Moved, renamed, and deleted files

The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.

1 files changed, 0 insertions, 984 deletions

diff --git a/ANDROID_3.4.5/fs/cachefiles/rdwr.c b/ANDROID_3.4.5/fs/cachefiles/rdwr.c
deleted file mode 100644
index 0e3c0924..00000000
--- a/ANDROID_3.4.5/fs/cachefiles/rdwr.c
+++ /dev/null
@@ -1,984 +0,0 @@
-/* Storage object read/write
- *
- * 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 Licence
- * as published by the Free Software Foundation; either version
- * 2 of the Licence, or (at your option) any later version.
- */
-
-#include <linux/mount.h>
-#include <linux/slab.h>
-#include <linux/file.h>
-#include "internal.h"
-
-/*
- * detect wake up events generated by the unlocking of pages in which we're
- * interested
- * - we use this to detect read completion of backing pages
- * - the caller holds the waitqueue lock
- */
-static int cachefiles_read_waiter(wait_queue_t *wait, unsigned mode,
-				  int sync, void *_key)
-{
-	struct cachefiles_one_read *monitor =
-		container_of(wait, struct cachefiles_one_read, monitor);
-	struct cachefiles_object *object;
-	struct wait_bit_key *key = _key;
-	struct page *page = wait->private;
-
-	ASSERT(key);
-
-	_enter("{%lu},%u,%d,{%p,%u}",
-	       monitor->netfs_page->index, mode, sync,
-	       key->flags, key->bit_nr);
-
-	if (key->flags != &page->flags ||
-	    key->bit_nr != PG_locked)
-		return 0;
-
-	_debug("--- monitor %p %lx ---", page, page->flags);
-
-	if (!PageUptodate(page) && !PageError(page)) {
-		/* unlocked, not uptodate and not erronous? */
-		_debug("page probably truncated");
-	}
-
-	/* remove from the waitqueue */
-	list_del(&wait->task_list);
-
-	/* move onto the action list and queue for FS-Cache thread pool */
-	ASSERT(monitor->op);
-
-	object = container_of(monitor->op->op.object,
-			      struct cachefiles_object, fscache);
-
-	spin_lock(&object->work_lock);
-	list_add_tail(&monitor->op_link, &monitor->op->to_do);
-	spin_unlock(&object->work_lock);
-
-	fscache_enqueue_retrieval(monitor->op);
-	return 0;
-}
-
-/*
- * handle a probably truncated page
- * - check to see if the page is still relevant and reissue the read if
- *   possible
- * - return -EIO on error, -ENODATA if the page is gone, -EINPROGRESS if we
- *   must wait again and 0 if successful
- */
-static int cachefiles_read_reissue(struct cachefiles_object *object,
-				   struct cachefiles_one_read *monitor)
-{
-	struct address_space *bmapping = object->backer->d_inode->i_mapping;
-	struct page *backpage = monitor->back_page, *backpage2;
-	int ret;
-
-	kenter("{ino=%lx},{%lx,%lx}",
-	       object->backer->d_inode->i_ino,
-	       backpage->index, backpage->flags);
-
-	/* skip if the page was truncated away completely */
-	if (backpage->mapping != bmapping) {
-		kleave(" = -ENODATA [mapping]");
-		return -ENODATA;
-	}
-
-	backpage2 = find_get_page(bmapping, backpage->index);
-	if (!backpage2) {
-		kleave(" = -ENODATA [gone]");
-		return -ENODATA;
-	}
-
-	if (backpage != backpage2) {
-		put_page(backpage2);
-		kleave(" = -ENODATA [different]");
-		return -ENODATA;
-	}
-
-	/* the page is still there and we already have a ref on it, so we don't
-	 * need a second */
-	put_page(backpage2);
-
-	INIT_LIST_HEAD(&monitor->op_link);
-	add_page_wait_queue(backpage, &monitor->monitor);
-
-	if (trylock_page(backpage)) {
-		ret = -EIO;
-		if (PageError(backpage))
-			goto unlock_discard;
-		ret = 0;
-		if (PageUptodate(backpage))
-			goto unlock_discard;
-
-		kdebug("reissue read");
-		ret = bmapping->a_ops->readpage(NULL, backpage);
-		if (ret < 0)
-			goto unlock_discard;
-	}
-
-	/* but the page may have been read before the monitor was installed, so
-	 * the monitor may miss the event - so we have to ensure that we do get
-	 * one in such a case */
-	if (trylock_page(backpage)) {
-		_debug("jumpstart %p {%lx}", backpage, backpage->flags);
-		unlock_page(backpage);
-	}
-
-	/* it'll reappear on the todo list */
-	kleave(" = -EINPROGRESS");
-	return -EINPROGRESS;
-
-unlock_discard:
-	unlock_page(backpage);
-	spin_lock_irq(&object->work_lock);
-	list_del(&monitor->op_link);
-	spin_unlock_irq(&object->work_lock);
-	kleave(" = %d", ret);
-	return ret;
-}
-
-/*
- * copy data from backing pages to netfs pages to complete a read operation
- * - driven by FS-Cache's thread pool
- */
-static void cachefiles_read_copier(struct fscache_operation *_op)
-{
-	struct cachefiles_one_read *monitor;
-	struct cachefiles_object *object;
-	struct fscache_retrieval *op;
-	struct pagevec pagevec;
-	int error, max;
-
-	op = container_of(_op, struct fscache_retrieval, op);
-	object = container_of(op->op.object,
-			      struct cachefiles_object, fscache);
-
-	_enter("{ino=%lu}", object->backer->d_inode->i_ino);
-
-	pagevec_init(&pagevec, 0);
-
-	max = 8;
-	spin_lock_irq(&object->work_lock);
-
-	while (!list_empty(&op->to_do)) {
-		monitor = list_entry(op->to_do.next,
-				     struct cachefiles_one_read, op_link);
-		list_del(&monitor->op_link);
-
-		spin_unlock_irq(&object->work_lock);
-
-		_debug("- copy {%lu}", monitor->back_page->index);
-
-	recheck:
-		if (PageUptodate(monitor->back_page)) {
-			copy_highpage(monitor->netfs_page, monitor->back_page);
-
-			pagevec_add(&pagevec, monitor->netfs_page);
-			fscache_mark_pages_cached(monitor->op, &pagevec);
-			error = 0;
-		} else if (!PageError(monitor->back_page)) {
-			/* the page has probably been truncated */
-			error = cachefiles_read_reissue(object, monitor);
-			if (error == -EINPROGRESS)
-				goto next;
-			goto recheck;
-		} else {
-			cachefiles_io_error_obj(
-				object,
-				"Readpage failed on backing file %lx",
-				(unsigned long) monitor->back_page->flags);
-			error = -EIO;
-		}
-
-		page_cache_release(monitor->back_page);
-
-		fscache_end_io(op, monitor->netfs_page, error);
-		page_cache_release(monitor->netfs_page);
-		fscache_put_retrieval(op);
-		kfree(monitor);
-
-	next:
-		/* let the thread pool have some air occasionally */
-		max--;
-		if (max < 0 || need_resched()) {
-			if (!list_empty(&op->to_do))
-				fscache_enqueue_retrieval(op);
-			_leave(" [maxed out]");
-			return;
-		}
-
-		spin_lock_irq(&object->work_lock);
-	}
-
-	spin_unlock_irq(&object->work_lock);
-	_leave("");
-}
-
-/*
- * read the corresponding page to the given set from the backing file
- * - an uncertain page is simply discarded, to be tried again another time
- */
-static int cachefiles_read_backing_file_one(struct cachefiles_object *object,
-					    struct fscache_retrieval *op,
-					    struct page *netpage,
-					    struct pagevec *pagevec)
