Commit a17ece76 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

loop: regularize upgrading the block size for direct I/O 



The LOOP_CONFIGURE path automatically upgrades the block size to that
of the underlying file for O_DIRECT file descriptors, but the
LOOP_SET_BLOCK_SIZE path does not.  Fix this by lifting the code to
pick the block size into common code.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
Reviewed-by: default avatarBart Van Assche <bvanassche@acm.org>
Reviewed-by: default avatarDamien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240617060532.127975-7-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent ae0d40ff

drivers/block/loop.c

+15 −10
Original line number Diff line number Diff line
@@ -975,10 +975,24 @@ loop_set_status_from_info(struct loop_device *lo, 
	return 0;

}



static unsigned short loop_default_blocksize(struct loop_device *lo,

		struct block_device *backing_bdev)

{

	/* In case of direct I/O, match underlying block size */

	if ((lo->lo_backing_file->f_flags & O_DIRECT) && backing_bdev)

		return bdev_logical_block_size(backing_bdev);

	return SECTOR_SIZE;

}



static int loop_reconfigure_limits(struct loop_device *lo, unsigned short bsize)

{

	struct file *file = lo->lo_backing_file;

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

	struct queue_limits lim;



	if (!bsize)

		bsize = loop_default_blocksize(lo, inode->i_sb->s_bdev);



	lim = queue_limits_start_update(lo->lo_queue);

	lim.logical_block_size = bsize;

	lim.physical_block_size = bsize;
@@ -997,7 +1011,6 @@ static int loop_configure(struct loop_device *lo, blk_mode_t mode, 
	int error;

	loff_t size;

	bool partscan;

	unsigned short bsize;

	bool is_loop;



	if (!file)
@@ -1076,15 +1089,7 @@ static int loop_configure(struct loop_device *lo, blk_mode_t mode, 
	if (!(lo->lo_flags & LO_FLAGS_READ_ONLY) && file->f_op->fsync)

		blk_queue_write_cache(lo->lo_queue, true, false);



	if (config->block_size)

		bsize = config->block_size;

	else if ((lo->lo_backing_file->f_flags & O_DIRECT) && inode->i_sb->s_bdev)

		/* In case of direct I/O, match underlying block size */

		bsize = bdev_logical_block_size(inode->i_sb->s_bdev);

	else

		bsize = 512;



	error = loop_reconfigure_limits(lo, bsize);

	error = loop_reconfigure_limits(lo, config->block_size);

	if (WARN_ON_ONCE(error))

		goto out_unlock;