OpenCloudOS-Kernel/fs/nfs/super.c

3021 lines
78 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/fs/nfs/super.c
*
* Copyright (C) 1992 Rick Sladkey
*
* nfs superblock handling functions
*
* Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
* experimental NFS changes. Modularisation taken straight from SYS5 fs.
*
* Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
* J.S.Peatfield@damtp.cam.ac.uk
*
* Split from inode.c by David Howells <dhowells@redhat.com>
*
* - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
* particular server are held in the same superblock
* - NFS superblocks can have several effective roots to the dentry tree
* - directory type roots are spliced into the tree when a path from one root reaches the root
* of another (see nfs_lookup())
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/time.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/stat.h>
#include <linux/errno.h>
#include <linux/unistd.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/addr.h>
#include <linux/sunrpc/stats.h>
#include <linux/sunrpc/metrics.h>
#include <linux/sunrpc/xprtsock.h>
#include <linux/sunrpc/xprtrdma.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_mount.h>
#include <linux/nfs4_mount.h>
#include <linux/lockd/bind.h>
#include <linux/seq_file.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/vfs.h>
#include <linux/inet.h>
#include <linux/in6.h>
#include <linux/slab.h>
#include <net/ipv6.h>
#include <linux/netdevice.h>
#include <linux/nfs_xdr.h>
#include <linux/magic.h>
#include <linux/parser.h>
#include <linux/nsproxy.h>
#include <linux/rcupdate.h>
#include <linux/uaccess.h>
#include "nfs4_fs.h"
#include "callback.h"
#include "delegation.h"
#include "iostat.h"
#include "internal.h"
#include "fscache.h"
#include "nfs4session.h"
#include "pnfs.h"
#include "nfs.h"
#define NFSDBG_FACILITY NFSDBG_VFS
#define NFS_TEXT_DATA 1
#if IS_ENABLED(CONFIG_NFS_V3)
#define NFS_DEFAULT_VERSION 3
#else
#define NFS_DEFAULT_VERSION 2
#endif
#define NFS_MAX_CONNECTIONS 16
enum {
/* Mount options that take no arguments */
Opt_soft, Opt_softerr, Opt_hard,
Opt_posix, Opt_noposix,
Opt_cto, Opt_nocto,
Opt_ac, Opt_noac,
Opt_lock, Opt_nolock,
Opt_udp, Opt_tcp, Opt_rdma,
Opt_acl, Opt_noacl,
Opt_rdirplus, Opt_nordirplus,
Opt_sharecache, Opt_nosharecache,
Opt_resvport, Opt_noresvport,
Opt_fscache, Opt_nofscache,
Opt_migration, Opt_nomigration,
/* Mount options that take integer arguments */
Opt_port,
Opt_rsize, Opt_wsize, Opt_bsize,
Opt_timeo, Opt_retrans,
Opt_acregmin, Opt_acregmax,
Opt_acdirmin, Opt_acdirmax,
Opt_actimeo,
Opt_namelen,
Opt_mountport,
Opt_mountvers,
Opt_minorversion,
/* Mount options that take string arguments */
Opt_nfsvers,
Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
Opt_addr, Opt_mountaddr, Opt_clientaddr,
Opt_nconnect,
Opt_lookupcache,
Opt_fscache_uniq,
Opt_local_lock,
/* Special mount options */
Opt_userspace, Opt_deprecated, Opt_sloppy,
Opt_err
};
static const match_table_t nfs_mount_option_tokens = {
{ Opt_userspace, "bg" },
{ Opt_userspace, "fg" },
{ Opt_userspace, "retry=%s" },
{ Opt_sloppy, "sloppy" },
{ Opt_soft, "soft" },
{ Opt_softerr, "softerr" },
{ Opt_hard, "hard" },
{ Opt_deprecated, "intr" },
{ Opt_deprecated, "nointr" },
{ Opt_posix, "posix" },
{ Opt_noposix, "noposix" },
{ Opt_cto, "cto" },
{ Opt_nocto, "nocto" },
{ Opt_ac, "ac" },
{ Opt_noac, "noac" },
{ Opt_lock, "lock" },
{ Opt_nolock, "nolock" },
{ Opt_udp, "udp" },
{ Opt_tcp, "tcp" },
{ Opt_rdma, "rdma" },
{ Opt_acl, "acl" },
{ Opt_noacl, "noacl" },
{ Opt_rdirplus, "rdirplus" },
{ Opt_nordirplus, "nordirplus" },
{ Opt_sharecache, "sharecache" },
{ Opt_nosharecache, "nosharecache" },
{ Opt_resvport, "resvport" },
{ Opt_noresvport, "noresvport" },
{ Opt_fscache, "fsc" },
{ Opt_nofscache, "nofsc" },
{ Opt_migration, "migration" },
{ Opt_nomigration, "nomigration" },
{ Opt_port, "port=%s" },
{ Opt_rsize, "rsize=%s" },
{ Opt_wsize, "wsize=%s" },
{ Opt_bsize, "bsize=%s" },
{ Opt_timeo, "timeo=%s" },
{ Opt_retrans, "retrans=%s" },
{ Opt_acregmin, "acregmin=%s" },
{ Opt_acregmax, "acregmax=%s" },
{ Opt_acdirmin, "acdirmin=%s" },
{ Opt_acdirmax, "acdirmax=%s" },
{ Opt_actimeo, "actimeo=%s" },
{ Opt_namelen, "namlen=%s" },
{ Opt_mountport, "mountport=%s" },
{ Opt_mountvers, "mountvers=%s" },
{ Opt_minorversion, "minorversion=%s" },
{ Opt_nfsvers, "nfsvers=%s" },
{ Opt_nfsvers, "vers=%s" },
{ Opt_sec, "sec=%s" },
{ Opt_proto, "proto=%s" },
{ Opt_mountproto, "mountproto=%s" },
{ Opt_addr, "addr=%s" },
{ Opt_clientaddr, "clientaddr=%s" },
{ Opt_mounthost, "mounthost=%s" },
{ Opt_mountaddr, "mountaddr=%s" },
{ Opt_nconnect, "nconnect=%s" },
{ Opt_lookupcache, "lookupcache=%s" },
{ Opt_fscache_uniq, "fsc=%s" },
{ Opt_local_lock, "local_lock=%s" },
/* The following needs to be listed after all other options */
{ Opt_nfsvers, "v%s" },
{ Opt_err, NULL }
};
enum {
Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
Opt_xprt_rdma6,
Opt_xprt_err
};
static const match_table_t nfs_xprt_protocol_tokens = {
{ Opt_xprt_udp, "udp" },
{ Opt_xprt_udp6, "udp6" },
{ Opt_xprt_tcp, "tcp" },
{ Opt_xprt_tcp6, "tcp6" },
{ Opt_xprt_rdma, "rdma" },
{ Opt_xprt_rdma6, "rdma6" },
{ Opt_xprt_err, NULL }
};
enum {
Opt_sec_none, Opt_sec_sys,
Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
Opt_sec_err
};
static const match_table_t nfs_secflavor_tokens = {
{ Opt_sec_none, "none" },
{ Opt_sec_none, "null" },
{ Opt_sec_sys, "sys" },
{ Opt_sec_krb5, "krb5" },
{ Opt_sec_krb5i, "krb5i" },
{ Opt_sec_krb5p, "krb5p" },
{ Opt_sec_lkey, "lkey" },
{ Opt_sec_lkeyi, "lkeyi" },
{ Opt_sec_lkeyp, "lkeyp" },
{ Opt_sec_spkm, "spkm3" },
{ Opt_sec_spkmi, "spkm3i" },
{ Opt_sec_spkmp, "spkm3p" },
{ Opt_sec_err, NULL }
};
enum {
Opt_lookupcache_all, Opt_lookupcache_positive,
Opt_lookupcache_none,
Opt_lookupcache_err
};
static match_table_t nfs_lookupcache_tokens = {
{ Opt_lookupcache_all, "all" },
{ Opt_lookupcache_positive, "pos" },
{ Opt_lookupcache_positive, "positive" },
{ Opt_lookupcache_none, "none" },
{ Opt_lookupcache_err, NULL }
};
enum {
Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
Opt_local_lock_none,
Opt_local_lock_err
};
static match_table_t nfs_local_lock_tokens = {
{ Opt_local_lock_all, "all" },
{ Opt_local_lock_flock, "flock" },
{ Opt_local_lock_posix, "posix" },
{ Opt_local_lock_none, "none" },
{ Opt_local_lock_err, NULL }
};
enum {
Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
Opt_vers_4_1, Opt_vers_4_2,
Opt_vers_err
};
static match_table_t nfs_vers_tokens = {
{ Opt_vers_2, "2" },
{ Opt_vers_3, "3" },
{ Opt_vers_4, "4" },
{ Opt_vers_4_0, "4.0" },
{ Opt_vers_4_1, "4.1" },
{ Opt_vers_4_2, "4.2" },
{ Opt_vers_err, NULL }
};
static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *raw_data);
struct file_system_type nfs_fs_type = {
.owner = THIS_MODULE,
.name = "nfs",
.mount = nfs_fs_mount,
.kill_sb = nfs_kill_super,
.fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
};
MODULE_ALIAS_FS("nfs");
EXPORT_SYMBOL_GPL(nfs_fs_type);
struct file_system_type nfs_xdev_fs_type = {
.owner = THIS_MODULE,
.name = "nfs",
.mount = nfs_xdev_mount,
.kill_sb = nfs_kill_super,
.fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
};
const struct super_operations nfs_sops = {
.alloc_inode = nfs_alloc_inode,
.free_inode = nfs_free_inode,
.write_inode = nfs_write_inode,
.drop_inode = nfs_drop_inode,
.statfs = nfs_statfs,
.evict_inode = nfs_evict_inode,
.umount_begin = nfs_umount_begin,
.show_options = nfs_show_options,
.show_devname = nfs_show_devname,
.show_path = nfs_show_path,
.show_stats = nfs_show_stats,
.remount_fs = nfs_remount,
};
EXPORT_SYMBOL_GPL(nfs_sops);
#if IS_ENABLED(CONFIG_NFS_V4)
static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
static int nfs4_validate_mount_data(void *options,
struct nfs_parsed_mount_data *args, const char *dev_name);
struct file_system_type nfs4_fs_type = {
.owner = THIS_MODULE,
.name = "nfs4",
.mount = nfs_fs_mount,
.kill_sb = nfs_kill_super,
.fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
};
MODULE_ALIAS_FS("nfs4");
MODULE_ALIAS("nfs4");
EXPORT_SYMBOL_GPL(nfs4_fs_type);
static int __init register_nfs4_fs(void)
{
return register_filesystem(&nfs4_fs_type);
}
static void unregister_nfs4_fs(void)
{
unregister_filesystem(&nfs4_fs_type);
}
#else
static int __init register_nfs4_fs(void)
{
return 0;
}
static void unregister_nfs4_fs(void)
{
}
#endif
static struct shrinker acl_shrinker = {
