1 files changed, 20 insertions, 33 deletions

diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
index ef805eaa9e01..9f1e76ddda5a 100644
--- a/arch/um/drivers/ubd_kern.c
+++ b/arch/um/drivers/ubd_kern.c
@@ -447,43 +447,31 @@ static int bulk_req_safe_read(
 	return n;
 }
 
-/* Called without dev->lock held, and only in interrupt context. */
-static void ubd_handler(void)
+static void ubd_end_request(struct io_thread_req *io_req)
 {
-	int n;
-	int count;
-
-	while(1){
-		n = bulk_req_safe_read(
-			thread_fd,
-			irq_req_buffer,
-			&irq_remainder,
-			&irq_remainder_size,
-			UBD_REQ_BUFFER_SIZE
-		);
-		if (n < 0) {
-			if(n == -EAGAIN)
-				break;
-			printk(KERN_ERR "spurious interrupt in ubd_handler, "
-			       "err = %d\n", -n);
-			return;
-		}
-		for (count = 0; count < n/sizeof(struct io_thread_req *); count++) {
-			struct io_thread_req *io_req = (*irq_req_buffer)[count];
-
-			if ((io_req->error == BLK_STS_NOTSUPP) && (req_op(io_req->req) == REQ_OP_DISCARD)) {
-				blk_queue_max_discard_sectors(io_req->req->q, 0);
-				blk_queue_max_write_zeroes_sectors(io_req->req->q, 0);
-			}
-			blk_mq_end_request(io_req->req, io_req->error);
-			kfree(io_req);
-		}
+	if (io_req->error == BLK_STS_NOTSUPP) {
+		if (req_op(io_req->req) == REQ_OP_DISCARD)
+			blk_queue_disable_discard(io_req->req->q);
+		else if (req_op(io_req->req) == REQ_OP_WRITE_ZEROES)
+			blk_queue_disable_write_zeroes(io_req->req->q);
 	}
+	blk_mq_end_request(io_req->req, io_req->error);
+	kfree(io_req);
 }
 
 static irqreturn_t ubd_intr(int irq, void *dev)
 {
-	ubd_handler();
+	int len, i;
+
+	while ((len = bulk_req_safe_read(thread_fd, irq_req_buffer,
+			&irq_remainder, &irq_remainder_size,
+			UBD_REQ_BUFFER_SIZE)) >= 0) {
+		for (i = 0; i < len / sizeof(struct io_thread_req *); i++)
+			ubd_end_request((*irq_req_buffer)[i]);
+	}
+
+	if (len < 0 && len != -EAGAIN)
+		pr_err("spurious interrupt in %s, err = %d\n", __func__, len);
 	return IRQ_HANDLED;
 }
 
@@ -847,6 +835,7 @@ static int ubd_add(int n, char **error_out)
 	struct queue_limits lim = {
 		.max_segments		= MAX_SG,
 		.seg_boundary_mask	= PAGE_SIZE - 1,
+		.features		= BLK_FEAT_WRITE_CACHE,
 	};
 	struct gendisk *disk;
 	int err = 0;
@@ -893,8 +882,6 @@ static int ubd_add(int n, char **error_out)
 		goto out_cleanup_tags;
 	}
 
-	blk_queue_flag_set(QUEUE_FLAG_NONROT, disk->queue);
-	blk_queue_write_cache(disk->queue, true, false);
 	disk->major = UBD_MAJOR;
 	disk->first_minor = n << UBD_SHIFT;
 	disk->minors = 1 << UBD_SHIFT;