[mirror_ubuntu-bionic-kernel.git] / drivers / nvme / host / fabrics.h

/*
 * NVMe over Fabrics common host code.
 * Copyright (c) 2015-2016 HGST, a Western Digital Company.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 */
#ifndef _NVME_FABRICS_H
#define _NVME_FABRICS_H 1

#include <linux/in.h>
#include <linux/inet.h>

#define NVMF_MIN_QUEUE_SIZE	16
#define NVMF_MAX_QUEUE_SIZE	1024
#define NVMF_DEF_QUEUE_SIZE	128
#define NVMF_DEF_RECONNECT_DELAY	10

/*
 * Define a host as seen by the target.  We allocate one at boot, but also
 * allow the override it when creating controllers.  This is both to provide
 * persistence of the Host NQN over multiple boots, and to allow using
 * multiple ones, for example in a container scenario.  Because we must not
 * use different Host NQNs with the same Host ID we generate a Host ID and
 * use this structure to keep track of the relation between the two.
 */
struct nvmf_host {
	struct kref		ref;
	struct list_head	list;
	char			nqn[NVMF_NQN_SIZE];
	uuid_be			id;
};

/**
 * enum nvmf_parsing_opts - used to define the sysfs parsing options used.
 */
enum {
	NVMF_OPT_ERR		= 0,
	NVMF_OPT_TRANSPORT	= 1 << 0,
	NVMF_OPT_NQN		= 1 << 1,
	NVMF_OPT_TRADDR		= 1 << 2,
	NVMF_OPT_TRSVCID	= 1 << 3,
	NVMF_OPT_QUEUE_SIZE	= 1 << 4,
	NVMF_OPT_NR_IO_QUEUES	= 1 << 5,
	NVMF_OPT_TL_RETRY_COUNT	= 1 << 6,
	NVMF_OPT_KATO		= 1 << 7,
	NVMF_OPT_HOSTNQN	= 1 << 8,
	NVMF_OPT_RECONNECT_DELAY = 1 << 9,
	NVMF_OPT_HOST_TRADDR	= 1 << 10,
};

/**
 * struct nvmf_ctrl_options - Used to hold the options specified
 *			      with the parsing opts enum.
 * @mask:	Used by the fabrics library to parse through sysfs options
 *		on adding a NVMe controller.
 * @transport:	Holds the fabric transport "technology name" (for a lack of
 *		better description) that will be used by an NVMe controller
 *		being added.
 * @subsysnqn:	Hold the fully qualified NQN subystem name (format defined
 *		in the NVMe specification, "NVMe Qualified Names").
 * @traddr:	The transport-specific TRADDR field for a port on the
 *              subsystem which is adding a controller.
 * @trsvcid:	The transport-specific TRSVCID field for a port on the
 *              subsystem which is adding a controller.
 * @host_traddr: A transport-specific field identifying the NVME host port
 *              to use for the connection to the controller.
 * @queue_size: Number of IO queue elements.
 * @nr_io_queues: Number of controller IO queues that will be established.
 * @reconnect_delay: Time between two consecutive reconnect attempts.
 * @discovery_nqn: indicates if the subsysnqn is the well-known discovery NQN.
 * @kato:	Keep-alive timeout.
 * @host:	Virtual NVMe host, contains the NQN and Host ID.
 */
struct nvmf_ctrl_options {
	unsigned		mask;
	char			*transport;
	char			*subsysnqn;
	char			*traddr;
	char			*trsvcid;
	char			*host_traddr;
	size_t			queue_size;
	unsigned int		nr_io_queues;
	unsigned int		reconnect_delay;
	bool			discovery_nqn;
	unsigned int		kato;
	struct nvmf_host	*host;
};

