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 NVMF_OPT_HOST_IFACE = 1 << 21, 70 NVMF_OPT_DISCOVERY = 1 << 22, 71 }; 72 73 /** 74 * struct nvmf_ctrl_options - Used to hold the options specified 75 * with the parsing opts enum. 76 * @mask: Used by the fabrics library to parse through sysfs options 77 * on adding a NVMe controller. 78 * @transport: Holds the fabric transport "technology name" (for a lack of 79 * better description) that will be used by an NVMe controller 80 * being added. 81 * @subsysnqn: Hold the fully qualified NQN subystem name (format defined 82 * in the NVMe specification, "NVMe Qualified Names"). 83 * @traddr: The transport-specific TRADDR field for a port on the 84 * subsystem which is adding a controller. 85 * @trsvcid: The transport-specific TRSVCID field for a port on the 86 * subsystem which is adding a controller. 87 * @host_traddr: A transport-specific field identifying the NVME host port 88 * to use for the connection to the controller. 89 * @host_iface: A transport-specific field identifying the NVME host 90 * interface to use for the connection to the controller. 91 * @queue_size: Number of IO queue elements. 92 * @nr_io_queues: Number of controller IO queues that will be established. 93 * @reconnect_delay: Time between two consecutive reconnect attempts. 94 * @discovery_nqn: indicates if the subsysnqn is the well-known discovery NQN. 95 * @kato: Keep-alive timeout. 96 * @host: Virtual NVMe host, contains the NQN and Host ID. 97 * @max_reconnects: maximum number of allowed reconnect attempts before removing 98 * the controller, (-1) means reconnect forever, zero means remove 99 * immediately; 100 * @disable_sqflow: disable controller sq flow control 101 * @hdr_digest: generate/verify header digest (TCP) 102 * @data_digest: generate/verify data digest (TCP) 103 * @nr_write_queues: number of queues for write I/O 104 * @nr_poll_queues: number of queues for polling I/O 105 * @tos: type of service 106 * @fast_io_fail_tmo: Fast I/O fail timeout in seconds 107 */ 108 struct nvmf_ctrl_options { 109 unsigned mask; 110 char *transport; 111 char *subsysnqn; 112 char *traddr; 113 char *trsvcid; 114 char *host_traddr; 115 char *host_iface; 116 size_t queue_size; 117 unsigned int nr_io_queues; 118 unsigned int reconnect_delay; 119 bool discovery_nqn; 120 bool duplicate_connect; 121 unsigned int kato; 122 struct nvmf_host *host; 123 int max_reconnects; 124 bool disable_sqflow; 125 bool hdr_digest; 126 bool data_digest; 127 unsigned int nr_write_queues; 128 unsigned int nr_poll_queues; 129 int tos; 130 int fast_io_fail_tmo; 131 }; 132 133 /* 134 * struct nvmf_transport_ops - used to register a specific 135 * fabric implementation of NVMe fabrics. 136 * @entry: Used by the fabrics library to add the new 137 * registration entry to its linked-list internal tree. 138 * @module: Transport module reference 139 * @name: Name of the NVMe fabric driver implementation. 140 * @required_opts: sysfs command-line options that must be specified 141 * when adding a new NVMe controller. 142 * @allowed_opts: sysfs command-line options that can be specified 143 * when adding a new NVMe controller. 144 * @create_ctrl(): function pointer that points to a non-NVMe 145 * implementation-specific fabric technology 146 * that would go into starting up that fabric 147 * for the purpose of conneciton to an NVMe controller 148 * using that fabric technology. 149 * 150 * Notes: 151 * 1. At minimum, 'required_opts' and 'allowed_opts' should 152 * be set to the same enum parsing options defined earlier. 153 * 2. create_ctrl() must be defined (even if it does nothing) 154 * 3. struct nvmf_transport_ops must be statically allocated in the 155 * modules .bss section so that a pure module_get on @module 156 * prevents the memory from beeing freed. 157 */ 158 struct nvmf_transport_ops { 159 struct list_head entry; 160 struct module *module; 161 const char *name; 162 int required_opts; 163 int allowed_opts; 164 struct nvme_ctrl *(*create_ctrl)(struct device *dev, 165 struct nvmf_ctrl_options *opts); 166 }; 167 168 static inline bool 169 nvmf_ctlr_matches_baseopts(struct nvme_ctrl *ctrl, 170 struct nvmf_ctrl_options *opts) 171 { 172 if (ctrl->state == NVME_CTRL_DELETING || 173 ctrl->state == NVME_CTRL_DELETING_NOIO || 174 ctrl->state == NVME_CTRL_DEAD || 175 strcmp(opts->subsysnqn, ctrl->opts->subsysnqn) || 176 strcmp(opts->host->nqn, ctrl->opts->host->nqn) || 177 memcmp(&opts->host->id, &ctrl->opts->host->id, sizeof(uuid_t))) 178 return false; 179 180 return true; 181 } 182 183 static inline char *nvmf_ctrl_subsysnqn(struct nvme_ctrl *ctrl) 184 { 185 if (!ctrl->subsys) 186 return ctrl->opts->subsysnqn; 187 return ctrl->subsys->subnqn; 188 } 189 190 int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val); 191 int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val); 192 int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val); 193 int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl); 194 int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid); 195 int nvmf_register_transport(struct nvmf_transport_ops *ops); 196 void nvmf_unregister_transport(struct nvmf_transport_ops *ops); 197 void nvmf_free_options(struct nvmf_ctrl_options *opts); 198 int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size); 199 bool nvmf_should_reconnect(struct nvme_ctrl *ctrl); 200 bool nvmf_ip_options_match(struct nvme_ctrl *ctrl, 201 struct nvmf_ctrl_options *opts); 202 203 #endif /* _NVME_FABRICS_H */ 204