xref: /spdk/lib/blob/blobstore.h (revision 22898a91b9b6f289933db19b0175821cfb7e7820)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (c) Intel Corporation.
5  *   All rights reserved.
6  *
7  *   Redistribution and use in source and binary forms, with or without
8  *   modification, are permitted provided that the following conditions
9  *   are met:
10  *
11  *     * Redistributions of source code must retain the above copyright
12  *       notice, this list of conditions and the following disclaimer.
13  *     * Redistributions in binary form must reproduce the above copyright
14  *       notice, this list of conditions and the following disclaimer in
15  *       the documentation and/or other materials provided with the
16  *       distribution.
17  *     * Neither the name of Intel Corporation nor the names of its
18  *       contributors may be used to endorse or promote products derived
19  *       from this software without specific prior written permission.
20  *
21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #ifndef SPDK_BLOBSTORE_H
35 #define SPDK_BLOBSTORE_H
36 
37 #include "spdk/assert.h"
38 #include "spdk/blob.h"
39 #include "spdk/queue.h"
40 #include "spdk/util.h"
41 
42 #include "request.h"
43 
44 /* In Memory Data Structures
45  *
46  * The following data structures exist only in memory.
47  */
48 
49 #define SPDK_BLOB_OPTS_CLUSTER_SZ (1024 * 1024)
50 #define SPDK_BLOB_OPTS_NUM_MD_PAGES UINT32_MAX
51 #define SPDK_BLOB_OPTS_MAX_MD_OPS 32
52 #define SPDK_BLOB_OPTS_DEFAULT_CHANNEL_OPS 512
53 #define SPDK_BLOB_BLOBID_HIGH_BIT (1ULL << 32)
54 
55 struct spdk_xattr {
56 	/* TODO: reorder for best packing */
57 	uint32_t	index;
58 	char		*name;
59 	void		*value;
60 	uint16_t	value_len;
61 	TAILQ_ENTRY(spdk_xattr)	link;
62 };
63 
64 /* The mutable part of the blob data that is sync'd to
65  * disk. The data in here is both mutable and persistent.
66  */
67 struct spdk_blob_mut_data {
68 	/* Number of data clusters in the blob */
69 	uint64_t	num_clusters;
70 
71 	/* Array LBAs that are the beginning of a cluster, in
72 	 * the order they appear in the blob.
73 	 */
74 	uint64_t	*clusters;
75 
76 	/* The size of the clusters array. This is greater than or
77 	 * equal to 'num_clusters'.
78 	 */
79 	size_t		cluster_array_size;
80 
81 	/* Number of metadata pages */
82 	uint32_t	num_pages;
83 
84 	/* Array of page offsets into the metadata region, in
85 	 * the order of the metadata page sequence.
86 	 */
87 	uint32_t	*pages;
88 };
89 
90 enum spdk_blob_state {
91 	/* The blob in-memory version does not match the on-disk
92 	 * version.
93 	 */
94 	SPDK_BLOB_STATE_DIRTY,
95 
96 	/* The blob in memory version of the blob matches the on disk
97 	 * version.
98 	 */
99 	SPDK_BLOB_STATE_CLEAN,
100 
101 	/* The in-memory state being synchronized with the on-disk
102 	 * blob state. */
103 	SPDK_BLOB_STATE_LOADING,
104 };
105 
106 TAILQ_HEAD(spdk_xattr_tailq, spdk_xattr);
107 
108 struct spdk_blob_list {
109 	spdk_blob_id id;
110 	size_t clone_count;
111 	TAILQ_HEAD(, spdk_blob_list) clones;
112 	TAILQ_ENTRY(spdk_blob_list) link;
113 };
114 
115 struct spdk_blob {
116 	struct spdk_blob_store *bs;
117 
118 	uint32_t	open_ref;
119 
120 	spdk_blob_id	id;
121 	spdk_blob_id	parent_id;
122 
123 	enum spdk_blob_state		state;
124 
125 	/* Two copies of the mutable data. One is a version
126 	 * that matches the last known data on disk (clean).
