xfs_super.c

来自「linux-2.4.29操作系统的源码」· C语言 代码 · 共 1,067 行 · 第 1/2 页

			timeleft = (xfs_syncd_centisecs * HZ) / 100;
			INIT_LIST_HEAD(&vfsp->vfs_sync_work.w_list);
			list_add_tail(&vfsp->vfs_sync_work.w_list,
					&vfsp->vfs_sync_list);
		}
		list_for_each_entry_safe(work, n, &vfsp->vfs_sync_list, w_list)
			list_move(&work->w_list, &tmp);
		spin_unlock(&vfsp->vfs_sync_lock);

		list_for_each_entry_safe(work, n, &tmp, w_list) {
			(*work->w_syncer)(vfsp, work->w_data);
			list_del(&work->w_list);
			if (work == &vfsp->vfs_sync_work)
				continue;
			kmem_free(work, sizeof(struct vfs_sync_work));
		}
	}

	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) {
			printk(KERN_WARNING
			       "XFS: detected filehandle without "
			       "parent inode generation information.");
			return ERR_PTR(-ESTALE);
		}

		xfid.fid_gen = data[3];
		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");