Make NFSv4 'setattr()' method use the cached stateid if the file is

already open.

fs/nfs/nfs4proc.c

@@ -461,18 +461,6 @@ nfs4_setup_savefh(struct nfs4_compound *cp)
         cp->req_nops++;
 }
 
-static void
-nfs4_setup_setattr(struct nfs4_compound *cp, char *stateid, struct iattr *iap)
-{
-	struct nfs4_setattr *setattr = GET_OP(cp, setattr);
-
-	setattr->st_stateid = stateid;
-	setattr->st_iap = iap;
-	
-	OPNUM(cp) = OP_SETATTR;
-	cp->req_nops++;
-}
-
 static void
 nfs4_setup_setclientid(struct nfs4_compound *cp, u32 program, unsigned short port)
 {
@@ -681,20 +669,39 @@ nfs4_do_open(struct inode *dir, struct qstr *name, int flags,
 	return status;
 }
 
-static int
-do_setattr(struct nfs_server *server, struct nfs_fattr *fattr,
-	   struct nfs_fh *fhandle, struct iattr *sattr, char *stateid)
-{
-	struct nfs4_compound	compound;
-	struct nfs4_op		ops[3];
-	u32			bmres[2];
-
-	fattr->valid = 0;
-	nfs4_setup_compound(&compound, ops, server, "setattr");
-	nfs4_setup_putfh(&compound, fhandle);
-	nfs4_setup_setattr(&compound, stateid, sattr);
-	nfs4_setup_getattr(&compound, fattr, bmres);
-	return nfs4_call_compound(&compound, NULL, 0);
+int
+nfs4_do_setattr(struct nfs_server *server, struct nfs_fattr *fattr,
+                struct nfs_fh *fhandle, struct iattr *sattr,
+                struct nfs4_shareowner *sp)
+{
+        u32                     g_bmres[2];
+        struct nfs4_getattr     getattr = {
+                .gt_bmval       = nfs4_fattr_bitmap,
+                .gt_attrs       = fattr,
+                .gt_bmres       = g_bmres,
+        };
+        struct nfs_setattrargs  arg = {
+                .fh             = fhandle,
+                .iap            = sattr,
+                .attr           = &getattr,
+        };
+        struct nfs_setattrres  res = {
+                .attr           = &getattr,
+        };
+        struct rpc_message msg = {
+                .rpc_proc       = &nfs4_procedures[NFSPROC4_CLNT_SETATTR],
+                .rpc_argp       = &arg,
+                .rpc_resp       = &res,
+        };
+
+        fattr->valid = 0;
+
+        if (sp)
+                memcpy(arg.stateid, sp->so_stateid, sizeof(nfs4_stateid));
+        else
+                memcpy(arg.stateid, zero_stateid, sizeof(nfs4_stateid));
+
+        return(rpc_call_sync(server->client, &msg, 0));
 }
 
 /* 
@@ -839,7 +846,18 @@ nfs4_proc_getattr(struct inode *inode, struct nfs_fattr *fattr)
  * The file is not closed if it is opened due to the a request to change
  * the size of the file. The open call will not be needed once the
  * VFS layer lookup-intents are implemented.
+ *
  * Close is called when the inode is destroyed.
+ * If we haven't opened the file for O_WRONLY, we
+ * need to in the size_change case to obtain a stateid.
+ *
+ * Got race?
+ * Because OPEN is always done by name in nfsv4, it is
+ * possible that we opened a different file by the same
+ * name.  We can recognize this race condition, but we
+ * can't do anything about it besides returning an error.
+ *
+ * This will be fixed with VFS changes (lookup-intent).
  */
 static int
 nfs4_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr,
@@ -847,37 +865,31 @@ nfs4_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr,
 {
 	struct inode *		inode = dentry->d_inode;
 	int			size_change = sattr->ia_valid & ATTR_SIZE;
-	struct nfs_fh		throwaway_fh;
 	struct nfs4_shareowner	*sp = NULL;
-	int			status, fake = 1;
+	int			status;
 
 	fattr->valid = 0;
 	
