On Wed, Jun 1, 2011 at 10:51 AM, Benny Halevy <bhalevy@xxxxxxxxxxx> wrote: > On 2011-06-01 17:44, Weston Andros Adamson wrote: >> >> On Jun 1, 2011, at 1:47 AM, Boaz Harrosh wrote: >> >>> On 06/01/2011 06:18 AM, Weston Andros Adamson wrote: >>>> Use nfs_generic_pg_test instead of pnfs_generic_pg_test. >>>> >>>> This fixes the BUG at fs/nfs/write.c:941 introduced by >>>> 89a58e32d9105c01022a757fb32ddc3b51bf0025. >>>> >>>> I was able to trigger this BUG reliably using pynfs in pnfs mode, >>>> by using dd(1) to write many small blocks. >>>> >>>> Signed-off-by: Weston Andros Adamson <dros@xxxxxxxxxx> >>>> --- >>>> Fix proposed by Trond. >>>> >>>> Benny- Does this make sense? >>>> >>>> fs/nfs/nfs4filelayout.c | 2 +- >>>> fs/nfs/pagelist.c | 5 ++++- >>>> include/linux/nfs_page.h | 3 ++- >>>> 3 files changed, 7 insertions(+), 3 deletions(-) >>>> >>>> diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c >>>> index 4269088..1c3bb72 100644 >>>> --- a/fs/nfs/nfs4filelayout.c >>>> +++ b/fs/nfs/nfs4filelayout.c >>>> @@ -661,7 +661,7 @@ filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, >>>> u64 p_stripe, r_stripe; >>>> u32 stripe_unit; >>>> >>>> - if (!pnfs_generic_pg_test(pgio, prev, req)) >>>> + if (!nfs_generic_pg_test(pgio, prev, req)) >>>> return 0; >>>> >>> >>> pnfs_generic_pg_test is the one that gets the layout. >>> >>> What you've done is revert to MDS IO >>> >>> Boaz >> >> Ah, you're right - I didn't even notice that! I usually confirm client -> DS communication with tcpdump. I was working for too long yesterday :) >> >> Patch: recalled. Discussion about a real fix: started. >> >> -dros > > I think the following should work: > > Benny > > git diff --stat -p -M > fs/nfs/nfs4filelayout.c | 10 ++++++++++ > 1 files changed, 10 insertions(+), 0 deletions(-) > > diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c > index 4269088..9f1d445 100644 > --- a/fs/nfs/nfs4filelayout.c > +++ b/fs/nfs/nfs4filelayout.c > @@ -661,6 +661,16 @@ filelayout_pg_test(struct nfs_pageio_descriptor > *pgio, struct nfs_page *prev, > u64 p_stripe, r_stripe; > u32 stripe_unit; > > + /* > + * FIXME: ideally we should be able to coalesce all requests > + * that are not block boundary aligned, but currently this > + * is problematic for the case of bsize < PAGE_CACHE_SIZE, > + * since nfs_flush_multi and nfs_pagein_multi assume you > + * can have only one struct nfs_page. > + */ > + if (desc->pg_bsize < PAGE_SIZE) > + return 0; > + > if (!pnfs_generic_pg_test(pgio, prev, req)) > return 0; > Note this moves a test that was once part of the plain nfs code into the file layout driver. Why don't other drivers need this test? Fred -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
