/*
 * Copyright (c) 2000-2004 Silicon Graphics, Inc.  All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Further, this software is distributed without any warranty that it is
 * free of the rightful claim of any third person regarding infringement
 * or the like.  Any license provided herein, whether implied or
 * otherwise, applies only to this software file.  Patent licenses, if
 * any, provided herein do not apply to combinations of this program with
 * other software, or any other product whatsoever.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write the Free Software Foundation, Inc., 59
 * Temple Place - Suite 330, Boston MA 02111-1307, USA.
 *
 * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
 * Mountain View, CA  94043, or:
 *
 * http://www.sgi.com
 *
 * For further information regarding this notice, see:
 *
 * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
 */

#include "xfs.h"

#include "xfs_inum.h"
#include "xfs_log.h"
#include "xfs_clnt.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_dir.h"
#include "xfs_dir2.h"
#include "xfs_alloc.h"
#include "xfs_dmapi.h"
#include "xfs_quota.h"
#include "xfs_mount.h"
#include "xfs_alloc_btree.h"
#include "xfs_bmap_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_btree.h"
#include "xfs_ialloc.h"
#include "xfs_attr_sf.h"
#include "xfs_dir_sf.h"
#include "xfs_dir2_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_bmap.h"
#include "xfs_bit.h"
#include "xfs_rtalloc.h"
#include "xfs_error.h"
#include "xfs_itable.h"
#include "xfs_rw.h"
#include "xfs_acl.h"
#include "xfs_cap.h"
#include "xfs_mac.h"
#include "xfs_attr.h"
#include "xfs_buf_item.h"
#include "xfs_utils.h"
#include "xfs_version.h"

#include <linux/init.h>

STATIC struct quotactl_ops linvfs_qops;
STATIC struct super_operations linvfs_sops;
STATIC kmem_zone_t *linvfs_inode_zone;
STATIC kmem_shaker_t xfs_inode_shaker;

STATIC struct xfs_mount_args *
xfs_args_allocate(
        struct super_block      *sb)
{
        struct xfs_mount_args   *args;

        args = kmem_zalloc(sizeof(struct xfs_mount_args), KM_SLEEP);
        args->logbufs = args->logbufsize = -1;
        strncpy(args->fsname, bdevname(sb->s_dev), MAXNAMELEN);

        /* Copy the already-parsed mount(2) flags we're interested in */
        if (sb->s_flags & MS_NOATIME)
                args->flags |= XFSMNT_NOATIME;

        /* Default to 32 bit inodes on Linux all the time */
        args->flags |= XFSMNT_32BITINODES;

        return args;
}

__uint64_t
xfs_max_file_offset(
        unsigned int            blockshift)
{
        unsigned int            pagefactor = 1;
        unsigned int            bitshift = BITS_PER_LONG - 1;

        /* Figure out maximum filesize, on Linux this can depend on
         * the filesystem blocksize (on 32 bit platforms).
         * __block_prepare_write does this in an [unsigned] long...
         *      page->index << (PAGE_CACHE_SHIFT - bbits)
         * So, for page sized blocks (4K on 32 bit platforms),
         * this wraps at around 8Tb (hence MAX_LFS_FILESIZE which is
         *      (((u64)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1)
         * but for smaller blocksizes it is less (bbits = log2 bsize).
         * Note1: get_block_t takes a long (implicit cast from above)
         * Note2: The Large Block Device (LBD and HAVE_SECTOR_T) patch
         * can optionally convert the [unsigned] long from above into
         * an [unsigned] long long.
         */

#if BITS_PER_LONG == 32
        pagefactor = PAGE_CACHE_SIZE >> (PAGE_CACHE_SHIFT - blockshift);
#endif

        return (((__uint64_t)pagefactor) << bitshift) - 1;
}

STATIC __inline__ void
xfs_set_inodeops(
        struct inode            *inode)
{
        vnode_t                 *vp = LINVFS_GET_VP(inode);

        if (vp->v_type == VNON) {
                remove_inode_hash(inode);
                make_bad_inode(inode);
        } else if (S_ISREG(inode->i_mode)) {
                inode->i_op = &linvfs_file_inode_operations;
                inode->i_fop = &linvfs_file_operations;
                inode->i_mapping->a_ops = &linvfs_aops;
        } else if (S_ISDIR(inode->i_mode)) {
                inode->i_op = &linvfs_dir_inode_operations;
                inode->i_fop = &linvfs_dir_operations;
        } else if (S_ISLNK(inode->i_mode)) {
                inode->i_op = &linvfs_symlink_inode_operations;
                if (inode->i_blocks)
                        inode->i_mapping->a_ops = &linvfs_aops;
        } else {
                inode->i_op = &linvfs_file_inode_operations;
                init_special_inode(inode, inode->i_mode,
                                        kdev_t_to_nr(inode->i_rdev));
        }
}