 	if (size_change) {
+		if (NFS_I(inode)->wo_owner) {
+			/* file is already open for O_WRONLY */
+			sp = NFS_I(inode)->wo_owner;
+			goto no_open;
+		}
 		status = nfs4_do_open(dentry->d_parent->d_inode, 
-				&dentry->d_name,
-				O_WRONLY, NULL, fattr,
-				&throwaway_fh,&sp);
+				&dentry->d_name, O_WRONLY, NULL, fattr,
+				NULL, &sp);
 		if (status)
 			return status;
-		fake = 0;
-		/*
-		 * Because OPEN is always done by name in nfsv4, it is
-		 * possible that we opened a different file by the same
-		 * name.  We can recognize this race condition, but we
-		 * can't do anything about it besides returning an error.
-		 *
-		 * XXX: Should we compare filehandles too, as in
-		 * nfs_find_actor()?
-		 */
+
 		if (fattr->fileid != NFS_FILEID(inode)) {
 			printk(KERN_WARNING "nfs: raced in setattr, returning -EIO\n");
 			return -EIO;
 		}
 	}
-	
-	status = do_setattr(NFS_SERVER(inode), fattr, NFS_FH(inode), sattr, 
-	                    fake == 1? zero_stateid: sp->so_stateid);
+no_open:
+	status = nfs4_do_setattr(NFS_SERVER(inode), fattr,
+			NFS_FH(inode), sattr, sp);
 	return status;
 }
 
@@ -1097,8 +1109,8 @@ nfs4_proc_create(struct inode *dir, struct qstr *name, struct iattr *sattr,
 	status = nfs4_do_open(dir, name, oflags, sattr, fattr, fhandle, &sp);
 	if (!status) {
 		if (flags & O_EXCL) {
-			status = do_setattr(NFS_SERVER(dir), fattr,
-			                     fhandle, sattr, sp->so_stateid);
+			status = nfs4_do_setattr(NFS_SERVER(dir), fattr,
+			                     fhandle, sattr, sp);
 		/* XXX should i bother closing the file? */
 		}
 	}

fs/nfs/nfs4xdr.c

@@ -150,8 +150,14 @@ extern int			nfs_stat_to_errno(int);
 #define NFS4_dec_close_sz       compound_decode_hdr_maxsz + \
                                 decode_putfh_maxsz + \
                                 op_decode_hdr_maxsz + 4
-
-
+#define NFS4_enc_setattr_sz     compound_encode_hdr_maxsz + \
+                                encode_putfh_maxsz + \
+                                op_encode_hdr_maxsz + 4 + \
+                                nfs4_fattr_bitmap_maxsz + \
+                                encode_getattr_maxsz
+#define NFS4_dec_setattr_sz     compound_decode_hdr_maxsz + \
+                                decode_putfh_maxsz + \
+                                op_decode_hdr_maxsz + 3
 
 
 static struct {
@@ -771,16 +777,16 @@ encode_savefh(struct xdr_stream *xdr)
 }
 
 static int
-encode_setattr(struct xdr_stream *xdr, struct nfs4_setattr *setattr)
+encode_setattr(struct xdr_stream *xdr, struct nfs_setattrargs *arg)
 {
 	int status;
 	uint32_t *p;
 	
         RESERVE_SPACE(4+sizeof(nfs4_stateid));
         WRITE32(OP_SETATTR);
-	WRITEMEM(setattr->st_stateid, sizeof(nfs4_stateid));
+	WRITEMEM(arg->stateid, sizeof(nfs4_stateid));
 
-        if ((status = encode_attrs(xdr, setattr->st_iap)))
+        if ((status = encode_attrs(xdr, arg->iap)))
 		return status;
 
         return 0;
@@ -907,9 +913,6 @@ encode_compound(struct xdr_stream *xdr, struct nfs4_compound *cp, struct rpc_rqs
 		case OP_SAVEFH:
 			status = encode_savefh(xdr);
 			break;
-		case OP_SETATTR:
-			status = encode_setattr(xdr, &cp->ops[i].u.setattr);
-			break;
 		case OP_SETCLIENTID:
 			status = encode_setclientid(xdr, &cp->ops[i].u.setclientid);
 			break;
@@ -1061,6 +1064,31 @@ nfs4_xdr_enc_read(struct rpc_rqst *req, uint32_t *p, struct nfs_readargs *args)
 	return status;
 }
 
