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 */
36 struct 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 */
46 enum {
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 };
74
75 /**
76 * struct nvmf_ctrl_options - Used to hold the options specified
77 * with the parsing opts enum.
78 * @mask: Used by the fabrics library to parse through sysfs options
79 * on adding a NVMe controller.
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 subystem 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 * @max_reconnects: maximum number of allowed reconnect attempts before removing
100 * the controller, (-1) means reconnect forever, zero means remove
101 * immediately;
102 * @dhchap_secret: DH-HMAC-CHAP secret
103 * @dhchap_ctrl_secret: DH-HMAC-CHAP controller secret for bi-directional
104 * authentication
105 * @disable_sqflow: disable controller sq flow control
106 * @hdr_digest: generate/verify header digest (TCP)
107 * @data_digest: generate/verify data digest (TCP)
108 * @nr_write_queues: number of queues for write I/O
109 * @nr_poll_queues: number of queues for polling I/O
110 * @tos: type of service
111 * @fast_io_fail_tmo: Fast I/O fail timeout in seconds
112 */
113 struct nvmf_ctrl_options {
114 unsigned mask;
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 int max_reconnects;
129 char *dhchap_secret;
130 char *dhchap_ctrl_secret;
131 bool disable_sqflow;
132 bool hdr_digest;
133 bool data_digest;
134 unsigned int nr_write_queues;
135 unsigned int nr_poll_queues;
136 int tos;
137 int fast_io_fail_tmo;
138 };
139
140 /*
141 * struct nvmf_transport_ops - used to register a specific
142 * fabric implementation of NVMe fabrics.
143 * @entry: Used by the fabrics library to add the new
144 * registration entry to its linked-list internal tree.
145 * @module: Transport module reference
146 * @name: Name of the NVMe fabric driver implementation.
147 * @required_opts: sysfs command-line options that must be specified
148 * when adding a new NVMe controller.
149 * @allowed_opts: sysfs command-line options that can be specified
150 * when adding a new NVMe controller.
151 * @create_ctrl(): function pointer that points to a non-NVMe
152 * implementation-specific fabric technology
153 * that would go into starting up that fabric
154 * for the purpose of conneciton to an NVMe controller
155 * using that fabric technology.
156 *
157 * Notes:
158 * 1. At minimum, 'required_opts' and 'allowed_opts' should
159 * be set to the same enum parsing options defined earlier.
160 * 2. create_ctrl() must be defined (even if it does nothing)
161 * 3. struct nvmf_transport_ops must be statically allocated in the
162 * modules .bss section so that a pure module_get on @module
163 * prevents the memory from beeing freed.
164 */
165 struct nvmf_transport_ops {
166 struct list_head entry;
167 struct module *module;
168 const char *name;
169 int required_opts;
170 int allowed_opts;
171 struct nvme_ctrl *(*create_ctrl)(struct device *dev,
172 struct nvmf_ctrl_options *opts);
173 };
174
175 static inline bool
nvmf_ctlr_matches_baseopts(struct nvme_ctrl * ctrl,struct nvmf_ctrl_options * opts)176 nvmf_ctlr_matches_baseopts(struct nvme_ctrl *ctrl,
177 struct nvmf_ctrl_options *opts)
178 {
179 if (ctrl->state == NVME_CTRL_DELETING ||
180 ctrl->state == NVME_CTRL_DELETING_NOIO ||
181 ctrl->state == NVME_CTRL_DEAD ||
182 strcmp(opts->subsysnqn, ctrl->opts->subsysnqn) ||
183 strcmp(opts->host->nqn, ctrl->opts->host->nqn) ||
184 memcmp(&opts->host->id, &ctrl->opts->host->id, sizeof(uuid_t)))
185 return false;
186
187 return true;
188 }
189
nvmf_ctrl_subsysnqn(struct nvme_ctrl * ctrl)190 static inline char *nvmf_ctrl_subsysnqn(struct nvme_ctrl *ctrl)
191 {
192 if (!ctrl->subsys ||
193 !strcmp(ctrl->opts->subsysnqn, NVME_DISC_SUBSYS_NAME))
194 return ctrl->opts->subsysnqn;
195 return ctrl->subsys->subnqn;
196 }
197
nvmf_complete_timed_out_request(struct request * rq)198 static inline void nvmf_complete_timed_out_request(struct request *rq)
199 {
200 if (blk_mq_request_started(rq) && !blk_mq_request_completed(rq)) {
201 nvme_req(rq)->status = NVME_SC_HOST_ABORTED_CMD;
202 blk_mq_complete_request(rq);
203 }
204 }
205
206 int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val);
207 int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val);
208 int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val);
209 int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl);
210 int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid);
211 int nvmf_register_transport(struct nvmf_transport_ops *ops);
212 void nvmf_unregister_transport(struct nvmf_transport_ops *ops);
213 void nvmf_free_options(struct nvmf_ctrl_options *opts);
214 int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size);
215 bool nvmf_should_reconnect(struct nvme_ctrl *ctrl);
216 bool nvmf_ip_options_match(struct nvme_ctrl *ctrl,
217 struct nvmf_ctrl_options *opts);
218
219 #endif /* _NVME_FABRICS_H */
220