xref: /openbmc/linux/drivers/nvme/target/nvmet.h (revision 9fb29c73)
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/uuid.h>
25 #include <linux/nvme.h>
26 #include <linux/configfs.h>
27 #include <linux/rcupdate.h>
28 #include <linux/blkdev.h>
29 #include <linux/radix-tree.h>
30 
31 #define NVMET_ASYNC_EVENTS		4
32 #define NVMET_ERROR_LOG_SLOTS		128
33 #define NVMET_NO_ERROR_LOC		((u16)-1)
34 
35 /*
36  * Supported optional AENs:
37  */
38 #define NVMET_AEN_CFG_OPTIONAL \
39 	(NVME_AEN_CFG_NS_ATTR | NVME_AEN_CFG_ANA_CHANGE)
40 #define NVMET_DISC_AEN_CFG_OPTIONAL \
41 	(NVME_AEN_CFG_DISC_CHANGE)
42 
43 /*
44  * Plus mandatory SMART AENs (we'll never send them, but allow enabling them):
45  */
46 #define NVMET_AEN_CFG_ALL \
47 	(NVME_SMART_CRIT_SPARE | NVME_SMART_CRIT_TEMPERATURE | \
48 	 NVME_SMART_CRIT_RELIABILITY | NVME_SMART_CRIT_MEDIA | \
49 	 NVME_SMART_CRIT_VOLATILE_MEMORY | NVMET_AEN_CFG_OPTIONAL)
50 
51 /* Helper Macros when NVMe error is NVME_SC_CONNECT_INVALID_PARAM
52  * The 16 bit shift is to set IATTR bit to 1, which means offending
53  * offset starts in the data section of connect()
54  */
55 #define IPO_IATTR_CONNECT_DATA(x)	\
56 	(cpu_to_le32((1 << 16) | (offsetof(struct nvmf_connect_data, x))))
57 #define IPO_IATTR_CONNECT_SQE(x)	\
58 	(cpu_to_le32(offsetof(struct nvmf_connect_command, x)))
59 
60 struct nvmet_ns {
61 	struct list_head	dev_link;
62 	struct percpu_ref	ref;
63 	struct block_device	*bdev;
64 	struct file		*file;
65 	bool			readonly;
66 	u32			nsid;
67 	u32			blksize_shift;
68 	loff_t			size;
69 	u8			nguid[16];
70 	uuid_t			uuid;
71 	u32			anagrpid;
72 
73 	bool			buffered_io;
74 	bool			enabled;
75 	struct nvmet_subsys	*subsys;
76 	const char		*device_path;
77 
78 	struct config_group	device_group;
79 	struct config_group	group;
80 
81 	struct completion	disable_done;
82 	mempool_t		*bvec_pool;
83 	struct kmem_cache	*bvec_cache;
84 
85 	int			use_p2pmem;
86 	struct pci_dev		*p2p_dev;
87 };
88 
89 static inline struct nvmet_ns *to_nvmet_ns(struct config_item *item)
90 {
91 	return container_of(to_config_group(item), struct nvmet_ns, group);
92 }
93 
94 static inline struct device *nvmet_ns_dev(struct nvmet_ns *ns)
95 {
96 	return ns->bdev ? disk_to_dev(ns->bdev->bd_disk) : NULL;
97 }
98 
99 struct nvmet_cq {
100 	u16			qid;
101 	u16			size;
102 };
103 
104 struct nvmet_sq {
105 	struct nvmet_ctrl	*ctrl;
106 	struct percpu_ref	ref;
107 	u16			qid;
108 	u16			size;
109 	u32			sqhd;
110 	bool			sqhd_disabled;
111 	struct completion	free_done;
112 	struct completion	confirm_done;
113 };
114 
115 struct nvmet_ana_group {
116 	struct config_group	group;
117 	struct nvmet_port	*port;
118 	u32			grpid;
119 };
120 
121 static inline struct nvmet_ana_group *to_ana_group(struct config_item *item)
122 {
123 	return container_of(to_config_group(item), struct nvmet_ana_group,
124 			group);
125 }
126 
127 /**
128  * struct nvmet_port -	Common structure to keep port
129  *				information for the target.
