include/sys/zio.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 http://www.opensolaris.org/os/licensing.
  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 /*
  23  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
  25  * Copyright (c) 2012, 2018 by Delphix. All rights reserved.
  26  * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
  27  * Copyright (c) 2013, Joyent, Inc. All rights reserved.
  28  * Copyright 2016 Toomas Soome <tsoome@me.com>
  29  */
  30
  31 #ifndef _ZIO_H
  32 #define _ZIO_H
  33
  34 #include <sys/zio_priority.h>
  35 #include <sys/zfs_context.h>
  36 #include <sys/spa.h>
  37 #include <sys/txg.h>
  38 #include <sys/avl.h>
  39 #include <sys/fs/zfs.h>
  40 #include <sys/zio_impl.h>
  41
  42 #ifdef  __cplusplus
  43 extern "C" {
  44 #endif
  45
  46 /*
  47  * Embedded checksum
  48  */
  49 #define ZEC_MAGIC       0x210da7ab10c7a11ULL
  50
  51 typedef struct zio_eck {
  52         uint64_t        zec_magic;      /* for validation, endianness   */
  53         zio_cksum_t     zec_cksum;      /* 256-bit checksum             */
  54 } zio_eck_t;
  55
  56 /*
  57  * Gang block headers are self-checksumming and contain an array
  58  * of block pointers.
  59  */
  60 #define SPA_GANGBLOCKSIZE       SPA_MINBLOCKSIZE
  61 #define SPA_GBH_NBLKPTRS        ((SPA_GANGBLOCKSIZE - \
  62         sizeof (zio_eck_t)) / sizeof (blkptr_t))
  63 #define SPA_GBH_FILLER          ((SPA_GANGBLOCKSIZE - \
  64         sizeof (zio_eck_t) - \
  65         (SPA_GBH_NBLKPTRS * sizeof (blkptr_t))) /\
  66         sizeof (uint64_t))
  67
  68 typedef struct zio_gbh {
  69         blkptr_t                zg_blkptr[SPA_GBH_NBLKPTRS];
  70         uint64_t                zg_filler[SPA_GBH_FILLER];
  71         zio_eck_t               zg_tail;
  72 } zio_gbh_phys_t;
  73
  74 enum zio_checksum {
  75         ZIO_CHECKSUM_INHERIT = 0,
  76         ZIO_CHECKSUM_ON,
  77         ZIO_CHECKSUM_OFF,
  78         ZIO_CHECKSUM_LABEL,
  79         ZIO_CHECKSUM_GANG_HEADER,
  80         ZIO_CHECKSUM_ZILOG,
  81         ZIO_CHECKSUM_FLETCHER_2,
  82         ZIO_CHECKSUM_FLETCHER_4,
  83         ZIO_CHECKSUM_SHA256,
  84         ZIO_CHECKSUM_ZILOG2,
  85         ZIO_CHECKSUM_NOPARITY,
  86         ZIO_CHECKSUM_SHA512,
  87         ZIO_CHECKSUM_SKEIN,
  88         ZIO_CHECKSUM_EDONR,
  89         ZIO_CHECKSUM_FUNCTIONS
  90 };
  91
  92 /*
  93  * The number of "legacy" compression functions which can be set on individual
  94  * objects.
