#include <linux/file.h>
#include <linux/writeback.h>
#include <linux/swap.h>
+#include <linux/migrate.h>
#include <linux/sunrpc/clnt.h>
#include <linux/nfs_fs.h>
#include "delegation.h"
#include "internal.h"
#include "iostat.h"
+#include "nfs4_fs.h"
+#include "fscache.h"
#define NFSDBG_FACILITY NFSDBG_PAGECACHE
return p;
}
-static void nfs_writedata_free(struct nfs_write_data *p)
+void nfs_writedata_free(struct nfs_write_data *p)
{
if (p && (p->pagevec != &p->page_array[0]))
kfree(p->pagevec);
mempool_free(p, nfs_wdata_mempool);
}
-void nfs_writedata_release(void *data)
+static void nfs_writedata_release(struct nfs_write_data *wdata)
{
- struct nfs_write_data *wdata = data;
-
put_nfs_open_context(wdata->args.context);
nfs_writedata_free(wdata);
}
{
if (wbc->for_reclaim)
return FLUSH_HIGHPRI | FLUSH_STABLE;
- if (wbc->for_kupdate)
+ if (wbc->for_kupdate || wbc->for_background)
return FLUSH_LOWPRI;
return 0;
}
struct inode *inode = page->mapping->host;
struct nfs_server *nfss = NFS_SERVER(inode);
+ page_cache_get(page);
if (atomic_long_inc_return(&nfss->writeback) >
- NFS_CONGESTION_ON_THRESH)
- set_bdi_congested(&nfss->backing_dev_info, WRITE);
+ NFS_CONGESTION_ON_THRESH) {
+ set_bdi_congested(&nfss->backing_dev_info,
+ BLK_RW_ASYNC);
+ }
}
return ret;
}
struct nfs_server *nfss = NFS_SERVER(inode);
end_page_writeback(page);
+ page_cache_release(page);
if (atomic_long_dec_return(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH)
- clear_bdi_congested(&nfss->backing_dev_info, WRITE);
+ clear_bdi_congested(&nfss->backing_dev_info, BLK_RW_ASYNC);
}
-/*
- * Find an associated nfs write request, and prepare to flush it out
- * May return an error if the user signalled nfs_wait_on_request().
- */
-static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
- struct page *page)
+static struct nfs_page *nfs_find_and_lock_request(struct page *page)
{
struct inode *inode = page->mapping->host;
struct nfs_page *req;
int ret;
spin_lock(&inode->i_lock);
- for(;;) {
+ for (;;) {
req = nfs_page_find_request_locked(page);
- if (req == NULL) {
- spin_unlock(&inode->i_lock);
- return 0;
- }
+ if (req == NULL)
+ break;
if (nfs_set_page_tag_locked(req))
break;
/* Note: If we hold the page lock, as is the case in nfs_writepage,
ret = nfs_wait_on_request(req);
nfs_release_request(req);
if (ret != 0)
- return ret;
+ return ERR_PTR(ret);
spin_lock(&inode->i_lock);
}
- if (test_bit(PG_CLEAN, &req->wb_flags)) {
- spin_unlock(&inode->i_lock);
- BUG();
- }
- if (nfs_set_page_writeback(page) != 0) {
- spin_unlock(&inode->i_lock);
- BUG();
- }
spin_unlock(&inode->i_lock);
+ return req;
+}
+
+/*
+ * Find an associated nfs write request, and prepare to flush it out
+ * May return an error if the user signalled nfs_wait_on_request().
