linux/fs/nfs/super.c
Steve Dickson 74dd34e6e8 NFS: Added support to turn off the NFSv3 READDIRPLUS RPC.
READDIRPLUS can be a performance hindrance when the client is working with
large directories. In addition, some servers still have bugs in their
implementations (e.g. Tru64 returns wrong values for the fsid).

Add a mount flag to enable users to turn it off at mount time following the
implementation in Apple's NFS client.

Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-04-30 22:17:16 -07:00

1074 lines
26 KiB
C

/*
* linux/fs/nfs/super.c
*
* Copyright (C) 1992 Rick Sladkey
*
* nfs superblock handling functions
*
* Modularised by Alan Cox <Alan.Cox@linux.org>, 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/stats.h>
#include <linux/sunrpc/metrics.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_mount.h>
#include <linux/nfs4_mount.h>
#include <linux/lockd/bind.h>
#include <linux/smp_lock.h>
#include <linux/seq_file.h>
#include <linux/mount.h>
#include <linux/nfs_idmap.h>
#include <linux/vfs.h>
#include <linux/inet.h>
#include <linux/nfs_xdr.h>
#include <linux/magic.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include "nfs4_fs.h"
#include "callback.h"
#include "delegation.h"
#include "iostat.h"
#include "internal.h"
#define NFSDBG_FACILITY NFSDBG_VFS
static void nfs_umount_begin(struct vfsmount *, int);
static int nfs_statfs(struct dentry *, struct kstatfs *);
static int nfs_show_options(struct seq_file *, struct vfsmount *);
static int nfs_show_stats(struct seq_file *, struct vfsmount *);
static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
static int nfs_xdev_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
static void nfs_kill_super(struct super_block *);
static struct file_system_type nfs_fs_type = {
.owner = THIS_MODULE,
.name = "nfs",
.get_sb = nfs_get_sb,
.kill_sb = nfs_kill_super,
.fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
};
struct file_system_type nfs_xdev_fs_type = {
.owner = THIS_MODULE,
.name = "nfs",
.get_sb = nfs_xdev_get_sb,
.kill_sb = nfs_kill_super,
.fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
};
static const struct super_operations nfs_sops = {
.alloc_inode = nfs_alloc_inode,
.destroy_inode = nfs_destroy_inode,
.write_inode = nfs_write_inode,
.statfs = nfs_statfs,
.clear_inode = nfs_clear_inode,
.umount_begin = nfs_umount_begin,
.show_options = nfs_show_options,
.show_stats = nfs_show_stats,
};
#ifdef CONFIG_NFS_V4
static int nfs4_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
static int nfs4_xdev_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
static int nfs4_referral_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
static void nfs4_kill_super(struct super_block *sb);
static struct file_system_type nfs4_fs_type = {
.owner = THIS_MODULE,
.name = "nfs4",
.get_sb = nfs4_get_sb,
.kill_sb = nfs4_kill_super,
.fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
};
struct file_system_type nfs4_xdev_fs_type = {
.owner = THIS_MODULE,
.name = "nfs4",
.get_sb = nfs4_xdev_get_sb,
.kill_sb = nfs4_kill_super,
.fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
};
struct file_system_type nfs4_referral_fs_type = {
.owner = THIS_MODULE,
.name = "nfs4",
.get_sb = nfs4_referral_get_sb,
.kill_sb = nfs4_kill_super,
.fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
};
static const struct super_operations nfs4_sops = {
.alloc_inode = nfs_alloc_inode,
.destroy_inode = nfs_destroy_inode,
.write_inode = nfs_write_inode,
.statfs = nfs_statfs,
.clear_inode = nfs4_clear_inode,
.umount_begin = nfs_umount_begin,
.show_options = nfs_show_options,
.show_stats = nfs_show_stats,
};
#endif
static struct shrinker *acl_shrinker;
