1 /*
2 * Copyright (c) 2015-2016 HGST, a Western Digital Company.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
11 * more details.
12 */
13
14 #ifndef _NVMET_H
15 #define _NVMET_H
16
17 #include <linux/dma-mapping.h>
18 #include <linux/types.h>
19 #include <linux/device.h>
20 #include <linux/kref.h>
21 #include <linux/percpu-refcount.h>
22 #include <linux/list.h>
23 #include <linux/mutex.h>
24 #include <linux/nvme.h>
25 #include <linux/configfs.h>
26 #include <linux/rcupdate.h>
27 #include <linux/blkdev.h>
28
29 #define NVMET_ASYNC_EVENTS 4
30 #define NVMET_ERROR_LOG_SLOTS 128
31
32 /* Helper Macros when NVMe error is NVME_SC_CONNECT_INVALID_PARAM
33 * The 16 bit shift is to set IATTR bit to 1, which means offending
34 * offset starts in the data section of connect()
35 */
36 #define IPO_IATTR_CONNECT_DATA(x) \
37 (cpu_to_le32((1 << 16) | (offsetof(struct nvmf_connect_data, x))))
38 #define IPO_IATTR_CONNECT_SQE(x) \
39 (cpu_to_le32(offsetof(struct nvmf_connect_command, x)))
40
41 struct nvmet_ns {
42 struct list_head dev_link;
43 struct percpu_ref ref;
44 struct block_device *bdev;
45 u32 nsid;
46 u32 blksize_shift;
47 loff_t size;
48 u8 nguid[16];
49
50 bool enabled;
51 struct nvmet_subsys *subsys;
52 const char *device_path;
53
54 struct config_group device_group;
55 struct config_group group;
56
57 struct completion disable_done;
58 };
59
to_nvmet_ns(struct config_item * item)60 static inline struct nvmet_ns *to_nvmet_ns(struct config_item *item)
61 {
62 return container_of(to_config_group(item), struct nvmet_ns, group);
63 }
64
65 struct nvmet_cq {
66 u16 qid;
67 u16 size;
68 };
69
70 struct nvmet_sq {
71 struct nvmet_ctrl *ctrl;
72 struct percpu_ref ref;
73 u16 qid;
74 u16 size;
75 struct completion free_done;
76 struct completion confirm_done;
77 };
78
79 /**
80 * struct nvmet_port - Common structure to keep port
81 * information for the target.
82 * @entry: List head for holding a list of these elements.
83 * @disc_addr: Address information is stored in a format defined
84 * for a discovery log page entry.
85 * @group: ConfigFS group for this element's folder.
86 * @priv: Private data for the transport.
87 */
88 struct nvmet_port {
89 struct list_head entry;
90 struct nvmf_disc_rsp_page_entry disc_addr;
91 struct config_group group;
92 struct config_group subsys_group;
93 struct list_head subsystems;
94 struct config_group referrals_group;
95 struct list_head referrals;
96 void *priv;
97 bool enabled;
98 };
99
to_nvmet_port(struct config_item * item)100 static inline struct nvmet_port *to_nvmet_port(struct config_item *item)
101 {
102 return container_of(to_config_group(item), struct nvmet_port,
103 group);
104 }
105
106 struct nvmet_ctrl {
107 struct nvmet_subsys *subsys;
108 struct nvmet_cq **cqs;
109 struct nvmet_sq **sqs;
110
111 struct mutex lock;
112 u64 cap;
113 u64 serial;
114 u32 cc;
115 u32 csts;
116
117 u16 cntlid;
118 u32 kato;
119
120 struct nvmet_req *async_event_cmds[NVMET_ASYNC_EVENTS];
121 unsigned int nr_async_event_cmds;
122 struct list_head async_events;
123 struct work_struct async_event_work;
124
125 struct list_head subsys_entry;
