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, 2014 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/zfs_context.h>
  33 #include <sys/spa.h>
  34 #include <sys/txg.h>
  35 #include <sys/avl.h>
  36 #include <sys/fs/zfs.h>
  37 #include <sys/zio_impl.h>
  38
  39 #ifdef  __cplusplus
  40 extern "C" {
  41 #endif
  42
  43 /*
  44  * Embedded checksum
  45  */
  46 #define ZEC_MAGIC       0x210da7ab10c7a11ULL
  47
  48 typedef struct zio_eck {
  49         uint64_t        zec_magic;      /* for validation, endianness   */
  50         zio_cksum_t     zec_cksum;      /* 256-bit checksum             */
  51 } zio_eck_t;
  52
  53 /*
  54  * Gang block headers are self-checksumming and contain an array
  55  * of block pointers.
  56  */
  57 #define SPA_GANGBLOCKSIZE       SPA_MINBLOCKSIZE
  58 #define SPA_GBH_NBLKPTRS        ((SPA_GANGBLOCKSIZE - \
  59         sizeof (zio_eck_t)) / sizeof (blkptr_t))
  60 #define SPA_GBH_FILLER          ((SPA_GANGBLOCKSIZE - \
  61         sizeof (zio_eck_t) - \
  62         (SPA_GBH_NBLKPTRS * sizeof (blkptr_t))) /\
  63         sizeof (uint64_t))
  64
  65 typedef struct zio_gbh {
  66         blkptr_t                zg_blkptr[SPA_GBH_NBLKPTRS];
  67         uint64_t                zg_filler[SPA_GBH_FILLER];
  68         zio_eck_t               zg_tail;
  69 } zio_gbh_phys_t;
  70
  71 enum zio_checksum {
  72         ZIO_CHECKSUM_INHERIT = 0,
  73         ZIO_CHECKSUM_ON,
  74         ZIO_CHECKSUM_OFF,
  75         ZIO_CHECKSUM_LABEL,
  76         ZIO_CHECKSUM_GANG_HEADER,
  77         ZIO_CHECKSUM_ZILOG,
  78         ZIO_CHECKSUM_FLETCHER_2,
  79         ZIO_CHECKSUM_FLETCHER_4,
  80         ZIO_CHECKSUM_SHA256,
  81         ZIO_CHECKSUM_ZILOG2,
  82         ZIO_CHECKSUM_FUNCTIONS
  83 };
  84
  85 /*
  86  * The number of "legacy" compression functions which can be set on individual
  87  * objects.
  88  */
  89 #define ZIO_CHECKSUM_LEGACY_FUNCTIONS ZIO_CHECKSUM_ZILOG2
  90
  91 #define ZIO_CHECKSUM_ON_VALUE   ZIO_CHECKSUM_FLETCHER_4
  92 #define ZIO_CHECKSUM_DEFAULT    ZIO_CHECKSUM_ON
  93
  94 #define ZIO_CHECKSUM_MASK       0xffULL
  95 #define ZIO_CHECKSUM_VERIFY     (1 << 8)
  96
  97 #define ZIO_DEDUPCHECKSUM       ZIO_CHECKSUM_SHA256
  98 #define ZIO_DEDUPDITTO_MIN      100
  99
 100 enum zio_compress {
 101         ZIO_COMPRESS_INHERIT = 0,
 102         ZIO_COMPRESS_ON,
 103         ZIO_COMPRESS_OFF,
 104         ZIO_COMPRESS_LZJB,
 105         ZIO_COMPRESS_EMPTY,
 106         ZIO_COMPRESS_GZIP_1,
 107         ZIO_COMPRESS_GZIP_2,
 108         ZIO_COMPRESS_GZIP_3,
 109         ZIO_COMPRESS_GZIP_4,
 110         ZIO_COMPRESS_GZIP_5,
 111         ZIO_COMPRESS_GZIP_6,
 112         ZIO_COMPRESS_GZIP_7,
 113         ZIO_COMPRESS_GZIP_8,
 114         ZIO_COMPRESS_GZIP_9,
 115         ZIO_COMPRESS_ZLE,
 116         ZIO_COMPRESS_LZ4,
 117         ZIO_COMPRESS_FUNCTIONS
 118 };
 119
 120 /*
 121  * The number of "legacy" compression functions which can be set on individual
 122  * objects.
