xref: /spdk/lib/ftl/utils/ftl_md.c (revision 510f4c134a21b45ff3a5add9ebc6c6cf7e49aeab)
1 /*   SPDX-License-Identifier: BSD-3-Clause
2  *   Copyright (c) Intel Corporation.
3  *   All rights reserved.
4  */
5 
6 #include "spdk/env.h"
7 #include "spdk/bdev_module.h"
8 
9 #include "ftl_core.h"
10 #include "ftl_md.h"
11 #include "ftl_nv_cache_io.h"
12 
13 struct ftl_md;
14 static void io_submit(struct ftl_md *md);
15 static void io_done(struct ftl_md *md);
16 
17 static bool
18 has_mirror(struct ftl_md *md)
19 {
20 	if (md->region) {
21 		if (md->region->mirror_type != FTL_LAYOUT_REGION_TYPE_INVALID) {
22 			return md->mirror_enabled;
23 		}
24 	}
25 
26 	return false;
27 }
28 
29 static int
30 setup_mirror(struct ftl_md *md)
31 {
32 	if (!md->mirror) {
33 		md->mirror = calloc(1, sizeof(*md->mirror));
34 		if (!md->mirror) {
35 			return -ENOMEM;
36 		}
37 		md->mirror_enabled = true;
38 	}
39 
40 	md->mirror->dev = md->dev;
41 	md->mirror->data_blocks = md->data_blocks;
42 	md->mirror->data = md->data;
43 	md->mirror->vss_data = md->vss_data;
44 
45 	/* Set proper region in secondary object */
46 	assert(md->region->mirror_type != FTL_LAYOUT_REGION_TYPE_INVALID);
47 	md->mirror->region = &md->dev->layout.region[md->region->mirror_type];
48 
49 	return 0;
50 }
51 
52 uint64_t
53 ftl_md_xfer_blocks(struct spdk_ftl_dev *dev)
54 {
55 	return 4ULL * dev->xfer_size;
56 }
57 
58 static uint64_t
59 xfer_size(struct ftl_md *md)
60 {
61 	return ftl_md_xfer_blocks(md->dev) * FTL_BLOCK_SIZE;
62 }
63 
64 static void
65 ftl_md_create_heap(struct ftl_md *md, uint64_t vss_blksz)
66 {
67 	md->shm_fd = -1;
68 	md->vss_data = NULL;
69 	md->data = calloc(md->data_blocks, FTL_BLOCK_SIZE + vss_blksz);
70 
71 	if (md->data && vss_blksz) {
72 		md->vss_data = ((char *)md->data) + md->data_blocks * FTL_BLOCK_SIZE;
73 	}
74 }
75 
76 static void
77 ftl_md_destroy_heap(struct ftl_md *md)
78 {
79 	if (md->data) {
80 		free(md->data);
81 		md->data = NULL;
82 		md->vss_data = NULL;
83 	}
84 }
85 
86 static int
87 ftl_wrapper_open(const char *name, int of, mode_t m)
88 {
89 	return open(name, of, m);
90 }
91 
92 static void
93 ftl_md_setup_obj(struct ftl_md *md, int flags,
94 		 const char *name)
95 {
96 	char uuid_str[SPDK_UUID_STRING_LEN];
97 	const char *fmt;
98 
99 	if (!(flags & FTL_MD_CREATE_SHM)) {
100 		assert(false);
101 		return;
102 	}
103 
104 	/* TODO: temporary, define a proper hugetlbfs mountpoint */
105 	fmt = "/dev/hugepages/ftl_%s_%s";
106 	md->shm_mmap_flags = MAP_SHARED;
107 	md->shm_open = ftl_wrapper_open;
108 	md->shm_unlink = unlink;
109 
110 	if (name == NULL ||
111 	    spdk_uuid_fmt_lower(uuid_str, SPDK_UUID_STRING_LEN, &md->dev->conf.uuid) ||
112 	    snprintf(md->name, sizeof(md->name) / sizeof(md->name[0]),
113 		     fmt, uuid_str, name) <= 0) {
114 		md->name[0] = 0;
115 	}
116 }
117 
118 static void
119 ftl_md_invalidate_shm(struct ftl_md *md)
120 {
121 	if (md->dev->sb_shm && md->dev->sb_shm->shm_ready) {
122 		md->dev->init_retry = true;
123 		md->dev->sb_shm->shm_ready = false;
124 	}
125 }
126 
127 static void
128 ftl_md_create_shm(struct ftl_md *md, uint64_t vss_blksz, int flags)
129 {
130 	struct stat shm_stat;
131 	size_t vss_blk_offs;
132 	void *shm_ptr;
133 	int open_flags = O_RDWR;
134 	mode_t open_mode = S_IRUSR | S_IWUSR;
135 
136 	assert(md->shm_open && md->shm_unlink);
137 	md->data = NULL;
138 	md->vss_data = NULL;
139 	md->shm_sz = 0;
140 
141 	/* Must have an object name */
142 	if (md->name[0] == 0) {
143 		assert(false);
144 		return;
145 	}
146 
147 	/* If specified, unlink before create a new SHM object */
148 	if (flags & FTL_MD_CREATE_SHM_NEW) {
149 		if (md->shm_unlink(md->name) < 0 && errno != ENOENT) {
150 			ftl_md_invalidate_shm(md);
151 			return;
152 		}
153 		open_flags += O_CREAT | O_TRUNC;
154 	}
155 
156 	/* Open existing or create a new SHM object, then query its props */
157 	md->shm_fd = md->shm_open(md->name, open_flags, open_mode);
158 	if (md->shm_fd < 0 || fstat(md->shm_fd, &shm_stat) < 0) {
159 		goto err_shm;
