diff options
Diffstat (limited to 'utils/mount/nfsumount.c')
| -rw-r--r-- | utils/mount/nfsumount.c | 392 |
1 files changed, 392 insertions, 0 deletions
diff --git a/utils/mount/nfsumount.c b/utils/mount/nfsumount.c new file mode 100644 index 0000000..d1d476a --- /dev/null +++ b/utils/mount/nfsumount.c @@ -0,0 +1,392 @@ +/* + * nfsumount.c -- Linux NFS umount + * Copyright (C) 2006 Amit Gud <agud@redhat.com> + * + * - Basic code and wrapper around NFS umount code originally + * in util-linux/mount/nfsmount.c + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2, or (at your option) + * any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#include <stdio.h> +#include <errno.h> +#include <getopt.h> +#include <mntent.h> +#include <sys/mount.h> +#include <ctype.h> + +#include "xcommon.h" +#include "fstab.h" +#include "nls.h" +#include "conn.h" + +#include "mount_constants.h" +#include "nfsmount.h" +#include "nfsumount.h" + +#if !defined(MNT_FORCE) +/* dare not try to include <linux/mount.h> -- lots of errors */ +#define MNT_FORCE 1 +#endif + +#if !defined(MNT_DETACH) +#define MNT_DETACH 2 +#endif + +extern char *progname; +extern int nfs_mount_version; +extern int nomtab; +extern int verbose; +int force; +int lazy; +int remount; + +extern int find_kernel_nfs_mount_version(void); +extern int probe_mntport(clnt_addr_t *); +extern int nfs_gethostbyname(const char *, struct sockaddr_in *); + +static inline enum clnt_stat +nfs3_umount(dirpath *argp, CLIENT *clnt) +{ + static char clnt_res; + memset (&clnt_res, 0, sizeof(clnt_res)); + return clnt_call(clnt, MOUNTPROC_UMNT, + (xdrproc_t) xdr_dirpath, (caddr_t)argp, + (xdrproc_t) xdr_void, (caddr_t) &clnt_res, + TIMEOUT); +} + +static inline enum clnt_stat +nfs2_umount(dirpath *argp, CLIENT *clnt) +{ + static char clnt_res; + memset (&clnt_res, 0, sizeof(clnt_res)); + return clnt_call(clnt, MOUNTPROC_UMNT, + (xdrproc_t) xdr_dirpath, (caddr_t)argp, + (xdrproc_t) xdr_void, (caddr_t) &clnt_res, + TIMEOUT); +} + +int nfs_call_umount(clnt_addr_t *mnt_server, dirpath *argp) +{ + CLIENT *clnt; + enum clnt_stat res = 0; + int msock; + + clnt = mnt_openclnt(mnt_server, &msock); + if (!clnt) + goto out_bad; + switch (mnt_server->pmap.pm_vers) { + case 3: + res = nfs3_umount(argp, clnt); + break; + case 2: + case 1: + res = nfs2_umount(argp, clnt); + break; + default: + break; + } + mnt_closeclnt(clnt, msock); + if (res == RPC_SUCCESS) + return 1; + out_bad: + return 0; +} + +u_int get_mntproto(const char *); +u_int +get_mntproto(const char *dirname) +{ + FILE *mtab; + struct mntent mntbuf; + char tmpbuf[BUFSIZ]; + u_int proto = IPPROTO_TCP; /* assume tcp */ + + mtab = setmntent ("/proc/mounts", "r"); + if (mtab == NULL) + mtab = setmntent (_PATH_MOUNTED, "r"); + if (mtab == NULL) + return proto; + + while(getmntent_r(mtab, &mntbuf, tmpbuf, sizeof (tmpbuf))) { + if (strcmp(mntbuf.mnt_type, "nfs")) + continue; + if (strcmp(dirname, mntbuf.mnt_fsname)) + continue; + if (hasmntopt(&mntbuf, "udp")) + proto = IPPROTO_UDP; + break; + } + endmntent (mtab); + + return proto; +} + +/* complain about a failed umount */ +static void complain(int err, const char *dev) { + switch (err) { + case ENXIO: + nfs_error (_("umount: %s: invalid block device"), dev); break; + case EINVAL: + nfs_error (_("umount: %s: not mounted"), dev); break; + case EIO: + nfs_error (_("umount: %s: can't write superblock"), dev); break; + case EBUSY: + /* Let us hope fstab has a line "proc /proc ..." + and not "none /proc ..."