Merge tag 'nfs-for-4.4-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates from Trond Myklebust:
 "Highlights include:

  New features:
   - RDMA client backchannel from Chuck
   - Support for NFSv4.2 file CLONE using the btrfs ioctl

  Bugfixes + cleanups:
   - Move socket data receive out of the bottom halves and into a
     workqueue
   - Refactor NFSv4 error handling so synchronous and asynchronous RPC
     handles errors identically.
   - Fix a panic when blocks or object layouts reads return a bad data
     length
   - Fix nfsroot so it can handle a 1024 byte long path.
   - Fix bad usage of page offset in bl_read_pagelist
   - Various NFSv4 callback cleanups+fixes
   - Fix GETATTR bitmap verification
   - Support hexadecimal number for sunrpc debug sysctl files"

* tag 'nfs-for-4.4-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (53 commits)
  Sunrpc: Supports hexadecimal number for sysctl files of sunrpc debug
  nfs: Fix GETATTR bitmap verification
  nfs: Remove unused xdr page offsets in getacl/setacl arguments
  fs/nfs: remove unnecessary new_valid_dev check
  SUNRPC: fix variable type
  NFS: Enable client side NFSv4.1 backchannel to use other transports
  pNFS/flexfiles: Add support for FF_FLAGS_NO_IO_THRU_MDS
  pNFS/flexfiles: When mirrored, retry failed reads by switching mirrors
  SUNRPC: Remove the TCP-only restriction in bc_svc_process()
  svcrdma: Add backward direction service for RPC/RDMA transport
  xprtrdma: Handle incoming backward direction RPC calls
  xprtrdma: Add support for sending backward direction RPC replies
  xprtrdma: Pre-allocate Work Requests for backchannel
  xprtrdma: Pre-allocate backward rpc_rqst and send/receive buffers
  SUNRPC: Abstract backchannel operations
  xprtrdma: Saving IRQs no longer needed for rb_lock
  xprtrdma: Remove reply tasklet
  xprtrdma: Use workqueue to process RPC/RDMA replies
  xprtrdma: Replace send and receive arrays
  xprtrdma: Refactor reply handler error handling
  ...

23 files changed, 542 insertions, 197 deletions

diff --git a/fs/nfs/blocklayout/blocklayout.c b/fs/nfs/blocklayout/blocklayout.c
index 9cd4eb3..ddd0138 100644
--- a/fs/nfs/blocklayout/blocklayout.c
+++ b/fs/nfs/blocklayout/blocklayout.c
@@ -229,7 +229,7 @@ bl_read_pagelist(struct nfs_pgio_header *header)
 	struct parallel_io *par;
 	loff_t f_offset = header->args.offset;
 	size_t bytes_left = header->args.count;
-	unsigned int pg_offset, pg_len;
+	unsigned int pg_offset = header->args.pgbase, pg_len;
 	struct page **pages = header->args.pages;
 	int pg_index = header->args.pgbase >> PAGE_CACHE_SHIFT;
 	const bool is_dio = (header->dreq != NULL);
@@ -262,7 +262,6 @@ bl_read_pagelist(struct nfs_pgio_header *header)
 			extent_length = be.be_length - (isect - be.be_f_offset);
 		}
 
-		pg_offset = f_offset & ~PAGE_CACHE_MASK;
 		if (is_dio) {
 			if (pg_offset + bytes_left > PAGE_CACHE_SIZE)
 				pg_len = PAGE_CACHE_SIZE - pg_offset;
@@ -273,9 +272,6 @@ bl_read_pagelist(struct nfs_pgio_header *header)
 			pg_len = PAGE_CACHE_SIZE;
 		}
 
-		isect += (pg_offset >> SECTOR_SHIFT);
-		extent_length -= (pg_offset >> SECTOR_SHIFT);
-
 		if (is_hole(&be)) {
 			bio = bl_submit_bio(READ, bio);
 			/* Fill hole w/ zeroes w/o accessing device */
@@ -301,6 +297,7 @@ bl_read_pagelist(struct nfs_pgio_header *header)
 		extent_length -= (pg_len >> SECTOR_SHIFT);
 		f_offset += pg_len;
 		bytes_left -= pg_len;
+		pg_offset = 0;
 	}
 	if ((isect << SECTOR_SHIFT) >= header->inode->i_size) {
 		header->res.eof = 1;
diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index 75f7c0a..a7f2e6e 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -99,17 +99,6 @@ nfs4_callback_up(struct svc_serv *serv)
 }
 
 #if defined(CONFIG_NFS_V4_1)
-static int nfs41_callback_up_net(struct svc_serv *serv, struct net *net)
-{
-	/*
-	 * Create an svc_sock for the back channel service that shares the
-	 * fore channel connection.
-	 * Returns the input port (0) and sets the svc_serv bc_xprt on success
-	 */
-	return svc_create_xprt(serv, "tcp-bc", net, PF_INET, 0,
-			      SVC_SOCK_ANONYMOUS);
-}
-
 /*
  * The callback service for NFSv4.1 callbacks
  */
@@ -184,11 +173,6 @@ static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
 		xprt->bc_serv = serv;
 }
 #else
-static int nfs41_callback_up_net(struct svc_serv *serv, struct net *net)
-{
-	return 0;
-}
-
 static void nfs_minorversion_callback_svc_setup(struct svc_serv *serv,
 		struct svc_rqst **rqstpp, int (**callback_svc)(void *vrqstp))
 {
@@ -259,7 +243,8 @@ static void nfs_callback_down_net(u32 minorversion, struct svc_serv *serv, struc
 	svc_shutdown_net(serv, net);
 }
 
-static int nfs_callback_up_net(int minorversion, struct svc_serv *serv, struct net *net)
+static int nfs_callback_up_net(int minorversion, struct svc_serv *serv,
+			       struct net *net, struct rpc_xprt *xprt)
 {
 	struct nfs_net *nn = net_generic(net, nfs_net_id);
 	int ret;
@@ -275,20 +260,11 @@ static int nfs_callback_up_net(int minorversion, struct svc_serv *serv, struct n
 		goto err_bind;
 	}
 
-	switch (minorversion) {
-		case 0:
-			ret = nfs4_callback_up_net(serv, net);
-			break;
-		case 1:
-		case 2:
-			ret = nfs41_callback_up_net(serv, net);
-			break;
-		default:
-			printk(KERN_ERR "NFS: unknown callback version: %d\n",
-					minorversion);
-			ret = -EINVAL;
-			break;
-	}
+	ret = -EPROTONOSUPPORT;
+	if (minorversion == 0)
+		ret = nfs4_callback_up_net(serv, net);
+	else if (xprt->ops->bc_up)
+		ret = xprt->ops->bc_up(serv, net);
 
 	if (ret < 0) {
 		printk(KERN_ERR "NFS: callback service start failed\n");
@@ -364,7 +340,7 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 		goto err_create;
 	}
 
-	ret = nfs_callback_up_net(minorversion, serv, net);
+	ret = nfs_callback_up_net(minorversion, serv, net, xprt);
 	if (ret < 0)
 		goto err_net;
 
diff --git a/fs/nfs/callback.h b/fs/nfs/callback.h
index 84326e9..ff8195b 100644
--- a/fs/nfs/callback.h
+++ b/fs/nfs/callback.h
@@ -61,7 +61,6 @@ struct cb_compound_hdr_res {
 };
 
 struct cb_getattrargs {
-	struct sockaddr *addr;
 	struct nfs_fh fh;
 	uint32_t bitmap[2];
 };
@@ -76,7 +75,6 @@ struct cb_getattrres {
 };
 
 struct cb_recallargs {
-	struct sockaddr *addr;
 	struct nfs_fh fh;
 	nfs4_stateid stateid;
 	uint32_t truncate;
@@ -119,9 +117,6 @@ extern __be32 nfs4_callback_sequence(struct cb_sequenceargs *args,
 				       struct cb_sequenceres *res,
 				       struct cb_process_state *cps);
 
