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  */
  25 /*
  26  * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
  27  * Copyright (c) 2012 by Delphix. All rights reserved.
  28  */
  29
  30 #ifndef _ZIO_H
  31 #define _ZIO_H
  32
  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_FUNCTIONS
  84 };
  85
  86 #define ZIO_CHECKSUM_ON_VALUE   ZIO_CHECKSUM_FLETCHER_4
  87 #define ZIO_CHECKSUM_DEFAULT    ZIO_CHECKSUM_ON
  88
  89 #define ZIO_CHECKSUM_MASK       0xffULL
  90 #define ZIO_CHECKSUM_VERIFY     (1 << 8)
  91
  92 #define ZIO_DEDUPCHECKSUM       ZIO_CHECKSUM_SHA256
  93 #define ZIO_DEDUPDITTO_MIN      100
  94
  95 enum zio_compress {
  96         ZIO_COMPRESS_INHERIT = 0,
  97         ZIO_COMPRESS_ON,
  98         ZIO_COMPRESS_OFF,
  99         ZIO_COMPRESS_LZJB,
 100         ZIO_COMPRESS_EMPTY,
 101         ZIO_COMPRESS_GZIP_1,
 102         ZIO_COMPRESS_GZIP_2,
 103         ZIO_COMPRESS_GZIP_3,
 104         ZIO_COMPRESS_GZIP_4,
 105         ZIO_COMPRESS_GZIP_5,
 106         ZIO_COMPRESS_GZIP_6,
 107         ZIO_COMPRESS_GZIP_7,
 108         ZIO_COMPRESS_GZIP_8,
 109         ZIO_COMPRESS_GZIP_9,
 110         ZIO_COMPRESS_ZLE,
 111         ZIO_COMPRESS_FUNCTIONS
 112 };
 113
 114 #define ZIO_COMPRESS_ON_VALUE   ZIO_COMPRESS_LZJB
 115 #define ZIO_COMPRESS_DEFAULT    ZIO_COMPRESS_OFF
 116
 117 #define BOOTFS_COMPRESS_VALID(compress)                 \
 118         ((compress) == ZIO_COMPRESS_LZJB ||             \
 119         ((compress) == ZIO_COMPRESS_ON &&               \
 120         ZIO_COMPRESS_ON_VALUE == ZIO_COMPRESS_LZJB) ||  \
 121         (compress) == ZIO_COMPRESS_OFF)
 122
 123 /*
 124  * Default Linux timeout for a sd device.
 125  */
 126 #define ZIO_DELAY_MAX                   (30 * MILLISEC)
 127
 128 #define ZIO_FAILURE_MODE_WAIT           0
 129 #define ZIO_FAILURE_MODE_CONTINUE       1
 130 #define ZIO_FAILURE_MODE_PANIC          2
 131
 132 #define ZIO_PRIORITY_NOW                (zio_priority_table[0])
 133 #define ZIO_PRIORITY_SYNC_READ          (zio_priority_table[1])
 134 #define ZIO_PRIORITY_SYNC_WRITE         (zio_priority_table[2])
 135 #define ZIO_PRIORITY_LOG_WRITE          (zio_priority_table[3])
 136 #define ZIO_PRIORITY_CACHE_FILL         (zio_priority_table[4])
 137 #define ZIO_PRIORITY_AGG                (zio_priority_table[5])
 138 #define ZIO_PRIORITY_FREE               (zio_priority_table[6])
 139 #define ZIO_PRIORITY_ASYNC_WRITE        (zio_priority_table[7])
 140 #define ZIO_PRIORITY_ASYNC_READ         (zio_priority_table[8])
 141 #define ZIO_PRIORITY_RESILVER           (zio_priority_table[9])
 142 #define ZIO_PRIORITY_SCRUB              (zio_priority_table[10])
 143 #define ZIO_PRIORITY_DDT_PREFETCH       (zio_priority_table[11])
 144 #define ZIO_PRIORITY_TABLE_SIZE         12
 145
 146 #define ZIO_PIPELINE_CONTINUE           0x100
 147 #define ZIO_PIPELINE_STOP               0x101
 148
 149 enum zio_flag {
 150         /*
 151          * Flags inherited by gang, ddt, and vdev children,
 152          * and that must be equal for two zios to aggregate
 153          */
 154         ZIO_FLAG_DONT_AGGREGATE = 1 << 0,
 155         ZIO_FLAG_IO_REPAIR      = 1 << 1,
 156         ZIO_FLAG_SELF_HEAL      = 1 << 2,
 157         ZIO_FLAG_RESILVER       = 1 << 3,
 158         ZIO_FLAG_SCRUB          = 1 << 4,
 159         ZIO_FLAG_SCAN_THREAD    = 1 << 5,
 160
 161 #define ZIO_FLAG_AGG_INHERIT    (ZIO_FLAG_CANFAIL - 1)
 162
 163         /*
 164          * Flags inherited by ddt, gang, and vdev children.
 165          */
 166         ZIO_FLAG_CANFAIL        = 1 << 6,       /* must be first for INHERIT */
 167         ZIO_FLAG_SPECULATIVE    = 1 << 7,
 168         ZIO_FLAG_CONFIG_WRITER  = 1 << 8,
 169         ZIO_FLAG_DONT_RETRY     = 1 << 9,
 170         ZIO_FLAG_DONT_CACHE     = 1 << 10,
 171         ZIO_FLAG_NODATA         = 1 << 11,
 172         ZIO_FLAG_INDUCE_DAMAGE  = 1 << 12,
 173
 174 #define ZIO_FLAG_DDT_INHERIT    (ZIO_FLAG_IO_RETRY - 1)
 175 #define ZIO_FLAG_GANG_INHERIT   (ZIO_FLAG_IO_RETRY - 1)
 176
 177         /*
 178          * Flags inherited by vdev children.
 179          */
 180         ZIO_FLAG_IO_RETRY       = 1 << 13,      /* must be first for INHERIT */
 181         ZIO_FLAG_PROBE          = 1 << 14,
 182         ZIO_FLAG_TRYHARD        = 1 << 15,
 183         ZIO_FLAG_OPTIONAL       = 1 << 16,
 184
 185 #define ZIO_FLAG_VDEV_INHERIT   (ZIO_FLAG_DONT_QUEUE - 1)
 186
 187         /*
 188          * Flags not inherited by any children.
 189          */
 190         ZIO_FLAG_DONT_QUEUE     = 1 << 17,      /* must be first for INHERIT */
 191         ZIO_FLAG_DONT_PROPAGATE = 1 << 18,
 192         ZIO_FLAG_IO_BYPASS      = 1 << 19,
 193         ZIO_FLAG_IO_REWRITE     = 1 << 20,
 194         ZIO_FLAG_RAW            = 1 << 21,
 195         ZIO_FLAG_GANG_CHILD     = 1 << 22,
 196         ZIO_FLAG_DDT_CHILD      = 1 << 23,
 197         ZIO_FLAG_GODFATHER      = 1 << 24,
 198         ZIO_FLAG_FASTWRITE      = 1 << 25
 199 };
 200
 201 #define ZIO_FLAG_MUSTSUCCEED            0
 202
 203 #define ZIO_DDT_CHILD_FLAGS(zio)                                \
 204         (((zio)->io_flags & ZIO_FLAG_DDT_INHERIT) |             \
 205         ZIO_FLAG_DDT_CHILD | ZIO_FLAG_CANFAIL)
 206
 207 #define ZIO_GANG_CHILD_FLAGS(zio)                               \
 208         (((zio)->io_flags & ZIO_FLAG_GANG_INHERIT) |            \
 209         ZIO_FLAG_GANG_CHILD | ZIO_FLAG_CANFAIL)
 210
 211 #define ZIO_VDEV_CHILD_FLAGS(zio)                               \
 212         (((zio)->io_flags & ZIO_FLAG_VDEV_INHERIT) |            \
 213         ZIO_FLAG_CANFAIL)
 214
 215 enum zio_child {
 216         ZIO_CHILD_VDEV = 0,
 217         ZIO_CHILD_GANG,
 218         ZIO_CHILD_DDT,
 219         ZIO_CHILD_LOGICAL,
 220         ZIO_CHILD_TYPES
 221 };
 222
 223 enum zio_wait_type {
 224         ZIO_WAIT_READY = 0,
 225         ZIO_WAIT_DONE,
 226         ZIO_WAIT_TYPES
 227 };
 228
 229 /*
 230  * We'll take the unused errnos, 'EBADE' and 'EBADR' (from the Convergent
 231  * graveyard) to indicate checksum errors and fragmentation.
