Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1200 insertions, 0 deletions

diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
new file mode 100644
index 00000000000..9a11aa39e2e
--- /dev/null
+++ b/fs/nfsd/export.c
@@ -0,0 +1,1200 @@
+#define MSNFS	/* HACK HACK */
+/*
+ * linux/fs/nfsd/export.c
+ *
+ * NFS exporting and validation.
+ *
+ * We maintain a list of clients, each of which has a list of
+ * exports. To export an fs to a given client, you first have
+ * to create the client entry with NFSCTL_ADDCLIENT, which
+ * creates a client control block and adds it to the hash
+ * table. Then, you call NFSCTL_EXPORT for each fs.
+ *
+ *
+ * Copyright (C) 1995, 1996 Olaf Kirch, <okir@monad.swb.de>
+ */
+
+#include <linux/unistd.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/stat.h>
+#include <linux/in.h>
+#include <linux/seq_file.h>
+#include <linux/syscalls.h>
+#include <linux/rwsem.h>
+#include <linux/dcache.h>
+#include <linux/namei.h>
+#include <linux/mount.h>
+#include <linux/hash.h>
+
+#include <linux/sunrpc/svc.h>
+#include <linux/nfsd/nfsd.h>
+#include <linux/nfsd/nfsfh.h>
+#include <linux/nfsd/syscall.h>
+#include <linux/lockd/bind.h>
+
+#define NFSDDBG_FACILITY	NFSDDBG_EXPORT
+#define NFSD_PARANOIA 1
+
+typedef struct auth_domain	svc_client;
+typedef struct svc_export	svc_export;
+
+static void		exp_do_unexport(svc_export *unexp);
+static int		exp_verify_string(char *cp, int max);
+
+/*
+ * We have two caches.
+ * One maps client+vfsmnt+dentry to export options - the export map
+ * The other maps client+filehandle-fragment to export options. - the expkey map
+ *
+ * The export options are actually stored in the first map, and the
+ * second map contains a reference to the entry in the first map.
+ */
+
+#define	EXPKEY_HASHBITS		8
+#define	EXPKEY_HASHMAX		(1 << EXPKEY_HASHBITS)
+#define	EXPKEY_HASHMASK		(EXPKEY_HASHMAX -1)
+static struct cache_head *expkey_table[EXPKEY_HASHMAX];
+
+static inline int svc_expkey_hash(struct svc_expkey *item)
+{
+	int hash = item->ek_fsidtype;
+	char * cp = (char*)item->ek_fsid;
+	int len = key_len(item->ek_fsidtype);
+
+	hash ^= hash_mem(cp, len, EXPKEY_HASHBITS);
+	hash ^= hash_ptr(item->ek_client, EXPKEY_HASHBITS);
+	return hash & EXPKEY_HASHMASK;
+}
+
+void expkey_put(struct cache_head *item, struct cache_detail *cd)
+{
+	if (cache_put(item, cd)) {
+		struct svc_expkey *key = container_of(item, struct svc_expkey, h);
+		if (test_bit(CACHE_VALID, &item->flags) &&
+		    !test_bit(CACHE_NEGATIVE, &item->flags))
+			exp_put(key->ek_export);
+		auth_domain_put(key->ek_client);
+		kfree(key);
+	}
+}
+
+static void expkey_request(struct cache_detail *cd,
+			   struct cache_head *h,
+			   char **bpp, int *blen)
+{
+	/* client fsidtype \xfsid */
+	struct svc_expkey *ek = container_of(h, struct svc_expkey, h);
+	char type[5];
+
+	qword_add(bpp, blen, ek->ek_client->name);
+	snprintf(type, 5, "%d", ek->ek_fsidtype);
+	qword_add(bpp, blen, type);
+	qword_addhex(bpp, blen, (char*)ek->ek_fsid, key_len(ek->ek_fsidtype));
+	(*bpp)[-1] = '\n';
+}
+
+static struct svc_expkey *svc_expkey_lookup(struct svc_expkey *, int);
+static int expkey_parse(struct cache_detail *cd, char *mesg, int mlen)
+{
+	/* client fsidtype fsid [path] */
+	char *buf;
+	int len;
+	struct auth_domain *dom = NULL;
+	int err;
+	int fsidtype;
+	char *ep;
+	struct svc_expkey key;
+
+	if (mesg[mlen-1] != '\n')
+		return -EINVAL;
+	mesg[mlen-1] = 0;
+
+	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	err = -ENOMEM;
+	if (!buf) goto out;
+
+	err = -EINVAL;
+	if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
+		goto out;
+
+	err = -ENOENT;
+	dom = auth_domain_find(buf);
+	if (!dom)
+		goto out;
+	dprintk("found domain %s\n", buf);
+
+	err = -EINVAL;
+	if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
+		goto out;
+	fsidtype = simple_strtoul(buf, &ep, 10);
+	if (*ep)
+		goto out;
+	dprintk("found fsidtype %d\n", fsidtype);
+	if (fsidtype > 2)
+		goto out;
+	if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
+		goto out;
+	dprintk("found fsid length %d\n", len);
+	if (len != key_len(fsidtype))
+		goto out;
+
+	/* OK, we seem to have a valid key */
+	key.h.flags = 0;
+	key.h.expiry_time = get_expiry(&mesg);
+	if (key.h.expiry_time == 0)
