inode.c

linux 内核源代码

/*
 * smb_show_options() is for displaying mount options in /proc/mounts.
 * It tries to avoid showing settings that were not changed from their
 * defaults.
 */
static int
smb_show_options(struct seq_file *s, struct vfsmount *m)
{
	struct smb_mount_data_kernel *mnt = SMB_SB(m->mnt_sb)->mnt;
	int i;

	for (i = 0; opts[i].name != NULL; i++)
		if (mnt->flags & opts[i].flag)
			seq_printf(s, ",%s", opts[i].name);

	if (mnt->flags & SMB_MOUNT_UID)
		seq_printf(s, ",uid=%d", mnt->uid);
	if (mnt->flags & SMB_MOUNT_GID)
		seq_printf(s, ",gid=%d", mnt->gid);
	if (mnt->mounted_uid != 0)
		seq_printf(s, ",mounted_uid=%d", mnt->mounted_uid);

	/* 
	 * Defaults for file_mode and dir_mode are unknown to us; they
	 * depend on the current umask of the user doing the mount.
	 */
	if (mnt->flags & SMB_MOUNT_FMODE)
		seq_printf(s, ",file_mode=%04o", mnt->file_mode & S_IRWXUGO);
	if (mnt->flags & SMB_MOUNT_DMODE)
		seq_printf(s, ",dir_mode=%04o", mnt->dir_mode & S_IRWXUGO);

	if (strcmp(mnt->codepage.local_name, CONFIG_NLS_DEFAULT))
		seq_printf(s, ",iocharset=%s", mnt->codepage.local_name);
	if (strcmp(mnt->codepage.remote_name, SMB_NLS_REMOTE))
		seq_printf(s, ",codepage=%s", mnt->codepage.remote_name);

	if (mnt->ttl != SMB_TTL_DEFAULT)
		seq_printf(s, ",ttl=%d", mnt->ttl);

	return 0;
}

static void
smb_unload_nls(struct smb_sb_info *server)
{
	if (server->remote_nls) {
		unload_nls(server->remote_nls);
		server->remote_nls = NULL;
	}
	if (server->local_nls) {
		unload_nls(server->local_nls);
		server->local_nls = NULL;
	}
}

static void
smb_put_super(struct super_block *sb)
{
	struct smb_sb_info *server = SMB_SB(sb);

	smb_lock_server(server);
	server->state = CONN_INVALID;
	smbiod_unregister_server(server);

	smb_close_socket(server);

	if (server->conn_pid)
		kill_pid(server->conn_pid, SIGTERM, 1);

	kfree(server->ops);
	smb_unload_nls(server);
	sb->s_fs_info = NULL;
	smb_unlock_server(server);
	put_pid(server->conn_pid);
	kfree(server);
}

static int smb_fill_super(struct super_block *sb, void *raw_data, int silent)
{
	struct smb_sb_info *server;
	struct smb_mount_data_kernel *mnt;
	struct smb_mount_data *oldmnt;
	struct inode *root_inode;
	struct smb_fattr root;
	int ver;
	void *mem;

	if (!raw_data)
		goto out_no_data;

	oldmnt = (struct smb_mount_data *) raw_data;
	ver = oldmnt->version;
	if (ver != SMB_MOUNT_OLDVERSION && cpu_to_be32(ver) != SMB_MOUNT_ASCII)
		goto out_wrong_data;

	sb->s_flags |= MS_NODIRATIME;
	sb->s_blocksize = 1024;	/* Eh...  Is this correct? */
	sb->s_blocksize_bits = 10;
	sb->s_magic = SMB_SUPER_MAGIC;
	sb->s_op = &smb_sops;
	sb->s_time_gran = 100;

	server = kzalloc(sizeof(struct smb_sb_info), GFP_KERNEL);
	if (!server)
		goto out_no_server;
	sb->s_fs_info = server;

	server->super_block = sb;
	server->mnt = NULL;
	server->sock_file = NULL;
	init_waitqueue_head(&server->conn_wq);
	init_MUTEX(&server->sem);
	INIT_LIST_HEAD(&server->entry);
	INIT_LIST_HEAD(&server->xmitq);
	INIT_LIST_HEAD(&server->recvq);
	server->conn_error = 0;
	server->conn_pid = NULL;
	server->state = CONN_INVALID; /* no connection yet */
	server->generation = 0;

