sys/lvm/md_sp.h

	md_sp.h revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (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 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#ifndef _SYS__MD_SP_H
#define _SYS__MD_SP_H

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

#include <sys/lvm/mdvar.h>

#ifdef  __cplusplus
extern "C" {
#endif

#define META_SP_DEBUG ("META_SP_DEBUG")

/* on-disk structures */
#define MD_SP_MAGIC         (0x20000127)
/* number of sectors to reserve at the beginning of the volume */
#define MD_SP_START         (0)
/* current watermark version number */
#define MD_SP_VERSION           (1)
/* size of a watermark in sectors */
#define MD_SP_WMSIZE            (1)
/* free watermark name */
#define MD_SP_FREEWMNAME        "free"
/* local set name */
#define MD_SP_LOCALSETNAME      ""
/* maximum length of a soft partition metadevice name. eg. dXXXX\0 */
#define MD_SP_MAX_DEVNAME_PLUS_1    (6)

/*
 * The size of this structure is forced to be 512 bytes (ie a sector) by
 * using a union. Note the MD_MAX_SETNAME_PLUS_1 is set in meta_basic.h
 */

#if _LONG_LONG_ALIGNMENT == 8 && _LONG_LONG_ALIGNMENT_32 == 4
#pragma pack(4)
#endif
typedef union mp_watermark {
    struct {
        uint32_t    wm_magic;   /* magic number */
        uint32_t    wm_version; /* version number */
        uint32_t    wm_checksum;    /* structure checksum */
        uint32_t    wm_seq;     /* sequence number */
        uint32_t    wm_type;    /* extent type */
        uint64_t    wm_length;  /* length of extent */
        char        wm_mdname[MD_MAX_SETNAME_PLUS_1 +
                    MD_SP_MAX_DEVNAME_PLUS_1];  /* SP name */
        char        wm_setname[MD_MAX_SETNAME_PLUS_1]; /* setname */
    } wm;
    uchar_t         wm_pad[MD_SP_WMSIZE * DEV_BSIZE];
} mp_watermark_t;
#if _LONG_LONG_ALIGNMENT == 8 && _LONG_LONG_ALIGNMENT_32 == 4
#pragma pack()
#endif

#define wm_magic    wm.wm_magic
#define wm_version  wm.wm_version
#define wm_checksum wm.wm_checksum
#define wm_seq      wm.wm_seq
#define wm_type     wm.wm_type
#define wm_length   wm.wm_length
#define wm_mdname   wm.wm_mdname
#define wm_setname  wm.wm_setname

/* Watermark types */
typedef enum sp_ext_type {
    EXTTYP_ALLOC    = 0x1,  /* this extent is in use by a soft partition */
    EXTTYP_FREE = 0x2,  /* extent is not in use */
    EXTTYP_END  = 0x3,  /* last descriptor on the volume */
    EXTTYP_RESERVED = 0x4   /* extent will not be used or updated */
} sp_ext_type_t;

/* ioctls */
#define MD_IOC_SPSTATUS     (MDIOC_MISC|0)
#define MD_IOC_SPUPDATEWM   (MDIOC_MISC|1)
#define MD_IOC_SPREADWM     (MDIOC_MISC|2)

#ifdef _KERNEL

/*
 * parent and child save areas provide the mechanism for tracking
 * I/O operations in the metadevice stack.
 */

/* soft partitioning parent save area */
typedef struct md_spps {        /* soft partition parent save */
    DAEMON_QUEUE
    mp_unit_t   *ps_un;     /* sp unit structure */
    mdi_unit_t  *ps_ui;     /* incore unit struct */
    buf_t       *ps_bp;     /* parent buffer */
    caddr_t      ps_addr;
    int      ps_frags;
    int      ps_flags;
    /*
     * New structure members should be added here; fields added
     * after ps_mx will not be zeroed during initialization.
     */
    kmutex_t     ps_mx;
} md_spps_t;

/* parent save flags. */
#define MD_SPPS_ERROR       0x0001
#define MD_SPPS_DONTFREE    0x0002
#define MD_SPPS_DONE        0x0004

/* soft partitioning child save area */
typedef struct md_spcs {
    DAEMON_QUEUE
    minor_t      cs_mdunit; /* child minor number */
    md_spps_t   *cs_ps;     /* parent save pointer */
    /* Add new structure members HERE!! */
    buf_t        cs_buf;    /* child buffer */
    /*  DO NOT add struture members here; cs_buf is dynamically sized */
} md_spcs_t;

#define SPPS_FREE(kc, ps)           \
{                       \
    if ((ps)->ps_flags & MD_SPPS_DONTFREE)  \
        (ps)->ps_flags |= MD_SPPS_DONE; \
    else                    \
        kmem_cache_free((kc), (ps));    \
}

/* externals from sp.c */
extern int  sp_build_incore(void *, int);
extern void reset_sp(mp_unit_t *, minor_t, int);
extern int  sp_directed_read(minor_t, vol_directed_rd_t *, int);

/* externals from sp_ioctl.c */
extern int  md_sp_ioctl(dev_t dev, int cmd, void *data,
    int mode, IOLOCK *lockp);

#endif  /* _KERNEL */

#ifdef  __cplusplus
}
#endif

#endif  /* _SYS__MD_SP_H */