/*-
 * Copyright (c) 1990 Jan-Simon Pendry
 * Copyright (c) 1990 Imperial College of Science, Technology & Medicine
 * Copyright (c) 1990, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Jan-Simon Pendry at Imperial College, London.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include "am.h"

extern qelem mfhead;
qelem mfhead = { &mfhead, &mfhead };

int mntfs_allocated;

#ifdef notdef
/*
 * This is the default attributes field which
 * is copied into every new node to be created.
 * The individual filesystem fs_init() routines
 * patch the copy to represent the particular
 * details for the relevant filesystem type
 */
static struct fattr gen_fattr = {
        NFDIR,                          /* type */
        NFSMODE_DIR | 0555,             /* mode */
        2,                              /* nlink */
        0,                              /* uid */
        0,                              /* gid */
        512,                            /* size */
        4096,                           /* blocksize */
        0,                              /* rdev */
        1,                              /* blocks */
        0,                              /* fsid */
        0,                              /* fileid */
        { 0, 0 },                       /* atime */
        { 0, 0 },                       /* mtime */
        { 0, 0 },                       /* ctime */
};
#endif /* notdef */

mntfs *
dup_mntfs(mntfs *mf)
{
        if (mf->mf_refc == 0) {
                if (mf->mf_cid)
                        untimeout(mf->mf_cid);
                mf->mf_cid = 0;
#ifdef notdef
                mf->mf_error = -1;
                mf->mf_flags &= ~MFF_ERROR;
#endif
        }
        mf->mf_refc++;
        return mf;
}

static void
init_mntfs(mntfs *mf, am_ops *ops, am_opts *mo, char *mp, char *info,
    char *auto_opts, char *mopts, char *remopts)
{
        mf->mf_ops = ops;
        mf->mf_fo = mo;
        mf->mf_mount = strdup(mp);
        mf->mf_info = strdup(info);
        mf->mf_auto = strdup(auto_opts);
        mf->mf_mopts = strdup(mopts);
        mf->mf_remopts = strdup(remopts);
        mf->mf_refc = 1;
        mf->mf_flags = 0;
        mf->mf_error = -1;
        mf->mf_cid = 0;
        mf->mf_private = 0;
        mf->mf_prfree = 0;
#ifdef notdef
        mf->mf_attr.status = NFS_OK;
        mf->mf_fattr = gen_fattr;
        mf->mf_fattr.fsid = 42;
        mf->mf_fattr.fileid = 0;
        mf->mf_fattr.atime.seconds = clocktime();
        mf->mf_fattr.atime.useconds = 0;
        mf->mf_fattr.mtime = mf->mf_fattr.ctime = mf->mf_fattr.atime;
#endif

        if (ops->ffserver)
                mf->mf_server = (*ops->ffserver)(mf);
        else
                mf->mf_server = 0;
}

static mntfs *
alloc_mntfs(am_ops *ops, am_opts *mo, char *mp, char *info,
    char *auto_opts, char *mopts, char *remopts)
{
        mntfs *mf = ALLOC(mntfs);
        init_mntfs(mf, ops, mo, mp, info, auto_opts, mopts, remopts);
        ins_que(&mf->mf_q, &mfhead);
        mntfs_allocated++;

        return mf;
}

mntfs *
find_mntfs(am_ops *ops, am_opts *mo, char *mp, char *info,
    char *auto_opts, char *mopts, char *remopts)
{
        mntfs *mf;

#ifdef DEBUG
        dlog("Locating mntfs reference to %s", mp);
#endif /* DEBUG */
        ITER(mf, mntfs, &mfhead) {
                if (STREQ(mf->mf_mount, mp)) {
                        /*
                         * Handle cases where error ops are involved
                         */
                        if (ops == &efs_ops) {
                                /*
                                 * If the existing ops are not efs_ops
                                 * then continue...
                                 */
                                if (mf->mf_ops != &efs_ops)
                                        continue;
                        } else /* ops != &efs_ops */ {
                                /*
                                 * If the existing ops are efs_ops
                                 * then continue...
                                 */
                                if (mf->mf_ops == &efs_ops)
                                        continue;
                        }

                        if ((mf->mf_flags & MFF_RESTART) && amd_state == Run) {
                                /*
                                 * Restart a previously mounted filesystem.
                                 */
                                mntfs *mf2 = alloc_mntfs(&ifs_ops, mo, mp, info, auto_opts, mopts, remopts);
#ifdef DEBUG
                                dlog("Restarting filesystem %s", mf->mf_mount);
#endif /* DEBUG */
                                /*
                                 * Remember who we are restarting
                                 */
                                mf2->mf_private = dup_mntfs(mf);
                                mf2->mf_prfree = free_mntfs;
                                return mf2;
                        }
                        mf->mf_fo = mo;
                        if (!(mf->mf_flags & (MFF_MOUNTED|MFF_MOUNTING|MFF_UNMOUNTING))) {
                                fserver *fs;
                                mf->mf_flags &= ~MFF_ERROR;
                                mf->mf_error = -1;
                                mf->mf_auto = strealloc(mf->mf_auto, auto_opts);
                                mf->mf_mopts = strealloc(mf->mf_mopts, mopts);
                                mf->mf_remopts = strealloc(mf->mf_remopts, remopts);
                                mf->mf_info = strealloc(mf->mf_info, info);
                                if (mf->mf_private && mf->mf_prfree) {
                                        (*mf->mf_prfree)(mf->mf_private);
                                        mf->mf_private = 0;
                                }
                                fs = ops->ffserver ? (*ops->ffserver)(mf) : (fserver *) 0;
                                if (mf->mf_server)
                                        free_srvr(mf->mf_server);
                                mf->mf_server = fs;
                        }
                        return dup_mntfs(mf);
                }
        }