  95  */
  96 #define ZIO_CHECKSUM_LEGACY_FUNCTIONS ZIO_CHECKSUM_ZILOG2
  97
  98 #define ZIO_CHECKSUM_ON_VALUE   ZIO_CHECKSUM_FLETCHER_4
  99 #define ZIO_CHECKSUM_DEFAULT    ZIO_CHECKSUM_ON
 100
 101 #define ZIO_CHECKSUM_MASK       0xffULL
 102 #define ZIO_CHECKSUM_VERIFY     (1 << 8)
 103
 104 #define ZIO_DEDUPCHECKSUM       ZIO_CHECKSUM_SHA256
 105 #define ZIO_DEDUPDITTO_MIN      100
 106
 107 /* supported encryption algorithms */
 108 enum zio_encrypt {
 109         ZIO_CRYPT_INHERIT = 0,
 110         ZIO_CRYPT_ON,
 111         ZIO_CRYPT_OFF,
 112         ZIO_CRYPT_AES_128_CCM,
 113         ZIO_CRYPT_AES_192_CCM,
 114         ZIO_CRYPT_AES_256_CCM,
 115         ZIO_CRYPT_AES_128_GCM,
 116         ZIO_CRYPT_AES_192_GCM,
 117         ZIO_CRYPT_AES_256_GCM,
 118         ZIO_CRYPT_FUNCTIONS
 119 };
 120
 121 #define ZIO_CRYPT_ON_VALUE      ZIO_CRYPT_AES_256_CCM
 122 #define ZIO_CRYPT_DEFAULT       ZIO_CRYPT_OFF
 123
 124 /* macros defining encryption lengths */
 125 #define ZIO_OBJSET_MAC_LEN              32
 126 #define ZIO_DATA_IV_LEN                 12
 127 #define ZIO_DATA_SALT_LEN               8
 128 #define ZIO_DATA_MAC_LEN                16
 129
 130 /*
 131  * The number of "legacy" compression functions which can be set on individual
 132  * objects.
 133  */
 134 #define ZIO_COMPRESS_LEGACY_FUNCTIONS ZIO_COMPRESS_LZ4
 135
 136 /*
 137  * The meaning of "compress = on" selected by the compression features enabled
 138  * on a given pool.
 139  */
 140 #define ZIO_COMPRESS_LEGACY_ON_VALUE    ZIO_COMPRESS_LZJB
 141 #define ZIO_COMPRESS_LZ4_ON_VALUE       ZIO_COMPRESS_LZ4
 142
 143 #define ZIO_COMPRESS_DEFAULT            ZIO_COMPRESS_OFF
 144
 145 #define BOOTFS_COMPRESS_VALID(compress)                 \
 146         ((compress) == ZIO_COMPRESS_LZJB ||             \
 147         (compress) == ZIO_COMPRESS_LZ4 ||               \
 148         (compress) == ZIO_COMPRESS_GZIP_1 ||            \
 149         (compress) == ZIO_COMPRESS_GZIP_2 ||            \
 150         (compress) == ZIO_COMPRESS_GZIP_3 ||            \
 151         (compress) == ZIO_COMPRESS_GZIP_4 ||            \
 152         (compress) == ZIO_COMPRESS_GZIP_5 ||            \
 153         (compress) == ZIO_COMPRESS_GZIP_6 ||            \
 154         (compress) == ZIO_COMPRESS_GZIP_7 ||            \
 155         (compress) == ZIO_COMPRESS_GZIP_8 ||            \
 156         (compress) == ZIO_COMPRESS_GZIP_9 ||            \
 157         (compress) == ZIO_COMPRESS_ZLE ||               \
 158         (compress) == ZIO_COMPRESS_ON ||                \
 159         (compress) == ZIO_COMPRESS_OFF)
 160
 161 /*
 162  * Default Linux timeout for a sd device.
 163  */
 164 #define ZIO_DELAY_MAX                   (30 * MILLISEC)
 165
 166 #define ZIO_FAILURE_MODE_WAIT           0
 167 #define ZIO_FAILURE_MODE_CONTINUE       1
 168 #define ZIO_FAILURE_MODE_PANIC          2
 169
 170 typedef enum zio_suspend_reason {
 171         ZIO_SUSPEND_NONE = 0,
 172         ZIO_SUSPEND_IOERR,
 173         ZIO_SUSPEND_MMP,
 174 } zio_suspend_reason_t;
 175
 176 enum zio_flag {
 177         /*
 178          * Flags inherited by gang, ddt, and vdev children,
 179          * and that must be equal for two zios to aggregate
 180          */
 181         ZIO_FLAG_DONT_AGGREGATE = 1 << 0,
 182         ZIO_FLAG_IO_REPAIR      = 1 << 1,
 183         ZIO_FLAG_SELF_HEAL      = 1 << 2,
 184         ZIO_FLAG_RESILVER       = 1 << 3,
 185         ZIO_FLAG_SCRUB          = 1 << 4,
 186         ZIO_FLAG_SCAN_THREAD    = 1 << 5,
 187         ZIO_FLAG_PHYSICAL       = 1 << 6,
 188
 189 #define ZIO_FLAG_AGG_INHERIT    (ZIO_FLAG_CANFAIL - 1)
 190
 191         /*
 192          * Flags inherited by ddt, gang, and vdev children.