-extern int nfs41_validate_delegation_stateid(struct nfs_delegation *delegation,
-					     const nfs4_stateid *stateid);
-
 #define RCA4_TYPE_MASK_RDATA_DLG	0
 #define RCA4_TYPE_MASK_WDATA_DLG	1
 #define RCA4_TYPE_MASK_DIR_DLG         2
@@ -134,7 +129,6 @@ extern int nfs41_validate_delegation_stateid(struct nfs_delegation *delegation,
 #define RCA4_TYPE_MASK_ALL 0xf31f
 
 struct cb_recallanyargs {
-	struct sockaddr	*craa_addr;
 	uint32_t	craa_objs_to_keep;
 	uint32_t	craa_type_mask;
 };
@@ -144,7 +138,6 @@ extern __be32 nfs4_callback_recallany(struct cb_recallanyargs *args,
 					struct cb_process_state *cps);
 
 struct cb_recallslotargs {
-	struct sockaddr	*crsa_addr;
 	uint32_t	crsa_target_highest_slotid;
 };
 extern __be32 nfs4_callback_recallslot(struct cb_recallslotargs *args,
@@ -152,7 +145,6 @@ extern __be32 nfs4_callback_recallslot(struct cb_recallslotargs *args,
 					 struct cb_process_state *cps);
 
 struct cb_layoutrecallargs {
-	struct sockaddr		*cbl_addr;
 	uint32_t		cbl_recall_type;
 	uint32_t		cbl_layout_type;
 	uint32_t		cbl_layoutchanged;
@@ -196,9 +188,6 @@ extern __be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy,
 #if IS_ENABLED(CONFIG_NFS_V4)
 extern int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt);
 extern void nfs_callback_down(int minorversion, struct net *net);
-extern int nfs4_validate_delegation_stateid(struct nfs_delegation *delegation,
-					    const nfs4_stateid *stateid);
-extern int nfs4_set_callback_sessionid(struct nfs_client *clp);
 #endif /* CONFIG_NFS_V4 */
 /*
  * nfs41: Callbacks are expected to not cause substantial latency,
@@ -209,6 +198,5 @@ extern int nfs4_set_callback_sessionid(struct nfs_client *clp);
 #define NFS41_BC_MAX_CALLBACKS 1
 
 extern unsigned int nfs_callback_set_tcpport;
-extern unsigned short nfs_callback_tcpport;
 
 #endif /* __LINUX_FS_NFS_CALLBACK_H */
diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index b85cf7a..807eb6e 100644
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -17,9 +17,7 @@
 #include "nfs4session.h"
 #include "nfs4trace.h"
 
-#ifdef NFS_DEBUG
 #define NFSDBG_FACILITY NFSDBG_CALLBACK
-#endif
 
 __be32 nfs4_callback_getattr(struct cb_getattrargs *args,
 			     struct cb_getattrres *res,
diff --git a/fs/nfs/callback_xdr.c b/fs/nfs/callback_xdr.c
index 6b1697a..646cdac 100644
--- a/fs/nfs/callback_xdr.c
+++ b/fs/nfs/callback_xdr.c
@@ -18,19 +18,21 @@
 #include "internal.h"
 #include "nfs4session.h"
 
-#define CB_OP_TAGLEN_MAXSZ	(512)
-#define CB_OP_HDR_RES_MAXSZ	(2 + CB_OP_TAGLEN_MAXSZ)
-#define CB_OP_GETATTR_BITMAP_MAXSZ	(4)
-#define CB_OP_GETATTR_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ + \
-				CB_OP_GETATTR_BITMAP_MAXSZ + \
-				2 + 2 + 3 + 3)
-#define CB_OP_RECALL_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
+#define CB_OP_TAGLEN_MAXSZ		(512)
+#define CB_OP_HDR_RES_MAXSZ		(2 * 4) // opcode, status
+#define CB_OP_GETATTR_BITMAP_MAXSZ	(4 * 4) // bitmap length, 3 bitmaps
+#define CB_OP_GETATTR_RES_MAXSZ		(CB_OP_HDR_RES_MAXSZ + \
+					 CB_OP_GETATTR_BITMAP_MAXSZ + \
+					 /* change, size, ctime, mtime */\
+					 (2 + 2 + 3 + 3) * 4)
+#define CB_OP_RECALL_RES_MAXSZ		(CB_OP_HDR_RES_MAXSZ)
 
 #if defined(CONFIG_NFS_V4_1)
 #define CB_OP_LAYOUTRECALL_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
 #define CB_OP_DEVICENOTIFY_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
 #define CB_OP_SEQUENCE_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ + \
-					4 + 1 + 3)
+					 NFS4_MAX_SESSIONID_LEN + \
+					 (1 + 3) * 4) // seqid, 3 slotids
 #define CB_OP_RECALLANY_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
 #define CB_OP_RECALLSLOT_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
 #endif /* CONFIG_NFS_V4_1 */
@@ -157,7 +159,7 @@ static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound
 	if (unlikely(status != 0))
 		return status;
 	/* We do not like overly long tags! */
-	if (hdr->taglen > CB_OP_TAGLEN_MAXSZ - 12) {
+	if (hdr->taglen > CB_OP_TAGLEN_MAXSZ) {
 		printk("NFS: NFSv4 CALLBACK %s: client sent tag of length %u\n",
 				__func__, hdr->taglen);
 		return htonl(NFS4ERR_RESOURCE);
@@ -198,7 +200,6 @@ static __be32 decode_getattr_args(struct svc_rqst *rqstp, struct xdr_stream *xdr
 	status = decode_fh(xdr, &args->fh);
 	if (unlikely(status != 0))
 		goto out;
-	args->addr = svc_addr(rqstp);
 	status = decode_bitmap(xdr, args->bitmap);
 out:
 	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
@@ -210,7 +211,6 @@ static __be32 decode_recall_args(struct svc_rqst *rqstp, struct xdr_stream *xdr,
 	__be32 *p;
 	__be32 status;
 
-	args->addr = svc_addr(rqstp);
 	status = decode_stateid(xdr, &args->stateid);
 	if (unlikely(status != 0))
 		goto out;
@@ -236,7 +236,6 @@ static __be32 decode_layoutrecall_args(struct svc_rqst *rqstp,
 	__be32 status = 0;
 	uint32_t iomode;
 
-	args->cbl_addr = svc_addr(rqstp);
 	p = read_buf(xdr, 4 * sizeof(uint32_t));
 	if (unlikely(p == NULL)) {
 		status = htonl(NFS4ERR_BADXDR);
@@ -383,13 +382,12 @@ static __be32 decode_sessionid(struct xdr_stream *xdr,
 				 struct nfs4_sessionid *sid)
 {
 	__be32 *p;
-	int len = NFS4_MAX_SESSIONID_LEN;
 
-	p = read_buf(xdr, len);
+	p = read_buf(xdr, NFS4_MAX_SESSIONID_LEN);
 	if (unlikely(p == NULL))
 		return htonl(NFS4ERR_RESOURCE);
 
-	memcpy(sid->data, p, len);
+	memcpy(sid->data, p, NFS4_MAX_SESSIONID_LEN);
 	return 0;
 }
 
@@ -500,7 +498,6 @@ static __be32 decode_recallany_args(struct svc_rqst *rqstp,
 	uint32_t bitmap[2];
 	__be32 *p, status;
 