130  * @entry:		Entry into referrals or transport list.
131  * @disc_addr:		Address information is stored in a format defined
132  *				for a discovery log page entry.
133  * @group:		ConfigFS group for this element's folder.
134  * @priv:		Private data for the transport.
135  */
136 struct nvmet_port {
137 	struct list_head		entry;
138 	struct nvmf_disc_rsp_page_entry	disc_addr;
139 	struct config_group		group;
140 	struct config_group		subsys_group;
141 	struct list_head		subsystems;
142 	struct config_group		referrals_group;
143 	struct list_head		referrals;
144 	struct list_head		global_entry;
145 	struct config_group		ana_groups_group;
146 	struct nvmet_ana_group		ana_default_group;
147 	enum nvme_ana_state		*ana_state;
148 	void				*priv;
149 	bool				enabled;
150 	int				inline_data_size;
151 };
152 
153 static inline struct nvmet_port *to_nvmet_port(struct config_item *item)
154 {
155 	return container_of(to_config_group(item), struct nvmet_port,
156 			group);
157 }
158 
159 static inline struct nvmet_port *ana_groups_to_port(
160 		struct config_item *item)
161 {
162 	return container_of(to_config_group(item), struct nvmet_port,
163 			ana_groups_group);
164 }
165 
166 struct nvmet_ctrl {
167 	struct nvmet_subsys	*subsys;
168 	struct nvmet_cq		**cqs;
169 	struct nvmet_sq		**sqs;
170 
171 	bool			cmd_seen;
172 
173 	struct mutex		lock;
174 	u64			cap;
175 	u32			cc;
176 	u32			csts;
177 
178 	uuid_t			hostid;
179 	u16			cntlid;
180 	u32			kato;
181 
182 	struct nvmet_port	*port;
183 
184 	u32			aen_enabled;
185 	unsigned long		aen_masked;
186 	struct nvmet_req	*async_event_cmds[NVMET_ASYNC_EVENTS];
187 	unsigned int		nr_async_event_cmds;
188 	struct list_head	async_events;
189 	struct work_struct	async_event_work;
190 
191 	struct list_head	subsys_entry;
192 	struct kref		ref;
193 	struct delayed_work	ka_work;
194 	struct work_struct	fatal_err_work;
195 
196 	const struct nvmet_fabrics_ops *ops;
197 
198 	__le32			*changed_ns_list;
199 	u32			nr_changed_ns;
200 
201 	char			subsysnqn[NVMF_NQN_FIELD_LEN];
202 	char			hostnqn[NVMF_NQN_FIELD_LEN];
203 
204 	struct device		*p2p_client;
205 	struct radix_tree_root	p2p_ns_map;
206 
207 	spinlock_t		error_lock;
208 	u64			err_counter;
209 	struct nvme_error_slot	slots[NVMET_ERROR_LOG_SLOTS];
210 };
211 
212 struct nvmet_subsys {
213 	enum nvme_subsys_type	type;
214 
215 	struct mutex		lock;
216 	struct kref		ref;
217 
218 	struct list_head	namespaces;
219 	unsigned int		nr_namespaces;
220 	unsigned int		max_nsid;
221 
222 	struct list_head	ctrls;
223 
224 	struct list_head	hosts;
225 	bool			allow_any_host;
226 
227 	u16			max_qid;
228 
229 	u64			ver;
230 	u64			serial;
231 	char			*subsysnqn;
232 
233 	struct config_group	group;
234 
235 	struct config_group	namespaces_group;
236 	struct config_group	allowed_hosts_group;
