Merge tag 'nfs-for-3.16-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

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

   - massive cleanup of the NFS read/write code by Anna and Dros
   - support multiple NFS read/write requests per page in order to deal
     with non-page aligned pNFS striping.  Also cleans up the r/wsize <
     page size code nicely.
   - stable fix for ensuring inode is declared uptodate only after all
     the attributes have been checked.
   - stable fix for a kernel Oops when remounting
   - NFS over RDMA client fixes
   - move the pNFS files layout driver into its own subdirectory"

* tag 'nfs-for-3.16-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (79 commits)
  NFS: populate ->net in mount data when remounting
  pnfs: fix lockup caused by pnfs_generic_pg_test
  NFSv4.1: Fix typo in dprintk
  NFSv4.1: Comment is now wrong and redundant to code
  NFS: Use raw_write_seqcount_begin/end int nfs4_reclaim_open_state
  xprtrdma: Disconnect on registration failure
  xprtrdma: Remove BUG_ON() call sites
  xprtrdma: Avoid deadlock when credit window is reset
  SUNRPC: Move congestion window constants to header file
  xprtrdma: Reset connection timeout after successful reconnect
  xprtrdma: Use macros for reconnection timeout constants
  xprtrdma: Allocate missing pagelist
  xprtrdma: Remove Tavor MTU setting
  xprtrdma: Ensure ia->ri_id->qp is not NULL when reconnecting
  xprtrdma: Reduce the number of hardway buffer allocations
  xprtrdma: Limit work done by completion handler
  xprtrmda: Reduce calls to ib_poll_cq() in completion handlers
  xprtrmda: Reduce lock contention in completion handlers
  xprtrdma: Split the completion queue
  xprtrdma: Make rpcrdma_ep_destroy() return void
  ...

29 files changed, 1316 insertions, 1203 deletions

diff --git a/fs/nfs/Makefile b/fs/nfs/Makefile
index 03192a66c143..4782e0840dcc 100644
--- a/fs/nfs/Makefile
+++ b/fs/nfs/Makefile
@@ -29,8 +29,6 @@ nfsv4-$(CONFIG_NFS_USE_LEGACY_DNS) += cache_lib.o
 nfsv4-$(CONFIG_SYSCTL)	+= nfs4sysctl.o
 nfsv4-$(CONFIG_NFS_V4_1)	+= pnfs.o pnfs_dev.o
 
-obj-$(CONFIG_PNFS_FILE_LAYOUT) += nfs_layout_nfsv41_files.o
-nfs_layout_nfsv41_files-y := nfs4filelayout.o nfs4filelayoutdev.o
-
+obj-$(CONFIG_PNFS_FILE_LAYOUT) += filelayout/
 obj-$(CONFIG_PNFS_OBJLAYOUT) += objlayout/
 obj-$(CONFIG_PNFS_BLOCK) += blocklayout/
diff --git a/fs/nfs/blocklayout/blocklayout.c b/fs/nfs/blocklayout/blocklayout.c
index 65d849bdf77a..9b431f44fad9 100644
--- a/fs/nfs/blocklayout/blocklayout.c
+++ b/fs/nfs/blocklayout/blocklayout.c
@@ -210,7 +210,7 @@ static void bl_end_io_read(struct bio *bio, int err)
 			SetPageUptodate(bvec->bv_page);
 
 	if (err) {
-		struct nfs_read_data *rdata = par->data;
+		struct nfs_pgio_data *rdata = par->data;
 		struct nfs_pgio_header *header = rdata->header;
 
 		if (!header->pnfs_error)
@@ -224,17 +224,17 @@ static void bl_end_io_read(struct bio *bio, int err)
 static void bl_read_cleanup(struct work_struct *work)
 {
 	struct rpc_task *task;
-	struct nfs_read_data *rdata;
+	struct nfs_pgio_data *rdata;
 	dprintk("%s enter\n", __func__);
 	task = container_of(work, struct rpc_task, u.tk_work);
-	rdata = container_of(task, struct nfs_read_data, task);
+	rdata = container_of(task, struct nfs_pgio_data, task);
 	pnfs_ld_read_done(rdata);
 }
 
 static void
 bl_end_par_io_read(void *data, int unused)
 {
-	struct nfs_read_data *rdata = data;
+	struct nfs_pgio_data *rdata = data;
 
 	rdata->task.tk_status = rdata->header->pnfs_error;
 	INIT_WORK(&rdata->task.u.tk_work, bl_read_cleanup);
@@ -242,7 +242,7 @@ bl_end_par_io_read(void *data, int unused)
 }
 
