/* SPDX-License-Identifier: GPL-2.0 */
/*
* NVMe over Fabrics common host code.
* Copyright (c) 2015-2016 HGST, a Western Digital Company.
*/
#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
/* default to 600 seconds of reconnect attempts before giving up */
#define NVMF_DEF_CTRL_LOSS_TMO 600
/* default is -1: the fail fast mechanism is disabled */
#define NVMF_DEF_FAIL_FAST_TMO -1
/*
* 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_t 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,
NVMF_OPT_CTRL_LOSS_TMO = 1 << 11,
NVMF_OPT_HOST_ID = 1 << 12,
NVMF_OPT_DUP_CONNECT = 1 << 13,
NVMF_OPT_DISABLE_SQFLOW = 1 << 14,
NVMF_OPT_HDR_DIGEST = 1 << 15,
NVMF_OPT_DATA_DIGEST = 1 << 16,
NVMF_OPT_NR_WRITE_QUEUES = 1 << 17,
NVMF_OPT_NR_POLL_QUEUES = 1 << 18,
NVMF_OPT_TOS = 1 << 19,
NVMF_OPT_FAIL_FAST_TMO = 1 << 20,
NVMF_OPT_HOST_IFACE = 1 << 21,
NVMF_OPT_DISCOVERY = 1 << 22,
NVMF_OPT_DHCHAP_SECRET = 1 << 23,
NVMF_OPT_DHCHAP_CTRL_SECRET = 1 << 24,
NVMF_OPT_TLS = 1 << 25,
NVMF_OPT_KEYRING = 1 << 26,
NVMF_OPT_TLS_KEY = 1 << 27,
};
/**
* 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.
* @max_reconnects: maximum number of allowed reconnect attempts before removing
* the controller, (-1) means reconnect forever, zero means remove
* immediately;
* @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.
* @host_iface: A transport-specific field identifying the NVME host
* interface 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.
* @dhchap_secret: DH-HMAC-CHAP secret
* @dhchap_ctrl_secret: DH-HMAC-CHAP controller secret for bi-directional
* authentication
* @keyring: Keyring to use for key lookups
* @tls_key: TLS key for encrypted connections (TCP)
* @tls: Start TLS encrypted connections (TCP)
* @disable_sqflow: disable controller sq flow control
* @hdr_digest: generate/verify header digest (TCP)
* @data_digest: generate/verify data digest (TCP)
* @nr_write_queues: number of queues for write I/O
* @nr_poll_queues: number of queues for polling I/O
* @tos: type of service
* @fast_io_fail_tmo: Fast I/O fail timeout in seconds
*/
struct nvmf_ctrl_options {
unsigned mask;
int max_reconnects;
char *transport;
char *subsysnqn;
char *traddr;
char *trsvcid;
char *host_traddr;
char *host_iface;
size_t queue_size;
unsigned int nr_io_queues;
unsigned int reconnect_delay;
bool discovery_nqn;
bool duplicate_connect;
unsigned int kato;
struct nvmf_host *host;
char *dhchap_secret;
char *dhchap_ctrl_secret;
struct key *keyring;
struct key *tls_key;
bool tls;
bool disable_sqflow;
bool hdr_digest;
bool data_digest;
unsigned int nr_write_queues;
unsigned int nr_poll_queues;
int tos;
int fast_io_fail_tmo;
};
/*
* 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.
* @module: Transport module reference
* @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)
* 3. struct nvmf_transport_ops must be statically allocated in the
* modules .bss section so that a pure module_get on @module
* prevents the memory from beeing freed.
*/
struct nvmf_transport_ops {
struct list_head entry;
struct module *module;
const char *name;
int required_opts;
int allowed_opts;
struct nvme_ctrl *(*create_ctrl)(struct device *dev,
struct nvmf_ctrl_options *opts);
};
static inline bool
nvmf_ctlr_matches_baseopts(struct nvme_ctrl *ctrl,
struct nvmf_ctrl_options *opts)
{
enum nvme_ctrl_state state = nvme_ctrl_state(ctrl);
if (state == NVME_CTRL_DELETING ||
state == NVME_CTRL_DELETING_NOIO ||
state == NVME_CTRL_DEAD ||
strcmp(opts->subsysnqn, ctrl->opts->subsysnqn) ||
strcmp(opts->host->nqn, ctrl->opts->host->nqn) ||
!uuid_equal(&opts->host->id, &ctrl->opts->host->id))
return false;
return true;
}
static inline char *nvmf_ctrl_subsysnqn(struct nvme_ctrl *ctrl)
{
if (!ctrl->subsys ||
!strcmp(ctrl->opts->subsysnqn, NVME_DISC_SUBSYS_NAME))
return ctrl->opts->subsysnqn;
return ctrl->subsys->subnqn;
}
static inline void nvmf_complete_timed_out_request(struct request *rq)
{
if (blk_mq_request_started(rq) && !blk_mq_request_completed(rq)) {
nvme_req(rq)->status = NVME_SC_HOST_ABORTED_CMD;
blk_mq_complete_request(rq);
}
}
static inline unsigned int nvmf_nr_io_queues(struct nvmf_ctrl_options *opts)
{
return min(opts->nr_io_queues, num_online_cpus()) +
min(opts->nr_write_queues, num_online_cpus()) +
min(opts->nr_poll_queues, num_online_cpus());
}
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_subsystem_reset(struct nvme_ctrl *ctrl);
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);
int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size);
bool nvmf_should_reconnect(struct nvme_ctrl *ctrl, int status);
bool nvmf_ip_options_match(struct nvme_ctrl *ctrl,
struct nvmf_ctrl_options *opts);
void nvmf_set_io_queues(struct nvmf_ctrl_options *opts, u32 nr_io_queues,
u32 io_queues[HCTX_MAX_TYPES]);
void nvmf_map_queues(struct blk_mq_tag_set *set, struct nvme_ctrl *ctrl,
u32 io_queues[HCTX_MAX_TYPES]);
#endif /* _NVME_FABRICS_H */