nfsd: move some of fh_compose into helper functions

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

1 files changed, 45 insertions, 38 deletions

diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c
index 8847f3fbfc1e..78d8ebf162ca 100644
--- a/fs/nfsd/nfsfh.c
+++ b/fs/nfsd/nfsfh.c
@@ -397,6 +397,40 @@ static inline void _fh_update_old(struct dentry *dentry,
                 fh->ofh_dirino = 0;
 }
 
+static bool is_root_export(struct svc_export *exp)
+{
+        return exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root;
+}
+
+static struct super_block *exp_sb(struct svc_export *exp)
+{
+        return exp->ex_path.dentry->d_inode->i_sb;
+}
+
+static bool fsid_type_ok_for_exp(u8 fsid_type, struct svc_export *exp)
+{
+        switch (fsid_type) {
+        case FSID_DEV:
+                if (!old_valid_dev(exp_sb(exp)->s_dev))
+                        return 0;
+                /* FALL THROUGH */
+        case FSID_MAJOR_MINOR:
+        case FSID_ENCODE_DEV:
+                return exp_sb(exp)->s_type->fs_flags & FS_REQUIRES_DEV;
+        case FSID_NUM:
+                return exp->ex_flags & NFSEXP_FSID;
+        case FSID_UUID8:
+        case FSID_UUID16:
+                if (!is_root_export(exp))
+                        return 0;
+                /* fall through */
+        case FSID_UUID4_INUM:
+        case FSID_UUID16_INUM:
+                return exp->ex_uuid != NULL;
+        }
+        return 1;
+}
+
 __be32
 fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry,
            struct svc_fh *ref_fh)
@@ -414,8 +448,7 @@ fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry,
         struct inode * inode = dentry->d_inode;
         struct dentry *parent = dentry->d_parent;
         __u32 *datap;
-        dev_t ex_dev = exp->ex_path.dentry->d_inode->i_sb->s_dev;
-        int root_export = (exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root);
+        dev_t ex_dev = exp_sb(exp)->s_dev;
 
         dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %s/%s, ino=%ld)\n",
                 MAJOR(ex_dev), MINOR(ex_dev),
@@ -447,49 +480,24 @@ fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry,
                         goto retry;
                 }
 
-                /* Need to check that this type works for this
-                 * export point.  As the fsid -> filesystem mapping
-                 * was guided by user-space, there is no guarantee
-                 * that the filesystem actually supports that fsid
-                 * type. If it doesn't we loop around again without
-                 * ref_fh set.
+                /*
+                 * As the fsid -> filesystem mapping was guided by
+                 * user-space, there is no guarantee that the filesystem
+                 * actually supports that fsid type. If it doesn't we
+                 * loop around again without ref_fh set.
                  */
-                switch(fsid_type) {
-                case FSID_DEV:
-                        if (!old_valid_dev(ex_dev))
-                                goto retry;
-                        /* FALL THROUGH */
-                case FSID_MAJOR_MINOR:
-                case FSID_ENCODE_DEV:
-                        if (!(exp->ex_path.dentry->d_inode->i_sb->s_type->fs_flags
-                              & FS_REQUIRES_DEV))
-                                goto retry;
-                        break;
-                case FSID_NUM:
-                        if (! (exp->ex_flags & NFSEXP_FSID))
-                                goto retry;
-                        break;
-                case FSID_UUID8:
-                case FSID_UUID16:
-                        if (!root_export)
-                                goto retry;
-                        /* fall through */
-                case FSID_UUID4_INUM:
-                case FSID_UUID16_INUM:
-                        if (exp->ex_uuid == NULL)
-                                goto retry;
-                        break;
-                }
+                if (!fsid_type_ok_for_exp(fsid_type, exp))
+                        goto retry;
         } else if (exp->ex_flags & NFSEXP_FSID) {
                 fsid_type = FSID_NUM;
         } else if (exp->ex_uuid) {
                 if (fhp->fh_maxsize >= 64) {
-                        if (root_export)
+                        if (is_root_export(exp))
                                 fsid_type = FSID_UUID16;
                         else
                                 fsid_type = FSID_UUID16_INUM;
                 } else {
-                        if (root_export)
+                        if (is_root_export(exp))
                                 fsid_type = FSID_UUID8;
                         else
                                 fsid_type = FSID_UUID4_INUM;
@@ -639,8 +647,7 @@ enum fsid_source fsid_source(struct svc_fh *fhp)
         case FSID_DEV:
         case FSID_ENCODE_DEV:
         case FSID_MAJOR_MINOR:
-                if (fhp->fh_export->ex_path.dentry->d_inode->i_sb->s_type->fs_flags
-                    & FS_REQUIRES_DEV)
+                if (exp_sb(fhp->fh_export)->s_type->fs_flags & FS_REQUIRES_DEV)
                         return FSIDSOURCE_DEV;
                 break;
         case FSID_NUM: