1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * NVMe over Fabrics common host code. 4 * Copyright (c) 2015-2016 HGST, a Western Digital Company. 5 */ 6#ifndef _NVME_FABRICS_H 7#define _NVME_FABRICS_H 1 8 9#include <linux/in.h> 10#include <linux/inet.h> 11 12#define NVMF_MIN_QUEUE_SIZE 16 13#define NVMF_MAX_QUEUE_SIZE 1024 14#define NVMF_DEF_QUEUE_SIZE 128 15#define NVMF_DEF_RECONNECT_DELAY 10 16/* default to 600 seconds of reconnect attempts before giving up */ 17#define NVMF_DEF_CTRL_LOSS_TMO 600 18/* default is -1: the fail fast mechanism is disabled */ 19#define NVMF_DEF_FAIL_FAST_TMO -1 20 21/* 22 * Reserved one command for internal usage. This command is used for sending 23 * the connect command, as well as for the keep alive command on the admin 24 * queue once live. 25 */ 26#define NVMF_RESERVED_TAGS 1 27 28/* 29 * Define a host as seen by the target. We allocate one at boot, but also 30 * allow the override it when creating controllers. This is both to provide 31 * persistence of the Host NQN over multiple boots, and to allow using 32 * multiple ones, for example in a container scenario. Because we must not 33 * use different Host NQNs with the same Host ID we generate a Host ID and 34 * use this structure to keep track of the relation between the two. 35 */ 36struct nvmf_host { 37 struct kref ref; 38 struct list_head list; 39 char nqn[NVMF_NQN_SIZE]; 40 uuid_t id; 41}; 42 43/** 44 * enum nvmf_parsing_opts - used to define the sysfs parsing options used. 45 */ 46enum { 47 NVMF_OPT_ERR = 0, 48 NVMF_OPT_TRANSPORT = 1 << 0, 49 NVMF_OPT_NQN = 1 << 1, 50 NVMF_OPT_TRADDR = 1 << 2, 51 NVMF_OPT_TRSVCID = 1 << 3, 52 NVMF_OPT_QUEUE_SIZE = 1 << 4, 53 NVMF_OPT_NR_IO_QUEUES = 1 << 5, 54 NVMF_OPT_TL_RETRY_COUNT = 1 << 6, 55 NVMF_OPT_KATO = 1 << 7, 56 NVMF_OPT_HOSTNQN = 1 << 8, 57 NVMF_OPT_RECONNECT_DELAY = 1 << 9, 58 NVMF_OPT_HOST_TRADDR = 1 << 10, 59 NVMF_OPT_CTRL_LOSS_TMO = 1 << 11, 60 NVMF_OPT_HOST_ID = 1 << 12, 61 NVMF_OPT_DUP_CONNECT = 1 << 13, 62 NVMF_OPT_DISABLE_SQFLOW = 1 << 14, 63 NVMF_OPT_HDR_DIGEST = 1 << 15, 64 NVMF_OPT_DATA_DIGEST = 1 << 16, 65 NVMF_OPT_NR_WRITE_QUEUES = 1 << 17, 66 NVMF_OPT_NR_POLL_QUEUES = 1 << 18, 67 NVMF_OPT_TOS = 1 << 19, 68 NVMF_OPT_FAIL_FAST_TMO = 1 << 20, 69 NVMF_OPT_HOST_IFACE = 1 << 21, 70}; 71 72/** 73 * struct nvmf_ctrl_options - Used to hold the options specified 74 * with the parsing opts enum. 75 * @mask: Used by the fabrics library to parse through sysfs options 76 * on adding a NVMe controller. 77 * @transport: Holds the fabric transport "technology name" (for a lack of 78 * better description) that will be used by an NVMe controller 79 * being added. 80 * @subsysnqn: Hold the fully qualified NQN subystem name (format defined 81 * in the NVMe specification, "NVMe Qualified Names"). 82 * @traddr: The transport-specific TRADDR field for a port on the 83 * subsystem which is adding a controller. 84 * @trsvcid: The transport-specific TRSVCID field for a port on the 85 * subsystem which is adding a controller. 86 * @host_traddr: A transport-specific field identifying the NVME host port 87 * to use for the connection to the controller. 88 * @host_iface: A transport-specific field identifying the NVME host 89 * interface to use for the connection to the controller. 90 * @queue_size: Number of IO queue elements. 91 * @nr_io_queues: Number of controller IO queues that will be established. 92 * @reconnect_delay: Time between two consecutive reconnect attempts. 93 * @discovery_nqn: indicates if the subsysnqn is the well-known discovery NQN. 94 * @kato: Keep-alive timeout. 