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-rw-r--r--drivers/md/bcache/bcache.h244
-rw-r--r--drivers/md/bcache/bset.c4
-rw-r--r--drivers/md/bcache/bset.h31
-rw-r--r--drivers/md/bcache/btree.c2
-rw-r--r--drivers/md/bcache/journal.c4
-rw-r--r--drivers/md/bcache/journal.h37
-rw-r--r--drivers/md/bcache/request.c9
-rw-r--r--drivers/md/bcache/super.c13
-rw-r--r--drivers/md/bcache/util.h10
-rw-r--r--include/uapi/linux/bcache.h373
10 files changed, 387 insertions, 340 deletions
diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index e32f6fd91755..045cb99f1ca6 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -177,6 +177,7 @@
#define pr_fmt(fmt) "bcache: %s() " fmt "\n", __func__
+#include <linux/bcache.h>
#include <linux/bio.h>
#include <linux/kobject.h>
#include <linux/list.h>
@@ -210,168 +211,6 @@ BITMASK(GC_MARK, struct bucket, gc_mark, 0, 2);
#define GC_MARK_METADATA 2
BITMASK(GC_SECTORS_USED, struct bucket, gc_mark, 2, 14);
-struct bkey {
- uint64_t high;
- uint64_t low;
- uint64_t ptr[];
-};
-
-/* Enough for a key with 6 pointers */
-#define BKEY_PAD 8
-
-#define BKEY_PADDED(key) \
- union { struct bkey key; uint64_t key ## _pad[BKEY_PAD]; }
-
-/* Version 0: Cache device
- * Version 1: Backing device
- * Version 2: Seed pointer into btree node checksum
- * Version 3: Cache device with new UUID format
- * Version 4: Backing device with data offset
- */
-#define BCACHE_SB_VERSION_CDEV 0
-#define BCACHE_SB_VERSION_BDEV 1
-#define BCACHE_SB_VERSION_CDEV_WITH_UUID 3
-#define BCACHE_SB_VERSION_BDEV_WITH_OFFSET 4
-#define BCACHE_SB_MAX_VERSION 4
-
-#define SB_SECTOR 8
-#define SB_SIZE 4096
-#define SB_LABEL_SIZE 32
-#define SB_JOURNAL_BUCKETS 256U
-/* SB_JOURNAL_BUCKETS must be divisible by BITS_PER_LONG */
-#define MAX_CACHES_PER_SET 8
-
-#define BDEV_DATA_START_DEFAULT 16 /* sectors */
-
-struct cache_sb {
- 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 */
-};
-
-BITMASK(CACHE_SYNC, struct cache_sb, flags, 0, 1);
-BITMASK(CACHE_DISCARD, struct cache_sb, flags, 1, 1);
-BITMASK(CACHE_REPLACEMENT, struct cache_sb, flags, 2, 3);
-#define CACHE_REPLACEMENT_LRU 0U
-#define CACHE_REPLACEMENT_FIFO 1U
-#define CACHE_REPLACEMENT_RANDOM 2U
-
-BITMASK(BDEV_CACHE_MODE, struct cache_sb, flags, 0, 4);
-#define CACHE_MODE_WRITETHROUGH 0U
-#define CACHE_MODE_WRITEBACK 1U
-#define CACHE_MODE_WRITEAROUND 2U
-#define CACHE_MODE_NONE 3U
-BITMASK(BDEV_STATE, struct cache_sb, flags, 61, 2);
-#define BDEV_STATE_NONE 0U
-#define BDEV_STATE_CLEAN 1U
-#define BDEV_STATE_DIRTY 2U
-#define BDEV_STATE_STALE 3U
-
-/* Version 1: Seed pointer into btree node checksum
- */
-#define BCACHE_BSET_VERSION 1
-
-/*
- * This is the on disk format for btree nodes - a btree node on disk is a list
- * of these; within each set the keys are sorted
- */
-struct bset {
- uint64_t csum;
- uint64_t magic;
- uint64_t seq;
- uint32_t version;
- uint32_t keys;
-
- union {
- struct bkey start[0];
- uint64_t d[0];
- };
-};
-
-/*
- * On disk format for priorities and gens - see super.c near prio_write() for
- * more.