 232  */
 233 #define ECKSUM  EBADE
 234 #define EFRAGS  EBADR
 235
 236 typedef void zio_done_func_t(zio_t *zio);
 237
 238 extern uint8_t zio_priority_table[ZIO_PRIORITY_TABLE_SIZE];
 239 extern char *zio_type_name[ZIO_TYPES];
 240
 241 /*
 242  * A bookmark is a four-tuple <objset, object, level, blkid> that uniquely
 243  * identifies any block in the pool.  By convention, the meta-objset (MOS)
 244  * is objset 0, and the meta-dnode is object 0.  This covers all blocks
 245  * except root blocks and ZIL blocks, which are defined as follows:
 246  *
 247  * Root blocks (objset_phys_t) are object 0, level -1:  <objset, 0, -1, 0>.
 248  * ZIL blocks are bookmarked <objset, 0, -2, blkid == ZIL sequence number>.
 249  * dmu_sync()ed ZIL data blocks are bookmarked <objset, object, -2, blkid>.
 250  *
 251  * Note: this structure is called a bookmark because its original purpose
 252  * was to remember where to resume a pool-wide traverse.
 253  *
 254  * Note: this structure is passed between userland and the kernel.
 255  * Therefore it must not change size or alignment between 32/64 bit
 256  * compilation options.
 257  */
 258 typedef struct zbookmark {
 259         uint64_t        zb_objset;
 260         uint64_t        zb_object;
 261         int64_t         zb_level;
 262         uint64_t        zb_blkid;
 263 } zbookmark_t;
 264
 265 #define SET_BOOKMARK(zb, objset, object, level, blkid)  \
 266 {                                                       \
 267         (zb)->zb_objset = objset;                       \
 268         (zb)->zb_object = object;                       \
 269         (zb)->zb_level = level;                         \
 270         (zb)->zb_blkid = blkid;                         \
 271 }
 272
 273 #define ZB_DESTROYED_OBJSET     (-1ULL)
 274
 275 #define ZB_ROOT_OBJECT          (0ULL)
 276 #define ZB_ROOT_LEVEL           (-1LL)
 277 #define ZB_ROOT_BLKID           (0ULL)
 278
 279 #define ZB_ZIL_OBJECT           (0ULL)
 280 #define ZB_ZIL_LEVEL            (-2LL)
 281
 282 #define ZB_IS_ZERO(zb)                                          \
 283         ((zb)->zb_objset == 0 && (zb)->zb_object == 0 &&        \
 284         (zb)->zb_level == 0 && (zb)->zb_blkid == 0)
 285 #define ZB_IS_ROOT(zb)                          \
 286         ((zb)->zb_object == ZB_ROOT_OBJECT &&   \
 287         (zb)->zb_level == ZB_ROOT_LEVEL &&      \
 288         (zb)->zb_blkid == ZB_ROOT_BLKID)
 289
 290 typedef struct zio_prop {
 291         enum zio_checksum       zp_checksum;
 292         enum zio_compress       zp_compress;
 293         dmu_object_type_t       zp_type;
 294         uint8_t                 zp_level;
 295         uint8_t                 zp_copies;
 296         uint8_t                 zp_dedup;
 297         uint8_t                 zp_dedup_verify;
 298 } zio_prop_t;
 299
 300 typedef struct zio_cksum_report zio_cksum_report_t;
 301
 302 typedef void zio_cksum_finish_f(zio_cksum_report_t *rep,
 303     const void *good_data);
 304 typedef void zio_cksum_free_f(void *cbdata, size_t size);
 305
 306 struct zio_bad_cksum;                           /* defined in zio_checksum.h */
 307 struct dnode_phys;
 308
 309 struct zio_cksum_report {
 310         struct zio_cksum_report *zcr_next;
 311         nvlist_t                *zcr_ereport;
 312         nvlist_t                *zcr_detector;
 313         void                    *zcr_cbdata;
 314         size_t                  zcr_cbinfo;     /* passed to zcr_free() */
 315         uint64_t                zcr_align;
 316         uint64_t                zcr_length;
 317         zio_cksum_finish_f      *zcr_finish;