/*
* 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 = nfs_register_sysctl();
if (ret < 0)
goto error_1;
#ifdef CONFIG_NFS_V4
ret = register_filesystem(&nfs4_fs_type);
if (ret < 0)
goto error_2;
#endif
acl_shrinker = set_shrinker(DEFAULT_SEEKS, nfs_access_cache_shrinker);
return 0;
#ifdef CONFIG_NFS_V4
error_2:
nfs_unregister_sysctl();
#endif
error_1:
unregister_filesystem(&nfs_fs_type);
error_0:
return ret;
}
/*
* Unregister the NFS filesystems
*/
void __exit unregister_nfs_fs(void)
{
if (acl_shrinker != NULL)
remove_shrinker(acl_shrinker);
#ifdef CONFIG_NFS_V4
unregister_filesystem(&nfs4_fs_type);
nfs_unregister_sysctl();
#endif
unregister_filesystem(&nfs_fs_type);
}
/*
* Deliver file system statistics to userspace
*/
static 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(dentry->d_inode);
struct nfs_fattr fattr;
struct nfs_fsstat res = {
.fattr = &fattr,
};
int error;
lock_kernel();
error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
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;
unlock_kernel();
return 0;
out_err:
dprintk("%s: statfs error = %d\n", __FUNCTION__, -error);
unlock_kernel();
return error;
}
/*
* 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[] = {
{ 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" },
{ -1, "unknown" }
};
int i;
for (i=0; sec_flavours[i].flavour != -1; i++) {
if (sec_flavours[i].flavour == flavour)
break;
}
return sec_flavours[i].str;
}
/*
* 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", ",hard" },
{ NFS_MOUNT_INTR, ",intr", "" },
{ NFS_MOUNT_NOCTO, ",nocto", "" },
{ NFS_MOUNT_NOAC, ",noac", "" },
{ NFS_MOUNT_NONLM, ",nolock", "" },
{ NFS_MOUNT_NOACL, ",noacl", "" },
{ NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
{ 0, NULL, NULL }
};
const struct proc_nfs_info *nfs_infop;
struct nfs_client *clp = nfss->nfs_client;
char buf[12];
const char *proto;
seq_printf(m, ",vers=%d", clp->rpc_ops->version);
seq_printf(m, ",rsize=%d", nfss->rsize);
seq_printf(m, ",wsize=%d", nfss->wsize);
if (nfss->acregmin != 3*HZ || showdefaults)
seq_printf(m, ",acregmin=%d", nfss->acregmin/HZ);
if (nfss->acregmax != 60*HZ || showdefaults)
seq_printf(m, ",acregmax=%d", nfss->acregmax/HZ);
if (nfss->acdirmin != 30*HZ || showdefaults)
seq_printf(m, ",acdirmin=%d", nfss->acdirmin/HZ);
if (nfss->acdirmax != 60*HZ || showdefaults)
seq_printf(m, ",acdirmax=%d", nfss->acdirmax/HZ);
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);
}
switch (nfss->client->cl_xprt->prot) {
case IPPROTO_TCP:
proto = "tcp";
break;
case IPPROTO_UDP:
proto = "udp";
break;
default:
snprintf(buf, sizeof(buf), "%u", nfss->client->cl_xprt->prot);
proto = buf;
}
seq_printf(m, ",proto=%s", proto);
seq_printf(m, ",timeo=%lu", 10U * clp->retrans_timeo / HZ);
seq_printf(m, ",retrans=%u", clp->retrans_count);
seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
}
/*
* Describe the mount options on this VFS mountpoint
*/
static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
{
struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
nfs_show_mount_options(m, nfss, 0);
seq_puts(m, ",addr=");
seq_escape(m, nfss->nfs_client->cl_hostname, " \t\n\\");
return 0;
}
/*
* Present statistical information for this VFS mountpoint
*/
static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
{
int i, cpu;
struct nfs_server *nfss = NFS_SB(mnt->mnt_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_printf(m, "\n\topts:\t");
seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
nfs_show_mount_options(m, nfss, 1);
seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
seq_printf(m, "\n\tcaps:\t");
seq_printf(m, "caps=0x%x", nfss->caps);
seq_printf(m, ",wtmult=%d", nfss->wtmult);
