include/sys/ddt.h

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or https://opensource.org/licenses/CDDL-1.0.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
  23  * Copyright (c) 2016 by Delphix. All rights reserved.
  24  * Copyright (c) 2023, Klara Inc.
  25  */
  26
  27 #ifndef _SYS_DDT_H
  28 #define _SYS_DDT_H
  29
  30 #include <sys/sysmacros.h>
  31 #include <sys/types.h>
  32 #include <sys/fs/zfs.h>
  33 #include <sys/zio.h>
  34 #include <sys/dmu.h>
  35
  36 #ifdef  __cplusplus
  37 extern "C" {
  38 #endif
  39
  40 struct abd;
  41
  42 /*
  43  * DDT-wide feature flags. These are set in ddt_flags by ddt_configure().
  44  */
  45 #define DDT_FLAG_FLAT   (1 << 0)        /* single extensible phys */
  46 #define DDT_FLAG_LOG    (1 << 1)        /* dedup log (journal) */
  47 #define DDT_FLAG_MASK   (DDT_FLAG_FLAT|DDT_FLAG_LOG)
  48
  49 /*
  50  * DDT on-disk storage object types. Each one corresponds to specific
  51  * implementation, see ddt_ops_t. The value itself is not stored on disk.
  52  *
  53  * When searching for an entry, objects types will be searched in this order.
  54  *
  55  * Note that DDT_TYPES is used as the "no type" for new entries that have not
  56  * yet been written to a storage object.
  57  */
  58 typedef enum {
  59         DDT_TYPE_ZAP = 0,       /* ZAP storage object, ddt_zap */
  60         DDT_TYPES
  61 } ddt_type_t;
  62
  63 _Static_assert(DDT_TYPES <= UINT8_MAX,
  64         "ddt_type_t must fit in a uint8_t");
  65
  66 /* New and updated entries recieve this type, see ddt_sync_entry() */
  67 #define DDT_TYPE_DEFAULT        (DDT_TYPE_ZAP)
  68
  69 /*
  70  * DDT storage classes. Each class has a separate storage object for each type.
  71  * The value itself is not stored on disk.
  72  *
  73  * When search for an entry, object classes will be searched in this order.
  74  *
  75  * Note that DDT_CLASSES is used as the "no class" for new entries that have not
  76  * yet been written to a storage object.
  77  */
  78 typedef enum {
  79         DDT_CLASS_DITTO = 0,    /* entry has ditto blocks (obsolete) */
  80         DDT_CLASS_DUPLICATE,    /* entry has multiple references */
  81         DDT_CLASS_UNIQUE,       /* entry has a single reference */
  82         DDT_CLASSES
  83 } ddt_class_t;
  84
  85 _Static_assert(DDT_CLASSES < UINT8_MAX,
  86         "ddt_class_t must fit in a uint8_t");
  87
  88 /*
  89  * The "key" part of an on-disk entry. This is the unique "name" for a block,
  90  * that is, that parts of the block pointer that will always be the same for
  91  * the same data.
  92  */
  93 typedef struct {
  94         zio_cksum_t     ddk_cksum;      /* 256-bit block checksum */
  95         /*
  96          * Encoded with logical & physical size, encryption, and compression,
  97          * as follows:
  98          *   +-------+-------+-------+-------+-------+-------+-------+-------+
  99          *   |   0   |   0   |   0   |X| comp|     PSIZE     |     LSIZE     |
 100          *   +-------+-------+-------+-------+-------+-------+-------+-------+
 101          */
 102         uint64_t        ddk_prop;
 103 } ddt_key_t;
 104
 105 /*
 106  * Macros for accessing parts of a ddt_key_t. These are similar to their BP_*
 107  * counterparts.
