lkml.org 
[lkml]   [2015]   [Jul]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 1/3] xen-blkfront: introduce blkfront_gather_backend_features()
El 21/07/15 a les 5.30, Bob Liu ha escrit:
> There is a bug when migrate from !feature-persistent host to feature-persistent
> host, because domU still think new host/backend don't support persistent.
> Dmesg like:
> backed has not unmapped grant: 839
> backed has not unmapped grant: 773
> backed has not unmapped grant: 773
> backed has not unmapped grant: 773
> backed has not unmapped grant: 839
>
> The fix is to recheck feature-persistent of new backend in blkif_recover().
> See: https://lkml.org/lkml/2015/5/25/469
>
> As Roger suggested, we can split the part of blkfront_connect that checks for
> optional features, like persistent grants, indirect descriptors and
> flush/barrier features to a separate function and call it from both
> blkfront_connect and blkif_recover
>
> Signed-off-by: Bob Liu <bob.liu@oracle.com>

Thanks for taking care of this. The patch looks fine, just one minor nit.

> ---
> drivers/block/xen-blkfront.c | 118 +++++++++++++++++++++++-------------------
> 1 file changed, 66 insertions(+), 52 deletions(-)
>
> diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
> index 5b45ee5..e266d17 100644
> --- a/drivers/block/xen-blkfront.c
> +++ b/drivers/block/xen-blkfront.c
> @@ -181,6 +181,7 @@ static DEFINE_SPINLOCK(minor_lock);
> ((_segs + SEGS_PER_INDIRECT_FRAME - 1)/SEGS_PER_INDIRECT_FRAME)
>
> static int blkfront_setup_indirect(struct blkfront_info *info);
> +static void blkfront_gather_backend_features(struct blkfront_info *info);
>
> static int get_id_from_freelist(struct blkfront_info *info)
> {
> @@ -1514,6 +1515,7 @@ static int blkif_recover(struct blkfront_info *info)
> info->shadow_free = info->ring.req_prod_pvt;
> info->shadow[BLK_RING_SIZE(info)-1].req.u.rw.id = 0x0fffffff;
>
> + blkfront_gather_backend_features(info);
> rc = blkfront_setup_indirect(info);

AFAICT you can put the call to blkfront_setup_indirect inside of
blkfront_gather_backend_features, like it's done for blkfront_setup_discard.

Roger.


\
 
 \ /
  Last update: 2015-07-21 11:41    [W:0.588 / U:0.036 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site