-	args->craa_addr = svc_addr(rqstp);
 	p = read_buf(xdr, 4);
 	if (unlikely(p == NULL))
 		return htonl(NFS4ERR_BADXDR);
@@ -519,7 +516,6 @@ static __be32 decode_recallslot_args(struct svc_rqst *rqstp,
 {
 	__be32 *p;
 
-	args->crsa_addr = svc_addr(rqstp);
 	p = read_buf(xdr, 4);
 	if (unlikely(p == NULL))
 		return htonl(NFS4ERR_BADXDR);
@@ -684,13 +680,12 @@ static __be32 encode_sessionid(struct xdr_stream *xdr,
 				 const struct nfs4_sessionid *sid)
 {
 	__be32 *p;
-	int len = NFS4_MAX_SESSIONID_LEN;
 
-	p = xdr_reserve_space(xdr, len);
+	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN);
 	if (unlikely(p == NULL))
 		return htonl(NFS4ERR_RESOURCE);
 
-	memcpy(p, sid, len);
+	memcpy(p, sid, NFS4_MAX_SESSIONID_LEN);
 	return 0;
 }
 
@@ -704,7 +699,9 @@ static __be32 encode_cb_sequence_res(struct svc_rqst *rqstp,
 	if (unlikely(status != 0))
 		goto out;
 
-	encode_sessionid(xdr, &res->csr_sessionid);
+	status = encode_sessionid(xdr, &res->csr_sessionid);
+	if (status)
+		goto out;
 
 	p = xdr_reserve_space(xdr, 4 * sizeof(uint32_t));
 	if (unlikely(p == NULL))
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 57c5a02..d6d5d2a 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -764,6 +764,7 @@ static void nfs_server_set_fsinfo(struct nfs_server *server,
 
 	server->time_delta = fsinfo->time_delta;
 
+	server->clone_blksize = fsinfo->clone_blksize;
 	/* We're airborne Set socket buffersize */
 	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
 }
diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index be806ea..5166adc 100644
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -721,14 +721,12 @@ int nfs_async_inode_return_delegation(struct inode *inode,
 	struct nfs_client *clp = server->nfs_client;
 	struct nfs_delegation *delegation;
 
-	filemap_flush(inode->i_mapping);
-
 	rcu_read_lock();
 	delegation = rcu_dereference(NFS_I(inode)->delegation);
 	if (delegation == NULL)
 		goto out_enoent;
-
-	if (!clp->cl_mvops->match_stateid(&delegation->stateid, stateid))
+	if (stateid != NULL &&
+	    !clp->cl_mvops->match_stateid(&delegation->stateid, stateid))
 		goto out_enoent;
 	nfs_mark_return_delegation(server, delegation);
 	rcu_read_unlock();
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 3d8e4ff..ce5a218 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1714,9 +1714,6 @@ nfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t rdev)
 	dfprintk(VFS, "NFS: mknod(%s/%lu), %pd\n",
 			dir->i_sb->s_id, dir->i_ino, dentry);
 
-	if (!new_valid_dev(rdev))
-		return -EINVAL;
-
 	attr.ia_mode = mode;
 	attr.ia_valid = ATTR_MODE;
 
diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index fbc5a56..03516c8 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -339,6 +339,19 @@ static void ff_layout_sort_mirrors(struct nfs4_ff_layout_segment *fls)
 	}
 }
 
+static void ff_layout_mark_devices_valid(struct nfs4_ff_layout_segment *fls)
+{
+	struct nfs4_deviceid_node *node;
+	int i;
+
+	if (!(fls->flags & FF_FLAGS_NO_IO_THRU_MDS))
+		return;
+	for (i = 0; i < fls->mirror_array_cnt; i++) {
+		node = &fls->mirror_array[i]->mirror_ds->id_node;
+		clear_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags);
+	}
+}
+
 static struct pnfs_layout_segment *
 ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 		     struct nfs4_layoutget_res *lgr,
@@ -499,6 +512,7 @@ ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 	rc = ff_layout_check_layout(lgr);
 	if (rc)
 		goto out_err_free;
+	ff_layout_mark_devices_valid(fls);
 
 	ret = &fls->generic_hdr;
 	dprintk("<-- %s (success)\n", __func__);
@@ -741,17 +755,17 @@ ff_layout_alloc_commit_info(struct pnfs_layout_segment *lseg,
 }
 
 static struct nfs4_pnfs_ds *
-ff_layout_choose_best_ds_for_read(struct nfs_pageio_descriptor *pgio,
+ff_layout_choose_best_ds_for_read(struct pnfs_layout_segment *lseg,
+				  int start_idx,
 				  int *best_idx)
 {
-	struct nfs4_ff_layout_segment *fls;
+	struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 	struct nfs4_pnfs_ds *ds;
 	int idx;
 
-	fls = FF_LAYOUT_LSEG(pgio->pg_lseg);
 	/* mirrors are sorted by efficiency */
-	for (idx = 0; idx < fls->mirror_array_cnt; idx++) {
-		ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, idx, false);
+	for (idx = start_idx; idx < fls->mirror_array_cnt; idx++) {
+		ds = nfs4_ff_layout_prepare_ds(lseg, idx, false);
 		if (ds) {
 			*best_idx = idx;
 			return ds;
@@ -782,7 +796,7 @@ ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 	if (pgio->pg_lseg == NULL)
 		goto out_mds;
 
-	ds = ff_layout_choose_best_ds_for_read(pgio, &ds_idx);
+	ds = ff_layout_choose_best_ds_for_read(pgio->pg_lseg, 0, &ds_idx);
 	if (!ds)
 		goto out_mds;
 	mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
@@ -1035,7 +1049,8 @@ static int ff_layout_async_handle_error_v4(struct rpc_task *task,
 		rpc_wake_up(&tbl->slot_tbl_waitq);
 		/* fall through */
 	default:
-		if (ff_layout_has_available_ds(lseg))
+		if (ff_layout_no_fallback_to_mds(lseg) ||
+		    ff_layout_has_available_ds(lseg))
 			return -NFS4ERR_RESET_TO_PNFS;
 reset:
 		dprintk("%s Retry through MDS. Error %d\n", __func__,
@@ -1153,7 +1168,6 @@ static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
 }
 
 /* NFS_PROTO call done callback routines */
-
 static int ff_layout_read_done_cb(struct rpc_task *task,
 				struct nfs_pgio_header *hdr)
 {
@@ -1171,6 +1185,10 @@ static int ff_layout_read_done_cb(struct rpc_task *task,
 
 	switch (err) {
 	case -NFS4ERR_RESET_TO_PNFS:
+		if (ff_layout_choose_best_ds_for_read(hdr->lseg,
+					hdr->pgio_mirror_idx + 1,
+					&hdr->pgio_mirror_idx))
+			goto out_eagain;
 		set_bit(NFS_LAYOUT_RETURN_BEFORE_CLOSE,
 			&hdr->lseg->pls_layout->plh_flags);
 		pnfs_read_resend_pnfs(hdr);
@@ -1179,11 +1197,13 @@ static int ff_layout_read_done_cb(struct rpc_task *task,
 		ff_layout_reset_read(hdr);
 		return task->tk_status;
 	case -EAGAIN:
-		rpc_restart_call_prepare(task);
-		return -EAGAIN;
+		goto out_eagain;
 	}
 
 	return 0;
+out_eagain:
+	rpc_restart_call_prepare(task);
+	return -EAGAIN;
 }
 
 static bool
diff --git a/fs/nfs/flexfilelayout/flexfilelayout.h b/fs/nfs/flexfilelayout/flexfilelayout.h
index 68cc0d9..2bb08bc 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.h
+++ b/fs/nfs/flexfilelayout/flexfilelayout.h
@@ -10,6 +10,7 @@
 #define FS_NFS_NFS4FLEXFILELAYOUT_H
 