 108  */
 109 #define DDK_GET_LSIZE(ddk)      \
 110         BF64_GET_SB((ddk)->ddk_prop, 0, 16, SPA_MINBLOCKSHIFT, 1)
 111 #define DDK_SET_LSIZE(ddk, x)   \
 112         BF64_SET_SB((ddk)->ddk_prop, 0, 16, SPA_MINBLOCKSHIFT, 1, x)
 113
 114 #define DDK_GET_PSIZE(ddk)      \
 115         BF64_GET_SB((ddk)->ddk_prop, 16, 16, SPA_MINBLOCKSHIFT, 1)
 116 #define DDK_SET_PSIZE(ddk, x)   \
 117         BF64_SET_SB((ddk)->ddk_prop, 16, 16, SPA_MINBLOCKSHIFT, 1, x)
 118
 119 #define DDK_GET_COMPRESS(ddk)           BF64_GET((ddk)->ddk_prop, 32, 7)
 120 #define DDK_SET_COMPRESS(ddk, x)        BF64_SET((ddk)->ddk_prop, 32, 7, x)
 121
 122 #define DDK_GET_CRYPT(ddk)              BF64_GET((ddk)->ddk_prop, 39, 1)
 123 #define DDK_SET_CRYPT(ddk, x)   BF64_SET((ddk)->ddk_prop, 39, 1, x)
 124
 125 /*
 126  * The "value" part for an on-disk entry. These are the "physical"
 127  * characteristics of the stored block, such as its location on disk (DVAs),
 128  * birth txg and ref count.
 129  *
 130  * The "traditional" entry has an array of four, one for each number of DVAs
 131  * (copies= property) and another for additional "ditto" copies. Users of the
 132  * traditional struct will specify the variant (index) of the one they want.
 133  *
 134  * The newer "flat" entry has only a single form that is specified using the
 135  * DDT_PHYS_FLAT variant.
 136  *
 137  * Since the value size varies, use one of the size macros when interfacing
 138  * with the ddt zap.
 139  */
 140
 141 #define DDT_PHYS_MAX    (4)
 142
 143 /*
 144  * Note - this can be used in a flexible array and allocated for
 145  * a specific size (ddp_trad or ddp_flat). So be careful not to
 146  * copy using "=" assignment but instead use ddt_phys_copy().
 147  */
 148 typedef union {
 149         /*
 150          * Traditional physical payload value for DDT zap (256 bytes)
 151          */
 152         struct {
 153                 dva_t           ddp_dva[SPA_DVAS_PER_BP];
 154                 uint64_t        ddp_refcnt;
 155                 uint64_t        ddp_phys_birth;
 156         } ddp_trad[DDT_PHYS_MAX];
 157
 158         /*
 159          * Flat physical payload value for DDT zap (72 bytes)
 160          */
 161         struct {
 162                 dva_t           ddp_dva[SPA_DVAS_PER_BP];
 163                 uint64_t        ddp_refcnt;
 164                 uint64_t        ddp_phys_birth; /* txg based from BP */
 165                 uint64_t        ddp_class_start; /* in realtime seconds */
 166         } ddp_flat;
 167 } ddt_univ_phys_t;
 168
 169 /*
 170  * This enum denotes which variant of a ddt_univ_phys_t to target. For
 171  * a traditional DDT entry, it represents the indexes into the ddp_trad
 172  * array. Any consumer of a ddt_univ_phys_t needs to know which variant
 173  * is being targeted.
 174  *
 175  * Note, we no longer generate new DDT_PHYS_DITTO-type blocks.  However,
 176  * we maintain the ability to free existing dedup-ditto blocks.