.count_objects = nfs_access_cache_count,
.scan_objects = nfs_access_cache_scan,
.seeks = DEFAULT_SEEKS,
};
/*
* Register the NFS filesystems
*/
int __init register_nfs_fs(void)
{
int ret;
ret = register_filesystem(&nfs_fs_type);
if (ret < 0)
goto error_0;
ret = register_nfs4_fs();
if (ret < 0)
goto error_1;
ret = nfs_register_sysctl();
if (ret < 0)
goto error_2;
ret = register_shrinker(&acl_shrinker);
if (ret < 0)
goto error_3;
return 0;
error_3:
nfs_unregister_sysctl();
error_2:
unregister_nfs4_fs();
error_1:
unregister_filesystem(&nfs_fs_type);
error_0:
return ret;
}
/*
* Unregister the NFS filesystems
*/
void __exit unregister_nfs_fs(void)
{
unregister_shrinker(&acl_shrinker);
nfs_unregister_sysctl();
unregister_nfs4_fs();
unregister_filesystem(&nfs_fs_type);
}
bool nfs_sb_active(struct super_block *sb)
{
struct nfs_server *server = NFS_SB(sb);
if (!atomic_inc_not_zero(&sb->s_active))
return false;
if (atomic_inc_return(&server->active) != 1)
atomic_dec(&sb->s_active);
return true;
}
EXPORT_SYMBOL_GPL(nfs_sb_active);
void nfs_sb_deactive(struct super_block *sb)
{
struct nfs_server *server = NFS_SB(sb);
if (atomic_dec_and_test(&server->active))
deactivate_super(sb);
}
EXPORT_SYMBOL_GPL(nfs_sb_deactive);
/*
* Deliver file system statistics to userspace
*/
int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct nfs_server *server = NFS_SB(dentry->d_sb);
unsigned char blockbits;
unsigned long blockres;
struct nfs_fh *fh = NFS_FH(d_inode(dentry));
struct nfs_fsstat res;
int error = -ENOMEM;
res.fattr = nfs_alloc_fattr();
if (res.fattr == NULL)
goto out_err;
error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
if (unlikely(error == -ESTALE)) {
struct dentry *pd_dentry;
pd_dentry = dget_parent(dentry);
nfs_zap_caches(d_inode(pd_dentry));
dput(pd_dentry);
}
nfs_free_fattr(res.fattr);
if (error < 0)
goto out_err;
buf->f_type = NFS_SUPER_MAGIC;
/*
* Current versions of glibc do not correctly handle the
* case where f_frsize != f_bsize. Eventually we want to
* report the value of wtmult in this field.
*/
buf->f_frsize = dentry->d_sb->s_blocksize;
/*
* On most *nix systems, f_blocks, f_bfree, and f_bavail
* are reported in units of f_frsize. Linux hasn't had
* an f_frsize field in its statfs struct until recently,
* thus historically Linux's sys_statfs reports these
* fields in units of f_bsize.
*/
buf->f_bsize = dentry->d_sb->s_blocksize;
blockbits = dentry->d_sb->s_blocksize_bits;
blockres = (1 << blockbits) - 1;
buf->f_blocks = (res.tbytes + blockres) >> blockbits;
buf->f_bfree = (res.fbytes + blockres) >> blockbits;
buf->f_bavail = (res.abytes + blockres) >> blockbits;
buf->f_files = res.tfiles;
buf->f_ffree = res.afiles;
buf->f_namelen = server->namelen;
return 0;
out_err:
dprintk("%s: statfs error = %d\n", __func__, -error);
return error;
}
EXPORT_SYMBOL_GPL(nfs_statfs);
/*
* Map the security flavour number to a name
*/
static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
{
static const struct {
rpc_authflavor_t flavour;
const char *str;
} sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
/* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
{ RPC_AUTH_NULL, "null" },
{ RPC_AUTH_UNIX, "sys" },
{ RPC_AUTH_GSS_KRB5, "krb5" },
{ RPC_AUTH_GSS_KRB5I, "krb5i" },
{ RPC_AUTH_GSS_KRB5P, "krb5p" },
{ RPC_AUTH_GSS_LKEY, "lkey" },
{ RPC_AUTH_GSS_LKEYI, "lkeyi" },
{ RPC_AUTH_GSS_LKEYP, "lkeyp" },
{ RPC_AUTH_GSS_SPKM, "spkm" },
{ RPC_AUTH_GSS_SPKMI, "spkmi" },
{ RPC_AUTH_GSS_SPKMP, "spkmp" },
{ UINT_MAX, "unknown" }
};
int i;
for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
if (sec_flavours[i].flavour == flavour)
break;
}
return sec_flavours[i].str;
}
static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
int showdefaults)
{
struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
char *proto = NULL;
switch (sap->sa_family) {
case AF_INET:
switch (nfss->mountd_protocol) {
case IPPROTO_UDP:
proto = RPCBIND_NETID_UDP;
break;
case IPPROTO_TCP:
proto = RPCBIND_NETID_TCP;
break;
}
break;
case AF_INET6:
switch (nfss->mountd_protocol) {
case IPPROTO_UDP:
proto = RPCBIND_NETID_UDP6;
break;
case IPPROTO_TCP:
proto = RPCBIND_NETID_TCP6;
break;
}
break;
}
if (proto || showdefaults)
seq_printf(m, ",mountproto=%s", proto ?: "auto");
}
static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
int showdefaults)
{
struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
return;
switch (sap->sa_family) {
case AF_INET: {
struct sockaddr_in *sin = (struct sockaddr_in *)sap;
seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
break;
}
case AF_INET6: {
struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
break;
}
default:
if (showdefaults)
seq_puts(m, ",mountaddr=unspecified");
}
if (nfss->mountd_version || showdefaults)
seq_printf(m, ",mountvers=%u", nfss->mountd_version);
if ((nfss->mountd_port &&
nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
showdefaults)
seq_printf(m, ",mountport=%u", nfss->mountd_port);
nfs_show_mountd_netid(m, nfss, showdefaults);
}
#if IS_ENABLED(CONFIG_NFS_V4)
static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
int showdefaults)
{
struct nfs_client *clp = nfss->nfs_client;
seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
}
#else
static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
int showdefaults)
{
}
#endif
static void nfs_show_nfs_version(struct seq_file *m,
unsigned int version,
unsigned int minorversion)
{
seq_printf(m, ",vers=%u", version);
if (version == 4)
seq_printf(m, ".%u", minorversion);
}
/*
* Describe the mount options in force on this server representation
*/
static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
int showdefaults)
{
static const struct proc_nfs_info {
int flag;
const char *str;
const char *nostr;
} nfs_info[] = {
{ NFS_MOUNT_SOFT, ",soft", "" },
{ NFS_MOUNT_SOFTERR, ",softerr", "" },
{ NFS_MOUNT_POSIX, ",posix", "" },
{ NFS_MOUNT_NOCTO, ",nocto", "" },
{ NFS_MOUNT_NOAC, ",noac", "" },
{ NFS_MOUNT_NONLM, ",nolock", "" },
{ NFS_MOUNT_NOACL, ",noacl", "" },
{ NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
{ NFS_MOUNT_UNSHARED, ",nosharecache", "" },
{ NFS_MOUNT_NORESVPORT, ",noresvport", "" },
{ 0, NULL, NULL }
};
const struct proc_nfs_info *nfs_infop;
struct nfs_client *clp = nfss->nfs_client;
u32 version = clp->rpc_ops->version;
int local_flock, local_fcntl;
nfs_show_nfs_version(m, version, clp->cl_minorversion);
seq_printf(m, ",rsize=%u", nfss->rsize);
seq_printf(m, ",wsize=%u", nfss->wsize);
if (nfss->bsize != 0)
seq_printf(m, ",bsize=%u", nfss->bsize);
seq_printf(m, ",namlen=%u", nfss->namelen);
if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
if (!(nfss->flags & (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR)))
seq_puts(m, ",hard");
for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
if (nfss->flags & nfs_infop->flag)
seq_puts(m, nfs_infop->str);
else
seq_puts(m, nfs_infop->nostr);
}
rcu_read_lock();
seq_printf(m, ",proto=%s",
rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
rcu_read_unlock();
if (clp->cl_nconnect > 0)
seq_printf(m, ",nconnect=%u", clp->cl_nconnect);
if (version == 4) {
if (nfss->port != NFS_PORT)
seq_printf(m, ",port=%u", nfss->port);
} else
if (nfss->port)
seq_printf(m, ",port=%u", nfss->port);
seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
if (version != 4)
nfs_show_mountd_options(m, nfss, showdefaults);
else
nfs_show_nfsv4_options(m, nfss, showdefaults);
if (nfss->options & NFS_OPTION_FSCACHE)
seq_puts(m, ",fsc");
if (nfss->options & NFS_OPTION_MIGRATION)
seq_puts(m, ",migration");
if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
seq_puts(m, ",lookupcache=none");
else
seq_puts(m, ",lookupcache=pos");
}
local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
if (!local_flock && !local_fcntl)
seq_puts(m, ",local_lock=none");
else if (local_flock && local_fcntl)
seq_puts(m, ",local_lock=all");
else if (local_flock)
seq_puts(m, ",local_lock=flock");
else
seq_puts(m, ",local_lock=posix");
}
/*
* Describe the mount options on this VFS mountpoint
*/
int nfs_show_options(struct seq_file *m, struct dentry *root)
{
struct nfs_server *nfss = NFS_SB(root->d_sb);
nfs_show_mount_options(m, nfss, 0);
rcu_read_lock();
seq_printf(m, ",addr=%s",
rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
RPC_DISPLAY_ADDR));
rcu_read_unlock();
return 0;
}
EXPORT_SYMBOL_GPL(nfs_show_options);
#if IS_ENABLED(CONFIG_NFS_V4)