127 	 * The other (active) is the current data. Syncing
128 	 * a blob makes the clean match the active.
129 	 */
130 	struct spdk_blob_mut_data	clean;
131 	struct spdk_blob_mut_data	active;
132 
133 	bool		invalid;
134 	bool		data_ro;
135 	bool		md_ro;
136 
137 	uint64_t	invalid_flags;
138 	uint64_t	data_ro_flags;
139 	uint64_t	md_ro_flags;
140 
141 	struct spdk_bs_dev *back_bs_dev;
142 
143 	/* TODO: The xattrs are mutable, but we don't want to be
144 	 * copying them unecessarily. Figure this out.
145 	 */
146 	struct spdk_xattr_tailq xattrs;
147 	struct spdk_xattr_tailq xattrs_internal;
148 
149 	TAILQ_ENTRY(spdk_blob) link;
150 };
151 
152 struct spdk_blob_store {
153 	uint64_t			md_start; /* Offset from beginning of disk, in pages */
154 	uint32_t			md_len; /* Count, in pages */
155 
156 	struct spdk_io_channel		*md_channel;
157 	uint32_t			max_channel_ops;
158 
159 	struct spdk_thread		*md_thread;
160 
161 	struct spdk_bs_dev		*dev;
162 
163 	struct spdk_bit_array		*used_md_pages;
164 	struct spdk_bit_array		*used_clusters;
165 	struct spdk_bit_array		*used_blobids;
166 
167 	pthread_mutex_t			used_clusters_mutex;
168 
169 	uint32_t			cluster_sz;
170 	uint64_t			total_clusters;
171 	uint64_t			total_data_clusters;
172 	uint64_t			num_free_clusters;
173 	uint32_t			pages_per_cluster;
174 
175 	spdk_blob_id			super_blob;
176 	struct spdk_bs_type		bstype;
177 
178 	struct spdk_bs_cpl		unload_cpl;
179 	int				unload_err;
180 
181 	TAILQ_HEAD(, spdk_blob)		blobs;
182 	TAILQ_HEAD(, spdk_blob_list)	snapshots;
183 };
184 
185 struct spdk_bs_channel {
186 	struct spdk_bs_request_set	*req_mem;
187 	TAILQ_HEAD(, spdk_bs_request_set) reqs;
188 
189 	struct spdk_blob_store		*bs;
190 
191 	struct spdk_bs_dev		*dev;
192 	struct spdk_io_channel		*dev_channel;
193 
194 	TAILQ_HEAD(, spdk_bs_request_set) need_cluster_alloc;
195 };
196 
197 /** operation type */
198 enum spdk_blob_op_type {
199 	SPDK_BLOB_WRITE,
200 	SPDK_BLOB_READ,
201 	SPDK_BLOB_UNMAP,
202 	SPDK_BLOB_WRITE_ZEROES,
203 	SPDK_BLOB_WRITEV,
204 	SPDK_BLOB_READV,
205 };
206 
207 /* back bs_dev */
208 
209 #define BLOB_SNAPSHOT "SNAP"
210 #define SNAPSHOT_IN_PROGRESS "SNAPTMP"
211 
212 struct spdk_blob_bs_dev {
213 	struct spdk_bs_dev bs_dev;
214 	struct spdk_blob *blob;
215 };
216 
217 /* On-Disk Data Structures
218  *
219  * The following data structures exist on disk.
