xref: /spdk/module/bdev/raid/bdev_raid.h (revision 7b8c7efe8fe5cbfb09d5ebff2fbad7ce49c7504d)
1 /*   SPDX-License-Identifier: BSD-3-Clause
2  *   Copyright (C) 2018 Intel Corporation.
3  *   All rights reserved.
4  */
5 
6 #ifndef SPDK_BDEV_RAID_INTERNAL_H
7 #define SPDK_BDEV_RAID_INTERNAL_H
8 
9 #include "spdk/bdev_module.h"
10 #include "spdk/uuid.h"
11 
12 #define RAID_BDEV_MIN_DATA_OFFSET_SIZE	(1024*1024) /* 1 MiB */
13 
14 enum raid_level {
15 	INVALID_RAID_LEVEL	= -1,
16 	RAID0			= 0,
17 	RAID1			= 1,
18 	RAID5F			= 95, /* 0x5f */
19 	CONCAT			= 99,
20 };
21 
22 /*
23  * Raid state describes the state of the raid. This raid bdev can be either in
24  * configured list or configuring list
25  */
26 enum raid_bdev_state {
27 	/* raid bdev is ready and is seen by upper layers */
28 	RAID_BDEV_STATE_ONLINE,
29 
30 	/*
31 	 * raid bdev is configuring, not all underlying bdevs are present.
32 	 * And can't be seen by upper layers.
33 	 */
34 	RAID_BDEV_STATE_CONFIGURING,
35 
36 	/*
37 	 * In offline state, raid bdev layer will complete all incoming commands without
38 	 * submitting to underlying base nvme bdevs
39 	 */
40 	RAID_BDEV_STATE_OFFLINE,
41 
42 	/* raid bdev state max, new states should be added before this */
43 	RAID_BDEV_STATE_MAX
44 };
45 
46 enum raid_process_type {
47 	RAID_PROCESS_NONE,
48 	RAID_PROCESS_REBUILD,
49 	RAID_PROCESS_MAX
50 };
51 
52 typedef void (*raid_base_bdev_cb)(void *ctx, int status);
53 
54 /*
55  * raid_base_bdev_info contains information for the base bdevs which are part of some
56  * raid. This structure contains the per base bdev information. Whatever is
57  * required per base device for raid bdev will be kept here
58  */
59 struct raid_base_bdev_info {
60 	/* The raid bdev that this base bdev belongs to */
61 	struct raid_bdev	*raid_bdev;
62 
63 	/* name of the bdev */
64 	char			*name;
65 
66 	/* uuid of the bdev */
67 	struct spdk_uuid	uuid;
68 
69 	/*
70 	 * Pointer to base bdev descriptor opened by raid bdev. This is NULL when the bdev for
71 	 * this slot is missing.
72 	 */
73 	struct spdk_bdev_desc	*desc;
74 
75 	/* offset in blocks from the start of the base bdev to the start of the data region */
76 	uint64_t		data_offset;
77 
78 	/* size in blocks of the base bdev's data region */
79 	uint64_t		data_size;
80 
81 	/*
82 	 * When underlying base device calls the hot plug function on drive removal,
83 	 * this flag will be set and later after doing some processing, base device
84 	 * descriptor will be closed
85 	 */
86 	bool			remove_scheduled;
87 
88 	/* callback for base bdev removal */
89 	raid_base_bdev_cb	remove_cb;
90 
91 	/* context of the callback */
92 	void			*remove_cb_ctx;
93 
94 	/* Hold the number of blocks to know how large the base bdev is resized. */
95 	uint64_t		blockcnt;
96 
97 	/* io channel for the app thread */
98 	struct spdk_io_channel	*app_thread_ch;
99 
100 	/* Set to true when base bdev has completed the configuration process */
101 	bool			is_configured;
102 
103 	/* callback for base bdev configuration */
104 	raid_base_bdev_cb	configure_cb;
105 
106 	/* context of the callback */
107 	void			*configure_cb_ctx;
108 };
109 
110 struct raid_bdev_io;
