diff options
Diffstat (limited to 'sys/kern/vfs_mount.c')
| -rw-r--r-- | sys/kern/vfs_mount.c | 1792 |
1 files changed, 1792 insertions, 0 deletions
diff --git a/sys/kern/vfs_mount.c b/sys/kern/vfs_mount.c new file mode 100644 index 0000000..7d166f0 --- /dev/null +++ b/sys/kern/vfs_mount.c @@ -0,0 +1,1792 @@ +/* + * Copyright (c) 1989, 1993 + * The Regents of the University of California. All rights reserved. + * (c) UNIX System Laboratories, Inc. + * All or some portions of this file are derived from material licensed + * to the University of California by American Telephone and Telegraph + * Co. or Unix System Laboratories, Inc. and are reproduced herein with + * the permission of UNIX System Laboratories, Inc. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * Copyright (c) 1999 Michael Smith + * All rights reserved. + * Copyright (c) 1999 Poul-Henning Kamp + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/param.h> +#include <sys/conf.h> +#include <sys/cons.h> +#include <sys/kernel.h> +#include <sys/linker.h> +#include <sys/mac.h> +#include <sys/malloc.h> +#include <sys/mount.h> +#include <sys/mutex.h> +#include <sys/namei.h> +#include <sys/proc.h> +#include <sys/filedesc.h> +#include <sys/reboot.h> +#include <sys/sysproto.h> +#include <sys/sx.h> +#include <sys/sysctl.h> +#include <sys/sysent.h> +#include <sys/systm.h> +#include <sys/vnode.h> + +#include <geom/geom.h> + +#include <machine/stdarg.h> + +#include "opt_rootdevname.h" +#include "opt_ddb.h" +#include "opt_mac.h" + +#ifdef DDB +#include <ddb/ddb.h> +#endif + +#define ROOTNAME "root_device" + +static void checkdirs(struct vnode *olddp, struct vnode *newdp); +static int vfs_nmount(struct thread *td, int, struct uio *); +static int vfs_mountroot_try(char *mountfrom); +static int vfs_mountroot_ask(void); +static void gets(char *cp); + +static int usermount = 0; /* if 1, non-root can mount fs. */ +SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, ""); + +MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure"); + +/* List of mounted filesystems. */ +struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); + +/* For any iteration/modification of mountlist */ +struct mtx mountlist_mtx; + +/* For any iteration/modification of mnt_vnodelist */ +struct mtx mntvnode_mtx; + +/* + * The vnode of the system's root (/ in the filesystem, without chroot + * active.) + */ +struct vnode *rootvnode; + +/* + * The root filesystem is detailed in the kernel environment variable + * vfs.root.mountfrom, which is expected to be in the general format + * + * <vfsname>:[<path>] + * vfsname := the name of a VFS known to the kernel and capable + * of being mounted as root + * path := disk device name or other data used by the filesystem + * to locate its physical store + */ + +/* + * The root specifiers we will try if RB_CDROM is specified. + */ +static char *cdrom_rootdevnames[] = { + "cd9660:cd0a", + "cd9660:acd0a", + "cd9660:wcd0a", + NULL +}; + +/* legacy find-root code */ +char *rootdevnames[2] = {NULL, NULL}; +static int setrootbyname(char *name); +dev_t rootdev = NODEV; + +/* + * Has to be dynamic as the value of rootdev can change; however, it can't + * change after the root is mounted, so a user process can't access this + * sysctl until after the value is unchangeable. + */ +static int +sysctl_rootdev(SYSCTL_HANDLER_ARGS) +{ + int error; + + /* _RD prevents this from happening. */ + KASSERT(req->newptr == NULL, ("Attempt to change root device name")); + + if (rootdev != NODEV) + error = sysctl_handle_string(oidp, rootdev->si_name, 0, req); + else + error = sysctl_handle_string(oidp, "", 0, req); + + return (error); +} + +SYSCTL_PROC(_kern, OID_AUTO, rootdev, CTLTYPE_STRING | CTLFLAG_RD, + 0, 0, sysctl_rootdev, "A", "Root file system device"); + +/* Remove one mount option. */ +static void +vfs_freeopt(struct vfsoptlist *opts, struct vfsopt *opt) +{ + + TAILQ_REMOVE(opts, opt, link); + free(opt->name, M_MOUNT); + if (opt->value != NULL) + free(opt->value, M_MOUNT); +#ifdef INVARIANTS + else if (opt->len != 0) + panic("%s: mount option with NULL value but length != 0", + __func__); +#endif + free(opt, M_MOUNT); +} + +/* Release all resources related to the mount options. */ +static void +vfs_freeopts(struct vfsoptlist *opts) +{ + struct vfsopt *opt; + + while (!TAILQ_EMPTY(opts)) { + opt = TAILQ_FIRST(opts); + vfs_freeopt(opts, opt); + } + free(opts, M_MOUNT); +} + +/* + * If a mount option is specified several times, + * (with or without the "no" prefix) only keep + * the last occurence of it. + */ +static void +vfs_sanitizeopts(struct vfsoptlist *opts) +{ + struct vfsopt *opt, *opt2, *tmp; + int noopt; + + TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) { + if (strncmp(opt->name, "no", 2) == 0) + noopt = 1; + else + noopt = 0; + opt2 = TAILQ_PREV(opt, vfsoptlist, link); + while (opt2 != NULL) { + if (strcmp(opt2->name, opt->name) == 0 || + (noopt && strcmp(opt->name + 2, opt2->name) == 0) || + (!noopt && strncmp(opt2->name, "no", 2) == 0 && + strcmp(opt2->name + 2, opt->name) == 0)) { + tmp = TAILQ_PREV(opt2, vfsoptlist, link); + vfs_freeopt(opts, opt2); + opt2 = tmp; + } else { + opt2 = TAILQ_PREV(opt2, vfsoptlist, link); + } + } + } +} + +/* + * Build a linked list of mount options from a struct uio. + */ +static int +vfs_buildopts(struct uio *auio, struct vfsoptlist **options) +{ + struct vfsoptlist *opts; + struct vfsopt *opt; + unsigned int i, iovcnt; + int error, namelen, optlen; + + iovcnt = auio->uio_iovcnt; + opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); + TAILQ_INIT(opts); + for (i = 0; i < iovcnt; i += 2) { + opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); + namelen = auio->uio_iov[i].iov_len; + optlen = auio->uio_iov[i + 1].iov_len; + opt->name = malloc(namelen, M_MOUNT, M_WAITOK); + opt->value = NULL; + if (auio->uio_segflg == UIO_SYSSPACE) { + bcopy(auio->uio_iov[i].iov_base, opt->name, namelen); + } else { + error = copyin(auio->uio_iov[i].iov_base, opt->name, + namelen); + if (error) + goto bad; + } + opt->len = optlen; + if (optlen != 0) { + opt->value = malloc(optlen, M_MOUNT, M_WAITOK); + if (auio->uio_segflg == UIO_SYSSPACE) { + bcopy(auio->uio_iov[i + 1].iov_base, opt->value, + optlen); + } else { + error = copyin(auio->uio_iov[i + 1].iov_base, + opt->value, optlen); + if (error) + goto bad; + } + } + TAILQ_INSERT_TAIL(opts, opt, link); + } + vfs_sanitizeopts(opts); + *options = opts; + return (0); +bad: + vfs_freeopts(opts); + return (error); +} + +/* + * Merge the old mount options with the new ones passed + * in the MNT_UPDATE case. + */ +static void +vfs_mergeopts(struct vfsoptlist *toopts, struct vfsoptlist *opts) +{ + struct vfsopt *opt, *opt2, *new; + + TAILQ_FOREACH(opt, opts, link) { + /* + * Check that this option hasn't been redefined + * nor cancelled with a "no" mount option. + */ + opt2 = TAILQ_FIRST(toopts); + while (opt2 != NULL) { + if (strcmp(opt2->name, opt->name) == 0) + goto next; + if (strncmp(opt2->name, "no", 2) == 0 && + strcmp(opt2->name + 2, opt->name) == 0) { + vfs_freeopt(toopts, opt2); + goto next; + } + opt2 = TAILQ_NEXT(opt2, link); + } + /* We want this option, duplicate it. */ + new = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); + new->name = malloc(strlen(opt->name) + 1, M_MOUNT, M_WAITOK); + strcpy(new->name, opt->name); + if (opt->len != 0) { + new->value = malloc(opt->len, M_MOUNT, M_WAITOK); + bcopy(opt->value, new->value, opt->len); + } else { + new->value = NULL; + } + new->len = opt->len; + TAILQ_INSERT_TAIL(toopts, new, link); +next: + continue; + } +} + +/* + * New mount API. + */ +int +nmount(td, uap) + struct thread *td; + struct nmount_args /* { + struct iovec *iovp; + unsigned int iovcnt; + int flags; + } */ *uap; +{ + struct uio auio; + struct iovec *iov, *needfree; + struct iovec aiov[UIO_SMALLIOV]; + unsigned int i; + int error; + u_int iovlen, iovcnt; + + iovcnt = uap->iovcnt; + iovlen = iovcnt * sizeof (struct iovec); + /* + * Check that we have an even number of iovec's + * and that we have at least two options. + */ + if ((iovcnt & 1) || (iovcnt < 4) || (iovcnt > UIO_MAXIOV)) + return (EINVAL); + + if (iovcnt > UIO_SMALLIOV) { + MALLOC(iov, struct iovec *, iovlen, M_IOV, M_WAITOK); + needfree = iov; + } else { + iov = aiov; + needfree = NULL; + } + auio.uio_iov = iov; + auio.uio_iovcnt = iovcnt; + auio.uio_segflg = UIO_USERSPACE; + if ((error = copyin(uap->iovp, iov, iovlen))) + goto finish; + + for (i = 0; i < iovcnt; i++) { + if (iov->iov_len > MMAXOPTIONLEN) { + error = EINVAL; + goto finish; + } + iov++; + } + error = vfs_nmount(td, uap->flags, &auio); +finish: + if (needfree != NULL) + free(needfree, M_TEMP); + return (error); +} + +int +kernel_mount(iovp, iovcnt, flags) + struct iovec *iovp; + unsigned int iovcnt; + int flags; +{ + struct uio auio; + int error; + + /* + * Check that we have an even number of iovec's + * and that we have at least two options. + */ + if ((iovcnt & 1) || (iovcnt < 4)) + return (EINVAL); + + auio.uio_iov = iovp; + auio.uio_iovcnt = iovcnt; + auio.uio_segflg = UIO_SYSSPACE; + + error = vfs_nmount(curthread, flags, &auio); + return (error); +} + +int +kernel_vmount(int flags, ...) +{ + struct iovec *iovp; + struct uio auio; + va_list ap; + unsigned int iovcnt, iovlen, len; + const char *cp; + char *buf, *pos; + size_t n; + int error, i; + + len = 0; + va_start(ap, flags); + for (iovcnt = 0; (cp = va_arg(ap, const char *)) != NULL; iovcnt++) + len += strlen(cp) + 1; + va_end(ap); + + if (iovcnt < 4 || iovcnt & 1) + return (EINVAL); + + iovlen = iovcnt * sizeof (struct iovec); + MALLOC(iovp, struct iovec *, iovlen, M_MOUNT, M_WAITOK); + MALLOC(buf, char *, len, M_MOUNT, M_WAITOK); + pos = buf; + va_start(ap, flags); + for (i = 0; i < iovcnt; i++) { + cp = va_arg(ap, const char *); + copystr(cp, pos, len - (pos - buf), &n); + iovp[i].iov_base = pos; + iovp[i].iov_len = n; + pos += n; + } + va_end(ap); + + auio.uio_iov = iovp; + auio.uio_iovcnt = iovcnt; + auio.uio_segflg = UIO_SYSSPACE; + + error = vfs_nmount(curthread, flags, &auio); + FREE(iovp, M_MOUNT); + FREE(buf, M_MOUNT); + return (error); +} + +/* + * vfs_nmount(): actually attempt a filesystem mount. + */ +static int +vfs_nmount(td, fsflags, fsoptions) + struct thread *td; + int fsflags; /* Flags common to all filesystems. */ + struct uio *fsoptions; /* Options local to the filesystem. */ +{ + linker_file_t lf; + struct vnode *vp; + struct mount *mp; + struct vfsconf *vfsp; + struct vfsoptlist *optlist; + char *fstype, *fspath; + int error, flag = 0, kern_flag = 0; + int fstypelen, fspathlen; + struct vattr va; + struct nameidata nd; + + error = vfs_buildopts(fsoptions, &optlist); + if (error) + return (error); + + /* + * We need these two options before the others, + * and they are mandatory for any filesystem. + * Ensure they are NUL terminated as well. + */ + fstypelen = 0; + error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); + if (error || fstype[fstypelen - 1] != '\0') { + error = EINVAL; + goto bad; + } + fspathlen = 0; + error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); + if (error || fspath[fspathlen - 1] != '\0') { + error = EINVAL; + goto bad; + } + + /* + * Be ultra-paranoid about making sure the type and fspath + * variables will fit in our mp buffers, including the + * terminating NUL. + */ + if (fstypelen >= MFSNAMELEN - 1 || fspathlen >= MNAMELEN - 1) { + error = ENAMETOOLONG; + goto bad; + } + + if (usermount == 0) { + error = suser(td); + if (error) + goto bad; + } + /* + * Do not allow NFS export by non-root users. + */ + if (fsflags & MNT_EXPORTED) { + error = suser(td); + if (error) + goto bad; + } + /* + * Silently enforce MNT_NOSUID and MNT_NODEV for non-root users. + */ + if (suser(td)) + fsflags |= MNT_NOSUID | MNT_NODEV; + /* + * Get vnode to be covered + */ + NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspath, td); + if ((error = namei(&nd)) != 0) + goto bad; + NDFREE(&nd, NDF_ONLY_PNBUF); + vp = nd.ni_vp; + if (fsflags & MNT_UPDATE) { + if ((vp->v_vflag & VV_ROOT) == 0) { + vput(vp); + error = EINVAL; + goto bad; + } + mp = vp->v_mount; + flag = mp->mnt_flag; + kern_flag = mp->mnt_kern_flag; + /* + * We only allow the filesystem to be reloaded if it + * is currently mounted read-only. + */ + if ((fsflags & MNT_RELOAD) && + ((mp->mnt_flag & MNT_RDONLY) == 0)) { + vput(vp); + error = EOPNOTSUPP; /* Needs translation */ + goto bad; + } + /* + * Only root, or the user that did the original mount is + * permitted to update it. + */ + if (mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { + error = suser(td); + if (error) { + vput(vp); + goto bad; + } + } + if (vfs_busy(mp, LK_NOWAIT, 0, td)) { + vput(vp); + error = EBUSY; + goto bad; + } + VI_LOCK(vp); + if ((vp->v_iflag & VI_MOUNT) != 0 || + vp->v_mountedhere != NULL) { + VI_UNLOCK(vp); + vfs_unbusy(mp, td); + vput(vp); + error = EBUSY; + goto bad; + } + vp->v_iflag |= VI_MOUNT; + VI_UNLOCK(vp); + mp->mnt_flag |= fsflags & + (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_SNAPSHOT); + VOP_UNLOCK(vp, 0, td); + mp->mnt_optnew = optlist; + vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); + goto update; + } + /* + * If the user is not root, ensure that they own the directory + * onto which we are attempting to mount. + */ + error = VOP_GETATTR(vp, &va, td->td_ucred, td); + if (error) { + vput(vp); + goto bad; + } + if (va.va_uid != td->td_ucred->cr_uid) { + error = suser(td); + if (error) { + vput(vp); + goto bad; + } + } + if ((error = vinvalbuf(vp, V_SAVE, td->td_ucred, td, 0, 0)) != 0) { + vput(vp); + goto bad; + } + if (vp->v_type != VDIR) { + vput(vp); + error = ENOTDIR; + goto bad; + } + for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) + if (!strcmp(vfsp->vfc_name, fstype)) + break; + if (vfsp == NULL) { + /* Only load modules for root (very important!). */ + error = suser(td); + if (error) { + vput(vp); + goto bad; + } + error = securelevel_gt(td->td_ucred, 0); + if (error) { + vput(vp); + goto bad; + } + error = linker_load_module(NULL, fstype, NULL, NULL, &lf); + if (error || lf == NULL) { + vput(vp); + if (lf == NULL) + error = ENODEV; + goto bad; + } + lf->userrefs++; + /* Look up again to see if the VFS was loaded. */ + for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) + if (!strcmp(vfsp->vfc_name, fstype)) + break; + if (vfsp == NULL) { + lf->userrefs--; + linker_file_unload(lf); + vput(vp); + error = ENODEV; + goto bad; + } + } + VI_LOCK(vp); + if ((vp->v_iflag & VI_MOUNT) != 0 || + vp->v_mountedhere != NULL) { + VI_UNLOCK(vp); + vput(vp); + error = EBUSY; + goto bad; + } + vp->v_iflag |= VI_MOUNT; + VI_UNLOCK(vp); + + /* + * Allocate and initialize the filesystem. + */ + mp = malloc(sizeof(struct mount), M_MOUNT, M_WAITOK | M_ZERO); + TAILQ_INIT(&mp->mnt_nvnodelist); + TAILQ_INIT(&mp->mnt_reservedvnlist); + mp->mnt_nvnodelistsize = 0; + lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, LK_NOPAUSE); + (void)vfs_busy(mp, LK_NOWAIT, 0, td); + mp->mnt_op = vfsp->vfc_vfsops; + mp->mnt_vfc = vfsp; + vfsp->vfc_refcount++; + mp->mnt_stat.f_type = vfsp->vfc_typenum; + mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK; + strlcpy(mp->mnt_stat.f_fstypename, fstype, MFSNAMELEN); + mp->mnt_vnodecovered = vp; + mp->mnt_cred = crdup(td->td_ucred); + mp->mnt_stat.f_owner = td->td_ucred->cr_uid; + strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); + mp->mnt_iosize_max = DFLTPHYS; +#ifdef MAC + mac_init_mount(mp); + mac_create_mount(td->td_ucred, mp); +#endif + VOP_UNLOCK(vp, 0, td); + mp->mnt_optnew = optlist; /* XXXMAC: should this be above? */ + +update: + /* + * Check if the fs implements the new VFS_NMOUNT() + * function, since the new system call was used. + */ + if (mp->mnt_op->vfs_mount != NULL) { + printf("%s doesn't support the new mount syscall\n", + mp->mnt_vfc->vfc_name); + VI_LOCK(vp); + vp->v_iflag &= ~VI_MOUNT; + VI_UNLOCK(vp); + if (mp->mnt_flag & MNT_UPDATE) + vfs_unbusy(mp, td); + else { + mp->mnt_vfc->vfc_refcount--; + vfs_unbusy(mp, td); +#ifdef MAC + mac_destroy_mount(mp); +#endif + crfree(mp->mnt_cred); + free(mp, M_MOUNT); + } + vrele(vp); + error = EOPNOTSUPP; + goto bad; + } + + /* + * Set the mount level flags. + */ + if (fsflags & MNT_RDONLY) + mp->mnt_flag |= MNT_RDONLY; + else if (mp->mnt_flag & MNT_RDONLY) + mp->mnt_kern_flag |= MNTK_WANTRDWR; + mp->mnt_flag &=~ MNT_UPDATEMASK; + mp->mnt_flag |= fsflags & (MNT_UPDATEMASK | MNT_FORCE); + /* + * Mount the filesystem. + * XXX The final recipients of VFS_MOUNT just overwrite the ndp they + * get. No freeing of cn_pnbuf. + */ + error = VFS_NMOUNT(mp, &nd, td); + if (!error) { + if (mp->mnt_opt != NULL) + vfs_freeopts(mp->mnt_opt); + mp->mnt_opt = mp->mnt_optnew; + } + /* + * Prevent external consumers of mount + * options to read mnt_optnew. + */ + mp->mnt_optnew = NULL; + if (mp->mnt_flag & MNT_UPDATE) { + if (mp->mnt_kern_flag & MNTK_WANTRDWR) + mp->mnt_flag &= ~MNT_RDONLY; + mp->mnt_flag &=~ + (MNT_UPDATE | MNT_RELOAD | MNT_FORCE | MNT_SNAPSHOT); + mp->mnt_kern_flag &=~ MNTK_WANTRDWR; + if (error) { + mp->mnt_flag = flag; + mp->mnt_kern_flag = kern_flag; + } + if ((mp->mnt_flag & MNT_RDONLY) == 0) { + if (mp->mnt_syncer == NULL) + error = vfs_allocate_syncvnode(mp); + } else { + if (mp->mnt_syncer != NULL) + vrele(mp->mnt_syncer); + mp->mnt_syncer = NULL; + } + vfs_unbusy(mp, td); + VI_LOCK(vp); + vp->v_iflag &= ~VI_MOUNT; + VI_UNLOCK(vp); + vrele(vp); + return (error); + } + vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); + /* + * Put the new filesystem on the mount list after root. + */ + cache_purge(vp); + if (!error) { + struct vnode *newdp; + + VI_LOCK(vp); + vp->v_iflag &= ~VI_MOUNT; + VI_UNLOCK(vp); + vp->v_mountedhere = mp; + mtx_lock(&mountlist_mtx); + TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); + mtx_unlock(&mountlist_mtx); + if (VFS_ROOT(mp, &newdp)) + panic("mount: lost mount"); + checkdirs(vp, newdp); + vput(newdp); + VOP_UNLOCK(vp, 0, td); + if ((mp->mnt_flag & MNT_RDONLY) == 0) + error = vfs_allocate_syncvnode(mp); + vfs_unbusy(mp, td); + if ((error = VFS_START(mp, 0, td)) != 0) { + vrele(vp); + goto bad; + } + } else { + VI_LOCK(vp); + vp->v_iflag &= ~VI_MOUNT; + VI_UNLOCK(vp); + mp->mnt_vfc->vfc_refcount--; + vfs_unbusy(mp, td); +#ifdef MAC + mac_destroy_mount(mp); +#endif + crfree(mp->mnt_cred); + free(mp, M_MOUNT); + vput(vp); + goto bad; + } + return (0); +bad: + vfs_freeopts(optlist); + return (error); +} + +/* + * Old mount API. + */ +#ifndef _SYS_SYSPROTO_H_ +struct mount_args { + char *type; + char *path; + int flags; + caddr_t data; +}; +#endif +/* ARGSUSED */ +int +mount(td, uap) + struct thread *td; + struct mount_args /* { + char *type; + char *path; + int flags; + caddr_t data; + } */ *uap; +{ + char *fstype; + char *fspath; + int error; + + fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); + fspath = malloc(MNAMELEN, M_TEMP, M_WAITOK); + + /* + * vfs_mount() actually takes a kernel string for `type' and + * `path' now, so extract them. + */ + error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); + if (error == 0) + error = copyinstr(uap->path, fspath, MNAMELEN, NULL); + if (error == 0) + error = vfs_mount(td, fstype, fspath, uap->flags, uap->data); + free(fstype, M_TEMP); + free(fspath, M_TEMP); + return (error); +} + +/* + * vfs_mount(): actually attempt a filesystem mount. + * + * This routine is designed to be a "generic" entry point for routines + * that wish to mount a filesystem. All parameters except `fsdata' are + * pointers into kernel space. `fsdata' is currently still a pointer + * into userspace. + */ +int +vfs_mount(td, fstype, fspath, fsflags, fsdata) + struct thread *td; + const char *fstype; + char *fspath; + int fsflags; + void *fsdata; +{ + linker_file_t lf; + struct vnode *vp; + struct mount *mp; + struct vfsconf *vfsp; + int error, flag = 0, kern_flag = 0; + struct vattr va; + struct nameidata nd; + + /* + * Be ultra-paranoid about making sure the type and fspath + * variables will fit in our mp buffers, including the + * terminating NUL. + */ + if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) + return (ENAMETOOLONG); + + if (usermount == 0) { + error = suser(td); + if (error) + return (error); + } + /* + * Do not allow NFS export by non-root users. + */ + if (fsflags & MNT_EXPORTED) { + error = suser(td); + if (error) + return (error); + } + /* + * Silently enforce MNT_NOSUID and MNT_NODEV for non-root users. + */ + if (suser(td)) + fsflags |= MNT_NOSUID | MNT_NODEV; + /* + * Get vnode to be covered + */ + NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspath, td); + if ((error = namei(&nd)) != 