5 files changed, 79 insertions, 185 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index c9a45f49019d..46e9ac526872 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -514,12 +514,23 @@ static int init_forechannel_attrs(struct svc_rqst *rqstp,
         return status;
 }
 
+static void
+free_session_slots(struct nfsd4_session *ses)
+{
+        int i;
+
+        for (i = 0; i < ses->se_fchannel.maxreqs; i++)
+                kfree(ses->se_slots[i]);
+}
+
 static int
 alloc_init_session(struct svc_rqst *rqstp, struct nfs4_client *clp,
                    struct nfsd4_create_session *cses)
 {
         struct nfsd4_session *new, tmp;
-        int idx, status = nfserr_serverfault, slotsize;
+        struct nfsd4_slot *sp;
+        int idx, slotsize, cachesize, i;
+        int status;
 
         memset(&tmp, 0, sizeof(tmp));
 
@@ -530,14 +541,27 @@ alloc_init_session(struct svc_rqst *rqstp, struct nfs4_client *clp,
         if (status)
                 goto out;
 
-        /* allocate struct nfsd4_session and slot table in one piece */
-        slotsize = tmp.se_fchannel.maxreqs * sizeof(struct nfsd4_slot);
+        BUILD_BUG_ON(NFSD_MAX_SLOTS_PER_SESSION * sizeof(struct nfsd4_slot)
+                     + sizeof(struct nfsd4_session) > PAGE_SIZE);
+
+        status = nfserr_serverfault;
+        /* allocate struct nfsd4_session and slot table pointers in one piece */
+        slotsize = tmp.se_fchannel.maxreqs * sizeof(struct nfsd4_slot *);
         new = kzalloc(sizeof(*new) + slotsize, GFP_KERNEL);
         if (!new)
                 goto out;
 
         memcpy(new, &tmp, sizeof(*new));
 
+        /* allocate each struct nfsd4_slot and data cache in one piece */
+        cachesize = new->se_fchannel.maxresp_cached - NFSD_MIN_HDR_SEQ_SZ;
+        for (i = 0; i < new->se_fchannel.maxreqs; i++) {
+                sp = kzalloc(sizeof(*sp) + cachesize, GFP_KERNEL);
+                if (!sp)
+                        goto out_free;
+                new->se_slots[i] = sp;
+        }
+
         new->se_client = clp;
         gen_sessionid(new);
         idx = hash_sessionid(&new->se_sessionid);
@@ -554,6 +578,10 @@ alloc_init_session(struct svc_rqst *rqstp, struct nfs4_client *clp,
         status = nfs_ok;
 out:
         return status;
+out_free:
+        free_session_slots(new);
+        kfree(new);
+        goto out;
 }
 
 /* caller must hold sessionid_lock */
@@ -596,22 +624,16 @@ release_session(struct nfsd4_session *ses)
         nfsd4_put_session(ses);
 }
 
-static void nfsd4_release_respages(struct page **respages, short resused);
-
 void
 free_session(struct kref *kref)
 {
         struct nfsd4_session *ses;
-        int i;
 
         ses = container_of(kref, struct nfsd4_session, se_ref);
-        for (i = 0; i < ses->se_fchannel.maxreqs; i++) {
-                struct nfsd4_cache_entry *e = &ses->se_slots[i].sl_cache_entry;
-                nfsd4_release_respages(e->ce_respages, e->ce_resused);
-        }
         spin_lock(&nfsd_drc_lock);
         nfsd_drc_mem_used -= ses->se_fchannel.maxreqs * NFSD_SLOT_CACHE_SIZE;
         spin_unlock(&nfsd_drc_lock);
+        free_session_slots(ses);
         kfree(ses);
 }
 
