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bcache: move uapi header bcache.h to bcache code directory

The header file include/uapi/linux/bcache.h is not really a user space API heaer. This file defines the ondisk format of bcache internal meta data but no one includes it from user space, bcache-tools has its own copy of this header with minor modification. Therefore, this patch moves include/uapi/linux/bcache.h to bcache code directory as drivers/md/bcache/bcache_ondisk.h.

Coly Li committed 5 years ago

Commit cf2197c1 parent ca778795 files · +5 −4Browse files

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include/uapi/linux/bcache.h+0−445
@@ -1,445 +0,0 @@
1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2#ifndef _LINUX_BCACHE_H
3#define _LINUX_BCACHE_H
4
5/*
6 * Bcache on disk data structures
7 */
8
9#include <linux/types.h>
10
11#define BITMASK(name, type, field, offset, size) \
12static inline __u64 name(const type *k) \
13{ return (k->field >> offset) & ~(~0ULL << size); } \
14 \
15static inline void SET_##name(type *k, __u64 v) \
16{ \
17 k->field &= ~(~(~0ULL << size) << offset); \
18 k->field |= (v & ~(~0ULL << size)) << offset; \
19}
20
21/* Btree keys - all units are in sectors */
22
23struct bkey {
24 __u64 high;
25 __u64 low;
26 __u64 ptr[];
27};
28
29#define KEY_FIELD(name, field, offset, size) \
30 BITMASK(name, struct bkey, field, offset, size)
31
32#define PTR_FIELD(name, offset, size) \
33static inline __u64 name(const struct bkey *k, unsigned int i) \
34{ return (k->ptr[i] >> offset) & ~(~0ULL << size); } \
35 \
36static inline void SET_##name(struct bkey *k, unsigned int i, __u64 v) \
37{ \
38 k->ptr[i] &= ~(~(~0ULL << size) << offset); \
39 k->ptr[i] |= (v & ~(~0ULL << size)) << offset; \
40}
41
42#define KEY_SIZE_BITS 16
43#define KEY_MAX_U64S 8
44
45KEY_FIELD(KEY_PTRS, high, 60, 3)
46KEY_FIELD(__PAD0, high, 58, 2)
47KEY_FIELD(KEY_CSUM, high, 56, 2)
48KEY_FIELD(__PAD1, high, 55, 1)
49KEY_FIELD(KEY_DIRTY, high, 36, 1)
50
51KEY_FIELD(KEY_SIZE, high, 20, KEY_SIZE_BITS)
52KEY_FIELD(KEY_INODE, high, 0, 20)
53
54/* Next time I change the on disk format, KEY_OFFSET() won't be 64 bits */
55
56static inline __u64 KEY_OFFSET(const struct bkey *k)
57{
58 return k->low;
59}
60
61static inline void SET_KEY_OFFSET(struct bkey *k, __u64 v)
62{
63 k->low = v;
64}
65
66/*
67 * The high bit being set is a relic from when we used it to do binary
68 * searches - it told you where a key started. It's not used anymore,
69 * and can probably be safely dropped.
70 */
71#define KEY(inode, offset, size) \
72((struct bkey) { \
73 .high = (1ULL << 63) | ((__u64) (size) << 20) | (inode), \
74 .low = (offset) \
75})
76
77#define ZERO_KEY KEY(0, 0, 0)
78
79#define MAX_KEY_INODE (~(~0 << 20))
80#define MAX_KEY_OFFSET (~0ULL >> 1)
81#define MAX_KEY KEY(MAX_KEY_INODE, MAX_KEY_OFFSET, 0)
82
83#define KEY_START(k) (KEY_OFFSET(k) - KEY_SIZE(k))
84#define START_KEY(k) KEY(KEY_INODE(k), KEY_START(k), 0)
85
86#define PTR_DEV_BITS 12
87
88PTR_FIELD(PTR_DEV, 51, PTR_DEV_BITS)
89PTR_FIELD(PTR_OFFSET, 8, 43)
90PTR_FIELD(PTR_GEN, 0, 8)
91
92#define PTR_CHECK_DEV ((1 << PTR_DEV_BITS) - 1)
93
94#define MAKE_PTR(gen, offset, dev) \
95 ((((__u64) dev) << 51) | ((__u64) offset) << 8 | gen)
96
97/* Bkey utility code */
