[v2] dm: Fix alignment stacking on partitioned devices

Commit Message

Martin K. Petersen Jan. 6, 2010, 8:39 a.m. UTC

None

Patch

diff --git a/block/blk-settings.c b/block/blk-settings.c
index d52d4ad..4b43e14 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -631,6 +631,27 @@  int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
 EXPORT_SYMBOL(blk_stack_limits);
 
 /**
+ * bdev_stack_limits - adjust queue limits for stacked drivers
+ * @t:	the stacking driver limits (top device)
+ * @bdev:  the component block_device (bottom)
+ * @start:  first data sector within component device
+ *
+ * Description:
+ *    Merges queue limits for a top device and a block_device.  Returns
+ *    0 if alignment didn't change.  Returns -1 if adding the bottom
+ *    device caused misalignment.
+ */
+int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
+		      sector_t start)
+{
+	struct request_queue *bq = bdev_get_queue(bdev);
+
+	start += get_start_sect(bdev);
+
+	return blk_stack_limits(t, &bq->limits, start << 9);
+}
+
+/**
  * disk_stack_limits - adjust queue limits for stacked drivers
  * @disk:  MD/DM gendisk (top)
  * @bdev:  the underlying block device (bottom)
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index be62547..e0866a0 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -503,7 +503,7 @@  int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
 		return 0;
 	}
 
-	if (blk_stack_limits(limits, &q->limits, start << 9) < 0)
+	if (bdev_stack_limits(limits, bdev, start) < 0)
 		DMWARN("%s: target device %s is misaligned: "
 		       "physical_block_size=%u, logical_block_size=%u, "
 		       "alignment_offset=%u, start=%llu",
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 9b98173..70b7ede 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -938,6 +938,8 @@  extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
 extern void blk_set_default_limits(struct queue_limits *lim);
 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
 			    sector_t offset);
+extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
+			    sector_t offset);
 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
 			      sector_t offset);
 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);