[PATCH v5 03/11] loop: Factor out setting loop device size

[Martijn Coenen]

This code is used repeatedly.

Reviewed-by: Christoph Hellwig <h...@lst.de>
Signed-off-by: Martijn Coenen <m...@android.com>
---
 drivers/block/loop.c | 30 +++++++++++++++++++++---------
 1 file changed, 21 insertions(+), 9 deletions(-)

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 00de7fec0ed5..e69ff3c19eff 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -228,20 +228,35 @@ static void __loop_update_dio(struct loop_device *lo, 
bool dio)
                blk_mq_unfreeze_queue(lo->lo_queue);
 }
 
+/**
+ * loop_set_size() - sets device size and notifies userspace
+ * @lo: struct loop_device to set the size for
+ * @size: new size of the loop device
+ *
+ * Callers must validate that the size passed into this function fits into
+ * a sector_t, eg using loop_validate_size()
+ */
+static void loop_set_size(struct loop_device *lo, loff_t size)
+{
+       struct block_device *bdev = lo->lo_device;
+
+       set_capacity(lo->lo_disk, size);
+       bd_set_size(bdev, size << SECTOR_SHIFT);
+       /* let user-space know about the new size */
+       kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, KOBJ_CHANGE);
+}
+
 static void
 figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit)
 {
        loff_t size = get_size(offset, sizelimit, lo->lo_backing_file);
-       struct block_device *bdev = lo->lo_device;
 
        if (lo->lo_offset != offset)
                lo->lo_offset = offset;
        if (lo->lo_sizelimit != sizelimit)
                lo->lo_sizelimit = sizelimit;
-       set_capacity(lo->lo_disk, size);
-       bd_set_size(bdev, (loff_t)get_capacity(bdev->bd_disk) << 9);
-       /* let user-space know about the new size */
-       kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, KOBJ_CHANGE);
+
+       loop_set_size(lo, size);
 }
 
 static inline int
@@ -1034,11 +1049,8 @@ static int loop_set_fd(struct loop_device *lo, fmode_t 
mode,
 
        loop_update_rotational(lo);
        loop_update_dio(lo);
-       set_capacity(lo->lo_disk, size);
-       bd_set_size(bdev, size << 9);
        loop_sysfs_init(lo);
-       /* let user-space know about the new size */
-       kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, KOBJ_CHANGE);
+       loop_set_size(lo, size);
 
        set_blocksize(bdev, S_ISBLK(inode->i_mode) ?
                      block_size(inode->i_bdev) : PAGE_SIZE);
-- 
2.26.2.645.ge9eca65c58-goog