111 typedef void (*raid_bdev_io_completion_cb)(struct raid_bdev_io *raid_io,
112 		enum spdk_bdev_io_status status);
113 
114 /*
115  * raid_bdev_io is the context part of bdev_io. It contains the information
116  * related to bdev_io for a raid bdev
117  */
118 struct raid_bdev_io {
119 	/* The raid bdev associated with this IO */
120 	struct raid_bdev *raid_bdev;
121 
122 	uint64_t offset_blocks;
123 	uint64_t num_blocks;
124 	struct iovec *iovs;
125 	int iovcnt;
126 	enum spdk_bdev_io_type type;
127 	struct spdk_memory_domain *memory_domain;
128 	void *memory_domain_ctx;
129 	void *md_buf;
130 
131 	/* WaitQ entry, used only in waitq logic */
132 	struct spdk_bdev_io_wait_entry	waitq_entry;
133 
134 	/* Context of the original channel for this IO */
135 	struct raid_bdev_io_channel	*raid_ch;
136 
137 	/* Used for tracking progress on io requests sent to member disks. */
138 	uint64_t			base_bdev_io_remaining;
139 	uint8_t				base_bdev_io_submitted;
140 	enum spdk_bdev_io_status	base_bdev_io_status;
141 
142 	/* Private data for the raid module */
143 	void				*module_private;
144 
145 	/* Custom completion callback. Overrides bdev_io completion if set. */
146 	raid_bdev_io_completion_cb	completion_cb;
147 
148 	struct {
149 		uint64_t		offset;
150 		struct iovec		*iov;
151 		struct iovec		iov_copy;
152 	} split;
153 };
154 
155 struct raid_bdev_process_request {
156 	struct raid_bdev_process *process;
157 	struct raid_base_bdev_info *target;
158 	struct spdk_io_channel *target_ch;
159 	uint64_t offset_blocks;
160 	uint32_t num_blocks;
161 	struct iovec iov;
162 	void *md_buf;
163 	/* bdev_io is raid_io's driver_ctx - don't reorder them!
164 	 * These are needed for re-using raid module I/O functions for process I/O. */
165 	struct spdk_bdev_io bdev_io;
166 	struct raid_bdev_io raid_io;
167 	TAILQ_ENTRY(raid_bdev_process_request) link;
168 };
169 
170 /*
171  * raid_bdev is the single entity structure which contains SPDK block device
172  * and the information related to any raid bdev either configured or
173  * in configuring list. io device is created on this.
174  */
175 struct raid_bdev {
176 	/* raid bdev device, this will get registered in bdev layer */
177 	struct spdk_bdev		bdev;
178 
179 	/* the raid bdev descriptor, opened for internal use */
180 	struct spdk_bdev_desc		*self_desc;
181 
182 	/* link of raid bdev to link it to global raid bdev list */
183 	TAILQ_ENTRY(raid_bdev)		global_link;
184 
185 	/* array of base bdev info */
186 	struct raid_base_bdev_info	*base_bdev_info;
187 
188 	/* strip size of raid bdev in blocks */
189 	uint32_t			strip_size;
190 
191 	/* strip size of raid bdev in KB */
192 	uint32_t			strip_size_kb;
193 
194 	/* strip size bit shift for optimized calculation */
195 	uint32_t			strip_size_shift;
196 
197 	/* state of raid bdev */
198 	enum raid_bdev_state		state;
199 
200 	/* number of base bdevs comprising raid bdev  */
201 	uint8_t				num_base_bdevs;
202 
203 	/* number of base bdevs discovered */
204 	uint8_t				num_base_bdevs_discovered;
205 
206 	/*
207 	 * Number of operational base bdevs, i.e. how many we know/expect to be working. This
208 	 * will be less than num_base_bdevs when starting a degraded array.
