super.c 61.7 KB
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/*
 *  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>
 *
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 * - 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())
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 */

#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>
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#include <linux/sunrpc/xprtsock.h>
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#include <linux/sunrpc/xprtrdma.h>
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#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>
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#include <linux/in6.h>
#include <net/ipv6.h>
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#include <linux/netdevice.h>
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#include <linux/nfs_xdr.h>
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#include <linux/magic.h>
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#include <linux/parser.h>
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#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

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enum {
	/* Mount options that take no arguments */
	Opt_soft, Opt_hard,
	Opt_posix, Opt_noposix,
	Opt_cto, Opt_nocto,
	Opt_ac, Opt_noac,
	Opt_lock, Opt_nolock,
	Opt_v2, Opt_v3,
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	Opt_udp, Opt_tcp, Opt_rdma,
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	Opt_acl, Opt_noacl,
	Opt_rdirplus, Opt_nordirplus,
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	Opt_sharecache, Opt_nosharecache,
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	/* 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,
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	Opt_mountvers,
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	Opt_nfsvers,
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	/* Mount options that take string arguments */
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	Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
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	Opt_addr, Opt_mountaddr, Opt_clientaddr,
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	/* Mount options that are ignored */
	Opt_userspace, Opt_deprecated,

	Opt_err
};

static match_table_t nfs_mount_option_tokens = {
	{ Opt_userspace, "bg" },
	{ Opt_userspace, "fg" },
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	{ Opt_userspace, "retry=%s" },

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	{ Opt_soft, "soft" },
	{ Opt_hard, "hard" },
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	{ Opt_deprecated, "intr" },
	{ Opt_deprecated, "nointr" },
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	{ 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_v2, "v2" },
	{ Opt_v3, "v3" },
	{ Opt_udp, "udp" },
	{ Opt_tcp, "tcp" },
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	{ Opt_rdma, "rdma" },
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	{ Opt_acl, "acl" },
	{ Opt_noacl, "noacl" },
	{ Opt_rdirplus, "rdirplus" },
	{ Opt_nordirplus, "nordirplus" },
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	{ Opt_sharecache, "sharecache" },
	{ Opt_nosharecache, "nosharecache" },
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	{ Opt_port, "port=%u" },
	{ Opt_rsize, "rsize=%u" },
	{ Opt_wsize, "wsize=%u" },
	{ Opt_bsize, "bsize=%u" },
	{ Opt_timeo, "timeo=%u" },
	{ Opt_retrans, "retrans=%u" },
	{ Opt_acregmin, "acregmin=%u" },
	{ Opt_acregmax, "acregmax=%u" },
	{ Opt_acdirmin, "acdirmin=%u" },
	{ Opt_acdirmax, "acdirmax=%u" },
	{ Opt_actimeo, "actimeo=%u" },
	{ Opt_namelen, "namlen=%u" },
	{ Opt_mountport, "mountport=%u" },
	{ Opt_mountvers, "mountvers=%u" },
	{ Opt_nfsvers, "nfsvers=%u" },
	{ Opt_nfsvers, "vers=%u" },

	{ Opt_sec, "sec=%s" },
	{ Opt_proto, "proto=%s" },
	{ Opt_mountproto, "mountproto=%s" },
	{ Opt_addr, "addr=%s" },
	{ Opt_clientaddr, "clientaddr=%s" },
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	{ Opt_mounthost, "mounthost=%s" },
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	{ Opt_mountaddr, "mountaddr=%s" },
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	{ Opt_err, NULL }
};

enum {
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	Opt_xprt_udp, Opt_xprt_tcp, Opt_xprt_rdma,
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	Opt_xprt_err
};

static match_table_t nfs_xprt_protocol_tokens = {
	{ Opt_xprt_udp, "udp" },
	{ Opt_xprt_tcp, "tcp" },
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	{ Opt_xprt_rdma, "rdma" },
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	{ 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 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" },

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	{ Opt_sec_spkm, "spkm3" },
	{ Opt_sec_spkmi, "spkm3i" },
	{ Opt_sec_spkmp, "spkm3p" },

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	{ Opt_sec_err, NULL }
};


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static void nfs_umount_begin(struct super_block *);
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static int  nfs_statfs(struct dentry *, struct kstatfs *);
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static int  nfs_show_options(struct seq_file *, struct vfsmount *);
static int  nfs_show_stats(struct seq_file *, struct vfsmount *);
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static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
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static int nfs_xdev_get_sb(struct file_system_type *fs_type,
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		int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
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static void nfs_kill_super(struct super_block *);
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static void nfs_put_super(struct super_block *);
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static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
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static struct file_system_type nfs_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "nfs",
	.get_sb		= nfs_get_sb,
	.kill_sb	= nfs_kill_super,
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	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
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};

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struct file_system_type nfs_xdev_fs_type = {
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	.owner		= THIS_MODULE,
	.name		= "nfs",
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	.get_sb		= nfs_xdev_get_sb,
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	.kill_sb	= nfs_kill_super,
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	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
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};

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static const struct super_operations nfs_sops = {
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	.alloc_inode	= nfs_alloc_inode,
	.destroy_inode	= nfs_destroy_inode,
	.write_inode	= nfs_write_inode,
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	.put_super	= nfs_put_super,
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	.statfs		= nfs_statfs,
	.clear_inode	= nfs_clear_inode,
	.umount_begin	= nfs_umount_begin,
	.show_options	= nfs_show_options,
	.show_stats	= nfs_show_stats,
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	.remount_fs	= nfs_remount,
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};

#ifdef CONFIG_NFS_V4
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static int nfs4_get_sb(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
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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);
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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,
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	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
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};

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struct file_system_type nfs4_xdev_fs_type = {
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	.owner		= THIS_MODULE,
	.name		= "nfs4",
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	.get_sb		= nfs4_xdev_get_sb,
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	.kill_sb	= nfs4_kill_super,
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	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
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};

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struct file_system_type nfs4_referral_fs_type = {
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	.owner		= THIS_MODULE,
	.name		= "nfs4",
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	.get_sb		= nfs4_referral_get_sb,
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	.kill_sb	= nfs4_kill_super,
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	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
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};

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static const struct super_operations nfs4_sops = {
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	.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,
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	.remount_fs	= nfs_remount,
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};
#endif

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static struct shrinker acl_shrinker = {
	.shrink		= nfs_access_cache_shrinker,
	.seeks		= DEFAULT_SEEKS,
};
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/*
 * 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;
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#ifdef CONFIG_NFS_V4
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	ret = register_filesystem(&nfs4_fs_type);
	if (ret < 0)
		goto error_2;
#endif
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	register_shrinker(&acl_shrinker);
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	return 0;

#ifdef CONFIG_NFS_V4
error_2:
	nfs_unregister_sysctl();
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#endif
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error_1:
	unregister_filesystem(&nfs_fs_type);
error_0:
	return ret;
}

/*
 * Unregister the NFS filesystems
 */
void __exit unregister_nfs_fs(void)
{
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	unregister_shrinker(&acl_shrinker);
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#ifdef CONFIG_NFS_V4
	unregister_filesystem(&nfs4_fs_type);
#endif
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	nfs_unregister_sysctl();
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	unregister_filesystem(&nfs_fs_type);
}

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void nfs_sb_active(struct nfs_server *server)
{
	atomic_inc(&server->active);
}

void nfs_sb_deactive(struct nfs_server *server)
{
	if (atomic_dec_and_test(&server->active))
		wake_up(&server->active_wq);
}

static void nfs_put_super(struct super_block *sb)
{
	struct nfs_server *server = NFS_SB(sb);
	/*
	 * Make sure there are no outstanding ops to this server.
	 * If so, wait for them to finish before allowing the
	 * unmount to continue.
	 */
	wait_event(server->active_wq, atomic_read(&server->active) == 0);
}

