[PATCH v3 3/6] libfrog: introduce xfrog_report_zones

[Damien Le Moal <dlemoal@kernel.org>]

Define the new helper function xfrog_report_zones() to report zones of
a zoned block device. This function is implemented in the new file
libfrog/zones.c and defined in the header file libfrog/zones.h.

xfrog_report_zones() allocates and returns a struct blk_zone_report
structure. It is the responsibility of the caller to free this
structure after use.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
---
 libfrog/Makefile |  6 ++++--
 libfrog/zones.c  | 42 ++++++++++++++++++++++++++++++++++++++++++
 libfrog/zones.h  | 13 +++++++++++++
 3 files changed, 59 insertions(+), 2 deletions(-)
 create mode 100644 libfrog/zones.c
 create mode 100644 libfrog/zones.h

diff --git a/libfrog/Makefile b/libfrog/Makefile
index 268fa26638d7..9f405ffe3475 100644
--- a/libfrog/Makefile
+++ b/libfrog/Makefile
@@ -35,7 +35,8 @@ radix-tree.c \
 randbytes.c \
 scrub.c \
 util.c \
-workqueue.c
+workqueue.c \
+zones.c
 
 HFILES = \
 avl64.h \
@@ -65,7 +66,8 @@ radix-tree.h \
 randbytes.h \
 scrub.h \
 statx.h \
-workqueue.h
+workqueue.h \
+zones.h
 
 GETTEXT_PY = \
 	gettext.py
diff --git a/libfrog/zones.c b/libfrog/zones.c
new file mode 100644
index 000000000000..0187edce5fa4
--- /dev/null
+++ b/libfrog/zones.c
@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2025, Western Digital Corporation or its affiliates.
+ */
+#include "platform_defs.h"
+#include "zones.h"
+#include <sys/ioctl.h>
+
+/* random size that allows efficient processing */
+#define ZONES_PER_REPORT		16384
+
+struct blk_zone_report	*
+xfrog_report_zones(
+	int			fd,
+	uint64_t		sector)
+{
+	struct blk_zone_report	*rep;
+	size_t			rep_size;
+	int			ret;
+
+	rep_size = sizeof(struct blk_zone_report) +
+		   sizeof(struct blk_zone) * ZONES_PER_REPORT;
+	rep = calloc(1, rep_size);
+	if (!rep) {
+		fprintf(stderr,
+_("Failed to allocate memory for reporting zones.\n"));
+		return NULL;
+	}
+
+	rep->sector = sector;
+	rep->nr_zones = ZONES_PER_REPORT;
+
+	ret = ioctl(fd, BLKREPORTZONE, rep);
+	if (ret) {
+		fprintf(stderr,
+_("ioctl(BLKREPORTZONE) failed: %d!\n"), -errno);
+		free(rep);
+		return NULL;
+	}
+
+	return rep;
+}
diff --git a/libfrog/zones.h b/libfrog/zones.h
new file mode 100644
index 000000000000..66df7a426a27
--- /dev/null
+++ b/libfrog/zones.h
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2025, Western Digital Corporation or its affiliates.
+ */
+#ifndef __LIBFROG_ZONE_H__
+#define __LIBFROG_ZONE_H__
+
+#include <stdint.h>
+#include <linux/blkzoned.h>
+
+struct blk_zone_report	*xfrog_report_zones(int	fd, uint64_t sector);
+
+#endif /* __LIBFROG_ZONE_H__ */
-- 
2.52.0