/*

 * CDDL HEADER START

 *

 * The contents of this file are subject to the terms of the

 * Common Development and Distribution License (the "License").

 * You may not use this file except in compliance with the License.

 *

 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE

 * or http://www.opensolaris.org/os/licensing.

 * See the License for the specific language governing permissions

 * and limitations under the License.

 *

 * When distributing Covered Code, include this CDDL HEADER in each

 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.

 * If applicable, add the following below this CDDL HEADER, with the

 * fields enclosed by brackets "[]" replaced with your own identifying

 * information: Portions Copyright [yyyy] [name of copyright owner]

 *

 * CDDL HEADER END

 */

/*

 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.

 */

/*

 * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.

 */

#ifndef _ZIO_H

#define	_ZIO_H

#include <sys/zfs_context.h>

#include <sys/spa.h>

#include <sys/txg.h>

#include <sys/avl.h>

#include <sys/fs/zfs.h>

#include <sys/zio_impl.h>

#ifdef	__cplusplus

extern "C" {

#endif

/*

 * Embedded checksum

 */

#define	ZEC_MAGIC	0x210da7ab10c7a11ULL

typedef struct zio_eck {

	uint64_t	zec_magic;	/* for validation, endianness	*/

	zio_cksum_t	zec_cksum;	/* 256-bit checksum		*/

} zio_eck_t;

/*

 * Gang block headers are self-checksumming and contain an array

 * of block pointers.

 */

#define	SPA_GANGBLOCKSIZE	SPA_MINBLOCKSIZE

#define	SPA_GBH_NBLKPTRS	((SPA_GANGBLOCKSIZE - \

	sizeof (zio_eck_t)) / sizeof (blkptr_t))

#define	SPA_GBH_FILLER		((SPA_GANGBLOCKSIZE - \

	sizeof (zio_eck_t) - \

	(SPA_GBH_NBLKPTRS * sizeof (blkptr_t))) /\

	sizeof (uint64_t))

typedef struct zio_gbh {

	blkptr_t		zg_blkptr[SPA_GBH_NBLKPTRS];

	uint64_t		zg_filler[SPA_GBH_FILLER];

	zio_eck_t		zg_tail;

} zio_gbh_phys_t;

enum zio_checksum {

	ZIO_CHECKSUM_INHERIT = 0,

	ZIO_CHECKSUM_ON,

	ZIO_CHECKSUM_OFF,

	ZIO_CHECKSUM_LABEL,

	ZIO_CHECKSUM_GANG_HEADER,

	ZIO_CHECKSUM_ZILOG,

	ZIO_CHECKSUM_FLETCHER_2,

	ZIO_CHECKSUM_FLETCHER_4,

	ZIO_CHECKSUM_SHA256,

	ZIO_CHECKSUM_ZILOG2,

	ZIO_CHECKSUM_FUNCTIONS

};

#define	ZIO_CHECKSUM_ON_VALUE	ZIO_CHECKSUM_FLETCHER_4

#define	ZIO_CHECKSUM_DEFAULT	ZIO_CHECKSUM_ON

#define	ZIO_CHECKSUM_MASK	0xffULL

#define	ZIO_CHECKSUM_VERIFY	(1 << 8)

#define	ZIO_DEDUPCHECKSUM	ZIO_CHECKSUM_SHA256

#define	ZIO_DEDUPDITTO_MIN	100

enum zio_compress {

	ZIO_COMPRESS_INHERIT = 0,

	ZIO_COMPRESS_ON,

	ZIO_COMPRESS_OFF,

	ZIO_COMPRESS_LZJB,

	ZIO_COMPRESS_EMPTY,

	ZIO_COMPRESS_GZIP_1,

	ZIO_COMPRESS_GZIP_2,

	ZIO_COMPRESS_GZIP_3,

	ZIO_COMPRESS_GZIP_4,

	ZIO_COMPRESS_GZIP_5,

	ZIO_COMPRESS_GZIP_6,

	ZIO_COMPRESS_GZIP_7,

	ZIO_COMPRESS_GZIP_8,

	ZIO_COMPRESS_GZIP_9,

	ZIO_COMPRESS_ZLE,

	ZIO_COMPRESS_FUNCTIONS

};

