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