diff mbox series

[v3,2/9] loop: Factor out setting loop device size

Message ID 20200427074222.65369-3-maco@android.com (mailing list archive)
State New, archived
Headers show
Series Add a new LOOP_SET_FD_AND_STATUS ioctl | expand

Commit Message

Martijn Coenen April 27, 2020, 7:42 a.m. UTC 
This code is used repeatedly.

Signed-off-by: Martijn Coenen <maco@android.com>
---
 drivers/block/loop.c | 31 ++++++++++++++++++++++---------
 1 file changed, 22 insertions(+), 9 deletions(-)

Comments

Christoph Hellwig April 27, 2020, 2:53 p.m. UTC | #1 
On Mon, Apr 27, 2020 at 09:42:15AM +0200, Martijn Coenen wrote:
> This code is used repeatedly.
> 
> Signed-off-by: Martijn Coenen <maco@android.com>

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>
diff mbox series

Patch

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index f812f11649d3..4630d098cc54 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -241,12 +241,29 @@  loop_validate_size(loff_t size)
 		return 0;
 }
 
+/**
+ * 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 int
 figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit)
 {
 	int err;
 	loff_t size = get_size(offset, sizelimit, lo->lo_backing_file);
-	struct block_device *bdev = lo->lo_device;
 
 	err = loop_validate_size(size);
 	if (err)
@@ -256,10 +273,9 @@  figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit)
 		lo->lo_offset = offset;
 	if (lo->lo_sizelimit != sizelimit)
 		lo->lo_sizelimit = sizelimit;
-	set_capacity(lo->lo_disk, x);
-	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);
+
 	return 0;
 }
 
@@ -1055,11 +1071,8 @@  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);