 123  */
 124 #define ZIO_COMPRESS_LEGACY_FUNCTIONS ZIO_COMPRESS_LZ4
 125
 126 /*
 127  * The meaning of "compress = on" selected by the compression features enabled
 128  * on a given pool.
 129  */
 130 #define ZIO_COMPRESS_LEGACY_ON_VALUE    ZIO_COMPRESS_LZJB
 131 #define ZIO_COMPRESS_LZ4_ON_VALUE       ZIO_COMPRESS_LZ4
 132
 133 #define ZIO_COMPRESS_DEFAULT            ZIO_COMPRESS_OFF
 134
 135 #define BOOTFS_COMPRESS_VALID(compress)                 \
 136         ((compress) == ZIO_COMPRESS_LZJB ||             \
 137         (compress) == ZIO_COMPRESS_LZ4 ||               \
 138         (compress) == ZIO_COMPRESS_ON ||                \
 139         (compress) == ZIO_COMPRESS_OFF)
 140
 141 /*
 142  * Default Linux timeout for a sd device.
 143  */
 144 #define ZIO_DELAY_MAX                   (30 * MILLISEC)
 145
 146 #define ZIO_FAILURE_MODE_WAIT           0
 147 #define ZIO_FAILURE_MODE_CONTINUE       1
 148 #define ZIO_FAILURE_MODE_PANIC          2
 149
 150 typedef enum zio_priority {
 151         ZIO_PRIORITY_SYNC_READ,
 152         ZIO_PRIORITY_SYNC_WRITE,        /* ZIL */
 153         ZIO_PRIORITY_ASYNC_READ,        /* prefetch */
 154         ZIO_PRIORITY_ASYNC_WRITE,       /* spa_sync() */
 155         ZIO_PRIORITY_SCRUB,             /* asynchronous scrub/resilver reads */
 156         ZIO_PRIORITY_NUM_QUEUEABLE,
 157
 158         ZIO_PRIORITY_NOW                /* non-queued i/os (e.g. free) */
 159 } zio_priority_t;
 160
 161 enum zio_flag {
 162         /*
 163          * Flags inherited by gang, ddt, and vdev children,
 164          * and that must be equal for two zios to aggregate
 165          */
 166         ZIO_FLAG_DONT_AGGREGATE = 1 << 0,
 167         ZIO_FLAG_IO_REPAIR      = 1 << 1,
 168         ZIO_FLAG_SELF_HEAL      = 1 << 2,
 169         ZIO_FLAG_RESILVER       = 1 << 3,
 170         ZIO_FLAG_SCRUB          = 1 << 4,
 171         ZIO_FLAG_SCAN_THREAD    = 1 << 5,
 172         ZIO_FLAG_PHYSICAL       = 1 << 6,
 173
 174 #define ZIO_FLAG_AGG_INHERIT    (ZIO_FLAG_CANFAIL - 1)
 175
 176         /*
 177          * Flags inherited by ddt, gang, and vdev children.
 178          */
 179         ZIO_FLAG_CANFAIL        = 1 << 7,       /* must be first for INHERIT */
 180         ZIO_FLAG_SPECULATIVE    = 1 << 8,
 181         ZIO_FLAG_CONFIG_WRITER  = 1 << 9,
 182         ZIO_FLAG_DONT_RETRY     = 1 << 10,
 183         ZIO_FLAG_DONT_CACHE     = 1 << 11,
 184         ZIO_FLAG_NODATA         = 1 << 12,
 185         ZIO_FLAG_INDUCE_DAMAGE  = 1 << 13,
 186
 187 #define ZIO_FLAG_DDT_INHERIT    (ZIO_FLAG_IO_RETRY - 1)
 188 #define ZIO_FLAG_GANG_INHERIT   (ZIO_FLAG_IO_RETRY - 1)
 189
 190         /*
 191          * Flags inherited by vdev children.
