summaryrefslogtreecommitdiff
path: root/drivers/nvme/host/fabrics.h
blob: 21d75dc4a3a09126e4a58ed0f9e3fefae692053d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
/* SPDX-License-Identifier: GPL-2.0 */
/*
 * NVMe over Fabrics common host code.
 * Copyright (c) 2015-2016 HGST, a Western Digital Company.
 */
#ifndef _NVME_FABRICS_H
#define _NVME_FABRICS_H 1

#include <linux/in.h>
#include <linux/inet.h>

#define NVMF_MIN_QUEUE_SIZE	16
#define NVMF_MAX_QUEUE_SIZE	1024
#define NVMF_DEF_QUEUE_SIZE	128
#define NVMF_DEF_RECONNECT_DELAY	10
/* default to 600 seconds of reconnect attempts before giving up */
#define NVMF_DEF_CTRL_LOSS_TMO		600
/* default is -1: the fail fast mechanism is disabled  */
#define NVMF_DEF_FAIL_FAST_TMO		-1

/*
 * Define a host as seen by the target.  We allocate one at boot, but also
 * allow the override it when creating controllers.  This is both to provide
 * persistence of the Host NQN over multiple boots, and to allow using
 * multiple ones, for example in a container scenario.  Because we must not
 * use different Host NQNs with the same Host ID we generate a Host ID and
 * use this structure to keep track of the relation between the two.
 */
struct nvmf_host {
	struct kref		ref;
	struct list_head	list;
	char			nqn[NVMF_NQN_SIZE];
	uuid_t			id;
};

/**
 * enum nvmf_parsing_opts - used to define the sysfs parsing options used.
 */
enum {
	NVMF_OPT_ERR		= 0,
	NVMF_OPT_TRANSPORT	= 1 << 0,
	NVMF_OPT_NQN		= 1 << 1,
	NVMF_OPT_TRADDR		= 1 << 2,
	NVMF_OPT_TRSVCID	= 1 << 3,
	NVMF_OPT_QUEUE_SIZE	= 1 << 4,
	NVMF_OPT_NR_IO_QUEUES	= 1 << 5,
	NVMF_OPT_TL_RETRY_COUNT	= 1 << 6,
	NVMF_OPT_KATO		= 1 << 7,
	NVMF_OPT_HOSTNQN	= 1 << 8,
	NVMF_OPT_RECONNECT_DELAY = 1 << 9,
	NVMF_OPT_HOST_TRADDR	= 1 << 10,
	NVMF_OPT_CTRL_LOSS_TMO	= 1 << 11,
	NVMF_OPT_HOST_ID	= 1 << 12,
	NVMF_OPT_DUP_CONNECT	= 1 << 13,
	NVMF_OPT_DISABLE_SQFLOW = 1 << 14,
	NVMF_OPT_HDR_DIGEST	= 1 << 15,
	NVMF_OPT_DATA_DIGEST	= 1 << 16,
	NVMF_OPT_NR_WRITE_QUEUES = 1 << 17,
	NVMF_OPT_NR_POLL_QUEUES = 1 << 18,
	NVMF_OPT_TOS		= 1 << 19,
	NVMF_OPT_FAIL_FAST_TMO	= 1 << 20,
	NVMF_OPT_HOST_IFACE	= 1 << 21,
	NVMF_OPT_DISCOVERY	= 1 << 22,
	NVMF_OPT_DHCHAP_SECRET	= 1 << 23,
	NVMF_OPT_DHCHAP_CTRL_SECRET = 1 << 24,
	NVMF_OPT_TLS		= 1 << 25,
	NVMF_OPT_KEYRING	= 1 << 26,
	NVMF_OPT_TLS_KEY	= 1 << 27,
};

/**
 * struct nvmf_ctrl_options - Used to hold the options specified
 *			      with the parsing opts enum.
 * @mask:	Used by the fabrics library to parse through sysfs options
 *		on adding a NVMe controller.
 * @max_reconnects: maximum number of allowed reconnect attempts before removing
 *		the controller, (-1) means reconnect forever, zero means remove
 *		immediately;
 * @transport:	Holds the fabric transport "technology name" (for a lack of
 *		better description) that will be used by an NVMe controller
 *		being added.
 * @subsysnqn:	Hold the fully qualified NQN subystem name (format defined
 *		in the NVMe specification, "NVMe Qualified Names").
 * @traddr:	The transport-specific TRADDR field for a port on the
 *              subsystem which is adding a controller.
 * @trsvcid:	The transport-specific TRSVCID field for a port on the
 *              subsystem which is adding a controller.
 * @host_traddr: A transport-specific field identifying the NVME host port
 *     to use for the connection to the controller.
 * @host_iface: A transport-specific field identifying the NVME host
 *     interface to use for the connection to the controller.
 * @queue_size: Number of IO queue elements.
 * @nr_io_queues: Number of controller IO queues that will be established.
 * @reconnect_delay: Time between two consecutive reconnect attempts.
 * @discovery_nqn: indicates if the subsysnqn is the well-known discovery NQN.
 * @kato:	Keep-alive timeout.
 * @host:	Virtual NVMe host, contains the NQN and Host ID.
 * @dhchap_secret: DH-HMAC-CHAP secret
 * @dhchap_ctrl_secret: DH-HMAC-CHAP controller secret for bi-directional
 *              authentication
 * @keyring:    Keyring to use for key lookups
 * @tls_key:    TLS key for encrypted connections (TCP)
 * @tls:        Start TLS encrypted connections (TCP)
 * @disable_sqflow: disable controller sq flow control
 * @hdr_digest: generate/verify header digest (TCP)
 * @data_digest: generate/verify data digest (TCP)
 * @nr_write_queues: number of queues for write I/O
 * @nr_poll_queues: number of queues for polling I/O
 * @tos: type of service
 * @fast_io_fail_tmo: Fast I/O fail timeout in seconds
 */
struct nvmf_ctrl_options {
	unsigned		mask;
	int			max_reconnects;
	char			*transport;
	char			*subsysnqn;
	char			*traddr;
	char			*trsvcid;
	char			*host_traddr;
	char			*host_iface;
	size_t			queue_size;
	unsigned int		nr_io_queues;
	unsigned int		reconnect_delay;
	bool			discovery_nqn;
	bool			duplicate_connect;
	unsigned int		kato;
	struct nvmf_host	*host;
	char			*dhchap_secret;
	char			*dhchap_ctrl_secret;
	struct key		*keyring;
	struct key		*tls_key;
	bool			tls;
	bool			disable_sqflow;
	bool			hdr_digest;
	bool			data_digest;
	unsigned int		nr_write_queues;
	unsigned int		nr_poll_queues;
	int			tos;
	int			fast_io_fail_tmo;
};

