/*
* Convert from automount node to file handle.
*/
void
mp_to_fh(am_node *mp, am_nfs_fh *fhp)
{
u_int pathlen;
struct am_fh *fp = (struct am_fh *) fhp;
memset((char *) fhp, 0, sizeof(am_nfs_fh));
/* Store the generation number */
fp->fhh_gen = mp->am_gen;
pathlen = strlen(mp->am_path);
if (pathlen <= sizeof(*fhp) - sizeof(fp->fhh_gen)) {
/* dlog("mp_to_fh: new filehandle: %s", mp->am_path); */
/*
* Because fhp is treated as a filehandle we use memcpy instead of
* xstrlcpy.
*/
memcpy(fp->u.fhh_path, mp->am_path, pathlen); /* making a filehandle */
} else {
/*
* Take the process id
*/
fp->u.s.fhh_pid = get_server_pid();
/*
* ... the map number
*/
fp->u.s.fhh_id = mp->am_mapno;
/*
* ... and the generation number (previously stored)
* to make a "unique" triple that will never
* be reallocated except across reboots (which doesn't matter)
* or if we are unlucky enough to be given the same
* pid as a previous amd (very unlikely).
*/
/* dlog("mp_to_fh: old filehandle: %d", fp->u.s.fhh_id); */
}
}
/*
* Convert from file handle to automount node.
*/
static am_node *
fh_to_mp3(am_nfs_fh *fhp, int *rp, int vop)
{
struct am_fh *fp = (struct am_fh *) fhp;
am_node *ap = NULL;
if (fp->u.s.fhh_type != 0) {
/* New filehandle type */
int len = sizeof(*fhp) - sizeof(fp->fhh_gen);
char *path = xmalloc(len+1);
/*
* Because fhp is treated as a filehandle we use memcpy
* instead of xstrlcpy.
*/
memcpy(path, (char *) fp->u.fhh_path, len);
path[len] = '\0';
/* dlog("fh_to_mp3: new filehandle: %s", path); */
ap = path_to_exported_ap(path);
XFREE(path);
} else {
/* dlog("fh_to_mp3: old filehandle: %d", fp->u.s.fhh_id); */
/*
* Check process id matches
* If it doesn't then it is probably
* from an old kernel-cached filehandle
* which is now out of date.
*/
if (fp->u.s.fhh_pid != get_server_pid()) {
dlog("fh_to_mp3: wrong pid %ld != my pid %ld",
(long) fp->u.s.fhh_pid, get_server_pid());
goto drop;
}
/*
* Get hold of the supposed mount node
*/
ap = get_exported_ap(fp->u.s.fhh_id);
}
/*
* Check the generation number in the node
* matches the one from the kernel. If not
* then the old node has been timed out and
* a new one allocated.
*/
if (ap != NULL && ap->am_gen != fp->fhh_gen)
ap = NULL;
/*
* If it doesn't exists then drop the request
*/
if (!ap)
goto drop;
#if 0
/*
* If the node is hung then locate a new node
* for it. This implements the replicated filesystem
* retries.
*/
if (ap->am_al->al_mnt && FSRV_ISDOWN(ap->am_al->al_mnt->mf_server) && ap->am_parent) {
int error;
am_node *orig_ap = ap;
dlog("fh_to_mp3: %s (%s) is hung: lookup alternative file server",
orig_ap->am_path, orig_ap->am_al->al_mnt->mf_info);
/*
* Update modify time of parent node.
* With any luck the kernel will re-stat
* the child node and get new information.
*/
clocktime(&orig_ap->am_fattr.na_mtime);
/*
* Call the parent's lookup routine for an object
* with the same name. This may return -1 in error
* if a mount is in progress. In any case, if no
* mount node is returned the error code is propagated
* to the caller.
*/
if (vop == VLOOK_CREATE) {
ap = orig_ap->am_parent->am_al->al_mnt->mf_ops->lookup_child(orig_ap->am_parent, orig_ap->am_name, &error, vop);
if (ap && error < 0)
ap = orig_ap->am_parent->am_al->al_mnt->mf_ops->mount_child(ap, &error);
} else {
ap = NULL;
error = ESTALE;
}
if (ap == 0) {
if (error < 0 && amd_state == Finishing)
error = ENOENT;
*rp = error;
return 0;
}
/*
* Update last access to original node. This
* avoids timing it out and so sending ESTALE
* back to the kernel.
* XXX - Not sure we need this anymore (jsp, 90/10/6).
