1 files changed, 0 insertions, 416 deletions
diff --git a/fs/fscache/cache.c b/fs/fscache/cache.c
deleted file mode 100644
index bd4f44c1cce0..000000000000
--- a/fs/fscache/cache.c
+++ /dev/null
@@ -1,416 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* FS-Cache cache handling
- *
- * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#define FSCACHE_DEBUG_LEVEL CACHE
-#include <linux/module.h>
-#include <linux/slab.h>
-#include "internal.h"
-
-LIST_HEAD(fscache_cache_list);
-DECLARE_RWSEM(fscache_addremove_sem);
-DECLARE_WAIT_QUEUE_HEAD(fscache_cache_cleared_wq);
-EXPORT_SYMBOL(fscache_cache_cleared_wq);
-
-static LIST_HEAD(fscache_cache_tag_list);
-
-/*
- * look up a cache tag
- */
-struct fscache_cache_tag *__fscache_lookup_cache_tag(const char *name)
-{
-	struct fscache_cache_tag *tag, *xtag;
-
-	/* firstly check for the existence of the tag under read lock */
-	down_read(&fscache_addremove_sem);
-
-	list_for_each_entry(tag, &fscache_cache_tag_list, link) {
-		if (strcmp(tag->name, name) == 0) {
-			atomic_inc(&tag->usage);
-			up_read(&fscache_addremove_sem);
-			return tag;
-		}
-	}
-
-	up_read(&fscache_addremove_sem);
-
-	/* the tag does not exist - create a candidate */
-	xtag = kzalloc(sizeof(*xtag) + strlen(name) + 1, GFP_KERNEL);
-	if (!xtag)
-		/* return a dummy tag if out of memory */
-		return ERR_PTR(-ENOMEM);
-
-	atomic_set(&xtag->usage, 1);
-	strcpy(xtag->name, name);
-
-	/* write lock, search again and add if still not present */
-	down_write(&fscache_addremove_sem);
-
-	list_for_each_entry(tag, &fscache_cache_tag_list, link) {
-		if (strcmp(tag->name, name) == 0) {
-			atomic_inc(&tag->usage);
-			up_write(&fscache_addremove_sem);
-			kfree(xtag);
-			return tag;
-		}
-	}
-
-	list_add_tail(&xtag->link, &fscache_cache_tag_list);
-	up_write(&fscache_addremove_sem);
-	return xtag;
-}
-
-/*
- * release a reference to a cache tag
- */
-void __fscache_release_cache_tag(struct fscache_cache_tag *tag)
-{
-	if (tag != ERR_PTR(-ENOMEM)) {
-		down_write(&fscache_addremove_sem);
-
-		if (atomic_dec_and_test(&tag->usage))
-			list_del_init(&tag->link);
-		else
-			tag = NULL;
-
-		up_write(&fscache_addremove_sem);
-
-		kfree(tag);
-	}
-}
-
-/*
- * select a cache in which to store an object
- * - the cache addremove semaphore must be at least read-locked by the caller
- * - the object will never be an index
- */
-struct fscache_cache *fscache_select_cache_for_object(
-	struct fscache_cookie *cookie)
-{
-	struct fscache_cache_tag *tag;
-	struct fscache_object *object;
-	struct fscache_cache *cache;
-
-	_enter("");
-
-	if (list_empty(&fscache_cache_list)) {
-		_leave(" = NULL [no cache]");
-		return NULL;
-	}
-
-	/* we check the parent to determine the cache to use */
-	spin_lock(&cookie->lock);
-
-	/* the first in the parent's backing list should be the preferred
-	 * cache */
-	if (!hlist_empty(&cookie->backing_objects)) {
-		object = hlist_entry(cookie->backing_objects.first,
-				     struct fscache_object, cookie_link);
-
-		cache = object->cache;
-		if (fscache_object_is_dying(object) ||
-		    test_bit(FSCACHE_IOERROR, &cache->flags))
-			cache = NULL;
