projects / unix-history / blob
? search:
summary | tags | clone url | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
from Jan Pendry
[unix-history] / usr / src / usr.sbin / amd / amd / nfs_ops.c
/*
* $Id: nfs_ops.c,v 5.2 90/06/23 22:19:45 jsp Rel $
*
* Copyright (c) 1990 Jan-Simon Pendry
* Copyright (c) 1990 Imperial College of Science, Technology & Medicine
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Jan-Simon Pendry at Imperial College, London.
*
* %sccs.include.redist.c%
*
* @(#)nfs_ops.c 5.1 (Berkeley) %G%
*/
#include "am.h"
#ifdef HAS_NFS
#define NFS
#define NFSCLIENT
#ifdef NFS_3
typedef nfs_fh fhandle_t;
#endif /* NFS_3 */
#ifdef NFS_HDR
#include NFS_HDR
#endif /* NFS_HDR */
#include <sys/mount.h>
#include "mount.h"
/*
* Network file system
*/
/*
* Convert from nfsstat to UN*X error code
*/
#define unx_error(e) ((int)(e))
/*
* The NFS layer maintains a cache of file handles.
* This is *fundamental* to the implementation and
* also allows quick remounting when a filesystem
* is accessed soon after timing out.
*
* The NFS server layer knows to flush this cache
* when a server goes down so avoiding stale handles.
*
* Each cache entry keeps a hard reference to
* the corresponding server. This ensures that
* the server keepalive information is maintained.
*
* The copy of the sockaddr_in here is taken so
* that the port can be twiddled to talk to mountd
* instead of portmap or the NFS server as used
* elsewhere.
* The port# is flushed if a server goes down.
* The IP address is never flushed - we assume
* that the address of a mounted machine never
* changes. If it does, then you have other
* problems...
*/
typedef struct fh_cache fh_cache;
struct fh_cache {
qelem fh_q; /* List header */
voidp fh_wchan; /* Wait channel */
int fh_error; /* Valid data? */
int fh_id; /* Unique id */
int fh_cid; /* Callout id */
struct fhstatus fh_handle; /* Handle on filesystem */
struct sockaddr_in fh_sin; /* Address of mountd */
fserver *fh_fs; /* Server holding filesystem */
char *fh_path; /* Filesystem on host */
};
/*
* FH_TTL is the time a file handle will remain in the cache since
* last being used. If the file handle becomes invalid, then it
* will be flushed anyway.
*/
#define FH_TTL (5 * 60) /* five minutes */
#define FH_TTL_ERROR (30) /* 30 seconds */
static int fh_id = 0;
#define FHID_ALLOC() (++fh_id)
extern qelem fh_head;
qelem fh_head = { &fh_head, &fh_head };
static int call_mountd P((fh_cache*, unsigned long, fwd_fun, voidp));
AUTH *nfs_auth;
static fh_cache *find_nfs_fhandle_cache P((voidp idv, int done));
static fh_cache *find_nfs_fhandle_cache(idv, done)
voidp idv;
int done;
{
fh_cache *fp, *fp2 = 0;
int id = (int) idv;
ITER(fp, fh_cache, &fh_head) {
if (fp->fh_id == id) {
fp2 = fp;
break;
}
}
#ifdef DEBUG
if (fp2) {
dlog("fh cache gives fp %#x, fs %s", fp2, fp2->fh_path);
} else {
dlog("fh cache search failed");
}
#endif /* DEBUG */
if (fp2 && !done) {
