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- /* handling of writes to regular files and writing back to the server
- *
- * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
- #include <linux/backing-dev.h>
- #include <linux/slab.h>
- #include <linux/fs.h>
- #include <linux/pagemap.h>
- #include <linux/writeback.h>
- #include <linux/pagevec.h>
- #include "internal.h"
- /*
- * mark a page as having been made dirty and thus needing writeback
- */
- int afs_set_page_dirty(struct page *page)
- {
- _enter("");
- return __set_page_dirty_nobuffers(page);
- }
- /*
- * partly or wholly fill a page that's under preparation for writing
- */
- static int afs_fill_page(struct afs_vnode *vnode, struct key *key,
- loff_t pos, unsigned int len, struct page *page)
- {
- struct afs_read *req;
- int ret;
- _enter(",,%llu", (unsigned long long)pos);
- req = kzalloc(sizeof(struct afs_read) + sizeof(struct page *),
- GFP_KERNEL);
- if (!req)
- return -ENOMEM;
- refcount_set(&req->usage, 1);
- req->pos = pos;
- req->len = len;
- req->nr_pages = 1;
- req->pages = req->array;
- req->pages[0] = page;
- get_page(page);
- ret = afs_fetch_data(vnode, key, req);
- afs_put_read(req);
- if (ret < 0) {
- if (ret == -ENOENT) {
- _debug("got NOENT from server"
- " - marking file deleted and stale");
- set_bit(AFS_VNODE_DELETED, &vnode->flags);
- ret = -ESTALE;
- }
- }
- _leave(" = %d", ret);
- return ret;
- }
- /*
- * prepare to perform part of a write to a page
- */
- int afs_write_begin(struct file *file, struct address_space *mapping,
- loff_t pos, unsigned len, unsigned flags,
- struct page **pagep, void **fsdata)
- {
- struct afs_vnode *vnode = AFS_FS_I(file_inode(file));
- struct page *page;
- struct key *key = afs_file_key(file);
- unsigned long priv;
- unsigned f, from = pos & (PAGE_SIZE - 1);
- unsigned t, to = from + len;
- pgoff_t index = pos >> PAGE_SHIFT;
- int ret;
- _enter("{%x:%u},{%lx},%u,%u",
- vnode->fid.vid, vnode->fid.vnode, index, from, to);
- /* We want to store information about how much of a page is altered in
- * page->private.
- */
- BUILD_BUG_ON(PAGE_SIZE > 32768 && sizeof(page->private) < 8);
- page = grab_cache_page_write_begin(mapping, index, flags);
- if (!page)
- return -ENOMEM;
- if (!PageUptodate(page) && len != PAGE_SIZE) {
- ret = afs_fill_page(vnode, key, pos & PAGE_MASK, PAGE_SIZE, page);
- if (ret < 0) {
- unlock_page(page);
- put_page(page);
- _leave(" = %d [prep]", ret);
- return ret;
- }
- SetPageUptodate(page);
- }
- /* page won't leak in error case: it eventually gets cleaned off LRU */
- *pagep = page;
- try_again:
- /* See if this page is already partially written in a way that we can
- * merge the new write with.
- */
- t = f = 0;
- if (PagePrivate(page)) {
- priv = page_private(page);
- f = priv & AFS_PRIV_MAX;
- t = priv >> AFS_PRIV_SHIFT;
- ASSERTCMP(f, <=, t);
- }
- if (f != t) {
- if (PageWriteback(page)) {
- trace_afs_page_dirty(vnode, tracepoint_string("alrdy"),
- page->index, priv);
- goto flush_conflicting_write;
- }
- /* If the file is being filled locally, allow inter-write
- * spaces to be merged into writes. If it's not, only write
- * back what the user gives us.
- */
- if (!test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags) &&
- (to < f || from > t))
- goto flush_conflicting_write;
- if (from < f)
- f = from;
- if (to > t)
- t = to;
- } else {
- f = from;
- t = to;
- }
- priv = (unsigned long)t << AFS_PRIV_SHIFT;
- priv |= f;
- trace_afs_page_dirty(vnode, tracepoint_string("begin"),
- page->index, priv);
- SetPagePrivate(page);
- set_page_private(page, priv);
- _leave(" = 0");
- return 0;
- /* The previous write and this write aren't adjacent or overlapping, so
- * flush the page out.