 192          */
 193         ZIO_FLAG_IO_RETRY       = 1 << 14,      /* must be first for INHERIT */
 194         ZIO_FLAG_PROBE          = 1 << 15,
 195         ZIO_FLAG_TRYHARD        = 1 << 16,
 196         ZIO_FLAG_OPTIONAL       = 1 << 17,
 197
 198 #define ZIO_FLAG_VDEV_INHERIT   (ZIO_FLAG_DONT_QUEUE - 1)
 199
 200         /*
 201          * Flags not inherited by any children.
 202          */
 203         ZIO_FLAG_DONT_QUEUE     = 1 << 18,      /* must be first for INHERIT */
 204         ZIO_FLAG_DONT_PROPAGATE = 1 << 19,
 205         ZIO_FLAG_IO_BYPASS      = 1 << 20,
 206         ZIO_FLAG_IO_REWRITE     = 1 << 21,
 207         ZIO_FLAG_RAW            = 1 << 22,
 208         ZIO_FLAG_GANG_CHILD     = 1 << 23,
 209         ZIO_FLAG_DDT_CHILD      = 1 << 24,
 210         ZIO_FLAG_GODFATHER      = 1 << 25,
 211         ZIO_FLAG_NOPWRITE       = 1 << 26,
 212         ZIO_FLAG_REEXECUTED     = 1 << 27,
 213         ZIO_FLAG_DELEGATED      = 1 << 28,
 214         ZIO_FLAG_FASTWRITE      = 1 << 29,
 215 };
 216
 217 #define ZIO_FLAG_MUSTSUCCEED            0
 218
 219 #define ZIO_DDT_CHILD_FLAGS(zio)                                \
 220         (((zio)->io_flags & ZIO_FLAG_DDT_INHERIT) |             \
 221         ZIO_FLAG_DDT_CHILD | ZIO_FLAG_CANFAIL)
 222
 223 #define ZIO_GANG_CHILD_FLAGS(zio)                               \
 224         (((zio)->io_flags & ZIO_FLAG_GANG_INHERIT) |            \
 225         ZIO_FLAG_GANG_CHILD | ZIO_FLAG_CANFAIL)
 226
 227 #define ZIO_VDEV_CHILD_FLAGS(zio)                               \
 228         (((zio)->io_flags & ZIO_FLAG_VDEV_INHERIT) |            \
 229         ZIO_FLAG_CANFAIL)
 230
 231 enum zio_child {
 232         ZIO_CHILD_VDEV = 0,
 233         ZIO_CHILD_GANG,
 234         ZIO_CHILD_DDT,
 235         ZIO_CHILD_LOGICAL,
 236         ZIO_CHILD_TYPES
 237 };
 238
 239 enum zio_wait_type {
 240         ZIO_WAIT_READY = 0,
 241         ZIO_WAIT_DONE,
 242         ZIO_WAIT_TYPES
 243 };
 244
 245 /*
 246  * We'll take the unused errnos, 'EBADE' and 'EBADR' (from the Convergent
 247  * graveyard) to indicate checksum errors and fragmentation.
 248  */
 249 #define ECKSUM  EBADE
 250 #define EFRAGS  EBADR
 251
 252 typedef void zio_done_func_t(zio_t *zio);
 253
 254 extern const char *zio_type_name[ZIO_TYPES];
 255
 256 /*
 257  * A bookmark is a four-tuple <objset, object, level, blkid> that uniquely
 258  * identifies any block in the pool.  By convention, the meta-objset (MOS)
 259  * is objset 0, and the meta-dnode is object 0.  This covers all blocks
 260  * except root blocks and ZIL blocks, which are defined as follows:
 261  *
 262  * Root blocks (objset_phys_t) are object 0, level -1:  <objset, 0, -1, 0>.
 263  * ZIL blocks are bookmarked <objset, 0, -2, blkid == ZIL sequence number>.
 264  * dmu_sync()ed ZIL data blocks are bookmarked <objset, object, -2, blkid>.