	/* Allocate the global temp buffer and some superblock helper structs */
	/* FIXME: move these to the smb_sb_info struct */
	VERBOSE("alloc chunk = %lu\n", sizeof(struct smb_ops) +
		sizeof(struct smb_mount_data_kernel));
	mem = kmalloc(sizeof(struct smb_ops) +
		      sizeof(struct smb_mount_data_kernel), GFP_KERNEL);
	if (!mem)
		goto out_no_mem;

	server->ops = mem;
	smb_install_null_ops(server->ops);
	server->mnt = mem + sizeof(struct smb_ops);

	/* Setup NLS stuff */
	server->remote_nls = NULL;
	server->local_nls = NULL;

	mnt = server->mnt;

	memset(mnt, 0, sizeof(struct smb_mount_data_kernel));
	strlcpy(mnt->codepage.local_name, CONFIG_NLS_DEFAULT,
		SMB_NLS_MAXNAMELEN);
	strlcpy(mnt->codepage.remote_name, SMB_NLS_REMOTE,
		SMB_NLS_MAXNAMELEN);

	mnt->ttl = SMB_TTL_DEFAULT;
	if (ver == SMB_MOUNT_OLDVERSION) {
		mnt->version = oldmnt->version;

		SET_UID(mnt->uid, oldmnt->uid);
		SET_GID(mnt->gid, oldmnt->gid);

		mnt->file_mode = (oldmnt->file_mode & S_IRWXUGO) | S_IFREG;
		mnt->dir_mode = (oldmnt->dir_mode & S_IRWXUGO) | S_IFDIR;

		mnt->flags = (oldmnt->file_mode >> 9) | SMB_MOUNT_UID |
			SMB_MOUNT_GID | SMB_MOUNT_FMODE | SMB_MOUNT_DMODE;
	} else {
		mnt->file_mode = S_IRWXU | S_IRGRP | S_IXGRP |
				S_IROTH | S_IXOTH | S_IFREG;
		mnt->dir_mode = S_IRWXU | S_IRGRP | S_IXGRP |
				S_IROTH | S_IXOTH | S_IFDIR;
		if (parse_options(mnt, raw_data))
			goto out_bad_option;
	}
	mnt->mounted_uid = current->uid;
	smb_setcodepage(server, &mnt->codepage);

	/*
	 * Display the enabled options
	 * Note: smb_proc_getattr uses these in 2.4 (but was changed in 2.2)
	 */
	if (mnt->flags & SMB_MOUNT_OLDATTR)
		printk("SMBFS: Using core getattr (Win 95 speedup)\n");
	else if (mnt->flags & SMB_MOUNT_DIRATTR)
		printk("SMBFS: Using dir ff getattr\n");

	if (smbiod_register_server(server) < 0) {
		printk(KERN_ERR "smbfs: failed to start smbiod\n");
		goto out_no_smbiod;
	}

	/*
	 * Keep the super block locked while we get the root inode.
	 */
	smb_init_root_dirent(server, &root, sb);
	root_inode = smb_iget(sb, &root);
	if (!root_inode)
		goto out_no_root;

	sb->s_root = d_alloc_root(root_inode);
	if (!sb->s_root)
		goto out_no_root;

	smb_new_dentry(sb->s_root);

	return 0;

out_no_root:
	iput(root_inode);
out_no_smbiod:
	smb_unload_nls(server);
out_bad_option:
	kfree(mem);
out_no_mem:
	if (!server->mnt)
		printk(KERN_ERR "smb_fill_super: allocation failure\n");
	sb->s_fs_info = NULL;
	kfree(server);
	goto out_fail;
out_wrong_data:
	printk(KERN_ERR "smbfs: mount_data version %d is not supported\n", ver);
	goto out_fail;
out_no_data:
	printk(KERN_ERR "smb_fill_super: missing data argument\n");
out_fail:
	return -EINVAL;
out_no_server:
	printk(KERN_ERR "smb_fill_super: cannot allocate struct smb_sb_info\n");
	return -ENOMEM;
}

static int
smb_statfs(struct dentry *dentry, struct kstatfs *buf)
{
	int result;
	
	lock_kernel();

	result = smb_proc_dskattr(dentry, buf);

	unlock_kernel();

	buf->f_type = SMB_SUPER_MAGIC;
	buf->f_namelen = SMB_MAXPATHLEN;
	return result;
}

int smb_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
{
	int err = smb_revalidate_inode(dentry);
	if (!err)
		generic_fillattr(dentry->d_inode, stat);
	return err;
}

int
smb_notify_change(struct dentry *dentry, struct iattr *attr)
{
	struct inode *inode = dentry->d_inode;
	struct smb_sb_info *server = server_from_dentry(dentry);
	unsigned int mask = (S_IFREG | S_IFDIR | S_IRWXUGO);
	int error, changed, refresh = 0;
	struct smb_fattr fattr;

