4.0-stable review patch. If anyone has any objections, please let me know.
------------------ From: Peng Tao <[email protected]> commit 1ccbad9f9f9bd36db26a10f0b17fbaf12b3ae93a upstream. For direct read that has IO size larger than rsize, we'll split it into several READ requests and nfs_direct_good_bytes() would count completed bytes incorrectly by eating last zero count reply. Fix it by handling mirror and non-mirror cases differently such that we only count mirrored writes differently. This fixes 5fadeb47("nfs: count DIO good bytes correctly with mirroring"). Reported-by: Jean Spector <[email protected]> Signed-off-by: Peng Tao <[email protected]> Signed-off-by: Trond Myklebust <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- fs/nfs/direct.c | 29 +++++++++++++++++------------ 1 file changed, 17 insertions(+), 12 deletions(-) --- a/fs/nfs/direct.c +++ b/fs/nfs/direct.c @@ -131,20 +131,25 @@ nfs_direct_good_bytes(struct nfs_direct_ 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; - } - - /* update the dreq->count by finding the minimum agreed count from all - * mirrors */ - count = dreq->mirrors[0].count; + if (dreq->mirror_count == 1) { + dreq->mirrors[hdr->pgio_mirror_idx].count += hdr->good_bytes; + dreq->count += hdr->good_bytes; + } else { + /* mirrored writes */ + 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; + } + /* update the dreq->count by finding the minimum agreed count from all + * mirrors */ + count = dreq->mirrors[0].count; - for (i = 1; i < dreq->mirror_count; i++) - count = min(count, dreq->mirrors[i].count); + for (i = 1; i < dreq->mirror_count; i++) + count = min(count, dreq->mirrors[i].count); - dreq->count = count; + dreq->count = count; + } } /* -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