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/*
 * Deliver file system statistics to userspace
 */
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static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
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{
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	struct nfs_server *server = NFS_SB(dentry->d_sb);
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	unsigned char blockbits;
	unsigned long blockres;
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	struct nfs_fh *fh = NFS_FH(dentry->d_inode);
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	struct nfs_fattr fattr;
	struct nfs_fsstat res = {
			.fattr = &fattr,
	};
	int error;

	lock_kernel();

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	error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
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	if (error < 0)
		goto out_err;
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	buf->f_type = NFS_SUPER_MAGIC;
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	/*
	 * 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.
	 */
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	buf->f_frsize = dentry->d_sb->s_blocksize;
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	/*
	 * 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.
	 */
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	buf->f_bsize = dentry->d_sb->s_blocksize;
	blockbits = dentry->d_sb->s_blocksize_bits;
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	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;
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	unlock_kernel();
	return 0;

 out_err:
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	dprintk("%s: statfs error = %d\n", __func__, -error);
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	unlock_kernel();
	return error;
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}

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/*
 * Map the security flavour number to a name
 */
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static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
{
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	static const struct {
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		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" },
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		{ UINT_MAX, "unknown" }
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	};
	int i;

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	for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
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		if (sec_flavours[i].flavour == flavour)
			break;
	}
	return sec_flavours[i].str;
}

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static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
				    int showdefaults)
{
	struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;

	switch (sap->sa_family) {
	case AF_INET: {
		struct sockaddr_in *sin = (struct sockaddr_in *)sap;
		seq_printf(m, ",mountaddr=" NIPQUAD_FMT,
				NIPQUAD(sin->sin_addr.s_addr));
		break;
	}
	case AF_INET6: {
		struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
		seq_printf(m, ",mountaddr=" NIP6_FMT,
				NIP6(sin6->sin6_addr));
		break;
	}
	default:
		if (showdefaults)
			seq_printf(m, ",mountaddr=unspecified");
	}

	if (nfss->mountd_version || showdefaults)
		seq_printf(m, ",mountvers=%u", nfss->mountd_version);
	if (nfss->mountd_port || showdefaults)
		seq_printf(m, ",mountport=%u", nfss->mountd_port);

	switch (nfss->mountd_protocol) {
	case IPPROTO_UDP:
		seq_printf(m, ",mountproto=udp");
		break;
	case IPPROTO_TCP:
		seq_printf(m, ",mountproto=tcp");
		break;
	default:
		if (showdefaults)
			seq_printf(m, ",mountproto=auto");
	}
}

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/*
 * Describe the mount options in force on this server representation
 */
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static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
				   int showdefaults)
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{
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	static const struct proc_nfs_info {
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		int flag;
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		const char *str;
		const char *nostr;
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	} nfs_info[] = {
		{ NFS_MOUNT_SOFT, ",soft", ",hard" },
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		{ NFS_MOUNT_INTR, ",intr", ",nointr" },
		{ NFS_MOUNT_POSIX, ",posix", "" },
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		{ NFS_MOUNT_NOCTO, ",nocto", "" },
		{ NFS_MOUNT_NOAC, ",noac", "" },
		{ NFS_MOUNT_NONLM, ",nolock", "" },
		{ NFS_MOUNT_NOACL, ",noacl", "" },
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		{ NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
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		{ NFS_MOUNT_UNSHARED, ",nosharecache", ""},
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		{ 0, NULL, NULL }
	};
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	const struct proc_nfs_info *nfs_infop;
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	struct nfs_client *clp = nfss->nfs_client;
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	u32 version = clp->rpc_ops->version;
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	seq_printf(m, ",vers=%u", version);
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	seq_printf(m, ",rsize=%u", nfss->rsize);
	seq_printf(m, ",wsize=%u", nfss->wsize);
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	if (nfss->bsize != 0)
		seq_printf(m, ",bsize=%u", nfss->bsize);
	seq_printf(m, ",namlen=%u", nfss->namelen);
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	if (nfss->acregmin != 3*HZ || showdefaults)
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		seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
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	if (nfss->acregmax != 60*HZ || showdefaults)
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		seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
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	if (nfss->acdirmin != 30*HZ || showdefaults)
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		seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
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	if (nfss->acdirmax != 60*HZ || showdefaults)
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		seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
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	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);
	}
535 536
	seq_printf(m, ",proto=%s",
		   rpc_peeraddr2str(nfss->client, RPC_DISPLAY_PROTO));
537 538 539 540 541 542 543
	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);

544 545
	seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
	seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
546
	seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
547 548 549 550 551 552 553 554

	if (version != 4)
		nfs_show_mountd_options(m, nfss, showdefaults);

#ifdef CONFIG_NFS_V4
	if (clp->rpc_ops->version == 4)
		seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
#endif
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}

/*
 * 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);

566 567 568
	seq_printf(m, ",addr=%s",
			rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
							RPC_DISPLAY_ADDR));
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	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);
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	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);
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#ifdef CONFIG_NFS_V4
605
	if (nfss->nfs_client->rpc_ops->version == 4) {
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		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
	 */
616
	seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
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	if (auth->au_flavor)
618
		seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
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	/*
	 * 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
652
 * in response to xdev traversals and referrals
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 */
654
static void nfs_umount_begin(struct super_block *sb)
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{
656
	struct nfs_server *server = NFS_SB(sb);
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	struct rpc_clnt *rpc;

	/* -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);
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}

668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686
/*
 * Set the port number in an address.  Be agnostic about the address family.
 */
static void nfs_set_port(struct sockaddr *sap, unsigned short port)
{
	switch (sap->sa_family) {
	case AF_INET: {
		struct sockaddr_in *ap = (struct sockaddr_in *)sap;
		ap->sin_port = htons(port);
		break;
	}
	case AF_INET6: {
		struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
		ap->sin6_port = htons(port);
		break;
	}
	}
}

687
/*
688 689 690 691
 * 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.
692 693 694 695 696
 */
static int nfs_verify_server_address(struct sockaddr *addr)
{
	switch (addr->sa_family) {
	case AF_INET: {
697
		struct sockaddr_in *sa = (struct sockaddr_in *)addr;
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		return sa->sin_addr.s_addr != htonl(INADDR_ANY);
699 700 701 702
	}
	case AF_INET6: {
		struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
		return !ipv6_addr_any(sa);
703 704 705 706 707 708
	}
	}

	return 0;
}

709 710
static void nfs_parse_ipv4_address(char *string, size_t str_len,
				   struct sockaddr *sap, size_t *addr_len)
711
{
712 713
	struct sockaddr_in *sin = (struct sockaddr_in *)sap;
	u8 *addr = (u8 *)&sin->sin_addr.s_addr;
714

715 716 717 718 719 720 721
	if (str_len <= INET_ADDRSTRLEN) {
		dfprintk(MOUNT, "NFS: parsing IPv4 address %*s\n",
				(int)str_len, string);

		sin->sin_family = AF_INET;
		*addr_len = sizeof(*sin);
		if (in4_pton(string, str_len, addr, '\0', NULL))
722
			return;
723 724 725 726 727 728
	}

	sap->sa_family = AF_UNSPEC;
	*addr_len = 0;
}

729 730
#define IPV6_SCOPE_DELIMITER	'%'