-{
-	struct cachefiles_one_read *monitor;
-	struct address_space *bmapping;
-	struct page *newpage, *backpage;
-	int ret;
-
-	_enter("");
-
-	pagevec_reinit(pagevec);
-
-	_debug("read back %p{%lu,%d}",
-	       netpage, netpage->index, page_count(netpage));
-
-	monitor = kzalloc(sizeof(*monitor), GFP_KERNEL);
-	if (!monitor)
-		goto nomem;
-
-	monitor->netfs_page = netpage;
-	monitor->op = fscache_get_retrieval(op);
-
-	init_waitqueue_func_entry(&monitor->monitor, cachefiles_read_waiter);
-
-	/* attempt to get hold of the backing page */
-	bmapping = object->backer->d_inode->i_mapping;
-	newpage = NULL;
-
-	for (;;) {
-		backpage = find_get_page(bmapping, netpage->index);
-		if (backpage)
-			goto backing_page_already_present;
-
-		if (!newpage) {
-			newpage = page_cache_alloc_cold(bmapping);
-			if (!newpage)
-				goto nomem_monitor;
-		}
-
-		ret = add_to_page_cache(newpage, bmapping,
-					netpage->index, GFP_KERNEL);
-		if (ret == 0)
-			goto installed_new_backing_page;
-		if (ret != -EEXIST)
-			goto nomem_page;
-	}
-
-	/* we've installed a new backing page, so now we need to add it
-	 * to the LRU list and start it reading */
-installed_new_backing_page:
-	_debug("- new %p", newpage);
-
-	backpage = newpage;
-	newpage = NULL;
-
-	page_cache_get(backpage);
-	pagevec_add(pagevec, backpage);
-	__pagevec_lru_add_file(pagevec);
-
-read_backing_page:
-	ret = bmapping->a_ops->readpage(NULL, backpage);
-	if (ret < 0)
-		goto read_error;
-
-	/* set the monitor to transfer the data across */
-monitor_backing_page:
-	_debug("- monitor add");
-
-	/* install the monitor */
-	page_cache_get(monitor->netfs_page);
-	page_cache_get(backpage);
-	monitor->back_page = backpage;
-	monitor->monitor.private = backpage;
-	add_page_wait_queue(backpage, &monitor->monitor);
-	monitor = NULL;
-
-	/* but the page may have been read before the monitor was installed, so
-	 * the monitor may miss the event - so we have to ensure that we do get
-	 * one in such a case */
-	if (trylock_page(backpage)) {
-		_debug("jumpstart %p {%lx}", backpage, backpage->flags);
-		unlock_page(backpage);
-	}
-	goto success;
-
-	/* if the backing page is already present, it can be in one of
-	 * three states: read in progress, read failed or read okay */
-backing_page_already_present:
-	_debug("- present");
-
-	if (newpage) {
-		page_cache_release(newpage);
-		newpage = NULL;
-	}
-
-	if (PageError(backpage))
-		goto io_error;
-
-	if (PageUptodate(backpage))
-		goto backing_page_already_uptodate;
-
-	if (!trylock_page(backpage))
-		goto monitor_backing_page;
-	_debug("read %p {%lx}", backpage, backpage->flags);
-	goto read_backing_page;
-
-	/* the backing page is already up to date, attach the netfs
-	 * page to the pagecache and LRU and copy the data across */
-backing_page_already_uptodate:
-	_debug("- uptodate");
-
-	pagevec_add(pagevec, netpage);
-	fscache_mark_pages_cached(op, pagevec);
-
-	copy_highpage(netpage, backpage);
-	fscache_end_io(op, netpage, 0);
-
-success:
-	_debug("success");
-	ret = 0;
-
-out:
-	if (backpage)
-		page_cache_release(backpage);
-	if (monitor) {
-		fscache_put_retrieval(monitor->op);
-		kfree(monitor);
-	}
-	_leave(" = %d", ret);
-	return ret;
-
-read_error:
-	_debug("read error %d", ret);
-	if (ret == -ENOMEM)
-		goto out;
