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