STATIC __inline__ void
xfs_revalidate_inode(
        xfs_mount_t             *mp,
        vnode_t                 *vp,
        xfs_inode_t             *ip)
{
        struct inode            *inode = LINVFS_GET_IP(vp);

        inode->i_mode   = (ip->i_d.di_mode & MODEMASK) | VTTOIF(vp->v_type);
        inode->i_nlink  = ip->i_d.di_nlink;
        inode->i_uid    = ip->i_d.di_uid;
        inode->i_gid    = ip->i_d.di_gid;
        if (((1 << vp->v_type) & ((1<<VBLK) | (1<<VCHR))) == 0) {
                inode->i_rdev = NODEV;
        } else {
                xfs_dev_t dev = ip->i_df.if_u2.if_rdev;
                inode->i_rdev = XFS_DEV_TO_KDEVT(dev);
        }
        inode->i_blksize = PAGE_CACHE_SIZE;
        inode->i_generation = ip->i_d.di_gen;
        i_size_write(inode, ip->i_d.di_size);
        inode->i_blocks =
                XFS_FSB_TO_BB(mp, ip->i_d.di_nblocks + ip->i_delayed_blks);
        inode->i_atime  = ip->i_d.di_atime.t_sec;
        inode->i_mtime  = ip->i_d.di_mtime.t_sec;
        inode->i_ctime  = ip->i_d.di_ctime.t_sec;
        if (ip->i_d.di_flags & XFS_DIFLAG_IMMUTABLE)
                inode->i_flags |= S_IMMUTABLE;
        else
                inode->i_flags &= ~S_IMMUTABLE;
        if (ip->i_d.di_flags & XFS_DIFLAG_APPEND)
                inode->i_flags |= S_APPEND;
        else
                inode->i_flags &= ~S_APPEND;
        if (ip->i_d.di_flags & XFS_DIFLAG_SYNC)
                inode->i_flags |= S_SYNC;
        else
                inode->i_flags &= ~S_SYNC;
        if (ip->i_d.di_flags & XFS_DIFLAG_NOATIME)
                inode->i_flags |= S_NOATIME;
        else
                inode->i_flags &= ~S_NOATIME;

        vp->v_flag &= ~VMODIFIED;
}

void
xfs_initialize_vnode(
        bhv_desc_t              *bdp,
        vnode_t                 *vp,
        bhv_desc_t              *inode_bhv,
        int                     unlock)
{
        xfs_inode_t             *ip = XFS_BHVTOI(inode_bhv);
        struct inode            *inode = LINVFS_GET_IP(vp);

        if (!inode_bhv->bd_vobj) {
                vp->v_vfsp = bhvtovfs(bdp);
                bhv_desc_init(inode_bhv, ip, vp, &xfs_vnodeops);
                bhv_insert(VN_BHV_HEAD(vp), inode_bhv);
        }

        vp->v_type = IFTOVT(ip->i_d.di_mode);

        /* Have we been called during the new inode create process,
         * in which case we are too early to fill in the Linux inode.
         */
        if (vp->v_type == VNON)
                return;

        xfs_revalidate_inode(XFS_BHVTOM(bdp), vp, ip);

