4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License version 2 for more details. A copy is
14 * included in the COPYING file that accompanied this code.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 * Copyright (c) 2014, 2016, Intel Corporation.
26 * lustre/include/lustre_lmv.h
28 * Lustre LMV structures and functions.
30 * Author: Di Wang <di.wang@intel.com>
35 #include <uapi/linux/lustre/lustre_idl.h>
38 struct lu_fid lmo_fid;
40 struct inode *lmo_root;
43 struct lmv_stripe_md {
45 __u32 lsm_md_stripe_count;
46 __u32 lsm_md_master_mdt_index;
47 __u32 lsm_md_hash_type;
48 __u8 lsm_md_max_inherit;
49 __u8 lsm_md_max_inherit_rr;
50 __u32 lsm_md_layout_version;
51 __u32 lsm_md_migrate_offset;
52 __u32 lsm_md_migrate_hash;
53 char lsm_md_pool_name[LOV_MAXPOOLNAME + 1];
54 struct lmv_oinfo lsm_md_oinfo[0];
57 static inline bool lmv_dir_striped(const struct lmv_stripe_md *lsm)
59 return lsm && lsm->lsm_md_magic == LMV_MAGIC;
62 static inline bool lmv_dir_foreign(const struct lmv_stripe_md *lsm)
64 return lsm && lsm->lsm_md_magic == LMV_MAGIC_FOREIGN;
67 static inline bool lmv_dir_layout_changing(const struct lmv_stripe_md *lsm)
69 return lmv_dir_striped(lsm) &&
70 lmv_hash_is_layout_changing(lsm->lsm_md_hash_type);
73 static inline bool lmv_dir_bad_hash(const struct lmv_stripe_md *lsm)
75 if (!lmv_dir_striped(lsm))
78 if (lsm->lsm_md_hash_type & LMV_HASH_FLAG_BAD_TYPE)
81 return !lmv_is_known_hash_type(lsm->lsm_md_hash_type);
85 lsm_md_eq(const struct lmv_stripe_md *lsm1, const struct lmv_stripe_md *lsm2)
89 if (lsm1->lsm_md_magic != lsm2->lsm_md_magic ||
90 lsm1->lsm_md_stripe_count != lsm2->lsm_md_stripe_count ||
91 lsm1->lsm_md_master_mdt_index !=
92 lsm2->lsm_md_master_mdt_index ||
93 lsm1->lsm_md_hash_type != lsm2->lsm_md_hash_type ||
94 lsm1->lsm_md_max_inherit != lsm2->lsm_md_max_inherit ||
95 lsm1->lsm_md_max_inherit_rr != lsm2->lsm_md_max_inherit_rr ||
96 lsm1->lsm_md_layout_version !=
97 lsm2->lsm_md_layout_version ||
98 lsm1->lsm_md_migrate_offset !=
99 lsm2->lsm_md_migrate_offset ||
100 lsm1->lsm_md_migrate_hash !=
101 lsm2->lsm_md_migrate_hash ||
102 strncmp(lsm1->lsm_md_pool_name, lsm2->lsm_md_pool_name,
103 sizeof(lsm1->lsm_md_pool_name)) != 0)
106 if (lmv_dir_striped(lsm1)) {
107 for (idx = 0; idx < lsm1->lsm_md_stripe_count; idx++) {
108 if (!lu_fid_eq(&lsm1->lsm_md_oinfo[idx].lmo_fid,
109 &lsm2->lsm_md_oinfo[idx].lmo_fid))
112 } else if (lsm1->lsm_md_magic == LMV_USER_MAGIC_SPECIFIC) {
113 for (idx = 0; idx < lsm1->lsm_md_stripe_count; idx++) {
114 if (lsm1->lsm_md_oinfo[idx].lmo_mds !=
115 lsm2->lsm_md_oinfo[idx].lmo_mds)
123 static inline void lsm_md_dump(int mask, const struct lmv_stripe_md *lsm)
128 "dump LMV: magic=%#x count=%u index=%u hash=%s:%#x max_inherit=%hhu max_inherit_rr=%hhu version=%u migrate_offset=%u migrate_hash=%s:%x pool=%.*s\n",
129 lsm->lsm_md_magic, lsm->lsm_md_stripe_count,
130 lsm->lsm_md_master_mdt_index,
131 lmv_is_known_hash_type(lsm->lsm_md_hash_type) ?
