diff --git a/fs/nfs/Makefile b/fs/nfs/Makefile
index 5f6db37f461e..af64cf5ea420 100644
--- a/fs/nfs/Makefile
+++ b/fs/nfs/Makefile
@@ -9,7 +9,7 @@ CFLAGS_nfstrace.o += -I$(src)
 nfs-y 			:= client.o dir.o file.o getroot.o inode.o super.o \
 			   io.o direct.o pagelist.o read.o symlink.o unlink.o \
 			   write.o namespace.o mount_clnt.o nfstrace.o \
-			   export.o sysfs.o fs_context.o
+			   export.o sysfs.o fs_context.o localio.o
 nfs-$(CONFIG_ROOT_NFS)	+= nfsroot.o
 nfs-$(CONFIG_SYSCTL)	+= sysctl.o
 nfs-$(CONFIG_NFS_FSCACHE) += fscache.o
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index dd3278dcfca8..288de750fd3b 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -170,6 +170,7 @@ struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
 	}
 
 	INIT_LIST_HEAD(&clp->cl_superblocks);
+	INIT_LIST_HEAD(&clp->cl_local_addrs);
 	clp->cl_rpcclient = ERR_PTR(-EINVAL);
 
 	clp->cl_flags = cl_init->init_flags;
@@ -183,6 +184,7 @@ struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
 
 	clp->cl_principal = "*";
 	clp->cl_xprtsec = cl_init->xprtsec;
+	nfs_probe_local_addr(clp);
 	return clp;
 
 error_cleanup:
@@ -236,10 +238,19 @@ static void pnfs_init_server(struct nfs_server *server)
  */
 void nfs_free_client(struct nfs_client *clp)
 {
+	struct nfs_local_addr *addr, *tmp;
+
+	nfs_local_disable(clp);
+
 	/* -EIO all pending I/O */
 	if (!IS_ERR(clp->cl_rpcclient))
 		rpc_shutdown_client(clp->cl_rpcclient);
 
+	list_for_each_entry_safe(addr, tmp, &clp->cl_local_addrs, cl_addrs) {
+		list_del(&addr->cl_addrs);
+		kfree(addr);
+	}
+
 	put_net(clp->cl_net);
 	put_nfs_version(clp->cl_nfs_mod);
 	kfree(clp->cl_hostname);
@@ -427,6 +438,7 @@ struct nfs_client *nfs_get_client(const struct nfs_client_initdata *cl_init)
 			list_add_tail(&new->cl_share_link,
 					&nn->nfs_client_list);
 			spin_unlock(&nn->nfs_client_lock);
+			nfs_local_probe(new);
 			return rpc_ops->init_client(new, cl_init);
 		}
 
diff --git a/fs/nfs/filelayout/filelayout.c b/fs/nfs/filelayout/filelayout.c
index d66f2efbd92f..bd8c717c31d2 100644
--- a/fs/nfs/filelayout/filelayout.c
+++ b/fs/nfs/filelayout/filelayout.c
@@ -489,7 +489,7 @@ filelayout_read_pagelist(struct nfs_pageio_descriptor *desc,
 	/* Perform an asynchronous read to ds */
 	nfs_initiate_pgio(desc, ds->ds_clp, ds_clnt, hdr, hdr->cred,
 			  NFS_PROTO(hdr->inode), &filelayout_read_call_ops,
-			  0, RPC_TASK_SOFTCONN);
+			  0, RPC_TASK_SOFTCONN, NULL);
 	return PNFS_ATTEMPTED;
 }
 
@@ -532,7 +532,7 @@ filelayout_write_pagelist(struct nfs_pageio_descriptor *desc,
 	/* Perform an asynchronous write */
 	nfs_initiate_pgio(desc, ds->ds_clp, ds_clnt, hdr, hdr->cred,
 			  NFS_PROTO(hdr->inode), &filelayout_write_call_ops,
-			  sync, RPC_TASK_SOFTCONN);
+			  sync, RPC_TASK_SOFTCONN, NULL);
 	return PNFS_ATTEMPTED;
 }
 
@@ -1014,7 +1014,7 @@ static int filelayout_initiate_commit(struct nfs_commit_data *data, int how)
 	return nfs_initiate_commit(ds->ds_clp, ds_clnt, data,
 				   NFS_PROTO(data->inode),
 				   &filelayout_commit_call_ops, how,
-				   RPC_TASK_SOFTCONN);
+				   RPC_TASK_SOFTCONN, NULL);
 out_err:
 	pnfs_generic_prepare_to_resend_writes(data);
 	pnfs_generic_commit_release(data);
diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index d7e9e5ef4085..ce6cb5d82427 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -1808,7 +1808,7 @@ ff_layout_read_pagelist(struct nfs_pageio_descriptor *desc,
 			  ds->ds_clp->rpc_ops,
 			  vers == 3 ? &ff_layout_read_call_ops_v3 :
 				      &ff_layout_read_call_ops_v4,
-			  0, RPC_TASK_SOFTCONN);
+			  0, RPC_TASK_SOFTCONN, NULL);
 	put_cred(ds_cred);
 	return PNFS_ATTEMPTED;
 
@@ -1878,7 +1878,7 @@ ff_layout_write_pagelist(struct nfs_pageio_descriptor *desc,
 			  ds->ds_clp->rpc_ops,
 			  vers == 3 ? &ff_layout_write_call_ops_v3 :
 				      &ff_layout_write_call_ops_v4,
-			  sync, RPC_TASK_SOFTCONN);
+			  sync, RPC_TASK_SOFTCONN, NULL);
 	put_cred(ds_cred);
 	return PNFS_ATTEMPTED;
 
@@ -1953,7 +1953,7 @@ static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
 	ret = nfs_initiate_commit(ds->ds_clp, ds_clnt, data, ds->ds_clp->rpc_ops,
 				   vers == 3 ? &ff_layout_commit_call_ops_v3 :
 					       &ff_layout_commit_call_ops_v4,
-				   how, RPC_TASK_SOFTCONN);
+				   how, RPC_TASK_SOFTCONN, NULL);
 	put_cred(ds_cred);
 	return ret;
 out_err:
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index acef52ecb1bb..4f88b860494f 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -39,6 +39,7 @@
 #include <linux/slab.h>
 #include <linux/compat.h>
 #include <linux/freezer.h>
+#include <linux/file.h>
 #include <linux/uaccess.h>
 #include <linux/iversion.h>
 
@@ -1053,6 +1054,7 @@ struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry,
 	ctx->lock_context.open_context = ctx;
 	INIT_LIST_HEAD(&ctx->list);
 	ctx->mdsthreshold = NULL;
+	ctx->local_filp = NULL;
 	return ctx;
 }
 EXPORT_SYMBOL_GPL(alloc_nfs_open_context);
@@ -1084,6 +1086,8 @@ static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
 	nfs_sb_deactive(sb);
 	put_rpccred(rcu_dereference_protected(ctx->ll_cred, 1));
 	kfree(ctx->mdsthreshold);
+	if (!IS_ERR_OR_NULL(ctx->local_filp))
+		fput(ctx->local_filp);
 	kfree_rcu(ctx, rcu_head);
 }
 
@@ -2495,6 +2499,7 @@ static int __init init_nfs_fs(void)
 	if (err)
 		goto out1;
 
+	nfs_local_init();
 	err = register_nfs_fs();
 	if (err)
 		goto out0;
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 873c2339b78a..67b348447a40 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -204,6 +204,12 @@ struct nfs_mount_request {
 	struct net		*net;
 };
 
+struct nfs_local_addr {
+	struct list_head	cl_addrs;
+	struct sockaddr_storage	address;
+	size_t			addrlen;
+};
+
 extern int nfs_mount(struct nfs_mount_request *info, int timeo, int retrans);
 extern void nfs_umount(const struct nfs_mount_request *info);
 