- */
- flush_conflicting_write:
- _debug("flush conflict");
- ret = write_one_page(page);
- if (ret < 0) {
- _leave(" = %d", ret);
- return ret;
- }
- ret = lock_page_killable(page);
- if (ret < 0) {
- _leave(" = %d", ret);
- return ret;
- }
- goto try_again;
- }
- /*
- * finalise part of a write to a page
- */
- int afs_write_end(struct file *file, struct address_space *mapping,
- loff_t pos, unsigned len, unsigned copied,
- struct page *page, void *fsdata)
- {
- struct afs_vnode *vnode = AFS_FS_I(file_inode(file));
- struct key *key = afs_file_key(file);
- loff_t i_size, maybe_i_size;
- int ret;
- _enter("{%x:%u},{%lx}",
- vnode->fid.vid, vnode->fid.vnode, page->index);
- maybe_i_size = pos + copied;
- i_size = i_size_read(&vnode->vfs_inode);
- if (maybe_i_size > i_size) {
- spin_lock(&vnode->wb_lock);
- i_size = i_size_read(&vnode->vfs_inode);
- if (maybe_i_size > i_size)
- i_size_write(&vnode->vfs_inode, maybe_i_size);
- spin_unlock(&vnode->wb_lock);
- }
- if (!PageUptodate(page)) {
- if (copied < len) {
- /* Try and load any missing data from the server. The
- * unmarshalling routine will take care of clearing any
- * bits that are beyond the EOF.
- */
- ret = afs_fill_page(vnode, key, pos + copied,
- len - copied, page);
- if (ret < 0)
- goto out;
- }
- SetPageUptodate(page);
- }
- set_page_dirty(page);
- if (PageDirty(page))
- _debug("dirtied");
- ret = copied;
- out:
- unlock_page(page);
- put_page(page);
- return ret;
- }
- /*
- * kill all the pages in the given range
- */
- static void afs_kill_pages(struct address_space *mapping,
- pgoff_t first, pgoff_t last)
- {
- struct afs_vnode *vnode = AFS_FS_I(mapping->host);
- struct pagevec pv;
- unsigned count, loop;
- _enter("{%x:%u},%lx-%lx",
- vnode->fid.vid, vnode->fid.vnode, first, last);
- pagevec_init(&pv);
- do {
- _debug("kill %lx-%lx", first, last);
- count = last - first + 1;
- if (count > PAGEVEC_SIZE)
- count = PAGEVEC_SIZE;
- pv.nr = find_get_pages_contig(mapping, first, count, pv.pages);
- ASSERTCMP(pv.nr, ==, count);
- for (loop = 0; loop < count; loop++) {
- struct page *page = pv.pages[loop];
- ClearPageUptodate(page);
- SetPageError(page);
- end_page_writeback(page);
- if (page->index >= first)
- first = page->index + 1;
- lock_page(page);
- generic_error_remove_page(mapping, page);
- unlock_page(page);
- }
- __pagevec_release(&pv);
- } while (first <= last);
- _leave("");
- }
- /*
- * Redirty all the pages in a given range.