 318         zio_cksum_free_f        *zcr_free;
 319
 320         /* internal use only */
 321         struct zio_bad_cksum    *zcr_ckinfo;    /* information from failure */
 322 };
 323
 324 typedef void zio_vsd_cksum_report_f(zio_t *zio, zio_cksum_report_t *zcr,
 325     void *arg);
 326
 327 zio_vsd_cksum_report_f  zio_vsd_default_cksum_report;
 328
 329 typedef struct zio_vsd_ops {
 330         zio_done_func_t         *vsd_free;
 331         zio_vsd_cksum_report_f  *vsd_cksum_report;
 332 } zio_vsd_ops_t;
 333
 334 typedef struct zio_gang_node {
 335         zio_gbh_phys_t          *gn_gbh;
 336         struct zio_gang_node    *gn_child[SPA_GBH_NBLKPTRS];
 337 } zio_gang_node_t;
 338
 339 typedef zio_t *zio_gang_issue_func_t(zio_t *zio, blkptr_t *bp,
 340     zio_gang_node_t *gn, void *data);
 341
 342 typedef void zio_transform_func_t(zio_t *zio, void *data, uint64_t size);
 343
 344 typedef struct zio_transform {
 345         void                    *zt_orig_data;
 346         uint64_t                zt_orig_size;
 347         uint64_t                zt_bufsize;
 348         zio_transform_func_t    *zt_transform;
 349         struct zio_transform    *zt_next;
 350 } zio_transform_t;
 351
 352 typedef int zio_pipe_stage_t(zio_t *zio);
 353
 354 /*
 355  * The io_reexecute flags are distinct from io_flags because the child must
 356  * be able to propagate them to the parent.  The normal io_flags are local
 357  * to the zio, not protected by any lock, and not modifiable by children;
 358  * the reexecute flags are protected by io_lock, modifiable by children,
 359  * and always propagated -- even when ZIO_FLAG_DONT_PROPAGATE is set.
 360  */
 361 #define ZIO_REEXECUTE_NOW       0x01
 362 #define ZIO_REEXECUTE_SUSPEND   0x02
 363
 364 typedef struct zio_link {
 365         zio_t           *zl_parent;
 366         zio_t           *zl_child;
 367         list_node_t     zl_parent_node;
 368         list_node_t     zl_child_node;
 369 } zio_link_t;
 370
 371 struct zio {
 372         /* Core information about this I/O */
 373         zbookmark_t     io_bookmark;
 374         zio_prop_t      io_prop;
 375         zio_type_t      io_type;
 376         enum zio_child  io_child_type;
 377         int             io_cmd;
 378         uint8_t         io_priority;
 379         uint8_t         io_reexecute;
 380         uint8_t         io_state[ZIO_WAIT_TYPES];
 381         uint64_t        io_txg;
 382         spa_t           *io_spa;
 383         blkptr_t        *io_bp;
 384         blkptr_t        *io_bp_override;
 385         blkptr_t        io_bp_copy;
 386         list_t          io_parent_list;
 387         list_t          io_child_list;
 388         zio_link_t      *io_walk_link;
 389         zio_t           *io_logical;
 390         zio_transform_t *io_transform_stack;
 391
 392         /* Callback info */
 393         zio_done_func_t *io_ready;
 394         zio_done_func_t *io_done;
 395         void            *io_private;
 396         int64_t         io_prev_space_delta;    /* DMU private */
 397         blkptr_t        io_bp_orig;
 398
 399         /* Data represented by this I/O */
 400         void            *io_data;
 401         void            *io_orig_data;
 402         uint64_t        io_size;
 403         uint64_t        io_orig_size;
 404
 405         /* Stuff for the vdev stack */
 406         vdev_t          *io_vd;
 407         void            *io_vsd;
 408         const zio_vsd_ops_t *io_vsd_ops;
 409
 410         uint64_t        io_offset;
 411         uint64_t        io_deadline;
 412         avl_node_t      io_offset_node;
 413         avl_node_t      io_deadline_node;