 177  */
 178
 179 typedef enum {
 180         DDT_PHYS_DITTO = 0,
 181         DDT_PHYS_SINGLE = 1,
 182         DDT_PHYS_DOUBLE = 2,
 183         DDT_PHYS_TRIPLE = 3,
 184         DDT_PHYS_FLAT = 4,
 185         DDT_PHYS_NONE = 5
 186 } ddt_phys_variant_t;
 187
 188 #define DDT_PHYS_VARIANT(ddt, p)        \
 189         (ASSERT((p) < DDT_PHYS_NONE),   \
 190         ((ddt)->ddt_flags & DDT_FLAG_FLAT ? DDT_PHYS_FLAT : (p)))
 191
 192 #define DDT_TRAD_PHYS_SIZE      sizeof (((ddt_univ_phys_t *)0)->ddp_trad)
 193 #define DDT_FLAT_PHYS_SIZE      sizeof (((ddt_univ_phys_t *)0)->ddp_flat)
 194
 195 #define _DDT_PHYS_SWITCH(ddt, flat, trad)       \
 196         (((ddt)->ddt_flags & DDT_FLAG_FLAT) ? (flat) : (trad))
 197
 198 #define DDT_PHYS_SIZE(ddt)              _DDT_PHYS_SWITCH(ddt,   \
 199         DDT_FLAT_PHYS_SIZE, DDT_TRAD_PHYS_SIZE)
 200
 201 #define DDT_NPHYS(ddt)                  _DDT_PHYS_SWITCH(ddt, 1, DDT_PHYS_MAX)
 202 #define DDT_PHYS_FOR_COPIES(ddt, p)     _DDT_PHYS_SWITCH(ddt, 0, p)
 203 #define DDT_PHYS_IS_DITTO(ddt, p)       _DDT_PHYS_SWITCH(ddt, 0, (p == 0))
 204
 205 /*
 206  * A "live" entry, holding changes to an entry made this txg, and other data to
 207  * support loading, updating and repairing the entry.
 208  */
 209
 210 /* State flags for dde_flags */
 211 #define DDE_FLAG_LOADED         (1 << 0)        /* entry ready for use */
 212 #define DDE_FLAG_OVERQUOTA      (1 << 1)        /* entry unusable, no space */
 213 #define DDE_FLAG_LOGGED         (1 << 2)        /* loaded from log */
 214
 215 /*
 216  * Additional data to support entry update or repair. This is fixed size
 217  * because its relatively rarely used.
 218  */
 219 typedef struct {
 220         /* copy of data after a repair read, to be rewritten */
 221         abd_t           *dde_repair_abd;
 222
 223         /* original phys contents before update, for error handling */
 224         ddt_univ_phys_t dde_orig_phys;
 225
 226         /* in-flight update IOs */
 227         zio_t           *dde_lead_zio[DDT_PHYS_MAX];
 228 } ddt_entry_io_t;
 229
 230 typedef struct {
 231         /* key must be first for ddt_key_compare */
 232         ddt_key_t       dde_key;        /* ddt_tree key */
 233         avl_node_t      dde_node;       /* ddt_tree_node */
 234
 235         /* storage type and class the entry was loaded from */
 236         ddt_type_t      dde_type;
 237         ddt_class_t     dde_class;
 238
 239         uint8_t         dde_flags;      /* load state flags */
 240         kcondvar_t      dde_cv;         /* signaled when load completes */
 241         uint64_t        dde_waiters;    /* count of waiters on dde_cv */
 242
 243         ddt_entry_io_t  *dde_io;        /* IO support, when required */
 244
 245         ddt_univ_phys_t dde_phys[];     /* flexible -- allocated size varies */
 246 } ddt_entry_t;
 247
 248 /*
 249  * A lightweight entry is for short-lived or transient uses, like iterating or
 250  * inspecting, when you don't care where it came from.
 251  */
 252 typedef struct {
 253         ddt_key_t       ddlwe_key;
 254         ddt_type_t      ddlwe_type;
 255         ddt_class_t     ddlwe_class;
 256         ddt_univ_phys_t ddlwe_phys;
 257 } ddt_lightweight_entry_t;
 258
 259 /*
 260  * In-core DDT log. A separate struct to make it easier to switch between the
 261  * appending and flushing logs.
 262  */
 263 typedef struct {
 264         avl_tree_t      ddl_tree;       /* logged entries */
 265         uint32_t        ddl_flags;      /* flags for this log */
 266         uint64_t        ddl_object;     /* log object id */
 267         uint64_t        ddl_length;     /* on-disk log size */
 268         uint64_t        ddl_first_txg;  /* txg log became active */
 269         ddt_key_t       ddl_checkpoint; /* last checkpoint */
 270 } ddt_log_t;
 271
 272 /*
 273  * In-core DDT object. This covers all entries and stats for a the whole pool
 274  * for a given checksum type.
