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/*

 * Copyright (c) 2000-2001 Christoph Hellwig.

 * All rights reserved.

 *

 * 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,

 *    without modification.

 * 2. The name of the author may not be used to endorse or promote products

 *    derived from this software without specific prior written permission.

 *

 * Alternatively, this software may be distributed under the terms of the

 * GNU General Public License ("GPL").

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.

 */

/*

 * Veritas filesystem driver - superblock related routines.

 */

#include <linux/init.h>

#include <linux/module.h>

#include <linux/blkdev.h>

#include <linux/fs.h>

#include <linux/buffer_head.h>

#include <linux/kernel.h>

#include <linux/slab.h>

#include <linux/stat.h>

#include <linux/vfs.h>

#include <linux/mount.h>

#include "vxfs.h"

#include "vxfs_extern.h"

#include "vxfs_dir.h"

#include "vxfs_inode.h"

MODULE_AUTHOR("Christoph Hellwig");

MODULE_DESCRIPTION("Veritas Filesystem (VxFS) driver");

MODULE_LICENSE("Dual BSD/GPL");

MODULE_ALIAS("vxfs"); /* makes mount -t vxfs autoload the module */

static void             vxfs_put_super(struct super_block *);

static int              vxfs_statfs(struct dentry *, struct kstatfs *);

static int              vxfs_remount(struct super_block *, int *, char *);

static const struct super_operations vxfs_super_ops = {

        .read_inode =           vxfs_read_inode,

        .clear_inode =          vxfs_clear_inode,

        .put_super =            vxfs_put_super,

        .statfs =               vxfs_statfs,

        .remount_fs =           vxfs_remount,

};

/**

 * vxfs_put_super - free superblock resources

 * @sbp:        VFS superblock.

 *

 * Description:

 *   vxfs_put_super frees all resources allocated for @sbp

 *   after the last instance of the filesystem is unmounted.

 */

static void

vxfs_put_super(struct super_block *sbp)

{

        struct vxfs_sb_info     *infp = VXFS_SBI(sbp);

        vxfs_put_fake_inode(infp->vsi_fship);

        vxfs_put_fake_inode(infp->vsi_ilist);

        vxfs_put_fake_inode(infp->vsi_stilist);

        brelse(infp->vsi_bp);

        kfree(infp);

}

/**

 * vxfs_statfs - get filesystem information

 * @dentry:     VFS dentry to locate superblock

 * @bufp:       output buffer

 *

 * Description:

 *   vxfs_statfs fills the statfs buffer @bufp with information

 *   about the filesystem described by @dentry.

 *

 * Returns:

 *   Zero.

 *

 * Locking:

 *   No locks held.

 *

 * Notes:

 *   This is everything but complete...

 */

static int

vxfs_statfs(struct dentry *dentry, struct kstatfs *bufp)

{

        struct vxfs_sb_info             *infp = VXFS_SBI(dentry->d_sb);

        bufp->f_type = VXFS_SUPER_MAGIC;

        bufp->f_bsize = dentry->d_sb->s_blocksize;

        bufp->f_blocks = infp->vsi_raw->vs_dsize;

        bufp->f_bfree = infp->vsi_raw->vs_free;

        bufp->f_bavail = 0;

        bufp->f_files = 0;

        bufp->f_ffree = infp->vsi_raw->vs_ifree;

        bufp->f_namelen = VXFS_NAMELEN;

        return 0;

}

static int vxfs_remount(struct super_block *sb, int *flags, char *data)

{

        *flags |= MS_RDONLY;

        return 0;

}

/**

 * vxfs_read_super - read superblock into memory and initalize filesystem

 * @sbp:                VFS superblock (to fill)

 * @dp:                 fs private mount data

 * @silent:             do not complain loudly when sth is wrong

 *

 * Description:

 *   We are called on the first mount of a filesystem to read the

 *   superblock into memory and do some basic setup.

 *

 * Returns:

 *   The superblock on success, else %NULL.

 *

 * Locking:

 *   We are under the bkl and @sbp->s_lock.