        return alloc_mntfs(ops, mo, mp, info, auto_opts, mopts, remopts);
}

mntfs *
new_mntfs()
{
        return alloc_mntfs(&efs_ops, (am_opts *) 0, "//nil//", ".", "", "", "");
}

static void
uninit_mntfs(mntfs *mf, int rmd)
{
        free(mf->mf_auto);
        free(mf->mf_mopts);
        free(mf->mf_remopts);
        free(mf->mf_info);
        if (mf->mf_private && mf->mf_prfree)
                (*mf->mf_prfree)(mf->mf_private);
        /*
         * Clean up any directories that were made
         */
        if (rmd && (mf->mf_flags & MFF_MKMNT))
                rmdirs(mf->mf_mount);
        free(mf->mf_mount);

        /*
         * Clean up the file server
         */
        if (mf->mf_server)
                free_srvr(mf->mf_server);

        /*
         * Don't do a callback on this mount
         */
        if (mf->mf_cid) {
                untimeout(mf->mf_cid);
                mf->mf_cid = 0;
        }
}

static void
discard_mntfs(void *arg)
{
        mntfs *mf = arg;

        rem_que(&mf->mf_q);
        /*
         * Free memory
         */
        uninit_mntfs(mf, TRUE);
        free(mf);

        --mntfs_allocated;
}

void
flush_mntfs(void)
{
        mntfs *mf;

        mf = FIRST(mntfs, &mfhead);
        while (mf != HEAD(mntfs, &mfhead)) {
                mntfs *mf2 = mf;
                mf = NEXT(mntfs, mf);
                if (mf2->mf_refc == 0 && mf2->mf_cid)
                        discard_mntfs(mf2);
        }
}

void
free_mntfs(void *arg)
{
        mntfs *mf = arg;

        if (--mf->mf_refc == 0) {
                if (mf->mf_flags & MFF_MOUNTED) {
                        int quoted;
                        mf->mf_flags &= ~MFF_MOUNTED;

                        /*
                         * Record for posterity
                         */
                        quoted = strchr(mf->mf_info, ' ') != 0; /* cheap */
                        plog(XLOG_INFO, "%s%s%s %sed fstype %s from %s",
                                quoted ? "\"" : "",
                                mf->mf_info,
                                quoted ? "\"" : "",
                                mf->mf_error ? "discard" : "unmount",
                                mf->mf_ops->fs_type, mf->mf_mount);
                }

                if (mf->mf_ops->fs_flags & FS_DISCARD) {
#ifdef DEBUG
                        dlog("Immediately discarding mntfs for %s", mf->mf_mount);
#endif /* DEBUG */
                        discard_mntfs(mf);
                } else {
#ifdef DEBUG
                        if (mf->mf_flags & MFF_RESTART) {
                                dlog("Discarding remount hook for %s", mf->mf_mount);
                        } else {
                                dlog("Discarding last mntfs reference to %s fstype %s",
                                        mf->mf_mount, mf->mf_ops->fs_type);
                        }
                        if (mf->mf_flags & (MFF_MOUNTED|MFF_MOUNTING|MFF_UNMOUNTING))
                                dlog("mntfs reference for %s still active", mf->mf_mount);
#endif /* DEBUG */
                        mf->mf_cid = timeout(ALLOWED_MOUNT_TIME,
                            discard_mntfs, mf);
                }
        }
}

mntfs *
realloc_mntfs(mntfs *mf, am_ops *ops, am_opts *mo, char *mp,
    char *info, char *auto_opts, char *mopts, char *remopts)
{
        mntfs *mf2;

        if (mf->mf_refc == 1 && mf->mf_ops == &ifs_ops && STREQ(mf->mf_mount, mp)) {
                /*
                 * If we are inheriting then just return
                 * the same node...
                 */
                return mf;
        }

        /*
         * Re-use the existing mntfs if it is mounted.
         * This traps a race in nfsx.
         */
        if (mf->mf_ops != &efs_ops &&
                        (mf->mf_flags & MFF_MOUNTED) &&
                        !FSRV_ISDOWN(mf->mf_server)) {
                mf->mf_fo = mo;
                return mf;
        }

        mf2 = find_mntfs(ops, mo, mp, info, auto_opts, mopts, remopts);
        free_mntfs(mf);
        return mf2;
}