fp2->fh_error = ETIMEDOUT;
return 0;
}
return fp2;
}
/*
* Called when a filehandle appears
*/
static void got_nfs_fh P((voidp pkt, int len, struct sockaddr_in *sa,
struct sockaddr_in *ia, voidp idv, int done));
static void got_nfs_fh(pkt, len, sa, ia, idv, done)
voidp pkt;
int len;
struct sockaddr_in *sa, *ia;
voidp idv;
int done;
{
fh_cache *fp = find_nfs_fhandle_cache(idv, done);
if (fp) {
fp->fh_error = pickup_rpc_reply(pkt, len, (voidp) &fp->fh_handle, xdr_fhstatus);
if (!fp->fh_error) {
#ifdef DEBUG
dlog("got filehandle for %s:%s", fp->fh_fs->fs_host, fp->fh_path);
#endif /* DEBUG */
/*
* Wakeup anything sleeping on this filehandle
*/
if (fp->fh_wchan) {
#ifdef DEBUG
dlog("Calling wakeup on %#x", fp->fh_wchan);
#endif /* DEBUG */
wakeup(fp->fh_wchan);
}
}
}
}
void flush_nfs_fhandle_cache P((fserver *fs));
void flush_nfs_fhandle_cache(fs)
fserver *fs;
{
fh_cache *fp;
ITER(fp, fh_cache, &fh_head) {
if (fp->fh_fs == fs) {
fp->fh_sin.sin_port = (u_short) 0;
fp->fh_error = -1;
}
}
}
static void discard_fh P((fh_cache *fp));
static void discard_fh(fp)
fh_cache *fp;
{
rem_que(&fp->fh_q);
#ifdef DEBUG
dlog("Discarding filehandle for %s:%s", fp->fh_fs->fs_host, fp->fh_path);
#endif /* DEBUG */
free_srvr(fp->fh_fs);
free((voidp) fp->fh_path);
free((voidp) fp);
}
/*
* Determine the file handle for a node
*/
static int prime_nfs_fhandle_cache P((char *path, fserver *fs, struct fhstatus *fhbuf, voidp wchan));
static int prime_nfs_fhandle_cache(path, fs, fhbuf, wchan)
char *path;
fserver *fs;
struct fhstatus *fhbuf;
voidp wchan;
{
fh_cache *fp, *fp_save = 0;
int error;
int reuse_id = FALSE;
#ifdef DEBUG
dlog("Searching cache for %s:%s", fs->fs_host, path);
#endif /* DEBUG */
/*
* First search the cache
*/
ITER(fp, fh_cache, &fh_head) {
if (fs == fp->fh_fs && strcmp(path, fp->fh_path) == 0) {
switch (fp->fh_error) {
case 0:
error = fp->fh_error = unx_error(fp->fh_handle.fhs_status);
if (error == 0) {
if (fhbuf)
bcopy((voidp) &fp->fh_handle, (voidp) fhbuf,
sizeof(fp->fh_handle));
if (fp->fh_cid)
untimeout(fp->fh_cid);
fp->fh_cid = timeout(FH_TTL, discard_fh, (voidp) fp);
} else if (error == EACCES) {
/*
* Now decode the file handle return code.
*/
plog(XLOG_INFO, "Filehandle denied for \"%s:%s\"",
fs->fs_host, path);
} else {
errno = error; /* XXX */
plog(XLOG_INFO, "Filehandle error for \"%s:%s\": %m",
fs->fs_host, path);
}
/*
* The error was returned from the remote mount daemon.
* Policy: this error will be cached for now...
*/
return error;
case -1:
/*
* Still thinking about it, but we can re-use.
*/
fp_save = fp;
reuse_id = TRUE;
break;
default:
/*
* Return the error.
* Policy: make sure we recompute if required again
* in case this was caused by a network failure.
* This can thrash mountd's though... If you find
* your mountd going slowly then:
* 1. Add a fork() loop to main.
* 2. Remove the call to innetgr() and don't use
* netgroups, especially if you don't use YP.
