nfsd: pass pointer to export cache down to stack wherever possible.

This cache will be per-net soon. And it's easier to get the pointer to desired
per-net instance only once and then pass it down instead of discovering it in
every place were required.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

fs/nfsd/export.c

@@ -785,8 +785,8 @@ exp_find_key(struct cache_detail *cd, svc_client *clp, int fsid_type,
 }
 
 
-static svc_export *exp_get_by_name(svc_client *clp, const struct path *path,
-				     struct cache_req *reqp)
+static svc_export *exp_get_by_name(struct cache_detail *cd, svc_client *clp,
+				   const struct path *path, struct cache_req *reqp)
 {
 	struct svc_export *exp, key;
 	int err;
@@ -796,12 +796,12 @@ static svc_export *exp_get_by_name(svc_client *clp, const struct path *path,
 
 	key.ex_client = clp;
 	key.ex_path = *path;
-	key.cd = &svc_export_cache;
+	key.cd = cd;
 
 	exp = svc_export_lookup(&key);
 	if (exp == NULL)
 		return ERR_PTR(-ENOMEM);
-	err = cache_check(&svc_export_cache, &exp->h, reqp);
+	err = cache_check(cd, &exp->h, reqp);
 	if (err)
 		return ERR_PTR(err);
 	return exp;
@@ -810,16 +810,17 @@ static svc_export *exp_get_by_name(svc_client *clp, const struct path *path,
 /*
  * Find the export entry for a given dentry.
  */
-static struct svc_export *exp_parent(svc_client *clp, struct path *path)
+static struct svc_export *exp_parent(struct cache_detail *cd, svc_client *clp,
+				     struct path *path)
 {
 	struct dentry *saved = dget(path->dentry);
-	svc_export *exp = exp_get_by_name(clp, path, NULL);
+	svc_export *exp = exp_get_by_name(cd, clp, path, NULL);
 
 	while (PTR_ERR(exp) == -ENOENT && !IS_ROOT(path->dentry)) {
 		struct dentry *parent = dget_parent(path->dentry);
 		dput(path->dentry);
 		path->dentry = parent;
-		exp = exp_get_by_name(clp, path, NULL);
+		exp = exp_get_by_name(cd, clp, path, NULL);
 	}
 	dput(path->dentry);
 	path->dentry = saved;
@@ -834,13 +835,15 @@ static struct svc_export *exp_parent(svc_client *clp, struct path *path)
  * since its harder to fool a kernel module than a user space program.
  */
 int
-exp_rootfh(svc_client *clp, char *name, struct knfsd_fh *f, int maxsize)
+exp_rootfh(svc_client *clp, char *name,
+	   struct knfsd_fh *f, int maxsize)
 {
 	struct svc_export	*exp;
 	struct path		path;
 	struct inode		*inode;
 	struct svc_fh		fh;
 	int			err;
+	struct cache_detail	*cd = &svc_export_cache;
 
 	err = -EPERM;
 	/* NB: we probably ought to check that it's NUL-terminated */
@@ -853,7 +856,7 @@ exp_rootfh(svc_client *clp, char *name, struct knfsd_fh *f, int maxsize)
 	dprintk("nfsd: exp_rootfh(%s [%p] %s:%s/%ld)\n",
 		 name, path.dentry, clp->name,
 		 inode->i_sb->s_id, inode->i_ino);
-	exp = exp_parent(clp, &path);
+	exp = exp_parent(cd, clp, &path);
 	if (IS_ERR(exp)) {
 		err = PTR_ERR(exp);
 		goto out;
@@ -875,7 +878,8 @@ exp_rootfh(svc_client *clp, char *name, struct knfsd_fh *f, int maxsize)
 	return err;
 }
 
-static struct svc_export *exp_find(struct auth_domain *clp, int fsid_type,
+static struct svc_export *exp_find(struct cache_detail *cd,
+				   struct auth_domain *clp, int fsid_type,
 				   u32 *fsidv, struct cache_req *reqp)
 {
 	struct svc_export *exp;
@@ -883,7 +887,7 @@ static struct svc_export *exp_find(struct auth_domain *clp, int fsid_type,
 	if (IS_ERR(ek))
 		return ERR_CAST(ek);
 
-	exp = exp_get_by_name(clp, &ek->ek_path, reqp);
+	exp = exp_get_by_name(cd, clp, &ek->ek_path, reqp);
 	cache_put(&ek->h, &svc_expkey_cache);
 
 	if (IS_ERR(exp))
@@ -926,12 +930,13 @@ struct svc_export *
 rqst_exp_get_by_name(struct svc_rqst *rqstp, struct path *path)
 {
 	struct svc_export *gssexp, *exp = ERR_PTR(-ENOENT);
+	struct cache_detail *cd = &svc_export_cache;
 
 	if (rqstp->rq_client == NULL)
 		goto gss;
 
 	/* First try the auth_unix client: */
-	exp = exp_get_by_name(rqstp->rq_client, path, &rqstp->rq_chandle);
+	exp = exp_get_by_name(cd, rqstp->rq_client, path, &rqstp->rq_chandle);
 	if (PTR_ERR(exp) == -ENOENT)
 		goto gss;
 	if (IS_ERR(exp))
@@ -943,7 +948,7 @@ rqst_exp_get_by_name(struct svc_rqst *rqstp, struct path *path)
 	/* Otherwise, try falling back on gss client */
 	if (rqstp->rq_gssclient == NULL)
 		return exp;
-	gssexp = exp_get_by_name(rqstp->rq_gssclient, path, &rqstp->rq_chandle);
+	gssexp = exp_get_by_name(cd, rqstp->rq_gssclient, path, &rqstp->rq_chandle);
 	if (PTR_ERR(gssexp) == -ENOENT)
 		return exp;
 	if (!IS_ERR(exp))
@@ -955,12 +960,14 @@ struct svc_export *
 rqst_exp_find(struct svc_rqst *rqstp, int fsid_type, u32 *fsidv)
 {
 	struct svc_export *gssexp, *exp = ERR_PTR(-ENOENT);
+	struct cache_detail *cd = &svc_export_cache;
 
 	if (rqstp->rq_client == NULL)
 		goto gss;
 
 	/* First try the auth_unix client: */
-	exp = exp_find(rqstp->rq_client, fsid_type, fsidv, &rqstp->rq_chandle);
+	exp = exp_find(cd, rqstp->rq_client, fsid_type,
+		       fsidv, &rqstp->rq_chandle);
 	if (PTR_ERR(exp) == -ENOENT)
 		goto gss;
 	if (IS_ERR(exp))
@@ -972,7 +979,7 @@ rqst_exp_find(struct svc_rqst *rqstp, int fsid_type, u32 *fsidv)
 	/* Otherwise, try falling back on gss client */
 	if (rqstp->rq_gssclient == NULL)
 		return exp;
-	gssexp = exp_find(rqstp->rq_gssclient, fsid_type, fsidv,
+	gssexp = exp_find(cd, rqstp->rq_gssclient, fsid_type, fsidv,
 						&rqstp->rq_chandle);
 	if (PTR_ERR(gssexp) == -ENOENT)
 		return exp;