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>

1 files changed, 197 insertions, 0 deletions

diff --git a/fs/bcachefs/btree_io.h b/fs/bcachefs/btree_io.h
new file mode 100644
index 000000000000..0688ce420610
--- /dev/null
+++ b/fs/bcachefs/btree_io.h
@@ -0,0 +1,197 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _BCACHEFS_BTREE_IO_H
+#define _BCACHEFS_BTREE_IO_H
+
+#include "bset.h"
+#include "extents.h"
+#include "io_types.h"
+
+struct bch_fs;
+struct btree_write;
+struct btree;
+struct btree_iter;
+
+struct btree_read_bio {
+	struct bch_fs		*c;
+	u64			start_time;
+	unsigned		have_ioref:1;
+	struct extent_pick_ptr	pick;
+	struct work_struct	work;
+	struct bio		bio;
+};
+
+struct btree_write_bio {
+	void			*data;
+	struct work_struct	work;
+	struct bch_write_bio	wbio;
+};
+
+static inline void btree_node_io_unlock(struct btree *b)
+{
+	EBUG_ON(!btree_node_write_in_flight(b));
+	clear_btree_node_write_in_flight(b);
+	wake_up_bit(&b->flags, BTREE_NODE_write_in_flight);
+}
+
+static inline void btree_node_io_lock(struct btree *b)
+{
+	wait_on_bit_lock_io(&b->flags, BTREE_NODE_write_in_flight,
+			    TASK_UNINTERRUPTIBLE);
+}
+
+static inline void btree_node_wait_on_io(struct btree *b)
+{
+	wait_on_bit_io(&b->flags, BTREE_NODE_write_in_flight,
+		       TASK_UNINTERRUPTIBLE);
+}
+
+static inline bool btree_node_may_write(struct btree *b)
+{
+	return list_empty_careful(&b->write_blocked) &&
+		!b->will_make_reachable;
+}
+
+enum compact_mode {
+	COMPACT_LAZY,
+	COMPACT_WRITTEN,
+	COMPACT_WRITTEN_NO_WRITE_LOCK,
+};
+
+bool __bch2_compact_whiteouts(struct bch_fs *, struct btree *, enum compact_mode);
+
+static inline unsigned should_compact_bset_lazy(struct btree *b, struct bset_tree *t)
+{
+	unsigned bset_u64s = le16_to_cpu(bset(b, t)->u64s);
+	unsigned dead_u64s = bset_u64s - b->nr.bset_u64s[t - b->set];
+
+	return dead_u64s > 128 && dead_u64s * 3 > bset_u64s;
+}
+
+static inline bool bch2_maybe_compact_whiteouts(struct bch_fs *c, struct btree *b)
+{
+	struct bset_tree *t;
+
+	for_each_bset(b, t)
+		if (should_compact_bset_lazy(b, t))
+			return __bch2_compact_whiteouts(c, b, COMPACT_LAZY);
+
+	return false;
+}
+
+void bch2_btree_sort_into(struct bch_fs *, struct btree *, struct btree *);
+
+void bch2_btree_build_aux_trees(struct btree *);
+void bch2_btree_init_next(struct bch_fs *, struct btree *,
+			 struct btree_iter *);
+
+int bch2_btree_node_read_done(struct bch_fs *, struct btree *, bool);
+void bch2_btree_node_read(struct bch_fs *, struct btree *, bool);
+int bch2_btree_root_read(struct bch_fs *, enum btree_id,
+			 const struct bkey_i *, unsigned);
+
+void bch2_btree_complete_write(struct bch_fs *, struct btree *,
+			      struct btree_write *);
+void bch2_btree_write_error_work(struct work_struct *);
+
+void __bch2_btree_node_write(struct bch_fs *, struct btree *,
+			    enum six_lock_type);
+bool bch2_btree_post_write_cleanup(struct bch_fs *, struct btree *);
+
+void bch2_btree_node_write(struct bch_fs *, struct btree *,
+			  enum six_lock_type);
+
+/*
+ * btree_node_dirty() can be cleared with only a read lock,
+ * and for bch2_btree_node_write_cond() we want to set need_write iff it's
+ * still dirty:
+ */
+static inline void set_btree_node_need_write_if_dirty(struct btree *b)
+{
+	unsigned long old, new, v = READ_ONCE(b->flags);
+
+	do {
+		old = new = v;
+
+		if (!(old & (1 << BTREE_NODE_dirty)))
+			return;
+
+		new |= (1 << BTREE_NODE_need_write);
+	} while ((v = cmpxchg(&b->flags, old, new)) != old);
+}
+
+#define bch2_btree_node_write_cond(_c, _b, cond)			\
+do {									\
+	while ((_b)->written && btree_node_dirty(_b) &&	(cond)) {	\
+		if (!btree_node_may_write(_b)) {			\
+			set_btree_node_need_write_if_dirty(_b);		\
+			break;						\
+		}							\
+									\
+		if (!btree_node_write_in_flight(_b)) {			\
+			bch2_btree_node_write(_c, _b, SIX_LOCK_read);	\
+			break;						\
+		}							\
+									\
+		six_unlock_read(&(_b)->lock);				\
+		btree_node_wait_on_io(_b);				\
+		btree_node_lock_type(c, b, SIX_LOCK_read);		\
+	}								\
+} while (0)
+
+void bch2_btree_flush_all_reads(struct bch_fs *);
+void bch2_btree_flush_all_writes(struct bch_fs *);
+void bch2_btree_verify_flushed(struct bch_fs *);
+ssize_t bch2_dirty_btree_nodes_print(struct bch_fs *, char *);
+
+/* Sorting */
+
+struct btree_node_iter_large {
+	u8		is_extents;
+	u16		used;
+
+	struct btree_node_iter_set data[MAX_BSETS];
+};
+
+static inline void
+__bch2_btree_node_iter_large_init(struct btree_node_iter_large *iter,
+				  bool is_extents)
+{
+	iter->used = 0;
+	iter->is_extents = is_extents;
+}
+
+void bch2_btree_node_iter_large_advance(struct btree_node_iter_large *,
+					struct btree *);
+
+void bch2_btree_node_iter_large_push(struct btree_node_iter_large *,
+				     struct btree *,
+				     const struct bkey_packed *,
+				     const struct bkey_packed *);
+
+static inline bool bch2_btree_node_iter_large_end(struct btree_node_iter_large *iter)
+{
+	return !iter->used;
+}
+
+static inline struct bkey_packed *
+bch2_btree_node_iter_large_peek_all(struct btree_node_iter_large *iter,
+				    struct btree *b)
+{
+	return bch2_btree_node_iter_large_end(iter)
+		? NULL
+		: __btree_node_offset_to_key(b, iter->data->k);
+}
+
+static inline struct bkey_packed *
+bch2_btree_node_iter_large_next_all(struct btree_node_iter_large *iter,
+				    struct btree *b)
+{
+	struct bkey_packed *ret = bch2_btree_node_iter_large_peek_all(iter, b);
+
+	if (ret)
+		bch2_btree_node_iter_large_advance(iter, b);
+
+	return ret;
+}
+
+#endif /* _BCACHEFS_BTREE_IO_H */