static void show_lease(struct seq_file *m, struct nfs_server *server)
{
struct nfs_client *clp = server->nfs_client;
unsigned long expire;
seq_printf(m, ",lease_time=%ld", clp->cl_lease_time / HZ);
expire = clp->cl_last_renewal + clp->cl_lease_time;
seq_printf(m, ",lease_expired=%ld",
time_after(expire, jiffies) ? 0 : (jiffies - expire) / HZ);
}
#ifdef CONFIG_NFS_V4_1
static void show_sessions(struct seq_file *m, struct nfs_server *server)
{
if (nfs4_has_session(server->nfs_client))
seq_puts(m, ",sessions");
}
#else
static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
#endif
#endif
#ifdef CONFIG_NFS_V4_1
static void show_pnfs(struct seq_file *m, struct nfs_server *server)
{
seq_printf(m, ",pnfs=");
if (server->pnfs_curr_ld)
seq_printf(m, "%s", server->pnfs_curr_ld->name);
else
seq_printf(m, "not configured");
}
static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
{
if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
"date='%llu,%u'",
impl_id->name, impl_id->domain,
impl_id->date.seconds, impl_id->date.nseconds);
}
}
#else
#if IS_ENABLED(CONFIG_NFS_V4)
static void show_pnfs(struct seq_file *m, struct nfs_server *server)
{
}
#endif
static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
{
}
#endif
int nfs_show_devname(struct seq_file *m, struct dentry *root)
{
char *page = (char *) __get_free_page(GFP_KERNEL);
char *devname, *dummy;
int err = 0;
if (!page)
return -ENOMEM;
devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
if (IS_ERR(devname))
err = PTR_ERR(devname);
else
seq_escape(m, devname, " \t\n\\");
free_page((unsigned long)page);
return err;
}
EXPORT_SYMBOL_GPL(nfs_show_devname);
int nfs_show_path(struct seq_file *m, struct dentry *dentry)
{
seq_puts(m, "/");
return 0;
}
EXPORT_SYMBOL_GPL(nfs_show_path);
/*
* Present statistical information for this VFS mountpoint
*/
int nfs_show_stats(struct seq_file *m, struct dentry *root)
{
int i, cpu;
struct nfs_server *nfss = NFS_SB(root->d_sb);
struct rpc_auth *auth = nfss->client->cl_auth;
struct nfs_iostats totals = { };
seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
/*
* Display all mount option settings
*/
seq_puts(m, "\n\topts:\t");
seq_puts(m, sb_rdonly(root->d_sb) ? "ro" : "rw");
seq_puts(m, root->d_sb->s_flags & SB_SYNCHRONOUS ? ",sync" : "");
seq_puts(m, root->d_sb->s_flags & SB_NOATIME ? ",noatime" : "");
seq_puts(m, root->d_sb->s_flags & SB_NODIRATIME ? ",nodiratime" : "");
nfs_show_mount_options(m, nfss, 1);
seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
show_implementation_id(m, nfss);
seq_puts(m, "\n\tcaps:\t");
seq_printf(m, "caps=0x%x", nfss->caps);
seq_printf(m, ",wtmult=%u", nfss->wtmult);
seq_printf(m, ",dtsize=%u", nfss->dtsize);
seq_printf(m, ",bsize=%u", nfss->bsize);
seq_printf(m, ",namlen=%u", nfss->namelen);
#if IS_ENABLED(CONFIG_NFS_V4)
if (nfss->nfs_client->rpc_ops->version == 4) {
seq_puts(m, "\n\tnfsv4:\t");
seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
show_sessions(m, nfss);
show_pnfs(m, nfss);
show_lease(m, nfss);
}
#endif
/*
* Display security flavor in effect for this mount
*/
seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
if (auth->au_flavor)
seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
/*
* Display superblock I/O counters
*/
for_each_possible_cpu(cpu) {
struct nfs_iostats *stats;
preempt_disable();
stats = per_cpu_ptr(nfss->io_stats, cpu);
for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
totals.events[i] += stats->events[i];
for (i = 0; i < __NFSIOS_BYTESMAX; i++)
totals.bytes[i] += stats->bytes[i];
#ifdef CONFIG_NFS_FSCACHE
for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
totals.fscache[i] += stats->fscache[i];
#endif
preempt_enable();
}
seq_puts(m, "\n\tevents:\t");
for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
seq_printf(m, "%lu ", totals.events[i]);
seq_puts(m, "\n\tbytes:\t");
for (i = 0; i < __NFSIOS_BYTESMAX; i++)
seq_printf(m, "%Lu ", totals.bytes[i]);
#ifdef CONFIG_NFS_FSCACHE
if (nfss->options & NFS_OPTION_FSCACHE) {
seq_puts(m, "\n\tfsc:\t");
for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
seq_printf(m, "%Lu ", totals.fscache[i]);
}
#endif
seq_putc(m, '\n');
rpc_clnt_show_stats(m, nfss->client);
return 0;
}
EXPORT_SYMBOL_GPL(nfs_show_stats);
/*
* Begin unmount by attempting to remove all automounted mountpoints we added
* in response to xdev traversals and referrals
*/
void nfs_umount_begin(struct super_block *sb)
{
struct nfs_server *server;
struct rpc_clnt *rpc;
server = NFS_SB(sb);
/* -EIO all pending I/O */
rpc = server->client_acl;
if (!IS_ERR(rpc))
rpc_killall_tasks(rpc);
rpc = server->client;
if (!IS_ERR(rpc))
rpc_killall_tasks(rpc);
}
EXPORT_SYMBOL_GPL(nfs_umount_begin);
static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
{
struct nfs_parsed_mount_data *data;
data = kzalloc(sizeof(*data), GFP_KERNEL);
if (data) {
data->timeo = NFS_UNSPEC_TIMEO;
data->retrans = NFS_UNSPEC_RETRANS;
data->acregmin = NFS_DEF_ACREGMIN;
data->acregmax = NFS_DEF_ACREGMAX;
data->acdirmin = NFS_DEF_ACDIRMIN;
data->acdirmax = NFS_DEF_ACDIRMAX;
data->mount_server.port = NFS_UNSPEC_PORT;
data->nfs_server.port = NFS_UNSPEC_PORT;
data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
data->selected_flavor = RPC_AUTH_MAXFLAVOR;
data->minorversion = 0;
data->need_mount = true;
data->net = current->nsproxy->net_ns;
data->lsm_opts = NULL;
}
return data;
}
static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
{
if (data) {
kfree(data->client_address);
kfree(data->mount_server.hostname);
kfree(data->nfs_server.export_path);
kfree(data->nfs_server.hostname);
kfree(data->fscache_uniq);
security_free_mnt_opts(&data->lsm_opts);
kfree(data);
}
}
/*
* Sanity-check a server address provided by the mount command.
*
* Address family must be initialized, and address must not be
* the ANY address for that family.
*/
static int nfs_verify_server_address(struct sockaddr *addr)
{
switch (addr->sa_family) {
case AF_INET: {
struct sockaddr_in *sa = (struct sockaddr_in *)addr;
return sa->sin_addr.s_addr != htonl(INADDR_ANY);
}
case AF_INET6: {
struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
return !ipv6_addr_any(sa);
}
}
dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
return 0;
}
/*
* Select between a default port value and a user-specified port value.
* If a zero value is set, then autobind will be used.
*/
static void nfs_set_port(struct sockaddr *sap, int *port,
const unsigned short default_port)
{
if (*port == NFS_UNSPEC_PORT)
*port = default_port;
rpc_set_port(sap, *port);
}
/*
* Sanity check the NFS transport protocol.
*
*/
static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
{
switch (mnt->nfs_server.protocol) {
case XPRT_TRANSPORT_UDP:
case XPRT_TRANSPORT_TCP:
case XPRT_TRANSPORT_RDMA:
break;
default:
mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
}
}
/*
* For text based NFSv2/v3 mounts, the mount protocol transport default
* settings should depend upon the specified NFS transport.
*/
static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
{
nfs_validate_transport_protocol(mnt);
if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
return;
switch (mnt->nfs_server.protocol) {
case XPRT_TRANSPORT_UDP:
mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
break;
case XPRT_TRANSPORT_TCP:
case XPRT_TRANSPORT_RDMA:
mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
}
}
/*
* Add 'flavor' to 'auth_info' if not already present.
* Returns true if 'flavor' ends up in the list, false otherwise
*/
static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
rpc_authflavor_t flavor)
{
unsigned int i;
unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
/* make sure this flavor isn't already in the list */
for (i = 0; i < auth_info->flavor_len; i++) {
if (flavor == auth_info->flavors[i])
return true;
}
if (auth_info->flavor_len + 1 >= max_flavor_len) {
dfprintk(MOUNT, "NFS: too many sec= flavors\n");
return false;
}
auth_info->flavors[auth_info->flavor_len++] = flavor;
return true;
}
/*
* Return true if 'match' is in auth_info or auth_info is empty.
* Return false otherwise.
*/
bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
rpc_authflavor_t match)
{
int i;
if (!auth_info->flavor_len)
return true;
for (i = 0; i < auth_info->flavor_len; i++) {
if (auth_info->flavors[i] == match)
return true;
}
return false;
}
EXPORT_SYMBOL_GPL(nfs_auth_info_match);
/*
* Parse the value of the 'sec=' option.