*/ + nfs_error (_("umount: %s: device is busy"), dev); break; + case ENOENT: + nfs_error (_("umount: %s: not found"), dev); break; + case EPERM: + nfs_error (_("umount: %s: must be superuser to umount"), dev); break; + case EACCES: + nfs_error (_("umount: %s: block devices not permitted on fs"), dev); break; + default: + nfs_error (_("umount: %s: %s"), dev, strerror (err)); break; + } +} + +int add_mtab2(const char *spec, const char *node, const char *type, + const char *opts, struct mntentchn *mc) +{ + int umnt_err, umnt_err2, res; + + umnt_err = umnt_err2 = 0; + if (lazy) { + res = umount2 (node, MNT_DETACH); + if (res < 0) + umnt_err = errno; + goto writemtab; + } + + if (force) { + res = umount2 (node, MNT_FORCE); + if (res == -1) { + int errsv = errno; + perror("umount2"); + errno = errsv; + if (errno == ENOSYS) { + if (verbose) + printf(_("no umount2, trying umount...\n")); + res = umount (node); + } + } + } else + res = umount (node); + + if (res < 0) { + umnt_err = errno; + /* A device might have been mounted on a node that has since + been deleted or renamed, so if node fails, also try spec. */ + /* Note that this is incorrect in case spec was mounted + several times. */ + /* if (umnt_err == ENOENT || umnt_err == EINVAL) */ + if (umnt_err != EBUSY && strcmp(node, spec)) { + if (verbose) + printf (_("could not umount %s - trying %s instead\n"), + node, spec); + res = umount (spec); + if (res < 0) + umnt_err2 = errno; + /* Do not complain about remote NFS mount points */ + if (errno == ENOENT && index(spec, ':')) + umnt_err2 = 0; + } + } + + if (res < 0 && remount && (umnt_err == EBUSY || umnt_err2 == EBUSY)) { + /* Umount failed - let us try a remount */ + res = mount(spec, node, NULL, + MS_MGC_VAL | MS_REMOUNT | MS_RDONLY, NULL); + if (res == 0) { + nfs_mntent_t remnt; + fprintf(stderr, + _("umount: %s busy - remounted read-only\n"), + spec); + remnt.mnt_type = remnt.mnt_fsname = NULL; + remnt.mnt_dir = xstrdup(node); + remnt.mnt_opts = xstrdup("ro"); + if (!nomtab) + update_mtab(node, &remnt); + return 0; + } else if (errno != EBUSY) { /* hmm ... */ + perror("remount"); + fprintf(stderr, + _("umount: could not remount %s read-only\n"), + spec); + } + } + + if (res >= 0) { + /* Umount succeeded */ + if (verbose) + printf (_("%s umounted\n"), spec); + } + + writemtab: + if (!nomtab && + (umnt_err == 0 || umnt_err == EINVAL || umnt_err == ENOENT)) { + update_mtab (node, NULL); + } + + if (res >= 0) + return 0; + + if (umnt_err2) + complain(umnt_err2, spec); + if (umnt_err && umnt_err != umnt_err2) + complain(umnt_err, node); + return 1; +} + +/* + * Returns 1 