160 	}
161 
162 	/* Verify open mode hasn't changed */
163 	if ((shm_stat.st_mode & (S_IRWXU | S_IRWXG | S_IRWXO)) != open_mode) {
164 		goto err_shm;
165 	}
166 
167 	/* Round up the SHM obj size to the nearest blk size (i.e. page size) */
168 	md->shm_sz = spdk_divide_round_up(md->data_blocks * FTL_BLOCK_SIZE, shm_stat.st_blksize);
169 
170 	/* Add some blks for VSS metadata */
171 	vss_blk_offs = md->shm_sz;
172 
173 	if (vss_blksz) {
174 		md->shm_sz += spdk_divide_round_up(md->data_blocks * vss_blksz,
175 						   shm_stat.st_blksize);
176 	}
177 
178 	/* Total SHM obj size */
179 	md->shm_sz *= shm_stat.st_blksize;
180 
181 	/* Set or check the object size - zero init`d in case of set (FTL_MD_CREATE_SHM_NEW) */
182 	if ((shm_stat.st_size == 0 && (ftruncate(md->shm_fd, md->shm_sz) < 0 ||
183 				       (flags & FTL_MD_CREATE_SHM_NEW) == 0))
184 	    || (shm_stat.st_size > 0 && (size_t)shm_stat.st_size != md->shm_sz)) {
185 		goto err_shm;
186 	}
187 
188 	/* Create a virtual memory mapping for the object */
189 	shm_ptr = mmap(NULL, md->shm_sz, PROT_READ | PROT_WRITE, md->shm_mmap_flags,
190 		       md->shm_fd, 0);
191 	if (shm_ptr == MAP_FAILED) {
192 		goto err_shm;
193 	}
194 
195 	md->data = shm_ptr;
196 	if (vss_blksz) {
197 		md->vss_data = ((char *)shm_ptr) + vss_blk_offs * shm_stat.st_blksize;
198 	}
199 
200 	/* Lock the pages in memory (i.e. prevent the pages to be paged out) */
201 	if (mlock(md->data, md->shm_sz) < 0) {
202 		goto err_map;
203 	}
204 
205 	if (spdk_mem_register(md->data, md->shm_sz)) {
206 		goto err_mlock;
207 	}
208 	md->mem_reg = true;
209 
210 	return;
211 
212 	/* Cleanup upon fault */
213 err_mlock:
214 	munlock(md->data, md->shm_sz);
215 
216 err_map:
217 	munmap(md->data, md->shm_sz);
218 	md->data = NULL;
219 	md->vss_data = NULL;
220 	md->shm_sz = 0;
221 
222 err_shm:
223 	if (md->shm_fd >= 0) {
224 		close(md->shm_fd);
225 		md->shm_unlink(md->name);
226 		md->shm_fd = -1;
227 	}
228 	ftl_md_invalidate_shm(md);
229 }
230 
231 static void
232 ftl_md_destroy_shm(struct ftl_md *md, int flags)
233 {
234 	if (!md->data) {
235 		return;
236 	}
237 
238 	assert(md->shm_sz > 0);
239 	if (md->mem_reg) {
240 		spdk_mem_unregister(md->data, md->shm_sz);
241 		md->mem_reg = false;
242 	}
243 
244 	/* Unlock the pages in memory */
245 	munlock(md->data, md->shm_sz);
246 
247 	/* Remove the virtual memory mapping for the object */
248 	munmap(md->data, md->shm_sz);
249 
250 	/* Close SHM object fd */
251 	close(md->shm_fd);
252 
253 	md->data = NULL;
254 	md->vss_data = NULL;
255 
256 	/* If specified, keep the object in SHM */
257 	if (flags & FTL_MD_DESTROY_SHM_KEEP) {
258 		return;
259 	}
260 
261 	/* Otherwise destroy/unlink the object */
262 	assert(md->name[0] != 0 && md->shm_unlink != NULL);
263 	md->shm_unlink(md->name);
264 }
265 
266 struct ftl_md *ftl_md_create(struct spdk_ftl_dev *dev, uint64_t blocks,
267 			     uint64_t vss_blksz, const char *name, int flags,
268 			     const struct ftl_layout_region *region)
269 {
270 	struct ftl_md *md;
271 
272 	md = calloc(1, sizeof(*md));
273 	if (!md) {
274 		return NULL;
275 	}
276 	md->dev = dev;
277 	md->data_blocks = blocks;
278 	md->mirror_enabled = true;
279 
280 	if (flags != FTL_MD_CREATE_NO_MEM) {
281 		if (flags & FTL_MD_CREATE_SHM) {
282 			ftl_md_setup_obj(md, flags, name);
283 			ftl_md_create_shm(md, vss_blksz, flags);
284 		} else {
285 			assert((flags & FTL_MD_CREATE_HEAP) == FTL_MD_CREATE_HEAP);
286 			ftl_md_create_heap(md, vss_blksz);
287 		}
288 
289 		if (!md->data) {
290 			free(md);
291 			return NULL;
292 		}
293 	}
294 
295 	if (region) {
296 		size_t entry_vss_buf_size = vss_blksz * region->entry_size;
297 
298 		if (entry_vss_buf_size) {
299 			md->entry_vss_dma_buf = spdk_malloc(entry_vss_buf_size, FTL_BLOCK_SIZE,
300 							    NULL, SPDK_ENV_LCORE_ID_ANY,
301 							    SPDK_MALLOC_DMA);
302 			if (!md->entry_vss_dma_buf) {
303 				goto err;
304 			}
305 		}
306 
307 		if (ftl_md_set_region(md, region)) {
308 			goto err;
