lib/bdev: Added spdk_bdev_get_zone_info() command

spdk_bdev_get_zone_info() is used for retriving
information about zones inside zoned namespace.

Change-Id: I8f931505245e984c0b1ee35ed6592c978ee47544
Signed-off-by: Wojciech Malikowski <wojciech.malikowski@intel.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/460643
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>

include/spdk/bdev.h

@@ -126,6 +126,7 @@ enum spdk_bdev_io_type {
 	SPDK_BDEV_IO_TYPE_NVME_IO_MD,
 	SPDK_BDEV_IO_TYPE_WRITE_ZEROES,
 	SPDK_BDEV_IO_TYPE_ZCOPY,
+	SPDK_BDEV_IO_TYPE_GET_ZONE_INFO,
 	SPDK_BDEV_NUM_IO_TYPES /* Keep last */
 };
 

include/spdk/bdev_module.h

@@ -43,6 +43,7 @@
 #include "spdk/stdinc.h"
 
 #include "spdk/bdev.h"
+#include "spdk/bdev_zone.h"
 #include "spdk/queue.h"
 #include "spdk/scsi_spec.h"
 #include "spdk/thread.h"
@@ -512,6 +513,16 @@ struct spdk_bdev_io {
 			/* meta data buffer size to transfer */
 			size_t md_len;
 		} nvme_passthru;
+		struct {
+			/* First logical block of a zone */
+			uint64_t zone_id;
+
+			/* Number of zones */
+			uint32_t num_zones;
+
+			/* The data buffer */
+			void *buf;
+		} zone_mgmt;
 	} u;
 
 	/** It may be used by modules to put the bdev_io into its own list. */

include/spdk/bdev_zone.h

@@ -39,6 +39,7 @@
 #define SPDK_BDEV_ZONE_H
 
 #include "spdk/stdinc.h"
+#include "spdk/bdev.h"
 
 /**
  * \brief SPDK block device.
@@ -48,6 +49,22 @@
 
 struct spdk_bdev;
 
+enum spdk_bdev_zone_state {
+	SPDK_BDEV_ZONE_STATE_EMPTY,
+	SPDK_BDEV_ZONE_STATE_OPEN,
+	SPDK_BDEV_ZONE_STATE_FULL,
+	SPDK_BDEV_ZONE_STATE_CLOSED,
+	SPDK_BDEV_ZONE_STATE_READ_ONLY,
+	SPDK_BDEV_ZONE_STATE_OFFLINE
+};
+
+struct spdk_bdev_zone_info {
+	uint64_t			zone_id;
+	uint64_t			write_pointer;
+	uint64_t			capacity;
+	enum spdk_bdev_zone_state	state;
+};
+
 /**
  * Get device zone size in logical blocks.
  *
@@ -74,4 +91,26 @@ uint32_t spdk_bdev_get_max_open_zones(const struct spdk_bdev *bdev);
  */
 uint32_t spdk_bdev_get_optimal_open_zones(const struct spdk_bdev *bdev);
 
+/**
+ * Submit a get_zone_info request to the bdev.
+ *
+ * \ingroup bdev_io_submit_functions
+ *
+ * \param desc Block device descriptor.
+ * \param ch I/O channel. Obtained by calling spdk_bdev_get_io_channel().
+ * \param zone_id First logical block of a zone.
+ * \param num_zones Number of consecutive zones info to retrieve.
+ * \param info Pointer to array capable of storing num_zones elements.
+ * \param cb Called when the request is complete.
+ * \param cb_arg Argument passed to cb.
+ *
+ * \return 0 on success. On success, the callback will always
+ * be called (even if the request ultimately failed). Return
+ * negated errno on failure, in which case the callback will not be called.
+ *   * -ENOMEM - spdk_bdev_io buffer cannot be allocated
+ */
+int spdk_bdev_get_zone_info(struct spdk_bdev_desc *desc, struct spdk_io_channel *ch,
+			    uint64_t zone_id, size_t num_zones, struct spdk_bdev_zone_info *info,
+			    spdk_bdev_io_completion_cb cb, void *cb_arg);
+
 #endif /* SPDK_BDEV_ZONE_H */

lib/bdev/bdev_zone.c

@@ -36,6 +36,8 @@
 #include "spdk/bdev_zone.h"
 #include "spdk/bdev_module.h"
 
+#include "bdev_internal.h"
+
 uint64_t
 spdk_bdev_get_zone_size(const struct spdk_bdev *bdev)
 {
@@ -53,3 +55,29 @@ spdk_bdev_get_optimal_open_zones(const struct spdk_bdev *bdev)
 {
 	return bdev->optimal_open_zones;
 }
+
+int
+spdk_bdev_get_zone_info(struct spdk_bdev_desc *desc, struct spdk_io_channel *ch,
+			uint64_t zone_id, size_t num_zones, struct spdk_bdev_zone_info *info,
+			spdk_bdev_io_completion_cb cb, void *cb_arg)
+{
+	struct spdk_bdev *bdev = spdk_bdev_desc_get_bdev(desc);
+	struct spdk_bdev_io *bdev_io;
+	struct spdk_bdev_channel *channel = spdk_io_channel_get_ctx(ch);
+
+	bdev_io = spdk_bdev_get_io(channel);
+	if (!bdev_io) {
+		return -ENOMEM;
+	}
+
+	bdev_io->internal.ch = channel;
+	bdev_io->internal.desc = desc;
+	bdev_io->type = SPDK_BDEV_IO_TYPE_GET_ZONE_INFO;
+	bdev_io->u.zone_mgmt.zone_id = zone_id;
+	bdev_io->u.zone_mgmt.num_zones = num_zones;
+	bdev_io->u.zone_mgmt.buf = info;
+	spdk_bdev_io_init(bdev_io, bdev, cb_arg, cb);
+
+	spdk_bdev_io_submit(bdev_io);
+	return 0;
+}