Index: sys/kern/vfs_bio.c
===================================================================
--- sys/kern/vfs_bio.c
+++ sys/kern/vfs_bio.c
@@ -3887,8 +3887,9 @@
 		 */
 		lockflags = LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK;
 
-		if (flags & GB_LOCK_NOWAIT)
+		if ((flags & GB_LOCK_NOWAIT) != 0)
 			lockflags |= LK_NOWAIT;
+		bp->b_flags &= ~B_HOLE;
 
 		error = BUF_TIMELOCK(bp, lockflags,
 		    BO_LOCKPTR(bo), "getblk", slpflag, slptimeo);
@@ -4006,10 +4007,10 @@
 		 * here.
 		 */
 		if (flags & GB_NOCREAT)
-			return NULL;
+			return (NULL);
 		if (bdomain[bo->bo_domain].bd_freebuffers == 0 &&
 		    TD_IS_IDLETHREAD(curthread))
-			return NULL;
+			return (NULL);
 
 		bsize = vn_isdisk(vp, NULL) ? DEV_BSIZE : bo->bo_bsize;
 		KASSERT(bsize != 0, ("bsize == 0, check bo->bo_bsize"));
@@ -4027,7 +4028,7 @@
 		bp = getnewbuf(vp, slpflag, slptimeo, maxsize, flags);
 		if (bp == NULL) {
 			if (slpflag || slptimeo)
-				return NULL;
+				return (NULL);
 			/*
 			 * XXX This is here until the sleep path is diagnosed
 			 * enough to work under very low memory conditions.
@@ -4101,6 +4102,10 @@
 		allocbuf(bp, size);
 		bufspace_release(bufdomain(bp), maxsize);
 		bp->b_flags &= ~B_DONE;
+		if (flags & GB_HOLE)
+			bp->b_flags |= B_HOLE;
+		else
+			bp->b_flags &= ~B_HOLE;
 	}
 	CTR4(KTR_BUF, "getblk(%p, %ld, %d) = %p", vp, (long)blkno, size, bp);
 	BUF_ASSERT_HELD(bp);
@@ -4435,6 +4440,7 @@
 		KASSERT(buf_mapped(bp), ("bufdone: bp %p not mapped", bp));
 		(*bp->b_ckhashcalc)(bp);
 	}
+	bp->b_flags &= ~B_HOLE;
 	/*
 	 * For asynchronous completions, release the buffer now. The brelse
 	 * will do a wakeup there if necessary - so no need to do a wakeup
Index: sys/sys/buf.h
===================================================================
--- sys/sys/buf.h
+++ sys/sys/buf.h
@@ -225,7 +225,7 @@
 #define	B_NOCACHE	0x00008000	/* Do not cache block after use. */
 #define	B_MALLOC	0x00010000	/* malloced b_data */
 #define	B_CLUSTEROK	0x00020000	/* Pagein op, so swap() can count it. */
-#define	B_00040000	0x00040000	/* Available flag. */
+#define	B_HOLE		0x00040000	/* Do not instantiate hole. */
 #define	B_00080000	0x00080000	/* Available flag. */
 #define	B_00100000	0x00100000	/* Available flag. */
 #define	B_00200000	0x00200000	/* Available flag. */
@@ -479,6 +479,7 @@
 #define	GB_UNMAPPED	0x0008		/* Do not mmap buffer pages. */
 #define	GB_KVAALLOC	0x0010		/* But allocate KVA. */
 #define	GB_CKHASH	0x0020		/* If reading, calc checksum hash */
+#define	GB_HOLE		0x0040		/* Do not instantiate holes */
 
 #ifdef _KERNEL
 extern int	nbuf;			/* The number of buffer headers */
Index: sys/ufs/ffs/ffs_vnops.c
===================================================================
--- sys/ufs/ffs/ffs_vnops.c
+++ sys/ufs/ffs/ffs_vnops.c
@@ -462,6 +462,25 @@
 #endif
 }
 
+static int
+ffs_read_hole(struct uio *uio, long xfersize, long *size)
+{
+	ssize_t saved_resid, tlen;
+	int error;
+
+	while (xfersize > 0) {
+		tlen = min(xfersize, ZERO_REGION_SIZE);
+		saved_resid = uio->uio_resid;
+		error = uiomove(__DECONST(void *, zero_region), tlen, uio);
+		if (error != 0)
+			return (error);
+		tlen = saved_resid - uio->uio_resid;
+		xfersize -= tlen;
+		*size -= tlen;
+	}
+	return (0);
+}
+
 /*
  * Vnode op for reading.
  */
@@ -566,7 +585,7 @@
 			 * Don't do readahead if this is the end of the file.
 			 */
 			error = bread_gb(vp, lbn, size, NOCRED,
-			    GB_UNMAPPED, &bp);
+			    GB_UNMAPPED | GB_HOLE, &bp);
 		} else if ((vp->v_mount->mnt_flag & MNT_NOCLUSTERR) == 0) {
 			/*
 			 * Otherwise if we are allowed to cluster,
@@ -577,7 +596,7 @@
 			 */
 			error = cluster_read(vp, ip->i_size, lbn,
 			    size, NOCRED, blkoffset + uio->uio_resid,
-			    seqcount, GB_UNMAPPED, &bp);
+			    seqcount, GB_UNMAPPED | GB_HOLE, &bp);
 		} else if (seqcount > 1) {
 			/*
 			 * If we are NOT allowed to cluster, then
@@ -589,7 +608,8 @@
 			 */
 			u_int nextsize = blksize(fs, ip, nextlbn);
 			error = breadn_flags(vp, lbn, size, &nextlbn,
-			    &nextsize, 1, NOCRED, GB_UNMAPPED, NULL, &bp);
+			    &nextsize, 1, NOCRED, GB_UNMAPPED | GB_HOLE,
+			    NULL, &bp);
 		} else {
 			/*
 			 * Failing all of the above, just read what the
@@ -597,9 +617,14 @@
 			 * the first option above.
 			 */
 			error = bread_gb(vp, lbn, size, NOCRED,
-			    GB_UNMAPPED, &bp);
+			    GB_UNMAPPED | GB_HOLE, &bp);
 		}
-		if (error) {
+		if (error == EJUSTRETURN) {
+			error = ffs_read_hole(uio, xfersize, &size);
+			if (error == 0)
+				continue;
+		}
+		if (error != 0) {
 			brelse(bp);
 			bp = NULL;
 			break;
Index: sys/ufs/ufs/ufs_vnops.c
===================================================================
--- sys/ufs/ufs/ufs_vnops.c
+++ sys/ufs/ufs/ufs_vnops.c
@@ -2334,10 +2334,14 @@
 			bufdone(bp);
 			return (0);
 		}
-		if ((long)bp->b_blkno == -1)
+		if ((long)bp->b_blkno == -1 && (bp->b_flags & B_HOLE) == 0)
 			vfs_bio_clrbuf(bp);
 	}
 	if ((long)bp->b_blkno == -1) {
+		if ((bp->b_flags & B_HOLE) != 0) {
+			bp->b_error = EJUSTRETURN;
+			bp->b_ioflags |= BIO_ERROR;
+		}
 		bufdone(bp);
 		return (0);
 	}