[PATCH v3 2/3] btrfs: remove btrfs_bio_alloc() helper
From: Qu Wenruo <hidden>
Date: 2021-09-15 07:17:27
Subsystem:
btrfs file system, filesystems (vfs and infrastructure), the rest · Maintainers:
Chris Mason, David Sterba, Alexander Viro, Christian Brauner, Linus Torvalds
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 initialize 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 <redacted> --- fs/btrfs/compression.c | 12 ++++++++---- fs/btrfs/extent_io.c | 33 +++++++++++++++------------------ fs/btrfs/extent_io.h | 1 - 3 files changed, 23 insertions(+), 23 deletions(-)
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 7869ad12bc6e..2475dc0b1c22 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c@@ -418,7 +418,8 @@ blk_status_t btrfs_submit_compressed_write(struct btrfs_inode *inode, u64 start, cb->orig_bio = NULL; cb->nr_pages = nr_pages; - bio = btrfs_bio_alloc(first_byte); + bio = btrfs_io_bio_alloc(0); + bio->bi_iter.bi_sector = first_byte >> SECTOR_SHIFT; bio->bi_opf = bio_op | write_flags; bio->bi_private = cb; bio->bi_end_io = end_compressed_bio_write;
@@ -490,7 +491,8 @@ blk_status_t btrfs_submit_compressed_write(struct btrfs_inode *inode, u64 start, bio_endio(bio); } - bio = btrfs_bio_alloc(first_byte); + bio = btrfs_io_bio_alloc(0); + bio->bi_iter.bi_sector = first_byte >> SECTOR_SHIFT; bio->bi_opf = bio_op | write_flags; bio->bi_private = cb; bio->bi_end_io = end_compressed_bio_write;
@@ -748,7 +750,8 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, /* include any pages we added in add_ra-bio_pages */ cb->len = bio->bi_iter.bi_size; - comp_bio = btrfs_bio_alloc(cur_disk_byte); + comp_bio = btrfs_io_bio_alloc(0); + comp_bio->bi_iter.bi_sector = cur_disk_byte >> SECTOR_SHIFT; comp_bio->bi_opf = REQ_OP_READ; comp_bio->bi_private = cb; comp_bio->bi_end_io = end_compressed_bio_read;
@@ -806,7 +809,8 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, bio_endio(comp_bio); } - comp_bio = btrfs_bio_alloc(cur_disk_byte); + comp_bio = btrfs_io_bio_alloc(0); + comp_bio->bi_iter.bi_sector = cur_disk_byte >> SECTOR_SHIFT; comp_bio->bi_opf = REQ_OP_READ; comp_bio->bi_private = cb; comp_bio->bi_end_io = end_compressed_bio_read;
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 1aed03ef5f49..d3fcf7e8dc48 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c@@ -3121,16 +3121,22 @@ 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 iovecs. + * + * If @nr_iovecs is 0, it will use BIO_MAX_VECS as @nr_iovces instead. + * This behavior is to provide a fail-safe default value. + * + * This helper uses bioset to allocate the bio, thus it's backed by mempool, + * and should not fail from process contexts. */ -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(nr_iovecs <= BIO_MAX_VECS); + if (nr_iovecs == 0) + 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 +3154,6 @@ 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 +3303,15 @@ static int alloc_new_bio(struct btrfs_inode *inode, struct bio *bio; int ret; + bio = btrfs_io_bio_alloc(0); /* * 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;
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index ba471f2063a7..81fa68eaa699 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h@@ -278,7 +278,6 @@ void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end); void extent_clear_unlock_delalloc(struct btrfs_inode *inode, u64 start, u64 end, struct page *locked_page, u32 bits_to_clear, unsigned long page_ops); -struct bio *btrfs_bio_alloc(u64 first_byte); struct bio *btrfs_io_bio_alloc(unsigned int nr_iovecs); struct bio *btrfs_bio_clone(struct bio *bio); struct bio *btrfs_bio_clone_partial(struct bio *orig, u64 offset, u64 size);
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2.33.0