From eb9054a32e22d04c8ff3c7521084c0632ed80e70 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Thu, 19 May 2011 20:25:14 -0700 Subject: [PATCH] Updates for backing devices --- bcache.h | 20 ++++++++++++++++---- make-bcache.c | 46 +++++++++++++++++++++++++--------------------- 2 files changed, 41 insertions(+), 25 deletions(-) diff --git a/bcache.h b/bcache.h index 3f94dce..deadbe3 100644 --- a/bcache.h +++ b/bcache.h @@ -5,24 +5,36 @@ static const char bcache_magic[] = { 0xc6, 0x85, 0x73, 0xf6, 0x4e, 0x1a, 0x45, 0xca, 0x82, 0x65, 0xf5, 0x7f, 0x48, 0xba, 0x6d, 0x81 }; +struct bkey { + uint64_t header; + uint64_t key; + uint64_t ptr[]; +}; + struct cache_sb { uint8_t magic[16]; + uint8_t uuid[16]; + uint8_t set_uuid[16]; + uint64_t sequence; + #define CACHE_CLEAN 1 #define CACHE_SYNC 2 -#define CACHE_BACKING_DEVICE 4 +#define CACHE_BACKING_DEV 4 uint32_t version; uint16_t block_size; /* sectors */ uint16_t bucket_size; /* sectors */ uint32_t journal_start; /* buckets */ uint32_t first_bucket; /* start of data */ uint64_t nbuckets; /* device size */ - uint64_t btree_root; + + union { + struct bkey btree_root; + uint64_t _pad[8]; + }; uint16_t btree_level; uint16_t nr_in_set; uint16_t nr_this_dev; uint16_t _pad[1]; - uint8_t uuid[16]; - uint8_t set_uuid[16]; }; struct bucket_disk { diff --git a/make-bcache.c b/make-bcache.c index b213f9e..02fe405 100644 --- a/make-bcache.c +++ b/make-bcache.c @@ -1,6 +1,6 @@ #define _FILE_OFFSET_BITS 64 #define __USE_FILE_OFFSET64 -#define _XOPEN_SOURCE 500 +#define _XOPEN_SOURCE 600 #include #include @@ -19,9 +19,9 @@ char zero[4096]; -long getblocks(int fd) +uint64_t getblocks(int fd) { - long ret; + uint64_t ret; struct stat statbuf; if (fstat(fd, &statbuf)) { perror("stat error\n"); @@ -36,10 +36,10 @@ long getblocks(int fd) return ret; } -long hatoi(const char *s) +uint64_t hatoi(const char *s) { char *e; - long long i = strtol(s, &e, 10); + long long i = strtoll(s, &e, 10); switch (*e) { case 't': case 'T': @@ -70,15 +70,17 @@ void usage() int main(int argc, char **argv) { bool cache = false, backingdev = false; - int64_t nblocks; + int64_t nblocks, journal = 0; int fd, i, c; - char uuid[40]; - struct cache_sb sb = { .block_size = 8, .bucket_size = 0 }; + char uuid[40], set_uuid[40]; + struct cache_sb sb; + + memset(&sb, 0, sizeof(struct cache_sb)); uuid_generate(sb.uuid); uuid_generate(sb.set_uuid); - while ((c = getopt(argc, argv, "CBU:w:b:")) != -1) + while ((c = getopt(argc, argv, "CBU:w:b:j:")) != -1) switch (c) { case 'C': cache = true; @@ -92,6 +94,9 @@ int main(int argc, char **argv) case 'w': sb.block_size = hatoi(optarg) / 512; break; + case 'j': + journal = atoi(optarg); + break; case 'U': if (uuid_parse(optarg, sb.uuid)) { printf("Bad uuid\n"); @@ -100,6 +105,9 @@ int main(int argc, char **argv) break; } + if (!sb.block_size) + sb.block_size = 4; + if (!sb.bucket_size) sb.bucket_size = cache ? 256 : 8192; @@ -119,7 +127,7 @@ int main(int argc, char **argv) exit(EXIT_FAILURE); } nblocks = getblocks(fd); - printf("device is %li sectors\n", nblocks); + printf("device is %ju sectors\n", nblocks); if (sb.bucket_size < sb.block_size || sb.bucket_size > nblocks / 8) { @@ -128,32 +136,28 @@ int main(int argc, char **argv) } memcpy(sb.magic, bcache_magic, 16); - sb.version = backingdev ? CACHE_BACKING_DEVICE : 0; + sb.version = backingdev ? CACHE_BACKING_DEV : 0; sb.nbuckets = nblocks / sb.bucket_size; sb.nr_in_set = 1; uuid_unparse(sb.uuid, uuid); + uuid_unparse(sb.set_uuid, set_uuid); - do - sb.first_bucket = ((--sb.nbuckets * sizeof(struct bucket_disk)) + (24 << 9)) / (sb.bucket_size << 9) + 1; - while ((sb.nbuckets + sb.first_bucket) * sb.bucket_size > nblocks); - - sb.journal_start = sb.first_bucket; - - sb.btree_root = sb.first_bucket * sb.bucket_size; - sb.btree_level = 0; + sb.journal_start = ((sb.nbuckets * sizeof(struct bucket_disk)) + (24 << 9)) / (sb.bucket_size << 9) + 1; + sb.first_bucket = sb.journal_start + journal; printf("block_size: %u\n" "bucket_size: %u\n" "journal_start: %u\n" "first_bucket: %u\n" "nbuckets: %ju\n" - "UUID: %s\n", + "UUID: %s\n" + "Set UUID: %s\n", sb.block_size, sb.bucket_size, sb.journal_start, sb.first_bucket, sb.nbuckets, - uuid); + uuid, set_uuid); /* Zero out priorities */ lseek(fd, 4096, SEEK_SET);