132 mdt_hash_name[lsm->lsm_md_hash_type & LMV_HASH_TYPE_MASK] :
133 "invalid", lsm->lsm_md_hash_type,
134 lsm->lsm_md_max_inherit, lsm->lsm_md_max_inherit_rr,
135 lsm->lsm_md_layout_version, lsm->lsm_md_migrate_offset,
136 lmv_is_known_hash_type(lsm->lsm_md_migrate_hash) ?
137 mdt_hash_name[lsm->lsm_md_migrate_hash & LMV_HASH_TYPE_MASK] :
138 "invalid", lsm->lsm_md_migrate_hash,
139 LOV_MAXPOOLNAME, lsm->lsm_md_pool_name);
141 if (!lmv_dir_striped(lsm))
144 for (i = 0; i < lsm->lsm_md_stripe_count; i++)
145 CDEBUG(mask, "stripe[%d] "DFID"\n",
146 i, PFID(&lsm->lsm_md_oinfo[i].lmo_fid));
151 void lmv_free_memmd(struct lmv_stripe_md *lsm);
153 static inline void lmv1_le_to_cpu(struct lmv_mds_md_v1 *lmv_dst,
154 const struct lmv_mds_md_v1 *lmv_src)
158 lmv_dst->lmv_magic = le32_to_cpu(lmv_src->lmv_magic);
159 lmv_dst->lmv_stripe_count = le32_to_cpu(lmv_src->lmv_stripe_count);
160 lmv_dst->lmv_master_mdt_index =
161 le32_to_cpu(lmv_src->lmv_master_mdt_index);
162 lmv_dst->lmv_hash_type = le32_to_cpu(lmv_src->lmv_hash_type);
163 lmv_dst->lmv_layout_version = le32_to_cpu(lmv_src->lmv_layout_version);
164 if (lmv_src->lmv_stripe_count > LMV_MAX_STRIPE_COUNT)
166 for (i = 0; i < lmv_src->lmv_stripe_count; i++)
167 fid_le_to_cpu(&lmv_dst->lmv_stripe_fids[i],
168 &lmv_src->lmv_stripe_fids[i]);
171 static inline void lmv_le_to_cpu(union lmv_mds_md *lmv_dst,
172 const union lmv_mds_md *lmv_src)
174 switch (le32_to_cpu(lmv_src->lmv_magic)) {
176 lmv1_le_to_cpu(&lmv_dst->lmv_md_v1, &lmv_src->lmv_md_v1);
183 /* This hash is only for testing purpose */
184 static inline unsigned int
185 lmv_hash_all_chars(unsigned int count, const char *name, int namelen)
188 const unsigned char *p = (const unsigned char *)name;
190 while (--namelen >= 0)
198 static inline unsigned int
199 lmv_hash_fnv1a(unsigned int count, const char *name, int namelen)
203 hash = lustre_hash_fnv_1a_64(name, namelen);
205 return do_div(hash, count);
209 * Robert Jenkins' function for mixing 32-bit values
210 * http://burtleburtle.net/bob/hash/evahash.html
211 * a, b = random bits, c = input and output
213 * Mixing inputs to generate an evenly distributed hash.