#define	ZIO_COMPRESS_ON_VALUE	ZIO_COMPRESS_LZJB

#define	ZIO_COMPRESS_DEFAULT	ZIO_COMPRESS_OFF

#define	BOOTFS_COMPRESS_VALID(compress)			\

	((compress) == ZIO_COMPRESS_LZJB ||		\

	((compress) == ZIO_COMPRESS_ON &&		\

	ZIO_COMPRESS_ON_VALUE == ZIO_COMPRESS_LZJB) ||	\

	(compress) == ZIO_COMPRESS_OFF)

#define	ZIO_FAILURE_MODE_WAIT		0

#define	ZIO_FAILURE_MODE_CONTINUE	1

#define	ZIO_FAILURE_MODE_PANIC		2

#define	ZIO_PRIORITY_NOW		(zio_priority_table[0])

#define	ZIO_PRIORITY_SYNC_READ		(zio_priority_table[1])

#define	ZIO_PRIORITY_SYNC_WRITE		(zio_priority_table[2])

#define	ZIO_PRIORITY_LOG_WRITE		(zio_priority_table[3])

#define	ZIO_PRIORITY_CACHE_FILL		(zio_priority_table[4])

#define	ZIO_PRIORITY_AGG		(zio_priority_table[5])

#define	ZIO_PRIORITY_FREE		(zio_priority_table[6])

#define	ZIO_PRIORITY_ASYNC_WRITE	(zio_priority_table[7])

#define	ZIO_PRIORITY_ASYNC_READ		(zio_priority_table[8])

#define	ZIO_PRIORITY_RESILVER		(zio_priority_table[9])

#define	ZIO_PRIORITY_SCRUB		(zio_priority_table[10])

#define	ZIO_PRIORITY_DDT_PREFETCH	(zio_priority_table[11])

#define	ZIO_PRIORITY_TABLE_SIZE		12

#define	ZIO_PIPELINE_CONTINUE		0x100

#define	ZIO_PIPELINE_STOP		0x101

enum zio_flag {

	/*

	 * Flags inherited by gang, ddt, and vdev children,

	 * and that must be equal for two zios to aggregate

	 */

	ZIO_FLAG_DONT_AGGREGATE	= 1 << 0,

	ZIO_FLAG_IO_REPAIR	= 1 << 1,

	ZIO_FLAG_SELF_HEAL	= 1 << 2,

	ZIO_FLAG_RESILVER	= 1 << 3,

	ZIO_FLAG_SCRUB		= 1 << 4,

	ZIO_FLAG_SCAN_THREAD	= 1 << 5,

#define	ZIO_FLAG_AGG_INHERIT	(ZIO_FLAG_CANFAIL - 1)

	/*

	 * Flags inherited by ddt, gang, and vdev children.

	 */

	ZIO_FLAG_CANFAIL	= 1 << 6,	/* must be first for INHERIT */

	ZIO_FLAG_SPECULATIVE	= 1 << 7,

	ZIO_FLAG_CONFIG_WRITER	= 1 << 8,

	ZIO_FLAG_DONT_RETRY	= 1 << 9,

	ZIO_FLAG_DONT_CACHE	= 1 << 10,

	ZIO_FLAG_NODATA		= 1 << 11,

	ZIO_FLAG_INDUCE_DAMAGE	= 1 << 12,

#define	ZIO_FLAG_DDT_INHERIT	(ZIO_FLAG_IO_RETRY - 1)

#define	ZIO_FLAG_GANG_INHERIT	(ZIO_FLAG_IO_RETRY - 1)

	/*

	 * Flags inherited by vdev children.

	 */

	ZIO_FLAG_IO_RETRY	= 1 << 13,	/* must be first for INHERIT */

	ZIO_FLAG_PROBE		= 1 << 14,

	ZIO_FLAG_TRYHARD	= 1 << 15,

	ZIO_FLAG_OPTIONAL	= 1 << 16,

#define	ZIO_FLAG_VDEV_INHERIT	(ZIO_FLAG_DONT_QUEUE - 1)

	/*

	 * Flags not inherited by any children.

