Push the file layout driver into a subdirectory

The object and block layouts already exist in their own
subdirectories. This patch completes the set!

Note that as a layout denotes nfs4 already, I stripped
that prefix out of the file names.

Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
Acked-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

1 files changed, 1409 insertions, 0 deletions

diff --git a/fs/nfs/filelayout/filelayout.c b/fs/nfs/filelayout/filelayout.c
new file mode 100644
index 000000000000..a008e8590417
--- /dev/null
+++ b/fs/nfs/filelayout/filelayout.c
@@ -0,0 +1,1409 @@
+/*
+ *  Module for the pnfs nfs4 file layout driver.
+ *  Defines all I/O and Policy interface operations, plus code
+ *  to register itself with the pNFS client.
+ *
+ *  Copyright (c) 2002
+ *  The Regents of the University of Michigan
+ *  All Rights Reserved
+ *
+ *  Dean Hildebrand <dhildebz@umich.edu>
+ *
+ *  Permission is granted to use, copy, create derivative works, and
+ *  redistribute this software and such derivative works for any purpose,
+ *  so long as the name of the University of Michigan is not used in
+ *  any advertising or publicity pertaining to the use or distribution
+ *  of this software without specific, written prior authorization. If
+ *  the above copyright notice or any other identification of the
+ *  University of Michigan is included in any copy of any portion of
+ *  this software, then the disclaimer below must also be included.
+ *
+ *  This software is provided as is, without representation or warranty
+ *  of any kind either express or implied, including without limitation
+ *  the implied warranties of merchantability, fitness for a particular
+ *  purpose, or noninfringement.  The Regents of the University of
+ *  Michigan shall not be liable for any damages, including special,
+ *  indirect, incidental, or consequential damages, with respect to any
+ *  claim arising out of or in connection with the use of the software,
+ *  even if it has been or is hereafter advised of the possibility of
+ *  such damages.
+ */
+
+#include <linux/nfs_fs.h>
+#include <linux/nfs_page.h>
+#include <linux/module.h>
+
+#include <linux/sunrpc/metrics.h>
+
+#include "../nfs4session.h"
+#include "../internal.h"
+#include "../delegation.h"
+#include "filelayout.h"
+#include "../nfs4trace.h"
+
+#define NFSDBG_FACILITY         NFSDBG_PNFS_LD
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Dean Hildebrand <dhildebz@umich.edu>");
+MODULE_DESCRIPTION("The NFSv4 file layout driver");
+
+#define FILELAYOUT_POLL_RETRY_MAX     (15*HZ)
+
+static loff_t
+filelayout_get_dense_offset(struct nfs4_filelayout_segment *flseg,
+                            loff_t offset)
+{
+        u32 stripe_width = flseg->stripe_unit * flseg->dsaddr->stripe_count;
+        u64 stripe_no;
+        u32 rem;
+
+        offset -= flseg->pattern_offset;
+        stripe_no = div_u64(offset, stripe_width);
+        div_u64_rem(offset, flseg->stripe_unit, &rem);
+
+        return stripe_no * flseg->stripe_unit + rem;
+}
+
+/* This function is used by the layout driver to calculate the
+ * offset of the file on the dserver based on whether the
+ * layout type is STRIPE_DENSE or STRIPE_SPARSE
+ */
+static loff_t
+filelayout_get_dserver_offset(struct pnfs_layout_segment *lseg, loff_t offset)
+{
+        struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
+
+        switch (flseg->stripe_type) {
+        case STRIPE_SPARSE:
+                return offset;
+
+        case STRIPE_DENSE:
+                return filelayout_get_dense_offset(flseg, offset);
+        }
+
+        BUG();
+}
+
+static void filelayout_reset_write(struct nfs_pgio_data *data)
+{
+        struct nfs_pgio_header *hdr = data->header;
+        struct rpc_task *task = &data->task;
+
+        if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
+                dprintk("%s Reset task %5u for i/o through MDS "
+                        "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
+                        data->task.tk_pid,
+                        hdr->inode->i_sb->s_id,
+                        (unsigned long long)NFS_FILEID(hdr->inode),
+                        data->args.count,
+                        (unsigned long long)data->args.offset);
+
+                task->tk_status = pnfs_write_done_resend_to_mds(hdr->inode,
+                                                        &hdr->pages,
+                                                        hdr->completion_ops,
+                                                        hdr->dreq);
+        }
+}
+
+static void filelayout_reset_read(struct nfs_pgio_data *data)
+{
+        struct nfs_pgio_header *hdr = data->header;
+        struct rpc_task *task = &data->task;
+
+        if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
+                dprintk("%s Reset task %5u for i/o through MDS "
+                        "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
+                        data->task.tk_pid,
+                        hdr->inode->i_sb->s_id,
+                        (unsigned long long)NFS_FILEID(hdr->inode),
+                        data->args.count,
+                        (unsigned long long)data->args.offset);
+
+                task->tk_status = pnfs_read_done_resend_to_mds(hdr->inode,
+                                                        &hdr->pages,
+                                                        hdr->completion_ops,
+                                                        hdr->dreq);
+        }
+}
+
+static void filelayout_fenceme(struct inode *inode, struct pnfs_layout_hdr *lo)
+{
+        if (!test_and_clear_bit(NFS_LAYOUT_RETURN, &lo->plh_flags))
+                return;
+        pnfs_return_layout(inode);
+}
+
+static int filelayout_async_handle_error(struct rpc_task *task,
+                                         struct nfs4_state *state,
+                                         struct nfs_client *clp,
