/*

 * 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 2006 Sun Microsystems, Inc.  All rights reserved.

 * Use is subject to license terms.

 */

#ifndef _ZIO_H

#define	_ZIO_H

#pragma ident	"%Z%%M%	%I%	%E% SMI"

#include <sys/zfs_context.h>

#include <sys/spa.h>

#include <sys/txg.h>

#include <sys/avl.h>

#include <sys/dkio.h>

#include <sys/fs/zfs.h>

#include <sys/zio_impl.h>

#ifdef	__cplusplus

extern "C" {

#endif

#define	ZBT_MAGIC	0x210da7ab10c7a11ULL	/* zio data bloc tail */

typedef struct zio_block_tail {

	uint64_t	zbt_magic;	/* for validation, endianness	*/

	zio_cksum_t	zbt_cksum;	/* 256-bit checksum		*/

} zio_block_tail_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_block_tail_t)) / sizeof (blkptr_t))

#define	SPA_GBH_FILLER		((SPA_GANGBLOCKSIZE - \

	sizeof (zio_block_tail_t) - \

	(SPA_GBH_NBLKPTRS * sizeof (blkptr_t))) /\

	sizeof (uint64_t))

#define	ZIO_GET_IOSIZE(zio)	\

	(BP_IS_GANG((zio)->io_bp) ? \

	SPA_GANGBLOCKSIZE : BP_GET_PSIZE((zio)->io_bp))

typedef struct zio_gbh {

	blkptr_t		zg_blkptr[SPA_GBH_NBLKPTRS];

	uint64_t		zg_filler[SPA_GBH_FILLER];

	zio_block_tail_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_FUNCTIONS

};

#define	ZIO_CHECKSUM_ON_VALUE	ZIO_CHECKSUM_FLETCHER_2

#define	ZIO_CHECKSUM_DEFAULT	ZIO_CHECKSUM_ON

enum zio_compress {

	ZIO_COMPRESS_INHERIT = 0,

	ZIO_COMPRESS_ON,

	ZIO_COMPRESS_OFF,

	ZIO_COMPRESS_LZJB,

	ZIO_COMPRESS_FUNCTIONS

};

#define	ZIO_COMPRESS_ON_VALUE	ZIO_COMPRESS_LZJB

#define	ZIO_COMPRESS_DEFAULT	ZIO_COMPRESS_OFF

#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_ASYNC_READ		(zio_priority_table[3])

#define	ZIO_PRIORITY_ASYNC_WRITE	(zio_priority_table[4])

#define	ZIO_PRIORITY_FREE		(zio_priority_table[5])

#define	ZIO_PRIORITY_CACHE_FILL		(zio_priority_table[6])

#define	ZIO_PRIORITY_LOG_WRITE		(zio_priority_table[7])

#define	ZIO_PRIORITY_RESILVER		(zio_priority_table[8])

#define	ZIO_PRIORITY_SCRUB		(zio_priority_table[9])

#define	ZIO_PRIORITY_TABLE_SIZE		10

#define	ZIO_FLAG_MUSTSUCCEED		0x00000

#define	ZIO_FLAG_CANFAIL		0x00001

#define	ZIO_FLAG_FAILFAST		0x00002

#define	ZIO_FLAG_CONFIG_HELD		0x00004

#define	ZIO_FLAG_DONT_CACHE		0x00010

#define	ZIO_FLAG_DONT_QUEUE		0x00020

#define	ZIO_FLAG_DONT_PROPAGATE		0x00040

#define	ZIO_FLAG_DONT_RETRY		0x00080

#define	ZIO_FLAG_PHYSICAL		0x00100

#define	ZIO_FLAG_IO_BYPASS		0x00200

#define	ZIO_FLAG_IO_REPAIR		0x00400

#define	ZIO_FLAG_SPECULATIVE		0x00800

#define	ZIO_FLAG_RESILVER		0x01000

#define	ZIO_FLAG_SCRUB			0x02000

#define	ZIO_FLAG_SCRUB_THREAD		0x04000

#define	ZIO_FLAG_SUBBLOCK		0x08000

#define	ZIO_FLAG_NOBOOKMARK		0x10000

#define	ZIO_FLAG_GANG_INHERIT		\

	(ZIO_FLAG_CANFAIL |		\

	ZIO_FLAG_FAILFAST |		\

	ZIO_FLAG_CONFIG_HELD |		\

	ZIO_FLAG_DONT_RETRY |		\

	ZIO_FLAG_IO_REPAIR |		\

	ZIO_FLAG_SPECULATIVE |		\

	ZIO_FLAG_RESILVER |		\

	ZIO_FLAG_SCRUB |		\

	ZIO_FLAG_SCRUB_THREAD)

#define	ZIO_FLAG_VDEV_INHERIT		\

	(ZIO_FLAG_GANG_INHERIT |	\

	ZIO_FLAG_DONT_CACHE |		\

	ZIO_FLAG_PHYSICAL)

/*

 * We'll take the unused errno 'EBADE' (from the Convergent graveyard)

 * to indicate checksum errors.

