diff options
Diffstat (limited to 'xenolinux-2.4.16-sparse/fs/nfs/nfsroot.c')
| -rw-r--r-- | xenolinux-2.4.16-sparse/fs/nfs/nfsroot.c | 466 |
1 files changed, 466 insertions, 0 deletions
diff --git a/xenolinux-2.4.16-sparse/fs/nfs/nfsroot.c b/xenolinux-2.4.16-sparse/fs/nfs/nfsroot.c new file mode 100644 index 0000000000..a2373467d5 --- /dev/null +++ b/xenolinux-2.4.16-sparse/fs/nfs/nfsroot.c @@ -0,0 +1,466 @@ +/* + * $Id: nfsroot.c,v 1.45 1998/03/07 10:44:46 mj Exp $ + * + * 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. + */ + +#include <linux/config.h> +#include <linux/types.h> +#include <linux/string.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/fs.h> +#include <linux/init.h> +#include <linux/sunrpc/clnt.h> +#include <linux/nfs.h> +#include <linux/nfs_fs.h> +#include <linux/nfs_mount.h> +#include <linux/in.h> +#include <linux/inet.h> +#include <linux/major.h> +#include <linux/utsname.h> +#include <net/ipconfig.h> + +/* Define this to allow debugging output */ +#undef NFSROOT_DEBUG +#define NFSDBG_FACILITY NFSDBG_ROOT + +/* 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_name[256] __initdata = ""; + +/* Address of NFS server */ +static __u32 servaddr __initdata = 0; + +/* Name of directory to mount */ +static char nfs_path[NFS_MAXPATHLEN] __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 + + ***************************************************************************/ + +/* + * The following integer options are recognized + */ +static struct nfs_int_opts { + char *name; + int *val; +} root_int_opts[] __initdata = { + { "port", &nfs_port }, + { "rsize", &nfs_data.rsize }, + { "wsize", &nfs_data.wsize }, + { "timeo", &nfs_data.timeo }, + { "retrans", &nfs_data.retrans }, + { "acregmin", &nfs_data.acregmin }, + { "acregmax", &nfs_data.acregmax }, + { "acdirmin", &nfs_data.acdirmin }, + { "acdirmax", &nfs_data.acdirmax }, + { NULL, NULL } +}; + + +/* + * And now the flag options + */ +static struct nfs_bool_opts { + char *name; + int and_mask; + int or_mask; +} root_bool_opts[] __initdata = { + { "soft", ~NFS_MOUNT_SOFT, NFS_MOUNT_SOFT }, + { "hard", ~NFS_MOUNT_SOFT, 0 }, + { "intr", ~NFS_MOUNT_INTR, NFS_MOUNT_INTR }, + { "nointr", ~NFS_MOUNT_INTR, 0 }, + { "posix", ~NFS_MOUNT_POSIX, NFS_MOUNT_POSIX }, + { "noposix", ~NFS_MOUNT_POSIX, 0 }, + { "cto", ~NFS_MOUNT_NOCTO, 0 }, + { "nocto", ~NFS_MOUNT_NOCTO, NFS_MOUNT_NOCTO }, + { "ac", ~NFS_MOUNT_NOAC, 0 }, + { "noac", ~NFS_MOUNT_NOAC, NFS_MOUNT_NOAC }, + { "lock", ~NFS_MOUNT_NONLM, 0 }, + { "nolock", ~NFS_MOUNT_NONLM, NFS_MOUNT_NONLM }, +#ifdef CONFIG_NFS_V3 + { "v2", ~NFS_MOUNT_VER3, 0 }, + { "v3", ~NFS_MOUNT_VER3, NFS_MOUNT_VER3 }, +#endif + { "udp", ~NFS_MOUNT_TCP, 0 }, + { "tcp", ~NFS_MOUNT_TCP, NFS_MOUNT_TCP }, + { "broken_suid",~NFS_MOUNT_BROKEN_SUID, NFS_MOUNT_BROKEN_SUID }, + { NULL, 0, 0 } +}; + + +/* + * Extract IP address from the parameter string if needed. Note that we + * need to have root_server_addr set _before_ IPConfig gets called as it + * can override it. + */ +static void __init root_nfs_parse_addr(char *name) +{ + int octets = 0; + char *cp, *cq; + + cp = cq = name; + while (octets < 4) { + while (*cp >= '0' && *cp <= '9') + cp++; + if (cp == cq || cp - cq > 3) + break; + if (*cp == '.' || octets == 3) + octets++; + if (octets < 4) + cp++; + cq = cp; + } + if (octets == 4 && (*cp == ':' || *cp == '\0')) { + if (*cp == ':') + *cp++ = '\0'; + root_server_addr = in_aton(name); + strcpy(name, cp); + } +} + + +/* + * Parse option string. + */ +static void __init root_nfs_parse(char *name, char *buf) +{ + char *options, *val, *cp; + + if ((options = strchr(name, ','))) { + *options++ = 0; + cp = strtok(options, ","); + while (cp) { + if ((val = strchr(cp, '='))) { + struct nfs_int_opts *opts = root_int_opts; + *val++ = '\0'; + while (opts->name && strcmp(opts->name, cp)) + opts++; + if (opts->name) + *(opts->val) = (int) simple_strtoul(val, NULL, 10); + } else { + struct nfs_bool_opts *opts = root_bool_opts; + while (opts->name && strcmp(opts->name, cp)) + opts++; + if (opts->name) { + nfs_data.flags &= opts->and_mask; + nfs_data.flags |= opts->or_mask; + } + } + cp = strtok(NULL, ","); + } + } + if (name[0] && strcmp(name, "default")) { + strncpy(buf, name, NFS_MAXPATHLEN-1); + buf[NFS_MAXPATHLEN-1] = 0; + } +} + + +/* + * Prepare the NFS data structure and parse all options. + */ +static int __init root_nfs_name(char *name) +{ + char buf[NFS_MAXPATHLEN]; + 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_BUFFER_SIZE; + nfs_data.wsize = NFS_DEF_FILE_IO_BUFFER_SIZE; + nfs_data.bsize = 0; + nfs_data.timeo = 7; + nfs_data.retrans = 3; + nfs_data.acregmin = 3; + nfs_data.acregmax = 60; + nfs_data.acdirmin = 30; + nfs_data.acdirmax = 60; + 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 = system_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_path, buf, cp); + + return 1; +} + + +/* + * Get NFS server address. + */ +static int __init root_nfs_addr(void) +{ + if ((servaddr = root_server_addr) == INADDR_NONE) { + printk(KERN_ERR "Root-NFS: No NFS server available, giving up.\n"); + return -1; + } + + strncpy(nfs_data.hostname, in_ntoa(servaddr), sizeof(nfs_data.hostname)-1); + 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_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 + + +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_name) < 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. + */ +int __init nfs_root_setup(char *line) +{ + ROOT_DEV = MKDEV(UNNAMED_MAJOR, 255); + if (line[0] == '/' || line[0] == ',' || (line[0] >= '0' && line[0] <= '9')) { + strncpy(nfs_root_name, line, sizeof(nfs_root_name)); + nfs_root_name[sizeof(nfs_root_name)-1] = '\0'; + } else { + int n = strlen(line) + strlen(NFS_ROOT); + if (n >= sizeof(nfs_root_name)) + line[sizeof(nfs_root_name) - strlen(NFS_ROOT) - 1] = '\0'; + sprintf(nfs_root_name, NFS_ROOT, line); + } + root_nfs_parse_addr(nfs_root_name); + 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, __u32 addr, __u16 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 %s\n", + program, version, in_ntoa(servaddr)); + set_sockaddr(&sin, servaddr, 0); + return rpc_getport_external(&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 = htons(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 = htons(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; + int status; + + set_sockaddr(&sin, servaddr, mount_port); + if (nfs_data.flags & NFS_MOUNT_VER3) + status = nfs3_mount(&sin, nfs_path, &nfs_data.root); + else + status = nfs_mount(&sin, nfs_path, &nfs_data.root); + if (status < 0) + printk(KERN_ERR "Root-NFS: Server returned error %d " + "while mounting %s\n", status, nfs_path); + + return status; +} + +/* + * Get the NFS port numbers and file handle, and return the prepared 'data' + * argument for ->read_super() 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, nfs_port); + return (void*)&nfs_data; +} |