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/* default is -1: the fail fast mechanism is disabled */
19#define NVMF_DEF_FAIL_FAST_TMO -1
20
21/*
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
24 * queue once live.
25 */
26#define NVMF_RESERVED_TAGS 1
27
28/*
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.
35 */
36struct nvmf_host {
37 struct kref ref;
38 struct list_head list;
39 char nqn[NVMF_NQN_SIZE];
40 uuid_t id;
41};
42
43/**
44 * enum nvmf_parsing_opts - used to define the sysfs parsing options used.
45 */
46enum {
47 NVMF_OPT_ERR = 0,
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,
69 NVMF_OPT_HOST_IFACE = 1 << 21,
70 NVMF_OPT_DISCOVERY = 1 << 22,
71 NVMF_OPT_DHCHAP_SECRET = 1 << 23,
72 NVMF_OPT_DHCHAP_CTRL_SECRET = 1 << 24,
73 NVMF_OPT_TLS = 1 << 25,
74 NVMF_OPT_KEYRING = 1 << 26,
75 NVMF_OPT_TLS_KEY = 1 << 27,
76};
77
78/**
79 * struct nvmf_ctrl_options - Used to hold the options specified
80 * with the parsing opts enum.
81 * @mask: Used by the fabrics library to parse through sysfs options
82 * on adding a NVMe controller.
83 * @max_reconnects: maximum number of allowed reconnect attempts before removing
84 * the controller, (-1) means reconnect forever, zero means remove
85 * immediately;
86 * @transport: Holds the fabric transport "technology name" (for a lack of
87 * better description) that will be used by an NVMe controller
88 * being added.
89 * @subsysnqn: Hold the fully qualified NQN subystem name (format defined
90 * in the NVMe specification, "NVMe Qualified Names").
91 * @traddr: The transport-specific TRADDR field for a port on the
92 * subsystem which is adding a controller.
93 * @trsvcid: The transport-specific TRSVCID field for a port on the
94 * subsystem which is adding a controller.
95 * @host_traddr: A transport-specific field identifying the NVME host port
96 * to use for the connection to the controller.
97 * @host_iface: A transport-specific field identifying the NVME host
98 * interface to use for the connection to the controller.
99 * @queue_size: Number of IO queue elements.
100 * @nr_io_queues: Number of controller IO queues that will be established.
101 * @reconnect_delay: Time between two consecutive reconnect attempts.
102 * @discovery_nqn: indicates if the subsysnqn is the well-known discovery NQN.
103 * @kato: Keep-alive timeout.
104 * @host: Virtual NVMe host, contains the NQN and Host ID.
105 * @dhchap_secret: DH-HMAC-CHAP secret
106 * @dhchap_ctrl_secret: DH-HMAC-CHAP controller secret for bi-directional
107 * authentication
108 * @keyring: Keyring to use for key lookups
109 * @tls_key: TLS key for encrypted connections (TCP)
110 * @tls: Start TLS encrypted connections (TCP)
111 * @disable_sqflow: disable controller sq flow control
112 * @hdr_digest: generate/verify header digest (TCP)
113 * @data_digest: generate/verify data digest (TCP)
114 * @nr_write_queues: number of queues for write I/O
115 * @nr_poll_queues: number of queues for polling I/O
116 * @tos: type of service
117 * @fast_io_fail_tmo: Fast I/O fail timeout in seconds
118 */
119struct nvmf_ctrl_options {
120 unsigned mask;
121 int max_reconnects;
122 char *transport;
123 char *subsysnqn;
124 char *traddr;
125 char *trsvcid;
126 char *host_traddr;
127 char *host_iface;
128 size_t queue_size;
129 unsigned int nr_io_queues;
130 unsigned int reconnect_delay;
131 bool discovery_nqn;
132 bool duplicate_connect;
133 unsigned int kato;
134 struct nvmf_host *host;
135 char *dhchap_secret;
136 char *dhchap_ctrl_secret;
137 struct key *keyring;
138 struct key *tls_key;
139 bool tls;
140 bool disable_sqflow;
141 bool hdr_digest;
142 bool data_digest;
143 unsigned int nr_write_queues;
144 unsigned int nr_poll_queues;
145 int tos;
146 int fast_io_fail_tmo;
147};
148
149/*
150 * struct nvmf_transport_ops - used to register a specific
151 * fabric implementation of NVMe fabrics.
