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 * Define a host as seen by the target. We allocate one at boot, but also 23 * allow the override it when creating controllers. This is both to provide 24 * persistence of the Host NQN over multiple boots, and to allow using 25 * multiple ones, for example in a container scenario. Because we must not 26 * use different Host NQNs with the same Host ID we generate a Host ID and 27 * use this structure to keep track of the relation between the two. 28 */ 29 struct nvmf_host { 30 struct kref ref; 31 struct list_head list; 32 char nqn[NVMF_NQN_SIZE]; 33 uuid_t id; 34 }; 35 36 /** 37 * enum nvmf_parsing_opts - used to define the sysfs parsing options used. 38 */ 39 enum { 40 NVMF_OPT_ERR = 0, 41 NVMF_OPT_TRANSPORT = 1 << 0, 42 NVMF_OPT_NQN = 1 << 1, 43 NVMF_OPT_TRADDR = 1 << 2, 44 NVMF_OPT_TRSVCID = 1 << 3, 45 NVMF_OPT_QUEUE_SIZE = 1 << 4, 46 NVMF_OPT_NR_IO_QUEUES = 1 << 5, 47 NVMF_OPT_TL_RETRY_COUNT = 1 << 6, 48 NVMF_OPT_KATO = 1 << 7, 49 NVMF_OPT_HOSTNQN = 1 << 8, 50 NVMF_OPT_RECONNECT_DELAY = 1 << 9, 51 NVMF_OPT_HOST_TRADDR = 1 << 10, 52 NVMF_OPT_CTRL_LOSS_TMO = 1 << 11, 53 NVMF_OPT_HOST_ID = 1 << 12, 54 NVMF_OPT_DUP_CONNECT = 1 << 13, 55 NVMF_OPT_DISABLE_SQFLOW = 1 << 14, 56 NVMF_OPT_HDR_DIGEST = 1 << 15, 57 NVMF_OPT_DATA_DIGEST = 1 << 16, 58 NVMF_OPT_NR_WRITE_QUEUES = 1 << 17, 59 NVMF_OPT_NR_POLL_QUEUES = 1 << 18, 60 NVMF_OPT_TOS = 1 << 19, 61 NVMF_OPT_FAIL_FAST_TMO = 1 << 20, 62 }; 63 64 /** 65 * struct nvmf_ctrl_options - Used to hold the options specified 66 * with the parsing opts enum. 67 * @mask: Used by the fabrics library to parse through sysfs options 68 * on adding a NVMe controller. 69 * @transport: Holds the fabric transport "technology name" (for a lack of 70 * better description) that will be used by an NVMe controller 71 * being added. 72 * @subsysnqn: Hold the fully qualified NQN subystem name (format defined 73 * in the NVMe specification, "NVMe Qualified Names"). 74 * @traddr: The transport-specific TRADDR field for a port on the 75 * subsystem which is adding a controller. 76 * @trsvcid: The transport-specific TRSVCID field for a port on the 77 * subsystem which is adding a controller. 78 * @host_traddr: A transport-specific field identifying the NVME host port 79 * to use for the connection to the controller. 80 * @queue_size: Number of IO queue elements. 81 * @nr_io_queues: Number of controller IO queues that will be established. 82 * @reconnect_delay: Time between two consecutive reconnect attempts. 83 * @discovery_nqn: indicates if the subsysnqn is the well-known discovery NQN. 84 * @kato: Keep-alive timeout. 85 * @host: Virtual NVMe host, contains the NQN and Host ID. 86 * @max_reconnects: maximum number of allowed reconnect attempts before removing 87 * the controller, (-1) means reconnect forever, zero means remove 88 * immediately; 89 * @disable_sqflow: disable controller sq flow control 90 * @hdr_digest: generate/verify header digest (TCP) 91 * @data_digest: generate/verify data digest (TCP) 92 * @nr_write_queues: number of queues for write I/O 93 * @nr_poll_queues: number of queues for polling I/O 94 * @tos: type of service 95 * @fast_io_fail_tmo: Fast I/O fail timeout in seconds 96 */ 97 struct nvmf_ctrl_options { 98 unsigned mask; 99 char *transport; 100 char *subsysnqn; 101 char *traddr; 102 char *trsvcid; 103 char *host_traddr; 104 size_t queue_size; 105 unsigned int nr_io_queues; 106 unsigned int reconnect_delay; 107 bool discovery_nqn; 108 bool duplicate_connect; 109 unsigned int kato; 110 struct nvmf_host *host; 111 int max_reconnects; 112 bool disable_sqflow; 113 bool hdr_digest; 114 bool data_digest; 115 unsigned int nr_write_queues; 116 unsigned int nr_poll_queues; 117 int tos; 118 int fast_io_fail_tmo; 119 }; 120 121 /* 122 * struct nvmf_transport_ops - used to register a specific 123 * fabric implementation of NVMe fabrics. 