/*
 * struct nvmf_transport_ops - used to register a specific
 *			       fabric implementation of NVMe fabrics.
 * @entry:		Used by the fabrics library to add the new
 *			registration entry to its linked-list internal tree.
 * @name:		Name of the NVMe fabric driver implementation.
 * @required_opts:	sysfs command-line options that must be specified
 *			when adding a new NVMe controller.
 * @allowed_opts:	sysfs command-line options that can be specified
 *			when adding a new NVMe controller.
 * @create_ctrl():	function pointer that points to a non-NVMe
 *			implementation-specific fabric technology
 *			that would go into starting up that fabric
 *			for the purpose of conneciton to an NVMe controller
 *			using that fabric technology.
 *
 * Notes:
 *	1. At minimum, 'required_opts' and 'allowed_opts' should
 *	   be set to the same enum parsing options defined earlier.
 *	2. create_ctrl() must be defined (even if it does nothing)
 */
struct nvmf_transport_ops {
	struct list_head	entry;
	const char		*name;
	int			required_opts;
	int			allowed_opts;
	struct nvme_ctrl	*(*create_ctrl)(struct device *dev,
					struct nvmf_ctrl_options *opts);
};

int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val);
int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val);
int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val);
int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl);
int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid);
int nvmf_register_transport(struct nvmf_transport_ops *ops);
void nvmf_unregister_transport(struct nvmf_transport_ops *ops);
void nvmf_free_options(struct nvmf_ctrl_options *opts);
const char *nvmf_get_subsysnqn(struct nvme_ctrl *ctrl);
int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size);