@@ -309,7 +315,8 @@ int nfs_generic_pgio(struct nfs_pageio_descriptor *, struct nfs_pgio_header *);
 int nfs_initiate_pgio(struct nfs_pageio_descriptor *, struct nfs_client *clp,
 		      struct rpc_clnt *rpc_clnt, struct nfs_pgio_header *hdr,
 		      const struct cred *cred, const struct nfs_rpc_ops *rpc_ops,
-		      const struct rpc_call_ops *call_ops, int how, int flags);
+		      const struct rpc_call_ops *call_ops, int how, int flags,
+		      struct file *localio);
 void nfs_free_request(struct nfs_page *req);
 struct nfs_pgio_mirror *
 nfs_pgio_current_mirror(struct nfs_pageio_descriptor *desc);
@@ -450,6 +457,26 @@ extern void nfs_set_cache_invalid(struct inode *inode, unsigned long flags);
 extern bool nfs_check_cache_invalid(struct inode *, unsigned long);
 extern int nfs_wait_bit_killable(struct wait_bit_key *key, int mode);
 
+/* localio.c */
+extern void nfs_local_init(void);
+extern void nfs_local_enable(struct nfs_client *);
+extern void nfs_local_disable(struct nfs_client *);
+extern void nfs_local_probe(struct nfs_client *);
+extern struct file *nfs_local_open_fh(struct nfs_client *, const struct cred *,
+				      struct nfs_fh *, const fmode_t);
+extern struct file *nfs_local_file_open(struct nfs_client *clp,
+					const struct cred *cred,
+					struct nfs_fh *fh,
+					struct nfs_open_context *ctx);
+extern int nfs_local_doio(struct nfs_client *, struct file *,
+			  struct nfs_pgio_header *,
+			  const struct rpc_call_ops *);
+extern int nfs_local_commit(struct nfs_client *, struct file *,
+			    struct nfs_commit_data *,
+			    const struct rpc_call_ops *, int);
+extern void nfs_probe_local_addr(struct nfs_client *clnt);
+extern bool nfs_server_is_local(const struct nfs_client *clp);
+
 /* super.c */
 extern const struct super_operations nfs_sops;
 bool nfs_auth_info_match(const struct nfs_auth_info *, rpc_authflavor_t);
@@ -530,7 +557,8 @@ extern int nfs_initiate_commit(struct nfs_client *clp,
 			       struct nfs_commit_data *data,
 			       const struct nfs_rpc_ops *nfs_ops,
 			       const struct rpc_call_ops *call_ops,
-			       int how, int flags);
+			       int how, int flags,
+			       struct file *localio);
 extern void nfs_init_commit(struct nfs_commit_data *data,
 			    struct list_head *head,
 			    struct pnfs_layout_segment *lseg,
diff --git a/fs/nfs/localio.c b/fs/nfs/localio.c
new file mode 100644
index 000000000000..5c69eb0fe7b6
--- /dev/null
+++ b/fs/nfs/localio.c
@@ -0,0 +1,933 @@
+/*
+ *  linux/fs/nfs/localio.c
+ *
+ *  Copyright (C) 2014  Weston Andros Adamson <dros@primarydata.com>
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/vfs.h>
+#include <linux/file.h>
+#include <linux/inet.h>
+#include <linux/sunrpc/addr.h>
+#include <linux/inetdevice.h>
+#include <net/addrconf.h>
+#include <linux/module.h>
+#include <linux/bvec.h>
+
+#include <linux/nfs.h>
+#include <linux/nfs_fs.h>
+#include <linux/nfs_xdr.h>
+
+#include <uapi/linux/if_arp.h>
+
+#include "internal.h"
+#include "pnfs.h"
+#include "nfstrace.h"
+
+#define NFSDBG_FACILITY		NFSDBG_VFS
+
+extern int nfsd_open_local_fh(struct rpc_clnt *rpc_clnt,
+			      const struct cred *cred,
+			      const struct nfs_fh *nfs_fh, const fmode_t fmode,
+			      struct file **pfilp);
+/*
+ * The localio code needs to call into nfsd to do the filehandle -> struct path
+ * mapping, but cannot be statically linked, because that will make the nfs
+ * module depend on the nfsd module.
+ *
+ * Instead, do dynamic linking to the nfsd module. This way the nfs module
+ * will only hold a reference on nfsd when it's actually in use. This also
+ * allows some sanity checking, like giving up on localio if nfsd isn't loaded.
+ */
+
+struct nfs_local_open_ctx {
+	spinlock_t lock;
+	nfs_to_nfsd_open_t open_f;
+	atomic_t refcount;
+};
+
+struct nfs_local_kiocb {
+	struct kiocb		kiocb;
+	struct bio_vec		*bvec;
+	struct nfs_pgio_header	*hdr;
+	struct work_struct	work;
+};
+
+struct nfs_local_fsync_ctx {
+	struct file		*filp;
+	struct nfs_commit_data	*data;
+	struct work_struct	work;
+	struct kref		kref;
+};
+static void nfs_local_fsync_work(struct work_struct *work);
+
+/*
+ * We need to translate between nfs status return values and
+ * the local errno values which may not be the same.
+ */
+static struct {
+	__u32 stat;
+	int errno;
+} nfs_errtbl[] = {
+	{ NFS4_OK,		0		},
+	{ NFS4ERR_PERM,		-EPERM		},
+	{ NFS4ERR_NOENT,	-ENOENT		},
+	{ NFS4ERR_IO,		-EIO		},
+	{ NFS4ERR_NXIO,		-ENXIO		},
+	{ NFS4ERR_FBIG,		-E2BIG		},
+	{ NFS4ERR_STALE,	-EBADF		},
+	{ NFS4ERR_ACCESS,	-EACCES		},
+	{ NFS4ERR_EXIST,	-EEXIST		},
+	{ NFS4ERR_XDEV,		-EXDEV		},
+	{ NFS4ERR_MLINK,	-EMLINK		},
+	{ NFS4ERR_NOTDIR,	-ENOTDIR	},
+	{ NFS4ERR_ISDIR,	-EISDIR		},
+	{ NFS4ERR_INVAL,	-EINVAL		},
+	{ NFS4ERR_FBIG,		-EFBIG		},
+	{ NFS4ERR_NOSPC,	-ENOSPC		},
+	{ NFS4ERR_ROFS,		-EROFS		},
+	{ NFS4ERR_NAMETOOLONG,	-ENAMETOOLONG	},
+	{ NFS4ERR_NOTEMPTY,	-ENOTEMPTY	},
+	{ NFS4ERR_DQUOT,	-EDQUOT		},
+	{ NFS4ERR_STALE,	-ESTALE		},
+	{ NFS4ERR_STALE,	-EOPENSTALE	},
+	{ NFS4ERR_DELAY,	-ETIMEDOUT	},
+	{ NFS4ERR_DELAY,	-ERESTARTSYS	},
+	{ NFS4ERR_DELAY,	-EAGAIN		},
+	{ NFS4ERR_DELAY,	-ENOMEM		},
+	{ NFS4ERR_IO,		-ETXTBSY	},
+	{ NFS4ERR_IO,		-EBUSY		},
+	{ NFS4ERR_BADHANDLE,	-EBADHANDLE	},
+	{ NFS4ERR_BAD_COOKIE,	-EBADCOOKIE	},
+	{ NFS4ERR_NOTSUPP,	-EOPNOTSUPP	},
+	{ NFS4ERR_TOOSMALL,	-ETOOSMALL	},
+	{ NFS4ERR_SERVERFAULT,	-ESERVERFAULT	},
+	{ NFS4ERR_SERVERFAULT,	-ENFILE		},
+	{ NFS4ERR_IO,		-EREMOTEIO	},
+	{ NFS4ERR_IO,		-EUCLEAN	},
+	{ NFS4ERR_PERM,		-ENOKEY		},
+	{ NFS4ERR_BADTYPE,	-EBADTYPE	},
+	{ NFS4ERR_SYMLINK,	-ELOOP		},
+	{ NFS4ERR_DEADLOCK,	-EDEADLK	},
+};
+
+/*
+ * Convert an NFS error code to a local one.
+ * This one is used jointly by NFSv2 and NFSv3.
+ */
+static __u32
+nfs4errno(int errno)
+{
+	unsigned int i;
+	for (i = 0; i < ARRAY_SIZE(nfs_errtbl); i++) {
+		if (nfs_errtbl[i].errno == errno)
+			return nfs_errtbl[i].stat;
+	}
+	/* If we cannot translate the error, the recovery routines should
+	 * handle it.
+	 * Note: remaining NFSv4 error codes have values > 10000, so should
+	 * not conflict with native Linux error codes.
+	 */
+	return NFS4ERR_SERVERFAULT;
+}
+
+static struct nfs_local_open_ctx __local_open_ctx __read_mostly;
+
+static bool localio_enabled __read_mostly = true;
+module_param(localio_enabled, bool, 0644);
+
+bool nfs_server_is_local(const struct nfs_client *clp)
+{
+	return test_bit(NFS_CS_LOCAL_IO, &clp->cl_flags) != 0 &&
+		localio_enabled;
+}
+EXPORT_SYMBOL_GPL(nfs_server_is_local);
+
+void
+nfs_local_init(void)
+{
+	struct nfs_local_open_ctx *ctx = &__local_open_ctx;
+
+	ctx->open_f = NULL;
+	spin_lock_init(&ctx->lock);
+	atomic_set(&ctx->refcount, 0);
+}
+
+static bool
+nfs_local_get_lookup_ctx(void)
+{
+	struct nfs_local_open_ctx *ctx = &__local_open_ctx;
+	nfs_to_nfsd_open_t fn = NULL;
+
+	spin_lock(&ctx->lock);
+	if (ctx->open_f == NULL) {
+		spin_unlock(&ctx->lock);
+
+		fn = symbol_request(nfsd_open_local_fh);
+		if (!fn)
+			return false;
+
+		spin_lock(&ctx->lock);
+		/* catch race */
+		if (ctx->open_f == NULL) {
+			ctx->open_f = fn;
+			fn = NULL;
+		}
+	}
+	atomic_inc(&ctx->refcount);
+	spin_unlock(&ctx->lock);
+	if (fn)
+		symbol_put(nfsd_open_local_fh);
+	return true;
+}
+
+static void
+nfs_local_put_lookup_ctx(void)
+{
+	struct nfs_local_open_ctx *ctx = &__local_open_ctx;
+	nfs_to_nfsd_open_t fn;
+
+	if (atomic_dec_and_lock(&ctx->refcount, &ctx->lock)) {
+		fn = ctx->open_f;
+		ctx->open_f = NULL;
+		spin_unlock(&ctx->lock);
+		if (fn)
+			symbol_put(nfsd_open_local_fh);
+		dprintk("destroy lookup context\n");
+	}
+}
+
+/*
+ * nfs_local_enable - attempt to enable local i/o for an nfs_client
+ */
+void
+nfs_local_enable(struct nfs_client *clp)
+{
+	if (nfs_local_get_lookup_ctx()) {
+		dprintk("enabled local i/o\n");
+		set_bit(NFS_CS_LOCAL_IO, &clp->cl_flags);
+	}
+}
+EXPORT_SYMBOL_GPL(nfs_local_enable);
+
+/*
+ * nfs_local_disable - disable local i/o for an nfs_client
+ */
+void
+nfs_local_disable(struct nfs_client *clp)
+{
+	if (test_and_clear_bit(NFS_CS_LOCAL_IO, &clp->cl_flags)) {
+		dprintk("disabled local i/o\n");
+		nfs_local_put_lookup_ctx();
+	}
+}
+
+/*
+ * nfs_local_probe - probe local i/o support for an nfs_client
+ */
+void
+nfs_local_probe(struct nfs_client *clp)
+{
+	struct sockaddr_in *sin;
+	struct sockaddr_in6 *sin6;
+	struct nfs_local_addr *addr;
+	struct sockaddr *sap;
+	bool enable = false;
+
+	switch (clp->cl_addr.ss_family) {
+	case AF_INET:
+		sin = (struct sockaddr_in *)&clp->cl_addr;
+		if (ipv4_is_loopback(sin->sin_addr.s_addr)) {
+			dprintk("%s: detected IPv4 loopback address\n",
+				__func__);
+			enable = true;
+		}
+		break;
+	case AF_INET6:
