3 files changed, 248 insertions, 37 deletions

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 460eeb329d81..752a367e0e3d 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -35,6 +35,7 @@
 #include <linux/file.h>
 #include <linux/slab.h>
 
+#include "idmap.h"
 #include "cache.h"
 #include "xdr4.h"
 #include "vfs.h"
@@ -1003,6 +1004,8 @@ static inline void nfsd4_increment_op_stats(u32 opnum)
 
 typedef __be32(*nfsd4op_func)(struct svc_rqst *, struct nfsd4_compound_state *,
                               void *);
+typedef u32(*nfsd4op_rsize)(struct svc_rqst *, struct nfsd4_op *op);
+
 enum nfsd4_op_flags {
         ALLOWED_WITHOUT_FH = 1 << 0,    /* No current filehandle required */
         ALLOWED_ON_ABSENT_FS = 1 << 1,  /* ops processed on absent fs */
@@ -1010,6 +1013,7 @@ enum nfsd4_op_flags {
         /* For rfc 5661 section 2.6.3.1.1: */
         OP_HANDLES_WRONGSEC = 1 << 3,
         OP_IS_PUTFH_LIKE = 1 << 4,
+        OP_MODIFIES_SOMETHING = 1 << 5, /* op is non-idempotent */
 };
 
 struct nfsd4_operation {
@@ -1025,6 +1029,8 @@ struct nfsd4_operation {
          * the v4.0 case).
          */
         bool op_cacheresult;
+        /* Try to get response size before operation */
+        nfsd4op_rsize op_rsize_bop;
 };
 
 static struct nfsd4_operation nfsd4_ops[];
@@ -1119,6 +1125,7 @@ nfsd4_proc_compound(struct svc_rqst *rqstp,
         struct nfsd4_operation *opdesc;
         struct nfsd4_compound_state *cstate = &resp->cstate;
         int             slack_bytes;
+        u32             plen = 0;
         __be32          status;
 
         resp->xbuf = &rqstp->rq_res;
@@ -1197,6 +1204,15 @@ nfsd4_proc_compound(struct svc_rqst *rqstp,
                         goto encode_op;
                 }
 
+                /* If op is non-idempotent */
+                if (opdesc->op_flags & OP_MODIFIES_SOMETHING) {
+                        plen = opdesc->op_rsize_bop(rqstp, op);
+                        op->status = nfsd4_check_resp_size(resp, plen);
+                }
+
+                if (op->status)
+                        goto encode_op;
+
                 if (opdesc->op_func)
                         op->status = opdesc->op_func(rqstp, cstate, &op->u);
                 else
@@ -1247,6 +1263,144 @@ out:
         return status;
 }
 