 275  */
 276 typedef struct {
 277         kmutex_t        ddt_lock;       /* protects changes to all fields */
 278
 279         avl_tree_t      ddt_tree;       /* "live" (changed) entries this txg */
 280         avl_tree_t      ddt_log_tree;   /* logged entries */
 281
 282         avl_tree_t      ddt_repair_tree;        /* entries being repaired */
 283
 284         ddt_log_t       ddt_log[2];             /* active/flushing logs */
 285         ddt_log_t       *ddt_log_active;        /* pointers into ddt_log */
 286         ddt_log_t       *ddt_log_flushing;      /* swapped when flush starts */
 287
 288         hrtime_t        ddt_flush_start;        /* log flush start this txg */
 289         uint32_t        ddt_flush_pass;         /* log flush pass this txg */
 290
 291         int32_t         ddt_flush_count;        /* entries flushed this txg */
 292         int32_t         ddt_flush_min;          /* min rem entries to flush */
 293         int32_t         ddt_log_ingest_rate;    /* rolling log ingest rate */
 294         int32_t         ddt_log_flush_rate;     /* rolling log flush rate */
 295         int32_t         ddt_log_flush_time_rate; /* avg time spent flushing */
 296
 297         uint64_t        ddt_flush_force_txg;    /* flush hard before this txg */
 298
 299         kstat_t         *ddt_ksp;       /* kstats context */
 300
 301         enum zio_checksum ddt_checksum; /* checksum algorithm in use */
 302         spa_t           *ddt_spa;       /* pool this ddt is on */
 303         objset_t        *ddt_os;        /* ddt objset (always MOS) */
 304
 305         uint64_t        ddt_dir_object; /* MOS dir holding ddt objects */
 306         uint64_t        ddt_version;    /* DDT version */
 307         uint64_t        ddt_flags;      /* FDT option flags */
 308
 309         /* per-type/per-class entry store objects */
 310         uint64_t        ddt_object[DDT_TYPES][DDT_CLASSES];
 311
 312         /* object ids for stored, logged and per-type/per-class stats */
 313         uint64_t        ddt_stat_object;
 314         ddt_object_t    ddt_log_stats;
 315         ddt_object_t    ddt_object_stats[DDT_TYPES][DDT_CLASSES];
 316
 317         /* type/class stats by power-2-sized referenced blocks */
 318         ddt_histogram_t ddt_histogram[DDT_TYPES][DDT_CLASSES];
 319         ddt_histogram_t ddt_histogram_cache[DDT_TYPES][DDT_CLASSES];
 320
 321         /* log stats power-2-sized referenced blocks */
 322         ddt_histogram_t ddt_log_histogram;
 323 } ddt_t;
 324
 325 /*
 326  * In-core and on-disk bookmark for DDT walks. This is a cursor for ddt_walk(),
 327  * and is stable across calls, even if the DDT is updated, the pool is
 328  * restarted or loaded on another system, or OpenZFS is upgraded.
 329  */
 330 typedef struct {
 331         uint64_t        ddb_class;
 332         uint64_t        ddb_type;
 333         uint64_t        ddb_checksum;
 334         uint64_t        ddb_cursor;
 335 } ddt_bookmark_t;
 336
 337 extern void ddt_bp_fill(const ddt_univ_phys_t *ddp, ddt_phys_variant_t v,
 338     blkptr_t *bp, uint64_t txg);
 339 extern void ddt_bp_create(enum zio_checksum checksum, const ddt_key_t *ddk,
 340     const ddt_univ_phys_t *ddp, ddt_phys_variant_t v, blkptr_t *bp);
 341
 342 extern void ddt_phys_extend(ddt_univ_phys_t *ddp, ddt_phys_variant_t v,
 343     const blkptr_t *bp);
 344 extern void ddt_phys_copy(ddt_univ_phys_t *dst, const ddt_univ_phys_t *src,
 345     ddt_phys_variant_t v);
 346 extern void ddt_phys_clear(ddt_univ_phys_t *ddp, ddt_phys_variant_t v);
 347 extern void ddt_phys_addref(ddt_univ_phys_t *ddp, ddt_phys_variant_t v);
 348 extern uint64_t ddt_phys_decref(ddt_univ_phys_t *ddp, ddt_phys_variant_t v);
 349 extern uint64_t ddt_phys_refcnt(const ddt_univ_phys_t *ddp,
 350     ddt_phys_variant_t v);
 351 extern ddt_phys_variant_t ddt_phys_select(const ddt_t *ddt,
 352     const ddt_entry_t *dde, const blkptr_t *bp);
 353 extern uint64_t ddt_phys_birth(const ddt_univ_phys_t *ddp,
 354     ddt_phys_variant_t v);
 355 extern int ddt_phys_dva_count(const ddt_univ_phys_t *ddp, ddt_phys_variant_t v,
 356     boolean_t encrypted);
 357
 358 extern void ddt_histogram_add_entry(ddt_t *ddt, ddt_histogram_t *ddh,
 359     const ddt_lightweight_entry_t *ddlwe);
 360 extern void ddt_histogram_sub_entry(ddt_t *ddt, ddt_histogram_t *ddh,
 361     const ddt_lightweight_entry_t *ddlwe);
 362
 363 extern void ddt_histogram_add(ddt_histogram_t *dst, const ddt_histogram_t *src);
 364 extern void ddt_histogram_total(ddt_stat_t *dds, const ddt_histogram_t *ddh);
 365 extern boolean_t ddt_histogram_empty(const ddt_histogram_t *ddh);
 366
 367 extern void ddt_get_dedup_object_stats(spa_t *spa, ddt_object_t *ddo);
 368 extern uint64_t ddt_get_ddt_dsize(spa_t *spa);
 369 extern void ddt_get_dedup_histogram(spa_t *spa, ddt_histogram_t *ddh);
 370 extern void ddt_get_dedup_stats(spa_t *spa, ddt_stat_t *dds_total);
 371
 372 extern uint64_t ddt_get_dedup_dspace(spa_t *spa);
 373 extern uint64_t ddt_get_pool_dedup_ratio(spa_t *spa);
 374 extern int ddt_get_pool_dedup_cached(spa_t *spa, uint64_t *psize);
 375
 376 extern ddt_t *ddt_select(spa_t *spa, const blkptr_t *bp);
 377 extern void ddt_enter(ddt_t *ddt);
 378 extern void ddt_exit(ddt_t *ddt);
 379 extern void ddt_init(void);
 380 extern void ddt_fini(void);
 381 extern ddt_entry_t *ddt_lookup(ddt_t *ddt, const blkptr_t *bp);
 382 extern void ddt_remove(ddt_t *ddt, ddt_entry_t *dde);
 383 extern void ddt_prefetch(spa_t *spa, const blkptr_t *bp);
 384 extern void ddt_prefetch_all(spa_t *spa);
 385
 386 extern boolean_t ddt_class_contains(spa_t *spa, ddt_class_t max_class,
 387     const blkptr_t *bp);
 388
 389 extern void ddt_alloc_entry_io(ddt_entry_t *dde);
 390
 391 extern ddt_entry_t *ddt_repair_start(ddt_t *ddt, const blkptr_t *bp);
 392 extern void ddt_repair_done(ddt_t *ddt, ddt_entry_t *dde);
 393
 394 extern int ddt_key_compare(const void *x1, const void *x2);
 395
 396 extern void ddt_create(spa_t *spa);
 397 extern int ddt_load(spa_t *spa);
 398 extern void ddt_unload(spa_t *spa);
 399 extern void ddt_sync(spa_t *spa, uint64_t txg);
 400
 401 extern void ddt_walk_init(spa_t *spa, uint64_t txg);
 402 extern boolean_t ddt_walk_ready(spa_t *spa);
 403 extern int ddt_walk(spa_t *spa, ddt_bookmark_t *ddb,
 404     ddt_lightweight_entry_t *ddlwe);
 405
 406 extern boolean_t ddt_addref(spa_t *spa, const blkptr_t *bp);
 407
 408 extern int ddt_prune_unique_entries(spa_t *spa, zpool_ddt_prune_unit_t unit,
 409     uint64_t amount);
 410
 411 #ifdef  __cplusplus
 412 }
 413 #endif
 414
 415 #endif  /* _SYS_DDT_H */