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 * Define a host as seen by the target. We allocate one at boot, but also
23 * allow the override it when creating controllers. This is both to provide
24 * persistence of the Host NQN over multiple boots, and to allow using
25 * multiple ones, for example in a container scenario. Because we must not
26 * use different Host NQNs with the same Host ID we generate a Host ID and
27 * use this structure to keep track of the relation between the two.
28 */
29 struct nvmf_host {
30 struct kref ref;
31 struct list_head list;
32 char nqn[NVMF_NQN_SIZE];
33 uuid_t id;
34 };
35
36 /**
37 * enum nvmf_parsing_opts - used to define the sysfs parsing options used.
38 */
39 enum {
40 NVMF_OPT_ERR = 0,
41 NVMF_OPT_TRANSPORT = 1 << 0,
42 NVMF_OPT_NQN = 1 << 1,
43 NVMF_OPT_TRADDR = 1 << 2,
44 NVMF_OPT_TRSVCID = 1 << 3,
45 NVMF_OPT_QUEUE_SIZE = 1 << 4,
46 NVMF_OPT_NR_IO_QUEUES = 1 << 5,
47 NVMF_OPT_TL_RETRY_COUNT = 1 << 6,
48 NVMF_OPT_KATO = 1 << 7,
49 NVMF_OPT_HOSTNQN = 1 << 8,
50 NVMF_OPT_RECONNECT_DELAY = 1 << 9,
51 NVMF_OPT_HOST_TRADDR = 1 << 10,
52 NVMF_OPT_CTRL_LOSS_TMO = 1 << 11,
53 NVMF_OPT_HOST_ID = 1 << 12,
54 NVMF_OPT_DUP_CONNECT = 1 << 13,
55 NVMF_OPT_DISABLE_SQFLOW = 1 << 14,
56 NVMF_OPT_HDR_DIGEST = 1 << 15,
57 NVMF_OPT_DATA_DIGEST = 1 << 16,
58 NVMF_OPT_NR_WRITE_QUEUES = 1 << 17,
59 NVMF_OPT_NR_POLL_QUEUES = 1 << 18,
60 NVMF_OPT_TOS = 1 << 19,
61 NVMF_OPT_FAIL_FAST_TMO = 1 << 20,
62 NVMF_OPT_HOST_IFACE = 1 << 21,
63 NVMF_OPT_DISCOVERY = 1 << 22,
64 NVMF_OPT_DHCHAP_SECRET = 1 << 23,
65 NVMF_OPT_DHCHAP_CTRL_SECRET = 1 << 24,
66 NVMF_OPT_TLS = 1 << 25,
67 NVMF_OPT_KEYRING = 1 << 26,
68 NVMF_OPT_TLS_KEY = 1 << 27,
69 };
70
71 /**
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 * @max_reconnects: maximum number of allowed reconnect attempts before removing
77 * the controller, (-1) means reconnect forever, zero means remove
78 * immediately;
79 * @transport: Holds the fabric transport "technology name" (for a lack of
80 * better description) that will be used by an NVMe controller
81 * being added.
82 * @subsysnqn: Hold the fully qualified NQN subystem name (format defined
83 * in the NVMe specification, "NVMe Qualified Names").
84 * @traddr: The transport-specific TRADDR field for a port on the
85 * subsystem which is adding a controller.
86 * @trsvcid: The transport-specific TRSVCID field for a port on the
87 * subsystem which is adding a controller.
88 * @host_traddr: A transport-specific field identifying the NVME host port
89 * to use for the connection to the controller.
90 * @host_iface: A transport-specific field identifying the NVME host
91 * interface to use for the connection to the controller.
92 * @queue_size: Number of IO queue elements.
93 * @nr_io_queues: Number of controller IO queues that will be established.
94 * @reconnect_delay: Time between two consecutive reconnect attempts.
95 * @discovery_nqn: indicates if the subsysnqn is the well-known discovery NQN.
96 * @kato: Keep-alive timeout.
97 * @host: Virtual NVMe host, contains the NQN and Host ID.
98 * @dhchap_secret: DH-HMAC-CHAP secret
99 * @dhchap_ctrl_secret: DH-HMAC-CHAP controller secret for bi-directional
100 * authentication
101 * @keyring: Keyring to use for key lookups
102 * @tls_key: TLS key for encrypted connections (TCP)
103 * @tls: Start TLS encrypted connections (TCP)
104 * @disable_sqflow: disable controller sq flow control
105 * @hdr_digest: generate/verify header digest (TCP)
106 * @data_digest: generate/verify data digest (TCP)
107 * @nr_write_queues: number of queues for write I/O
108 * @nr_poll_queues: number of queues for polling I/O
109 * @tos: type of service
110 * @fast_io_fail_tmo: Fast I/O fail timeout in seconds
111 */
112 struct nvmf_ctrl_options {
113 unsigned mask;
114 int max_reconnects;
115 char *transport;
116 char *subsysnqn;
117 char *traddr;
118 char *trsvcid;
119 char *host_traddr;
120 char *host_iface;
121 size_t queue_size;
122 unsigned int nr_io_queues;
123 unsigned int reconnect_delay;
124 bool discovery_nqn;
125 bool duplicate_connect;
126 unsigned int kato;
127 struct nvmf_host *host;
128 char *dhchap_secret;
129 char *dhchap_ctrl_secret;
130 struct key *keyring;
131 struct key *tls_key;
132 bool tls;
133 bool disable_sqflow;
134 bool hdr_digest;
135 bool data_digest;
136 unsigned int nr_write_queues;
137 unsigned int nr_poll_queues;
138 int tos;
139 int fast_io_fail_tmo;
140 };
141
142 /*
143 * struct nvmf_transport_ops - used to register a specific
144 * fabric implementation of NVMe fabrics.
