1 files changed, 40 insertions, 9 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 8799b8708188..1578d7a2667e 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1173,6 +1173,24 @@ static inline int deny_valid(u32 x)
         return x <= NFS4_SHARE_DENY_BOTH;
 }
 
+/*
+ * We store the NONE, READ, WRITE, and BOTH bits separately in the
+ * st_{access,deny}_bmap field of the stateid, in order to track not
+ * only what share bits are currently in force, but also what
+ * combinations of share bits previous opens have used.  This allows us
+ * to enforce the recommendation of rfc 3530 14.2.19 that the server
+ * return an error if the client attempt to downgrade to a combination
+ * of share bits not explicable by closing some of its previous opens.
+ *
+ * XXX: This enforcement is actually incomplete, since we don't keep
+ * track of access/deny bit combinations; so, e.g., we allow:
+ *
+ *      OPEN allow read, deny write
+ *      OPEN allow both, deny none
+ *      DOWNGRADE allow read, deny none
+ *
+ * which we should reject.
+ */
 static void
 set_access(unsigned int *access, unsigned long bmap) {
         int i;
@@ -1570,6 +1588,10 @@ nfs4_upgrade_open(struct svc_rqst *rqstp, struct svc_fh *cur_fh, struct nfs4_sta
                 int err = get_write_access(inode);
                 if (err)
                         return nfserrno(err);
+                err = mnt_want_write(cur_fh->fh_export->ex_path.mnt);
+                if (err)
+                        return nfserrno(err);
+                file_take_write(filp);
         }
         status = nfsd4_truncate(rqstp, cur_fh, open);
         if (status) {
@@ -1579,8 +1601,8 @@ nfs4_upgrade_open(struct svc_rqst *rqstp, struct svc_fh *cur_fh, struct nfs4_sta
         }
         /* remember the open */
         filp->f_mode |= open->op_share_access;
-        set_bit(open->op_share_access, &stp->st_access_bmap);
-        set_bit(open->op_share_deny, &stp->st_deny_bmap);
+        __set_bit(open->op_share_access, &stp->st_access_bmap);
+        __set_bit(open->op_share_deny, &stp->st_deny_bmap);
 
         return nfs_ok;
 }
@@ -1722,9 +1744,9 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf
                 /* Stateid was not found, this is a new OPEN */
                 int flags = 0;
                 if (open->op_share_access & NFS4_SHARE_ACCESS_READ)
-                        flags |= MAY_READ;
+                        flags |= NFSD_MAY_READ;
                 if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE)
-                        flags |= MAY_WRITE;
+                        flags |= NFSD_MAY_WRITE;
                 status = nfs4_new_open(rqstp, &stp, dp, current_fh, flags);
                 if (status)
                         goto out;
@@ -2610,7 +2632,7 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
                  return nfserr_inval;
 
         if ((status = fh_verify(rqstp, &cstate->current_fh,
-                                S_IFREG, MAY_LOCK))) {
+                                S_IFREG, NFSD_MAY_LOCK))) {
                 dprintk("NFSD: nfsd4_lock: permission denied!\n");
                 return status;
         }
@@ -3249,12 +3271,14 @@ nfs4_state_shutdown(void)
         nfs4_unlock_state();
 }
 
+/*
+ * user_recovery_dirname is protected by the nfsd_mutex since it's only
+ * accessed when nfsd is starting.
+ */
 static void
 nfs4_set_recdir(char *recdir)
 {
-        nfs4_lock_state();
         strcpy(user_recovery_dirname, recdir);
-        nfs4_unlock_state();
 }
 
 /*
@@ -3278,6 +3302,12 @@ nfs4_reset_recoverydir(char *recdir)
         return status;
 }
 
+char *
+nfs4_recoverydir(void)
+{
+        return user_recovery_dirname;
+}
+
 /*
  * Called when leasetime is changed.
  *
@@ -3286,11 +3316,12 @@ nfs4_reset_recoverydir(char *recdir)
  * we start to register any changes in lease time.  If the administrator
  * really wants to change the lease time *now*, they can go ahead and bring
  * nfsd down and then back up again after changing the lease time.
+ *
+ * user_lease_time is protected by nfsd_mutex since it's only really accessed
+ * when nfsd is starting
  */
 void
 nfs4_reset_lease(time_t leasetime)
 {
-        lock_kernel();
         user_lease_time = leasetime;
-        unlock_kernel();
 }