 414         avl_tree_t      *io_vdev_tree;
 415
 416         /* Internal pipeline state */
 417         enum zio_flag   io_flags;
 418         enum zio_stage  io_stage;
 419         enum zio_stage  io_pipeline;
 420         enum zio_flag   io_orig_flags;
 421         enum zio_stage  io_orig_stage;
 422         enum zio_stage  io_orig_pipeline;
 423         uint64_t        io_delay;
 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_parent_count;
 429         uint64_t        *io_stall;
 430         zio_t           *io_gang_leader;
 431         zio_gang_node_t *io_gang_tree;
 432         void            *io_executor;
 433         void            *io_waiter;
 434         kmutex_t        io_lock;
 435         kcondvar_t      io_cv;
 436
 437         /* FMA state */
 438         zio_cksum_report_t *io_cksum_report;
 439         uint64_t        io_ena;
 440
 441         /* Taskq dispatching state */
 442         taskq_ent_t     io_tqent;
 443 };
 444
 445 extern zio_t *zio_null(zio_t *pio, spa_t *spa, vdev_t *vd,
 446     zio_done_func_t *done, void *private, enum zio_flag flags);
 447
 448 extern zio_t *zio_root(spa_t *spa,
 449     zio_done_func_t *done, void *private, enum zio_flag flags);
 450
 451 extern zio_t *zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, void *data,
 452     uint64_t size, zio_done_func_t *done, void *private,
 453     int priority, enum zio_flag flags, const zbookmark_t *zb);
 454
 455 extern zio_t *zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
 456     void *data, uint64_t size, const zio_prop_t *zp,
 457     zio_done_func_t *ready, zio_done_func_t *done, void *private,
 458     int priority, enum zio_flag flags, const zbookmark_t *zb);
 459
 460 extern zio_t *zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
 461     void *data, uint64_t size, zio_done_func_t *done, void *private,
 462     int priority, enum zio_flag flags, zbookmark_t *zb);
 463
 464 extern void zio_write_override(zio_t *zio, blkptr_t *bp, int copies);
 465
 466 extern void zio_free(spa_t *spa, uint64_t txg, const blkptr_t *bp);
 467
 468 extern zio_t *zio_claim(zio_t *pio, spa_t *spa, uint64_t txg,
 469     const blkptr_t *bp,
 470     zio_done_func_t *done, void *private, enum zio_flag flags);
 471
 472 extern zio_t *zio_ioctl(zio_t *pio, spa_t *spa, vdev_t *vd, int cmd,
 473     zio_done_func_t *done, void *private, int priority, enum zio_flag flags);
 474
 475 extern zio_t *zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
 476     uint64_t size, void *data, int checksum,
 477     zio_done_func_t *done, void *private, int priority, enum zio_flag flags,
 478     boolean_t labels);
 479
 480 extern zio_t *zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
 481     uint64_t size, void *data, int checksum,
 482     zio_done_func_t *done, void *private, int priority, enum zio_flag flags,
 483     boolean_t labels);
 484
 485 extern zio_t *zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg,
 486     const blkptr_t *bp, enum zio_flag flags);
 487
 488 extern int zio_alloc_zil(spa_t *spa, uint64_t txg, blkptr_t *new_bp,
 489     uint64_t size, boolean_t use_slog);
 490 extern void zio_free_zil(spa_t *spa, uint64_t txg, blkptr_t *bp);
 491 extern void zio_flush(zio_t *zio, vdev_t *vd);
 492 extern void zio_shrink(zio_t *zio, uint64_t size);
 493
 494 extern int zio_wait(zio_t *zio);
 495 extern void zio_nowait(zio_t *zio);
 496 extern void zio_execute(zio_t *zio);
 497 extern void zio_interrupt(zio_t *zio);
 498
 499 extern zio_t *zio_walk_parents(zio_t *cio);
 500 extern zio_t *zio_walk_children(zio_t *pio);
 501 extern zio_t *zio_unique_parent(zio_t *cio);