 static enum pnfs_try_status
-bl_read_pagelist(struct nfs_read_data *rdata)
+bl_read_pagelist(struct nfs_pgio_data *rdata)
 {
 	struct nfs_pgio_header *header = rdata->header;
 	int i, hole;
@@ -390,7 +390,7 @@ static void bl_end_io_write_zero(struct bio *bio, int err)
 	}
 
 	if (unlikely(err)) {
-		struct nfs_write_data *data = par->data;
+		struct nfs_pgio_data *data = par->data;
 		struct nfs_pgio_header *header = data->header;
 
 		if (!header->pnfs_error)
@@ -405,7 +405,7 @@ static void bl_end_io_write(struct bio *bio, int err)
 {
 	struct parallel_io *par = bio->bi_private;
 	const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
-	struct nfs_write_data *data = par->data;
+	struct nfs_pgio_data *data = par->data;
 	struct nfs_pgio_header *header = data->header;
 
 	if (!uptodate) {
@@ -423,10 +423,10 @@ static void bl_end_io_write(struct bio *bio, int err)
 static void bl_write_cleanup(struct work_struct *work)
 {
 	struct rpc_task *task;
-	struct nfs_write_data *wdata;
+	struct nfs_pgio_data *wdata;
 	dprintk("%s enter\n", __func__);
 	task = container_of(work, struct rpc_task, u.tk_work);
-	wdata = container_of(task, struct nfs_write_data, task);
+	wdata = container_of(task, struct nfs_pgio_data, task);
 	if (likely(!wdata->header->pnfs_error)) {
 		/* Marks for LAYOUTCOMMIT */
 		mark_extents_written(BLK_LSEG2EXT(wdata->header->lseg),
@@ -438,7 +438,7 @@ static void bl_write_cleanup(struct work_struct *work)
 /* Called when last of bios associated with a bl_write_pagelist call finishes */
 static void bl_end_par_io_write(void *data, int num_se)
 {
-	struct nfs_write_data *wdata = data;
+	struct nfs_pgio_data *wdata = data;
 
 	if (unlikely(wdata->header->pnfs_error)) {
 		bl_free_short_extents(&BLK_LSEG2EXT(wdata->header->lseg)->bl_inval,
@@ -673,7 +673,7 @@ check_page:
 }
 
 static enum pnfs_try_status
-bl_write_pagelist(struct nfs_write_data *wdata, int sync)
+bl_write_pagelist(struct nfs_pgio_data *wdata, int sync)
 {
 	struct nfs_pgio_header *header = wdata->header;
 	int i, ret, npg_zero, pg_index, last = 0;
@@ -1189,13 +1189,17 @@ bl_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
 		pnfs_generic_pg_init_read(pgio, req);
 }
 
-static bool
+/*
+ * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
+ * of bytes (maximum @req->wb_bytes) that can be coalesced.
+ */
+static size_t
 bl_pg_test_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
 		struct nfs_page *req)
 {
 	if (pgio->pg_dreq != NULL &&
 	    !is_aligned_req(req, SECTOR_SIZE))
-		return false;
+		return 0;
 
 	return pnfs_generic_pg_test(pgio, prev, req);
 }
@@ -1241,13 +1245,17 @@ bl_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
 	}
 }
 
-static bool
+/*
+ * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
+ * of bytes (maximum @req->wb_bytes) that can be coalesced.
+ */
+static size_t
 bl_pg_test_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
 		 struct nfs_page *req)
 {
 	if (pgio->pg_dreq != NULL &&
 	    !is_aligned_req(req, PAGE_CACHE_SIZE))
-		return false;
+		return 0;
 
 	return pnfs_generic_pg_test(pgio, prev, req);
 }
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index b8797ae6831f..4ad7bc388679 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -108,6 +108,97 @@ static inline int put_dreq(struct nfs_direct_req *dreq)
 	return atomic_dec_and_test(&dreq->io_count);
 }
 