 193          */
 194         ZIO_FLAG_CANFAIL        = 1 << 7,       /* must be first for INHERIT */
 195         ZIO_FLAG_SPECULATIVE    = 1 << 8,
 196         ZIO_FLAG_CONFIG_WRITER  = 1 << 9,
 197         ZIO_FLAG_DONT_RETRY     = 1 << 10,
 198         ZIO_FLAG_DONT_CACHE     = 1 << 11,
 199         ZIO_FLAG_NODATA         = 1 << 12,
 200         ZIO_FLAG_INDUCE_DAMAGE  = 1 << 13,
 201         ZIO_FLAG_IO_ALLOCATING  = 1 << 14,
 202
 203 #define ZIO_FLAG_DDT_INHERIT    (ZIO_FLAG_IO_RETRY - 1)
 204 #define ZIO_FLAG_GANG_INHERIT   (ZIO_FLAG_IO_RETRY - 1)
 205
 206         /*
 207          * Flags inherited by vdev children.
 208          */
 209         ZIO_FLAG_IO_RETRY       = 1 << 15,      /* must be first for INHERIT */
 210         ZIO_FLAG_PROBE          = 1 << 16,
 211         ZIO_FLAG_TRYHARD        = 1 << 17,
 212         ZIO_FLAG_OPTIONAL       = 1 << 18,
 213
 214 #define ZIO_FLAG_VDEV_INHERIT   (ZIO_FLAG_DONT_QUEUE - 1)
 215
 216         /*
 217          * Flags not inherited by any children.
 218          */
 219         ZIO_FLAG_DONT_QUEUE     = 1 << 19,      /* must be first for INHERIT */
 220         ZIO_FLAG_DONT_PROPAGATE = 1 << 20,
 221         ZIO_FLAG_IO_BYPASS      = 1 << 21,
 222         ZIO_FLAG_IO_REWRITE     = 1 << 22,
 223         ZIO_FLAG_RAW_COMPRESS   = 1 << 23,
 224         ZIO_FLAG_RAW_ENCRYPT    = 1 << 24,
 225         ZIO_FLAG_GANG_CHILD     = 1 << 25,
 226         ZIO_FLAG_DDT_CHILD      = 1 << 26,
 227         ZIO_FLAG_GODFATHER      = 1 << 27,
 228         ZIO_FLAG_NOPWRITE       = 1 << 28,
 229         ZIO_FLAG_REEXECUTED     = 1 << 29,
 230         ZIO_FLAG_DELEGATED      = 1 << 30,
 231         ZIO_FLAG_FASTWRITE      = 1 << 31,
 232 };
 233
 234 #define ZIO_FLAG_MUSTSUCCEED            0
 235 #define ZIO_FLAG_RAW    (ZIO_FLAG_RAW_COMPRESS | ZIO_FLAG_RAW_ENCRYPT)
 236
 237 #define ZIO_DDT_CHILD_FLAGS(zio)                                \
 238         (((zio)->io_flags & ZIO_FLAG_DDT_INHERIT) |             \
 239         ZIO_FLAG_DDT_CHILD | ZIO_FLAG_CANFAIL)
 240
 241 #define ZIO_GANG_CHILD_FLAGS(zio)                               \
 242         (((zio)->io_flags & ZIO_FLAG_GANG_INHERIT) |            \
 243         ZIO_FLAG_GANG_CHILD | ZIO_FLAG_CANFAIL)
 244
 245 #define ZIO_VDEV_CHILD_FLAGS(zio)                               \
 246         (((zio)->io_flags & ZIO_FLAG_VDEV_INHERIT) |            \
 247         ZIO_FLAG_DONT_PROPAGATE | ZIO_FLAG_CANFAIL)
 248
 249 #define ZIO_CHILD_BIT(x)                (1 << (x))
 250 #define ZIO_CHILD_BIT_IS_SET(val, x)    ((val) & (1 << (x)))
 251
 252 enum zio_child {
 253         ZIO_CHILD_VDEV = 0,
 254         ZIO_CHILD_GANG,
 255         ZIO_CHILD_DDT,
 256         ZIO_CHILD_LOGICAL,
 257         ZIO_CHILD_TYPES
 258 };
 259
 260 #define ZIO_CHILD_VDEV_BIT              ZIO_CHILD_BIT(ZIO_CHILD_VDEV)
 261 #define ZIO_CHILD_GANG_BIT              ZIO_CHILD_BIT(ZIO_CHILD_GANG)
 262 #define ZIO_CHILD_DDT_BIT               ZIO_CHILD_BIT(ZIO_CHILD_DDT)
 263 #define ZIO_CHILD_LOGICAL_BIT           ZIO_CHILD_BIT(ZIO_CHILD_LOGICAL)
 264 #define ZIO_CHILD_ALL_BITS                                      \
 265         (ZIO_CHILD_VDEV_BIT | ZIO_CHILD_GANG_BIT |              \
