block: remove bio_get_nr_vecs()

We can always fill up the bio now, no need to estimate the possible
size based on queue parameters.

Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
[hch: rebased and wrote a changelog]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Kent Overstreet 2015-05-19 14:31:01 +02:00 committed by Jens Axboe
parent 6cf66b4caf
commit b54ffb73ca
16 changed files with 18 additions and 74 deletions

View file

@ -693,29 +693,6 @@ struct bio *bio_clone_bioset(struct bio *bio_src, gfp_t gfp_mask,
}
EXPORT_SYMBOL(bio_clone_bioset);
/**
* bio_get_nr_vecs - return approx number of vecs
* @bdev: I/O target
*
* Return the approximate number of pages we can send to this target.
* There's no guarantee that you will be able to fit this number of pages
* into a bio, it does not account for dynamic restrictions that vary
* on offset.
*/
int bio_get_nr_vecs(struct block_device *bdev)
{
struct request_queue *q = bdev_get_queue(bdev);
int nr_pages;
nr_pages = min_t(unsigned,
queue_max_segments(q),
queue_max_sectors(q) / (PAGE_SIZE >> 9) + 1);
return min_t(unsigned, nr_pages, BIO_MAX_PAGES);
}
EXPORT_SYMBOL(bio_get_nr_vecs);
/**
* bio_add_pc_page - attempt to add page to bio
* @q: the target queue

View file

@ -316,7 +316,7 @@ static void do_region(int rw, unsigned region, struct dm_io_region *where,
if ((rw & REQ_DISCARD) || (rw & REQ_WRITE_SAME))
num_bvecs = 1;
else
num_bvecs = min_t(int, bio_get_nr_vecs(where->bdev),
num_bvecs = min_t(int, BIO_MAX_PAGES,
dm_sector_div_up(remaining, (PAGE_SIZE >> SECTOR_SHIFT)));
bio = bio_alloc_bioset(GFP_NOIO, num_bvecs, io->client->bios);

View file

@ -97,10 +97,7 @@ static inline int compressed_bio_size(struct btrfs_root *root,
static struct bio *compressed_bio_alloc(struct block_device *bdev,
u64 first_byte, gfp_t gfp_flags)
{
int nr_vecs;
nr_vecs = bio_get_nr_vecs(bdev);
return btrfs_bio_alloc(bdev, first_byte >> 9, nr_vecs, gfp_flags);
return btrfs_bio_alloc(bdev, first_byte >> 9, BIO_MAX_PAGES, gfp_flags);
}
static int check_compressed_csum(struct inode *inode,

View file

@ -2795,9 +2795,7 @@ static int submit_extent_page(int rw, struct extent_io_tree *tree,
{
int ret = 0;
struct bio *bio;
int nr;
int contig = 0;
int this_compressed = bio_flags & EXTENT_BIO_COMPRESSED;
int old_compressed = prev_bio_flags & EXTENT_BIO_COMPRESSED;
size_t page_size = min_t(size_t, size, PAGE_CACHE_SIZE);
@ -2822,12 +2820,9 @@ static int submit_extent_page(int rw, struct extent_io_tree *tree,
return 0;
}
}
if (this_compressed)
nr = BIO_MAX_PAGES;
else
nr = bio_get_nr_vecs(bdev);
bio = btrfs_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH);
bio = btrfs_bio_alloc(bdev, sector, BIO_MAX_PAGES,
GFP_NOFS | __GFP_HIGH);
if (!bio)
return -ENOMEM;

View file

@ -7959,8 +7959,7 @@ static void btrfs_end_dio_bio(struct bio *bio)
static struct bio *btrfs_dio_bio_alloc(struct block_device *bdev,
u64 first_sector, gfp_t gfp_flags)
{
int nr_vecs = bio_get_nr_vecs(bdev);
return btrfs_bio_alloc(bdev, first_sector, nr_vecs, gfp_flags);
return btrfs_bio_alloc(bdev, first_sector, BIO_MAX_PAGES, gfp_flags);
}
static inline int btrfs_lookup_and_bind_dio_csum(struct btrfs_root *root,