	 */

	ZIO_FLAG_DONT_QUEUE	= 1 << 17,	/* must be first for INHERIT */

	ZIO_FLAG_DONT_PROPAGATE	= 1 << 18,

	ZIO_FLAG_IO_BYPASS	= 1 << 19,

	ZIO_FLAG_IO_REWRITE	= 1 << 20,

	ZIO_FLAG_RAW		= 1 << 21,

	ZIO_FLAG_GANG_CHILD	= 1 << 22,

	ZIO_FLAG_DDT_CHILD	= 1 << 23,

	ZIO_FLAG_GODFATHER	= 1 << 24

};

#define	ZIO_FLAG_MUSTSUCCEED		0

#define	ZIO_DDT_CHILD_FLAGS(zio)				\

	(((zio)->io_flags & ZIO_FLAG_DDT_INHERIT) |		\

	ZIO_FLAG_DDT_CHILD | ZIO_FLAG_CANFAIL)

#define	ZIO_GANG_CHILD_FLAGS(zio)				\

	(((zio)->io_flags & ZIO_FLAG_GANG_INHERIT) |		\

	ZIO_FLAG_GANG_CHILD | ZIO_FLAG_CANFAIL)

#define	ZIO_VDEV_CHILD_FLAGS(zio)				\

	(((zio)->io_flags & ZIO_FLAG_VDEV_INHERIT) |		\

	ZIO_FLAG_CANFAIL)

enum zio_child {

	ZIO_CHILD_VDEV = 0,

	ZIO_CHILD_GANG,

	ZIO_CHILD_DDT,

	ZIO_CHILD_LOGICAL,

	ZIO_CHILD_TYPES

};

enum zio_wait_type {

	ZIO_WAIT_READY = 0,

	ZIO_WAIT_DONE,

	ZIO_WAIT_TYPES

};

/*

 * We'll take the unused errnos, 'EBADE' and 'EBADR' (from the Convergent

 * graveyard) to indicate checksum errors and fragmentation.

 */

#define	ECKSUM	EBADE

#define	EFRAGS	EBADR

typedef void zio_done_func_t(zio_t *zio);

extern uint8_t zio_priority_table[ZIO_PRIORITY_TABLE_SIZE];

extern char *zio_type_name[ZIO_TYPES];

/*

 * A bookmark is a four-tuple <objset, object, level, blkid> that uniquely

 * identifies any block in the pool.  By convention, the meta-objset (MOS)

 * is objset 0, and the meta-dnode is object 0.  This covers all blocks

 * except root blocks and ZIL blocks, which are defined as follows:

 *

 * Root blocks (objset_phys_t) are object 0, level -1:  <objset, 0, -1, 0>.

 * ZIL blocks are bookmarked <objset, 0, -2, blkid == ZIL sequence number>.

 * dmu_sync()ed ZIL data blocks are bookmarked <objset, object, -2, blkid>.

 *

 * Note: this structure is called a bookmark because its original purpose

 * was to remember where to resume a pool-wide traverse.

 *

 * Note: this structure is passed between userland and the kernel.

 * Therefore it must not change size or alignment between 32/64 bit

 * compilation options.

 */

typedef struct zbookmark {

	uint64_t	zb_objset;

	uint64_t	zb_object;

	int64_t		zb_level;

	uint64_t	zb_blkid;

} zbookmark_t;

#define	SET_BOOKMARK(zb, objset, object, level, blkid)  \

{                                                       \

	(zb)->zb_objset = objset;                       \

	(zb)->zb_object = object;                       \

	(zb)->zb_level = level;                         \

	(zb)->zb_blkid = blkid;                         \

}

#define	ZB_DESTROYED_OBJSET	(-1ULL)

#define	ZB_ROOT_OBJECT		(0ULL)

#define	ZB_ROOT_LEVEL		(-1LL)

#define	ZB_ROOT_BLKID		(0ULL)

#define	ZB_ZIL_OBJECT		(0ULL)

