| Message ID | 1428495850-7136-1-git-send-email-tao.peng@primarydata.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Apr 8, 2015 at 8:24 PM, Peng Tao <tao.peng@primarydata.com> wrote: > When adding completed bytes, we should just use hdr->good_bytes. > Otherwise if we send multiple requests for one direct IO (due to > rsize/wsize limitation), we'll count completed bytes incorrectly. > > This fixes 5fadeb47("nfs: count DIO good bytes correctly with mirroring"). > > Reported-by: Jean Spector <jean@primarydata.com> > Cc: <stable@vger.kernel.org> # v3.19+ > Signed-off-by: Peng Tao <tao.peng@primarydata.com> > --- > fs/nfs/direct.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c > index e907c8c..645109e 100644 > --- a/fs/nfs/direct.c > +++ b/fs/nfs/direct.c > @@ -132,10 +132,8 @@ nfs_direct_good_bytes(struct nfs_direct_req *dreq, struct nfs_pgio_header *hdr) > WARN_ON_ONCE(hdr->pgio_mirror_idx >= dreq->mirror_count); > > count = dreq->mirrors[hdr->pgio_mirror_idx].count; > - if (count + dreq->io_start < hdr->io_start + hdr->good_bytes) { > - count = hdr->io_start + hdr->good_bytes - dreq->io_start; > - dreq->mirrors[hdr->pgio_mirror_idx].count = count; > - } > + if (count + dreq->io_start < hdr->io_start + hdr->good_bytes) > + dreq->mirrors[hdr->pgio_mirror_idx].count += hdr->good_bytes; oh, speaking too soon. This would actually fail concurrent DIO writers if split requests complete randomly. Please don't merge it! I'll send a updated version. sorry for the noise! Thanks, Tao -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c index e907c8c..645109e 100644 --- a/fs/nfs/direct.c +++ b/fs/nfs/direct.c @@ -132,10 +132,8 @@ nfs_direct_good_bytes(struct nfs_direct_req *dreq, struct nfs_pgio_header *hdr) WARN_ON_ONCE(hdr->pgio_mirror_idx >= dreq->mirror_count); count = dreq->mirrors[hdr->pgio_mirror_idx].count; - if (count + dreq->io_start < hdr->io_start + hdr->good_bytes) { - count = hdr->io_start + hdr->good_bytes - dreq->io_start; - dreq->mirrors[hdr->pgio_mirror_idx].count = count; - } + if (count + dreq->io_start < hdr->io_start + hdr->good_bytes) + dreq->mirrors[hdr->pgio_mirror_idx].count += hdr->good_bytes; /* update the dreq->count by finding the minimum agreed count from all * mirrors */
When adding completed bytes, we should just use hdr->good_bytes. Otherwise if we send multiple requests for one direct IO (due to rsize/wsize limitation), we'll count completed bytes incorrectly. This fixes 5fadeb47("nfs: count DIO good bytes correctly with mirroring"). Reported-by: Jean Spector <jean@primarydata.com> Cc: <stable@vger.kernel.org> # v3.19+ Signed-off-by: Peng Tao <tao.peng@primarydata.com> --- fs/nfs/direct.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)