+                                         struct pnfs_layout_segment *lseg)
+{
+        struct pnfs_layout_hdr *lo = lseg->pls_layout;
+        struct inode *inode = lo->plh_inode;
+        struct nfs_server *mds_server = NFS_SERVER(inode);
+        struct nfs4_deviceid_node *devid = FILELAYOUT_DEVID_NODE(lseg);
+        struct nfs_client *mds_client = mds_server->nfs_client;
+        struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
+
+        if (task->tk_status >= 0)
+                return 0;
+
+        switch (task->tk_status) {
+        /* MDS state errors */
+        case -NFS4ERR_DELEG_REVOKED:
+        case -NFS4ERR_ADMIN_REVOKED:
+        case -NFS4ERR_BAD_STATEID:
+                if (state == NULL)
+                        break;
+                nfs_remove_bad_delegation(state->inode);
+        case -NFS4ERR_OPENMODE:
+                if (state == NULL)
+                        break;
+                if (nfs4_schedule_stateid_recovery(mds_server, state) < 0)
+                        goto out_bad_stateid;
+                goto wait_on_recovery;
+        case -NFS4ERR_EXPIRED:
+                if (state != NULL) {
+                        if (nfs4_schedule_stateid_recovery(mds_server, state) < 0)
+                                goto out_bad_stateid;
+                }
+                nfs4_schedule_lease_recovery(mds_client);
+                goto wait_on_recovery;
+        /* DS session errors */
+        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. Exchangeid "
+                        "flags 0x%x\n", __func__, task->tk_status,
+                        clp->cl_exchange_flags);
+                nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
+                break;
+        case -NFS4ERR_DELAY:
+        case -NFS4ERR_GRACE:
+                rpc_delay(task, FILELAYOUT_POLL_RETRY_MAX);
+                break;
+        case -NFS4ERR_RETRY_UNCACHED_REP:
+                break;
+        /* Invalidate Layout errors */
+        case -NFS4ERR_PNFS_NO_LAYOUT:
+        case -ESTALE:           /* mapped NFS4ERR_STALE */
+        case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
+        case -EISDIR:           /* mapped NFS4ERR_ISDIR */
+        case -NFS4ERR_FHEXPIRED:
+        case -NFS4ERR_WRONG_TYPE:
+                dprintk("%s Invalid layout error %d\n", __func__,
+                        task->tk_status);
+                /*
+                 * Destroy layout so new i/o will get a new layout.
+                 * Layout will not be destroyed until all current lseg
+                 * references are put. Mark layout as invalid to resend failed
+                 * i/o and all i/o waiting on the slot table to the MDS until
+                 * layout is destroyed and a new valid layout is obtained.
+                 */
+                pnfs_destroy_layout(NFS_I(inode));
+                rpc_wake_up(&tbl->slot_tbl_waitq);
+                goto reset;
+        /* RPC connection errors */
+        case -ECONNREFUSED:
+        case -EHOSTDOWN:
+        case -EHOSTUNREACH:
+        case -ENETUNREACH:
+        case -EIO:
+        case -ETIMEDOUT:
+        case -EPIPE:
+                dprintk("%s DS connection error %d\n", __func__,
+                        task->tk_status);
+                nfs4_mark_deviceid_unavailable(devid);
+                set_bit(NFS_LAYOUT_RETURN, &lo->plh_flags);
+                rpc_wake_up(&tbl->slot_tbl_waitq);
+                /* fall through */
+        default:
+reset:
+                dprintk("%s Retry through MDS. Error %d\n", __func__,
+                        task->tk_status);
+                return -NFS4ERR_RESET_TO_MDS;
+        }
+out:
+        task->tk_status = 0;
+        return -EAGAIN;
+out_bad_stateid:
+        task->tk_status = -EIO;
+        return 0;
+wait_on_recovery:
+        rpc_sleep_on(&mds_client->cl_rpcwaitq, task, NULL);
+        if (test_bit(NFS4CLNT_MANAGER_RUNNING, &mds_client->cl_state) == 0)
+                rpc_wake_up_queued_task(&mds_client->cl_rpcwaitq, task);
+        goto out;
+}
+
+/* NFS_PROTO call done callback routines */
+
+static int filelayout_read_done_cb(struct rpc_task *task,
+                                struct nfs_pgio_data *data)
+{
+        struct nfs_pgio_header *hdr = data->header;
+        int err;
+
+        trace_nfs4_pnfs_read(data, task->tk_status);
+        err = filelayout_async_handle_error(task, data->args.context->state,
+                                            data->ds_clp, hdr->lseg);
+
+        switch (err) {
+        case -NFS4ERR_RESET_TO_MDS:
+                filelayout_reset_read(data);
+                return task->tk_status;
+        case -EAGAIN:
+                rpc_restart_call_prepare(task);
+                return -EAGAIN;
+        }
+
+        return 0;
+}
+
+/*
+ * We reference the rpc_cred of the first WRITE that triggers the need for
+ * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
+ * rfc5661 is not clear about which credential should be used.
+ */
+static void
+filelayout_set_layoutcommit(struct nfs_pgio_data *wdata)
+{
+        struct nfs_pgio_header *hdr = wdata->header;
+
+        if (FILELAYOUT_LSEG(hdr->lseg)->commit_through_mds ||
+            wdata->res.verf->committed == NFS_FILE_SYNC)
+                return;
+
+        pnfs_set_layoutcommit(wdata);
+        dprintk("%s ionde %lu pls_end_pos %lu\n", __func__, hdr->inode->i_ino,
+                (unsigned long) NFS_I(hdr->inode)->layout->plh_lwb);
+}
+
+bool
+filelayout_test_devid_unavailable(struct nfs4_deviceid_node *node)
+{
+        return filelayout_test_devid_invalid(node) ||
+                nfs4_test_deviceid_unavailable(node);
+}
+
+static bool
+filelayout_reset_to_mds(struct pnfs_layout_segment *lseg)
+{
+        struct nfs4_deviceid_node *node = FILELAYOUT_DEVID_NODE(lseg);
+
+        return filelayout_test_devid_unavailable(node);
+}
+
+/*
+ * Call ops for the async read/write cases
+ * In the case of dense layouts, the offset needs to be reset to its
+ * original value.