#define	ZB_ZIL_LEVEL		(-2LL)

typedef struct zio_prop {

	enum zio_checksum	zp_checksum;

	enum zio_compress	zp_compress;

	dmu_object_type_t	zp_type;

	uint8_t			zp_level;

	uint8_t			zp_copies;

	uint8_t			zp_dedup;

	uint8_t			zp_dedup_verify;

} zio_prop_t;

typedef struct zio_cksum_report zio_cksum_report_t;

typedef void zio_cksum_finish_f(zio_cksum_report_t *rep,

    const void *good_data);

typedef void zio_cksum_free_f(void *cbdata, size_t size);

struct zio_bad_cksum;				/* defined in zio_checksum.h */

struct zio_cksum_report {

	struct zio_cksum_report *zcr_next;

	nvlist_t		*zcr_ereport;

	nvlist_t		*zcr_detector;

	void			*zcr_cbdata;

	size_t			zcr_cbinfo;	/* passed to zcr_free() */

	uint64_t		zcr_align;

	uint64_t		zcr_length;

	zio_cksum_finish_f	*zcr_finish;

	zio_cksum_free_f	*zcr_free;

	/* internal use only */

	struct zio_bad_cksum	*zcr_ckinfo;	/* information from failure */

};

typedef void zio_vsd_cksum_report_f(zio_t *zio, zio_cksum_report_t *zcr,

    void *arg);

zio_vsd_cksum_report_f	zio_vsd_default_cksum_report;

typedef struct zio_vsd_ops {

	zio_done_func_t		*vsd_free;

	zio_vsd_cksum_report_f	*vsd_cksum_report;

} zio_vsd_ops_t;

typedef struct zio_gang_node {

	zio_gbh_phys_t		*gn_gbh;

	struct zio_gang_node	*gn_child[SPA_GBH_NBLKPTRS];

} zio_gang_node_t;

typedef zio_t *zio_gang_issue_func_t(zio_t *zio, blkptr_t *bp,

    zio_gang_node_t *gn, void *data);

typedef void zio_transform_func_t(zio_t *zio, void *data, uint64_t size);

typedef struct zio_transform {

	void			*zt_orig_data;

	uint64_t		zt_orig_size;

	uint64_t		zt_bufsize;

	zio_transform_func_t	*zt_transform;

	struct zio_transform	*zt_next;

} zio_transform_t;

typedef int zio_pipe_stage_t(zio_t *zio);

/*

 * The io_reexecute flags are distinct from io_flags because the child must

 * be able to propagate them to the parent.  The normal io_flags are local

 * to the zio, not protected by any lock, and not modifiable by children;

 * the reexecute flags are protected by io_lock, modifiable by children,

 * and always propagated -- even when ZIO_FLAG_DONT_PROPAGATE is set.

 */

#define	ZIO_REEXECUTE_NOW	0x01

#define	ZIO_REEXECUTE_SUSPEND	0x02

typedef struct zio_link {

	zio_t		*zl_parent;

	zio_t		*zl_child;

	list_node_t	zl_parent_node;

	list_node_t	zl_child_node;

} zio_link_t;

struct zio {

	/* Core information about this I/O */

	zbookmark_t	io_bookmark;

	zio_prop_t	io_prop;

	zio_type_t	io_type;

	enum zio_child	io_child_type;

	int		io_cmd;

	uint8_t		io_priority;

	uint8_t		io_reexecute;

	uint8_t		io_state[ZIO_WAIT_TYPES];

	uint64_t	io_txg;

	spa_t		*io_spa;

	blkptr_t	*io_bp;

	blkptr_t	*io_bp_override;

	blkptr_t	io_bp_copy;

	list_t		io_parent_list;

	list_t		io_child_list;

	zio_link_t	*io_walk_link;

	zio_t		*io_logical;

	zio_transform_t *io_transform_stack;

	/* Callback info */

	zio_done_func_t	*io_ready;

	zio_done_func_t	*io_done;

	void		*io_private;

	int64_t		io_prev_space_delta;	/* DMU private */

	blkptr_t	io_bp_orig;

	/* Data represented by this I/O */

	void		*io_data;

	void		*io_orig_data;

	uint64_t	io_size;

	uint64_t	io_orig_size;

