mirror of
https://github.com/torvalds/linux.git
synced 2024-11-22 20:22:09 +00:00
scsi: bsg: Move the whole request execution into the SCSI/transport handlers
Remove the amount of indirect calls by making the handler responsible for the entire execution of the request. Link: https://lore.kernel.org/r/20210729064845.1044147-5-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Christoph Hellwig
Martin K. Petersen
parent
1e61c1a804
commit
75ca56409e
@ -25,32 +25,39 @@ struct bsg_set {
|
||||
bsg_timeout_fn *timeout_fn;
|
||||
};
|
||||
|
||||
static int bsg_transport_check_proto(struct sg_io_v4 *hdr)
|
||||
static int bsg_transport_sg_io_fn(struct request_queue *q, struct sg_io_v4 *hdr,
|
||||
fmode_t mode, unsigned int timeout)
|
||||
{
|
||||
struct bsg_job *job;
|
||||
struct request *rq;
|
||||
struct bio *bio;
|
||||
int ret;
|
||||
|
||||
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;
|
||||
rq = blk_get_request(q, hdr->dout_xfer_len ?
|
||||
REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
|
||||
if (IS_ERR(rq))
|
||||
return PTR_ERR(rq);
|
||||
rq->timeout = timeout;
|
||||
|
||||
job = blk_mq_rq_to_pdu(rq);
|
||||
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 (IS_ERR(job->request)) {
|
||||
ret = PTR_ERR(job->request);
|
||||
goto out_put_request;
|
||||
}
|
||||
|
||||
if (hdr->dout_xfer_len && hdr->din_xfer_len) {
|
||||
job->bidi_rq = blk_get_request(rq->q, REQ_OP_DRV_IN, 0);
|
||||
if (IS_ERR(job->bidi_rq)) {
|
||||
ret = PTR_ERR(job->bidi_rq);
|
||||
goto out;
|
||||
goto out_free_job_request;
|
||||
}
|
||||
|
||||
ret = blk_rq_map_user(rq->q, job->bidi_rq, NULL,
|
||||
@ -65,20 +72,19 @@ static int bsg_transport_fill_hdr(struct request *rq, struct sg_io_v4 *hdr,
|
||||
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;
|
||||
if (hdr->dout_xfer_len) {
|
||||
ret = blk_rq_map_user(rq->q, rq, NULL, uptr64(hdr->dout_xferp),
|
||||
hdr->dout_xfer_len, GFP_KERNEL);
|
||||
} else if (hdr->din_xfer_len) {
|
||||
ret = blk_rq_map_user(rq->q, rq, NULL, uptr64(hdr->din_xferp),
|
||||
hdr->din_xfer_len, GFP_KERNEL);
|
||||
}
|
||||
|
||||
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;
|
||||
if (ret)
|
||||
goto out_unmap_bidi_rq;
|
||||
|
||||
bio = rq->bio;
|
||||
blk_execute_rq(NULL, rq, !(hdr->flags & BSG_FLAG_Q_AT_TAIL));
|
||||
|
||||
/*
|
||||
* The assignments below don't make much sense, but are kept for
|
||||
@ -121,28 +127,20 @@ static int bsg_transport_complete_rq(struct request *rq, struct sg_io_v4 *hdr)
|
||||
hdr->din_resid = 0;
|
||||
}
|
||||
|
||||
blk_rq_unmap_user(bio);
|
||||
out_unmap_bidi_rq:
|
||||
if (job->bidi_rq)
|
||||
blk_rq_unmap_user(job->bidi_bio);
|
||||
out_free_bidi_rq:
|
||||
if (job->bidi_rq)
|
||||
blk_put_request(job->bidi_rq);
|
||||
out_free_job_request:
|
||||
kfree(job->request);
|
||||
out_put_request:
|
||||
blk_put_request(rq);
|
||||
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
|
||||
@ -398,7 +396,7 @@ struct request_queue *bsg_setup_queue(struct device *dev, const char *name,
|
||||
q->queuedata = dev;
|
||||
blk_queue_rq_timeout(q, BLK_DEFAULT_SG_TIMEOUT);
|
||||
|
||||
bset->bd = bsg_register_queue(q, dev, name, &bsg_transport_ops);
|
||||
bset->bd = bsg_register_queue(q, dev, name, bsg_transport_sg_io_fn);
|
||||
if (IS_ERR(bset->bd)) {
|
||||
ret = PTR_ERR(bset->bd);
|
||||
goto out_cleanup_queue;
|
||||
|
||||
66
block/bsg.c
66
block/bsg.c
@ -22,12 +22,12 @@
|
||||
|
||||
struct bsg_device {
|
||||
struct request_queue *queue;
|
||||
const struct bsg_ops *ops;
|
||||
struct device device;
|
||||
struct cdev cdev;
|
||||
int max_queue;
|
||||
unsigned int timeout;
|
||||
unsigned int reserved_size;
|
||||
bsg_sg_io_fn *sg_io_fn;
|
||||
};
|
||||
|
||||
static inline struct bsg_device *to_bsg_device(struct inode *inode)
|
||||
@ -42,63 +42,28 @@ static DEFINE_IDA(bsg_minor_ida);
|
||||
static struct class *bsg_class;
|
||||
static int bsg_major;
|
||||
|
||||
#define uptr64(val) ((void __user *)(uintptr_t)(val))
|
||||
static unsigned int bsg_timeout(struct bsg_device *bd, struct sg_io_v4 *hdr)
|
||||
{
|
||||
unsigned int timeout = BLK_DEFAULT_SG_TIMEOUT;
|
||||
|
||||
if (hdr->timeout)
|
||||
timeout = msecs_to_jiffies(hdr->timeout);
|
||||
else if (bd->timeout)
|
||||
timeout = bd->timeout;
|
||||
|
||||
return max_t(unsigned int, timeout, BLK_MIN_SG_TIMEOUT);
|
||||
}
|
||||
|
||||
static int bsg_sg_io(struct bsg_device *bd, fmode_t mode, void __user *uarg)
|
||||
{
|
||||
struct request *rq;
|
||||
struct bio *bio;
|
||||
struct sg_io_v4 hdr;
|
||||
int ret;
|
||||
|
||||
if (copy_from_user(&hdr, uarg, sizeof(hdr)))
|
||||
return -EFAULT;
|
||||
|
||||
if (hdr.guard != 'Q')
|
||||
return -EINVAL;
|
||||
ret = bd->ops->check_proto(&hdr);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
rq = blk_get_request(bd->queue, hdr.dout_xfer_len ?
|
||||
REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
|
||||
if (IS_ERR(rq))
|
||||
return PTR_ERR(rq);
|
||||
|
||||
ret = bd->ops->fill_hdr(rq, &hdr, mode);
|
||||
if (ret) {
|
||||
blk_put_request(rq);
|
||||
return ret;
|
||||
}
|
||||
|
||||
rq->timeout = msecs_to_jiffies(hdr.timeout);
|
||||
if (!rq->timeout)
|
||||
rq->timeout = bd->timeout;
|
||||
if (!rq->timeout)
|
||||
rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
|
||||
if (rq->timeout < BLK_MIN_SG_TIMEOUT)
|
||||
rq->timeout = BLK_MIN_SG_TIMEOUT;
|
||||
|
||||
if (hdr.dout_xfer_len) {
|
||||
ret = blk_rq_map_user(rq->q, rq, NULL, uptr64(hdr.dout_xferp),
|
||||
hdr.dout_xfer_len, GFP_KERNEL);
|
||||
} else if (hdr.din_xfer_len) {
|
||||
ret = blk_rq_map_user(rq->q, rq, NULL, uptr64(hdr.din_xferp),
|
||||
hdr.din_xfer_len, GFP_KERNEL);
|
||||
}
|
||||
|
||||
if (ret)
|
||||
goto out_free_rq;
|
||||
|
||||
bio = rq->bio;
|
||||
|
||||
blk_execute_rq(NULL, rq, !(hdr.flags & BSG_FLAG_Q_AT_TAIL));
|
||||
ret = bd->ops->complete_rq(rq, &hdr);
|
||||
blk_rq_unmap_user(bio);
|
||||
|
||||
out_free_rq:
|
||||
bd->ops->free_rq(rq);
|
||||
blk_put_request(rq);
|
||||
ret = bd->sg_io_fn(bd->queue, &hdr, mode, bsg_timeout(bd, &hdr));
|
||||
if (!ret && copy_to_user(uarg, &hdr, sizeof(hdr)))
|
||||
return -EFAULT;
|
||||
return ret;
|
||||
@ -211,8 +176,7 @@ void bsg_unregister_queue(struct bsg_device *bd)
|
||||
EXPORT_SYMBOL_GPL(bsg_unregister_queue);
|
||||
|
||||
struct bsg_device *bsg_register_queue(struct request_queue *q,
|
||||
struct device *parent, const char *name,
|
||||
const struct bsg_ops *ops)
|
||||
struct device *parent, const char *name, bsg_sg_io_fn *sg_io_fn)
|
||||
{
|
||||
struct bsg_device *bd;
|
||||
int ret;
|
||||
@ -223,7 +187,7 @@ struct bsg_device *bsg_register_queue(struct request_queue *q,
|
||||
bd->max_queue = BSG_DEFAULT_CMDS;
|
||||
bd->reserved_size = INT_MAX;
|
||||
bd->queue = q;
|
||||
bd->ops = ops;
|
||||
bd->sg_io_fn = sg_io_fn;
|
||||
|
||||
ret = ida_simple_get(&bsg_minor_ida, 0, BSG_MAX_DEVS, GFP_KERNEL);
|
||||
if (ret < 0) {
|
||||
|
||||
@ -9,42 +9,57 @@
|
||||
|
||||
#define uptr64(val) ((void __user *)(uintptr_t)(val))
|
||||
|
||||
static int scsi_bsg_check_proto(struct sg_io_v4 *hdr)
|
||||
static int scsi_bsg_sg_io_fn(struct request_queue *q, struct sg_io_v4 *hdr,
|
||||
fmode_t mode, unsigned int timeout)
|
||||
{
|
||||
struct scsi_request *sreq;
|
||||
struct request *rq;
|
||||
struct bio *bio;
|
||||
int ret;
|
||||
|
||||
if (hdr->protocol != BSG_PROTOCOL_SCSI ||
|
||||
hdr->subprotocol != BSG_SUB_PROTOCOL_SCSI_CMD)
|
||||
return -EINVAL;
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int scsi_bsg_fill_hdr(struct request *rq, struct sg_io_v4 *hdr,
|
||||
fmode_t mode)
|
||||
{
|
||||
struct scsi_request *sreq = scsi_req(rq);
|
||||
|
||||
if (hdr->dout_xfer_len && hdr->din_xfer_len) {
|
||||
pr_warn_once("BIDI support in bsg has been removed.\n");
|
||||
return -EOPNOTSUPP;
|
||||
}
|
||||
|
||||
rq = blk_get_request(q, hdr->dout_xfer_len ?