+ */
+static void filelayout_read_prepare(struct rpc_task *task, void *data)
+{
+        struct nfs_pgio_data *rdata = data;
+
+        if (unlikely(test_bit(NFS_CONTEXT_BAD, &rdata->args.context->flags))) {
+                rpc_exit(task, -EIO);
+                return;
+        }
+        if (filelayout_reset_to_mds(rdata->header->lseg)) {
+                dprintk("%s task %u reset io to MDS\n", __func__, task->tk_pid);
+                filelayout_reset_read(rdata);
+                rpc_exit(task, 0);
+                return;
+        }
+        rdata->pgio_done_cb = filelayout_read_done_cb;
+
+        if (nfs41_setup_sequence(rdata->ds_clp->cl_session,
+                        &rdata->args.seq_args,
+                        &rdata->res.seq_res,
+                        task))
+                return;
+        if (nfs4_set_rw_stateid(&rdata->args.stateid, rdata->args.context,
+                        rdata->args.lock_context, FMODE_READ) == -EIO)
+                rpc_exit(task, -EIO); /* lost lock, terminate I/O */
+}
+
+static void filelayout_read_call_done(struct rpc_task *task, void *data)
+{
+        struct nfs_pgio_data *rdata = data;
+
+        dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
+
+        if (test_bit(NFS_IOHDR_REDO, &rdata->header->flags) &&
+            task->tk_status == 0) {
+                nfs41_sequence_done(task, &rdata->res.seq_res);
+                return;
+        }
+
+        /* Note this may cause RPC to be resent */
+        rdata->header->mds_ops->rpc_call_done(task, data);
+}
+
+static void filelayout_read_count_stats(struct rpc_task *task, void *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_pgio_data *rdata = data;
+        struct pnfs_layout_hdr *lo = rdata->header->lseg->pls_layout;
+
+        filelayout_fenceme(lo->plh_inode, lo);
+        nfs_put_client(rdata->ds_clp);
+        rdata->header->mds_ops->rpc_release(data);
+}
+
+static int filelayout_write_done_cb(struct rpc_task *task,
+                                struct nfs_pgio_data *data)
+{
+        struct nfs_pgio_header *hdr = data->header;
+        int err;
+
+        trace_nfs4_pnfs_write(data, task->tk_status);
+        err = filelayout_async_handle_error(task, data->args.context->state,
+                                            data->ds_clp, hdr->lseg);
+
+        switch (err) {
+        case -NFS4ERR_RESET_TO_MDS:
+                filelayout_reset_write(data);
+                return task->tk_status;
+        case -EAGAIN:
+                rpc_restart_call_prepare(task);
+                return -EAGAIN;
+        }
+
+        filelayout_set_layoutcommit(data);
+        return 0;
+}
+
+/* Fake up some data that will cause nfs_commit_release to retry the writes. */
+static void prepare_to_resend_writes(struct nfs_commit_data *data)
+{
+        struct nfs_page *first = nfs_list_entry(data->pages.next);
+
+        data->task.tk_status = 0;
+        memcpy(&data->verf.verifier, &first->wb_verf,
+               sizeof(data->verf.verifier));
+        data->verf.verifier.data[0]++; /* ensure verifier mismatch */
+}
+
+static int filelayout_commit_done_cb(struct rpc_task *task,
+                                     struct nfs_commit_data *data)
+{
+        int err;
+
+        trace_nfs4_pnfs_commit_ds(data, task->tk_status);
+        err = filelayout_async_handle_error(task, NULL, data->ds_clp,
+                                            data->lseg);
+
+        switch (err) {
+        case -NFS4ERR_RESET_TO_MDS:
+                prepare_to_resend_writes(data);
+                return -EAGAIN;
+        case -EAGAIN:
+                rpc_restart_call_prepare(task);
+                return -EAGAIN;
+        }
+
+        return 0;
+}
+
+static void filelayout_write_prepare(struct rpc_task *task, void *data)
+{
+        struct nfs_pgio_data *wdata = data;
+
+        if (unlikely(test_bit(NFS_CONTEXT_BAD, &wdata->args.context->flags))) {
+                rpc_exit(task, -EIO);
+                return;
+        }
+        if (filelayout_reset_to_mds(wdata->header->lseg)) {
+                dprintk("%s task %u reset io to MDS\n", __func__, task->tk_pid);
+                filelayout_reset_write(wdata);
+                rpc_exit(task, 0);
+                return;
+        }
+        if (nfs41_setup_sequence(wdata->ds_clp->cl_session,
+                        &wdata->args.seq_args,
+                        &wdata->res.seq_res,
+                        task))
+                return;
+        if (nfs4_set_rw_stateid(&wdata->args.stateid, wdata->args.context,
+                        wdata->args.lock_context, FMODE_WRITE) == -EIO)
+                rpc_exit(task, -EIO); /* lost lock, terminate I/O */
+}
+
+static void filelayout_write_call_done(struct rpc_task *task, void *data)
+{
+        struct nfs_pgio_data *wdata = data;
+
+        if (test_bit(NFS_IOHDR_REDO, &wdata->header->flags) &&
+            task->tk_status == 0) {
+                nfs41_sequence_done(task, &wdata->res.seq_res);
+                return;
+        }
+
+        /* Note this may cause RPC to be resent */
+        wdata->header->mds_ops->rpc_call_done(task, data);