309 		}
310 	}
311 
312 	return md;
313 err:
314 	ftl_md_destroy(md, ftl_md_destroy_region_flags(dev, region->type));
315 	return NULL;
316 }
317 
318 int
319 ftl_md_unlink(struct spdk_ftl_dev *dev, const char *name, int flags)
320 {
321 	struct ftl_md md = { 0 };
322 
323 	if (0 == (flags & FTL_MD_CREATE_SHM)) {
324 		/* Unlink can be called for shared memory only */
325 		return -EINVAL;
326 	}
327 
328 	md.dev = dev;
329 	ftl_md_setup_obj(&md, flags, name);
330 
331 	return md.shm_unlink(md.name);
332 }
333 
334 void
335 ftl_md_destroy(struct ftl_md *md, int flags)
336 {
337 	if (!md) {
338 		return;
339 	}
340 
341 	ftl_md_free_buf(md, flags);
342 
343 	spdk_free(md->entry_vss_dma_buf);
344 
345 	free(md->mirror);
346 	free(md);
347 }
348 
349 void
350 ftl_md_free_buf(struct ftl_md *md, int flags)
351 {
352 	if (!md) {
353 		return;
354 	}
355 
356 	if (md->shm_fd < 0) {
357 		assert(flags == 0);
358 		ftl_md_destroy_heap(md);
359 	} else {
360 		ftl_md_destroy_shm(md, flags);
361 	}
362 }
363 
364 void *
365 ftl_md_get_buffer(struct ftl_md *md)
366 {
367 	return md->data;
368 }
369 
370 uint64_t
371 ftl_md_get_buffer_size(struct ftl_md *md)
372 {
373 	return md->data_blocks * FTL_BLOCK_SIZE;
374 }
375 
376 static void
377 ftl_md_vss_buf_init(union ftl_md_vss *buf, uint32_t count,
378 		    const union ftl_md_vss *vss_pattern)
379 {
380 	while (count) {
381 		count--;
382 		buf[count] = *vss_pattern;
383 	}
384 }
385 
386 union ftl_md_vss *ftl_md_vss_buf_alloc(struct ftl_layout_region *region, uint32_t count)
387 {
388 	union ftl_md_vss *buf = spdk_zmalloc(count * FTL_MD_VSS_SZ, FTL_BLOCK_SIZE, NULL,
389 						     SPDK_ENV_LCORE_ID_ANY,
390 						     SPDK_MALLOC_DMA);
391 
392 	if (!buf) {
393 		return NULL;
394 	}
395 
396 	union ftl_md_vss vss_buf = {0};
397 	vss_buf.version.md_version = region->current.version;
398 	ftl_md_vss_buf_init(buf, count, &vss_buf);
399 	return buf;
400 }
401 
402 union ftl_md_vss *ftl_md_get_vss_buffer(struct ftl_md *md)
403 {
404 	return md->vss_data;
405 }
406 
407 static void
408 io_cleanup(struct ftl_md *md)
409 {
410 	spdk_dma_free(md->io.data);
411 	md->io.data = NULL;
412 
413 	spdk_dma_free(md->io.md);
414 	md->io.md = NULL;
415 }
416 
417 static void
418 exception(void *arg)
419 {
420 	struct ftl_md *md = arg;
421 
422 	md->cb(md->dev, md, -EINVAL);
423 	io_cleanup(md);
424 }
425 
426 static void
427 audit_md_vss_version(struct ftl_md *md, uint64_t blocks)
428 {
429 #if defined(DEBUG)
430 	union ftl_md_vss *vss = md->io.md;
431 	while (blocks) {
432 		blocks--;
433 		assert(vss[blocks].version.md_version == md->region->current.version);
434 	}
435 #endif
436 }
437 
438 static void
439 read_write_blocks_cb(struct spdk_bdev_io *bdev_io, bool success, void *arg)
440 {
441 	struct ftl_md *md = arg;
442 
443 	if (spdk_unlikely(!success)) {
444 		if (md->io.op == FTL_MD_OP_RESTORE && has_mirror(md)) {
445 			md->io.status = -EAGAIN;
446 		} else {
447 			md->io.status = -EIO;
448 		}
449 	} else {
450 		uint64_t blocks = bdev_io->u.bdev.num_blocks;
451 		uint64_t size = blocks * FTL_BLOCK_SIZE;
452 
453 		if (md->io.op == FTL_MD_OP_RESTORE) {
454 			memcpy(md->data + md->io.data_offset, md->io.data, size);
455 
456 			if (md->vss_data) {
457 				uint64_t vss_offset = md->io.data_offset / FTL_BLOCK_SIZE;
458 				vss_offset *= FTL_MD_VSS_SZ;
459 				audit_md_vss_version(md, blocks);
460 				memcpy(md->vss_data + vss_offset, md->io.md, blocks * FTL_MD_VSS_SZ);
461 			}
462 		}
463 
464 		md->io.address += blocks;
465 		md->io.remaining -= blocks;
466 		md->io.data_offset += size;
467 	}
468 
469 	spdk_bdev_free_io(bdev_io);
470 
471 	io_submit(md);
472 }
473 
474 static inline int
475 read_blocks(struct spdk_ftl_dev *dev, struct spdk_bdev_desc *desc,
476 	    struct spdk_io_channel *ch,
477 	    void *buf, void *md_buf,
478 	    uint64_t offset_blocks, uint64_t num_blocks,
479 	    spdk_bdev_io_completion_cb cb, void *cb_arg)
480 {
481 	if (desc == dev->nv_cache.bdev_desc) {
482 		return ftl_nv_cache_bdev_read_blocks_with_md(dev, desc, ch, buf, md_buf,
