Commit 781fc49a authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

loop: create a lo_can_use_dio helper 



Factor out a part of __loop_update_dio in preparation for further
refactoring.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250110073750.1582447-4-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 4155adb0

drivers/block/loop.c

+14 −11
Original line number Diff line number Diff line
@@ -182,26 +182,29 @@ static bool lo_bdev_can_use_dio(struct loop_device *lo, 
	return true;

}



static void __loop_update_dio(struct loop_device *lo, bool dio)

static bool lo_can_use_dio(struct loop_device *lo)

{

	struct file *file = lo->lo_backing_file;

	struct inode *inode = file->f_mapping->host;

	struct block_device *backing_bdev = NULL;

	bool use_dio;

	struct inode *inode = lo->lo_backing_file->f_mapping->host;



	if (!(lo->lo_backing_file->f_mode & FMODE_CAN_ODIRECT))

		return false;



	if (S_ISBLK(inode->i_mode))

		backing_bdev = I_BDEV(inode);

	else if (inode->i_sb->s_bdev)

		backing_bdev = inode->i_sb->s_bdev;

		return lo_bdev_can_use_dio(lo, I_BDEV(inode));

	if (inode->i_sb->s_bdev)

		return lo_bdev_can_use_dio(lo, inode->i_sb->s_bdev);

	return true;

}



	use_dio = dio && (file->f_mode & FMODE_CAN_ODIRECT) &&

		(!backing_bdev || lo_bdev_can_use_dio(lo, backing_bdev));

static void __loop_update_dio(struct loop_device *lo, bool dio)

{

	bool use_dio = dio && lo_can_use_dio(lo);



	if (lo->use_dio == use_dio)

		return;



	/* flush dirty pages before changing direct IO */

	vfs_fsync(file, 0);

	vfs_fsync(lo->lo_backing_file, 0);



	/*

	 * The flag of LO_FLAGS_DIRECT_IO is handled similarly with