[PATCH 06/20] block: change the hash used for looking up block devices

[Jan Kara]

On Wed 18-11-20 09:47:46, Christoph Hellwig wrote:
> Adding the minor to the major creates tons of pointless conflicts. Just
> use the dev_t itself, which is 32-bits and thus is guaranteed to fit
> into ino_t.
> 
> Signed-off-by: Christoph Hellwig <hch at lst.de>

Fair enough. You can add:

Reviewed-by: Jan Kara <jack at suse.cz>

								Honza

> ---
>  fs/block_dev.c | 26 ++------------------------
>  1 file changed, 2 insertions(+), 24 deletions(-)
> 
> diff --git a/fs/block_dev.c b/fs/block_dev.c
> index d8664f5c1ff669..29db12c3bb501c 100644
> --- a/fs/block_dev.c
> +++ b/fs/block_dev.c
> @@ -870,35 +870,12 @@ void __init bdev_cache_init(void)
>  	blockdev_superblock = bd_mnt->mnt_sb;   /* For writeback */
>  }
>  
> -/*
> - * Most likely _very_ bad one - but then it's hardly critical for small
> - * /dev and can be fixed when somebody will need really large one.
> - * Keep in mind that it will be fed through icache hash function too.
> - */
> -static inline unsigned long hash(dev_t dev)
> -{
> -	return MAJOR(dev)+MINOR(dev);
> -}
> -
> -static int bdev_test(struct inode *inode, void *data)
> -{
> -	return BDEV_I(inode)->bdev.bd_dev == *(dev_t *)data;
> -}
> -
> -static int bdev_set(struct inode *inode, void *data)
> -{
> -	BDEV_I(inode)->bdev.bd_dev = *(dev_t *)data;
> -	return 0;
> -}
> -
>  static struct block_device *bdget(dev_t dev)
>  {
>  	struct block_device *bdev;
>  	struct inode *inode;
>  
> -	inode = iget5_locked(blockdev_superblock, hash(dev),
> -			bdev_test, bdev_set, &dev);
> -
> +	inode = iget_locked(blockdev_superblock, dev);
>  	if (!inode)
>  		return NULL;
>  
> @@ -910,6 +887,7 @@ static struct block_device *bdget(dev_t dev)
>  		bdev->bd_super = NULL;
>  		bdev->bd_inode = inode;
>  		bdev->bd_part_count = 0;
> +		bdev->bd_dev = dev;
>  		inode->i_mode = S_IFBLK;
>  		inode->i_rdev = dev;
>  		inode->i_bdev = bdev;
> -- 
> 2.29.2
> 
-- 
Jan Kara <jack at suse.com>
SUSE Labs, CR