+}
+
+static void filelayout_write_count_stats(struct rpc_task *task, void *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_pgio_data *wdata = data;
+        struct pnfs_layout_hdr *lo = wdata->header->lseg->pls_layout;
+
+        filelayout_fenceme(lo->plh_inode, lo);
+        nfs_put_client(wdata->ds_clp);
+        wdata->header->mds_ops->rpc_release(data);
+}
+
+static void filelayout_commit_prepare(struct rpc_task *task, void *data)
+{
+        struct nfs_commit_data *wdata = data;
+
+        nfs41_setup_sequence(wdata->ds_clp->cl_session,
+                        &wdata->args.seq_args,
+                        &wdata->res.seq_res,
+                        task);
+}
+
+static void filelayout_write_commit_done(struct rpc_task *task, void *data)
+{
+        struct nfs_commit_data *wdata = data;
+
+        /* Note this may cause RPC to be resent */
+        wdata->mds_ops->rpc_call_done(task, data);
+}
+
+static void filelayout_commit_count_stats(struct rpc_task *task, void *data)
+{
+        struct nfs_commit_data *cdata = data;
+
+        rpc_count_iostats(task, NFS_SERVER(cdata->inode)->client->cl_metrics);
+}
+
+static void filelayout_commit_release(void *calldata)
+{
+        struct nfs_commit_data *data = calldata;
+
+        data->completion_ops->completion(data);
+        pnfs_put_lseg(data->lseg);
+        nfs_put_client(data->ds_clp);
+        nfs_commitdata_release(data);
+}
+
+static const struct rpc_call_ops filelayout_read_call_ops = {
+        .rpc_call_prepare = filelayout_read_prepare,
+        .rpc_call_done = filelayout_read_call_done,
+        .rpc_count_stats = filelayout_read_count_stats,
+        .rpc_release = filelayout_read_release,
+};
+
+static const struct rpc_call_ops filelayout_write_call_ops = {
+        .rpc_call_prepare = filelayout_write_prepare,
+        .rpc_call_done = filelayout_write_call_done,
+        .rpc_count_stats = filelayout_write_count_stats,
+        .rpc_release = filelayout_write_release,
+};
+
+static const struct rpc_call_ops filelayout_commit_call_ops = {
+        .rpc_call_prepare = filelayout_commit_prepare,
+        .rpc_call_done = filelayout_write_commit_done,
+        .rpc_count_stats = filelayout_commit_count_stats,
+        .rpc_release = filelayout_commit_release,
+};
+
+static enum pnfs_try_status
+filelayout_read_pagelist(struct nfs_pgio_data *data)
+{
+        struct nfs_pgio_header *hdr = data->header;
+        struct pnfs_layout_segment *lseg = hdr->lseg;
+        struct nfs4_pnfs_ds *ds;
+        struct rpc_clnt *ds_clnt;
+        loff_t offset = data->args.offset;
+        u32 j, idx;
+        struct nfs_fh *fh;
+
+        dprintk("--> %s ino %lu pgbase %u req %Zu@%llu\n",
+                __func__, hdr->inode->i_ino,
+                data->args.pgbase, (size_t)data->args.count, offset);
+
+        /* Retrieve the correct rpc_client for the byte range */
+        j = nfs4_fl_calc_j_index(lseg, offset);
+        idx = nfs4_fl_calc_ds_index(lseg, j);
+        ds = nfs4_fl_prepare_ds(lseg, idx);
+        if (!ds)
+                return PNFS_NOT_ATTEMPTED;
+
+        ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, hdr->inode);
+        if (IS_ERR(ds_clnt))
+                return PNFS_NOT_ATTEMPTED;
+
+        dprintk("%s USE DS: %s cl_count %d\n", __func__,
+                ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count));
+
+        /* 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;
+
+        data->args.offset = filelayout_get_dserver_offset(lseg, offset);
+        data->mds_offset = offset;
+
+        /* Perform an asynchronous read to ds */
+        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_pgio_data *data, int sync)
+{
+        struct nfs_pgio_header *hdr = data->header;
+        struct pnfs_layout_segment *lseg = hdr->lseg;
+        struct nfs4_pnfs_ds *ds;
+        struct rpc_clnt *ds_clnt;
+        loff_t offset = data->args.offset;
+        u32 j, idx;
+        struct nfs_fh *fh;
+
+        /* Retrieve the correct rpc_client for the byte range */
+        j = nfs4_fl_calc_j_index(lseg, offset);
+        idx = nfs4_fl_calc_ds_index(lseg, j);
+        ds = nfs4_fl_prepare_ds(lseg, idx);
+        if (!ds)
+                return PNFS_NOT_ATTEMPTED;
+
+        ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, hdr->inode);
+        if (IS_ERR(ds_clnt))
+                return PNFS_NOT_ATTEMPTED;
+
+        dprintk("%s ino %lu sync %d req %Zu@%llu DS: %s cl_count %d\n",
+                __func__, hdr->inode->i_ino, sync, (size_t) data->args.count,
+                offset, ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count));
+
+        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_pgio(ds_clnt, data,
+                                    &filelayout_write_call_ops, sync,
+                                    RPC_TASK_SOFTCONN);
+        return PNFS_ATTEMPTED;
+}
+
+/*
+ * filelayout_check_layout()
+ *
+ * Make sure layout segment parameters are sane WRT the device.
+ * At this point no generic layer initialization of the lseg has occurred,
+ * and nothing has been added to the layout_hdr cache.
