X-Git-Url: https://git.camperquake.de/gitweb.cgi?a=blobdiff_plain;f=lib%2Flibzfs%2Flibzfs_mount.c;h=977b2ee31b3fa5461476ade9d04c49635767ec28;hb=9a616b5d17185c7fa5cd0d39ff8bc101cad8466d;hp=88bd0714e8a14d9c74f2642b5b715ead0cb81b0f;hpb=149e873ab174ded1f632f2b2eb2267593517c7ca;p=zfs.git diff --git a/lib/libzfs/libzfs_mount.c b/lib/libzfs/libzfs_mount.c index 88bd071..977b2ee 100644 --- a/lib/libzfs/libzfs_mount.c +++ b/lib/libzfs/libzfs_mount.c @@ -72,6 +72,9 @@ #include #include #include +#ifdef HAVE_LIBSELINUX +#include +#endif /* HAVE_LIBSELINUX */ #include @@ -118,20 +121,21 @@ zfs_share_proto_t share_all_proto[] = { }; /* - * Search the sharetab for the given mountpoint and protocol, returning + * Search for NFS and SMB exports for the given mountpoint and protocol, returning * a zfs_share_type_t value. */ static zfs_share_type_t is_shared(libzfs_handle_t *hdl, const char *mountpoint, zfs_share_proto_t proto) { char buf[MAXPATHLEN], *tab; - char *ptr; if (hdl->libzfs_sharetab == NULL) return (SHARED_NOT_SHARED); (void) fseek(hdl->libzfs_sharetab, 0, SEEK_SET); + /* Search /etc/exports for NFS exports */ + /* FIXME: Assumes the file is tab delimited. */ while (fgets(buf, sizeof (buf), hdl->libzfs_sharetab) != NULL) { /* the mountpoint is the first entry on each line */ @@ -140,31 +144,15 @@ is_shared(libzfs_handle_t *hdl, const char *mountpoint, zfs_share_proto_t proto) *tab = '\0'; if (strcmp(buf, mountpoint) == 0) { - /* - * the protocol field is the third field - * skip over second field - */ - ptr = ++tab; - if ((tab = strchr(ptr, '\t')) == NULL) - continue; - ptr = ++tab; - if ((tab = strchr(ptr, '\t')) == NULL) - continue; - *tab = '\0'; - if (strcmp(ptr, - proto_table[proto].p_name) == 0) { - switch (proto) { - case PROTO_NFS: - return (SHARED_NFS); - case PROTO_SMB: - return (SHARED_SMB); - default: - return (0); - } - } + if (proto == PROTO_NFS) + return (SHARED_NFS); + else + return (SHARED_NOT_SHARED); } } + /* XXX: Search /etc/samba/smb.conf for SMB exports, return SHARED_SMB */ + return (SHARED_NOT_SHARED); } @@ -256,6 +244,82 @@ zfs_is_mountable(zfs_handle_t *zhp, char *buf, size_t buflen, } /* + * The filesystem is mounted by invoking the system mount utility rather + * than by the system call mount(2). This ensures that the /etc/mtab + * file is correctly locked for the update. Performing our own locking + * and /etc/mtab update requires making an unsafe assumption about how + * the mount utility performs its locking. Unfortunately, this also means + * in the case of a mount failure we do not have the exact errno. We must + * make due with return value from the mount process. + * + * In the long term a shared library called libmount is under development + * which provides a common API to address the locking and errno issues. + * Once the standard mount utility has been updated to use this library + * we can add an autoconf check to conditionally use it. + * + * http://www.kernel.org/pub/linux/utils/util-linux/libmount-docs/index.html + */ + +static int +do_mount(const char *src, const char *mntpt, char *opts) +{ + char *argv[8] = { + "/bin/mount", + "-t", MNTTYPE_ZFS, + "-o", opts, + (char *)src, + (char *)mntpt, + (char *)NULL }; + int rc; + + /* Return only the most critical mount error */ + rc = libzfs_run_process(argv[0], argv); + if (rc) { + if (rc & MOUNT_FILEIO) + return EIO; + if (rc & MOUNT_USER) + return EINTR; + if (rc & MOUNT_SOFTWARE) + return EPIPE; + if (rc & MOUNT_SYSERR) + return EAGAIN; + if (rc & MOUNT_USAGE) + return EINVAL; + + return ENXIO; /* Generic error */ + } + + return 0; +} + +static int +do_unmount(const char *mntpt, int flags) +{ + char force_opt[] = "-f"; + char lazy_opt[] = "-l"; + char *argv[7] = { + "/bin/umount", + "-t", MNTTYPE_ZFS, + NULL, NULL, NULL, NULL }; + int rc, count = 3; + + if (flags & MS_FORCE) { + argv[count] = force_opt; + count++; + } + + if (flags & MS_DETACH) { + argv[count] = lazy_opt; + count++; + } + + argv[count] = (char *)mntpt; + rc = libzfs_run_process(argv[0], argv); + + return (rc ? EINVAL : 0); +} + +/* * Mount the given filesystem. */ int @@ -265,9 +329,10 @@ zfs_mount(zfs_handle_t *zhp, const char *options, int flags) char mountpoint[ZFS_MAXPROPLEN]; char mntopts[MNT_LINE_MAX]; libzfs_handle_t *hdl = zhp->zfs_hdl; + int rc; if (options == NULL) - mntopts[0] = '\0'; + (void) strlcpy(mntopts, MNTOPT_DEFAULTS, sizeof (mntopts)); else (void) strlcpy(mntopts, options, sizeof (mntopts)); @@ -275,7 +340,18 @@ zfs_mount(zfs_handle_t *zhp, const char *options, int flags) * If the pool is imported read-only then all mounts must be read-only */ if (zpool_get_prop_int(zhp->zpool_hdl, ZPOOL_PROP_READONLY, NULL)) - flags |= MS_RDONLY; + (void) strlcat(mntopts, "," MNTOPT_RO, sizeof (mntopts)); + + /* + * Append zfsutil option so the mount helper allow the mount + */ + strlcat(mntopts, "," MNTOPT_ZFSUTIL, sizeof (mntopts)); + +#ifdef HAVE_LIBSELINUX + if (is_selinux_enabled()) + (void) strlcat(mntopts, ",context=\"system_u:" + "object_r:file_t:s0\"", sizeof (mntopts)); +#endif /* HAVE_LIBSELINUX */ if (!zfs_is_mountable(zhp, mountpoint, sizeof (mountpoint), NULL)) return (0); @@ -293,12 +369,9 @@ zfs_mount(zfs_handle_t *zhp, const char *options, int flags) /* * Determine if the mountpoint is empty. If so, refuse to perform the - * mount. We don't perform this check if MS_OVERLAY is specified, which - * would defeat the point. We also avoid this check if 'remount' is - * specified. + * mount. We don't perform this check if 'remount' is specified. */ - if ((flags & MS_OVERLAY) == 0 && - strstr(mntopts, MNTOPT_REMOUNT) == NULL && + if (strstr(mntopts, MNTOPT_REMOUNT) == NULL && !dir_is_empty(mountpoint)) { zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, "directory is not empty")); @@ -307,20 +380,20 @@ zfs_mount(zfs_handle_t *zhp, const char *options, int flags) } /* perform the mount */ - if (mount(zfs_get_name(zhp), mountpoint, MS_OPTIONSTR | flags, - MNTTYPE_ZFS, NULL, 0, mntopts, sizeof (mntopts)) != 0) { + rc = do_mount(zfs_get_name(zhp), mountpoint, mntopts); + if (rc) { /* * Generic errors are nasty, but there are just way too many * from mount(), and they're well-understood. We pick a few * common ones to improve upon. */ - if (errno == EBUSY) { + if (rc == EBUSY) { zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, "mountpoint or dataset is busy")); - } else if (errno == EPERM) { + } else if (rc == EPERM) { zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, "Insufficient privileges")); - } else if (errno == ENOTSUP) { + } else if (rc == ENOTSUP) { char buf[256]; int spa_version; @@ -333,7 +406,7 @@ zfs_mount(zfs_handle_t *zhp, const char *options, int flags) ZFS_PROP_VERSION), spa_version); zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, buf)); } else { - zfs_error_aux(hdl, strerror(errno)); + zfs_error_aux(hdl, strerror(rc)); } return (zfs_error_fmt(hdl, EZFS_MOUNTFAILED, dgettext(TEXT_DOMAIN, "cannot mount '%s'"), @@ -341,8 +414,7 @@ zfs_mount(zfs_handle_t *zhp, const char *options, int flags) } /* add the mounted entry into our cache */ - libzfs_mnttab_add(hdl, zfs_get_name(zhp), mountpoint, - mntopts); + libzfs_mnttab_add(hdl, zfs_get_name(zhp), mountpoint, mntopts); return (0); } @@ -352,7 +424,7 @@ zfs_mount(zfs_handle_t *zhp, const char *options, int flags) static int unmount_one(libzfs_handle_t *hdl, const char *mountpoint, int flags) { - if (umount2(mountpoint, flags) != 0) { + if (do_unmount(mountpoint, flags) != 0) { zfs_error_aux(hdl, strerror(errno)); return (zfs_error_fmt(hdl, EZFS_UMOUNTFAILED, dgettext(TEXT_DOMAIN, "cannot unmount '%s'"), @@ -721,10 +793,12 @@ zfs_share_proto(zfs_handle_t *zhp, zfs_share_proto_t *proto) return (0); if ((ret = zfs_init_libshare(hdl, SA_INIT_SHARE_API)) != SA_OK) { +#ifdef HAVE_SHARE (void) zfs_error_fmt(hdl, EZFS_SHARENFSFAILED, dgettext(TEXT_DOMAIN, "cannot share '%s': %s"), zfs_get_name(zhp), _sa_errorstr != NULL ? _sa_errorstr(ret) : ""); +#endif /* HAVE_SHARE */ return (-1); } @@ -1138,7 +1212,7 @@ mountpoint_compare(const void *a, const void *b) * Unshare and unmount all datasets within the given pool. We don't want to * rely on traversing the DSL to discover the filesystems within the pool, * because this may be expensive (if not all of them are mounted), and can fail - * arbitrarily (on I/O error, for example). Instead, we walk /etc/mnttab and + * arbitrarily (on I/O error, for example). Instead, we walk /etc/mtab and * gather all the filesystems that are currently mounted. */ int