seq_printf(m, ",dtsize=%d", nfss->dtsize);
seq_printf(m, ",bsize=%d", nfss->bsize);
seq_printf(m, ",namelen=%d", nfss->namelen);
#ifdef CONFIG_NFS_V4
if (nfss->nfs_client->cl_nfsversion == 4) {
seq_printf(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, ",acl=0x%x", nfss->acl_bitmask);
}
#endif
/*
* Display security flavor in effect for this mount
*/
seq_printf(m, "\n\tsec:\tflavor=%d", auth->au_ops->au_flavor);
if (auth->au_flavor)
seq_printf(m, ",pseudoflavor=%d", 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];
preempt_enable();
}
seq_printf(m, "\n\tevents:\t");
for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
seq_printf(m, "%lu ", totals.events[i]);
seq_printf(m, "\n\tbytes:\t");
for (i = 0; i < __NFSIOS_BYTESMAX; i++)
seq_printf(m, "%Lu ", totals.bytes[i]);
seq_printf(m, "\n");
rpc_print_iostats(m, nfss->client);
return 0;
}
/*
* Begin unmount by attempting to remove all automounted mountpoints we added
* in response to xdev traversals and referrals
*/
static void nfs_umount_begin(struct vfsmount *vfsmnt, int flags)
{
shrink_submounts(vfsmnt, &nfs_automount_list);
}
/*
* Validate the NFS2/NFS3 mount data
* - fills in the mount root filehandle
*/
static int nfs_validate_mount_data(struct nfs_mount_data *data,
struct nfs_fh *mntfh)
{
if (data == NULL) {
dprintk("%s: missing data argument\n", __FUNCTION__);
return -EINVAL;
}
if (data->version <= 0 || data->version > NFS_MOUNT_VERSION) {
dprintk("%s: bad mount version\n", __FUNCTION__);
return -EINVAL;
}
switch (data->version) {
case 1:
data->namlen = 0;
case 2:
data->bsize = 0;
case 3:
if (data->flags & NFS_MOUNT_VER3) {
dprintk("%s: mount structure version %d does not support NFSv3\n",
__FUNCTION__,
data->version);
return -EINVAL;
}
data->root.size = NFS2_FHSIZE;
memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
case 4:
if (data->flags & NFS_MOUNT_SECFLAVOUR) {
dprintk("%s: mount structure version %d does not support strong security\n",
__FUNCTION__,
data->version);
return -EINVAL;
}
case 5:
memset(data->context, 0, sizeof(data->context));
}
/* Set the pseudoflavor */
if (!(data->flags & NFS_MOUNT_SECFLAVOUR))
data->pseudoflavor = RPC_AUTH_UNIX;
#ifndef CONFIG_NFS_V3
/* If NFSv3 is not compiled in, return -EPROTONOSUPPORT */
if (data->flags & NFS_MOUNT_VER3) {
dprintk("%s: NFSv3 not compiled into kernel\n", __FUNCTION__);
return -EPROTONOSUPPORT;
}
#endif /* CONFIG_NFS_V3 */
/* We now require that the mount process passes the remote address */
if (data->addr.sin_addr.s_addr == INADDR_ANY) {
dprintk("%s: mount program didn't pass remote address!\n",
__FUNCTION__);
return -EINVAL;
}
/* Prepare the root filehandle */
if (data->flags & NFS_MOUNT_VER3)
mntfh->size = data->root.size;
else
mntfh->size = NFS2_FHSIZE;
if (mntfh->size > sizeof(mntfh->data)) {
dprintk("%s: invalid root filehandle\n", __FUNCTION__);
return -EINVAL;
}
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);
return 0;
}
/*
* Initialise the common bits of the superblock
*/
static inline 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),
"%x:%x", 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);
if (server->flags & NFS_MOUNT_NOAC)
sb->s_flags |= MS_SYNCHRONOUS;
nfs_super_set_maxbytes(sb, server->maxfilesize);
}
/*
* Finish setting up an NFS2/3 superblock
*/
static void nfs_fill_super(struct super_block *sb, struct nfs_mount_data *data)
{
struct nfs_server *server = NFS_SB(sb);
sb->s_blocksize_bits = 0;
sb->s_blocksize = 0;
if (data->bsize)
sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
if (server->flags & NFS_MOUNT_VER3) {
/* The VFS shouldn't apply the umask to mode bits. We will do
* so ourselves when necessary.
