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scsi/osd: open code blk_make_request 

I wish the OSD code could simply use blk_rq_map_* helpers like
everyone else, but the complex nature of deciding if we have
DATA IN and/or DATA OUT buffers might make this impossible
(at least for a mere human like me).

But using blk_rq_append_bio at least allows sharing the setup code
between request with or without dat a buffers, and given that this
is the last user of blk_make_request it allows getting rid of that
somewhat awkward interface.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Boaz Harrosh <ooo@electrozaur.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Christoph Hellwig 2016-07-19 11:31:53 +02:00 committed by Jens Axboe
parent dd9cf04611
commit 4613c5f1df
3 changed files with 16 additions and 68 deletions
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57
block/blk-core.c
View File

@ -1317,63 +1317,6 @@ struct request *blk_get_request(struct request_queue *q, int rw, gfp_t gfp_mask)
}
EXPORT_SYMBOL(blk_get_request);
/**
* blk_make_request - given a bio, allocate a corresponding struct request.
* @q: target request queue
* @bio: The bio describing the memory mappings that will be submitted for IO.
* It may be a chained-bio properly constructed by block/bio layer.
* @gfp_mask: gfp flags to be used for memory allocation
*
* blk_make_request is the parallel of generic_make_request for BLOCK_PC
* type commands. Where the struct request needs to be farther initialized by
* the caller. It is passed a &struct bio, which describes the memory info of
* the I/O transfer.
*
* The caller of blk_make_request must make sure that bi_io_vec
* are set to describe the memory buffers. That bio_data_dir() will return
* the needed direction of the request. (And all bio's in the passed bio-chain
* are properly set accordingly)
*
* If called under none-sleepable conditions, mapped bio buffers must not
* need bouncing, by calling the appropriate masked or flagged allocator,
* suitable for the target device. Otherwise the call to blk_queue_bounce will
* BUG.
*
* WARNING: When allocating/cloning a bio-chain, careful consideration should be
* given to how you allocate bios. In particular, you cannot use
* __GFP_DIRECT_RECLAIM for anything but the first bio in the chain. Otherwise
* you risk waiting for IO completion of a bio that hasn't been submitted yet,
* thus resulting in a deadlock. Alternatively bios should be allocated using
* bio_kmalloc() instead of bio_alloc(), as that avoids the mempool deadlock.
* If possible a big IO should be split into smaller parts when allocation
* fails. Partial allocation should not be an error, or you risk a live-lock.
*/
struct request *blk_make_request(struct request_queue *q, struct bio *bio,
gfp_t gfp_mask)
{
struct request *rq = blk_get_request(q, bio_data_dir(bio), gfp_mask);
if (IS_ERR(rq))
return rq;
blk_rq_set_block_pc(rq);
for_each_bio(bio) {
struct bio *bounce_bio = bio;
int ret;
blk_queue_bounce(q, &bounce_bio);
ret = blk_rq_append_bio(rq, bounce_bio);
if (unlikely(ret)) {
blk_put_request(rq);
return ERR_PTR(ret);
}
}
return rq;
}
EXPORT_SYMBOL(blk_make_request);
/**
* blk_rq_set_block_pc - initialize a request to type BLOCK_PC
* @rq: request to be initialized

25
drivers/scsi/osd/osd_initiator.c
View File

@ -1558,18 +1558,25 @@ static int _osd_req_finalize_data_integrity(struct osd_request *or,
static struct request *_make_request(struct request_queue *q, bool has_write,
struct _osd_io_info *oii, gfp_t flags)
{
if (oii->bio)
return blk_make_request(q, oii->bio, flags);
else {
struct request *req;
struct request *req;
struct bio *bio = oii->bio;
int ret;
req = blk_get_request(q, has_write ? WRITE : READ, flags);
if (IS_ERR(req))
return req;
blk_rq_set_block_pc(req);
req = blk_get_request(q, has_write ? WRITE : READ, flags);
if (IS_ERR(req))
return req;
blk_rq_set_block_pc(req);
for_each_bio(bio) {
struct bio *bounce_bio = bio;
blk_queue_bounce(req->q, &bounce_bio);
ret = blk_rq_append_bio(req, bounce_bio);
if (ret)
return ERR_PTR(ret);
}
return req;
}
static int _init_blk_request(struct osd_request *or,

2
include/linux/blkdev.h
View File

@ -788,8 +788,6 @@ extern void blk_rq_init(struct request_queue *q, struct request *rq);
extern void blk_put_request(struct request *);
extern void __blk_put_request(struct request_queue *, struct request *);
extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
extern struct request *blk_make_request(struct request_queue *, struct bio *,
gfp_t);
extern void blk_rq_set_block_pc(struct request *);
extern void blk_requeue_request(struct request_queue *, struct request *);
extern void blk_add_request_payload(struct request *rq, struct page *page,