nfs: fix pg_test page count calculation

We really want sizeof(struct page *) instead. Otherwise we limit
maximum IO size to 64 pages rather than 512 pages on a 64bit system.

Fixes 2e11f829(nfs: cap request size to fit a kmalloced page array).

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Fixes: 2e11f8296d22 ("nfs: cap request size to fit a kmalloced page array")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 7c5718b..fe3ddd2 100644 (file)
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -508,7 +508,7 @@ size_t nfs_generic_pg_test(struct nfs_pageio_descriptor *desc,
         * for it without upsetting the slab allocator.
         */
        if (((mirror->pg_count + req->wb_bytes) >> PAGE_SHIFT) *
-                       sizeof(struct page) > PAGE_SIZE)
+                       sizeof(struct page *) > PAGE_SIZE)
                return 0;
 
        return min(mirror->pg_bsize - mirror->pg_count, (size_t)req->wb_bytes);