+/*
+ * nfs_direct_select_verf - select the right verifier
+ * @dreq - direct request possibly spanning multiple servers
+ * @ds_clp - nfs_client of data server or NULL if MDS / non-pnfs
+ * @ds_idx - index of data server in data server list, only valid if ds_clp set
+ *
+ * returns the correct verifier to use given the role of the server
+ */
+static struct nfs_writeverf *
+nfs_direct_select_verf(struct nfs_direct_req *dreq,
+		       struct nfs_client *ds_clp,
+		       int ds_idx)
+{
+	struct nfs_writeverf *verfp = &dreq->verf;
+
+#ifdef CONFIG_NFS_V4_1
+	if (ds_clp) {
+		/* pNFS is in use, use the DS verf */
+		if (ds_idx >= 0 && ds_idx < dreq->ds_cinfo.nbuckets)
+			verfp = &dreq->ds_cinfo.buckets[ds_idx].direct_verf;
+		else
+			WARN_ON_ONCE(1);
+	}
+#endif
+	return verfp;
+}
+
+
+/*
+ * nfs_direct_set_hdr_verf - set the write/commit verifier
+ * @dreq - direct request possibly spanning multiple servers
+ * @hdr - pageio header to validate against previously seen verfs
+ *
+ * Set the server's (MDS or DS) "seen" verifier
+ */
+static void nfs_direct_set_hdr_verf(struct nfs_direct_req *dreq,
+				    struct nfs_pgio_header *hdr)
+{
+	struct nfs_writeverf *verfp;
+
+	verfp = nfs_direct_select_verf(dreq, hdr->data->ds_clp,
+				      hdr->data->ds_idx);
+	WARN_ON_ONCE(verfp->committed >= 0);
+	memcpy(verfp, &hdr->verf, sizeof(struct nfs_writeverf));
+	WARN_ON_ONCE(verfp->committed < 0);
+}
+
+/*
+ * nfs_direct_cmp_hdr_verf - compare verifier for pgio header
+ * @dreq - direct request possibly spanning multiple servers
+ * @hdr - pageio header to validate against previously seen verf
+ *
+ * set the server's "seen" verf if not initialized.
+ * returns result of comparison between @hdr->verf and the "seen"
+ * verf of the server used by @hdr (DS or MDS)
+ */
+static int nfs_direct_set_or_cmp_hdr_verf(struct nfs_direct_req *dreq,
+					  struct nfs_pgio_header *hdr)
+{
+	struct nfs_writeverf *verfp;
+
+	verfp = nfs_direct_select_verf(dreq, hdr->data->ds_clp,
+					 hdr->data->ds_idx);
+	if (verfp->committed < 0) {
+		nfs_direct_set_hdr_verf(dreq, hdr);
+		return 0;
+	}
+	return memcmp(verfp, &hdr->verf, sizeof(struct nfs_writeverf));
+}
+
+#if IS_ENABLED(CONFIG_NFS_V3) || IS_ENABLED(CONFIG_NFS_V4)
+/*
+ * nfs_direct_cmp_commit_data_verf - compare verifier for commit data
+ * @dreq - direct request possibly spanning multiple servers
+ * @data - commit data to validate against previously seen verf
+ *
+ * returns result of comparison between @data->verf and the verf of
+ * the server used by @data (DS or MDS)
+ */
+static int nfs_direct_cmp_commit_data_verf(struct nfs_direct_req *dreq,
+					   struct nfs_commit_data *data)
+{
+	struct nfs_writeverf *verfp;
+
+	verfp = nfs_direct_select_verf(dreq, data->ds_clp,
+					 data->ds_commit_index);
+	WARN_ON_ONCE(verfp->committed < 0);
+	return memcmp(verfp, &data->verf, sizeof(struct nfs_writeverf));
+}
+#endif
+
 /**
  * nfs_direct_IO - NFS address space operation for direct I/O
  * @rw: direction (read or write)
@@ -168,6 +259,7 @@ static inline struct nfs_direct_req *nfs_direct_req_alloc(void)
 	kref_get(&dreq->kref);
 	init_completion(&dreq->completion);
 	INIT_LIST_HEAD(&dreq->mds_cinfo.list);
+	dreq->verf.committed = NFS_INVALID_STABLE_HOW;	/* not set yet */
 	INIT_WORK(&dreq->work, nfs_direct_write_schedule_work);
 	spin_lock_init(&dreq->lock);
 
@@ -380,8 +472,7 @@ static ssize_t nfs_direct_read_schedule_segment(struct nfs_pageio_descriptor *de
 			struct nfs_page *req;
 			unsigned int req_len = min_t(size_t, bytes, PAGE_SIZE - pgbase);
 			/* XXX do we need to do the eof zeroing found in async_filler? */
-			req = nfs_create_request(dreq->ctx, dreq->inode,
-						 pagevec[i],
+			req = nfs_create_request(dreq->ctx, pagevec[i], NULL,
 						 pgbase, req_len);
 			if (IS_ERR(req)) {
 				result = PTR_ERR(req);
@@ -424,7 +515,7 @@ static ssize_t nfs_direct_read_schedule_iovec(struct nfs_direct_req *dreq,
 	size_t requested_bytes = 0;
 	unsigned long seg;
 
