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 25 /* 26 * Define a host as seen by the target. We allocate one at boot, but also 27 * allow the override it when creating controllers. This is both to provide 28 * persistence of the Host NQN over multiple boots, and to allow using 29 * multiple ones, for example in a container scenario. Because we must not 30 * use different Host NQNs with the same Host ID we generate a Host ID and 31 * use this structure to keep track of the relation between the two. 32 */ 33 struct nvmf_host { 34 struct kref ref; 35 struct list_head list; 36 char nqn[NVMF_NQN_SIZE]; 37 uuid_be id; 38 }; 39 40 /** 41 * enum nvmf_parsing_opts - used to define the sysfs parsing options used. 42 */ 43 enum { 44 NVMF_OPT_ERR = 0, 45 NVMF_OPT_TRANSPORT = 1 << 0, 46 NVMF_OPT_NQN = 1 << 1, 47 NVMF_OPT_TRADDR = 1 << 2, 48 NVMF_OPT_TRSVCID = 1 << 3, 49 NVMF_OPT_QUEUE_SIZE = 1 << 4, 50 NVMF_OPT_NR_IO_QUEUES = 1 << 5, 51 NVMF_OPT_TL_RETRY_COUNT = 1 << 6, 52 NVMF_OPT_KATO = 1 << 7, 53 NVMF_OPT_HOSTNQN = 1 << 8, 54 NVMF_OPT_RECONNECT_DELAY = 1 << 9, 55 NVMF_OPT_HOST_TRADDR = 1 << 10, 56 }; 57 58 /** 59 * struct nvmf_ctrl_options - Used to hold the options specified 60 * with the parsing opts enum. 61 * @mask: Used by the fabrics library to parse through sysfs options 62 * on adding a NVMe controller. 63 * @transport: Holds the fabric transport "technology name" (for a lack of 64 * better description) that will be used by an NVMe controller 65 * being added. 66 * @subsysnqn: Hold the fully qualified NQN subystem name (format defined 67 * in the NVMe specification, "NVMe Qualified Names"). 68 * @traddr: The transport-specific TRADDR field for a port on the 69 * subsystem which is adding a controller. 70 * @trsvcid: The transport-specific TRSVCID field for a port on the 71 * subsystem which is adding a controller. 72 * @host_traddr: A transport-specific field identifying the NVME host port 73 * to use for the connection to the controller. 74 * @queue_size: Number of IO queue elements. 75 * @nr_io_queues: Number of controller IO queues that will be established. 76 * @reconnect_delay: Time between two consecutive reconnect attempts. 77 * @discovery_nqn: indicates if the subsysnqn is the well-known discovery NQN. 78 * @kato: Keep-alive timeout. 79 * @host: Virtual NVMe host, contains the NQN and Host ID. 80 */ 81 struct nvmf_ctrl_options { 82 unsigned mask; 83 char *transport; 84 char *subsysnqn; 85 char *traddr; 86 char *trsvcid; 87 char *host_traddr; 88 size_t queue_size; 89 unsigned int nr_io_queues; 90 unsigned int reconnect_delay; 91 bool discovery_nqn; 92 unsigned int kato; 93 struct nvmf_host *host; 94 }; 95 96 /* 97 * struct nvmf_transport_ops - used to register a specific 98 * fabric implementation of NVMe fabrics. 99 * @entry: Used by the fabrics library to add the new 100 * registration entry to its linked-list internal tree. 101 * @name: Name of the NVMe fabric driver implementation. 102 * @required_opts: sysfs command-line options that must be specified 103 * when adding a new NVMe controller. 104 * @allowed_opts: sysfs command-line options that can be specified 105 * when adding a new NVMe controller. 106 * @create_ctrl(): function pointer that points to a non-NVMe 107 * implementation-specific fabric technology 108 * that would go into starting up that fabric 109 * for the purpose of conneciton to an NVMe controller 110 * using that fabric technology. 111 * 112 * Notes: 113 * 1. At minimum, 'required_opts' and 'allowed_opts' should 114 * be set to the same enum parsing options defined earlier. 115 * 2. create_ctrl() must be defined (even if it does nothing) 116 */ 117 struct nvmf_transport_ops { 118 struct list_head entry; 119 const char *name; 120 int required_opts; 121 int allowed_opts; 122 struct nvme_ctrl *(*create_ctrl)(struct device *dev, 123 struct nvmf_ctrl_options *opts); 124 }; 125 126 int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val); 127 int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val); 128 int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val); 129 int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl); 130 int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid); 131 int nvmf_register_transport(struct nvmf_transport_ops *ops); 132 void nvmf_unregister_transport(struct nvmf_transport_ops *ops); 133 void nvmf_free_options(struct nvmf_ctrl_options *opts); 134 const char *nvmf_get_subsysnqn(struct nvme_ctrl *ctrl); 135 int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size); 136 137 #endif /* _NVME_FABRICS_H */ 138