summaryrefslogtreecommitdiffstats
path: root/fs/nfs/nfs4filelayout.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/nfs/nfs4filelayout.c')
-rw-r--r--fs/nfs/nfs4filelayout.c892
1 files changed, 892 insertions, 0 deletions
diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
new file mode 100644
index 00000000000..be79dc9f386
--- /dev/null
+++ b/fs/nfs/nfs4filelayout.c
@@ -0,0 +1,892 @@
+/*
+ * 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 "internal.h"
+#include "nfs4filelayout.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 tmp;
+
+ offset -= flseg->pattern_offset;
+ tmp = offset;
+ do_div(tmp, stripe_width);
+
+ return tmp * flseg->stripe_unit + do_div(offset, flseg->stripe_unit);
+}
+
+/* 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();
+}
+
+/* For data server errors we don't recover from */
+static void
+filelayout_set_lo_fail(struct pnfs_layout_segment *lseg)
+{
+ if (lseg->pls_range.iomode == IOMODE_RW) {
+ dprintk("%s Setting layout IOMODE_RW fail bit\n", __func__);
+ set_bit(lo_fail_bit(IOMODE_RW), &lseg->pls_layout->plh_flags);
+ } else {
+ dprintk("%s Setting layout IOMODE_READ fail bit\n", __func__);
+ set_bit(lo_fail_bit(IOMODE_READ), &lseg->pls_layout->plh_flags);
+ }
+}
+
+static int filelayout_async_handle_error(struct rpc_task *task,
+ struct nfs4_state *state,
+ struct nfs_client *clp,
+ int *reset)
+{
+ if (task->tk_status >= 0)
+ return 0;
+
+ *reset = 0;
+
+ switch (task->tk_status) {
+ 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);
+ break;
+ case -NFS4ERR_DELAY:
+ case -NFS4ERR_GRACE:
+ case -EKEYEXPIRED:
+ rpc_delay(task, FILELAYOUT_POLL_RETRY_MAX);
+ break;
+ case -NFS4ERR_RETRY_UNCACHED_REP:
+ break;
+ default:
+ dprintk("%s DS error. Retry through MDS %d\n", __func__,
+ task->tk_status);
+ *reset = 1;
+ break;
+ }
+ task->tk_status = 0;
+ return -EAGAIN;
+}
+
+/* NFS_PROTO call done callback routines */
+
+static int filelayout_read_done_cb(struct rpc_task *task,
+ struct nfs_read_data *data)
+{
+ struct nfs_client *clp = data->ds_clp;
+ int reset = 0;
+
+ dprintk("%s DS read\n", __func__);
+
+ if (filelayout_async_handle_error(task, data->args.context->state,
+ data->ds_clp, &reset) == -EAGAIN) {
+ dprintk("%s calling restart ds_clp %p ds_clp->cl_session %p\n",
+ __func__, data->ds_clp, data->ds_clp->cl_session);
+ if (reset) {
+ filelayout_set_lo_fail(data->lseg);
+ nfs4_reset_read(task, data);
+ clp = NFS_SERVER(data->inode)->nfs_client;
+ }
+ nfs_restart_rpc(task, clp);
+ 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_write_data *wdata)
+{
+ if (FILELAYOUT_LSEG(wdata->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__, wdata->inode->i_ino,
+ (unsigned long) wdata->lseg->pls_end_pos);
+}
+
+/*
+ * 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_read_data *rdata = (struct nfs_read_data *)data;
+
+ rdata->read_done_cb = filelayout_read_done_cb;
+
+ if (nfs41_setup_sequence(rdata->ds_clp->cl_session,
+ &rdata->args.seq_args, &rdata->res.seq_res,
+ 0, task))
+ return;
+
+ rpc_call_start(task);
+}
+
+static void filelayout_read_call_done(struct rpc_task *task, void *data)
+{
+ struct nfs_read_data *rdata = (struct nfs_read_data *)data;
+
+ dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
+
+ /* Note this may cause RPC to be resent */
+ rdata->mds_ops->rpc_call_done(task, data);
+}
+
+static void filelayout_read_release(void *data)
+{
+ struct nfs_read_data *rdata = (struct nfs_read_data *)data;