@@ -968,116 +990,31 @@ out_err:
         return;
 }
 
-void
-nfsd4_set_statp(struct svc_rqst *rqstp, __be32 *statp)
-{
-        struct nfsd4_compoundres *resp = rqstp->rq_resp;
-
-        resp->cstate.statp = statp;
-}
-
-/*
- * Dereference the result pages.
- */
-static void
-nfsd4_release_respages(struct page **respages, short resused)
-{
-        int i;
-
-        dprintk("--> %s\n", __func__);
-        for (i = 0; i < resused; i++) {
-                if (!respages[i])
-                        continue;
-                put_page(respages[i]);
-                respages[i] = NULL;
-        }
-}
-
-static void
-nfsd4_copy_pages(struct page **topages, struct page **frompages, short count)
-{
-        int i;
-
-        for (i = 0; i < count; i++) {
-                topages[i] = frompages[i];
-                if (!topages[i])
-                        continue;
-                get_page(topages[i]);
-        }
-}
-
 /*
- * Cache the reply pages up to NFSD_PAGES_PER_SLOT + 1, clearing the previous
- * pages. We add a page to NFSD_PAGES_PER_SLOT for the case where the total
- * length of the XDR response is less than se_fmaxresp_cached
- * (NFSD_PAGES_PER_SLOT * PAGE_SIZE) but the xdr_buf pages is used for a
- * of the reply (e.g. readdir).
- *
- * Store the base and length of the rq_req.head[0] page
- * of the NFSv4.1 data, just past the rpc header.
+ * Cache a reply. nfsd4_check_drc_limit() has bounded the cache size.
  */
 void
 nfsd4_store_cache_entry(struct nfsd4_compoundres *resp)
 {
-        struct nfsd4_cache_entry *entry = &resp->cstate.slot->sl_cache_entry;
-        struct svc_rqst *rqstp = resp->rqstp;
-        struct kvec *resv = &rqstp->rq_res.head[0];
-
-        dprintk("--> %s entry %p\n", __func__, entry);
+        struct nfsd4_slot *slot = resp->cstate.slot;
+        unsigned int base;
 
-        nfsd4_release_respages(entry->ce_respages, entry->ce_resused);
-        entry->ce_opcnt = resp->opcnt;
-        entry->ce_status = resp->cstate.status;
+        dprintk("--> %s slot %p\n", __func__, slot);
 
-        /*
-         * Don't need a page to cache just the sequence operation - the slot
-         * does this for us!
-         */
+        slot->sl_opcnt = resp->opcnt;
+        slot->sl_status = resp->cstate.status;
 
         if (nfsd4_not_cached(resp)) {
-                entry->ce_resused = 0;
-                entry->ce_rpchdrlen = 0;
-                dprintk("%s Just cache SEQUENCE. ce_cachethis %d\n", __func__,
-                        resp->cstate.slot->sl_cache_entry.ce_cachethis);
+                slot->sl_datalen = 0;
                 return;
         }
-        entry->ce_resused = rqstp->rq_resused;
-        if (entry->ce_resused > NFSD_PAGES_PER_SLOT + 1)
-                entry->ce_resused = NFSD_PAGES_PER_SLOT + 1;
-        nfsd4_copy_pages(entry->ce_respages, rqstp->rq_respages,
-                         entry->ce_resused);
-        entry->ce_datav.iov_base = resp->cstate.statp;
-        entry->ce_datav.iov_len = resv->iov_len - ((char *)resp->cstate.statp -
-                                (char *)page_address(rqstp->rq_respages[0]));
-        /* Current request rpc header length*/
-        entry->ce_rpchdrlen = (char *)resp->cstate.statp -
-                                (char *)page_address(rqstp->rq_respages[0]);
-}
-
-/*
- * We keep the rpc header, but take the nfs reply from the replycache.
- */
-static int
-nfsd41_copy_replay_data(struct nfsd4_compoundres *resp,
-                        struct nfsd4_cache_entry *entry)
-{
-        struct svc_rqst *rqstp = resp->rqstp;
-        struct kvec *resv = &resp->rqstp->rq_res.head[0];
-        int len;
-
-        /* Current request rpc header length*/
-        len = (char *)resp->cstate.statp -
-                        (char *)page_address(rqstp->rq_respages[0]);
-        if (entry->ce_datav.iov_len + len > PAGE_SIZE) {
-                dprintk("%s v41 cached reply too large (%Zd).\n", __func__,
-                        entry->ce_datav.iov_len);
-                return 0;
-        }
-        /* copy the cached reply nfsd data past the current rpc header */
-        memcpy((char *)resv->iov_base + len, entry->ce_datav.iov_base,
-                entry->ce_datav.iov_len);
-        resv->iov_len = len + entry->ce_datav.iov_len;
-        return 1;
+        slot->sl_datalen = (char *)resp->p - (char *)resp->cstate.datap;
+        base = (char *)resp->cstate.datap -
+                                        (char *)resp->xbuf->head[0].iov_base;
+        if (read_bytes_from_xdr_buf(resp->xbuf, base, slot->sl_data,
+                                    slot->sl_datalen))
+                WARN("%s: sessions DRC could not cache compound\n", __func__);
+        return;
 }
 