#endif /* _NVME_FABRICS_H */
Commit	Line	Data
07bfcd09 CH	1	/*
	2	* NVMe over Fabrics common host code.
	3	* Copyright (c) 2015-2016 HGST, a Western Digital Company.
	4	*
	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms and conditions of the GNU General Public License,
	7	* version 2, as published by the Free Software Foundation.
	8	*
	9	* This program is distributed in the hope it will be useful, but WITHOUT
	10	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	11	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	12	* more details.
	13	*/
	14	#ifndef _NVME_FABRICS_H
	15	#define _NVME_FABRICS_H 1
	16
	17	#include <linux/in.h>
	18	#include <linux/inet.h>
	19
	20	#define NVMF_MIN_QUEUE_SIZE 16
	21	#define NVMF_MAX_QUEUE_SIZE 1024
	22	#define NVMF_DEF_QUEUE_SIZE 128
	23	#define NVMF_DEF_RECONNECT_DELAY 10
	24
	25	/*
	26	* Define a host as seen by the target. We allocate one at boot, but also
	27	* allow the override it when creating controllers. This is both to provide
	28	* persistence of the Host NQN over multiple boots, and to allow using
	29	* multiple ones, for example in a container scenario. Because we must not
	30	* use different Host NQNs with the same Host ID we generate a Host ID and
	31	* use this structure to keep track of the relation between the two.
	32	*/
	33	struct nvmf_host {
	34	struct kref ref;
	35	struct list_head list;
	36	char nqn[NVMF_NQN_SIZE];
7a665d2f	37	uuid_be id;
07bfcd09 CH	38	};
	39
	40	/**
	41	* enum nvmf_parsing_opts - used to define the sysfs parsing options used.
	42	*/
	43	enum {
	44	NVMF_OPT_ERR = 0,
	45	NVMF_OPT_TRANSPORT = 1 << 0,
	46	NVMF_OPT_NQN = 1 << 1,
	47	NVMF_OPT_TRADDR = 1 << 2,
	48	NVMF_OPT_TRSVCID = 1 << 3,
	49	NVMF_OPT_QUEUE_SIZE = 1 << 4,
	50	NVMF_OPT_NR_IO_QUEUES = 1 << 5,
	51	NVMF_OPT_TL_RETRY_COUNT = 1 << 6,
038bd4cb	52	NVMF_OPT_KATO = 1 << 7,
07bfcd09 CH	53	NVMF_OPT_HOSTNQN = 1 << 8,
07bfcd09 CH	54	NVMF_OPT_RECONNECT_DELAY = 1 << 9,
478bcb93	55	NVMF_OPT_HOST_TRADDR = 1 << 10,
07bfcd09 CH	56	};
	57
	58	/**
	59	* struct nvmf_ctrl_options - Used to hold the options specified
	60	* with the parsing opts enum.
	61	* @mask: Used by the fabrics library to parse through sysfs options
	62	* on adding a NVMe controller.
	63	* @transport: Holds the fabric transport "technology name" (for a lack of
	64	* better description) that will be used by an NVMe controller
	65	* being added.
	66	* @subsysnqn: Hold the fully qualified NQN subystem name (format defined
	67	* in the NVMe specification, "NVMe Qualified Names").
4a9f05c5 JS	68	* @traddr: The transport-specific TRADDR field for a port on the
	69	* subsystem which is adding a controller.
	70	* @trsvcid: The transport-specific TRSVCID field for a port on the
	71	* subsystem which is adding a controller.
478bcb93 JS	72	* @host_traddr: A transport-specific field identifying the NVME host port
478bcb93 JS	73	* to use for the connection to the controller.
07bfcd09 CH	74	* @queue_size: Number of IO queue elements.
07bfcd09 CH	75	* @nr_io_queues: Number of controller IO queues that will be established.
07bfcd09 CH	76	* @reconnect_delay: Time between two consecutive reconnect attempts.
07bfcd09 CH	77	* @discovery_nqn: indicates if the subsysnqn is the well-known discovery NQN.
038bd4cb	78	* @kato: Keep-alive timeout.
07bfcd09 CH	79	* @host: Virtual NVMe host, contains the NQN and Host ID.
	80	*/
	81	struct nvmf_ctrl_options {
	82	unsigned mask;
	83	char *transport;
	84	char *subsysnqn;
	85	char *traddr;
	86	char *trsvcid;
478bcb93	87	char *host_traddr;
07bfcd09 CH	88	size_t queue_size;
07bfcd09 CH	89	unsigned int nr_io_queues;
07bfcd09 CH	90	unsigned int reconnect_delay;
07bfcd09 CH	91	bool discovery_nqn;
038bd4cb	92	unsigned int kato;
07bfcd09 CH	93	struct nvmf_host *host;
	94	};
	95
	96	/*
	97	* struct nvmf_transport_ops - used to register a specific
	98	* fabric implementation of NVMe fabrics.
	99	* @entry: Used by the fabrics library to add the new
	100	* registration entry to its linked-list internal tree.
	101	* @name: Name of the NVMe fabric driver implementation.
	102	* @required_opts: sysfs command-line options that must be specified
	103	* when adding a new NVMe controller.
	104	* @allowed_opts: sysfs command-line options that can be specified
	105	* when adding a new NVMe controller.
	106	* @create_ctrl(): function pointer that points to a non-NVMe
	107	* implementation-specific fabric technology
	108	* that would go into starting up that fabric
	109	* for the purpose of conneciton to an NVMe controller
	110	* using that fabric technology.
	111	*
	112	* Notes:
	113	* 1. At minimum, 'required_opts' and 'allowed_opts' should
	114	* be set to the same enum parsing options defined earlier.
	115	* 2. create_ctrl() must be defined (even if it does nothing)
	116	*/
	117	struct nvmf_transport_ops {
	118	struct list_head entry;
	119	const char *name;
	120	int required_opts;
	121	int allowed_opts;
	122	struct nvme_ctrl (create_ctrl)(struct device *dev,
	123	struct nvmf_ctrl_options *opts);
	124	};
	125
	126	int nvmf_reg_read32(struct nvme_ctrl ctrl, u32 off, u32 val);
	127	int nvmf_reg_read64(struct nvme_ctrl ctrl, u32 off, u64 val);
	128	int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val);
	129	int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl);
	130	int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid);
e5a39dd8	131	int nvmf_register_transport(struct nvmf_transport_ops *ops);
07bfcd09 CH	132	void nvmf_unregister_transport(struct nvmf_transport_ops *ops);
	133	void nvmf_free_options(struct nvmf_ctrl_options *opts);
	134	const char nvmf_get_subsysnqn(struct nvme_ctrl ctrl);
	135	int nvmf_get_address(struct nvme_ctrl ctrl, char buf, int size);
	136
	137	#endif /* _NVME_FABRICS_H */