+
+ rdata->mds_ops->rpc_release(data);
+}
+
+static int filelayout_write_done_cb(struct rpc_task *task,
+ struct nfs_write_data *data)
+{
+ int reset = 0;
+
+ if (filelayout_async_handle_error(task, data->args.context->state,
+ data->ds_clp, &reset) == -EAGAIN) {
+ struct nfs_client *clp;
+
+ dprintk("%s calling restart ds_clp %p ds_clp->cl_session %p\n",
+ __func__, data->ds_clp, data->ds_clp->cl_session);
+ if (reset) {
+ filelayout_set_lo_fail(data->lseg);
+ nfs4_reset_write(task, data);
+ clp = NFS_SERVER(data->inode)->nfs_client;
+ } else
+ clp = data->ds_clp;
+ nfs_restart_rpc(task, clp);
+ 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_write_data *data)
+{
+ struct nfs_page *first = nfs_list_entry(data->pages.next);
+
+ data->task.tk_status = 0;
+ memcpy(data->verf.verifier, first->wb_verf.verifier,
+ sizeof(first->wb_verf.verifier));
+ data->verf.verifier[0]++; /* ensure verifier mismatch */
+}
+
+static int filelayout_commit_done_cb(struct rpc_task *task,
+ struct nfs_write_data *data)
+{
+ int reset = 0;
+
+ if (filelayout_async_handle_error(task, data->args.context->state,
+ data->ds_clp, &reset) == -EAGAIN) {
+ dprintk("%s calling restart ds_clp %p ds_clp->cl_session %p\n",
+ __func__, data->ds_clp, data->ds_clp->cl_session);
+ if (reset) {
+ prepare_to_resend_writes(data);
+ filelayout_set_lo_fail(data->lseg);
+ } else
+ nfs_restart_rpc(task, data->ds_clp);
+ return -EAGAIN;
+ }
+
+ return 0;
+}
+
+static void filelayout_write_prepare(struct rpc_task *task, void *data)
+{
+ struct nfs_write_data *wdata = (struct nfs_write_data *)data;
+
+ if (nfs41_setup_sequence(wdata->ds_clp->cl_session,
+ &wdata->args.seq_args, &wdata->res.seq_res,
+ 0, task))
+ return;
+
+ rpc_call_start(task);
+}
+
+static void filelayout_write_call_done(struct rpc_task *task, void *data)
+{
+ struct nfs_write_data *wdata = (struct nfs_write_data *)data;
+
+ /* Note this may cause RPC to be resent */
+ wdata->mds_ops->rpc_call_done(task, data);
+}
+
+static void filelayout_write_release(void *data)
+{
+ struct nfs_write_data *wdata = (struct nfs_write_data *)data;
+
+ wdata->mds_ops->rpc_release(data);
+}
+
+static void filelayout_commit_release(void *data)
+{
+ struct nfs_write_data *wdata = (struct nfs_write_data *)data;
+
+ nfs_commit_release_pages(wdata);
+ if (atomic_dec_and_test(&NFS_I(wdata->inode)->commits_outstanding))
+ nfs_commit_clear_lock(NFS_I(wdata->inode));
+ nfs_commitdata_release(wdata);
+}
+
+struct rpc_call_ops filelayout_read_call_ops = {
+ .rpc_call_prepare = filelayout_read_prepare,
+ .rpc_call_done = filelayout_read_call_done,
+ .rpc_release = filelayout_read_release,
+};
+
+struct rpc_call_ops filelayout_write_call_ops = {
+ .rpc_call_prepare = filelayout_write_prepare,
+ .rpc_call_done = filelayout_write_call_done,
+ .rpc_release = filelayout_write_release,
+};
+
+struct rpc_call_ops filelayout_commit_call_ops = {
+ .rpc_call_prepare = filelayout_write_prepare,
+ .rpc_call_done = filelayout_write_call_done,
+ .rpc_release = filelayout_commit_release,
+};
+
+static enum pnfs_try_status
+filelayout_read_pagelist(struct nfs_read_data *data)
+{
+ struct pnfs_layout_segment *lseg = data->lseg;
+ struct nfs4_pnfs_ds *ds;
+ loff_t offset = data->args.offset;
+ u32 j, idx;
+ struct nfs_fh *fh;
+ int status;
+
+ dprintk("--> %s ino %lu pgbase %u req %Zu@%llu\n",
+ __func__, data->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) {
