On 2020/7/3 6:38, Song Liu wrote:

On Thu, Jul 2, 2020 at 5:05 AM Yufen Yu [off-list ref] wrote:

quoted

After this patch, we can adjust stripe_size by writing value into sysfs
entry, likely, set stripe_size as 16KB:

           echo 16384 > /sys/block/md1/md/stripe_size

Show current stripe_size value:

           cat /sys/block/md1/md/stripe_size

stripe_size should not be bigger than PAGE_SIZE, and it requires to be
multiple of 4096.

I think we can just merge 02/16 into this one.

quoted

Signed-off-by: Yufen Yu <redacted>
---
  drivers/md/raid5.c | 69 +++++++++++++++++++++++++++++++++++++++++++++-
  1 file changed, 68 insertions(+), 1 deletion(-)

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index f0fd01d9122e..a3376a4e4e5c 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c

@@ -6715,7 +6715,74 @@ raid5_show_stripe_size(struct mddev  *mddev, char *page)
  static ssize_t
  raid5_store_stripe_size(struct mddev  *mddev, const char *page, size_t len)
  {
-       return -EINVAL;
+       struct r5conf *conf = mddev->private;

We need mddev_lock(mddev) before accessing mddev->private.

Thanks to point this bug. I will fix it.

Thanks,
Yufen