nfsd41: non-page DRC for solo sequence responses

A session inactivity time compound (lease renewal) or a compound where the
sequence operation has sa_cachethis set to FALSE do not require any pages
to be held in the v4.1 DRC. This is because struct nfsd4_slot is already
caching the session information.

Add logic to the nfs41 server to not cache response pages for solo sequence
responses.

Return nfserr_replay_uncached_rep on the operation following the sequence
operation when sa_cachethis is FALSE.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfsd41: use cstate session in nfsd4_replay_cache_entry]
[nfsd41: rename nfsd4_no_page_in_cache]
[nfsd41 rename nfsd4_enc_no_page_replay]
[nfsd41 nfsd4_is_solo_sequence]
[nfsd41 change nfsd4_not_cached return]
Signed-off-by: Andy Adamson <andros@netapp.com>
[changed return type to bool]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfsd41 drop parens in nfsd4_is_solo_sequence call]
Signed-off-by: Andy Adamson <andros@netapp.com>
[changed "== 0" to "!"]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

2 files changed, 15 insertions, 1 deletions

diff --git a/include/linux/nfsd/state.h b/include/linux/nfsd/state.h
index f063df7ad134..18dcffa57f77 100644
--- a/include/linux/nfsd/state.h
+++ b/include/linux/nfsd/state.h
@@ -110,6 +110,7 @@ struct nfsd4_cache_entry {
         __be32          ce_status;
         struct kvec     ce_datav; /* encoded NFSv4.1 data in rq_res.head[0] */
         struct page     *ce_respages[NFSD_PAGES_PER_SLOT + 1];
+        int             ce_cachethis;
         short           ce_resused;
         int             ce_opcnt;
         int             ce_rpchdrlen;
diff --git a/include/linux/nfsd/xdr4.h b/include/linux/nfsd/xdr4.h
index 9468829adb70..486188810a60 100644
--- a/include/linux/nfsd/xdr4.h
+++ b/include/linux/nfsd/xdr4.h
@@ -480,6 +480,18 @@ struct nfsd4_compoundres {
         struct nfsd4_compound_state     cstate;
 };
 
+static inline bool nfsd4_is_solo_sequence(struct nfsd4_compoundres *resp)
+{
+        struct nfsd4_compoundargs *args = resp->rqstp->rq_argp;
+        return args->opcnt == 1;
+}
+
+static inline bool nfsd4_not_cached(struct nfsd4_compoundres *resp)
+{
+        return !resp->cstate.slot->sl_cache_entry.ce_cachethis ||
+                        nfsd4_is_solo_sequence(resp);
+}
+
 #define NFS4_SVC_XDRSIZE                sizeof(struct nfsd4_compoundargs)
 
 static inline void
@@ -510,7 +522,8 @@ extern __be32 nfsd4_setclientid_confirm(struct svc_rqst *rqstp,
                 struct nfsd4_compound_state *,
                 struct nfsd4_setclientid_confirm *setclientid_confirm);
 extern void nfsd4_store_cache_entry(struct nfsd4_compoundres *resp);
-extern __be32 nfsd4_replay_cache_entry(struct nfsd4_compoundres *resp);
+extern __be32 nfsd4_replay_cache_entry(struct nfsd4_compoundres *resp,
+                struct nfsd4_sequence *seq);
 extern __be32 nfsd4_exchange_id(struct svc_rqst *rqstp,
                 struct nfsd4_compound_state *,
 struct nfsd4_exchange_id *);