237 };
238 
239 static inline struct nvmet_subsys *to_subsys(struct config_item *item)
240 {
241 	return container_of(to_config_group(item), struct nvmet_subsys, group);
242 }
243 
244 static inline struct nvmet_subsys *namespaces_to_subsys(
245 		struct config_item *item)
246 {
247 	return container_of(to_config_group(item), struct nvmet_subsys,
248 			namespaces_group);
249 }
250 
251 struct nvmet_host {
252 	struct config_group	group;
253 };
254 
255 static inline struct nvmet_host *to_host(struct config_item *item)
256 {
257 	return container_of(to_config_group(item), struct nvmet_host, group);
258 }
259 
260 static inline char *nvmet_host_name(struct nvmet_host *host)
261 {
262 	return config_item_name(&host->group.cg_item);
263 }
264 
265 struct nvmet_host_link {
266 	struct list_head	entry;
267 	struct nvmet_host	*host;
268 };
269 
270 struct nvmet_subsys_link {
271 	struct list_head	entry;
272 	struct nvmet_subsys	*subsys;
273 };
274 
275 struct nvmet_req;
276 struct nvmet_fabrics_ops {
277 	struct module *owner;
278 	unsigned int type;
279 	unsigned int msdbd;
280 	bool has_keyed_sgls : 1;
281 	void (*queue_response)(struct nvmet_req *req);
282 	int (*add_port)(struct nvmet_port *port);
283 	void (*remove_port)(struct nvmet_port *port);
284 	void (*delete_ctrl)(struct nvmet_ctrl *ctrl);
285 	void (*disc_traddr)(struct nvmet_req *req,
286 			struct nvmet_port *port, char *traddr);
287 	u16 (*install_queue)(struct nvmet_sq *nvme_sq);
288 };
289 
290 #define NVMET_MAX_INLINE_BIOVEC	8
291 #define NVMET_MAX_INLINE_DATA_LEN NVMET_MAX_INLINE_BIOVEC * PAGE_SIZE
292 
293 struct nvmet_req {
294 	struct nvme_command	*cmd;
295 	struct nvme_completion	*rsp;
296 	struct nvmet_sq		*sq;
297 	struct nvmet_cq		*cq;
298 	struct nvmet_ns		*ns;
299 	struct scatterlist	*sg;
300 	struct bio_vec		inline_bvec[NVMET_MAX_INLINE_BIOVEC];
301 	union {
302 		struct {
303 			struct bio      inline_bio;
304 		} b;
305 		struct {
306 			bool			mpool_alloc;
307 			struct kiocb            iocb;
308 			struct bio_vec          *bvec;
309 			struct work_struct      work;
310 		} f;
311 	};
312 	int			sg_cnt;
313 	/* data length as parsed from the command: */
314 	size_t			data_len;
315 	/* data length as parsed from the SGL descriptor: */
316 	size_t			transfer_len;
317 
318 	struct nvmet_port	*port;
319 
320 	void (*execute)(struct nvmet_req *req);
321 	const struct nvmet_fabrics_ops *ops;
322 
323 	struct pci_dev		*p2p_dev;
324 	struct device		*p2p_client;
325 	u16			error_loc;
326 	u64			error_slba;
327 };
328 
329 extern struct workqueue_struct *buffered_io_wq;
330 
331 static inline void nvmet_set_result(struct nvmet_req *req, u32 result)
332 {
333 	req->rsp->result.u32 = cpu_to_le32(result);
334 }
335 
336 /*
337  * NVMe command writes actually are DMA reads for us on the target side.