220  */
221 #define SPDK_BS_INITIAL_VERSION 1
222 #define SPDK_BS_VERSION 3 /* current version */
223 
224 #pragma pack(push, 1)
225 
226 #define SPDK_MD_MASK_TYPE_USED_PAGES 0
227 #define SPDK_MD_MASK_TYPE_USED_CLUSTERS 1
228 #define SPDK_MD_MASK_TYPE_USED_BLOBIDS 2
229 
230 struct spdk_bs_md_mask {
231 	uint8_t		type;
232 	uint32_t	length; /* In bits */
233 	uint8_t		mask[0];
234 };
235 
236 #define SPDK_MD_DESCRIPTOR_TYPE_PADDING 0
237 #define SPDK_MD_DESCRIPTOR_TYPE_EXTENT 1
238 #define SPDK_MD_DESCRIPTOR_TYPE_XATTR 2
239 #define SPDK_MD_DESCRIPTOR_TYPE_FLAGS 3
240 #define SPDK_MD_DESCRIPTOR_TYPE_XATTR_INTERNAL 4
241 
242 struct spdk_blob_md_descriptor_xattr {
243 	uint8_t		type;
244 	uint32_t	length;
245 
246 	uint16_t	name_length;
247 	uint16_t	value_length;
248 
249 	char		name[0];
250 	/* String name immediately followed by string value. */
251 };
252 
253 struct spdk_blob_md_descriptor_extent {
254 	uint8_t		type;
255 	uint32_t	length;
256 
257 	struct {
258 		uint32_t        cluster_idx;
259 		uint32_t        length; /* In units of clusters */
260 	} extents[0];
261 };
262 
263 #define SPDK_BLOB_THIN_PROV (1ULL << 0)
264 #define SPDK_BLOB_INTERNAL_XATTR (1ULL << 1)
265 #define SPDK_BLOB_INVALID_FLAGS_MASK	(SPDK_BLOB_THIN_PROV | SPDK_BLOB_INTERNAL_XATTR)
266 
267 #define SPDK_BLOB_READ_ONLY (1ULL << 0)
268 #define SPDK_BLOB_DATA_RO_FLAGS_MASK	SPDK_BLOB_READ_ONLY
269 #define SPDK_BLOB_MD_RO_FLAGS_MASK	0
270 
271 struct spdk_blob_md_descriptor_flags {
272 	uint8_t		type;
273 	uint32_t	length;
274 
275 	/*
276 	 * If a flag in invalid_flags is set that the application is not aware of,
277 	 *  it will not allow the blob to be opened.
278 	 */
279 	uint64_t	invalid_flags;
280 
281 	/*
282 	 * If a flag in data_ro_flags is set that the application is not aware of,
283 	 *  allow the blob to be opened in data_read_only and md_read_only mode.
284 	 */
285 	uint64_t	data_ro_flags;
286 
287 	/*
288 	 * If a flag in md_ro_flags is set the the application is not aware of,
289 	 *  allow the blob to be opened in md_read_only mode.
290 	 */
291 	uint64_t	md_ro_flags;
292 };
293 
294 struct spdk_blob_md_descriptor {
295 	uint8_t		type;
296 	uint32_t	length;
297 };
298 
299 #define SPDK_INVALID_MD_PAGE UINT32_MAX
300 
301 struct spdk_blob_md_page {
302 	spdk_blob_id     id;
303 
304 	uint32_t        sequence_num;
305 	uint32_t	reserved0;
306 
307 	/* Descriptors here */
308 	uint8_t		descriptors[4072];
309 
310 	uint32_t	next;
311 	uint32_t	crc;
312 };
313 #define SPDK_BS_PAGE_SIZE 0x1000
314 SPDK_STATIC_ASSERT(SPDK_BS_PAGE_SIZE == sizeof(struct spdk_blob_md_page), "Invalid md page size");
315 
316 #define SPDK_BS_SUPER_BLOCK_SIG "SPDKBLOB"
317 
318 struct spdk_bs_super_block {
319 	uint8_t		signature[8];
320 	uint32_t        version;
321 	uint32_t        length;
322 	uint32_t	clean; /* If there was a clean shutdown, this is 1. */
323 	spdk_blob_id	super_blob;
324 
325 	uint32_t	cluster_size; /* In bytes */
326 
327 	uint32_t	used_page_mask_start; /* Offset from beginning of disk, in pages */
328 	uint32_t	used_page_mask_len; /* Count, in pages */
329 
330 	uint32_t	used_cluster_mask_start; /* Offset from beginning of disk, in pages */
331 	uint32_t	used_cluster_mask_len; /* Count, in pages */
332 
333 	uint32_t	md_start; /* Offset from beginning of disk, in pages */
334 	uint32_t	md_len; /* Count, in pages */
335 
336 	struct spdk_bs_type	bstype; /* blobstore type */
337 
338 	uint32_t	used_blobid_mask_start; /* Offset from beginning of disk, in pages */
339 	uint32_t	used_blobid_mask_len; /* Count, in pages */
340 
341 	uint8_t		reserved[4012];
342 	uint32_t	crc;
343 };
344 SPDK_STATIC_ASSERT(sizeof(struct spdk_bs_super_block) == 0x1000, "Invalid super block size");
345 
346 #pragma pack(pop)
347 
348 struct spdk_bs_dev *spdk_bs_create_zeroes_dev(void);
349 struct spdk_bs_dev *spdk_bs_create_blob_bs_dev(struct spdk_blob *blob);
350 
351 /* Unit Conversions
352  *
353  * The blobstore works with several different units:
354  * - Byte: Self explanatory
355  * - LBA: The logical blocks on the backing storage device.
