NFSv4.1/pNFS: Don't queue up a new commit if the layout segment is invalid

If the layout segment is invalid, then we should not be adding more
write requests to the commit list. Instead, those writes should be
replayed after requesting a new layout.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

fs/nfs/callback_proc.c

@@ -233,6 +233,8 @@ static u32 initiate_file_draining(struct nfs_client *clp,
 unlock:
 	spin_unlock(&ino->i_lock);
 	pnfs_free_lseg_list(&free_me_list);
+	/* Free all lsegs that are attached to commit buckets */
+	nfs_commit_inode(ino, 0);
 	pnfs_put_layout_hdr(lo);
 	trace_nfs4_cb_layoutrecall_file(clp, &args->cbl_fh, ino,
 			&args->cbl_stateid, -rv);

fs/nfs/direct.c

@@ -721,8 +721,20 @@ static void nfs_direct_commit_complete(struct nfs_commit_data *data)
 		nfs_direct_write_complete(dreq, data->inode);
 }
 
+static void nfs_direct_resched_write(struct nfs_commit_info *cinfo,
+		struct nfs_page *req)
+{
+	struct nfs_direct_req *dreq = cinfo->dreq;
+
+	spin_lock(&dreq->lock);
+	dreq->flags = NFS_ODIRECT_RESCHED_WRITES;
+	spin_unlock(&dreq->lock);
+	nfs_mark_request_commit(req, NULL, cinfo, 0);
+}
+
 static const struct nfs_commit_completion_ops nfs_direct_commit_completion_ops = {
 	.completion = nfs_direct_commit_complete,
+	.resched_write = nfs_direct_resched_write,
 };
 
 static void nfs_direct_commit_schedule(struct nfs_direct_req *dreq)

fs/nfs/pnfs.c

@@ -703,6 +703,8 @@ pnfs_layout_free_bulk_destroy_list(struct list_head *layout_list,
 			ret = -EAGAIN;
 		spin_unlock(&inode->i_lock);
 		pnfs_free_lseg_list(&lseg_list);
+		/* Free all lsegs that are attached to commit buckets */
+		nfs_commit_inode(inode, 0);
 		pnfs_put_layout_hdr(lo);
 		iput(inode);
 	}
@@ -1811,6 +1813,7 @@ void pnfs_error_mark_layout_for_return(struct inode *inode,
 	pnfs_mark_matching_lsegs_return(lo, &free_me, &range);
 	spin_unlock(&inode->i_lock);
 	pnfs_free_lseg_list(&free_me);
+	nfs_commit_inode(inode, 0);
 }
 EXPORT_SYMBOL_GPL(pnfs_error_mark_layout_for_return);
 

fs/nfs/pnfs.h

@@ -412,6 +412,12 @@ pnfs_get_lseg(struct pnfs_layout_segment *lseg)
 	return lseg;
 }
 
+static inline bool
+pnfs_is_valid_lseg(struct pnfs_layout_segment *lseg)
+{
+	return test_bit(NFS_LSEG_VALID, &lseg->pls_flags) != 0;
+}
+
 /* Return true if a layout driver is being used for this mountpoint */
 static inline int pnfs_enabled_sb(struct nfs_server *nfss)
 {

fs/nfs/pnfs_nfs.c

@@ -868,6 +868,11 @@ pnfs_layout_mark_request_commit(struct nfs_page *req,
 	buckets = cinfo->ds->buckets;
 	list = &buckets[ds_commit_idx].written;
 	if (list_empty(list)) {
+		if (!pnfs_is_valid_lseg(lseg)) {
+			spin_unlock(cinfo->lock);
+			cinfo->completion_ops->resched_write(cinfo, req);
+			return;
+		}
 		/* Non-empty buckets hold a reference on the lseg.  That ref
 		 * is normally transferred to the COMMIT call and released
 		 * there.  It could also be released if the last req is pulled

fs/nfs/write.c

@@ -1676,6 +1676,13 @@ void nfs_retry_commit(struct list_head *page_list,
 }
 EXPORT_SYMBOL_GPL(nfs_retry_commit);
 
+static void
+nfs_commit_resched_write(struct nfs_commit_info *cinfo,
+		struct nfs_page *req)
+{
+	__set_page_dirty_nobuffers(req->wb_page);
+}
+
 /*
  * Commit dirty pages
  */
@@ -1777,6 +1784,7 @@ static const struct rpc_call_ops nfs_commit_ops = {
 
 static const struct nfs_commit_completion_ops nfs_commit_completion_ops = {
 	.completion = nfs_commit_release_pages,
+	.resched_write = nfs_commit_resched_write,
 };
 
 int nfs_generic_commit_list(struct inode *inode, struct list_head *head,
@@ -1823,6 +1831,7 @@ int nfs_commit_inode(struct inode *inode, int how)
 	__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
 	return res;
 }
+EXPORT_SYMBOL_GPL(nfs_commit_inode);
 
 int nfs_write_inode(struct inode *inode, struct writeback_control *wbc)
 {

include/linux/nfs_xdr.h

@@ -1420,10 +1420,12 @@ struct nfs_mds_commit_info {
 	struct list_head	list;
 };
 
+struct nfs_commit_info;
 struct nfs_commit_data;
 struct nfs_inode;
 struct nfs_commit_completion_ops {
 	void (*completion) (struct nfs_commit_data *data);
+	void (*resched_write) (struct nfs_commit_info *, struct nfs_page *);
 };
 
 struct nfs_commit_info {