215 #define crush_hashmix(a, b, c) \
217 a = a - b; a = a - c; a = a ^ (c >> 13); \
218 b = b - c; b = b - a; b = b ^ (a << 8); \
219 c = c - a; c = c - b; c = c ^ (b >> 13); \
220 a = a - b; a = a - c; a = a ^ (c >> 12); \
221 b = b - c; b = b - a; b = b ^ (a << 16); \
222 c = c - a; c = c - b; c = c ^ (b >> 5); \
223 a = a - b; a = a - c; a = a ^ (c >> 3); \
224 b = b - c; b = b - a; b = b ^ (a << 10); \
225 c = c - a; c = c - b; c = c ^ (b >> 15); \
228 #define crush_hash_seed 1315423911
230 static inline __u32 crush_hash(__u32 a, __u32 b)
232 __u32 hash = crush_hash_seed ^ a ^ b;
236 crush_hashmix(a, b, hash);
237 crush_hashmix(x, a, hash);
238 crush_hashmix(b, y, hash);
243 /* refer to https://github.com/ceph/ceph/blob/master/src/crush/hash.c and
244 * https://www.ssrc.ucsc.edu/Papers/weil-sc06.pdf for details of CRUSH
247 static inline unsigned int
248 lmv_hash_crush(unsigned int count, const char *name, int namelen, bool crush2)
250 unsigned long long straw;
251 unsigned long long highest_straw = 0;
253 unsigned int idx = 0;
256 /* put temp and backup file on the same MDT where target is located.
257 * temporary file naming rule:
258 * 1. rsync: .<target>.XXXXXX
259 * 2. dstripe: <target>.XXXXXXXX
261 if (lu_name_is_temp_file(name, namelen, true, 6, crush2)) {
264 } else if (lu_name_is_temp_file(name, namelen, false, 8, crush2)) {
266 } else if (lu_name_is_backup_file(name, namelen, &i)) {
267 LASSERT(i < namelen);
271 pg_id = lmv_hash_fnv1a(LMV_CRUSH_PG_COUNT, name, namelen);
273 /* distribute PG among all stripes pseudo-randomly, so they are almost
274 * evenly distributed, and when stripe count changes, only (delta /
275 * total) sub files need to be moved, herein 'delta' is added or removed
276 * stripe count, 'total' is total stripe count before change for
277 * removal, or count after change for addition.
279 for (i = 0; i < count; i++) {
280 straw = crush_hash(pg_id, i);
281 if (straw > highest_straw) {
282 highest_straw = straw;
286 LASSERT(idx < count);
291 /* directory layout may change in three ways:
292 * 1. directory migration, in its LMV source stripes are appended after
293 * target stripes, \a migrate_hash is source hash type, \a migrate_offset is
294 * target stripe count,
295 * 2. directory split, \a migrate_hash is hash type before split,
296 * \a migrate_offset is stripe count before split.
297 * 3. directory merge, \a migrate_hash is hash type after merge,
298 * \a migrate_offset is stripe count after merge.
301 __lmv_name_to_stripe_index(__u32 hash_type, __u32 stripe_count,
302 __u32 migrate_hash, __u32 migrate_offset,
303 const char *name, int namelen, bool new_layout)
305 __u32 saved_hash = hash_type;
306 __u32 saved_count = stripe_count;
307 int stripe_index = 0;
309 LASSERT(namelen > 0);
310 LASSERT(stripe_count > 0);
312 if (lmv_hash_is_splitting(hash_type)) {