731
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
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static void nfs_parse_ipv6_scope_id(const char *string, const size_t str_len,
				    const char *delim,
				    struct sockaddr_in6 *sin6)
{
	char *p;
	size_t len;

	if (!(ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL))
		return ;
	if (*delim != IPV6_SCOPE_DELIMITER)
		return;

	len = (string + str_len) - delim - 1;
	p = kstrndup(delim + 1, len, GFP_KERNEL);
	if (p) {
		unsigned long scope_id = 0;
		struct net_device *dev;

		dev = dev_get_by_name(&init_net, p);
		if (dev != NULL) {
			scope_id = dev->ifindex;
			dev_put(dev);
		} else {
			/* scope_id is set to zero on error */
			strict_strtoul(p, 10, &scope_id);
		}

		kfree(p);
		sin6->sin6_scope_id = scope_id;
		dfprintk(MOUNT, "NFS: IPv6 scope ID = %lu\n", scope_id);
	}
}

765 766 767 768 769
static void nfs_parse_ipv6_address(char *string, size_t str_len,
				   struct sockaddr *sap, size_t *addr_len)
{
	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
	u8 *addr = (u8 *)&sin6->sin6_addr.in6_u;
770
	const char *delim;
771 772 773 774

	if (str_len <= INET6_ADDRSTRLEN) {
		dfprintk(MOUNT, "NFS: parsing IPv6 address %*s\n",
				(int)str_len, string);
775

776 777
		sin6->sin6_family = AF_INET6;
		*addr_len = sizeof(*sin6);
778 779
		if (in6_pton(string, str_len, addr, IPV6_SCOPE_DELIMITER, &delim)) {
			nfs_parse_ipv6_scope_id(string, str_len, delim, sin6);
780
			return;
781
		}
782
	}
783 784

	sap->sa_family = AF_UNSPEC;
785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816
	*addr_len = 0;
}
#else
static void nfs_parse_ipv6_address(char *string, size_t str_len,
				   struct sockaddr *sap, size_t *addr_len)
{
	sap->sa_family = AF_UNSPEC;
	*addr_len = 0;
}
#endif

/*
 * Construct a sockaddr based on the contents of a string that contains
 * an IP address in presentation format.
 *
 * If there is a problem constructing the new sockaddr, set the address
 * family to AF_UNSPEC.
 */
static void nfs_parse_ip_address(char *string, size_t str_len,
				 struct sockaddr *sap, size_t *addr_len)
{
	unsigned int i, colons;

	colons = 0;
	for (i = 0; i < str_len; i++)
		if (string[i] == ':')
			colons++;

	if (colons >= 2)
		nfs_parse_ipv6_address(string, str_len, sap, addr_len);
	else
		nfs_parse_ipv4_address(string, str_len, sap, addr_len);
817 818
}

819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855
/*
 * 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;
	}
}

856 857 858 859 860 861 862
/*
 * Error-check and convert a string of mount options from user space into
 * a data structure
 */
static int nfs_parse_mount_options(char *raw,
				   struct nfs_parsed_mount_data *mnt)
{
863 864
	char *p, *string, *secdata;
	int rc;
865 866 867 868 869 870 871

	if (!raw) {
		dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
		return 1;
	}
	dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);

872 873 874 875 876 877 878 879 880 881 882 883 884 885
	secdata = alloc_secdata();
	if (!secdata)
		goto out_nomem;

	rc = security_sb_copy_data(raw, secdata);
	if (rc)
		goto out_security_failure;

	rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
	if (rc)
		goto out_security_failure;

	free_secdata(secdata);

886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934
	while ((p = strsep(&raw, ",")) != NULL) {
		substring_t args[MAX_OPT_ARGS];
		int option, 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) {
		case Opt_soft:
			mnt->flags |= NFS_MOUNT_SOFT;
			break;
		case Opt_hard:
			mnt->flags &= ~NFS_MOUNT_SOFT;
			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;
			break;
		case Opt_nolock:
			mnt->flags |= NFS_MOUNT_NONLM;
			break;
		case Opt_v2:
			mnt->flags &= ~NFS_MOUNT_VER3;
			break;
		case Opt_v3:
			mnt->flags |= NFS_MOUNT_VER3;
			break;
		case Opt_udp:
			mnt->flags &= ~NFS_MOUNT_TCP;
935
			mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
936 937 938
			break;
		case Opt_tcp:
			mnt->flags |= NFS_MOUNT_TCP;
939
			mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
940
			break;
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\"Talpey, Thomas\ 已提交
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		case Opt_rdma:
			mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
			mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
			break;
945 946 947 948 949 950 951 952 953 954 955 956
		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;
957 958 959 960 961 962
		case Opt_sharecache:
			mnt->flags &= ~NFS_MOUNT_UNSHARED;
			break;
		case Opt_nosharecache:
			mnt->flags |= NFS_MOUNT_UNSHARED;
			break;
963 964 965 966 967 968

		case Opt_port:
			if (match_int(args, &option))
				return 0;
			if (option < 0 || option > 65535)
				return 0;
969
			mnt->nfs_server.port = option;
970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133
			break;
		case Opt_rsize:
			if (match_int(args, &mnt->rsize))
				return 0;
			break;
		case Opt_wsize:
			if (match_int(args, &mnt->wsize))
				return 0;
			break;
		case Opt_bsize:
			if (match_int(args, &option))
				return 0;
			if (option < 0)
				return 0;
			mnt->bsize = option;
			break;
		case Opt_timeo:
			if (match_int(args, &mnt->timeo))
				return 0;
			break;
		case Opt_retrans:
			if (match_int(args, &mnt->retrans))
				return 0;
			break;
		case Opt_acregmin:
			if (match_int(args, &mnt->acregmin))
				return 0;
			break;
		case Opt_acregmax:
			if (match_int(args, &mnt->acregmax))
				return 0;
			break;
		case Opt_acdirmin:
			if (match_int(args, &mnt->acdirmin))
				return 0;
			break;
		case Opt_acdirmax:
			if (match_int(args, &mnt->acdirmax))
				return 0;
			break;
		case Opt_actimeo:
			if (match_int(args, &option))
				return 0;
			if (option < 0)
				return 0;
			mnt->acregmin =
			mnt->acregmax =
			mnt->acdirmin =
			mnt->acdirmax = option;
			break;
		case Opt_namelen:
			if (match_int(args, &mnt->namlen))
				return 0;
			break;
		case Opt_mountport:
			if (match_int(args, &option))
				return 0;
			if (option < 0 || option > 65535)
				return 0;
			mnt->mount_server.port = option;
			break;
		case Opt_mountvers:
			if (match_int(args, &option))
				return 0;
			if (option < 0)
				return 0;
			mnt->mount_server.version = option;
			break;
		case Opt_nfsvers:
			if (match_int(args, &option))
				return 0;
			switch (option) {
			case 2:
				mnt->flags &= ~NFS_MOUNT_VER3;
				break;
			case 3:
				mnt->flags |= NFS_MOUNT_VER3;
				break;
			default:
				goto out_unrec_vers;
			}
			break;

		case Opt_sec:
			string = match_strdup(args);
			if (string == NULL)
				goto out_nomem;
			token = match_token(string, nfs_secflavor_tokens, args);
			kfree(string);