 */

#define	ECKSUM	EBADE

typedef struct zio zio_t;

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, the meta-dnode is object 0, the root block (osphys_t) is

 * level -1 of the meta-dnode, and intent log blocks (which are chained

 * off the root block) have blkid == sequence number.  In summary:

 *

 *	mos is objset 0

 *	meta-dnode is object 0

 *	root block is <objset, 0, -1, 0>

 *	intent log is <objset, 0, -1, ZIL sequence number>

 *

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

 * to remember where to resume a pool-wide traverse.  The absolute ordering

 * for block visitation during traversal is defined in compare_bookmark().

 *

 * 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;

struct zio {

	/* Core information about this I/O */

	zio_t		*io_parent;

	zio_t		*io_root;

	spa_t		*io_spa;

	zbookmark_t	io_bookmark;

	enum zio_checksum io_checksum;

	enum zio_compress io_compress;

	int		io_ndvas;

	uint64_t	io_txg;

	blkptr_t	*io_bp;

	blkptr_t	io_bp_copy;

	zio_t		*io_child;

	zio_t		*io_sibling_prev;

	zio_t		*io_sibling_next;

	zio_transform_t *io_transform_stack;

	zio_t		*io_logical;

	/* Callback info */

	zio_done_func_t	*io_done;

	void		*io_private;

	blkptr_t	io_bp_orig;

	/* Data represented by this I/O */

	void		*io_data;

	uint64_t	io_size;

	/* Stuff for the vdev stack */

	vdev_t		*io_vd;

	void		*io_vsd;

	uint64_t	io_offset;

	uint64_t	io_deadline;

	uint64_t	io_timestamp;

	avl_node_t	io_offset_node;

	avl_node_t	io_deadline_node;

	avl_tree_t	*io_vdev_tree;

	zio_t		*io_delegate_list;

	zio_t		*io_delegate_next;

	/* Internal pipeline state */

	int		io_flags;

	enum zio_type	io_type;

	enum zio_stage	io_stage;

	uint8_t		io_stalled;

	uint8_t		io_priority;

	struct dk_callback io_dk_callback;

	int		io_cmd;

	int		io_retries;

	int		io_error;

	uint32_t	io_numerrors;

	uint32_t	io_pipeline;

	uint32_t	io_async_stages;

	uint64_t	io_children_notready;

	uint64_t	io_children_notdone;

	void		*io_waiter;

	kmutex_t	io_lock;

	kcondvar_t	io_cv;

	/* FMA state */

	uint64_t	io_ena;

};

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

    zio_done_func_t *done, void *private, int flags);

extern zio_t *zio_root(spa_t *spa,

    zio_done_func_t *done, void *private, int flags);

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

    uint64_t size, zio_done_func_t *done, void *private,

    int priority, int flags, zbookmark_t *zb);

extern zio_t *zio_write(zio_t *pio, spa_t *spa, int checksum, int compress,

    int ncopies, uint64_t txg, blkptr_t *bp, void *data, uint64_t size,

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

    zbookmark_t *zb);

extern zio_t *zio_rewrite(zio_t *pio, spa_t *spa, int checksum,

    uint64_t txg, blkptr_t *bp, void *data, uint64_t size,

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

    zbookmark_t *zb);

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

    zio_done_func_t *done, void *private);

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

    zio_done_func_t *done, void *private);

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, int 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, int flags);

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, int flags);

extern int zio_alloc_blk(spa_t *spa, uint64_t size, blkptr_t *bp, uint64_t txg);

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

extern int zio_wait(zio_t *zio);

extern void zio_nowait(zio_t *zio);

extern void *zio_buf_alloc(size_t size);

extern void zio_buf_free(void *buf, size_t size);

/*

 * Move an I/O to the next stage of the pipeline and execute that stage.

 * There's no locking on io_stage because there's no legitimate way for

 * multiple threads to be attempting to process the same I/O.

 */

extern void zio_next_stage(zio_t *zio);

extern void zio_next_stage_async(zio_t *zio);

extern void zio_wait_children_done(zio_t *zio);

/*

 * Delegate I/O to a child vdev.

 */

extern zio_t *zio_vdev_child_io(zio_t *zio, blkptr_t *bp, vdev_t *vd,

    uint64_t offset, void *data, uint64_t size, int type, int priority,

    int flags, zio_done_func_t *done, void *private);

extern void zio_vdev_io_bypass(zio_t *zio);

extern void zio_vdev_io_reissue(zio_t *zio);

extern void zio_vdev_io_redone(zio_t *zio);

extern void zio_checksum_verified(zio_t *zio);

extern void zio_set_gang_verifier(zio_t *zio, zio_cksum_t *zcp);

extern uint8_t zio_checksum_select(uint8_t child, uint8_t parent);

extern uint8_t zio_compress_select(uint8_t child, uint8_t parent);

boolean_t zio_should_retry(zio_t *zio);

/*

 * Initial setup and teardown.

 */

extern void zio_init(void);

extern void zio_fini(void);

/*

 * Fault injection

 */

struct zinject_record;

extern uint32_t zio_injection_enabled;

extern int zio_inject_fault(char *name, int flags, int *id,

    struct zinject_record *record);

extern int zio_inject_list_next(int *id, char *name, size_t buflen,

    struct zinject_record *record);

extern int zio_clear_fault(int id);

extern int zio_handle_fault_injection(zio_t *zio, int error);

extern int zio_handle_device_injection(vdev_t *vd, int error);

#ifdef	__cplusplus

}

#endif

#endif	/* _ZIO_H */