-	NFS_PROTO(dreq->inode)->read_pageio_init(&desc, dreq->inode,
+	nfs_pageio_init_read(&desc, dreq->inode, false,
 			     &nfs_direct_read_completion_ops);
 	get_dreq(dreq);
 	desc.pg_dreq = dreq;
@@ -564,7 +655,7 @@ static void nfs_direct_write_reschedule(struct nfs_direct_req *dreq)
 	dreq->count = 0;
 	get_dreq(dreq);
 
-	NFS_PROTO(dreq->inode)->write_pageio_init(&desc, dreq->inode, FLUSH_STABLE,
+	nfs_pageio_init_write(&desc, dreq->inode, FLUSH_STABLE, false,
 			      &nfs_direct_write_completion_ops);
 	desc.pg_dreq = dreq;
 
@@ -603,7 +694,7 @@ static void nfs_direct_commit_complete(struct nfs_commit_data *data)
 		dprintk("NFS: %5u commit failed with error %d.\n",
 			data->task.tk_pid, status);
 		dreq->flags = NFS_ODIRECT_RESCHED_WRITES;
-	} else if (memcmp(&dreq->verf, &data->verf, sizeof(data->verf))) {
+	} else if (nfs_direct_cmp_commit_data_verf(dreq, data)) {
 		dprintk("NFS: %5u commit verify failed\n", data->task.tk_pid);
 		dreq->flags = NFS_ODIRECT_RESCHED_WRITES;
 	}
@@ -750,8 +841,7 @@ static ssize_t nfs_direct_write_schedule_segment(struct nfs_pageio_descriptor *d
 			struct nfs_page *req;
 			unsigned int req_len = min_t(size_t, bytes, PAGE_SIZE - pgbase);
 
-			req = nfs_create_request(dreq->ctx, dreq->inode,
-						 pagevec[i],
+			req = nfs_create_request(dreq->ctx, pagevec[i], NULL,
 						 pgbase, req_len);
 			if (IS_ERR(req)) {
 				result = PTR_ERR(req);
@@ -813,13 +903,13 @@ static void nfs_direct_write_completion(struct nfs_pgio_header *hdr)
 			if (dreq->flags == NFS_ODIRECT_RESCHED_WRITES)
 				bit = NFS_IOHDR_NEED_RESCHED;
 			else if (dreq->flags == 0) {
-				memcpy(&dreq->verf, hdr->verf,
-				       sizeof(dreq->verf));
+				nfs_direct_set_hdr_verf(dreq, hdr);
 				bit = NFS_IOHDR_NEED_COMMIT;
 				dreq->flags = NFS_ODIRECT_DO_COMMIT;
 			} else if (dreq->flags == NFS_ODIRECT_DO_COMMIT) {
-				if (memcmp(&dreq->verf, hdr->verf, sizeof(dreq->verf))) {
-					dreq->flags = NFS_ODIRECT_RESCHED_WRITES;
+				if (nfs_direct_set_or_cmp_hdr_verf(dreq, hdr)) {
+					dreq->flags =
+						NFS_ODIRECT_RESCHED_WRITES;
 					bit = NFS_IOHDR_NEED_RESCHED;
 				} else
 					bit = NFS_IOHDR_NEED_COMMIT;
@@ -829,6 +919,8 @@ static void nfs_direct_write_completion(struct nfs_pgio_header *hdr)
 	spin_unlock(&dreq->lock);
 
 	while (!list_empty(&hdr->pages)) {
+		bool do_destroy = true;
+
 		req = nfs_list_entry(hdr->pages.next);
 		nfs_list_remove_request(req);
 		switch (bit) {
@@ -836,6 +928,7 @@ static void nfs_direct_write_completion(struct nfs_pgio_header *hdr)
 		case NFS_IOHDR_NEED_COMMIT:
 			kref_get(&req->wb_kref);
 			nfs_mark_request_commit(req, hdr->lseg, &cinfo);
+			do_destroy = false;
 		}
 		nfs_unlock_and_release_request(req);
 	}
@@ -874,7 +967,7 @@ static ssize_t nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq,
 	size_t requested_bytes = 0;
 	unsigned long seg;
 
-	NFS_PROTO(inode)->write_pageio_init(&desc, inode, FLUSH_COND_STABLE,
+	nfs_pageio_init_write(&desc, inode, FLUSH_COND_STABLE, false,
 			      &nfs_direct_write_completion_ops);
 	desc.pg_dreq = dreq;
 	get_dreq(dreq);
diff --git a/fs/nfs/filelayout/Makefile b/fs/nfs/filelayout/Makefile
new file mode 100644
index 000000000000..8516cdffb9e9
--- /dev/null
+++ b/fs/nfs/filelayout/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for the pNFS Files Layout Driver kernel module
+#
+obj-$(CONFIG_PNFS_FILE_LAYOUT) += nfs_layout_nfsv41_files.o
+nfs_layout_nfsv41_files-y := filelayout.o filelayoutdev.o
diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/filelayout/filelayout.c
index b9a35c05b60f..d2eba1c13b7e 100644
--- a/fs/nfs/nfs4filelayout.c
+++ b/fs/nfs/filelayout/filelayout.c
@@ -35,11 +35,11 @@
 