 /*
@@ -1095,14 +1032,14 @@ nfsd4_enc_sequence_replay(struct nfsd4_compoundargs *args,
         struct nfsd4_slot *slot = resp->cstate.slot;
 
         dprintk("--> %s resp->opcnt %d cachethis %u \n", __func__,
-                resp->opcnt, resp->cstate.slot->sl_cache_entry.ce_cachethis);
+                resp->opcnt, resp->cstate.slot->sl_cachethis);
 
         /* Encode the replayed sequence operation */
         op = &args->ops[resp->opcnt - 1];
         nfsd4_encode_operation(resp, op);
 
         /* Return nfserr_retry_uncached_rep in next operation. */
-        if (args->opcnt > 1 && slot->sl_cache_entry.ce_cachethis == 0) {
+        if (args->opcnt > 1 && slot->sl_cachethis == 0) {
                 op = &args->ops[resp->opcnt++];
                 op->status = nfserr_retry_uncached_rep;
                 nfsd4_encode_operation(resp, op);
@@ -1111,57 +1048,29 @@ nfsd4_enc_sequence_replay(struct nfsd4_compoundargs *args,
 }
 
 /*
- * Keep the first page of the replay. Copy the NFSv4.1 data from the first
- * cached page.  Replace any futher replay pages from the cache.
+ * The sequence operation is not cached because we can use the slot and
+ * session values.
  */
 __be32
 nfsd4_replay_cache_entry(struct nfsd4_compoundres *resp,
                          struct nfsd4_sequence *seq)
 {
-        struct nfsd4_cache_entry *entry = &resp->cstate.slot->sl_cache_entry;
+        struct nfsd4_slot *slot = resp->cstate.slot;
         __be32 status;
 
-        dprintk("--> %s entry %p\n", __func__, entry);
-
-        /*
-         * If this is just the sequence operation, we did not keep
-         * a page in the cache entry because we can just use the
-         * slot info stored in struct nfsd4_sequence that was checked
-         * against the slot in nfsd4_sequence().
-         *
-         * This occurs when seq->cachethis is FALSE, or when the client
-         * session inactivity timer fires and a solo sequence operation
-         * is sent (lease renewal).
-         */
+        dprintk("--> %s slot %p\n", __func__, slot);
 
         /* Either returns 0 or nfserr_retry_uncached */
         status = nfsd4_enc_sequence_replay(resp->rqstp->rq_argp, resp);
         if (status == nfserr_retry_uncached_rep)
                 return status;
 
-        if (!nfsd41_copy_replay_data(resp, entry)) {
-                /*
-                 * Not enough room to use the replay rpc header, send the
-                 * cached header. Release all the allocated result pages.
-                 */
-                svc_free_res_pages(resp->rqstp);
-                nfsd4_copy_pages(resp->rqstp->rq_respages, entry->ce_respages,
-                        entry->ce_resused);
-        } else {
-                /* Release all but the first allocated result page */
-
-                resp->rqstp->rq_resused--;
-                svc_free_res_pages(resp->rqstp);
-
-                nfsd4_copy_pages(&resp->rqstp->rq_respages[1],
-                                 &entry->ce_respages[1],
-                                 entry->ce_resused - 1);
-        }
+        /* The sequence operation has been encoded, cstate->datap set. */
+        memcpy(resp->cstate.datap, slot->sl_data, slot->sl_datalen);
 