-io_error:
-	cachefiles_io_error_obj(object, "Page read error on backing file");
-	ret = -ENOBUFS;
-	goto out;
-
-nomem_page:
-	page_cache_release(newpage);
-nomem_monitor:
-	fscache_put_retrieval(monitor->op);
-	kfree(monitor);
-nomem:
-	_leave(" = -ENOMEM");
-	return -ENOMEM;
-}
-
-/*
- * read a page from the cache or allocate a block in which to store it
- * - cache withdrawal is prevented by the caller
- * - returns -EINTR if interrupted
- * - returns -ENOMEM if ran out of memory
- * - returns -ENOBUFS if no buffers can be made available
- * - returns -ENOBUFS if page is beyond EOF
- * - if the page is backed by a block in the cache:
- *   - a read will be started which will call the callback on completion
- *   - 0 will be returned
- * - else if the page is unbacked:
- *   - the metadata will be retained
- *   - -ENODATA will be returned
- */
-int cachefiles_read_or_alloc_page(struct fscache_retrieval *op,
-				  struct page *page,
-				  gfp_t gfp)
-{
-	struct cachefiles_object *object;
-	struct cachefiles_cache *cache;
-	struct pagevec pagevec;
-	struct inode *inode;
-	sector_t block0, block;
-	unsigned shift;
-	int ret;
-
-	object = container_of(op->op.object,
-			      struct cachefiles_object, fscache);
-	cache = container_of(object->fscache.cache,
-			     struct cachefiles_cache, cache);
-
-	_enter("{%p},{%lx},,,", object, page->index);
-
-	if (!object->backer)
-		return -ENOBUFS;
-
-	inode = object->backer->d_inode;
-	ASSERT(S_ISREG(inode->i_mode));
-	ASSERT(inode->i_mapping->a_ops->bmap);
-	ASSERT(inode->i_mapping->a_ops->readpages);
-
-	/* calculate the shift required to use bmap */
-	if (inode->i_sb->s_blocksize > PAGE_SIZE)
-		return -ENOBUFS;
-
-	shift = PAGE_SHIFT - inode->i_sb->s_blocksize_bits;
-
-	op->op.flags &= FSCACHE_OP_KEEP_FLAGS;
-	op->op.flags |= FSCACHE_OP_ASYNC;
-	op->op.processor = cachefiles_read_copier;
-
-	pagevec_init(&pagevec, 0);
-
-	/* we assume the absence or presence of the first block is a good
-	 * enough indication for the page as a whole
-	 * - TODO: don't use bmap() for this as it is _not_ actually good
-	 *   enough for this as it doesn't indicate errors, but it's all we've
-	 *   got for the moment
-	 */
-	block0 = page->index;
-	block0 <<= shift;
-
-	block = inode->i_mapping->a_ops->bmap(inode->i_mapping, block0);
-	_debug("%llx -> %llx",
-	       (unsigned long long) block0,
-	       (unsigned long long) block);
-
-	if (block) {
-		/* submit the apparently valid page to the backing fs to be
-		 * read from disk */
-		ret = cachefiles_read_backing_file_one(object, op, page,
-						       &pagevec);
-	} else if (cachefiles_has_space(cache, 0, 1) == 0) {
-		/* there's space in the cache we can use */
-		pagevec_add(&pagevec, page);
-		fscache_mark_pages_cached(op, &pagevec);
-		ret = -ENODATA;
-	} else {
-		ret = -ENOBUFS;
-	}
-
-	_leave(" = %d", ret);
-	return ret;
-}
-
-/*
- * read the corresponding pages to the given set from the backing file
- * - any uncertain pages are simply discarded, to be tried again another time
- */
-static int cachefiles_read_backing_file(struct cachefiles_object *object,
-					struct fscache_retrieval *op,
-					struct list_head *list,
-					struct pagevec *mark_pvec)
-{
-	struct cachefiles_one_read *monitor = NULL;