+ /* Either layout fh index faulty, or ds connect failed */
+ set_bit(lo_fail_bit(IOMODE_RW), &lseg->pls_layout->plh_flags);
+ set_bit(lo_fail_bit(IOMODE_READ), &lseg->pls_layout->plh_flags);
+ return PNFS_NOT_ATTEMPTED;
+ }
+ dprintk("%s USE DS:ip %x %hu\n", __func__,
+ ntohl(ds->ds_ip_addr), ntohs(ds->ds_port));
+
+ /* No multipath support. Use first DS */
+ data->ds_clp = ds->ds_clp;
+ 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 */
+ status = nfs_initiate_read(data, ds->ds_clp->cl_rpcclient,
+ &filelayout_read_call_ops);
+ BUG_ON(status != 0);
+ return PNFS_ATTEMPTED;
+}
+
+/* Perform async writes. */
+static enum pnfs_try_status
+filelayout_write_pagelist(struct nfs_write_data *data, int sync)
+{
+ struct pnfs_layout_segment *lseg = data->lseg;
+ struct nfs4_pnfs_ds *ds;
+ loff_t offset = data->args.offset;
+ u32 j, idx;
+ struct nfs_fh *fh;
+ int status;
+
+ /* 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) {
+ printk(KERN_ERR "%s: prepare_ds failed, use MDS\n", __func__);
+ set_bit(lo_fail_bit(IOMODE_RW), &lseg->pls_layout->plh_flags);
+ set_bit(lo_fail_bit(IOMODE_READ), &lseg->pls_layout->plh_flags);
+ return PNFS_NOT_ATTEMPTED;
+ }
+ dprintk("%s ino %lu sync %d req %Zu@%llu DS:%x:%hu\n", __func__,
+ data->inode->i_ino, sync, (size_t) data->args.count, offset,
+ ntohl(ds->ds_ip_addr), ntohs(ds->ds_port));
+
+ data->write_done_cb = filelayout_write_done_cb;
+ data->ds_clp = ds->ds_clp;
+ 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);
+ data->mds_offset = offset;
+
+ /* Perform an asynchronous write */
+ status = nfs_initiate_write(data, ds->ds_clp->cl_rpcclient,
+ &filelayout_write_call_ops, sync);
+ BUG_ON(status != 0);
+ 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_file_layout_dsaddr *dsaddr;
+ int status = -EINVAL;
+ struct nfs_server *nfss = NFS_SERVER(lo->plh_inode);
+
+ dprintk("--> %s\n", __func__);
+
+ if (fl->pattern_offset > lgr->range.offset) {
+ dprintk("%s pattern_offset %lld to large\n",
+ __func__, fl->pattern_offset);
+ goto out;
+ }
+
+ if (!fl->stripe_unit || fl->stripe_unit % PAGE_SIZE) {
+ dprintk("%s Invalid stripe unit (%u)\n",
+ __func__, fl->stripe_unit);
+ goto out;
+ }
+
+ /* find and reference the deviceid */
+ dsaddr = nfs4_fl_find_get_deviceid(id);
+ if (dsaddr == NULL) {
+ dsaddr = get_device_info(lo->plh_inode, id, gfp_flags);
+ if (dsaddr == NULL)
+ goto out;
+ }
+ fl->dsaddr = dsaddr;
+
+ if (fl->first_stripe_index < 0 ||
+ fl->first_stripe_index >= dsaddr->stripe_count) {
+ dprintk("%s Bad first_stripe_index %d\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;
+ }
+
+ 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);
+ 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 = {
+ .pages = lgr->layoutp->pages,
+ .page_len = lgr->layoutp->len,
+ .buflen = lgr->layoutp->len,
+ .len = lgr->layoutp->len,
+ };
+ 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(&stream, &buf, NULL);
+ 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);
+ 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);
+
+ if (!fl->num_fh)
+ goto out_err;
+
+ fl->fh_array = kzalloc(fl->num_fh * sizeof(struct nfs_fh *),
+ 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 "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);
+ kfree(fl->commit_buckets);
+ _filelayout_free_lseg(fl);
+}
+
+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;
+ }
+
+ /* 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().