209 	 */
210 	uint8_t				num_base_bdevs_operational;
211 
212 	/* minimum number of viable base bdevs that are required by array to operate */
213 	uint8_t				min_base_bdevs_operational;
214 
215 	/* Raid Level of this raid bdev */
216 	enum raid_level			level;
217 
218 	/* Set to true if destroy of this raid bdev is started. */
219 	bool				destroy_started;
220 
221 	/* Module for RAID-level specific operations */
222 	struct raid_bdev_module		*module;
223 
224 	/* Private data for the raid module */
225 	void				*module_private;
226 
227 	/* Superblock */
228 	bool				superblock_enabled;
229 	struct raid_bdev_superblock	*sb;
230 
231 	/* Superblock buffer used for I/O */
232 	void				*sb_io_buf;
233 	uint32_t			sb_io_buf_size;
234 
235 	/* Raid bdev background process, e.g. rebuild */
236 	struct raid_bdev_process	*process;
237 };
238 
239 #define RAID_FOR_EACH_BASE_BDEV(r, i) \
240 	for (i = r->base_bdev_info; i < r->base_bdev_info + r->num_base_bdevs; i++)
241 
242 struct raid_bdev_io_channel;
243 
244 /* TAIL head for raid bdev list */
245 TAILQ_HEAD(raid_all_tailq, raid_bdev);
246 
247 extern struct raid_all_tailq		g_raid_bdev_list;
248 
249 typedef void (*raid_bdev_destruct_cb)(void *cb_ctx, int rc);
250 
251 int raid_bdev_create(const char *name, uint32_t strip_size, uint8_t num_base_bdevs,
252 		     enum raid_level level, bool superblock, const struct spdk_uuid *uuid,
253 		     struct raid_bdev **raid_bdev_out);
254 void raid_bdev_delete(struct raid_bdev *raid_bdev, raid_bdev_destruct_cb cb_fn, void *cb_ctx);
255 int raid_bdev_add_base_bdev(struct raid_bdev *raid_bdev, const char *name,
256 			    raid_base_bdev_cb cb_fn, void *cb_ctx);
257 struct raid_bdev *raid_bdev_find_by_name(const char *name);
258 enum raid_level raid_bdev_str_to_level(const char *str);
259 const char *raid_bdev_level_to_str(enum raid_level level);
260 enum raid_bdev_state raid_bdev_str_to_state(const char *str);
261 const char *raid_bdev_state_to_str(enum raid_bdev_state state);
262 const char *raid_bdev_process_to_str(enum raid_process_type value);
263 void raid_bdev_write_info_json(struct raid_bdev *raid_bdev, struct spdk_json_write_ctx *w);
264 int raid_bdev_remove_base_bdev(struct spdk_bdev *base_bdev, raid_base_bdev_cb cb_fn, void *cb_ctx);
265 
266 /*
267  * RAID module descriptor
268  */
269 struct raid_bdev_module {
270 	/* RAID level implemented by this module */
271 	enum raid_level level;
272 
273 	/* Minimum required number of base bdevs. Must be > 0. */
274 	uint8_t base_bdevs_min;
275 
276 	/*
277 	 * RAID constraint. Determines number of base bdevs that can be removed
278 	 * without failing the array.
279 	 */
280 	struct {
281 		enum {
282 			CONSTRAINT_UNSET = 0,
283 			CONSTRAINT_MAX_BASE_BDEVS_REMOVED,
284 			CONSTRAINT_MIN_BASE_BDEVS_OPERATIONAL,
285 		} type;
286 		uint8_t value;
287 	} base_bdevs_constraint;
288 
289 	/* Set to true if this module supports memory domains. */
290 	bool memory_domains_supported;
291 
292 	/* Set to true if this module supports DIF/DIX */
293 	bool dif_supported;
294 
295 	/*
296 	 * Called when the raid is starting, right before changing the state to
297 	 * online and registering the bdev. Parameters of the bdev like blockcnt
298 	 * should be set here.
299 	 *
300 	 * Non-zero return value will abort the startup process.
301 	 */
302 	int (*start)(struct raid_bdev *raid_bdev);
303 
304 	/*
305 	 * Called when the raid is stopping, right before changing the state to
306 	 * offline and unregistering the bdev. Optional.
307 	 *
308 	 * The function should return false if it is asynchronous. Then, after
309 	 * the async operation has completed and the module is fully stopped
310 	 * raid_bdev_module_stop_done() must be called.
311 	 */
312 	bool (*stop)(struct raid_bdev *raid_bdev);
313 
314 	/* Handler for R/W requests */
315 	void (*submit_rw_request)(struct raid_bdev_io *raid_io);
316 
317 	/* Handler for requests without payload (flush, unmap). Optional. */
318 	void (*submit_null_payload_request)(struct raid_bdev_io *raid_io);
319 
320 	/*
321 	 * Called when the bdev's IO channel is created to get the module's private IO channel.
322 	 * Optional.
323 	 */
324 	struct spdk_io_channel *(*get_io_channel)(struct raid_bdev *raid_bdev);
325 
326 	/*
327 	 * Called when a base_bdev is resized to resize the raid if the condition
328 	 * is satisfied. Optional.
329 	 *
330 	 * Returns true if the resize was performed.
