"block_device" structure removed from "bio"

Hi,

Greetings..!!

I'd like to report an issue which I've been facing in the new kernels (from
4.14 and newer).

Till kernel 4.13, we had the block_device structure as part of

struct *bio* <https://elixir.bootlin.com/linux/v4.4.146/ident/bio> {

       struct *bio*
<https://elixir.bootlin.com/linux/v4.4.146/ident/bio>
*bi_next;     */* request queue link */*

       *struct** block_device
<https://elixir.bootlin.com/linux/v4.4.146/ident/block_device>
*bi_bdev;*

       unsigned int         bi_flags;     */* status, command, etc */*

       int                  bi_error;

       unsigned long        bi_rw;        */* bottom bits READ/WRITE,*

*                                          * top bits priority*

*                                          */*

From kernel 4.14 onwards, this has been removed and I'm facing this error:

*Error: “struct bio” has no member named “bi_bdev”*


Code block (which gives this error):


*dev_t block_device = bio->bi_bdev->bd_dev*

As part of the driver code, I need to retrieve the *block_device* from
the *bio* structure.

As per my understanding there is no existing API to do the same. Can
you please let me know if there is any such API? If not, then can I
expect any fix for the same in the future?

-- 
Regards,
Sarabjeet Singh