+#define op_encode_hdr_size              (2)
+#define op_encode_stateid_maxsz         (XDR_QUADLEN(NFS4_STATEID_SIZE))
+#define op_encode_verifier_maxsz        (XDR_QUADLEN(NFS4_VERIFIER_SIZE))
+#define op_encode_change_info_maxsz     (5)
+#define nfs4_fattr_bitmap_maxsz         (4)
+
+#define op_encode_lockowner_maxsz       (1 + XDR_QUADLEN(IDMAP_NAMESZ))
+#define op_encode_lock_denied_maxsz     (8 + op_encode_lockowner_maxsz)
+
+#define nfs4_owner_maxsz                (1 + XDR_QUADLEN(IDMAP_NAMESZ))
+
+#define op_encode_ace_maxsz             (3 + nfs4_owner_maxsz)
+#define op_encode_delegation_maxsz      (1 + op_encode_stateid_maxsz + 1 + \
+                                         op_encode_ace_maxsz)
+
+#define op_encode_channel_attrs_maxsz   (6 + 1 + 1)
+
+static inline u32 nfsd4_only_status_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        return (op_encode_hdr_size) * sizeof(__be32);
+}
+
+static inline u32 nfsd4_status_stateid_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        return (op_encode_hdr_size + op_encode_stateid_maxsz)* sizeof(__be32);
+}
+
+static inline u32 nfsd4_commit_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        return (op_encode_hdr_size + op_encode_verifier_maxsz) * sizeof(__be32);
+}
+
+static inline u32 nfsd4_create_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        return (op_encode_hdr_size + op_encode_change_info_maxsz
+                + nfs4_fattr_bitmap_maxsz) * sizeof(__be32);
+}
+
+static inline u32 nfsd4_link_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        return (op_encode_hdr_size + op_encode_change_info_maxsz)
+                * sizeof(__be32);
+}
+
+static inline u32 nfsd4_lock_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        return (op_encode_hdr_size + op_encode_lock_denied_maxsz)
+                * sizeof(__be32);
+}
+
+static inline u32 nfsd4_open_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        return (op_encode_hdr_size + op_encode_stateid_maxsz
+                + op_encode_change_info_maxsz + 1
+                + nfs4_fattr_bitmap_maxsz
+                + op_encode_delegation_maxsz) * sizeof(__be32);
+}
+
+static inline u32 nfsd4_read_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        u32 maxcount = 0, rlen = 0;
+
+        maxcount = svc_max_payload(rqstp);
+        rlen = op->u.read.rd_length;
+
+        if (rlen > maxcount)
+                rlen = maxcount;
+
+        return (op_encode_hdr_size + 2) * sizeof(__be32) + rlen;
+}
+
+static inline u32 nfsd4_readdir_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        u32 rlen = op->u.readdir.rd_maxcount;
+
+        if (rlen > PAGE_SIZE)
+                rlen = PAGE_SIZE;
+
+        return (op_encode_hdr_size + op_encode_verifier_maxsz)
+                 * sizeof(__be32) + rlen;
+}
+
+static inline u32 nfsd4_remove_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        return (op_encode_hdr_size + op_encode_change_info_maxsz)
+                * sizeof(__be32);
+}
+
+static inline u32 nfsd4_rename_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        return (op_encode_hdr_size + op_encode_change_info_maxsz
+                + op_encode_change_info_maxsz) * sizeof(__be32);
+}
+
+static inline u32 nfsd4_setattr_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        return (op_encode_hdr_size + nfs4_fattr_bitmap_maxsz) * sizeof(__be32);
+}
+
+static inline u32 nfsd4_setclientid_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        return (op_encode_hdr_size + 2 + 1024) * sizeof(__be32);
+}
+
+static inline u32 nfsd4_write_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        return (op_encode_hdr_size + op_encode_verifier_maxsz) * sizeof(__be32);
+}
+
+static inline u32 nfsd4_exchange_id_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        return (op_encode_hdr_size + 2 + 1 + /* eir_clientid, eir_sequenceid */\
+                1 + 1 + 0 + /* eir_flags, spr_how, SP4_NONE (for now) */\
+                2 + /*eir_server_owner.so_minor_id */\
+                /* eir_server_owner.so_major_id<> */\
+                XDR_QUADLEN(NFS4_OPAQUE_LIMIT) + 1 +\
+                /* eir_server_scope<> */\
+                XDR_QUADLEN(NFS4_OPAQUE_LIMIT) + 1 +\
+                1 + /* eir_server_impl_id array length */\
+                0 /* ignored eir_server_impl_id contents */) * sizeof(__be32);
+}
+
+static inline u32 nfsd4_bind_conn_to_session_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        return (op_encode_hdr_size + \
+                XDR_QUADLEN(NFS4_MAX_SESSIONID_LEN) + /* bctsr_sessid */\
+                2 /* bctsr_dir, use_conn_in_rdma_mode */) * sizeof(__be32);
+}
+
+static inline u32 nfsd4_create_session_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+        return (op_encode_hdr_size + \
+                XDR_QUADLEN(NFS4_MAX_SESSIONID_LEN) + /* sessionid */\
+                2 + /* csr_sequence, csr_flags */\
+                op_encode_channel_attrs_maxsz + \
+                op_encode_channel_attrs_maxsz) * sizeof(__be32);
+}
+
 static struct nfsd4_operation nfsd4_ops[] = {
         [OP_ACCESS] = {
                 .op_func = (nfsd4op_func)nfsd4_access,
@@ -1254,20 +1408,28 @@ static struct nfsd4_operation nfsd4_ops[] = {
         },
         [OP_CLOSE] = {
                 .op_func = (nfsd4op_func)nfsd4_close,
+                .op_flags = OP_MODIFIES_SOMETHING,
                 .op_name = "OP_CLOSE",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_status_stateid_rsize,
         },
         [OP_COMMIT] = {
                 .op_func = (nfsd4op_func)nfsd4_commit,
+                .op_flags = OP_MODIFIES_SOMETHING,
                 .op_name = "OP_COMMIT",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_commit_rsize,
         },
         [OP_CREATE] = {
                 .op_func = (nfsd4op_func)nfsd4_create,
+                .op_flags = OP_MODIFIES_SOMETHING,
                 .op_name = "OP_CREATE",
                 .op_cacheresult = true,
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_create_rsize,
         },
         [OP_DELEGRETURN] = {
                 .op_func = (nfsd4op_func)nfsd4_delegreturn,
+                .op_flags = OP_MODIFIES_SOMETHING,
                 .op_name = "OP_DELEGRETURN",
+                .op_rsize_bop = nfsd4_only_status_rsize,
         },
         [OP_GETATTR] = {
                 .op_func = (nfsd4op_func)nfsd4_getattr,
@@ -1280,12 +1442,16 @@ static struct nfsd4_operation nfsd4_ops[] = {
         },
         [OP_LINK] = {
                 .op_func = (nfsd4op_func)nfsd4_link,
+                .op_flags = ALLOWED_ON_ABSENT_FS | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_LINK",
                 .op_cacheresult = true,
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_link_rsize,
         },
         [OP_LOCK] = {
                 .op_func = (nfsd4op_func)nfsd4_lock,
+                .op_flags = OP_MODIFIES_SOMETHING,
                 .op_name = "OP_LOCK",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_lock_rsize,
         },
         [OP_LOCKT] = {
                 .op_func = (nfsd4op_func)nfsd4_lockt,
@@ -1293,7 +1459,9 @@ static struct nfsd4_operation nfsd4_ops[] = {
