block: move the bi_size update out of __bio_try_merge_page

The update of bi_size is the only thing in __bio_try_merge_page that
needs a bio.  Move it to the callers, and merge __bio_try_merge_page
and page_is_mergeable into a single bvec_try_merge_page that only takes
the current bvec instead of a full bio.  This will allow reusing this
function for supporting multi-page integrity payload bvecs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jinyoung Choi <j-young.choi@samsung.com>
Link: https://lore.kernel.org/r/20230724165433.117645-8-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig 2023-07-24 09:54:32 -07:00 committed by Jens Axboe
parent 80232b5203
commit 858c708d9e

View file

@ -903,9 +903,8 @@ static inline bool bio_full(struct bio *bio, unsigned len)
return false;
}
static inline bool page_is_mergeable(const struct bio_vec *bv,
struct page *page, unsigned int len, unsigned int off,
bool *same_page)
static bool bvec_try_merge_page(struct bio_vec *bv, struct page *page,
unsigned int len, unsigned int off, bool *same_page)
{
size_t bv_end = bv->bv_offset + bv->bv_len;
phys_addr_t vec_end_addr = page_to_phys(bv->bv_page) + bv_end - 1;
@ -919,38 +918,14 @@ static inline bool page_is_mergeable(const struct bio_vec *bv,
return false;
*same_page = ((vec_end_addr & PAGE_MASK) == page_addr);
if (*same_page)
return true;
else if (IS_ENABLED(CONFIG_KMSAN))
return false;
return (bv->bv_page + bv_end / PAGE_SIZE) == (page + off / PAGE_SIZE);
}
if (!*same_page) {
if (IS_ENABLED(CONFIG_KMSAN))
return false;
if (bv->bv_page + bv_end / PAGE_SIZE != page + off / PAGE_SIZE)
return false;
}
/**
* __bio_try_merge_page - try appending data to an existing bvec.
* @bio: destination bio
* @page: start page to add
* @len: length of the data to add
* @off: offset of the data relative to @page
* @same_page: return if the segment has been merged inside the same page
*
* Try to add the data at @page + @off to the last bvec of @bio. This is a
* useful optimisation for file systems with a block size smaller than the
* page size.
*
* Warn if (@len, @off) crosses pages in case that @same_page is true.
*
* Return %true on success or %false on failure.
*/
static bool __bio_try_merge_page(struct bio *bio, struct page *page,
unsigned int len, unsigned int off, bool *same_page)
{
struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1];
if (!page_is_mergeable(bv, page, len, off, same_page))
return false;
bv->bv_len += len;
bio->bi_iter.bi_size += len;
return true;
}
@ -972,7 +947,7 @@ static bool bio_try_merge_hw_seg(struct request_queue *q, struct bio *bio,
return false;
if (bv->bv_len + len > queue_max_segment_size(q))
return false;
return __bio_try_merge_page(bio, page, len, offset, same_page);
return bvec_try_merge_page(bv, page, len, offset, same_page);
}
/**
@ -1001,8 +976,11 @@ int bio_add_hw_page(struct request_queue *q, struct bio *bio,
return 0;
if (bio->bi_vcnt > 0) {
if (bio_try_merge_hw_seg(q, bio, page, len, offset, same_page))
if (bio_try_merge_hw_seg(q, bio, page, len, offset,
same_page)) {
bio->bi_iter.bi_size += len;
return len;
}
if (bio->bi_vcnt >=
min(bio->bi_max_vecs, queue_max_segments(q)))
@ -1123,8 +1101,11 @@ int bio_add_page(struct bio *bio, struct page *page,
return 0;
if (bio->bi_vcnt > 0 &&
__bio_try_merge_page(bio, page, len, offset, &same_page))
bvec_try_merge_page(&bio->bi_io_vec[bio->bi_vcnt - 1],
page, len, offset, &same_page)) {
bio->bi_iter.bi_size += len;
return len;
}
if (bio->bi_vcnt >= bio->bi_max_vecs)
return 0;
@ -1206,7 +1187,9 @@ static int bio_iov_add_page(struct bio *bio, struct page *page,
return -EIO;
if (bio->bi_vcnt > 0 &&
__bio_try_merge_page(bio, page, len, offset, &same_page)) {
bvec_try_merge_page(&bio->bi_io_vec[bio->bi_vcnt - 1],
page, len, offset, &same_page)) {
bio->bi_iter.bi_size += len;
if (same_page)
bio_release_page(bio, page);
return 0;