-	struct address_space *bmapping = object->backer->d_inode->i_mapping;
-	struct pagevec lru_pvec;
-	struct page *newpage = NULL, *netpage, *_n, *backpage = NULL;
-	int ret = 0;
-
-	_enter("");
-
-	pagevec_init(&lru_pvec, 0);
-
-	list_for_each_entry_safe(netpage, _n, list, lru) {
-		list_del(&netpage->lru);
-
-		_debug("read back %p{%lu,%d}",
-		       netpage, netpage->index, page_count(netpage));
-
-		if (!monitor) {
-			monitor = kzalloc(sizeof(*monitor), GFP_KERNEL);
-			if (!monitor)
-				goto nomem;
-
-			monitor->op = fscache_get_retrieval(op);
-			init_waitqueue_func_entry(&monitor->monitor,
-						  cachefiles_read_waiter);
-		}
-
-		for (;;) {
-			backpage = find_get_page(bmapping, netpage->index);
-			if (backpage)
-				goto backing_page_already_present;
-
-			if (!newpage) {
-				newpage = page_cache_alloc_cold(bmapping);
-				if (!newpage)
-					goto nomem;
-			}
-
-			ret = add_to_page_cache(newpage, bmapping,
-						netpage->index, GFP_KERNEL);
-			if (ret == 0)
-				goto installed_new_backing_page;
-			if (ret != -EEXIST)
-				goto nomem;
-		}
-
-		/* we've installed a new backing page, so now we need to add it
-		 * to the LRU list and start it reading */
-	installed_new_backing_page:
-		_debug("- new %p", newpage);
-
-		backpage = newpage;
-		newpage = NULL;
-
-		page_cache_get(backpage);
-		if (!pagevec_add(&lru_pvec, backpage))
-			__pagevec_lru_add_file(&lru_pvec);
-
-	reread_backing_page:
-		ret = bmapping->a_ops->readpage(NULL, backpage);
-		if (ret < 0)
-			goto read_error;
-
-		/* add the netfs page to the pagecache and LRU, and set the
-		 * monitor to transfer the data across */
-	monitor_backing_page:
-		_debug("- monitor add");
-
-		ret = add_to_page_cache(netpage, op->mapping, netpage->index,
-					GFP_KERNEL);
-		if (ret < 0) {
-			if (ret == -EEXIST) {
-				page_cache_release(netpage);
-				continue;
-			}
-			goto nomem;
-		}
-
-		page_cache_get(netpage);
-		if (!pagevec_add(&lru_pvec, netpage))
-			__pagevec_lru_add_file(&lru_pvec);
-
-		/* install a monitor */
-		page_cache_get(netpage);
-		monitor->netfs_page = netpage;
-
-		page_cache_get(backpage);
-		monitor->back_page = backpage;
-		monitor->monitor.private = backpage;
-		add_page_wait_queue(backpage, &monitor->monitor);
-		monitor = NULL;
-
-		/* but the page may have been read before the monitor was
-		 * installed, so the monitor may miss the event - so we have to
-		 * ensure that we do get one in such a case */
-		if (trylock_page(backpage)) {
-			_debug("2unlock %p {%lx}", backpage, backpage->flags);
-			unlock_page(backpage);
-		}
-
-		page_cache_release(backpage);
-		backpage = NULL;
-
-		page_cache_release(netpage);
-		netpage = NULL;
-		continue;
-
-		/* if the backing page is already present, it can be in one of
-		 * three states: read in progress, read failed or read okay */
-	backing_page_already_present:
-		_debug("- present %p", backpage);
-
-		if (PageError(backpage))
-			goto io_error;
-
-		if (PageUptodate(backpage))
-			goto backing_page_already_uptodate;
-
-		_debug("- not ready %p{%lx}", backpage, backpage->flags);
-
-		if (!trylock_page(backpage))
-			goto monitor_backing_page;
-
-		if (PageError(backpage)) {
-			_debug("error %lx", backpage->flags);
-			unlock_page(backpage);
-			goto io_error;
-		}
-
-		if (PageUptodate(backpage))
