rbd: only set disk to read-only once

rbd_open(), called every time the device is opened, calls
set_device_ro().  There's no reason to set the device read-only or
read-write every time it is opened. Just do this once during device
setup, using set_disk_ro() instead because the struct block_device
isn't available to us there.

Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
Reviewed-by: Alex Elder <elder@linaro.org>

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 6423f6e..bbeb404 100644 (file)
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -541,7 +541,6 @@ static int rbd_open(struct block_device *bdev, fmode_t mode)
                return -ENOENT;
 
        (void) get_device(&rbd_dev->dev);
-       set_device_ro(bdev, rbd_dev->mapping.read_only);
 
        return 0;
 }
@@ -5060,6 +5059,7 @@ static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
        if (ret)
                goto err_out_disk;
        set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
+       set_disk_ro(rbd_dev->disk, rbd_dev->mapping.read_only);
 
        ret = rbd_bus_add_dev(rbd_dev);
        if (ret)