- */
- static void afs_redirty_pages(struct writeback_control *wbc,
- struct address_space *mapping,
- pgoff_t first, pgoff_t last)
- {
- struct afs_vnode *vnode = AFS_FS_I(mapping->host);
- struct pagevec pv;
- unsigned count, loop;
- _enter("{%x:%u},%lx-%lx",
- vnode->fid.vid, vnode->fid.vnode, first, last);
- pagevec_init(&pv);
- do {
- _debug("redirty %lx-%lx", first, last);
- count = last - first + 1;
- if (count > PAGEVEC_SIZE)
- count = PAGEVEC_SIZE;
- pv.nr = find_get_pages_contig(mapping, first, count, pv.pages);
- ASSERTCMP(pv.nr, ==, count);
- for (loop = 0; loop < count; loop++) {
- struct page *page = pv.pages[loop];
- redirty_page_for_writepage(wbc, page);
- end_page_writeback(page);
- if (page->index >= first)
- first = page->index + 1;
- }
- __pagevec_release(&pv);
- } while (first <= last);
- _leave("");
- }
- /*
- * write to a file
- */
- static int afs_store_data(struct address_space *mapping,
- pgoff_t first, pgoff_t last,
- unsigned offset, unsigned to)
- {
- struct afs_vnode *vnode = AFS_FS_I(mapping->host);
- struct afs_fs_cursor fc;
- struct afs_wb_key *wbk = NULL;
- struct list_head *p;
- int ret = -ENOKEY, ret2;
- _enter("%s{%x:%u.%u},%lx,%lx,%x,%x",
- vnode->volume->name,
- vnode->fid.vid,
- vnode->fid.vnode,
- vnode->fid.unique,
- first, last, offset, to);
- spin_lock(&vnode->wb_lock);
- p = vnode->wb_keys.next;
- /* Iterate through the list looking for a valid key to use. */
- try_next_key:
- while (p != &vnode->wb_keys) {
- wbk = list_entry(p, struct afs_wb_key, vnode_link);
- _debug("wbk %u", key_serial(wbk->key));
- ret2 = key_validate(wbk->key);
- if (ret2 == 0)
- goto found_key;
- if (ret == -ENOKEY)
- ret = ret2;
- p = p->next;
- }
- spin_unlock(&vnode->wb_lock);
- afs_put_wb_key(wbk);
- _leave(" = %d [no keys]", ret);
- return ret;
- found_key:
- refcount_inc(&wbk->usage);
- spin_unlock(&vnode->wb_lock);
- _debug("USE WB KEY %u", key_serial(wbk->key));
- ret = -ERESTARTSYS;
- if (afs_begin_vnode_operation(&fc, vnode, wbk->key)) {
- while (afs_select_fileserver(&fc)) {
- fc.cb_break = afs_calc_vnode_cb_break(vnode);
- afs_fs_store_data(&fc, mapping, first, last, offset, to);
- }
- afs_check_for_remote_deletion(&fc, fc.vnode);
- afs_vnode_commit_status(&fc, vnode, fc.cb_break);
- ret = afs_end_vnode_operation(&fc);
- }
- switch (ret) {
- case 0:
- afs_stat_v(vnode, n_stores);
- atomic_long_add((last * PAGE_SIZE + to) -
- (first * PAGE_SIZE + offset),
- &afs_v2net(vnode)->n_store_bytes);
- break;
- case -EACCES:
- case -EPERM:
- case -ENOKEY:
- case -EKEYEXPIRED:
- case -EKEYREJECTED:
- case -EKEYREVOKED:
- _debug("next");
- spin_lock(&vnode->wb_lock);
- p = wbk->vnode_link.next;
- afs_put_wb_key(wbk);
- goto try_next_key;
- }
- afs_put_wb_key(wbk);
- _leave(" = %d", ret);
- return ret;
- }
- /*
- * Synchronously write back the locked page and any subsequent non-locked dirty
- * pages.
- */
- static int afs_write_back_from_locked_page(struct address_space *mapping,
- struct writeback_control *wbc,
- struct page *primary_page,
- pgoff_t final_page)
- {
- struct afs_vnode *vnode = AFS_FS_I(mapping->host);
- struct page *pages[8], *page;
- unsigned long count, priv;
- unsigned n, offset, to, f, t;
- pgoff_t start, first, last;
- int loop, ret;
- _enter(",%lx", primary_page->index);
- count = 1;
- if (test_set_page_writeback(primary_page))
- BUG();
- /* Find all consecutive lockable dirty pages that have contiguous
- * written regions, stopping when we find a page that is not
- * immediately lockable, is not dirty or is missing, or we reach the
- * end of the range.
