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