124 * @entry: Used by the fabrics library to add the new 125 * registration entry to its linked-list internal tree. 126 * @module: Transport module reference 127 * @name: Name of the NVMe fabric driver implementation. 128 * @required_opts: sysfs command-line options that must be specified 129 * when adding a new NVMe controller. 130 * @allowed_opts: sysfs command-line options that can be specified 131 * when adding a new NVMe controller. 132 * @create_ctrl(): function pointer that points to a non-NVMe 133 * implementation-specific fabric technology 134 * that would go into starting up that fabric 135 * for the purpose of conneciton to an NVMe controller 136 * using that fabric technology. 137 * 138 * Notes: 139 * 1. At minimum, 'required_opts' and 'allowed_opts' should 140 * be set to the same enum parsing options defined earlier. 141 * 2. create_ctrl() must be defined (even if it does nothing) 142 * 3. struct nvmf_transport_ops must be statically allocated in the 143 * modules .bss section so that a pure module_get on @module 144 * prevents the memory from beeing freed. 145 */ 146 struct nvmf_transport_ops { 147 struct list_head entry; 148 struct module *module; 149 const char *name; 150 int required_opts; 151 int allowed_opts; 152 struct nvme_ctrl *(*create_ctrl)(struct device *dev, 153 struct nvmf_ctrl_options *opts); 154 }; 155 156 static inline bool 157 nvmf_ctlr_matches_baseopts(struct nvme_ctrl *ctrl, 158 struct nvmf_ctrl_options *opts) 159 { 160 if (ctrl->state == NVME_CTRL_DELETING || 161 ctrl->state == NVME_CTRL_DEAD || 162 strcmp(opts->subsysnqn, ctrl->opts->subsysnqn) || 163 strcmp(opts->host->nqn, ctrl->opts->host->nqn) || 164 memcmp(&opts->host->id, &ctrl->opts->host->id, sizeof(uuid_t))) 165 return false; 166 167 return true; 168 } 169 170 int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val); 171 int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val); 172 int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val); 173 int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl); 174 int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid, bool poll); 175 int nvmf_register_transport(struct nvmf_transport_ops *ops); 176 void nvmf_unregister_transport(struct nvmf_transport_ops *ops); 177 void nvmf_free_options(struct nvmf_ctrl_options *opts); 178 int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size); 179 bool nvmf_should_reconnect(struct nvme_ctrl *ctrl); 180 blk_status_t nvmf_fail_nonready_command(struct nvme_ctrl *ctrl, 181 struct request *rq); 182 bool __nvmf_check_ready(struct nvme_ctrl *ctrl, struct request *rq, 183 bool queue_live); 184 bool nvmf_ip_options_match(struct nvme_ctrl *ctrl, 185 struct nvmf_ctrl_options *opts); 186 187 static inline bool nvmf_check_ready(struct nvme_ctrl *ctrl, struct request *rq, 188 bool queue_live) 189 { 190 if (likely(ctrl->state == NVME_CTRL_LIVE || 191 ctrl->state == NVME_CTRL_DELETING)) 192 return true; 193 return __nvmf_check_ready(ctrl, rq, queue_live); 194 } 195 196 #endif /* _NVME_FABRICS_H */ 197