ore: Remove support of partial IO request (NFS crash)
Boaz Harrosh [Fri, 8 Jun 2012 01:30:40 +0000 (04:30 +0300)]
commit 62b62ad873f2accad9222a4d7ffbe1e93f6714c1 upstream.

Do to OOM situations the ore might fail to allocate all resources
needed for IO of the full request. If some progress was possible
it would proceed with a partial/short request, for the sake of
forward progress.

Since this crashes NFS-core and exofs is just fine without it just
remove this contraption, and fail.

TODO:
Support real forward progress with some reserved allocations
of resources, such as mem pools and/or bio_sets

[Bug since 3.2 Kernel]
CC: Benny Halevy <bhalevy@tonian.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fs/exofs/ore.c

index 49cf230..24a49d4 100644 (file)
@@ -735,13 +735,7 @@ static int _prepare_for_striping(struct ore_io_state *ios)
 out:
        ios->numdevs = devs_in_group;
        ios->pages_consumed = cur_pg;
-       if (unlikely(ret)) {
-               if (length == ios->length)
-                       return ret;
-               else
-                       ios->length -= length;
-       }
-       return 0;
+       return ret;
 }
 
 int ore_create(struct ore_io_state *ios)