NFSD: Clean up the test_stateid function

When I initially wrote it, I didn't understand how lists worked so I
wrote something that didn't use them.  I think making a list of stateids
to test is a more straightforward implementation, especially compared to
especially compared to decoding stateids while simultaneously encoding
a reply to the client.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

3 files changed, 35 insertions, 49 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 45966a436b0a..f1b74a74ec49 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -3402,7 +3402,14 @@ __be32
 nfsd4_test_stateid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
                    struct nfsd4_test_stateid *test_stateid)
 {
-        /* real work is done during encoding */
+        struct nfsd4_test_stateid_id *stateid;
+        struct nfs4_client *cl = cstate->session->se_client;
+
+        nfs4_lock_state();
+        list_for_each_entry(stateid, &test_stateid->ts_stateid_list, ts_id_list)
+                stateid->ts_id_status = nfs4_validate_stateid(cl, &stateid->ts_id_stateid);
+        nfs4_unlock_state();
+
         return nfs_ok;
 }
 
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index d241a8571ddf..a58f2064f479 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -133,22 +133,6 @@ xdr_error:					\
         }                                       \
 } while (0)
 
-static void save_buf(struct nfsd4_compoundargs *argp, struct nfsd4_saved_compoundargs *savep)
-{
-        savep->p        = argp->p;
-        savep->end      = argp->end;
-        savep->pagelen  = argp->pagelen;
-        savep->pagelist = argp->pagelist;
-}
-
-static void restore_buf(struct nfsd4_compoundargs *argp, struct nfsd4_saved_compoundargs *savep)
-{
-        argp->p        = savep->p;
-        argp->end      = savep->end;
-        argp->pagelen  = savep->pagelen;
-        argp->pagelist = savep->pagelist;
-}
-
 static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes)
 {
         /* We want more bytes than seem to be available.
@@ -1396,26 +1380,29 @@ nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
 static __be32
 nfsd4_decode_test_stateid(struct nfsd4_compoundargs *argp, struct nfsd4_test_stateid *test_stateid)
 {
-        unsigned int nbytes;
-        stateid_t si;
         int i;
-        __be32 *p;
-        __be32 status;
+        __be32 *p, status;
+        struct nfsd4_test_stateid_id *stateid;
 
         READ_BUF(4);
         test_stateid->ts_num_ids = ntohl(*p++);
 
-        nbytes = test_stateid->ts_num_ids * sizeof(stateid_t);
-        if (nbytes > (u32)((char *)argp->end - (char *)argp->p))
-                goto xdr_error;
-
-        test_stateid->ts_saved_args = argp;
-        save_buf(argp, &test_stateid->ts_savedp);
+        INIT_LIST_HEAD(&test_stateid->ts_stateid_list);
 
         for (i = 0; i < test_stateid->ts_num_ids; i++) {
-                status = nfsd4_decode_stateid(argp, &si);
+                stateid = kmalloc(sizeof(struct nfsd4_test_stateid_id), GFP_KERNEL);
+                if (!stateid) {
+                        status = PTR_ERR(stateid);
+                        goto out;
+                }
+
+                defer_free(argp, kfree, stateid);
+                INIT_LIST_HEAD(&stateid->ts_id_list);
+                list_add_tail(&stateid->ts_id_list, &test_stateid->ts_stateid_list);
+
+                status = nfsd4_decode_stateid(argp, &stateid->ts_id_stateid);
                 if (status)
-                        return status;
+                        goto out;
         }
 
         status = 0;
@@ -3402,30 +3389,17 @@ __be32
 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, int nfserr,
                           struct nfsd4_test_stateid *test_stateid)
 {
-        struct nfsd4_compoundargs *argp;
-        struct nfs4_client *cl = resp->cstate.session->se_client;
-        stateid_t si;
+        struct nfsd4_test_stateid_id *stateid, *next;
         __be32 *p;
-        int i;
-        int valid;
 
-        restore_buf(test_stateid->ts_saved_args, &test_stateid->ts_savedp);
-        argp = test_stateid->ts_saved_args;
-
-        RESERVE_SPACE(4);
+        RESERVE_SPACE(4 + (4 * test_stateid->ts_num_ids));
         *p++ = htonl(test_stateid->ts_num_ids);
-        resp->p = p;
 
-        nfs4_lock_state();
-        for (i = 0; i < test_stateid->ts_num_ids; i++) {
-                nfsd4_decode_stateid(argp, &si);
-                valid = nfs4_validate_stateid(cl, &si);
-                RESERVE_SPACE(4);
-                *p++ = htonl(valid);
-                resp->p = p;
+        list_for_each_entry_safe(stateid, next, &test_stateid->ts_stateid_list, ts_id_list) {
+                *p++ = htonl(stateid->ts_id_status);
         }
-        nfs4_unlock_state();
 
+        ADJUST_ARGS();
         return nfserr;
 }
 
diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h
index 4949832fd74a..7110a082275f 100644
--- a/fs/nfsd/xdr4.h
+++ b/fs/nfsd/xdr4.h
@@ -356,10 +356,15 @@ struct nfsd4_saved_compoundargs {
         struct page **pagelist;
 };
 
+struct nfsd4_test_stateid_id {
+        __be32                  ts_id_status;
+        stateid_t               ts_id_stateid;
+        struct list_head        ts_id_list;
+};
+
 struct nfsd4_test_stateid {
         __be32          ts_num_ids;
-        struct nfsd4_compoundargs *ts_saved_args;
-        struct nfsd4_saved_compoundargs ts_savedp;
+        struct list_head ts_stateid_list;
 };
 
 struct nfsd4_free_stateid {