0) + return (error); + NDFREE(&nd, NDF_ONLY_PNBUF); + vp = nd.ni_vp; + if (fsflags & MNT_UPDATE) { + if ((vp->v_vflag & VV_ROOT) == 0) { + vput(vp); + return (EINVAL); + } + mp = vp->v_mount; + flag = mp->mnt_flag; + kern_flag = mp->mnt_kern_flag; + /* + * We only allow the filesystem to be reloaded if it + * is currently mounted read-only. + */ + if ((fsflags & MNT_RELOAD) && + ((mp->mnt_flag & MNT_RDONLY) == 0)) { + vput(vp); + return (EOPNOTSUPP); /* Needs translation */ + } + /* + * Only root, or the user that did the original mount is + * permitted to update it. + */ + if (mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { + error = suser(td); + if (error) { + vput(vp); + return (error); + } + } + if (vfs_busy(mp, LK_NOWAIT, 0, td)) { + vput(vp); + return (EBUSY); + } + VI_LOCK(vp); + if ((vp->v_iflag & VI_MOUNT) != 0 || + vp->v_mountedhere != NULL) { + VI_UNLOCK(vp); + vfs_unbusy(mp, td); + vput(vp); + return (EBUSY); + } + vp->v_iflag |= VI_MOUNT; + VI_UNLOCK(vp); + mp->mnt_flag |= fsflags & + (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_SNAPSHOT); + VOP_UNLOCK(vp, 0, td); + goto update; + } + /* + * If the user is not root, ensure that they own the directory + * onto which we are attempting to mount. + */ + error = VOP_GETATTR(vp, &va, td->td_ucred, td); + if (error) { + vput(vp); + return (error); + } + if (va.va_uid != td->td_ucred->cr_uid) { + error = suser(td); + if (error) { + vput(vp); + return (error); + } + } + if ((error = vinvalbuf(vp, V_SAVE, td->td_ucred, td, 0, 0)) != 0) { + vput(vp); + return (error); + } + if (vp->v_type != VDIR) { + vput(vp); + return (ENOTDIR); + } + for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) + if (!strcmp(vfsp->vfc_name, fstype)) + break; + if (vfsp == NULL) { + /* Only load modules for root (very important!). */ + error = suser(td); + if (error) { + vput(vp); + return (error); + } + error = securelevel_gt(td->td_ucred, 0); + if (error) { + vput(vp); + return (error); + } + error = linker_load_module(NULL, fstype, NULL, NULL, &lf); + if (error || lf == NULL) { + vput(vp); + if (lf == NULL) + error = ENODEV; + return (error); + } + lf->userrefs++; + /* Look up again to see if the VFS was loaded. */ + for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) + if (!strcmp(vfsp->vfc_name, fstype)) + break; + if (vfsp == NULL) { + lf->userrefs--; + linker_file_unload(lf); + vput(vp); + return (ENODEV); + } + } + VI_LOCK(vp); + if ((vp->v_iflag & VI_MOUNT) != 0 || + vp->v_mountedhere != NULL) { + VI_UNLOCK(vp); + vput(vp); + return (EBUSY); + } + vp->v_iflag |= VI_MOUNT; + VI_UNLOCK(vp); + + /* + * Allocate and initialize the filesystem. + */ + mp = malloc(sizeof(struct mount), M_MOUNT, M_WAITOK | M_ZERO); + TAILQ_INIT(&mp->mnt_nvnodelist); + TAILQ_INIT(&mp->mnt_reservedvnlist); + mp->mnt_nvnodelistsize = 0; + lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, LK_NOPAUSE); + (void)vfs_busy(mp, LK_NOWAIT, 0, td); + mp->mnt_op = vfsp->vfc_vfsops; + mp->mnt_vfc = vfsp; + vfsp->vfc_refcount++; + mp->mnt_stat.f_type = vfsp->vfc_typenum; + mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK; + strlcpy(mp->mnt_stat.f_fstypename, fstype, MFSNAMELEN); + mp->mnt_vnodecovered = vp; + mp->mnt_cred = crdup(td->td_ucred); + mp->mnt_stat.f_owner = td->td_ucred->cr_uid; + strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); + mp->mnt_iosize_max = DFLTPHYS; +#ifdef MAC + mac_init_mount(mp); + mac_create_mount(td->td_ucred, mp); +#endif + VOP_UNLOCK(vp, 0, td); +update: + /* + * Check if the fs implements the old VFS_MOUNT() + * function, since the old system call was used. + */ + if (mp->mnt_op->vfs_mount == NULL) { + printf("%s doesn't support the old mount syscall\n", + mp->mnt_vfc->vfc_name); + VI_LOCK(vp); + vp->v_iflag &= ~VI_MOUNT; + VI_UNLOCK(vp); + if (mp->mnt_flag & MNT_UPDATE) + vfs_unbusy(mp, td); + else { + mp->mnt_vfc->vfc_refcount--; + vfs_unbusy(mp, td); +#ifdef MAC + mac_destroy_mount(mp); +#endif + crfree(mp->mnt_cred); + free(mp, M_MOUNT); + } + vrele(vp); + return (EOPNOTSUPP); + } + + /* + * Set the mount level flags. + */ + if (fsflags & MNT_RDONLY) + mp->mnt_flag |= MNT_RDONLY; + else if (mp->mnt_flag & MNT_RDONLY) + mp->mnt_kern_flag |= MNTK_WANTRDWR; + mp->mnt_flag &=~ MNT_UPDATEMASK; + mp->mnt_flag |= fsflags & (MNT_UPDATEMASK | MNT_FORCE); + /* + * Mount the filesystem. + * XXX The final recipients of VFS_MOUNT just overwrite the ndp they + * get. No freeing of cn_pnbuf. + */ + error = VFS_MOUNT(mp, fspath, fsdata, &nd, td); + if (mp->mnt_flag & MNT_UPDATE) { + if (mp->mnt_kern_flag & MNTK_WANTRDWR) + mp->mnt_flag &= ~MNT_RDONLY; + mp->mnt_flag &=~ + (MNT_UPDATE | MNT_RELOAD | MNT_FORCE | MNT_SNAPSHOT); + mp->mnt_kern_flag &=~ MNTK_WANTRDWR; + if (error) { + mp->mnt_flag = flag; + mp->mnt_kern_flag = kern_flag; + } + if ((mp->mnt_flag & MNT_RDONLY) == 0) { + if (mp->mnt_syncer == NULL) + error = vfs_allocate_syncvnode(mp); + } else { + if (mp->mnt_syncer != NULL) + vrele(mp->mnt_syncer); + mp->mnt_syncer = NULL; + } + vfs_unbusy(mp, td); + VI_LOCK(vp); + vp->v_iflag &= ~VI_MOUNT; + VI_UNLOCK(vp); + vrele(vp); + return (error); + } + vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); + /* + * Put the new filesystem on the mount list after root. + */ + cache_purge(vp); + if (!error) { + struct vnode *newdp; + + VI_LOCK(vp); + vp->v_iflag &= ~VI_MOUNT; + VI_UNLOCK(vp); + vp->v_mountedhere = mp; + mtx_lock(&mountlist_mtx); + TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); + mtx_unlock(&mountlist_mtx); + if (VFS_ROOT(mp, &newdp)) + panic("mount: lost mount"); + checkdirs(vp, newdp); + vput(newdp); + VOP_UNLOCK(vp, 0, td); + if ((mp->mnt_flag & MNT_RDONLY) == 0) + error = vfs_allocate_syncvnode(mp); + vfs_unbusy(mp, td); + if ((error = VFS_START(mp, 0, td)) != 0) + vrele(vp); + } else { + VI_LOCK(vp); + vp->v_iflag &= ~VI_MOUNT; + VI_UNLOCK(vp); + mp->mnt_vfc->vfc_refcount--; + vfs_unbusy(mp, td); +#ifdef MAC + mac_destroy_mount(mp); +#endif + crfree(mp->mnt_cred); + free(mp, M_MOUNT); + vput(vp); + } + return (error); +} + +/* + * Scan all active processes to see if any of them have a current + * or root directory of `olddp'. If so, replace them with the new + * mount point. + */ +static void +checkdirs(olddp, newdp) + struct vnode *olddp, *newdp; +{ + struct filedesc *fdp; + struct proc *p; + int nrele; + + if (vrefcnt(olddp) == 1) + return; + sx_slock(&allproc_lock); + LIST_FOREACH(p, &allproc, p_list) { + mtx_lock(&fdesc_mtx); + fdp = p->p_fd; + if (fdp == NULL) { + mtx_unlock(&fdesc_mtx); + continue; + } + nrele = 0; + FILEDESC_LOCK(fdp); + if (fdp->fd_cdir == olddp) { + VREF(newdp); + fdp->fd_cdir = newdp; + nrele++; + } + if (fdp->fd_rdir == olddp) { + VREF(newdp); + fdp->fd_rdir = newdp; + nrele++; + } + FILEDESC_UNLOCK(fdp); + mtx_unlock(&fdesc_mtx); + while (nrele--) + vrele(olddp); + } + sx_sunlock(&allproc_lock); + if (rootvnode == olddp) { + vrele(rootvnode); + VREF(newdp); + rootvnode = newdp; + } +} + +/* + * Unmount a filesystem. + * + * Note: unmount takes a path to the vnode mounted on as argument, + * not special file (as before). + */ +#ifndef _SYS_SYSPROTO_H_ +struct unmount_args { + char *path; + int flags; +}; +#endif +/* ARGSUSED */ +int +unmount(td, uap) + struct thread *td; + register struct unmount_args /* { + char *path; + int flags; + } */ *uap; +{ + struct mount *mp; + char *pathbuf; + int error, id0, id1; + + pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); + error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); + if (error) { + free(pathbuf, M_TEMP); + return (error); + } + if (uap->flags & MNT_BYFSID) { + /* Decode the filesystem ID. */ + if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { + free(pathbuf, M_TEMP); + return (EINVAL); + } + + mtx_lock(&mountlist_mtx); + TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) + if (mp->mnt_stat.f_fsid.val[0] == id0 && + mp->mnt_stat.f_fsid.val[1] == id1) + break; + mtx_unlock(&mountlist_mtx); + } else { + mtx_lock(&mountlist_mtx); + TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) + if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) + break; + mtx_unlock(&mountlist_mtx); + } + free(pathbuf, M_TEMP); + if (mp == NULL) + return (ENOENT); + + /* + * Only root, or the user that did the original mount is + * permitted to unmount this filesystem. + */ + if (mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { + error = suser(td); + if (error) + return (error); + } + + /* + * Don't allow unmounting the root filesystem. + */ + if (mp->mnt_flag & MNT_ROOTFS) + return (EINVAL); + return (dounmount(mp, uap->flags, td)); +} + +/* + * Do the actual filesystem unmount. + */ +int +dounmount(mp, flags, td) + struct mount *mp; + int flags; + struct thread *td; +{ + struct vnode *coveredvp, *fsrootvp; + int error; + int async_flag; + + mtx_lock(&mountlist_mtx); + if (mp->mnt_kern_flag & MNTK_UNMOUNT) { + mtx_unlock(&mountlist_mtx); + return (EBUSY); + } + mp->mnt_kern_flag |= MNTK_UNMOUNT; + /* Allow filesystems to detect that a forced unmount is in progress. */ + if (flags & MNT_FORCE) + mp->mnt_kern_flag |= MNTK_UNMOUNTF; + error = lockmgr(&mp->mnt_lock, LK_DRAIN | LK_INTERLOCK | + ((flags & MNT_FORCE) ? 0 : LK_NOWAIT), &mountlist_mtx, td); + if (error) { + mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); + if (mp->mnt_kern_flag & MNTK_MWAIT) + wakeup(mp); + return (error); + } + vn_start_write(NULL, &mp, V_WAIT); + + if (mp->mnt_flag & MNT_EXPUBLIC) + vfs_setpublicfs(NULL, NULL, NULL); + + vfs_msync(mp, MNT_WAIT); + async_flag = mp->mnt_flag & MNT_ASYNC; + mp->mnt_flag &=~ MNT_ASYNC; + cache_purgevfs(mp); /* remove cache entries for this file sys */ + if (mp->mnt_syncer != NULL) + vrele(mp->mnt_syncer); + /* Move process cdir/rdir refs on fs root to underlying vnode. */ + if (VFS_ROOT(mp, &fsrootvp) == 0) { + if (mp->mnt_vnodecovered != NULL) + checkdirs(fsrootvp, mp->mnt_vnodecovered); + if (fsrootvp == rootvnode) { + vrele(rootvnode); + rootvnode = NULL; + } + vput(fsrootvp); + } + if (((mp->mnt_flag & MNT_RDONLY) || + (error = VFS_SYNC(mp, MNT_WAIT, td->td_ucred, td)) == 0) || + (flags & MNT_FORCE)) { + error = VFS_UNMOUNT(mp, flags, td); + } + vn_finished_write(mp); + if (error) { + /* Undo cdir/rdir and rootvnode changes made above. */ + if (VFS_ROOT(mp, &fsrootvp) == 0) { + if (mp->mnt_vnodecovered != NULL) + checkdirs(mp->mnt_vnodecovered, fsrootvp); + if (rootvnode == NULL) { + rootvnode = fsrootvp; + vref(rootvnode); + } + vput(fsrootvp); + } + if ((mp->mnt_flag & MNT_RDONLY) == 0 && mp->mnt_syncer == NULL) + (void) vfs_allocate_syncvnode(mp); + mtx_lock(&mountlist_mtx); + mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); + mp->mnt_flag |= async_flag; + lockmgr(&mp->mnt_lock, LK_RELEASE | LK_INTERLOCK, + &mountlist_mtx, td); + if (mp->mnt_kern_flag & MNTK_MWAIT) + wakeup(mp); + return (error); + } + crfree(mp->mnt_cred); + mtx_lock(&mountlist_mtx); + TAILQ_REMOVE(&mountlist, mp, mnt_list); + if ((coveredvp = mp->mnt_vnodecovered) != NULL) + coveredvp->v_mountedhere = NULL; + mp->mnt_vfc->vfc_refcount--; + if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) + panic("unmount: dangling vnode"); + lockmgr(&mp->mnt_lock, LK_RELEASE | LK_INTERLOCK, &mountlist_mtx, td); + lockdestroy(&mp->mnt_lock); + if (coveredvp != NULL) + vrele(coveredvp); + if (mp->mnt_kern_flag & MNTK_MWAIT) + wakeup(mp); +#ifdef MAC + mac_destroy_mount(mp); +#endif + if (mp->mnt_op->vfs_mount == NULL) + vfs_freeopts(mp->mnt_opt); + free(mp, M_MOUNT); + return (0); +} + +/* + * Lookup a filesystem type, and if found allocate and initialize + * a mount structure for it. + * + * Devname is usually updated by mount(8) after booting. + */ +int +vfs_rootmountalloc(fstypename, devname, mpp) + char *fstypename; + char *devname; + struct mount **mpp; +{ + struct thread *td = curthread; /* XXX */ + struct vfsconf *vfsp; + struct mount *mp; + + if (fstypename == NULL) + return (ENODEV); + for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) + if (!strcmp(vfsp->vfc_name, fstypename)) + break; + if (vfsp == NULL) + return (ENODEV); + mp = malloc((u_long)sizeof(struct mount), M_MOUNT, M_WAITOK | M_ZERO); + lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, LK_NOPAUSE); + (void)vfs_busy(mp, LK_NOWAIT, 0, td); + TAILQ_INIT(&mp->mnt_nvnodelist); + TAILQ_INIT(&mp->mnt_reservedvnlist); + mp->mnt_nvnodelistsize = 0; + mp->mnt_vfc = vfsp; + mp->mnt_op = vfsp->vfc_vfsops; + mp->mnt_flag = MNT_RDONLY; + mp->mnt_vnodecovered = NULLVP; + mp->mnt_cred = crdup(td->td_ucred); + vfsp->vfc_refcount++; + mp->mnt_iosize_max = DFLTPHYS; + mp->mnt_stat.f_type = vfsp->vfc_typenum; + mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK; + strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); + mp->mnt_stat.f_mntonname[0] = '/'; + mp->mnt_stat.f_mntonname[1] = 0; + strlcpy(mp->mnt_stat.f_mntfromname, devname, MNAMELEN); +#ifdef MAC + mac_init_mount(mp); + mac_create_mount(td->td_ucred, mp); +#endif + *mpp = mp; + return (0); +} + +/* + * Find and mount the root filesystem + */ +void +vfs_mountroot(void) +{ + char *cp; + int i, error; + + g_waitidle(); + + /* + * The root filesystem information is compiled in, and we are + * booted with instructions to use it. + */ +#ifdef ROOTDEVNAME + if ((boothowto & RB_DFLTROOT) && + !vfs_mountroot_try(ROOTDEVNAME)) + return; +#endif + /* + * We are booted with instructions to prompt for the root filesystem, + * or to use the compiled-in default when it doesn't exist. + */ + if (boothowto & (RB_DFLTROOT | RB_ASKNAME)) { + if (!vfs_mountroot_ask()) + return; + } + + /* + * We've been given the generic "use CDROM as root" flag. This is + * necessary because one media may be used in many different + * devices, so we need to search for them. + */ + if (boothowto & RB_CDROM) { + for (i = 0; cdrom_rootdevnames[i] != NULL; i++) { + if (!vfs_mountroot_try(cdrom_rootdevnames[i])) + return; + } + } + + /* + * Try to use the value read by the loader from /etc/fstab, or + * supplied via some other means. This is the preferred + * mechanism. + */ + if ((cp = getenv("vfs.root.mountfrom")) != NULL) { + error = vfs_mountroot_try(cp); + freeenv(cp); + if (!error) + return; + } + + /* + * Try values that may have been computed by the machine-dependant + * legacy code. + */ + if (!vfs_mountroot_try(rootdevnames[0])) + return; + if (!vfs_mountroot_try(rootdevnames[1])) + return; + + /* + * If we have a compiled-in default, and haven't already tried it, try + * it now. + */ +#ifdef ROOTDEVNAME + if (!(boothowto & RB_DFLTROOT)) + if (!vfs_mountroot_try(ROOTDEVNAME)) + return; +#endif + + /* + * Everything so far has failed, prompt on the console if we haven't + * already tried that. + */ + if (!(boothowto & (RB_DFLTROOT | RB_ASKNAME)) && !vfs_mountroot_ask()) + return; + panic("Root mount failed, startup aborted."); +} + +/* + * Mount (mountfrom) as the root filesystem. + */ +static int +vfs_mountroot_try(char *mountfrom) +{ + struct mount *mp; + char *vfsname, *path; + const char *devname; + int error; + char patt[32]; + int s; + + vfsname = NULL; + path = NULL; + mp = NULL; + error = EINVAL; + + if (mountfrom == NULL) + return(error); /* don't complain */ + + s = splcam(); /* Overkill, but annoying without it */ + printf("Mounting root from %s\n", mountfrom); + splx(s); + + /* parse vfs name and path */ + vfsname = malloc(MFSNAMELEN, M_MOUNT, M_WAITOK); + path = malloc(MNAMELEN, M_MOUNT, M_WAITOK); + vfsname[0] = path[0] = 0; + sprintf(patt, "%%%d[a-z0-9]:%%%zds", MFSNAMELEN, MNAMELEN); + if (sscanf(mountfrom, patt, vfsname, path) < 1) + goto done; + + /* allocate a root mount */ + error = vfs_rootmountalloc(vfsname, path[0] != 0 ? path : ROOTNAME, + &mp); + if (error != 0) { + printf("Can't allocate root mount for filesystem '%s': %d\n", + vfsname, error); + goto done; + } + mp->mnt_flag |= MNT_ROOTFS; + + /* do our best to set rootdev */ + if ((path[0] != 0) && setrootbyname(path)) + printf("setrootbyname failed\n"); + + /* If the root device is a type "memory disk", mount RW */ + if (rootdev != NODEV && devsw(rootdev) != NULL) { + devname = devtoname(rootdev); + if (devname[0] == 'm' && devname[1] == 'd') + mp->mnt_flag &= ~MNT_RDONLY; + } + + /* + * Set the mount path to be something useful, because the + * filesystem code isn't responsible now for initialising + * f_mntonname unless they want to override the default + * (which is `path'.) + */ + strlcpy(mp->mnt_stat.f_mntonname, "/", MNAMELEN); + + error = VFS_MOUNT(mp, NULL, NULL, NULL, curthread); + +done: + if (vfsname != NULL) + free(vfsname, M_MOUNT); + if (path != NULL) + free(path, M_MOUNT); + if (error != 0) { + if (mp != NULL) { + vfs_unbusy(mp, curthread); +#ifdef MAC + mac_destroy_mount(mp); +#endif + crfree(mp->mnt_cred); + free(mp, M_MOUNT); + } + printf("Root mount failed: %d\n", error); + } else { + + /* register with list of mounted filesystems */ + mtx_lock(&mountlist_mtx); + TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); + mtx_unlock(&mountlist_mtx); + + /* sanity check system clock against root fs timestamp */ + inittodr(mp->mnt_time); + vfs_unbusy(mp, curthread); + error = VFS_START(mp, 0, curthread); + } + return(error); +} + +/* + * Spin prompting on the console for a suitable root filesystem + */ +static int +vfs_mountroot_ask(void) +{ + char name[128]; + + for(;;) { + printf("\nManual root filesystem specification:\n"); + printf(" <fstype>:<device> Mount <device> using filesystem <fstype>\n"); +#if defined(__i386__) || defined(__ia64__) + printf(" eg. ufs:da0s1a\n"); +#else + printf(" eg. ufs:/dev/da0a\n"); +#endif + printf(" ? List valid disk boot devices\n"); + printf(" <empty line> Abort manual input\n"); + printf("\nmountroot> "); + gets(name); + if (name[0] == 0) + return(1); + if (name[0] == '?') { + printf("\nList of GEOM managed disk devices:\n "); + g_dev_print(); + continue; + } + if (!vfs_mountroot_try(name)) + return(0); + } +} + +/* + * Local helper function for vfs_mountroot_ask. + */ +static void +gets(char *cp) +{ + char *lp; + int c; + + lp = cp; + for (;;) { + printf("%c", c = cngetc() & 0177); + switch (c) { + case -1: + case '\n': + case '\r': + *lp++ = '\0'; + return; + case '\b': + case '\177': + if (lp > cp) { + printf(" \b"); + lp--; + } + continue; + case '#': + lp--; + if (lp < cp) + lp = cp; + continue; + case '@': + case 'u' & 037: + lp = cp; + printf("%c", '\n'); + continue; + default: + *lp++ = c; + } + } +} + +/* + * Convert a given name to the dev_t of the disk-like device + * it refers to. + */ +dev_t +getdiskbyname(char *name) { + char *cp; + dev_t dev; + + cp = name; + if (!bcmp(cp, "/dev/", 5)) + cp += 5; + + dev = NODEV; + EVENTHANDLER_INVOKE(dev_clone, cp, strlen(cp), &dev); + return (dev); +} + +/* + * Set rootdev to match (name), given that we expect it to + * refer to a disk-like device. + */ +static int +setrootbyname(char *name) +{ + dev_t diskdev; + + diskdev = getdiskbyname(name); + if (diskdev != NODEV) { + rootdev = diskdev; + return (0); + } + + return (1); +} + +/* Show the dev_t for a disk specified by name */ +#ifdef DDB +DB_SHOW_COMMAND(disk, db_getdiskbyname) +{ + dev_t dev; + + if (modif[0] == '\0') { + db_error("usage: show disk/devicename"); + return; + } + dev = getdiskbyname(modif); + if (dev != NODEV) + db_printf("dev_t = %p\n", dev); + else + db_printf("No disk device matched.\n"); +} +#endif + +/* + * Get a mount option by its name. + * + * Return 0 if the option was found, ENOENT otherwise. + * If len is non-NULL it will be filled with the length + * of the option. If buf is non-NULL, it will be filled + * with the address of the option. + */ +int +vfs_getopt(opts, name, buf, len) + struct vfsoptlist *opts; + const char *name; + void **buf; + int *len; +{ + struct vfsopt *opt; + + KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); + + TAILQ_FOREACH(opt, opts, link) { + if (strcmp(name, opt->name) == 0) { + if (len != NULL) + *len = opt->len; + if (buf != NULL) + *buf = opt->value; + return (0); + } + } + return (ENOENT); +} + +/* + * Find and copy a mount option. + * + * The size of the buffer has to be specified + * in len, if it is not the same length as the + * mount option, EINVAL is returned. + * Returns ENOENT if the option is not found. + */ +int +vfs_copyopt(opts, name, dest, len) + struct vfsoptlist *opts; + const char *name; + void *dest; + int len; +{ + struct vfsopt *opt; + + KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); + + TAILQ_FOREACH(opt, opts, link) { + if (strcmp(name, opt->name) == 0) { + if (len != opt->len) + return (EINVAL); + bcopy(opt->value, dest, opt->len); + return (0); + } + } + return (ENOENT); +} |