*/
static int nfs_parse_security_flavors(char *value,
struct nfs_parsed_mount_data *mnt)
{
substring_t args[MAX_OPT_ARGS];
rpc_authflavor_t pseudoflavor;
char *p;
dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
while ((p = strsep(&value, ":")) != NULL) {
switch (match_token(p, nfs_secflavor_tokens, args)) {
case Opt_sec_none:
pseudoflavor = RPC_AUTH_NULL;
break;
case Opt_sec_sys:
pseudoflavor = RPC_AUTH_UNIX;
break;
case Opt_sec_krb5:
pseudoflavor = RPC_AUTH_GSS_KRB5;
break;
case Opt_sec_krb5i:
pseudoflavor = RPC_AUTH_GSS_KRB5I;
break;
case Opt_sec_krb5p:
pseudoflavor = RPC_AUTH_GSS_KRB5P;
break;
case Opt_sec_lkey:
pseudoflavor = RPC_AUTH_GSS_LKEY;
break;
case Opt_sec_lkeyi:
pseudoflavor = RPC_AUTH_GSS_LKEYI;
break;
case Opt_sec_lkeyp:
pseudoflavor = RPC_AUTH_GSS_LKEYP;
break;
case Opt_sec_spkm:
pseudoflavor = RPC_AUTH_GSS_SPKM;
break;
case Opt_sec_spkmi:
pseudoflavor = RPC_AUTH_GSS_SPKMI;
break;
case Opt_sec_spkmp:
pseudoflavor = RPC_AUTH_GSS_SPKMP;
break;
default:
dfprintk(MOUNT,
"NFS: sec= option '%s' not recognized\n", p);
return 0;
}
if (!nfs_auth_info_add(&mnt->auth_info, pseudoflavor))
return 0;
}
return 1;
}
static int nfs_parse_version_string(char *string,
struct nfs_parsed_mount_data *mnt,
substring_t *args)
{
mnt->flags &= ~NFS_MOUNT_VER3;
switch (match_token(string, nfs_vers_tokens, args)) {
case Opt_vers_2:
mnt->version = 2;
break;
case Opt_vers_3:
mnt->flags |= NFS_MOUNT_VER3;
mnt->version = 3;
break;
case Opt_vers_4:
/* Backward compatibility option. In future,
* the mount program should always supply
* a NFSv4 minor version number.
*/
mnt->version = 4;
break;
case Opt_vers_4_0:
mnt->version = 4;
mnt->minorversion = 0;
break;
case Opt_vers_4_1:
mnt->version = 4;
mnt->minorversion = 1;
break;
case Opt_vers_4_2:
mnt->version = 4;
mnt->minorversion = 2;
break;
default:
return 0;
}
return 1;
}
static int nfs_get_option_str(substring_t args[], char **option)
{
kfree(*option);
*option = match_strdup(args);
return !*option;
}
static int nfs_get_option_ul(substring_t args[], unsigned long *option)
{
int rc;
char *string;
string = match_strdup(args);
if (string == NULL)
return -ENOMEM;
rc = kstrtoul(string, 10, option);
kfree(string);
return rc;
}
static int nfs_get_option_ul_bound(substring_t args[], unsigned long *option,
unsigned long l_bound, unsigned long u_bound)
{
int ret;
ret = nfs_get_option_ul(args, option);
if (ret != 0)
return ret;
if (*option < l_bound || *option > u_bound)
return -ERANGE;
return 0;
}
/*
* Error-check and convert a string of mount options from user space into
* a data structure. The whole mount string is processed; bad options are
* skipped as they are encountered. If there were no errors, return 1;
* otherwise return 0 (zero).
*/
static int nfs_parse_mount_options(char *raw,
struct nfs_parsed_mount_data *mnt)
{
char *p, *string;
int rc, sloppy = 0, invalid_option = 0;
unsigned short protofamily = AF_UNSPEC;
unsigned short mountfamily = AF_UNSPEC;
if (!raw) {
dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
return 1;
}
dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
rc = security_sb_eat_lsm_opts(raw, &mnt->lsm_opts);
if (rc)
goto out_security_failure;
while ((p = strsep(&raw, ",")) != NULL) {
substring_t args[MAX_OPT_ARGS];
unsigned long option;
int token;
if (!*p)
continue;
dfprintk(MOUNT, "NFS: parsing nfs mount option '%s'\n", p);
token = match_token(p, nfs_mount_option_tokens, args);
switch (token) {
/*
* boolean options: foo/nofoo
*/
case Opt_soft:
mnt->flags |= NFS_MOUNT_SOFT;
mnt->flags &= ~NFS_MOUNT_SOFTERR;
break;
case Opt_softerr:
mnt->flags |= NFS_MOUNT_SOFTERR;
mnt->flags &= ~NFS_MOUNT_SOFT;
break;
case Opt_hard:
mnt->flags &= ~(NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR);
break;
case Opt_posix:
mnt->flags |= NFS_MOUNT_POSIX;
break;
case Opt_noposix:
mnt->flags &= ~NFS_MOUNT_POSIX;
break;
case Opt_cto:
mnt->flags &= ~NFS_MOUNT_NOCTO;
break;
case Opt_nocto:
mnt->flags |= NFS_MOUNT_NOCTO;
break;
case Opt_ac:
mnt->flags &= ~NFS_MOUNT_NOAC;
break;
case Opt_noac:
mnt->flags |= NFS_MOUNT_NOAC;
break;
case Opt_lock:
mnt->flags &= ~NFS_MOUNT_NONLM;
mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
NFS_MOUNT_LOCAL_FCNTL);
break;
case Opt_nolock:
mnt->flags |= NFS_MOUNT_NONLM;
mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
NFS_MOUNT_LOCAL_FCNTL);
break;
case Opt_udp:
mnt->flags &= ~NFS_MOUNT_TCP;
mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
break;
case Opt_tcp:
mnt->flags |= NFS_MOUNT_TCP;
mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
break;
case Opt_rdma:
mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
xprt_load_transport(p);
break;
case Opt_acl:
mnt->flags &= ~NFS_MOUNT_NOACL;
break;
case Opt_noacl:
mnt->flags |= NFS_MOUNT_NOACL;
break;
case Opt_rdirplus:
mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
break;
case Opt_nordirplus:
mnt->flags |= NFS_MOUNT_NORDIRPLUS;
break;
case Opt_sharecache:
mnt->flags &= ~NFS_MOUNT_UNSHARED;
break;
case Opt_nosharecache:
mnt->flags |= NFS_MOUNT_UNSHARED;
break;
case Opt_resvport:
mnt->flags &= ~NFS_MOUNT_NORESVPORT;
break;
case Opt_noresvport:
mnt->flags |= NFS_MOUNT_NORESVPORT;
break;
case Opt_fscache:
mnt->options |= NFS_OPTION_FSCACHE;
kfree(mnt->fscache_uniq);
mnt->fscache_uniq = NULL;
break;
case Opt_nofscache:
mnt->options &= ~NFS_OPTION_FSCACHE;
kfree(mnt->fscache_uniq);
mnt->fscache_uniq = NULL;
break;
case Opt_migration:
mnt->options |= NFS_OPTION_MIGRATION;
break;
case Opt_nomigration:
mnt->options &= ~NFS_OPTION_MIGRATION;
break;
/*
* options that take numeric values
*/
case Opt_port:
if (nfs_get_option_ul(args, &option) ||
option > USHRT_MAX)
goto out_invalid_value;
mnt->nfs_server.port = option;
break;
case Opt_rsize:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->rsize = option;
break;
case Opt_wsize:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->wsize = option;
break;
case Opt_bsize:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->bsize = option;
break;
case Opt_timeo:
if (nfs_get_option_ul_bound(args, &option, 1, INT_MAX))
goto out_invalid_value;
mnt->timeo = option;
break;
case Opt_retrans:
if (nfs_get_option_ul_bound(args, &option, 0, INT_MAX))
goto out_invalid_value;
mnt->retrans = option;
break;
case Opt_acregmin:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->acregmin = option;
break;
case Opt_acregmax:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->acregmax = option;
break;
case Opt_acdirmin:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->acdirmin = option;
break;
case Opt_acdirmax:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->acdirmax = option;
break;
case Opt_actimeo:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->acregmin = mnt->acregmax =
mnt->acdirmin = mnt->acdirmax = option;
break;
case Opt_namelen:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->namlen = option;
break;
case Opt_mountport:
if (nfs_get_option_ul(args, &option) ||
option > USHRT_MAX)
goto out_invalid_value;
mnt->mount_server.port = option;
break;
case Opt_mountvers:
if (nfs_get_option_ul(args, &option) ||
option < NFS_MNT_VERSION ||
option > NFS_MNT3_VERSION)
goto out_invalid_value;
mnt->mount_server.version = option;
break;
case Opt_minorversion:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
if (option > NFS4_MAX_MINOR_VERSION)
goto out_invalid_value;
mnt->minorversion = option;
break;
/*
* options that take text values
*/
case Opt_nfsvers:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
rc = nfs_parse_version_string(string, mnt, args);
kfree(string);
if (!rc)
goto out_invalid_value;
break;
case Opt_sec:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
rc = nfs_parse_security_flavors(string, mnt);
kfree(string);
if (!rc) {
dfprintk(MOUNT, "NFS: unrecognized "
"security flavor\n");
return 0;
}
break;
case Opt_proto:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
token = match_token(string,
nfs_xprt_protocol_tokens, args);
protofamily = AF_INET;
switch (token) {
case Opt_xprt_udp6:
protofamily = AF_INET6;
/* fall through */
case Opt_xprt_udp:
mnt->flags &= ~NFS_MOUNT_TCP;
mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
break;
case Opt_xprt_tcp6:
protofamily = AF_INET6;
/* fall through */
case Opt_xprt_tcp:
mnt->flags |= NFS_MOUNT_TCP;
mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
break;
case Opt_xprt_rdma6:
protofamily = AF_INET6;
/* fall through */
case Opt_xprt_rdma:
/* vector side protocols to TCP */
mnt->flags |= NFS_MOUNT_TCP;
mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
xprt_load_transport(string);
break;
default:
dfprintk(MOUNT, "NFS: unrecognized "
"transport protocol\n");
kfree(string);
return 0;
}
kfree(string);
break;
case Opt_mountproto:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
token = match_token(string,
nfs_xprt_protocol_tokens, args);
kfree(string);
mountfamily = AF_INET;
switch (token) {
case Opt_xprt_udp6:
mountfamily = AF_INET6;
/* fall through */
case Opt_xprt_udp:
mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
break;
case Opt_xprt_tcp6:
mountfamily = AF_INET6;
/* fall through */
case Opt_xprt_tcp:
mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
break;
case Opt_xprt_rdma: /* not used for side protocols */
default:
dfprintk(MOUNT, "NFS: unrecognized "
"transport protocol\n");
return 0;
}
break;
case Opt_addr:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
mnt->nfs_server.addrlen =
rpc_pton(mnt->net, string, strlen(string),