 */

static int vxfs_fill_super(struct super_block *sbp, void *dp, int silent)

{

        struct vxfs_sb_info     *infp;

        struct vxfs_sb          *rsbp;

        struct buffer_head      *bp = NULL;

        u_long                  bsize;

        struct inode *root;

        sbp->s_flags |= MS_RDONLY;

        infp = kzalloc(sizeof(*infp), GFP_KERNEL);

        if (!infp) {

                printk(KERN_WARNING "vxfs: unable to allocate incore superblock\n");

                return -ENOMEM;

        }

        bsize = sb_min_blocksize(sbp, BLOCK_SIZE);

        if (!bsize) {

                printk(KERN_WARNING "vxfs: unable to set blocksize\n");

                goto out;

        }

        bp = sb_bread(sbp, 1);

        if (!bp || !buffer_mapped(bp)) {

                if (!silent) {

                        printk(KERN_WARNING

                                "vxfs: unable to read disk superblock\n");

                }

                goto out;

        }

        rsbp = (struct vxfs_sb *)bp->b_data;

        if (rsbp->vs_magic != VXFS_SUPER_MAGIC) {

                if (!silent)

                        printk(KERN_NOTICE "vxfs: WRONG superblock magic\n");

                goto out;

        }

        if ((rsbp->vs_version < 2 || rsbp->vs_version > 4) && !silent) {

                printk(KERN_NOTICE "vxfs: unsupported VxFS version (%d)\n",

                       rsbp->vs_version);

                goto out;

        }

#ifdef DIAGNOSTIC

        printk(KERN_DEBUG "vxfs: supported VxFS version (%d)\n", rsbp->vs_version);

        printk(KERN_DEBUG "vxfs: blocksize: %d\n", rsbp->vs_bsize);

#endif

        sbp->s_magic = rsbp->vs_magic;

        sbp->s_fs_info = infp;

        infp->vsi_raw = rsbp;

        infp->vsi_bp = bp;

        infp->vsi_oltext = rsbp->vs_oltext[0];

        infp->vsi_oltsize = rsbp->vs_oltsize;

        if (!sb_set_blocksize(sbp, rsbp->vs_bsize)) {

                printk(KERN_WARNING "vxfs: unable to set final block size\n");

                goto out;

        }

        if (vxfs_read_olt(sbp, bsize)) {

                printk(KERN_WARNING "vxfs: unable to read olt\n");

                goto out;

        }

        if (vxfs_read_fshead(sbp)) {

                printk(KERN_WARNING "vxfs: unable to read fshead\n");

                goto out;

        }

        sbp->s_op = &vxfs_super_ops;

        root = iget(sbp, VXFS_ROOT_INO);

        sbp->s_root = d_alloc_root(root);

        if (!sbp->s_root) {

                iput(root);

                printk(KERN_WARNING "vxfs: unable to get root dentry.\n");

                goto out_free_ilist;

        }

        return 0;

out_free_ilist:

        vxfs_put_fake_inode(infp->vsi_fship);

        vxfs_put_fake_inode(infp->vsi_ilist);

        vxfs_put_fake_inode(infp->vsi_stilist);

out:

        brelse(bp);

        kfree(infp);

        return -EINVAL;

}

/*

 * The usual module blurb.

 */

static int vxfs_get_sb(struct file_system_type *fs_type,

        int flags, const char *dev_name, void *data, struct vfsmount *mnt)

{

        return get_sb_bdev(fs_type, flags, dev_name, data, vxfs_fill_super,

                           mnt);

}

static struct file_system_type vxfs_fs_type = {

        .owner          = THIS_MODULE,

        .name           = "vxfs",

        .get_sb         = vxfs_get_sb,

        .kill_sb        = kill_block_super,

        .fs_flags       = FS_REQUIRES_DEV,

};

static int __init

vxfs_init(void)

{

        int rv;

        vxfs_inode_cachep = kmem_cache_create("vxfs_inode",

                        sizeof(struct vxfs_inode_info), 0,

                        SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, NULL);

        if (!vxfs_inode_cachep)

                return -ENOMEM;

        rv = register_filesystem(&vxfs_fs_type);

        if (rv < 0)

                kmem_cache_destroy(vxfs_inode_cachep);

        return rv;

}

static void __exit

vxfs_cleanup(void)

{

        unregister_filesystem(&vxfs_fs_type);

        kmem_cache_destroy(vxfs_inode_cachep);

}

module_init(vxfs_init);

module_exit(vxfs_cleanup);