483 				offset_blocks, num_blocks,
484 				cb, cb_arg);
485 	} else if (md_buf) {
486 		return spdk_bdev_read_blocks_with_md(desc, ch, buf, md_buf,
487 						     offset_blocks, num_blocks,
488 						     cb, cb_arg);
489 	} else {
490 		return spdk_bdev_read_blocks(desc, ch, buf,
491 					     offset_blocks, num_blocks,
492 					     cb, cb_arg);
493 	}
494 }
495 
496 static inline int
497 write_blocks(struct spdk_ftl_dev *dev, struct spdk_bdev_desc *desc,
498 	     struct spdk_io_channel *ch,
499 	     void *buf, void *md_buf,
500 	     uint64_t offset_blocks, uint64_t num_blocks,
501 	     spdk_bdev_io_completion_cb cb, void *cb_arg)
502 {
503 	if (desc == dev->nv_cache.bdev_desc) {
504 		return ftl_nv_cache_bdev_write_blocks_with_md(dev, desc, ch, buf, md_buf,
505 				offset_blocks, num_blocks,
506 				cb, cb_arg);
507 	} else if (md_buf) {
508 		return spdk_bdev_write_blocks_with_md(desc, ch, buf, md_buf, offset_blocks,
509 						      num_blocks, cb, cb_arg);
510 	} else {
511 		return spdk_bdev_write_blocks(desc, ch, buf, offset_blocks, num_blocks, cb, cb_arg);
512 	}
513 }
514 
515 static void
516 read_write_blocks(void *_md)
517 {
518 	struct ftl_md *md = _md;
519 	const struct ftl_layout_region *region = md->region;
520 	uint64_t blocks;
521 	int rc = 0;
522 
523 	blocks = spdk_min(md->io.remaining, ftl_md_xfer_blocks(md->dev));
524 
525 	switch (md->io.op) {
526 	case FTL_MD_OP_RESTORE:
527 		rc = read_blocks(md->dev, region->bdev_desc, region->ioch,
528 				 md->io.data, md->io.md,
529 				 md->io.address, blocks,
530 				 read_write_blocks_cb, md);
531 		break;
532 	case FTL_MD_OP_PERSIST:
533 	case FTL_MD_OP_CLEAR:
534 		rc = write_blocks(md->dev, region->bdev_desc, region->ioch,
535 				  md->io.data, md->io.md,
536 				  md->io.address, blocks,
537 				  read_write_blocks_cb, md);
538 		break;
539 	default:
540 		ftl_abort();
541 	}
542 
543 	if (spdk_unlikely(rc)) {
544 		if (rc == -ENOMEM) {
545 			struct spdk_bdev *bdev = spdk_bdev_desc_get_bdev(region->bdev_desc);
546 			md->io.bdev_io_wait.bdev = bdev;
547 			md->io.bdev_io_wait.cb_fn = read_write_blocks;
548 			md->io.bdev_io_wait.cb_arg = md;
549 			spdk_bdev_queue_io_wait(bdev, region->ioch, &md->io.bdev_io_wait);
550 		} else {
551 			ftl_abort();
552 		}
553 	}
554 }
555 
556 static void
557 io_submit(struct ftl_md *md)
558 {
559 	if (!md->io.remaining || md->io.status) {
560 		io_done(md);
561 		return;
562 	}
563 
564 	if (md->io.op == FTL_MD_OP_PERSIST) {
565 		uint64_t blocks = spdk_min(md->io.remaining, ftl_md_xfer_blocks(md->dev));
566 
567 		memcpy(md->io.data, md->data + md->io.data_offset, FTL_BLOCK_SIZE * blocks);
568 
569 		if (md->vss_data) {
570 			uint64_t vss_offset = md->io.data_offset / FTL_BLOCK_SIZE;
571 			vss_offset *= FTL_MD_VSS_SZ;
572 			assert(md->io.md);
573 			memcpy(md->io.md, md->vss_data + vss_offset, FTL_MD_VSS_SZ * blocks);
574 			audit_md_vss_version(md, blocks);
575 		}
576 	}
577 #if defined(DEBUG)
578 	if (md->io.md && md->io.op == FTL_MD_OP_CLEAR) {
579 		uint64_t blocks = spdk_min(md->io.remaining, ftl_md_xfer_blocks(md->dev));
580 		audit_md_vss_version(md, blocks);
581 	}
582 #endif
583 
584 	read_write_blocks(md);
585 }
586 
587 static int
588 io_can_start(struct ftl_md *md)
589 {
590 	assert(NULL == md->io.data);
591 	if (NULL != md->io.data) {
592 		/* Outgoing IO on metadata */
593 		return -EINVAL;
594 	}
595 
596 	if (!md->region) {
597 		/* No device region to process data */
598 		return -EINVAL;
599 	}
600 
601 	if (md->region->current.blocks > md->data_blocks) {
602 		/* No device region to process data */
603 		FTL_ERRLOG(md->dev, "Blocks number mismatch between metadata object and"
604 			   "device region\n");
605 		return -EINVAL;
606 	}
607 
608 	return 0;
609 }
610 
611 static int
612 io_prepare(struct ftl_md *md, enum ftl_md_ops op)
613 {
614 	const struct ftl_layout_region *region = md->region;
615 	uint64_t data_size, meta_size = 0;
616 
617 	/* Allocates buffer for IO */