*/
new_ttl(orig_ap);
}
#endif /* 0 */
/*
* Disallow references to objects being unmounted, unless
* they are automount points.
*/
if (ap->am_al->al_mnt && (ap->am_al->al_mnt->mf_flags & MFF_UNMOUNTING) &&
!(ap->am_flags & AMF_ROOT)) {
if (amd_state == Finishing)
*rp = ENOENT;
else
*rp = -1;
return 0;
}
new_ttl(ap);
drop:
if (!ap || !ap->am_al->al_mnt) {
/*
* If we are shutting down then it is likely
* that this node has disappeared because of
* a fast timeout. To avoid things thrashing
* just pretend it doesn't exist at all. If
* ESTALE is returned, some NFS clients just
* keep retrying (stupid or what - if it's
* stale now, what's it going to be in 5 minutes?)
*/
if (amd_state == Finishing)
*rp = ENOENT;
else {
*rp = ESTALE;
amd_stats.d_stale++;
}
}
return ap;
}
/*
* Mount an automounter directory.
* The automounter is connected into the system
* as a user-level NFS server. amfs_mount constructs
* the necessary NFS parameters to be given to the
* kernel so that it will talk back to us.
*
* NOTE: automounter mounts in themselves are using NFS Version 2 (UDP).
*
* NEW: on certain systems, mounting can be done using the
* kernel-level automount (autofs) support. In that case,
* we don't need NFS at all here.
*/
int
amfs_mount(am_node *mp, mntfs *mf, char *opts)
{
char fs_hostname[MAXHOSTNAMELEN + MAXPATHLEN + 1];
int retry, error = 0, genflags;
int on_autofs = mf->mf_flags & MFF_ON_AUTOFS;
char *dir = mf->mf_mount;
mntent_t mnt;
MTYPE_TYPE type;
int forced_unmount = 0; /* are we using forced unmounts? */
u_long nfs_version = get_nfs_dispatcher_version(nfs_dispatcher);
memset(&mnt, 0, sizeof(mnt));
mnt.mnt_dir = dir;
mnt.mnt_fsname = pid_fsname;
mnt.mnt_opts = opts;
#ifdef HAVE_FS_AUTOFS
if (mf->mf_flags & MFF_IS_AUTOFS) {
type = MOUNT_TYPE_AUTOFS;
/*
* Make sure that amd's top-level autofs mounts are hidden by default
* from df.
* XXX: It works ok on Linux, might not work on other systems.
*/
mnt.mnt_type = "autofs";
} else
#endif /* HAVE_FS_AUTOFS */
{
type = MOUNT_TYPE_NFS;
/*
* Make sure that amd's top-level NFS mounts are hidden by default
* from df.
* If they don't appear to support the either the "ignore" mnttab
* option entry, or the "auto" one, set the mount type to "nfs".
*/
mnt.mnt_type = HIDE_MOUNT_TYPE;
}
retry = hasmntval(&mnt, MNTTAB_OPT_RETRY);
if (retry <= 0)
retry = 2; /* XXX: default to 2 retries */
/*
* SET MOUNT ARGS
*/
/*
* Make a ``hostname'' string for the kernel
*/
xsnprintf(fs_hostname, sizeof(fs_hostname), "pid%ld@%s:%s",
get_server_pid(), am_get_hostname(), dir);
/*
* Most kernels have a name length restriction (64 bytes)...
*/
if (strlen(fs_hostname) >= MAXHOSTNAMELEN)
xstrlcpy(fs_hostname + MAXHOSTNAMELEN - 3, "..",
sizeof(fs_hostname) - MAXHOSTNAMELEN + 3);
#ifdef HOSTNAMESZ
/*
* ... and some of these restrictions are 32 bytes (HOSTNAMESZ)
* If you need to get the definition for HOSTNAMESZ found, you may
* add the proper header file to the conf/nfs_prot/nfs_prot_*.h file.
*/
if (strlen(fs_hostname) >= HOSTNAMESZ)
xstrlcpy(fs_hostname + HOSTNAMESZ - 3, "..",
sizeof(fs_hostname) - HOSTNAMESZ + 3);
#endif /* HOSTNAMESZ */
/*
* Finally we can compute the mount genflags set above,
* and add any automounter specific flags.