338  */
339 static inline enum dma_data_direction
340 nvmet_data_dir(struct nvmet_req *req)
341 {
342 	return nvme_is_write(req->cmd) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
343 }
344 
345 struct nvmet_async_event {
346 	struct list_head	entry;
347 	u8			event_type;
348 	u8			event_info;
349 	u8			log_page;
350 };
351 
352 static inline void nvmet_clear_aen_bit(struct nvmet_req *req, u32 bn)
353 {
354 	int rae = le32_to_cpu(req->cmd->common.cdw10) & 1 << 15;
355 
356 	if (!rae)
357 		clear_bit(bn, &req->sq->ctrl->aen_masked);
358 }
359 
360 static inline bool nvmet_aen_bit_disabled(struct nvmet_ctrl *ctrl, u32 bn)
361 {
362 	if (!(READ_ONCE(ctrl->aen_enabled) & (1 << bn)))
363 		return true;
364 	return test_and_set_bit(bn, &ctrl->aen_masked);
365 }
366 
367 void nvmet_get_feat_kato(struct nvmet_req *req);
368 void nvmet_get_feat_async_event(struct nvmet_req *req);
369 u16 nvmet_set_feat_kato(struct nvmet_req *req);
370 u16 nvmet_set_feat_async_event(struct nvmet_req *req, u32 mask);
371 void nvmet_execute_async_event(struct nvmet_req *req);
372 
373 u16 nvmet_parse_connect_cmd(struct nvmet_req *req);
374 u16 nvmet_bdev_parse_io_cmd(struct nvmet_req *req);
375 u16 nvmet_file_parse_io_cmd(struct nvmet_req *req);
376 u16 nvmet_parse_admin_cmd(struct nvmet_req *req);
377 u16 nvmet_parse_discovery_cmd(struct nvmet_req *req);
378 u16 nvmet_parse_fabrics_cmd(struct nvmet_req *req);
379 
380 bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq,
381 		struct nvmet_sq *sq, const struct nvmet_fabrics_ops *ops);
382 void nvmet_req_uninit(struct nvmet_req *req);
383 void nvmet_req_execute(struct nvmet_req *req);
384 void nvmet_req_complete(struct nvmet_req *req, u16 status);
385 int nvmet_req_alloc_sgl(struct nvmet_req *req);
386 void nvmet_req_free_sgl(struct nvmet_req *req);
387 
388 void nvmet_execute_keep_alive(struct nvmet_req *req);
389 
390 void nvmet_cq_setup(struct nvmet_ctrl *ctrl, struct nvmet_cq *cq, u16 qid,
391 		u16 size);
392 void nvmet_sq_setup(struct nvmet_ctrl *ctrl, struct nvmet_sq *sq, u16 qid,
393 		u16 size);
394 void nvmet_sq_destroy(struct nvmet_sq *sq);
395 int nvmet_sq_init(struct nvmet_sq *sq);
396 
397 void nvmet_ctrl_fatal_error(struct nvmet_ctrl *ctrl);
398 
399 void nvmet_update_cc(struct nvmet_ctrl *ctrl, u32 new);
400 u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn,
401 		struct nvmet_req *req, u32 kato, struct nvmet_ctrl **ctrlp);
402 u16 nvmet_ctrl_find_get(const char *subsysnqn, const char *hostnqn, u16 cntlid,
403 		struct nvmet_req *req, struct nvmet_ctrl **ret);
404 void nvmet_ctrl_put(struct nvmet_ctrl *ctrl);
405 u16 nvmet_check_ctrl_status(struct nvmet_req *req, struct nvme_command *cmd);
406 
407 struct nvmet_subsys *nvmet_subsys_alloc(const char *subsysnqn,
408 		enum nvme_subsys_type type);
409 void nvmet_subsys_put(struct nvmet_subsys *subsys);
410 void nvmet_subsys_del_ctrls(struct nvmet_subsys *subsys);
411 
412 struct nvmet_ns *nvmet_find_namespace(struct nvmet_ctrl *ctrl, __le32 nsid);
413 void nvmet_put_namespace(struct nvmet_ns *ns);
414 int nvmet_ns_enable(struct nvmet_ns *ns);
415 void nvmet_ns_disable(struct nvmet_ns *ns);
416 struct nvmet_ns *nvmet_ns_alloc(struct nvmet_subsys *subsys, u32 nsid);