618 	data_size = xfer_size(md);
619 	md->io.data = spdk_zmalloc(data_size, FTL_BLOCK_SIZE, NULL,
620 				   SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
621 	if (!md->io.data) {
622 		return -ENOMEM;
623 	}
624 
625 	if (md->vss_data || md->region->vss_blksz) {
626 		meta_size = ftl_md_xfer_blocks(md->dev) * FTL_MD_VSS_SZ;
627 		md->io.md = spdk_zmalloc(meta_size, FTL_BLOCK_SIZE, NULL,
628 					 SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
629 		if (!md->io.md) {
630 			spdk_dma_free(md->io.data);
631 			md->io.data = NULL;
632 			return -ENOMEM;
633 		}
634 	}
635 
636 	md->io.address = region->current.offset;
637 	md->io.remaining = region->current.blocks;
638 	md->io.data_offset = 0;
639 	md->io.status = 0;
640 	md->io.op = op;
641 
642 	return 0;
643 }
644 
645 static int
646 io_init(struct ftl_md *md, enum ftl_md_ops op)
647 {
648 	if (io_can_start(md)) {
649 		return -EINVAL;
650 	}
651 
652 	if (io_prepare(md, op)) {
653 		return -ENOMEM;
654 	}
655 
656 	return 0;
657 }
658 
659 static uint64_t
660 persist_entry_lba(struct ftl_md *md, uint64_t start_entry)
661 {
662 	return md->region->current.offset + start_entry * md->region->entry_size;
663 }
664 
665 static void
666 persist_entry_cb(struct spdk_bdev_io *bdev_io, bool success, void *cb_arg)
667 {
668 	struct ftl_md_io_entry_ctx *ctx = cb_arg;
669 
670 	spdk_bdev_free_io(bdev_io);
671 
672 	assert(ctx->remaining > 0);
673 	ctx->remaining--;
674 
675 	if (!success) {
676 		ctx->status = -EIO;
677 	}
678 
679 	if (!ctx->remaining) {
680 		ctx->cb(ctx->status, ctx->cb_arg);
681 	}
682 }
683 
684 static int
685 ftl_md_persist_entry_write_blocks(struct ftl_md_io_entry_ctx *ctx, struct ftl_md *md,
686 				  spdk_bdev_io_wait_cb retry_fn)
687 {
688 	int rc;
689 
690 	rc = write_blocks(md->dev, md->region->bdev_desc, md->region->ioch,
691 			  ctx->buffer, ctx->vss_buffer,
692 			  persist_entry_lba(md, ctx->start_entry), md->region->entry_size,
693 			  persist_entry_cb, ctx);
694 	if (spdk_unlikely(rc)) {
695 		if (rc == -ENOMEM) {
696 			struct spdk_bdev *bdev = spdk_bdev_desc_get_bdev(md->region->bdev_desc);
697 			ctx->bdev_io_wait.bdev = bdev;
698 			ctx->bdev_io_wait.cb_fn = retry_fn;
699 			ctx->bdev_io_wait.cb_arg = ctx;
700 			spdk_bdev_queue_io_wait(bdev, md->region->ioch, &ctx->bdev_io_wait);
701 		} else {
702 			ftl_abort();
703 		}
704 	}
705 
706 	return rc;
707 }
708 
709 static void
710 ftl_md_persist_entry_mirror(void *_ctx)
711 {
712 	struct ftl_md_io_entry_ctx *ctx = _ctx;
713 
714 	ftl_md_persist_entry_write_blocks(ctx, ctx->md->mirror, ftl_md_persist_entry_mirror);
715 }
716 
717 static void
718 ftl_md_persist_entry_primary(void *_ctx)
719 {
720 	struct ftl_md_io_entry_ctx *ctx = _ctx;
721 	struct ftl_md *md = ctx->md;
722 	int rc;
723 
724 	rc = ftl_md_persist_entry_write_blocks(ctx, md, ftl_md_persist_entry_primary);
725 
726 	if (!rc && has_mirror(md)) {
727 		assert(md->region->entry_size == md->mirror->region->entry_size);
728 
729 		/* The MD object has mirror so execute persist on it too */
730 		ftl_md_persist_entry_mirror(ctx);
731 		ctx->remaining++;
732 	}
733 }
734 
735 static void
736 _ftl_md_persist_entry(struct ftl_md_io_entry_ctx *ctx)
737 {
738 	ctx->status = 0;
739 	ctx->remaining = 1;
740 
741 	/* First execute an IO to the primary region */
742 	ftl_md_persist_entry_primary(ctx);
743 }
744 
745 void
746 ftl_md_persist_entry(struct ftl_md *md, uint64_t start_entry, void *buffer, void *vss_buffer,
747 		     ftl_md_io_entry_cb cb, void *cb_arg,
748 		     struct ftl_md_io_entry_ctx *ctx)
749 {
750 	if (spdk_unlikely(0 == md->region->entry_size)) {
751 		/* This MD has not been configured to support persist entry call */
752 		ftl_abort();
753 	}
754 
755 	/* Initialize persist entry context */
756 	ctx->cb = cb;
757 	ctx->cb_arg = cb_arg;
758 	ctx->md = md;
759 	ctx->start_entry = start_entry;
760 	ctx->buffer = buffer;
761 	ctx->vss_buffer = vss_buffer ? : md->entry_vss_dma_buf;
762 
763 	_ftl_md_persist_entry(ctx);
764 }
765 
766 static void
