nfs: chain calls to pg_test
Now that pg_test can change the size of the request (by returning a non-zero
size smaller than the request), pg_test functions that call other
pg_test functions must return the minimum of the result - or 0 if any fail.
Also clean up the logic of some pg_test functions so that all checks are
for contitions where coalescing is not possible.
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
index 9cea935..7a665e0 100644
--- a/fs/nfs/nfs4filelayout.c
+++ b/fs/nfs/nfs4filelayout.c
@@ -928,26 +928,27 @@
filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
struct nfs_page *req)
{
+ unsigned int size;
u64 p_stripe, r_stripe;
u32 stripe_unit;
- if (!pnfs_generic_pg_test(pgio, prev, req) ||
- !nfs_generic_pg_test(pgio, prev, req))
+ /* calls nfs_generic_pg_test */
+ size = pnfs_generic_pg_test(pgio, prev, req);
+ if (!size)
return 0;
- if (!prev)
- return req->wb_bytes;
+ if (prev) {
+ p_stripe = (u64)req_offset(prev);
+ r_stripe = (u64)req_offset(req);
+ stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
- p_stripe = (u64)req_offset(prev);
- r_stripe = (u64)req_offset(req);
- stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
+ do_div(p_stripe, stripe_unit);
+ do_div(r_stripe, stripe_unit);
- do_div(p_stripe, stripe_unit);
- do_div(r_stripe, stripe_unit);
-
- if (p_stripe == r_stripe)
- return req->wb_bytes;
- return 0;
+ if (p_stripe != r_stripe)
+ return 0;
+ }
+ return min(size, req->wb_bytes);
}
static void