From a702a692cd7559053ea573f4e2c84828f0e62824 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 24 Jan 2020 01:01:27 +0800 Subject: [PATCH] bcache: use a separate data structure for the on-disk super block Split out an on-disk version struct cache_sb with the proper endianness annotations. This fixes a fair chunk of sparse warnings, but there are some left due to the way the checksum is defined. Signed-off-by: Christoph Hellwig Signed-off-by: Coly Li Signed-off-by: Jens Axboe --- drivers/md/bcache/super.c | 6 +++--- include/uapi/linux/bcache.h | 51 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 54 insertions(+), 3 deletions(-) diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index a573ce1d85aa..3045f27e0d67 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -63,14 +63,14 @@ static const char *read_super(struct cache_sb *sb, struct block_device *bdev, struct page **res) { const char *err; - struct cache_sb *s; + struct cache_sb_disk *s; struct buffer_head *bh = __bread(bdev, 1, SB_SIZE); unsigned int i; if (!bh) return "IO error"; - s = (struct cache_sb *) bh->b_data; + s = (struct cache_sb_disk *)bh->b_data; sb->offset = le64_to_cpu(s->offset); sb->version = le64_to_cpu(s->version); @@ -209,7 +209,7 @@ static void write_bdev_super_endio(struct bio *bio) static void __write_super(struct cache_sb *sb, struct bio *bio) { - struct cache_sb *out = page_address(bio_first_page_all(bio)); + struct cache_sb_disk *out = page_address(bio_first_page_all(bio)); unsigned int i; bio->bi_iter.bi_sector = SB_SECTOR; diff --git a/include/uapi/linux/bcache.h b/include/uapi/linux/bcache.h index 5d4f58e059fd..1d8b3a9fc080 100644 --- a/include/uapi/linux/bcache.h +++ b/include/uapi/linux/bcache.h @@ -156,6 +156,57 @@ static inline struct bkey *bkey_idx(const struct bkey *k, unsigned int nr_keys) #define BDEV_DATA_START_DEFAULT 16 /* sectors */ +struct cache_sb_disk { + __le64 csum; + __le64 offset; /* sector where this sb was written */ + __le64 version; + + __u8 magic[16]; + + __u8 uuid[16]; + union { + __u8 set_uuid[16]; + __le64 set_magic; + }; + __u8 label[SB_LABEL_SIZE]; + + __le64 flags; + __le64 seq; + __le64 pad[8]; + + union { + struct { + /* Cache devices */ + __le64 nbuckets; /* device size */ + + __le16 block_size; /* sectors */ + __le16 bucket_size; /* sectors */ + + __le16 nr_in_set; + __le16 nr_this_dev; + }; + struct { + /* Backing devices */ + __le64 data_offset; + + /* + * block_size from the cache device section is still used by + * backing devices, so don't add anything here until we fix + * things to not need it for backing devices anymore + */ + }; + }; + + __le32 last_mount; /* time overflow in y2106 */ + + __le16 first_bucket; + union { + __le16 njournal_buckets; + __le16 keys; + }; + __le64 d[SB_JOURNAL_BUCKETS]; /* journal buckets */ +}; + struct cache_sb { __u64 csum; __u64 offset; /* sector where this sb was written */ -- 2.11.0