+		sin6 = (struct sockaddr_in6 *)&clp->cl_addr;
+		if (memcmp(&sin6->sin6_addr, &in6addr_loopback,
+		    sizeof(struct in6_addr)) == 0) {
+			dprintk("%s: detected IPv6 loopback address\n",
+				__func__);
+			enable = true;
+		}
+		break;
+	default:
+		break;
+	}
+
+	if (enable)
+		goto out;
+
+	list_for_each_entry(addr, &clp->cl_local_addrs, cl_addrs) {
+		sap = (struct sockaddr *)&addr->address;
+		if (rpc_cmp_addr((struct sockaddr *)&clp->cl_addr, sap)) {
+			dprintk("%s: detected local server.\n", __func__);
+			enable = true;
+			break;
+		}
+	}
+
+out:
+	if (enable)
+		nfs_local_enable(clp);
+}
+
+/*
+ * nfs_local_open_fh - open a local filehandle
+ *
+ * Returns a pointer to a struct file or an ERR_PTR
+ */
+struct file *
+nfs_local_open_fh(struct nfs_client *clp, const struct cred *cred,
+		  struct nfs_fh *fh, const fmode_t mode)
+{
+	struct nfs_local_open_ctx *ctx = &__local_open_ctx;
+	struct file *filp;
+	int status;
+
+	if (mode & ~(FMODE_READ | FMODE_WRITE))
+		return ERR_PTR(-EINVAL);
+
+	status = ctx->open_f(clp->cl_rpcclient, cred, fh, mode, &filp);
+	if (status < 0) {
+		dprintk("%s: open local file failed error=%d\n",
+				__func__, status);
+		trace_nfs_local_open_fh(fh, mode, status);
+		switch (status) {
+		case -ENXIO:
+			nfs_local_disable(clp);
+			fallthrough;
+		case -ETIMEDOUT:
+			status = -EAGAIN;
+		}
+		filp = ERR_PTR(status);
+	}
+	return filp;
+}
+EXPORT_SYMBOL_GPL(nfs_local_open_fh);
+
+static struct bio_vec *
+nfs_bvec_alloc_and_import_pagevec(struct page **pagevec,
+		unsigned int npages, gfp_t flags)
+{
+	struct bio_vec *bvec, *p;
+
+	bvec = kmalloc_array(npages, sizeof(*bvec), flags);
+	if (bvec != NULL) {
+		for (p = bvec; npages > 0; p++, pagevec++, npages--) {
+			p->bv_page = *pagevec;
+			p->bv_len = PAGE_SIZE;
+			p->bv_offset = 0;
+		}
+	}
+	return bvec;
+}
+
+static void
+nfs_local_iocb_free(struct nfs_local_kiocb *iocb)
+{
+	kfree(iocb->bvec);
+	kfree(iocb);
+}
+
+static struct nfs_local_kiocb *
+nfs_local_iocb_alloc(struct nfs_pgio_header *hdr, struct file *filp,
+		gfp_t flags)
+{
+	struct nfs_local_kiocb *iocb;
+
+	iocb = kmalloc(sizeof(*iocb), flags);
+	if (iocb == NULL)
+		return NULL;
+	iocb->bvec = nfs_bvec_alloc_and_import_pagevec(hdr->page_array.pagevec,
+			hdr->page_array.npages, flags);
+	if (iocb->bvec == NULL) {
+		kfree(iocb);
+		return NULL;
+	}
+	init_sync_kiocb(&iocb->kiocb, filp);
+	iocb->kiocb.ki_pos = hdr->args.offset;
+	iocb->hdr = hdr;
+	/* FIXME: NFS_IOHDR_ODIRECT isn't ever set */
+	if (test_bit(NFS_IOHDR_ODIRECT, &hdr->flags))
+		iocb->kiocb.ki_flags |= IOCB_DIRECT|IOCB_DSYNC;
+	iocb->kiocb.ki_flags &= ~IOCB_APPEND;
+	return iocb;
+}
+
+static void
+nfs_local_iter_init(struct iov_iter *i, struct nfs_local_kiocb *iocb, int dir)
+{
+	struct nfs_pgio_header *hdr = iocb->hdr;
+
+	if (hdr->args.pgbase != 0) {
+		iov_iter_bvec(i, dir, iocb->bvec,
+				hdr->page_array.npages,
+				hdr->args.count + hdr->args.pgbase);
+		iov_iter_advance(i, hdr->args.pgbase);
+	} else
+		iov_iter_bvec(i, dir, iocb->bvec,
+				hdr->page_array.npages, hdr->args.count);
+}
+
+static void
+nfs_local_hdr_release(struct nfs_pgio_header *hdr,
+		const struct rpc_call_ops *call_ops)
+{
+	call_ops->rpc_call_done(&hdr->task, hdr);
+	call_ops->rpc_release(hdr);
+}
+
+static void
+nfs_local_pgio_init(struct nfs_pgio_header *hdr,
+		const struct rpc_call_ops *call_ops)
+{
+	hdr->task.tk_ops = call_ops;
+	if (!hdr->task.tk_start)
+		hdr->task.tk_start = ktime_get();
+}
+
+static void
+nfs_local_pgio_done(struct nfs_pgio_header *hdr, long status)
+{
+	if (status >= 0) {
+		hdr->res.count = status;
+		hdr->res.op_status = NFS4_OK;
+		hdr->task.tk_status = 0;
+	} else {
+		hdr->res.op_status = nfs4errno(status);
+		hdr->task.tk_status = status;
+	}
+}
+
+static void
+nfs_local_pgio_release(struct nfs_local_kiocb *iocb)
+{
+	struct nfs_pgio_header *hdr = iocb->hdr;
+
+	fput(iocb->kiocb.ki_filp);
+	nfs_local_iocb_free(iocb);
+	nfs_local_hdr_release(hdr, hdr->task.tk_ops);
+}
+
+static void
+nfs_local_read_aio_complete_work(struct work_struct *work)
+{
+	struct nfs_local_kiocb *iocb = container_of(work,
+			struct nfs_local_kiocb, work);
+
+	nfs_local_pgio_release(iocb);
+}
+
+/*
+ * Complete the I/O from iocb->kiocb.ki_complete()
+ *
+ * Note that this function can be called from a bottom half context,
+ * hence we need to queue the fput() etc to a workqueue
+ */
+static void
+nfs_local_pgio_complete(struct nfs_local_kiocb *iocb)
+{
+	queue_work(nfsiod_workqueue, &iocb->work);
+}
+
+static void
+nfs_local_read_done(struct nfs_local_kiocb *iocb, long status)
+{
+	struct nfs_pgio_header *hdr = iocb->hdr;
+	struct file *filp = iocb->kiocb.ki_filp;
+
+	nfs_local_pgio_done(hdr, status);
+
+	if (hdr->res.count != hdr->args.count ||
+	    hdr->args.offset + hdr->res.count >= i_size_read(file_inode(filp)))
+		hdr->res.eof = true;
+
+	dprintk("%s: read %ld bytes eof %d.\n", __func__,
+			status > 0 ? status : 0, hdr->res.eof);
+}
+
+static void
+nfs_local_read_aio_complete(struct kiocb *kiocb, long ret)
+{
+	struct nfs_local_kiocb *iocb = container_of(kiocb,
+			struct nfs_local_kiocb, kiocb);
+
+	nfs_local_read_done(iocb, ret);
+	nfs_local_pgio_complete(iocb);
+}
+
+static int
+nfs_do_local_read(struct nfs_pgio_header *hdr, struct file *filp,
+		const struct rpc_call_ops *call_ops)
+{
+	struct nfs_local_kiocb *iocb;
+	struct iov_iter iter;
+	ssize_t status;
+
+	dprintk("%s: vfs_read count=%u pos=%llu\n",
+		__func__, hdr->args.count, hdr->args.offset);
+
+	iocb = nfs_local_iocb_alloc(hdr, filp, GFP_KERNEL);
+	if (iocb == NULL)
+		return -ENOMEM;
+	nfs_local_iter_init(&iter, iocb, READ);
+
+	nfs_local_pgio_init(hdr, call_ops);
+	hdr->res.eof = false;
+
+	if (iocb->kiocb.ki_flags & IOCB_DIRECT) {
+		INIT_WORK(&iocb->work, nfs_local_read_aio_complete_work);
+		iocb->kiocb.ki_complete = nfs_local_read_aio_complete;
+	}
+
+	status = filp->f_op->read_iter(&iocb->kiocb, &iter);
+	if (status != -EIOCBQUEUED) {
+		nfs_local_read_done(iocb, status);
+		nfs_local_pgio_release(iocb);
+	}
+	return 0;
+}
+
+static void
+nfs_copy_boot_verifier(struct nfs_write_verifier *verifier, struct inode *inode)
+{
+	struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
+	u32 *verf = (u32 *)verifier->data;
+	int seq = 0;
+
+	do {
+		read_seqbegin_or_lock(&clp->cl_boot_lock, &seq);
+		verf[0] = (u32)clp->cl_nfssvc_boot.tv_sec;
+		verf[1] = (u32)clp->cl_nfssvc_boot.tv_nsec;
+	} while (need_seqretry(&clp->cl_boot_lock, seq));
+	done_seqretry(&clp->cl_boot_lock, seq);
+}
+
+static void
+nfs_reset_boot_verifier(struct inode *inode)
+{
+	struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
+
+	write_seqlock(&clp->cl_boot_lock);
+	ktime_get_real_ts64(&clp->cl_nfssvc_boot);
+	write_sequnlock(&clp->cl_boot_lock);
+}
+
+static void
+nfs_set_local_verifier(struct inode *inode,
+		struct nfs_writeverf *verf,
+		enum nfs3_stable_how how)
+{
+
+	nfs_copy_boot_verifier(&verf->verifier, inode);
+	verf->committed = how;
+}
+
+static void
+nfs_get_vfs_attr(struct file *filp, struct nfs_fattr *fattr)
+{
+	struct kstat stat;
+
+	if (fattr != NULL && vfs_getattr(&filp->f_path, &stat,
+					 STATX_INO |
+					 STATX_ATIME |
+					 STATX_MTIME |
+					 STATX_CTIME |
+					 STATX_SIZE |
+					 STATX_BLOCKS,
+					 AT_STATX_SYNC_AS_STAT) == 0) {
+		fattr->valid = NFS_ATTR_FATTR_FILEID |
+			NFS_ATTR_FATTR_CHANGE |
+			NFS_ATTR_FATTR_SIZE |
+			NFS_ATTR_FATTR_ATIME |
+			NFS_ATTR_FATTR_MTIME |
+			NFS_ATTR_FATTR_CTIME |
+			NFS_ATTR_FATTR_SPACE_USED;
+		fattr->fileid = stat.ino;
+		fattr->size = stat.size;
+		fattr->atime = stat.atime;
+		fattr->mtime = stat.mtime;
+		fattr->ctime = stat.ctime;
+		fattr->change_attr = nfs_timespec_to_change_attr(&fattr->ctime);
+		fattr->du.nfs3.used = stat.blocks << 9;
+	}
+}
+
+static void
+nfs_local_write_done(struct nfs_local_kiocb *iocb, long status)
+{
+	struct nfs_pgio_header *hdr = iocb->hdr;
+
+	dprintk("%s: wrote %ld bytes.\n", __func__, status > 0 ? status : 0);
+
+	/* Handle short writes as if they are ENOSPC */
+	if (status > 0 && status < hdr->args.count) {
+		hdr->mds_offset += status;
+		hdr->args.offset += status;
+		hdr->args.pgbase += status;
+		hdr->args.count -= status;
+		nfs_set_pgio_error(hdr, -ENOSPC, hdr->args.offset);
+		status = -ENOSPC;
+	}
+	if (status < 0)
+		nfs_reset_boot_verifier(hdr->inode);
+	nfs_local_pgio_done(hdr, status);
+}
+
+static void
+nfs_local_write_aio_complete_work(struct work_struct *work)
+{
+	struct nfs_local_kiocb *iocb = container_of(work,
+			struct nfs_local_kiocb, work);
+
+	nfs_get_vfs_attr(iocb->kiocb.ki_filp, iocb->hdr->res.fattr);
+	nfs_local_pgio_release(iocb);
+}
+
+static void