 266         ZIO_CHILD_DDT_BIT | ZIO_CHILD_LOGICAL_BIT)
 267
 268 enum zio_wait_type {
 269         ZIO_WAIT_READY = 0,
 270         ZIO_WAIT_DONE,
 271         ZIO_WAIT_TYPES
 272 };
 273
 274 /*
 275  * We'll take the unused errnos, 'EBADE' and 'EBADR' (from the Convergent
 276  * graveyard) to indicate checksum errors and fragmentation.
 277  */
 278 #define ECKSUM  EBADE
 279 #define EFRAGS  EBADR
 280
 281 /* Similar for ENOACTIVE */
 282 #define ENOTACTIVE      ENOANO
 283
 284 typedef void zio_done_func_t(zio_t *zio);
 285
 286 extern int zio_dva_throttle_enabled;
 287 extern const char *zio_type_name[ZIO_TYPES];
 288
 289 /*
 290  * A bookmark is a four-tuple <objset, object, level, blkid> that uniquely
 291  * identifies any block in the pool.  By convention, the meta-objset (MOS)
 292  * is objset 0, and the meta-dnode is object 0.  This covers all blocks
 293  * except root blocks and ZIL blocks, which are defined as follows:
 294  *
 295  * Root blocks (objset_phys_t) are object 0, level -1:  <objset, 0, -1, 0>.
 296  * ZIL blocks are bookmarked <objset, 0, -2, blkid == ZIL sequence number>.
 297  * dmu_sync()ed ZIL data blocks are bookmarked <objset, object, -2, blkid>.
 298  * dnode visit bookmarks are <objset, object id of dnode, -3, 0>.
 299  *
 300  * Note: this structure is called a bookmark because its original purpose
 301  * was to remember where to resume a pool-wide traverse.
 302  *
 303  * Note: this structure is passed between userland and the kernel, and is
 304  * stored on disk (by virtue of being incorporated into other on-disk
 305  * structures, e.g. dsl_scan_phys_t).
 306  */
 307 struct zbookmark_phys {
 308         uint64_t        zb_objset;
 309         uint64_t        zb_object;
 310         int64_t         zb_level;
 311         uint64_t        zb_blkid;
 312 };
 313
 314 #define SET_BOOKMARK(zb, objset, object, level, blkid)  \
 315 {                                                       \
 316         (zb)->zb_objset = objset;                       \
 317         (zb)->zb_object = object;                       \
 318         (zb)->zb_level = level;                         \
 319         (zb)->zb_blkid = blkid;                         \
 320 }
 321
 322 #define ZB_DESTROYED_OBJSET     (-1ULL)
 323
 324 #define ZB_ROOT_OBJECT          (0ULL)
 325 #define ZB_ROOT_LEVEL           (-1LL)
 326 #define ZB_ROOT_BLKID           (0ULL)
 327
 328 #define ZB_ZIL_OBJECT           (0ULL)
 329 #define ZB_ZIL_LEVEL            (-2LL)
 330
 331 #define ZB_DNODE_LEVEL          (-3LL)
 332 #define ZB_DNODE_BLKID          (0ULL)
 333
 334 #define ZB_IS_ZERO(zb)                                          \
 335         ((zb)->zb_objset == 0 && (zb)->zb_object == 0 &&        \
 336         (zb)->zb_level == 0 && (zb)->zb_blkid == 0)
 337 #define ZB_IS_ROOT(zb)                          \
 338         ((zb)->zb_object == ZB_ROOT_OBJECT &&   \
 339         (zb)->zb_level == ZB_ROOT_LEVEL &&      \
 340         (zb)->zb_blkid == ZB_ROOT_BLKID)
 341
 342 typedef struct zio_prop {
 343         enum zio_checksum       zp_checksum;
 344         enum zio_compress       zp_compress;