126 struct kref ref;
127 struct delayed_work ka_work;
128 struct work_struct fatal_err_work;
129
130 struct nvmet_fabrics_ops *ops;
131
132 char subsysnqn[NVMF_NQN_FIELD_LEN];
133 char hostnqn[NVMF_NQN_FIELD_LEN];
134 };
135
136 struct nvmet_subsys {
137 enum nvme_subsys_type type;
138
139 struct mutex lock;
140 struct kref ref;
141
142 struct list_head namespaces;
143 unsigned int max_nsid;
144
145 struct list_head ctrls;
146 struct ida cntlid_ida;
147
148 struct list_head hosts;
149 bool allow_any_host;
150
151 u16 max_qid;
152
153 u64 ver;
154 char *subsysnqn;
155
156 struct config_group group;
157
158 struct config_group namespaces_group;
159 struct config_group allowed_hosts_group;
160 };
161
to_subsys(struct config_item * item)162 static inline struct nvmet_subsys *to_subsys(struct config_item *item)
163 {
164 return container_of(to_config_group(item), struct nvmet_subsys, group);
165 }
166
namespaces_to_subsys(struct config_item * item)167 static inline struct nvmet_subsys *namespaces_to_subsys(
168 struct config_item *item)
169 {
170 return container_of(to_config_group(item), struct nvmet_subsys,
171 namespaces_group);
172 }
173
174 struct nvmet_host {
175 struct config_group group;
176 };
177
to_host(struct config_item * item)178 static inline struct nvmet_host *to_host(struct config_item *item)
179 {
180 return container_of(to_config_group(item), struct nvmet_host, group);
181 }
182
nvmet_host_name(struct nvmet_host * host)183 static inline char *nvmet_host_name(struct nvmet_host *host)
184 {
185 return config_item_name(&host->group.cg_item);
186 }
187
188 struct nvmet_host_link {
189 struct list_head entry;
190 struct nvmet_host *host;
191 };
192
193 struct nvmet_subsys_link {
194 struct list_head entry;
195 struct nvmet_subsys *subsys;
196 };
197
198 struct nvmet_req;
199 struct nvmet_fabrics_ops {
200 struct module *owner;
201 unsigned int type;
202 unsigned int sqe_inline_size;
203 unsigned int msdbd;
204 bool has_keyed_sgls : 1;
205 void (*queue_response)(struct nvmet_req *req);
206 int (*add_port)(struct nvmet_port *port);
207 void (*remove_port)(struct nvmet_port *port);
208 void (*delete_ctrl)(struct nvmet_ctrl *ctrl);
209 };
210
211 #define NVMET_MAX_INLINE_BIOVEC 8
212
213 struct nvmet_req {
214 struct nvme_command *cmd;
215 struct nvme_completion *rsp;
216 struct nvmet_sq *sq;
217 struct nvmet_cq *cq;
218 struct nvmet_ns *ns;
219 struct scatterlist *sg;
220 struct bio inline_bio;
221 struct bio_vec inline_bvec[NVMET_MAX_INLINE_BIOVEC];
222 int sg_cnt;
223 size_t data_len;
224
225 struct nvmet_port *port;
226
227 void (*execute)(struct nvmet_req *req);
228 struct nvmet_fabrics_ops *ops;
229 };
230
nvmet_set_status(struct nvmet_req * req,u16 status)231 static inline void nvmet_set_status(struct nvmet_req *req, u16 status)
232 {
233 req->rsp->status = cpu_to_le16(status << 1);
234 }
235
nvmet_set_result(struct nvmet_req * req,u32 result)236 static inline void nvmet_set_result(struct nvmet_req *req, u32 result)
237 {
238 req->rsp->result = cpu_to_le32(result);
239 }
240
241 /*
242 * NVMe command writes actually are DMA reads for us on the target side.