|
||||
REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
|
||||
if (IS_ERR(rq))
|
||||
return PTR_ERR(rq);
|
||||
rq->timeout = timeout;
|
||||
|
||||
ret = -ENOMEM;
|
||||
sreq = scsi_req(rq);
|
||||
sreq->cmd_len = hdr->request_len;
|
||||
if (sreq->cmd_len > BLK_MAX_CDB) {
|
||||
sreq->cmd = kzalloc(sreq->cmd_len, GFP_KERNEL);
|
||||
if (!sreq->cmd)
|
||||
return -ENOMEM;
|
||||
goto out_put_request;
|
||||
}
|
||||
|
||||
ret = -EFAULT;
|
||||
if (copy_from_user(sreq->cmd, uptr64(hdr->request), sreq->cmd_len))
|
||||
return -EFAULT;
|
||||
goto out_free_cmd;
|
||||
ret = -EPERM;
|
||||
if (!scsi_cmd_allowed(sreq->cmd, mode))
|
||||
return -EPERM;
|
||||
return 0;
|
||||
goto out_free_cmd;
|
||||
|
||||
if (hdr->dout_xfer_len) {
|
||||
ret = blk_rq_map_user(rq->q, rq, NULL, uptr64(hdr->dout_xferp),
|
||||
hdr->dout_xfer_len, GFP_KERNEL);
|
||||
} else if (hdr->din_xfer_len) {
|
||||
ret = blk_rq_map_user(rq->q, rq, NULL, uptr64(hdr->din_xferp),
|
||||
hdr->din_xfer_len, GFP_KERNEL);
|
||||
}
|
||||
|
||||
static int scsi_bsg_complete_rq(struct request *rq, struct sg_io_v4 *hdr)
|
||||
{
|
||||
struct scsi_request *sreq = scsi_req(rq);
|
||||
int ret = 0;
|
||||
if (ret)
|
||||
goto out_free_cmd;
|
||||
|
||||
bio = rq->bio;
|
||||
blk_execute_rq(NULL, rq, !(hdr->flags & BSG_FLAG_Q_AT_TAIL));
|
||||
|
||||
/*
|
||||
* fill in all the output members
|
||||
@ -74,23 +89,17 @@ static int scsi_bsg_complete_rq(struct request *rq, struct sg_io_v4 *hdr)
|
||||
else
|
||||
hdr->dout_resid = sreq->resid_len;
|
||||
|
||||
blk_rq_unmap_user(bio);
|
||||
|
||||
out_free_cmd:
|
||||
scsi_req_free_cmd(scsi_req(rq));
|
||||
out_put_request:
|
||||
blk_put_request(rq);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static void scsi_bsg_free_rq(struct request *rq)
|
||||
{
|
||||
scsi_req_free_cmd(scsi_req(rq));
|
||||
}
|
||||
|
||||
static const struct bsg_ops scsi_bsg_ops = {
|
||||
.check_proto = scsi_bsg_check_proto,
|
||||
.fill_hdr = scsi_bsg_fill_hdr,
|
||||
.complete_rq = scsi_bsg_complete_rq,
|
||||
.free_rq = scsi_bsg_free_rq,
|
||||
};
|
||||
|
||||
struct bsg_device *scsi_bsg_register_queue(struct scsi_device *sdev)
|
||||
{
|
||||
return bsg_register_queue(sdev->request_queue, &sdev->sdev_gendev,
|
||||
dev_name(&sdev->sdev_gendev), &scsi_bsg_ops);
|
||||
dev_name(&sdev->sdev_gendev), scsi_bsg_sg_io_fn);
|
||||
}
|
||||
|
||||
@ -6,20 +6,14 @@
|
||||
|
||||
struct bsg_device;
|
||||
struct device;
|
||||
struct request;
|
||||
struct request_queue;
|
||||
|
||||
struct bsg_ops {
|
||||
int (*check_proto)(struct sg_io_v4 *hdr);
|
||||
int (*fill_hdr)(struct request *rq, struct sg_io_v4 *hdr,
|
||||
fmode_t mode);
|
||||
int (*complete_rq)(struct request *rq, struct sg_io_v4 *hdr);
|
||||
void (*free_rq)(struct request *rq);
|
||||
};
|
||||
typedef int (bsg_sg_io_fn)(struct request_queue *, struct sg_io_v4 *hdr,
|
||||
fmode_t mode, unsigned int timeout);
|
||||
|
||||
struct bsg_device *bsg_register_queue(struct request_queue *q,
|
||||
struct device *parent, const char *name,
|
||||
const struct bsg_ops *ops);
|
||||
bsg_sg_io_fn *sg_io_fn);
|
||||
void bsg_unregister_queue(struct bsg_device *bcd);
|
||||
|
||||
#endif /* _LINUX_BSG_H */
|
||||
|
||||
Loading…
Reference in New Issue
Block a user