         },
         [OP_LOCKU] = {
                 .op_func = (nfsd4op_func)nfsd4_locku,
+                .op_flags = OP_MODIFIES_SOMETHING,
                 .op_name = "OP_LOCKU",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_status_stateid_rsize,
         },
         [OP_LOOKUP] = {
                 .op_func = (nfsd4op_func)nfsd4_lookup,
@@ -1311,42 +1479,54 @@ static struct nfsd4_operation nfsd4_ops[] = {
         },
         [OP_OPEN] = {
                 .op_func = (nfsd4op_func)nfsd4_open,
-                .op_flags = OP_HANDLES_WRONGSEC,
+                .op_flags = OP_HANDLES_WRONGSEC | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_OPEN",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_open_rsize,
         },
         [OP_OPEN_CONFIRM] = {
                 .op_func = (nfsd4op_func)nfsd4_open_confirm,
+                .op_flags = OP_MODIFIES_SOMETHING,
                 .op_name = "OP_OPEN_CONFIRM",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_status_stateid_rsize,
         },
         [OP_OPEN_DOWNGRADE] = {
                 .op_func = (nfsd4op_func)nfsd4_open_downgrade,
+                .op_flags = OP_MODIFIES_SOMETHING,
                 .op_name = "OP_OPEN_DOWNGRADE",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_status_stateid_rsize,
         },
         [OP_PUTFH] = {
                 .op_func = (nfsd4op_func)nfsd4_putfh,
                 .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS
-                                | OP_IS_PUTFH_LIKE,
+                                | OP_IS_PUTFH_LIKE | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_PUTFH",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,
         },
         [OP_PUTPUBFH] = {
                 .op_func = (nfsd4op_func)nfsd4_putrootfh,
                 .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS
-                                | OP_IS_PUTFH_LIKE,
+                                | OP_IS_PUTFH_LIKE | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_PUTPUBFH",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,
         },
         [OP_PUTROOTFH] = {
                 .op_func = (nfsd4op_func)nfsd4_putrootfh,
                 .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS
-                                | OP_IS_PUTFH_LIKE,
+                                | OP_IS_PUTFH_LIKE | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_PUTROOTFH",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,
         },
         [OP_READ] = {
                 .op_func = (nfsd4op_func)nfsd4_read,
+                .op_flags = OP_MODIFIES_SOMETHING,
                 .op_name = "OP_READ",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_read_rsize,
         },
         [OP_READDIR] = {
                 .op_func = (nfsd4op_func)nfsd4_readdir,
+                .op_flags = OP_MODIFIES_SOMETHING,
                 .op_name = "OP_READDIR",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_readdir_rsize,
         },
         [OP_READLINK] = {
                 .op_func = (nfsd4op_func)nfsd4_readlink,
@@ -1354,29 +1534,38 @@ static struct nfsd4_operation nfsd4_ops[] = {
         },
         [OP_REMOVE] = {
                 .op_func = (nfsd4op_func)nfsd4_remove,
+                .op_flags = OP_MODIFIES_SOMETHING,
                 .op_name = "OP_REMOVE",
                 .op_cacheresult = true,
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_remove_rsize,
         },
         [OP_RENAME] = {
-                .op_name = "OP_RENAME",
                 .op_func = (nfsd4op_func)nfsd4_rename,
+                .op_flags = OP_MODIFIES_SOMETHING,
+                .op_name = "OP_RENAME",
                 .op_cacheresult = true,
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_rename_rsize,
         },
         [OP_RENEW] = {
                 .op_func = (nfsd4op_func)nfsd4_renew,
-                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
+                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS
+                                | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_RENEW",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,
+
         },
         [OP_RESTOREFH] = {
                 .op_func = (nfsd4op_func)nfsd4_restorefh,
                 .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS
-                                | OP_IS_PUTFH_LIKE,
+                                | OP_IS_PUTFH_LIKE | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_RESTOREFH",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,
         },
         [OP_SAVEFH] = {
                 .op_func = (nfsd4op_func)nfsd4_savefh,
-                .op_flags = OP_HANDLES_WRONGSEC,
+                .op_flags = OP_HANDLES_WRONGSEC | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_SAVEFH",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,
         },
         [OP_SECINFO] = {
                 .op_func = (nfsd4op_func)nfsd4_secinfo,
@@ -1386,19 +1575,25 @@ static struct nfsd4_operation nfsd4_ops[] = {
         [OP_SETATTR] = {
                 .op_func = (nfsd4op_func)nfsd4_setattr,
                 .op_name = "OP_SETATTR",
+                .op_flags = OP_MODIFIES_SOMETHING,
                 .op_cacheresult = true,
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_setattr_rsize,
         },
         [OP_SETCLIENTID] = {
                 .op_func = (nfsd4op_func)nfsd4_setclientid,
-                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
+                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS
+                                | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_SETCLIENTID",
                 .op_cacheresult = true,
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_setclientid_rsize,
         },
         [OP_SETCLIENTID_CONFIRM] = {
                 .op_func = (nfsd4op_func)nfsd4_setclientid_confirm,
-                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
+                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS
+                                | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_SETCLIENTID_CONFIRM",
                 .op_cacheresult = true,
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,
         },
         [OP_VERIFY] = {
                 .op_func = (nfsd4op_func)nfsd4_verify,
@@ -1406,35 +1601,47 @@ static struct nfsd4_operation nfsd4_ops[] = {
         },
         [OP_WRITE] = {
                 .op_func = (nfsd4op_func)nfsd4_write,
+                .op_flags = OP_MODIFIES_SOMETHING,
                 .op_name = "OP_WRITE",
                 .op_cacheresult = true,
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_write_rsize,
         },
         [OP_RELEASE_LOCKOWNER] = {
                 .op_func = (nfsd4op_func)nfsd4_release_lockowner,
-                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
+                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS
+                                | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_RELEASE_LOCKOWNER",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,
         },
 