243 */
244 static inline enum dma_data_direction
nvmet_data_dir(struct nvmet_req * req)245 nvmet_data_dir(struct nvmet_req *req)
246 {
247 return nvme_is_write(req->cmd) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
248 }
249
250 struct nvmet_async_event {
251 struct list_head entry;
252 u8 event_type;
253 u8 event_info;
254 u8 log_page;
255 };
256
257 int nvmet_parse_connect_cmd(struct nvmet_req *req);
258 int nvmet_parse_io_cmd(struct nvmet_req *req);
259 int nvmet_parse_admin_cmd(struct nvmet_req *req);
260 int nvmet_parse_discovery_cmd(struct nvmet_req *req);
261 int nvmet_parse_fabrics_cmd(struct nvmet_req *req);
262
263 bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq,
264 struct nvmet_sq *sq, struct nvmet_fabrics_ops *ops);
265 void nvmet_req_complete(struct nvmet_req *req, u16 status);
266
267 void nvmet_cq_setup(struct nvmet_ctrl *ctrl, struct nvmet_cq *cq, u16 qid,
268 u16 size);
269 void nvmet_sq_setup(struct nvmet_ctrl *ctrl, struct nvmet_sq *sq, u16 qid,
270 u16 size);
271 void nvmet_sq_destroy(struct nvmet_sq *sq);
272 int nvmet_sq_init(struct nvmet_sq *sq);
273
274 void nvmet_ctrl_fatal_error(struct nvmet_ctrl *ctrl);
275
276 void nvmet_update_cc(struct nvmet_ctrl *ctrl, u32 new);
277 u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn,
278 struct nvmet_req *req, u32 kato, struct nvmet_ctrl **ctrlp);
279 u16 nvmet_ctrl_find_get(const char *subsysnqn, const char *hostnqn, u16 cntlid,
280 struct nvmet_req *req, struct nvmet_ctrl **ret);
281 void nvmet_ctrl_put(struct nvmet_ctrl *ctrl);
282
283 struct nvmet_subsys *nvmet_subsys_alloc(const char *subsysnqn,
284 enum nvme_subsys_type type);
285 void nvmet_subsys_put(struct nvmet_subsys *subsys);
286
287 struct nvmet_ns *nvmet_find_namespace(struct nvmet_ctrl *ctrl, __le32 nsid);
288 void nvmet_put_namespace(struct nvmet_ns *ns);
289 int nvmet_ns_enable(struct nvmet_ns *ns);
290 void nvmet_ns_disable(struct nvmet_ns *ns);
291 struct nvmet_ns *nvmet_ns_alloc(struct nvmet_subsys *subsys, u32 nsid);
292 void nvmet_ns_free(struct nvmet_ns *ns);
293
294 int nvmet_register_transport(struct nvmet_fabrics_ops *ops);
295 void nvmet_unregister_transport(struct nvmet_fabrics_ops *ops);
296
297 int nvmet_enable_port(struct nvmet_port *port);
298 void nvmet_disable_port(struct nvmet_port *port);
299
300 void nvmet_referral_enable(struct nvmet_port *parent, struct nvmet_port *port);
301 void nvmet_referral_disable(struct nvmet_port *port);
302
303 u16 nvmet_copy_to_sgl(struct nvmet_req *req, off_t off, const void *buf,
304 size_t len);
305 u16 nvmet_copy_from_sgl(struct nvmet_req *req, off_t off, void *buf,
306 size_t len);
307
308 u32 nvmet_get_log_page_len(struct nvme_command *cmd);
309
310 #define NVMET_QUEUE_SIZE 1024
311 #define NVMET_NR_QUEUES 64
312 #define NVMET_MAX_CMD NVMET_QUEUE_SIZE
313 #define NVMET_KAS 10
314 #define NVMET_DISC_KATO 120
315
316 int __init nvmet_init_configfs(void);
317 void __exit nvmet_exit_configfs(void);
318
319 int __init nvmet_init_discovery(void);
320 void nvmet_exit_discovery(void);
321
322 extern struct nvmet_subsys *nvmet_disc_subsys;
323 extern u64 nvmet_genctr;
324 extern struct rw_semaphore nvmet_config_sem;
325
326 bool nvmet_host_allowed(struct nvmet_req *req, struct nvmet_subsys *subsys,
327 const char *hostnqn);
328
329 #endif /* _NVMET_H */
330