 #include <linux/sunrpc/metrics.h>
 
-#include "nfs4session.h"
-#include "internal.h"
-#include "delegation.h"
-#include "nfs4filelayout.h"
-#include "nfs4trace.h"
+#include "../nfs4session.h"
+#include "../internal.h"
+#include "../delegation.h"
+#include "filelayout.h"
+#include "../nfs4trace.h"
 
 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
 
@@ -84,7 +84,7 @@ filelayout_get_dserver_offset(struct pnfs_layout_segment *lseg, loff_t offset)
 	BUG();
 }
 
-static void filelayout_reset_write(struct nfs_write_data *data)
+static void filelayout_reset_write(struct nfs_pgio_data *data)
 {
 	struct nfs_pgio_header *hdr = data->header;
 	struct rpc_task *task = &data->task;
@@ -105,7 +105,7 @@ static void filelayout_reset_write(struct nfs_write_data *data)
 	}
 }
 
-static void filelayout_reset_read(struct nfs_read_data *data)
+static void filelayout_reset_read(struct nfs_pgio_data *data)
 {
 	struct nfs_pgio_header *hdr = data->header;
 	struct rpc_task *task = &data->task;
@@ -243,7 +243,7 @@ wait_on_recovery:
 /* NFS_PROTO call done callback routines */
 
 static int filelayout_read_done_cb(struct rpc_task *task,
-				struct nfs_read_data *data)
+				struct nfs_pgio_data *data)
 {
 	struct nfs_pgio_header *hdr = data->header;
 	int err;
@@ -270,7 +270,7 @@ static int filelayout_read_done_cb(struct rpc_task *task,
  * rfc5661 is not clear about which credential should be used.
  */
 static void
-filelayout_set_layoutcommit(struct nfs_write_data *wdata)
+filelayout_set_layoutcommit(struct nfs_pgio_data *wdata)
 {
 	struct nfs_pgio_header *hdr = wdata->header;
 
@@ -279,7 +279,7 @@ filelayout_set_layoutcommit(struct nfs_write_data *wdata)
 		return;
 
 	pnfs_set_layoutcommit(wdata);
-	dprintk("%s ionde %lu pls_end_pos %lu\n", __func__, hdr->inode->i_ino,
+	dprintk("%s inode %lu pls_end_pos %lu\n", __func__, hdr->inode->i_ino,
 		(unsigned long) NFS_I(hdr->inode)->layout->plh_lwb);
 }
 
@@ -305,7 +305,7 @@ filelayout_reset_to_mds(struct pnfs_layout_segment *lseg)
  */
 static void filelayout_read_prepare(struct rpc_task *task, void *data)
 {
-	struct nfs_read_data *rdata = data;
+	struct nfs_pgio_data *rdata = data;
 
 	if (unlikely(test_bit(NFS_CONTEXT_BAD, &rdata->args.context->flags))) {
 		rpc_exit(task, -EIO);
@@ -317,7 +317,7 @@ static void filelayout_read_prepare(struct rpc_task *task, void *data)
 		rpc_exit(task, 0);
 		return;
 	}
-	rdata->read_done_cb = filelayout_read_done_cb;
+	rdata->pgio_done_cb = filelayout_read_done_cb;
 
 	if (nfs41_setup_sequence(rdata->ds_clp->cl_session,
 			&rdata->args.seq_args,
@@ -331,7 +331,7 @@ static void filelayout_read_prepare(struct rpc_task *task, void *data)
 
 static void filelayout_read_call_done(struct rpc_task *task, void *data)
 {
-	struct nfs_read_data *rdata = data;
+	struct nfs_pgio_data *rdata = data;
 
 	dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
 
@@ -347,14 +347,14 @@ static void filelayout_read_call_done(struct rpc_task *task, void *data)
 
 static void filelayout_read_count_stats(struct rpc_task *task, void *data)
 {
-	struct nfs_read_data *rdata = data;
+	struct nfs_pgio_data *rdata = data;
 
 	rpc_count_iostats(task, NFS_SERVER(rdata->header->inode)->client->cl_metrics);
 }
 