+ */
+static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
+ struct page *page)
+{
+ struct nfs_page *req;
+ int ret = 0;
+
+ req = nfs_find_and_lock_request(page);
+ if (!req)
+ goto out;
+ ret = PTR_ERR(req);
+ if (IS_ERR(req))
+ goto out;
+
+ ret = nfs_set_page_writeback(page);
+ BUG_ON(ret != 0);
+ BUG_ON(test_bit(PG_CLEAN, &req->wb_flags));
+
if (!nfs_pageio_add_request(pgio, req)) {
nfs_redirty_request(req);
- return pgio->pg_error;
+ ret = pgio->pg_error;
}
- return 0;
+out:
+ return ret;
}
static int nfs_do_writepage(struct page *page, struct writeback_control *wbc, struct nfs_pageio_descriptor *pgio)
nfs_mark_request_dirty(struct nfs_page *req)
{
__set_page_dirty_nobuffers(req->wb_page);
+ __mark_inode_dirty(req->wb_page->mapping->host, I_DIRTY_DATASYNC);
}
#if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
radix_tree_tag_set(&nfsi->nfs_page_tree,
req->wb_index,
NFS_PAGE_TAG_COMMIT);
+ nfsi->ncommit++;
spin_unlock(&inode->i_lock);
inc_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
inc_bdi_stat(req->wb_page->mapping->backing_dev_info, BDI_RECLAIMABLE);
}
#endif
-/*
- * Wait for a request to complete.
- *
- * Interruptible by fatal signals only.
- */
-static int nfs_wait_on_requests_locked(struct inode *inode, pgoff_t idx_start, unsigned int npages)
-{
- struct nfs_inode *nfsi = NFS_I(inode);
- struct nfs_page *req;
- pgoff_t idx_end, next;
- unsigned int res = 0;
- int error;
-
- if (npages == 0)
- idx_end = ~0;
- else
- idx_end = idx_start + npages - 1;
-
- next = idx_start;
- while (radix_tree_gang_lookup_tag(&nfsi->nfs_page_tree, (void **)&req, next, 1, NFS_PAGE_TAG_LOCKED)) {
- if (req->wb_index > idx_end)
- break;
-
- next = req->wb_index + 1;
- BUG_ON(!NFS_WBACK_BUSY(req));
-
- kref_get(&req->wb_kref);
- spin_unlock(&inode->i_lock);
- error = nfs_wait_on_request(req);
- nfs_release_request(req);
- spin_lock(&inode->i_lock);
- if (error < 0)
- return error;
- res++;
- }
- return res;
-}
-
-static void nfs_cancel_commit_list(struct list_head *head)
-{
- struct nfs_page *req;
-
- while(!list_empty(head)) {
- req = nfs_list_entry(head->next);
- nfs_list_remove_request(req);
- nfs_clear_request_commit(req);
- nfs_inode_remove_request(req);
- nfs_unlock_request(req);
- }
-}
-
#if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
static int
nfs_need_commit(struct nfs_inode *nfsi)
nfs_scan_commit(struct inode *inode, struct list_head *dst, pgoff_t idx_start, unsigned int npages)
{
struct nfs_inode *nfsi = NFS_I(inode);
+ int ret;
if (!nfs_need_commit(nfsi))
return 0;
- return nfs_scan_list(nfsi, dst, idx_start, npages, NFS_PAGE_TAG_COMMIT);
+ ret = nfs_scan_list(nfsi, dst, idx_start, npages, NFS_PAGE_TAG_COMMIT);
+ if (ret > 0)
+ nfsi->ncommit -= ret;
+ if (nfs_need_commit(NFS_I(inode)))
+ __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
+ return ret;
}
#else
static inline int nfs_need_commit(struct nfs_inode *nfsi)
spin_lock(&inode->i_lock);
}
- if (nfs_clear_request_commit(req))
- radix_tree_tag_clear(&NFS_I(inode)->nfs_page_tree,
- req->wb_index, NFS_PAGE_TAG_COMMIT);
+ if (nfs_clear_request_commit(req) &&
+ radix_tree_tag_clear(&NFS_I(inode)->nfs_page_tree,
+ req->wb_index, NFS_PAGE_TAG_COMMIT) != NULL)
+ NFS_I(inode)->ncommit--;
/* Okay, the request matches. Update the region */
if (offset < req->wb_offset) {
req = nfs_setup_write_request(ctx, page, offset, count);
if (IS_ERR(req))
return PTR_ERR(req);
+ nfs_mark_request_dirty(req);
/* Update file length */
nfs_grow_file(page, offset, count);
nfs_mark_uptodate(page, req->wb_pgbase, req->wb_bytes);
+ nfs_mark_request_dirty(req);
nfs_clear_page_tag_locked(req);
