diff --git a/util-linux/volume_id/bcache.c b/util-linux/volume_id/bcache.c new file mode 100644 index 000000000..648e44de5 --- /dev/null +++ b/util-linux/volume_id/bcache.c @@ -0,0 +1,110 @@ +/* + * Copyright (C) 2013 Rolf Fokkens + * + * This file may be redistributed under the terms of the + * GNU Lesser General Public License. + * + * Based on code fragments from bcache-tools by Kent Overstreet: + * http://evilpiepirate.org/git/bcache-tools.git + */ + +//kbuild:lib-$(CONFIG_FEATURE_VOLUMEID_BCACHE) += bcache.o + +//config: +//config:config FEATURE_VOLUMEID_BCACHE +//config: bool "bcache filesystem" +//config: default y +//config: depends on VOLUMEID +//config: help +//config: TODO +//config: + +#include "volume_id_internal.h" + +#define SB_LABEL_SIZE 32 +#define SB_JOURNAL_BUCKETS 256U + +static const char bcache_magic[] = { + 0xc6, 0x85, 0x73, 0xf6, 0x4e, 0x1a, 0x45, 0xca, + 0x82, 0x65, 0xf5, 0x7f, 0x48, 0xba, 0x6d, 0x81 +}; + +struct bcache_super_block { + uint64_t csum; + uint64_t offset; /* sector where this sb was written */ + uint64_t version; + + uint8_t magic[16]; + + uint8_t uuid[16]; + union { + uint8_t set_uuid[16]; + uint64_t set_magic; + }; + uint8_t label[SB_LABEL_SIZE]; + + uint64_t flags; + uint64_t seq; + uint64_t pad[8]; + + union { + struct { + /* Cache devices */ + uint64_t nbuckets; /* device size */ + + uint16_t block_size; /* sectors */ + uint16_t bucket_size; /* sectors */ + + uint16_t nr_in_set; + uint16_t nr_this_dev; + }; + struct { + /* Backing devices */ + uint64_t 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 + */ + }; + }; + + uint32_t last_mount; /* time_t */ + + uint16_t first_bucket; + union { + uint16_t njournal_buckets; + uint16_t keys; + }; + uint64_t d[SB_JOURNAL_BUCKETS]; /* journal buckets */ +}; + +/* magic string */ +#define BCACHE_SB_MAGIC bcache_magic +/* magic string len */ +#define BCACHE_SB_MAGIC_LEN sizeof (bcache_magic) +/* super block offset */ +#define BCACHE_SB_OFF 0x1000 +/* supper block offset in kB */ +#define BCACHE_SB_KBOFF (BCACHE_SB_OFF >> 10) +/* magic string offset within super block */ +#define BCACHE_SB_MAGIC_OFF offsetof (struct bcache_super_block, magic) + +int FAST_FUNC volume_id_probe_bcache(struct volume_id *id /*,uint64_t off*/) +{ + struct bcache_super_block *sb; + + sb = volume_id_get_buffer(id, BCACHE_SB_OFF, sizeof(*sb)); + if (sb == NULL) + return -1; + + if (memcmp(sb->magic, BCACHE_SB_MAGIC, BCACHE_SB_MAGIC_LEN) != 0) + return -1; + + volume_id_set_label_string(id, sb->label, SB_LABEL_SIZE); + volume_id_set_uuid(id, sb->uuid, UUID_DCE); + IF_FEATURE_BLKID_TYPE(id->type = "bcache";) + + return 0; +} diff --git a/util-linux/volume_id/volume_id.c b/util-linux/volume_id/volume_id.c index 5c459a0e2..3f71e0084 100644 --- a/util-linux/volume_id/volume_id.c +++ b/util-linux/volume_id/volume_id.c @@ -107,6 +107,9 @@ static const probe_fptr fs1[] = { #if ENABLE_FEATURE_VOLUMEID_XFS volume_id_probe_xfs, #endif +#if ENABLE_FEATURE_VOLUMEID_BCACHE + volume_id_probe_bcache, +#endif }; /* fill buffer with maximum */ diff --git a/util-linux/volume_id/volume_id_internal.h b/util-linux/volume_id/volume_id_internal.h index 6e2dbd7bb..3061ac4d5 100644 --- a/util-linux/volume_id/volume_id_internal.h +++ b/util-linux/volume_id/volume_id_internal.h @@ -169,6 +169,8 @@ int FAST_FUNC volume_id_probe_linux_raid(struct volume_id *id /*,uint64_t off*/, /* FS */ +int FAST_FUNC volume_id_probe_bcache(struct volume_id *id /*,uint64_t off*/); + int FAST_FUNC volume_id_probe_btrfs(struct volume_id *id /*,uint64_t off*/); int FAST_FUNC volume_id_probe_cramfs(struct volume_id *id /*,uint64_t off*/);