145 * @entry: Used by the fabrics library to add the new
146 * registration entry to its linked-list internal tree.
147 * @module: Transport module reference
148 * @name: Name of the NVMe fabric driver implementation.
149 * @required_opts: sysfs command-line options that must be specified
150 * when adding a new NVMe controller.
151 * @allowed_opts: sysfs command-line options that can be specified
152 * when adding a new NVMe controller.
153 * @create_ctrl(): function pointer that points to a non-NVMe
154 * implementation-specific fabric technology
155 * that would go into starting up that fabric
156 * for the purpose of conneciton to an NVMe controller
157 * using that fabric technology.
158 *
159 * Notes:
160 * 1. At minimum, 'required_opts' and 'allowed_opts' should
161 * be set to the same enum parsing options defined earlier.
162 * 2. create_ctrl() must be defined (even if it does nothing)
163 * 3. struct nvmf_transport_ops must be statically allocated in the
164 * modules .bss section so that a pure module_get on @module
165 * prevents the memory from beeing freed.
166 */
167 struct nvmf_transport_ops {
168 struct list_head entry;
169 struct module *module;
170 const char *name;
171 int required_opts;
172 int allowed_opts;
173 struct nvme_ctrl *(*create_ctrl)(struct device *dev,
174 struct nvmf_ctrl_options *opts);
175 };
176
177 static inline bool
nvmf_ctlr_matches_baseopts(struct nvme_ctrl * ctrl,struct nvmf_ctrl_options * opts)178 nvmf_ctlr_matches_baseopts(struct nvme_ctrl *ctrl,
179 struct nvmf_ctrl_options *opts)
180 {
181 enum nvme_ctrl_state state = nvme_ctrl_state(ctrl);
182
183 if (state == NVME_CTRL_DELETING ||
184 state == NVME_CTRL_DELETING_NOIO ||
185 state == NVME_CTRL_DEAD ||
186 strcmp(opts->subsysnqn, ctrl->opts->subsysnqn) ||
187 strcmp(opts->host->nqn, ctrl->opts->host->nqn) ||
188 !uuid_equal(&opts->host->id, &ctrl->opts->host->id))
189 return false;
190
191 return true;
192 }
193
nvmf_ctrl_subsysnqn(struct nvme_ctrl * ctrl)194 static inline char *nvmf_ctrl_subsysnqn(struct nvme_ctrl *ctrl)
195 {
196 if (!ctrl->subsys ||
197 !strcmp(ctrl->opts->subsysnqn, NVME_DISC_SUBSYS_NAME))
198 return ctrl->opts->subsysnqn;
199 return ctrl->subsys->subnqn;
200 }
201
nvmf_complete_timed_out_request(struct request * rq)202 static inline void nvmf_complete_timed_out_request(struct request *rq)
203 {
204 if (blk_mq_request_started(rq) && !blk_mq_request_completed(rq)) {
205 nvme_req(rq)->status = NVME_SC_HOST_ABORTED_CMD;
206 blk_mq_complete_request(rq);
207 }
208 }
209
nvmf_nr_io_queues(struct nvmf_ctrl_options * opts)210 static inline unsigned int nvmf_nr_io_queues(struct nvmf_ctrl_options *opts)
211 {
212 return min(opts->nr_io_queues, num_online_cpus()) +
213 min(opts->nr_write_queues, num_online_cpus()) +
214 min(opts->nr_poll_queues, num_online_cpus());
215 }
216
217 int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val);
218 int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val);
219 int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val);
220 int nvmf_subsystem_reset(struct nvme_ctrl *ctrl);
221 int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl);
222 int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid);
223 int nvmf_register_transport(struct nvmf_transport_ops *ops);
224 void nvmf_unregister_transport(struct nvmf_transport_ops *ops);
225 void nvmf_free_options(struct nvmf_ctrl_options *opts);
226 int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size);
227 bool nvmf_should_reconnect(struct nvme_ctrl *ctrl, int status);
228 bool nvmf_ip_options_match(struct nvme_ctrl *ctrl,
229 struct nvmf_ctrl_options *opts);
230 void nvmf_set_io_queues(struct nvmf_ctrl_options *opts, u32 nr_io_queues,
231 u32 io_queues[HCTX_MAX_TYPES]);
232 void nvmf_map_queues(struct blk_mq_tag_set *set, struct nvme_ctrl *ctrl,
233 u32 io_queues[HCTX_MAX_TYPES]);
234
235 #endif /* _NVME_FABRICS_H */
236