+ *
+ */
+static int
+filelayout_check_layout(struct pnfs_layout_hdr *lo,
+                        struct nfs4_filelayout_segment *fl,
+                        struct nfs4_layoutget_res *lgr,
+                        struct nfs4_deviceid *id,
+                        gfp_t gfp_flags)
+{
+        struct nfs4_deviceid_node *d;
+        struct nfs4_file_layout_dsaddr *dsaddr;
+        int status = -EINVAL;
+
+        dprintk("--> %s\n", __func__);
+
+        /* FIXME: remove this check when layout segment support is added */
+        if (lgr->range.offset != 0 ||
+            lgr->range.length != NFS4_MAX_UINT64) {
+                dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
+                        __func__);
+                goto out;
+        }
+
+        if (fl->pattern_offset > lgr->range.offset) {
+                dprintk("%s pattern_offset %lld too large\n",
+                                __func__, fl->pattern_offset);
+                goto out;
+        }
+
+        if (!fl->stripe_unit) {
+                dprintk("%s Invalid stripe unit (%u)\n",
+                        __func__, fl->stripe_unit);
+                goto out;
+        }
+
+        /* find and reference the deviceid */
+        d = nfs4_find_get_deviceid(NFS_SERVER(lo->plh_inode)->pnfs_curr_ld,
+                                   NFS_SERVER(lo->plh_inode)->nfs_client, id);
+        if (d == NULL) {
+                dsaddr = filelayout_get_device_info(lo->plh_inode, id,
+                                lo->plh_lc_cred, gfp_flags);
+                if (dsaddr == NULL)
+                        goto out;
+        } else
+                dsaddr = container_of(d, struct nfs4_file_layout_dsaddr, id_node);
+        /* Found deviceid is unavailable */
+        if (filelayout_test_devid_unavailable(&dsaddr->id_node))
+                        goto out_put;
+
+        fl->dsaddr = dsaddr;
+
+        if (fl->first_stripe_index >= dsaddr->stripe_count) {
+                dprintk("%s Bad first_stripe_index %u\n",
+                                __func__, fl->first_stripe_index);
+                goto out_put;
+        }
+
+        if ((fl->stripe_type == STRIPE_SPARSE &&
+            fl->num_fh > 1 && fl->num_fh != dsaddr->ds_num) ||
+            (fl->stripe_type == STRIPE_DENSE &&
+            fl->num_fh != dsaddr->stripe_count)) {
+                dprintk("%s num_fh %u not valid for given packing\n",
+                        __func__, fl->num_fh);
+                goto out_put;
+        }
+
+        status = 0;
+out:
+        dprintk("--> %s returns %d\n", __func__, status);
+        return status;
+out_put:
+        nfs4_fl_put_deviceid(dsaddr);
+        goto out;
+}
+
+static void filelayout_free_fh_array(struct nfs4_filelayout_segment *fl)
+{
+        int i;
+
+        for (i = 0; i < fl->num_fh; i++) {
+                if (!fl->fh_array[i])
+                        break;
+                kfree(fl->fh_array[i]);
+        }
+        kfree(fl->fh_array);
+        fl->fh_array = NULL;
+}
+
+static void
+_filelayout_free_lseg(struct nfs4_filelayout_segment *fl)
+{
+        filelayout_free_fh_array(fl);
+        kfree(fl);
+}
+
+static int
+filelayout_decode_layout(struct pnfs_layout_hdr *flo,
+                         struct nfs4_filelayout_segment *fl,
+                         struct nfs4_layoutget_res *lgr,
+                         struct nfs4_deviceid *id,
+                         gfp_t gfp_flags)
+{
+        struct xdr_stream stream;
+        struct xdr_buf buf;
+        struct page *scratch;
+        __be32 *p;
+        uint32_t nfl_util;
+        int i;
+
+        dprintk("%s: set_layout_map Begin\n", __func__);
+
+        scratch = alloc_page(gfp_flags);
+        if (!scratch)
+                return -ENOMEM;
+
+        xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages, lgr->layoutp->len);
+        xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
+
+        /* 20 = ufl_util (4), first_stripe_index (4), pattern_offset (8),
+         * num_fh (4) */
+        p = xdr_inline_decode(&stream, NFS4_DEVICEID4_SIZE + 20);
+        if (unlikely(!p))
+                goto out_err;
+
+        memcpy(id, p, sizeof(*id));
+        p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
+        nfs4_print_deviceid(id);
+
+        nfl_util = be32_to_cpup(p++);
+        if (nfl_util & NFL4_UFLG_COMMIT_THRU_MDS)
+                fl->commit_through_mds = 1;
+        if (nfl_util & NFL4_UFLG_DENSE)
+                fl->stripe_type = STRIPE_DENSE;
+        else
+                fl->stripe_type = STRIPE_SPARSE;
+        fl->stripe_unit = nfl_util & ~NFL4_UFLG_MASK;
+
+        fl->first_stripe_index = be32_to_cpup(p++);
+        p = xdr_decode_hyper(p, &fl->pattern_offset);
+        fl->num_fh = be32_to_cpup(p++);
+
+        dprintk("%s: nfl_util 0x%X num_fh %u fsi %u po %llu\n",
+                __func__, nfl_util, fl->num_fh, fl->first_stripe_index,
+                fl->pattern_offset);
+
+        /* Note that a zero value for num_fh is legal for STRIPE_SPARSE.
+         * Futher checking is done in filelayout_check_layout */
+        if (fl->num_fh >
+            max(NFS4_PNFS_MAX_STRIPE_CNT, NFS4_PNFS_MAX_MULTI_CNT))
+                goto out_err;
+
+        if (fl->num_fh > 0) {
+                fl->fh_array = kcalloc(fl->num_fh, sizeof(fl->fh_array[0]),
+                                       gfp_flags);
+                if (!fl->fh_array)
+                        goto out_err;
+        }
+
+        for (i = 0; i < fl->num_fh; i++) {
+                /* Do we want to use a mempool here? */
+                fl->fh_array[i] = kmalloc(sizeof(struct nfs_fh), gfp_flags);
+                if (!fl->fh_array[i])
+                        goto out_err_free;
+
+                p = xdr_inline_decode(&stream, 4);
+                if (unlikely(!p))
+                        goto out_err_free;
+                fl->fh_array[i]->size = be32_to_cpup(p++);
+                if (sizeof(struct nfs_fh) < fl->fh_array[i]->size) {
+                        printk(KERN_ERR "NFS: Too big fh %d received %d\n",
+                               i, fl->fh_array[i]->size);
+                        goto out_err_free;
+                }
+
+                p = xdr_inline_decode(&stream, fl->fh_array[i]->size);
+                if (unlikely(!p))
+                        goto out_err_free;
+                memcpy(fl->fh_array[i]->data, p, fl->fh_array[i]->size);
+                dprintk("DEBUG: %s: fh len %d\n", __func__,
+                        fl->fh_array[i]->size);
+        }
+
+        __free_page(scratch);
+        return 0;
+
+out_err_free:
+        filelayout_free_fh_array(fl);
+out_err:
+        __free_page(scratch);
+        return -EIO;
+}
+
+static void
+filelayout_free_lseg(struct pnfs_layout_segment *lseg)
+{
+        struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
+
+        dprintk("--> %s\n", __func__);
+        nfs4_fl_put_deviceid(fl->dsaddr);
+        /* This assumes a single RW lseg */
+        if (lseg->pls_range.iomode == IOMODE_RW) {
+                struct nfs4_filelayout *flo;
+
+                flo = FILELAYOUT_FROM_HDR(lseg->pls_layout);
+                flo->commit_info.nbuckets = 0;
+                kfree(flo->commit_info.buckets);
+                flo->commit_info.buckets = NULL;
+        }
+        _filelayout_free_lseg(fl);
+}
+
+static int
+filelayout_alloc_commit_info(struct pnfs_layout_segment *lseg,
+                             struct nfs_commit_info *cinfo,
+                             gfp_t gfp_flags)
+{
+        struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
+        struct pnfs_commit_bucket *buckets;
+        int size, i;
+
+        if (fl->commit_through_mds)
+                return 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
+                 * associated with a struct list_head, populated by calls
+                 * to filelayout_write_pagelist().