 265  *
 266  * Note: this structure is called a bookmark because its original purpose
 267  * was to remember where to resume a pool-wide traverse.
 268  *
 269  * Note: this structure is passed between userland and the kernel, and is
 270  * stored on disk (by virtue of being incorporated into other on-disk
 271  * structures, e.g. dsl_scan_phys_t).
 272  */
 273 struct zbookmark_phys {
 274         uint64_t        zb_objset;
 275         uint64_t        zb_object;
 276         int64_t         zb_level;
 277         uint64_t        zb_blkid;
 278 };
 279
 280 #define SET_BOOKMARK(zb, objset, object, level, blkid)  \
 281 {                                                       \
 282         (zb)->zb_objset = objset;                       \
 283         (zb)->zb_object = object;                       \
 284         (zb)->zb_level = level;                         \
 285         (zb)->zb_blkid = blkid;                         \
 286 }
 287
 288 #define ZB_DESTROYED_OBJSET     (-1ULL)
 289
 290 #define ZB_ROOT_OBJECT          (0ULL)
 291 #define ZB_ROOT_LEVEL           (-1LL)
 292 #define ZB_ROOT_BLKID           (0ULL)
 293
 294 #define ZB_ZIL_OBJECT           (0ULL)
 295 #define ZB_ZIL_LEVEL            (-2LL)
 296
 297 #define ZB_IS_ZERO(zb)                                          \
 298         ((zb)->zb_objset == 0 && (zb)->zb_object == 0 &&        \
 299         (zb)->zb_level == 0 && (zb)->zb_blkid == 0)
 300 #define ZB_IS_ROOT(zb)                          \
 301         ((zb)->zb_object == ZB_ROOT_OBJECT &&   \
 302         (zb)->zb_level == ZB_ROOT_LEVEL &&      \
 303         (zb)->zb_blkid == ZB_ROOT_BLKID)
 304
 305 typedef struct zio_prop {
 306         enum zio_checksum       zp_checksum;
 307         enum zio_compress       zp_compress;
 308         dmu_object_type_t       zp_type;
 309         uint8_t                 zp_level;
 310         uint8_t                 zp_copies;
 311         boolean_t               zp_dedup;
 312         boolean_t               zp_dedup_verify;
 313         boolean_t               zp_nopwrite;
 314 } zio_prop_t;
 315
 316 typedef struct zio_cksum_report zio_cksum_report_t;
 317
 318 typedef void zio_cksum_finish_f(zio_cksum_report_t *rep,
 319     const void *good_data);
 320 typedef void zio_cksum_free_f(void *cbdata, size_t size);
 321
 322 struct zio_bad_cksum;                           /* defined in zio_checksum.h */
 323 struct dnode_phys;
 324
 325 struct zio_cksum_report {
 326         struct zio_cksum_report *zcr_next;
 327         nvlist_t                *zcr_ereport;
 328         nvlist_t                *zcr_detector;
 329         void                    *zcr_cbdata;
 330         size_t                  zcr_cbinfo;     /* passed to zcr_free() */
 331         uint64_t                zcr_align;
 332         uint64_t                zcr_length;
 333         zio_cksum_finish_f      *zcr_finish;
 334         zio_cksum_free_f        *zcr_free;
 335
 336         /* internal use only */
 337         struct zio_bad_cksum    *zcr_ckinfo;    /* information from failure */
 338 };
 339
 340 typedef void zio_vsd_cksum_report_f(zio_t *zio, zio_cksum_report_t *zcr,
 341     void *arg);
 342
 343 zio_vsd_cksum_report_f  zio_vsd_default_cksum_report;
 344
 345 typedef struct zio_vsd_ops {
 346         zio_done_func_t         *vsd_free;
 347         zio_vsd_cksum_report_f  *vsd_cksum_report;
 348 } zio_vsd_ops_t;
 349
 350 typedef struct zio_gang_node {
 351         zio_gbh_phys_t          *gn_gbh;
 352         struct zio_gang_node    *gn_child[SPA_GBH_NBLKPTRS];
 353 } zio_gang_node_t;
 354
 355 typedef zio_t *zio_gang_issue_func_t(zio_t *zio, blkptr_t *bp,
 356     zio_gang_node_t *gn, void *data);
 357
 358 typedef void zio_transform_func_t(zio_t *zio, void *data, uint64_t size);
 359
 360 typedef struct zio_transform {
 361         void                    *zt_orig_data;
 362         uint64_t                zt_orig_size;
 363         uint64_t                zt_bufsize;
 364         zio_transform_func_t    *zt_transform;
 365         struct zio_transform    *zt_next;
 366 } zio_transform_t;
 367
 368 typedef int zio_pipe_stage_t(zio_t *zio);
 369
 370 /*
 371  * The io_reexecute flags are distinct from io_flags because the child must
 372  * be able to propagate them to the parent.  The normal io_flags are local
 373  * to the zio, not protected by any lock, and not modifiable by children;
 374  * the reexecute flags are protected by io_lock, modifiable by children,
 375  * and always propagated -- even when ZIO_FLAG_DONT_PROPAGATE is set.