 static void filelayout_read_release(void *data)
 {
-	struct nfs_read_data *rdata = data;
+	struct nfs_pgio_data *rdata = data;
 	struct pnfs_layout_hdr *lo = rdata->header->lseg->pls_layout;
 
 	filelayout_fenceme(lo->plh_inode, lo);
@@ -363,7 +363,7 @@ static void filelayout_read_release(void *data)
 }
 
 static int filelayout_write_done_cb(struct rpc_task *task,
-				struct nfs_write_data *data)
+				struct nfs_pgio_data *data)
 {
 	struct nfs_pgio_header *hdr = data->header;
 	int err;
@@ -419,7 +419,7 @@ static int filelayout_commit_done_cb(struct rpc_task *task,
 
 static void filelayout_write_prepare(struct rpc_task *task, void *data)
 {
-	struct nfs_write_data *wdata = data;
+	struct nfs_pgio_data *wdata = data;
 
 	if (unlikely(test_bit(NFS_CONTEXT_BAD, &wdata->args.context->flags))) {
 		rpc_exit(task, -EIO);
@@ -443,7 +443,7 @@ static void filelayout_write_prepare(struct rpc_task *task, void *data)
 
 static void filelayout_write_call_done(struct rpc_task *task, void *data)
 {
-	struct nfs_write_data *wdata = data;
+	struct nfs_pgio_data *wdata = data;
 
 	if (test_bit(NFS_IOHDR_REDO, &wdata->header->flags) &&
 	    task->tk_status == 0) {
@@ -457,14 +457,14 @@ static void filelayout_write_call_done(struct rpc_task *task, void *data)
 
 static void filelayout_write_count_stats(struct rpc_task *task, void *data)
 {
-	struct nfs_write_data *wdata = data;
+	struct nfs_pgio_data *wdata = data;
 
 	rpc_count_iostats(task, NFS_SERVER(wdata->header->inode)->client->cl_metrics);
 }
 
 static void filelayout_write_release(void *data)
 {
-	struct nfs_write_data *wdata = data;
+	struct nfs_pgio_data *wdata = data;
 	struct pnfs_layout_hdr *lo = wdata->header->lseg->pls_layout;
 
 	filelayout_fenceme(lo->plh_inode, lo);
@@ -529,7 +529,7 @@ static const struct rpc_call_ops filelayout_commit_call_ops = {
 };
 
 static enum pnfs_try_status
-filelayout_read_pagelist(struct nfs_read_data *data)
+filelayout_read_pagelist(struct nfs_pgio_data *data)
 {
 	struct nfs_pgio_header *hdr = data->header;
 	struct pnfs_layout_segment *lseg = hdr->lseg;
@@ -560,6 +560,7 @@ filelayout_read_pagelist(struct nfs_read_data *data)
 	/* No multipath support. Use first DS */
 	atomic_inc(&ds->ds_clp->cl_count);
 	data->ds_clp = ds->ds_clp;
+	data->ds_idx = idx;
 	fh = nfs4_fl_select_ds_fh(lseg, j);
 	if (fh)
 		data->args.fh = fh;
@@ -568,14 +569,14 @@ filelayout_read_pagelist(struct nfs_read_data *data)
 	data->mds_offset = offset;
 
 	/* Perform an asynchronous read to ds */
-	nfs_initiate_read(ds_clnt, data,
-				  &filelayout_read_call_ops, RPC_TASK_SOFTCONN);
+	nfs_initiate_pgio(ds_clnt, data,
+			    &filelayout_read_call_ops, 0, RPC_TASK_SOFTCONN);
 	return PNFS_ATTEMPTED;
 }
 
 /* Perform async writes. */
 static enum pnfs_try_status
-filelayout_write_pagelist(struct nfs_write_data *data, int sync)
+filelayout_write_pagelist(struct nfs_pgio_data *data, int sync)
 {
 	struct nfs_pgio_header *hdr = data->header;
 	struct pnfs_layout_segment *lseg = hdr->lseg;
@@ -600,20 +601,18 @@ filelayout_write_pagelist(struct nfs_write_data *data, int sync)
 		__func__, hdr->inode->i_ino, sync, (size_t) data->args.count,
 		offset, ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count));
 
-	data->write_done_cb = filelayout_write_done_cb;
+	data->pgio_done_cb = filelayout_write_done_cb;
 	atomic_inc(&ds->ds_clp->cl_count);
 	data->ds_clp = ds->ds_clp;
+	data->ds_idx = idx;
 	fh = nfs4_fl_select_ds_fh(lseg, j);
 	if (fh)
 		data->args.fh = fh;
-	/*
-	 * Get the file offset on the dserver. Set the write offset to
-	 * this offset and save the original offset.
-	 */
+
 	data->args.offset = filelayout_get_dserver_offset(lseg, offset);
 
