1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * NVMe over Fabrics common host code.
4*4882a593Smuzhiyun * Copyright (c) 2015-2016 HGST, a Western Digital Company.
5*4882a593Smuzhiyun */
6*4882a593Smuzhiyun #ifndef _NVME_FABRICS_H
7*4882a593Smuzhiyun #define _NVME_FABRICS_H 1
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun #include <linux/in.h>
10*4882a593Smuzhiyun #include <linux/inet.h>
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun #define NVMF_MIN_QUEUE_SIZE 16
13*4882a593Smuzhiyun #define NVMF_MAX_QUEUE_SIZE 1024
14*4882a593Smuzhiyun #define NVMF_DEF_QUEUE_SIZE 128
15*4882a593Smuzhiyun #define NVMF_DEF_RECONNECT_DELAY 10
16*4882a593Smuzhiyun /* default to 600 seconds of reconnect attempts before giving up */
17*4882a593Smuzhiyun #define NVMF_DEF_CTRL_LOSS_TMO 600
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun /*
20*4882a593Smuzhiyun * Define a host as seen by the target. We allocate one at boot, but also
21*4882a593Smuzhiyun * allow the override it when creating controllers. This is both to provide
22*4882a593Smuzhiyun * persistence of the Host NQN over multiple boots, and to allow using
23*4882a593Smuzhiyun * multiple ones, for example in a container scenario. Because we must not
24*4882a593Smuzhiyun * use different Host NQNs with the same Host ID we generate a Host ID and
25*4882a593Smuzhiyun * use this structure to keep track of the relation between the two.
26*4882a593Smuzhiyun */
27*4882a593Smuzhiyun struct nvmf_host {
28*4882a593Smuzhiyun struct kref ref;
29*4882a593Smuzhiyun struct list_head list;
30*4882a593Smuzhiyun char nqn[NVMF_NQN_SIZE];
31*4882a593Smuzhiyun uuid_t id;
32*4882a593Smuzhiyun };
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun /**
35*4882a593Smuzhiyun * enum nvmf_parsing_opts - used to define the sysfs parsing options used.
36*4882a593Smuzhiyun */
37*4882a593Smuzhiyun enum {
38*4882a593Smuzhiyun NVMF_OPT_ERR = 0,
39*4882a593Smuzhiyun NVMF_OPT_TRANSPORT = 1 << 0,
40*4882a593Smuzhiyun NVMF_OPT_NQN = 1 << 1,
41*4882a593Smuzhiyun NVMF_OPT_TRADDR = 1 << 2,
42*4882a593Smuzhiyun NVMF_OPT_TRSVCID = 1 << 3,
43*4882a593Smuzhiyun NVMF_OPT_QUEUE_SIZE = 1 << 4,
44*4882a593Smuzhiyun NVMF_OPT_NR_IO_QUEUES = 1 << 5,
45*4882a593Smuzhiyun NVMF_OPT_TL_RETRY_COUNT = 1 << 6,
46*4882a593Smuzhiyun NVMF_OPT_KATO = 1 << 7,
47*4882a593Smuzhiyun NVMF_OPT_HOSTNQN = 1 << 8,
48*4882a593Smuzhiyun NVMF_OPT_RECONNECT_DELAY = 1 << 9,
49*4882a593Smuzhiyun NVMF_OPT_HOST_TRADDR = 1 << 10,
50*4882a593Smuzhiyun NVMF_OPT_CTRL_LOSS_TMO = 1 << 11,
51*4882a593Smuzhiyun NVMF_OPT_HOST_ID = 1 << 12,
52*4882a593Smuzhiyun NVMF_OPT_DUP_CONNECT = 1 << 13,
53*4882a593Smuzhiyun NVMF_OPT_DISABLE_SQFLOW = 1 << 14,
54*4882a593Smuzhiyun NVMF_OPT_HDR_DIGEST = 1 << 15,
55*4882a593Smuzhiyun NVMF_OPT_DATA_DIGEST = 1 << 16,
56*4882a593Smuzhiyun NVMF_OPT_NR_WRITE_QUEUES = 1 << 17,
57*4882a593Smuzhiyun NVMF_OPT_NR_POLL_QUEUES = 1 << 18,
58*4882a593Smuzhiyun NVMF_OPT_TOS = 1 << 19,
59*4882a593Smuzhiyun };
60*4882a593Smuzhiyun
61*4882a593Smuzhiyun /**
62*4882a593Smuzhiyun * struct nvmf_ctrl_options - Used to hold the options specified
63*4882a593Smuzhiyun * with the parsing opts enum.
64*4882a593Smuzhiyun * @mask: Used by the fabrics library to parse through sysfs options
65*4882a593Smuzhiyun * on adding a NVMe controller.