 #define FF_FLAGS_NO_LAYOUTCOMMIT 1
+#define FF_FLAGS_NO_IO_THRU_MDS 2
 
 #include "../pnfs.h"
 
@@ -146,6 +147,12 @@ FF_LAYOUT_MIRROR_COUNT(struct pnfs_layout_segment *lseg)
 }
 
 static inline bool
+ff_layout_no_fallback_to_mds(struct pnfs_layout_segment *lseg)
+{
+	return FF_LAYOUT_LSEG(lseg)->flags & FF_FLAGS_NO_IO_THRU_MDS;
+}
+
+static inline bool
 ff_layout_test_devid_unavailable(struct nfs4_deviceid_node *node)
 {
 	return nfs4_test_deviceid_unavailable(node);
diff --git a/fs/nfs/mount_clnt.c b/fs/nfs/mount_clnt.c
index 99a4528..09b1900 100644
--- a/fs/nfs/mount_clnt.c
+++ b/fs/nfs/mount_clnt.c
@@ -16,9 +16,7 @@
 #include <linux/nfs_fs.h>
 #include "internal.h"
 
-#ifdef NFS_DEBUG
-# define NFSDBG_FACILITY	NFSDBG_MOUNT
-#endif
+#define NFSDBG_FACILITY	NFSDBG_MOUNT
 
 /*
  * Defined by RFC 1094, section A.3; and RFC 1813, section 5.1.4
diff --git a/fs/nfs/nfs42.h b/fs/nfs/nfs42.h
index 814c125..b587ccd 100644
--- a/fs/nfs/nfs42.h
+++ b/fs/nfs/nfs42.h
@@ -17,5 +17,6 @@ int nfs42_proc_deallocate(struct file *, loff_t, loff_t);
 loff_t nfs42_proc_llseek(struct file *, loff_t, int);
 int nfs42_proc_layoutstats_generic(struct nfs_server *,
 				   struct nfs42_layoutstat_data *);
+int nfs42_proc_clone(struct file *, struct file *, loff_t, loff_t, loff_t);
 
 #endif /* __LINUX_FS_NFS_NFS4_2_H */
diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c
index 0f020e4..3e92a3c 100644
--- a/fs/nfs/nfs42proc.c
+++ b/fs/nfs/nfs42proc.c
@@ -271,3 +271,74 @@ int nfs42_proc_layoutstats_generic(struct nfs_server *server,
 		return PTR_ERR(task);
 	return 0;
 }
+
+static int _nfs42_proc_clone(struct rpc_message *msg, struct file *src_f,
+			     struct file *dst_f, loff_t src_offset,
+			     loff_t dst_offset, loff_t count)
+{
+	struct inode *src_inode = file_inode(src_f);
+	struct inode *dst_inode = file_inode(dst_f);
+	struct nfs_server *server = NFS_SERVER(dst_inode);
+	struct nfs42_clone_args args = {
+		.src_fh = NFS_FH(src_inode),
+		.dst_fh = NFS_FH(dst_inode),
+		.src_offset = src_offset,
+		.dst_offset = dst_offset,
+		.dst_bitmask = server->cache_consistency_bitmask,
+	};
+	struct nfs42_clone_res res = {
+		.server	= server,
+	};
+	int status;
+
+	msg->rpc_argp = &args;
+	msg->rpc_resp = &res;
+
+	status = nfs42_set_rw_stateid(&args.src_stateid, src_f, FMODE_READ);
+	if (status)
+		return status;
+
+	status = nfs42_set_rw_stateid(&args.dst_stateid, dst_f, FMODE_WRITE);
+	if (status)
+		return status;
+
+	res.dst_fattr = nfs_alloc_fattr();
+	if (!res.dst_fattr)
+		return -ENOMEM;
+
+	status = nfs4_call_sync(server->client, server, msg,
+				&args.seq_args, &res.seq_res, 0);
+	if (status == 0)
+		status = nfs_post_op_update_inode(dst_inode, res.dst_fattr);
+
+	kfree(res.dst_fattr);
+	return status;
+}
+
+int nfs42_proc_clone(struct file *src_f, struct file *dst_f,
+		     loff_t src_offset, loff_t dst_offset, loff_t count)
+{
+	struct rpc_message msg = {
+		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_CLONE],
+	};
+	struct inode *inode = file_inode(src_f);
+	struct nfs_server *server = NFS_SERVER(file_inode(src_f));
+	struct nfs4_exception exception = { };
+	int err;
+
+	if (!nfs_server_capable(inode, NFS_CAP_CLONE))
+		return -EOPNOTSUPP;
+
+	do {
+		err = _nfs42_proc_clone(&msg, src_f, dst_f, src_offset,
+					dst_offset, count);
+		if (err == -ENOTSUPP || err == -EOPNOTSUPP) {
+			NFS_SERVER(inode)->caps &= ~NFS_CAP_CLONE;
+			return -EOPNOTSUPP;
+		}
+		err = nfs4_handle_exception(server, err, &exception);
+	} while (exception.retry);
+
+	return err;
+
+}
diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c
index 0eb29e1..0ca482a 100644
--- a/fs/nfs/nfs42xdr.c
+++ b/fs/nfs/nfs42xdr.c
@@ -34,6 +34,12 @@
 					1 /* opaque devaddr4 length */ + \
 					XDR_QUADLEN(PNFS_LAYOUTSTATS_MAXSIZE))
 #define decode_layoutstats_maxsz	(op_decode_hdr_maxsz)
+#define encode_clone_maxsz		(encode_stateid_maxsz + \
+					encode_stateid_maxsz + \
+					2 /* src offset */ + \
+					2 /* dst offset */ + \
+					2 /* count */)
+#define decode_clone_maxsz		(op_decode_hdr_maxsz)
 
 #define NFS4_enc_allocate_sz		(compound_encode_hdr_maxsz + \
 					 encode_putfh_maxsz + \
@@ -65,7 +71,20 @@
 					 decode_sequence_maxsz + \
 					 decode_putfh_maxsz + \
 					 PNFS_LAYOUTSTATS_MAXDEV * decode_layoutstats_maxsz)
-
+#define NFS4_enc_clone_sz		(compound_encode_hdr_maxsz + \
+					 encode_sequence_maxsz + \
+					 encode_putfh_maxsz + \
+					 encode_savefh_maxsz + \
+					 encode_putfh_maxsz + \
+					 encode_clone_maxsz + \
+					 encode_getattr_maxsz)
+#define NFS4_dec_clone_sz		(compound_decode_hdr_maxsz + \
+					 decode_sequence_maxsz + \
+					 decode_putfh_maxsz + \
+					 decode_savefh_maxsz + \
+					 decode_putfh_maxsz + \
+					 decode_clone_maxsz + \
+					 decode_getattr_maxsz)
 
 static void encode_fallocate(struct xdr_stream *xdr,
 			     struct nfs42_falloc_args *args)
@@ -128,6 +147,21 @@ static void encode_layoutstats(struct xdr_stream *xdr,
 		encode_uint32(xdr, 0);
 }
 
+static void encode_clone(struct xdr_stream *xdr,
+			 struct nfs42_clone_args *args,
+			 struct compound_hdr *hdr)
+{
+	__be32 *p;
+
+	encode_op_hdr(xdr, OP_CLONE, decode_clone_maxsz, hdr);
+	encode_nfs4_stateid(xdr, &args->src_stateid);
+	encode_nfs4_stateid(xdr, &args->dst_stateid);
+	p = reserve_space(xdr, 3*8);
+	p = xdr_encode_hyper(p, args->src_offset);
+	p = xdr_encode_hyper(p, args->dst_offset);
+	xdr_encode_hyper(p, args->count);
+}
+
 /*
  * Encode ALLOCATE request
  */
@@ -206,6 +240,27 @@ static void nfs4_xdr_enc_layoutstats(struct rpc_rqst *req,
 	encode_nops(&hdr);
 }
 