+nfs_local_write_aio_complete(struct kiocb *kiocb, long ret)
+{
+	struct nfs_local_kiocb *iocb = container_of(kiocb,
+			struct nfs_local_kiocb, kiocb);
+
+	nfs_local_write_done(iocb, ret);
+	nfs_local_pgio_complete(iocb);
+}
+
+static int
+nfs_do_local_write(struct nfs_pgio_header *hdr, struct file *filp,
+		const struct rpc_call_ops *call_ops)
+{
+	struct nfs_local_kiocb *iocb;
+	struct iov_iter iter;
+	ssize_t status;
+
+	dprintk("%s: vfs_write count=%u pos=%llu %s\n",
+		__func__, hdr->args.count, hdr->args.offset,
+		(hdr->args.stable == NFS_UNSTABLE) ?  "unstable" : "stable");
+
+	iocb = nfs_local_iocb_alloc(hdr, filp, GFP_NOIO);
+	if (iocb == NULL)
+		return -ENOMEM;
+	nfs_local_iter_init(&iter, iocb, WRITE);
+
+	switch (hdr->args.stable) {
+	default:
+		break;
+	case NFS_DATA_SYNC:
+		iocb->kiocb.ki_flags |= IOCB_DSYNC;
+		break;
+	case NFS_FILE_SYNC:
+		iocb->kiocb.ki_flags |= IOCB_DSYNC|IOCB_SYNC;
+	}
+	nfs_local_pgio_init(hdr, call_ops);
+
+	if (iocb->kiocb.ki_flags & IOCB_DIRECT) {
+		INIT_WORK(&iocb->work, nfs_local_write_aio_complete_work);
+		iocb->kiocb.ki_complete = nfs_local_write_aio_complete;
+	}
+
+	nfs_set_local_verifier(hdr->inode, hdr->res.verf, hdr->args.stable);
+
+	file_start_write(filp);
+	status = filp->f_op->write_iter(&iocb->kiocb, &iter);
+	file_end_write(filp);
+	if (status != -EIOCBQUEUED) {
+		nfs_local_write_done(iocb, status);
+		nfs_get_vfs_attr(filp, hdr->res.fattr);
+		nfs_local_pgio_release(iocb);
+	}
+	return 0;
+}
+
+static struct file *
+nfs_local_file_open_cached(struct nfs_client *clp, const struct cred *cred,
+			   struct nfs_fh *fh, struct nfs_open_context *ctx)
+{
+	struct file *filp = ctx->local_filp;
+
+	if (!filp) {
+		struct file *new = nfs_local_open_fh(clp, cred, fh, ctx->mode);
+		if (IS_ERR_OR_NULL(new))
+			return NULL;
+		/* try to put this one in the slot */
+		filp = cmpxchg(&ctx->local_filp, NULL, new);
+		if (filp != NULL)
+			fput(new);
+		else
+			filp = new;
+	}
+	return get_file(filp);
+}
+
+struct file *
+nfs_local_file_open(struct nfs_client *clp, const struct cred *cred,
+		    struct nfs_fh *fh, struct nfs_open_context *ctx)
+{
+	if (!nfs_server_is_local(clp))
+		return NULL;
+	return nfs_local_file_open_cached(clp, cred, fh, ctx);
+}
+
+int
+nfs_local_doio(struct nfs_client *clp, struct file *filp,
+	       struct nfs_pgio_header *hdr,
+	       const struct rpc_call_ops *call_ops)
+{
+	int status = 0;
+
+	if (!hdr->args.count)
+		goto out_fput;
+	/* Don't support filesystems without read_iter/write_iter */
+	if (!filp->f_op->read_iter || !filp->f_op->write_iter) {
+		nfs_local_disable(clp);
+		status = -EAGAIN;
+		goto out_fput;
+	}
+
+	switch (hdr->rw_mode) {
+	case FMODE_READ:
+		status = nfs_do_local_read(hdr, filp, call_ops);
+		break;
+	case FMODE_WRITE:
+		status = nfs_do_local_write(hdr, filp, call_ops);
+		break;
+	default:
+		dprintk("%s: invalid mode: %d\n", __func__,
+			hdr->rw_mode);
+		status = -EINVAL;
+	}
+out_fput:
+	if (status != 0) {
+		fput(filp);
+		hdr->task.tk_status = status;
+		nfs_local_hdr_release(hdr, call_ops);
+	}
+	return status;
+}
+
+static void
+nfs_local_init_commit(struct nfs_commit_data *data,
+		const struct rpc_call_ops *call_ops)
+{
+	data->task.tk_ops = call_ops;
+}
+
+static int
+nfs_local_run_commit(struct file *filp, struct nfs_commit_data *data)
+{
+	loff_t start = data->args.offset;
+	loff_t end = LLONG_MAX;
+
+	if (data->args.count > 0) {
+		end = start + data->args.count - 1;
+		if (end < start)
+			end = LLONG_MAX;
+	}
+
+	dprintk("%s: commit %llu - %llu\n", __func__, start, end);
+	return vfs_fsync_range(filp, start, end, 0);
+}
+
+static void
+nfs_local_commit_done(struct nfs_commit_data *data, int status)
+{
+	if (status >= 0) {
+		nfs_set_local_verifier(data->inode,
+				data->res.verf,
+				NFS_FILE_SYNC);
+		data->res.op_status = NFS4_OK;
+		data->task.tk_status = 0;
+	} else {
+		nfs_reset_boot_verifier(data->inode);
+		data->res.op_status = nfs4errno(status);
+		data->task.tk_status = status;
+	}
+}
+
+static void
+nfs_local_release_commit_data(struct file *filp,
+		struct nfs_commit_data *data,
+		const struct rpc_call_ops *call_ops)
+{
+	fput(filp);
+	call_ops->rpc_call_done(&data->task, data);
+	call_ops->rpc_release(data);
+}
+
+static struct nfs_local_fsync_ctx *
+nfs_local_fsync_ctx_alloc(struct nfs_commit_data *data, struct file *filp,
+		gfp_t flags)
+{
+	struct nfs_local_fsync_ctx *ctx = kmalloc(sizeof(*ctx), flags);
+
+	if (ctx != NULL) {
+		ctx->filp = filp;
+		ctx->data = data;
+		INIT_WORK(&ctx->work, nfs_local_fsync_work);
+		kref_init(&ctx->kref);
+	}
+	return ctx;
+}
+
+static void
+nfs_local_fsync_ctx_kref_free(struct kref *kref)
+{
+	kfree(container_of(kref, struct nfs_local_fsync_ctx, kref));
+}
+
+static void
+nfs_local_fsync_ctx_put(struct nfs_local_fsync_ctx *ctx)
+{
+	kref_put(&ctx->kref, nfs_local_fsync_ctx_kref_free);
+}
+
+static void
+nfs_local_fsync_ctx_free(struct nfs_local_fsync_ctx *ctx)
+{
+	nfs_local_release_commit_data(ctx->filp, ctx->data,
+			ctx->data->task.tk_ops);
+	nfs_local_fsync_ctx_put(ctx);
+}
+
+static void
+nfs_local_fsync_work(struct work_struct *work)
+{
+	struct nfs_local_fsync_ctx *ctx;
+	int status;
+
+	ctx = container_of(work, struct nfs_local_fsync_ctx, work);
+
+	status = nfs_local_run_commit(ctx->filp, ctx->data);
+	nfs_local_commit_done(ctx->data, status);
+	nfs_local_fsync_ctx_free(ctx);
+}
+
+int
+nfs_local_commit(struct nfs_client *clp, struct file *filp,
+		 struct nfs_commit_data *data,
+		 const struct rpc_call_ops *call_ops, int how)
+{
+	struct nfs_local_fsync_ctx *ctx;
+
+	ctx = nfs_local_fsync_ctx_alloc(data, filp, GFP_KERNEL);
+	if (!ctx) {
+		nfs_local_commit_done(data, -ENOMEM);
+		nfs_local_release_commit_data(filp, data, call_ops);
+		return -ENOMEM;
+	}
+
+	nfs_local_init_commit(data, call_ops);
+	kref_get(&ctx->kref);
+	queue_work(nfsiod_workqueue, &ctx->work);
+	if (how & FLUSH_SYNC)
+		flush_work(&ctx->work);
+	nfs_local_fsync_ctx_put(ctx);
+	return 0;
+}
+
+static int
+nfs_client_add_addr(struct nfs_client *clnt, char *buf, gfp_t flags)
+{
+	struct nfs_local_addr *addr;
+	struct sockaddr *sap;
+
+	dprintk("%s: adding new local IP %s\n", __func__, buf);
+	addr = kmalloc(sizeof(*addr), flags);
+	if (!addr) {
+		printk(KERN_WARNING "NFS: cannot alloc new addr\n");
+		return -ENOMEM;
+	}
+	sap = (struct sockaddr *)&addr->address;
+	addr->addrlen = rpc_pton(clnt->cl_net, buf, strlen(buf),
+				sap, sizeof(addr->address));
+	if (!addr->addrlen) {
+		printk(KERN_WARNING "NFS: cannot parse new addr %s\n",
+				buf);
+		kfree(addr);
+		return -EINVAL;
+	}
+	list_add(&addr->cl_addrs, &clnt->cl_local_addrs);
+
+	return 0;
+}
+
+static int
+nfs_client_add_v4_addr(struct nfs_client *clnt, struct in_device *indev,
+		       char *buf, size_t buflen)
+{
+	struct in_ifaddr *ifa;
+	int ret;
+
+	in_dev_for_each_ifa_rtnl(ifa, indev) {
+		snprintf(buf, buflen, "%pI4", &ifa->ifa_local);
+		ret = nfs_client_add_addr(clnt, buf, GFP_KERNEL);
+		if (ret < 0)
+			return ret;
+	}
+
+	return 0;
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static int
+nfs_client_add_v6_addr(struct nfs_client *clnt, struct inet6_dev *in6dev,
+		       char *buf, size_t buflen)
+{
+	struct inet6_ifaddr *ifp;
+	int ret = 0;
+
+	read_lock_bh(&in6dev->lock);
+	list_for_each_entry(ifp, &in6dev->addr_list, if_list) {
+		rpc_ntop6_addr_noscopeid(&ifp->addr, buf, buflen);
+		ret = nfs_client_add_addr(clnt, buf, GFP_ATOMIC);
+		if (ret < 0)
+			goto out;
+	}
+out:
+	read_unlock_bh(&in6dev->lock);
+	return ret;
+}
+#else /* CONFIG_IPV6 */
+static int
+nfs_client_add_v6_addr(struct nfs_client *clnt, struct inet6_dev *in6dev,
+		       char *buf, size_t buflen)
+{
+	return 0;
+}
+#endif
+
+/* Find out all local IP addresses. Ignore errors
+ * because local IO can be optional.
+ */
+void
+nfs_probe_local_addr(struct nfs_client *clnt)
+{
+	struct net_device *dev;
+	struct in_device *indev;
+	struct inet6_dev *in6dev;
+	char buf[INET6_ADDRSTRLEN + IPV6_SCOPE_ID_LEN];
+	size_t buflen = sizeof(buf);
+
+	rtnl_lock();
+
+	for_each_netdev(clnt->cl_net, dev) {
+		if (dev->type == ARPHRD_LOOPBACK ||
+		    !(dev->flags & IFF_UP))
+			continue;
+		indev = __in_dev_get_rtnl(dev);
+		if (indev &&
+		    nfs_client_add_v4_addr(clnt, indev, buf, buflen) < 0)
+			break;
+		in6dev = __in6_dev_get(dev);
+		if (in6dev &&
+		    nfs_client_add_v6_addr(clnt, in6dev, buf, buflen) < 0)
+			break;
+	}
+
+	rtnl_unlock();
+}
diff --git a/fs/nfs/nfstrace.h b/fs/nfs/nfstrace.h
index 1e710654af11..45d4086cdeb1 100644
--- a/fs/nfs/nfstrace.h
+++ b/fs/nfs/nfstrace.h
@@ -1681,6 +1681,35 @@ TRACE_EVENT(nfs_mount_path,
 	TP_printk("path='%s'", __get_str(path))
 );
 