if everything went well, else 0. + */ +int _nfsumount(const char *spec, const char *opts) +{ + char *hostname; + char *dirname; + clnt_addr_t mnt_server = { &hostname, }; + struct pmap *pmap = &mnt_server.pmap; + char *p; + + nfs_mount_version = find_kernel_nfs_mount_version(); + if (spec == NULL || (p = strchr(spec,':')) == NULL) + goto out_bad; + hostname = xstrndup(spec, p-spec); + dirname = xstrdup(p+1); +#ifdef NFS_MOUNT_DEBUG + printf(_("host: %s, directory: %s\n"), hostname, dirname); +#endif + + if (opts && (p = strstr(opts, "addr="))) { + char *q; + + free(hostname); + p += 5; + q = p; + while (*q && *q != ',') q++; + hostname = xstrndup(p,q-p); + } + + if (opts && (p = strstr(opts, "mounthost="))) { + char *q; + + free(hostname); + p += 10; + q = p; + while (*q && *q != ',') q++; + hostname = xstrndup(p,q-p); + } + + pmap->pm_prog = MOUNTPROG; + pmap->pm_vers = MOUNTVERS; + pmap->pm_prot = get_mntproto(spec); + if (opts && (p = strstr(opts, "mountprog=")) && isdigit(*(p+10))) + pmap->pm_prog = atoi(p+10); + if (opts && (p = strstr(opts, "mountport=")) && isdigit(*(p+10))) + pmap->pm_port = atoi(p+10); + if (opts && (p = strstr(opts, "nfsvers=")) && isdigit(*(p+8))) + pmap->pm_vers = nfsvers_to_mnt(atoi(p+8)); + if (opts && (p = strstr(opts, "mountvers=")) && isdigit(*(p+10))) + pmap->pm_vers = atoi(p+10); + + if (!nfs_gethostbyname(hostname, &mnt_server.saddr)) + goto out_bad; + if (!probe_mntport(&mnt_server)) + goto out_bad; + return nfs_call_umount(&mnt_server, &dirname); + out_bad: + printf("%s: %s: not found or not mounted\n", progname, spec); + return 0; +} + +static struct option umount_longopts[] = +{ + { "force", 0, 0, 'f' }, + { "help", 0, 0, 'h' }, + { "no-mtab", 0, 0, 'n' }, + { "verbose", 0, 0, 'v' }, + { "read-only", 0, 0, 'r' }, + { NULL, 0, 0, 0 } +}; + +void umount_usage() +{ + printf("usage: %s dir [-fvnrlh]\n", progname); + printf("options:\n\t-f\t\tforce unmount\n"); + printf("\t-v\t\tverbose\n"); + printf("\t-n\t\tDo not update /etc/mtab\n"); + printf("\t-r\t\tremount\n"); + printf("\t-l\t\tlazy unmount\n"); + printf("\t-h\t\tprint this help\n\n"); +} + +int nfsumount(int argc, char *argv[]) +{ + int c, ret; + char *spec; + struct mntentchn *mc; + + spec = argv[1]; + + argv += 1; + argc -= 1; + + while ((c = getopt_long (argc, argv, "fvnrlh", + umount_longopts, NULL)) != -1) { + + switch (c) { + case 'f': + ++force; + break; + case 'v': + ++verbose; + break; + case 'n': + ++nomtab; + break; + case 'r': + ++remount; + break; + case 'l': + ++lazy; + break; + case 'h': + default: + umount_usage(); + return 0; + } + } + + mc = getmntdirbackward(spec, NULL); + if (!mc) + mc = getmntdevbackward(spec, NULL); + if (!mc && verbose) + printf(_("Could not find %s in mtab\n"), spec); + + if(mc) { + ret = _nfsumount(mc->m.mnt_fsname, mc->m.mnt_opts); + if(ret) + ret = add_mtab2(mc->m.mnt_fsname, mc->m.mnt_dir, + mc->m.mnt_type, mc->m.mnt_opts, mc); + } + else { + ret = _nfsumount(spec, NULL); + if(ret) + ret = add_mtab2(spec, spec, spec, spec, NULL); + } + + return(ret); +} + |