usr/src/uts/common/sys/fssnap_if.h

root/usr/src/uts/common/sys/fssnap_if.h
/*
 * 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_FSSNAP_IF_H
#define _SYS_FSSNAP_IF_H

#include <sys/types.h>
#include <sys/fssnap.h>

#ifdef  __cplusplus
extern "C" {
#endif

/*
 * ioctl's for communicating between the user and the fssnapctl device.
 * Also used to communicate between fssnapctl and the file system.
 * Pack fiosnapcreate for amd64 to make struct size same as x86.
 */

#if _LONG_LONG_ALIGNMENT == 8 && _LONG_LONG_ALIGNMENT_32 == 4
#pragma pack(4)
#endif

struct fiosnapcreate {
        int     rootfiledesc;   /* IN  fd for root of fs to be snapshotted */
        int     backfiledesc;   /* IN  backing store file for snapshot data */
        uint_t  snapshotnumber; /* OUT snapshot number created */
        uint_t  chunksize;      /* IN  chunk size, 0 == fs defined */
        u_offset_t      maxsize; /* IN  maximum size of backing file */
        char    backfilename[MAXPATHLEN];       /* IN  for bookkeeping */
        int     error;          /* OUT error code */
};

struct fiosnapcreate_multi {
        int     rootfiledesc;   /* IN  fd for root of fs to be snapshotted */
        uint_t  snapshotnumber; /* OUT snapshot number created */
        uint_t  chunksize;      /* IN  chunk size, 0 == fs defined */
        u_offset_t      maxsize; /* IN  max size of entire backing store */
        char    backfilename[MAXPATHLEN];       /* IN  for bookkeeping */
        int     error;          /* OUT error code */
        int     backfilecount;  /* IN  number of backing store files */
        u_offset_t      backfilesize; /* IN maximum size of each backfile */
        int     backfiledesc[1]; /* IN  backing store files for snapshot data */
};

#if _LONG_LONG_ALIGNMENT == 8 && _LONG_LONG_ALIGNMENT_32 == 4
#pragma pack()
#endif

struct fiosnapdelete {
        int     rootfiledesc;   /* IN  fd for root of fs to be unsnapshotted */
        uint_t  snapshotnumber; /* OUT snapshot number deleted */
        int     error;          /* OUT error code */
};

/* ioctl error returns */
#define FIOCOW_EREADONLY (1)    /* read only file system */
#define FIOCOW_EBUSY    (2)     /* snapshot already enabled */
#define FIOCOW_EULOCK   (3)     /* file system is locked */
#define FIOCOW_EWLOCK   (4)     /* file system could not be write locked */
#define FIOCOW_EFLUSH   (5)     /* file system could not be flushed */
#define FIOCOW_ECLEAN   (6)     /* file system may not be stable */
#define FIOCOW_ENOULOCK (7)     /* file system could not be unlocked */
#define FIOCOW_ECHUNKSZ (8)     /* chunksize is less than fs fragment size */
#define FIOCOW_ECREATE  (9)     /* could not allocate/create snapshot */
#define FIOCOW_EBITMAP  (10)    /* error scanning file system bitmaps */
#define FIOCOW_EBACKFILE (11)   /* bad backing file path passed in */

/*
 * make the control device minor number high so minor numbers match
 * snapshot numbers.
 */
#define SNAP_CTL_MINOR  (L_MAXMIN32)
#define SNAP_NAME       "fssnap"
#define SNAP_CTL_NODE   "ctl"
#define SNAP_CTL_NAME   SNAP_NAME SNAP_CTL_NODE
#define SNAP_BLOCK_NAME SNAP_NAME
#define SNAP_CHAR_NAME  "r" SNAP_NAME

/* kstat names */
#define FSSNAP_KSTAT_HIGHWATER          "highwater"
#define FSSNAP_KSTAT_MNTPT              "mountpoint"
#define FSSNAP_KSTAT_BFNAME             "bfname"
#define FSSNAP_KSTAT_NUM                "numericstats"

/* numericstats kstat names */
#define FSSNAP_KSTAT_NUM_STATE          "state"
#define FSSNAP_KSTAT_NUM_BFSIZE         "bfsize"
#define FSSNAP_KSTAT_NUM_MAXSIZE        "maxsize"
#define FSSNAP_KSTAT_NUM_CHUNKSIZE      "chunksize"
#define FSSNAP_KSTAT_NUM_CREATETIME     "createtime"

#if defined(_KERNEL)
/*
 * snapshot operations implemented by the loadable snapshot subsystem
 */
struct fssnap_operations {
        void *(*fssnap_create)(chunknumber_t, uint_t, u_offset_t,
            struct vnode *, int, struct vnode **, char *, u_offset_t);
        void (*fssnap_set_candidate)(void *, chunknumber_t);
        int (*fssnap_is_candidate)(void *, u_offset_t);
        int  (*fssnap_create_done)(void *);
        int (*fssnap_delete)(void *);
        void (*fssnap_strategy)(void *, struct buf *);
};


/* global variables to manage interface operations */
extern struct fssnap_operations snapops;

/* External functions called by file systems that use snapshots */
extern int fssnap_init(void);
extern int fssnap_fini(void);
extern void *fssnap_create(chunknumber_t, uint_t, u_offset_t, struct vnode *,
    int, struct vnode **, char *, u_offset_t);
extern void fssnap_set_candidate(void *, chunknumber_t);
extern int fssnap_is_candidate(void *, u_offset_t);
extern int  fssnap_create_done(void *);
extern int fssnap_delete(void *);
extern void fssnap_strategy(void *, struct buf *);

#endif /* _KERNEL */

#ifdef  __cplusplus
}
#endif

#endif /* _SYS_FSSNAP_IF_H */
Illumos