-			goto backing_page_already_uptodate_unlock;
-
-		/* we've locked a page that's neither up to date nor erroneous,
-		 * so we need to attempt to read it again */
-		goto reread_backing_page;
-
-		/* the backing page is already up to date, attach the netfs
-		 * page to the pagecache and LRU and copy the data across */
-	backing_page_already_uptodate_unlock:
-		_debug("uptodate %lx", backpage->flags);
-		unlock_page(backpage);
-	backing_page_already_uptodate:
-		_debug("- uptodate");
-
-		ret = add_to_page_cache(netpage, op->mapping, netpage->index,
-					GFP_KERNEL);
-		if (ret < 0) {
-			if (ret == -EEXIST) {
-				page_cache_release(netpage);
-				continue;
-			}
-			goto nomem;
-		}
-
-		copy_highpage(netpage, backpage);
-
-		page_cache_release(backpage);
-		backpage = NULL;
-
-		if (!pagevec_add(mark_pvec, netpage))
-			fscache_mark_pages_cached(op, mark_pvec);
-
-		page_cache_get(netpage);
-		if (!pagevec_add(&lru_pvec, netpage))
-			__pagevec_lru_add_file(&lru_pvec);
-
-		fscache_end_io(op, netpage, 0);
-		page_cache_release(netpage);
-		netpage = NULL;
-		continue;
-	}
-
-	netpage = NULL;
-
-	_debug("out");
-
-out:
-	/* tidy up */
-	pagevec_lru_add_file(&lru_pvec);
-
-	if (newpage)
-		page_cache_release(newpage);
-	if (netpage)
-		page_cache_release(netpage);
-	if (backpage)
-		page_cache_release(backpage);
-	if (monitor) {
-		fscache_put_retrieval(op);
-		kfree(monitor);
-	}
-
-	list_for_each_entry_safe(netpage, _n, list, lru) {
-		list_del(&netpage->lru);
-		page_cache_release(netpage);
-	}
-
-	_leave(" = %d", ret);
-	return ret;
-
-nomem:
-	_debug("nomem");
-	ret = -ENOMEM;
-	goto out;
-
-read_error:
-	_debug("read error %d", ret);
-	if (ret == -ENOMEM)
-		goto out;
-io_error:
-	cachefiles_io_error_obj(object, "Page read error on backing file");
-	ret = -ENOBUFS;
-	goto out;
-}
-
-/*
- * read a list of pages from the cache or allocate blocks in which to store
- * them
- */
-int cachefiles_read_or_alloc_pages(struct fscache_retrieval *op,
-				   struct list_head *pages,
-				   unsigned *nr_pages,
-				   gfp_t gfp)
-{
-	struct cachefiles_object *object;
-	struct cachefiles_cache *cache;
-	struct list_head backpages;
-	struct pagevec pagevec;
-	struct inode *inode;
-	struct page *page, *_n;
-	unsigned shift, nrbackpages;
-	int ret, ret2, space;
-
-	object = container_of(op->op.object,
-			      struct cachefiles_object, fscache);
-	cache = container_of(object->fscache.cache,
-			     struct cachefiles_cache, cache);
-
-	_enter("{OBJ%x,%d},,%d,,",
-	       object->fscache.debug_id, atomic_read(&op->op.usage),
-	       *nr_pages);
-
-	if (!object->backer)
-		return -ENOBUFS;
-
-	space = 1;
-	if (cachefiles_has_space(cache, 0, *nr_pages) < 0)
-		space = 0;
-
-	inode = object->backer->d_inode;
-	ASSERT(S_ISREG(inode->i_mode));
-	ASSERT(inode->i_mapping->a_ops->bmap);
-	ASSERT(inode->i_mapping->a_ops->readpages);
-
-	/* calculate the shift required to use bmap */
-	if (inode->i_sb->s_blocksize > PAGE_SIZE)
-		return -ENOBUFS;
-
-	shift = PAGE_SHIFT - inode->i_sb->s_blocksize_bits;
-
-	pagevec_init(&pagevec, 0);
-
-	op->op.flags &= FSCACHE_OP_KEEP_FLAGS;
-	op->op.flags |= FSCACHE_OP_ASYNC;
-	op->op.processor = cachefiles_read_copier;
-
-	INIT_LIST_HEAD(&backpages);
-	nrbackpages = 0;
-
