/* * 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 #include #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 /* * 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, }; /** * 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. * @max_reconnects: maximum number of allowed reconnect attempts before removing * the controller, (-1) means reconnect forever, zero means remove * immediately; */ 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; bool duplicate_connect; unsigned int kato; struct nvmf_host *host; int max_reconnects; bool disable_sqflow; bool hdr_digest; bool data_digest; }; /* * 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) { if (ctrl->state == NVME_CTRL_DELETING || ctrl->state == NVME_CTRL_DEAD || strcmp(opts->subsysnqn, ctrl->opts->subsysnqn) || strcmp(opts->host->nqn, ctrl->opts->host->nqn) || memcmp(&opts->host->id, &ctrl->opts->host->id, sizeof(uuid_t))) return false; return true; } 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); int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size); bool nvmf_should_reconnect(struct nvme_ctrl *ctrl); blk_status_t nvmf_fail_nonready_command(struct nvme_ctrl *ctrl, struct request *rq); bool __nvmf_check_ready(struct nvme_ctrl *ctrl, struct request *rq, bool queue_live); bool nvmf_ip_options_match(struct nvme_ctrl *ctrl, struct nvmf_ctrl_options *opts); static inline bool nvmf_check_ready(struct nvme_ctrl *ctrl, struct request *rq, bool queue_live) { if (likely(ctrl->state == NVME_CTRL_LIVE || ctrl->state == NVME_CTRL_ADMIN_ONLY)) return true; return __nvmf_check_ready(ctrl, rq, queue_live); } #endif /* _NVME_FABRICS_H */