- */
-struct prio_set {
- uint64_t csum;
- uint64_t magic;
- uint64_t seq;
- uint32_t version;
- uint32_t pad;
-
- uint64_t next_bucket;
-
- struct bucket_disk {
- uint16_t prio;
- uint8_t gen;
- } __attribute((packed)) data[];
-};
-
-struct uuid_entry {
- union {
- struct {
- uint8_t uuid[16];
- uint8_t label[32];
- uint32_t first_reg;
- uint32_t last_reg;
- uint32_t invalidated;
-
- uint32_t flags;
- /* Size of flash only volumes */
- uint64_t sectors;
- };
-
- uint8_t pad[128];
- };
-};
-
-BITMASK(UUID_FLASH_ONLY, struct uuid_entry, flags, 0, 1);
-
#include "journal.h"
#include "stats.h"
struct search;
@@ -868,12 +707,6 @@ static inline bool key_merging_disabled(struct cache_set *c)
#endif
}
-static inline bool SB_IS_BDEV(const struct cache_sb *sb)
-{
- return sb->version == BCACHE_SB_VERSION_BDEV
- || sb->version == BCACHE_SB_VERSION_BDEV_WITH_OFFSET;
-}
-
struct bbio {
unsigned submit_time_us;
union {
@@ -927,59 +760,6 @@ static inline unsigned local_clock_us(void)
#define prio_buckets(c) \
DIV_ROUND_UP((size_t) (c)->sb.nbuckets, prios_per_bucket(c))
-#define JSET_MAGIC 0x245235c1a3625032ULL
-#define PSET_MAGIC 0x6750e15f87337f91ULL
-#define BSET_MAGIC 0x90135c78b99e07f5ULL
-
-#define jset_magic(c) ((c)->sb.set_magic ^ JSET_MAGIC)
-#define pset_magic(c) ((c)->sb.set_magic ^ PSET_MAGIC)
-#define bset_magic(c) ((c)->sb.set_magic ^ BSET_MAGIC)
-
-/* Bkey fields: all units are in sectors */
-
-#define KEY_FIELD(name, field, offset, size) \
- BITMASK(name, struct bkey, field, offset, size)
-
-#define PTR_FIELD(name, offset, size) \
- static inline uint64_t name(const struct bkey *k, unsigned i) \
- { return (k->ptr[i] >> offset) & ~(((uint64_t) ~0) << size); } \
- \
- static inline void SET_##name(struct bkey *k, unsigned i, uint64_t v)\
- { \
- k->ptr[i] &= ~(~((uint64_t) ~0 << size) << offset); \
- k->ptr[i] |= v << offset; \
- }
-
-KEY_FIELD(KEY_PTRS, high, 60, 3)
-KEY_FIELD(HEADER_SIZE, high, 58, 2)
-KEY_FIELD(KEY_CSUM, high, 56, 2)
-KEY_FIELD(KEY_PINNED, high, 55, 1)
-KEY_FIELD(KEY_DIRTY, high, 36, 1)
-
-KEY_FIELD(KEY_SIZE, high, 20, 16)
-KEY_FIELD(KEY_INODE, high, 0, 20)
-
-/* Next time I change the on disk format, KEY_OFFSET() won't be 64 bits */
-
-static inline uint64_t KEY_OFFSET(const struct bkey *k)
-{
- return k->low;
-}
-
-static inline void SET_KEY_OFFSET(struct bkey *k, uint64_t v)
-{
- k->low = v;
-}
-
-PTR_FIELD(PTR_DEV, 51, 12)
-PTR_FIELD(PTR_OFFSET, 8, 43)
-PTR_FIELD(PTR_GEN, 0, 8)
-
-#define PTR_CHECK_DEV ((1 << 12) - 1)
-
-#define PTR(gen, offset, dev) \
- ((((uint64_t) dev) << 51) | ((uint64_t) offset) << 8 | gen)
-
static inline size_t sector_to_bucket(struct cache_set *c, sector_t s)
{
return s >> c->bucket_bits;
@@ -1018,31 +798,11 @@ static inline struct bucket *PTR_BUCKET(struct cache_set *c,
/* Btree key macros */
-/*
- * The high bit being set is a relic from when we used it to do binary
- * searches - it told you where a key started. It's not used anymore,
- * and can probably be safely dropped.