+		goto out;
+
+	key.ek_client = dom;	
+	key.ek_fsidtype = fsidtype;
+	memcpy(key.ek_fsid, buf, len);
+
+	/* now we want a pathname, or empty meaning NEGATIVE  */
+	if ((len=qword_get(&mesg, buf, PAGE_SIZE)) < 0)
+		goto out;
+	dprintk("Path seems to be <%s>\n", buf);
+	err = 0;
+	if (len == 0) {
+		struct svc_expkey *ek;
+		set_bit(CACHE_NEGATIVE, &key.h.flags);
+		ek = svc_expkey_lookup(&key, 1);
+		if (ek)
+			expkey_put(&ek->h, &svc_expkey_cache);
+	} else {
+		struct nameidata nd;
+		struct svc_expkey *ek;
+		struct svc_export *exp;
+		err = path_lookup(buf, 0, &nd);
+		if (err)
+			goto out;
+
+		dprintk("Found the path %s\n", buf);
+		exp = exp_get_by_name(dom, nd.mnt, nd.dentry, NULL);
+
+		err = -ENOENT;
+		if (!exp)
+			goto out_nd;
+		key.ek_export = exp;
+		dprintk("And found export\n");
+		
+		ek = svc_expkey_lookup(&key, 1);
+		if (ek)
+			expkey_put(&ek->h, &svc_expkey_cache);
+		exp_put(exp);
+		err = 0;
+	out_nd:
+		path_release(&nd);
+	}
+	cache_flush();
+ out:
+	if (dom)
+		auth_domain_put(dom);
+	if (buf)
+		kfree(buf);
+	return err;
+}
+
+static int expkey_show(struct seq_file *m,
+		       struct cache_detail *cd,
+		       struct cache_head *h)
+{
+	struct svc_expkey *ek ;
+
+	if (h ==NULL) {
+		seq_puts(m, "#domain fsidtype fsid [path]\n");
+		return 0;
+	}
+	ek = container_of(h, struct svc_expkey, h);
+	seq_printf(m, "%s %d 0x%08x", ek->ek_client->name,
+		   ek->ek_fsidtype, ek->ek_fsid[0]);
+	if (ek->ek_fsidtype != 1)
+		seq_printf(m, "%08x", ek->ek_fsid[1]);
+	if (ek->ek_fsidtype == 2)
+		seq_printf(m, "%08x", ek->ek_fsid[2]);
+	if (test_bit(CACHE_VALID, &h->flags) && 
+	    !test_bit(CACHE_NEGATIVE, &h->flags)) {
+		seq_printf(m, " ");
+		seq_path(m, ek->ek_export->ex_mnt, ek->ek_export->ex_dentry, "\\ \t\n");
+	}
+	seq_printf(m, "\n");
+	return 0;
+}
+	
+struct cache_detail svc_expkey_cache = {
+	.hash_size	= EXPKEY_HASHMAX,
+	.hash_table	= expkey_table,
+	.name		= "nfsd.fh",
+	.cache_put	= expkey_put,
+	.cache_request	= expkey_request,
+	.cache_parse	= expkey_parse,
+	.cache_show	= expkey_show,
+};
+
+static inline int svc_expkey_match (struct svc_expkey *a, struct svc_expkey *b)
+{
+	if (a->ek_fsidtype != b->ek_fsidtype ||
+	    a->ek_client != b->ek_client ||
+	    memcmp(a->ek_fsid, b->ek_fsid, key_len(a->ek_fsidtype)) != 0)
+		return 0;
+	return 1;
+}
+
+static inline void svc_expkey_init(struct svc_expkey *new, struct svc_expkey *item)
+{
+	cache_get(&item->ek_client->h);
+	new->ek_client = item->ek_client;
+	new->ek_fsidtype = item->ek_fsidtype;
+	new->ek_fsid[0] = item->ek_fsid[0];
+	new->ek_fsid[1] = item->ek_fsid[1];
+	new->ek_fsid[2] = item->ek_fsid[2];
+}
+
+static inline void svc_expkey_update(struct svc_expkey *new, struct svc_expkey *item)
+{
+	cache_get(&item->ek_export->h);
+	new->ek_export = item->ek_export;
+}
+
+static DefineSimpleCacheLookup(svc_expkey,0) /* no inplace updates */
+
+#define	EXPORT_HASHBITS		8
+#define	EXPORT_HASHMAX		(1<< EXPORT_HASHBITS)
+#define	EXPORT_HASHMASK		(EXPORT_HASHMAX -1)
+
+static struct cache_head *export_table[EXPORT_HASHMAX];
+
+static inline int svc_export_hash(struct svc_export *item)
+{
+	int rv;
+
+	rv = hash_ptr(item->ex_client, EXPORT_HASHBITS);
+	rv ^= hash_ptr(item->ex_dentry, EXPORT_HASHBITS);
+	rv ^= hash_ptr(item->ex_mnt, EXPORT_HASHBITS);
+	return rv;
+}
+
+void svc_export_put(struct cache_head *item, struct cache_detail *cd)
+{
+	if (cache_put(item, cd)) {
+		struct svc_export *exp = container_of(item, struct svc_export, h);
+		dput(exp->ex_dentry);
+		mntput(exp->ex_mnt);
+		auth_domain_put(exp->ex_client);
+		kfree(exp);
+	}
+}
+
+static void svc_export_request(struct cache_detail *cd,
+			       struct cache_head *h,
+			       char **bpp, int *blen)
+{
+	/*  client path */
+	struct svc_export *exp = container_of(h, struct svc_export, h);
+	char *pth;
+
+	qword_add(bpp, blen, exp->ex_client->name);
+	pth = d_path(exp->ex_dentry, exp->ex_mnt, *bpp, *blen);
+	if (IS_ERR(pth)) {
+		/* is this correct? */
+		(*bpp)[0] = '\n';
+		return;
+	}
+	qword_add(bpp, blen, pth);
+	(*bpp)[-1] = '\n';
+}
+
+static struct svc_export *svc_export_lookup(struct svc_export *, int);
+
+static int check_export(struct inode *inode, int flags)
+{
+
+	/* We currently export only dirs and regular files.