- */
- start = primary_page->index;
- priv = page_private(primary_page);
- offset = priv & AFS_PRIV_MAX;
- to = priv >> AFS_PRIV_SHIFT;
- trace_afs_page_dirty(vnode, tracepoint_string("store"),
- primary_page->index, priv);
- WARN_ON(offset == to);
- if (offset == to)
- trace_afs_page_dirty(vnode, tracepoint_string("WARN"),
- primary_page->index, priv);
- if (start >= final_page ||
- (to < PAGE_SIZE && !test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags)))
- goto no_more;
- start++;
- do {
- _debug("more %lx [%lx]", start, count);
- n = final_page - start + 1;
- if (n > ARRAY_SIZE(pages))
- n = ARRAY_SIZE(pages);
- n = find_get_pages_contig(mapping, start, ARRAY_SIZE(pages), pages);
- _debug("fgpc %u", n);
- if (n == 0)
- goto no_more;
- if (pages[0]->index != start) {
- do {
- put_page(pages[--n]);
- } while (n > 0);
- goto no_more;
- }
- for (loop = 0; loop < n; loop++) {
- page = pages[loop];
- if (to != PAGE_SIZE &&
- !test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags))
- break;
- if (page->index > final_page)
- break;
- if (!trylock_page(page))
- break;
- if (!PageDirty(page) || PageWriteback(page)) {
- unlock_page(page);
- break;
- }
- priv = page_private(page);
- f = priv & AFS_PRIV_MAX;
- t = priv >> AFS_PRIV_SHIFT;
- if (f != 0 &&
- !test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags)) {
- unlock_page(page);
- break;
- }
- to = t;
- trace_afs_page_dirty(vnode, tracepoint_string("store+"),
- page->index, priv);
- if (!clear_page_dirty_for_io(page))
- BUG();
- if (test_set_page_writeback(page))
- BUG();
- unlock_page(page);
- put_page(page);
- }
- count += loop;
- if (loop < n) {
- for (; loop < n; loop++)
- put_page(pages[loop]);
- goto no_more;
- }
- start += loop;
- } while (start <= final_page && count < 65536);
- no_more:
- /* We now have a contiguous set of dirty pages, each with writeback
- * set; the first page is still locked at this point, but all the rest
- * have been unlocked.
- */
- unlock_page(primary_page);
- first = primary_page->index;
- last = first + count - 1;
- _debug("write back %lx[%u..] to %lx[..%u]", first, offset, last, to);
- ret = afs_store_data(mapping, first, last, offset, to);
- switch (ret) {
- case 0:
- ret = count;
- break;
- default:
- pr_notice("kAFS: Unexpected error from FS.StoreData %d\n", ret);
- /* Fall through */
- case -EACCES:
- case -EPERM:
- case -ENOKEY:
- case -EKEYEXPIRED:
- case -EKEYREJECTED:
- case -EKEYREVOKED:
- afs_redirty_pages(wbc, mapping, first, last);
- mapping_set_error(mapping, ret);
- break;
- case -EDQUOT:
- case -ENOSPC:
- afs_redirty_pages(wbc, mapping, first, last);
- mapping_set_error(mapping, -ENOSPC);
- break;
- case -EROFS:
- case -EIO:
- case -EREMOTEIO:
- case -EFBIG:
- case -ENOENT:
- case -ENOMEDIUM:
- case -ENXIO:
- afs_kill_pages(mapping, first, last);
- mapping_set_error(mapping, ret);
- break;
- }
- _leave(" = %d", ret);
- return ret;
- }
- /*
- * write a page back to the server
- * - the caller locked the page for us
- */
- int afs_writepage(struct page *page, struct writeback_control *wbc)
- {
- int ret;
- _enter("{%lx},", page->index);
- ret = afs_write_back_from_locked_page(page->mapping, wbc, page,
- wbc->range_end >> PAGE_SHIFT);
- if (ret < 0) {
- _leave(" = %d", ret);
- return 0;
- }
- wbc->nr_to_write -= ret;
- _leave(" = 0");
- return 0;
- }
- /*
- * write a region of pages back to the server
- */
- static int afs_writepages_region(struct address_space *mapping,
- struct writeback_control *wbc,
- pgoff_t index, pgoff_t end, pgoff_t *_next)
- {
- struct page *page;
- int ret, n;
- _enter(",,%lx,%lx,", index, end);
- do {
- n = find_get_pages_range_tag(mapping, &index, end,