- */
-#define KEY(dev, sector, len) \
-((struct bkey) { \
- .high = (1ULL << 63) | ((uint64_t) (len) << 20) | (dev), \
- .low = (sector) \
-})
-
static inline void bkey_init(struct bkey *k)
{
- *k = KEY(0, 0, 0);
+ *k = ZERO_KEY;
}
-#define KEY_START(k) (KEY_OFFSET(k) - KEY_SIZE(k))
-#define START_KEY(k) KEY(KEY_INODE(k), KEY_START(k), 0)
-
-#define MAX_KEY_INODE (~(~0 << 20))
-#define MAX_KEY_OFFSET (((uint64_t) ~0) >> 1)
-#define MAX_KEY KEY(MAX_KEY_INODE, MAX_KEY_OFFSET, 0)
-
-#define ZERO_KEY KEY(0, 0, 0)
-
/*
* This is used for various on disk data structures - cache_sb, prio_set, bset,
* jset: The checksum is _always_ the first 8 bytes of these structs
diff --git a/drivers/md/bcache/bset.c b/drivers/md/bcache/bset.c
index f7b5525ddafa..7b8713c66050 100644
--- a/drivers/md/bcache/bset.c
+++ b/drivers/md/bcache/bset.c
@@ -684,7 +684,7 @@ void bch_bset_init_next(struct btree *b)
} else
get_random_bytes(&i->seq, sizeof(uint64_t));
- i->magic = bset_magic(b->c);
+ i->magic = bset_magic(&b->c->sb);
i->version = 0;
i->keys = 0;
@@ -1034,7 +1034,7 @@ static void __btree_sort(struct btree *b, struct btree_iter *iter,
* memcpy()
*/
- out->magic = bset_magic(b->c);
+ out->magic = bset_magic(&b->c->sb);
out->seq = b->sets[0].data->seq;
out->version = b->sets[0].data->version;
swap(out, b->sets[0].data);
diff --git a/drivers/md/bcache/bset.h b/drivers/md/bcache/bset.h
index 8a9305685b7e..5cd90565dfe2 100644
--- a/drivers/md/bcache/bset.h
+++ b/drivers/md/bcache/bset.h
@@ -193,37 +193,6 @@ static __always_inline int64_t bkey_cmp(const struct bkey *l,
: (int64_t) KEY_OFFSET(l) - (int64_t) KEY_OFFSET(r);
}
-static inline size_t bkey_u64s(const struct bkey *k)
-{
- BUG_ON(KEY_CSUM(k) > 1);
- return 2 + KEY_PTRS(k) + (KEY_CSUM(k) ? 1 : 0);
-}
-
-static inline size_t bkey_bytes(const struct bkey *k)
-{
- return bkey_u64s(k) * sizeof(uint64_t);
-}
-
-static inline void bkey_copy(struct bkey *dest, const struct bkey *src)
-{
- memcpy(dest, src, bkey_bytes(src));
-}
-
-static inline void bkey_copy_key(struct bkey *dest, const struct bkey *src)
-{
- if (!src)
- src = &KEY(0, 0, 0);
-
- SET_KEY_INODE(dest, KEY_INODE(src));
- SET_KEY_OFFSET(dest, KEY_OFFSET(src));
-}
-
-static inline struct bkey *bkey_next(const struct bkey *k)
-{
- uint64_t *d = (void *) k;
- return (struct bkey *) (d + bkey_u64s(k));
-}
-
/* Keylists */
struct keylist {
diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index f5aa4adadf1d..aba787d954e5 100644
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -231,7 +231,7 @@ static void bch_btree_node_read_done(struct btree *b)
goto err;
err = "bad magic";
- if (i->magic != bset_magic(b->c))
+ if (i->magic != bset_magic(&b->c->sb))
goto err;
err = "bad checksum";
diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c
index 86de64a6bf26..ecdaa671bd50 100644
--- a/drivers/md/bcache/journal.c
+++ b/drivers/md/bcache/journal.c
@@ -74,7 +74,7 @@ reread: left = ca->sb.bucket_size - offset;
struct list_head *where;
size_t blocks, bytes = set_bytes(j);
- if (j->magic != jset_magic(ca->set))
+ if (j->magic != jset_magic(&ca->sb))
return ret;
if (bytes > left << 9)
@@ -596,7 +596,7 @@ static void journal_write_unlocked(struct closure *cl)
for_each_cache(ca, c, i)
w->data->prio_bucket[ca->sb.nr_this_dev] = ca->prio_buckets[0];
- w->data->magic = jset_magic(c);
+ w->data->magic = jset_magic(&c->sb);
w->data->version = BCACHE_JSET_VERSION;
w->data->last_seq = last_seq(&c->journal);
w->data->csum = csum_set(w->data);
diff --git a/drivers/md/bcache/journal.h b/drivers/md/bcache/journal.h
index 5e9edb9ef376..a6472fda94b2 100644
--- a/drivers/md/bcache/journal.h
+++ b/drivers/md/bcache/journal.h
@@ -75,43 +75,6 @@
* nodes that are pinning the oldest journal entries first.