 376  */
 377 #define ZIO_REEXECUTE_NOW       0x01
 378 #define ZIO_REEXECUTE_SUSPEND   0x02
 379
 380 typedef struct zio_link {
 381         zio_t           *zl_parent;
 382         zio_t           *zl_child;
 383         list_node_t     zl_parent_node;
 384         list_node_t     zl_child_node;
 385 } zio_link_t;
 386
 387 struct zio {
 388         /* Core information about this I/O */
 389         zbookmark_phys_t        io_bookmark;
 390         zio_prop_t      io_prop;
 391         zio_type_t      io_type;
 392         enum zio_child  io_child_type;
 393         int             io_cmd;
 394         zio_priority_t  io_priority;
 395         uint8_t         io_reexecute;
 396         uint8_t         io_state[ZIO_WAIT_TYPES];
 397         uint64_t        io_txg;
 398         spa_t           *io_spa;
 399         blkptr_t        *io_bp;
 400         blkptr_t        *io_bp_override;
 401         blkptr_t        io_bp_copy;
 402         list_t          io_parent_list;
 403         list_t          io_child_list;
 404         zio_link_t      *io_walk_link;
 405         zio_t           *io_logical;
 406         zio_transform_t *io_transform_stack;
 407
 408         /* Callback info */
 409         zio_done_func_t *io_ready;
 410         zio_done_func_t *io_physdone;
 411         zio_done_func_t *io_done;
 412         void            *io_private;
 413         int64_t         io_prev_space_delta;    /* DMU private */
 414         blkptr_t        io_bp_orig;
 415
 416         /* Data represented by this I/O */
 417         void            *io_data;
 418         void            *io_orig_data;
 419         uint64_t        io_size;
 420         uint64_t        io_orig_size;
 421
 422         /* Stuff for the vdev stack */
 423         vdev_t          *io_vd;
 424         void            *io_vsd;
 425         const zio_vsd_ops_t *io_vsd_ops;
 426
 427         uint64_t        io_offset;
 428         hrtime_t        io_timestamp;   /* submitted at */
 429         hrtime_t        io_delta;       /* vdev queue service delta */
 430         uint64_t        io_delay;       /* vdev disk service delta (ticks) */
 431         avl_node_t      io_queue_node;
 432         avl_node_t      io_offset_node;
 433
 434         /* Internal pipeline state */
 435         enum zio_flag   io_flags;
 436         enum zio_stage  io_stage;
 437         enum zio_stage  io_pipeline;
 438         enum zio_flag   io_orig_flags;
 439         enum zio_stage  io_orig_stage;
 440         enum zio_stage  io_orig_pipeline;
 441         int             io_error;
 442         int             io_child_error[ZIO_CHILD_TYPES];
 443         uint64_t        io_children[ZIO_CHILD_TYPES][ZIO_WAIT_TYPES];
 444         uint64_t        io_child_count;
 445         uint64_t        io_phys_children;
 446         uint64_t        io_parent_count;
 447         uint64_t        *io_stall;
 448         zio_t           *io_gang_leader;
 449         zio_gang_node_t *io_gang_tree;
 450         void            *io_executor;
 451         void            *io_waiter;
 452         kmutex_t        io_lock;
 453         kcondvar_t      io_cv;
 454
 455         /* FMA state */
 456         zio_cksum_report_t *io_cksum_report;
 457         uint64_t        io_ena;
 458
 459         /* Taskq dispatching state */