        /* For new inodes we need to set the ops vectors,
         * and unlock the inode.
         */
        if (unlock && (inode->i_state & I_NEW)) {
                xfs_set_inodeops(inode);
                unlock_new_inode(inode);
        }
}

int
xfs_inode_shake(
        int             priority,
        unsigned int    gfp_mask)
{
        int             pages;

        pages = kmem_zone_shrink(linvfs_inode_zone);
        pages += kmem_zone_shrink(xfs_inode_zone);
        return pages;
}

struct inode *
xfs_get_inode(
        bhv_desc_t      *bdp,
        xfs_ino_t       ino,
        int             flags)
{
        struct vfs      *vfsp = bhvtovfs(bdp);

        return iget_locked(vfsp->vfs_super, ino);
}

void
xfs_flush_inode(
        xfs_inode_t     *ip)
{
        struct inode    *inode = LINVFS_GET_IP(XFS_ITOV(ip));

        filemap_fdatawrite(inode->i_mapping);
}

void
xfs_flush_device(
        xfs_inode_t     *ip)
{
        struct inode    *inode = LINVFS_GET_IP(XFS_ITOV(ip));

        fsync_no_super(inode->i_dev);
        xfs_log_force(ip->i_mount, (xfs_lsn_t)0, XFS_LOG_FORCE|XFS_LOG_SYNC);
}

struct dentry *
d_alloc_anon(struct inode *inode)
{
        struct dentry *dentry;

        spin_lock(&dcache_lock);
        list_for_each_entry(dentry, &inode->i_dentry, d_alias) {
                if (!(dentry->d_flags & DCACHE_NFSD_DISCONNECTED))
                        goto found;
        }
        spin_unlock(&dcache_lock);

        dentry = d_alloc_root(inode);
        if (likely(dentry != NULL))
                dentry->d_flags |= DCACHE_NFSD_DISCONNECTED;
        return dentry;
 found:
        dget_locked(dentry);
        dentry->d_vfs_flags |= DCACHE_REFERENCED;
        spin_unlock(&dcache_lock);
        iput(inode);
        return dentry;
}

/*ARGSUSED*/
int
xfs_blkdev_get(
        xfs_mount_t             *mp,
        const char              *name,
        struct block_device     **bdevp)
{
        struct nameidata        nd;
        int                     error;

        error = path_lookup(name, LOOKUP_POSITIVE|LOOKUP_FOLLOW, &nd);
        if (error) {
                printk("XFS: Invalid device [%s], error=%d\n", name, error);
                return -error;
        }

        /* I think we actually want bd_acquire here..  --hch */
        *bdevp = bdget(kdev_t_to_nr(nd.dentry->d_inode->i_rdev));
        if (*bdevp)
                error = blkdev_get(*bdevp, FMODE_READ|FMODE_WRITE, 0, BDEV_FS);
        else
                error = -ENOMEM;

        path_release(&nd);
        return -error;
}

void
xfs_blkdev_put(
        struct block_device     *bdev)
{
        if (bdev)
                blkdev_put(bdev, BDEV_FS);
}

STATIC struct inode *
linvfs_alloc_inode(
        struct super_block      *sb)
{
        vnode_t                 *vp;

        vp = (vnode_t *)kmem_cache_alloc(linvfs_inode_zone, 
                kmem_flags_convert(KM_SLEEP));
        if (!vp)
                return NULL;
        return LINVFS_GET_IP(vp);
}

STATIC void
linvfs_destroy_inode(
        struct inode            *inode)
{
        kmem_cache_free(linvfs_inode_zone, LINVFS_GET_VP(inode));
}

#define VNODE_SIZE      \
        (sizeof(vnode_t) - sizeof(struct inode) + offsetof(struct inode, u))

STATIC void
init_once(
        void                    *data,
        kmem_cache_t            *cachep,
        unsigned long           flags)
{
        vnode_t                 *vp = (vnode_t *)data;

        if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
            SLAB_CTOR_CONSTRUCTOR) {
                struct inode *inode = LINVFS_GET_IP(vp);
                memset(vp, 0, VNODE_SIZE);
                __inode_init_once(inode);
        }
}

STATIC int
init_inodecache( void )
{
        linvfs_inode_zone = kmem_cache_create("linvfs_icache",
                                VNODE_SIZE, 0, SLAB_HWCACHE_ALIGN,
                                init_once, NULL);
        if (linvfs_inode_zone == NULL)
                return -ENOMEM;
        return 0;
}

STATIC void
destroy_inodecache( void )
{
        if (kmem_cache_destroy(linvfs_inode_zone))
                printk(KERN_WARNING "%s: cache still in use!\n", __FUNCTION__);
}