-	ret = space ? -ENODATA : -ENOBUFS;
-	list_for_each_entry_safe(page, _n, pages, lru) {
-		sector_t block0, block;
-
-		/* we assume the absence or presence of the first block is a
-		 * good enough indication for the page as a whole
-		 * - TODO: don't use bmap() for this as it is _not_ actually
-		 *   good enough for this as it doesn't indicate errors, but
-		 *   it's all we've got for the moment
-		 */
-		block0 = page->index;
-		block0 <<= shift;
-
-		block = inode->i_mapping->a_ops->bmap(inode->i_mapping,
-						      block0);
-		_debug("%llx -> %llx",
-		       (unsigned long long) block0,
-		       (unsigned long long) block);
-
-		if (block) {
-			/* we have data - add it to the list to give to the
-			 * backing fs */
-			list_move(&page->lru, &backpages);
-			(*nr_pages)--;
-			nrbackpages++;
-		} else if (space && pagevec_add(&pagevec, page) == 0) {
-			fscache_mark_pages_cached(op, &pagevec);
-			ret = -ENODATA;
-		}
-	}
-
-	if (pagevec_count(&pagevec) > 0)
-		fscache_mark_pages_cached(op, &pagevec);
-
-	if (list_empty(pages))
-		ret = 0;
-
-	/* submit the apparently valid pages to the backing fs to be read from
-	 * disk */
-	if (nrbackpages > 0) {
-		ret2 = cachefiles_read_backing_file(object, op, &backpages,
-						    &pagevec);
-		if (ret2 == -ENOMEM || ret2 == -EINTR)
-			ret = ret2;
-	}
-
-	if (pagevec_count(&pagevec) > 0)
-		fscache_mark_pages_cached(op, &pagevec);
-
-	_leave(" = %d [nr=%u%s]",
-	       ret, *nr_pages, list_empty(pages) ? " empty" : "");
-	return ret;
-}
-
-/*
- * allocate a block in the cache in which to store a page
- * - cache withdrawal is prevented by the caller
- * - returns -EINTR if interrupted
- * - returns -ENOMEM if ran out of memory
- * - returns -ENOBUFS if no buffers can be made available
- * - returns -ENOBUFS if page is beyond EOF
- * - otherwise:
- *   - the metadata will be retained
- *   - 0 will be returned
- */
-int cachefiles_allocate_page(struct fscache_retrieval *op,
-			     struct page *page,
-			     gfp_t gfp)
-{
-	struct cachefiles_object *object;
-	struct cachefiles_cache *cache;
-	struct pagevec pagevec;
-	int ret;
-
-	object = container_of(op->op.object,
-			      struct cachefiles_object, fscache);
-	cache = container_of(object->fscache.cache,
-			     struct cachefiles_cache, cache);
-
-	_enter("%p,{%lx},", object, page->index);
-
-	ret = cachefiles_has_space(cache, 0, 1);
-	if (ret == 0) {
-		pagevec_init(&pagevec, 0);
-		pagevec_add(&pagevec, page);
-		fscache_mark_pages_cached(op, &pagevec);
-	} else {
-		ret = -ENOBUFS;
-	}
-
-	_leave(" = %d", ret);
-	return ret;
-}
-
-/*
- * allocate blocks in the cache in which to store a set of pages
- * - cache withdrawal is prevented by the caller
- * - returns -EINTR if interrupted
- * - returns -ENOMEM if ran out of memory
- * - returns -ENOBUFS if some buffers couldn't be made available
- * - returns -ENOBUFS if some pages are beyond EOF
- * - otherwise:
- *   - -ENODATA will be returned
- * - metadata will be retained for any page marked
- */
-int cachefiles_allocate_pages(struct fscache_retrieval *op,
-			      struct list_head *pages,
-			      unsigned *nr_pages,
-			      gfp_t gfp)
-{
-	struct cachefiles_object *object;
-	struct cachefiles_cache *cache;
-	struct pagevec pagevec;
-	struct page *page;
-	int ret;