+                 * */
+                return 0;
+        }
+
+        buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
+                          gfp_flags);
+        if (!buckets)
+                return -ENOMEM;
+        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 >= 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 *
+filelayout_alloc_lseg(struct pnfs_layout_hdr *layoutid,
+                      struct nfs4_layoutget_res *lgr,
+                      gfp_t gfp_flags)
+{
+        struct nfs4_filelayout_segment *fl;
+        int rc;
+        struct nfs4_deviceid id;
+
+        dprintk("--> %s\n", __func__);
+        fl = kzalloc(sizeof(*fl), gfp_flags);
+        if (!fl)
+                return NULL;
+
+        rc = filelayout_decode_layout(layoutid, fl, lgr, &id, gfp_flags);
+        if (rc != 0 || filelayout_check_layout(layoutid, fl, lgr, &id, gfp_flags)) {
+                _filelayout_free_lseg(fl);
+                return NULL;
+        }
+        return &fl->generic_hdr;
+}
+
+/*
+ * filelayout_pg_test(). Called by nfs_can_coalesce_requests()
+ *
+ * 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
+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_offset;
+        u64 segment_offset = pgio->pg_lseg->pls_range.offset;
+        u32 stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
+
+        /* calls nfs_generic_pg_test */
+        size = pnfs_generic_pg_test(pgio, prev, req);
+        if (!size)
+                return 0;
+
+        /* 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);
+
+                if (p_stripe != r_stripe)
+                        return 0;
+        }
+
+        /* 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)
+{
+        if (!pgio->pg_lseg)
+                pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
+                                           req->wb_context,
+                                           0,
+                                           NFS4_MAX_UINT64,
+                                           IOMODE_READ,
+                                           GFP_KERNEL);
+        /* If no lseg, fall back to read through mds */
+        if (pgio->pg_lseg == NULL)
+                nfs_pageio_reset_read_mds(pgio);
+}
+
+static void
+filelayout_pg_init_write(struct nfs_pageio_descriptor *pgio,
+                         struct nfs_page *req)
+{
+        struct nfs_commit_info cinfo;
+        int status;
+
+        if (!pgio->pg_lseg)
+                pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
+                                           req->wb_context,
+                                           0,
+                                           NFS4_MAX_UINT64,
+                                           IOMODE_RW,
+                                           GFP_NOFS);
+        /* If no lseg, fall back to write through mds */
+        if (pgio->pg_lseg == NULL)
+                goto out_mds;
+        nfs_init_cinfo(&cinfo, pgio->pg_inode, pgio->pg_dreq);
+        status = filelayout_alloc_commit_info(pgio->pg_lseg, &cinfo, GFP_NOFS);
+        if (status < 0) {
+                pnfs_put_lseg(pgio->pg_lseg);
+                pgio->pg_lseg = NULL;
+                goto out_mds;
+        }
+        return;
+out_mds:
+        nfs_pageio_reset_write_mds(pgio);
+}
+
+static const struct nfs_pageio_ops filelayout_pg_read_ops = {
+        .pg_init = filelayout_pg_init_read,
+        .pg_test = filelayout_pg_test,
+        .pg_doio = pnfs_generic_pg_readpages,
+};
+
+static const struct nfs_pageio_ops filelayout_pg_write_ops = {
+        .pg_init = filelayout_pg_init_write,
+        .pg_test = filelayout_pg_test,
+        .pg_doio = pnfs_generic_pg_writepages,
+};
+
+static u32 select_bucket_index(struct nfs4_filelayout_segment *fl, u32 j)
+{
+        if (fl->stripe_type == STRIPE_SPARSE)
+                return nfs4_fl_calc_ds_index(&fl->generic_hdr, j);
+        else
+                return j;
+}
+
+/* The generic layer is about to remove the req from the commit list.
+ * If this will make the bucket empty, it will need to put the lseg reference.
+ */
+static void
+filelayout_clear_request_commit(struct nfs_page *req,
+                                struct nfs_commit_info *cinfo)
+{
+        struct pnfs_layout_segment *freeme = NULL;
+
+        spin_lock(cinfo->lock);
+        if (!test_and_clear_bit(PG_COMMIT_TO_DS, &req->wb_flags))
+                goto out;
+        cinfo->ds->nwritten--;
+        if (list_is_singular(&req->wb_list)) {
+                struct pnfs_commit_bucket *bucket;
+
+                bucket = list_first_entry(&req->wb_list,
+                                          struct pnfs_commit_bucket,
+                                          written);
+                freeme = bucket->wlseg;
+                bucket->wlseg = NULL;
+        }
+out:
+        nfs_request_remove_commit_list(req, cinfo);
+        spin_unlock(cinfo->lock);
+        pnfs_put_lseg(freeme);
+}
+
+static struct list_head *
+filelayout_choose_commit_list(struct nfs_page *req,
+                              struct pnfs_layout_segment *lseg,
+                              struct nfs_commit_info *cinfo)
+{
+        struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
+        u32 i, j;
+        struct list_head *list;
+        struct pnfs_commit_bucket *buckets;
+
+        if (fl->commit_through_mds)
+                return &cinfo->mds->list;
+
+        /* Note that we are calling nfs4_fl_calc_j_index on each page
+         * that ends up being committed to a data server.  An attractive
+         * alternative is to add a field to nfs_write_data and nfs_page
+         * to store the value calculated in filelayout_write_pagelist
+         * and just use that here.
