nfsctl.c

linux 内核源代码

		if (rv)
			return rv;
	}
	sprintf(buf, "%d\n", nfsd_nrthreads());
	return strlen(buf);
}

extern int nfsd_nrpools(void);
extern int nfsd_get_nrthreads(int n, int *);
extern int nfsd_set_nrthreads(int n, int *);

static ssize_t write_pool_threads(struct file *file, char *buf, size_t size)
{
	/* if size > 0, look for an array of number of threads per node
	 * and apply them  then write out number of threads per node as reply
	 */
	char *mesg = buf;
	int i;
	int rv;
	int len;
    	int npools = nfsd_nrpools();
	int *nthreads;

	if (npools == 0) {
		/*
		 * NFS is shut down.  The admin can start it by
		 * writing to the threads file but NOT the pool_threads
		 * file, sorry.  Report zero threads.
		 */
		strcpy(buf, "0\n");
		return strlen(buf);
	}

	nthreads = kcalloc(npools, sizeof(int), GFP_KERNEL);
	if (nthreads == NULL)
		return -ENOMEM;

	if (size > 0) {
		for (i = 0; i < npools; i++) {
			rv = get_int(&mesg, &nthreads[i]);
			if (rv == -ENOENT)
				break;		/* fewer numbers than pools */
			if (rv)
				goto out_free;	/* syntax error */
			rv = -EINVAL;
			if (nthreads[i] < 0)
				goto out_free;
		}
		rv = nfsd_set_nrthreads(i, nthreads);
		if (rv)
			goto out_free;
	}

	rv = nfsd_get_nrthreads(npools, nthreads);
	if (rv)
		goto out_free;

	mesg = buf;
	size = SIMPLE_TRANSACTION_LIMIT;
	for (i = 0; i < npools && size > 0; i++) {
		snprintf(mesg, size, "%d%c", nthreads[i], (i == npools-1 ? '\n' : ' '));
		len = strlen(mesg);
		size -= len;
		mesg += len;
	}

	return (mesg-buf);

out_free:
	kfree(nthreads);
	return rv;
}

static ssize_t write_versions(struct file *file, char *buf, size_t size)
{
	/*
	 * Format:
	 *   [-/+]vers [-/+]vers ...
	 */
	char *mesg = buf;
	char *vers, sign;
	int len, num;
	ssize_t tlen = 0;
	char *sep;

	if (size>0) {
		if (nfsd_serv)
			/* Cannot change versions without updating
			 * nfsd_serv->sv_xdrsize, and reallocing
			 * rq_argp and rq_resp
			 */
			return -EBUSY;
		if (buf[size-1] != '\n')
			return -EINVAL;
		buf[size-1] = 0;

		vers = mesg;
		len = qword_get(&mesg, vers, size);
		if (len <= 0) return -EINVAL;
		do {
			sign = *vers;
			if (sign == '+' || sign == '-')
				num = simple_strtol((vers+1), NULL, 0);
			else
				num = simple_strtol(vers, NULL, 0);
			switch(num) {
			case 2:
			case 3:
			case 4:
				nfsd_vers(num, sign == '-' ? NFSD_CLEAR : NFSD_SET);
				break;
			default:
				return -EINVAL;
			}
			vers += len + 1;
			tlen += len;
		} while ((len = qword_get(&mesg, vers, size)) > 0);
		/* If all get turned off, turn them back on, as
		 * having no versions is BAD
		 */
		nfsd_reset_versions();
	}
	/* Now write current state into reply buffer */
	len = 0;
	sep = "";
	for (num=2 ; num <= 4 ; num++)
		if (nfsd_vers(num, NFSD_AVAIL)) {
			len += sprintf(buf+len, "%s%c%d", sep,
				       nfsd_vers(num, NFSD_TEST)?'+':'-',
				       num);
			sep = " ";
		}
	len += sprintf(buf+len, "\n");
	return len;
}

static ssize_t write_ports(struct file *file, char *buf, size_t size)
{
	if (size == 0) {
		int len = 0;
		lock_kernel();
		if (nfsd_serv)
			len = svc_sock_names(buf, nfsd_serv, NULL);
		unlock_kernel();
		return len;
	}
	/* Either a single 'fd' number is written, in which
	 * case it must be for a socket of a supported family/protocol,
	 * and we use it as an nfsd socket, or
	 * A '-' followed by the 'name' of a socket in which case
	 * we close the socket.
	 */
	if (isdigit(buf[0])) {
		char *mesg = buf;
		int fd;
		int err;
		err = get_int(&mesg, &fd);
		if (err)
			return -EINVAL;
		if (fd < 0)
			return -EINVAL;
		err = nfsd_create_serv();
		if (!err) {
			int proto = 0;
			err = svc_addsock(nfsd_serv, fd, buf, &proto);
			if (err >= 0) {
				err = lockd_up(proto);
				if (err < 0)
					svc_sock_names(buf+strlen(buf)+1, nfsd_serv, buf);
			}
			/* Decrease the count, but don't shutdown the
			 * the service
			 */
			lock_kernel();
			nfsd_serv->sv_nrthreads--;
			unlock_kernel();
		}
		return err < 0 ? err : 0;
	}
	if (buf[0] == '-') {
		char *toclose = kstrdup(buf+1, GFP_KERNEL);
		int len = 0;
		if (!toclose)
			return -ENOMEM;
		lock_kernel();
		if (nfsd_serv)
			len = svc_sock_names(buf, nfsd_serv, toclose);
		unlock_kernel();
		if (len >= 0)
			lockd_down();
		kfree(toclose);
		return len;
	}
	return -EINVAL;
}

int nfsd_max_blksize;

static ssize_t write_maxblksize(struct file *file, char *buf, size_t size)
{
	char *mesg = buf;
	if (size > 0) {
		int bsize;
		int rv = get_int(&mesg, &bsize);
		if (rv)
			return rv;
		/* force bsize into allowed range and
		 * required alignment.
		 */
		if (bsize < 1024)
			bsize = 1024;
		if (bsize > NFSSVC_MAXBLKSIZE)
			bsize = NFSSVC_MAXBLKSIZE;
		bsize &= ~(1024-1);
		lock_kernel();
		if (nfsd_serv && nfsd_serv->sv_nrthreads) {
			unlock_kernel();
			return -EBUSY;
		}
		nfsd_max_blksize = bsize;
		unlock_kernel();
	}
	return sprintf(buf, "%d\n", nfsd_max_blksize);
}

#ifdef CONFIG_NFSD_V4
extern time_t nfs4_leasetime(void);

static ssize_t write_leasetime(struct file *file, char *buf, size_t size)
{
	/* if size > 10 seconds, call
	 * nfs4_reset_lease() then write out the new lease (seconds) as reply
	 */
	char *mesg = buf;
	int rv;

	if (size > 0) {
		int lease;
		rv = get_int(&mesg, &lease);
		if (rv)
			return rv;
		if (lease < 10 || lease > 3600)
			return -EINVAL;
		nfs4_reset_lease(lease);
	}
	sprintf(buf, "%ld\n", nfs4_lease_time());
	return strlen(buf);
}

static ssize_t write_recoverydir(struct file *file, char *buf, size_t size)
{
	char *mesg = buf;
	char *recdir;
	int len, status;

	if (size > PATH_MAX || buf[size-1] != '\n')
		return -EINVAL;
	buf[size-1] = 0;

	recdir = mesg;
	len = qword_get(&mesg, recdir, size);
	if (len <= 0)
		return -EINVAL;

	status = nfs4_reset_recoverydir(recdir);
	return strlen(buf);
}
#endif

/*----------------------------------------------------------------------------*/
/*
 *	populating the filesystem.
 */

static int nfsd_fill_super(struct super_block * sb, void * data, int silent)
{
	static struct tree_descr nfsd_files[] = {
		[NFSD_Svc] = {".svc", &transaction_ops, S_IWUSR},
		[NFSD_Add] = {".add", &transaction_ops, S_IWUSR},
		[NFSD_Del] = {".del", &transaction_ops, S_IWUSR},
		[NFSD_Export] = {".export", &transaction_ops, S_IWUSR},
		[NFSD_Unexport] = {".unexport", &transaction_ops, S_IWUSR},
		[NFSD_Getfd] = {".getfd", &transaction_ops, S_IWUSR|S_IRUSR},
		[NFSD_Getfs] = {".getfs", &transaction_ops, S_IWUSR|S_IRUSR},
		[NFSD_List] = {"exports", &exports_operations, S_IRUGO},
		[NFSD_Fh] = {"filehandle", &transaction_ops, S_IWUSR|S_IRUSR},
		[NFSD_Threads] = {"threads", &transaction_ops, S_IWUSR|S_IRUSR},
		[NFSD_Pool_Threads] = {"pool_threads", &transaction_ops, S_IWUSR|S_IRUSR},
		[NFSD_Versions] = {"versions", &transaction_ops, S_IWUSR|S_IRUSR},
		[NFSD_Ports] = {"portlist", &transaction_ops, S_IWUSR|S_IRUGO},
		[NFSD_MaxBlkSize] = {"max_block_size", &transaction_ops, S_IWUSR|S_IRUGO},
#ifdef CONFIG_NFSD_V4
		[NFSD_Leasetime] = {"nfsv4leasetime", &transaction_ops, S_IWUSR|S_IRUSR},
		[NFSD_RecoveryDir] = {"nfsv4recoverydir", &transaction_ops, S_IWUSR|S_IRUSR},
#endif
		/* last one */ {""}
	};
	return simple_fill_super(sb, 0x6e667364, nfsd_files);
}

static int nfsd_get_sb(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *data, struct vfsmount *mnt)
{
	return get_sb_single(fs_type, flags, data, nfsd_fill_super, mnt);
}

static struct file_system_type nfsd_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "nfsd",
	.get_sb		= nfsd_get_sb,
	.kill_sb	= kill_litter_super,
};

static int __init init_nfsd(void)
{
	int retval;
	printk(KERN_INFO "Installing knfsd (copyright (C) 1996 [e-mail]).\n");

	retval = nfs4_state_init(); /* nfs4 locking state */
	if (retval)
		return retval;
	nfsd_stat_init();	/* Statistics */
	nfsd_cache_init();	/* RPC reply cache */
	nfsd_export_init();	/* Exports table */
	nfsd_lockd_init();	/* lockd->nfsd callbacks */
	nfsd_idmap_init();      /* Name to ID mapping */
	if (proc_mkdir("fs/nfs", NULL)) {
		struct proc_dir_entry *entry;
		entry = create_proc_entry("fs/nfs/exports", 0, NULL);
		if (entry)
			entry->proc_fops =  &exports_operations;
	}
	retval = register_filesystem(&nfsd_fs_type);
	if (retval) {
		nfsd_export_shutdown();
		nfsd_cache_shutdown();
		remove_proc_entry("fs/nfs/exports", NULL);
		remove_proc_entry("fs/nfs", NULL);
		nfsd_stat_shutdown();
		nfsd_lockd_shutdown();
	}
	return retval;
}

static void __exit exit_nfsd(void)
{
	nfsd_export_shutdown();
	nfsd_cache_shutdown();
	remove_proc_entry("fs/nfs/exports", NULL);
	remove_proc_entry("fs/nfs", NULL);
	nfsd_stat_shutdown();
	nfsd_lockd_shutdown();
	nfsd_idmap_shutdown();
	nfsd4_free_slabs();
	unregister_filesystem(&nfsd_fs_type);
}

MODULE_AUTHOR("Olaf Kirch <[e-mail]>");
MODULE_LICENSE("GPL");
module_init(init_nfsd)
module_exit(exit_nfsd)