1 /* SPDX-License-Identifier: GPL-2.0 */
3 * NVMe over Fabrics common host code.
4 * Copyright (c) 2015-2016 HGST, a Western Digital Company.
6 #ifndef _NVME_FABRICS_H
7 #define _NVME_FABRICS_H 1
10 #include <linux/inet.h>
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
22 * Reserved one command for internal usage. This command is used for sending
23 * the connect command, as well as for the keep alive command on the admin
26 #define NVMF_RESERVED_TAGS 1
29 * Define a host as seen by the target. We allocate one at boot, but also
30 * allow the override it when creating controllers. This is both to provide
31 * persistence of the Host NQN over multiple boots, and to allow using
32 * multiple ones, for example in a container scenario. Because we must not
33 * use different Host NQNs with the same Host ID we generate a Host ID and
34 * use this structure to keep track of the relation between the two.
38 struct list_head list;
39 char nqn[NVMF_NQN_SIZE];
44 * enum nvmf_parsing_opts - used to define the sysfs parsing options used.
48 NVMF_OPT_TRANSPORT = 1 << 0,
49 NVMF_OPT_NQN = 1 << 1,
50 NVMF_OPT_TRADDR = 1 << 2,
51 NVMF_OPT_TRSVCID = 1 << 3,
52 NVMF_OPT_QUEUE_SIZE = 1 << 4,
53 NVMF_OPT_NR_IO_QUEUES = 1 << 5,
54 NVMF_OPT_TL_RETRY_COUNT = 1 << 6,
55 NVMF_OPT_KATO = 1 << 7,
56 NVMF_OPT_HOSTNQN = 1 << 8,
57 NVMF_OPT_RECONNECT_DELAY = 1 << 9,
58 NVMF_OPT_HOST_TRADDR = 1 << 10,
59 NVMF_OPT_CTRL_LOSS_TMO = 1 << 11,
60 NVMF_OPT_HOST_ID = 1 << 12,
61 NVMF_OPT_DUP_CONNECT = 1 << 13,
62 NVMF_OPT_DISABLE_SQFLOW = 1 << 14,
63 NVMF_OPT_HDR_DIGEST = 1 << 15,
64 NVMF_OPT_DATA_DIGEST = 1 << 16,
65 NVMF_OPT_NR_WRITE_QUEUES = 1 << 17,
66 NVMF_OPT_NR_POLL_QUEUES = 1 << 18,
67 NVMF_OPT_TOS = 1 << 19,
68 NVMF_OPT_FAIL_FAST_TMO = 1 << 20,
72 * struct nvmf_ctrl_options - Used to hold the options specified
73 * with the parsing opts enum.
74 * @mask: Used by the fabrics library to parse through sysfs options
75 * on adding a NVMe controller.
76 * @transport: Holds the fabric transport "technology name" (for a lack of
77 * better description) that will be used by an NVMe controller
79 * @subsysnqn: Hold the fully qualified NQN subystem name (format defined
80 * in the NVMe specification, "NVMe Qualified Names").
81 * @traddr: The transport-specific TRADDR field for a port on the
82 * subsystem which is adding a controller.
83 * @trsvcid: The transport-specific TRSVCID field for a port on the
84 * subsystem which is adding a controller.
85 * @host_traddr: A transport-specific field identifying the NVME host port
86 * to use for the connection to the controller.
87 * @queue_size: Number of IO queue elements.
88 * @nr_io_queues: Number of controller IO queues that will be established.
89 * @reconnect_delay: Time between two consecutive reconnect attempts.
90 * @discovery_nqn: indicates if the subsysnqn is the well-known discovery NQN.
91 * @kato: Keep-alive timeout.
92 * @host: Virtual NVMe host, contains the NQN and Host ID.
93 * @max_reconnects: maximum number of allowed reconnect attempts before removing
94 * the controller, (-1) means reconnect forever, zero means remove
96 * @disable_sqflow: disable controller sq flow control
97 * @hdr_digest: generate/verify header digest (TCP)
98 * @data_digest: generate/verify data digest (TCP)
99 * @nr_write_queues: number of queues for write I/O
100 * @nr_poll_queues: number of queues for polling I/O
101 * @tos: type of service
102 * @fast_io_fail_tmo: Fast I/O fail timeout in seconds
104 struct nvmf_ctrl_options {
112 unsigned int nr_io_queues;
113 unsigned int reconnect_delay;
115 bool duplicate_connect;
117 struct nvmf_host *host;
122 unsigned int nr_write_queues;
123 unsigned int nr_poll_queues;
125 int fast_io_fail_tmo;
129 * struct nvmf_transport_ops - used to register a specific
130 * fabric implementation of NVMe fabrics.
131 * @entry: Used by the fabrics library to add the new
132 * registration entry to its linked-list internal tree.
133 * @module: Transport module reference
134 * @name: Name of the NVMe fabric driver implementation.
135 * @required_opts: sysfs command-line options that must be specified
136 * when adding a new NVMe controller.
137 * @allowed_opts: sysfs command-line options that can be specified
138 * when adding a new NVMe controller.
139 * @create_ctrl(): function pointer that points to a non-NVMe
140 * implementation-specific fabric technology
141 * that would go into starting up that fabric
142 * for the purpose of conneciton to an NVMe controller
143 * using that fabric technology.
146 * 1. At minimum, 'required_opts' and 'allowed_opts' should
147 * be set to the same enum parsing options defined earlier.
148 * 2. create_ctrl() must be defined (even if it does nothing)
149 * 3. struct nvmf_transport_ops must be statically allocated in the
150 * modules .bss section so that a pure module_get on @module
151 * prevents the memory from beeing freed.
153 struct nvmf_transport_ops {
154 struct list_head entry;
155 struct module *module;
159 struct nvme_ctrl *(*create_ctrl)(struct device *dev,
160 struct nvmf_ctrl_options *opts);
164 nvmf_ctlr_matches_baseopts(struct nvme_ctrl *ctrl,
165 struct nvmf_ctrl_options *opts)
167 if (ctrl->state == NVME_CTRL_DELETING ||
168 ctrl->state == NVME_CTRL_DEAD ||
169 strcmp(opts->subsysnqn, ctrl->opts->subsysnqn) ||
170 strcmp(opts->host->nqn, ctrl->opts->host->nqn) ||
171 memcmp(&opts->host->id, &ctrl->opts->host->id, sizeof(uuid_t)))
177 int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val);
178 int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val);
179 int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val);
180 int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl);
181 int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid, bool poll);
182 int nvmf_register_transport(struct nvmf_transport_ops *ops);
183 void nvmf_unregister_transport(struct nvmf_transport_ops *ops);
184 void nvmf_free_options(struct nvmf_ctrl_options *opts);
185 int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size);
186 bool nvmf_should_reconnect(struct nvme_ctrl *ctrl);
187 blk_status_t nvmf_fail_nonready_command(struct nvme_ctrl *ctrl,
189 bool __nvmf_check_ready(struct nvme_ctrl *ctrl, struct request *rq,
191 bool nvmf_ip_options_match(struct nvme_ctrl *ctrl,
192 struct nvmf_ctrl_options *opts);
194 static inline bool nvmf_check_ready(struct nvme_ctrl *ctrl, struct request *rq,
197 if (likely(ctrl->state == NVME_CTRL_LIVE ||
198 ctrl->state == NVME_CTRL_DELETING))
200 return __nvmf_check_ready(ctrl, rq, queue_live);
203 #endif /* _NVME_FABRICS_H */