         /* NFSv4.1 operations */
         [OP_EXCHANGE_ID] = {
                 .op_func = (nfsd4op_func)nfsd4_exchange_id,
-                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_AS_FIRST_OP,
+                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_AS_FIRST_OP
+                                | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_EXCHANGE_ID",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_exchange_id_rsize,
         },
         [OP_BIND_CONN_TO_SESSION] = {
                 .op_func = (nfsd4op_func)nfsd4_bind_conn_to_session,
-                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_AS_FIRST_OP,
+                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_AS_FIRST_OP
+                                | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_BIND_CONN_TO_SESSION",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_bind_conn_to_session_rsize,
         },
         [OP_CREATE_SESSION] = {
                 .op_func = (nfsd4op_func)nfsd4_create_session,
-                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_AS_FIRST_OP,
+                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_AS_FIRST_OP
+                                | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_CREATE_SESSION",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_create_session_rsize,
         },
         [OP_DESTROY_SESSION] = {
                 .op_func = (nfsd4op_func)nfsd4_destroy_session,
-                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_AS_FIRST_OP,
+                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_AS_FIRST_OP
+                                | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_DESTROY_SESSION",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,
         },
         [OP_SEQUENCE] = {
                 .op_func = (nfsd4op_func)nfsd4_sequence,
@@ -1443,13 +1650,16 @@ static struct nfsd4_operation nfsd4_ops[] = {
         },
         [OP_DESTROY_CLIENTID] = {
                 .op_func = NULL,
-                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_AS_FIRST_OP,
+                .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_AS_FIRST_OP
+                                | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_DESTROY_CLIENTID",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,
         },
         [OP_RECLAIM_COMPLETE] = {
                 .op_func = (nfsd4op_func)nfsd4_reclaim_complete,
-                .op_flags = ALLOWED_WITHOUT_FH,
+                .op_flags = ALLOWED_WITHOUT_FH | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_RECLAIM_COMPLETE",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,
         },
         [OP_SECINFO_NO_NAME] = {
                 .op_func = (nfsd4op_func)nfsd4_secinfo_no_name,
@@ -1463,8 +1673,9 @@ static struct nfsd4_operation nfsd4_ops[] = {
         },
         [OP_FREE_STATEID] = {
                 .op_func = (nfsd4op_func)nfsd4_free_stateid,
-                .op_flags = ALLOWED_WITHOUT_FH,
+                .op_flags = ALLOWED_WITHOUT_FH | OP_MODIFIES_SOMETHING,
                 .op_name = "OP_FREE_STATEID",
+                .op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,
         },
 };
 