*/
sb->s_flags |= MS_POSIXACL;
sb->s_time_gran = 1;
}
sb->s_op = &nfs_sops;
nfs_initialise_sb(sb);
}
/*
* Finish setting up a cloned NFS2/3 superblock
*/
static void nfs_clone_super(struct super_block *sb,
const struct super_block *old_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;
if (server->flags & NFS_MOUNT_VER3) {
/* The VFS shouldn't apply the umask to mode bits. We will do
* so ourselves when necessary.
*/
sb->s_flags |= MS_POSIXACL;
sb->s_time_gran = 1;
}
sb->s_op = old_sb->s_op;
nfs_initialise_sb(sb);
}
static int nfs_set_super(struct super_block *s, void *_server)
{
struct nfs_server *server = _server;
int ret;
s->s_fs_info = server;
ret = set_anon_super(s, server);
if (ret == 0)
server->s_dev = s->s_dev;
return ret;
}
static int nfs_compare_super(struct super_block *sb, void *data)
{
struct nfs_server *server = data, *old = NFS_SB(sb);
if (old->nfs_client != server->nfs_client)
return 0;
if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
return 0;
return 1;
}
static int nfs_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
{
struct nfs_server *server = NULL;
struct super_block *s;
struct nfs_fh mntfh;
struct nfs_mount_data *data = raw_data;
struct dentry *mntroot;
int error;
/* Validate the mount data */
error = nfs_validate_mount_data(data, &mntfh);
if (error < 0)
return error;
/* Get a volume representation */
server = nfs_create_server(data, &mntfh);
if (IS_ERR(server)) {
error = PTR_ERR(server);
goto out_err_noserver;
}
/* Get a superblock - note that we may end up sharing one that already exists */
s = sget(fs_type, nfs_compare_super, nfs_set_super, server);
if (IS_ERR(s)) {
error = PTR_ERR(s);
goto out_err_nosb;
}
if (s->s_fs_info != server) {
nfs_free_server(server);
server = NULL;
}
if (!s->s_root) {
/* initial superblock/root creation */
s->s_flags = flags;
nfs_fill_super(s, data);
}
mntroot = nfs_get_root(s, &mntfh);
if (IS_ERR(mntroot)) {
error = PTR_ERR(mntroot);
goto error_splat_super;
}
s->s_flags |= MS_ACTIVE;
mnt->mnt_sb = s;
mnt->mnt_root = mntroot;
return 0;
out_err_nosb:
nfs_free_server(server);
out_err_noserver:
return error;
error_splat_super:
up_write(&s->s_umount);
deactivate_super(s);
return error;
}
/*
* Destroy an NFS2/3 superblock
*/
static void nfs_kill_super(struct super_block *s)
{
struct nfs_server *server = NFS_SB(s);
kill_anon_super(s);
nfs_free_server(server);
}
/*
* Clone an NFS2/3 server record on xdev traversal (FSID-change)
*/
static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
const char *dev_name, void *raw_data,
struct vfsmount *mnt)
{
struct nfs_clone_mount *data = raw_data;
struct super_block *s;
struct nfs_server *server;
struct dentry *mntroot;
int error;
dprintk("--> nfs_xdev_get_sb()\n");
/* create a new volume representation */
server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
if (IS_ERR(server)) {
error = PTR_ERR(server);
goto out_err_noserver;
}
/* Get a superblock - note that we may end up sharing one that already exists */
s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server);
if (IS_ERR(s)) {
error = PTR_ERR(s);
goto out_err_nosb;
}
if (s->s_fs_info != server) {
nfs_free_server(server);
server = NULL;
}
if (!s->s_root) {
/* initial superblock/root creation */
s->s_flags = flags;
nfs_clone_super(s, data->sb);
}
mntroot = nfs_get_root(s, data->fh);
if (IS_ERR(mntroot)) {
error = PTR_ERR(mntroot);
goto error_splat_super;
}
s->s_flags |= MS_ACTIVE;
mnt->mnt_sb = s;
mnt->mnt_root = mntroot;
dprintk("<-- nfs_xdev_get_sb() = 0\n");
