[deliverable/linux.git] / fs / nfs / nfsroot.c

/*
 *  Copyright (C) 1995, 1996  Gero Kuhlmann <gero@gkminix.han.de>
 *
 *  Allow an NFS filesystem to be mounted as root. The way this works is:
 *     (1) Use the IP autoconfig mechanism to set local IP addresses and routes.
 *     (2) Handle RPC negotiation with the system which replied to RARP or
 *         was reported as a boot server by BOOTP or manually.
 *     (3) The actual mounting is done later, when init() is running.
 *
 *
 *	Changes:
 *
 *	Alan Cox	:	Removed get_address name clash with FPU.
 *	Alan Cox	:	Reformatted a bit.
 *	Gero Kuhlmann	:	Code cleanup
 *	Michael Rausch  :	Fixed recognition of an incoming RARP answer.
 *	Martin Mares	: (2.0)	Auto-configuration via BOOTP supported.
 *	Martin Mares	:	Manual selection of interface & BOOTP/RARP.
 *	Martin Mares	:	Using network routes instead of host routes,
 *				allowing the default configuration to be used
 *				for normal operation of the host.
 *	Martin Mares	:	Randomized timer with exponential backoff
 *				installed to minimize network congestion.
 *	Martin Mares	:	Code cleanup.
 *	Martin Mares	: (2.1)	BOOTP and RARP made configuration options.
 *	Martin Mares	:	Server hostname generation fixed.
 *	Gerd Knorr	:	Fixed wired inode handling
 *	Martin Mares	: (2.2)	"0.0.0.0" addresses from command line ignored.
 *	Martin Mares	:	RARP replies not tested for server address.
 *	Gero Kuhlmann	: (2.3) Some bug fixes and code cleanup again (please
 *				send me your new patches _before_ bothering
 *				Linus so that I don' always have to cleanup
 *				_afterwards_ - thanks)
 *	Gero Kuhlmann	:	Last changes of Martin Mares undone.
 *	Gero Kuhlmann	: 	RARP replies are tested for specified server
 *				again. However, it's now possible to have
 *				different RARP and NFS servers.
 *	Gero Kuhlmann	:	"0.0.0.0" addresses from command line are
 *				now mapped to INADDR_NONE.
 *	Gero Kuhlmann	:	Fixed a bug which prevented BOOTP path name
 *				from being used (thanks to Leo Spiekman)
 *	Andy Walker	:	Allow to specify the NFS server in nfs_root
 *				without giving a path name
 *	Swen Thümmler	:	Allow to specify the NFS options in nfs_root
 *				without giving a path name. Fix BOOTP request
 *				for domainname (domainname is NIS domain, not
 *				DNS domain!). Skip dummy devices for BOOTP.
 *	Jacek Zapala	:	Fixed a bug which prevented server-ip address
 *				from nfsroot parameter from being used.
 *	Olaf Kirch	:	Adapted to new NFS code.
 *	Jakub Jelinek	:	Free used code segment.
 *	Marko Kohtala	:	Fixed some bugs.
 *	Martin Mares	:	Debug message cleanup
 *	Martin Mares	:	Changed to use the new generic IP layer autoconfig
 *				code. BOOTP and RARP moved there.
 *	Martin Mares	:	Default path now contains host name instead of
 *				host IP address (but host name defaults to IP
 *				address anyway).
 *	Martin Mares	:	Use root_server_addr appropriately during setup.
 *	Martin Mares	:	Rewrote parameter parsing, now hopefully giving
 *				correct overriding.
 *	Trond Myklebust :	Add in preliminary support for NFSv3 and TCP.
 *				Fix bug in root_nfs_addr(). nfs_data.namlen
 *				is NOT for the length of the hostname.
 *	Hua Qin		:	Support for mounting root file system via
 *				NFS over TCP.
 *	Fabian Frederick:	Option parser rebuilt (using parser lib)
*/

#include <linux/types.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/time.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/xprtsock.h>
#include <linux/nfs.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_mount.h>
#include <linux/in.h>
#include <linux/major.h>
#include <linux/utsname.h>
#include <linux/inet.h>
#include <linux/root_dev.h>
#include <net/ipconfig.h>
#include <linux/parser.h>

#include "internal.h"

/* Define this to allow debugging output */
#undef NFSROOT_DEBUG
#define NFSDBG_FACILITY NFSDBG_ROOT

/* Default port to use if server is not running a portmapper */
#define NFS_MNT_PORT	627

/* Default path we try to mount. "%s" gets replaced by our IP address */
#define NFS_ROOT		"/tftpboot/%s"

/* Parameters passed from the kernel command line */
static char nfs_root_parms[256] __initdata = "";

/* Address of NFS server */
static __be32 servaddr __initdata = 0;

/* Name of directory to mount */
static char nfs_export_path[NFS_MAXPATHLEN + 1] __initdata = { 0, };

/* NFS-related data */
static struct nfs_mount_data nfs_data __initdata = { 0, };/* NFS mount info */
static int nfs_port __initdata = 0;		/* Port to connect to for NFS */
static int mount_port __initdata = 0;		/* Mount daemon port number */


/***************************************************************************

			     Parsing of options

 ***************************************************************************/

enum {
	/* Options that take integer arguments */
	Opt_port, Opt_rsize, Opt_wsize, Opt_timeo, Opt_retrans, Opt_acregmin,
	Opt_acregmax, Opt_acdirmin, Opt_acdirmax,
	/* Options that take no arguments */
	Opt_soft, Opt_hard, Opt_intr,
	Opt_nointr, Opt_posix, Opt_noposix, Opt_cto, Opt_nocto, Opt_ac, 
	Opt_noac, Opt_lock, Opt_nolock, Opt_v2, Opt_v3, Opt_udp, Opt_tcp,
	Opt_acl, Opt_noacl,
	/* Error token */
	Opt_err
};

static const match_table_t tokens __initconst = {
	{Opt_port, "port=%u"},
	{Opt_rsize, "rsize=%u"},
	{Opt_wsize, "wsize=%u"},
	{Opt_timeo, "timeo=%u"},
	{Opt_retrans, "retrans=%u"},
	{Opt_acregmin, "acregmin=%u"},
	{Opt_acregmax, "acregmax=%u"},
	{Opt_acdirmin, "acdirmin=%u"},
	{Opt_acdirmax, "acdirmax=%u"},
	{Opt_soft, "soft"},
	{Opt_hard, "hard"},
	{Opt_intr, "intr"},
	{Opt_nointr, "nointr"},
	{Opt_posix, "posix"},
	{Opt_noposix, "noposix"},
	{Opt_cto, "cto"},
	{Opt_nocto, "nocto"},
	{Opt_ac, "ac"},
	{Opt_noac, "noac"},
	{Opt_lock, "lock"},
	{Opt_nolock, "nolock"},
	{Opt_v2, "nfsvers=2"},
	{Opt_v2, "v2"},
	{Opt_v3, "nfsvers=3"},
	{Opt_v3, "v3"},
	{Opt_udp, "proto=udp"},
	{Opt_udp, "udp"},
	{Opt_tcp, "proto=tcp"},
	{Opt_tcp, "tcp"},
	{Opt_acl, "acl"},
	{Opt_noacl, "noacl"},
	{Opt_err, NULL}
	
};

/*
 *  Parse option string.
 */

static int __init root_nfs_parse(char *name, char *buf)
{

	char *p;
	substring_t args[MAX_OPT_ARGS];
	int option;

	if (!name)
		return 1;

	/* Set the NFS remote path */
	p = strsep(&name, ",");
	if (p[0] != '\0' && strcmp(p, "default") != 0)
		strlcpy(buf, p, NFS_MAXPATHLEN);

	while ((p = strsep (&name, ",")) != NULL) {
		int token; 
		if (!*p)
			continue;
		token = match_token(p, tokens, args);

		/* %u tokens only. Beware if you add new tokens! */
		if (token < Opt_soft && match_int(&args[0], &option))
			return 0;
		switch (token) {
			case Opt_port:
				nfs_port = option;
				break;
			case Opt_rsize:
				nfs_data.rsize = option;
				break;
			case Opt_wsize:
				nfs_data.wsize = option;
				break;
			case Opt_timeo:
				nfs_data.timeo = option;
				break;
			case Opt_retrans:
				nfs_data.retrans = option;
				break;
			case Opt_acregmin:
				nfs_data.acregmin = option;
				break;
			case Opt_acregmax:
				nfs_data.acregmax = option;
				break;
			case Opt_acdirmin:
				nfs_data.acdirmin = option;
				break;
			case Opt_acdirmax:
				nfs_data.acdirmax = option;
				break;
			case Opt_soft:
				nfs_data.flags |= NFS_MOUNT_SOFT;
				break;
			case Opt_hard:
				nfs_data.flags &= ~NFS_MOUNT_SOFT;
				break;
			case Opt_intr:
			case Opt_nointr:
				break;
			case Opt_posix:
				nfs_data.flags |= NFS_MOUNT_POSIX;
				break;
			case Opt_noposix:
				nfs_data.flags &= ~NFS_MOUNT_POSIX;
				break;
			case Opt_cto:
				nfs_data.flags &= ~NFS_MOUNT_NOCTO;
				break;
			case Opt_nocto:
				nfs_data.flags |= NFS_MOUNT_NOCTO;
				break;
			case Opt_ac:
				nfs_data.flags &= ~NFS_MOUNT_NOAC;
				break;
			case Opt_noac:
				nfs_data.flags |= NFS_MOUNT_NOAC;
				break;
			case Opt_lock:
				nfs_data.flags &= ~NFS_MOUNT_NONLM;
				break;
			case Opt_nolock:
				nfs_data.flags |= NFS_MOUNT_NONLM;
				break;
			case Opt_v2:
				nfs_data.flags &= ~NFS_MOUNT_VER3;
				break;
			case Opt_v3:
				nfs_data.flags |= NFS_MOUNT_VER3;
				break;
			case Opt_udp:
				nfs_data.flags &= ~NFS_MOUNT_TCP;
				break;
			case Opt_tcp:
				nfs_data.flags |= NFS_MOUNT_TCP;
				break;
			case Opt_acl:
				nfs_data.flags &= ~NFS_MOUNT_NOACL;
				break;
			case Opt_noacl:
				nfs_data.flags |= NFS_MOUNT_NOACL;
				break;
			default:
				printk(KERN_WARNING "Root-NFS: unknown "
					"option: %s\n", p);
				return 0;
		}
	}

	return 1;
}

/*
 *  Prepare the NFS data structure and parse all options.
 */
static int __init root_nfs_name(char *name)
{
	static char buf[NFS_MAXPATHLEN] __initdata;
	char *cp;

	/* Set some default values */
	memset(&nfs_data, 0, sizeof(nfs_data));
	nfs_port          = -1;
	nfs_data.version  = NFS_MOUNT_VERSION;
	nfs_data.flags    = NFS_MOUNT_NONLM;	/* No lockd in nfs root yet */
	nfs_data.rsize    = NFS_DEF_FILE_IO_SIZE;
	nfs_data.wsize    = NFS_DEF_FILE_IO_SIZE;
	nfs_data.acregmin = NFS_DEF_ACREGMIN;
	nfs_data.acregmax = NFS_DEF_ACREGMAX;
	nfs_data.acdirmin = NFS_DEF_ACDIRMIN;
	nfs_data.acdirmax = NFS_DEF_ACDIRMAX;
	strcpy(buf, NFS_ROOT);

	/* Process options received from the remote server */
	root_nfs_parse(root_server_path, buf);

	/* Override them by options set on kernel command-line */
	root_nfs_parse(name, buf);

	cp = utsname()->nodename;
	if (strlen(buf) + strlen(cp) > NFS_MAXPATHLEN) {
		printk(KERN_ERR "Root-NFS: Pathname for remote directory too long.\n");
		return -1;
	}
	sprintf(nfs_export_path, buf, cp);

	return 1;
}


/*
 *  Get NFS server address.
 */
static int __init root_nfs_addr(void)
{
	if ((servaddr = root_server_addr) == htonl(INADDR_NONE)) {
		printk(KERN_ERR "Root-NFS: No NFS server available, giving up.\n");
		return -1;
	}

	snprintf(nfs_data.hostname, sizeof(nfs_data.hostname),
		 "%pI4", &servaddr);
	return 0;
}

/*
 *  Tell the user what's going on.
 */
#ifdef NFSROOT_DEBUG
static void __init root_nfs_print(void)
{
	printk(KERN_NOTICE "Root-NFS: Mounting %s on server %s as root\n",
		nfs_export_path, nfs_data.hostname);
	printk(KERN_NOTICE "Root-NFS:     rsize = %d, wsize = %d, timeo = %d, retrans = %d\n",
		nfs_data.rsize, nfs_data.wsize, nfs_data.timeo, nfs_data.retrans);
	printk(KERN_NOTICE "Root-NFS:     acreg (min,max) = (%d,%d), acdir (min,max) = (%d,%d)\n",
		nfs_data.acregmin, nfs_data.acregmax,
		nfs_data.acdirmin, nfs_data.acdirmax);
	printk(KERN_NOTICE "Root-NFS:     nfsd port = %d, mountd port = %d, flags = %08x\n",
		nfs_port, mount_port, nfs_data.flags);
}
#endif


static int __init root_nfs_init(void)
{
#ifdef NFSROOT_DEBUG
	nfs_debug |= NFSDBG_ROOT;
#endif

	/*
	 * Decode the root directory path name and NFS options from
	 * the kernel command line. This has to go here in order to
	 * be able to use the client IP address for the remote root
	 * directory (necessary for pure RARP booting).
	 */
	if (root_nfs_name(nfs_root_parms) < 0 ||
	    root_nfs_addr() < 0)
		return -1;

#ifdef NFSROOT_DEBUG
	root_nfs_print();
#endif

	return 0;
}

/*
 *  Parse NFS server and directory information passed on the kernel
 *  command line.
 *
 *  nfsroot=[<server-ip>:]<root-dir>[,<nfs-options>]
 *
 *  If there is a "%s" token in the <root-dir> string, it is replaced
 *  by the ASCII-representation of the client's IP address.
 */
static int __init nfs_root_setup(char *line)
{
	ROOT_DEV = Root_NFS;

	if (line[0] == '/' || line[0] == ',' || (line[0] >= '0' && line[0] <= '9')) {
		strlcpy(nfs_root_parms, line, sizeof(nfs_root_parms));
	} else {
		size_t n = strlen(line) + sizeof(NFS_ROOT) - 1;
		if (n >= sizeof(nfs_root_parms))
			line[sizeof(nfs_root_parms) - sizeof(NFS_ROOT) - 2] = '\0';
		sprintf(nfs_root_parms, NFS_ROOT, line);
	}

	/*
	 * Extract the IP address of the NFS server containing our
	 * root file system, if one was specified.
	 *
	 * Note: root_nfs_parse_addr() removes the server-ip from
	 *	 nfs_root_parms, if it exists.
	 */
	root_server_addr = root_nfs_parse_addr(nfs_root_parms);

	return 1;
}

__setup("nfsroot=", nfs_root_setup);

/***************************************************************************

	       Routines to actually mount the root directory

 ***************************************************************************/

/*
 *  Construct sockaddr_in from address and port number.
 */
static inline void
set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
{
	sin->sin_family = AF_INET;
	sin->sin_addr.s_addr = addr;
	sin->sin_port = port;
}

/*
 *  Query server portmapper for the port of a daemon program.
 */
static int __init root_nfs_getport(int program, int version, int proto)
{
	struct sockaddr_in sin;

	printk(KERN_NOTICE "Looking up port of RPC %d/%d on %pI4\n",
		program, version, &servaddr);
	set_sockaddr(&sin, servaddr, 0);
	return rpcb_getport_sync(&sin, program, version, proto);
}


/*
 *  Use portmapper to find mountd and nfsd port numbers if not overriden
 *  by the user. Use defaults if portmapper is not available.
 *  XXX: Is there any nfs server with no portmapper?
 */
static int __init root_nfs_ports(void)
{
	int port;
	int nfsd_ver, mountd_ver;
	int nfsd_port, mountd_port;
	int proto;

	if (nfs_data.flags & NFS_MOUNT_VER3) {
		nfsd_ver = NFS3_VERSION;
		mountd_ver = NFS_MNT3_VERSION;
		nfsd_port = NFS_PORT;
		mountd_port = NFS_MNT_PORT;
	} else {
		nfsd_ver = NFS2_VERSION;
		mountd_ver = NFS_MNT_VERSION;
		nfsd_port = NFS_PORT;
		mountd_port = NFS_MNT_PORT;
	}

	proto = (nfs_data.flags & NFS_MOUNT_TCP) ? IPPROTO_TCP : IPPROTO_UDP;

	if (nfs_port < 0) {
		if ((port = root_nfs_getport(NFS_PROGRAM, nfsd_ver, proto)) < 0) {
			printk(KERN_ERR "Root-NFS: Unable to get nfsd port "
					"number from server, using default\n");
			port = nfsd_port;
		}
		nfs_port = port;
		dprintk("Root-NFS: Portmapper on server returned %d "
			"as nfsd port\n", port);
	}

	if ((port = root_nfs_getport(NFS_MNT_PROGRAM, mountd_ver, proto)) < 0) {
		printk(KERN_ERR "Root-NFS: Unable to get mountd port "
				"number from server, using default\n");
		port = mountd_port;
	}
	mount_port = port;
	dprintk("Root-NFS: mountd port is %d\n", port);

	return 0;
}


/*
 *  Get a file handle from the server for the directory which is to be
 *  mounted.
 */
static int __init root_nfs_get_handle(void)
{
	struct sockaddr_in sin;
	unsigned int auth_flav_len = 0;
	struct nfs_mount_request request = {
		.sap		= (struct sockaddr *)&sin,
		.salen		= sizeof(sin),
		.dirpath	= nfs_export_path,
		.version	= (nfs_data.flags & NFS_MOUNT_VER3) ?
					NFS_MNT3_VERSION : NFS_MNT_VERSION,
		.protocol	= (nfs_data.flags & NFS_MOUNT_TCP) ?
					XPRT_TRANSPORT_TCP : XPRT_TRANSPORT_UDP,
		.auth_flav_len	= &auth_flav_len,
	};
	int status = -ENOMEM;

	request.fh = nfs_alloc_fhandle();
	if (!request.fh)
		goto out;
	set_sockaddr(&sin, servaddr, htons(mount_port));
	status = nfs_mount(&request);
	if (status < 0)
		printk(KERN_ERR "Root-NFS: Server returned error %d "
				"while mounting %s\n", status, nfs_export_path);
	else {
		nfs_data.root.size = request.fh->size;
		memcpy(&nfs_data.root.data, request.fh->data, request.fh->size);
	}
	nfs_free_fhandle(request.fh);
out:
	return status;
}

/*
 *  Get the NFS port numbers and file handle, and return the prepared 'data'
 *  argument for mount() if everything went OK. Return NULL otherwise.
 */
void * __init nfs_root_data(void)
{
	if (root_nfs_init() < 0
	 || root_nfs_ports() < 0
	 || root_nfs_get_handle() < 0)
		return NULL;
	set_sockaddr((struct sockaddr_in *) &nfs_data.addr, servaddr, htons(nfs_port));
	return (void*)&nfs_data;
}
Commit	Line	Data
1da177e4	1	/*
1da177e4 LT	2	* Copyright (C) 1995, 1996 Gero Kuhlmann <gero@gkminix.han.de>
	3	*
	4	* Allow an NFS filesystem to be mounted as root. The way this works is:
	5	* (1) Use the IP autoconfig mechanism to set local IP addresses and routes.
	6	* (2) Handle RPC negotiation with the system which replied to RARP or
	7	* was reported as a boot server by BOOTP or manually.
	8	* (3) The actual mounting is done later, when init() is running.
	9	*
	10	*
	11	* Changes:
	12	*
	13	* Alan Cox : Removed get_address name clash with FPU.
	14	* Alan Cox : Reformatted a bit.
	15	* Gero Kuhlmann : Code cleanup
	16	* Michael Rausch : Fixed recognition of an incoming RARP answer.
	17	* Martin Mares : (2.0) Auto-configuration via BOOTP supported.
	18	* Martin Mares : Manual selection of interface & BOOTP/RARP.
	19	* Martin Mares : Using network routes instead of host routes,
	20	* allowing the default configuration to be used
	21	* for normal operation of the host.
	22	* Martin Mares : Randomized timer with exponential backoff
	23	* installed to minimize network congestion.
	24	* Martin Mares : Code cleanup.
	25	* Martin Mares : (2.1) BOOTP and RARP made configuration options.
	26	* Martin Mares : Server hostname generation fixed.
	27	* Gerd Knorr : Fixed wired inode handling
	28	* Martin Mares : (2.2) "0.0.0.0" addresses from command line ignored.
	29	* Martin Mares : RARP replies not tested for server address.
	30	* Gero Kuhlmann : (2.3) Some bug fixes and code cleanup again (please
	31	* send me your new patches _before_ bothering
	32	* Linus so that I don' always have to cleanup
	33	* _afterwards_ - thanks)
	34	* Gero Kuhlmann : Last changes of Martin Mares undone.
	35	* Gero Kuhlmann : RARP replies are tested for specified server
	36	* again. However, it's now possible to have
	37	* different RARP and NFS servers.
	38	* Gero Kuhlmann : "0.0.0.0" addresses from command line are
	39	* now mapped to INADDR_NONE.
	40	* Gero Kuhlmann : Fixed a bug which prevented BOOTP path name
	41	* from being used (thanks to Leo Spiekman)
	42	* Andy Walker : Allow to specify the NFS server in nfs_root
	43	* without giving a path name
96de0e25	44	* Swen Thümmler : Allow to specify the NFS options in nfs_root
1da177e4 LT	45	* without giving a path name. Fix BOOTP request
	46	* for domainname (domainname is NIS domain, not
	47	* DNS domain!). Skip dummy devices for BOOTP.
	48	* Jacek Zapala : Fixed a bug which prevented server-ip address
	49	* from nfsroot parameter from being used.
	50	* Olaf Kirch : Adapted to new NFS code.
	51	* Jakub Jelinek : Free used code segment.
	52	* Marko Kohtala : Fixed some bugs.
	53	* Martin Mares : Debug message cleanup
	54	* Martin Mares : Changed to use the new generic IP layer autoconfig
	55	* code. BOOTP and RARP moved there.
	56	* Martin Mares : Default path now contains host name instead of
	57	* host IP address (but host name defaults to IP
	58	* address anyway).
	59	* Martin Mares : Use root_server_addr appropriately during setup.
	60	* Martin Mares : Rewrote parameter parsing, now hopefully giving
	61	* correct overriding.
	62	* Trond Myklebust : Add in preliminary support for NFSv3 and TCP.
	63	* Fix bug in root_nfs_addr(). nfs_data.namlen
	64	* is NOT for the length of the hostname.
	65	* Hua Qin : Support for mounting root file system via
	66	* NFS over TCP.
	67	* Fabian Frederick: Option parser rebuilt (using parser lib)
	68	*/
	69
1da177e4 LT	70	#include <linux/types.h>
	71	#include <linux/string.h>
	72	#include <linux/kernel.h>
	73	#include <linux/time.h>
	74	#include <linux/fs.h>
	75	#include <linux/init.h>
	76	#include <linux/sunrpc/clnt.h>
0896a725	77	#include <linux/sunrpc/xprtsock.h>
1da177e4 LT	78	#include <linux/nfs.h>
	79	#include <linux/nfs_fs.h>
	80	#include <linux/nfs_mount.h>
	81	#include <linux/in.h>
	82	#include <linux/major.h>
	83	#include <linux/utsname.h>
	84	#include <linux/inet.h>
	85	#include <linux/root_dev.h>
	86	#include <net/ipconfig.h>
	87	#include <linux/parser.h>
	88
146ec944 CL	89	#include "internal.h"
146ec944 CL	90
1da177e4 LT	91	/* Define this to allow debugging output */
	92	#undef NFSROOT_DEBUG
	93	#define NFSDBG_FACILITY NFSDBG_ROOT
	94
2ad78097 CL	95	/* Default port to use if server is not running a portmapper */
	96	#define NFS_MNT_PORT 627
	97
1da177e4 LT	98	/* Default path we try to mount. "%s" gets replaced by our IP address */
	99	#define NFS_ROOT "/tftpboot/%s"
	100
	101	/* Parameters passed from the kernel command line */
60ac0368	102	static char nfs_root_parms[256] __initdata = "";
1da177e4 LT	103
1da177e4 LT	104	/* Address of NFS server */
5a874db4	105	static __be32 servaddr __initdata = 0;
1da177e4 LT	106
1da177e4 LT	107	/* Name of directory to mount */
674b2222	108	static char nfs_export_path[NFS_MAXPATHLEN + 1] __initdata = { 0, };
1da177e4 LT	109
	110	/* NFS-related data */
	111	static struct nfs_mount_data nfs_data __initdata = { 0, };/* NFS mount info */
	112	static int nfs_port __initdata = 0; /* Port to connect to for NFS */
	113	static int mount_port __initdata = 0; /* Mount daemon port number */
	114
	115
	116	/***************************************************************************
	117
	118	Parsing of options
	119
	120	***************************************************************************/
	121
	122	enum {
	123	/* Options that take integer arguments */
	124	Opt_port, Opt_rsize, Opt_wsize, Opt_timeo, Opt_retrans, Opt_acregmin,
	125	Opt_acregmax, Opt_acdirmin, Opt_acdirmax,
	126	/* Options that take no arguments */
	127	Opt_soft, Opt_hard, Opt_intr,
	128	Opt_nointr, Opt_posix, Opt_noposix, Opt_cto, Opt_nocto, Opt_ac,
	129	Opt_noac, Opt_lock, Opt_nolock, Opt_v2, Opt_v3, Opt_udp, Opt_tcp,
b7fa0554	130	Opt_acl, Opt_noacl,
1da177e4 LT	131	/* Error token */
	132	Opt_err
	133	};
	134
d0367a50	135	static const match_table_t tokens __initconst = {
1da177e4 LT	136	{Opt_port, "port=%u"},
	137	{Opt_rsize, "rsize=%u"},
	138	{Opt_wsize, "wsize=%u"},
	139	{Opt_timeo, "timeo=%u"},
	140	{Opt_retrans, "retrans=%u"},
	141	{Opt_acregmin, "acregmin=%u"},
	142	{Opt_acregmax, "acregmax=%u"},
	143	{Opt_acdirmin, "acdirmin=%u"},
	144	{Opt_acdirmax, "acdirmax=%u"},
	145	{Opt_soft, "soft"},
	146	{Opt_hard, "hard"},
	147	{Opt_intr, "intr"},
	148	{Opt_nointr, "nointr"},
	149	{Opt_posix, "posix"},
	150	{Opt_noposix, "noposix"},
	151	{Opt_cto, "cto"},
	152	{Opt_nocto, "nocto"},
	153	{Opt_ac, "ac"},
	154	{Opt_noac, "noac"},
	155	{Opt_lock, "lock"},
	156	{Opt_nolock, "nolock"},
	157	{Opt_v2, "nfsvers=2"},
	158	{Opt_v2, "v2"},
	159	{Opt_v3, "nfsvers=3"},
	160	{Opt_v3, "v3"},
	161	{Opt_udp, "proto=udp"},
	162	{Opt_udp, "udp"},
	163	{Opt_tcp, "proto=tcp"},
	164	{Opt_tcp, "tcp"},
b7fa0554 AG	165	{Opt_acl, "acl"},
b7fa0554 AG	166	{Opt_noacl, "noacl"},
1da177e4 LT	167	{Opt_err, NULL}
	168
	169	};
	170
	171	/*
	172	* Parse option string.
	173	*/
	174
	175	static int __init root_nfs_parse(char name, char buf)
	176	{
	177
	178	char *p;
	179	substring_t args[MAX_OPT_ARGS];
	180	int option;
	181
	182	if (!name)
	183	return 1;
	184
	185	/* Set the NFS remote path */
	186	p = strsep(&name, ",");
	187	if (p[0] != '\0' && strcmp(p, "default") != 0)
	188	strlcpy(buf, p, NFS_MAXPATHLEN);
	189
	190	while ((p = strsep (&name, ",")) != NULL) {
	191	int token;
	192	if (!*p)
	193	continue;
	194	token = match_token(p, tokens, args);
	195
	196	/* %u tokens only. Beware if you add new tokens! */
	197	if (token < Opt_soft && match_int(&args[0], &option))
	198	return 0;
	199	switch (token) {
	200	case Opt_port:
	201	nfs_port = option;
	202	break;
	203	case Opt_rsize:
	204	nfs_data.rsize = option;
	205	break;
	206	case Opt_wsize:
	207	nfs_data.wsize = option;
	208	break;
	209	case Opt_timeo:
	210	nfs_data.timeo = option;
	211	break;
	212	case Opt_retrans:
	213	nfs_data.retrans = option;
	214	break;
	215	case Opt_acregmin:
	216	nfs_data.acregmin = option;
	217	break;
	218	case Opt_acregmax:
	219	nfs_data.acregmax = option;
	220	break;
	221	case Opt_acdirmin:
	222	nfs_data.acdirmin = option;
	223	break;
	224	case Opt_acdirmax:
	225	nfs_data.acdirmax = option;
	226	break;
	227	case Opt_soft:
	228	nfs_data.flags \|= NFS_MOUNT_SOFT;
	229	break;
	230	case Opt_hard:
231	nfs_data.flags &= ~NFS_MOUNT_SOFT;
232	break;
233	case Opt_intr:
1da177e4	234	case Opt_nointr:
1da177e4 LT	235	break;
	236	case Opt_posix:
	237	nfs_data.flags \|= NFS_MOUNT_POSIX;
	238	break;
	239	case Opt_noposix:
	240	nfs_data.flags &= ~NFS_MOUNT_POSIX;
	241	break;
	242	case Opt_cto:
	243	nfs_data.flags &= ~NFS_MOUNT_NOCTO;
	244	break;
	245	case Opt_nocto:
	246	nfs_data.flags \|= NFS_MOUNT_NOCTO;
	247	break;
	248	case Opt_ac:
	249	nfs_data.flags &= ~NFS_MOUNT_NOAC;
	250	break;
	251	case Opt_noac:
	252	nfs_data.flags \|= NFS_MOUNT_NOAC;
	253	break;
	254	case Opt_lock:
	255	nfs_data.flags &= ~NFS_MOUNT_NONLM;
	256	break;
	257	case Opt_nolock:
	258	nfs_data.flags \|= NFS_MOUNT_NONLM;
	259	break;
	260	case Opt_v2:
	261	nfs_data.flags &= ~NFS_MOUNT_VER3;
	262	break;
	263	case Opt_v3:
	264	nfs_data.flags \|= NFS_MOUNT_VER3;
	265	break;
	266	case Opt_udp:
	267	nfs_data.flags &= ~NFS_MOUNT_TCP;
	268	break;
	269	case Opt_tcp:
	270	nfs_data.flags \|= NFS_MOUNT_TCP;
	271	break;
b7fa0554 AG	272	case Opt_acl:
	273	nfs_data.flags &= ~NFS_MOUNT_NOACL;
	274	break;
	275	case Opt_noacl:
	276	nfs_data.flags \|= NFS_MOUNT_NOACL;
	277	break;
21b6bf14 JD	278	default:
	279	printk(KERN_WARNING "Root-NFS: unknown "
	280	"option: %s\n", p);
1da177e4 LT	281	return 0;
	282	}
	283	}
	284
	285	return 1;
	286	}
	287
	288	/*
	289	* Prepare the NFS data structure and parse all options.
	290	*/
	291	static int __init root_nfs_name(char *name)
	292	{
	293	static char buf[NFS_MAXPATHLEN] __initdata;
	294	char *cp;
	295
	296	/* Set some default values */
	297	memset(&nfs_data, 0, sizeof(nfs_data));
	298	nfs_port = -1;
	299	nfs_data.version = NFS_MOUNT_VERSION;
	300	nfs_data.flags = NFS_MOUNT_NONLM; /* No lockd in nfs root yet */
40859d7e CL	301	nfs_data.rsize = NFS_DEF_FILE_IO_SIZE;
40859d7e CL	302	nfs_data.wsize = NFS_DEF_FILE_IO_SIZE;
0e0cab74 CL	303	nfs_data.acregmin = NFS_DEF_ACREGMIN;
	304	nfs_data.acregmax = NFS_DEF_ACREGMAX;
	305	nfs_data.acdirmin = NFS_DEF_ACDIRMIN;
	306	nfs_data.acdirmax = NFS_DEF_ACDIRMAX;
1da177e4 LT	307	strcpy(buf, NFS_ROOT);
	308
	309	/* Process options received from the remote server */
	310	root_nfs_parse(root_server_path, buf);
	311
	312	/* Override them by options set on kernel command-line */
	313	root_nfs_parse(name, buf);
	314
e9ff3990	315	cp = utsname()->nodename;
1da177e4 LT	316	if (strlen(buf) + strlen(cp) > NFS_MAXPATHLEN) {
	317	printk(KERN_ERR "Root-NFS: Pathname for remote directory too long.\n");
	318	return -1;
	319	}
7b5d2b98	320	sprintf(nfs_export_path, buf, cp);
1da177e4 LT	321
	322	return 1;
	323	}
	324
	325
	326	/*
	327	* Get NFS server address.
	328	*/
	329	static int __init root_nfs_addr(void)
	330	{
5a874db4	331	if ((servaddr = root_server_addr) == htonl(INADDR_NONE)) {
1da177e4 LT	332	printk(KERN_ERR "Root-NFS: No NFS server available, giving up.\n");
	333	return -1;
	334	}
	335
	336	snprintf(nfs_data.hostname, sizeof(nfs_data.hostname),
be859405	337	"%pI4", &servaddr);
1da177e4 LT	338	return 0;
	339	}
	340
	341	/*
	342	* Tell the user what's going on.
	343	*/
	344	#ifdef NFSROOT_DEBUG
	345	static void __init root_nfs_print(void)
	346	{
	347	printk(KERN_NOTICE "Root-NFS: Mounting %s on server %s as root\n",
7b5d2b98	348	nfs_export_path, nfs_data.hostname);
1da177e4 LT	349	printk(KERN_NOTICE "Root-NFS: rsize = %d, wsize = %d, timeo = %d, retrans = %d\n",
	350	nfs_data.rsize, nfs_data.wsize, nfs_data.timeo, nfs_data.retrans);
	351	printk(KERN_NOTICE "Root-NFS: acreg (min,max) = (%d,%d), acdir (min,max) = (%d,%d)\n",
	352	nfs_data.acregmin, nfs_data.acregmax,
	353	nfs_data.acdirmin, nfs_data.acdirmax);
	354	printk(KERN_NOTICE "Root-NFS: nfsd port = %d, mountd port = %d, flags = %08x\n",
	355	nfs_port, mount_port, nfs_data.flags);
	356	}
	357	#endif
	358
	359
	360	static int __init root_nfs_init(void)
	361	{
	362	#ifdef NFSROOT_DEBUG
	363	nfs_debug \|= NFSDBG_ROOT;
	364	#endif
	365
	366	/*
	367	* Decode the root directory path name and NFS options from
	368	* the kernel command line. This has to go here in order to
	369	* be able to use the client IP address for the remote root
	370	* directory (necessary for pure RARP booting).
	371	*/
60ac0368	372	if (root_nfs_name(nfs_root_parms) < 0 \|\|
1da177e4 LT	373	root_nfs_addr() < 0)
	374	return -1;
	375
	376	#ifdef NFSROOT_DEBUG
	377	root_nfs_print();
	378	#endif
	379
	380	return 0;
	381	}
	382
1da177e4 LT	383	/*
	384	* Parse NFS server and directory information passed on the kernel
	385	* command line.
60ac0368 CL	386	*
	387	* nfsroot=[<server-ip>:]<root-dir>[,<nfs-options>]
	388	*
	389	* If there is a "%s" token in the <root-dir> string, it is replaced
	390	* by the ASCII-representation of the client's IP address.
1da177e4 LT	391	*/
	392	static int __init nfs_root_setup(char *line)
	393	{
	394	ROOT_DEV = Root_NFS;
60ac0368	395
1da177e4	396	if (line[0] == '/' \|\| line[0] == ',' \|\| (line[0] >= '0' && line[0] <= '9')) {
60ac0368	397	strlcpy(nfs_root_parms, line, sizeof(nfs_root_parms));
1da177e4	398	} else {
60ac0368 CL	399	size_t n = strlen(line) + sizeof(NFS_ROOT) - 1;
	400	if (n >= sizeof(nfs_root_parms))
	401	line[sizeof(nfs_root_parms) - sizeof(NFS_ROOT) - 2] = '\0';
	402	sprintf(nfs_root_parms, NFS_ROOT, line);
1da177e4	403	}
60ac0368 CL	404
	405	/*
	406	* Extract the IP address of the NFS server containing our
	407	* root file system, if one was specified.
	408	*
	409	* Note: root_nfs_parse_addr() removes the server-ip from
	410	* nfs_root_parms, if it exists.
	411	*/
	412	root_server_addr = root_nfs_parse_addr(nfs_root_parms);
	413
1da177e4 LT	414	return 1;
	415	}
	416
	417	__setup("nfsroot=", nfs_root_setup);
	418
	419	/***************************************************************************
	420
	421	Routines to actually mount the root directory
	422
	423	***************************************************************************/
	424
	425	/*
	426	* Construct sockaddr_in from address and port number.
	427	*/
	428	static inline void
5a874db4	429	set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
1da177e4 LT	430	{
	431	sin->sin_family = AF_INET;
	432	sin->sin_addr.s_addr = addr;
	433	sin->sin_port = port;
	434	}
	435
	436	/*
	437	* Query server portmapper for the port of a daemon program.
	438	*/
	439	static int __init root_nfs_getport(int program, int version, int proto)
	440	{
	441	struct sockaddr_in sin;
	442
be859405 HH	443	printk(KERN_NOTICE "Looking up port of RPC %d/%d on %pI4\n",
be859405 HH	444	program, version, &servaddr);
1da177e4	445	set_sockaddr(&sin, servaddr, 0);
cce63cd6	446	return rpcb_getport_sync(&sin, program, version, proto);
1da177e4 LT	447	}
	448
	449
	450	/*
	451	* Use portmapper to find mountd and nfsd port numbers if not overriden
	452	* by the user. Use defaults if portmapper is not available.
	453	* XXX: Is there any nfs server with no portmapper?
	454	*/
	455	static int __init root_nfs_ports(void)
	456	{
	457	int port;
	458	int nfsd_ver, mountd_ver;
	459	int nfsd_port, mountd_port;
	460	int proto;
	461
	462	if (nfs_data.flags & NFS_MOUNT_VER3) {
	463	nfsd_ver = NFS3_VERSION;
	464	mountd_ver = NFS_MNT3_VERSION;
	465	nfsd_port = NFS_PORT;
	466	mountd_port = NFS_MNT_PORT;
	467	} else {
	468	nfsd_ver = NFS2_VERSION;
	469	mountd_ver = NFS_MNT_VERSION;
	470	nfsd_port = NFS_PORT;
	471	mountd_port = NFS_MNT_PORT;
	472	}
	473
	474	proto = (nfs_data.flags & NFS_MOUNT_TCP) ? IPPROTO_TCP : IPPROTO_UDP;
	475
	476	if (nfs_port < 0) {
	477	if ((port = root_nfs_getport(NFS_PROGRAM, nfsd_ver, proto)) < 0) {
	478	printk(KERN_ERR "Root-NFS: Unable to get nfsd port "
	479	"number from server, using default\n");
	480	port = nfsd_port;
	481	}
8854eddb	482	nfs_port = port;
1da177e4 LT	483	dprintk("Root-NFS: Portmapper on server returned %d "
	484	"as nfsd port\n", port);
	485	}
	486
	487	if ((port = root_nfs_getport(NFS_MNT_PROGRAM, mountd_ver, proto)) < 0) {
	488	printk(KERN_ERR "Root-NFS: Unable to get mountd port "
	489	"number from server, using default\n");
	490	port = mountd_port;
	491	}
5a874db4	492	mount_port = port;
1da177e4 LT	493	dprintk("Root-NFS: mountd port is %d\n", port);
	494
	495	return 0;
	496	}
	497
	498
	499	/*
	500	* Get a file handle from the server for the directory which is to be
	501	* mounted.
	502	*/
	503	static int __init root_nfs_get_handle(void)
	504	{
1da177e4	505	struct sockaddr_in sin;
8e02f6b9	506	unsigned int auth_flav_len = 0;
c5d120f8 CL	507	struct nfs_mount_request request = {
	508	.sap = (struct sockaddr *)&sin,
	509	.salen = sizeof(sin),
	510	.dirpath = nfs_export_path,
	511	.version = (nfs_data.flags & NFS_MOUNT_VER3) ?
	512	NFS_MNT3_VERSION : NFS_MNT_VERSION,
	513	.protocol = (nfs_data.flags & NFS_MOUNT_TCP) ?
	514	XPRT_TRANSPORT_TCP : XPRT_TRANSPORT_UDP,
8e02f6b9	515	.auth_flav_len = &auth_flav_len,
c5d120f8	516	};
1b4c6065	517	int status = -ENOMEM;
1da177e4	518
1b4c6065 TM	519	request.fh = nfs_alloc_fhandle();
	520	if (!request.fh)
	521	goto out;
5a874db4	522	set_sockaddr(&sin, servaddr, htons(mount_port));
c5d120f8	523	status = nfs_mount(&request);
1da177e4 LT	524	if (status < 0)
1da177e4 LT	525	printk(KERN_ERR "Root-NFS: Server returned error %d "
7b5d2b98	526	"while mounting %s\n", status, nfs_export_path);
1da177e4	527	else {
1b4c6065 TM	528	nfs_data.root.size = request.fh->size;
1b4c6065 TM	529	memcpy(&nfs_data.root.data, request.fh->data, request.fh->size);
1da177e4	530	}
1b4c6065 TM	531	nfs_free_fhandle(request.fh);
1b4c6065 TM	532	out:
1da177e4 LT	533	return status;
	534	}
	535
	536	/*
	537	* Get the NFS port numbers and file handle, and return the prepared 'data'
	538	* argument for mount() if everything went OK. Return NULL otherwise.
	539	*/
	540	void * __init nfs_root_data(void)
	541	{
	542	if (root_nfs_init() < 0
	543	\|\| root_nfs_ports() < 0
	544	\|\| root_nfs_get_handle() < 0)
	545	return NULL;
5a874db4	546	set_sockaddr((struct sockaddr_in *) &nfs_data.addr, servaddr, htons(nfs_port));
1da177e4 LT	547	return (void*)&nfs_data;
1da177e4 LT	548	}