1 files changed, 171 insertions, 396 deletions

diff --git a/fs/nfs/nfsroot.c b/fs/nfs/nfsroot.c
index df101d9f546a..c4744e1d513c 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 +66,244 @@
  *      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"
 
+/* Default NFSROOT mount options. */
+#define NFS_DEF_OPTIONS         "vers=2,udp,rsize=4096,wsize=4096"
+
 /* 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 = NFS_DEF_OPTIONS;
 
 /* 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}
-        
-};
-
-/*
- *  Parse option string.
- */
-
-static int __init root_nfs_parse(char *name, char *buf)
-{
+static char nfs_export_path[NFS_MAXPATHLEN + 1] __initdata = "";
 
-        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;
-}
+/* server:export path string passed to super.c */
+static char nfs_root_device[NFS_MAXPATHLEN + 1] __initdata = "";
 
+#ifdef RPC_DEBUG
 /*
- *  Prepare the NFS data structure and parse all options.
+ * When the "nfsrootdebug" kernel command line option is specified,
+ * enable debugging messages for NFSROOT.
  */
-static int __init root_nfs_name(char *name)
+static int __init nfs_root_debug(char *__unused)
 {
-        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);
-
+        nfs_debug |= NFSDBG_ROOT | NFSDBG_MOUNT;
         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;
+__setup("nfsrootdebug", nfs_root_debug);
 #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.
+ *
+ *  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_name, line, sizeof(nfs_root_name));
+                strlcpy(nfs_root_parms, line, sizeof(nfs_root_parms));
         } 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);
+                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);
         }
-        root_server_addr = root_nfs_parse_addr(nfs_root_name);
+
+        /*
+         * 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);
 
-/***************************************************************************
+static int __init root_nfs_copy(char *dest, const char *src,
+                                     const size_t destlen)
+{
+        if (strlcpy(dest, src, destlen) > destlen)
+                return -1;
+        return 0;
+}
 
-               Routines to actually mount the root directory
+static int __init root_nfs_cat(char *dest, const char *src,
+                               const size_t destlen)
+{
+        size_t len = strlen(dest);
 
- ***************************************************************************/
+        if (len && dest[len - 1] != ',')
+                if (strlcat(dest, ",", destlen) > destlen)
+                        return -1;
 
-/*
- *  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;
+        if (strlcat(dest, src, destlen) > destlen)
+                return -1;
+        return 0;
 }
 
 /*
- *  Query server portmapper for the port of a daemon program.
+ * Parse out root export path and mount options from
+ * passed-in string @incoming.
+ *
+ * Copy the export path into @exppath.
  */
-static int __init root_nfs_getport(int program, int version, int proto)
+static int __init root_nfs_parse_options(char *incoming, char *exppath,
+                                         const size_t exppathlen)
 {
-        struct sockaddr_in sin;
+        char *p;
 
-        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);
-}
+        /*
+         * Set the NFS remote path
+         */
+        p = strsep(&incoming, ",");
+        if (*p != '\0' && strcmp(p, "default") != 0)
+                if (root_nfs_copy(exppath, p, exppathlen))
+                        return -1;
 
+        /*
+         * @incoming now points to the rest of the string; if it
+         * contains something, append it to our root options buffer
+         */
+        if (incoming != NULL && *incoming != '\0')
+                if (root_nfs_cat(nfs_root_options, incoming,
+                                                sizeof(nfs_root_options)))
+                        return -1;
+        return 0;
+}
 
 /*
- *  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?
+ *  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 root_nfs_ports(void)
+static int __init root_nfs_data(char *cmdline)
 {
-        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;
+        char mand_options[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;
         }
 
-        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 (cmdline[0] != '\0') {
+                dprintk("Root-NFS: nfsroot=%s\n", cmdline);
+                if (root_nfs_parse_options(cmdline, tmp, tmplen))
+                        goto out_optionstoolong;
         }
 
-        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);
+        /*
+         * Append mandatory options for nfsroot so they override
+         * what has come before
+         */
+        snprintf(mand_options, sizeof(mand_options), "nolock,addr=%pI4",
+                        &servaddr);
+        if (root_nfs_cat(nfs_root_options, mand_options,
+                                                sizeof(nfs_root_options)))
+                goto out_optionstoolong;
 
-        return 0;
-}
+        /*
+         * 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;
 
+        retval = 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;
+        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;
 }
 
-/*
- *  Get the NFS port numbers and file handle, and return the prepared 'data'
- *  argument for mount() if everything went OK. Return NULL otherwise.
+/**
+ * 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.
  */
-void * __init nfs_root_data(void)
+int __init nfs_root_data(char **root_device, char **root_data)
 {
-        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;
+        servaddr = root_server_addr;
+        if (servaddr == htonl(INADDR_NONE)) {
+                printk(KERN_ERR "Root-NFS: no NFS server address\n");
+                return -1;
+        }
+
+        if (root_nfs_data(nfs_root_parms) < 0)
+                return -1;
+
+        *root_device = nfs_root_device;
+        *root_data = nfs_root_options;
+        return 0;
 }