98
99static inline unsigned long bkey_u64s(const struct bkey *k)
100{
101 return (sizeof(struct bkey) / sizeof(__u64)) + KEY_PTRS(k);
102}
103
104static inline unsigned long bkey_bytes(const struct bkey *k)
105{
106 return bkey_u64s(k) * sizeof(__u64);
107}
108
109#define bkey_copy(_dest, _src) memcpy(_dest, _src, bkey_bytes(_src))
110
111static inline void bkey_copy_key(struct bkey *dest, const struct bkey *src)
112{
113 SET_KEY_INODE(dest, KEY_INODE(src));
114 SET_KEY_OFFSET(dest, KEY_OFFSET(src));
115}
116
117static inline struct bkey *bkey_next(const struct bkey *k)
118{
119 __u64 *d = (void *) k;
120
121 return (struct bkey *) (d + bkey_u64s(k));
122}
123
124static inline struct bkey *bkey_idx(const struct bkey *k, unsigned int nr_keys)
125{
126 __u64 *d = (void *) k;
127
128 return (struct bkey *) (d + nr_keys);
129}
130/* Enough for a key with 6 pointers */
131#define BKEY_PAD 8
132
133#define BKEY_PADDED(key) \
134 union { struct bkey key; __u64 key ## _pad[BKEY_PAD]; }
135
136/* Superblock */
137
138/* Version 0: Cache device
139 * Version 1: Backing device
140 * Version 2: Seed pointer into btree node checksum
141 * Version 3: Cache device with new UUID format
142 * Version 4: Backing device with data offset
143 */
144#define BCACHE_SB_VERSION_CDEV 0
145#define BCACHE_SB_VERSION_BDEV 1
146#define BCACHE_SB_VERSION_CDEV_WITH_UUID 3
147#define BCACHE_SB_VERSION_BDEV_WITH_OFFSET 4
148#define BCACHE_SB_VERSION_CDEV_WITH_FEATURES 5
149#define BCACHE_SB_VERSION_BDEV_WITH_FEATURES 6
150#define BCACHE_SB_MAX_VERSION 6
151
152#define SB_SECTOR 8
153#define SB_OFFSET (SB_SECTOR << SECTOR_SHIFT)
154#define SB_SIZE 4096
155#define SB_LABEL_SIZE 32
156#define SB_JOURNAL_BUCKETS 256U
157/* SB_JOURNAL_BUCKETS must be divisible by BITS_PER_LONG */
158#define MAX_CACHES_PER_SET 8
159
160#define BDEV_DATA_START_DEFAULT 16 /* sectors */
161
162struct cache_sb_disk {
163 __le64 csum;
164 __le64 offset; /* sector where this sb was written */
165 __le64 version;
166
167 __u8 magic[16];
168
169 __u8 uuid[16];
170 union {
171 __u8 set_uuid[16];
172 __le64 set_magic;
173 };
174 __u8 label[SB_LABEL_SIZE];
175
176 __le64 flags;
177 __le64 seq;
178
179 __le64 feature_compat;
180 __le64 feature_incompat;
181 __le64 feature_ro_compat;
182
183 __le64 pad[5];
184
185 union {
186 struct {
187 /* Cache devices */
188 __le64 nbuckets; /* device size */
189
190 __le16 block_size; /* sectors */
191 __le16 bucket_size; /* sectors */
192
193 __le16 nr_in_set;
194 __le16 nr_this_dev;
195 };
196 struct {
197 /* Backing devices */
198 __le64 data_offset;
199
200 /*
201 * block_size from the cache device section is still used by
202 * backing devices, so don't add anything here until we fix
203 * things to not need it for backing devices anymore
204 */
205 };
206 };
207
208 __le32 last_mount; /* time overflow in y2106 */
209
210 __le16 first_bucket;
211 union {
212 __le16 njournal_buckets;
213 __le16 keys;
214 };
215 __le64 d[SB_JOURNAL_BUCKETS]; /* journal buckets */
216 __le16 obso_bucket_size_hi; /* obsoleted */
217};
218
219/*
220 * This is for in-memory bcache super block.
221 * NOTE: cache_sb is NOT exactly mapping to cache_sb_disk, the member
222 * size, ordering and even whole struct size may be different
223 * from cache_sb_disk.
