--- block_dev.c.orig	Mon Mar 13 17:57:27 2000
+++ block_dev.c	Tue Mar 14 15:43:06 2000
@@ -14,7 +14,7 @@
 extern int *blksize_size[];
 
 #define MAX_BUF_PER_PAGE (PAGE_SIZE / 512)
-#define NBUF 64
+#define NBUF 512
 
 ssize_t block_write(struct file * filp, const char * buf,
 		    size_t count, loff_t *ppos)
@@ -194,8 +194,12 @@
 	rblocks = blocks = (left + offset + blocksize - 1) >> blocksize_bits;
 	bhb = bhe = buflist;
 	if (filp->f_reada) {
-	        if (blocks < read_ahead[MAJOR(dev)] / (blocksize >> 9))
-			blocks = read_ahead[MAJOR(dev)] / (blocksize >> 9);
+		blocks += read_ahead[MAJOR(dev)] / (blocksize >> 9);
+		if (block + blocks > size) {
+			blocks = size - block;
+			if (blocks == 0)
+				return 0;
+		}
 		if (rblocks > blocks)
 			blocks = rblocks;