+         */
+        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)) {
+                /* Non-empty buckets hold a reference on the lseg.  That ref
+                 * is normally transferred to the COMMIT call and released
+                 * there.  It could also be released if the last req is pulled
+                 * off due to a rewrite, in which case it will be done in
+                 * filelayout_clear_request_commit
+                 */
+                buckets[i].wlseg = pnfs_get_lseg(lseg);
+        }
+        set_bit(PG_COMMIT_TO_DS, &req->wb_flags);
+        cinfo->ds->nwritten++;
+        spin_unlock(cinfo->lock);
+        return list;
+}
+
+static void
+filelayout_mark_request_commit(struct nfs_page *req,
+                               struct pnfs_layout_segment *lseg,
+                               struct nfs_commit_info *cinfo)
+{
+        struct list_head *list;
+
+        list = filelayout_choose_commit_list(req, lseg, cinfo);
+        nfs_request_add_commit_list(req, list, cinfo);
+}
+
+static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
+{
+        struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
+
+        if (flseg->stripe_type == STRIPE_SPARSE)
+                return i;
+        else
+                return nfs4_fl_calc_ds_index(lseg, i);
+}
+
+static struct nfs_fh *
+select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
+{
+        struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
+
+        if (flseg->stripe_type == STRIPE_SPARSE) {
+                if (flseg->num_fh == 1)
+                        i = 0;
+                else if (flseg->num_fh == 0)
+                        /* Use the MDS OPEN fh set in nfs_read_rpcsetup */
+                        return NULL;
+        }
+        return flseg->fh_array[i];
+}
+
+static int filelayout_initiate_commit(struct nfs_commit_data *data, int how)
+{
+        struct pnfs_layout_segment *lseg = data->lseg;
+        struct nfs4_pnfs_ds *ds;
+        struct rpc_clnt *ds_clnt;
+        u32 idx;
+        struct nfs_fh *fh;
+
+        idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
+        ds = nfs4_fl_prepare_ds(lseg, idx);
+        if (!ds)
+                goto out_err;
+
+        ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, data->inode);
+        if (IS_ERR(ds_clnt))
+                goto out_err;
+
+        dprintk("%s ino %lu, how %d cl_count %d\n", __func__,
+                data->inode->i_ino, how, atomic_read(&ds->ds_clp->cl_count));
+        data->commit_done_cb = filelayout_commit_done_cb;
+        atomic_inc(&ds->ds_clp->cl_count);
+        data->ds_clp = ds->ds_clp;
+        fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
+        if (fh)
+                data->args.fh = fh;
+        return nfs_initiate_commit(ds_clnt, data,
+                                   &filelayout_commit_call_ops, how,
+                                   RPC_TASK_SOFTCONN);
+out_err:
+        prepare_to_resend_writes(data);
+        filelayout_commit_release(data);
+        return -EAGAIN;
+}
+
+static int
+transfer_commit_list(struct list_head *src, struct list_head *dst,
+                     struct nfs_commit_info *cinfo, int max)
+{
+        struct nfs_page *req, *tmp;
+        int ret = 0;
+
+        list_for_each_entry_safe(req, tmp, src, wb_list) {
+                if (!nfs_lock_request(req))
+                        continue;
+                kref_get(&req->wb_kref);
+                if (cond_resched_lock(cinfo->lock))
+                        list_safe_reset_next(req, tmp, wb_list);
+                nfs_request_remove_commit_list(req, cinfo);
+                clear_bit(PG_COMMIT_TO_DS, &req->wb_flags);
+                nfs_list_add_request(req, dst);
+                ret++;
+                if ((ret == max) && !cinfo->dreq)
+                        break;
+        }
+        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,
+                               int max)
+{
+        struct list_head *src = &bucket->written;
+        struct list_head *dst = &bucket->committing;
+        int ret;
+
+        ret = transfer_commit_list(src, dst, cinfo, max);
+        if (ret) {
+                cinfo->ds->nwritten -= ret;
+                cinfo->ds->ncommitting += ret;
+                bucket->clseg = bucket->wlseg;
+                if (list_empty(src))
+                        bucket->wlseg = NULL;
+                else
+                        pnfs_get_lseg(bucket->clseg);
+        }
+        return ret;
+}
+
+/* Move reqs from written to committing lists, returning count of number moved.
+ * Note called with cinfo->lock held.
