[v2,1/3] scsi: dpt_i2o: drop stale VIRT_TO_BUS dependency

From: Arnd Bergmann <arnd@arndb.de>

The dpt_i2o driver was fixed to stop using virt_to_bus() in 2008, but
it still has a stale reference in an error handling code path that could
never work.

Fix it up to build without VIRT_TO_BUS and remove the Kconfig dependency.

The alternative to this would be to just remove the driver, as it is
clearly obsolete. The i2o driver layer was removed in 2015 with commit
4a72a7af462d ("staging: remove i2o subsystem"), but the even older
dpt_i2o scsi driver stayed around.

The last non-cleanup patches I could find were from Miquel van Smoorenburg
and Mark Salyzyn back in 2008, they might know if there is any chance
of the hardware still being used anywhere.

Fixes: 67af2b060e02 ("[SCSI] dpt_i2o: move from virt_to_bus/bus_to_virt to dma_alloc_coherent")
Cc: Miquel van Smoorenburg <mikevs@xs4all.net>
Cc: Mark Salyzyn <salyzyn@android.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/scsi/Kconfig   | 2 +-
 drivers/scsi/dpt_i2o.c | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

On 6/17/22 14:57, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> The dpt_i2o driver was fixed to stop using virt_to_bus() in 2008, but
> it still has a stale reference in an error handling code path that could
> never work.
> 
> Fix it up to build without VIRT_TO_BUS and remove the Kconfig dependency.
> 
> The alternative to this would be to just remove the driver, as it is
> clearly obsolete. The i2o driver layer was removed in 2015 with commit
> 4a72a7af462d ("staging: remove i2o subsystem"), but the even older
> dpt_i2o scsi driver stayed around.
> 
> The last non-cleanup patches I could find were from Miquel van Smoorenburg
> and Mark Salyzyn back in 2008, they might know if there is any chance
> of the hardware still being used anywhere.
> 
> Fixes: 67af2b060e02 ("[SCSI] dpt_i2o: move from virt_to_bus/bus_to_virt to dma_alloc_coherent")
> Cc: Miquel van Smoorenburg <mikevs@xs4all.net>
> Cc: Mark Salyzyn <salyzyn@android.com>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>   drivers/scsi/Kconfig   | 2 +-
>   drivers/scsi/dpt_i2o.c | 4 ++--
>   2 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
> index a9fe5152addd..cf75588a2587 100644
> --- a/drivers/scsi/Kconfig
> +++ b/drivers/scsi/Kconfig
> @@ -460,7 +460,7 @@ config SCSI_MVUMI
>   
>   config SCSI_DPT_I2O
>   	tristate "Adaptec I2O RAID support "
> -	depends on SCSI && PCI && VIRT_TO_BUS
> +	depends on SCSI && PCI
>   	help
>   	  This driver supports all of Adaptec's I2O based RAID controllers as
>   	  well as the DPT SmartRaid V cards.  This is an Adaptec maintained
> diff --git a/drivers/scsi/dpt_i2o.c b/drivers/scsi/dpt_i2o.c
> index 2e9155ba7408..55dfe7011912 100644
> --- a/drivers/scsi/dpt_i2o.c
> +++ b/drivers/scsi/dpt_i2o.c
> @@ -52,11 +52,11 @@ MODULE_DESCRIPTION("Adaptec I2O RAID Driver");
>   
>   #include <linux/timer.h>
>   #include <linux/string.h>
> +#include <linux/io.h>
>   #include <linux/ioport.h>
>   #include <linux/mutex.h>
>   
>   #include <asm/processor.h>	/* for boot_cpu_data */
> -#include <asm/io.h>		/* for virt_to_bus, etc. */
>   
>   #include <scsi/scsi.h>
>   #include <scsi/scsi_cmnd.h>
> @@ -2112,7 +2112,7 @@ static irqreturn_t adpt_isr(int irq, void *dev_id)
>   		} else {
>   			/* Ick, we should *never* be here */
>   			printk(KERN_ERR "dpti: reply frame not from pool\n");
> -			reply = (u8 *)bus_to_virt(m);
> +			goto out;
>   		}
>   
>   		if (readl(reply) & MSG_FAIL) {

Reviewed-by: Hannes Reinecke <hare@suse.de>

Personally I wouldn't mind to see this driver gone, as it's being built 
upon the (long-defunct) I2O specification. We already deleted the i2o 
subsystem years ago, so maybe it's time to consign this driver to 
history, too.

Cheers,

Hannes