+/*
+ * Encode an SETATTR request
+ */
+static int
+nfs4_xdr_enc_setattr(struct rpc_rqst *req, uint32_t *p, struct nfs_setattrargs *args)
+{
+        struct xdr_stream xdr;
+        struct compound_hdr hdr = {
+                .nops   = 3,
+        };
+        int status;
+
+        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
+        encode_compound_hdr(&xdr, &hdr);
+        status = encode_putfh(&xdr, args->fh);
+        if(status)
+                goto out;
+        status = encode_setattr(&xdr, args);
+        if(status)
+                goto out;
+        status = encode_getattr(&xdr, args->attr);
+out:
+        return status;
+}
+
 /*
  * Encode a WRITE request
  */
@@ -1991,7 +2019,7 @@ decode_savefh(struct xdr_stream *xdr)
 }
 
 static int
-decode_setattr(struct xdr_stream *xdr)
+decode_setattr(struct xdr_stream *xdr, struct nfs_setattrres *res)
 {
 	uint32_t *p;
 	uint32_t bmlen;
@@ -2144,9 +2172,6 @@ decode_compound(struct xdr_stream *xdr, struct nfs4_compound *cp, struct rpc_rqs
 		case OP_SAVEFH:
 			status = decode_savefh(xdr);
 			break;
-		case OP_SETATTR:
-			status = decode_setattr(xdr);
-			break;
 		case OP_SETCLIENTID:
 			status = decode_setclientid(xdr, &op->u.setclientid);
 			break;
@@ -2274,6 +2299,31 @@ nfs4_xdr_dec_open_confirm(struct rpc_rqst *rqstp, uint32_t *p, struct nfs_open_c
         return status;
 }
 
+/*
+ * Decode SETATTR response
+ */
+static int
+nfs4_xdr_dec_setattr(struct rpc_rqst *rqstp, uint32_t *p, struct nfs_setattrres *res)
+{
+        struct xdr_stream xdr;
+        struct compound_hdr hdr;
+        int status;
+
+        xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
+        status = decode_compound_hdr(&xdr, &hdr);
+        if (status)
+                goto out;
+        status = decode_putfh(&xdr);
+        if (status)
+                goto out;
+        status = decode_setattr(&xdr, res);
+        if (status)
+                goto out;
+        status = decode_getattr(&xdr, res->attr);
+out:
+        return status;
+}
+
 
 /*
  * Decode Read response
@@ -2418,7 +2468,8 @@ struct rpc_procinfo	nfs4_procedures[] = {
   PROC(COMMIT,		enc_commit,	dec_commit),
   PROC(OPEN,		enc_open,	dec_open),
   PROC(OPEN_CONFIRM,	enc_open_confirm,	dec_open_confirm),
-  PROC(CLOSE,	enc_close,	dec_close),
+  PROC(CLOSE,		enc_close,	dec_close),
+  PROC(SETATTR,		enc_setattr,	dec_setattr),
 };
 
 struct rpc_version		nfs_version4 = {

include/linux/nfs4.h

@@ -209,6 +209,7 @@ enum {
 	NFSPROC4_CLNT_OPEN,
 	NFSPROC4_CLNT_OPEN_CONFIRM,
 	NFSPROC4_CLNT_CLOSE,
+	NFSPROC4_CLNT_SETATTR,
 };
 
 #endif

include/linux/nfs_xdr.h

@@ -241,6 +241,17 @@ struct nfs_renameargs {
 	unsigned int		tolen;
 };
 
+struct nfs_setattrargs {
+	struct nfs_fh *                 fh;
+	nfs4_stateid                    stateid;
+	struct iattr *                  iap;
+	struct nfs4_getattr *           attr;
+};
+
+struct nfs_setattrres {
+	struct nfs4_getattr *           attr;
+};
+
 struct nfs_linkargs {
 	struct nfs_fh *		fromfh;
 	struct nfs_fh *		tofh;