return 0;
out_err_nosb:
nfs_free_server(server);
out_err_noserver:
dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
return error;
error_splat_super:
up_write(&s->s_umount);
deactivate_super(s);
dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
return error;
}
#ifdef CONFIG_NFS_V4
/*
* Finish setting up a cloned NFS4 superblock
*/
static void nfs4_clone_super(struct super_block *sb,
const struct super_block *old_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_time_gran = 1;
sb->s_op = old_sb->s_op;
nfs_initialise_sb(sb);
}
/*
* Set up an NFS4 superblock
*/
static void nfs4_fill_super(struct super_block *sb)
{
sb->s_time_gran = 1;
sb->s_op = &nfs4_sops;
nfs_initialise_sb(sb);
}
static void *nfs_copy_user_string(char *dst, struct nfs_string *src, int maxlen)
{
void *p = NULL;
if (!src->len)
return ERR_PTR(-EINVAL);
if (src->len < maxlen)
maxlen = src->len;
if (dst == NULL) {
p = dst = kmalloc(maxlen + 1, GFP_KERNEL);
if (p == NULL)
return ERR_PTR(-ENOMEM);
}
if (copy_from_user(dst, src->data, maxlen)) {
kfree(p);
return ERR_PTR(-EFAULT);
}
dst[maxlen] = '\0';
return dst;
}
/*
* Get the superblock for an NFS4 mountpoint
*/
static int nfs4_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
{
struct nfs4_mount_data *data = raw_data;
struct super_block *s;
struct nfs_server *server;
struct sockaddr_in addr;
rpc_authflavor_t authflavour;
struct nfs_fh mntfh;
struct dentry *mntroot;
char *mntpath = NULL, *hostname = NULL, ip_addr[16];
void *p;
int error;
if (data == NULL) {
dprintk("%s: missing data argument\n", __FUNCTION__);
return -EINVAL;
}
if (data->version <= 0 || data->version > NFS4_MOUNT_VERSION) {
dprintk("%s: bad mount version\n", __FUNCTION__);
return -EINVAL;
}
/* We now require that the mount process passes the remote address */
if (data->host_addrlen != sizeof(addr))
return -EINVAL;
if (copy_from_user(&addr, data->host_addr, sizeof(addr)))
return -EFAULT;
if (addr.sin_family != AF_INET ||
addr.sin_addr.s_addr == INADDR_ANY
) {
dprintk("%s: mount program didn't pass remote IP address!\n",
__FUNCTION__);
return -EINVAL;
}
/* RFC3530: The default port for NFS is 2049 */
if (addr.sin_port == 0)
addr.sin_port = htons(NFS_PORT);
/* Grab the authentication type */
authflavour = RPC_AUTH_UNIX;
if (data->auth_flavourlen != 0) {
if (data->auth_flavourlen != 1) {
dprintk("%s: Invalid number of RPC auth flavours %d.\n",
__FUNCTION__, data->auth_flavourlen);
error = -EINVAL;
goto out_err_noserver;
}
if (copy_from_user(&authflavour, data->auth_flavours,
sizeof(authflavour))) {
error = -EFAULT;
goto out_err_noserver;
}
}
p = nfs_copy_user_string(NULL, &data->hostname, 256);
if (IS_ERR(p))
goto out_err;
hostname = p;
p = nfs_copy_user_string(NULL, &data->mnt_path, 1024);
if (IS_ERR(p))
goto out_err;
mntpath = p;
dprintk("MNTPATH: %s\n", mntpath);
p = nfs_copy_user_string(ip_addr, &data->client_addr,
sizeof(ip_addr) - 1);
if (IS_ERR(p))
goto out_err;
/* Get a volume representation */
server = nfs4_create_server(data, hostname, &addr, mntpath, ip_addr,
authflavour, &mntfh);
if (IS_ERR(server)) {
error = PTR_ERR(server);
goto out_err_noserver;
}
/* Get a superblock - note that we may end up sharing one that already exists */
s = sget(fs_type, nfs_compare_super, nfs_set_super, server);
if (IS_ERR(s)) {
error = PTR_ERR(s);
goto out_free;
}
if (s->s_fs_info != server) {
nfs_free_server(server);
server = NULL;
}
if (!s->s_root) {
/* initial superblock/root creation */
s->s_flags = flags;
nfs4_fill_super(s);
}