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 5252d6681960..f4116cf16595 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -3387,34 +3387,29 @@ static nfsd4_enc nfsd4_enc_ops[] = {
 
 /*
  * Calculate the total amount of memory that the compound response has taken
- * after encoding the current operation.
+ * after encoding the current operation with pad.
  *
- * pad: add on 8 bytes for the next operation's op_code and status so that
- * there is room to cache a failure on the next operation.
+ * pad: if operation is non-idempotent, pad was calculate by op_rsize_bop()
+ *      which was specified at nfsd4_operation, else pad is zero.
  *
- * Compare this length to the session se_fmaxresp_cached.
+ * Compare this length to the session se_fmaxresp_sz and se_fmaxresp_cached.
  *
  * Our se_fmaxresp_cached will always be a multiple of PAGE_SIZE, and so
  * will be at least a page and will therefore hold the xdr_buf head.
  */
-static int nfsd4_check_drc_limit(struct nfsd4_compoundres *resp)
+int nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 pad)
 {
-        int status = 0;
         struct xdr_buf *xb = &resp->rqstp->rq_res;
-        struct nfsd4_compoundargs *args = resp->rqstp->rq_argp;
         struct nfsd4_session *session = NULL;
         struct nfsd4_slot *slot = resp->cstate.slot;
-        u32 length, tlen = 0, pad = 8;
+        u32 length, tlen = 0;
 
         if (!nfsd4_has_session(&resp->cstate))
-                return status;
+                return 0;
 
         session = resp->cstate.session;
-        if (session == NULL || slot->sl_cachethis == 0)
-                return status;
-
-        if (resp->opcnt >= args->opcnt)
-                pad = 0; /* this is the last operation */
+        if (session == NULL)
+                return 0;
 
         if (xb->page_len == 0) {
                 length = (char *)resp->p - (char *)xb->head[0].iov_base + pad;
@@ -3427,10 +3422,14 @@ static int nfsd4_check_drc_limit(struct nfsd4_compoundres *resp)
         dprintk("%s length %u, xb->page_len %u tlen %u pad %u\n", __func__,
                 length, xb->page_len, tlen, pad);
 
-        if (length <= session->se_fchannel.maxresp_cached)
-                return status;
-        else
+        if (length > session->se_fchannel.maxresp_sz)
+                return nfserr_rep_too_big;
+
+        if (slot->sl_cachethis == 1 &&
+            length > session->se_fchannel.maxresp_cached)
                 return nfserr_rep_too_big_to_cache;
+
+        return 0;
 }
 
 void
@@ -3450,8 +3449,8 @@ nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
                !nfsd4_enc_ops[op->opnum]);
         op->status = nfsd4_enc_ops[op->opnum](resp, op->status, &op->u);
         /* nfsd4_check_drc_limit guarantees enough room for error status */
-        if (!op->status && nfsd4_check_drc_limit(resp))
-                op->status = nfserr_rep_too_big_to_cache;
+        if (!op->status)
+                op->status = nfsd4_check_resp_size(resp, 0);
 status:
         /*
          * Note: We write the status directly, instead of using WRITE32(),
diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h
index f95a72482064..a767b57b8208 100644
--- a/fs/nfsd/xdr4.h
+++ b/fs/nfsd/xdr4.h
@@ -524,6 +524,7 @@ int nfs4svc_decode_compoundargs(struct svc_rqst *, __be32 *,
                 struct nfsd4_compoundargs *);
 int nfs4svc_encode_compoundres(struct svc_rqst *, __be32 *,
                 struct nfsd4_compoundres *);
+int nfsd4_check_resp_size(struct nfsd4_compoundres *, u32);
 void nfsd4_encode_operation(struct nfsd4_compoundres *, struct nfsd4_op *);
 void nfsd4_encode_replay(struct nfsd4_compoundres *resp, struct nfsd4_op *op);
 __be32 nfsd4_encode_fattr(struct svc_fh *fhp, struct svc_export *exp,