+/*
+ * Encode CLONE request
+ */
+static void nfs4_xdr_enc_clone(struct rpc_rqst *req,
+			       struct xdr_stream *xdr,
+			       struct nfs42_clone_args *args)
+{
+	struct compound_hdr hdr = {
+		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
+	};
+
+	encode_compound_hdr(xdr, req, &hdr);
+	encode_sequence(xdr, &args->seq_args, &hdr);
+	encode_putfh(xdr, args->src_fh, &hdr);
+	encode_savefh(xdr, &hdr);
+	encode_putfh(xdr, args->dst_fh, &hdr);
+	encode_clone(xdr, args, &hdr);
+	encode_getfattr(xdr, args->dst_bitmask, &hdr);
+	encode_nops(&hdr);
+}
+
 static int decode_allocate(struct xdr_stream *xdr, struct nfs42_falloc_res *res)
 {
 	return decode_op_hdr(xdr, OP_ALLOCATE);
@@ -243,6 +298,11 @@ static int decode_layoutstats(struct xdr_stream *xdr)
 	return decode_op_hdr(xdr, OP_LAYOUTSTATS);
 }
 
+static int decode_clone(struct xdr_stream *xdr)
+{
+	return decode_op_hdr(xdr, OP_CLONE);
+}
+
 /*
  * Decode ALLOCATE request
  */
@@ -351,4 +411,39 @@ out:
 	return status;
 }
 
+/*
+ * Decode CLONE request
+ */
+static int nfs4_xdr_dec_clone(struct rpc_rqst *rqstp,
+			      struct xdr_stream *xdr,
+			      struct nfs42_clone_res *res)
+{
+	struct compound_hdr hdr;
+	int status;
+
+	status = decode_compound_hdr(xdr, &hdr);
+	if (status)
+		goto out;
+	status = decode_sequence(xdr, &res->seq_res, rqstp);
+	if (status)
+		goto out;
+	status = decode_putfh(xdr);
+	if (status)
+		goto out;
+	status = decode_savefh(xdr);
+	if (status)
+		goto out;
+	status = decode_putfh(xdr);
+	if (status)
+		goto out;
+	status = decode_clone(xdr);
+	if (status)
+		goto out;
+	status = decode_getfattr(xdr, res->dst_fattr, res->server);
+
+out:
+	res->rpc_status = status;
+	return status;
+}
+
 #endif /* __LINUX_FS_NFS_NFS4_2XDR_H */
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index 50cfc4c..4afdee4 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -183,10 +183,12 @@ struct nfs4_state {
 
 
 struct nfs4_exception {
-	long timeout;
-	int retry;
 	struct nfs4_state *state;
 	struct inode *inode;
+	long timeout;
+	unsigned char delay : 1,
+		      recovering : 1,
+		      retry : 1;
 };
 
 struct nfs4_state_recovery_ops {
diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
index b0dbe0a..4aa5719 100644
--- a/fs/nfs/nfs4file.c
+++ b/fs/nfs/nfs4file.c
@@ -4,6 +4,7 @@
  *  Copyright (C) 1992  Rick Sladkey
  */
 #include <linux/fs.h>
+#include <linux/file.h>
 #include <linux/falloc.h>
 #include <linux/nfs_fs.h>
 #include "delegation.h"
@@ -192,8 +193,138 @@ static long nfs42_fallocate(struct file *filep, int mode, loff_t offset, loff_t
 		return nfs42_proc_deallocate(filep, offset, len);
 	return nfs42_proc_allocate(filep, offset, len);
 }
+
+static noinline long
+nfs42_ioctl_clone(struct file *dst_file, unsigned long srcfd,
+		  u64 src_off, u64 dst_off, u64 count)
+{
+	struct inode *dst_inode = file_inode(dst_file);
+	struct nfs_server *server = NFS_SERVER(dst_inode);
+	struct fd src_file;
+	struct inode *src_inode;
+	unsigned int bs = server->clone_blksize;
+	int ret;
+
+	/* dst file must be opened for writing */
+	if (!(dst_file->f_mode & FMODE_WRITE))
+		return -EINVAL;
+
+	ret = mnt_want_write_file(dst_file);
+	if (ret)
+		return ret;
+
+	src_file = fdget(srcfd);
+	if (!src_file.file) {
+		ret = -EBADF;
+		goto out_drop_write;
+	}
+
+	src_inode = file_inode(src_file.file);
+
+	/* src and dst must be different files */
+	ret = -EINVAL;
+	if (src_inode == dst_inode)
+		goto out_fput;
+
+	/* src file must be opened for reading */
+	if (!(src_file.file->f_mode & FMODE_READ))
+		goto out_fput;
+
+	/* src and dst must be regular files */
+	ret = -EISDIR;
+	if (!S_ISREG(src_inode->i_mode) || !S_ISREG(dst_inode->i_mode))
+		goto out_fput;
+
+	ret = -EXDEV;
+	if (src_file.file->f_path.mnt != dst_file->f_path.mnt ||
+	    src_inode->i_sb != dst_inode->i_sb)
+		goto out_fput;
+
+	/* check alignment w.r.t. clone_blksize */
+	ret = -EINVAL;
+	if (bs) {
+		if (!IS_ALIGNED(src_off, bs) || !IS_ALIGNED(dst_off, bs))
+			goto out_fput;
+		if (!IS_ALIGNED(count, bs) && i_size_read(src_inode) != (src_off + count))
+			goto out_fput;
+	}
+
+	/* XXX: do we lock at all? what if server needs CB_RECALL_LAYOUT? */
+	if (dst_inode < src_inode) {
+		mutex_lock_nested(&dst_inode->i_mutex, I_MUTEX_PARENT);
+		mutex_lock_nested(&src_inode->i_mutex, I_MUTEX_CHILD);
+	} else {
+		mutex_lock_nested(&src_inode->i_mutex, I_MUTEX_PARENT);
+		mutex_lock_nested(&dst_inode->i_mutex, I_MUTEX_CHILD);
+	}
+
+	/* flush all pending writes on both src and dst so that server
+	 * has the latest data */
+	ret = nfs_sync_inode(src_inode);
+	if (ret)
+		goto out_unlock;
+	ret = nfs_sync_inode(dst_inode);
+	if (ret)
+		goto out_unlock;
+
+	ret = nfs42_proc_clone(src_file.file, dst_file, src_off, dst_off, count);
+
+	/* truncate inode page cache of the dst range so that future reads can fetch
+	 * new data from server */
+	if (!ret)
+		truncate_inode_pages_range(&dst_inode->i_data, dst_off, dst_off + count - 1);
+
+out_unlock:
+	if (dst_inode < src_inode) {
+		mutex_unlock(&src_inode->i_mutex);
+		mutex_unlock(&dst_inode->i_mutex);
+	} else {
+		mutex_unlock(&dst_inode->i_mutex);
+		mutex_unlock(&src_inode->i_mutex);
+	}
+out_fput:
+	fdput(src_file);
+out_drop_write:
+	mnt_drop_write_file(dst_file);
+	return ret;
+}
+
+static long nfs42_ioctl_clone_range(struct file *dst_file, void __user *argp)
+{
+	struct nfs_ioctl_clone_range_args args;
+
+	if (copy_from_user(&args, argp, sizeof(args)))
+		return -EFAULT;
+
+	return nfs42_ioctl_clone(dst_file, args.src_fd, args.src_off, args.dst_off, args.count);
+}
+#else
+static long nfs42_ioctl_clone(struct file *dst_file, unsigned long srcfd,
+		u64 src_off, u64 dst_off, u64 count)
+{
+	return -ENOTTY;
+}
+
+static long nfs42_ioctl_clone_range(struct file *dst_file, void __user *argp)
+{
+	return -ENOTTY;
+}
 #endif /* CONFIG_NFS_V4_2 */
 