*/
error = fp->fh_error;
fp->fh_error = -1;
return error;
}
break;
}
}
/*
* Not in cache
*/
if (fp_save) {
fp = fp_save;
/*
* Re-use existing slot
*/
untimeout(fp->fh_cid);
free_srvr(fp->fh_fs);
free(fp->fh_path);
} else {
fp = ALLOC(fh_cache);
bzero((voidp) fp, sizeof(*fp));
ins_que(&fp->fh_q, &fh_head);
}
if (!reuse_id)
fp->fh_id = FHID_ALLOC();
fp->fh_wchan = wchan;
fp->fh_error = -1;
fp->fh_cid = timeout(FH_TTL, discard_fh, (voidp) fp);
/*
* If the address has changed then don't try to re-use the
* port information
*/
if (fp->fh_sin.sin_addr.s_addr != fs->fs_ip->sin_addr.s_addr) {
fp->fh_sin = *fs->fs_ip;
fp->fh_sin.sin_port = 0;
}
fp->fh_fs = dup_srvr(fs);
fp->fh_path = strdup(path);
error = call_mountd(fp, MOUNTPROC_MNT, got_nfs_fh, wchan);
if (error) {
/*
* Local error - cache for a short period
* just to prevent thrashing.
*/
untimeout(fp->fh_cid);
fp->fh_cid = timeout(error < 0 ? 2 * ALLOWED_MOUNT_TIME : FH_TTL_ERROR,
discard_fh, (voidp) fp);
fp->fh_error = error;
} else {
error = fp->fh_error;
}
return error;
}
static int call_mountd P((fh_cache *fp, u_long proc, fwd_fun f, voidp wchan));
static int call_mountd(fp, proc, f, wchan)
fh_cache *fp;
u_long proc;
fwd_fun f;
voidp wchan;
{
struct rpc_msg mnt_msg;
int len;
char iobuf[8192];
int error;
if (!nfs_auth) {
nfs_auth = authunix_create_default();
if (!nfs_auth)
return ENOBUFS;
}
if (fp->fh_sin.sin_port == 0) {
u_short port;
error = nfs_srvr_port(fp->fh_fs, &port, wchan);
if (error)
return error;
fp->fh_sin.sin_port = port;
}
rpc_msg_init(&mnt_msg, MOUNTPROG, MOUNTVERS, (unsigned long) 0);
len = make_rpc_packet(iobuf, sizeof(iobuf), proc,
&mnt_msg, (voidp) &fp->fh_path, xdr_nfspath, nfs_auth);
if (len > 0) {
error = fwd_packet(MK_RPC_XID(RPC_XID_MOUNTD, fp->fh_id),
(voidp) iobuf, len, &fp->fh_sin, &fp->fh_sin, (voidp) fp->fh_id, f);
} else {
error = -len;
}
return error;
}
/*-------------------------------------------------------------------------*/
/*
* NFS needs the local filesystem, remote filesystem
* remote hostname.
* Local filesystem defaults to remote and vice-versa.
*/
static int nfs_match(fo)
am_opts *fo;
{
if (fo->opt_fs && !fo->opt_rfs)
fo->opt_rfs = fo->opt_fs;
if (!fo->opt_rfs) {
plog(XLOG_USER, "nfs: no remote filesystem specified");
return FALSE;
}
if (!fo->opt_rhost) {
plog(XLOG_USER, "nfs: no remote host specified");
return FALSE;
}
/*
* Determine magic cookie to put in mtab
*/
fo->fs_mtab = (char *) xrealloc(fo->fs_mtab, strlen(fo->opt_rhost) +
strlen(fo->opt_rfs) + 2);
sprintf(fo->fs_mtab, "%s:%s", fo->opt_rhost, fo->opt_rfs);
#ifdef DEBUG
dlog("NFS: mounting remote server \"%s\", remote fs \"%s\" on \"%s\"",
fo->opt_rhost, fo->opt_rfs, fo->opt_fs);
#endif /* DEBUG */
return TRUE;
}
/*
* Initialise am structure for nfs
*/
static int nfs_init(mf)
mntfs *mf;
{
int error;
char *colon = strchr(mf->mf_info, ':');
if (colon == 0)
return ENOENT;
error = prime_nfs_fhandle_cache(colon+1, mf->mf_server, (struct fhstatus *) 0, (voidp) mf);