*/
-#define BCACHE_JSET_VERSION_UUIDv1 1
-/* Always latest UUID format */
-#define BCACHE_JSET_VERSION_UUID 1
-#define BCACHE_JSET_VERSION 1
-
-/*
- * On disk format for a journal entry:
- * seq is monotonically increasing; every journal entry has its own unique
- * sequence number.
- *
- * last_seq is the oldest journal entry that still has keys the btree hasn't
- * flushed to disk yet.
- *
- * version is for on disk format changes.
- */
-struct jset {
- uint64_t csum;
- uint64_t magic;
- uint64_t seq;
- uint32_t version;
- uint32_t keys;
-
- uint64_t last_seq;
-
- BKEY_PADDED(uuid_bucket);
- BKEY_PADDED(btree_root);
- uint16_t btree_level;
- uint16_t pad[3];
-
- uint64_t prio_bucket[MAX_CACHES_PER_SET];
-
- union {
- struct bkey start[0];
- uint64_t d[0];
- };
-};
-
/*
* Only used for holding the journal entries we read in btree_journal_read()
* during cache_registration
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index cf7850a7592c..932300f18973 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -264,16 +264,17 @@ static void bch_data_invalidate(struct closure *cl)
bio_sectors(bio), (uint64_t) bio->bi_sector);
while (bio_sectors(bio)) {
- unsigned len = min(bio_sectors(bio), 1U << 14);
+ unsigned sectors = min(bio_sectors(bio),
+ 1U << (KEY_SIZE_BITS - 1));
if (bch_keylist_realloc(&op->insert_keys, 0, op->c))
goto out;
- bio->bi_sector += len;
- bio->bi_size -= len << 9;
+ bio->bi_sector += sectors;
+ bio->bi_size -= sectors << 9;
bch_keylist_add(&op->insert_keys,
- &KEY(op->inode, bio->bi_sector, len));
+ &KEY(op->inode, bio->bi_sector, sectors));
}
op->insert_data_done = true;
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index a314c771263f..c67d19a8913d 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -45,15 +45,6 @@ const char * const bch_cache_modes[] = {
NULL
};
-struct uuid_entry_v0 {
- uint8_t uuid[16];
- uint8_t label[32];
- uint32_t first_reg;
- uint32_t last_reg;
- uint32_t invalidated;
- uint32_t pad;
-};
-
static struct kobject *bcache_kobj;
struct mutex bch_register_lock;
LIST_HEAD(bch_cache_sets);
@@ -562,7 +553,7 @@ void bch_prio_write(struct cache *ca)
}
p->next_bucket = ca->prio_buckets[i + 1];
- p->magic = pset_magic(ca);
+ p->magic = pset_magic(&ca->sb);
p->csum = bch_crc64(&p->magic, bucket_bytes(ca) - 8);
bucket = bch_bucket_alloc(ca, WATERMARK_PRIO, true);
@@ -613,7 +604,7 @@ static void prio_read(struct cache *ca, uint64_t bucket)
if (p->csum != bch_crc64(&p->magic, bucket_bytes(ca) - 8))
pr_warn("bad csum reading priorities");
- if (p->magic != pset_magic(ca))