+	 * This is what umountd does.
+	 */
+	if (!S_ISDIR(inode->i_mode) &&
+	    !S_ISREG(inode->i_mode))
+		return -ENOTDIR;
+
+	/* There are two requirements on a filesystem to be exportable.
+	 * 1:  We must be able to identify the filesystem from a number.
+	 *       either a device number (so FS_REQUIRES_DEV needed)
+	 *       or an FSID number (so NFSEXP_FSID needed).
+	 * 2:  We must be able to find an inode from a filehandle.
+	 *       This means that s_export_op must be set.
+	 */
+	if (!(inode->i_sb->s_type->fs_flags & FS_REQUIRES_DEV) &&
+	    !(flags & NFSEXP_FSID)) {
+		dprintk("exp_export: export of non-dev fs without fsid");
+		return -EINVAL;
+	}
+	if (!inode->i_sb->s_export_op) {
+		dprintk("exp_export: export of invalid fs type.\n");
+		return -EINVAL;
+	}
+
+	/* Ok, we can export it */;
+	if (!inode->i_sb->s_export_op->find_exported_dentry)
+		inode->i_sb->s_export_op->find_exported_dentry =
+			find_exported_dentry;
+	return 0;
+
+}
+
+static int svc_export_parse(struct cache_detail *cd, char *mesg, int mlen)
+{
+	/* client path expiry [flags anonuid anongid fsid] */
+	char *buf;
+	int len;
+	int err;
+	struct auth_domain *dom = NULL;
+	struct nameidata nd;
+	struct svc_export exp, *expp;
+	int an_int;
+
+	nd.dentry = NULL;
+
+	if (mesg[mlen-1] != '\n')
+		return -EINVAL;
+	mesg[mlen-1] = 0;
+
+	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	err = -ENOMEM;
+	if (!buf) goto out;
+
+	/* client */
+	len = qword_get(&mesg, buf, PAGE_SIZE);
+	err = -EINVAL;
+	if (len <= 0) goto out;
+
+	err = -ENOENT;
+	dom = auth_domain_find(buf);
+	if (!dom)
+		goto out;
+
+	/* path */
+	err = -EINVAL;
+	if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
+		goto out;
+	err = path_lookup(buf, 0, &nd);
+	if (err) goto out;
+
+	exp.h.flags = 0;
+	exp.ex_client = dom;
+	exp.ex_mnt = nd.mnt;
+	exp.ex_dentry = nd.dentry;
+
+	/* expiry */
+	err = -EINVAL;
+	exp.h.expiry_time = get_expiry(&mesg);
+	if (exp.h.expiry_time == 0)
+		goto out;
+
+	/* flags */
+	err = get_int(&mesg, &an_int);
+	if (err == -ENOENT)
+		set_bit(CACHE_NEGATIVE, &exp.h.flags);
+	else {
+		if (err || an_int < 0) goto out;	
+		exp.ex_flags= an_int;
+	
+		/* anon uid */
+		err = get_int(&mesg, &an_int);
+		if (err) goto out;
+		exp.ex_anon_uid= an_int;
+
+		/* anon gid */
+		err = get_int(&mesg, &an_int);
+		if (err) goto out;
+		exp.ex_anon_gid= an_int;
+
+		/* fsid */
+		err = get_int(&mesg, &an_int);
+		if (err) goto out;
+		exp.ex_fsid = an_int;
+
+		err = check_export(nd.dentry->d_inode, exp.ex_flags);
+		if (err) goto out;
+	}
+
+	expp = svc_export_lookup(&exp, 1);
+	if (expp)
+		exp_put(expp);
+	err = 0;
+	cache_flush();
+ out:
+	if (nd.dentry)
+		path_release(&nd);
+	if (dom)
+		auth_domain_put(dom);
+	if (buf)
+		kfree(buf);
+	return err;
+}
+
+static void exp_flags(struct seq_file *m, int flag, int fsid, uid_t anonu, uid_t anong);
+
+static int svc_export_show(struct seq_file *m,
+			   struct cache_detail *cd,
+			   struct cache_head *h)
+{
+	struct svc_export *exp ;
+
+	if (h ==NULL) {
+		seq_puts(m, "#path domain(flags)\n");
+		return 0;
+	}
+	exp = container_of(h, struct svc_export, h);
+	seq_path(m, exp->ex_mnt, exp->ex_dentry, " \t\n\\");
+	seq_putc(m, '\t');
+	seq_escape(m, exp->ex_client->name, " \t\n\\");
+	seq_putc(m, '(');