356  * - Page: The read/write units of blobs and metadata. This is
357  *         an offset into a blob in units of 4KiB.
358  * - Cluster Index: The disk is broken into a sequential list of
359  *		    clusters. This is the offset from the beginning.
360  *
361  * NOTE: These conversions all act on simple magnitudes, not with any sort
362  *        of knowledge about the blobs themselves. For instance, converting
363  *        a page to an lba with the conversion function below simply converts
364  *        a number of pages to an equivalent number of lbas, but that
365  *        lba certainly isn't the right lba that corresponds to a page offset
366  *        for a particular blob.
367  */
368 static inline uint64_t
369 _spdk_bs_byte_to_lba(struct spdk_blob_store *bs, uint64_t length)
370 {
371 	assert(length % bs->dev->blocklen == 0);
372 
373 	return length / bs->dev->blocklen;
374 }
375 
376 static inline uint64_t
377 _spdk_bs_dev_byte_to_lba(struct spdk_bs_dev *bs_dev, uint64_t length)
378 {
379 	assert(length % bs_dev->blocklen == 0);
380 
381 	return length / bs_dev->blocklen;
382 }
383 
384 static inline uint64_t
385 _spdk_bs_lba_to_byte(struct spdk_blob_store *bs, uint64_t lba)
386 {
387 	return lba * bs->dev->blocklen;
388 }
389 
390 static inline uint64_t
391 _spdk_bs_page_to_lba(struct spdk_blob_store *bs, uint64_t page)
392 {
393 	return page * SPDK_BS_PAGE_SIZE / bs->dev->blocklen;
394 }
395 
396 static inline uint64_t
397 _spdk_bs_dev_page_to_lba(struct spdk_bs_dev *bs_dev, uint64_t page)
398 {
399 	return page * SPDK_BS_PAGE_SIZE / bs_dev->blocklen;
400 }
401 
402 static inline uint32_t
403 _spdk_bs_lba_to_page(struct spdk_blob_store *bs, uint64_t lba)
404 {
405 	uint64_t	lbas_per_page;
406 
407 	lbas_per_page = SPDK_BS_PAGE_SIZE / bs->dev->blocklen;
408 
409 	assert(lba % lbas_per_page == 0);
410 
411 	return lba / lbas_per_page;
412 }
413 
414 static inline uint64_t
415 _spdk_bs_dev_lba_to_page(struct spdk_bs_dev *bs_dev, uint64_t lba)
416 {
417 	uint64_t	lbas_per_page;
418 
419 	lbas_per_page = SPDK_BS_PAGE_SIZE / bs_dev->blocklen;
420 
421 	assert(lba % lbas_per_page == 0);
422 
423 	return lba / lbas_per_page;
424 }
425 
426 static inline uint64_t
427 _spdk_bs_cluster_to_page(struct spdk_blob_store *bs, uint32_t cluster)
428 {
429 	return cluster * bs->pages_per_cluster;
430 }
431 
432 static inline uint32_t
433 _spdk_bs_page_to_cluster(struct spdk_blob_store *bs, uint64_t page)
434 {
435 	assert(page % bs->pages_per_cluster == 0);
436 
437 	return page / bs->pages_per_cluster;
438 }
439 
440 static inline uint64_t
441 _spdk_bs_cluster_to_lba(struct spdk_blob_store *bs, uint32_t cluster)
442 {
443 	return cluster * (bs->cluster_sz / bs->dev->blocklen);
444 }
445 
446 static inline uint32_t
447 _spdk_bs_lba_to_cluster(struct spdk_blob_store *bs, uint64_t lba)
448 {
449 	assert(lba % (bs->cluster_sz / bs->dev->blocklen) == 0);