95 * @host: Virtual NVMe host, contains the NQN and Host ID. 96 * @max_reconnects: maximum number of allowed reconnect attempts before removing 97 * the controller, (-1) means reconnect forever, zero means remove 98 * immediately; 99 * @disable_sqflow: disable controller sq flow control 100 * @hdr_digest: generate/verify header digest (TCP) 101 * @data_digest: generate/verify data digest (TCP) 102 * @nr_write_queues: number of queues for write I/O 103 * @nr_poll_queues: number of queues for polling I/O 104 * @tos: type of service 105 * @fast_io_fail_tmo: Fast I/O fail timeout in seconds 106 */ 107struct nvmf_ctrl_options { 108 unsigned mask; 109 char *transport; 110 char *subsysnqn; 111 char *traddr; 112 char *trsvcid; 113 char *host_traddr; 114 char *host_iface; 115 size_t queue_size; 116 unsigned int nr_io_queues; 117 unsigned int reconnect_delay; 118 bool discovery_nqn; 119 bool duplicate_connect; 120 unsigned int kato; 121 struct nvmf_host *host; 122 int max_reconnects; 123 bool disable_sqflow; 124 bool hdr_digest; 125 bool data_digest; 126 unsigned int nr_write_queues; 127 unsigned int nr_poll_queues; 128 int tos; 129 int fast_io_fail_tmo; 130}; 131 132/* 133 * struct nvmf_transport_ops - used to register a specific 134 * fabric implementation of NVMe fabrics. 135 * @entry: Used by the fabrics library to add the new 136 * registration entry to its linked-list internal tree. 137 * @module: Transport module reference 138 * @name: Name of the NVMe fabric driver implementation. 139 * @required_opts: sysfs command-line options that must be specified 140 * when adding a new NVMe controller. 141 * @allowed_opts: sysfs command-line options that can be specified 142 * when adding a new NVMe controller. 143 * @create_ctrl(): function pointer that points to a non-NVMe 144 * implementation-specific fabric technology 145 * that would go into starting up that fabric 146 * for the purpose of conneciton to an NVMe controller 147 * using that fabric technology. 148 * 149 * Notes: 150 * 1. At minimum, 'required_opts' and 'allowed_opts' should 151 * be set to the same enum parsing options defined earlier. 152 * 2. create_ctrl() must be defined (even if it does nothing) 153 * 3. struct nvmf_transport_ops must be statically allocated in the 154 * modules .bss section so that a pure module_get on @module 155 * prevents the memory from beeing freed. 156 */ 157struct nvmf_transport_ops { 158 struct list_head entry; 159 struct module *module; 160 const char *name; 161 int required_opts; 162 int allowed_opts; 163 struct nvme_ctrl *(*create_ctrl)(struct device *dev, 164 struct nvmf_ctrl_options *opts); 165}; 166 167static inline bool 168nvmf_ctlr_matches_baseopts(struct nvme_ctrl *ctrl, 169 struct nvmf_ctrl_options *opts) 170{ 171 if (ctrl->state == NVME_CTRL_DELETING || 172 ctrl->state == NVME_CTRL_DEAD || 173 strcmp(opts->subsysnqn, ctrl->opts->subsysnqn) || 174 strcmp(opts->host->nqn, ctrl->opts->host->nqn) || 175 memcmp(&opts->host->id, &ctrl->opts->host->id, sizeof(uuid_t))) 176 return false; 177 178 return true; 179} 180 181int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val); 182int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val); 183int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val); 184int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl); 185int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid); 186int nvmf_register_transport(struct nvmf_transport_ops *ops); 187void nvmf_unregister_transport(struct nvmf_transport_ops *ops); 188void nvmf_free_options(struct nvmf_ctrl_options *opts); 189int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size); 190bool nvmf_should_reconnect(struct nvme_ctrl *ctrl); 191bool nvmf_ip_options_match(struct nvme_ctrl *ctrl, 192 struct nvmf_ctrl_options *opts); 193 194#endif /* _NVME_FABRICS_H */ 195