+	if (test_bit(CACHE_VALID, &h->flags) && 
+	    !test_bit(CACHE_NEGATIVE, &h->flags))
+		exp_flags(m, exp->ex_flags, exp->ex_fsid, 
+			  exp->ex_anon_uid, exp->ex_anon_gid);
+	seq_puts(m, ")\n");
+	return 0;
+}
+struct cache_detail svc_export_cache = {
+	.hash_size	= EXPORT_HASHMAX,
+	.hash_table	= export_table,
+	.name		= "nfsd.export",
+	.cache_put	= svc_export_put,
+	.cache_request	= svc_export_request,
+	.cache_parse	= svc_export_parse,
+	.cache_show	= svc_export_show,
+};
+
+static inline int svc_export_match(struct svc_export *a, struct svc_export *b)
+{
+	return a->ex_client == b->ex_client &&
+		a->ex_dentry == b->ex_dentry &&
+		a->ex_mnt == b->ex_mnt;
+}
+static inline void svc_export_init(struct svc_export *new, struct svc_export *item)
+{
+	cache_get(&item->ex_client->h);
+	new->ex_client = item->ex_client;
+	new->ex_dentry = dget(item->ex_dentry);
+	new->ex_mnt = mntget(item->ex_mnt);
+}
+
+static inline void svc_export_update(struct svc_export *new, struct svc_export *item)
+{
+	new->ex_flags = item->ex_flags;
+	new->ex_anon_uid = item->ex_anon_uid;
+	new->ex_anon_gid = item->ex_anon_gid;
+	new->ex_fsid = item->ex_fsid;
+}
+
+static DefineSimpleCacheLookup(svc_export,1) /* allow inplace updates */
+
+
+struct svc_expkey *
+exp_find_key(svc_client *clp, int fsid_type, u32 *fsidv, struct cache_req *reqp)
+{
+	struct svc_expkey key, *ek;
+	int err;
+	
+	if (!clp)
+		return NULL;
+
+	key.ek_client = clp;
+	key.ek_fsidtype = fsid_type;
+	memcpy(key.ek_fsid, fsidv, key_len(fsid_type));
+
+	ek = svc_expkey_lookup(&key, 0);
+	if (ek != NULL)
+		if ((err = cache_check(&svc_expkey_cache, &ek->h, reqp)))
+			ek = ERR_PTR(err);
+	return ek;
+}
+
+static int exp_set_key(svc_client *clp, int fsid_type, u32 *fsidv,
+		       struct svc_export *exp)
+{
+	struct svc_expkey key, *ek;
+
+	key.ek_client = clp;
+	key.ek_fsidtype = fsid_type;
+	memcpy(key.ek_fsid, fsidv, key_len(fsid_type));
+	key.ek_export = exp;
+	key.h.expiry_time = NEVER;
+	key.h.flags = 0;
+
+	ek = svc_expkey_lookup(&key, 1);
+	if (ek) {
+		expkey_put(&ek->h, &svc_expkey_cache);
+		return 0;
+	}
+	return -ENOMEM;
+}
+
+/*
+ * Find the client's export entry matching xdev/xino.
+ */
+static inline struct svc_expkey *
+exp_get_key(svc_client *clp, dev_t dev, ino_t ino)
+{
+	u32 fsidv[3];
+	
+	if (old_valid_dev(dev)) {
+		mk_fsid_v0(fsidv, dev, ino);
+		return exp_find_key(clp, 0, fsidv, NULL);
+	}
+	mk_fsid_v3(fsidv, dev, ino);
+	return exp_find_key(clp, 3, fsidv, NULL);
+}
+
+/*
+ * Find the client's export entry matching fsid
+ */
+static inline struct svc_expkey *
+exp_get_fsid_key(svc_client *clp, int fsid)
+{
+	u32 fsidv[2];
+
+	mk_fsid_v1(fsidv, fsid);
+
+	return exp_find_key(clp, 1, fsidv, NULL);
+}
+
+svc_export *
+exp_get_by_name(svc_client *clp, struct vfsmount *mnt, struct dentry *dentry,
+		struct cache_req *reqp)
+{
+	struct svc_export *exp, key;
+	
+	if (!clp)
+		return NULL;
+
+	key.ex_client = clp;
+	key.ex_mnt = mnt;
+	key.ex_dentry = dentry;
+
+	exp = svc_export_lookup(&key, 0);
+	if (exp != NULL) 
+		switch (cache_check(&svc_export_cache, &exp->h, reqp)) {
+		case 0: break;
+		case -EAGAIN:
+			exp = ERR_PTR(-EAGAIN);
+			break;
+		default:
+			exp = NULL;
+		}
+
+	return exp;
+}
+
+/*
+ * Find the export entry for a given dentry.