-        resp->rqstp->rq_resused = entry->ce_resused;
-        resp->opcnt = entry->ce_opcnt;
-        resp->cstate.iovlen = entry->ce_datav.iov_len + entry->ce_rpchdrlen;
-        status = entry->ce_status;
+        resp->opcnt = slot->sl_opcnt;
+        resp->p = resp->cstate.datap + XDR_QUADLEN(slot->sl_datalen);
+        status = slot->sl_status;
 
         return status;
 }
@@ -1493,7 +1402,7 @@ nfsd4_sequence(struct svc_rqst *rqstp,
         if (seq->slotid >= session->se_fchannel.maxreqs)
                 goto out;
 
-        slot = &session->se_slots[seq->slotid];
+        slot = session->se_slots[seq->slotid];
         dprintk("%s: slotid %d\n", __func__, seq->slotid);
 
         /* We do not negotiate the number of slots yet, so set the
@@ -1506,7 +1415,7 @@ nfsd4_sequence(struct svc_rqst *rqstp,
                 cstate->slot = slot;
                 cstate->session = session;
                 /* Return the cached reply status and set cstate->status
-                 * for nfsd4_svc_encode_compoundres processing */
+                 * for nfsd4_proc_compound processing */
                 status = nfsd4_replay_cache_entry(resp, seq);
                 cstate->status = nfserr_replay_cache;
                 goto out;
@@ -1517,7 +1426,7 @@ nfsd4_sequence(struct svc_rqst *rqstp,
         /* Success! bump slot seqid */
         slot->sl_inuse = true;
         slot->sl_seqid = seq->seqid;
-        slot->sl_cache_entry.ce_cachethis = seq->cachethis;
+        slot->sl_cachethis = seq->cachethis;
 
         cstate->slot = slot;
         cstate->session = session;
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 20c5e3db0660..00ed16a18497 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -3057,6 +3057,7 @@ nfsd4_encode_sequence(struct nfsd4_compoundres *resp, int nfserr,
         WRITE32(0);
 
         ADJUST_ARGS();
+        resp->cstate.datap = p; /* DRC cache data pointer */
         return 0;
 }
 
@@ -3159,7 +3160,7 @@ static int nfsd4_check_drc_limit(struct nfsd4_compoundres *resp)
                 return status;
 
         session = resp->cstate.session;
-        if (session == NULL || slot->sl_cache_entry.ce_cachethis == 0)
+        if (session == NULL || slot->sl_cachethis == 0)
                 return status;
 
         if (resp->opcnt >= args->opcnt)
@@ -3284,6 +3285,7 @@ nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compo
         /*
          * All that remains is to write the tag and operation count...
          */
+        struct nfsd4_compound_state *cs = &resp->cstate;
         struct kvec *iov;
         p = resp->tagp;
         *p++ = htonl(resp->taglen);
@@ -3297,15 +3299,10 @@ nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compo
                 iov = &rqstp->rq_res.head[0];
         iov->iov_len = ((char*)resp->p) - (char*)iov->iov_base;
         BUG_ON(iov->iov_len > PAGE_SIZE);
-        if (nfsd4_has_session(&resp->cstate)) {
-                if (resp->cstate.status == nfserr_replay_cache &&
-                                !nfsd4_not_cached(resp)) {
-                        iov->iov_len = resp->cstate.iovlen;
-                } else {
-                        nfsd4_store_cache_entry(resp);
-                        dprintk("%s: SET SLOT STATE TO AVAILABLE\n", __func__);
-                        resp->cstate.slot->sl_inuse = 0;
-                }
+        if (nfsd4_has_session(cs) && cs->status != nfserr_replay_cache) {
+                nfsd4_store_cache_entry(resp);
+                dprintk("%s: SET SLOT STATE TO AVAILABLE\n", __func__);
+                resp->cstate.slot->sl_inuse = false;
                 nfsd4_put_session(resp->cstate.session);
         }
         return 1;
diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index 675d395c4ab6..4472449c0937 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -577,10 +577,6 @@ nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
                 + rqstp->rq_res.head[0].iov_len;
         rqstp->rq_res.head[0].iov_len += sizeof(__be32);
 