767 read_entry_cb(struct spdk_bdev_io *bdev_io, bool success, void *cb_arg)
768 {
769 	struct ftl_md_io_entry_ctx *ctx = cb_arg;
770 	struct ftl_md *md = ctx->md;
771 
772 	spdk_bdev_free_io(bdev_io);
773 
774 	if (!success) {
775 		if (has_mirror(md)) {
776 			if (setup_mirror(md)) {
777 				/* An error when setup the mirror */
778 				ctx->status = -EIO;
779 				goto finish_io;
780 			}
781 
782 			/* First read from the mirror */
783 			ftl_md_read_entry(md->mirror, ctx->start_entry, ctx->buffer, ctx->vss_buffer,
784 					  ctx->cb, ctx->cb_arg,
785 					  ctx);
786 			return;
787 		} else {
788 			ctx->status = -EIO;
789 			goto finish_io;
790 		}
791 	}
792 
793 finish_io:
794 	ctx->cb(ctx->status, ctx->cb_arg);
795 }
796 
797 static void
798 ftl_md_read_entry_read_blocks(struct ftl_md_io_entry_ctx *ctx, struct ftl_md *md,
799 			      spdk_bdev_io_wait_cb retry_fn)
800 {
801 	int rc;
802 
803 	rc = read_blocks(md->dev, md->region->bdev_desc, md->region->ioch,
804 			 ctx->buffer, ctx->vss_buffer,
805 			 persist_entry_lba(md, ctx->start_entry), md->region->entry_size,
806 			 read_entry_cb, ctx);
807 
808 	if (spdk_unlikely(rc)) {
809 		if (rc == -ENOMEM) {
810 			struct spdk_bdev *bdev = spdk_bdev_desc_get_bdev(md->region->bdev_desc);
811 			ctx->bdev_io_wait.bdev = bdev;
812 			ctx->bdev_io_wait.cb_fn = retry_fn;
813 			ctx->bdev_io_wait.cb_arg = ctx;
814 			spdk_bdev_queue_io_wait(bdev, md->region->ioch, &ctx->bdev_io_wait);
815 		} else {
816 			ftl_abort();
817 		}
818 	}
819 }
820 
821 static void
822 _ftl_md_read_entry(void *_ctx)
823 {
824 	struct ftl_md_io_entry_ctx *ctx = _ctx;
825 
826 	ftl_md_read_entry_read_blocks(ctx, ctx->md, _ftl_md_read_entry);
827 }
828 
829 void
830 ftl_md_read_entry(struct ftl_md *md, uint64_t start_entry, void *buffer, void *vss_buffer,
831 		  ftl_md_io_entry_cb cb, void *cb_arg,
832 		  struct ftl_md_io_entry_ctx *ctx)
833 {
834 	if (spdk_unlikely(0 == md->region->entry_size)) {
835 		/* This MD has not been configured to support read entry call */
836 		ftl_abort();
837 	}
838 
839 	ctx->cb = cb;
840 	ctx->cb_arg = cb_arg;
841 	ctx->md = md;
842 	ctx->start_entry = start_entry;
843 	ctx->buffer = buffer;
844 	ctx->vss_buffer = vss_buffer;
845 
846 	_ftl_md_read_entry(ctx);
847 }
848 
849 void
850 ftl_md_persist_entry_retry(struct ftl_md_io_entry_ctx *ctx)
851 {
852 	_ftl_md_persist_entry(ctx);
853 }
854 
855 static void
856 persist_mirror_cb(struct spdk_ftl_dev *dev, struct ftl_md *md, int status)
857 {
858 	struct ftl_md *primary = md->owner.private;
859 
860 	if (status) {
861 		/* We got an error, stop persist procedure immediately */
862 		primary->io.status = status;
863 		io_done(primary);
864 	} else {
865 		/* Now continue the persist procedure on the primary MD object */
866 		if (0 == io_init(primary, FTL_MD_OP_PERSIST)) {
867 			io_submit(primary);
868 		} else {
869 			spdk_thread_send_msg(spdk_get_thread(), exception, primary);
870 		}
871 	}
872 }
873 
874 void
875 ftl_md_persist(struct ftl_md *md)
876 {
877 	if (has_mirror(md)) {
878 		if (setup_mirror(md)) {
879 			/* An error when setup the mirror */
880 			spdk_thread_send_msg(spdk_get_thread(), exception, md);
881 			return;
882 		}
883 
884 		/* Set callback and context in mirror */
885 		md->mirror->cb = persist_mirror_cb;
886 		md->mirror->owner.private = md;
887 
888 		/* First persist the mirror */
889 		ftl_md_persist(md->mirror);
890 		return;
891 	}
892 
893 	if (0 == io_init(md, FTL_MD_OP_PERSIST)) {
894 		io_submit(md);
895 	} else {
896 		spdk_thread_send_msg(spdk_get_thread(), exception, md);
897 	}
898 }
899 
900 static void
901 restore_mirror_cb(struct spdk_ftl_dev *dev, struct ftl_md *md, int status)
902 {
903 	struct ftl_md *primary = md->owner.private;
904 
905 	if (status) {
906 		/* Cannot restore the object from the mirror too, mark error and fail */
907 		primary->io.status = -EIO;
908 		io_done(primary);
909 	} else {
910 		/*
911 		 * Restoring from the mirror successful. Synchronize mirror to the primary.
