bcachefs: bch2_require_recovery_pass()

Add a helper for requiring that a recovery pass has already run: either
run it directly, if we're still in recovery, or if we're not in recovery
check if it has run recently and schedule it if it hasn't.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Author: Kent Overstreet

fs/bcachefs/errcode.h

@@ -182,9 +182,12 @@
 	x(BCH_ERR_fsck,			fsck_errors_not_fixed)			\
 	x(BCH_ERR_fsck,			fsck_repair_unimplemented)		\
 	x(BCH_ERR_fsck,			fsck_repair_impossible)			\
-	x(EINVAL,			restart_recovery)			\
-	x(EINVAL,			cannot_rewind_recovery)			\
+	x(EINVAL,			recovery_will_run)			\
+	x(BCH_ERR_recovery_will_run,	restart_recovery)			\
+	x(BCH_ERR_recovery_will_run,	cannot_rewind_recovery)			\
+	x(BCH_ERR_recovery_will_run,	recovery_pass_will_run)			\
 	x(0,				data_update_done)			\
+	x(0,				bkey_was_deleted)			\
 	x(BCH_ERR_data_update_done,	data_update_done_would_block)		\
 	x(BCH_ERR_data_update_done,	data_update_done_unwritten)		\
 	x(BCH_ERR_data_update_done,	data_update_done_no_writes_needed)	\

fs/bcachefs/recovery_passes.c

@@ -384,6 +384,35 @@ int bch2_run_explicit_recovery_pass(struct bch_fs *c,
 	return ret;
 }
 
+/*
+ * Returns 0 if @pass has run recently, otherwise one of
+ * -BCH_ERR_restart_recovery
+ * -BCH_ERR_recovery_pass_will_run
+ */
+int bch2_require_recovery_pass(struct bch_fs *c,
+			       struct printbuf *out,
+			       enum bch_recovery_pass pass)
+{
+	if (test_bit(BCH_FS_in_recovery, &c->flags) &&
+	    c->recovery.passes_complete & BIT_ULL(pass))
+		return 0;
+
+	guard(mutex)(&c->sb_lock);
+
+	if (bch2_recovery_pass_want_ratelimit(c, pass))
+		return 0;
+
+	enum bch_run_recovery_pass_flags flags = 0;
+	int ret = 0;
+
+	if (recovery_pass_needs_set(c, pass, &flags)) {
+		ret = __bch2_run_explicit_recovery_pass(c, out, pass, flags);
+		bch2_write_super(c);
+	}
+
+	return ret ?: bch_err_throw(c, recovery_pass_will_run);
+}
+
 int bch2_run_print_explicit_recovery_pass(struct bch_fs *c, enum bch_recovery_pass pass)
 {
 	enum bch_run_recovery_pass_flags flags = RUN_RECOVERY_PASS_nopersistent;

fs/bcachefs/recovery_passes.h

@@ -24,6 +24,9 @@ int bch2_run_explicit_recovery_pass(struct bch_fs *, struct printbuf *,
 				    enum bch_recovery_pass,
 				    enum bch_run_recovery_pass_flags);
 
+int bch2_require_recovery_pass(struct bch_fs *, struct printbuf *,
+			       enum bch_recovery_pass);
+
 int bch2_run_online_recovery_passes(struct bch_fs *, u64);
 int bch2_run_recovery_passes(struct bch_fs *, enum bch_recovery_pass);