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 */ 36 struct 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 */ 46 enum { 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 }; 70 71 /** 72 * struct nvmf_ctrl_options - Used to hold the options specified 73 * with the parsing opts enum. 74 * @mask: Used by the fabrics library to parse through sysfs options 75 * on adding a NVMe controller. 76 * @transport: Holds the fabric transport "technology name" (for a lack of 77 * better description) that will be used by an NVMe controller 78 * being added. 79 * @subsysnqn: Hold the fully qualified NQN subystem name (format defined 80 * in the NVMe specification, "NVMe Qualified Names"). 81 * @traddr: The transport-specific TRADDR field for a port on the 82 * subsystem which is adding a controller. 83 * @trsvcid: The transport-specific TRSVCID field for a port on the 84 * subsystem which is adding a controller. 85 * @host_traddr: A transport-specific field identifying the NVME host port 86 * to use for the connection to the controller. 87 * @queue_size: Number of IO queue elements. 88 * @nr_io_queues: Number of controller IO queues that will be established. 89 * @reconnect_delay: Time between two consecutive reconnect attempts. 90 * @discovery_nqn: indicates if the subsysnqn is the well-known discovery NQN. 91 * @kato: Keep-alive timeout. 92 * @host: Virtual NVMe host, contains the NQN and Host ID. 93 * @max_reconnects: maximum number of allowed reconnect attempts before removing 94 * the controller, (-1) means reconnect forever, zero means remove 95 * immediately; 96 * @disable_sqflow: disable controller sq flow control 97 * @hdr_digest: generate/verify header digest (TCP) 98 * @data_digest: generate/verify data digest (TCP) 99 * @nr_write_queues: number of queues for write I/O 100 * @nr_poll_queues: number of queues for polling I/O 101 * @tos: type of service 102 * @fast_io_fail_tmo: Fast I/O fail timeout in seconds 103 */ 104 struct nvmf_ctrl_options { 105 unsigned mask; 106 char *transport; 107 char *subsysnqn; 108 char *traddr; 109 char *trsvcid; 110 char *host_traddr; 111 size_t queue_size; 112 unsigned int nr_io_queues; 113 unsigned int reconnect_delay; 114 bool discovery_nqn; 115 bool duplicate_connect; 116 unsigned int kato; 117 struct nvmf_host *host; 118 int max_reconnects; 119 bool disable_sqflow; 120 bool hdr_digest; 121 bool data_digest; 122 unsigned int nr_write_queues; 123 unsigned int nr_poll_queues; 124 int tos; 125 int fast_io_fail_tmo; 126 }; 127 128 /* 129 * struct nvmf_transport_ops - used to register a specific 130 * fabric implementation of NVMe fabrics. 131 * @entry: Used by the fabrics library to add the new 132 * registration entry to its linked-list internal tree. 133 * @module: Transport module reference 134 * @name: Name of the NVMe fabric driver implementation. 135 * @required_opts: sysfs command-line options that must be specified 136 * when adding a new NVMe controller. 137 * @allowed_opts: sysfs command-line options that can be specified 138 * when adding a new NVMe controller. 139 * @create_ctrl(): function pointer that points to a non-NVMe 140 * implementation-specific fabric technology 141 * that would go into starting up that fabric 142 * for the purpose of conneciton to an NVMe controller 143 * using that fabric technology. 144 * 145 * Notes: 146 * 1. At minimum, 'required_opts' and 'allowed_opts' should 147 * be set to the same enum parsing options defined earlier. 148 * 2. create_ctrl() must be defined (even if it does nothing) 149 * 3. struct nvmf_transport_ops must be statically allocated in the 150 * modules .bss section so that a pure module_get on @module 151 * prevents the memory from beeing freed. 152 */ 153 struct nvmf_transport_ops { 154 struct list_head entry; 155 struct module *module; 156 const char *name; 157 int required_opts; 158 int allowed_opts; 159 struct nvme_ctrl *(*create_ctrl)(struct device *dev, 160 struct nvmf_ctrl_options *opts); 161 }; 162 163 static inline bool 164 nvmf_ctlr_matches_baseopts(struct nvme_ctrl *ctrl, 165 struct nvmf_ctrl_options *opts) 166 { 167 if (ctrl->state == NVME_CTRL_DELETING || 168 ctrl->state == NVME_CTRL_DEAD || 169 strcmp(opts->subsysnqn, ctrl->opts->subsysnqn) || 170 strcmp(opts->host->nqn, ctrl->opts->host->nqn) || 171 memcmp(&opts->host->id, &ctrl->opts->host->id, sizeof(uuid_t))) 172 return false; 173 174 return true; 175 } 176 177 int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val); 178 int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val); 179 int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val); 180 int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl); 181 int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid, bool poll); 182 int nvmf_register_transport(struct nvmf_transport_ops *ops); 183 void nvmf_unregister_transport(struct nvmf_transport_ops *ops); 184 void nvmf_free_options(struct nvmf_ctrl_options *opts); 185 int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size); 186 bool nvmf_should_reconnect(struct nvme_ctrl *ctrl); 187 bool nvmf_ip_options_match(struct nvme_ctrl *ctrl, 188 struct nvmf_ctrl_options *opts); 189 190 #endif /* _NVME_FABRICS_H */ 191