 460         taskq_ent_t     io_tqent;
 461 };
 462
 463 extern zio_t *zio_null(zio_t *pio, spa_t *spa, vdev_t *vd,
 464     zio_done_func_t *done, void *private, enum zio_flag flags);
 465
 466 extern zio_t *zio_root(spa_t *spa,
 467     zio_done_func_t *done, void *private, enum zio_flag flags);
 468
 469 extern zio_t *zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, void *data,
 470     uint64_t size, zio_done_func_t *done, void *private,
 471     zio_priority_t priority, enum zio_flag flags, const zbookmark_phys_t *zb);
 472
 473 extern zio_t *zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
 474     void *data, uint64_t size, const zio_prop_t *zp,
 475     zio_done_func_t *ready, zio_done_func_t *physdone, zio_done_func_t *done,
 476     void *private,
 477     zio_priority_t priority, enum zio_flag flags, const zbookmark_phys_t *zb);
 478
 479 extern zio_t *zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
 480     void *data, uint64_t size, zio_done_func_t *done, void *private,
 481     zio_priority_t priority, enum zio_flag flags, zbookmark_phys_t *zb);
 482
 483 extern void zio_write_override(zio_t *zio, blkptr_t *bp, int copies,
 484     boolean_t nopwrite);
 485
 486 extern void zio_free(spa_t *spa, uint64_t txg, const blkptr_t *bp);
 487
 488 extern zio_t *zio_claim(zio_t *pio, spa_t *spa, uint64_t txg,
 489     const blkptr_t *bp,
 490     zio_done_func_t *done, void *private, enum zio_flag flags);
 491
 492 extern zio_t *zio_ioctl(zio_t *pio, spa_t *spa, vdev_t *vd, int cmd,
 493     zio_done_func_t *done, void *private, enum zio_flag flags);
 494
 495 extern zio_t *zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
 496     uint64_t size, void *data, int checksum,
 497     zio_done_func_t *done, void *private, zio_priority_t priority,
 498     enum zio_flag flags, boolean_t labels);
 499
 500 extern zio_t *zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
 501     uint64_t size, void *data, int checksum,
 502     zio_done_func_t *done, void *private, zio_priority_t priority,
 503     enum zio_flag flags, boolean_t labels);
 504
 505 extern zio_t *zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg,
 506     const blkptr_t *bp, enum zio_flag flags);
 507
 508 extern int zio_alloc_zil(spa_t *spa, uint64_t txg, blkptr_t *new_bp,
 509     uint64_t size, boolean_t use_slog);
 510 extern void zio_free_zil(spa_t *spa, uint64_t txg, blkptr_t *bp);
 511 extern void zio_flush(zio_t *zio, vdev_t *vd);
 512 extern void zio_shrink(zio_t *zio, uint64_t size);
 513
 514 extern int zio_wait(zio_t *zio);
 515 extern void zio_nowait(zio_t *zio);
 516 extern void zio_execute(zio_t *zio);
 517 extern void zio_interrupt(zio_t *zio);
 518
 519 extern zio_t *zio_walk_parents(zio_t *cio);
 520 extern zio_t *zio_walk_children(zio_t *pio);
 521 extern zio_t *zio_unique_parent(zio_t *cio);
 522 extern void zio_add_child(zio_t *pio, zio_t *cio);
 523
 524 extern void *zio_buf_alloc(size_t size);
 525 extern void zio_buf_free(void *buf, size_t size);
 526 extern void *zio_data_buf_alloc(size_t size);
 527 extern void zio_data_buf_free(void *buf, size_t size);
 528 extern void *zio_buf_alloc_flags(size_t size, int flags);
 529
 530 extern void zio_resubmit_stage_async(void *);
 531
 532 extern zio_t *zio_vdev_child_io(zio_t *zio, blkptr_t *bp, vdev_t *vd,
