blob: e5f841cb6227f543149341d3722afc0647775a0c [file] [log] [blame]
/*
* 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 "internal.h"
#include "pnfs.h"
static void pnfs_generic_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);
}
void pnfs_generic_rw_release(void *data)
{
struct nfs_pgio_header *hdr = data;
struct pnfs_layout_hdr *lo = hdr->lseg->pls_layout;
pnfs_generic_fenceme(lo->plh_inode, lo);
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 is must be called holding the inode (/cinfo) 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->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
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;
ret = pnfs_generic_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.
*/
int pnfs_generic_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 = pnfs_generic_scan_ds_commit_list(&cinfo->ds->buckets[i],
cinfo, max);
max -= cnt;
rv += cnt;
}
return rv;
}
EXPORT_SYMBOL_GPL(pnfs_generic_scan_commit_lists);
/* Pull everything off the committing lists and dump into @dst */
void pnfs_generic_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 (pnfs_generic_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);
}
EXPORT_SYMBOL_GPL(pnfs_generic_recover_commit_reqs);
static void pnfs_generic_retry_commit(struct nfs_commit_info *cinfo, int idx)
{
struct pnfs_ds_commit_info *fl_cinfo = cinfo->ds;
struct pnfs_commit_bucket *bucket;
struct pnfs_layout_segment *freeme;
int i;
for (i = idx; i < fl_cinfo->nbuckets; i++) {
bucket = &fl_cinfo->buckets[i];
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);
}
}
static unsigned int
pnfs_generic_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;
unsigned int nreq = 0;
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 */
pnfs_generic_retry_commit(cinfo, i);
return nreq;
}
/* This follows nfs_commit_list pretty closely */
int
pnfs_generic_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
int how, struct nfs_commit_info *cinfo,
int (*initiate_commit)(struct nfs_commit_data *data,
int how))
{
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);
pnfs_generic_retry_commit(cinfo, 0);
cinfo->completion_ops->error_cleanup(NFS_I(inode));
return -ENOMEM;
}
}
nreq += pnfs_generic_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);
initiate_commit(data, how);
}
}
out:
cinfo->ds->ncommitting = 0;
return PNFS_ATTEMPTED;
}
EXPORT_SYMBOL_GPL(pnfs_generic_commit_pagelist);