/*
 * struct nvmf_transport_ops - used to register a specific
 *			       fabric implementation of NVMe fabrics.
 * @entry:		Used by the fabrics library to add the new
 *			registration entry to its linked-list internal tree.
 * @module:             Transport module reference
 * @name:		Name of the NVMe fabric driver implementation.
 * @required_opts:	sysfs command-line options that must be specified
 *			when adding a new NVMe controller.
 * @allowed_opts:	sysfs command-line options that can be specified
 *			when adding a new NVMe controller.
 * @create_ctrl():	function pointer that points to a non-NVMe
 *			implementation-specific fabric technology
 *			that would go into starting up that fabric
 *			for the purpose of conneciton to an NVMe controller
 *			using that fabric technology.
 *
 * Notes:
 *	1. At minimum, 'required_opts' and 'allowed_opts' should
 *	   be set to the same enum parsing options defined earlier.
 *	2. create_ctrl() must be defined (even if it does nothing)
 *	3. struct nvmf_transport_ops must be statically allocated in the
 *	   modules .bss section so that a pure module_get on @module
 *	   prevents the memory from beeing freed.
 */
struct nvmf_transport_ops {
	struct list_head	entry;
	struct module		*module;
	const char		*name;
	int			required_opts;
	int			allowed_opts;
	struct nvme_ctrl	*(*create_ctrl)(struct device *dev,
					struct nvmf_ctrl_options *opts);
};

static inline bool
nvmf_ctlr_matches_baseopts(struct nvme_ctrl *ctrl,
			struct nvmf_ctrl_options *opts)
{
	enum nvme_ctrl_state state = nvme_ctrl_state(ctrl);

	if (state == NVME_CTRL_DELETING ||
	    state == NVME_CTRL_DELETING_NOIO ||
	    state == NVME_CTRL_DEAD ||
	    strcmp(opts->subsysnqn, ctrl->opts->subsysnqn) ||
	    strcmp(opts->host->nqn, ctrl->opts->host->nqn) ||
	    !uuid_equal(&opts->host->id, &ctrl->opts->host->id))
		return false;

	return true;
}

static inline char *nvmf_ctrl_subsysnqn(struct nvme_ctrl *ctrl)
{
	if (!ctrl->subsys ||
	    !strcmp(ctrl->opts->subsysnqn, NVME_DISC_SUBSYS_NAME))
		return ctrl->opts->subsysnqn;
	return ctrl->subsys->subnqn;
}

static inline void nvmf_complete_timed_out_request(struct request *rq)
{
	if (blk_mq_request_started(rq) && !blk_mq_request_completed(rq)) {
		nvme_req(rq)->status = NVME_SC_HOST_ABORTED_CMD;
		blk_mq_complete_request(rq);
	}
}

static inline unsigned int nvmf_nr_io_queues(struct nvmf_ctrl_options *opts)
{
	return min(opts->nr_io_queues, num_online_cpus()) +
		min(opts->nr_write_queues, num_online_cpus()) +
		min(opts->nr_poll_queues, num_online_cpus());
}

int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val);
int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val);
int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val);
int nvmf_subsystem_reset(struct nvme_ctrl *ctrl);
int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl);
int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid);
int nvmf_register_transport(struct nvmf_transport_ops *ops);
void nvmf_unregister_transport(struct nvmf_transport_ops *ops);
void nvmf_free_options(struct nvmf_ctrl_options *opts);
int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size);
bool nvmf_should_reconnect(struct nvme_ctrl *ctrl, int status);
bool nvmf_ip_options_match(struct nvme_ctrl *ctrl,
		struct nvmf_ctrl_options *opts);
void nvmf_set_io_queues(struct nvmf_ctrl_options *opts, u32 nr_io_queues,
			u32 io_queues[HCTX_MAX_TYPES]);
void nvmf_map_queues(struct blk_mq_tag_set *set, struct nvme_ctrl *ctrl,
		     u32 io_queues[HCTX_MAX_TYPES]);

#endif /* _NVME_FABRICS_H */