+ if (p->magic != pset_magic(&ca->sb))
pr_warn("bad magic reading priorities");
bucket = p->next_bucket;
diff --git a/drivers/md/bcache/util.h b/drivers/md/bcache/util.h
index ea345c6896f4..38ae7a4ce928 100644
--- a/drivers/md/bcache/util.h
+++ b/drivers/md/bcache/util.h
@@ -27,16 +27,6 @@ struct closure;
#endif
-#define BITMASK(name, type, field, offset, size) \
-static inline uint64_t name(const type *k) \
-{ return (k->field >> offset) & ~(((uint64_t) ~0) << size); } \
- \
-static inline void SET_##name(type *k, uint64_t v) \
-{ \
- k->field &= ~(~((uint64_t) ~0 << size) << offset); \
- k->field |= v << offset; \
-}
-
#define DECLARE_HEAP(type, name) \
struct { \
size_t size, used; \
diff --git a/include/uapi/linux/bcache.h b/include/uapi/linux/bcache.h
new file mode 100644
index 000000000000..164a7e263988
--- /dev/null
+++ b/include/uapi/linux/bcache.h
@@ -0,0 +1,373 @@
+#ifndef _LINUX_BCACHE_H
+#define _LINUX_BCACHE_H
+
+/*
+ * Bcache on disk data structures
+ */
+
+#include <asm/types.h>
+
+#define BITMASK(name, type, field, offset, size) \
+static inline __u64 name(const type *k) \
+{ return (k->field >> offset) & ~(~0ULL << size); } \
+ \
+static inline void SET_##name(type *k, __u64 v) \
+{ \
+ k->field &= ~(~(~0ULL << size) << offset); \
+ k->field |= (v & ~(~0ULL << size)) << offset; \
+}
+
+/* Btree keys - all units are in sectors */
+
+struct bkey {
+ __u64 high;
+ __u64 low;
+ __u64 ptr[];
+};
+
+#define KEY_FIELD(name, field, offset, size) \
+ BITMASK(name, struct bkey, field, offset, size)
+
+#define PTR_FIELD(name, offset, size) \
+static inline __u64 name(const struct bkey *k, unsigned i) \
+{ return (k->ptr[i] >> offset) & ~(~0ULL << size); } \
+ \
+static inline void SET_##name(struct bkey *k, unsigned i, __u64 v) \
+{ \
+ k->ptr[i] &= ~(~(~0ULL << size) << offset); \
+ k->ptr[i] |= (v & ~(~0ULL << size)) << offset; \
+}
+
+#define KEY_SIZE_BITS 16
+
+KEY_FIELD(KEY_PTRS, high, 60, 3)
+KEY_FIELD(HEADER_SIZE, high, 58, 2)
+KEY_FIELD(KEY_CSUM, high, 56, 2)
+KEY_FIELD(KEY_PINNED, high, 55, 1)
+KEY_FIELD(KEY_DIRTY, high, 36, 1)
+
+KEY_FIELD(KEY_SIZE, high, 20, KEY_SIZE_BITS)
+KEY_FIELD(KEY_INODE, high, 0, 20)
+
+/* Next time I change the on disk format, KEY_OFFSET() won't be 64 bits */
+
+static inline __u64 KEY_OFFSET(const struct bkey *k)
+{
+ return k->low;
+}
+
+static inline void SET_KEY_OFFSET(struct bkey *k, __u64 v)
+{
+ k->low = v;
+}
+
+/*
+ * The high bit being set is a relic from when we used it to do binary
+ * searches - it told you where a key started. It's not used anymore,
+ * and can probably be safely dropped.
+ */
+#define KEY(inode, offset, size) \
+((struct bkey) { \
+ .high = (1ULL << 63) | ((__u64) (size) << 20) | (inode), \
+ .low = (offset) \
+})
+
+#define ZERO_KEY KEY(0, 0, 0)
+
+#define MAX_KEY_INODE (~(~0 << 20))
+#define MAX_KEY_OFFSET (~0ULL >> 1)
+#define MAX_KEY KEY(MAX_KEY_INODE, MAX_KEY_OFFSET, 0)
+
+#define KEY_START(k) (KEY_OFFSET(k) - KEY_SIZE(k))
+#define START_KEY(k) KEY(KEY_INODE(k), KEY_START(k), 0)
+
+#define PTR_DEV_BITS 12
+
+PTR_FIELD(PTR_DEV, 51, PTR_DEV_BITS)
+PTR_FIELD(PTR_OFFSET, 8, 43)
+PTR_FIELD(PTR_GEN, 0, 8)
+
+#define PTR_CHECK_DEV ((1 << PTR_DEV_BITS) - 1)
+
+#define PTR(gen, offset, dev) \
+ ((((__u64) dev) << 51) | ((__u64) offset) << 8 | gen)
+
+/* Bkey utility code */
+
+static inline unsigned long bkey_u64s(const struct bkey *k)
+{
+ return (sizeof(struct bkey) / sizeof(__u64)) + KEY_PTRS(k);
+}
+
+static inline unsigned long bkey_bytes(const struct bkey *k)
+{
+ return bkey_u64s(k) * sizeof(__u64);
+}
+
+#define bkey_copy(_dest, _src) memcpy(_dest, _src, bkey_bytes(_src))
+
+static inline void bkey_copy_key(struct bkey *dest, const struct bkey *src)
+{
+ SET_KEY_INODE(dest, KEY_INODE(src));
+ SET_KEY_OFFSET(dest, KEY_OFFSET(src));
+}
+
+static inline struct bkey *bkey_next(const struct bkey *k)
+{
+ __u64 *d = (void *) k;
+ return (struct bkey *) (d + bkey_u64s(k));
+}
+
+static inline struct bkey *bkey_last(const struct bkey *k, unsigned nr_keys)
+{
+ __u64 *d = (void *) k;
+ return (struct bkey *) (d + nr_keys);
+}
+/* Enough for a key with 6 pointers */
+#define BKEY_PAD 8
+
+#define BKEY_PADDED(key) \
+ union { struct bkey key; __u64 key ## _pad[BKEY_PAD]; }
+
+/* Superblock */
+
+/* Version 0: Cache device
+ * Version 1: Backing device
+ * Version 2: Seed pointer into btree node checksum
+ * Version 3: Cache device with new UUID format
+ * Version 4: Backing device with data offset
+ */
+#define BCACHE_SB_VERSION_CDEV 0
+#define BCACHE_SB_VERSION_BDEV 1
+#define BCACHE_SB_VERSION_CDEV_WITH_UUID 3
+#define BCACHE_SB_VERSION_BDEV_WITH_OFFSET 4
+#define BCACHE_SB_MAX_VERSION 4
+
+#define SB_SECTOR 8
+#define SB_SIZE 4096
+#define SB_LABEL_SIZE 32
+#define SB_JOURNAL_BUCKETS 256U
+/* SB_JOURNAL_BUCKETS must be divisible by BITS_PER_LONG */
+#define MAX_CACHES_PER_SET 8
+
+#define BDEV_DATA_START_DEFAULT 16 /* sectors */
+
+struct cache_sb {
+ __u64 csum;
+ __u64 offset; /* sector where this sb was written */
+ __u64 version;
+
+ __u8 magic[16];
+
+ __u8 uuid[16];
+ union {
+ __u8 set_uuid[16];
+ __u64 set_magic;
+ };
+ __u8 label[SB_LABEL_SIZE];
+
+ __u64 flags;
+ __u64 seq;
+ __u64 pad[8];
+
+ union {
+ struct {
+ /* Cache devices */
+ __u64 nbuckets; /* device size */
+
+ __u16 block_size; /* sectors */
+ __u16 bucket_size; /* sectors */
+
+ __u16 nr_in_set;
+ __u16 nr_this_dev;
+ };
+ struct {
+ /* Backing devices */
+ __u64 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
+ */
+ };
+ };
+
+ __u32 last_mount; /* time_t */
+
+ __u16 first_bucket;
+ union {
+ __u16 njournal_buckets;
+ __u16 keys;
+ };
+ __u64 d[SB_JOURNAL_BUCKETS]; /* journal buckets */
+};
+
+static inline _Bool SB_IS_BDEV(const struct cache_sb *sb)
+{
+ return sb->version == BCACHE_SB_VERSION_BDEV
+ || sb->version == BCACHE_SB_VERSION_BDEV_WITH_OFFSET;
+}
+
+BITMASK(CACHE_SYNC, struct cache_sb, flags, 0, 1);
