Commit e4581105 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe

block: rename __bio_add_pc_page to bio_add_hw_page

Rename __bio_add_pc_page() to bio_add_hw_page() and explicitly pass in a
max_sectors argument.

This max_sectors argument can be used to specify constraints from the
hardware.
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
[ jth: rebased and made public for blk-map.c ]
Signed-off-by: default avatarJohannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: default avatarDaniel Wagner <dwagner@suse.de>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 02992df8
......@@ -748,9 +748,14 @@ static inline bool page_is_mergeable(const struct bio_vec *bv,
return true;
}
static bool bio_try_merge_pc_page(struct request_queue *q, struct bio *bio,
struct page *page, unsigned len, unsigned offset,
bool *same_page)
/*
* Try to merge a page into a segment, while obeying the hardware segment
* size limit. This is not for normal read/write bios, but for passthrough
* or Zone Append operations that we can't split.
*/
static bool bio_try_merge_hw_seg(struct request_queue *q, struct bio *bio,
struct page *page, unsigned len,
unsigned offset, bool *same_page)
{
struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1];
unsigned long mask = queue_segment_boundary(q);
......@@ -765,38 +770,32 @@ static bool bio_try_merge_pc_page(struct request_queue *q, struct bio *bio,
}
/**
* __bio_add_pc_page - attempt to add page to passthrough bio
* @q: the target queue
* @bio: destination bio
* @page: page to add
* @len: vec entry length
* @offset: vec entry offset
* @same_page: return if the merge happen inside the same page
*
* Attempt to add a page to the bio_vec maplist. This can fail for a
* number of reasons, such as the bio being full or target block device
* limitations. The target block device must allow bio's up to PAGE_SIZE,
* so it is always possible to add a single page to an empty bio.
* bio_add_hw_page - attempt to add a page to a bio with hw constraints
* @q: the target queue
* @bio: destination bio
* @page: page to add
* @len: vec entry length
* @offset: vec entry offset
* @max_sectors: maximum number of sectors that can be added
* @same_page: return if the segment has been merged inside the same page
*
* This should only be used by passthrough bios.
* Add a page to a bio while respecting the hardware max_sectors, max_segment
* and gap limitations.
*/
int __bio_add_pc_page(struct request_queue *q, struct bio *bio,
int bio_add_hw_page(struct request_queue *q, struct bio *bio,
struct page *page, unsigned int len, unsigned int offset,
bool *same_page)
unsigned int max_sectors, bool *same_page)
{
struct bio_vec *bvec;
/*
* cloned bio must not modify vec list
*/
if (unlikely(bio_flagged(bio, BIO_CLONED)))
if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)))
return 0;
if (((bio->bi_iter.bi_size + len) >> 9) > queue_max_hw_sectors(q))
if (((bio->bi_iter.bi_size + len) >> 9) > max_sectors)
return 0;
if (bio->bi_vcnt > 0) {
if (bio_try_merge_pc_page(q, bio, page, len, offset, same_page))
if (bio_try_merge_hw_seg(q, bio, page, len, offset, same_page))
return len;
/*
......@@ -823,11 +822,27 @@ int __bio_add_pc_page(struct request_queue *q, struct bio *bio,
return len;
}
/**
* bio_add_pc_page - attempt to add page to passthrough bio
* @q: the target queue
* @bio: destination bio
* @page: page to add
* @len: vec entry length
* @offset: vec entry offset
*
* Attempt to add a page to the bio_vec maplist. This can fail for a
* number of reasons, such as the bio being full or target block device
* limitations. The target block device must allow bio's up to PAGE_SIZE,
* so it is always possible to add a single page to an empty bio.
*
* This should only be used by passthrough bios.
*/
int bio_add_pc_page(struct request_queue *q, struct bio *bio,
struct page *page, unsigned int len, unsigned int offset)
{
bool same_page = false;
return __bio_add_pc_page(q, bio, page, len, offset, &same_page);
return bio_add_hw_page(q, bio, page, len, offset,
queue_max_hw_sectors(q), &same_page);
}
EXPORT_SYMBOL(bio_add_pc_page);
......
......@@ -257,6 +257,7 @@ static struct bio *bio_copy_user_iov(struct request_queue *q,
static struct bio *bio_map_user_iov(struct request_queue *q,
struct iov_iter *iter, gfp_t gfp_mask)
{
unsigned int max_sectors = queue_max_hw_sectors(q);
int j;
struct bio *bio;
int ret;
......@@ -294,8 +295,8 @@ static struct bio *bio_map_user_iov(struct request_queue *q,
if (n > bytes)
n = bytes;
if (!__bio_add_pc_page(q, bio, page, n, offs,
&same_page)) {
if (!bio_add_hw_page(q, bio, page, n, offs,
max_sectors, &same_page)) {
if (same_page)
put_page(page);
break;
......
......@@ -452,8 +452,8 @@ static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
struct request_queue *__blk_alloc_queue(int node_id);
int __bio_add_pc_page(struct request_queue *q, struct bio *bio,
int bio_add_hw_page(struct request_queue *q, struct bio *bio,
struct page *page, unsigned int len, unsigned int offset,
bool *same_page);
unsigned int max_sectors, bool *same_page);
#endif /* BLK_INTERNAL_H */
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment