diff options
Diffstat (limited to 'fs/nfs/nfsroot.c')
-rw-r--r-- | fs/nfs/nfsroot.c | 566 |
1 files changed, 170 insertions, 396 deletions
diff --git a/fs/nfs/nfsroot.c b/fs/nfs/nfsroot.c index df101d9f546a..460df3652889 100644 --- a/fs/nfs/nfsroot.c +++ b/fs/nfs/nfsroot.c @@ -3,9 +3,10 @@ * * 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. + * (2) Construct the device string and the options string using DHCP + * option 17 and/or kernel command line options. + * (3) When mount_root() sets up the root file system, pass these strings + * to the NFS client's regular mount interface via sys_mount(). * * * Changes: @@ -65,470 +66,243 @@ * Hua Qin : Support for mounting root file system via * NFS over TCP. * Fabian Frederick: Option parser rebuilt (using parser lib) -*/ + * Chuck Lever : Use super.c's text-based mount option parsing + * Chuck Lever : Add "nfsrootdebug". + */ #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_name[256] __initdata = ""; +static char nfs_root_parms[256] __initdata = ""; + +/* Text-based mount options passed to super.c */ +static char nfs_root_options[256] __initdata = ""; /* Address of NFS server */ -static __be32 servaddr __initdata = 0; +static __be32 servaddr __initdata = htonl(INADDR_NONE); /* 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} - -}; +static char nfs_export_path[NFS_MAXPATHLEN + 1] __initdata = ""; + +/* server:export path string passed to super.c */ +static char nfs_root_device[NFS_MAXPATHLEN + 1] __initdata = ""; /* - * Parse option string. + * When the "nfsrootdebug" kernel command line option is specified, + * enable debugging messages for NFSROOT. */ - -static int __init root_nfs_parse(char *name, char *buf) +static int __init nfs_root_debug(char *__unused) { - - 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; - } - } - + nfs_debug |= NFSDBG_ROOT | NFSDBG_MOUNT; return 1; } +__setup("nfsrootdebug", nfs_root_debug); + /* - * Prepare the NFS data structure and parse all options. + * 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 root_nfs_name(char *name) +static int __init nfs_root_setup(char *line) { - 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; + 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); } - sprintf(nfs_export_path, buf, cp); + + /* + * 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); -/* - * Get NFS server address. - */ -static int __init root_nfs_addr(void) +static int __init root_nfs_copy(char *dest, const char *src, + const size_t destlen) { - if ((servaddr = root_server_addr) == htonl(INADDR_NONE)) { - printk(KERN_ERR "Root-NFS: No NFS server available, giving up.\n"); + if (strlcpy(dest, src, destlen) > destlen) return -1; - } + return 0; +} - snprintf(nfs_data.hostname, sizeof(nfs_data.hostname), - "%pI4", &servaddr); +static int __init root_nfs_cat(char *dest, const char *src, + const size_t destlen) +{ + if (strlcat(dest, src, destlen) > destlen) + return -1; return 0; } /* - * Tell the user what's going on. + * Parse out root export path and mount options from + * passed-in string @incoming. + * + * Copy the export path into @exppath. */ -#ifdef NFSROOT_DEBUG -static void __init root_nfs_print(void) +static int __init root_nfs_parse_options(char *incoming, char *exppath, + const size_t exppathlen) { - 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 - + char *p; -static int __init root_nfs_init(void) -{ -#ifdef NFSROOT_DEBUG - nfs_debug |= NFSDBG_ROOT; -#endif + /* + * Set the NFS remote path + */ + p = strsep(&incoming, ","); + if (*p != '\0' && strcmp(p, "default") != 0) + if (root_nfs_copy(exppath, p, exppathlen)) + return -1; /* - * 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). + * @incoming now points to the rest of the string; if it + * contains something, append it to our root options buffer */ - if (root_nfs_name(nfs_root_name) < 0 || - root_nfs_addr() < 0) - return -1; + if (incoming != NULL && *incoming != '\0') + if (root_nfs_cat(nfs_root_options, incoming, + sizeof(nfs_root_options))) + return -1; -#ifdef NFSROOT_DEBUG - root_nfs_print(); -#endif + /* + * Possibly prepare for more options to be appended + */ + if (nfs_root_options[0] != '\0' && + nfs_root_options[strlen(nfs_root_options)] != ',') + if (root_nfs_cat(nfs_root_options, ",", + sizeof(nfs_root_options))) + return -1; return 0; } - /* - * Parse NFS server and directory information passed on the kernel - * command line. + * Decode the export directory path name and NFS options from + * the kernel command line. This has to be done late in order to + * use a dynamically acquired client IP address for the remote + * root directory path. + * + * Returns zero if successful; otherwise -1 is returned. */ -static int __init nfs_root_setup(char *line) +static int __init root_nfs_data(char *cmdline) { - ROOT_DEV = Root_NFS; - if (line[0] == '/' || line[0] == ',' || (line[0] >= '0' && line[0] <= '9')) { - strlcpy(nfs_root_name, line, sizeof(nfs_root_name)); - } else { - int n = strlen(line) + sizeof(NFS_ROOT) - 1; - if (n >= sizeof(nfs_root_name)) - line[sizeof(nfs_root_name) - sizeof(NFS_ROOT) - 2] = '\0'; - sprintf(nfs_root_name, NFS_ROOT, line); + char addr_option[sizeof("nolock,addr=") + INET_ADDRSTRLEN + 1]; + int len, retval = -1; + char *tmp = NULL; + const size_t tmplen = sizeof(nfs_export_path); + + tmp = kzalloc(tmplen, GFP_KERNEL); + if (tmp == NULL) + goto out_nomem; + strcpy(tmp, NFS_ROOT); + + if (root_server_path[0] != '\0') { + dprintk("Root-NFS: DHCPv4 option 17: %s\n", + root_server_path); + if (root_nfs_parse_options(root_server_path, tmp, tmplen)) + goto out_optionstoolong; } - root_server_addr = root_nfs_parse_addr(nfs_root_name); - return 1; -} -__setup("nfsroot=", nfs_root_setup); - -/*************************************************************************** - - Routines to actually mount the root directory + if (cmdline[0] != '\0') { + dprintk("Root-NFS: nfsroot=%s\n", cmdline); + if (root_nfs_parse_options(cmdline, tmp, tmplen)) + goto out_optionstoolong; + } - ***************************************************************************/ + /* + * Append mandatory options for nfsroot so they override + * what has come before + */ + snprintf(addr_option, sizeof(addr_option), "nolock,addr=%pI4", + &servaddr); + if (root_nfs_cat(nfs_root_options, addr_option, + sizeof(nfs_root_options))) + goto out_optionstoolong; -/* - * 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; -} + /* + * Set up nfs_root_device. For NFS mounts, this looks like + * + * server:/path + * + * At this point, utsname()->nodename contains our local + * IP address or hostname, set by ipconfig. If "%s" exists + * in tmp, substitute the nodename, then shovel the whole + * mess into nfs_root_device. + */ + len = snprintf(nfs_export_path, sizeof(nfs_export_path), + tmp, utsname()->nodename); + if (len > (int)sizeof(nfs_export_path)) + goto out_devnametoolong; + len = snprintf(nfs_root_device, sizeof(nfs_root_device), + "%pI4:%s", &servaddr, nfs_export_path); + if (len > (int)sizeof(nfs_root_device)) + goto out_devnametoolong; -/* - * 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; + retval = 0; - 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); +out: + kfree(tmp); + return retval; +out_nomem: + printk(KERN_ERR "Root-NFS: could not allocate memory\n"); + goto out; +out_optionstoolong: + printk(KERN_ERR "Root-NFS: mount options string too long\n"); + goto out; +out_devnametoolong: + printk(KERN_ERR "Root-NFS: root device name too long.\n"); + goto out; } - -/* - * 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? +/** + * nfs_root_data - Return prepared 'data' for NFSROOT mount + * @root_device: OUT: address of string containing NFSROOT device + * @root_data: OUT: address of string containing NFSROOT mount options + * + * Returns zero and sets @root_device and @root_data if successful, + * otherwise -1 is returned. */ -static int __init root_nfs_ports(void) +int __init nfs_root_data(char **root_device, char **root_data) { - 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); + servaddr = root_server_addr; + if (servaddr == htonl(INADDR_NONE)) { + printk(KERN_ERR "Root-NFS: no NFS server address\n"); + return -1; } - 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); + if (root_nfs_data(nfs_root_parms) < 0) + return -1; + *root_device = nfs_root_device; + *root_data = nfs_root_options; 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; -} |