			/*
			 * The flags setting is for v2/v3.  The flavor_len
			 * setting is for v4.  v2/v3 also need to know the
			 * difference between NULL and UNIX.
			 */
			switch (token) {
			case Opt_sec_none:
				mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
				mnt->auth_flavor_len = 0;
				mnt->auth_flavors[0] = RPC_AUTH_NULL;
				break;
			case Opt_sec_sys:
				mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
				mnt->auth_flavor_len = 0;
				mnt->auth_flavors[0] = RPC_AUTH_UNIX;
				break;
			case Opt_sec_krb5:
				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
				mnt->auth_flavor_len = 1;
				mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
				break;
			case Opt_sec_krb5i:
				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
				mnt->auth_flavor_len = 1;
				mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
				break;
			case Opt_sec_krb5p:
				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
				mnt->auth_flavor_len = 1;
				mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
				break;
			case Opt_sec_lkey:
				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
				mnt->auth_flavor_len = 1;
				mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
				break;
			case Opt_sec_lkeyi:
				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
				mnt->auth_flavor_len = 1;
				mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
				break;
			case Opt_sec_lkeyp:
				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
				mnt->auth_flavor_len = 1;
				mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
				break;
			case Opt_sec_spkm:
				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
				mnt->auth_flavor_len = 1;
				mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
				break;
			case Opt_sec_spkmi:
				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
				mnt->auth_flavor_len = 1;
				mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
				break;
			case Opt_sec_spkmp:
				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
				mnt->auth_flavor_len = 1;
				mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
				break;
			default:
				goto out_unrec_sec;
			}
			break;
		case Opt_proto:
			string = match_strdup(args);
			if (string == NULL)
				goto out_nomem;
			token = match_token(string,
					    nfs_xprt_protocol_tokens, args);
			kfree(string);

			switch (token) {
1134
			case Opt_xprt_udp:
1135
				mnt->flags &= ~NFS_MOUNT_TCP;
1136
				mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1137
				break;
1138
			case Opt_xprt_tcp:
1139
				mnt->flags |= NFS_MOUNT_TCP;
1140
				mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1141
				break;
\
\"Talpey, Thomas\ 已提交
1142 1143 1144 1145 1146
			case Opt_xprt_rdma:
				/* vector side protocols to TCP */
				mnt->flags |= NFS_MOUNT_TCP;
				mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
				break;
1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159
			default:
				goto out_unrec_xprt;
			}
			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);

			switch (token) {
1160
			case Opt_xprt_udp:
1161
				mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1162
				break;
1163
			case Opt_xprt_tcp:
1164
				mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1165
				break;
\
\"Talpey, Thomas\ 已提交
1166
			case Opt_xprt_rdma: /* not used for side protocols */
1167 1168 1169 1170 1171 1172 1173 1174
			default:
				goto out_unrec_xprt;
			}
			break;
		case Opt_addr:
			string = match_strdup(args);
			if (string == NULL)
				goto out_nomem;
1175 1176 1177 1178
			nfs_parse_ip_address(string, strlen(string),
					     (struct sockaddr *)
						&mnt->nfs_server.address,
					     &mnt->nfs_server.addrlen);
1179 1180 1181 1182 1183 1184
			kfree(string);
			break;
		case Opt_clientaddr:
			string = match_strdup(args);
			if (string == NULL)
				goto out_nomem;
1185
			kfree(mnt->client_address);
1186 1187
			mnt->client_address = string;
			break;
1188 1189 1190 1191
		case Opt_mounthost:
			string = match_strdup(args);
			if (string == NULL)
				goto out_nomem;
1192
			kfree(mnt->mount_server.hostname);
1193 1194
			mnt->mount_server.hostname = string;
			break;
1195
		case Opt_mountaddr:
1196 1197 1198
			string = match_strdup(args);
			if (string == NULL)
				goto out_nomem;
1199 1200 1201 1202
			nfs_parse_ip_address(string, strlen(string),
					     (struct sockaddr *)
						&mnt->mount_server.address,
					     &mnt->mount_server.addrlen);
1203 1204 1205 1206 1207
			kfree(string);
			break;

		case Opt_userspace:
		case Opt_deprecated:
1208 1209
			dfprintk(MOUNT, "NFS:   ignoring mount option "
					"'%s'\n", p);
1210 1211 1212 1213 1214 1215 1216
			break;

		default:
			goto out_unknown;
		}
	}

1217 1218
	nfs_set_port((struct sockaddr *)&mnt->nfs_server.address,
				mnt->nfs_server.port);
1219

1220 1221 1222 1223 1224
	return 1;

out_nomem:
	printk(KERN_INFO "NFS: not enough memory to parse option\n");
	return 0;
1225 1226 1227 1228
out_security_failure:
	free_secdata(secdata);
	printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
	return 0;
1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245
out_unrec_vers:
	printk(KERN_INFO "NFS: unrecognized NFS version number\n");
	return 0;

out_unrec_xprt:
	printk(KERN_INFO "NFS: unrecognized transport protocol\n");
	return 0;

out_unrec_sec:
	printk(KERN_INFO "NFS: unrecognized security flavor\n");
	return 0;

out_unknown:
	printk(KERN_INFO "NFS: unknown mount option: %s\n", p);
	return 0;
}

1246 1247 1248 1249 1250 1251 1252
/*
 * Use the remote server's MOUNT service to request the NFS file handle
 * corresponding to the provided path.
 */
static int nfs_try_mount(struct nfs_parsed_mount_data *args,
			 struct nfs_fh *root_fh)
{
1253
	struct sockaddr *sap = (struct sockaddr *)&args->mount_server.address;
1254
	char *hostname;
1255
	int status;
1256 1257 1258 1259 1260 1261 1262 1263

	if (args->mount_server.version == 0) {
		if (args->flags & NFS_MOUNT_VER3)
			args->mount_server.version = NFS_MNT3_VERSION;
		else
			args->mount_server.version = NFS_MNT_VERSION;
	}

1264 1265 1266 1267 1268
	if (args->mount_server.hostname)
		hostname = args->mount_server.hostname;
	else
		hostname = args->nfs_server.hostname;

1269 1270 1271
	/*
	 * Construct the mount server's address.
	 */
1272 1273 1274 1275 1276 1277
	if (args->mount_server.address.ss_family == AF_UNSPEC) {
		memcpy(sap, &args->nfs_server.address,
		       args->nfs_server.addrlen);
		args->mount_server.addrlen = args->nfs_server.addrlen;
	}

1278 1279 1280
	/*
	 * autobind will be used if mount_server.port == 0
	 */
1281
	nfs_set_port(sap, args->mount_server.port);
1282 1283 1284 1285 1286

	/*
	 * Now ask the mount server to map our export path
	 * to a file handle.
	 */
1287 1288
	status = nfs_mount(sap,
			   args->mount_server.addrlen,
1289
			   hostname,
1290 1291 1292 1293
			   args->nfs_server.export_path,
			   args->mount_server.version,
			   args->mount_server.protocol,
			   root_fh);
1294 1295
	if (status == 0)
		return 0;
1296

1297
	dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1298
			hostname, status);
1299 1300 1301
	return status;
}

1302 1303 1304
static int nfs_parse_simple_hostname(const char *dev_name,
				     char **hostname, size_t maxnamlen,
				     char **export_path, size_t maxpathlen)
1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357
{
	size_t len;
	char *colon, *comma;

	colon = strchr(dev_name, ':');
	if (colon == NULL)
		goto out_bad_devname;

	len = colon - 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)
		goto out_nomem;

	/* kill possible hostname list: not supported */
	comma = strchr(*hostname, ',');
	if (comma != NULL) {
		if (comma == *hostname)
			goto out_bad_devname;
		*comma = '\0';
	}

	colon++;
	len = strlen(colon);
	if (len > maxpathlen)
		goto out_path;
	*export_path = kstrndup(colon, 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;
}

1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436
/*
 * Hostname has square brackets around it because it contains one or
 * more colons.  We look for the first closing square bracket, and a
 * colon must follow it.
 */
static int nfs_parse_protected_hostname(const char *dev_name,
					char **hostname, size_t maxnamlen,
					char **export_path, size_t maxpathlen)
{
	size_t len;
	char *start, *end;

	start = (char *)(dev_name + 1);

	end = strchr(start, ']');
	if (end == NULL)
		goto out_bad_devname;
	if (*(end + 1) != ':')
		goto out_bad_devname;

	len = end - start;
	if (len > maxnamlen)
		goto out_hostname;

