fs/objfs/objfs_root.c

/*
 * 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 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

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


#include <fs/fs_subr.h>

#include <sys/errno.h>
#include <sys/kmem.h>
#include <sys/modctl.h>
#include <sys/objfs.h>
#include <sys/objfs_impl.h>
#include <sys/vfs_opreg.h>
#include <sys/systm.h>

extern int last_module_id;

static int objfs_root_do_lookup(vnode_t *, const char *, vnode_t **, ino64_t *,
    cred_t *, int, int *, pathname_t *);
static int objfs_root_do_readdir(vnode_t *, void *, int *,
    offset_t *, offset_t *, void *, int);

vnode_t *
objfs_create_root(vfs_t *vfsp)
{
    vnode_t *vp = gfs_root_create(sizeof (objfs_rootnode_t), vfsp,
        objfs_ops_root, OBJFS_INO_ROOT, NULL, NULL, OBJFS_NAME_MAX,
        objfs_root_do_readdir, objfs_root_do_lookup);

    return (vp);
}

/* ARGSUSED */
static int
objfs_root_getattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr,
    caller_context_t *ct)
{
    vap->va_type = VDIR;
    vap->va_mode = 0555;
    vap->va_nodeid = gfs_file_inode(vp);
    vap->va_nlink = objfs_nobjs() + 2;
    vap->va_size = vap->va_nlink;
    vap->va_atime.tv_sec = vp->v_vfsp->vfs_mtime;
    vap->va_atime.tv_nsec = 0;
    vap->va_mtime = vap->va_ctime = vap->va_atime;
    return (objfs_common_getattr(vp, vap));
}

/* ARGSUSED */
static int
objfs_root_do_lookup(vnode_t *vp, const char *nm, vnode_t **vpp, ino64_t *inop,
    cred_t *cr, int flags, int *deflags, pathname_t *rpnp)
{
    int result = ENOENT;
    struct modctl *mp;

    /*
     * Run through all the loaded modules on the system looking for
     * a matching module name.
     */
    mutex_enter(&mod_lock);
    mp = &modules;
    do {
        if (mp->mod_loaded &&
            strcmp(nm, mp->mod_modname) == 0) {
            /*
             * We drop mod_lock in order to do allocations,
             * as modctls are persistent.
             */
            mutex_exit(&mod_lock);
            *vpp = objfs_create_odirnode(vp, mp);
            *inop = OBJFS_INO_ODIR(mp->mod_id);
            mutex_enter(&mod_lock);
            result = 0;
            break;
        }
    } while ((mp = mp->mod_next) != &modules);
    mutex_exit(&mod_lock);

    return (result);
}

/* ARGSUSED */
int
objfs_root_do_readdir(vnode_t *vp, void *dp, int *eofp,
    offset_t *offp, offset_t *nextp, void *data, int flags)
{
    struct modctl **mpp = data;
    struct modctl *mp = *mpp;
    struct dirent64 *odp = dp;

    ASSERT(!(flags & V_RDDIR_ENTFLAGS));

    mutex_enter(&mod_lock);

    /* Check for EOF */
    if (*offp >= last_module_id) {
        *eofp = 1;
        mutex_exit(&mod_lock);
        return (0);
    }

    /*
     * Find the appropriate modctl
     */
    while (mp->mod_id < *offp) {
        mp = mp->mod_next;
        ASSERT(mp != &modules);
    }

    while (!mp->mod_loaded && mp != &modules)
        mp = mp->mod_next;

    if (mp == &modules && *offp != 0) {
        *eofp = 1;
        mutex_exit(&mod_lock);
        return (0);
    }

    /*
     * The modctl will not change, as they are persistent.
     */
    mutex_exit(&mod_lock);

    (void) strncpy(odp->d_name, mp->mod_modname, OBJFS_NAME_MAX);
    odp->d_ino = OBJFS_INO_ODIR(mp->mod_id);
    *offp = mp->mod_id;
    *nextp = mp->mod_id + 1;

    return (0);
}

/* ARGSUSED */
static int
objfs_root_readdir(vnode_t *vp, uio_t *uiop, cred_t *cr, int *eofp,
    caller_context_t *ct, int flags)
{
    struct modctl *mp = &modules;

    return (gfs_dir_readdir(vp, uiop, eofp, &mp, cr, ct, flags));
}

const fs_operation_def_t objfs_tops_root[] = {
    { VOPNAME_OPEN,     { .vop_open = objfs_dir_open } },
    { VOPNAME_CLOSE,    { .vop_close = objfs_common_close } },
    { VOPNAME_IOCTL,    { .error = fs_inval } },
    { VOPNAME_GETATTR,  { .vop_getattr = objfs_root_getattr } },
    { VOPNAME_ACCESS,   { .vop_access = objfs_dir_access } },
    { VOPNAME_READDIR,  { .vop_readdir = objfs_root_readdir } },
    { VOPNAME_LOOKUP,   { .vop_lookup = gfs_vop_lookup } },
    { VOPNAME_SEEK,     { .vop_seek = fs_seek } },
    { VOPNAME_INACTIVE, { .vop_inactive = gfs_vop_inactive } },
    { NULL }
};