Re: [PATCH 61/78] zram: do not call set_blocksize

[Minchan Kim <minchan@xxxxxxxxxx>]

On Mon, Nov 16, 2020 at 03:57:52PM +0100, Christoph Hellwig wrote:
> set_blocksize is used by file systems to use their preferred buffer cache
> block size.  Block drivers should not set it.
> 
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Acked-by: Minchan Kim <minchan@xxxxxxxxxx>

Thanks.

> ---
>  drivers/block/zram/zram_drv.c | 11 +----------
>  drivers/block/zram/zram_drv.h |  1 -
>  2 files changed, 1 insertion(+), 11 deletions(-)
> 
> diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
> index 3641434a9b154d..d00b5761ec0b21 100644
> --- a/drivers/block/zram/zram_drv.c
> +++ b/drivers/block/zram/zram_drv.c
> @@ -403,13 +403,10 @@ static void reset_bdev(struct zram *zram)
>               return;
>  
>       bdev = zram->bdev;
> -     if (zram->old_block_size)
> -             set_blocksize(bdev, zram->old_block_size);
>       blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
>       /* hope filp_close flush all of IO */
>       filp_close(zram->backing_dev, NULL);
>       zram->backing_dev = NULL;
> -     zram->old_block_size = 0;
>       zram->bdev = NULL;
>       zram->disk->fops = &zram_devops;
>       kvfree(zram->bitmap);
> @@ -454,7 +451,7 @@ static ssize_t backing_dev_store(struct device *dev,
>       struct file *backing_dev = NULL;
>       struct inode *inode;
>       struct address_space *mapping;
> -     unsigned int bitmap_sz, old_block_size = 0;
> +     unsigned int bitmap_sz;
>       unsigned long nr_pages, *bitmap = NULL;
>       struct block_device *bdev = NULL;
>       int err;
> @@ -509,14 +506,8 @@ static ssize_t backing_dev_store(struct device *dev,
>               goto out;
>       }
>  
> -     old_block_size = block_size(bdev);
> -     err = set_blocksize(bdev, PAGE_SIZE);
> -     if (err)
> -             goto out;
> -
>       reset_bdev(zram);
>  
> -     zram->old_block_size = old_block_size;
>       zram->bdev = bdev;
>       zram->backing_dev = backing_dev;
>       zram->bitmap = bitmap;
> diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h
> index f2fd46daa76045..712354a4207c77 100644
> --- a/drivers/block/zram/zram_drv.h
> +++ b/drivers/block/zram/zram_drv.h
> @@ -118,7 +118,6 @@ struct zram {
>       bool wb_limit_enable;
>       u64 bd_wb_limit;
>       struct block_device *bdev;
> -     unsigned int old_block_size;
>       unsigned long *bitmap;
>       unsigned long nr_pages;
>  #endif
> -- 
> 2.29.2
>