 502 extern void zio_add_child(zio_t *pio, zio_t *cio);
 503
 504 extern void *zio_buf_alloc(size_t size);
 505 extern void zio_buf_free(void *buf, size_t size);
 506 extern void *zio_data_buf_alloc(size_t size);
 507 extern void zio_data_buf_free(void *buf, size_t size);
 508 extern void *zio_vdev_alloc(void);
 509 extern void zio_vdev_free(void *buf);
 510
 511 extern void zio_resubmit_stage_async(void *);
 512
 513 extern zio_t *zio_vdev_child_io(zio_t *zio, blkptr_t *bp, vdev_t *vd,
 514     uint64_t offset, void *data, uint64_t size, int type, int priority,
 515     enum zio_flag flags, zio_done_func_t *done, void *private);
 516
 517 extern zio_t *zio_vdev_delegated_io(vdev_t *vd, uint64_t offset,
 518     void *data, uint64_t size, int type, int priority,
 519     enum zio_flag flags, zio_done_func_t *done, void *private);
 520
 521 extern void zio_vdev_io_bypass(zio_t *zio);
 522 extern void zio_vdev_io_reissue(zio_t *zio);
 523 extern void zio_vdev_io_redone(zio_t *zio);
 524
 525 extern void zio_checksum_verified(zio_t *zio);
 526 extern int zio_worst_error(int e1, int e2);
 527
 528 extern enum zio_checksum zio_checksum_select(enum zio_checksum child,
 529     enum zio_checksum parent);
 530 extern enum zio_checksum zio_checksum_dedup_select(spa_t *spa,
 531     enum zio_checksum child, enum zio_checksum parent);
 532 extern enum zio_compress zio_compress_select(enum zio_compress child,
 533     enum zio_compress parent);
 534
 535 extern void zio_suspend(spa_t *spa, zio_t *zio);
 536 extern int zio_resume(spa_t *spa);
 537 extern void zio_resume_wait(spa_t *spa);
 538
 539 /*
 540  * Initial setup and teardown.
 541  */
 542 extern void zio_init(void);
 543 extern void zio_fini(void);
 544
 545 /*
 546  * Fault injection
 547  */
 548 struct zinject_record;
 549 extern uint32_t zio_injection_enabled;
 550 extern int zio_inject_fault(char *name, int flags, int *id,
 551     struct zinject_record *record);
 552 extern int zio_inject_list_next(int *id, char *name, size_t buflen,
 553     struct zinject_record *record);
 554 extern int zio_clear_fault(int id);
 555 extern void zio_handle_panic_injection(spa_t *spa, char *tag, uint64_t type);
 556 extern int zio_handle_fault_injection(zio_t *zio, int error);
 557 extern int zio_handle_device_injection(vdev_t *vd, zio_t *zio, int error);
 558 extern int zio_handle_label_injection(zio_t *zio, int error);
 559 extern void zio_handle_ignored_writes(zio_t *zio);
 560
 561 /*
 562  * Checksum ereport functions
 563  */
 564 extern void zfs_ereport_start_checksum(spa_t *spa, vdev_t *vd, struct zio *zio,
 565     uint64_t offset, uint64_t length, void *arg, struct zio_bad_cksum *info);
 566 extern void zfs_ereport_finish_checksum(zio_cksum_report_t *report,
 567     const void *good_data, const void *bad_data, boolean_t drop_if_identical);
 568
 569 extern void zfs_ereport_send_interim_checksum(zio_cksum_report_t *report);
 570 extern void zfs_ereport_free_checksum(zio_cksum_report_t *report);
 571
 572 /* If we have the good data in hand, this function can be used */
 573 extern void zfs_ereport_post_checksum(spa_t *spa, vdev_t *vd,
 574     struct zio *zio, uint64_t offset, uint64_t length,
 575     const void *good_data, const void *bad_data, struct zio_bad_cksum *info);
 576
 577 /* Called from spa_sync(), but primarily an injection handler */
 578 extern void spa_handle_ignored_writes(spa_t *spa);
 579
 580 /* zbookmark functions */
 581 boolean_t zbookmark_is_before(const struct dnode_phys *dnp,
 582     const zbookmark_t *zb1, const zbookmark_t *zb2);
 583
 584 #ifdef  __cplusplus
 585 }
 586 #endif
 587
 588 #endif  /* _ZIO_H */