66*4882a593Smuzhiyun * @transport: Holds the fabric transport "technology name" (for a lack of
67*4882a593Smuzhiyun * better description) that will be used by an NVMe controller
68*4882a593Smuzhiyun * being added.
69*4882a593Smuzhiyun * @subsysnqn: Hold the fully qualified NQN subystem name (format defined
70*4882a593Smuzhiyun * in the NVMe specification, "NVMe Qualified Names").
71*4882a593Smuzhiyun * @traddr: The transport-specific TRADDR field for a port on the
72*4882a593Smuzhiyun * subsystem which is adding a controller.
73*4882a593Smuzhiyun * @trsvcid: The transport-specific TRSVCID field for a port on the
74*4882a593Smuzhiyun * subsystem which is adding a controller.
75*4882a593Smuzhiyun * @host_traddr: A transport-specific field identifying the NVME host port
76*4882a593Smuzhiyun * to use for the connection to the controller.
77*4882a593Smuzhiyun * @queue_size: Number of IO queue elements.
78*4882a593Smuzhiyun * @nr_io_queues: Number of controller IO queues that will be established.
79*4882a593Smuzhiyun * @reconnect_delay: Time between two consecutive reconnect attempts.
80*4882a593Smuzhiyun * @discovery_nqn: indicates if the subsysnqn is the well-known discovery NQN.
81*4882a593Smuzhiyun * @kato: Keep-alive timeout.
82*4882a593Smuzhiyun * @host: Virtual NVMe host, contains the NQN and Host ID.
83*4882a593Smuzhiyun * @max_reconnects: maximum number of allowed reconnect attempts before removing
84*4882a593Smuzhiyun * the controller, (-1) means reconnect forever, zero means remove
85*4882a593Smuzhiyun * immediately;
86*4882a593Smuzhiyun * @disable_sqflow: disable controller sq flow control
87*4882a593Smuzhiyun * @hdr_digest: generate/verify header digest (TCP)
88*4882a593Smuzhiyun * @data_digest: generate/verify data digest (TCP)
89*4882a593Smuzhiyun * @nr_write_queues: number of queues for write I/O
90*4882a593Smuzhiyun * @nr_poll_queues: number of queues for polling I/O
91*4882a593Smuzhiyun * @tos: type of service
92*4882a593Smuzhiyun */
93*4882a593Smuzhiyun struct nvmf_ctrl_options {
94*4882a593Smuzhiyun unsigned mask;
95*4882a593Smuzhiyun char *transport;
96*4882a593Smuzhiyun char *subsysnqn;
97*4882a593Smuzhiyun char *traddr;
98*4882a593Smuzhiyun char *trsvcid;
99*4882a593Smuzhiyun char *host_traddr;
100*4882a593Smuzhiyun size_t queue_size;
101*4882a593Smuzhiyun unsigned int nr_io_queues;
102*4882a593Smuzhiyun unsigned int reconnect_delay;
103*4882a593Smuzhiyun bool discovery_nqn;
104*4882a593Smuzhiyun bool duplicate_connect;
105*4882a593Smuzhiyun unsigned int kato;
106*4882a593Smuzhiyun struct nvmf_host *host;
107*4882a593Smuzhiyun int max_reconnects;
108*4882a593Smuzhiyun bool disable_sqflow;
109*4882a593Smuzhiyun bool hdr_digest;
110*4882a593Smuzhiyun bool data_digest;
111*4882a593Smuzhiyun unsigned int nr_write_queues;
112*4882a593Smuzhiyun unsigned int nr_poll_queues;
113*4882a593Smuzhiyun int tos;
114*4882a593Smuzhiyun };
115*4882a593Smuzhiyun
116*4882a593Smuzhiyun /*
117*4882a593Smuzhiyun * struct nvmf_transport_ops - used to register a specific
118*4882a593Smuzhiyun * fabric implementation of NVMe fabrics.
119*4882a593Smuzhiyun * @entry: Used by the fabrics library to add the new
120*4882a593Smuzhiyun * registration entry to its linked-list internal tree.
121*4882a593Smuzhiyun * @module: Transport module reference
122*4882a593Smuzhiyun * @name: Name of the NVMe fabric driver implementation.
123*4882a593Smuzhiyun * @required_opts: sysfs command-line options that must be specified
124*4882a593Smuzhiyun * when adding a new NVMe controller.
125*4882a593Smuzhiyun * @allowed_opts: sysfs command-line options that can be specified
126*4882a593Smuzhiyun * when adding a new NVMe controller.
127*4882a593Smuzhiyun * @create_ctrl(): function pointer that points to a non-NVMe
128*4882a593Smuzhiyun * implementation-specific fabric technology
129*4882a593Smuzhiyun * that would go into starting up that fabric
130*4882a593Smuzhiyun * for the purpose of conneciton to an NVMe controller
131*4882a593Smuzhiyun * using that fabric technology.
