1 files changed, 37 insertions, 30 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index f5f82e145018..70d0b9b33031 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -3480,12 +3480,17 @@ alloc_init_open_stateowner(unsigned int strhashval, struct nfsd4_open *open,
 }
 
 static struct nfs4_ol_stateid *
-init_open_stateid(struct nfs4_ol_stateid *stp, struct nfs4_file *fp,
-                struct nfsd4_open *open)
+init_open_stateid(struct nfs4_file *fp, struct nfsd4_open *open)
 {
 
         struct nfs4_openowner *oo = open->op_openowner;
         struct nfs4_ol_stateid *retstp = NULL;
+        struct nfs4_ol_stateid *stp;
+
+        stp = open->op_stp;
+        /* We are moving these outside of the spinlocks to avoid the warnings */
+        mutex_init(&stp->st_mutex);
+        mutex_lock(&stp->st_mutex);
 
         spin_lock(&oo->oo_owner.so_client->cl_lock);
         spin_lock(&fp->fi_lock);
@@ -3493,6 +3498,8 @@ init_open_stateid(struct nfs4_ol_stateid *stp, struct nfs4_file *fp,
         retstp = nfsd4_find_existing_open(fp, open);
         if (retstp)
                 goto out_unlock;
+
+        open->op_stp = NULL;
         atomic_inc(&stp->st_stid.sc_count);
         stp->st_stid.sc_type = NFS4_OPEN_STID;
         INIT_LIST_HEAD(&stp->st_locks);
@@ -3502,14 +3509,19 @@ init_open_stateid(struct nfs4_ol_stateid *stp, struct nfs4_file *fp,
         stp->st_access_bmap = 0;
         stp->st_deny_bmap = 0;
         stp->st_openstp = NULL;
-        init_rwsem(&stp->st_rwsem);
         list_add(&stp->st_perstateowner, &oo->oo_owner.so_stateids);
         list_add(&stp->st_perfile, &fp->fi_stateids);
 
 out_unlock:
         spin_unlock(&fp->fi_lock);
         spin_unlock(&oo->oo_owner.so_client->cl_lock);
-        return retstp;
+        if (retstp) {
+                mutex_lock(&retstp->st_mutex);
+                /* To keep mutex tracking happy */
+                mutex_unlock(&stp->st_mutex);
+                stp = retstp;
+        }
+        return stp;
 }
 
 /*
@@ -4305,7 +4317,6 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf
         struct nfs4_client *cl = open->op_openowner->oo_owner.so_client;
         struct nfs4_file *fp = NULL;
         struct nfs4_ol_stateid *stp = NULL;
-        struct nfs4_ol_stateid *swapstp = NULL;
         struct nfs4_delegation *dp = NULL;
         __be32 status;
 
@@ -4335,32 +4346,28 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf
          */
         if (stp) {
                 /* Stateid was found, this is an OPEN upgrade */
-                down_read(&stp->st_rwsem);
+                mutex_lock(&stp->st_mutex);
                 status = nfs4_upgrade_open(rqstp, fp, current_fh, stp, open);
                 if (status) {
-                        up_read(&stp->st_rwsem);
+                        mutex_unlock(&stp->st_mutex);
                         goto out;
                 }
         } else {
-                stp = open->op_stp;
-                open->op_stp = NULL;
-                swapstp = init_open_stateid(stp, fp, open);
-                if (swapstp) {
-                        nfs4_put_stid(&stp->st_stid);
-                        stp = swapstp;
-                        down_read(&stp->st_rwsem);
+                /* stp is returned locked. */
+                stp = init_open_stateid(fp, open);
+                /* See if we lost the race to some other thread */
+                if (stp->st_access_bmap != 0) {
                         status = nfs4_upgrade_open(rqstp, fp, current_fh,
                                                 stp, open);
                         if (status) {
-                                up_read(&stp->st_rwsem);
+                                mutex_unlock(&stp->st_mutex);
                                 goto out;
                         }
                         goto upgrade_out;
                 }
-                down_read(&stp->st_rwsem);
                 status = nfs4_get_vfs_file(rqstp, fp, current_fh, stp, open);
                 if (status) {
-                        up_read(&stp->st_rwsem);
+                        mutex_unlock(&stp->st_mutex);
                         release_open_stateid(stp);
                         goto out;
                 }
@@ -4372,7 +4379,7 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf
         }
 upgrade_out:
         nfs4_inc_and_copy_stateid(&open->op_stateid, &stp->st_stid);
-        up_read(&stp->st_rwsem);
+        mutex_unlock(&stp->st_mutex);
 
         if (nfsd4_has_session(&resp->cstate)) {
                 if (open->op_deleg_want & NFS4_SHARE_WANT_NO_DELEG) {
@@ -4977,12 +4984,12 @@ static __be32 nfs4_seqid_op_checks(struct nfsd4_compound_state *cstate, stateid_
                  * revoked delegations are kept only for free_stateid.
                  */
                 return nfserr_bad_stateid;
-        down_write(&stp->st_rwsem);
+        mutex_lock(&stp->st_mutex);
         status = check_stateid_generation(stateid, &stp->st_stid.sc_stateid, nfsd4_has_session(cstate));
         if (status == nfs_ok)
                 status = nfs4_check_fh(current_fh, &stp->st_stid);
         if (status != nfs_ok)
-                up_write(&stp->st_rwsem);
+                mutex_unlock(&stp->st_mutex);
         return status;
 }
 