417 void nvmet_ns_free(struct nvmet_ns *ns);
418 
419 void nvmet_send_ana_event(struct nvmet_subsys *subsys,
420 		struct nvmet_port *port);
421 void nvmet_port_send_ana_event(struct nvmet_port *port);
422 
423 int nvmet_register_transport(const struct nvmet_fabrics_ops *ops);
424 void nvmet_unregister_transport(const struct nvmet_fabrics_ops *ops);
425 
426 int nvmet_enable_port(struct nvmet_port *port);
427 void nvmet_disable_port(struct nvmet_port *port);
428 
429 void nvmet_referral_enable(struct nvmet_port *parent, struct nvmet_port *port);
430 void nvmet_referral_disable(struct nvmet_port *parent, struct nvmet_port *port);
431 
432 u16 nvmet_copy_to_sgl(struct nvmet_req *req, off_t off, const void *buf,
433 		size_t len);
434 u16 nvmet_copy_from_sgl(struct nvmet_req *req, off_t off, void *buf,
435 		size_t len);
436 u16 nvmet_zero_sgl(struct nvmet_req *req, off_t off, size_t len);
437 
438 u32 nvmet_get_log_page_len(struct nvme_command *cmd);
439 
440 extern struct list_head *nvmet_ports;
441 void nvmet_port_disc_changed(struct nvmet_port *port,
442 		struct nvmet_subsys *subsys);
443 void nvmet_subsys_disc_changed(struct nvmet_subsys *subsys,
444 		struct nvmet_host *host);
445 void nvmet_add_async_event(struct nvmet_ctrl *ctrl, u8 event_type,
446 		u8 event_info, u8 log_page);
447 
448 #define NVMET_QUEUE_SIZE	1024
449 #define NVMET_NR_QUEUES		128
450 #define NVMET_MAX_CMD		NVMET_QUEUE_SIZE
451 
452 /*
453  * Nice round number that makes a list of nsids fit into a page.
454  * Should become tunable at some point in the future.
455  */
456 #define NVMET_MAX_NAMESPACES	1024
457 
458 /*
459  * 0 is not a valid ANA group ID, so we start numbering at 1.
460  *
461  * ANA Group 1 exists without manual intervention, has namespaces assigned to it
462  * by default, and is available in an optimized state through all ports.
463  */
464 #define NVMET_MAX_ANAGRPS	128
465 #define NVMET_DEFAULT_ANA_GRPID	1
466 
467 #define NVMET_KAS		10
468 #define NVMET_DISC_KATO_MS		120000
469 
470 int __init nvmet_init_configfs(void);
471 void __exit nvmet_exit_configfs(void);
472 
473 int __init nvmet_init_discovery(void);
474 void nvmet_exit_discovery(void);
475 
476 extern struct nvmet_subsys *nvmet_disc_subsys;
477 extern struct rw_semaphore nvmet_config_sem;
478 
479 extern u32 nvmet_ana_group_enabled[NVMET_MAX_ANAGRPS + 1];
480 extern u64 nvmet_ana_chgcnt;
481 extern struct rw_semaphore nvmet_ana_sem;
482 
483 bool nvmet_host_allowed(struct nvmet_subsys *subsys, const char *hostnqn);
484 
485 int nvmet_bdev_ns_enable(struct nvmet_ns *ns);
486 int nvmet_file_ns_enable(struct nvmet_ns *ns);
487 void nvmet_bdev_ns_disable(struct nvmet_ns *ns);
488 void nvmet_file_ns_disable(struct nvmet_ns *ns);
489 u16 nvmet_bdev_flush(struct nvmet_req *req);
490 u16 nvmet_file_flush(struct nvmet_req *req);
491 void nvmet_ns_changed(struct nvmet_subsys *subsys, u32 nsid);
492 
493 static inline u32 nvmet_rw_len(struct nvmet_req *req)
494 {
495 	return ((u32)le16_to_cpu(req->cmd->rw.length) + 1) <<
496 			req->ns->blksize_shift;
497 }
498 
499 u16 errno_to_nvme_status(struct nvmet_req *req, int errno);
500 #endif /* _NVMET_H */
501