450 
451 	return lba / (bs->cluster_sz / bs->dev->blocklen);
452 }
453 
454 static inline uint64_t
455 _spdk_bs_blob_lba_to_back_dev_lba(struct spdk_blob *blob, uint64_t lba)
456 {
457 	return lba * blob->bs->dev->blocklen / blob->back_bs_dev->blocklen;
458 }
459 
460 static inline uint64_t
461 _spdk_bs_blob_lba_from_back_dev_lba(struct spdk_blob *blob, uint64_t lba)
462 {
463 	return lba * blob->back_bs_dev->blocklen / blob->bs->dev->blocklen;
464 }
465 
466 /* End basic conversions */
467 
468 static inline uint32_t
469 _spdk_bs_blobid_to_page(spdk_blob_id id)
470 {
471 	return id & 0xFFFFFFFF;
472 }
473 
474 /* The blob id is a 64 bit number. The lower 32 bits are the page_idx. The upper
475  * 32 bits are not currently used. Stick a 1 there just to catch bugs where the
476  * code assumes blob id == page_idx.
477  */
478 static inline spdk_blob_id
479 _spdk_bs_page_to_blobid(uint32_t page_idx)
480 {
481 	return SPDK_BLOB_BLOBID_HIGH_BIT | page_idx;
482 }
483 
484 /* Given a page offset into a blob, look up the LBA for the
485  * start of that page.
486  */
487 static inline uint64_t
488 _spdk_bs_blob_page_to_lba(struct spdk_blob *blob, uint32_t page)
489 {
490 	uint64_t	lba;
491 	uint32_t	pages_per_cluster;
492 
493 	pages_per_cluster = blob->bs->pages_per_cluster;
494 
495 	assert(page < blob->active.num_clusters * pages_per_cluster);
496 
497 	lba = blob->active.clusters[page / pages_per_cluster];
498 	lba += _spdk_bs_page_to_lba(blob->bs, page % pages_per_cluster);
499 
500 	return lba;
501 }
502 
503 /* Given a page offset into a blob, look up the number of pages until the
504  * next cluster boundary.
505  */
506 static inline uint32_t
507 _spdk_bs_num_pages_to_cluster_boundary(struct spdk_blob *blob, uint32_t page)
508 {
509 	uint32_t	pages_per_cluster;
510 
511 	pages_per_cluster = blob->bs->pages_per_cluster;
512 
513 	return pages_per_cluster - (page % pages_per_cluster);
514 }
515 
516 /* Given a page offset into a blob, look up the number of pages into blob to beginning of current cluster */
517 static inline uint32_t
518 _spdk_bs_page_to_cluster_start(struct spdk_blob *blob, uint32_t page)
519 {
520 	uint32_t	pages_per_cluster;
521 
522 	pages_per_cluster = blob->bs->pages_per_cluster;
523 
524 	return page - (page % pages_per_cluster);
525 }
526 
527 /* Given a page offset into a blob, look up if it is from allocated cluster. */
528 static inline bool
529 _spdk_bs_page_is_allocated(struct spdk_blob *blob, uint32_t page)
530 {
531 	uint64_t	lba;
532 	uint32_t	pages_per_cluster;
533 
534 	pages_per_cluster = blob->bs->pages_per_cluster;
535 
536 	assert(page < blob->active.num_clusters * pages_per_cluster);
537 
538 	lba = blob->active.clusters[page / pages_per_cluster];
539 
540 	if (lba == 0) {
541 		assert(spdk_blob_is_thin_provisioned(blob));
542 		return false;
543 	} else {
544 		return true;
545 	}
546 }
547 
548 #endif
549