+TRACE_EVENT(nfs_local_open_fh,
+		TP_PROTO(
+			const struct nfs_fh *fh,
+			fmode_t fmode,
+			int error
+		),
+
+		TP_ARGS(fh, fmode, error),
+
+		TP_STRUCT__entry(
+			__field(int, error)
+			__field(u32, fhandle)
+			__field(unsigned int, fmode)
+		),
+
+		TP_fast_assign(
+			__entry->error = error;
+			__entry->fhandle = nfs_fhandle_hash(fh);
+			__entry->fmode = (__force unsigned int)fmode;
+		),
+
+		TP_printk(
+			"error=%d fhandle=0x%08x mode=%s",
+			__entry->error,
+			__entry->fhandle,
+			show_fs_fmode_flags(__entry->fmode)
+		)
+);
+
 DECLARE_EVENT_CLASS(nfs_xdr_event,
 		TP_PROTO(
 			const struct xdr_stream *xdr,
diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 3786d767e2ff..9210a1821ec9 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -848,7 +848,8 @@ int nfs_initiate_pgio(struct nfs_pageio_descriptor *desc,
 		      struct nfs_client *clp, struct rpc_clnt *rpc_clnt,
 		      struct nfs_pgio_header *hdr, const struct cred *cred,
 		      const struct nfs_rpc_ops *rpc_ops,
-		      const struct rpc_call_ops *call_ops, int how, int flags)
+		      const struct rpc_call_ops *call_ops, int how, int flags,
+		      struct file *localio)
 {
 	struct rpc_task *task;
 	struct rpc_message msg = {
@@ -878,10 +879,16 @@ int nfs_initiate_pgio(struct nfs_pageio_descriptor *desc,
 		hdr->args.count,
 		(unsigned long long)hdr->args.offset);
 