+ */
+static int filelayout_scan_commit_lists(struct nfs_commit_info *cinfo,
+                                        int max)
+{
+        int i, rv = 0, cnt;
+
+        for (i = 0; i < cinfo->ds->nbuckets && max != 0; i++) {
+                cnt = filelayout_scan_ds_commit_list(&cinfo->ds->buckets[i],
+                                                     cinfo, max);
+                max -= cnt;
+                rv += cnt;
+        }
+        return rv;
+}
+
+/* Pull everything off the committing lists and dump into @dst */
+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;
+        int i;
+
+restart:
+        spin_lock(cinfo->lock);
+        for (i = 0, b = cinfo->ds->buckets; i < cinfo->ds->nbuckets; i++, b++) {
+                if (transfer_commit_list(&b->written, dst, cinfo, 0)) {
+                        freeme = b->wlseg;
+                        b->wlseg = NULL;
+                        spin_unlock(cinfo->lock);
+                        pnfs_put_lseg(freeme);
+                        goto restart;
+                }
+        }
+        cinfo->ds->nwritten = 0;
+        spin_unlock(cinfo->lock);
+}
+
+static unsigned int
+alloc_ds_commits(struct nfs_commit_info *cinfo, struct list_head *list)
+{
+        struct pnfs_ds_commit_info *fl_cinfo;
+        struct pnfs_commit_bucket *bucket;
+        struct nfs_commit_data *data;
+        int i, j;
+        unsigned int nreq = 0;
+        struct pnfs_layout_segment *freeme;
+
+        fl_cinfo = cinfo->ds;
+        bucket = fl_cinfo->buckets;
+        for (i = 0; i < fl_cinfo->nbuckets; i++, bucket++) {
+                if (list_empty(&bucket->committing))
+                        continue;
+                data = nfs_commitdata_alloc();
+                if (!data)
+                        break;
+                data->ds_commit_index = i;
+                spin_lock(cinfo->lock);
+                data->lseg = bucket->clseg;
+                bucket->clseg = NULL;
+                spin_unlock(cinfo->lock);
+                list_add(&data->pages, list);
+                nreq++;
+        }
+
+        /* Clean up on error */
+        for (j = i; j < fl_cinfo->nbuckets; j++, bucket++) {
+                if (list_empty(&bucket->committing))
+                        continue;
+                nfs_retry_commit(&bucket->committing, bucket->clseg, cinfo);
+                spin_lock(cinfo->lock);
+                freeme = bucket->clseg;
+                bucket->clseg = NULL;
+                spin_unlock(cinfo->lock);
+                pnfs_put_lseg(freeme);
+        }
+        /* Caller will clean up entries put on list */
+        return nreq;
+}
+
+/* This follows nfs_commit_list pretty closely */
+static int
+filelayout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
+                           int how, struct nfs_commit_info *cinfo)
+{
+        struct nfs_commit_data *data, *tmp;
+        LIST_HEAD(list);
+        unsigned int nreq = 0;
+
+        if (!list_empty(mds_pages)) {
+                data = nfs_commitdata_alloc();
+                if (data != NULL) {
+                        data->lseg = NULL;
+                        list_add(&data->pages, &list);
+                        nreq++;
+                } else
+                        nfs_retry_commit(mds_pages, NULL, cinfo);
+        }
+
+        nreq += alloc_ds_commits(cinfo, &list);
+
+        if (nreq == 0) {
+                cinfo->completion_ops->error_cleanup(NFS_I(inode));
+                goto out;
+        }
+
+        atomic_add(nreq, &cinfo->mds->rpcs_out);
+
+        list_for_each_entry_safe(data, tmp, &list, pages) {
+                list_del_init(&data->pages);
+                if (!data->lseg) {
+                        nfs_init_commit(data, mds_pages, NULL, cinfo);
+                        nfs_initiate_commit(NFS_CLIENT(inode), data,
+                                            data->mds_ops, how, 0);
+                } else {
+                        struct pnfs_commit_bucket *buckets;
+
+                        buckets = cinfo->ds->buckets;
+                        nfs_init_commit(data, &buckets[data->ds_commit_index].committing, data->lseg, cinfo);
+                        filelayout_initiate_commit(data, how);
+                }
+        }
+out:
+        cinfo->ds->ncommitting = 0;
+        return PNFS_ATTEMPTED;
+}
+
+static void
+filelayout_free_deveiceid_node(struct nfs4_deviceid_node *d)
+{
+        nfs4_fl_free_deviceid(container_of(d, struct nfs4_file_layout_dsaddr, id_node));
+}
+
+static struct pnfs_layout_hdr *
+filelayout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
+{
+        struct nfs4_filelayout *flo;
+
+        flo = kzalloc(sizeof(*flo), gfp_flags);
+        return flo != NULL ? &flo->generic_hdr : NULL;
+}
+
+static void
+filelayout_free_layout_hdr(struct pnfs_layout_hdr *lo)
+{
+        kfree(FILELAYOUT_FROM_HDR(lo));
+}
+
+static struct pnfs_ds_commit_info *
+filelayout_get_ds_info(struct inode *inode)
+{
+        struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
+
+        if (layout == NULL)
+                return NULL;
+        else
+                return &FILELAYOUT_FROM_HDR(layout)->commit_info;
+}
+
+static struct pnfs_layoutdriver_type filelayout_type = {
+        .id                     = LAYOUT_NFSV4_1_FILES,
+        .name                   = "LAYOUT_NFSV4_1_FILES",
+        .owner                  = THIS_MODULE,
+        .alloc_layout_hdr       = filelayout_alloc_layout_hdr,
+        .free_layout_hdr        = filelayout_free_layout_hdr,
+        .alloc_lseg             = filelayout_alloc_lseg,
+        .free_lseg              = filelayout_free_lseg,
+        .pg_read_ops            = &filelayout_pg_read_ops,
+        .pg_write_ops           = &filelayout_pg_write_ops,
+        .get_ds_info            = &filelayout_get_ds_info,
+        .mark_request_commit    = filelayout_mark_request_commit,
+        .clear_request_commit   = filelayout_clear_request_commit,
+        .scan_commit_lists      = filelayout_scan_commit_lists,
+        .recover_commit_reqs    = filelayout_recover_commit_reqs,
+        .commit_pagelist        = filelayout_commit_pagelist,
+        .read_pagelist          = filelayout_read_pagelist,
+        .write_pagelist         = filelayout_write_pagelist,
+        .free_deviceid_node     = filelayout_free_deveiceid_node,
+};
+
+static int __init nfs4filelayout_init(void)
+{
+        printk(KERN_INFO "%s: NFSv4 File Layout Driver Registering...\n",
+               __func__);
+        return pnfs_register_layoutdriver(&filelayout_type);
+}
+
+static void __exit nfs4filelayout_exit(void)
+{
+        printk(KERN_INFO "%s: NFSv4 File Layout Driver Unregistering...\n",
+               __func__);
+        pnfs_unregister_layoutdriver(&filelayout_type);
+}
+
+MODULE_ALIAS("nfs-layouttype4-1");
+
+module_init(nfs4filelayout_init);
+module_exit(nfs4filelayout_exit);