1 files changed, 73 insertions, 0 deletions
diff --git a/sys/compat/linuxkpi/common/include/linux/seq_buf.h b/sys/compat/linuxkpi/common/include/linux/seq_buf.h
new file mode 100644
index 000000000000..d6246a40e6f7
--- /dev/null
+++ b/sys/compat/linuxkpi/common/include/linux/seq_buf.h
@@ -0,0 +1,73 @@
+/*
+ * Copyright (c) 2025-2026 The FreeBSD Foundation
+ * Copyright (c) 2025-2026 Jean-Sébastien Pédron <dumbbell@FreeBSD.org>
+ *
+ * This software was developed by Jean-Sébastien Pédron under sponsorship
+ * from the FreeBSD Foundation.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#ifndef _LINUXKPI_LINUX_SEQ_BUF_H_
+#define	_LINUXKPI_LINUX_SEQ_BUF_H_
+
+#include <linux/bug.h>
+#include <linux/minmax.h>
+#include <linux/seq_file.h>
+#include <linux/types.h>
+
+struct seq_buf {
+	char	*buffer;
+	size_t	 size;
+	size_t	 len;
+};
+
+#define DECLARE_SEQ_BUF(NAME, SIZE)			\
+	struct seq_buf NAME = {				\
+		.buffer = (char[SIZE]) { 0 },		\
+		.size = SIZE,				\
+	}
+
+static inline void
+seq_buf_clear(struct seq_buf *s)
+{
+	s->len = 0;
+	if (s->size > 0)
+		s->buffer[0] = '\0';
+}
+
+static inline void
+seq_buf_set_overflow(struct seq_buf *s)
+{
+	s->len = s->size + 1;
+}
+
+static inline bool
+seq_buf_has_overflowed(struct seq_buf *s)
+{
+	return (s->len > s->size);
+}
+
+static inline bool
+seq_buf_buffer_left(struct seq_buf *s)
+{
+	if (seq_buf_has_overflowed(s))
+		return (0);
+
+	return (s->size - s->len);
+}
+
+#define	seq_buf_init(s, buf, size) linuxkpi_seq_buf_init((s), (buf), (size))
+void linuxkpi_seq_buf_init(struct seq_buf *s, char *buf, unsigned int size);
+
+#define	seq_buf_printf(s, f, ...) linuxkpi_seq_buf_printf((s), (f), __VA_ARGS__)
+int linuxkpi_seq_buf_printf(struct seq_buf *s, const char *fmt, ...) \
+    __printflike(2, 3);
+
+#define	seq_buf_vprintf(s, f, a) linuxkpi_seq_buf_vprintf((s), (f), (a))
+int linuxkpi_seq_buf_vprintf(struct seq_buf *s, const char *fmt, va_list args);
+
+#define	seq_buf_str(s) linuxkpi_seq_buf_str((s))
+const char * linuxkpi_seq_buf_str(struct seq_buf *s);
+
+#endif