[PATCH 1/9] btrfs: get rid of trivial __btrfs_lookup_bio_sums() wrappers

Omar Sandoval
2019-12-03T01:34:36Z

From: Omar Sandoval <osandov@fb.com>

Currently, we have two wrappers for __btrfs_lookup_bio_sums():
btrfs_lookup_bio_sums_dio(), which is used for direct I/O, and
btrfs_lookup_bio_sums(), which is used everywhere else. The only
difference is that the _dio variant looks up csums starting at the given
offset instead of using the page index, which isn't actually direct
I/O-specific. Let's clean up the signature and return value of
__btrfs_lookup_bio_sums(), rename it to btrfs_lookup_bio_sums(), and get
rid of the trivial helpers.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
---
fs/btrfs/compression.c | 4 ++--
fs/btrfs/ctree.h | 4 +---
fs/btrfs/file-item.c | 35 +++++++++++++++++------------------
fs/btrfs/inode.c | 6 +++---
4 files changed, 23 insertions(+), 26 deletions(-)

diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index ee834ef7beb4..03eb50727038 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -758,7 +758,7 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,

if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
ret = btrfs_lookup_bio_sums(inode, comp_bio,
- sums);
+ false, 0, sums);
BUG_ON(ret); /* -ENOMEM */
}

@@ -786,7 +786,7 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
BUG_ON(ret); /* -ENOMEM */

if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
- ret = btrfs_lookup_bio_sums(inode, comp_bio, sums);
+ ret = btrfs_lookup_bio_sums(inode, comp_bio, false, 0, sums);
BUG_ON(ret); /* -ENOMEM */
}

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index b2e8fd8a8e59..5ad45171e482 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2789,9 +2789,7 @@ struct btrfs_dio_private;
int btrfs_del_csums(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info, u64 bytenr, u64 len);
blk_status_t btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio,
- u8 *dst);
-blk_status_t btrfs_lookup_bio_sums_dio(struct inode *inode, struct bio *bio,
- u64 logical_offset);
+ bool at_offset, u64 offset, u8 *dst);
int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 objectid, u64 pos,
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index 3270a40b0777..b001ad073d16 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -148,8 +148,21 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
return ret;
}

-static blk_status_t __btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio,
- u64 logical_offset, u8 *dst, int dio)
+/**
+ * btrfs_lookup_bio_sums - Look up checksums for a bio.
+ * @inode: inode that the bio is for.
+ * @bio: bio embedded in btrfs_io_bio.
+ * @at_offset: If true, look up checksums for the extent at @offset.
+ * If false, use the page offsets from the bio.
+ * @offset: If @at_offset is true, offset in file to look up checksums for.
+ * Ignored otherwise.
+ * @dst: Buffer of size btrfs_super_csum_size() used to return checksum. If
+ * NULL, the checksum is returned in btrfs_io_bio(bio)->csum instead.
+ *
+ * Return: BLK_STS_RESOURCE if allocating memory fails, BLK_STS_OK otherwise.
+ */
+blk_status_t btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio,
+ bool at_offset, u64 offset, u8 *dst)
{
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct bio_vec bvec;
@@ -159,7 +172,6 @@ static blk_status_t __btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio
struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
struct btrfs_path *path;
u8 *csum;
- u64 offset = 0;
u64 item_start_offset = 0;
u64 item_last_offset = 0;
u64 disk_bytenr;
@@ -205,15 +217,13 @@ static blk_status_t __btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio
}

disk_bytenr = (u64)bio->bi_iter.bi_sector << 9;
- if (dio)
- offset = logical_offset;

bio_for_each_segment(bvec, bio, iter) {
page_bytes_left = bvec.bv_len;
if (count)
goto next;

- if (!dio)
+ if (!at_offset)
offset = page_offset(bvec.bv_page) + bvec.bv_offset;
count = btrfs_find_ordered_sum(inode, offset, disk_bytenr,
csum, nblocks);
@@ -285,18 +295,7 @@ static blk_status_t __btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio

WARN_ON_ONCE(count);
btrfs_free_path(path);
- return 0;
-}
-
-blk_status_t btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio,
- u8 *dst)
-{
- return __btrfs_lookup_bio_sums(inode, bio, 0, dst, 0);
-}
-
-blk_status_t btrfs_lookup_bio_sums_dio(struct inode *inode, struct bio *bio, u64 offset)
-{
- return __btrfs_lookup_bio_sums(inode, bio, offset, NULL, 1);
+ return BLK_STS_OK;
}

int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end,
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index e3c76645cad7..1fe4e5ec7907 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2128,7 +2128,7 @@ static blk_status_t btrfs_submit_bio_hook(struct inode *inode, struct bio *bio,
bio_flags);
goto out;
} else if (!skip_sum) {
- ret = btrfs_lookup_bio_sums(inode, bio, NULL);
+ ret = btrfs_lookup_bio_sums(inode, bio, false, 0, NULL);
if (ret)
goto out;
}
@@ -8356,8 +8356,8 @@ static inline blk_status_t btrfs_lookup_and_bind_dio_csum(struct inode *inode,
* contention.
*/
if (dip->logical_offset == file_offset) {
- ret = btrfs_lookup_bio_sums_dio(inode, dip->orig_bio,
- file_offset);
+ ret = btrfs_lookup_bio_sums(inode, dip->orig_bio, true,
+ file_offset, NULL);
if (ret)
return ret;
}
--
2.24.0