+long nfs4_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+	void __user *argp = (void __user *)arg;
+
+	switch (cmd) {
+	case NFS_IOC_CLONE:
+		return nfs42_ioctl_clone(file, arg, 0, 0, 0);
+	case NFS_IOC_CLONE_RANGE:
+		return nfs42_ioctl_clone_range(file, argp);
+	}
+
+	return -ENOTTY;
+}
+
 const struct file_operations nfs4_file_operations = {
 #ifdef CONFIG_NFS_V4_2
 	.llseek		= nfs4_file_llseek,
@@ -216,4 +347,9 @@ const struct file_operations nfs4_file_operations = {
 #endif /* CONFIG_NFS_V4_2 */
 	.check_flags	= nfs_check_flags,
 	.setlease	= simple_nosetlease,
+#ifdef CONFIG_COMPAT
+	.unlocked_ioctl = nfs4_ioctl,
+#else
+	.compat_ioctl	= nfs4_ioctl,
+#endif /* CONFIG_COMPAT */
 };
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 0e5ff69..ff5bddc 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -78,7 +78,6 @@ struct nfs4_opendata;
 static int _nfs4_proc_open(struct nfs4_opendata *data);
 static int _nfs4_recover_proc_open(struct nfs4_opendata *data);
 static int nfs4_do_fsinfo(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *);
-static int nfs4_async_handle_error(struct rpc_task *, const struct nfs_server *, struct nfs4_state *, long *);
 static void nfs_fixup_referral_attributes(struct nfs_fattr *fattr);
 static int nfs4_proc_getattr(struct nfs_server *, struct nfs_fh *, struct nfs_fattr *, struct nfs4_label *label);
 static int _nfs4_proc_getattr(struct nfs_server *server, struct nfs_fh *fhandle, struct nfs_fattr *fattr, struct nfs4_label *label);
@@ -239,6 +238,7 @@ const u32 nfs4_fsinfo_bitmap[3] = { FATTR4_WORD0_MAXFILESIZE
 			FATTR4_WORD1_TIME_DELTA
 			| FATTR4_WORD1_FS_LAYOUT_TYPES,
 			FATTR4_WORD2_LAYOUT_BLKSIZE
+			| FATTR4_WORD2_CLONE_BLKSIZE
 };
 
 const u32 nfs4_fs_locations_bitmap[3] = {
@@ -344,13 +344,16 @@ static int nfs4_delay(struct rpc_clnt *clnt, long *timeout)
 /* This is the error handling routine for processes that are allowed
  * to sleep.
  */
-int nfs4_handle_exception(struct nfs_server *server, int errorcode, struct nfs4_exception *exception)
+static int nfs4_do_handle_exception(struct nfs_server *server,
+		int errorcode, struct nfs4_exception *exception)
 {
 	struct nfs_client *clp = server->nfs_client;
 	struct nfs4_state *state = exception->state;
 	struct inode *inode = exception->inode;
 	int ret = errorcode;
 
+	exception->delay = 0;
+	exception->recovering = 0;
 	exception->retry = 0;
 	switch(errorcode) {
 		case 0:
@@ -359,11 +362,9 @@ int nfs4_handle_exception(struct nfs_server *server, int errorcode, struct nfs4_
 		case -NFS4ERR_DELEG_REVOKED:
 		case -NFS4ERR_ADMIN_REVOKED:
 		case -NFS4ERR_BAD_STATEID:
-			if (inode && nfs4_have_delegation(inode, FMODE_READ)) {
-				nfs4_inode_return_delegation(inode);
-				exception->retry = 1;
-				return 0;
-			}
+			if (inode && nfs_async_inode_return_delegation(inode,
+						NULL) == 0)
+				goto wait_on_recovery;
 			if (state == NULL)
 				break;
 			ret = nfs4_schedule_stateid_recovery(server, state);
@@ -409,11 +410,12 @@ int nfs4_handle_exception(struct nfs_server *server, int errorcode, struct nfs4_
 				ret = -EBUSY;
 				break;
 			}
-		case -NFS4ERR_GRACE:
 		case -NFS4ERR_DELAY:
-			ret = nfs4_delay(server->client, &exception->timeout);
-			if (ret != 0)
-				break;
+			nfs_inc_server_stats(server, NFSIOS_DELAY);
+		case -NFS4ERR_GRACE:
+			exception->delay = 1;
+			return 0;
+
 		case -NFS4ERR_RETRY_UNCACHED_REP:
 		case -NFS4ERR_OLD_STATEID:
 			exception->retry = 1;
@@ -434,14 +436,85 @@ int nfs4_handle_exception(struct nfs_server *server, int errorcode, struct nfs4_
 	/* We failed to handle the error */
 	return nfs4_map_errors(ret);
 wait_on_recovery:
-	ret = nfs4_wait_clnt_recover(clp);
+	exception->recovering = 1;
+	return 0;
+}
+
+/* This is the error handling routine for processes that are allowed
+ * to sleep.
+ */
+int nfs4_handle_exception(struct nfs_server *server, int errorcode, struct nfs4_exception *exception)
+{
+	struct nfs_client *clp = server->nfs_client;
+	int ret;
+
+	ret = nfs4_do_handle_exception(server, errorcode, exception);
+	if (exception->delay) {
+		ret = nfs4_delay(server->client, &exception->timeout);
+		goto out_retry;
+	}
+	if (exception->recovering) {
+		ret = nfs4_wait_clnt_recover(clp);
+		if (test_bit(NFS_MIG_FAILED, &server->mig_status))
+			return -EIO;
+		goto out_retry;
+	}
+	return ret;
+out_retry:
+	if (ret == 0)
+		exception->retry = 1;
+	return ret;
+}
+
+static int
+nfs4_async_handle_exception(struct rpc_task *task, struct nfs_server *server,
+		int errorcode, struct nfs4_exception *exception)
+{
+	struct nfs_client *clp = server->nfs_client;
+	int ret;
+
+	ret = nfs4_do_handle_exception(server, errorcode, exception);
+	if (exception->delay) {
+		rpc_delay(task, nfs4_update_delay(&exception->timeout));
+		goto out_retry;
+	}
+	if (exception->recovering) {
+		rpc_sleep_on(&clp->cl_rpcwaitq, task, NULL);
+		if (test_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) == 0)
+			rpc_wake_up_queued_task(&clp->cl_rpcwaitq, task);
+		goto out_retry;
+	}
 	if (test_bit(NFS_MIG_FAILED, &server->mig_status))
-		return -EIO;
+		ret = -EIO;
+	return ret;
+out_retry:
 	if (ret == 0)
 		exception->retry = 1;
 	return ret;
 }
 
+static int
+nfs4_async_handle_error(struct rpc_task *task, struct nfs_server *server,
+			struct nfs4_state *state, long *timeout)
+{
+	struct nfs4_exception exception = {
+		.state = state,
+	};
+
+	if (task->tk_status >= 0)
+		return 0;
+	if (timeout)
+		exception.timeout = *timeout;
+	task->tk_status = nfs4_async_handle_exception(task, server,
+			task->tk_status,
+			&exception);
+	if (exception.delay && timeout)
+		*timeout = exception.timeout;
+	if (exception.retry)
+		return -EAGAIN;
+	return 0;
+}
+
 /*
  * Return 'true' if 'clp' is using an rpc_client that is integrity protected
  * or 'false' otherwise.
@@ -4530,7 +4603,7 @@ static inline int nfs4_server_supports_acls(struct nfs_server *server)
 #define NFS4ACL_MAXPAGES DIV_ROUND_UP(XATTR_SIZE_MAX, PAGE_SIZE)
 
 static int buf_to_pages_noslab(const void *buf, size_t buflen,
-		struct page **pages, unsigned int *pgbase)
+		struct page **pages)
 {
 	struct page *newpage, **spages;
 	int rc = 0;
@@ -4674,7 +4747,6 @@ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bu
 		goto out_free;
 
 	args.acl_len = npages * PAGE_SIZE;
-	args.acl_pgbase = 0;
 
 	dprintk("%s  buf %p buflen %zu npages %d args.acl_len %zu\n",
 		__func__, buf, buflen, npages, args.acl_len);
@@ -4766,7 +4838,7 @@ static int __nfs4_proc_set_acl(struct inode *inode, const void *buf, size_t bufl
 		return -EOPNOTSUPP;
 	if (npages > ARRAY_SIZE(pages))
 		return -ERANGE;
-	i = buf_to_pages_noslab(buf, buflen, arg.acl_pages, &arg.acl_pgbase);
+	i = buf_to_pages_noslab(buf, buflen, arg.acl_pages);
 	if (i < 0)
 		return i;
 	nfs4_inode_return_delegation(inode);
@@ -4955,79 +5027,6 @@ out:
 #endif	/* CONFIG_NFS_V4_SECURITY_LABEL */
 
 
-static int
-nfs4_async_handle_error(struct rpc_task *task, const struct nfs_server *server,
-			struct nfs4_state *state, long *timeout)
-{
-	struct nfs_client *clp = server->nfs_client;
-
-	if (task->tk_status >= 0)
-		return 0;
-	switch(task->tk_status) {
-		case -NFS4ERR_DELEG_REVOKED:
-		case -NFS4ERR_ADMIN_REVOKED:
-		case -NFS4ERR_BAD_STATEID:
-		case -NFS4ERR_OPENMODE:
-			if (state == NULL)
-				break;
-			if (nfs4_schedule_stateid_recovery(server, state) < 0)
-				goto recovery_failed;
-			goto wait_on_recovery;
-		case -NFS4ERR_EXPIRED:
-			if (state != NULL) {
-				if (nfs4_schedule_stateid_recovery(server, state) < 0)
-					goto recovery_failed;
-			}
-		case -NFS4ERR_STALE_STATEID:
-		case -NFS4ERR_STALE_CLIENTID:
-			nfs4_schedule_lease_recovery(clp);
-			goto wait_on_recovery;
-		case -NFS4ERR_MOVED:
-			if (nfs4_schedule_migration_recovery(server) < 0)
-				goto recovery_failed;
-			goto wait_on_recovery;
-		case -NFS4ERR_LEASE_MOVED:
-			nfs4_schedule_lease_moved_recovery(clp);
-			goto wait_on_recovery;
-#if defined(CONFIG_NFS_V4_1)
-		case -NFS4ERR_BADSESSION:
-		case -NFS4ERR_BADSLOT:
-		case -NFS4ERR_BAD_HIGH_SLOT:
-		case -NFS4ERR_DEADSESSION:
-		case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
-		case -NFS4ERR_SEQ_FALSE_RETRY:
-		case -NFS4ERR_SEQ_MISORDERED:
-			dprintk("%s ERROR %d, Reset session\n", __func__,
-				task->tk_status);
-			nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
-			goto wait_on_recovery;
-#endif /* CONFIG_NFS_V4_1 */
-		case -NFS4ERR_DELAY:
-			nfs_inc_server_stats(server, NFSIOS_DELAY);
-			rpc_delay(task, nfs4_update_delay(timeout));
-			goto restart_call;
-		case -NFS4ERR_GRACE:
-			rpc_delay(task, NFS4_POLL_RETRY_MAX);
-		case -NFS4ERR_RETRY_UNCACHED_REP:
-		case -NFS4ERR_OLD_STATEID:
-			goto restart_call;
-	}
-	task->tk_status = nfs4_map_errors(task->tk_status);
-	return 0;
-recovery_failed:
-	task->tk_status = -EIO;
-	return 0;
-wait_on_recovery:
-	rpc_sleep_on(&clp->cl_rpcwaitq, task, NULL);
-	if (test_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) == 0)
-		rpc_wake_up_queued_task(&clp->cl_rpcwaitq, task);
-	if (test_bit(NFS_MIG_FAILED, &server->mig_status))
-		goto recovery_failed;
-restart_call:
-	task->tk_status = 0;
-	return -EAGAIN;
-}
-
 static void nfs4_init_boot_verifier(const struct nfs_client *clp,
 				    nfs4_verifier *bootverf)
 {
@@ -5522,7 +5521,7 @@ struct nfs4_unlockdata {
 	struct nfs4_lock_state *lsp;
 	struct nfs_open_context *ctx;
 	struct file_lock fl;
-	const struct nfs_server *server;
+	struct nfs_server *server;
 	unsigned long timestamp;
 };
 
@@ -8718,7 +8717,8 @@ static const struct nfs4_minor_version_ops nfs_v4_2_minor_ops = {
 		| NFS_CAP_ALLOCATE
 		| NFS_CAP_DEALLOCATE
 		| NFS_CAP_SEEK
-		| NFS_CAP_LAYOUTSTATS,
+		| NFS_CAP_LAYOUTSTATS
+		| NFS_CAP_CLONE,
 	.init_client = nfs41_init_client,
 	.shutdown_client = nfs41_shutdown_client,
 	.match_stateid = nfs41_match_stateid,
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 788adf3..dfed4f5 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -1659,7 +1659,7 @@ encode_setacl(struct xdr_stream *xdr, struct nfs_setaclargs *arg, struct compoun
 	*p = cpu_to_be32(FATTR4_WORD0_ACL);
 	p = reserve_space(xdr, 4);
 	*p = cpu_to_be32(arg->acl_len);
-	xdr_write_pages(xdr, arg->acl_pages, arg->acl_pgbase, arg->acl_len);
+	xdr_write_pages(xdr, arg->acl_pages, 0, arg->acl_len);
 }
 
 static void
@@ -2491,7 +2491,7 @@ static void nfs4_xdr_enc_getacl(struct rpc_rqst *req, struct xdr_stream *xdr,
 	encode_getattr_two(xdr, FATTR4_WORD0_ACL, 0, &hdr);
 
 	xdr_inline_pages(&req->rq_rcv_buf, replen << 2,
-		args->acl_pages, args->acl_pgbase, args->acl_len);
+		args->acl_pages, 0, args->acl_len);
 
 	encode_nops(&hdr);
 }
@@ -4375,6 +4375,11 @@ static int decode_statfs(struct xdr_stream *xdr, struct nfs_fsstat *fsstat)
 		goto xdr_error;
 	if ((status = decode_attr_files_total(xdr, bitmap, &fsstat->tfiles)) != 0)
 		goto xdr_error;
+
+	status = -EIO;
+	if (unlikely(bitmap[0]))
+		goto xdr_error;
+
 	if ((status = decode_attr_space_avail(xdr, bitmap, &fsstat->abytes)) != 0)
 		goto xdr_error;
 	if ((status = decode_attr_space_free(xdr, bitmap, &fsstat->fbytes)) != 0)
@@ -4574,6 +4579,10 @@ static int decode_getfattr_attrs(struct xdr_stream *xdr, uint32_t *bitmap,
 		goto xdr_error;
 	fattr->valid |= status;
 
+	status = -EIO;
+	if (unlikely(bitmap[0]))
+		goto xdr_error;
+
 	status = decode_attr_mode(xdr, bitmap, &fmode);
 	if (status < 0)
 		goto xdr_error;
@@ -4627,6 +4636,10 @@ static int decode_getfattr_attrs(struct xdr_stream *xdr, uint32_t *bitmap,
 		goto xdr_error;
 	fattr->valid |= status;
 