*/
genflags = compute_mount_flags(&mnt);
#ifdef HAVE_FS_AUTOFS
if (on_autofs)
genflags |= autofs_compute_mount_flags(&mnt);
#endif /* HAVE_FS_AUTOFS */
genflags |= compute_automounter_mount_flags(&mnt);
again:
if (!(mf->mf_flags & MFF_IS_AUTOFS)) {
nfs_args_t nfs_args;
am_nfs_handle_t *fhp, anh;
#ifndef HAVE_TRANSPORT_TYPE_TLI
u_short port;
struct sockaddr_in sin;
#endif /* not HAVE_TRANSPORT_TYPE_TLI */
/*
* get fhandle of remote path for automount point
*/
fhp = get_root_nfs_fh(dir, &anh);
if (!fhp) {
plog(XLOG_FATAL, "Can't find root file handle for %s", dir);
return EINVAL;
}
#ifndef HAVE_TRANSPORT_TYPE_TLI
/*
* Create sockaddr to point to the local machine.
*/
memset(&sin, 0, sizeof(sin));
/* as per POSIX, sin_len need not be set (used internally by kernel) */
sin.sin_family = AF_INET;
sin.sin_addr = myipaddr;
port = hasmntval(&mnt, MNTTAB_OPT_PORT);
if (port) {
sin.sin_port = htons(port);
} else {
plog(XLOG_ERROR, "no port number specified for %s", dir);
return EINVAL;
}
#endif /* not HAVE_TRANSPORT_TYPE_TLI */
/* setup the many fields and flags within nfs_args */
#ifdef HAVE_TRANSPORT_TYPE_TLI
compute_nfs_args(&nfs_args,
&mnt,
genflags,
nfsncp,
NULL, /* remote host IP addr is set below */
nfs_version,
"udp",
fhp,
fs_hostname,
pid_fsname);
/*
* IMPORTANT: set the correct IP address AFTERWARDS. It cannot
* be done using the normal mechanism of compute_nfs_args(), because
* that one will allocate a new address and use NFS_SA_DREF() to copy
* parts to it, while assuming that the ip_addr passed is always
* a "struct sockaddr_in". That assumption is incorrect on TLI systems,
* because they define a special macro HOST_SELF which is DIFFERENT
* than localhost (127.0.0.1)!
*/
nfs_args.addr = &nfsxprt->xp_ltaddr;
#else /* not HAVE_TRANSPORT_TYPE_TLI */
compute_nfs_args(&nfs_args,
&mnt,
genflags,
NULL,
&sin,
nfs_version,
"udp",
fhp,
fs_hostname,
pid_fsname);
#endif /* not HAVE_TRANSPORT_TYPE_TLI */
/*************************************************************************
* NOTE: while compute_nfs_args() works ok for regular NFS mounts *
* the toplvl one is not quite regular, and so some options must be *
* corrected by hand more carefully, *after* compute_nfs_args() runs. *
*************************************************************************/
compute_automounter_nfs_args(&nfs_args, &mnt);
if (amuDebug(D_TRACE)) {
print_nfs_args(&nfs_args, 0);
plog(XLOG_DEBUG, "Generic mount flags 0x%x", genflags);
}
/* This is it! Here we try to mount amd on its mount points */
error = mount_fs(&mnt, genflags, (caddr_t) &nfs_args,
retry, type, 0, NULL, mnttab_file_name, on_autofs);
#ifdef HAVE_TRANSPORT_TYPE_TLI
free_knetconfig(nfs_args.knconf);
/*
* local automounter mounts do not allocate a special address, so
* no need to XFREE(nfs_args.addr) under TLI.
*/
#endif /* HAVE_TRANSPORT_TYPE_TLI */
#ifdef HAVE_FS_AUTOFS
} else {
/* This is it! Here we try to mount amd on its mount points */
error = mount_fs(&mnt, genflags, (caddr_t) mp->am_autofs_fh,
retry, type, 0, NULL, mnttab_file_name, on_autofs);
#endif /* HAVE_FS_AUTOFS */
}
if (error == 0 || forced_unmount)
return error;
/*
* If user wants forced/lazy unmount semantics, then try it iff the
* current mount failed with EIO or ESTALE.
*/
if (gopt.flags & CFM_FORCED_UNMOUNTS) {
switch (errno) {
case ESTALE:
case EIO:
forced_unmount = errno;
plog(XLOG_WARNING, "Mount %s failed (%m); force unmount.", mp->am_path);
if ((error = UMOUNT_FS(mp->am_path, mnttab_file_name,
AMU_UMOUNT_FORCE | AMU_UMOUNT_DETACH)) < 0) {
plog(XLOG_WARNING, "Forced umount %s failed: %m.", mp->am_path);
errno = forced_unmount;
} else
goto again;
default:
break;
}
}
return error;
}