(struct sockaddr *)
&mnt->nfs_server.address,
sizeof(mnt->nfs_server.address));
kfree(string);
if (mnt->nfs_server.addrlen == 0)
goto out_invalid_address;
break;
case Opt_clientaddr:
if (nfs_get_option_str(args, &mnt->client_address))
goto out_nomem;
break;
case Opt_mounthost:
if (nfs_get_option_str(args,
&mnt->mount_server.hostname))
goto out_nomem;
break;
case Opt_mountaddr:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
mnt->mount_server.addrlen =
rpc_pton(mnt->net, string, strlen(string),
(struct sockaddr *)
&mnt->mount_server.address,
sizeof(mnt->mount_server.address));
kfree(string);
if (mnt->mount_server.addrlen == 0)
goto out_invalid_address;
break;
case Opt_nconnect:
if (nfs_get_option_ul_bound(args, &option, 1, NFS_MAX_CONNECTIONS))
goto out_invalid_value;
mnt->nfs_server.nconnect = option;
break;
case Opt_lookupcache:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
token = match_token(string,
nfs_lookupcache_tokens, args);
kfree(string);
switch (token) {
case Opt_lookupcache_all:
mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
break;
case Opt_lookupcache_positive:
mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
break;
case Opt_lookupcache_none:
mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
break;
default:
dfprintk(MOUNT, "NFS: invalid "
"lookupcache argument\n");
return 0;
};
break;
case Opt_fscache_uniq:
if (nfs_get_option_str(args, &mnt->fscache_uniq))
goto out_nomem;
mnt->options |= NFS_OPTION_FSCACHE;
break;
case Opt_local_lock:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
token = match_token(string, nfs_local_lock_tokens,
args);
kfree(string);
switch (token) {
case Opt_local_lock_all:
mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
NFS_MOUNT_LOCAL_FCNTL);
break;
case Opt_local_lock_flock:
mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
break;
case Opt_local_lock_posix:
mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
break;
case Opt_local_lock_none:
mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
NFS_MOUNT_LOCAL_FCNTL);
break;
default:
dfprintk(MOUNT, "NFS: invalid "
"local_lock argument\n");
return 0;
};
break;
/*
* Special options
*/
case Opt_sloppy:
sloppy = 1;
dfprintk(MOUNT, "NFS: relaxing parsing rules\n");
break;
case Opt_userspace:
case Opt_deprecated:
dfprintk(MOUNT, "NFS: ignoring mount option "
"'%s'\n", p);
break;
default:
invalid_option = 1;
dfprintk(MOUNT, "NFS: unrecognized mount option "
"'%s'\n", p);
}
}
if (!sloppy && invalid_option)
return 0;
if (mnt->minorversion && mnt->version != 4)
goto out_minorversion_mismatch;
if (mnt->options & NFS_OPTION_MIGRATION &&
(mnt->version != 4 || mnt->minorversion != 0))
goto out_migration_misuse;
/*
* verify that any proto=/mountproto= options match the address
* families in the addr=/mountaddr= options.
*/
if (protofamily != AF_UNSPEC &&
protofamily != mnt->nfs_server.address.ss_family)
goto out_proto_mismatch;
if (mountfamily != AF_UNSPEC) {
if (mnt->mount_server.addrlen) {
if (mountfamily != mnt->mount_server.address.ss_family)
goto out_mountproto_mismatch;
} else {
if (mountfamily != mnt->nfs_server.address.ss_family)
goto out_mountproto_mismatch;
}
}
return 1;
out_mountproto_mismatch:
printk(KERN_INFO "NFS: mount server address does not match mountproto= "
"option\n");
return 0;
out_proto_mismatch:
printk(KERN_INFO "NFS: server address does not match proto= option\n");
return 0;
out_invalid_address:
printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
return 0;
out_invalid_value:
printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
return 0;
out_minorversion_mismatch:
printk(KERN_INFO "NFS: mount option vers=%u does not support "
"minorversion=%u\n", mnt->version, mnt->minorversion);
return 0;
out_migration_misuse:
printk(KERN_INFO
"NFS: 'migration' not supported for this NFS version\n");
return 0;
out_nomem:
printk(KERN_INFO "NFS: not enough memory to parse option\n");
return 0;
out_security_failure:
printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
return 0;
}
/*
* Ensure that a specified authtype in args->auth_info is supported by
* the server. Returns 0 and sets args->selected_flavor if it's ok, and
* -EACCES if not.
*/
static int nfs_verify_authflavors(struct nfs_parsed_mount_data *args,
rpc_authflavor_t *server_authlist, unsigned int count)
{
rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
bool found_auth_null = false;
unsigned int i;
/*
* If the sec= mount option is used, the specified flavor or AUTH_NULL
* must be in the list returned by the server.
*
* AUTH_NULL has a special meaning when it's in the server list - it
* means that the server will ignore the rpc creds, so any flavor
* can be used but still use the sec= that was specified.
*
* Note also that the MNT procedure in MNTv1 does not return a list
* of supported security flavors. In this case, nfs_mount() fabricates
* a security flavor list containing just AUTH_NULL.
*/
for (i = 0; i < count; i++) {
flavor = server_authlist[i];
if (nfs_auth_info_match(&args->auth_info, flavor))
goto out;
if (flavor == RPC_AUTH_NULL)
found_auth_null = true;
}
if (found_auth_null) {
flavor = args->auth_info.flavors[0];
goto out;
}
dfprintk(MOUNT,
"NFS: specified auth flavors not supported by server\n");
return -EACCES;
out:
args->selected_flavor = flavor;
dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->selected_flavor);
return 0;
}
/*
* Use the remote server's MOUNT service to request the NFS file handle
* corresponding to the provided path.
*/
static int nfs_request_mount(struct nfs_parsed_mount_data *args,
struct nfs_fh *root_fh,
rpc_authflavor_t *server_authlist,
unsigned int *server_authlist_len)
{
struct nfs_mount_request request = {
.sap = (struct sockaddr *)
&args->mount_server.address,
.dirpath = args->nfs_server.export_path,
.protocol = args->mount_server.protocol,
.fh = root_fh,
.noresvport = args->flags & NFS_MOUNT_NORESVPORT,
.auth_flav_len = server_authlist_len,
.auth_flavs = server_authlist,
.net = args->net,
};
int status;
if (args->mount_server.version == 0) {
switch (args->version) {
default:
args->mount_server.version = NFS_MNT3_VERSION;
break;
case 2:
args->mount_server.version = NFS_MNT_VERSION;
}
}
request.version = args->mount_server.version;
if (args->mount_server.hostname)
request.hostname = args->mount_server.hostname;
else
request.hostname = args->nfs_server.hostname;
/*
* Construct the mount server's address.
*/
if (args->mount_server.address.ss_family == AF_UNSPEC) {
memcpy(request.sap, &args->nfs_server.address,
args->nfs_server.addrlen);
args->mount_server.addrlen = args->nfs_server.addrlen;
}
request.salen = args->mount_server.addrlen;
nfs_set_port(request.sap, &args->mount_server.port, 0);
/*
* Now ask the mount server to map our export path
* to a file handle.
*/
status = nfs_mount(&request);
if (status != 0) {
dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
request.hostname, status);
return status;
}
return 0;
}
static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
struct nfs_subversion *nfs_mod)
{
int status;
unsigned int i;
bool tried_auth_unix = false;
bool auth_null_in_list = false;
struct nfs_server *server = ERR_PTR(-EACCES);
struct nfs_parsed_mount_data *args = mount_info->parsed;
rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
unsigned int authlist_len = ARRAY_SIZE(authlist);
status = nfs_request_mount(args, mount_info->mntfh, authlist,
&authlist_len);
if (status)
return ERR_PTR(status);
/*
* Was a sec= authflavor specified in the options? First, verify
* whether the server supports it, and then just try to use it if so.
*/
if (args->auth_info.flavor_len > 0) {
status = nfs_verify_authflavors(args, authlist, authlist_len);
dfprintk(MOUNT, "NFS: using auth flavor %u\n",
args->selected_flavor);
if (status)
return ERR_PTR(status);
return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
}
/*
* No sec= option was provided. RFC 2623, section 2.7 suggests we
* SHOULD prefer the flavor listed first. However, some servers list
* AUTH_NULL first. Avoid ever choosing AUTH_NULL.
*/
for (i = 0; i < authlist_len; ++i) {
rpc_authflavor_t flavor;
struct rpcsec_gss_info info;
flavor = authlist[i];
switch (flavor) {
case RPC_AUTH_UNIX:
tried_auth_unix = true;
break;
case RPC_AUTH_NULL:
auth_null_in_list = true;
continue;
default:
if (rpcauth_get_gssinfo(flavor, &info) != 0)
continue;
/* Fallthrough */
}
dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
args->selected_flavor = flavor;
server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
if (!IS_ERR(server))
return server;
}
/*
* Nothing we tried so far worked. At this point, give up if we've
* already tried AUTH_UNIX or if the server's list doesn't contain
* AUTH_NULL
*/
if (tried_auth_unix || !auth_null_in_list)
return server;
/* Last chance! Try AUTH_UNIX */
dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
args->selected_flavor = RPC_AUTH_UNIX;
return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
}
struct dentry *nfs_try_mount(int flags, const char *dev_name,
struct nfs_mount_info *mount_info,
struct nfs_subversion *nfs_mod)
{
struct nfs_server *server;
if (mount_info->parsed->need_mount)
server = nfs_try_mount_request(mount_info, nfs_mod);
else
server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
if (IS_ERR(server))
return ERR_CAST(server);
return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
}
EXPORT_SYMBOL_GPL(nfs_try_mount);
/*
* Split "dev_name" into "hostname:export_path".