314 hash_type = migrate_hash;
315 stripe_count = migrate_offset;
317 } else if (lmv_hash_is_merging(hash_type)) {
319 hash_type = migrate_hash;
320 stripe_count = migrate_offset;
322 } else if (lmv_hash_is_migrating(hash_type)) {
324 stripe_count = migrate_offset;
326 hash_type = migrate_hash;
327 stripe_count -= migrate_offset;
331 if (stripe_count > 1) {
332 switch (hash_type & LMV_HASH_TYPE_MASK) {
333 case LMV_HASH_TYPE_ALL_CHARS:
334 stripe_index = lmv_hash_all_chars(stripe_count, name,
337 case LMV_HASH_TYPE_FNV_1A_64:
338 stripe_index = lmv_hash_fnv1a(stripe_count, name,
341 case LMV_HASH_TYPE_CRUSH:
342 stripe_index = lmv_hash_crush(stripe_count, name,
345 case LMV_HASH_TYPE_CRUSH2:
346 stripe_index = lmv_hash_crush(stripe_count, name,
354 LASSERT(stripe_index < stripe_count);
356 if (!new_layout && lmv_hash_is_migrating(saved_hash))
357 stripe_index += migrate_offset;
359 LASSERT(stripe_index < saved_count);
361 CDEBUG(D_INFO, "name %.*s hash=%#x/%#x idx=%d/%u/%u under %s layout\n",
362 namelen, name, saved_hash, migrate_hash, stripe_index,
363 saved_count, migrate_offset, new_layout ? "new" : "old");
368 static inline int lmv_name_to_stripe_index(struct lmv_mds_md_v1 *lmv,
369 const char *name, int namelen)
371 if (lmv->lmv_magic == LMV_MAGIC_V1 ||
372 lmv->lmv_magic == LMV_MAGIC_STRIPE)
373 return __lmv_name_to_stripe_index(lmv->lmv_hash_type,
374 lmv->lmv_stripe_count,
375 lmv->lmv_migrate_hash,
376 lmv->lmv_migrate_offset,
377 name, namelen, true);
379 if (lmv->lmv_magic == cpu_to_le32(LMV_MAGIC_V1) ||
380 lmv->lmv_magic == cpu_to_le32(LMV_MAGIC_STRIPE))
381 return __lmv_name_to_stripe_index(
382 le32_to_cpu(lmv->lmv_hash_type),
383 le32_to_cpu(lmv->lmv_stripe_count),
384 le32_to_cpu(lmv->lmv_migrate_hash),
385 le32_to_cpu(lmv->lmv_migrate_offset),
386 name, namelen, true);
391 static inline int lmv_name_to_stripe_index_old(struct lmv_mds_md_v1 *lmv,
392 const char *name, int namelen)
394 if (lmv->lmv_magic == LMV_MAGIC_V1 ||
395 lmv->lmv_magic == LMV_MAGIC_STRIPE)
396 return __lmv_name_to_stripe_index(lmv->lmv_hash_type,
397 lmv->lmv_stripe_count,
398 lmv->lmv_migrate_hash,
399 lmv->lmv_migrate_offset,
400 name, namelen, false);
402 if (lmv->lmv_magic == cpu_to_le32(LMV_MAGIC_V1) ||
403 lmv->lmv_magic == cpu_to_le32(LMV_MAGIC_STRIPE))
404 return __lmv_name_to_stripe_index(
405 le32_to_cpu(lmv->lmv_hash_type),
406 le32_to_cpu(lmv->lmv_stripe_count),
407 le32_to_cpu(lmv->lmv_migrate_hash),
408 le32_to_cpu(lmv->lmv_migrate_offset),
409 name, namelen, false);
414 static inline bool lmv_user_magic_supported(__u32 lum_magic)
416 return lum_magic == LMV_USER_MAGIC ||
417 lum_magic == LMV_USER_MAGIC_SPECIFIC ||
418 lum_magic == LMV_MAGIC_FOREIGN;
421 #define LMV_DEBUG(mask, lmv, msg) \
423 "%s LMV: magic=%#x count=%u index=%u hash=%s:%#x version=%u migrate_offset=%u migrate_hash=%s:%x pool=%.*s\n",\