@@ -5030,7 +5037,7 @@ static __be32 nfs4_preprocess_confirmed_seqid_op(struct nfsd4_compound_state *cs
                 return status;
         oo = openowner(stp->st_stateowner);
         if (!(oo->oo_flags & NFS4_OO_CONFIRMED)) {
-                up_write(&stp->st_rwsem);
+                mutex_unlock(&stp->st_mutex);
                 nfs4_put_stid(&stp->st_stid);
                 return nfserr_bad_stateid;
         }
@@ -5062,12 +5069,12 @@ nfsd4_open_confirm(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
         oo = openowner(stp->st_stateowner);
         status = nfserr_bad_stateid;
         if (oo->oo_flags & NFS4_OO_CONFIRMED) {
-                up_write(&stp->st_rwsem);
+                mutex_unlock(&stp->st_mutex);
                 goto put_stateid;
         }
         oo->oo_flags |= NFS4_OO_CONFIRMED;
         nfs4_inc_and_copy_stateid(&oc->oc_resp_stateid, &stp->st_stid);
-        up_write(&stp->st_rwsem);
+        mutex_unlock(&stp->st_mutex);
         dprintk("NFSD: %s: success, seqid=%d stateid=" STATEID_FMT "\n",
                 __func__, oc->oc_seqid, STATEID_VAL(&stp->st_stid.sc_stateid));
 
@@ -5143,7 +5150,7 @@ nfsd4_open_downgrade(struct svc_rqst *rqstp,
         nfs4_inc_and_copy_stateid(&od->od_stateid, &stp->st_stid);
         status = nfs_ok;
 put_stateid:
-        up_write(&stp->st_rwsem);
+        mutex_unlock(&stp->st_mutex);
         nfs4_put_stid(&stp->st_stid);
 out:
         nfsd4_bump_seqid(cstate, status);
@@ -5196,7 +5203,7 @@ nfsd4_close(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
         if (status)
                 goto out; 
         nfs4_inc_and_copy_stateid(&close->cl_stateid, &stp->st_stid);
-        up_write(&stp->st_rwsem);
+        mutex_unlock(&stp->st_mutex);
 
         nfsd4_close_open_stateid(stp);
 
@@ -5422,7 +5429,7 @@ init_lock_stateid(struct nfs4_ol_stateid *stp, struct nfs4_lockowner *lo,
         stp->st_access_bmap = 0;
         stp->st_deny_bmap = open_stp->st_deny_bmap;
         stp->st_openstp = open_stp;
-        init_rwsem(&stp->st_rwsem);
+        mutex_init(&stp->st_mutex);
         list_add(&stp->st_locks, &open_stp->st_locks);
         list_add(&stp->st_perstateowner, &lo->lo_owner.so_stateids);
         spin_lock(&fp->fi_lock);
@@ -5591,7 +5598,7 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
                                         &open_stp, nn);
                 if (status)
                         goto out;
-                up_write(&open_stp->st_rwsem);
+                mutex_unlock(&open_stp->st_mutex);
                 open_sop = openowner(open_stp->st_stateowner);
                 status = nfserr_bad_stateid;
                 if (!same_clid(&open_sop->oo_owner.so_client->cl_clientid,
@@ -5600,7 +5607,7 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
                 status = lookup_or_create_lock_state(cstate, open_stp, lock,
                                                         &lock_stp, &new);
                 if (status == nfs_ok)
-                        down_write(&lock_stp->st_rwsem);
+                        mutex_lock(&lock_stp->st_mutex);
         } else {
                 status = nfs4_preprocess_seqid_op(cstate,
                                        lock->lk_old_lock_seqid,
@@ -5704,7 +5711,7 @@ out:
                     seqid_mutating_err(ntohl(status)))
                         lock_sop->lo_owner.so_seqid++;
 
-                up_write(&lock_stp->st_rwsem);
+                mutex_unlock(&lock_stp->st_mutex);
 
                 /*
                  * If this is a new, never-before-used stateid, and we are
@@ -5874,7 +5881,7 @@ nfsd4_locku(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 fput:
         fput(filp);
 put_stateid:
-        up_write(&stp->st_rwsem);
+        mutex_unlock(&stp->st_mutex);
         nfs4_put_stid(&stp->st_stid);
 out:
         nfsd4_bump_seqid(cstate, status);