return error;
}
mount_nfs_fh(fhp, dir, fs_name, opts, mf)
struct fhstatus *fhp;
char *dir;
char *fs_name;
char *opts;
mntfs *mf;
{
struct nfs_args nfs_args;
struct mntent mnt;
int retry;
char *colon;
char *path;
char host[MAXHOSTNAMELEN + MAXPATHLEN + 2];
fserver *fs = mf->mf_server;
int flags;
#ifdef notdef
unsigned short port;
#endif /* notdef */
MTYPE_TYPE type = MOUNT_TYPE_NFS;
bzero((voidp) &nfs_args, sizeof(nfs_args)); /* Paranoid */
/*
* Extract host name to give to kernel
*/
if (!(colon = strchr(fs_name, ':')))
return ENOENT;
#ifndef NFS_ARGS_NEEDS_PATH
*colon = '\0';
#endif
strncpy(host, fs_name, sizeof(host));
#ifndef NFS_ARGS_NEEDS_PATH
*colon = ':';
#endif /* NFS_ARGS_NEEDS_PATH */
path = colon + 1;
bzero((voidp) &nfs_args, sizeof(nfs_args));
mnt.mnt_dir = dir;
mnt.mnt_fsname = fs_name;
mnt.mnt_type = MTAB_TYPE_NFS;
mnt.mnt_opts = opts;
mnt.mnt_freq = 0;
mnt.mnt_passno = 0;
retry = hasmntval(&mnt, "retry");
if (retry <= 0)
retry = 1; /* XXX */
/*again:*/
/*
* set mount args
*/
NFS_FH_DREF(nfs_args.fh, (NFS_FH_TYPE) fhp->fhstatus_u.fhs_fhandle);
#ifdef ULTRIX_HACK
nfs_args.optstr = mnt.mnt_opts;
#endif /* ULTRIX_HACK */
nfs_args.hostname = host;
nfs_args.flags |= NFSMNT_HOSTNAME;
#ifdef HOSTNAMESZ
/*
* Most kernels have a name length restriction.
*/
if (strlen(host) >= HOSTNAMESZ)
strcpy(host + HOSTNAMESZ - 3, "..");
#endif /* HOSTNAMESZ */
if (nfs_args.rsize = hasmntval(&mnt, "rsize"))
nfs_args.flags |= NFSMNT_RSIZE;
if (nfs_args.wsize = hasmntval(&mnt, "wsize"))
nfs_args.flags |= NFSMNT_WSIZE;
if (nfs_args.timeo = hasmntval(&mnt, "timeo"))
nfs_args.flags |= NFSMNT_TIMEO;
if (nfs_args.retrans = hasmntval(&mnt, "retrans"))
nfs_args.flags |= NFSMNT_RETRANS;
#ifdef NFSMNT_BIODS
if (nfs_args.biods = hasmntval(&mnt, "biods"))
nfs_args.flags |= NFSMNT_BIODS;
#endif /* NFSMNT_BIODS */
#ifdef notdef
/*
* This isn't supported by the ping algorithm yet.
* In any case, it is all done in nfs_init().
*/
if (port = hasmntval(&mnt, "port"))
sin.sin_port = htons(port);
else
sin.sin_port = htons(NFS_PORT); /* XXX should use portmapper */
#endif /* notdef */
if (hasmntopt(&mnt, MNTOPT_SOFT) != NULL)
nfs_args.flags |= NFSMNT_SOFT;
#ifdef MNTOPT_INTR
if (hasmntopt(&mnt, MNTOPT_INTR) != NULL)
nfs_args.flags |= NFSMNT_INT;
#endif /* MNTOPT_INTR */
#ifdef MNTOPT_NODEVS
if (hasmntopt(&mnt, MNTOPT_NODEVS) != NULL)
nfs_args.flags |= NFSMNT_NODEVS;
#endif /* MNTOPT_NODEVS */
#ifdef NFSMNT_PGTHRESH
if (nfs_args.pg_thresh = hasmntval(&mnt, "pgthresh"))
nfs_args.flags |= NFSMNT_PGTHRESH;
#endif /* NFSMNT_PGTHRESH */
NFS_SA_DREF(nfs_args, fs->fs_ip);
flags = compute_mount_flags(&mnt);
#ifdef HAS_TCP_NFS
if (hasmntopt(&mnt, "tcp") != NULL)
nfs_args.sotype = SOCK_STREAM;
#endif /* HAS_TCP_NFS */
#ifdef ULTRIX_HACK
/*
* Ultrix passes the flags argument as part of the
* mount data structure, rather than using the
* flags argument to the system call. This is
* confusing...