+	if (localio) {
+		nfs_local_doio(clp, localio, hdr, call_ops);
+		goto out;
+	}
+
 	task = rpc_run_task(&task_setup_data);
 	if (IS_ERR(task))
 		return PTR_ERR(task);
 	rpc_put_task(task);
+out:
 	return 0;
 }
 EXPORT_SYMBOL_GPL(nfs_initiate_pgio);
@@ -1080,7 +1087,8 @@ static int nfs_generic_pg_pgios(struct nfs_pageio_descriptor *desc)
 					NFS_PROTO(hdr->inode),
 					desc->pg_rpc_callops,
 					desc->pg_ioflags,
-					RPC_TASK_CRED_NOREF | task_flags);
+					RPC_TASK_CRED_NOREF | task_flags,
+					NULL);
 	}
 	return ret;
 }
diff --git a/fs/nfs/pnfs_nfs.c b/fs/nfs/pnfs_nfs.c
index b29b50c2c933..ac3c5e6d4c5e 100644
--- a/fs/nfs/pnfs_nfs.c
+++ b/fs/nfs/pnfs_nfs.c
@@ -538,7 +538,7 @@ pnfs_generic_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
 					    NFS_CLIENT(inode), data,
 					    NFS_PROTO(data->inode),
 					    data->mds_ops, how,
-					    RPC_TASK_CRED_NOREF);
+					    RPC_TASK_CRED_NOREF, NULL);
 		} else {
 			nfs_init_commit(data, NULL, data->lseg, cinfo);
 			initiate_commit(data, how);
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index c9cfa1308264..ba0b36b15bc1 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -1672,7 +1672,8 @@ int nfs_initiate_commit(struct nfs_client *clp,
 			struct nfs_commit_data *data,
 			const struct nfs_rpc_ops *nfs_ops,
 			const struct rpc_call_ops *call_ops,
-			int how, int flags)
+			int how, int flags,
+			struct file *localio)
 {
 	struct rpc_task *task;
 	int priority = flush_task_priority(how);
@@ -1691,6 +1692,7 @@ int nfs_initiate_commit(struct nfs_client *clp,
 		.flags = RPC_TASK_ASYNC | flags,
 		.priority = priority,
 	};
+	int status = 0;
 