*
* The leftmost colon demarks the split between the server's hostname
* and the export path. If the hostname starts with a left square
* bracket, then it may contain colons.
*
* Note: caller frees hostname and export path, even on error.
*/
static int nfs_parse_devname(const char *dev_name,
char **hostname, size_t maxnamlen,
char **export_path, size_t maxpathlen)
{
size_t len;
char *end;
if (unlikely(!dev_name || !*dev_name)) {
dfprintk(MOUNT, "NFS: device name not specified\n");
return -EINVAL;
}
/* Is the host name protected with square brakcets? */
if (*dev_name == '[') {
end = strchr(++dev_name, ']');
if (end == NULL || end[1] != ':')
goto out_bad_devname;
len = end - dev_name;
end++;
} else {
char *comma;
end = strchr(dev_name, ':');
if (end == NULL)
goto out_bad_devname;
len = end - dev_name;
/* kill possible hostname list: not supported */
comma = strchr(dev_name, ',');
if (comma != NULL && comma < end)
len = comma - dev_name;
}
if (len > maxnamlen)
goto out_hostname;
/* N.B. caller will free nfs_server.hostname in all cases */
*hostname = kstrndup(dev_name, len, GFP_KERNEL);
if (*hostname == NULL)
goto out_nomem;
len = strlen(++end);
if (len > maxpathlen)
goto out_path;
*export_path = kstrndup(end, len, GFP_KERNEL);
if (!*export_path)
goto out_nomem;
dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
return 0;
out_bad_devname:
dfprintk(MOUNT, "NFS: device name not in host:path format\n");
return -EINVAL;
out_nomem:
dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
return -ENOMEM;
out_hostname:
dfprintk(MOUNT, "NFS: server hostname too long\n");
return -ENAMETOOLONG;
out_path:
dfprintk(MOUNT, "NFS: export pathname too long\n");
return -ENAMETOOLONG;
}
/*
* Validate the NFS2/NFS3 mount data
* - fills in the mount root filehandle
*
* For option strings, user space handles the following behaviors:
*
* + DNS: mapping server host name to IP address ("addr=" option)
*
* + failure mode: how to behave if a mount request can't be handled
* immediately ("fg/bg" option)
*
* + retry: how often to retry a mount request ("retry=" option)
*
* + breaking back: trying proto=udp after proto=tcp, v2 after v3,
* mountproto=tcp after mountproto=udp, and so on
*/
static int nfs23_validate_mount_data(void *options,
struct nfs_parsed_mount_data *args,
struct nfs_fh *mntfh,
const char *dev_name)
{
struct nfs_mount_data *data = (struct nfs_mount_data *)options;
struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
if (data == NULL)
goto out_no_data;
args->version = NFS_DEFAULT_VERSION;
switch (data->version) {
case 1:
data->namlen = 0; /* fall through */
case 2:
data->bsize = 0; /* fall through */
case 3:
if (data->flags & NFS_MOUNT_VER3)
goto out_no_v3;
data->root.size = NFS2_FHSIZE;
memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
/* Turn off security negotiation */
extra_flags |= NFS_MOUNT_SECFLAVOUR;
/* fall through */
case 4:
if (data->flags & NFS_MOUNT_SECFLAVOUR)
goto out_no_sec;
/* fall through */
case 5:
memset(data->context, 0, sizeof(data->context));
/* fall through */
case 6:
if (data->flags & NFS_MOUNT_VER3) {
if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
goto out_invalid_fh;
mntfh->size = data->root.size;
args->version = 3;
} else {
mntfh->size = NFS2_FHSIZE;
args->version = 2;
}
memcpy(mntfh->data, data->root.data, mntfh->size);
if (mntfh->size < sizeof(mntfh->data))
memset(mntfh->data + mntfh->size, 0,
sizeof(mntfh->data) - mntfh->size);
/*
* Translate to nfs_parsed_mount_data, which nfs_fill_super
* can deal with.
*/
args->flags = data->flags & NFS_MOUNT_FLAGMASK;
args->flags |= extra_flags;
args->rsize = data->rsize;
args->wsize = data->wsize;
args->timeo = data->timeo;
args->retrans = data->retrans;
args->acregmin = data->acregmin;
args->acregmax = data->acregmax;
args->acdirmin = data->acdirmin;
args->acdirmax = data->acdirmax;
args->need_mount = false;
memcpy(sap, &data->addr, sizeof(data->addr));
args->nfs_server.addrlen = sizeof(data->addr);
args->nfs_server.port = ntohs(data->addr.sin_port);
if (sap->sa_family != AF_INET ||
!nfs_verify_server_address(sap))
goto out_no_address;
if (!(data->flags & NFS_MOUNT_TCP))
args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
/* N.B. caller will free nfs_server.hostname in all cases */
args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
args->namlen = data->namlen;
args->bsize = data->bsize;
if (data->flags & NFS_MOUNT_SECFLAVOUR)
args->selected_flavor = data->pseudoflavor;
else
args->selected_flavor = RPC_AUTH_UNIX;
if (!args->nfs_server.hostname)
goto out_nomem;
if (!(data->flags & NFS_MOUNT_NONLM))
args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
NFS_MOUNT_LOCAL_FCNTL);
else
args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
NFS_MOUNT_LOCAL_FCNTL);
/*
* The legacy version 6 binary mount data from userspace has a
* field used only to transport selinux information into the
* the kernel. To continue to support that functionality we
* have a touch of selinux knowledge here in the NFS code. The
* userspace code converted context=blah to just blah so we are
* converting back to the full string selinux understands.
*/
if (data->context[0]){
#ifdef CONFIG_SECURITY_SELINUX
int rc;
data->context[NFS_MAX_CONTEXT_LEN] = '\0';
rc = security_add_mnt_opt("context", data->context,
strlen(data->context), &args->lsm_opts);
if (rc)
return rc;
#else
return -EINVAL;
#endif
}
break;
default:
return NFS_TEXT_DATA;
}
return 0;
out_no_data:
dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
return -EINVAL;
out_no_v3:
dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
data->version);
return -EINVAL;
out_no_sec:
dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
return -EINVAL;
out_nomem:
dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
return -ENOMEM;
out_no_address:
dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
return -EINVAL;
out_invalid_fh:
dfprintk(MOUNT, "NFS: invalid root filehandle\n");
return -EINVAL;
}
#if IS_ENABLED(CONFIG_NFS_V4)
static int nfs_validate_mount_data(struct file_system_type *fs_type,
void *options,
struct nfs_parsed_mount_data *args,
struct nfs_fh *mntfh,
const char *dev_name)
{
if (fs_type == &nfs_fs_type)
return nfs23_validate_mount_data(options, args, mntfh, dev_name);
return nfs4_validate_mount_data(options, args, dev_name);
}
#else
static int nfs_validate_mount_data(struct file_system_type *fs_type,
void *options,
struct nfs_parsed_mount_data *args,
struct nfs_fh *mntfh,
const char *dev_name)
{
return nfs23_validate_mount_data(options, args, mntfh, dev_name);
}
#endif
static int nfs_validate_text_mount_data(void *options,
struct nfs_parsed_mount_data *args,
const char *dev_name)
{
int port = 0;
int max_namelen = PAGE_SIZE;
int max_pathlen = NFS_MAXPATHLEN;
struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
if (nfs_parse_mount_options((char *)options, args) == 0)
return -EINVAL;
if (!nfs_verify_server_address(sap))
goto out_no_address;
if (args->version == 4) {
#if IS_ENABLED(CONFIG_NFS_V4)
if (args->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
port = NFS_RDMA_PORT;
else
port = NFS_PORT;
max_namelen = NFS4_MAXNAMLEN;
max_pathlen = NFS4_MAXPATHLEN;
nfs_validate_transport_protocol(args);
if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
goto out_invalid_transport_udp;
nfs4_validate_mount_flags(args);
#else
goto out_v4_not_compiled;
#endif /* CONFIG_NFS_V4 */
} else {
nfs_set_mount_transport_protocol(args);
if (args->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
port = NFS_RDMA_PORT;
}
nfs_set_port(sap, &args->nfs_server.port, port);
return nfs_parse_devname(dev_name,
&args->nfs_server.hostname,
max_namelen,
&args->nfs_server.export_path,
max_pathlen);
#if !IS_ENABLED(CONFIG_NFS_V4)
out_v4_not_compiled:
dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
return -EPROTONOSUPPORT;
#else
out_invalid_transport_udp:
dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
return -EINVAL;
#endif /* !CONFIG_NFS_V4 */
out_no_address:
dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
return -EINVAL;
}
#define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
| NFS_MOUNT_SECURE \
| NFS_MOUNT_TCP \
| NFS_MOUNT_VER3 \
| NFS_MOUNT_KERBEROS \
| NFS_MOUNT_NONLM \
| NFS_MOUNT_BROKEN_SUID \
| NFS_MOUNT_STRICTLOCK \
| NFS_MOUNT_LEGACY_INTERFACE)
#define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
static int
nfs_compare_remount_data(struct nfs_server *nfss,
struct nfs_parsed_mount_data *data)
{
if ((data->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
data->rsize != nfss->rsize ||
data->wsize != nfss->wsize ||
data->version != nfss->nfs_client->rpc_ops->version ||
data->minorversion != nfss->nfs_client->cl_minorversion ||
data->retrans != nfss->client->cl_timeout->to_retries ||
!nfs_auth_info_match(&data->auth_info, nfss->client->cl_auth->au_flavor) ||
data->acregmin != nfss->acregmin / HZ ||
data->acregmax != nfss->acregmax / HZ ||
data->acdirmin != nfss->acdirmin / HZ ||
data->acdirmax != nfss->acdirmax / HZ ||
data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
(data->options & NFS_OPTION_FSCACHE) != (nfss->options & NFS_OPTION_FSCACHE) ||
data->nfs_server.port != nfss->port ||
data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
!rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
(struct sockaddr *)&nfss->nfs_client->cl_addr))
return -EINVAL;
return 0;
}
int
nfs_remount(struct super_block *sb, int *flags, char *raw_data)
{
int error;
struct nfs_server *nfss = sb->s_fs_info;
struct nfs_parsed_mount_data *data;
struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
u32 nfsvers = nfss->nfs_client->rpc_ops->version;
sync_filesystem(sb);
/*
* Userspace mount programs that send binary options generally send
* them populated with default values. We have no way to know which
* ones were explicitly specified. Fall back to legacy behavior and
* just return success.