 	/* Perform an asynchronous write */
-	nfs_initiate_write(ds_clnt, data,
+	nfs_initiate_pgio(ds_clnt, data,
 				    &filelayout_write_call_ops, sync,
 				    RPC_TASK_SOFTCONN);
 	return PNFS_ATTEMPTED;
@@ -637,7 +636,6 @@ filelayout_check_layout(struct pnfs_layout_hdr *lo,
 	struct nfs4_deviceid_node *d;
 	struct nfs4_file_layout_dsaddr *dsaddr;
 	int status = -EINVAL;
-	struct nfs_server *nfss = NFS_SERVER(lo->plh_inode);
 
 	dprintk("--> %s\n", __func__);
 
@@ -655,7 +653,7 @@ filelayout_check_layout(struct pnfs_layout_hdr *lo,
 		goto out;
 	}
 
-	if (!fl->stripe_unit || fl->stripe_unit % PAGE_SIZE) {
+	if (!fl->stripe_unit) {
 		dprintk("%s Invalid stripe unit (%u)\n",
 			__func__, fl->stripe_unit);
 		goto out;
@@ -692,12 +690,6 @@ filelayout_check_layout(struct pnfs_layout_hdr *lo,
 		goto out_put;
 	}
 
-	if (fl->stripe_unit % nfss->rsize || fl->stripe_unit % nfss->wsize) {
-		dprintk("%s Stripe unit (%u) not aligned with rsize %u "
-			"wsize %u\n", __func__, fl->stripe_unit, nfss->rsize,
-			nfss->wsize);
-	}
-
 	status = 0;
 out:
 	dprintk("--> %s returns %d\n", __func__, status);
@@ -850,11 +842,15 @@ filelayout_alloc_commit_info(struct pnfs_layout_segment *lseg,
 {
 	struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 	struct pnfs_commit_bucket *buckets;
-	int size;
+	int size, i;
 
 	if (fl->commit_through_mds)
 		return 0;
-	if (cinfo->ds->nbuckets != 0) {
+
+	size = (fl->stripe_type == STRIPE_SPARSE) ?
+		fl->dsaddr->ds_num : fl->dsaddr->stripe_count;
+
+	if (cinfo->ds->nbuckets >= size) {
 		/* This assumes there is only one IOMODE_RW lseg.  What
 		 * we really want to do is have a layout_hdr level
 		 * dictionary of <multipath_list4, fh> keys, each
@@ -864,30 +860,36 @@ filelayout_alloc_commit_info(struct pnfs_layout_segment *lseg,
 		return 0;
 	}
 
-	size = (fl->stripe_type == STRIPE_SPARSE) ?
-		fl->dsaddr->ds_num : fl->dsaddr->stripe_count;
-
 	buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
 			  gfp_flags);
 	if (!buckets)
 		return -ENOMEM;
-	else {
-		int i;
+	for (i = 0; i < size; i++) {
+		INIT_LIST_HEAD(&buckets[i].written);
+		INIT_LIST_HEAD(&buckets[i].committing);
+		/* mark direct verifier as unset */
+		buckets[i].direct_verf.committed = NFS_INVALID_STABLE_HOW;
+	}
 
-		spin_lock(cinfo->lock);
-		if (cinfo->ds->nbuckets != 0)
-			kfree(buckets);
-		else {
-			cinfo->ds->buckets = buckets;
-			cinfo->ds->nbuckets = size;
-			for (i = 0; i < size; i++) {
-				INIT_LIST_HEAD(&buckets[i].written);
-				INIT_LIST_HEAD(&buckets[i].committing);
-			}
-		}
-		spin_unlock(cinfo->lock);
-		return 0;
+	spin_lock(cinfo->lock);
+	if (cinfo->ds->nbuckets >= size)
+		goto out;
+	for (i = 0; i < cinfo->ds->nbuckets; i++) {
+		list_splice(&cinfo->ds->buckets[i].written,
+			    &buckets[i].written);
+		list_splice(&cinfo->ds->buckets[i].committing,
+			    &buckets[i].committing);
+		buckets[i].direct_verf.committed =
+			cinfo->ds->buckets[i].direct_verf.committed;
+		buckets[i].wlseg = cinfo->ds->buckets[i].wlseg;
+		buckets[i].clseg = cinfo->ds->buckets[i].clseg;
 	}
+	swap(cinfo->ds->buckets, buckets);
+	cinfo->ds->nbuckets = size;
+out:
+	spin_unlock(cinfo->lock);
+	kfree(buckets);
+	return 0;
 }
 