+BITMASK(CACHE_DISCARD, struct cache_sb, flags, 1, 1);
+BITMASK(CACHE_REPLACEMENT, struct cache_sb, flags, 2, 3);
+#define CACHE_REPLACEMENT_LRU 0U
+#define CACHE_REPLACEMENT_FIFO 1U
+#define CACHE_REPLACEMENT_RANDOM 2U
+
+BITMASK(BDEV_CACHE_MODE, struct cache_sb, flags, 0, 4);
+#define CACHE_MODE_WRITETHROUGH 0U
+#define CACHE_MODE_WRITEBACK 1U
+#define CACHE_MODE_WRITEAROUND 2U
+#define CACHE_MODE_NONE 3U
+BITMASK(BDEV_STATE, struct cache_sb, flags, 61, 2);
+#define BDEV_STATE_NONE 0U
+#define BDEV_STATE_CLEAN 1U
+#define BDEV_STATE_DIRTY 2U
+#define BDEV_STATE_STALE 3U
+
+/*
+ * Magic numbers
+ *
+ * The various other data structures have their own magic numbers, which are
+ * xored with the first part of the cache set's UUID
+ */
+
+#define JSET_MAGIC 0x245235c1a3625032ULL
+#define PSET_MAGIC 0x6750e15f87337f91ULL
+#define BSET_MAGIC 0x90135c78b99e07f5ULL
+
+static inline __u64 jset_magic(struct cache_sb *sb)
+{
+ return sb->set_magic ^ JSET_MAGIC;
+}
+
+static inline __u64 pset_magic(struct cache_sb *sb)
+{
+ return sb->set_magic ^ PSET_MAGIC;
+}
+
+static inline __u64 bset_magic(struct cache_sb *sb)
+{
+ return sb->set_magic ^ BSET_MAGIC;
+}
+
+/*
+ * Journal
+ *
+ * On disk format for a journal entry:
+ * seq is monotonically increasing; every journal entry has its own unique
+ * sequence number.
+ *
+ * last_seq is the oldest journal entry that still has keys the btree hasn't
+ * flushed to disk yet.
+ *
+ * version is for on disk format changes.
+ */
+
+#define BCACHE_JSET_VERSION_UUIDv1 1
+#define BCACHE_JSET_VERSION_UUID 1 /* Always latest UUID format */
+#define BCACHE_JSET_VERSION 1
+
+struct jset {
+ __u64 csum;
+ __u64 magic;
+ __u64 seq;
+ __u32 version;
+ __u32 keys;
+
+ __u64 last_seq;
+
+ BKEY_PADDED(uuid_bucket);
+ BKEY_PADDED(btree_root);
+ __u16 btree_level;
+ __u16 pad[3];
+
+ __u64 prio_bucket[MAX_CACHES_PER_SET];
+
+ union {
+ struct bkey start[0];
+ __u64 d[0];
+ };
+};
+
+/* Bucket prios/gens */
+
+struct prio_set {
+ __u64 csum;
+ __u64 magic;
+ __u64 seq;
+ __u32 version;
+ __u32 pad;
+
+ __u64 next_bucket;
+
+ struct bucket_disk {
+ __u16 prio;
+ __u8 gen;
+ } __attribute((packed)) data[];
+};
+
+/* UUIDS - per backing device/flash only volume metadata */
+
+struct uuid_entry {
+ union {
+ struct {
+ __u8 uuid[16];
+ __u8 label[32];
+ __u32 first_reg;
+ __u32 last_reg;
+ __u32 invalidated;
+
+ __u32 flags;
+ /* Size of flash only volumes */
+ __u64 sectors;
+ };
+
+ __u8 pad[128];
+ };
+};
+
+BITMASK(UUID_FLASH_ONLY, struct uuid_entry, flags, 0, 1);
+
+/* Btree nodes */
+
+/* Version 1: Seed pointer into btree node checksum
+ */
+#define BCACHE_BSET_CSUM 1
+#define BCACHE_BSET_VERSION 1
+
+/*
+ * Btree nodes
+ *
+ * On disk a btree node is a list/log of these; within each set the keys are
+ * sorted
+ */
+struct bset {
+ __u64 csum;
+ __u64 magic;
+ __u64 seq;
+ __u32 version;
+ __u32 keys;
+
+ union {
+ struct bkey start[0];
+ __u64 d[0];
+ };
+};
+
+/* OBSOLETE */
+
+/* UUIDS - per backing device/flash only volume metadata */
+
+struct uuid_entry_v0 {
+ __u8 uuid[16];
+ __u8 label[32];
+ __u32 first_reg;
+ __u32 last_reg;
+ __u32 invalidated;
+ __u32 pad;
+};
+
+#endif /* _LINUX_BCACHE_H */
generated by cgit (git 2.34.1) at 2025-11-04 06:21:18 +0000