424 msg, (lmv)->lmv_magic, (lmv)->lmv_stripe_count, \
425 (lmv)->lmv_master_mdt_index, \
426 lmv_is_known_hash_type((lmv)->lmv_hash_type) ? \
427 mdt_hash_name[(lmv)->lmv_hash_type & LMV_HASH_TYPE_MASK] : \
428 "invalid", (lmv)->lmv_hash_type, \
429 (lmv)->lmv_layout_version, (lmv)->lmv_migrate_offset, \
430 lmv_is_known_hash_type((lmv)->lmv_migrate_hash) ? \
431 mdt_hash_name[(lmv)->lmv_migrate_hash & LMV_HASH_TYPE_MASK] : \
432 "invalid", (lmv)->lmv_migrate_hash, \
433 LOV_MAXPOOLNAME, lmv->lmv_pool_name)
435 /* master LMV is sane */
436 static inline bool lmv_is_sane(const struct lmv_mds_md_v1 *lmv)
441 if (le32_to_cpu(lmv->lmv_magic) != LMV_MAGIC_V1)
444 if (le32_to_cpu(lmv->lmv_stripe_count) == 0)
447 if (!lmv_is_known_hash_type(le32_to_cpu(lmv->lmv_hash_type)))
452 LMV_DEBUG(D_ERROR, lmv, "unknown layout");
456 /* LMV can be either master or stripe LMV */
457 static inline bool lmv_is_sane2(const struct lmv_mds_md_v1 *lmv)
462 if (le32_to_cpu(lmv->lmv_magic) != LMV_MAGIC_V1 &&
463 le32_to_cpu(lmv->lmv_magic) != LMV_MAGIC_STRIPE)
466 if (le32_to_cpu(lmv->lmv_stripe_count) == 0)
469 if (!lmv_is_known_hash_type(le32_to_cpu(lmv->lmv_hash_type)))
474 LMV_DEBUG(D_ERROR, lmv, "unknown layout");
478 static inline bool lmv_is_splitting(const struct lmv_mds_md_v1 *lmv)
480 if (!lmv_is_sane2(lmv))
483 return lmv_hash_is_splitting(cpu_to_le32(lmv->lmv_hash_type));
486 static inline bool lmv_is_merging(const struct lmv_mds_md_v1 *lmv)
488 if (!lmv_is_sane2(lmv))
491 return lmv_hash_is_merging(cpu_to_le32(lmv->lmv_hash_type));
494 static inline bool lmv_is_migrating(const struct lmv_mds_md_v1 *lmv)
496 if (!lmv_is_sane(lmv))
499 return lmv_hash_is_migrating(cpu_to_le32(lmv->lmv_hash_type));
502 static inline bool lmv_is_restriping(const struct lmv_mds_md_v1 *lmv)
504 if (!lmv_is_sane2(lmv))
507 return lmv_hash_is_splitting(cpu_to_le32(lmv->lmv_hash_type)) ||
508 lmv_hash_is_merging(cpu_to_le32(lmv->lmv_hash_type));
511 static inline bool lmv_is_layout_changing(const struct lmv_mds_md_v1 *lmv)
513 if (!lmv_is_sane2(lmv))
516 return lmv_hash_is_splitting(cpu_to_le32(lmv->lmv_hash_type)) ||
517 lmv_hash_is_merging(cpu_to_le32(lmv->lmv_hash_type)) ||
518 lmv_hash_is_migrating(cpu_to_le32(lmv->lmv_hash_type));
521 static inline bool lmv_is_fixed(const struct lmv_mds_md_v1 *lmv)
523 return cpu_to_le32(lmv->lmv_hash_type) & LMV_HASH_FLAG_FIXED;
526 static inline __u8 lmv_inherit_next(__u8 inherit)
528 if (inherit == LMV_INHERIT_END || inherit == LMV_INHERIT_NONE)
529 return LMV_INHERIT_NONE;
531 if (inherit == LMV_INHERIT_UNLIMITED || inherit > LMV_INHERIT_MAX)
537 static inline __u8 lmv_inherit_rr_next(__u8 inherit_rr)
539 if (inherit_rr == LMV_INHERIT_RR_NONE ||
540 inherit_rr == LMV_INHERIT_RR_UNLIMITED ||
541 inherit_rr > LMV_INHERIT_RR_MAX)
544 return inherit_rr - 1;