return 0;
}
*/
if (nfs_write_pageuptodate(page, inode) &&
inode->i_flock == NULL &&
- !(file->f_flags & O_SYNC)) {
+ !(file->f_flags & O_DSYNC)) {
count = max(count + offset, nfs_page_length(page));
offset = 0;
}
status = nfs_writepage_setup(ctx, page, offset, count);
if (status < 0)
nfs_set_pageerror(page);
- else
- __set_page_dirty_nobuffers(page);
dprintk("NFS: nfs_updatepage returns %d (isize %lld)\n",
status, (long long)i_size_read(inode));
static void nfs_writepage_release(struct nfs_page *req)
{
+ struct page *page = req->wb_page;
- if (PageError(req->wb_page) || !nfs_reschedule_unstable_write(req)) {
- nfs_end_page_writeback(req->wb_page);
+ if (PageError(req->wb_page) || !nfs_reschedule_unstable_write(req))
nfs_inode_remove_request(req);
- } else
- nfs_end_page_writeback(req->wb_page);
nfs_clear_page_tag_locked(req);
+ nfs_end_page_writeback(page);
}
static int flush_task_priority(int how)
int how)
{
struct inode *inode = req->wb_context->path.dentry->d_inode;
- int flags = (how & FLUSH_SYNC) ? 0 : RPC_TASK_ASYNC;
int priority = flush_task_priority(how);
struct rpc_task *task;
struct rpc_message msg = {
.callback_ops = call_ops,
.callback_data = data,
.workqueue = nfsiod_workqueue,
- .flags = flags,
+ .flags = RPC_TASK_ASYNC,
.priority = priority,
};
+ int ret = 0;
/* Set up the RPC argument and reply structs
* NB: take care not to mess about with data->commit et al. */
(unsigned long long)data->args.offset);
task = rpc_run_task(&task_setup_data);
- if (IS_ERR(task))
- return PTR_ERR(task);
+ if (IS_ERR(task)) {
+ ret = PTR_ERR(task);
+ goto out;
+ }
+ if (how & FLUSH_SYNC) {
+ ret = rpc_wait_for_completion_task(task);
+ if (ret == 0)
+ ret = task->tk_status;
+ }
rpc_put_task(task);
- return 0;
+out:
+ return ret;
}
/* If a nfs_flush_* function fails, it should remove reqs from @head and
*/
static void nfs_redirty_request(struct nfs_page *req)
{
+ struct page *page = req->wb_page;
+
nfs_mark_request_dirty(req);
- nfs_end_page_writeback(req->wb_page);
nfs_clear_page_tag_locked(req);
+ nfs_end_page_writeback(page);
}
/*
nfs_writedata_release(calldata);
}
+#if defined(CONFIG_NFS_V4_1)
+void nfs_write_prepare(struct rpc_task *task, void *calldata)
+{
+ struct nfs_write_data *data = calldata;
+ struct nfs_client *clp = (NFS_SERVER(data->inode))->nfs_client;
+
+ if (nfs4_setup_sequence(clp, &data->args.seq_args,
+ &data->res.seq_res, 1, task))
+ return;
+ rpc_call_start(task);
+}
+#endif /* CONFIG_NFS_V4_1 */
+
static const struct rpc_call_ops nfs_write_partial_ops = {
+#if defined(CONFIG_NFS_V4_1)
+ .rpc_call_prepare = nfs_write_prepare,
+#endif /* CONFIG_NFS_V4_1 */
.rpc_call_done = nfs_writeback_done_partial,
.rpc_release = nfs_writeback_release_partial,
};
if (nfs_write_need_commit(data)) {
memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf));
nfs_mark_request_commit(req);
- nfs_end_page_writeback(page);
dprintk(" marked for commit\n");
goto next;
}
dprintk(" OK\n");
remove_request:
- nfs_end_page_writeback(page);
nfs_inode_remove_request(req);
next:
nfs_clear_page_tag_locked(req);
+ nfs_end_page_writeback(page);
}
nfs_writedata_release(calldata);
}
static const struct rpc_call_ops nfs_write_full_ops = {
+#if defined(CONFIG_NFS_V4_1)
+ .rpc_call_prepare = nfs_write_prepare,
+#endif /* CONFIG_NFS_V4_1 */
.rpc_call_done = nfs_writeback_done_full,
.rpc_release = nfs_writeback_release_full,
};
{
struct nfs_writeargs *argp = &data->args;
struct nfs_writeres *resp = &data->res;
+ struct nfs_server *server = NFS_SERVER(data->inode);
int status;
dprintk("NFS: %5u nfs_writeback_done (status %d)\n",
if (time_before(complain, jiffies)) {