View file

@ -454,27 +454,14 @@ struct scrub_ctx *scrub_setup_ctx(struct btrfs_device *dev, int is_dev_replace)
struct scrub_ctx *sctx;
int i;
struct btrfs_fs_info *fs_info = dev->dev_root->fs_info;
int pages_per_rd_bio;
int ret;
/*
* the setting of pages_per_rd_bio is correct for scrub but might
* be wrong for the dev_replace code where we might read from
* different devices in the initial huge bios. However, that
* code is able to correctly handle the case when adding a page
* to a bio fails.
*/
if (dev->bdev)
pages_per_rd_bio = min_t(int, SCRUB_PAGES_PER_RD_BIO,
bio_get_nr_vecs(dev->bdev));
else
pages_per_rd_bio = SCRUB_PAGES_PER_RD_BIO;
sctx = kzalloc(sizeof(*sctx), GFP_NOFS);
if (!sctx)
goto nomem;
atomic_set(&sctx->refs, 1);
sctx->is_dev_replace = is_dev_replace;
sctx->pages_per_rd_bio = pages_per_rd_bio;
sctx->pages_per_rd_bio = SCRUB_PAGES_PER_RD_BIO;
sctx->curr = -1;
sctx->dev_root = dev->dev_root;
for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) {
@ -3896,8 +3883,7 @@ static int scrub_setup_wr_ctx(struct scrub_ctx *sctx,
return 0;
WARN_ON(!dev->bdev);
wr_ctx->pages_per_wr_bio = min_t(int, SCRUB_PAGES_PER_WR_BIO,
bio_get_nr_vecs(dev->bdev));
wr_ctx->pages_per_wr_bio = SCRUB_PAGES_PER_WR_BIO;
wr_ctx->tgtdev = dev;
atomic_set(&wr_ctx->flush_all_writes, 0);
return 0;

View file

@ -655,7 +655,7 @@ static inline int dio_new_bio(struct dio *dio, struct dio_submit *sdio,
if (ret)
goto out;
sector = start_sector << (sdio->blkbits - 9);
nr_pages = min(sdio->pages_in_io, bio_get_nr_vecs(map_bh->b_bdev));
nr_pages = min(sdio->pages_in_io, BIO_MAX_PAGES);
BUG_ON(nr_pages <= 0);
dio_bio_alloc(dio, sdio, map_bh->b_bdev, sector, nr_pages);
sdio->boundary = 0;

View file

@ -372,10 +372,9 @@ void ext4_io_submit_init(struct ext4_io_submit *io,
static int io_submit_init_bio(struct ext4_io_submit *io,
struct buffer_head *bh)
{
int nvecs = bio_get_nr_vecs(bh->b_bdev);
struct bio *bio;
bio = bio_alloc(GFP_NOIO, min(nvecs, BIO_MAX_PAGES));
bio = bio_alloc(GFP_NOIO, BIO_MAX_PAGES);
if (!bio)
return -ENOMEM;
bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);

View file

@ -284,7 +284,7 @@ int ext4_mpage_readpages(struct address_space *mapping,
goto set_error_page;
}
bio = bio_alloc(GFP_KERNEL,
min_t(int, nr_pages, bio_get_nr_vecs(bdev)));
min_t(int, nr_pages, BIO_MAX_PAGES));
if (!bio) {
if (ctx)
ext4_release_crypto_ctx(ctx);

View file

@ -1552,7 +1552,7 @@ static int f2fs_mpage_readpages(struct address_space *mapping,
}
bio = bio_alloc(GFP_KERNEL,
min_t(int, nr_pages, bio_get_nr_vecs(bdev)));
min_t(int, nr_pages, BIO_MAX_PAGES));
if (!bio) {
if (ctx)
f2fs_release_crypto_ctx(ctx);

