1 /* 2 * NVMe over Fabrics common host code. 3 * Copyright (c) 2015-2016 HGST, a Western Digital Company. 4 * 5 * This program is free software; you can redistribute it and/or modify it 6 * under the terms and conditions of the GNU General Public License, 7 * version 2, as published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 12 * more details. 13 */ 14 #ifndef _NVME_FABRICS_H 15 #define _NVME_FABRICS_H 1 16 17 #include <linux/in.h> 18 #include <linux/inet.h> 19 20 #define NVMF_MIN_QUEUE_SIZE 16 21 #define NVMF_MAX_QUEUE_SIZE 1024 22 #define NVMF_DEF_QUEUE_SIZE 128 23 #define NVMF_DEF_RECONNECT_DELAY 10 24 /* default to 600 seconds of reconnect attempts before giving up */ 25 #define NVMF_DEF_CTRL_LOSS_TMO 600 26 27 /* 28 * Define a host as seen by the target. We allocate one at boot, but also 29 * allow the override it when creating controllers. This is both to provide 30 * persistence of the Host NQN over multiple boots, and to allow using 31 * multiple ones, for example in a container scenario. Because we must not 32 * use different Host NQNs with the same Host ID we generate a Host ID and 33 * use this structure to keep track of the relation between the two. 34 */ 35 struct nvmf_host { 36 struct kref ref; 37 struct list_head list; 38 char nqn[NVMF_NQN_SIZE]; 39 uuid_t id; 40 }; 41 42 /** 43 * enum nvmf_parsing_opts - used to define the sysfs parsing options used. 44 */ 45 enum { 46 NVMF_OPT_ERR = 0, 47 NVMF_OPT_TRANSPORT = 1 << 0, 48 NVMF_OPT_NQN = 1 << 1, 49 NVMF_OPT_TRADDR = 1 << 2, 50 NVMF_OPT_TRSVCID = 1 << 3, 51 NVMF_OPT_QUEUE_SIZE = 1 << 4, 52 NVMF_OPT_NR_IO_QUEUES = 1 << 5, 53 NVMF_OPT_TL_RETRY_COUNT = 1 << 6, 54 NVMF_OPT_KATO = 1 << 7, 55 NVMF_OPT_HOSTNQN = 1 << 8, 56 NVMF_OPT_RECONNECT_DELAY = 1 << 9, 57 NVMF_OPT_HOST_TRADDR = 1 << 10, 58 NVMF_OPT_CTRL_LOSS_TMO = 1 << 11, 59 NVMF_OPT_HOST_ID = 1 << 12, 60 NVMF_OPT_DUP_CONNECT = 1 << 13, 61 NVMF_OPT_DISABLE_SQFLOW = 1 << 14, 62 NVMF_OPT_HDR_DIGEST = 1 << 15, 63 NVMF_OPT_DATA_DIGEST = 1 << 16, 64 NVMF_OPT_NR_WRITE_QUEUES = 1 << 17, 65 NVMF_OPT_NR_POLL_QUEUES = 1 << 18, 66 }; 67 68 /** 69 * struct nvmf_ctrl_options - Used to hold the options specified 70 * with the parsing opts enum. 71 * @mask: Used by the fabrics library to parse through sysfs options 72 * on adding a NVMe controller. 73 * @transport: Holds the fabric transport "technology name" (for a lack of 74 * better description) that will be used by an NVMe controller 75 * being added. 76 * @subsysnqn: Hold the fully qualified NQN subystem name (format defined 77 * in the NVMe specification, "NVMe Qualified Names"). 78 * @traddr: The transport-specific TRADDR field for a port on the 79 * subsystem which is adding a controller. 80 * @trsvcid: The transport-specific TRSVCID field for a port on the 81 * subsystem which is adding a controller. 82 * @host_traddr: A transport-specific field identifying the NVME host port 83 * to use for the connection to the controller. 84 * @queue_size: Number of IO queue elements. 85 * @nr_io_queues: Number of controller IO queues that will be established. 86 * @reconnect_delay: Time between two consecutive reconnect attempts. 87 * @discovery_nqn: indicates if the subsysnqn is the well-known discovery NQN. 88 * @kato: Keep-alive timeout. 89 * @host: Virtual NVMe host, contains the NQN and Host ID. 90 * @max_reconnects: maximum number of allowed reconnect attempts before removing 91 * the controller, (-1) means reconnect forever, zero means remove 92 * immediately; 93 * @disable_sqflow: disable controller sq flow control 94 * @hdr_digest: generate/verify header digest (TCP) 95 * @data_digest: generate/verify data digest (TCP) 96 * @nr_write_queues: number of queues for write I/O 97 * @nr_poll_queues: number of queues for polling I/O 98 */ 99 struct nvmf_ctrl_options { 100 unsigned mask; 101 char *transport; 102 char *subsysnqn; 103 char *traddr; 104 char *trsvcid; 105 char *host_traddr; 106 size_t queue_size; 107 unsigned int nr_io_queues; 108 unsigned int reconnect_delay; 109 bool discovery_nqn; 110 bool duplicate_connect; 111 unsigned int kato; 112 struct nvmf_host *host; 113 int max_reconnects; 114 bool disable_sqflow; 115 bool hdr_digest; 116 bool data_digest; 117 unsigned int nr_write_queues; 118 unsigned int nr_poll_queues; 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_ADMIN_ONLY)) 192 return true; 193 return __nvmf_check_ready(ctrl, rq, queue_live); 194 } 195 196 #endif /* _NVME_FABRICS_H */ 197