5 files changed, 69 insertions, 5 deletions

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 9ad81ce0c40f..889f7e5e92e1 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -641,6 +641,7 @@ struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, fmode_t f
         nfs_init_lock_context(&ctx->lock_context);
         ctx->lock_context.open_context = ctx;
         INIT_LIST_HEAD(&ctx->list);
+        ctx->mdsthreshold = NULL;
         return ctx;
 }
 
@@ -669,6 +670,7 @@ static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
                 put_rpccred(ctx->cred);
         dput(ctx->dentry);
         nfs_sb_deactive(sb);
+        kfree(ctx->mdsthreshold);
         kfree(ctx);
 }
 
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 8f39bb3ca1b3..e725736ff288 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1782,7 +1782,14 @@ static inline void nfs4_exclusive_attrset(struct nfs4_opendata *opendata, struct
 /*
  * Returns a referenced nfs4_state
  */
-static int _nfs4_do_open(struct inode *dir, struct dentry *dentry, fmode_t fmode, int flags, struct iattr *sattr, struct rpc_cred *cred, struct nfs4_state **res)
+static int _nfs4_do_open(struct inode *dir,
+                        struct dentry *dentry,
+                        fmode_t fmode,
+                        int flags,
+                        struct iattr *sattr,
+                        struct rpc_cred *cred,
+                        struct nfs4_state **res,
+                        struct nfs4_threshold **ctx_th)
 {
         struct nfs4_state_owner  *sp;
         struct nfs4_state     *state = NULL;
@@ -1807,6 +1814,11 @@ static int _nfs4_do_open(struct inode *dir, struct dentry *dentry, fmode_t fmode
         if (opendata == NULL)
                 goto err_put_state_owner;
 
+        if (ctx_th && server->attr_bitmask[2] & FATTR4_WORD2_MDSTHRESHOLD) {
+                opendata->f_attr.mdsthreshold = pnfs_mdsthreshold_alloc();
+                if (!opendata->f_attr.mdsthreshold)
+                        goto err_opendata_put;
+        }
         if (dentry->d_inode != NULL)
                 opendata->state = nfs4_get_open_state(dentry->d_inode, sp);
 
@@ -1832,11 +1844,19 @@ static int _nfs4_do_open(struct inode *dir, struct dentry *dentry, fmode_t fmode
                         nfs_setattr_update_inode(state->inode, sattr);
                 nfs_post_op_update_inode(state->inode, opendata->o_res.f_attr);
         }
+
+        if (pnfs_use_threshold(ctx_th, opendata->f_attr.mdsthreshold, server))
+                *ctx_th = opendata->f_attr.mdsthreshold;
+        else
+                kfree(opendata->f_attr.mdsthreshold);
+        opendata->f_attr.mdsthreshold = NULL;
+
         nfs4_opendata_put(opendata);
         nfs4_put_state_owner(sp);
         *res = state;
         return 0;
 err_opendata_put:
+        kfree(opendata->f_attr.mdsthreshold);
         nfs4_opendata_put(opendata);
 err_put_state_owner:
         nfs4_put_state_owner(sp);
@@ -1846,14 +1866,21 @@ out_err:
 }
 
 
-static struct nfs4_state *nfs4_do_open(struct inode *dir, struct dentry *dentry, fmode_t fmode, int flags, struct iattr *sattr, struct rpc_cred *cred)
+static struct nfs4_state *nfs4_do_open(struct inode *dir,
+                                        struct dentry *dentry,
+                                        fmode_t fmode,
+                                        int flags,
+                                        struct iattr *sattr,
+                                        struct rpc_cred *cred,
+                                        struct nfs4_threshold **ctx_th)
 {
         struct nfs4_exception exception = { };
         struct nfs4_state *res;
         int status;
 
         do {
-                status = _nfs4_do_open(dir, dentry, fmode, flags, sattr, cred, &res);
+                status = _nfs4_do_open(dir, dentry, fmode, flags, sattr, cred,
+                                       &res, ctx_th);
                 if (status == 0)
                         break;
                 /* NOTE: BAD_SEQID means the server and client disagree about the
@@ -2177,7 +2204,8 @@ nfs4_atomic_open(struct inode *dir, struct nfs_open_context *ctx, int open_flags
         struct nfs4_state *state;
 
         /* Protect against concurrent sillydeletes */
-        state = nfs4_do_open(dir, ctx->dentry, ctx->mode, open_flags, attr, ctx->cred);
+        state = nfs4_do_open(dir, ctx->dentry, ctx->mode, open_flags, attr,
+                             ctx->cred, &ctx->mdsthreshold);
         if (IS_ERR(state))
                 return ERR_CAST(state);
         ctx->state = state;
@@ -2779,7 +2807,7 @@ nfs4_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
                 fmode = ctx->mode;
         }
         sattr->ia_mode &= ~current_umask();
-        state = nfs4_do_open(dir, de, fmode, flags, sattr, cred);
+        state = nfs4_do_open(dir, de, fmode, flags, sattr, cred, NULL);
         d_drop(dentry);
         if (IS_ERR(state)) {
                 status = PTR_ERR(state);
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 5d09a36b2cd8..cbcb6aea58a3 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -1630,3 +1630,15 @@ out_free:
         kfree(data);
         goto out;
 }
+
+struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
+{
+        struct nfs4_threshold *thp;
+
+        thp = kzalloc(sizeof(*thp), GFP_NOFS);
+        if (!thp) {
+                dprintk("%s mdsthreshold allocation failed\n", __func__);
+                return NULL;
+        }
+        return thp;
+}
diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h
index 7980756b2f57..29fd23c0efdc 100644
--- a/fs/nfs/pnfs.h
+++ b/fs/nfs/pnfs.h
@@ -227,6 +227,7 @@ int pnfs_read_done_resend_to_mds(struct inode *inode, struct list_head *head,
                         const struct nfs_pgio_completion_ops *compl_ops);
 int pnfs_write_done_resend_to_mds(struct inode *inode, struct list_head *head,
                         const struct nfs_pgio_completion_ops *compl_ops);
+struct nfs4_threshold *pnfs_mdsthreshold_alloc(void);
 
 /* nfs4_deviceid_flags */
 enum {
@@ -360,6 +361,14 @@ static inline int pnfs_return_layout(struct inode *ino)
         return 0;
 }
 
+static inline bool
+pnfs_use_threshold(struct nfs4_threshold **dst, struct nfs4_threshold *src,
+                   struct nfs_server *nfss)
+{
+        return (dst && src && src->bm != 0 &&
+                                        nfss->pnfs_curr_ld->id == src->l_type);
+}
+
 #ifdef NFS_DEBUG
 void nfs4_print_deviceid(const struct nfs4_deviceid *dev_id);
 #else
@@ -485,6 +494,18 @@ static inline int pnfs_layoutcommit_inode(struct inode *inode, bool sync)
         return 0;
 }
 
+static inline bool
+pnfs_use_threshold(struct nfs4_threshold **dst, struct nfs4_threshold *src,
+                   struct nfs_server *nfss)
+{
+        return false;
+}
+
+static inline struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
+{
+        return NULL;
+}
+
 #endif /* CONFIG_NFS_V4_1 */
 
 #endif /* FS_NFS_PNFS_H */
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 80a9385b88ab..ce910cb7d761 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -102,6 +102,7 @@ struct nfs_open_context {
         int error;
 
         struct list_head list;
+        struct nfs4_threshold   *mdsthreshold;
 };
 
 struct nfs_open_dir_context {