On Tue, Apr 06, 2010 at 07:13:58AM -0400, Chris Mason wrote:
> On Tue, Apr 06, 2010 at 03:54:27PM +0800, Yan, Zheng wrote:
> > On Thu, Mar 18, 2010 at 4:45 AM, Josef Bacik <jo...@redhat.com> wrote:
> > > If the amount of free space left in a device is less than what we think
> > > should
> > > be the minimum size, just ignore the minimum size and use the amount we
> > > have. I
> > > ran into this running tests on a 600mb volume, the chunk allocator
> > > wouldn't let
> > > me allocate the last 52mb of the disk for data because we want to have at
> > > least
> > > 64mb chunks for data. This patch fixes that problem. Thanks,
> > >
> > > Signed-off-by: Josef Bacik <jo...@redhat.com>
> > >
> > > diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
> > > index 9df8e3f..1c5b5ba 100644
> > > --- a/fs/btrfs/volumes.c
> > > +++ b/fs/btrfs/volumes.c
> > > @@ -2244,8 +2244,10 @@ again:
> > > do_div(calc_size, stripe_len);
> > > calc_size *= stripe_len;
> > > }
> > > +
> > > /* we don't want tiny stripes */
> > > - calc_size = max_t(u64, min_stripe_size, calc_size);
> > > + if (!looped)
> > > + calc_size = max_t(u64, min_stripe_size, calc_size);
> > >
> > > do_div(calc_size, stripe_len);
> > > calc_size *= stripe_len;
> >
> > I encountered an Oops caused by 'calc_size == 0'. It's likely introduced
> > by this change. (calc_size can be zero after calling do_div)
Ok, anyone object to this:
>From 9f680ce04ea19dabbbafe01b57b61930a9b70741 Mon Sep 17 00:00:00 2001
From: Chris Mason <chris.ma...@oracle.com>
Date: Tue, 6 Apr 2010 09:37:47 -0400
Subject: [PATCH] Btrfs: make sure the chunk allocator doesn't create zero
length chunks
A recent commit allowed for smaller chunks to be created, but didn't
make sure they were always bigger than a stripe. After some divides,
this led to zero length stripes.
Signed-off-by: Chris Mason <chris.ma...@oracle.com>
---
fs/btrfs/volumes.c | 6 ++++++
1 files changed, 6 insertions(+), 0 deletions(-)
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 9bf1f58..b584e9a 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -2249,6 +2249,12 @@ again:
if (!looped)
calc_size = max_t(u64, min_stripe_size, calc_size);
+ /*
+ * we're about to do_div by the stripe_len so lets make sure
+ * we end up with something bigger than a stripe
+ */
+ calc_size = max_t(u64, calc_size, stripe_len * 4);
+
do_div(calc_size, stripe_len);
calc_size *= stripe_len;
--
1.7.0.2
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