224 */
225struct cache_sb {
226 __u64 offset; /* sector where this sb was written */
227 __u64 version;
228
229 __u8 magic[16];
230
231 __u8 uuid[16];
232 union {
233 __u8 set_uuid[16];
234 __u64 set_magic;
235 };
236 __u8 label[SB_LABEL_SIZE];
237
238 __u64 flags;
239 __u64 seq;
240
241 __u64 feature_compat;
242 __u64 feature_incompat;
243 __u64 feature_ro_compat;
244
245 union {
246 struct {
247 /* Cache devices */
248 __u64 nbuckets; /* device size */
249
250 __u16 block_size; /* sectors */
251 __u16 nr_in_set;
252 __u16 nr_this_dev;
253 __u32 bucket_size; /* sectors */
254 };
255 struct {
256 /* Backing devices */
257 __u64 data_offset;
258
259 /*
260 * block_size from the cache device section is still used by
261 * backing devices, so don't add anything here until we fix
262 * things to not need it for backing devices anymore
263 */
264 };
265 };
266
267 __u32 last_mount; /* time overflow in y2106 */
268
269 __u16 first_bucket;
270 union {
271 __u16 njournal_buckets;
272 __u16 keys;
273 };
274 __u64 d[SB_JOURNAL_BUCKETS]; /* journal buckets */
275};
276
277static inline _Bool SB_IS_BDEV(const struct cache_sb *sb)
278{
279 return sb->version == BCACHE_SB_VERSION_BDEV
280 || sb->version == BCACHE_SB_VERSION_BDEV_WITH_OFFSET
281 || sb->version == BCACHE_SB_VERSION_BDEV_WITH_FEATURES;
282}
283
284BITMASK(CACHE_SYNC, struct cache_sb, flags, 0, 1);
285BITMASK(CACHE_DISCARD, struct cache_sb, flags, 1, 1);
286BITMASK(CACHE_REPLACEMENT, struct cache_sb, flags, 2, 3);
287#define CACHE_REPLACEMENT_LRU 0U
288#define CACHE_REPLACEMENT_FIFO 1U
289#define CACHE_REPLACEMENT_RANDOM 2U
290
291BITMASK(BDEV_CACHE_MODE, struct cache_sb, flags, 0, 4);
292#define CACHE_MODE_WRITETHROUGH 0U
293#define CACHE_MODE_WRITEBACK 1U
294#define CACHE_MODE_WRITEAROUND 2U
295#define CACHE_MODE_NONE 3U
296BITMASK(BDEV_STATE, struct cache_sb, flags, 61, 2);
297#define BDEV_STATE_NONE 0U
298#define BDEV_STATE_CLEAN 1U
299#define BDEV_STATE_DIRTY 2U
300#define BDEV_STATE_STALE 3U
301
302/*
303 * Magic numbers
304 *
305 * The various other data structures have their own magic numbers, which are
306 * xored with the first part of the cache set's UUID
307 */
308
309#define JSET_MAGIC 0x245235c1a3625032ULL
310#define PSET_MAGIC 0x6750e15f87337f91ULL
311#define BSET_MAGIC 0x90135c78b99e07f5ULL
312
313static inline __u64 jset_magic(struct cache_sb *sb)
314{
315 return sb->set_magic ^ JSET_MAGIC;
316}
317
318static inline __u64 pset_magic(struct cache_sb *sb)
319{
320 return sb->set_magic ^ PSET_MAGIC;
321}
322
323static inline __u64 bset_magic(struct cache_sb *sb)
324{
325 return sb->set_magic ^ BSET_MAGIC;
326}
327
328/*
329 * Journal
330 *
331 * On disk format for a journal entry:
332 * seq is monotonically increasing; every journal entry has its own unique
333 * sequence number.
334 *
335 * last_seq is the oldest journal entry that still has keys the btree hasn't
336 * flushed to disk yet.
337 *
338 * version is for on disk format changes.
339 */
340
341#define BCACHE_JSET_VERSION_UUIDv1 1
342#define BCACHE_JSET_VERSION_UUID 1 /* Always latest UUID format */
343#define BCACHE_JSET_VERSION 1
344
345struct jset {
346 __u64 csum;
347 __u64 magic;
348 __u64 seq;
349 __u32 version;
350 __u32 keys;
351
352 __u64 last_seq;
353
354 BKEY_PADDED(uuid_bucket);
355 BKEY_PADDED(btree_root);
356 __u16 btree_level;
357 __u16 pad[3];
358
359 __u64 prio_bucket[MAX_CACHES_PER_SET];
360
361 union {
362 struct bkey start[0];
363 __u64 d[0];
364 };
365};
366
367/* Bucket prios/gens */
368
369struct prio_set {
370 __u64 csum;
371 __u64 magic;
372 __u64 seq;
373 __u32 version;
374 __u32 pad;
375
376 __u64 next_bucket;
377
378 struct bucket_disk {
379 __u16 prio;
380 __u8 gen;
381 } __attribute((packed)) data[];
382};
383
384/* UUIDS - per backing device/flash only volume metadata */
385
386struct uuid_entry {
387 union {
388 struct {
389 __u8 uuid[16];
390 __u8 label[32];
391 __u32 first_reg; /* time overflow in y2106 */
392 __u32 last_reg;
393 __u32 invalidated;
394
395 __u32 flags;
396 /* Size of flash only volumes */
397 __u64 sectors;
398 };
399
400 __u8 pad[128];
401 };
402};
403
404BITMASK(UUID_FLASH_ONLY, struct uuid_entry, flags, 0, 1);
405
406/* Btree nodes */
407
408/* Version 1: Seed pointer into btree node checksum
409 */
410#define BCACHE_BSET_CSUM 1
411#define BCACHE_BSET_VERSION 1
412
413/*
414 * Btree nodes
415 *
416 * On disk a btree node is a list/log of these; within each set the keys are
417 * sorted
418 */
419struct bset {
420 __u64 csum;
421 __u64 magic;
422 __u64 seq;
423 __u32 version;
424 __u32 keys;
425
426 union {
427 struct bkey start[0];
428 __u64 d[0];
429 };
430};
431
432/* OBSOLETE */
433
434/* UUIDS - per backing device/flash only volume metadata */
435
436struct uuid_entry_v0 {
437 __u8 uuid[16];
438 __u8 label[32];
439 __u32 first_reg;
440 __u32 last_reg;
441 __u32 invalidated;
442 __u32 pad;
443};
444
445#endif /* _LINUX_BCACHE_H */