View file

@ -261,18 +261,11 @@ void gfs2_log_flush_bio(struct gfs2_sbd *sdp, int rw)
static struct bio *gfs2_log_alloc_bio(struct gfs2_sbd *sdp, u64 blkno)
{
struct super_block *sb = sdp->sd_vfs;
unsigned nrvecs = bio_get_nr_vecs(sb->s_bdev);
struct bio *bio;
BUG_ON(sdp->sd_log_bio);
while (1) {
bio = bio_alloc(GFP_NOIO, nrvecs);
if (likely(bio))
break;
nrvecs = max(nrvecs/2, 1U);
}
bio = bio_alloc(GFP_NOIO, BIO_MAX_PAGES);
bio->bi_iter.bi_sector = blkno * (sb->s_blocksize >> 9);
bio->bi_bdev = sb->s_bdev;
bio->bi_end_io = gfs2_end_log_write;

View file

@ -81,7 +81,7 @@ static int __bdev_writeseg(struct super_block *sb, u64 ofs, pgoff_t index,
unsigned int max_pages;
int i;
max_pages = min(nr_pages, (size_t) bio_get_nr_vecs(super->s_bdev));
max_pages = min(nr_pages, BIO_MAX_PAGES);
bio = bio_alloc(GFP_NOFS, max_pages);
BUG_ON(!bio);
@ -171,7 +171,7 @@ static int do_erase(struct super_block *sb, u64 ofs, pgoff_t index,
unsigned int max_pages;
int i;
max_pages = min(nr_pages, (size_t) bio_get_nr_vecs(super->s_bdev));
max_pages = min(nr_pages, BIO_MAX_PAGES);
bio = bio_alloc(GFP_NOFS, max_pages);
BUG_ON(!bio);

View file

@ -277,7 +277,7 @@ do_mpage_readpage(struct bio *bio, struct page *page, unsigned nr_pages,
goto out;
}
bio = mpage_alloc(bdev, blocks[0] << (blkbits - 9),
min_t(int, nr_pages, bio_get_nr_vecs(bdev)),
min_t(int, nr_pages, BIO_MAX_PAGES),
GFP_KERNEL);
if (bio == NULL)
goto confused;
@ -602,7 +602,7 @@ static int __mpage_writepage(struct page *page, struct writeback_control *wbc,
}
}
bio = mpage_alloc(bdev, blocks[0] << (blkbits - 9),
bio_get_nr_vecs(bdev), GFP_NOFS|__GFP_HIGH);
BIO_MAX_PAGES, GFP_NOFS|__GFP_HIGH);
if (bio == NULL)
goto confused;

View file

@ -414,7 +414,7 @@ static void nilfs_segbuf_prepare_write(struct nilfs_segment_buffer *segbuf,
{
wi->bio = NULL;
wi->rest_blocks = segbuf->sb_sum.nblocks;
wi->max_pages = bio_get_nr_vecs(wi->nilfs->ns_bdev);
wi->max_pages = BIO_MAX_PAGES;
wi->nr_vecs = min(wi->max_pages, wi->rest_blocks);
wi->start = wi->end = 0;
wi->blocknr = segbuf->sb_pseg_start;

View file

@ -381,8 +381,7 @@ STATIC struct bio *
xfs_alloc_ioend_bio(
struct buffer_head *bh)
{
int nvecs = bio_get_nr_vecs(bh->b_bdev);
struct bio *bio = bio_alloc(GFP_NOIO, nvecs);
struct bio *bio = bio_alloc(GFP_NOIO, BIO_MAX_PAGES);
ASSERT(bio->bi_private == NULL);
bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);

View file

@ -460,7 +460,6 @@ void bio_chain(struct bio *, struct bio *);
extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
unsigned int, unsigned int);
extern int bio_get_nr_vecs(struct block_device *);
struct rq_map_data;
extern struct bio *bio_map_user_iov(struct request_queue *,
const struct iov_iter *, gfp_t);