mntroot = nfs4_get_root(s, &mntfh);
if (IS_ERR(mntroot)) {
error = PTR_ERR(mntroot);
goto error_splat_super;
}
s->s_flags |= MS_ACTIVE;
mnt->mnt_sb = s;
mnt->mnt_root = mntroot;
kfree(mntpath);
kfree(hostname);
return 0;
out_err:
error = PTR_ERR(p);
goto out_err_noserver;
out_free:
nfs_free_server(server);
out_err_noserver:
kfree(mntpath);
kfree(hostname);
return error;
error_splat_super:
up_write(&s->s_umount);
deactivate_super(s);
goto out_err_noserver;
}
static void nfs4_kill_super(struct super_block *sb)
{
struct nfs_server *server = NFS_SB(sb);
nfs_return_all_delegations(sb);
kill_anon_super(sb);
nfs4_renewd_prepare_shutdown(server);
nfs_free_server(server);
}
/*
* Clone an NFS4 server record on xdev traversal (FSID-change)
*/
static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
const char *dev_name, void *raw_data,
struct vfsmount *mnt)
{
struct nfs_clone_mount *data = raw_data;
struct super_block *s;
struct nfs_server *server;
struct dentry *mntroot;
int error;
dprintk("--> nfs4_xdev_get_sb()\n");
/* create a new volume representation */
server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
if (IS_ERR(server)) {
error = PTR_ERR(server);
goto out_err_noserver;
}
/* Get a superblock - note that we may end up sharing one that already exists */
s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server);
if (IS_ERR(s)) {
error = PTR_ERR(s);
goto out_err_nosb;
}
if (s->s_fs_info != server) {
nfs_free_server(server);
server = NULL;
}
if (!s->s_root) {
/* initial superblock/root creation */
s->s_flags = flags;
nfs4_clone_super(s, data->sb);
}
mntroot = nfs4_get_root(s, data->fh);
if (IS_ERR(mntroot)) {
error = PTR_ERR(mntroot);
goto error_splat_super;
}
s->s_flags |= MS_ACTIVE;
mnt->mnt_sb = s;
mnt->mnt_root = mntroot;
dprintk("<-- nfs4_xdev_get_sb() = 0\n");
return 0;
out_err_nosb:
nfs_free_server(server);
out_err_noserver:
dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
return error;
error_splat_super:
up_write(&s->s_umount);
deactivate_super(s);
dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
return error;
}
/*
* Create an NFS4 server record on referral traversal
*/
static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
const char *dev_name, void *raw_data,
struct vfsmount *mnt)
{
struct nfs_clone_mount *data = raw_data;
struct super_block *s;
struct nfs_server *server;
struct dentry *mntroot;
struct nfs_fh mntfh;
int error;
dprintk("--> nfs4_referral_get_sb()\n");
/* create a new volume representation */
server = nfs4_create_referral_server(data, &mntfh);
if (IS_ERR(server)) {
error = PTR_ERR(server);
goto out_err_noserver;
}
/* Get a superblock - note that we may end up sharing one that already exists */
s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server);
if (IS_ERR(s)) {
error = PTR_ERR(s);
goto out_err_nosb;
}
if (s->s_fs_info != server) {
nfs_free_server(server);
server = NULL;
}
if (!s->s_root) {
/* initial superblock/root creation */
s->s_flags = flags;
nfs4_fill_super(s);
}
mntroot = nfs4_get_root(s, &mntfh);
if (IS_ERR(mntroot)) {
error = PTR_ERR(mntroot);
goto error_splat_super;
}
s->s_flags |= MS_ACTIVE;
mnt->mnt_sb = s;
mnt->mnt_root = mntroot;
dprintk("<-- nfs4_referral_get_sb() = 0\n");
return 0;
out_err_nosb:
nfs_free_server(server);
out_err_noserver:
dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
return error;
error_splat_super:
up_write(&s->s_umount);
deactivate_super(s);
dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
return error;
}
#endif /* CONFIG_NFS_V4 */