- PAGECACHE_TAG_DIRTY, 1, &page);
- if (!n)
- break;
- _debug("wback %lx", page->index);
- /*
- * at this point we hold neither the i_pages lock nor the
- * page lock: the page may be truncated or invalidated
- * (changing page->mapping to NULL), or even swizzled
- * back from swapper_space to tmpfs file mapping
- */
- ret = lock_page_killable(page);
- if (ret < 0) {
- put_page(page);
- _leave(" = %d", ret);
- return ret;
- }
- if (page->mapping != mapping || !PageDirty(page)) {
- unlock_page(page);
- put_page(page);
- continue;
- }
- if (PageWriteback(page)) {
- unlock_page(page);
- if (wbc->sync_mode != WB_SYNC_NONE)
- wait_on_page_writeback(page);
- put_page(page);
- continue;
- }
- if (!clear_page_dirty_for_io(page))
- BUG();
- ret = afs_write_back_from_locked_page(mapping, wbc, page, end);
- put_page(page);
- if (ret < 0) {
- _leave(" = %d", ret);
- return ret;
- }
- wbc->nr_to_write -= ret;
- cond_resched();
- } while (index < end && wbc->nr_to_write > 0);
- *_next = index;
- _leave(" = 0 [%lx]", *_next);
- return 0;
- }
- /*
- * write some of the pending data back to the server
- */
- int afs_writepages(struct address_space *mapping,
- struct writeback_control *wbc)
- {
- pgoff_t start, end, next;
- int ret;
- _enter("");
- if (wbc->range_cyclic) {
- start = mapping->writeback_index;
- end = -1;
- ret = afs_writepages_region(mapping, wbc, start, end, &next);
- if (start > 0 && wbc->nr_to_write > 0 && ret == 0)
- ret = afs_writepages_region(mapping, wbc, 0, start,
- &next);
- mapping->writeback_index = next;
- } else if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) {
- end = (pgoff_t)(LLONG_MAX >> PAGE_SHIFT);
- ret = afs_writepages_region(mapping, wbc, 0, end, &next);
- if (wbc->nr_to_write > 0)
- mapping->writeback_index = next;
- } else {
- start = wbc->range_start >> PAGE_SHIFT;
- end = wbc->range_end >> PAGE_SHIFT;
- ret = afs_writepages_region(mapping, wbc, start, end, &next);
- }
- _leave(" = %d", ret);
- return ret;
- }
- /*
- * completion of write to server
- */
- void afs_pages_written_back(struct afs_vnode *vnode, struct afs_call *call)
- {
- struct pagevec pv;
- unsigned long priv;
- unsigned count, loop;
- pgoff_t first = call->first, last = call->last;
- _enter("{%x:%u},{%lx-%lx}",
- vnode->fid.vid, vnode->fid.vnode, first, last);
- pagevec_init(&pv);
- do {
- _debug("done %lx-%lx", first, last);
- count = last - first + 1;
- if (count > PAGEVEC_SIZE)
- count = PAGEVEC_SIZE;
- pv.nr = find_get_pages_contig(vnode->vfs_inode.i_mapping,
- first, count, pv.pages);
- ASSERTCMP(pv.nr, ==, count);
- for (loop = 0; loop < count; loop++) {
- priv = page_private(pv.pages[loop]);
- trace_afs_page_dirty(vnode, tracepoint_string("clear"),
- pv.pages[loop]->index, priv);
- set_page_private(pv.pages[loop], 0);
- end_page_writeback(pv.pages[loop]);
- }
- first += count;
- __pagevec_release(&pv);
- } while (first <= last);
- afs_prune_wb_keys(vnode);
- _leave("");
- }
- /*
- * write to an AFS file
- */
- ssize_t afs_file_write(struct kiocb *iocb, struct iov_iter *from)
- {
- struct afs_vnode *vnode = AFS_FS_I(file_inode(iocb->ki_filp));
- ssize_t result;
- size_t count = iov_iter_count(from);
- _enter("{%x.%u},{%zu},",
- vnode->fid.vid, vnode->fid.vnode, count);
- if (IS_SWAPFILE(&vnode->vfs_inode)) {
- printk(KERN_INFO
- "AFS: Attempt to write to active swap file!\n");
- return -EBUSY;
- }
- if (!count)
- return 0;
- result = generic_file_write_iter(iocb, from);
- _leave(" = %zd", result);
- return result;
- }
- /*
- * flush any dirty pages for this process, and check for write errors.
- * - the return status from this call provides a reliable indication of
- * whether any write errors occurred for this process.