 	if (nfs_server_capable(data->inode, NFS_CAP_MOVEABLE))
 		task_setup_data.flags |= RPC_TASK_MOVEABLE;
@@ -1701,13 +1703,19 @@ int nfs_initiate_commit(struct nfs_client *clp,
 
 	dprintk("NFS: initiated commit call\n");
 
+	if (localio) {
+		nfs_local_commit(clp, localio, data, call_ops, how);
+		goto out;
+	}
+
 	task = rpc_run_task(&task_setup_data);
 	if (IS_ERR(task))
 		return PTR_ERR(task);
 	if (how & FLUSH_SYNC)
 		rpc_wait_for_completion_task(task);
 	rpc_put_task(task);
-	return 0;
+out:
+	return status;
 }
 EXPORT_SYMBOL_GPL(nfs_initiate_commit);
 
@@ -1819,7 +1827,7 @@ nfs_commit_list(struct inode *inode, struct list_head *head, int how,
 	return nfs_initiate_commit(NFS_SERVER(inode)->nfs_client,
 				   NFS_CLIENT(inode), data, NFS_PROTO(inode),
 				   data->mds_ops, how,
-				   RPC_TASK_CRED_NOREF | task_flags);
+				   RPC_TASK_CRED_NOREF | task_flags, NULL);
 }
 
 /*
diff --git a/fs/nfsd/Makefile b/fs/nfsd/Makefile
index b8736a82e57c..702f277394f1 100644
--- a/fs/nfsd/Makefile
+++ b/fs/nfsd/Makefile
@@ -13,7 +13,7 @@ nfsd-y			+= trace.o
 nfsd-y 			+= nfssvc.o nfsctl.o nfsfh.o vfs.o \
 			   export.o auth.o lockd.o nfscache.o \
 			   stats.o filecache.o nfs3proc.o nfs3xdr.o \
-			   netlink.o
+			   netlink.o localio.o
 nfsd-$(CONFIG_NFSD_V2) += nfsproc.o nfsxdr.o
 nfsd-$(CONFIG_NFSD_V2_ACL) += nfs2acl.o
 nfsd-$(CONFIG_NFSD_V3_ACL) += nfs3acl.o
diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
index ad9083ca144b..99631fa56662 100644
--- a/fs/nfsd/filecache.c
+++ b/fs/nfsd/filecache.c
@@ -52,7 +52,7 @@
 #define NFSD_FILE_CACHE_UP		     (0)
 
 /* We only care about NFSD_MAY_READ/WRITE for this cache */
-#define NFSD_FILE_MAY_MASK	(NFSD_MAY_READ|NFSD_MAY_WRITE)
+#define NFSD_FILE_MAY_MASK	(NFSD_MAY_READ|NFSD_MAY_WRITE|NFSD_MAY_LOCALIO)
 
