/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or https://opensource.org/licenses/CDDL-1.0. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. * Copyright (c) 2011 Lawrence Livermore National Security, LLC. */ #include <libintl.h> #include <unistd.h> #include <sys/file.h> #include <sys/mount.h> #include <sys/mntent.h> #include <sys/stat.h> #include <libzfs.h> #include <libzutil.h> #include <locale.h> #include <getopt.h> #include <fcntl.h> #include <errno.h> #define ZS_COMMENT 0x00000000 /* comment */ #define ZS_ZFSUTIL 0x00000001 /* caller is zfs(8) */ libzfs_handle_t *g_zfs; /* * Opportunistically convert a target string into a pool name. If the * string does not represent a block device with a valid zfs label * then it is passed through without modification. */ static void parse_dataset(const char *target, char **dataset) { /* * Prior to util-linux 2.36.2, if a file or directory in the * current working directory was named 'dataset' then mount(8) * would prepend the current working directory to the dataset. * Check for it and strip the prepended path when it is added. */ char cwd[PATH_MAX]; if (getcwd(cwd, PATH_MAX) == NULL) { perror("getcwd"); return; } int len = strlen(cwd); if (strncmp(cwd, target, len) == 0) target += len; /* Assume pool/dataset is more likely */ strlcpy(*dataset, target, PATH_MAX); int fd = open(target, O_RDONLY | O_CLOEXEC); if (fd < 0) return; nvlist_t *cfg = NULL; if (zpool_read_label(fd, &cfg, NULL) == 0) { const char *nm = NULL; if (!nvlist_lookup_string(cfg, ZPOOL_CONFIG_POOL_NAME, &nm)) strlcpy(*dataset, nm, PATH_MAX); nvlist_free(cfg); } if (close(fd)) perror("close"); } /* * Update the mtab_* code to use the libmount library when it is commonly * available otherwise fallback to legacy mode. The mount(8) utility will * manage the lock file for us to prevent racing updates to /etc/mtab. */ static int mtab_is_writeable(void) { struct stat st; int error, fd; error = lstat("/etc/mtab", &st); if (error || S_ISLNK(st.st_mode)) return (0); fd = open("/etc/mtab", O_RDWR | O_CREAT, 0644); if (fd < 0) return (0); close(fd); return (1); } static int mtab_update(const char *dataset, const char *mntpoint, const char *type, const char *mntopts) { struct mntent mnt; FILE *fp; int error; mnt.mnt_fsname = (char *)dataset; mnt.mnt_dir = (char *)mntpoint; mnt.mnt_type = (char *)type; mnt.mnt_opts = (char *)(mntopts ?: ""); mnt.mnt_freq = 0; mnt.mnt_passno = 0; fp = setmntent("/etc/mtab", "a+e"); if (!fp) { (void) fprintf(stderr, gettext( "filesystem '%s' was mounted, but /etc/mtab " "could not be opened due to error: %s\n"), dataset, strerror(errno)); return (MOUNT_FILEIO); } error = addmntent(fp, &mnt); if (error) { (void) fprintf(stderr, gettext( "filesystem '%s' was mounted, but /etc/mtab " "could not be updated due to error: %s\n"), dataset, strerror(errno)); return (MOUNT_FILEIO); } (void) endmntent(fp); return (MOUNT_SUCCESS); } int main(int argc, char **argv) { zfs_handle_t *zhp; char prop[ZFS_MAXPROPLEN]; uint64_t zfs_version = 0; char mntopts[MNT_LINE_MAX] = { '\0' }; char badopt[MNT_LINE_MAX] = { '\0' }; char mtabopt[MNT_LINE_MAX] = { '\0' }; char mntpoint[PATH_MAX]; char dataset[PATH_MAX], *pdataset = dataset; unsigned long mntflags = 0, zfsflags = 0, remount = 0; int sloppy = 0, fake = 0, verbose = 0, nomtab = 0, zfsutil = 0; int error, c; (void) setlocale(LC_ALL, ""); (void) setlocale(LC_NUMERIC, "C"); (void) textdomain(TEXT_DOMAIN); opterr = 0; /* check options */ while ((c = getopt_long(argc, argv, "sfnvo:h?", 0, 0)) != -1) { switch (c) { case 's': sloppy = 1; break; case 'f': fake = 1; break; case 'n': nomtab = 1; break; case 'v': verbose++; break; case 'o': (void) strlcpy(mntopts, optarg, sizeof (mntopts)); break; case 'h': case '?': if (optopt) (void) fprintf(stderr, gettext("Invalid option '%c'\n"), optopt); (void) fprintf(stderr, gettext("Usage: mount.zfs " "[-sfnvh] [-o options] <dataset> <mountpoint>\n")); return (MOUNT_USAGE); } } argc -= optind; argv += optind; /* check that we only have two arguments */ if (argc != 2) { if (argc == 0) (void) fprintf(stderr, gettext("missing dataset " "argument\n")); else if (argc == 1) (void) fprintf(stderr, gettext("missing mountpoint argument\n")); else (void) fprintf(stderr, gettext("too many arguments\n")); (void) fprintf(stderr, "usage: mount <dataset> <mountpoint>\n"); return (MOUNT_USAGE); } parse_dataset(argv[0], &pdataset); /* canonicalize the mount point */ if (realpath(argv[1], mntpoint) == NULL) { (void) fprintf(stderr, gettext("filesystem '%s' cannot be " "mounted at '%s' due to canonicalization error: %s\n"), dataset, argv[1], strerror(errno)); return (MOUNT_SYSERR); } /* validate mount options and set mntflags */ error = zfs_parse_mount_options(mntopts, &mntflags, &zfsflags, sloppy, badopt, mtabopt); if (error) { switch (error) { case ENOMEM: (void) fprintf(stderr, gettext("filesystem '%s' " "cannot be mounted due to a memory allocation " "failure.\n"), dataset); return (MOUNT_SYSERR); case ENOENT: (void) fprintf(stderr, gettext("filesystem '%s' " "cannot be mounted due to invalid option " "'%s'.\n"), dataset, badopt); (void) fprintf(stderr, gettext("Use the '-s' option " "to ignore the bad mount option.\n")); return (MOUNT_USAGE); default: (void) fprintf(stderr, gettext("filesystem '%s' " "cannot be mounted due to internal error %d.\n"), dataset, error); return (MOUNT_SOFTWARE); } } if (mntflags & MS_REMOUNT) { nomtab = 1; remount = 1; } if (zfsflags & ZS_ZFSUTIL) zfsutil = 1; if ((g_zfs = libzfs_init()) == NULL) { (void) fprintf(stderr, "%s\n", libzfs_error_init(errno)); return (MOUNT_SYSERR); } /* try to open the dataset to access the mount point */ if ((zhp = zfs_open(g_zfs, dataset, ZFS_TYPE_FILESYSTEM | ZFS_TYPE_SNAPSHOT)) == NULL) { (void) fprintf(stderr, gettext("filesystem '%s' cannot be " "mounted, unable to open the dataset\n"), dataset); libzfs_fini(g_zfs); return (MOUNT_USAGE); } if (sloppy || libzfs_envvar_is_set("ZFS_MOUNT_HELPER")) { zfs_adjust_mount_options(zhp, mntpoint, mntopts, mtabopt); } /* treat all snapshots as legacy mount points */ if (zfs_get_type(zhp) == ZFS_TYPE_SNAPSHOT) (void) strlcpy(prop, ZFS_MOUNTPOINT_LEGACY, ZFS_MAXPROPLEN); else (void) zfs_prop_get(zhp, ZFS_PROP_MOUNTPOINT, prop, sizeof (prop), NULL, NULL, 0, B_FALSE); /* * Fetch the max supported zfs version in case we get ENOTSUP * back from the mount command, since we need the zfs handle * to do so. */ zfs_version = zfs_prop_get_int(zhp, ZFS_PROP_VERSION); if (zfs_version == 0) { fprintf(stderr, gettext("unable to fetch " "ZFS