331 	 */
332 	bool (*resize)(struct raid_bdev *raid_bdev);
333 
334 	/* Handler for raid process requests. Required for raid modules with redundancy. */
335 	int (*submit_process_request)(struct raid_bdev_process_request *process_req,
336 				      struct raid_bdev_io_channel *raid_ch);
337 
338 	TAILQ_ENTRY(raid_bdev_module) link;
339 };
340 
341 void raid_bdev_module_list_add(struct raid_bdev_module *raid_module);
342 
343 #define __RAID_MODULE_REGISTER(line) __RAID_MODULE_REGISTER_(line)
344 #define __RAID_MODULE_REGISTER_(line) raid_module_register_##line
345 
346 #define RAID_MODULE_REGISTER(_module)					\
347 __attribute__((constructor)) static void				\
348 __RAID_MODULE_REGISTER(__LINE__)(void)					\
349 {									\
350     raid_bdev_module_list_add(_module);					\
351 }
352 
353 bool raid_bdev_io_complete_part(struct raid_bdev_io *raid_io, uint64_t completed,
354 				enum spdk_bdev_io_status status);
355 void raid_bdev_queue_io_wait(struct raid_bdev_io *raid_io, struct spdk_bdev *bdev,
356 			     struct spdk_io_channel *ch, spdk_bdev_io_wait_cb cb_fn);
357 void raid_bdev_io_complete(struct raid_bdev_io *raid_io, enum spdk_bdev_io_status status);
358 void raid_bdev_module_stop_done(struct raid_bdev *raid_bdev);
359 struct spdk_io_channel *raid_bdev_channel_get_base_channel(struct raid_bdev_io_channel *raid_ch,
360 		uint8_t idx);
361 void *raid_bdev_channel_get_module_ctx(struct raid_bdev_io_channel *raid_ch);
362 void raid_bdev_process_request_complete(struct raid_bdev_process_request *process_req, int status);
363 void raid_bdev_io_init(struct raid_bdev_io *raid_io, struct raid_bdev_io_channel *raid_ch,
364 		       enum spdk_bdev_io_type type, uint64_t offset_blocks,
365 		       uint64_t num_blocks, struct iovec *iovs, int iovcnt, void *md_buf,
366 		       struct spdk_memory_domain *memory_domain, void *memory_domain_ctx);
367 
368 static inline uint8_t
369 raid_bdev_base_bdev_slot(struct raid_base_bdev_info *base_info)
370 {
371 	return base_info - base_info->raid_bdev->base_bdev_info;
372 }
373 
374 int raid_bdev_verify_dix_reftag(struct iovec *iovs, int iovcnt, void *md_buf,
375 				uint64_t num_blocks, struct spdk_bdev *bdev, uint32_t offset_blocks);
376 
377 /**
378  * Raid bdev I/O read/write wrapper for spdk_bdev_readv_blocks_ext function.
379  */
380 int raid_bdev_readv_blocks_ext(struct raid_base_bdev_info *base_info, struct spdk_io_channel *ch,
381 			       struct iovec *iov, int iovcnt, uint64_t offset_blocks,
382 			       uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void *cb_arg,
383 			       struct spdk_bdev_ext_io_opts *opts);
384 
385 /**
386  * Raid bdev I/O read/write wrapper for spdk_bdev_writev_blocks_ext function.
387  */
388 int raid_bdev_writev_blocks_ext(struct raid_base_bdev_info *base_info, struct spdk_io_channel *ch,
389 				struct iovec *iov, int iovcnt, uint64_t offset_blocks,
390 				uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void *cb_arg,
391 				struct spdk_bdev_ext_io_opts *opts);
392 
393 /**
394  * Raid bdev I/O read/write wrapper for spdk_bdev_unmap_blocks function.
395  */
396 static inline int
397 raid_bdev_unmap_blocks(struct raid_base_bdev_info *base_info, struct spdk_io_channel *ch,
398 		       uint64_t offset_blocks, uint64_t num_blocks,
399 		       spdk_bdev_io_completion_cb cb, void *cb_arg)
400 {
401 	return spdk_bdev_unmap_blocks(base_info->desc, ch, base_info->data_offset + offset_blocks,
402 				      num_blocks, cb, cb_arg);
403 }
404 
405 /**
406  * Raid bdev I/O read/write wrapper for spdk_bdev_flush_blocks function.