 533     uint64_t offset, void *data, uint64_t size, int type,
 534     zio_priority_t priority, enum zio_flag flags,
 535     zio_done_func_t *done, void *private);
 536
 537 extern zio_t *zio_vdev_delegated_io(vdev_t *vd, uint64_t offset,
 538     void *data, uint64_t size, int type, zio_priority_t priority,
 539     enum zio_flag flags, zio_done_func_t *done, void *private);
 540
 541 extern void zio_vdev_io_bypass(zio_t *zio);
 542 extern void zio_vdev_io_reissue(zio_t *zio);
 543 extern void zio_vdev_io_redone(zio_t *zio);
 544
 545 extern void zio_checksum_verified(zio_t *zio);
 546 extern int zio_worst_error(int e1, int e2);
 547
 548 extern enum zio_checksum zio_checksum_select(enum zio_checksum child,
 549     enum zio_checksum parent);
 550 extern enum zio_checksum zio_checksum_dedup_select(spa_t *spa,
 551     enum zio_checksum child, enum zio_checksum parent);
 552 extern enum zio_compress zio_compress_select(spa_t *spa,
 553     enum zio_compress child, enum zio_compress parent);
 554
 555 extern void zio_suspend(spa_t *spa, zio_t *zio);
 556 extern int zio_resume(spa_t *spa);
 557 extern void zio_resume_wait(spa_t *spa);
 558
 559 /*
 560  * Initial setup and teardown.
 561  */
 562 extern void zio_init(void);
 563 extern void zio_fini(void);
 564
 565 /*
 566  * Fault injection
 567  */
 568 struct zinject_record;
 569 extern uint32_t zio_injection_enabled;
 570 extern int zio_inject_fault(char *name, int flags, int *id,
 571     struct zinject_record *record);
 572 extern int zio_inject_list_next(int *id, char *name, size_t buflen,
 573     struct zinject_record *record);
 574 extern int zio_clear_fault(int id);
 575 extern void zio_handle_panic_injection(spa_t *spa, char *tag, uint64_t type);
 576 extern int zio_handle_fault_injection(zio_t *zio, int error);
 577 extern int zio_handle_device_injection(vdev_t *vd, zio_t *zio, int error);
 578 extern int zio_handle_label_injection(zio_t *zio, int error);
 579 extern void zio_handle_ignored_writes(zio_t *zio);
 580 extern uint64_t zio_handle_io_delay(zio_t *zio);
 581
 582 /*
 583  * Checksum ereport functions
 584  */
 585 extern void zfs_ereport_start_checksum(spa_t *spa, vdev_t *vd, struct zio *zio,
 586     uint64_t offset, uint64_t length, void *arg, struct zio_bad_cksum *info);
 587 extern void zfs_ereport_finish_checksum(zio_cksum_report_t *report,
 588     const void *good_data, const void *bad_data, boolean_t drop_if_identical);
 589
 590 extern void zfs_ereport_send_interim_checksum(zio_cksum_report_t *report);
 591 extern void zfs_ereport_free_checksum(zio_cksum_report_t *report);
 592
 593 /* If we have the good data in hand, this function can be used */
 594 extern void zfs_ereport_post_checksum(spa_t *spa, vdev_t *vd,
 595     struct zio *zio, uint64_t offset, uint64_t length,
 596     const void *good_data, const void *bad_data, struct zio_bad_cksum *info);
 597
 598 /* Called from spa_sync(), but primarily an injection handler */
 599 extern void spa_handle_ignored_writes(spa_t *spa);
 600
 601 /* zbookmark_phys functions */
 602 boolean_t zbookmark_is_before(const struct dnode_phys *dnp,
 603     const zbookmark_phys_t *zb1, const zbookmark_phys_t *zb2);
 604
 605 #ifdef  __cplusplus
 606 }
 607 #endif
 608
 609 #endif  /* _ZIO_H */