block: move request based cloning helpers to blk-mq.c

Keep all the request based code together.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20211117061404.331732-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig 2021-11-17 07:13:58 +01:00 committed by Jens Axboe
parent b84c5b50d3
commit 06c8c691e2
4 changed files with 185 additions and 187 deletions

View File

@ -594,7 +594,7 @@ static int __init setup_fail_make_request(char *str)
}
__setup("fail_make_request=", setup_fail_make_request);
static bool should_fail_request(struct block_device *part, unsigned int bytes)
bool should_fail_request(struct block_device *part, unsigned int bytes)
{
return part->bd_make_it_fail && should_fail(&fail_make_request, bytes);
}
@ -608,15 +608,6 @@ static int __init fail_make_request_debugfs(void)
}
late_initcall(fail_make_request_debugfs);
#else /* CONFIG_FAIL_MAKE_REQUEST */
static inline bool should_fail_request(struct block_device *part,
unsigned int bytes)
{
return false;
}
#endif /* CONFIG_FAIL_MAKE_REQUEST */
static inline bool bio_check_ro(struct bio *bio)
@ -1090,92 +1081,6 @@ int iocb_bio_iopoll(struct kiocb *kiocb, struct io_comp_batch *iob,
}
EXPORT_SYMBOL_GPL(iocb_bio_iopoll);
/**
* blk_cloned_rq_check_limits - Helper function to check a cloned request
* for the new queue limits
* @q: the queue
* @rq: the request being checked
*
* Description:
* @rq may have been made based on weaker limitations of upper-level queues
* in request stacking drivers, and it may violate the limitation of @q.
* Since the block layer and the underlying device driver trust @rq
* after it is inserted to @q, it should be checked against @q before
* the insertion using this generic function.
*
* Request stacking drivers like request-based dm may change the queue
* limits when retrying requests on other queues. Those requests need
* to be checked against the new queue limits again during dispatch.
*/
static blk_status_t blk_cloned_rq_check_limits(struct request_queue *q,
struct request *rq)
{
unsigned int max_sectors = blk_queue_get_max_sectors(q, req_op(rq));
if (blk_rq_sectors(rq) > max_sectors) {
/*
* SCSI device does not have a good way to return if
* Write Same/Zero is actually supported. If a device rejects
* a non-read/write command (discard, write same,etc.) the
* low-level device driver will set the relevant queue limit to
* 0 to prevent blk-lib from issuing more of the offending
* operations. Commands queued prior to the queue limit being
* reset need to be completed with BLK_STS_NOTSUPP to avoid I/O
* errors being propagated to upper layers.
*/
if (max_sectors == 0)
return BLK_STS_NOTSUPP;
printk(KERN_ERR "%s: over max size limit. (%u > %u)\n",
__func__, blk_rq_sectors(rq), max_sectors);
return BLK_STS_IOERR;
}
/*
* The queue settings related to segment counting may differ from the
* original queue.
*/
rq->nr_phys_segments = blk_recalc_rq_segments(rq);
if (rq->nr_phys_segments > queue_max_segments(q)) {
printk(KERN_ERR "%s: over max segments limit. (%hu > %hu)\n",
__func__, rq->nr_phys_segments, queue_max_segments(q));
return BLK_STS_IOERR;
}
return BLK_STS_OK;
}
/**