+ */
+struct svc_export *
+exp_parent(svc_client *clp, struct vfsmount *mnt, struct dentry *dentry,
+	   struct cache_req *reqp)
+{
+	svc_export *exp;
+
+	dget(dentry);
+	exp = exp_get_by_name(clp, mnt, dentry, reqp);
+
+	while (exp == NULL && !IS_ROOT(dentry)) {
+		struct dentry *parent;
+
+		parent = dget_parent(dentry);
+		dput(dentry);
+		dentry = parent;
+		exp = exp_get_by_name(clp, mnt, dentry, reqp);
+	}
+	dput(dentry);
+	return exp;
+}
+
+/*
+ * Hashtable locking. Write locks are placed only by user processes
+ * wanting to modify export information.
+ * Write locking only done in this file.  Read locking
+ * needed externally.
+ */
+
+static DECLARE_RWSEM(hash_sem);
+
+void
+exp_readlock(void)
+{
+	down_read(&hash_sem);
+}
+
+static inline void
+exp_writelock(void)
+{
+	down_write(&hash_sem);
+}
+
+void
+exp_readunlock(void)
+{
+	up_read(&hash_sem);
+}
+
+static inline void
+exp_writeunlock(void)
+{
+	up_write(&hash_sem);
+}
+
+static void exp_fsid_unhash(struct svc_export *exp)
+{
+	struct svc_expkey *ek;
+
+	if ((exp->ex_flags & NFSEXP_FSID) == 0)
+		return;
+
+	ek = exp_get_fsid_key(exp->ex_client, exp->ex_fsid);
+	if (ek && !IS_ERR(ek)) {
+		ek->h.expiry_time = get_seconds()-1;
+		expkey_put(&ek->h, &svc_expkey_cache);
+	}
+	svc_expkey_cache.nextcheck = get_seconds();
+}
+
+static int exp_fsid_hash(svc_client *clp, struct svc_export *exp)
+{
+	u32 fsid[2];
+ 
+	if ((exp->ex_flags & NFSEXP_FSID) == 0)
+		return 0;
+
+	mk_fsid_v1(fsid, exp->ex_fsid);
+	return exp_set_key(clp, 1, fsid, exp);
+}
+
+static int exp_hash(struct auth_domain *clp, struct svc_export *exp)
+{
+	u32 fsid[2];
+	struct inode *inode = exp->ex_dentry->d_inode;
+	dev_t dev = inode->i_sb->s_dev;
+
+	if (old_valid_dev(dev)) {
+		mk_fsid_v0(fsid, dev, inode->i_ino);
+		return exp_set_key(clp, 0, fsid, exp);
+	}
+	mk_fsid_v3(fsid, dev, inode->i_ino);
+	return exp_set_key(clp, 3, fsid, exp);
+}
+
+static void exp_unhash(struct svc_export *exp)
+{
+	struct svc_expkey *ek;
+	struct inode *inode = exp->ex_dentry->d_inode;
+
+	ek = exp_get_key(exp->ex_client, inode->i_sb->s_dev, inode->i_ino);
+	if (ek && !IS_ERR(ek)) {
+		ek->h.expiry_time = get_seconds()-1;
+		expkey_put(&ek->h, &svc_expkey_cache);
+	}
+	svc_expkey_cache.nextcheck = get_seconds();
+}
+	
+/*
+ * Export a file system.