 345         dmu_object_type_t       zp_type;
 346         uint8_t                 zp_level;
 347         uint8_t                 zp_copies;
 348         boolean_t               zp_dedup;
 349         boolean_t               zp_dedup_verify;
 350         boolean_t               zp_nopwrite;
 351         boolean_t               zp_encrypt;
 352         boolean_t               zp_byteorder;
 353         uint8_t                 zp_salt[ZIO_DATA_SALT_LEN];
 354         uint8_t                 zp_iv[ZIO_DATA_IV_LEN];
 355         uint8_t                 zp_mac[ZIO_DATA_MAC_LEN];
 356         uint32_t                zp_zpl_smallblk;
 357 } zio_prop_t;
 358
 359 typedef struct zio_cksum_report zio_cksum_report_t;
 360
 361 typedef void zio_cksum_finish_f(zio_cksum_report_t *rep,
 362     const abd_t *good_data);
 363 typedef void zio_cksum_free_f(void *cbdata, size_t size);
 364
 365 struct zio_bad_cksum;                           /* defined in zio_checksum.h */
 366 struct dnode_phys;
 367 struct abd;
 368
 369 struct zio_cksum_report {
 370         struct zio_cksum_report *zcr_next;
 371         nvlist_t                *zcr_ereport;
 372         nvlist_t                *zcr_detector;
 373         void                    *zcr_cbdata;
 374         size_t                  zcr_cbinfo;     /* passed to zcr_free() */
 375         uint64_t                zcr_align;
 376         uint64_t                zcr_length;
 377         zio_cksum_finish_f      *zcr_finish;
 378         zio_cksum_free_f        *zcr_free;
 379
 380         /* internal use only */
 381         struct zio_bad_cksum    *zcr_ckinfo;    /* information from failure */
 382 };
 383
 384 typedef void zio_vsd_cksum_report_f(zio_t *zio, zio_cksum_report_t *zcr,
 385     void *arg);
 386
 387 zio_vsd_cksum_report_f  zio_vsd_default_cksum_report;
 388
 389 typedef struct zio_vsd_ops {
 390         zio_done_func_t         *vsd_free;
 391         zio_vsd_cksum_report_f  *vsd_cksum_report;
 392 } zio_vsd_ops_t;
 393
 394 typedef struct zio_gang_node {
 395         zio_gbh_phys_t          *gn_gbh;
 396         struct zio_gang_node    *gn_child[SPA_GBH_NBLKPTRS];
 397 } zio_gang_node_t;
 398
 399 typedef zio_t *zio_gang_issue_func_t(zio_t *zio, blkptr_t *bp,
 400     zio_gang_node_t *gn, struct abd *data, uint64_t offset);
 401
 402 typedef void zio_transform_func_t(zio_t *zio, struct abd *data, uint64_t size);
 403
 404 typedef struct zio_transform {
 405         struct abd              *zt_orig_abd;
 406         uint64_t                zt_orig_size;
 407         uint64_t                zt_bufsize;
 408         zio_transform_func_t    *zt_transform;
 409         struct zio_transform    *zt_next;
 410 } zio_transform_t;
 411
 412 typedef zio_t *zio_pipe_stage_t(zio_t *zio);
 413
 414 /*
 415  * The io_reexecute flags are distinct from io_flags because the child must
 416  * be able to propagate them to the parent.  The normal io_flags are local
 417  * to the zio, not protected by any lock, and not modifiable by children;
 418  * the reexecute flags are protected by io_lock, modifiable by children,
 419  * and always propagated -- even when ZIO_FLAG_DONT_PROPAGATE is set.