/*
 * Attempt to flush the inode, this will actually fail
 * if the inode is pinned, but we dirty the inode again
 * at the point when it is unpinned after a log write,
 * since this is when the inode itself becomes flushable. 
 */
STATIC void
linvfs_write_inode(
        struct inode            *inode,
        int                     sync)
{
        vnode_t                 *vp = LINVFS_GET_VP(inode);
        int                     error, flags = FLUSH_INODE;

        if (vp) {
                vn_trace_entry(vp, __FUNCTION__, (inst_t *)__return_address);
                if (sync)
                        flags |= FLUSH_SYNC;
                VOP_IFLUSH(vp, flags, error);
        }
}

STATIC void
linvfs_clear_inode(
        struct inode            *inode)
{
        vnode_t                 *vp = LINVFS_GET_VP(inode);

        if (vp) {
                vn_rele(vp);
                vn_trace_entry(vp, __FUNCTION__, (inst_t *)__return_address);
                /*
                 * Do all our cleanup, and remove this vnode.
                 */
                vn_remove(vp);
        }
}


#define SYNCD_FLAGS     (SYNC_FSDATA|SYNC_BDFLUSH|SYNC_ATTR|SYNC_REFCACHE)

STATIC int
xfssyncd(
        void                    *arg)
{
        vfs_t                   *vfsp = (vfs_t *) arg;
        int                     error;

        daemonize();
        reparent_to_init();
        sigmask_lock();
        sigfillset(&current->blocked);
        __recalc_sigpending(current);
        sigmask_unlock();

        sprintf(current->comm, "xfssyncd");

        vfsp->vfs_sync_task = current;
        wmb();
        wake_up(&vfsp->vfs_wait_sync_task);

        for (;;) {
                set_current_state(TASK_INTERRUPTIBLE);
                schedule_timeout((xfs_syncd_centisecs * HZ) / 100);
                if (vfsp->vfs_flag & VFS_UMOUNT)
                        break;
                if (vfsp->vfs_flag & VFS_RDONLY)
                        continue;
                VFS_SYNC(vfsp, SYNCD_FLAGS, NULL, error);
        }

        vfsp->vfs_sync_task = NULL;
        wmb();
        wake_up(&vfsp->vfs_wait_sync_task);

        return 0;
}

STATIC int
linvfs_start_syncd(
        vfs_t                   *vfsp)
{
        int                     pid;

        pid = kernel_thread(xfssyncd, (void *) vfsp,
                        CLONE_VM | CLONE_FS | CLONE_FILES);
        if (pid < 0)
                return pid;
        wait_event(vfsp->vfs_wait_sync_task, vfsp->vfs_sync_task);
        return 0;
}

STATIC void
linvfs_stop_syncd(
        vfs_t                   *vfsp)
{
        vfsp->vfs_flag |= VFS_UMOUNT;
        wmb();

        wake_up_process(vfsp->vfs_sync_task);
        wait_event(vfsp->vfs_wait_sync_task, !vfsp->vfs_sync_task);
}

STATIC void
linvfs_put_super(
        struct super_block      *sb)
{
        vfs_t                   *vfsp = LINVFS_GET_VFS(sb);
        int                     error;

        linvfs_stop_syncd(vfsp);
        VFS_SYNC(vfsp, SYNC_ATTR|SYNC_DELWRI, NULL, error);
        if (!error)
                VFS_UNMOUNT(vfsp, 0, NULL, error);
        if (error) {
                printk("XFS unmount got error %d\n", error);
                printk("%s: vfsp/0x%p left dangling!\n", __FUNCTION__, vfsp);
                return;
        }

        vfs_deallocate(vfsp);
}

STATIC void
linvfs_write_super(
        struct super_block      *sb)
{
        vfs_t                   *vfsp = LINVFS_GET_VFS(sb);
        int                     error;

        if (sb->s_flags & MS_RDONLY) {
                sb->s_dirt = 0; /* paranoia */
                return;
        }
        /* Push the log and superblock a little */
        VFS_SYNC(vfsp, SYNC_FSDATA, NULL, error);
        sb->s_dirt = 0;
}

STATIC int
linvfs_sync_super(
        struct super_block      *sb)
{
        vfs_t           *vfsp = LINVFS_GET_VFS(sb);
        int             error;

        VFS_SYNC(vfsp, SYNC_FSDATA|SYNC_WAIT, NULL, error);
        sb->s_dirt = 0;
        return -error;
}

STATIC int
linvfs_statfs(
        struct super_block      *sb,
        struct statfs           *statp)
{
        vfs_t                   *vfsp = LINVFS_GET_VFS(sb);
        int                     error;

        VFS_STATVFS(vfsp, statp, NULL, error);
        return -error;
}

STATIC int
linvfs_remount(
        struct super_block      *sb,
        int                     *flags,
        char                    *options)
{
        vfs_t                   *vfsp = LINVFS_GET_VFS(sb);
        struct xfs_mount_args   *args = xfs_args_allocate(sb);
        int                     error;

        VFS_PARSEARGS(vfsp, options, args, 1, error);
        if (!error)
                VFS_MNTUPDATE(vfsp, flags, args, error);
        kmem_free(args, sizeof(*args));
        return -error;
}

struct super_block *freeze_bdev(struct block_device *bdev)
{
        struct super_block *sb;
        struct vfs *vfsp;
        int error;

        sb = get_super(to_kdev_t(bdev->bd_dev));
        if (sb && !(sb->s_flags & MS_RDONLY)) {
                vfsp = LINVFS_GET_VFS(sb);

                /* Stop new writers */
                vfsp->vfs_frozen = SB_FREEZE_WRITE;
                wmb();

                /* Flush the refcache */
                VFS_SYNC(vfsp, SYNC_REFCACHE|SYNC_WAIT, NULL, error);

                /* Flush delalloc and delwri data */
                VFS_SYNC(vfsp, SYNC_DELWRI|SYNC_WAIT, NULL, error);

                /* Pause transaction subsystem */
                vfsp->vfs_frozen = SB_FREEZE_TRANS;
                wmb();

                /* Flush any remaining inodes into buffers */
                VFS_SYNC(vfsp, SYNC_ATTR|SYNC_WAIT, NULL, error);

                 /* Push all buffers out to disk */
                sync_buffers(sb->s_dev, 1);

                /* Push the superblock and write an unmount record */
                VFS_FREEZE(vfsp);
        }

        sync_buffers(to_kdev_t(bdev->bd_dev), 1);
        return sb;      /* thaw_bdev releases sb->s_umount */
}

void thaw_bdev(struct block_device *bdev, struct super_block *sb)
{
        if (sb) {
                struct vfs *vfsp = LINVFS_GET_VFS(sb);

                BUG_ON(sb->s_bdev != bdev);

                vfsp->vfs_frozen = SB_UNFROZEN;
                wmb();
                wake_up(&vfsp->vfs_wait_unfrozen);

                drop_super(sb);
        }
}

STATIC void
linvfs_freeze_fs(
        struct super_block      *sb)
{
        if (sb->s_flags & MS_RDONLY)
                return;
        freeze_bdev(sb->s_bdev);
}

STATIC void
linvfs_unfreeze_fs(
        struct super_block      *sb)
{
        thaw_bdev(sb->s_bdev, sb);
}

STATIC int
linvfs_dentry_to_fh(
        struct dentry           *dentry,
        __u32                   *data,
        int                     *lenp,
        int                     need_parent)
{
        struct inode            *inode = dentry->d_inode ;
        vnode_t                 *vp = LINVFS_GET_VP(inode);
        int                     maxlen = *lenp;
        xfs_fid2_t              fid;
        int                     error;

        if (maxlen < 3)
                return 255 ;

        VOP_FID2(vp, (struct fid *)&fid, error);
        data[0] = (__u32)fid.fid_ino;   /* 32 bits of inode is OK */
        data[1] = fid.fid_gen;

        *lenp = 2 ;
        if (maxlen < 4 || ! need_parent)
                return 2 ;

        inode = dentry->d_parent->d_inode ;
        vp = LINVFS_GET_VP(inode);

        VOP_FID2(vp, (struct fid *)&fid, error);
        data[2] = (__u32)fid.fid_ino;   /* 32 bits of inode is OK */
        *lenp = 3 ;
        if (maxlen < 4)
                return 3 ;
        data[3] = fid.fid_gen;
        *lenp = 4 ;
        return 4 ;
}