- */
- int afs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
- {
- struct inode *inode = file_inode(file);
- struct afs_vnode *vnode = AFS_FS_I(inode);
- _enter("{%x:%u},{n=%pD},%d",
- vnode->fid.vid, vnode->fid.vnode, file,
- datasync);
- return file_write_and_wait_range(file, start, end);
- }
- /*
- * notification that a previously read-only page is about to become writable
- * - if it returns an error, the caller will deliver a bus error signal
- */
- vm_fault_t afs_page_mkwrite(struct vm_fault *vmf)
- {
- struct file *file = vmf->vma->vm_file;
- struct inode *inode = file_inode(file);
- struct afs_vnode *vnode = AFS_FS_I(inode);
- unsigned long priv;
- _enter("{{%x:%u}},{%lx}",
- vnode->fid.vid, vnode->fid.vnode, vmf->page->index);
- sb_start_pagefault(inode->i_sb);
- /* Wait for the page to be written to the cache before we allow it to
- * be modified. We then assume the entire page will need writing back.
- */
- #ifdef CONFIG_AFS_FSCACHE
- fscache_wait_on_page_write(vnode->cache, vmf->page);
- #endif
- if (PageWriteback(vmf->page) &&
- wait_on_page_bit_killable(vmf->page, PG_writeback) < 0)
- return VM_FAULT_RETRY;
- if (lock_page_killable(vmf->page) < 0)
- return VM_FAULT_RETRY;
- /* We mustn't change page->private until writeback is complete as that
- * details the portion of the page we need to write back and we might
- * need to redirty the page if there's a problem.
- */
- wait_on_page_writeback(vmf->page);
- priv = (unsigned long)PAGE_SIZE << AFS_PRIV_SHIFT; /* To */
- priv |= 0; /* From */
- trace_afs_page_dirty(vnode, tracepoint_string("mkwrite"),
- vmf->page->index, priv);
- SetPagePrivate(vmf->page);
- set_page_private(vmf->page, priv);
- sb_end_pagefault(inode->i_sb);
- return VM_FAULT_LOCKED;
- }
- /*
- * Prune the keys cached for writeback. The caller must hold vnode->wb_lock.
- */
- void afs_prune_wb_keys(struct afs_vnode *vnode)
- {
- LIST_HEAD(graveyard);
- struct afs_wb_key *wbk, *tmp;
- /* Discard unused keys */
- spin_lock(&vnode->wb_lock);
- if (!mapping_tagged(&vnode->vfs_inode.i_data, PAGECACHE_TAG_WRITEBACK) &&
- !mapping_tagged(&vnode->vfs_inode.i_data, PAGECACHE_TAG_DIRTY)) {
- list_for_each_entry_safe(wbk, tmp, &vnode->wb_keys, vnode_link) {
- if (refcount_read(&wbk->usage) == 1)
- list_move(&wbk->vnode_link, &graveyard);
- }
- }
- spin_unlock(&vnode->wb_lock);
- while (!list_empty(&graveyard)) {
- wbk = list_entry(graveyard.next, struct afs_wb_key, vnode_link);
- list_del(&wbk->vnode_link);
- afs_put_wb_key(wbk);
- }
- }
- /*
- * Clean up a page during invalidation.
- */
- int afs_launder_page(struct page *page)
- {
- struct address_space *mapping = page->mapping;
- struct afs_vnode *vnode = AFS_FS_I(mapping->host);
- unsigned long priv;
- unsigned int f, t;
- int ret = 0;
- _enter("{%lx}", page->index);
- priv = page_private(page);
- if (clear_page_dirty_for_io(page)) {
- f = 0;
- t = PAGE_SIZE;
- if (PagePrivate(page)) {
- f = priv & AFS_PRIV_MAX;
- t = priv >> AFS_PRIV_SHIFT;
- }
- trace_afs_page_dirty(vnode, tracepoint_string("launder"),
- page->index, priv);
- ret = afs_store_data(mapping, page->index, page->index, t, f);
- }
- trace_afs_page_dirty(vnode, tracepoint_string("laundered"),
- page->index, priv);
- set_page_private(page, 0);
- ClearPagePrivate(page);
- #ifdef CONFIG_AFS_FSCACHE
- if (PageFsCache(page)) {
- fscache_wait_on_page_write(vnode->cache, page);
- fscache_uncache_page(vnode->cache, page);
- }
- #endif
- return ret;
- }
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