btrfs: remove btrfs_bio_alloc() helper

The helper btrfs_bio_alloc() is almost the same as btrfs_io_bio_alloc(),
except it's allocating using BIO_MAX_VECS as @nr_iovecs, and initializes
bio->bi_iter.bi_sector.

However the naming itself is not using "btrfs_io_bio" to indicate its
parameter is "strcut btrfs_io_bio" and can be easily confused with
"struct btrfs_bio".

Considering assigned bio->bi_iter.bi_sector is such a simple work and
there are already tons of call sites doing that manually, there is no
need to do that in a helper.

Remove btrfs_bio_alloc() helper, and enhance btrfs_io_bio_alloc()
function to provide a fail-safe value for its @nr_iovecs.

And then replace all btrfs_bio_alloc() callers with
btrfs_io_bio_alloc().

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 9 insertions, 18 deletions

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 86190ce91323..55a04790df1c 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -3121,16 +3121,16 @@ static inline void btrfs_io_bio_init(struct btrfs_io_bio *btrfs_bio)
 }
 
 /*
- * The following helpers allocate a bio. As it's backed by a bioset, it'll
- * never fail.  We're returning a bio right now but you can call btrfs_io_bio
- * for the appropriate container_of magic
+ * Allocate a btrfs_io_bio, with @nr_iovecs as maximum number of iovecs.
+ *
+ * The bio allocation is backed by bioset and does not fail.
  */
-struct bio *btrfs_bio_alloc(u64 first_byte)
+struct bio *btrfs_io_bio_alloc(unsigned int nr_iovecs)
 {
 	struct bio *bio;
 
-	bio = bio_alloc_bioset(GFP_NOFS, BIO_MAX_VECS, &btrfs_bioset);
-	bio->bi_iter.bi_sector = first_byte >> 9;
+	ASSERT(0 < nr_iovecs && nr_iovecs <= BIO_MAX_VECS);
+	bio = bio_alloc_bioset(GFP_NOFS, nr_iovecs, &btrfs_bioset);
 	btrfs_io_bio_init(btrfs_io_bio(bio));
 	return bio;
 }
@@ -3148,16 +3148,6 @@ struct bio *btrfs_bio_clone(struct bio *bio)
 	return new;
 }
 
-struct bio *btrfs_io_bio_alloc(unsigned int nr_iovecs)
-{
-	struct bio *bio;
-
-	/* Bio allocation backed by a bioset does not fail */
-	bio = bio_alloc_bioset(GFP_NOFS, nr_iovecs, &btrfs_bioset);
-	btrfs_io_bio_init(btrfs_io_bio(bio));
-	return bio;
-}
-
 struct bio *btrfs_bio_clone_partial(struct bio *orig, u64 offset, u64 size)
 {
 	struct bio *bio;
@@ -3307,14 +3297,15 @@ static int alloc_new_bio(struct btrfs_inode *inode,
 	struct bio *bio;
 	int ret;
 
+	bio = btrfs_io_bio_alloc(BIO_MAX_VECS);
 	/*
 	 * For compressed page range, its disk_bytenr is always @disk_bytenr
 	 * passed in, no matter if we have added any range into previous bio.
 	 */
 	if (bio_flags & EXTENT_BIO_COMPRESSED)
-		bio = btrfs_bio_alloc(disk_bytenr);
+		bio->bi_iter.bi_sector = disk_bytenr >> SECTOR_SHIFT;
 	else
-		bio = btrfs_bio_alloc(disk_bytenr + offset);
+		bio->bi_iter.bi_sector = (disk_bytenr + offset) >> SECTOR_SHIFT;
 	bio_ctrl->bio = bio;
 	bio_ctrl->bio_flags = bio_flags;
 	bio->bi_end_io = end_io_func;