-
-	object = container_of(op->op.object,
-			      struct cachefiles_object, fscache);
-	cache = container_of(object->fscache.cache,
-			     struct cachefiles_cache, cache);
-
-	_enter("%p,,,%d,", object, *nr_pages);
-
-	ret = cachefiles_has_space(cache, 0, *nr_pages);
-	if (ret == 0) {
-		pagevec_init(&pagevec, 0);
-
-		list_for_each_entry(page, pages, lru) {
-			if (pagevec_add(&pagevec, page) == 0)
-				fscache_mark_pages_cached(op, &pagevec);
-		}
-
-		if (pagevec_count(&pagevec) > 0)
-			fscache_mark_pages_cached(op, &pagevec);
-		ret = -ENODATA;
-	} else {
-		ret = -ENOBUFS;
-	}
-
-	_leave(" = %d", ret);
-	return ret;
-}
-
-/*
- * request a page be stored in the cache
- * - cache withdrawal is prevented by the caller
- * - this request may be ignored if there's no cache block available, in which
- *   case -ENOBUFS will be returned
- * - if the op is in progress, 0 will be returned
- */
-int cachefiles_write_page(struct fscache_storage *op, struct page *page)
-{
-	struct cachefiles_object *object;
-	struct cachefiles_cache *cache;
-	mm_segment_t old_fs;
-	struct file *file;
-	loff_t pos, eof;
-	size_t len;
-	void *data;
-	int ret;
-
-	ASSERT(op != NULL);
-	ASSERT(page != NULL);
-
-	object = container_of(op->op.object,
-			      struct cachefiles_object, fscache);
-
-	_enter("%p,%p{%lx},,,", object, page, page->index);
-
-	if (!object->backer) {
-		_leave(" = -ENOBUFS");
-		return -ENOBUFS;
-	}
-
-	ASSERT(S_ISREG(object->backer->d_inode->i_mode));
-
-	cache = container_of(object->fscache.cache,
-			     struct cachefiles_cache, cache);
-
-	/* write the page to the backing filesystem and let it store it in its
-	 * own time */
-	dget(object->backer);
-	mntget(cache->mnt);
-	file = dentry_open(object->backer, cache->mnt, O_RDWR,
-			   cache->cache_cred);
-	if (IS_ERR(file)) {
-		ret = PTR_ERR(file);
-	} else {
-		ret = -EIO;
-		if (file->f_op->write) {
-			pos = (loff_t) page->index << PAGE_SHIFT;
-
-			/* we mustn't write more data than we have, so we have
-			 * to beware of a partial page at EOF */
-			eof = object->fscache.store_limit_l;
-			len = PAGE_SIZE;
-			if (eof & ~PAGE_MASK) {
-				ASSERTCMP(pos, <, eof);
-				if (eof - pos < PAGE_SIZE) {
-					_debug("cut short %llx to %llx",
-					       pos, eof);
-					len = eof - pos;
-					ASSERTCMP(pos + len, ==, eof);
-				}
-			}
-
-			data = kmap(page);
-			old_fs = get_fs();
-			set_fs(KERNEL_DS);
-			ret = file->f_op->write(
-				file, (const void __user *) data, len, &pos);
-			set_fs(old_fs);
-			kunmap(page);
-			if (ret != len)
-				ret = -EIO;
-		}
-		fput(file);
-	}
-
-	if (ret < 0) {
-		if (ret == -EIO)
-			cachefiles_io_error_obj(
-				object, "Write page to backing file failed");
-		ret = -ENOBUFS;
-	}
-
-	_leave(" = %d", ret);
-	return ret;
-}
-
-/*
- * detach a backing block from a page
- * - cache withdrawal is prevented by the caller
- */
-void cachefiles_uncache_page(struct fscache_object *_object, struct page *page)
-{
-	struct cachefiles_object *object;
-	struct cachefiles_cache *cache;
-
-	object = container_of(_object, struct cachefiles_object, fscache);
-	cache = container_of(object->fscache.cache,
-			     struct cachefiles_cache, cache);
-
-	_enter("%p,{%lu}", object, page->index);
-
-	spin_unlock(&object->fscache.cookie->lock);
-}