407  */
408 static inline int
409 raid_bdev_flush_blocks(struct raid_base_bdev_info *base_info, struct spdk_io_channel *ch,
410 		       uint64_t offset_blocks, uint64_t num_blocks,
411 		       spdk_bdev_io_completion_cb cb, void *cb_arg)
412 {
413 	return spdk_bdev_flush_blocks(base_info->desc, ch, base_info->data_offset + offset_blocks,
414 				      num_blocks, cb, cb_arg);
415 }
416 
417 /*
418  * Definitions related to raid bdev superblock
419  */
420 
421 #define RAID_BDEV_SB_VERSION_MAJOR	1
422 #define RAID_BDEV_SB_VERSION_MINOR	0
423 
424 #define RAID_BDEV_SB_NAME_SIZE		64
425 
426 enum raid_bdev_sb_base_bdev_state {
427 	RAID_SB_BASE_BDEV_MISSING	= 0,
428 	RAID_SB_BASE_BDEV_CONFIGURED	= 1,
429 	RAID_SB_BASE_BDEV_FAILED	= 2,
430 	RAID_SB_BASE_BDEV_SPARE		= 3,
431 };
432 
433 struct raid_bdev_sb_base_bdev {
434 	/* uuid of the base bdev */
435 	struct spdk_uuid	uuid;
436 	/* offset in blocks from base device start to the start of raid data area */
437 	uint64_t		data_offset;
438 	/* size in blocks of the base device raid data area */
439 	uint64_t		data_size;
440 	/* state of the base bdev */
441 	uint32_t		state;
442 	/* feature/status flags */
443 	uint32_t		flags;
444 	/* slot number of this base bdev in the raid */
445 	uint8_t			slot;
446 
447 	uint8_t			reserved[23];
448 };
449 SPDK_STATIC_ASSERT(sizeof(struct raid_bdev_sb_base_bdev) == 64, "incorrect size");
450 
451 struct raid_bdev_superblock {
452 #define RAID_BDEV_SB_SIG "SPDKRAID"
453 	uint8_t			signature[8];
454 	struct {
455 		/* incremented when a breaking change in the superblock structure is made */
456 		uint16_t	major;
457 		/* incremented for changes in the superblock that are backward compatible */
458 		uint16_t	minor;
459 	} version;
460 	/* length in bytes of the entire superblock */
461 	uint32_t		length;
462 	/* crc32c checksum of the entire superblock */
463 	uint32_t		crc;
464 	/* feature/status flags */
465 	uint32_t		flags;
466 	/* unique id of the raid bdev */
467 	struct spdk_uuid	uuid;
468 	/* name of the raid bdev */
469 	uint8_t			name[RAID_BDEV_SB_NAME_SIZE];
470 	/* size of the raid bdev in blocks */
471 	uint64_t		raid_size;
472 	/* the raid bdev block size - must be the same for all base bdevs */
473 	uint32_t		block_size;
474 	/* the raid level */
475 	uint32_t		level;
476 	/* strip (chunk) size in blocks */
477 	uint32_t		strip_size;
478 	/* state of the raid */
479 	uint32_t		state;
480 	/* sequence number, incremented on every superblock update */
481 	uint64_t		seq_number;
482 	/* number of raid base devices */
483 	uint8_t			num_base_bdevs;
484 
485 	uint8_t			reserved[118];
486 
487 	/* size of the base bdevs array */
488 	uint8_t			base_bdevs_size;
489 	/* array of base bdev descriptors */
490 	struct raid_bdev_sb_base_bdev base_bdevs[];
491 };
492 SPDK_STATIC_ASSERT(sizeof(struct raid_bdev_superblock) == 256, "incorrect size");
493 
494 #define RAID_BDEV_SB_MAX_LENGTH (sizeof(struct raid_bdev_superblock) + UINT8_MAX * sizeof(struct raid_bdev_sb_base_bdev))
495 
496 SPDK_STATIC_ASSERT(RAID_BDEV_SB_MAX_LENGTH < RAID_BDEV_MIN_DATA_OFFSET_SIZE,
497 		   "Incorrect min data offset");
498 
499 typedef void (*raid_bdev_write_sb_cb)(int status, struct raid_bdev *raid_bdev, void *ctx);
500 typedef void (*raid_bdev_load_sb_cb)(const struct raid_bdev_superblock *sb, int status, void *ctx);
501 
502 int raid_bdev_alloc_superblock(struct raid_bdev *raid_bdev, uint32_t block_size);
503 void raid_bdev_free_superblock(struct raid_bdev *raid_bdev);
504 void raid_bdev_init_superblock(struct raid_bdev *raid_bdev);
505 void raid_bdev_write_superblock(struct raid_bdev *raid_bdev, raid_bdev_write_sb_cb cb,
506 				void *cb_ctx);
507 int raid_bdev_load_base_bdev_superblock(struct spdk_bdev_desc *desc, struct spdk_io_channel *ch,
508 					raid_bdev_load_sb_cb cb, void *cb_ctx);
509 
510 struct spdk_raid_bdev_opts {
511 	/* Size of the background process window in KiB */
512 	uint32_t process_window_size_kb;
513 };
514 
515 void raid_bdev_get_opts(struct spdk_raid_bdev_opts *opts);
516 int raid_bdev_set_opts(const struct spdk_raid_bdev_opts *opts);
517 
518 #endif /* SPDK_BDEV_RAID_INTERNAL_H */
519