* blk_insert_cloned_request - Helper for stacking drivers to submit a request
* @q: the queue to submit the request
* @rq: the request being queued
*/
blk_status_t blk_insert_cloned_request(struct request_queue *q, struct request *rq)
{
blk_status_t ret;
ret = blk_cloned_rq_check_limits(q, rq);
if (ret != BLK_STS_OK)
return ret;
if (rq->rq_disk &&
should_fail_request(rq->rq_disk->part0, blk_rq_bytes(rq)))
return BLK_STS_IOERR;
if (blk_crypto_insert_cloned_request(rq))
return BLK_STS_IOERR;
blk_account_io_start(rq);
/*
* Since we have a scheduler attached on the top device,
* bypass a potential scheduler on the bottom device for
* insert.
*/
return blk_mq_request_issue_directly(rq, true);
}
EXPORT_SYMBOL_GPL(blk_insert_cloned_request);
static void update_io_ticks(struct block_device *part, unsigned long now,
bool end)
{
@ -1328,93 +1233,6 @@ int blk_lld_busy(struct request_queue *q)
}
EXPORT_SYMBOL_GPL(blk_lld_busy);
/**
* blk_rq_unprep_clone - Helper function to free all bios in a cloned request
* @rq: the clone request to be cleaned up
*
* Description:
* Free all bios in @rq for a cloned request.
*/
void blk_rq_unprep_clone(struct request *rq)
{
struct bio *bio;
while ((bio = rq->bio) != NULL) {
rq->bio = bio->bi_next;
bio_put(bio);
}
}
EXPORT_SYMBOL_GPL(blk_rq_unprep_clone);
/**
* blk_rq_prep_clone - Helper function to setup clone request
* @rq: the request to be setup
* @rq_src: original request to be cloned
* @bs: bio_set that bios for clone are allocated from
* @gfp_mask: memory allocation mask for bio
* @bio_ctr: setup function to be called for each clone bio.
* Returns %0 for success, non %0 for failure.
* @data: private data to be passed to @bio_ctr
*
* Description:
* Clones bios in @rq_src to @rq, and copies attributes of @rq_src to @rq.
* Also, pages which the original bios are pointing to are not copied
* and the cloned bios just point same pages.
* So cloned bios must be completed before original bios, which means
* the caller must complete @rq before @rq_src.
*/
int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
struct bio_set *bs, gfp_t gfp_mask,
int (*bio_ctr)(struct bio *, struct bio *, void *),
void *data)
{
struct bio *bio, *bio_src;
if (!bs)
bs = &fs_bio_set;
__rq_for_each_bio(bio_src, rq_src) {
bio = bio_clone_fast(bio_src, gfp_mask, bs);
if (!bio)
goto free_and_out;
if (bio_ctr && bio_ctr(bio, bio_src, data))
goto free_and_out;
if (rq->bio) {
rq->biotail->bi_next = bio;
rq->biotail = bio;
} else {
rq->bio = rq->biotail = bio;
}
bio = NULL;
}
/* Copy attributes of the original request to the clone request. */
rq->__sector = blk_rq_pos(rq_src);
rq->__data_len = blk_rq_bytes(rq_src);
if (rq_src->rq_flags & RQF_SPECIAL_PAYLOAD) {
rq->rq_flags |= RQF_SPECIAL_PAYLOAD;
rq->special_vec = rq_src->special_vec;
}
rq->nr_phys_segments = rq_src->nr_phys_segments;
rq->ioprio = rq_src->ioprio;
if (rq->bio && blk_crypto_rq_bio_prep(rq, rq->bio, gfp_mask) < 0)
goto free_and_out;
return 0;
free_and_out:
if (bio)
bio_put(bio);
blk_rq_unprep_clone(rq);
return -ENOMEM;
}
EXPORT_SYMBOL_GPL(blk_rq_prep_clone);
int kblockd_schedule_work(struct work_struct *work)
{
return queue_work(kblockd_workqueue, work);