	/* Stuff for the vdev stack */

	vdev_t		*io_vd;

	void		*io_vsd;

	const zio_vsd_ops_t *io_vsd_ops;

	uint64_t	io_offset;

	uint64_t	io_deadline;

	avl_node_t	io_offset_node;

	avl_node_t	io_deadline_node;

	avl_tree_t	*io_vdev_tree;

	/* Internal pipeline state */

	enum zio_flag	io_flags;

	enum zio_stage	io_stage;

	enum zio_stage	io_pipeline;

	enum zio_flag	io_orig_flags;

	enum zio_stage	io_orig_stage;

	enum zio_stage	io_orig_pipeline;

	int		io_error;

	int		io_child_error[ZIO_CHILD_TYPES];

	uint64_t	io_children[ZIO_CHILD_TYPES][ZIO_WAIT_TYPES];

	uint64_t	io_child_count;

	uint64_t	io_parent_count;

	uint64_t	*io_stall;

	zio_t		*io_gang_leader;

	zio_gang_node_t	*io_gang_tree;

	void		*io_executor;

	void		*io_waiter;

	kmutex_t	io_lock;

	kcondvar_t	io_cv;

	/* FMA state */

	zio_cksum_report_t *io_cksum_report;

	uint64_t	io_ena;

	/* Taskq dispatching state */

	taskq_ent_t	io_tqent;

};

extern zio_t *zio_null(zio_t *pio, spa_t *spa, vdev_t *vd,

    zio_done_func_t *done, void *private, enum zio_flag flags);

extern zio_t *zio_root(spa_t *spa,

    zio_done_func_t *done, void *private, enum zio_flag flags);

extern zio_t *zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, void *data,

    uint64_t size, zio_done_func_t *done, void *private,

    int priority, enum zio_flag flags, const zbookmark_t *zb);

extern zio_t *zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,

    void *data, uint64_t size, const zio_prop_t *zp,

    zio_done_func_t *ready, zio_done_func_t *done, void *private,

    int priority, enum zio_flag flags, const zbookmark_t *zb);

extern zio_t *zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,

    void *data, uint64_t size, zio_done_func_t *done, void *private,

    int priority, enum zio_flag flags, zbookmark_t *zb);

extern void zio_write_override(zio_t *zio, blkptr_t *bp, int copies);

extern void zio_free(spa_t *spa, uint64_t txg, const blkptr_t *bp);

extern zio_t *zio_claim(zio_t *pio, spa_t *spa, uint64_t txg,

    const blkptr_t *bp,

    zio_done_func_t *done, void *private, enum zio_flag flags);

extern zio_t *zio_ioctl(zio_t *pio, spa_t *spa, vdev_t *vd, int cmd,

    zio_done_func_t *done, void *private, int priority, enum zio_flag flags);

extern zio_t *zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset,

    uint64_t size, void *data, int checksum,

    zio_done_func_t *done, void *private, int priority, enum zio_flag flags,

    boolean_t labels);

extern zio_t *zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset,

    uint64_t size, void *data, int checksum,

    zio_done_func_t *done, void *private, int priority, enum zio_flag flags,

    boolean_t labels);

extern zio_t *zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg,

    const blkptr_t *bp, enum zio_flag flags);

extern int zio_alloc_zil(spa_t *spa, uint64_t txg, blkptr_t *new_bp,

    blkptr_t *old_bp, uint64_t size, boolean_t use_slog);

extern void zio_free_zil(spa_t *spa, uint64_t txg, blkptr_t *bp);

extern void zio_flush(zio_t *zio, vdev_t *vd);

extern void zio_shrink(zio_t *zio, uint64_t size);

extern int zio_wait(zio_t *zio);

extern void zio_nowait(zio_t *zio);

extern void zio_execute(zio_t *zio);

extern void zio_interrupt(zio_t *zio);

extern zio_t *zio_walk_parents(zio_t *cio);

extern zio_t *zio_walk_children(zio_t *pio);

extern zio_t *zio_unique_parent(zio_t *cio);

extern void zio_add_child(zio_t *pio, zio_t *cio);