 static DEFINE_PER_CPU(unsigned long, nfsd_file_cache_hits);
 static DEFINE_PER_CPU(unsigned long, nfsd_file_acquisitions);
diff --git a/fs/nfsd/localio.c b/fs/nfsd/localio.c
new file mode 100644
index 000000000000..ff68454a4017
--- /dev/null
+++ b/fs/nfsd/localio.c
@@ -0,0 +1,179 @@
+/*
+ * NFS server support for local clients to bypass network stack
+ *
+ * Copyright (C) 2014 Weston Andros Adamson <dros@primarydata.com>
+ */
+
+#include <linux/exportfs.h>
+#include <linux/sunrpc/svcauth_gss.h>
+#include <linux/sunrpc/clnt.h>
+#include <linux/nfs.h>
+#include <linux/string.h>
+
+#include "nfsd.h"
+#include "vfs.h"
+#include "netns.h"
+#include "filecache.h"
+
+#define NFSDDBG_FACILITY		NFSDDBG_FH
+
+static void
+nfsd_local_fakerqst_destroy(struct svc_rqst *rqstp)
+{
+	if (rqstp->rq_client)
+		auth_domain_put(rqstp->rq_client);
+	if (rqstp->rq_cred.cr_group_info)
+		put_group_info(rqstp->rq_cred.cr_group_info);
+	kfree(rqstp->rq_cred.cr_principal);
+	kfree(rqstp->rq_xprt);
+	kfree(rqstp);
+}
+
+static struct svc_rqst *
+nfsd_local_fakerqst_create(struct rpc_clnt *rpc_clnt, const struct cred *cred)
+{
+	struct svc_rqst *rqstp;
+	struct net *net = rpc_net_ns(rpc_clnt);
+	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
+	int status;
+
+	if (!nn->nfsd_serv) {
+		dprintk("%s: localio denied. Server not running\n", __func__);
+		return ERR_PTR(-ENXIO);
+	}
+
+	rqstp = kzalloc(sizeof(*rqstp), GFP_KERNEL);
+	if (!rqstp)
+		return ERR_PTR(-ENOMEM);
+
+	rqstp->rq_xprt = kzalloc(sizeof(*rqstp->rq_xprt), GFP_KERNEL);
+	if (!rqstp->rq_xprt) {
+		status = -ENOMEM;
+		goto out_err;
+	}
+
+	rqstp->rq_xprt->xpt_net = net;
+	__set_bit(RQ_SECURE, &rqstp->rq_flags);
+	rqstp->rq_proc = 1;
+	rqstp->rq_vers = 3;
+	rqstp->rq_prot = IPPROTO_TCP;
+	rqstp->rq_server = nn->nfsd_serv;
+
+	/* Note: we're connecting to ourself, so source addr == peer addr */
+	rqstp->rq_addrlen = rpc_peeraddr(rpc_clnt,
+			(struct sockaddr *)&rqstp->rq_addr,
+			sizeof(rqstp->rq_addr));
+
+	if (!rpcauth_map_to_svc_cred(rpc_clnt->cl_auth, cred,
+				     &rqstp->rq_cred)) {
+		dprintk("%s :map cred failed\n", __func__);
+		status = -EINVAL;
+		goto out_err;
+	}
+
+	/*
+	 * set up enough for svcauth_unix_set_client to be able to wait
+	 * for the cache downcall. Note that we do _not_ want to allow the
+	 * request to be deferred for later revisit since this rqst and xprt
+	 * are not set up to run inside of the normal svc_rqst engine.
+	 */
+	INIT_LIST_HEAD(&rqstp->rq_xprt->xpt_deferred);
+	kref_init(&rqstp->rq_xprt->xpt_ref);
+	spin_lock_init(&rqstp->rq_xprt->xpt_lock);
+	rqstp->rq_chandle.thread_wait = 5 * HZ;
+
+	status = svcauth_unix_set_client(rqstp);
+	switch (status) {
+	case SVC_OK:
+		break;
+	case SVC_DENIED:
+		status = -ENXIO;
+		dprintk("%s: client %pISpc denied localio access\n",
+				__func__, (struct sockaddr *)&rqstp->rq_addr);
+		goto out_err;
+	default:
+		status = -ETIMEDOUT;
+		dprintk("%s: client %pISpc temporarily denied localio access\n",
+				__func__, (struct sockaddr *)&rqstp->rq_addr);
+		goto out_err;
+	}
+
+	return rqstp;
+
+out_err:
+	nfsd_local_fakerqst_destroy(rqstp);
+	return ERR_PTR(status);
+}
+
+/*
+ * nfsd_open_local_fh - lookup a local filehandle @nfs_fh and map to @file
+ *
+ * This function maps a local fh to a path on a local filesystem.
+ * This is useful when the nfs client has the local server mounted - it can
+ * avoid all the NFS overhead with reads, writes and commits.
+ *
+ * on successful return, caller is responsible for calling path_put. Also
+ * note that this is called from nfs.ko via find_symbol() to avoid an explicit
+ * dependency on knfsd. So, there is no forward declaration in a header file
+ * for it.
+ */
+int nfsd_open_local_fh(struct rpc_clnt *rpc_clnt,
+			 const struct cred *cred,
+			 const struct nfs_fh *nfs_fh,
+			 const fmode_t fmode,
+			 struct file **pfilp)
+{
+	const struct cred *save_cred;
+	struct svc_rqst *rqstp;
+	struct svc_fh fh;
+	struct nfsd_file *nf;
+	int status = 0;
+	int mayflags = NFSD_MAY_LOCALIO;
+	__be32 beres;
+
+	/* Save creds before calling into nfsd */
+	save_cred = get_current_cred();
+
+	rqstp = nfsd_local_fakerqst_create(rpc_clnt, cred);
+	if (IS_ERR(rqstp)) {
+		status = PTR_ERR(rqstp);
+		goto out_revertcred;
+	}
+
+	/* nfs_fh -> svc_fh */
+	if (nfs_fh->size > NFS4_FHSIZE) {
+		status = -EINVAL;
+		goto out;
+	}
+	fh_init(&fh, NFS4_FHSIZE);
+	fh.fh_handle.fh_size = nfs_fh->size;
+	memcpy(fh.fh_handle.fh_raw, nfs_fh->data, nfs_fh->size);
+
+	if (fmode & FMODE_READ)
+		mayflags |= NFSD_MAY_READ;
+	if (fmode & FMODE_WRITE)
+		mayflags |= NFSD_MAY_WRITE;
+
+	beres = nfsd_file_acquire(rqstp, &fh, mayflags, &nf);
+	if (beres) {
+		status = nfs_stat_to_errno(be32_to_cpu(beres));
+		dprintk("%s: fh_verify failed %d\n", __func__, status);
+		goto out_fh_put;
+	}
+
+	*pfilp = get_file(nf->nf_file);
+
+	nfsd_file_put(nf);
+out_fh_put:
+	fh_put(&fh);
+
+out:
+	nfsd_local_fakerqst_destroy(rqstp);
+out_revertcred:
+	revert_creds(save_cred);
+	return status;
+}
+EXPORT_SYMBOL_GPL(nfsd_open_local_fh);
+
+/* Compile time type checking, not used by anything */
+static nfs_to_nfsd_open_t __maybe_unused nfsd_open_local_fh_typecheck = nfsd_open_local_fh;
diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h
index 77bbd23aa150..9c0610fdd11c 100644
--- a/fs/nfsd/trace.h
+++ b/fs/nfsd/trace.h
@@ -86,7 +86,8 @@ DEFINE_NFSD_XDR_ERR_EVENT(cant_encode);
 		{ NFSD_MAY_NOT_BREAK_LEASE,	"NOT_BREAK_LEASE" },	\
 		{ NFSD_MAY_BYPASS_GSS,		"BYPASS_GSS" },		\
 		{ NFSD_MAY_READ_IF_EXEC,	"READ_IF_EXEC" },	\
-		{ NFSD_MAY_64BIT_COOKIE,	"64BIT_COOKIE" })
+		{ NFSD_MAY_64BIT_COOKIE,	"64BIT_COOKIE" },	\
+		{ NFSD_MAY_LOCALIO,		"LOCALIO" })
 
 TRACE_EVENT(nfsd_compound,
 	TP_PROTO(
diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h
index 57cd70062048..91c50649a8c7 100644
--- a/fs/nfsd/vfs.h
+++ b/fs/nfsd/vfs.h
@@ -36,6 +36,8 @@
 #define NFSD_MAY_CREATE		(NFSD_MAY_EXEC|NFSD_MAY_WRITE)
 #define NFSD_MAY_REMOVE		(NFSD_MAY_EXEC|NFSD_MAY_WRITE|NFSD_MAY_TRUNC)
 
+#define NFSD_MAY_LOCALIO		0x800000
+
 struct nfsd_file;
 
 /*
@@ -158,6 +160,12 @@ __be32		nfsd_permission(struct svc_rqst *, struct svc_export *,
 
 void		nfsd_filp_close(struct file *fp);
 
+int		nfsd_open_local_fh(struct rpc_clnt *rpc_clnt,
+				   const struct cred *cred,
+				   const struct nfs_fh *nfs_fh,
+				   const fmode_t fmode,
+				   struct file **pfilp);
+
 static inline int fh_want_write(struct svc_fh *fh)
 {
 	int ret;
diff --git a/include/linux/nfs.h b/include/linux/nfs.h
index b94f51d17bc5..80843764fad3 100644
--- a/include/linux/nfs.h
+++ b/include/linux/nfs.h
@@ -8,6 +8,8 @@
 #ifndef _LINUX_NFS_H
 #define _LINUX_NFS_H
 
+#include <linux/cred.h>
+#include <linux/sunrpc/auth.h>
 #include <linux/sunrpc/msg_prot.h>
 #include <linux/string.h>
 #include <linux/errno.h>
@@ -109,6 +111,10 @@ static inline int nfs_stat_to_errno(enum nfs_stat status)
 	return nfs_common_errtbl[i].errno;
 }
 
+typedef int (*nfs_to_nfsd_open_t)(struct rpc_clnt *, const struct cred *,
+				  const struct nfs_fh *, const fmode_t,
+				  struct file **);
+
 #ifdef CONFIG_CRC32
 /**
  * nfs_fhandle_hash - calculate the crc32 hash for the filehandle
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 039898d70954..a0bb947fdd1d 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -96,6 +96,8 @@ struct nfs_open_context {
 	struct list_head list;
 	struct nfs4_threshold	*mdsthreshold;
 	struct rcu_head	rcu_head;
+
+	struct file *local_filp;
 };
 
 struct nfs_open_dir_context {
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index 82a6f66fe1d0..6b603b0247f1 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -49,12 +49,14 @@ struct nfs_client {
 #define NFS_CS_DS		7		/* - Server is a DS */
 #define NFS_CS_REUSEPORT	8		/* - reuse src port on reconnect */
 #define NFS_CS_PNFS		9		/* - Server used for pnfs */
+#define NFS_CS_LOCAL_IO		10		/* - client is local */
 	struct sockaddr_storage	cl_addr;	/* server identifier */
 	size_t			cl_addrlen;
 	char *			cl_hostname;	/* hostname of server */
 	char *			cl_acceptor;	/* GSSAPI acceptor name */
 	struct list_head	cl_share_link;	/* link in global client list */
 	struct list_head	cl_superblocks;	/* List of nfs_server structs */
+	struct list_head	cl_local_addrs;	/* List of local addresses */
 
 	struct rpc_clnt *	cl_rpcclient;
 	const struct nfs_rpc_ops *rpc_ops;	/* NFS protocol vector */
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index d09b9773b20c..764513a61601 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1605,6 +1605,7 @@ enum {
 	NFS_IOHDR_RESEND_PNFS,
 	NFS_IOHDR_RESEND_MDS,
 	NFS_IOHDR_UNSTABLE_WRITES,
+	NFS_IOHDR_ODIRECT,
 };
 
 struct nfs_io_completion;