+ * */
+ if ((!fl->commit_through_mds) && (lgr->range.iomode == IOMODE_RW)) {
+ int i;
+ int size = (fl->stripe_type == STRIPE_SPARSE) ?
+ fl->dsaddr->ds_num : fl->dsaddr->stripe_count;
+
+ fl->commit_buckets = kcalloc(size, sizeof(struct list_head), gfp_flags);
+ if (!fl->commit_buckets) {
+ filelayout_free_lseg(&fl->generic_hdr);
+ return NULL;
+ }
+ fl->number_of_buckets = size;
+ for (i = 0; i < size; i++)
+ INIT_LIST_HEAD(&fl->commit_buckets[i]);
+ }
+ return &fl->generic_hdr;
+}
+
+/*
+ * filelayout_pg_test(). Called by nfs_can_coalesce_requests()
+ *
+ * return 1 : coalesce page
+ * return 0 : don't coalesce page
+ */
+int
+filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
+ struct nfs_page *req)
+{
+ u64 p_stripe, r_stripe;
+ u32 stripe_unit;
+
+ if (!pgio->pg_lseg)
+ return 1;
+ p_stripe = (u64)prev->wb_index << PAGE_CACHE_SHIFT;
+ r_stripe = (u64)req->wb_index << PAGE_CACHE_SHIFT;
+ stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
+
+ do_div(p_stripe, stripe_unit);
+ do_div(r_stripe, stripe_unit);
+
+ return (p_stripe == r_stripe);
+}
+
+static bool filelayout_mark_pnfs_commit(struct pnfs_layout_segment *lseg)
+{
+ return !FILELAYOUT_LSEG(lseg)->commit_through_mds;
+}
+
+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;
+}
+
+struct list_head *filelayout_choose_commit_list(struct nfs_page *req)
+{
+ struct pnfs_layout_segment *lseg = req->wb_commit_lseg;
+ struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
+ u32 i, j;
+ struct list_head *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,
+ (loff_t)req->wb_index << PAGE_CACHE_SHIFT);
+ i = select_bucket_index(fl, j);
+ list = &fl->commit_buckets[i];
+ if (list_empty(list)) {
+ /* Non-empty buckets hold a reference on the lseg */
+ get_lseg(lseg);
+ }
+ return list;
+}
+
+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_write_data *data, int how)
+{
+ struct pnfs_layout_segment *lseg = data->lseg;
+ struct nfs4_pnfs_ds *ds;
+ 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) {
+ printk(KERN_ERR "%s: prepare_ds failed, use MDS\n", __func__);
+ set_bit(lo_fail_bit(IOMODE_RW), &lseg->pls_layout->plh_flags);
+ set_bit(lo_fail_bit(IOMODE_READ), &lseg->pls_layout->plh_flags);
+ prepare_to_resend_writes(data);
+ data->mds_ops->rpc_release(data);
+ return -EAGAIN;
+ }
+ dprintk("%s ino %lu, how %d\n", __func__, data->inode->i_ino, how);
+ data->write_done_cb = filelayout_commit_done_cb;
+ 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(data, ds->ds_clp->cl_rpcclient,
+ &filelayout_commit_call_ops, how);
+}
+
+/*
+ * This is only useful while we are using whole file layouts.
+ */
+static struct pnfs_layout_segment *find_only_write_lseg(struct inode *inode)
+{
+ struct pnfs_layout_segment *lseg, *rv = NULL;
+
+ spin_lock(&inode->i_lock);
+ list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list)
+ if (lseg->pls_range.iomode == IOMODE_RW)
+ rv = get_lseg(lseg);
+ spin_unlock(&inode->i_lock);
+ return rv;
+}
+
+static int alloc_ds_commits(struct inode *inode, struct list_head *list)
+{
+ struct pnfs_layout_segment *lseg;
+ struct nfs4_filelayout_segment *fl;
+ struct nfs_write_data *data;
+ int i, j;
+
+ /* Won't need this when non-whole file layout segments are supported
+ * instead we will use a pnfs_layout_hdr structure */
+ lseg = find_only_write_lseg(inode);
+ if (!lseg)
+ return 0;
+ fl = FILELAYOUT_LSEG(lseg);
+ for (i = 0; i < fl->number_of_buckets; i++) {
+ if (list_empty(&fl->commit_buckets[i]))
+ continue;
+ data = nfs_commitdata_alloc();
+ if (!data)
+ goto out_bad;
+ data->ds_commit_index = i;
+ data->lseg = lseg;
+ list_add(&data->pages, list);
+ }
+ put_lseg(lseg);
+ return 0;
+
+out_bad:
+ for (j = i; j < fl->number_of_buckets; j++) {
+ if (list_empty(&fl->commit_buckets[i]))
+ continue;
+ nfs_retry_commit(&fl->commit_buckets[i], lseg);
+ put_lseg(lseg); /* associated with emptying bucket */
+ }
+ put_lseg(lseg);
+ /* Caller will clean up entries put on list */
+ return -ENOMEM;
+}
+
+/* This follows nfs_commit_list pretty closely */
+static int
+filelayout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
+ int how)
+{
+ struct nfs_write_data *data, *tmp;
+ LIST_HEAD(list);
+
+ if (!list_empty(mds_pages)) {
+ data = nfs_commitdata_alloc();
+ if (!data)
+ goto out_bad;
+ data->lseg = NULL;
+ list_add(&data->pages, &list);
+ }
+
+ if (alloc_ds_commits(inode, &list))
+ goto out_bad;
+
+ list_for_each_entry_safe(data, tmp, &list, pages) {
+ list_del_init(&data->pages);
+ atomic_inc(&NFS_I(inode)->commits_outstanding);
+ if (!data->lseg) {
+ nfs_init_commit(data, mds_pages, NULL);
+ nfs_initiate_commit(data, NFS_CLIENT(inode),
+ data->mds_ops, how);
+ } else {
+ nfs_init_commit(data, &FILELAYOUT_LSEG(data->lseg)->commit_buckets[data->ds_commit_index], data->lseg);
+ filelayout_initiate_commit(data, how);
+ }
+ }
+ return 0;
+ out_bad:
+ list_for_each_entry_safe(data, tmp, &list, pages) {
+ nfs_retry_commit(&data->pages, data->lseg);
+ list_del_init(&data->pages);
+ nfs_commit_free(data);
+ }
+ nfs_retry_commit(mds_pages, NULL);
+ nfs_commit_clear_lock(NFS_I(inode));
+ return -ENOMEM;
+}
+
+static struct pnfs_layoutdriver_type filelayout_type = {
+ .id = LAYOUT_NFSV4_1_FILES,
+ .name = "LAYOUT_NFSV4_1_FILES",
+ .owner = THIS_MODULE,
+ .alloc_lseg = filelayout_alloc_lseg,
+ .free_lseg = filelayout_free_lseg,
+ .pg_test = filelayout_pg_test,
+ .mark_pnfs_commit = filelayout_mark_pnfs_commit,
+ .choose_commit_list = filelayout_choose_commit_list,
+ .commit_pagelist = filelayout_commit_pagelist,
+ .read_pagelist = filelayout_read_pagelist,
+ .write_pagelist = filelayout_write_pagelist,
+};
+
+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_init(nfs4filelayout_init);
+module_exit(nfs4filelayout_exit);