From edaed8ee8cb3fdb6b9fcde65ff31e99e4db59cab Mon Sep 17 00:00:00 2001
From: Kent Overstreet <kent.overstreet@linux.dev>
Date: Sun, 30 Mar 2025 16:50:59 -0400
Subject: [PATCH] bcachefs: BCH_JSET_ENTRY_log_bkey

Add a journal entry type for logging - but logging a bkey, not a string;
to be used for data move path debugging.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
---
 fs/bcachefs/bcachefs_format.h |  3 ++-
 fs/bcachefs/btree_update.c    | 13 +++++++++++++
 fs/bcachefs/btree_update.h    |  2 ++
 fs/bcachefs/journal_io.c      | 17 +++++++++++++++++
 4 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/fs/bcachefs/bcachefs_format.h b/fs/bcachefs/bcachefs_format.h
index e96d87767020..a3db328dee31 100644
--- a/fs/bcachefs/bcachefs_format.h
+++ b/fs/bcachefs/bcachefs_format.h
@@ -1143,7 +1143,8 @@ static inline __u64 __bset_magic(struct bch_sb *sb)
 	x(log,			9)		\
 	x(overwrite,		10)		\
 	x(write_buffer_keys,	11)		\
-	x(datetime,		12)
+	x(datetime,		12)		\
+	x(log_bkey,		13)
 
 enum bch_jset_entry_type {
 #define x(f, nr)	BCH_JSET_ENTRY_##f	= nr,
diff --git a/fs/bcachefs/btree_update.c b/fs/bcachefs/btree_update.c
index bd2eb42edb24..c05394f56424 100644
--- a/fs/bcachefs/btree_update.c
+++ b/fs/bcachefs/btree_update.c
@@ -846,6 +846,19 @@ int bch2_trans_log_msg(struct btree_trans *trans, struct printbuf *buf)
 	return 0;
 }
 
+int bch2_trans_log_bkey(struct btree_trans *trans, enum btree_id btree,
+			unsigned level, struct bkey_i *k)
+{
+	struct jset_entry *e = bch2_trans_jset_entry_alloc(trans, jset_u64s(k->k.u64s));
+	int ret = PTR_ERR_OR_ZERO(e);
+	if (ret)
+		return ret;
+
+	journal_entry_init(e, BCH_JSET_ENTRY_log_bkey, btree, level, k->k.u64s);
+	bkey_copy(e->start, k);
+	return 0;
+}
+
 __printf(3, 0)
 static int
 __bch2_fs_log_msg(struct bch_fs *c, unsigned commit_flags, const char *fmt,
diff --git a/fs/bcachefs/btree_update.h b/fs/bcachefs/btree_update.h
index d2e1c04353f6..568e56c91190 100644
--- a/fs/bcachefs/btree_update.h
+++ b/fs/bcachefs/btree_update.h
@@ -170,6 +170,8 @@ void bch2_trans_commit_hook(struct btree_trans *,
 int __bch2_trans_commit(struct btree_trans *, unsigned);
 
 int bch2_trans_log_msg(struct btree_trans *, struct printbuf *);
+int bch2_trans_log_bkey(struct btree_trans *, enum btree_id, unsigned, struct bkey_i *);
+
 __printf(2, 3) int bch2_fs_log_msg(struct bch_fs *, const char *, ...);
 __printf(2, 3) int bch2_journal_log_msg(struct bch_fs *, const char *, ...);
 
diff --git a/fs/bcachefs/journal_io.c b/fs/bcachefs/journal_io.c
index 228e531921b7..2debc213e47c 100644
--- a/fs/bcachefs/journal_io.c
+++ b/fs/bcachefs/journal_io.c
@@ -764,6 +764,23 @@ static void journal_entry_overwrite_to_text(struct printbuf *out, struct bch_fs
 	journal_entry_btree_keys_to_text(out, c, entry);
 }
 
+static int journal_entry_log_bkey_validate(struct bch_fs *c,
+				struct jset *jset,
+				struct jset_entry *entry,
+				unsigned version, int big_endian,
+				struct bkey_validate_context from)
+{
+	from.flags = 0;
+	return journal_entry_btree_keys_validate(c, jset, entry,
+				version, big_endian, from);
+}
+
+static void journal_entry_log_bkey_to_text(struct printbuf *out, struct bch_fs *c,
+					   struct jset_entry *entry)
+{
+	journal_entry_btree_keys_to_text(out, c, entry);
+}
+
 static int journal_entry_write_buffer_keys_validate(struct bch_fs *c,
 				struct jset *jset,
 				struct jset_entry *entry,