bcachefs: Initial commit
Initially forked from drivers/md/bcache, bcachefs is a new copy-on-write
filesystem with every feature you could possibly want.
Website: https://bcachefs.org
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
diff --git a/fs/bcachefs/alloc_types.h b/fs/bcachefs/alloc_types.h
new file mode 100644
index 0000000..035c5005
--- /dev/null
+++ b/fs/bcachefs/alloc_types.h
@@ -0,0 +1,90 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _BCACHEFS_ALLOC_TYPES_H
+#define _BCACHEFS_ALLOC_TYPES_H
+
+#include <linux/mutex.h>
+#include <linux/spinlock.h>
+
+#include "clock_types.h"
+#include "fifo.h"
+
+/* There's two of these clocks, one for reads and one for writes: */
+struct bucket_clock {
+ /*
+ * "now" in (read/write) IO time - incremented whenever we do X amount
+ * of reads or writes.
+ *
+ * Goes with the bucket read/write prios: when we read or write to a
+ * bucket we reset the bucket's prio to the current hand; thus hand -
+ * prio = time since bucket was last read/written.
+ *
+ * The units are some amount (bytes/sectors) of data read/written, and
+ * the units can change on the fly if we need to rescale to fit
+ * everything in a u16 - your only guarantee is that the units are
+ * consistent.
+ */
+ u16 hand;
+ u16 max_last_io;
+
+ int rw;
+
+ struct io_timer rescale;
+ struct mutex lock;
+};
+
+/* There is one reserve for each type of btree, one for prios and gens
+ * and one for moving GC */
+enum alloc_reserve {
+ RESERVE_ALLOC = -1,
+ RESERVE_BTREE = 0,
+ RESERVE_MOVINGGC = 1,
+ RESERVE_NONE = 2,
+ RESERVE_NR = 3,
+};
+
+typedef FIFO(long) alloc_fifo;
+
+/* Enough for 16 cache devices, 2 tiers and some left over for pipelining */
+#define OPEN_BUCKETS_COUNT 256
+#define WRITE_POINT_COUNT 32
+
+struct open_bucket {
+ spinlock_t lock;
+ atomic_t pin;
+ u8 freelist;
+ bool valid;
+ bool on_partial_list;
+ unsigned sectors_free;
+ struct bch_extent_ptr ptr;
+};
+
+struct write_point {
+ struct hlist_node node;
+ struct mutex lock;
+ u64 last_used;
+ unsigned long write_point;
+ enum bch_data_type type;
+
+ u8 nr_ptrs;
+ u8 first_ptr;
+
+ /* calculated based on how many pointers we're actually going to use: */
+ unsigned sectors_free;
+
+ struct open_bucket *ptrs[BCH_REPLICAS_MAX * 2];
+ u64 next_alloc[BCH_SB_MEMBERS_MAX];
+};
+
+struct write_point_specifier {
+ unsigned long v;
+};
+
+struct alloc_heap_entry {
+ size_t bucket;
+ size_t nr;
+ unsigned long key;
+};
+
+typedef HEAP(struct alloc_heap_entry) alloc_heap;
+
+#endif /* _BCACHEFS_ALLOC_TYPES_H */