View File

@ -2435,7 +2435,7 @@ static void blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
hctx_unlock(hctx, srcu_idx);
}
blk_status_t blk_mq_request_issue_directly(struct request *rq, bool last)
static blk_status_t blk_mq_request_issue_directly(struct request *rq, bool last)
{
blk_status_t ret;
int srcu_idx;
@ -2824,6 +2824,179 @@ void blk_mq_submit_bio(struct bio *bio)
}
}
/**
* blk_cloned_rq_check_limits - Helper function to check a cloned request
* for the new queue limits
* @q: the queue
* @rq: the request being checked
*
* Description:
* @rq may have been made based on weaker limitations of upper-level queues
* in request stacking drivers, and it may violate the limitation of @q.
* Since the block layer and the underlying device driver trust @rq
* after it is inserted to @q, it should be checked against @q before
* the insertion using this generic function.
*
* Request stacking drivers like request-based dm may change the queue
* limits when retrying requests on other queues. Those requests need
* to be checked against the new queue limits again during dispatch.
*/
static blk_status_t blk_cloned_rq_check_limits(struct request_queue *q,
struct request *rq)
{
unsigned int max_sectors = blk_queue_get_max_sectors(q, req_op(rq));
if (blk_rq_sectors(rq) > max_sectors) {
/*
* SCSI device does not have a good way to return if
* Write Same/Zero is actually supported. If a device rejects
* a non-read/write command (discard, write same,etc.) the
* low-level device driver will set the relevant queue limit to
* 0 to prevent blk-lib from issuing more of the offending
* operations. Commands queued prior to the queue limit being
* reset need to be completed with BLK_STS_NOTSUPP to avoid I/O
* errors being propagated to upper layers.
*/
if (max_sectors == 0)
return BLK_STS_NOTSUPP;
printk(KERN_ERR "%s: over max size limit. (%u > %u)\n",
__func__, blk_rq_sectors(rq), max_sectors);
return BLK_STS_IOERR;
}
/*
* The queue settings related to segment counting may differ from the
* original queue.
*/
rq->nr_phys_segments = blk_recalc_rq_segments(rq);
if (rq->nr_phys_segments > queue_max_segments(q)) {
printk(KERN_ERR "%s: over max segments limit. (%hu > %hu)\n",
__func__, rq->nr_phys_segments, queue_max_segments(q));
return BLK_STS_IOERR;
}
return BLK_STS_OK;
}
/**
* blk_insert_cloned_request - Helper for stacking drivers to submit a request
* @q: the queue to submit the request
* @rq: the request being queued
*/
blk_status_t blk_insert_cloned_request(struct request_queue *q, struct request *rq)
{
blk_status_t ret;
ret = blk_cloned_rq_check_limits(q, rq);
if (ret != BLK_STS_OK)
return ret;
if (rq->rq_disk &&
should_fail_request(rq->rq_disk->part0, blk_rq_bytes(rq)))
return BLK_STS_IOERR;
if (blk_crypto_insert_cloned_request(rq))
return BLK_STS_IOERR;
blk_account_io_start(rq);
/*
* Since we have a scheduler attached on the top device,
* bypass a potential scheduler on the bottom device for
* insert.
*/
return blk_mq_request_issue_directly(rq, true);
}
EXPORT_SYMBOL_GPL(blk_insert_cloned_request);
/**
* blk_rq_unprep_clone - Helper function to free all bios in a cloned request
* @rq: the clone request to be cleaned up
*
* Description:
* Free all bios in @rq for a cloned request.
*/
void blk_rq_unprep_clone(struct request *rq)
{
struct bio *bio;
while ((bio = rq->bio) != NULL) {
rq->bio = bio->bi_next;
bio_put(bio);
}
}
EXPORT_SYMBOL_GPL(blk_rq_unprep_clone);
/**
* blk_rq_prep_clone - Helper function to setup clone request
* @rq: the request to be setup
* @rq_src: original request to be cloned
* @bs: bio_set that bios for clone are allocated from
* @gfp_mask: memory allocation mask for bio
* @bio_ctr: setup function to be called for each clone bio.
* Returns %0 for success, non %0 for failure.
* @data: private data to be passed to @bio_ctr
*
* Description:
* Clones bios in @rq_src to @rq, and copies attributes of @rq_src to @rq.
* Also, pages which the original bios are pointing to are not copied
* and the cloned bios just point same pages.
* So cloned bios must be completed before original bios, which means
* the caller must complete @rq before @rq_src.
*/
int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
struct bio_set *bs, gfp_t gfp_mask,
int (*bio_ctr)(struct bio *, struct bio *, void *),
void *data)
{
struct bio *bio, *bio_src;
if (!bs)
bs = &fs_bio_set;
__rq_for_each_bio(bio_src, rq_src) {
bio = bio_clone_fast(bio_src, gfp_mask, bs);
if (!bio)
goto free_and_out;
if (bio_ctr && bio_ctr(bio, bio_src, data))
goto free_and_out;
if (rq->bio) {
rq->biotail->bi_next = bio;
rq->biotail = bio;
} else {
rq->bio = rq->biotail = bio;
}
bio = NULL;
}
/* Copy attributes of the original request to the clone request. */
rq->__sector = blk_rq_pos(rq_src);
rq->__data_len = blk_rq_bytes(rq_src);
if (rq_src->rq_flags & RQF_SPECIAL_PAYLOAD) {
rq->rq_flags |= RQF_SPECIAL_PAYLOAD;
rq->special_vec = rq_src->special_vec;
}
rq->nr_phys_segments = rq_src->nr_phys_segments;
rq->ioprio = rq_src->ioprio;
if (rq->bio && blk_crypto_rq_bio_prep(rq, rq->bio, gfp_mask) < 0)
goto free_and_out;
return 0;
free_and_out:
if (bio)
bio_put(bio);
blk_rq_unprep_clone(rq);
return -ENOMEM;
}
EXPORT_SYMBOL_GPL(blk_rq_prep_clone);
static size_t order_to_size(unsigned int order)
{
return (size_t)PAGE_SIZE << order;

View File

@ -65,9 +65,6 @@ void blk_mq_request_bypass_insert(struct request *rq, bool at_head,
bool run_queue);
void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
struct list_head *list);
/* Used by blk_insert_cloned_request() to issue request directly */
blk_status_t blk_mq_request_issue_directly(struct request *rq, bool last);
void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx,
struct list_head *list);

View File

@ -493,4 +493,14 @@ int disk_register_independent_access_ranges(struct gendisk *disk,
struct blk_independent_access_ranges *new_iars);
void disk_unregister_independent_access_ranges(struct gendisk *disk);
#ifdef CONFIG_FAIL_MAKE_REQUEST
bool should_fail_request(struct block_device *part, unsigned int bytes);
#else /* CONFIG_FAIL_MAKE_REQUEST */
static inline bool should_fail_request(struct block_device *part,
unsigned int bytes)
{
return false;
}
#endif /* CONFIG_FAIL_MAKE_REQUEST */
#endif /* BLK_INTERNAL_H */