912 		 * Because we read MD content from the mirror, we can disable it, only the primary
913 		 * requires persisting.
914 		 */
915 		primary->io.status = 0;
916 		primary->mirror_enabled = false;
917 		io_cleanup(primary);
918 		ftl_md_persist(primary);
919 		primary->mirror_enabled = true;
920 	}
921 }
922 
923 static void
924 restore_sync_cb(struct spdk_ftl_dev *dev, struct ftl_md *md, int status)
925 {
926 	struct ftl_md *primary = md->owner.private;
927 
928 	if (status) {
929 		/* Cannot sync the object from the primary to the mirror, mark error and fail */
930 		primary->io.status = -EIO;
931 		io_done(primary);
932 	} else {
933 		primary->cb(dev, primary, primary->io.status);
934 		io_cleanup(primary);
935 	}
936 }
937 
938 static int
939 restore_done(struct ftl_md *md)
940 {
941 	if (-EAGAIN == md->io.status) {
942 		/* Failed to read MD from primary region, try it from mirror.
943 		 * At the moment read the mirror entirely, (TODO) in the
944 		 * feature we can restore from primary and mirror region
945 		 * with finer granularity.
946 		 */
947 
948 		if (has_mirror(md)) {
949 			if (setup_mirror(md)) {
950 				/* An error when setup the mirror */
951 				return -EIO;
952 			}
953 
954 			/* Set callback and context in mirror */
955 			md->mirror->cb = restore_mirror_cb;
956 			md->mirror->owner.private = md;
957 
958 			/* First persist the mirror */
959 			ftl_md_restore(md->mirror);
960 			return -EAGAIN;
961 		} else {
962 			return -EIO;
963 		}
964 	} else if (0 == md->io.status && false == md->dev->sb->clean) {
965 		if (has_mirror(md)) {
966 			/* There was a dirty shutdown, synchronize primary to mirror */
967 
968 			/* Set callback and context in the mirror */
969 			md->mirror->cb = restore_sync_cb;
970 			md->mirror->owner.private = md;
971 
972 			/* First persist the mirror */
973 			ftl_md_persist(md->mirror);
974 			return -EAGAIN;
975 		}
976 	}
977 
978 	return md->io.status;
979 }
980 
981 static void
982 io_done(struct ftl_md *md)
983 {
984 	int status;
985 
986 	if (md->io.op == FTL_MD_OP_RESTORE) {
987 		status = restore_done(md);
988 	} else {
989 		status = md->io.status;
990 	}
991 
992 	if (status != -EAGAIN) {
993 		md->cb(md->dev, md, status);
994 		io_cleanup(md);
995 	}
996 }
997 
998 void
999 ftl_md_restore(struct ftl_md *md)
1000 {
1001 	if (0 == io_init(md, FTL_MD_OP_RESTORE)) {
1002 		io_submit(md);
1003 	} else {
1004 		spdk_thread_send_msg(spdk_get_thread(), exception, md);
1005 	}
1006 }
1007 
1008 static int
1009 pattern_prepare(struct ftl_md *md,
1010 		int data_pattern, union ftl_md_vss *vss_pattern)
1011 {
1012 	void *data = md->io.data;
1013 	uint64_t data_size = xfer_size(md);
1014 
1015 	memset(data, data_pattern, data_size);
1016 
1017 	if (md->io.md) {
1018 		if (vss_pattern) {
1019 			/* store the VSS pattern... */
1020 			ftl_md_vss_buf_init(md->io.md, ftl_md_xfer_blocks(md->dev), vss_pattern);
1021 		} else {
1022 			/* ...or default init VSS to 0 */
1023 			union ftl_md_vss vss = {0};
1024 
1025 			vss.version.md_version = md->region->current.version;
1026 			ftl_md_vss_buf_init(md->io.md, ftl_md_xfer_blocks(md->dev), &vss);
1027 		}
1028 	}
1029 
1030 	return 0;
1031 }
1032 
1033 static void
1034 clear_mirror_cb(struct spdk_ftl_dev *dev, struct ftl_md *secondary, int status)
1035 {
1036 	struct ftl_md *primary = secondary->owner.private;
1037 
1038 	if (status) {
1039 		/* We got an error, stop persist procedure immediately */
1040 		primary->io.status = status;
1041 		io_done(primary);
1042 	} else {
