# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher.
# This patch includes the following deltas:
#	           ChangeSet	1.566   -> 1.567  
#	drivers/block/ll_rw_blk.c	1.102   -> 1.103  
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 02/09/18	axboe@burns.home.kernel.dk	1.567
# impose sane limits on queue restrictions. that means:
# 
# o q->max_sectors must be able to at least span a page
# o q->max_phys_segments and q->max_hw_segments must be at least 1
# o q->max_segment_size must be at least page sized
# o q->seg_boundary_mask must be at least PAGE_CACHE_SIZE-1
# --------------------------------------------
#
diff -Nru a/drivers/block/ll_rw_blk.c b/drivers/block/ll_rw_blk.c
--- a/drivers/block/ll_rw_blk.c	Wed Sep 18 13:29:04 2002
+++ b/drivers/block/ll_rw_blk.c	Wed Sep 18 13:29:04 2002
@@ -204,6 +204,11 @@
  **/
 void blk_queue_max_sectors(request_queue_t *q, unsigned short max_sectors)
 {
+	if ((max_sectors << 9) < PAGE_CACHE_SIZE) {
+		max_sectors = 1 << (PAGE_CACHE_SHIFT - 9);
+		printk("%s: set to minimum %d\n", __FUNCTION__, max_sectors);
+	}
+
 	q->max_sectors = max_sectors;
 }
 
@@ -219,6 +224,11 @@
  **/
 void blk_queue_max_phys_segments(request_queue_t *q, unsigned short max_segments)
 {
+	if (!max_segments) {
+		max_segments = 1;
+		printk("%s: set to minimum %d\n", __FUNCTION__, max_segments);
+	}
+
 	q->max_phys_segments = max_segments;
 }
 
@@ -235,6 +245,11 @@
  **/
 void blk_queue_max_hw_segments(request_queue_t *q, unsigned short max_segments)
 {
+	if (!max_segments) {
+		max_segments = 1;
+		printk("%s: set to minimum %d\n", __FUNCTION__, max_segments);
+	}
+
 	q->max_hw_segments = max_segments;
 }
 
@@ -249,6 +264,11 @@
  **/
 void blk_queue_max_segment_size(request_queue_t *q, unsigned int max_size)
 {
+	if (max_size < PAGE_CACHE_SIZE) {
+		max_size = PAGE_CACHE_SIZE;
+		printk("%s: set to minimum %d\n", __FUNCTION__, max_size);
+	}
+
 	q->max_segment_size = max_size;
 }
 
@@ -275,6 +295,11 @@
  **/
 void blk_queue_segment_boundary(request_queue_t *q, unsigned long mask)
 {
+	if (mask < PAGE_CACHE_SIZE - 1) {
+		mask = PAGE_CACHE_SIZE - 1;
+		printk("%s: set to minimum %lx\n", __FUNCTION__, mask);
+	}
+
 	q->seg_boundary_mask = mask;
 }