STATIC struct dentry *
linvfs_fh_to_dentry(
        struct super_block      *sb,
        __u32                   *data,
        int                     len,
        int                     fhtype,
        int                     parent)
{
        vnode_t                 *vp;
        struct inode            *inode = NULL;
        struct dentry           *result;
        xfs_fid2_t              xfid;
        vfs_t                   *vfsp = LINVFS_GET_VFS(sb);
        int                     error;

        xfid.fid_len = sizeof(xfs_fid2_t) - sizeof(xfid.fid_len);
        xfid.fid_pad = 0;

        if (!parent) {
                xfid.fid_gen = data[1];
                xfid.fid_ino = (__u64)data[0];
        } else {
                if (fhtype == 4)
                        xfid.fid_gen = data[3];
                else
                        xfid.fid_gen = 0;
                xfid.fid_ino = (__u64)data[2];
        }

        VFS_VGET(vfsp, &vp, (fid_t *)&xfid, error);
        if (error || vp == NULL)
                return ERR_PTR(-ESTALE) ;

        inode = LINVFS_GET_IP(vp);

        result = d_alloc_anon(inode);
        if (unlikely(result == NULL)) {
                iput(inode);
                return ERR_PTR(-ENOMEM);
        }
        return result;
}

STATIC int
linvfs_show_options(
        struct seq_file         *m,
        struct vfsmount         *mnt)
{
        struct vfs              *vfsp = LINVFS_GET_VFS(mnt->mnt_sb);
        int                     error;

        VFS_SHOWARGS(vfsp, m, error);
        return error;
}

STATIC int
linvfs_getxstate(
        struct super_block      *sb,
        struct fs_quota_stat    *fqs)
{
        struct vfs              *vfsp = LINVFS_GET_VFS(sb);
        int                     error;

        VFS_QUOTACTL(vfsp, Q_XGETQSTAT, 0, (caddr_t)fqs, error);
        return -error;
}

STATIC int
linvfs_setxstate(
        struct super_block      *sb,
        unsigned int            flags,
        int                     op)
{
        struct vfs              *vfsp = LINVFS_GET_VFS(sb);
        int                     error;

        VFS_QUOTACTL(vfsp, op, 0, (caddr_t)&flags, error);
        return -error;
}

STATIC int
linvfs_getxquota(
        struct super_block      *sb,
        int                     type,
        qid_t                   id,
        struct fs_disk_quota    *fdq)
{
        struct vfs              *vfsp = LINVFS_GET_VFS(sb);
        int                     error, getmode;

        getmode = (type == GRPQUOTA) ? Q_XGETGQUOTA : Q_XGETQUOTA;
        VFS_QUOTACTL(vfsp, getmode, id, (caddr_t)fdq, error);
        return -error;
}

STATIC int
linvfs_setxquota(
        struct super_block      *sb,
        int                     type,
        qid_t                   id,
        struct fs_disk_quota    *fdq)
{
        struct vfs              *vfsp = LINVFS_GET_VFS(sb);
        int                     error, setmode;

        setmode = (type == GRPQUOTA) ? Q_XSETGQLIM : Q_XSETQLIM;
        VFS_QUOTACTL(vfsp, setmode, id, (caddr_t)fdq, error);
        return -error;
}

STATIC struct super_block *
linvfs_read_super(
        struct super_block      *sb,
        void                    *data,
        int                     silent)
{
        vnode_t                 *rootvp;
        struct vfs              *vfsp = vfs_allocate();
        struct xfs_mount_args   *args = xfs_args_allocate(sb);
        struct statfs           statvfs;
        int                     error;

        vfsp->vfs_super = sb;
        LINVFS_SET_VFS(sb, vfsp);
        if (sb->s_flags & MS_RDONLY)
                vfsp->vfs_flag |= VFS_RDONLY;
        bhv_insert_all_vfsops(vfsp);

        VFS_PARSEARGS(vfsp, (char *)data, args, 0, error);
        if (error) {
                bhv_remove_all_vfsops(vfsp, 1);
                goto fail_vfsop;
        }

        sb_min_blocksize(sb, BBSIZE);
        sb->s_qcop = &linvfs_qops;
        sb->s_op = &linvfs_sops;

        VFS_MOUNT(vfsp, args, NULL, error);
        if (error) {
                bhv_remove_all_vfsops(vfsp, 1);
                goto fail_vfsop;
        }

        VFS_STATVFS(vfsp, &statvfs, NULL, error);
        if (error)
                goto fail_unmount;

        sb->s_dirt = 1;
        sb->s_magic = statvfs.f_type;
        sb->s_blocksize = statvfs.f_bsize;
        sb->s_blocksize_bits = ffs(statvfs.f_bsize) - 1;
        sb->s_maxbytes = xfs_max_file_offset(sb->s_blocksize_bits);
        set_posix_acl_flag(sb);