 420  */
 421 #define ZIO_REEXECUTE_NOW       0x01
 422 #define ZIO_REEXECUTE_SUSPEND   0x02
 423
 424 typedef struct zio_alloc_list {
 425         list_t  zal_list;
 426         uint64_t zal_size;
 427 } zio_alloc_list_t;
 428
 429 typedef struct zio_link {
 430         zio_t           *zl_parent;
 431         zio_t           *zl_child;
 432         list_node_t     zl_parent_node;
 433         list_node_t     zl_child_node;
 434 } zio_link_t;
 435
 436 struct zio {
 437         /* Core information about this I/O */
 438         zbookmark_phys_t        io_bookmark;
 439         zio_prop_t      io_prop;
 440         zio_type_t      io_type;
 441         enum zio_child  io_child_type;
 442         int             io_cmd;
 443         zio_priority_t  io_priority;
 444         uint8_t         io_reexecute;
 445         uint8_t         io_state[ZIO_WAIT_TYPES];
 446         uint64_t        io_txg;
 447         spa_t           *io_spa;
 448         blkptr_t        *io_bp;
 449         blkptr_t        *io_bp_override;
 450         blkptr_t        io_bp_copy;
 451         list_t          io_parent_list;
 452         list_t          io_child_list;
 453         zio_t           *io_logical;
 454         zio_transform_t *io_transform_stack;
 455
 456         /* Callback info */
 457         zio_done_func_t *io_ready;
 458         zio_done_func_t *io_children_ready;
 459         zio_done_func_t *io_physdone;
 460         zio_done_func_t *io_done;
 461         void            *io_private;
 462         int64_t         io_prev_space_delta;    /* DMU private */
 463         blkptr_t        io_bp_orig;
 464         /* io_lsize != io_orig_size iff this is a raw write */
 465         uint64_t        io_lsize;
 466
 467         /* Data represented by this I/O */
 468         struct abd      *io_abd;
 469         struct abd      *io_orig_abd;
 470         uint64_t        io_size;
 471         uint64_t        io_orig_size;
 472
 473         /* Stuff for the vdev stack */
 474         vdev_t          *io_vd;
 475         void            *io_vsd;
 476         const zio_vsd_ops_t *io_vsd_ops;
 477         metaslab_class_t *io_metaslab_class;    /* dva throttle class */
 478
 479         uint64_t        io_offset;
 480         hrtime_t        io_timestamp;   /* submitted at */
 481         hrtime_t        io_queued_timestamp;
 482         hrtime_t        io_target_timestamp;
 483         hrtime_t        io_delta;       /* vdev queue service delta */
 484         hrtime_t        io_delay;       /* Device access time (disk or */
 485                                         /* file). */
 486         avl_node_t      io_queue_node;
 487         avl_node_t      io_offset_node;
 488         avl_node_t      io_alloc_node;
 489         zio_alloc_list_t        io_alloc_list;
 490
 491         /* Internal pipeline state */
 492         enum zio_flag   io_flags;
 493         enum zio_stage  io_stage;
 494         enum zio_stage  io_pipeline;
 495         enum zio_flag   io_orig_flags;
 496         enum zio_stage  io_orig_stage;
 497         enum zio_stage  io_orig_pipeline;
 498         enum zio_stage  io_pipeline_trace;
 499         int             io_error;
 500         int             io_child_error[ZIO_CHILD_TYPES];
 501         uint64_t        io_children[ZIO_CHILD_TYPES][ZIO_WAIT_TYPES];
 502         uint64_t        io_child_count;
 503         uint64_t        io_phys_children;
 504         uint64_t        io_parent_count;
 505         uint64_t        *io_stall;
 506         zio_t           *io_gang_leader;
 507         zio_gang_node_t *io_gang_tree;
 508         void            *io_executor;
 509         void            *io_waiter;
 510         kmutex_t        io_lock;
 511         kcondvar_t      io_cv;
 512         int             io_allocator;
 513
 514         /* FMA state */
 515         zio_cksum_report_t *io_cksum_report;
 516         uint64_t        io_ena;
 517
 518         /* Taskq dispatching state */
 519         taskq_ent_t     io_tqent;
 520 };
 521
 522 extern int zio_bookmark_compare(const void *, const void *);
 523
 524 extern zio_t *zio_null(zio_t *pio, spa_t *spa, vdev_t *vd,
 525     zio_done_func_t *done, void *private, enum zio_flag flags);
 526
 527 extern zio_t *zio_root(spa_t *spa,
 528     zio_done_func_t *done, void *private, enum zio_flag flags);
 529
 530 extern zio_t *zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp,
 531     struct abd *data, uint64_t lsize, zio_done_func_t *done, void *private,