dprintk("NFS: faulty NFS server %s:"
" (committed = %d) != (stable = %d)\n",
- NFS_SERVER(data->inode)->nfs_client->cl_hostname,
+ server->nfs_client->cl_hostname,
resp->verf->committed, argp->stable);
complain = jiffies + 300 * HZ;
}
*/
argp->stable = NFS_FILE_SYNC;
}
- rpc_restart_call(task);
+ nfs_restart_rpc(task, server->nfs_client);
return -EAGAIN;
}
if (time_before(complain, jiffies)) {
#if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
-void nfs_commitdata_release(void *data)
+static int nfs_commit_set_lock(struct nfs_inode *nfsi, int may_wait)
+{
+ if (!test_and_set_bit(NFS_INO_COMMIT, &nfsi->flags))
+ return 1;
+ if (may_wait && !out_of_line_wait_on_bit_lock(&nfsi->flags,
+ NFS_INO_COMMIT, nfs_wait_bit_killable,
+ TASK_KILLABLE))
+ return 1;
+ return 0;
+}
+
+static void nfs_commit_clear_lock(struct nfs_inode *nfsi)
+{
+ clear_bit(NFS_INO_COMMIT, &nfsi->flags);
+ smp_mb__after_clear_bit();
+ wake_up_bit(&nfsi->flags, NFS_INO_COMMIT);
+}
+
+
+static void nfs_commitdata_release(void *data)
{
struct nfs_write_data *wdata = data;
{
struct nfs_page *first = nfs_list_entry(head->next);
struct inode *inode = first->wb_context->path.dentry->d_inode;
- int flags = (how & FLUSH_SYNC) ? 0 : RPC_TASK_ASYNC;
int priority = flush_task_priority(how);
struct rpc_task *task;
struct rpc_message msg = {
.callback_ops = &nfs_commit_ops,
.callback_data = data,
.workqueue = nfsiod_workqueue,
- .flags = flags,
+ .flags = RPC_TASK_ASYNC,
.priority = priority,
};
BDI_RECLAIMABLE);
nfs_clear_page_tag_locked(req);
}
+ nfs_commit_clear_lock(NFS_I(inode));
return -ENOMEM;
}
next:
nfs_clear_page_tag_locked(req);
}
+ nfs_commit_clear_lock(NFS_I(data->inode));
nfs_commitdata_release(calldata);
}
static const struct rpc_call_ops nfs_commit_ops = {
+#if defined(CONFIG_NFS_V4_1)
+ .rpc_call_prepare = nfs_write_prepare,
+#endif /* CONFIG_NFS_V4_1 */
.rpc_call_done = nfs_commit_done,
.rpc_release = nfs_commit_release,
};
-int nfs_commit_inode(struct inode *inode, int how)
+static int nfs_commit_inode(struct inode *inode, int how)
{
LIST_HEAD(head);
- int res;
+ int may_wait = how & FLUSH_SYNC;
+ int res = 0;
+ if (!nfs_commit_set_lock(NFS_I(inode), may_wait))
+ goto out;
spin_lock(&inode->i_lock);
res = nfs_scan_commit(inode, &head, 0, 0);
spin_unlock(&inode->i_lock);
int error = nfs_commit_list(inode, &head, how);
if (error < 0)
return error;
- }
+ if (may_wait)
+ wait_on_bit(&NFS_I(inode)->flags, NFS_INO_COMMIT,
+ nfs_wait_bit_killable,
+ TASK_KILLABLE);
+ } else
+ nfs_commit_clear_lock(NFS_I(inode));
+out:
return res;
}
-#else
-static inline int nfs_commit_list(struct inode *inode, struct list_head *head, int how)
-{
- return 0;
-}
-#endif
-long nfs_sync_mapping_wait(struct address_space *mapping, struct writeback_control *wbc, int how)
+static int nfs_commit_unstable_pages(struct inode *inode, struct writeback_control *wbc)
{
- struct inode *inode = mapping->host;
- pgoff_t idx_start, idx_end;
- unsigned int npages = 0;
- LIST_HEAD(head);
- int nocommit = how & FLUSH_NOCOMMIT;
- long pages, ret;
-
- /* FIXME */
- if (wbc->range_cyclic)
- idx_start = 0;
- else {
- idx_start = wbc->range_start >> PAGE_CACHE_SHIFT;
- idx_end = wbc->range_end >> PAGE_CACHE_SHIFT;
- if (idx_end > idx_start) {
- pgoff_t l_npages = 1 + idx_end - idx_start;
- npages = l_npages;
- if (sizeof(npages) != sizeof(l_npages) &&
- (pgoff_t)npages != l_npages)
- npages = 0;
+ struct nfs_inode *nfsi = NFS_I(inode);
+ int flags = FLUSH_SYNC;
+ int ret = 0;
+
+ /* Don't commit yet if this is a non-blocking flush and there are
+ * lots of outstanding writes for this mapping.
