From 378c18e5f024ac5a8aef4cb40d7c9aa9633d144c Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 16:30:35 +0200 Subject: Adding upstream version 2.38.1. Signed-off-by: Daniel Baumann --- libblkid/src/superblocks/bcache.c | 79 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 79 insertions(+) create mode 100644 libblkid/src/superblocks/bcache.c (limited to 'libblkid/src/superblocks/bcache.c') diff --git a/libblkid/src/superblocks/bcache.c b/libblkid/src/superblocks/bcache.c new file mode 100644 index 0000000..aa2dc04 --- /dev/null +++ b/libblkid/src/superblocks/bcache.c @@ -0,0 +1,79 @@ +/* + * 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 + */ + +#include +#include + +#include "superblocks.h" + +#define SB_LABEL_SIZE 32 +#define SB_JOURNAL_BUCKETS 256U + +#define node(i, j) ((i)->d + (j)) +#define end(i) node(i, le16_to_cpu((i)->keys)) + +/* + * The bcache_super_block is heavily simplified version of struct cache_sb in kernel. + * https://github.com/torvalds/linux/blob/master/include/uapi/linux/bcache.h + */ +struct bcache_super_block { + uint64_t csum; + uint64_t offset; /* where this super block was written */ + uint64_t version; + uint8_t magic[16]; /* bcache file system identifier */ + uint8_t uuid[16]; /* device identifier */ +}; + +/* magic string */ +#define BCACHE_SB_MAGIC "\xc6\x85\x73\xf6\x4e\x1a\x45\xca\x82\x65\xf5\x7f\x48\xba\x6d\x81" +/* magic string len */ +#define BCACHE_SB_MAGIC_LEN (sizeof(BCACHE_SB_MAGIC) - 1) +/* 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) + +static int probe_bcache (blkid_probe pr, const struct blkid_idmag *mag) +{ + struct bcache_super_block *bcs; + + bcs = blkid_probe_get_sb(pr, mag, struct bcache_super_block); + if (!bcs) + return errno ? -errno : BLKID_PROBE_NONE; + + if (le64_to_cpu(bcs->offset) != BCACHE_SB_OFF / 512) + return BLKID_PROBE_NONE; + + if (blkid_probe_set_uuid(pr, bcs->uuid) < 0) + return BLKID_PROBE_NONE; + + return BLKID_PROBE_OK; +} + +const struct blkid_idinfo bcache_idinfo = +{ + .name = "bcache", + .usage = BLKID_USAGE_OTHER, + .probefunc = probe_bcache, + .minsz = 8192, + .magics = + { + { + .magic = BCACHE_SB_MAGIC, + .len = BCACHE_SB_MAGIC_LEN, + .kboff = BCACHE_SB_KBOFF, + .sboff = BCACHE_SB_MAGIC_OFF + }, + { NULL } + } +}; + -- cgit v1.2.3