version for filesystem '%s'\n"), dataset); zfs_close(zhp); libzfs_fini(g_zfs); return (MOUNT_SYSERR); } /* * Legacy mount points may only be mounted using 'mount', never using * 'zfs mount'. However, since 'zfs mount' actually invokes 'mount' * we differentiate the two cases using the 'zfsutil' mount option. * This mount option should only be supplied by the 'zfs mount' util. * * The only exception to the above rule is '-o remount' which is * always allowed for non-legacy datasets. This is done because when * using zfs as your root file system both rc.sysinit/umountroot and * systemd depend on 'mount -o remount <mountpoint>' to work. */ if (zfsutil && (strcmp(prop, ZFS_MOUNTPOINT_LEGACY) == 0)) { (void) fprintf(stderr, gettext( "filesystem '%s' cannot be mounted using 'zfs mount'.\n" "Use 'zfs set mountpoint=%s' or 'mount -t zfs %s %s'.\n" "See zfs(8) for more information.\n"), dataset, mntpoint, dataset, mntpoint); zfs_close(zhp); libzfs_fini(g_zfs); return (MOUNT_USAGE); } if (!zfsutil && !(remount || fake) && strcmp(prop, ZFS_MOUNTPOINT_LEGACY)) { (void) fprintf(stderr, gettext( "filesystem '%s' cannot be mounted using 'mount'.\n" "Use 'zfs set mountpoint=%s' or 'zfs mount %s'.\n" "See zfs(8) for more information.\n"), dataset, "legacy", dataset); zfs_close(zhp); libzfs_fini(g_zfs); return (MOUNT_USAGE); } if (verbose) (void) fprintf(stdout, gettext("mount.zfs:\n" " dataset: \"%s\"\n mountpoint: \"%s\"\n" " mountflags: 0x%lx\n zfsflags: 0x%lx\n" " mountopts: \"%s\"\n mtabopts: \"%s\"\n"), dataset, mntpoint, mntflags, zfsflags, mntopts, mtabopt); if (!fake) { if (!remount && !sloppy && !libzfs_envvar_is_set("ZFS_MOUNT_HELPER")) { error = zfs_mount_at(zhp, mntopts, mntflags, mntpoint); if (error) { (void) fprintf(stderr, "zfs_mount_at() failed: " "%s", libzfs_error_description(g_zfs)); zfs_close(zhp); libzfs_fini(g_zfs); return (MOUNT_SYSERR); } } else { error = mount(dataset, mntpoint, MNTTYPE_ZFS, mntflags, mntopts); } } zfs_close(zhp); libzfs_fini(g_zfs); if (error) { switch (errno) { case ENOENT: (void) fprintf(stderr, gettext("mount point " "'%s' does not exist\n"), mntpoint); return (MOUNT_SYSERR); case EBUSY: (void) fprintf(stderr, gettext("filesystem " "'%s' is already mounted\n"), dataset); return (MOUNT_BUSY); case ENOTSUP: if (zfs_version > ZPL_VERSION) { (void) fprintf(stderr, gettext("filesystem '%s' (v%d) is not " "supported by this implementation of " "ZFS (max v%d).\n"), dataset, (int)zfs_version, (int)ZPL_VERSION); } else { (void) fprintf(stderr, gettext("filesystem '%s' mount " "failed for unknown reason.\n"), dataset); } return (MOUNT_SYSERR); #ifdef MS_MANDLOCK case EPERM: if (mntflags & MS_MANDLOCK) { (void) fprintf(stderr, gettext("filesystem " "'%s' has the 'nbmand=on' property set, " "this mount\noption may be disabled in " "your kernel. Use 'zfs set nbmand=off'\n" "to disable this option and try to " "mount the filesystem again.\n"), dataset); return (MOUNT_SYSERR); } #endif zfs_fallthrough; default: (void) fprintf(stderr, gettext("filesystem " "'%s' can not be mounted: %s\n"), dataset, strerror(errno)); return (MOUNT_USAGE); } } if (!nomtab && mtab_is_writeable()) { error = mtab_update(dataset, mntpoint, MNTTYPE_ZFS, mtabopt); if (error) return (error); } return (MOUNT_SUCCESS); }