 532     zio_priority_t priority, enum zio_flag flags, const zbookmark_phys_t *zb);
 533
 534 extern zio_t *zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
 535     struct abd *data, uint64_t size, uint64_t psize, const zio_prop_t *zp,
 536     zio_done_func_t *ready, zio_done_func_t *children_ready,
 537     zio_done_func_t *physdone, zio_done_func_t *done,
 538     void *private, zio_priority_t priority, enum zio_flag flags,
 539     const zbookmark_phys_t *zb);
 540
 541 extern zio_t *zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
 542     struct abd *data, uint64_t size, zio_done_func_t *done, void *private,
 543     zio_priority_t priority, enum zio_flag flags, zbookmark_phys_t *zb);
 544
 545 extern void zio_write_override(zio_t *zio, blkptr_t *bp, int copies,
 546     boolean_t nopwrite);
 547
 548 extern void zio_free(spa_t *spa, uint64_t txg, const blkptr_t *bp);
 549
 550 extern zio_t *zio_claim(zio_t *pio, spa_t *spa, uint64_t txg,
 551     const blkptr_t *bp,
 552     zio_done_func_t *done, void *private, enum zio_flag flags);
 553
 554 extern zio_t *zio_ioctl(zio_t *pio, spa_t *spa, vdev_t *vd, int cmd,
 555     zio_done_func_t *done, void *private, enum zio_flag flags);
 556
 557 extern zio_t *zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
 558     uint64_t size, struct abd *data, int checksum,
 559     zio_done_func_t *done, void *private, zio_priority_t priority,
 560     enum zio_flag flags, boolean_t labels);
 561
 562 extern zio_t *zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
 563     uint64_t size, struct abd *data, int checksum,
 564     zio_done_func_t *done, void *private, zio_priority_t priority,
 565     enum zio_flag flags, boolean_t labels);
 566
 567 extern zio_t *zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg,
 568     const blkptr_t *bp, enum zio_flag flags);
 569
 570 extern int zio_alloc_zil(spa_t *spa, objset_t *os, uint64_t txg,
 571     blkptr_t *new_bp, uint64_t size, boolean_t *slog);
 572 extern void zio_flush(zio_t *zio, vdev_t *vd);
 573 extern void zio_shrink(zio_t *zio, uint64_t size);
 574
 575 extern int zio_wait(zio_t *zio);
 576 extern void zio_nowait(zio_t *zio);
 577 extern void zio_execute(zio_t *zio);
 578 extern void zio_interrupt(zio_t *zio);
 579 extern void zio_delay_init(zio_t *zio);
 580 extern void zio_delay_interrupt(zio_t *zio);
 581 extern void zio_deadman(zio_t *zio, char *tag);
 582
 583 extern zio_t *zio_walk_parents(zio_t *cio, zio_link_t **);
 584 extern zio_t *zio_walk_children(zio_t *pio, zio_link_t **);
 585 extern zio_t *zio_unique_parent(zio_t *cio);
 586 extern void zio_add_child(zio_t *pio, zio_t *cio);
 587
 588 extern void *zio_buf_alloc(size_t size);
 589 extern void zio_buf_free(void *buf, size_t size);
 590 extern void *zio_data_buf_alloc(size_t size);
 591 extern void zio_data_buf_free(void *buf, size_t size);
 592
 593 extern void zio_push_transform(zio_t *zio, struct abd *abd, uint64_t size,
 594     uint64_t bufsize, zio_transform_func_t *transform);
 595 extern void zio_pop_transforms(zio_t *zio);
 596
 597 extern void zio_resubmit_stage_async(void *);
 598
 599 extern zio_t *zio_vdev_child_io(zio_t *zio, blkptr_t *bp, vdev_t *vd,
 600     uint64_t offset, struct abd *data, uint64_t size, int type,
 601     zio_priority_t priority, enum zio_flag flags,
 602     zio_done_func_t *done, void *private);
 603
 604 extern zio_t *zio_vdev_delegated_io(vdev_t *vd, uint64_t offset,
 605     struct abd *data, uint64_t size, zio_type_t type, zio_priority_t priority,
 606     enum zio_flag flags, zio_done_func_t *done, void *private);
 607
 608 extern void zio_vdev_io_bypass(zio_t *zio);
 609 extern void zio_vdev_io_reissue(zio_t *zio);
 610 extern void zio_vdev_io_redone(zio_t *zio);
 611
 612 extern void zio_change_priority(zio_t *pio, zio_priority_t priority);
 613
 614 extern void zio_checksum_verified(zio_t *zio);
 615 extern int zio_worst_error(int e1, int e2);
 616
 617 extern enum zio_checksum zio_checksum_select(enum zio_checksum child,
 618     enum zio_checksum parent);
 619 extern enum zio_checksum zio_checksum_dedup_select(spa_t *spa,
 620     enum zio_checksum child, enum zio_checksum parent);
 621 extern enum zio_compress zio_compress_select(spa_t *spa,
 622     enum zio_compress child, enum zio_compress parent);
 623
 624 extern void zio_suspend(spa_t *spa, zio_t *zio, zio_suspend_reason_t);
 625 extern int zio_resume(spa_t *spa);
 626 extern void zio_resume_wait(spa_t *spa);
 627
 628 /*
 629  * Initial setup and teardown.
