NFS: Simplify ->decode_dirent() calling sequence

Clean up.

The pointer returned by ->decode_dirent() is no longer used as a
pointer.  The only call site (xdr_decode() in fs/nfs/dir.c) simply
extracts the errno value encoded in the pointer.  Replace the
returned pointer with a standard integer errno return value.

Also, pass the "server" argument as part of the nfs_entry instead of
as a separate parameter.  It's faster to derive "server" in
nfs_readdir_xdr_to_array() since we already have the directory's inode
handy.  "server" ought to be invariant for a set of entries in the
same directory, right?

The legacy versions of decode_dirent() don't use "server" anyway, so
it's wasted work for them to derive and pass "server" for each entry.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 8 insertions, 7 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 996dd8989a91..3e2123fe79f5 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -172,7 +172,7 @@ struct nfs_cache_array {
 	struct nfs_cache_array_entry array[0];
 };
 
-typedef __be32 * (*decode_dirent_t)(struct xdr_stream *, struct nfs_entry *, struct nfs_server *, int);
+typedef int (*decode_dirent_t)(struct xdr_stream *, struct nfs_entry *, int);
 typedef struct {
 	struct file	*file;
 	struct page	*page;
@@ -378,14 +378,14 @@ error:
 	return error;
 }
 
-/* Fill in an entry based on the xdr code stored in desc->page */
-static
-int xdr_decode(nfs_readdir_descriptor_t *desc, struct nfs_entry *entry, struct xdr_stream *stream)
+static int xdr_decode(nfs_readdir_descriptor_t *desc,
+		      struct nfs_entry *entry, struct xdr_stream *xdr)
 {
-	__be32 *p = desc->decode(stream, entry, NFS_SERVER(desc->file->f_path.dentry->d_inode), desc->plus);
-	if (IS_ERR(p))
-		return PTR_ERR(p);
+	int error;
 
+	error = desc->decode(xdr, entry, desc->plus);
+	if (error)
+		return error;
 	entry->fattr->time_start = desc->timestamp;
 	entry->fattr->gencount = desc->gencount;
 	return 0;
@@ -566,6 +566,7 @@ int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page,
 	entry.eof = 0;
 	entry.fh = nfs_alloc_fhandle();
 	entry.fattr = nfs_alloc_fattr();
+	entry.server = NFS_SERVER(inode);
 	if (entry.fh == NULL || entry.fattr == NULL)
 		goto out;