152 * @entry: Used by the fabrics library to add the new
153 * registration entry to its linked-list internal tree.
154 * @module: Transport module reference
155 * @name: Name of the NVMe fabric driver implementation.
156 * @required_opts: sysfs command-line options that must be specified
157 * when adding a new NVMe controller.
158 * @allowed_opts: sysfs command-line options that can be specified
159 * when adding a new NVMe controller.
160 * @create_ctrl(): function pointer that points to a non-NVMe
161 * implementation-specific fabric technology
162 * that would go into starting up that fabric
163 * for the purpose of conneciton to an NVMe controller
164 * using that fabric technology.
165 *
166 * Notes:
167 * 1. At minimum, 'required_opts' and 'allowed_opts' should
168 * be set to the same enum parsing options defined earlier.
169 * 2. create_ctrl() must be defined (even if it does nothing)
170 * 3. struct nvmf_transport_ops must be statically allocated in the
171 * modules .bss section so that a pure module_get on @module
172 * prevents the memory from beeing freed.
173 */
174struct nvmf_transport_ops {
175 struct list_head entry;
176 struct module *module;
177 const char *name;
178 int required_opts;
179 int allowed_opts;
180 struct nvme_ctrl *(*create_ctrl)(struct device *dev,
181 struct nvmf_ctrl_options *opts);
182};
183
184static inline bool
185nvmf_ctlr_matches_baseopts(struct nvme_ctrl *ctrl,
186 struct nvmf_ctrl_options *opts)
187{
188 if (ctrl->state == NVME_CTRL_DELETING ||
189 ctrl->state == NVME_CTRL_DELETING_NOIO ||
190 ctrl->state == NVME_CTRL_DEAD ||
191 strcmp(opts->subsysnqn, ctrl->opts->subsysnqn) ||
192 strcmp(opts->host->nqn, ctrl->opts->host->nqn) ||
193 !uuid_equal(u1: &opts->host->id, u2: &ctrl->opts->host->id))
194 return false;
195
196 return true;
197}
198
199static inline char *nvmf_ctrl_subsysnqn(struct nvme_ctrl *ctrl)
200{
201 if (!ctrl->subsys ||
202 !strcmp(ctrl->opts->subsysnqn, NVME_DISC_SUBSYS_NAME))
203 return ctrl->opts->subsysnqn;
204 return ctrl->subsys->subnqn;
205}
206
207static inline void nvmf_complete_timed_out_request(struct request *rq)
208{
209 if (blk_mq_request_started(rq) && !blk_mq_request_completed(rq)) {
210 nvme_req(req: rq)->status = NVME_SC_HOST_ABORTED_CMD;
211 blk_mq_complete_request(rq);
212 }
213}
214
215static inline unsigned int nvmf_nr_io_queues(struct nvmf_ctrl_options *opts)
216{
217 return min(opts->nr_io_queues, num_online_cpus()) +
218 min(opts->nr_write_queues, num_online_cpus()) +
219 min(opts->nr_poll_queues, num_online_cpus());
220}
221
222int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val);
223int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val);
224int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val);
225int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl);
226int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid);
227int nvmf_register_transport(struct nvmf_transport_ops *ops);
228void nvmf_unregister_transport(struct nvmf_transport_ops *ops);
229void nvmf_free_options(struct nvmf_ctrl_options *opts);
230int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size);
231bool nvmf_should_reconnect(struct nvme_ctrl *ctrl);
232bool nvmf_ip_options_match(struct nvme_ctrl *ctrl,
233 struct nvmf_ctrl_options *opts);
234void nvmf_set_io_queues(struct nvmf_ctrl_options *opts, u32 nr_io_queues,
235 u32 io_queues[HCTX_MAX_TYPES]);
236void nvmf_map_queues(struct blk_mq_tag_set *set, struct nvme_ctrl *ctrl,
237 u32 io_queues[HCTX_MAX_TYPES]);
238
239#endif /* _NVME_FABRICS_H */
240

source code of linux/drivers/nvme/host/fabrics.h