 630  */
 631 extern void zio_init(void);
 632 extern void zio_fini(void);
 633
 634 /*
 635  * Fault injection
 636  */
 637 struct zinject_record;
 638 extern uint32_t zio_injection_enabled;
 639 extern int zio_inject_fault(char *name, int flags, int *id,
 640     struct zinject_record *record);
 641 extern int zio_inject_list_next(int *id, char *name, size_t buflen,
 642     struct zinject_record *record);
 643 extern int zio_clear_fault(int id);
 644 extern void zio_handle_panic_injection(spa_t *spa, char *tag, uint64_t type);
 645 extern int zio_handle_decrypt_injection(spa_t *spa, const zbookmark_phys_t *zb,
 646     uint64_t type, int error);
 647 extern int zio_handle_fault_injection(zio_t *zio, int error);
 648 extern int zio_handle_device_injection(vdev_t *vd, zio_t *zio, int error);
 649 extern int zio_handle_device_injections(vdev_t *vd, zio_t *zio, int err1,
 650     int err2);
 651 extern int zio_handle_label_injection(zio_t *zio, int error);
 652 extern void zio_handle_ignored_writes(zio_t *zio);
 653 extern hrtime_t zio_handle_io_delay(zio_t *zio);
 654
 655 /*
 656  * Checksum ereport functions
 657  */
 658 extern void zfs_ereport_start_checksum(spa_t *spa, vdev_t *vd,
 659     const zbookmark_phys_t *zb, struct zio *zio, uint64_t offset,
 660     uint64_t length, void *arg, struct zio_bad_cksum *info);
 661 extern void zfs_ereport_finish_checksum(zio_cksum_report_t *report,
 662     const abd_t *good_data, const abd_t *bad_data, boolean_t drop_if_identical);
 663
 664 extern void zfs_ereport_free_checksum(zio_cksum_report_t *report);
 665
 666 /* If we have the good data in hand, this function can be used */
 667 extern void zfs_ereport_post_checksum(spa_t *spa, vdev_t *vd,
 668     const zbookmark_phys_t *zb, struct zio *zio, uint64_t offset,
 669     uint64_t length, const abd_t *good_data, const abd_t *bad_data,
 670     struct zio_bad_cksum *info);
 671
 672 /* Called from spa_sync(), but primarily an injection handler */
 673 extern void spa_handle_ignored_writes(spa_t *spa);
 674
 675 /* zbookmark_phys functions */
 676 boolean_t zbookmark_subtree_completed(const struct dnode_phys *dnp,
 677     const zbookmark_phys_t *subtree_root, const zbookmark_phys_t *last_block);
 678 int zbookmark_compare(uint16_t dbss1, uint8_t ibs1, uint16_t dbss2,
 679     uint8_t ibs2, const zbookmark_phys_t *zb1, const zbookmark_phys_t *zb2);
 680
 681 #ifdef  __cplusplus
 682 }
 683 #endif
 684
 685 #endif  /* _ZIO_H */