 static struct pnfs_layout_segment *
@@ -915,47 +917,51 @@ filelayout_alloc_lseg(struct pnfs_layout_hdr *layoutid,
 /*
  * filelayout_pg_test(). Called by nfs_can_coalesce_requests()
  *
- * return true  : coalesce page
- * return false : don't coalesce page
+ * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
+ * of bytes (maximum @req->wb_bytes) that can be coalesced.
  */
-static bool
+static size_t
 filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
 		   struct nfs_page *req)
 {
+	unsigned int size;
 	u64 p_stripe, r_stripe;
-	u32 stripe_unit;
+	u32 stripe_offset;
+	u64 segment_offset = pgio->pg_lseg->pls_range.offset;
+	u32 stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
 
-	if (!pnfs_generic_pg_test(pgio, prev, req) ||
-	    !nfs_generic_pg_test(pgio, prev, req))
-		return false;
+	/* calls nfs_generic_pg_test */
+	size = pnfs_generic_pg_test(pgio, prev, req);
+	if (!size)
+		return 0;
 
-	p_stripe = (u64)req_offset(prev);
-	r_stripe = (u64)req_offset(req);
-	stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
+	/* see if req and prev are in the same stripe */
+	if (prev) {
+		p_stripe = (u64)req_offset(prev) - segment_offset;
+		r_stripe = (u64)req_offset(req) - segment_offset;
+		do_div(p_stripe, stripe_unit);
+		do_div(r_stripe, stripe_unit);
 
-	do_div(p_stripe, stripe_unit);
-	do_div(r_stripe, stripe_unit);
+		if (p_stripe != r_stripe)
+			return 0;
+	}
 
-	return (p_stripe == r_stripe);
+	/* calculate remaining bytes in the current stripe */
+	div_u64_rem((u64)req_offset(req) - segment_offset,
+			stripe_unit,
+			&stripe_offset);
+	WARN_ON_ONCE(stripe_offset > stripe_unit);
+	if (stripe_offset >= stripe_unit)
+		return 0;
+	return min(stripe_unit - (unsigned int)stripe_offset, size);
 }
 
 static void
 filelayout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 			struct nfs_page *req)
 {
-	WARN_ON_ONCE(pgio->pg_lseg != NULL);
-
-	if (req->wb_offset != req->wb_pgbase) {
-		/*
-		 * Handling unaligned pages is difficult, because have to
-		 * somehow split a req in two in certain cases in the
-		 * pg.test code.  Avoid this by just not using pnfs
-		 * in this case.
-		 */
-		nfs_pageio_reset_read_mds(pgio);
-		return;
-	}
-	pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
+	if (!pgio->pg_lseg)
+		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 					   req->wb_context,
 					   0,
 					   NFS4_MAX_UINT64,
@@ -973,11 +979,8 @@ filelayout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 	struct nfs_commit_info cinfo;
 	int status;
 
-	WARN_ON_ONCE(pgio->pg_lseg != NULL);
-
-	if (req->wb_offset != req->wb_pgbase)
-		goto out_mds;
-	pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
+	if (!pgio->pg_lseg)
+		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 					   req->wb_context,
 					   0,
 					   NFS4_MAX_UINT64,
@@ -1067,6 +1070,7 @@ filelayout_choose_commit_list(struct nfs_page *req,
 	 */
 	j = nfs4_fl_calc_j_index(lseg, req_offset(req));
 	i = select_bucket_index(fl, j);
+	spin_lock(cinfo->lock);
 	buckets = cinfo->ds->buckets;
 	list = &buckets[i].written;
 	if (list_empty(list)) {
@@ -1080,6 +1084,7 @@ filelayout_choose_commit_list(struct nfs_page *req,
 	}
 	set_bit(PG_COMMIT_TO_DS, &req->wb_flags);
 	cinfo->ds->nwritten++;
+	spin_unlock(cinfo->lock);
 	return list;
 }
 
@@ -1176,6 +1181,7 @@ transfer_commit_list(struct list_head *src, struct list_head *dst,
 	return ret;
 }
 
+/* Note called with cinfo->lock held. */
 static int
 filelayout_scan_ds_commit_list(struct pnfs_commit_bucket *bucket,
 			       struct nfs_commit_info *cinfo,
@@ -1220,15 +1226,18 @@ static void filelayout_recover_commit_reqs(struct list_head *dst,
 					   struct nfs_commit_info *cinfo)
 {
 	struct pnfs_commit_bucket *b;
+	struct pnfs_layout_segment *freeme;