*/
if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
(nfsvers <= 3 && (!options || (options->version >= 1 &&
options->version <= 6))))
return 0;
data = nfs_alloc_parsed_mount_data();
if (data == NULL)
return -ENOMEM;
/* fill out struct with values from existing mount */
data->flags = nfss->flags;
data->rsize = nfss->rsize;
data->wsize = nfss->wsize;
data->retrans = nfss->client->cl_timeout->to_retries;
data->selected_flavor = nfss->client->cl_auth->au_flavor;
data->acregmin = nfss->acregmin / HZ;
data->acregmax = nfss->acregmax / HZ;
data->acdirmin = nfss->acdirmin / HZ;
data->acdirmax = nfss->acdirmax / HZ;
data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
data->nfs_server.port = nfss->port;
data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
data->version = nfsvers;
data->minorversion = nfss->nfs_client->cl_minorversion;
data->net = current->nsproxy->net_ns;
memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
data->nfs_server.addrlen);
/* overwrite those values with any that were specified */
error = -EINVAL;
if (!nfs_parse_mount_options((char *)options, data))
goto out;
/*
* noac is a special case. It implies -o sync, but that's not
* necessarily reflected in the mtab options. do_remount_sb
* will clear SB_SYNCHRONOUS if -o sync wasn't specified in the
* remount options, so we have to explicitly reset it.
*/
if (data->flags & NFS_MOUNT_NOAC)
*flags |= SB_SYNCHRONOUS;
/* compare new mount options with old ones */
error = nfs_compare_remount_data(nfss, data);
if (!error)
error = security_sb_remount(sb, data->lsm_opts);
out:
nfs_free_parsed_mount_data(data);
return error;
}
EXPORT_SYMBOL_GPL(nfs_remount);
/*
* Initialise the common bits of the superblock
*/
static void nfs_initialise_sb(struct super_block *sb)
{
struct nfs_server *server = NFS_SB(sb);
sb->s_magic = NFS_SUPER_MAGIC;
/* We probably want something more informative here */
snprintf(sb->s_id, sizeof(sb->s_id),
"%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
if (sb->s_blocksize == 0)
sb->s_blocksize = nfs_block_bits(server->wsize,
&sb->s_blocksize_bits);
nfs_super_set_maxbytes(sb, server->maxfilesize);
}
/*
* Finish setting up an NFS2/3 superblock
*/
void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
{
struct nfs_parsed_mount_data *data = mount_info->parsed;
struct nfs_server *server = NFS_SB(sb);
sb->s_blocksize_bits = 0;
sb->s_blocksize = 0;
sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
sb->s_op = server->nfs_client->cl_nfs_mod->sops;
if (data && data->bsize)
sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
switch (server->nfs_client->rpc_ops->version) {
case 2:
sb->s_time_gran = 1000;
sb->s_time_min = 0;
sb->s_time_max = U32_MAX;
break;
case 3:
/*
* The VFS shouldn't apply the umask to mode bits.
* We will do so ourselves when necessary.
*/
sb->s_flags |= SB_POSIXACL;
sb->s_time_gran = 1;
sb->s_time_min = 0;
sb->s_time_max = U32_MAX;
sb->s_export_op = &nfs_export_ops;
break;
case 4:
sb->s_flags |= SB_POSIXACL;
sb->s_time_gran = 1;
sb->s_time_min = S64_MIN;
sb->s_time_max = S64_MAX;
if (server->caps & NFS_CAP_ATOMIC_OPEN_V1)
sb->s_export_op = &nfs_export_ops;
break;
}
nfs_initialise_sb(sb);
}
EXPORT_SYMBOL_GPL(nfs_fill_super);
/*
* Finish setting up a cloned NFS2/3/4 superblock
*/
static void nfs_clone_super(struct super_block *sb,
struct nfs_mount_info *mount_info)
{
const struct super_block *old_sb = mount_info->cloned->sb;
struct nfs_server *server = NFS_SB(sb);
sb->s_blocksize_bits = old_sb->s_blocksize_bits;
sb->s_blocksize = old_sb->s_blocksize;
sb->s_maxbytes = old_sb->s_maxbytes;
sb->s_xattr = old_sb->s_xattr;
sb->s_op = old_sb->s_op;
sb->s_export_op = old_sb->s_export_op;
if (server->nfs_client->rpc_ops->version != 2) {
/* The VFS shouldn't apply the umask to mode bits. We will do
* so ourselves when necessary.
*/
sb->s_flags |= SB_POSIXACL;
sb->s_time_gran = 1;
} else
sb->s_time_gran = 1000;
if (server->nfs_client->rpc_ops->version != 4) {
sb->s_time_min = 0;
sb->s_time_max = U32_MAX;
} else {
sb->s_time_min = S64_MIN;
sb->s_time_max = S64_MAX;
}
nfs_initialise_sb(sb);
}
static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
{
const struct nfs_server *a = s->s_fs_info;
const struct rpc_clnt *clnt_a = a->client;
const struct rpc_clnt *clnt_b = b->client;
if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
goto Ebusy;
if (a->nfs_client != b->nfs_client)
goto Ebusy;
if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
goto Ebusy;
if (a->wsize != b->wsize)
goto Ebusy;
if (a->rsize != b->rsize)
goto Ebusy;
if (a->acregmin != b->acregmin)
goto Ebusy;
if (a->acregmax != b->acregmax)
goto Ebusy;
if (a->acdirmin != b->acdirmin)
goto Ebusy;
if (a->acdirmax != b->acdirmax)
goto Ebusy;
if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
goto Ebusy;
return 1;
Ebusy:
return 0;
}
struct nfs_sb_mountdata {
struct nfs_server *server;
int mntflags;
};
static int nfs_set_super(struct super_block *s, void *data)
{
struct nfs_sb_mountdata *sb_mntdata = data;
struct nfs_server *server = sb_mntdata->server;
int ret;
s->s_flags = sb_mntdata->mntflags;
s->s_fs_info = server;
s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
ret = set_anon_super(s, server);
if (ret == 0)
server->s_dev = s->s_dev;
return ret;
}
static int nfs_compare_super_address(struct nfs_server *server1,
struct nfs_server *server2)
{
struct sockaddr *sap1, *sap2;
struct rpc_xprt *xprt1 = server1->client->cl_xprt;
struct rpc_xprt *xprt2 = server2->client->cl_xprt;
if (!net_eq(xprt1->xprt_net, xprt2->xprt_net))
return 0;
sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
if (sap1->sa_family != sap2->sa_family)
return 0;
switch (sap1->sa_family) {
case AF_INET: {
struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
return 0;
if (sin1->sin_port != sin2->sin_port)
return 0;
break;
}
case AF_INET6: {
struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
return 0;
if (sin1->sin6_port != sin2->sin6_port)
return 0;
break;
}
default:
return 0;
}
return 1;
}
static int nfs_compare_userns(const struct nfs_server *old,
const struct nfs_server *new)
{
const struct user_namespace *oldns = &init_user_ns;
const struct user_namespace *newns = &init_user_ns;
if (old->client && old->client->cl_cred)
oldns = old->client->cl_cred->user_ns;
if (new->client && new->client->cl_cred)
newns = new->client->cl_cred->user_ns;
if (oldns != newns)
return 0;
return 1;
}
static int nfs_compare_super(struct super_block *sb, void *data)
{
struct nfs_sb_mountdata *sb_mntdata = data;
struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
int mntflags = sb_mntdata->mntflags;
if (!nfs_compare_super_address(old, server))
return 0;
/* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
if (old->flags & NFS_MOUNT_UNSHARED)
return 0;
if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
return 0;
if (!nfs_compare_userns(old, server))
return 0;
return nfs_compare_mount_options(sb, server, mntflags);
}
#ifdef CONFIG_NFS_FSCACHE
static void nfs_get_cache_cookie(struct super_block *sb,
struct nfs_parsed_mount_data *parsed,
struct nfs_clone_mount *cloned)
{
struct nfs_server *nfss = NFS_SB(sb);
char *uniq = NULL;
int ulen = 0;
nfss->fscache_key = NULL;
nfss->fscache = NULL;
if (parsed) {
if (!(parsed->options & NFS_OPTION_FSCACHE))
return;
if (parsed->fscache_uniq) {
uniq = parsed->fscache_uniq;
ulen = strlen(parsed->fscache_uniq);
}
} else if (cloned) {
struct nfs_server *mnt_s = NFS_SB(cloned->sb);
if (!(mnt_s->options & NFS_OPTION_FSCACHE))
return;
if (mnt_s->fscache_key) {
uniq = mnt_s->fscache_key->key.uniquifier;
ulen = mnt_s->fscache_key->key.uniq_len;
};
} else
return;
nfs_fscache_get_super_cookie(sb, uniq, ulen);
}
#else
static void nfs_get_cache_cookie(struct super_block *sb,
struct nfs_parsed_mount_data *parsed,
struct nfs_clone_mount *cloned)
{
}
#endif
int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
struct nfs_mount_info *mount_info)
{
int error;
unsigned long kflags = 0, kflags_out = 0;
if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
kflags |= SECURITY_LSM_NATIVE_LABELS;
error = security_sb_set_mnt_opts(s, mount_info->parsed->lsm_opts,
kflags, &kflags_out);
if (error)
goto err;
if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
!(kflags_out & SECURITY_LSM_NATIVE_LABELS))
NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
err:
return error;
}
EXPORT_SYMBOL_GPL(nfs_set_sb_security);
int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
struct nfs_mount_info *mount_info)
{
int error;
unsigned long kflags = 0, kflags_out = 0;
/* clone any lsm security options from the parent to the new sb */
if (d_inode(mntroot)->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
return -ESTALE;
if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
kflags |= SECURITY_LSM_NATIVE_LABELS;
error = security_sb_clone_mnt_opts(mount_info->cloned->sb, s, kflags,
&kflags_out);
if (error)
return error;
if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
!(kflags_out & SECURITY_LSM_NATIVE_LABELS))
NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
return 0;
}
EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
static void nfs_set_readahead(struct backing_dev_info *bdi,
