret = bsg_register_queue(q, dev, name, &bsg_transport_ops);
if (ret) {
printk(KERN_ERR "%s: bsg interface failed to "
"initialize - register queue\n", dev->kobj.name);
goto out_cleanup_queue;
}
return q;
out_cleanup_queue:
blk_cleanup_queue(q);
out_queue:
blk_mq_free_tag_set(set);
out_tag_set:
kfree(bset);
return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(bsg_setup_queue);