1043 		/* Now continue the persist procedure on the primary MD object */
1044 		if (0 == io_init(primary, FTL_MD_OP_CLEAR) &&
1045 		    0 == pattern_prepare(primary, *(int *)secondary->io.data,
1046 					 secondary->io.md)) {
1047 			io_submit(primary);
1048 		} else {
1049 			spdk_thread_send_msg(spdk_get_thread(), exception, primary);
1050 		}
1051 	}
1052 }
1053 
1054 void
1055 ftl_md_clear(struct ftl_md *md, int data_pattern, union ftl_md_vss *vss_pattern)
1056 {
1057 	if (has_mirror(md)) {
1058 		if (setup_mirror(md)) {
1059 			/* An error when setup the mirror */
1060 			spdk_thread_send_msg(spdk_get_thread(), exception, md);
1061 			return;
1062 		}
1063 
1064 		/* Set callback and context in mirror */
1065 		md->mirror->cb = clear_mirror_cb;
1066 		md->mirror->owner.private = md;
1067 
1068 		/* First persist the mirror */
1069 		ftl_md_clear(md->mirror, data_pattern, vss_pattern);
1070 		return;
1071 	}
1072 
1073 	if (0 == io_init(md, FTL_MD_OP_CLEAR) && 0 == pattern_prepare(md, data_pattern, vss_pattern)) {
1074 		io_submit(md);
1075 	} else {
1076 		spdk_thread_send_msg(spdk_get_thread(), exception, md);
1077 	}
1078 }
1079 
1080 const struct ftl_layout_region *
1081 ftl_md_get_region(struct ftl_md *md)
1082 {
1083 	return md->region;
1084 }
1085 
1086 int
1087 ftl_md_set_region(struct ftl_md *md,
1088 		  const struct ftl_layout_region *region)
1089 {
1090 	assert(region->current.blocks <= md->data_blocks);
1091 	md->region = region;
1092 
1093 	if (md->vss_data) {
1094 		union ftl_md_vss vss = {0};
1095 		vss.version.md_version = region->current.version;
1096 		ftl_md_vss_buf_init(md->vss_data, md->data_blocks, &vss);
1097 		if (region->entry_size) {
1098 			assert(md->entry_vss_dma_buf);
1099 			ftl_md_vss_buf_init(md->entry_vss_dma_buf, region->entry_size, &vss);
1100 		}
1101 	}
1102 
1103 	if (has_mirror(md)) {
1104 		return setup_mirror(md);
1105 	}
1106 
1107 	return 0;
1108 }
1109 
1110 int
1111 ftl_md_create_region_flags(struct spdk_ftl_dev *dev, int region_type)
1112 {
1113 	int flags = FTL_MD_CREATE_SHM;
1114 
1115 	switch (region_type) {
1116 	case FTL_LAYOUT_REGION_TYPE_SB:
1117 		if (dev->conf.mode & SPDK_FTL_MODE_CREATE) {
1118 			flags |= FTL_MD_CREATE_SHM_NEW;
1119 		}
1120 		break;
1121 
1122 	case FTL_LAYOUT_REGION_TYPE_BAND_MD:
1123 	case FTL_LAYOUT_REGION_TYPE_NVC_MD:
1124 		if (!ftl_fast_startup(dev)) {
1125 			flags |= FTL_MD_CREATE_SHM_NEW;
1126 		}
1127 		break;
1128 	case FTL_LAYOUT_REGION_TYPE_VALID_MAP:
1129 		if (!ftl_fast_startup(dev) && !ftl_fast_recovery(dev)) {
1130 			flags |= FTL_MD_CREATE_SHM_NEW;
1131 		}
1132 		break;
1133 	default:
1134 		return FTL_MD_CREATE_HEAP;
1135 	}
1136 
1137 	return flags;
1138 }
1139 
1140 int
1141 ftl_md_destroy_region_flags(struct spdk_ftl_dev *dev, int region_type)
1142 {
1143 	switch (region_type) {
1144 	case FTL_LAYOUT_REGION_TYPE_SB:
1145 	case FTL_LAYOUT_REGION_TYPE_BAND_MD:
1146 	case FTL_LAYOUT_REGION_TYPE_VALID_MAP:
1147 	case FTL_LAYOUT_REGION_TYPE_NVC_MD:
1148 		if (dev->conf.fast_shutdown) {
1149 			return FTL_MD_DESTROY_SHM_KEEP;
1150 		}
1151 		break;
1152 
1153 	default:
1154 		break;
1155 	}
1156 	return 0;
1157 }
1158 
1159 int
1160 ftl_md_create_shm_flags(struct spdk_ftl_dev *dev)
1161 {
1162 	int flags = FTL_MD_CREATE_SHM;
1163 
1164 	if (!ftl_fast_startup(dev) && !ftl_fast_recovery(dev)) {
1165 		flags |= FTL_MD_CREATE_SHM_NEW;
1166 	}
1167 	return flags;
1168 }
1169 
1170 int
1171 ftl_md_destroy_shm_flags(struct spdk_ftl_dev *dev)
1172 {
1173 	return (dev->conf.fast_shutdown) ? FTL_MD_DESTROY_SHM_KEEP : 0;
1174 }
1175