	lock_kernel();

	error = smb_revalidate_inode(dentry);
	if (error)
		goto out;

	if ((error = inode_change_ok(inode, attr)) < 0)
		goto out;

	error = -EPERM;
	if ((attr->ia_valid & ATTR_UID) && (attr->ia_uid != server->mnt->uid))
		goto out;

	if ((attr->ia_valid & ATTR_GID) && (attr->ia_uid != server->mnt->gid))
		goto out;

	if ((attr->ia_valid & ATTR_MODE) && (attr->ia_mode & ~mask))
		goto out;

	if ((attr->ia_valid & ATTR_SIZE) != 0) {
		VERBOSE("changing %s/%s, old size=%ld, new size=%ld\n",
			DENTRY_PATH(dentry),
			(long) inode->i_size, (long) attr->ia_size);

		filemap_write_and_wait(inode->i_mapping);

		error = smb_open(dentry, O_WRONLY);
		if (error)
			goto out;
		error = server->ops->truncate(inode, attr->ia_size);
		if (error)
			goto out;
		error = vmtruncate(inode, attr->ia_size);
		if (error)
			goto out;
		refresh = 1;
	}

	if (server->opt.capabilities & SMB_CAP_UNIX) {
		/* For now we don't want to set the size with setattr_unix */
		attr->ia_valid &= ~ATTR_SIZE;
		/* FIXME: only call if we actually want to set something? */
		error = smb_proc_setattr_unix(dentry, attr, 0, 0);
		if (!error)
			refresh = 1;

		goto out;
	}

	/*
	 * Initialize the fattr and check for changed fields.
	 * Note: CTIME under SMB is creation time rather than
	 * change time, so we don't attempt to change it.
	 */
	smb_get_inode_attr(inode, &fattr);

	changed = 0;
	if ((attr->ia_valid & ATTR_MTIME) != 0) {
		fattr.f_mtime = attr->ia_mtime;
		changed = 1;
	}
	if ((attr->ia_valid & ATTR_ATIME) != 0) {
		fattr.f_atime = attr->ia_atime;
		/* Earlier protocols don't have an access time */
		if (server->opt.protocol >= SMB_PROTOCOL_LANMAN2)
			changed = 1;
	}
	if (changed) {
		error = smb_proc_settime(dentry, &fattr);
		if (error)
			goto out;
		refresh = 1;
	}

	/*
	 * Check for mode changes ... we're extremely limited in
	 * what can be set for SMB servers: just the read-only bit.
	 */
	if ((attr->ia_valid & ATTR_MODE) != 0) {
		VERBOSE("%s/%s mode change, old=%x, new=%x\n",
			DENTRY_PATH(dentry), fattr.f_mode, attr->ia_mode);
		changed = 0;
		if (attr->ia_mode & S_IWUSR) {
			if (fattr.attr & aRONLY) {
				fattr.attr &= ~aRONLY;
				changed = 1;
			}
		} else {
			if (!(fattr.attr & aRONLY)) {
				fattr.attr |= aRONLY;
				changed = 1;
			}
		}
		if (changed) {
			error = smb_proc_setattr(dentry, &fattr);
			if (error)
				goto out;
			refresh = 1;
		}
	}
	error = 0;

out:
	if (refresh)
		smb_refresh_inode(dentry);
	unlock_kernel();
	return error;
}

static int smb_get_sb(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *data, struct vfsmount *mnt)
{
	return get_sb_nodev(fs_type, flags, data, smb_fill_super, mnt);
}

static struct file_system_type smb_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "smbfs",
	.get_sb		= smb_get_sb,
	.kill_sb	= kill_anon_super,
	.fs_flags	= FS_BINARY_MOUNTDATA,
};

static int __init init_smb_fs(void)
{
	int err;
	DEBUG1("registering ...\n");

	err = init_inodecache();
	if (err)
		goto out_inode;
	err = smb_init_request_cache();
	if (err)
		goto out_request;
	err = register_filesystem(&smb_fs_type);
	if (err)
		goto out;
	return 0;
out:
	smb_destroy_request_cache();
out_request:
	destroy_inodecache();
out_inode:
	return err;
}

static void __exit exit_smb_fs(void)
{
	DEBUG1("unregistering ...\n");
	unregister_filesystem(&smb_fs_type);
	smb_destroy_request_cache();
	destroy_inodecache();
}

module_init(init_smb_fs)
module_exit(exit_smb_fs)
MODULE_LICENSE("GPL");