Re: [PATCH] scsi: libsas: Fix declaration of ncq priority attributes

[Damien Le Moal <dlemoal@kernel.org>]

On 3/27/24 11:01, Damien Le Moal wrote:
> Commit b4d3ddd2df7 ("scsi: libsas: Define NCQ Priority sysfs attributes
> for SATA devices") introduced support for ATA NCQ priority control for
> ATA devices managed by libsas. This commit introduces the
> ncq_prio_supported and ncq_prio_enable sysfs device attributes to
> discover and control the use of this features, similarly to libata.
> However, libata publicly declares these device attributes and export
> them for use in ATA low level drivers. This leads to a compilation error
> when libsas and libata are built-in due to the double definition:
> 
> ld: drivers/ata/libata-sata.o:/home/Linux/scsi/drivers/ata/libata-sata.c:900:
> multiple definition of `dev_attr_ncq_prio_supported';
> drivers/scsi/libsas/sas_ata.o:/home/Linux/scsi/drivers/scsi/libsas/sas_ata.c:984:
> first defined here
> ld: drivers/ata/libata-sata.o:/home/Linux/scsi/drivers/ata/libata-sata.c:1026:
> multiple definition of `dev_attr_ncq_prio_enable';
> drivers/scsi/libsas/sas_ata.o:/home/Linux/scsi/drivers/scsi/libsas/sas_ata.c:1022:
> first defined here
> 
> Resolve this problem by directly declaring the libsas attributes instead
> of using the DEVICE_ATTR() macro. And for good measure, the device
> attribute variables are also renamed.
> 
> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
> Fixes: b4d3ddd2df7 ("scsi: libsas: Define NCQ Priority sysfs attributes for SATA devices")
> Signed-off-by: Damien Le Moal <dlemoal@kernel.org>

Forgot to add John to the distribution list...

> ---
>  drivers/scsi/libsas/sas_ata.c | 12 +++++++-----
>  1 file changed, 7 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/scsi/libsas/sas_ata.c b/drivers/scsi/libsas/sas_ata.c
> index b57c041a5544..4c69fc63c119 100644
> --- a/drivers/scsi/libsas/sas_ata.c
> +++ b/drivers/scsi/libsas/sas_ata.c
> @@ -981,7 +981,8 @@ static ssize_t sas_ncq_prio_supported_show(struct device *device,
>  	return sysfs_emit(buf, "%d\n", supported);
>  }
>  
> -DEVICE_ATTR(ncq_prio_supported, S_IRUGO, sas_ncq_prio_supported_show, NULL);
> +static struct device_attribute dev_attr_sas_ncq_prio_supported =
> +	__ATTR(ncq_prio_supported, S_IRUGO, sas_ncq_prio_supported_show, NULL);
>  
>  static ssize_t sas_ncq_prio_enable_show(struct device *device,
>  					struct device_attribute *attr,
> @@ -1019,12 +1020,13 @@ static ssize_t sas_ncq_prio_enable_store(struct device *device,
>  	return len;
>  }
>  
> -DEVICE_ATTR(ncq_prio_enable, S_IRUGO | S_IWUSR,
> -	    sas_ncq_prio_enable_show, sas_ncq_prio_enable_store);
> +static struct device_attribute dev_attr_sas_ncq_prio_enable =
> +	__ATTR(ncq_prio_enable, S_IRUGO | S_IWUSR,
> +	       sas_ncq_prio_enable_show, sas_ncq_prio_enable_store);
>  
>  static struct attribute *sas_ata_sdev_attrs[] = {
> -	&dev_attr_ncq_prio_supported.attr,
> -	&dev_attr_ncq_prio_enable.attr,
> +	&dev_attr_sas_ncq_prio_supported.attr,
> +	&dev_attr_sas_ncq_prio_enable.attr,
>  	NULL
>  };
>  

-- 
Damien Le Moal
Western Digital Research