	/* N.B. caller will free nfs_server.hostname in all cases */
	*hostname = kstrndup(start, len, GFP_KERNEL);
	if (*hostname == NULL)
		goto out_nomem;

	end += 2;
	len = strlen(end);
	if (len > maxpathlen)
		goto out_path;
	*export_path = kstrndup(end, len, GFP_KERNEL);
	if (!*export_path)
		goto out_nomem;

	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;
}

/*
 * 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)
{
	if (*dev_name == '[')
		return nfs_parse_protected_hostname(dev_name,
						    hostname, maxnamlen,
						    export_path, maxpathlen);

	return nfs_parse_simple_hostname(dev_name,
					 hostname, maxnamlen,
					 export_path, maxpathlen);
}

D
David Howells 已提交
1437
/*
1438 1439
 * Validate the NFS2/NFS3 mount data
 * - fills in the mount root filehandle
1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451
 *
 * 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
D
David Howells 已提交
1452
 */
1453 1454
static int nfs_validate_mount_data(void *options,
				   struct nfs_parsed_mount_data *args,
1455 1456
				   struct nfs_fh *mntfh,
				   const char *dev_name)
D
David Howells 已提交
1457
{
1458
	struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1459

1460 1461
	if (data == NULL)
		goto out_no_data;
D
David Howells 已提交
1462

1463 1464 1465 1466 1467 1468 1469
	args->flags		= (NFS_MOUNT_VER3 | NFS_MOUNT_TCP);
	args->rsize		= NFS_MAX_FILE_IO_SIZE;
	args->wsize		= NFS_MAX_FILE_IO_SIZE;
	args->acregmin		= 3;
	args->acregmax		= 60;
	args->acdirmin		= 30;
	args->acdirmax		= 60;
1470 1471
	args->mount_server.port	= 0;	/* autobind unless user sets port */
	args->nfs_server.port	= 0;	/* autobind unless user sets port */
1472
	args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1473

1474
	switch (data->version) {
1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489
	case 1:
		data->namlen = 0;
	case 2:
		data->bsize = 0;
	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);
	case 4:
		if (data->flags & NFS_MOUNT_SECFLAVOUR)
			goto out_no_sec;
	case 5:
		memset(data->context, 0, sizeof(data->context));
	case 6:
1490 1491 1492
		if (data->flags & NFS_MOUNT_VER3) {
			if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
				goto out_invalid_fh;
1493
			mntfh->size = data->root.size;
1494
		} else
1495 1496 1497 1498 1499 1500 1501
			mntfh->size = NFS2_FHSIZE;


		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);
1502

1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515
		/*
		 * Translate to nfs_parsed_mount_data, which nfs_fill_super
		 * can deal with.
		 */
		args->flags		= data->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;
1516 1517 1518 1519 1520 1521 1522 1523

		memcpy(&args->nfs_server.address, &data->addr,
		       sizeof(data->addr));
		args->nfs_server.addrlen = sizeof(data->addr);
		if (!nfs_verify_server_address((struct sockaddr *)
						&args->nfs_server.address))
			goto out_no_address;

1524
		if (!(data->flags & NFS_MOUNT_TCP))
1525
			args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1526 1527 1528 1529 1530
		/* 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;
		args->auth_flavors[0]	= data->pseudoflavor;
1531 1532
		if (!args->nfs_server.hostname)
			goto out_nomem;
1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559

		/*
		 * 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;
			char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
			if (!opts_str)
				return -ENOMEM;
			strcpy(opts_str, "context=");
			data->context[NFS_MAX_CONTEXT_LEN] = '\0';
			strcat(opts_str, &data->context[0]);
			rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
			kfree(opts_str);
			if (rc)
				return rc;
#else
			return -EINVAL;
#endif
		}

1560
		break;
1561 1562 1563
	default: {
		int status;

1564 1565
		if (nfs_parse_mount_options((char *)options, args) == 0)
			return -EINVAL;
1566

1567 1568 1569 1570
		if (!nfs_verify_server_address((struct sockaddr *)
						&args->nfs_server.address))
			goto out_no_address;

1571 1572
		nfs_set_mount_transport_protocol(args);

1573 1574 1575 1576 1577 1578 1579
		status = nfs_parse_devname(dev_name,
					   &args->nfs_server.hostname,
					   PAGE_SIZE,
					   &args->nfs_server.export_path,
					   NFS_MAXPATHLEN);
		if (!status)
			status = nfs_try_mount(args, mntfh);
1580

1581 1582
		kfree(args->nfs_server.export_path);
		args->nfs_server.export_path = NULL;
1583 1584

		if (status)
1585
			return status;
1586 1587 1588

		break;
		}
D
David Howells 已提交
1589
	}
1590

1591 1592
	if (!(args->flags & NFS_MOUNT_SECFLAVOUR))
		args->auth_flavors[0] = RPC_AUTH_UNIX;
1593

1594
#ifndef CONFIG_NFS_V3
1595
	if (args->flags & NFS_MOUNT_VER3)
1596 1597
		goto out_v3_not_compiled;
#endif /* !CONFIG_NFS_V3 */
D
David Howells 已提交
1598

1599
	return 0;
D
David Howells 已提交
1600

1601 1602 1603
out_no_data:
	dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
	return -EINVAL;
1604

1605 1606 1607 1608
out_no_v3:
	dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
		 data->version);
	return -EINVAL;
D
David Howells 已提交
1609

1610 1611 1612 1613 1614 1615 1616 1617 1618 1619
out_no_sec:
	dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
	return -EINVAL;

#ifndef CONFIG_NFS_V3
out_v3_not_compiled:
	dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
	return -EPROTONOSUPPORT;
#endif /* !CONFIG_NFS_V3 */

1620 1621 1622 1623
out_nomem:
	dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
	return -ENOMEM;

1624 1625 1626 1627 1628 1629 1630
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;
D
David Howells 已提交
1631 1632
}

1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662
static int
nfs_compare_remount_data(struct nfs_server *nfss,
			 struct nfs_parsed_mount_data *data)
{
	if (data->flags != nfss->flags ||
	    data->rsize != nfss->rsize ||
	    data->wsize != nfss->wsize ||
	    data->retrans != nfss->client->cl_timeout->to_retries ||
	    data->auth_flavors[0] != 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.addrlen != nfss->nfs_client->cl_addrlen ||
	    memcmp(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
		   data->nfs_server.addrlen) != 0)
		return -EINVAL;

	return 0;
}

static 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;
1663
	u32 nfsvers = nfss->nfs_client->rpc_ops->version;
1664 1665 1666 1667 1668 1669 1670

	/*
	 * 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.
	 */
1671 1672
	if ((nfsvers == 4 && options4->version == 1) ||
	    (nfsvers <= 3 && options->version >= 1 &&
1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706
	     options->version <= 6))
		return 0;

	data = kzalloc(sizeof(*data), GFP_KERNEL);
	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->auth_flavors[0] = 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.addrlen = nfss->nfs_client->cl_addrlen;
	memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
		data->nfs_server.addrlen);

	/* overwrite those values with any that were specified */
	error = nfs_parse_mount_options((char *)options, data);
	if (error < 0)
		goto out;

	/* compare new mount options with old ones */
	error = nfs_compare_remount_data(nfss, data);
out:
	kfree(data);
	return error;
}

D
David Howells 已提交
1707
/*
1708
 * Initialise the common bits of the superblock
D
David Howells 已提交
1709
 */
1710
static inline void nfs_initialise_sb(struct super_block *sb)
D
David Howells 已提交
1711
{
1712
	struct nfs_server *server = NFS_SB(sb);
1713

1714
	sb->s_magic = NFS_SUPER_MAGIC;
D
David Howells 已提交
1715

1716 1717 1718
	/* 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));
1719

1720 1721 1722
	if (sb->s_blocksize == 0)
		sb->s_blocksize = nfs_block_bits(server->wsize,
						 &sb->s_blocksize_bits);
D
David Howells 已提交
1723

1724 1725
	if (server->flags & NFS_MOUNT_NOAC)
		sb->s_flags |= MS_SYNCHRONOUS;
D
David Howells 已提交
1726

1727
	nfs_super_set_maxbytes(sb, server->maxfilesize);
D
David Howells 已提交
1728 1729 1730
}

/*
1731
 * Finish setting up an NFS2/3 superblock
D
David Howells 已提交
1732
 */
1733 1734
static void nfs_fill_super(struct super_block *sb,
			   struct nfs_parsed_mount_data *data)
D
David Howells 已提交
1735 1736
{
	struct nfs_server *server = NFS_SB(sb);
1737

1738 1739 1740 1741
	sb->s_blocksize_bits = 0;
	sb->s_blocksize = 0;
	if (data->bsize)
		sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
D
David Howells 已提交
1742

1743 1744 1745 1746 1747 1748
	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;
1749
	}
1750 1751 1752

	sb->s_op = &nfs_sops;
 	nfs_initialise_sb(sb);
D
David Howells 已提交
1753 1754 1755
}

/*
1756
 * Finish setting up a cloned NFS2/3 superblock
D
David Howells 已提交
1757
 */
1758 1759
static void nfs_clone_super(struct super_block *sb,
			    const struct super_block *old_sb)
D
David Howells 已提交
1760
{
1761 1762 1763 1764 1765
	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;
D
David Howells 已提交
1766 1767

	if (server->flags & NFS_MOUNT_VER3) {
1768 1769
		/* The VFS shouldn't apply the umask to mode bits. We will do
		 * so ourselves when necessary.
D
David Howells 已提交
1770 1771 1772 1773 1774
		 */
		sb->s_flags |= MS_POSIXACL;
		sb->s_time_gran = 1;
	}

1775 1776
	sb->s_op = old_sb->s_op;
 	nfs_initialise_sb(sb);
D
David Howells 已提交
1777 1778
}

1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806
#define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)

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)
		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;
T
Trond Myklebust 已提交
1807
	return 1;
1808
Ebusy:
T
Trond Myklebust 已提交
1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830
	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;
	ret = set_anon_super(s, server);
	if (ret == 0)
		server->s_dev = s->s_dev;
	return ret;
}

1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867
static int nfs_compare_super_address(struct nfs_server *server1,
				     struct nfs_server *server2)
{
	struct sockaddr *sap1, *sap2;

	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;
}

T
Trond Myklebust 已提交
1868 1869 1870 1871 1872 1873
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;

1874
	if (!nfs_compare_super_address(old, server))
T
Trond Myklebust 已提交
1875 1876 1877 1878 1879 1880 1881
		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;
	return nfs_compare_mount_options(sb, server, mntflags);
1882 1883
}

1884 1885 1886 1887 1888
static int nfs_bdi_register(struct nfs_server *server)
{
	return bdi_register_dev(&server->backing_dev_info, server->s_dev);
}

1889 1890
static int nfs_get_sb(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
D
David Howells 已提交
1891 1892 1893
{
	struct nfs_server *server = NULL;
	struct super_block *s;
1894 1895
	struct nfs_parsed_mount_data *data;
	struct nfs_fh *mntfh;
1896
	struct dentry *mntroot;
1897
	int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
T
Trond Myklebust 已提交
1898 1899 1900
	struct nfs_sb_mountdata sb_mntdata = {
		.mntflags = flags,
	};
1901 1902 1903 1904 1905 1906
	int error = -ENOMEM;

	data = kzalloc(sizeof(*data), GFP_KERNEL);
	mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
	if (data == NULL || mntfh == NULL)
		goto out_free_fh;
D
David Howells 已提交
1907

1908
	security_init_mnt_opts(&data->lsm_opts);
1909

1910
	/* Validate the mount data */
1911
	error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
1912
	if (error < 0)
1913
		goto out;
D
David Howells 已提交
1914

1915
	/* Get a volume representation */
1916
	server = nfs_create_server(data, mntfh);
1917 1918
	if (IS_ERR(server)) {
		error = PTR_ERR(server);
1919
		goto out;
D
David Howells 已提交
1920
	}
T
Trond Myklebust 已提交
1921
	sb_mntdata.server = server;
D
David Howells 已提交
1922

1923 1924 1925
	if (server->flags & NFS_MOUNT_UNSHARED)
		compare_super = NULL;

1926
	/* Get a superblock - note that we may end up sharing one that already exists */
T
Trond Myklebust 已提交
1927
	s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
1928 1929
	if (IS_ERR(s)) {
		error = PTR_ERR(s);
1930
		goto out_err_nosb;
1931 1932
	}

1933 1934 1935
	if (s->s_fs_info != server) {
		nfs_free_server(server);
		server = NULL;
1936 1937 1938 1939
	} else {
		error = nfs_bdi_register(server);
		if (error)
			goto error_splat_super;
1940
	}
D
David Howells 已提交
1941

1942 1943
	if (!s->s_root) {
		/* initial superblock/root creation */
1944
		nfs_fill_super(s, data);
1945
	}
D
David Howells 已提交
1946

1947
	mntroot = nfs_get_root(s, mntfh);
1948 1949 1950
	if (IS_ERR(mntroot)) {
		error = PTR_ERR(mntroot);
		goto error_splat_super;
D
David Howells 已提交
1951
	}
1952

1953
	error = security_sb_set_mnt_opts(s, &data->lsm_opts);
1954 1955 1956
	if (error)
		goto error_splat_root;

1957 1958 1959
	s->s_flags |= MS_ACTIVE;
	mnt->mnt_sb = s;
	mnt->mnt_root = mntroot;
1960 1961 1962
	error = 0;

out:
1963 1964 1965 1966 1967 1968
	kfree(data->nfs_server.hostname);
	kfree(data->mount_server.hostname);
	security_free_mnt_opts(&data->lsm_opts);
out_free_fh:
	kfree(mntfh);
	kfree(data);
1969
	return error;
1970

1971 1972
out_err_nosb:
	nfs_free_server(server);
1973
	goto out;
1974

1975 1976
error_splat_root:
	dput(mntroot);
1977 1978 1979
error_splat_super:
	up_write(&s->s_umount);
	deactivate_super(s);
1980
	goto out;
D
David Howells 已提交
1981 1982
}

1983 1984 1985
/*
 * Destroy an NFS2/3 superblock
 */
D
David Howells 已提交
1986 1987 1988 1989
static void nfs_kill_super(struct super_block *s)
{
	struct nfs_server *server = NFS_SB(s);

1990
	bdi_unregister(&server->backing_dev_info);
D
David Howells 已提交
1991
	kill_anon_super(s);
1992
	nfs_free_server(server);
D
David Howells 已提交
1993 1994
}

1995 1996 1997 1998 1999 2000
/*
 * 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)
D
David Howells 已提交
2001 2002
{
	struct nfs_clone_mount *data = raw_data;
2003 2004 2005
	struct super_block *s;
	struct nfs_server *server;
	struct dentry *mntroot;
2006
	int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
T
Trond Myklebust 已提交
2007 2008 2009
	struct nfs_sb_mountdata sb_mntdata = {
		.mntflags = flags,
	};
2010
	int error;
D
David Howells 已提交
2011

2012
	dprintk("--> nfs_xdev_get_sb()\n");
D
David Howells 已提交
2013

2014 2015 2016 2017 2018 2019
	/* 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;
	}
T
Trond Myklebust 已提交
2020
	sb_mntdata.server = server;
2021

2022 2023 2024
	if (server->flags & NFS_MOUNT_UNSHARED)
		compare_super = NULL;

2025
	/* Get a superblock - note that we may end up sharing one that already exists */
T
Trond Myklebust 已提交
2026
	s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2027 2028 2029 2030
	if (IS_ERR(s)) {
		error = PTR_ERR(s);
		goto out_err_nosb;
	}
2031

2032 2033 2034
	if (s->s_fs_info != server) {
		nfs_free_server(server);
		server = NULL;
2035 2036 2037 2038
	} else {
		error = nfs_bdi_register(server);
		if (error)
			goto error_splat_super;
D
David Howells 已提交
2039
	}
2040

2041 2042 2043 2044
	if (!s->s_root) {
		/* initial superblock/root creation */
		nfs_clone_super(s, data->sb);
	}
D
David Howells 已提交
2045

2046 2047 2048 2049
	mntroot = nfs_get_root(s, data->fh);
	if (IS_ERR(mntroot)) {
		error = PTR_ERR(mntroot);
		goto error_splat_super;
D
David Howells 已提交
2050
	}
2051
	if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2052 2053 2054 2055
		dput(mntroot);
		error = -ESTALE;
		goto error_splat_super;
	}
D
David Howells 已提交
2056

2057 2058 2059
	s->s_flags |= MS_ACTIVE;
	mnt->mnt_sb = s;
	mnt->mnt_root = mntroot;
D
David Howells 已提交
2060

2061 2062 2063
	/* clone any lsm security options from the parent to the new sb */
	security_sb_clone_mnt_opts(data->sb, s);

2064 2065
	dprintk("<-- nfs_xdev_get_sb() = 0\n");
	return 0;
2066

2067 2068 2069 2070 2071
out_err_nosb:
	nfs_free_server(server);
out_err_noserver:
	dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
	return error;
D
David Howells 已提交
2072

2073 2074 2075 2076 2077
error_splat_super:
	up_write(&s->s_umount);
	deactivate_super(s);
	dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
	return error;
D
David Howells 已提交
2078 2079
}

2080 2081
#ifdef CONFIG_NFS_V4

D
David Howells 已提交
2082
/*
2083
 * Finish setting up a cloned NFS4 superblock
D
David Howells 已提交
2084
 */
2085 2086
static void nfs4_clone_super(struct super_block *sb,
			    const struct super_block *old_sb)
D
David Howells 已提交
2087
{
2088 2089 2090
	sb->s_blocksize_bits = old_sb->s_blocksize_bits;
	sb->s_blocksize = old_sb->s_blocksize;
	sb->s_maxbytes = old_sb->s_maxbytes;
D
David Howells 已提交
2091
	sb->s_time_gran = 1;
2092 2093
	sb->s_op = old_sb->s_op;
 	nfs_initialise_sb(sb);
D
David Howells 已提交
2094 2095
}

2096 2097 2098 2099
/*
 * Set up an NFS4 superblock
 */
static void nfs4_fill_super(struct super_block *sb)
D
David Howells 已提交
2100
{
2101 2102 2103
	sb->s_time_gran = 1;
	sb->s_op = &nfs4_sops;
	nfs_initialise_sb(sb);
D
David Howells 已提交
2104 2105
}

2106 2107 2108
/*
 * Validate NFSv4 mount options
 */
2109 2110 2111
static int nfs4_validate_mount_data(void *options,
				    struct nfs_parsed_mount_data *args,
				    const char *dev_name)
2112
{
2113
	struct sockaddr_in *ap;
2114
	struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2115 2116 2117 2118 2119
	char *c;

	if (data == NULL)
		goto out_no_data;

2120 2121 2122 2123 2124 2125
	args->rsize		= NFS_MAX_FILE_IO_SIZE;
	args->wsize		= NFS_MAX_FILE_IO_SIZE;
	args->acregmin		= 3;
	args->acregmax		= 60;
	args->acdirmin		= 30;
	args->acdirmax		= 60;
2126
	args->nfs_server.port	= NFS_PORT; /* 2049 unless user set port= */
2127

2128 2129
	switch (data->version) {
	case 1:
2130 2131 2132 2133
		ap = (struct sockaddr_in *)&args->nfs_server.address;
		if (data->host_addrlen > sizeof(args->nfs_server.address))
			goto out_no_address;
		if (data->host_addrlen == 0)
2134
			goto out_no_address;
2135 2136
		args->nfs_server.addrlen = data->host_addrlen;
		if (copy_from_user(ap, data->host_addr, data->host_addrlen))
2137
			return -EFAULT;
2138 2139
		if (!nfs_verify_server_address((struct sockaddr *)
						&args->nfs_server.address))
2140 2141 2142 2143
			goto out_no_address;

		switch (data->auth_flavourlen) {
		case 0:
2144
			args->auth_flavors[0] = RPC_AUTH_UNIX;
2145 2146
			break;
		case 1:
2147
			if (copy_from_user(&args->auth_flavors[0],
2148
					   data->auth_flavours,
2149
					   sizeof(args->auth_flavors[0])))
2150 2151 2152 2153 2154 2155 2156 2157 2158
				return -EFAULT;
			break;
		default:
			goto out_inval_auth;
		}

		c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
		if (IS_ERR(c))
			return PTR_ERR(c);
2159
		args->nfs_server.hostname = c;
2160 2161 2162 2163

		c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
		if (IS_ERR(c))
			return PTR_ERR(c);
2164 2165
		args->nfs_server.export_path = c;
		dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2166 2167 2168 2169

		c = strndup_user(data->client_addr.data, 16);
		if (IS_ERR(c))
			return PTR_ERR(c);
2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186
		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;
2187
		nfs_validate_transport_protocol(args);
2188 2189

		break;
2190
	default: {
2191
		int status;
2192 2193

		if (nfs_parse_mount_options((char *)options, args) == 0)
2194 2195 2196
			return -EINVAL;

		if (!nfs_verify_server_address((struct sockaddr *)
2197
						&args->nfs_server.address))
2198 2199
			return -EINVAL;

2200 2201
		nfs_validate_transport_protocol(args);

2202
		switch (args->auth_flavor_len) {
2203
		case 0:
2204
			args->auth_flavors[0] = RPC_AUTH_UNIX;
2205 2206 2207 2208 2209 2210 2211
			break;
		case 1:
			break;
		default:
			goto out_inval_auth;
		}

2212
		if (args->client_address == NULL)
2213 2214
			goto out_no_client_address;

2215 2216 2217 2218 2219 2220 2221 2222
		status = nfs_parse_devname(dev_name,
					   &args->nfs_server.hostname,
					   NFS4_MAXNAMLEN,
					   &args->nfs_server.export_path,
					   NFS4_MAXPATHLEN);
		if (status < 0)
			return status;

2223 2224
		break;
		}
2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240
	}

	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;
2241 2242 2243 2244

out_no_client_address:
	dfprintk(MOUNT, "NFS4: mount program didn't pass callback address\n");
	return -EINVAL;
2245 2246
}

2247 2248 2249
/*
 * Get the superblock for an NFS4 mountpoint
 */
2250 2251
static int nfs4_get_sb(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
D
David Howells 已提交
2252
{
2253
	struct nfs_parsed_mount_data *data;
2254 2255
	struct super_block *s;
	struct nfs_server *server;
2256
	struct nfs_fh *mntfh;
2257
	struct dentry *mntroot;
2258
	int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
T
Trond Myklebust 已提交
2259 2260 2261
	struct nfs_sb_mountdata sb_mntdata = {
		.mntflags = flags,
	};
2262 2263 2264 2265 2266 2267
	int error = -ENOMEM;

	data = kzalloc(sizeof(*data), GFP_KERNEL);
	mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
	if (data == NULL || mntfh == NULL)
		goto out_free_fh;
D
David Howells 已提交
2268