+ */
+ if (wbc->sync_mode == WB_SYNC_NONE &&
+ nfsi->ncommit <= (nfsi->npages >> 1))
+ goto out_mark_dirty;
+
+ if (wbc->nonblocking || wbc->for_background)
+ flags = 0;
+ ret = nfs_commit_inode(inode, flags);
+ if (ret >= 0) {
+ if (wbc->sync_mode == WB_SYNC_NONE) {
+ if (ret < wbc->nr_to_write)
+ wbc->nr_to_write -= ret;
+ else
+ wbc->nr_to_write = 0;
}
+ return 0;
}
- how &= ~FLUSH_NOCOMMIT;
- spin_lock(&inode->i_lock);
- do {
- ret = nfs_wait_on_requests_locked(inode, idx_start, npages);
- if (ret != 0)
- continue;
- if (nocommit)
- break;
- pages = nfs_scan_commit(inode, &head, idx_start, npages);
- if (pages == 0)
- break;
- if (how & FLUSH_INVALIDATE) {
- spin_unlock(&inode->i_lock);
- nfs_cancel_commit_list(&head);
- ret = pages;
- spin_lock(&inode->i_lock);
- continue;
- }
- pages += nfs_scan_commit(inode, &head, 0, 0);
- spin_unlock(&inode->i_lock);
- ret = nfs_commit_list(inode, &head, how);
- spin_lock(&inode->i_lock);
-
- } while (ret >= 0);
- spin_unlock(&inode->i_lock);
+out_mark_dirty:
+ __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
return ret;
}
-
-static int __nfs_write_mapping(struct address_space *mapping, struct writeback_control *wbc, int how)
+#else
+static int nfs_commit_inode(struct inode *inode, int how)
{
- int ret;
-
- ret = nfs_writepages(mapping, wbc);
- if (ret < 0)
- goto out;
- ret = nfs_sync_mapping_wait(mapping, wbc, how);
- if (ret < 0)
- goto out;
return 0;
-out:
- __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
- return ret;
}
-/* Two pass sync: first using WB_SYNC_NONE, then WB_SYNC_ALL */
-static int nfs_write_mapping(struct address_space *mapping, int how)
+static int nfs_commit_unstable_pages(struct inode *inode, struct writeback_control *wbc)
{
- struct writeback_control wbc = {
- .bdi = mapping->backing_dev_info,
- .sync_mode = WB_SYNC_ALL,
- .nr_to_write = LONG_MAX,
- .range_start = 0,
- .range_end = LLONG_MAX,
- .for_writepages = 1,
- };
+ return 0;
+}
+#endif
- return __nfs_write_mapping(mapping, &wbc, how);
+int nfs_write_inode(struct inode *inode, struct writeback_control *wbc)
+{
+ return nfs_commit_unstable_pages(inode, wbc);
}
/*
*/
int nfs_wb_all(struct inode *inode)
{
- return nfs_write_mapping(inode->i_mapping, 0);
-}
+ struct writeback_control wbc = {
+ .sync_mode = WB_SYNC_ALL,
+ .nr_to_write = LONG_MAX,
+ .range_start = 0,
+ .range_end = LLONG_MAX,
+ };
-int nfs_wb_nocommit(struct inode *inode)
-{
- return nfs_write_mapping(inode->i_mapping, FLUSH_NOCOMMIT);
+ return sync_inode(inode, &wbc);
}
int nfs_wb_page_cancel(struct inode *inode, struct page *page)
{
struct nfs_page *req;
- loff_t range_start = page_offset(page);
- loff_t range_end = range_start + (loff_t)(PAGE_CACHE_SIZE - 1);