        VFS_ROOT(vfsp, &rootvp, error);
        if (error)
                goto fail_unmount;

        sb->s_root = d_alloc_root(LINVFS_GET_IP(rootvp));
        if (!sb->s_root)
                goto fail_vnrele;
        if (is_bad_inode(sb->s_root->d_inode))
                goto fail_vnrele;
        if (linvfs_start_syncd(vfsp))
                goto fail_vnrele;
        vn_trace_exit(rootvp, __FUNCTION__, (inst_t *)__return_address);

        kmem_free(args, sizeof(*args));
        return sb;

fail_vnrele:
        if (sb->s_root) {
                dput(sb->s_root);
                sb->s_root = NULL;
        } else {
                VN_RELE(rootvp);
        }

fail_unmount:
        VFS_UNMOUNT(vfsp, 0, NULL, error);

fail_vfsop:
        vfs_deallocate(vfsp);
        kmem_free(args, sizeof(*args));
        return NULL;
}


STATIC struct super_operations linvfs_sops = {
        .alloc_inode            = linvfs_alloc_inode,
        .destroy_inode          = linvfs_destroy_inode,
        .write_inode            = linvfs_write_inode,
        .clear_inode            = linvfs_clear_inode,
        .put_super              = linvfs_put_super,
        .write_super            = linvfs_write_super,
        .sync_fs                = linvfs_sync_super,
        .write_super_lockfs     = linvfs_freeze_fs,
        .unlockfs               = linvfs_unfreeze_fs,
        .statfs                 = linvfs_statfs,
        .remount_fs             = linvfs_remount,
        .fh_to_dentry           = linvfs_fh_to_dentry,
        .dentry_to_fh           = linvfs_dentry_to_fh,
        .show_options           = linvfs_show_options,
};

STATIC struct quotactl_ops linvfs_qops = {
        .get_xstate             = linvfs_getxstate,
        .set_xstate             = linvfs_setxstate,
        .get_xquota             = linvfs_getxquota,
        .set_xquota             = linvfs_setxquota,
};

STATIC struct file_system_type xfs_fs_type = {
        .owner                  = THIS_MODULE,
        .name                   = "xfs",
        .read_super             = linvfs_read_super,
        .fs_flags               = FS_REQUIRES_DEV,
};


STATIC int __init
init_xfs_fs( void )
{
        int                     error;
        struct sysinfo          si;
        static char             message[] __initdata = KERN_INFO \
                XFS_VERSION_STRING " with " XFS_BUILD_OPTIONS " enabled\n";

        printk(message);

        si_meminfo(&si);
        xfs_physmem = si.totalram;

        ktrace_init(64);

        error = init_inodecache();
        if (error < 0)
                goto undo_inodecache;

        error = pagebuf_init();
        if (error < 0)
                goto undo_pagebuf;

        vn_init();
        xfs_init();
        uuid_init();
        vfs_initdmapi();
        vfs_initquota();

        xfs_inode_shaker = kmem_shake_register(xfs_inode_shake);
        if (!xfs_inode_shaker) {
                error = -ENOMEM;
                goto undo_shaker;
        }

        error = register_filesystem(&xfs_fs_type);
        if (error)
                goto undo_register;
        XFS_DM_INIT(&xfs_fs_type);
        return 0;

undo_register:
        kmem_shake_deregister(xfs_inode_shaker);

undo_shaker:
        pagebuf_terminate();

undo_pagebuf:
        destroy_inodecache();

undo_inodecache:
        return error;
}

STATIC void __exit
exit_xfs_fs( void )
{
        XFS_DM_EXIT(&xfs_fs_type);
        unregister_filesystem(&xfs_fs_type);
        kmem_shake_deregister(xfs_inode_shaker);
        xfs_cleanup();
        vfs_exitquota();
        vfs_exitdmapi();
        pagebuf_terminate();
        destroy_inodecache();
        ktrace_uninit();
}

module_init(init_xfs_fs);
module_exit(exit_xfs_fs);

MODULE_AUTHOR("Silicon Graphics, Inc.");
MODULE_DESCRIPTION(XFS_VERSION_STRING " with " XFS_BUILD_OPTIONS " enabled");
MODULE_LICENSE("GPL");