NFSD: Add nfsd4_encode_fattr4_fsid()

Refactor the encoder for FATTR4_FSID into a helper. In a subsequent
patch, this helper will be called from a bitmask loop.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index d08e0dbe3dd4ed0073e45b0a4f6d76a7f8a6ccf5..aa3081ef65c56d354003865a00513c8fb6beb73a 100644 (file)
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -3031,6 +3031,39 @@ static __be32 nfsd4_encode_fattr4_size(struct xdr_stream *xdr,
        return nfsd4_encode_uint64_t(xdr, args->size);
 }
 
+static __be32 nfsd4_encode_fattr4_fsid(struct xdr_stream *xdr,
+                                      const struct nfsd4_fattr_args *args)
+{
+       __be32 *p;
+
+       p = xdr_reserve_space(xdr, XDR_UNIT * 2 + XDR_UNIT * 2);
+       if (!p)
+               return nfserr_resource;
+
+       if (unlikely(args->exp->ex_fslocs.migrated)) {
+               p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MAJOR);
+               xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MINOR);
+               return nfs_ok;
+       }
+       switch (fsid_source(args->fhp)) {
+       case FSIDSOURCE_FSID:
+               p = xdr_encode_hyper(p, (u64)args->exp->ex_fsid);
+               xdr_encode_hyper(p, (u64)0);
+               break;
+       case FSIDSOURCE_DEV:
+               *p++ = xdr_zero;
+               *p++ = cpu_to_be32(MAJOR(args->stat.dev));
+               *p++ = xdr_zero;
+               *p   = cpu_to_be32(MINOR(args->stat.dev));
+               break;
+       case FSIDSOURCE_UUID:
+               xdr_encode_opaque_fixed(p, args->exp->ex_uuid, EX_UUID_LEN);
+               break;
+       }
+
+       return nfs_ok;
+}
+
 /*
  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
  * ourselves.
@@ -3201,28 +3234,9 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
                        goto out;
        }
        if (bmval0 & FATTR4_WORD0_FSID) {
-               p = xdr_reserve_space(xdr, 16);
-               if (!p)
-                       goto out_resource;
-               if (exp->ex_fslocs.migrated) {
-                       p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MAJOR);
-                       p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MINOR);
-               } else switch (fsid_source(args.fhp)) {
-               case FSIDSOURCE_FSID:
-                       p = xdr_encode_hyper(p, (u64)exp->ex_fsid);
-                       p = xdr_encode_hyper(p, (u64)0);
-                       break;
-               case FSIDSOURCE_DEV:
-                       *p++ = cpu_to_be32(0);
-                       *p++ = cpu_to_be32(MAJOR(args.stat.dev));
-                       *p++ = cpu_to_be32(0);
-                       *p++ = cpu_to_be32(MINOR(args.stat.dev));
-                       break;
-               case FSIDSOURCE_UUID:
-                       p = xdr_encode_opaque_fixed(p, exp->ex_uuid,
-                                                               EX_UUID_LEN);
-                       break;
-               }
+               status = nfsd4_encode_fattr4_fsid(xdr, &args);
+               if (status != nfs_ok)
+                       goto out;
        }
        if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
                status = nfsd4_encode_fattr4__false(xdr, &args);