diff -ur v2.4.7/drivers/block/ll_rw_blk.c vm-2.4.7/drivers/block/ll_rw_blk.c
--- v2.4.7/drivers/block/ll_rw_blk.c	Sun Jul 22 19:17:15 2001
+++ vm-2.4.7/drivers/block/ll_rw_blk.c	Fri Aug  3 20:03:39 2001
@@ -122,14 +122,14 @@
  * queued sectors for all devices, used to make sure we don't fill all
  * of memory with locked buffers
  */
+DECLARE_WAIT_QUEUE_HEAD(blk_buffers_wait);
 atomic_t queued_sectors;
 
 /*
  * high and low watermark for above
  */
-static int high_queued_sectors, low_queued_sectors;
+int high_queued_sectors, low_queued_sectors;
 static int batch_requests, queue_nr_requests;
-static DECLARE_WAIT_QUEUE_HEAD(blk_buffers_wait);
 
 static inline int get_max_sectors(kdev_t dev)
 {
diff -ur v2.4.7/include/linux/blkdev.h vm-2.4.7/include/linux/blkdev.h
--- v2.4.7/include/linux/blkdev.h	Fri Aug  3 16:07:23 2001
+++ vm-2.4.7/include/linux/blkdev.h	Fri Aug  3 20:04:07 2001
@@ -176,7 +176,9 @@
 
 extern int * max_segments[MAX_BLKDEV];
 
+extern wait_queue_head_t blk_buffers_wait;
 extern atomic_t queued_sectors;
+extern int low_queued_sectors;
 
 #define MAX_SEGMENTS 128
 #define MAX_SECTORS 255
@@ -205,12 +207,15 @@
 		return 512;
 }
 
-#define blk_finished_io(nsects)				\
+#define blk_finished_io(nsects) do {			\
 	atomic_sub(nsects, &queued_sectors);		\
 	if (atomic_read(&queued_sectors) < 0) {		\
 		printk("block: queued_sectors < 0\n");	\
 		atomic_set(&queued_sectors, 0);		\
-	}
+	}						\
+	if (atomic_read(&queued_sectors) < low_queued_sectors) \
+		wake_up(&blk_buffers_wait);		\
+} while (0)
 
 #define blk_started_io(nsects)				\
 	atomic_add(nsects, &queued_sectors);