nfs: call nfs_can_coalesce_requests for every req
Call nfs_can_coalesce_requests for every request, even the first one.
This is needed for future patches to give pg_test a way to inform
add_request to reduce the size of the request.
Now @prev can be null in nfs_can_coalesce_requests and pg_test functions.
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 8223343..f343f49 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -292,6 +292,8 @@
size_t nfs_generic_pg_test(struct nfs_pageio_descriptor *desc,
struct nfs_page *prev, struct nfs_page *req)
{
+ if (!prev)
+ return req->wb_bytes;
/*
* FIXME: ideally we should be able to coalesce all requests
* that are not block boundary aligned, but currently this
@@ -761,17 +763,20 @@
{
size_t size;
- if (!nfs_match_open_context(req->wb_context, prev->wb_context))
- return false;
- if (req->wb_context->dentry->d_inode->i_flock != NULL &&
- !nfs_match_lock_context(req->wb_lock_context, prev->wb_lock_context))
- return false;
- if (req->wb_pgbase != 0)
- return false;
- if (prev->wb_pgbase + prev->wb_bytes != PAGE_CACHE_SIZE)
- return false;
- if (req_offset(req) != req_offset(prev) + prev->wb_bytes)
- return false;
+ if (prev) {
+ if (!nfs_match_open_context(req->wb_context, prev->wb_context))
+ return false;
+ if (req->wb_context->dentry->d_inode->i_flock != NULL &&
+ !nfs_match_lock_context(req->wb_lock_context,
+ prev->wb_lock_context))
+ return false;
+ if (req->wb_pgbase != 0)
+ return false;
+ if (prev->wb_pgbase + prev->wb_bytes != PAGE_CACHE_SIZE)
+ return false;
+ if (req_offset(req) != req_offset(prev) + prev->wb_bytes)
+ return false;
+ }
size = pgio->pg_ops->pg_test(pgio, prev, req);
WARN_ON_ONCE(size && size != req->wb_bytes);
return size > 0;
@@ -788,17 +793,16 @@
static int nfs_pageio_do_add_request(struct nfs_pageio_descriptor *desc,
struct nfs_page *req)
{
+ struct nfs_page *prev = NULL;
if (desc->pg_count != 0) {
- struct nfs_page *prev;
-
prev = nfs_list_entry(desc->pg_list.prev);
- if (!nfs_can_coalesce_requests(prev, req, desc))
- return 0;
} else {
if (desc->pg_ops->pg_init)
desc->pg_ops->pg_init(desc, req);
desc->pg_base = req->wb_pgbase;
}
+ if (!nfs_can_coalesce_requests(prev, req, desc))
+ return 0;
nfs_list_remove_request(req);
nfs_list_add_request(req, &desc->pg_list);
desc->pg_count += req->wb_bytes;