[PATCH] dm-crypt: never use write same (was Re: [v3.7 Regression] [SCSI] sd: Implement support for WRITE SAME)

[Joseph Salisbury]

On 12/19/2012 04:07 PM, Milan Broz wrote:
> Does this help?
>
> dm-crypt: never use write same
>
> Ciphertext device is not compatible with WRITE SAME,
> disable it for all dmcrypt devices.
>
> Signed-off-by: Milan Broz <mbroz at redhat.com>
>
> --- a/drivers/md/dm-crypt.c
> +++ b/drivers/md/dm-crypt.c
> @@ -1844,6 +1844,12 @@ static int crypt_iterate_devices(struct dm_target *ti,
>   	return fn(ti, cc->dev, cc->start, ti->len, data);
>   }
>   
> +static void crypt_io_hints(struct dm_target *ti,
> +			    struct queue_limits *limits)
> +{
> +	limits->max_write_same_sectors = 0;
> +}
> +
>   static struct target_type crypt_target = {
>   	.name   = "crypt",
>   	.version = {1, 11, 0},
> @@ -1858,6 +1864,7 @@ static struct target_type crypt_target = {
>   	.message = crypt_message,
>   	.merge  = crypt_merge,
>   	.iterate_devices = crypt_iterate_devices,
> +	.io_hints = crypt_io_hints,
>   };
>   
>   static int __init dm_crypt_init(void)
>
Great work, Milan.  Your patch fixes the bug, stops the panic and allows 
dm-crypt to function properly.

Will you be requesting this in v3.8 ?

Thanks again,

Joe