nfsclient: eliminate ncl_writebp()

Use plain bufwrite() instead.  ncl_writebp() evolved to mostly repeat
bufwrite() code with some ommisions, most notably runningbufspace
accounting.

Reviewed by:	imp, markj, rmacklem
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D43249

sys/fs/nfsclient/nfs.h

@@ -111,7 +111,6 @@ int ncl_readdirrpc(struct vnode *, struct uio *, struct ucred *,
     struct thread *);
 int ncl_readdirplusrpc(struct vnode *, struct uio *, struct ucred *,
     struct thread *);
-int ncl_writebp(struct buf *, int, struct thread *);
 int ncl_commit(struct vnode *, u_quad_t, int, struct ucred *, struct thread *);
 void ncl_clearcommit(struct mount *);
 int ncl_fsinfo(struct nfsmount *, struct vnode *, struct ucred *,

sys/fs/nfsclient/nfs_clbio.c

@@ -1312,7 +1312,7 @@ ncl_write(struct vop_write_args *ap)
 			}
 		} else if ((n + on) == biosize || (ioflag & IO_ASYNC) != 0) {
 			bp->b_flags |= B_ASYNC;
-			(void) ncl_writebp(bp, 0, NULL);
+			(void) bwrite(bp);
 		} else {
 			bdwrite(bp);
 		}

sys/fs/nfsclient/nfs_clnode.c

@@ -58,7 +58,6 @@
 #include <nfs/nfs_lock.h>
 
 extern struct vop_vector newnfs_vnodeops;
-extern struct buf_ops buf_ops_newnfs;
 MALLOC_DECLARE(M_NEWNFSREQ);
 
 uma_zone_t newnfsnode_zone;
@@ -130,7 +129,6 @@ ncl_nget(struct mount *mntp, u_int8_t *fhp, int fhsize, struct nfsnode **npp,
 	}
 	vp = nvp;
 	KASSERT(vp->v_bufobj.bo_bsize != 0, ("ncl_nget: bo_bsize == 0"));
-	vp->v_bufobj.bo_ops = &buf_ops_newnfs;
 	vp->v_data = np;
 	np->n_vnode = vp;
 	/* 

sys/fs/nfsclient/nfs_clport.c

@@ -77,7 +77,6 @@ extern u_int32_t newnfs_true, newnfs_false, newnfs_xdrneg1;
 extern struct vop_vector newnfs_vnodeops;
 extern struct vop_vector newnfs_fifoops;
 extern uma_zone_t newnfsnode_zone;
-extern struct buf_ops buf_ops_newnfs;
 extern uma_zone_t ncl_pbuf_zone;
 extern short nfsv4_cbport;
 extern int nfscl_enablecallb;
@@ -235,7 +234,6 @@ nfscl_nget(struct mount *mntp, struct vnode *dvp, struct nfsfh *nfhp,
 	}
 	vp = nvp;
 	KASSERT(vp->v_bufobj.bo_bsize != 0, ("nfscl_nget: bo_bsize == 0"));
-	vp->v_bufobj.bo_ops = &buf_ops_newnfs;
 	vp->v_data = np;
 	np->n_vnode = vp;
 	/* 

sys/fs/nfsclient/nfs_clvnops.c

@@ -2925,7 +2925,7 @@ ncl_flush(struct vnode *vp, int waitfor, struct thread *td,
 	 * A b_flags == (B_DELWRI | B_NEEDCOMMIT) block has been written to the
 	 * server, but has not been committed to stable storage on the server
 	 * yet. On the first pass, the byte range is worked out and the commit
-	 * rpc is done. On the second pass, ncl_writebp() is called to do the
+	 * rpc is done. On the second pass, bwrite() is called to do the
 	 * job.
 	 */
 again:
@@ -3438,54 +3438,6 @@ nfs_print(struct vop_print_args *ap)
 	return (0);
 }
 
-/*
- * This is the "real" nfs::bwrite(struct buf*).
- * We set B_CACHE if this is a VMIO buffer.
- */
-int
-ncl_writebp(struct buf *bp, int force __unused, struct thread *td)
-{
-	int oldflags, rtval;
-
-	if (bp->b_flags & B_INVAL) {
-		brelse(bp);
-		return (0);
-	}
-
-	oldflags = bp->b_flags;
-	bp->b_flags |= B_CACHE;
-
-	/*
-	 * Undirty the bp.  We will redirty it later if the I/O fails.
-	 */
-	bundirty(bp);
-	bp->b_flags &= ~B_DONE;
-	bp->b_ioflags &= ~BIO_ERROR;
-	bp->b_iocmd = BIO_WRITE;
-
-	bufobj_wref(bp->b_bufobj);
-	curthread->td_ru.ru_oublock++;
-
-	/*
-	 * Note: to avoid loopback deadlocks, we do not
-	 * assign b_runningbufspace.
-	 */
-	vfs_busy_pages(bp, 1);
-
-	BUF_KERNPROC(bp);
-	bp->b_iooffset = dbtob(bp->b_blkno);
-	bstrategy(bp);
-
-	if ((oldflags & B_ASYNC) != 0)
-		return (0);
-
-	rtval = bufwait(bp);
-	if (oldflags & B_DELWRI)
-		reassignbuf(bp);
-	brelse(bp);
-	return (rtval);
-}
-
 /*
  * nfs special file access vnode op.
  * Essentially just get vattr and then imitate iaccess() since the device is
@@ -3602,26 +3554,6 @@ nfsfifo_close(struct vop_close_args *ap)
 	return (fifo_specops.vop_close(ap));
 }
 
-/*
- * Just call ncl_writebp() with the force argument set to 1.
- *
- * NOTE: B_DONE may or may not be set in a_bp on call.
- */
-static int
-nfs_bwrite(struct buf *bp)
-{
-
-	return (ncl_writebp(bp, 1, curthread));
-}
-
-struct buf_ops buf_ops_newnfs = {
-	.bop_name	=	"buf_ops_nfs",
-	.bop_write	=	nfs_bwrite,
-	.bop_strategy	=	bufstrategy,
-	.bop_sync	=	bufsync,
-	.bop_bdflush	=	bufbdflush,
-};
-
 static int
 nfs_getacl(struct vop_getacl_args *ap)
 {