/*
* Common NFS I/O operations for the pnfs file based
* layout drivers.
*
* Copyright (c) 2014, Primary Data, Inc. All rights reserved.
*
* Tom Haynes <loghyr@primarydata.com>
*/
#include <linux/nfs_fs.h>
#include <linux/nfs_page.h>
#include <linux/sunrpc/addr.h>
#include <linux/module.h>
#include "nfs4session.h"
#include "internal.h"
#include "pnfs.h"
#define NFSDBG_FACILITY NFSDBG_PNFS
void pnfs_generic_rw_release(void *data)
{
struct nfs_pgio_header *hdr = data;
nfs_put_client(hdr->ds_clp);
hdr->mds_ops->rpc_release(data);
}
EXPORT_SYMBOL_GPL(pnfs_generic_rw_release);
/* Fake up some data that will cause nfs_commit_release to retry the writes. */
void pnfs_generic_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 */
}
EXPORT_SYMBOL_GPL(pnfs_generic_prepare_to_resend_writes);
void pnfs_generic_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);
}
EXPORT_SYMBOL_GPL(pnfs_generic_write_commit_done);
void pnfs_generic_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);
}
EXPORT_SYMBOL_GPL(pnfs_generic_commit_release);
/* 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.
* Note this must be called holding i_lock
*/
void
pnfs_generic_clear_request_commit(struct nfs_page *req,
struct nfs_commit_info *cinfo)
{
struct pnfs_layout_segment *freeme = NULL;
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);
pnfs_put_lseg_locked(freeme);
}
EXPORT_SYMBOL_GPL(pnfs_generic_clear_request_commit);
static int
pnfs_generic_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->inode->i_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;
}
static int
pnfs_generic_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;
lockdep_assert_held(&cinfo->inode->i_lock);
ret = pnfs_generic_transfer_commit_list(src, dst, cinfo, max);
if (ret) {
cinfo->ds->nwritten -= ret;
cinfo->ds->ncommitting += ret;
if (bucket->clseg == NULL)
bucket->clseg = pnfs_get_lseg(bucket->wlseg);
if (list_empty(src)) {
pnfs_put_lseg_locked(bucket->wlseg);
bucket->wlseg = NULL;
}
}
return ret;
}
/* Move reqs from written to committing lists, returning count
* of number moved.
*/
int pnfs_generic_scan_commit_lists(struct nfs_commit_info *cinfo,
int max)
{
int i, rv = 0, cnt;
lockdep_assert_held(&cinfo->inode->i_lock);
for (i = 0; i < cinfo->ds->nbuckets &&