Re: [PATCH] bcache: fix incorrect sysfs output value of strip size

[Michael Lyle]

LGTM, applied.

On 02/10/2018 06:30 PM, tang.jun...@zte.com.cn wrote:
> From: Tang Junhui 
> 
> Stripe size is shown as zero when no strip in back end device:
> [root@ceph132 ~]# cat /sys/block/sdd/bcache/stripe_size
> 0.0k
> 
> Actually it should be 1T Bytes (1 << 31 sectors), but in sysfs
> interface, stripe_size was changed from sectors to bytes, and move
> 9 bits left, so the 32 bits variable overflows.
> 
> This patch change the variable to a 64 bits type before moving bits.
> 
> Signed-off-by: Tang Junhui 
> ---
>  drivers/md/bcache/sysfs.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
> index b418409..240cbec 100644
> --- a/drivers/md/bcache/sysfs.c
> +++ b/drivers/md/bcache/sysfs.c
> @@ -170,7 +170,7 @@
>   sysfs_hprint(dirty_data,
>bcache_dev_sectors_dirty(>disk) << 9);
>  
> - sysfs_hprint(stripe_size,   dc->disk.stripe_size << 9);
> + sysfs_hprint(stripe_size,((uint64_t)dc->disk.stripe_size) << 9);
>   var_printf(partial_stripes_expensive,   "%u");
>  
>   var_hprint(sequential_cutoff);
> 

[PATCH] bcache: fix incorrect sysfs output value of strip size

[tang . junhui]

From: Tang Junhui 

Stripe size is shown as zero when no strip in back end device:
[root@ceph132 ~]# cat /sys/block/sdd/bcache/stripe_size
0.0k

Actually it should be 1T Bytes (1 << 31 sectors), but in sysfs
interface, stripe_size was changed from sectors to bytes, and move
9 bits left, so the 32 bits variable overflows.

This patch change the variable to a 64 bits type before moving bits.

Signed-off-by: Tang Junhui 
---
 drivers/md/bcache/sysfs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index b418409..240cbec 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -170,7 +170,7 @@
sysfs_hprint(dirty_data,
 bcache_dev_sectors_dirty(>disk) << 9);
 
-   sysfs_hprint(stripe_size,   dc->disk.stripe_size << 9);
+   sysfs_hprint(stripe_size,((uint64_t)dc->disk.stripe_size) << 9);
var_printf(partial_stripes_expensive,   "%u");
 
var_hprint(sequential_cutoff);
-- 
1.8.3.1