2269
	security_init_mnt_opts(&data->lsm_opts);
2270

2271
	/* Validate the mount data */
2272
	error = nfs4_validate_mount_data(raw_data, data, dev_name);
2273 2274
	if (error < 0)
		goto out;
D
David Howells 已提交
2275

2276
	/* Get a volume representation */
2277
	server = nfs4_create_server(data, mntfh);
2278 2279
	if (IS_ERR(server)) {
		error = PTR_ERR(server);
2280
		goto out;
D
David Howells 已提交
2281
	}
T
Trond Myklebust 已提交
2282
	sb_mntdata.server = server;
D
David Howells 已提交
2283

2284 2285 2286
	if (server->flags & NFS4_MOUNT_UNSHARED)
		compare_super = NULL;

2287
	/* Get a superblock - note that we may end up sharing one that already exists */
T
Trond Myklebust 已提交
2288
	s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2289 2290
	if (IS_ERR(s)) {
		error = PTR_ERR(s);
D
David Howells 已提交
2291
		goto out_free;
2292 2293
	}

2294 2295 2296
	if (s->s_fs_info != server) {
		nfs_free_server(server);
		server = NULL;
2297 2298 2299 2300
	} else {
		error = nfs_bdi_register(server);
		if (error)
			goto error_splat_super;
2301 2302
	}

2303 2304 2305 2306
	if (!s->s_root) {
		/* initial superblock/root creation */
		nfs4_fill_super(s);
	}
D
David Howells 已提交
2307

2308
	mntroot = nfs4_get_root(s, mntfh);
2309 2310 2311
	if (IS_ERR(mntroot)) {
		error = PTR_ERR(mntroot);
		goto error_splat_super;
D
David Howells 已提交
2312
	}
2313

2314
	error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2315 2316 2317
	if (error)
		goto error_splat_root;

D
David Howells 已提交
2318
	s->s_flags |= MS_ACTIVE;
2319 2320
	mnt->mnt_sb = s;
	mnt->mnt_root = mntroot;
2321 2322 2323
	error = 0;

out:
2324 2325 2326 2327 2328 2329 2330
	kfree(data->client_address);
	kfree(data->nfs_server.export_path);
	kfree(data->nfs_server.hostname);
	security_free_mnt_opts(&data->lsm_opts);
out_free_fh:
	kfree(mntfh);
	kfree(data);
2331
	return error;
2332

D
David Howells 已提交
2333
out_free:
2334
	nfs_free_server(server);
2335
	goto out;
2336

2337 2338
error_splat_root:
	dput(mntroot);
2339 2340 2341
error_splat_super:
	up_write(&s->s_umount);
	deactivate_super(s);
2342
	goto out;
D
David Howells 已提交
2343 2344 2345 2346 2347 2348 2349 2350 2351 2352
}

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);
2353
	nfs_free_server(server);
D
David Howells 已提交
2354 2355 2356
}

/*
2357
 * Clone an NFS4 server record on xdev traversal (FSID-change)
D
David Howells 已提交
2358
 */
2359 2360 2361
static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
			    const char *dev_name, void *raw_data,
			    struct vfsmount *mnt)
D
David Howells 已提交
2362
{
2363 2364 2365 2366
	struct nfs_clone_mount *data = raw_data;
	struct super_block *s;
	struct nfs_server *server;
	struct dentry *mntroot;
2367
	int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
T
Trond Myklebust 已提交
2368 2369 2370
	struct nfs_sb_mountdata sb_mntdata = {
		.mntflags = flags,
	};
2371
	int error;
D
David Howells 已提交
2372

2373
	dprintk("--> nfs4_xdev_get_sb()\n");
D
David Howells 已提交
2374

2375 2376 2377 2378 2379
	/* 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;
D
David Howells 已提交
2380
	}
T
Trond Myklebust 已提交
2381
	sb_mntdata.server = server;
D
David Howells 已提交
2382

2383 2384 2385
	if (server->flags & NFS4_MOUNT_UNSHARED)
		compare_super = NULL;

2386
	/* Get a superblock - note that we may end up sharing one that already exists */
T
Trond Myklebust 已提交
2387
	s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2388 2389 2390
	if (IS_ERR(s)) {
		error = PTR_ERR(s);
		goto out_err_nosb;
D
David Howells 已提交
2391 2392
	}

2393 2394 2395
	if (s->s_fs_info != server) {
		nfs_free_server(server);
		server = NULL;
2396 2397 2398 2399
	} else {
		error = nfs_bdi_register(server);
		if (error)
			goto error_splat_super;
2400
	}
D
David Howells 已提交
2401

2402 2403 2404 2405
	if (!s->s_root) {
		/* initial superblock/root creation */
		nfs4_clone_super(s, data->sb);
	}
D
David Howells 已提交
2406

2407 2408 2409 2410 2411
	mntroot = nfs4_get_root(s, data->fh);
	if (IS_ERR(mntroot)) {
		error = PTR_ERR(mntroot);
		goto error_splat_super;
	}
2412 2413 2414 2415 2416
	if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
		dput(mntroot);
		error = -ESTALE;
		goto error_splat_super;
	}
D
David Howells 已提交
2417

2418 2419 2420 2421
	s->s_flags |= MS_ACTIVE;
	mnt->mnt_sb = s;
	mnt->mnt_root = mntroot;

2422 2423
	security_sb_clone_mnt_opts(data->sb, s);

2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437
	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;
D
David Howells 已提交
2438 2439
}

2440 2441 2442 2443 2444 2445
/*
 * 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)
D
David Howells 已提交
2446 2447
{
	struct nfs_clone_mount *data = raw_data;
2448 2449 2450 2451
	struct super_block *s;
	struct nfs_server *server;
	struct dentry *mntroot;
	struct nfs_fh mntfh;
2452
	int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
T
Trond Myklebust 已提交
2453 2454 2455
	struct nfs_sb_mountdata sb_mntdata = {
		.mntflags = flags,
	};
2456 2457 2458 2459 2460 2461 2462 2463 2464 2465
	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;
	}
T
Trond Myklebust 已提交
2466
	sb_mntdata.server = server;
2467

2468 2469 2470
	if (server->flags & NFS4_MOUNT_UNSHARED)
		compare_super = NULL;

2471
	/* Get a superblock - note that we may end up sharing one that already exists */
T
Trond Myklebust 已提交
2472
	s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2473 2474 2475 2476 2477 2478 2479 2480
	if (IS_ERR(s)) {
		error = PTR_ERR(s);
		goto out_err_nosb;
	}

	if (s->s_fs_info != server) {
		nfs_free_server(server);
		server = NULL;
2481 2482 2483 2484
	} else {
		error = nfs_bdi_register(server);
		if (error)
			goto error_splat_super;
2485 2486 2487 2488 2489 2490 2491
	}

	if (!s->s_root) {
		/* initial superblock/root creation */
		nfs4_fill_super(s);
	}

2492
	mntroot = nfs4_get_root(s, &mntfh);
2493 2494 2495 2496
	if (IS_ERR(mntroot)) {
		error = PTR_ERR(mntroot);
		goto error_splat_super;
	}
2497 2498 2499 2500 2501
	if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
		dput(mntroot);
		error = -ESTALE;
		goto error_splat_super;
	}
2502 2503 2504 2505 2506

	s->s_flags |= MS_ACTIVE;
	mnt->mnt_sb = s;
	mnt->mnt_root = mntroot;

2507 2508
	security_sb_clone_mnt_opts(data->sb, s);

2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522
	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;
D
David Howells 已提交
2523 2524
}

2525
#endif /* CONFIG_NFS_V4 */