[PATCH] dm: fix block device resizing

From: Joe Thornber <thornber@sistina.com>

When setting the size of a Device-Mapper device in the gendisk entry, also
try to set the size of the corresponding block_device entry's inode.  This is
necessary to allow online device/filesystem resizing to work correctly.
[Kevin Corry]

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 76cd0ed507884ca5dcb0b49254df19a29d885d04..c116277d664cc73adc148ec743afe0d66b89752e 100644 (file)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -666,6 +666,20 @@ static void event_callback(void *context)
        up_write(&md->lock);
 }
 
+static void __set_size(struct gendisk *disk, sector_t size)
+{
+       struct block_device *bdev;
+
+       set_capacity(disk, size);
+       bdev = bdget_disk(disk, 0);
+       if (bdev) {
+               down(&bdev->bd_inode->i_sem);
+               i_size_write(bdev->bd_inode, size << SECTOR_SHIFT);
+               up(&bdev->bd_inode->i_sem);
+               bdput(bdev);
+       }
+}
+
 static int __bind(struct mapped_device *md, struct dm_table *t)
 {
        request_queue_t *q = md->queue;
@@ -673,7 +687,7 @@ static int __bind(struct mapped_device *md, struct dm_table *t)
        md->map = t;
 
        size = dm_table_get_size(t);
-       set_capacity(md->disk, size);
+       __set_size(md->disk, size);
        if (size == 0)
                return 0;
 
@@ -692,7 +706,6 @@ static void __unbind(struct mapped_device *md)
        dm_table_event_callback(md->map, NULL, NULL);
        dm_table_put(md->map);
        md->map = NULL;
-       set_capacity(md->disk, 0);
 }
 
 /*