+ */
+int
+exp_export(struct nfsctl_export *nxp)
+{
+	svc_client	*clp;
+	struct svc_export	*exp = NULL;
+	struct svc_export	new;
+	struct svc_expkey	*fsid_key = NULL;
+	struct nameidata nd;
+	int		err;
+
+	/* Consistency check */
+	err = -EINVAL;
+	if (!exp_verify_string(nxp->ex_path, NFS_MAXPATHLEN) ||
+	    !exp_verify_string(nxp->ex_client, NFSCLNT_IDMAX))
+		goto out;
+
+	dprintk("exp_export called for %s:%s (%x/%ld fl %x).\n",
+			nxp->ex_client, nxp->ex_path,
+			(unsigned)nxp->ex_dev, (long)nxp->ex_ino,
+			nxp->ex_flags);
+
+	/* Try to lock the export table for update */
+	exp_writelock();
+
+	/* Look up client info */
+	if (!(clp = auth_domain_find(nxp->ex_client)))
+		goto out_unlock;
+
+
+	/* Look up the dentry */
+	err = path_lookup(nxp->ex_path, 0, &nd);
+	if (err)
+		goto out_unlock;
+	err = -EINVAL;
+
+	exp = exp_get_by_name(clp, nd.mnt, nd.dentry, NULL);
+
+	/* must make sure there won't be an ex_fsid clash */
+	if ((nxp->ex_flags & NFSEXP_FSID) &&
+	    (fsid_key = exp_get_fsid_key(clp, nxp->ex_dev)) &&
+	    !IS_ERR(fsid_key) &&
+	    fsid_key->ek_export &&
+	    fsid_key->ek_export != exp)
+		goto finish;
+
+	if (exp) {
+		/* just a flags/id/fsid update */
+
+		exp_fsid_unhash(exp);
+		exp->ex_flags    = nxp->ex_flags;
+		exp->ex_anon_uid = nxp->ex_anon_uid;
+		exp->ex_anon_gid = nxp->ex_anon_gid;
+		exp->ex_fsid     = nxp->ex_dev;
+
+		err = exp_fsid_hash(clp, exp);
+		goto finish;
+	}
+
+	err = check_export(nd.dentry->d_inode, nxp->ex_flags);
+	if (err) goto finish;
+
+	err = -ENOMEM;
+
+	dprintk("nfsd: creating export entry %p for client %p\n", exp, clp);
+
+	new.h.expiry_time = NEVER;
+	new.h.flags = 0;
+	new.ex_client = clp;
+	new.ex_mnt = nd.mnt;
+	new.ex_dentry = nd.dentry;
+	new.ex_flags = nxp->ex_flags;
+	new.ex_anon_uid = nxp->ex_anon_uid;
+	new.ex_anon_gid = nxp->ex_anon_gid;
+	new.ex_fsid = nxp->ex_dev;
+
+	exp = svc_export_lookup(&new, 1);
+
+	if (exp == NULL)
+		goto finish;
+
+	err = 0;
+
+	if (exp_hash(clp, exp) ||
+	    exp_fsid_hash(clp, exp)) {
+		/* failed to create at least one index */
+		exp_do_unexport(exp);
+		cache_flush();
+		err = -ENOMEM;
+	}
+
+finish:
+	if (exp)
+		exp_put(exp);
+	if (fsid_key && !IS_ERR(fsid_key))
+		expkey_put(&fsid_key->h, &svc_expkey_cache);
+	if (clp)
+		auth_domain_put(clp);
+	path_release(&nd);
+out_unlock:
+	exp_writeunlock();
+out:
+	return err;
+}
+
+/*
+ * Unexport a file system. The export entry has already
+ * been removed from the client's list of exported fs's.
+ */
+static void
+exp_do_unexport(svc_export *unexp)
+{
+	unexp->h.expiry_time = get_seconds()-1;
+	svc_export_cache.nextcheck = get_seconds();
+	exp_unhash(unexp);
+	exp_fsid_unhash(unexp);
+}
+
+
+/*
+ * unexport syscall.
+ */
+int
+exp_unexport(struct nfsctl_export *nxp)
+{
+	struct auth_domain *dom;
+	svc_export *exp;
+	struct nameidata nd;
+	int		err;
+
+	/* Consistency check */
+	if (!exp_verify_string(nxp->ex_path, NFS_MAXPATHLEN) ||
+	    !exp_verify_string(nxp->ex_client, NFSCLNT_IDMAX))
+		return -EINVAL;
+
+	exp_writelock();
+
+	err = -EINVAL;
+	dom = auth_domain_find(nxp->ex_client);
+	if (!dom) {
+		dprintk("nfsd: unexport couldn't find %s\n", nxp->ex_client);
+		goto out_unlock;
+	}
+
+	err = path_lookup(nxp->ex_path, 0, &nd);
+	if (err)
+		goto out_domain;
+
+	err = -EINVAL;
+	exp = exp_get_by_name(dom, nd.mnt, nd.dentry, NULL);
+	path_release(&nd);
+	if (!exp)
+		goto out_domain;
+
+	exp_do_unexport(exp);
+	exp_put(exp);
+	err = 0;
+
+out_domain:
+	auth_domain_put(dom);
+	cache_flush();
+out_unlock:
+	exp_writeunlock();
+	return err;
+}
+
+/*
+ * Obtain the root fh on behalf of a client.
+ * This could be done in user space, but I feel that it adds some safety
+ * since its harder to fool a kernel module than a user space program.
+ */
+int
+exp_rootfh(svc_client *clp, char *path, struct knfsd_fh *f, int maxsize)
+{
+	struct svc_export	*exp;
+	struct nameidata	nd;
+	struct inode		*inode;
+	struct svc_fh		fh;
+	int			err;
+
+	err = -EPERM;
+	/* NB: we probably ought to check that it's NUL-terminated */
+	if (path_lookup(path, 0, &nd)) {
+		printk("nfsd: exp_rootfh path not found %s", path);
+		return err;
+	}
+	inode = nd.dentry->d_inode;
+
+	dprintk("nfsd: exp_rootfh(%s [%p] %s:%s/%ld)\n",
+		 path, nd.dentry, clp->name,
+		 inode->i_sb->s_id, inode->i_ino);
+	exp = exp_parent(clp, nd.mnt, nd.dentry, NULL);
+	if (!exp) {
+		dprintk("nfsd: exp_rootfh export not found.\n");
+		goto out;
+	}
+
+	/*
+	 * fh must be initialized before calling fh_compose
+	 */
+	fh_init(&fh, maxsize);
+	if (fh_compose(&fh, exp, nd.dentry, NULL))
+		err = -EINVAL;
+	else
+		err = 0;
+	memcpy(f, &fh.fh_handle, sizeof(struct knfsd_fh));
+	fh_put(&fh);
+	exp_put(exp);
+out:
+	path_release(&nd);
+	return err;
+}
+
+/*
+ * Called when we need the filehandle for the root of the pseudofs,
+ * for a given NFSv4 client.   The root is defined to be the
+ * export point with fsid==0
+ */
+int
+exp_pseudoroot(struct auth_domain *clp, struct svc_fh *fhp,
+	       struct cache_req *creq)
+{
+	struct svc_expkey *fsid_key;
+	int rv;
+	u32 fsidv[2];
+
+	mk_fsid_v1(fsidv, 0);
+
+	fsid_key = exp_find_key(clp, 1, fsidv, creq);
+	if (IS_ERR(fsid_key) && PTR_ERR(fsid_key) == -EAGAIN)
+		return nfserr_dropit;
+	if (!fsid_key || IS_ERR(fsid_key))
+		return nfserr_perm;
+
+	rv = fh_compose(fhp, fsid_key->ek_export, 
+			  fsid_key->ek_export->ex_dentry, NULL);
+	expkey_put(&fsid_key->h, &svc_expkey_cache);
+	return rv;
+}
+
+/* Iterator */
+
+static void *e_start(struct seq_file *m, loff_t *pos)
+{
+	loff_t n = *pos;
+	unsigned hash, export;
+	struct cache_head *ch;
+	
+	exp_readlock();
+	read_lock(&svc_export_cache.hash_lock);
+	if (!n--)
+		return (void *)1;
+	hash = n >> 32;
+	export = n & ((1LL<<32) - 1);
+
+	
+	for (ch=export_table[hash]; ch; ch=ch->next)
+		if (!export--)
+			return ch;
+	n &= ~((1LL<<32) - 1);
+	do {
+		hash++;
+		n += 1LL<<32;
+	} while(hash < EXPORT_HASHMAX && export_table[hash]==NULL);
+	if (hash >= EXPORT_HASHMAX)
+		return NULL;
+	*pos = n+1;
+	return export_table[hash];
+}
+
+static void *e_next(struct seq_file *m, void *p, loff_t *pos)
+{
+	struct cache_head *ch = p;
+	int hash = (*pos >> 32);
+
+	if (p == (void *)1)
+		hash = 0;
+	else if (ch->next == NULL) {
+		hash++;
+		*pos += 1LL<<32;
+	} else {
+		++*pos;
+		return ch->next;
+	}
+	*pos &= ~((1LL<<32) - 1);
+	while (hash < EXPORT_HASHMAX && export_table[hash] == NULL) {
+		hash++;
+		*pos += 1LL<<32;
+	}
+	if (hash >= EXPORT_HASHMAX)
+		return NULL;
+	++*pos;
+	return export_table[hash];
+}
+
+static void e_stop(struct seq_file *m, void *p)
+{
+	read_unlock(&svc_export_cache.hash_lock);
+	exp_readunlock();
+}
+
+static struct flags {
+	int flag;
+	char *name[2];
+} expflags[] = {
+	{ NFSEXP_READONLY, {"ro", "rw"}},
+	{ NFSEXP_INSECURE_PORT, {"insecure", ""}},
+	{ NFSEXP_ROOTSQUASH, {"root_squash", "no_root_squash"}},
+	{ NFSEXP_ALLSQUASH, {"all_squash", ""}},
+	{ NFSEXP_ASYNC, {"async", "sync"}},
+	{ NFSEXP_GATHERED_WRITES, {"wdelay", "no_wdelay"}},
+	{ NFSEXP_NOHIDE, {"nohide", ""}},
+	{ NFSEXP_CROSSMOUNT, {"crossmnt", ""}},
+	{ NFSEXP_NOSUBTREECHECK, {"no_subtree_check", ""}},
+	{ NFSEXP_NOAUTHNLM, {"insecure_locks", ""}},
+#ifdef MSNFS
+	{ NFSEXP_MSNFS, {"msnfs", ""}},
+#endif
+	{ 0, {"", ""}}
+};
+
+static void exp_flags(struct seq_file *m, int flag, int fsid, uid_t anonu, uid_t anong)
+{
+	int first = 0;
+	struct flags *flg;
+
+	for (flg = expflags; flg->flag; flg++) {
+		int state = (flg->flag & flag)?0:1;
+		if (*flg->name[state])
+			seq_printf(m, "%s%s", first++?",":"", flg->name[state]);
+	}
+	if (flag & NFSEXP_FSID)
+		seq_printf(m, "%sfsid=%d", first++?",":"", fsid);
+	if (anonu != (uid_t)-2 && anonu != (0x10000-2))
+		seq_printf(m, "%sanonuid=%d", first++?",":"", anonu);
+	if (anong != (gid_t)-2 && anong != (0x10000-2))
+		seq_printf(m, "%sanongid=%d", first++?",":"", anong);
+}
+
+static int e_show(struct seq_file *m, void *p)
+{
+	struct cache_head *cp = p;
+	struct svc_export *exp = container_of(cp, struct svc_export, h);
+	svc_client *clp;
+
+	if (p == (void *)1) {
+		seq_puts(m, "# Version 1.1\n");
+		seq_puts(m, "# Path Client(Flags) # IPs\n");
+		return 0;
+	}
+
+	clp = exp->ex_client;
+	cache_get(&exp->h);
+	if (cache_check(&svc_export_cache, &exp->h, NULL))
+		return 0;
+	if (cache_put(&exp->h, &svc_export_cache)) BUG();
+	return svc_export_show(m, &svc_export_cache, cp);
+}
+
+struct seq_operations nfs_exports_op = {
+	.start	= e_start,
+	.next	= e_next,
+	.stop	= e_stop,
+	.show	= e_show,
+};
+
+/*
+ * Add or modify a client.
+ * Change requests may involve the list of host addresses. The list of
+ * exports and possibly existing uid maps are left untouched.
+ */
+int
+exp_addclient(struct nfsctl_client *ncp)
+{
+	struct auth_domain	*dom;
+	int			i, err;
+
+	/* First, consistency check. */
+	err = -EINVAL;
+	if (! exp_verify_string(ncp->cl_ident, NFSCLNT_IDMAX))
+		goto out;
+	if (ncp->cl_naddr > NFSCLNT_ADDRMAX)
+		goto out;
+
+	/* Lock the hashtable */
+	exp_writelock();
+
+	dom = unix_domain_find(ncp->cl_ident);
+
+	err = -ENOMEM;
+	if (!dom)
+		goto out_unlock;
+
+	/* Insert client into hashtable. */
+	for (i = 0; i < ncp->cl_naddr; i++)
+		auth_unix_add_addr(ncp->cl_addrlist[i], dom);
+
+	auth_unix_forget_old(dom);
+	auth_domain_put(dom);
+
+	err = 0;
+
+out_unlock:
+	exp_writeunlock();
+out:
+	return err;
+}
+
+/*
+ * Delete a client given an identifier.
+ */
+int
+exp_delclient(struct nfsctl_client *ncp)
+{
+	int		err;
+	struct auth_domain *dom;
+
+	err = -EINVAL;
+	if (!exp_verify_string(ncp->cl_ident, NFSCLNT_IDMAX))
+		goto out;
+
+	/* Lock the hashtable */
+	exp_writelock();
+
+	dom = auth_domain_find(ncp->cl_ident);
+	/* just make sure that no addresses work 
+	 * and that it will expire soon 
+	 */
+	if (dom) {
+		err = auth_unix_forget_old(dom);
+		dom->h.expiry_time = get_seconds();
+		auth_domain_put(dom);
+	}
+
+	exp_writeunlock();
+out:
+	return err;
+}
+
+/*
+ * Verify that string is non-empty and does not exceed max length.
+ */
+static int
+exp_verify_string(char *cp, int max)
+{
+	int	i;
+
+	for (i = 0; i < max; i++)
+		if (!cp[i])
+			return i;
+	cp[i] = 0;
+	printk(KERN_NOTICE "nfsd: couldn't validate string %s\n", cp);
+	return 0;
+}
+
+/*
+ * Initialize the exports module.
+ */
+void
+nfsd_export_init(void)
+{
+	dprintk("nfsd: initializing export module.\n");
+
+	cache_register(&svc_export_cache);
+	cache_register(&svc_expkey_cache);
+
+}
+
+/*
+ * Flush exports table - called when last nfsd thread is killed
+ */
+void
+nfsd_export_flush(void)
+{
+	exp_writelock();
+	cache_purge(&svc_expkey_cache);
+	cache_purge(&svc_export_cache);
+	exp_writeunlock();
+}
+
+/*
+ * Shutdown the exports module.
+ */
+void
+nfsd_export_shutdown(void)
+{
+
+	dprintk("nfsd: shutting down export module.\n");
+
+	exp_writelock();
+
+	if (cache_unregister(&svc_expkey_cache))
+		printk(KERN_ERR "nfsd: failed to unregister expkey cache\n");
+	if (cache_unregister(&svc_export_cache))
+		printk(KERN_ERR "nfsd: failed to unregister export cache\n");
+	svcauth_unix_purge();
+
+	exp_writeunlock();
+	dprintk("nfsd: export shutdown complete.\n");
+}