132*4882a593Smuzhiyun *
133*4882a593Smuzhiyun * Notes:
134*4882a593Smuzhiyun * 1. At minimum, 'required_opts' and 'allowed_opts' should
135*4882a593Smuzhiyun * be set to the same enum parsing options defined earlier.
136*4882a593Smuzhiyun * 2. create_ctrl() must be defined (even if it does nothing)
137*4882a593Smuzhiyun * 3. struct nvmf_transport_ops must be statically allocated in the
138*4882a593Smuzhiyun * modules .bss section so that a pure module_get on @module
139*4882a593Smuzhiyun * prevents the memory from beeing freed.
140*4882a593Smuzhiyun */
141*4882a593Smuzhiyun struct nvmf_transport_ops {
142*4882a593Smuzhiyun struct list_head entry;
143*4882a593Smuzhiyun struct module *module;
144*4882a593Smuzhiyun const char *name;
145*4882a593Smuzhiyun int required_opts;
146*4882a593Smuzhiyun int allowed_opts;
147*4882a593Smuzhiyun struct nvme_ctrl *(*create_ctrl)(struct device *dev,
148*4882a593Smuzhiyun struct nvmf_ctrl_options *opts);
149*4882a593Smuzhiyun };
150*4882a593Smuzhiyun
151*4882a593Smuzhiyun static inline bool
nvmf_ctlr_matches_baseopts(struct nvme_ctrl * ctrl,struct nvmf_ctrl_options * opts)152*4882a593Smuzhiyun nvmf_ctlr_matches_baseopts(struct nvme_ctrl *ctrl,
153*4882a593Smuzhiyun struct nvmf_ctrl_options *opts)
154*4882a593Smuzhiyun {
155*4882a593Smuzhiyun if (ctrl->state == NVME_CTRL_DELETING ||
156*4882a593Smuzhiyun ctrl->state == NVME_CTRL_DELETING_NOIO ||
157*4882a593Smuzhiyun ctrl->state == NVME_CTRL_DEAD ||
158*4882a593Smuzhiyun strcmp(opts->subsysnqn, ctrl->opts->subsysnqn) ||
159*4882a593Smuzhiyun strcmp(opts->host->nqn, ctrl->opts->host->nqn) ||
160*4882a593Smuzhiyun memcmp(&opts->host->id, &ctrl->opts->host->id, sizeof(uuid_t)))
161*4882a593Smuzhiyun return false;
162*4882a593Smuzhiyun
163*4882a593Smuzhiyun return true;
164*4882a593Smuzhiyun }
165*4882a593Smuzhiyun
166*4882a593Smuzhiyun int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val);
167*4882a593Smuzhiyun int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val);
168*4882a593Smuzhiyun int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val);
169*4882a593Smuzhiyun int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl);
170*4882a593Smuzhiyun int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid, bool poll);
171*4882a593Smuzhiyun int nvmf_register_transport(struct nvmf_transport_ops *ops);
172*4882a593Smuzhiyun void nvmf_unregister_transport(struct nvmf_transport_ops *ops);
173*4882a593Smuzhiyun void nvmf_free_options(struct nvmf_ctrl_options *opts);
174*4882a593Smuzhiyun int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size);
175*4882a593Smuzhiyun bool nvmf_should_reconnect(struct nvme_ctrl *ctrl);
176*4882a593Smuzhiyun blk_status_t nvmf_fail_nonready_command(struct nvme_ctrl *ctrl,
177*4882a593Smuzhiyun struct request *rq);
178*4882a593Smuzhiyun bool __nvmf_check_ready(struct nvme_ctrl *ctrl, struct request *rq,
179*4882a593Smuzhiyun bool queue_live);
180*4882a593Smuzhiyun bool nvmf_ip_options_match(struct nvme_ctrl *ctrl,
181*4882a593Smuzhiyun struct nvmf_ctrl_options *opts);
182*4882a593Smuzhiyun
nvmf_check_ready(struct nvme_ctrl * ctrl,struct request * rq,bool queue_live)183*4882a593Smuzhiyun static inline bool nvmf_check_ready(struct nvme_ctrl *ctrl, struct request *rq,
184*4882a593Smuzhiyun bool queue_live)
185*4882a593Smuzhiyun {
186*4882a593Smuzhiyun if (likely(ctrl->state == NVME_CTRL_LIVE ||
187*4882a593Smuzhiyun ctrl->state == NVME_CTRL_DELETING))
188*4882a593Smuzhiyun return true;
189*4882a593Smuzhiyun return __nvmf_check_ready(ctrl, rq, queue_live);
190*4882a593Smuzhiyun }
191*4882a593Smuzhiyun
192*4882a593Smuzhiyun #endif /* _NVME_FABRICS_H */
193