-        /* NFSv4.1 DRC requires statp */
-        if (rqstp->rq_vers == 4)
-                nfsd4_set_statp(rqstp, statp);
-
         /* Now call the procedure handler, and encode NFS status. */
         nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
         nfserr = map_new_errors(rqstp->rq_vers, nfserr);
diff --git a/include/linux/nfsd/state.h b/include/linux/nfsd/state.h
index ff0b771efde6..70ef5f4abbbc 100644
--- a/include/linux/nfsd/state.h
+++ b/include/linux/nfsd/state.h
@@ -94,30 +94,23 @@ struct nfs4_cb_conn {
 
 /* Maximum number of slots per session. 160 is useful for long haul TCP */
 #define NFSD_MAX_SLOTS_PER_SESSION     160
-/* Maximum number of pages per slot cache entry */
-#define NFSD_PAGES_PER_SLOT     1
-#define NFSD_SLOT_CACHE_SIZE            PAGE_SIZE
 /* Maximum number of operations per session compound */
 #define NFSD_MAX_OPS_PER_COMPOUND       16
+/* Maximum  session per slot cache size */
+#define NFSD_SLOT_CACHE_SIZE            1024
 /* Maximum number of NFSD_SLOT_CACHE_SIZE slots per session */
 #define NFSD_CACHE_SIZE_SLOTS_PER_SESSION       32
 #define NFSD_MAX_MEM_PER_SESSION  \
                 (NFSD_CACHE_SIZE_SLOTS_PER_SESSION * NFSD_SLOT_CACHE_SIZE)
 
-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;
-};
-
 struct nfsd4_slot {
-        bool                            sl_inuse;
-        u32                             sl_seqid;
-        struct nfsd4_cache_entry        sl_cache_entry;
+        bool    sl_inuse;
+        bool    sl_cachethis;
+        u16     sl_opcnt;
+        u32     sl_seqid;
+        __be32  sl_status;
+        u32     sl_datalen;
+        char    sl_data[];
 };
 
 struct nfsd4_channel_attrs {
@@ -159,7 +152,7 @@ struct nfsd4_session {
         struct nfs4_sessionid   se_sessionid;
         struct nfsd4_channel_attrs se_fchannel;
         struct nfsd4_channel_attrs se_bchannel;
-        struct nfsd4_slot       se_slots[];     /* forward channel slots */
+        struct nfsd4_slot       *se_slots[];    /* forward channel slots */
 };
 
 static inline void
diff --git a/include/linux/nfsd/xdr4.h b/include/linux/nfsd/xdr4.h
index 3f716607c86d..73164c2b3d29 100644
--- a/include/linux/nfsd/xdr4.h
+++ b/include/linux/nfsd/xdr4.h
@@ -51,7 +51,7 @@ struct nfsd4_compound_state {
         /* For sessions DRC */
         struct nfsd4_session    *session;
         struct nfsd4_slot       *slot;
-        __be32                  *statp;
+        __be32                  *datap;
         size_t                  iovlen;
         u32                     minorversion;
         u32                     status;
@@ -472,8 +472,7 @@ static inline bool nfsd4_is_solo_sequence(struct nfsd4_compoundres *resp)
 
 static inline bool nfsd4_not_cached(struct nfsd4_compoundres *resp)
 {
-        return !resp->cstate.slot->sl_cache_entry.ce_cachethis ||
-                        nfsd4_is_solo_sequence(resp);
+        return !resp->cstate.slot->sl_cachethis || nfsd4_is_solo_sequence(resp);
 }
 
 #define NFS4_SVC_XDRSIZE                sizeof(struct nfsd4_compoundargs)