- struct writeback_control wbc = {
- .bdi = page->mapping->backing_dev_info,
- .sync_mode = WB_SYNC_ALL,
- .nr_to_write = LONG_MAX,
- .range_start = range_start,
- .range_end = range_end,
- };
int ret = 0;
BUG_ON(!PageLocked(page));
for (;;) {
+ wait_on_page_writeback(page);
req = nfs_page_find_request(page);
if (req == NULL)
- goto out;
- if (test_bit(PG_CLEAN, &req->wb_flags)) {
- nfs_release_request(req);
break;
- }
if (nfs_lock_request_dontget(req)) {
nfs_inode_remove_request(req);
/*
break;
}
ret = nfs_wait_on_request(req);
+ nfs_release_request(req);
if (ret < 0)
- goto out;
+ break;
}
- if (!PagePrivate(page))
- return 0;
- ret = nfs_sync_mapping_wait(page->mapping, &wbc, FLUSH_INVALIDATE);
-out:
return ret;
}
-static int nfs_wb_page_priority(struct inode *inode, struct page *page,
- int how)
+/*
+ * Write back all requests on one page - we do this before reading it.
+ */
+int nfs_wb_page(struct inode *inode, struct page *page)
{
loff_t range_start = page_offset(page);
loff_t range_end = range_start + (loff_t)(PAGE_CACHE_SIZE - 1);
struct writeback_control wbc = {
- .bdi = page->mapping->backing_dev_info,
.sync_mode = WB_SYNC_ALL,
- .nr_to_write = LONG_MAX,
+ .nr_to_write = 0,
.range_start = range_start,
.range_end = range_end,
};
int ret;
- do {
+ while(PagePrivate(page)) {
+ wait_on_page_writeback(page);
if (clear_page_dirty_for_io(page)) {
ret = nfs_writepage_locked(page, &wbc);
if (ret < 0)
goto out_error;
- } else if (!PagePrivate(page))
- break;
- ret = nfs_sync_mapping_wait(page->mapping, &wbc, how);
+ }
+ ret = sync_inode(inode, &wbc);
if (ret < 0)
goto out_error;
- } while (PagePrivate(page));
+ }
return 0;
out_error:
- __mark_inode_dirty(inode, I_DIRTY_PAGES);
return ret;
}
-/*
- * Write back all requests on one page - we do this before reading it.
- */
-int nfs_wb_page(struct inode *inode, struct page* page)
+#ifdef CONFIG_MIGRATION
+int nfs_migrate_page(struct address_space *mapping, struct page *newpage,
+ struct page *page)
{
- return nfs_wb_page_priority(inode, page, FLUSH_STABLE);
+ struct nfs_page *req;
+ int ret;
+
+ nfs_fscache_release_page(page, GFP_KERNEL);
+
+ req = nfs_find_and_lock_request(page);
+ ret = PTR_ERR(req);
+ if (IS_ERR(req))
+ goto out;
+
+ ret = migrate_page(mapping, newpage, page);
+ if (!req)
+ goto out;
+ if (ret)
+ goto out_unlock;
+ page_cache_get(newpage);
+ spin_lock(&mapping->host->i_lock);
+ req->wb_page = newpage;
+ SetPagePrivate(newpage);
+ set_page_private(newpage, (unsigned long)req);
+ ClearPagePrivate(page);
+ set_page_private(page, 0);
+ spin_unlock(&mapping->host->i_lock);
+ page_cache_release(page);
+out_unlock:
+ nfs_clear_page_tag_locked(req);
+out:
+ return ret;
}
+#endif
int __init nfs_init_writepagecache(void)
{