+	status = -EIO;
+	if (unlikely(bitmap[1]))
+		goto xdr_error;
+
 	status = decode_attr_mdsthreshold(xdr, bitmap, fattr->mdsthreshold);
 	if (status < 0)
 		goto xdr_error;
@@ -4764,6 +4777,28 @@ static int decode_attr_layout_blksize(struct xdr_stream *xdr, uint32_t *bitmap,
 	return 0;
 }
 
+/*
+ * The granularity of a CLONE operation.
+ */
+static int decode_attr_clone_blksize(struct xdr_stream *xdr, uint32_t *bitmap,
+				     uint32_t *res)
+{
+	__be32 *p;
+
+	dprintk("%s: bitmap is %x\n", __func__, bitmap[2]);
+	*res = 0;
+	if (bitmap[2] & FATTR4_WORD2_CLONE_BLKSIZE) {
+		p = xdr_inline_decode(xdr, 4);
+		if (unlikely(!p)) {
+			print_overflow_msg(__func__, xdr);
+			return -EIO;
+		}
+		*res = be32_to_cpup(p);
+		bitmap[2] &= ~FATTR4_WORD2_CLONE_BLKSIZE;
+	}
+	return 0;
+}
+
 static int decode_fsinfo(struct xdr_stream *xdr, struct nfs_fsinfo *fsinfo)
 {
 	unsigned int savep;
@@ -4789,15 +4824,28 @@ static int decode_fsinfo(struct xdr_stream *xdr, struct nfs_fsinfo *fsinfo)
 	if ((status = decode_attr_maxwrite(xdr, bitmap, &fsinfo->wtmax)) != 0)
 		goto xdr_error;
 	fsinfo->wtpref = fsinfo->wtmax;
+
+	status = -EIO;
+	if (unlikely(bitmap[0]))
+		goto xdr_error;
+
 	status = decode_attr_time_delta(xdr, bitmap, &fsinfo->time_delta);
 	if (status != 0)
 		goto xdr_error;
 	status = decode_attr_pnfstype(xdr, bitmap, &fsinfo->layouttype);
 	if (status != 0)
 		goto xdr_error;
+
+	status = -EIO;
+	if (unlikely(bitmap[1]))
+		goto xdr_error;
+
 	status = decode_attr_layout_blksize(xdr, bitmap, &fsinfo->blksize);
 	if (status)
 		goto xdr_error;
+	status = decode_attr_clone_blksize(xdr, bitmap, &fsinfo->clone_blksize);
+	if (status)
+		goto xdr_error;
 
 	status = verify_attr_len(xdr, savep, attrlen);
 xdr_error:
@@ -7465,6 +7513,7 @@ struct rpc_procinfo	nfs4_procedures[] = {
 	PROC(ALLOCATE,		enc_allocate,		dec_allocate),
 	PROC(DEALLOCATE,	enc_deallocate,		dec_deallocate),
 	PROC(LAYOUTSTATS,	enc_layoutstats,	dec_layoutstats),
+	PROC(CLONE,		enc_clone,		dec_clone),
 #endif /* CONFIG_NFS_V4_2 */
 };
 
diff --git a/fs/nfs/nfsroot.c b/fs/nfs/nfsroot.c
index 9bc9f04..89a15db 100644
--- a/fs/nfs/nfsroot.c
+++ b/fs/nfs/nfsroot.c
@@ -90,7 +90,7 @@
 #define NFS_DEF_OPTIONS		"vers=2,udp,rsize=4096,wsize=4096"
 
 /* Parameters passed from the kernel command line */
-static char nfs_root_parms[256] __initdata = "";
+static char nfs_root_parms[NFS_MAXPATHLEN + 1] __initdata = "";
 
 /* Text-based mount options passed to super.c */
 static char nfs_root_options[256] __initdata = NFS_DEF_OPTIONS;
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 8abe271..93496c0 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -1912,12 +1912,13 @@ static void pnfs_ld_handle_write_error(struct nfs_pgio_header *hdr)
  */
 void pnfs_ld_write_done(struct nfs_pgio_header *hdr)
 {
-	trace_nfs4_pnfs_write(hdr, hdr->pnfs_error);
-	if (!hdr->pnfs_error) {
+	if (likely(!hdr->pnfs_error)) {
 		pnfs_set_layoutcommit(hdr->inode, hdr->lseg,
 				hdr->mds_offset + hdr->res.count);
 		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
-	} else
+	}
+	trace_nfs4_pnfs_write(hdr, hdr->pnfs_error);
+	if (unlikely(hdr->pnfs_error))
 		pnfs_ld_handle_write_error(hdr);
 	hdr->mds_ops->rpc_release(hdr);
 }
@@ -2028,11 +2029,12 @@ static void pnfs_ld_handle_read_error(struct nfs_pgio_header *hdr)
  */
 void pnfs_ld_read_done(struct nfs_pgio_header *hdr)
 {
-	trace_nfs4_pnfs_read(hdr, hdr->pnfs_error);
 	if (likely(!hdr->pnfs_error)) {
 		__nfs4_read_done_cb(hdr);
 		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
-	} else
+	}
+	trace_nfs4_pnfs_read(hdr, hdr->pnfs_error);
+	if (unlikely(hdr->pnfs_error))
 		pnfs_ld_handle_read_error(hdr);
 	hdr->mds_ops->rpc_release(hdr);
 }
diff --git a/fs/nfs/read.c b/fs/nfs/read.c
index 01b8cc8..0a5e33f 100644
--- a/fs/nfs/read.c
+++ b/fs/nfs/read.c
@@ -246,6 +246,13 @@ static void nfs_readpage_retry(struct rpc_task *task,
 		nfs_set_pgio_error(hdr, -EIO, argp->offset);
 		return;
 	}
+
+	/* For non rpc-based layout drivers, retry-through-MDS */
+	if (!task->tk_ops) {
+		hdr->pnfs_error = -EAGAIN;
+		return;
+	}
+
 	/* Yes, so retry the read at the end of the hdr */
 	hdr->mds_offset += resp->count;
 	argp->offset += resp->count;
@@ -268,7 +275,7 @@ static void nfs_readpage_result(struct rpc_task *task,
 			hdr->good_bytes = bound - hdr->io_start;
 		}
 		spin_unlock(&hdr->lock);
-	} else if (hdr->res.count != hdr->args.count)
+	} else if (hdr->res.count < hdr->args.count)
 		nfs_readpage_retry(task, hdr);
 }
 
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 383a027..f126828 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -2816,7 +2816,6 @@ out_invalid_transport_udp:
  * NFS client for backwards compatibility
  */
 unsigned int nfs_callback_set_tcpport;
-unsigned short nfs_callback_tcpport;
 /* Default cache timeout is 10 minutes */
 unsigned int nfs_idmap_cache_timeout = 600;
 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
@@ -2827,7 +2826,6 @@ char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
 bool recover_lost_locks = false;
 
 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
-EXPORT_SYMBOL_GPL(nfs_callback_tcpport);
 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
 EXPORT_SYMBOL_GPL(max_session_slots);
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 75ab762..7b93164 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -1505,6 +1505,13 @@ static void nfs_writeback_result(struct rpc_task *task,
 			task->tk_status = -EIO;
 			return;
 		}
+
+		/* For non rpc-based layout drivers, retry-through-MDS */
+		if (!task->tk_ops) {
+			hdr->pnfs_error = -EAGAIN;
+			return;
+		}
+
 		/* Was this an NFSv2 write or an NFSv3 stable write? */
 		if (resp->verf->committed != NFS_UNSTABLE) {
 			/* Resend from where the server left off */