unsigned long iomax_pages)
{
bdi->ra_pages = VM_READAHEAD_PAGES;
bdi->io_pages = iomax_pages;
}
struct dentry *nfs_fs_mount_common(struct nfs_server *server,
int flags, const char *dev_name,
struct nfs_mount_info *mount_info,
struct nfs_subversion *nfs_mod)
{
struct super_block *s;
struct dentry *mntroot = ERR_PTR(-ENOMEM);
int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
struct nfs_sb_mountdata sb_mntdata = {
.mntflags = flags,
.server = server,
};
int error;
if (server->flags & NFS_MOUNT_UNSHARED)
compare_super = NULL;
/* -o noac implies -o sync */
if (server->flags & NFS_MOUNT_NOAC)
sb_mntdata.mntflags |= SB_SYNCHRONOUS;
if (mount_info->cloned != NULL && mount_info->cloned->sb != NULL)
if (mount_info->cloned->sb->s_flags & SB_SYNCHRONOUS)
sb_mntdata.mntflags |= SB_SYNCHRONOUS;
/* Get a superblock - note that we may end up sharing one that already exists */
s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
if (IS_ERR(s)) {
mntroot = ERR_CAST(s);
goto out_err_nosb;
}
if (s->s_fs_info != server) {
nfs_free_server(server);
server = NULL;
} else {
error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev),
MINOR(server->s_dev));
if (error) {
mntroot = ERR_PTR(error);
goto error_splat_super;
}
nfs_set_readahead(s->s_bdi, server->rpages);
server->super = s;
}
if (!s->s_root) {
/* initial superblock/root creation */
mount_info->fill_super(s, mount_info);
nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
if (!(server->flags & NFS_MOUNT_UNSHARED))
s->s_iflags |= SB_I_MULTIROOT;
}
mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
if (IS_ERR(mntroot))
goto error_splat_super;
error = mount_info->set_security(s, mntroot, mount_info);
if (error)
goto error_splat_root;
s->s_flags |= SB_ACTIVE;
out:
return mntroot;
out_err_nosb:
nfs_free_server(server);
goto out;
error_splat_root:
dput(mntroot);
mntroot = ERR_PTR(error);
error_splat_super:
deactivate_locked_super(s);
goto out;
}
EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *raw_data)
{
struct nfs_mount_info mount_info = {
.fill_super = nfs_fill_super,
.set_security = nfs_set_sb_security,
};
struct dentry *mntroot = ERR_PTR(-ENOMEM);
struct nfs_subversion *nfs_mod;
int error;
mount_info.parsed = nfs_alloc_parsed_mount_data();
mount_info.mntfh = nfs_alloc_fhandle();
if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
goto out;
/* Validate the mount data */
error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
if (error == NFS_TEXT_DATA)
error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
if (error < 0) {
mntroot = ERR_PTR(error);
goto out;
}
nfs_mod = get_nfs_version(mount_info.parsed->version);
if (IS_ERR(nfs_mod)) {
mntroot = ERR_CAST(nfs_mod);
goto out;
}
mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
put_nfs_version(nfs_mod);
out:
nfs_free_parsed_mount_data(mount_info.parsed);
nfs_free_fhandle(mount_info.mntfh);
return mntroot;
}
EXPORT_SYMBOL_GPL(nfs_fs_mount);
/*
* Destroy an NFS2/3 superblock
*/
void nfs_kill_super(struct super_block *s)
{
struct nfs_server *server = NFS_SB(s);
dev_t dev = s->s_dev;
generic_shutdown_super(s);
nfs_fscache_release_super_cookie(s);
nfs_free_server(server);
free_anon_bdev(dev);
}
EXPORT_SYMBOL_GPL(nfs_kill_super);
/*
* Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
*/
static struct dentry *
nfs_xdev_mount(struct file_system_type *fs_type, int flags,
const char *dev_name, void *raw_data)
{
struct nfs_clone_mount *data = raw_data;
struct nfs_mount_info mount_info = {
.fill_super = nfs_clone_super,
.set_security = nfs_clone_sb_security,
.cloned = data,
};
struct nfs_server *server;
struct dentry *mntroot = ERR_PTR(-ENOMEM);
struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
dprintk("--> nfs_xdev_mount()\n");
mount_info.mntfh = mount_info.cloned->fh;
/* create a new volume representation */
server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
if (IS_ERR(server))
mntroot = ERR_CAST(server);
else
mntroot = nfs_fs_mount_common(server, flags,
dev_name, &mount_info, nfs_mod);
dprintk("<-- nfs_xdev_mount() = %ld\n",
IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
return mntroot;
}
#if IS_ENABLED(CONFIG_NFS_V4)
static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
{
args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
}
/*
* Validate NFSv4 mount options
*/
static int nfs4_validate_mount_data(void *options,
struct nfs_parsed_mount_data *args,
const char *dev_name)
{
struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
char *c;
if (data == NULL)
goto out_no_data;
args->version = 4;
switch (data->version) {
case 1:
if (data->host_addrlen > sizeof(args->nfs_server.address))
goto out_no_address;
if (data->host_addrlen == 0)
goto out_no_address;
args->nfs_server.addrlen = data->host_addrlen;
if (copy_from_user(sap, data->host_addr, data->host_addrlen))
return -EFAULT;
if (!nfs_verify_server_address(sap))
goto out_no_address;
args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
if (data->auth_flavourlen) {
rpc_authflavor_t pseudoflavor;
if (data->auth_flavourlen > 1)
goto out_inval_auth;
if (copy_from_user(&pseudoflavor,
data->auth_flavours,
sizeof(pseudoflavor)))
return -EFAULT;
args->selected_flavor = pseudoflavor;
} else
args->selected_flavor = RPC_AUTH_UNIX;
c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
if (IS_ERR(c))
return PTR_ERR(c);
args->nfs_server.hostname = c;
c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
if (IS_ERR(c))
return PTR_ERR(c);
args->nfs_server.export_path = c;
dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
c = strndup_user(data->client_addr.data, 16);
if (IS_ERR(c))
return PTR_ERR(c);
args->client_address = c;
/*
* Translate to nfs_parsed_mount_data, which nfs4_fill_super
* can deal with.
*/
args->flags = data->flags & NFS4_MOUNT_FLAGMASK;
args->rsize = data->rsize;
args->wsize = data->wsize;
args->timeo = data->timeo;
args->retrans = data->retrans;
args->acregmin = data->acregmin;
args->acregmax = data->acregmax;
args->acdirmin = data->acdirmin;
args->acdirmax = data->acdirmax;
args->nfs_server.protocol = data->proto;
nfs_validate_transport_protocol(args);
if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
goto out_invalid_transport_udp;
break;
default:
return NFS_TEXT_DATA;
}
return 0;
out_no_data:
dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
return -EINVAL;
out_inval_auth:
dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
data->auth_flavourlen);
return -EINVAL;
out_no_address:
dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
return -EINVAL;
out_invalid_transport_udp:
dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
return -EINVAL;
}
/*
* NFS v4 module parameters need to stay in the
* NFS client for backwards compatibility
*/
unsigned int nfs_callback_set_tcpport;
unsigned short nfs_callback_nr_threads;
/* Default cache timeout is 10 minutes */
unsigned int nfs_idmap_cache_timeout = 600;
/* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
bool nfs4_disable_idmapping = true;
unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE;
unsigned short send_implementation_id = 1;
char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
bool recover_lost_locks = false;
EXPORT_SYMBOL_GPL(nfs_callback_nr_threads);
EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
EXPORT_SYMBOL_GPL(max_session_slots);
EXPORT_SYMBOL_GPL(max_session_cb_slots);
EXPORT_SYMBOL_GPL(send_implementation_id);
EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
EXPORT_SYMBOL_GPL(recover_lost_locks);
#define NFS_CALLBACK_MAXPORTNR (65535U)
static int param_set_portnr(const char *val, const struct kernel_param *kp)
{
unsigned long num;
int ret;
if (!val)
return -EINVAL;
ret = kstrtoul(val, 0, &num);
if (ret || num > NFS_CALLBACK_MAXPORTNR)
return -EINVAL;
*((unsigned int *)kp->arg) = num;
return 0;
}
static const struct kernel_param_ops param_ops_portnr = {
.set = param_set_portnr,
.get = param_get_uint,
};
#define param_check_portnr(name, p) __param_check(name, p, unsigned int);
module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644);
MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be "
"assigned to the NFSv4 callback channels.");
module_param(nfs_idmap_cache_timeout, int, 0644);
module_param(nfs4_disable_idmapping, bool, 0644);
module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
NFS4_CLIENT_ID_UNIQ_LEN, 0600);
MODULE_PARM_DESC(nfs4_disable_idmapping,
"Turn off NFSv4 idmapping when using 'sec=sys'");
module_param(max_session_slots, ushort, 0644);
MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
"requests the client will negotiate");
module_param(max_session_cb_slots, ushort, 0644);
MODULE_PARM_DESC(max_session_cb_slots, "Maximum number of parallel NFSv4.1 "
"callbacks the client will process for a given server");
module_param(send_implementation_id, ushort, 0644);
MODULE_PARM_DESC(send_implementation_id,
"Send implementation ID with NFSv4.1 exchange_id");
MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
module_param(recover_lost_locks, bool, 0644);
MODULE_PARM_DESC(recover_lost_locks,
"If the server reports that a lock might be lost, "
"try to recover it risking data corruption.");
#endif /* CONFIG_NFS_V4 */