*/
if (!(nfs_args.flags & NFSMNT_PGTHRESH)) {
nfs_args.pg_thresh = 64; /* 64k - XXX */
nfs_args.flags |= NFSMNT_PGTHRESH;
}
nfs_args.gfs_flags = flags;
flags &= M_RDONLY;
if (flags & M_RDONLY)
nfs_args.flags |= NFSMNT_RONLY;
#endif /* ULTRIX_HACK */
return mount_fs(&mnt, flags, (caddr_t) &nfs_args, retry, type);
}
static mount_nfs(dir, fs_name, opts, mf)
char *dir;
char *fs_name;
char *opts;
mntfs *mf;
{
int error;
struct fhstatus fhs;
char *colon;
if (!(colon = strchr(fs_name, ':')))
return ENOENT;
#ifdef DEBUG
dlog("locating fhandle for %s", fs_name);
#endif /* DEBUG */
error = prime_nfs_fhandle_cache(colon+1, mf->mf_server, &fhs, (voidp) 0);
if (error)
return error;
return mount_nfs_fh(&fhs, dir, fs_name, opts, mf);
}
static int nfs_mount(mp)
am_node *mp;
{
mntfs *mf = mp->am_mnt;
int error = mount_nfs(mf->mf_mount, mf->mf_info,
mf->mf_fo->opt_opts, mf);
#ifdef DEBUG
if (error) {
errno = error;
dlog("mount_nfs: %m");
}
#endif /* DEBUG */
return error;
}
static int nfs_umount(mp)
am_node *mp;
{
mntfs *mf = mp->am_mnt;
int error = UMOUNT_FS(mf->mf_mount);
if (error)
return error;
return 0;
}
static void nfs_umounted(mp)
am_node *mp;
{
#ifdef INFORM_MOUNTD
/*
* Don't bother to inform remote mountd
* that we are finished. Until a full
* track of filehandles is maintained
* the mountd unmount callback cannot
* be done correctly anyway...
*/
mntfs *mf = mp->am_mnt;
fserver *fs;
char *colon, *path;
if (mf->mf_error || mf->mf_refc > 1)
return;
fs = mf->mf_server;
/*
* Call the mount daemon on the server to
* announce that we are not using the fs any more.
*
* This is *wrong*. The mountd should be called
* when the fhandle is flushed from the cache, and
* a reference held to the cached entry while the
* fs is mounted...
*/
colon = path = strchr(mf->mf_info, ':');
if (fs && colon) {
fh_cache f;
#ifdef DEBUG
dlog("calling mountd for %s", mf->mf_info);
#endif /* DEBUG */
*path++ = '\0';
f.fh_path = path;
f.fh_sin = *fs->fs_ip;
f.fh_sin.sin_port = (u_short) 0;
f.fh_fs = fs;
f.fh_id = 0;
f.fh_error = 0;
(void) prime_nfs_fhandle_cache(colon+1, mf->mf_server, (struct fhstatus *) 0, (voidp) mf);
(void) call_mountd(&f, MOUNTPROC_UMNT, (fwd_fun) 0, (voidp) 0);
*colon = ':';
}
#endif /* INFORM_MOUNTD */
}
/*
* Network file system
*/
am_ops nfs_ops = {
"nfs",
nfs_match,
nfs_init,
nfs_mount,
nfs_umount,
efs_lookuppn,
efs_readdir,
0, /* nfs_readlink */
0, /* nfs_mounted */
nfs_umounted,
find_nfs_srvr,
FS_MKMNT|FS_BACKGROUND|FS_AMQINFO
};
#endif /* HAS_NFS */
Continuous source code history from original PDP-7 UNIX to FreeBSD 2, the first fully unencumbered FreeBSD release.