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 NVMF_OPT_TOS = 1 << 19, 59 }; 60 61 /** 62 * struct nvmf_ctrl_options - Used to hold the options specified 63 * with the parsing opts enum. 64 * @mask: Used by the fabrics library to parse through sysfs options 65 * on adding a NVMe controller. 66 * @transport: Holds the fabric transport "technology name" (for a lack of 67 * better description) that will be used by an NVMe controller 68 * being added. 69 * @subsysnqn: Hold the fully qualified NQN subystem name (format defined 70 * in the NVMe specification, "NVMe Qualified Names"). 71 * @traddr: The transport-specific TRADDR field for a port on the 72 * subsystem which is adding a controller. 73 * @trsvcid: The transport-specific TRSVCID field for a port on the 74 * subsystem which is adding a controller. 75 * @host_traddr: A transport-specific field identifying the NVME host port 76 * to use for the connection to the controller. 77 * @queue_size: Number of IO queue elements. 78 * @nr_io_queues: Number of controller IO queues that will be established. 79 * @reconnect_delay: Time between two consecutive reconnect attempts. 80 * @discovery_nqn: indicates if the subsysnqn is the well-known discovery NQN. 81 * @kato: Keep-alive timeout. 82 * @host: Virtual NVMe host, contains the NQN and Host ID. 83 * @max_reconnects: maximum number of allowed reconnect attempts before removing 84 * the controller, (-1) means reconnect forever, zero means remove 85 * immediately; 86 * @disable_sqflow: disable controller sq flow control 87 * @hdr_digest: generate/verify header digest (TCP) 88 * @data_digest: generate/verify data digest (TCP) 89 * @nr_write_queues: number of queues for write I/O 90 * @nr_poll_queues: number of queues for polling I/O 91 * @tos: type of service 92 */ 93 struct nvmf_ctrl_options { 94 unsigned mask; 95 char *transport; 96 char *subsysnqn; 97 char *traddr; 98 char *trsvcid; 99 char *host_traddr; 100 size_t queue_size; 101 unsigned int nr_io_queues; 102 unsigned int reconnect_delay; 103 bool discovery_nqn; 104 bool duplicate_connect; 105 unsigned int kato; 106 struct nvmf_host *host; 107 int max_reconnects; 108 bool disable_sqflow; 109 bool hdr_digest; 110 bool data_digest; 111 unsigned int nr_write_queues; 112 unsigned int nr_poll_queues; 113 int tos; 114 }; 115 116 /* 117 * struct nvmf_transport_ops - used to register a specific 118 * fabric implementation of NVMe fabrics. 119 * @entry: Used by the fabrics library to add the new 120 * registration entry to its linked-list internal tree. 121 * @module: Transport module reference 122 * @name: Name of the NVMe fabric driver implementation. 123 * @required_opts: sysfs command-line options that must be specified 124 * when adding a new NVMe controller. 125 * @allowed_opts: sysfs command-line options that can be specified 126 * when adding a new NVMe controller. 127 * @create_ctrl(): function pointer that points to a non-NVMe 128 * implementation-specific fabric technology 129 * that would go into starting up that fabric 130 * for the purpose of conneciton to an NVMe controller 131 * using that fabric technology. 132 * 133 * Notes: 134 * 1. At minimum, 'required_opts' and 'allowed_opts' should 135 * be set to the same enum parsing options defined earlier. 136 * 2. create_ctrl() must be defined (even if it does nothing) 137 * 3. struct nvmf_transport_ops must be statically allocated in the 138 * modules .bss section so that a pure module_get on @module 139 * prevents the memory from beeing freed. 140 */ 141 struct nvmf_transport_ops { 142 struct list_head entry; 143 struct module *module; 144 const char *name; 145 int required_opts; 146 int allowed_opts; 147 struct nvme_ctrl *(*create_ctrl)(struct device *dev, 148 struct nvmf_ctrl_options *opts); 149 }; 150 151 static inline bool 152 nvmf_ctlr_matches_baseopts(struct nvme_ctrl *ctrl, 153 struct nvmf_ctrl_options *opts) 154 { 155 if (ctrl->state == NVME_CTRL_DELETING || 156 ctrl->state == NVME_CTRL_DEAD || 157 strcmp(opts->subsysnqn, ctrl->opts->subsysnqn) || 158 strcmp(opts->host->nqn, ctrl->opts->host->nqn) || 159 memcmp(&opts->host->id, &ctrl->opts->host->id, sizeof(uuid_t))) 160 return false; 161 162 return true; 163 } 164 165 int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val); 166 int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val); 167 int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val); 168 int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl); 169 int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid, bool poll); 170 int nvmf_register_transport(struct nvmf_transport_ops *ops); 171 void nvmf_unregister_transport(struct nvmf_transport_ops *ops); 172 void nvmf_free_options(struct nvmf_ctrl_options *opts); 173 int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size); 174 bool nvmf_should_reconnect(struct nvme_ctrl *ctrl); 175 blk_status_t nvmf_fail_nonready_command(struct nvme_ctrl *ctrl, 176 struct request *rq); 177 bool __nvmf_check_ready(struct nvme_ctrl *ctrl, struct request *rq, 178 bool queue_live); 179 bool nvmf_ip_options_match(struct nvme_ctrl *ctrl, 180 struct nvmf_ctrl_options *opts); 181 182 static inline bool nvmf_check_ready(struct nvme_ctrl *ctrl, struct request *rq, 183 bool queue_live) 184 { 185 if (likely(ctrl->state == NVME_CTRL_LIVE || 186 ctrl->state == NVME_CTRL_DELETING)) 187 return true; 188 return __nvmf_check_ready(ctrl, rq, queue_live); 189 } 190 191 #endif /* _NVME_FABRICS_H */ 192