-
-		spin_unlock(&cookie->lock);
-		_leave(" = %s [parent]", cache ? cache->tag->name : "NULL");
-		return cache;
-	}
-
-	/* the parent is unbacked */
-	if (cookie->type != FSCACHE_COOKIE_TYPE_INDEX) {
-		/* cookie not an index and is unbacked */
-		spin_unlock(&cookie->lock);
-		_leave(" = NULL [cookie ub,ni]");
-		return NULL;
-	}
-
-	spin_unlock(&cookie->lock);
-
-	if (!cookie->def->select_cache)
-		goto no_preference;
-
-	/* ask the netfs for its preference */
-	tag = cookie->def->select_cache(cookie->parent->netfs_data,
-					cookie->netfs_data);
-	if (!tag)
-		goto no_preference;
-
-	if (tag == ERR_PTR(-ENOMEM)) {
-		_leave(" = NULL [nomem tag]");
-		return NULL;
-	}
-
-	if (!tag->cache) {
-		_leave(" = NULL [unbacked tag]");
-		return NULL;
-	}
-
-	if (test_bit(FSCACHE_IOERROR, &tag->cache->flags))
-		return NULL;
-
-	_leave(" = %s [specific]", tag->name);
-	return tag->cache;
-
-no_preference:
-	/* netfs has no preference - just select first cache */
-	cache = list_entry(fscache_cache_list.next,
-			   struct fscache_cache, link);
-	_leave(" = %s [first]", cache->tag->name);
-	return cache;
-}
-
-/**
- * fscache_init_cache - Initialise a cache record
- * @cache: The cache record to be initialised
- * @ops: The cache operations to be installed in that record
- * @idfmt: Format string to define identifier
- * @...: sprintf-style arguments
- *
- * Initialise a record of a cache and fill in the name.
- *
- * See Documentation/filesystems/caching/backend-api.rst for a complete
- * description.
- */
-void fscache_init_cache(struct fscache_cache *cache,
-			const struct fscache_cache_ops *ops,
-			const char *idfmt,
-			...)
-{
-	va_list va;
-
-	memset(cache, 0, sizeof(*cache));
-
-	cache->ops = ops;
-
-	va_start(va, idfmt);
-	vsnprintf(cache->identifier, sizeof(cache->identifier), idfmt, va);
-	va_end(va);
-
-	INIT_WORK(&cache->op_gc, fscache_operation_gc);
-	INIT_LIST_HEAD(&cache->link);
-	INIT_LIST_HEAD(&cache->object_list);
-	INIT_LIST_HEAD(&cache->op_gc_list);
-	spin_lock_init(&cache->object_list_lock);
-	spin_lock_init(&cache->op_gc_list_lock);
-}
-EXPORT_SYMBOL(fscache_init_cache);
-
-/**
- * fscache_add_cache - Declare a cache as being open for business
- * @cache: The record describing the cache
- * @ifsdef: The record of the cache object describing the top-level index
- * @tagname: The tag describing this cache
- *
- * Add a cache to the system, making it available for netfs's to use.
- *
- * See Documentation/filesystems/caching/backend-api.rst for a complete
- * description.
- */
-int fscache_add_cache(struct fscache_cache *cache,
-		      struct fscache_object *ifsdef,
-		      const char *tagname)
-{
-	struct fscache_cache_tag *tag;
-
-	ASSERTCMP(ifsdef->cookie, ==, &fscache_fsdef_index);
-	BUG_ON(!cache->ops);
-	BUG_ON(!ifsdef);
-
-	cache->flags = 0;
-	ifsdef->event_mask =
-		((1 << NR_FSCACHE_OBJECT_EVENTS) - 1) &
-		~(1 << FSCACHE_OBJECT_EV_CLEARED);
-	__set_bit(FSCACHE_OBJECT_IS_AVAILABLE, &ifsdef->flags);
-
-	if (!tagname)
-		tagname = cache->identifier;
-
-	BUG_ON(!tagname[0]);
-
-	_enter("{%s.%s},,%s", cache->ops->name, cache->identifier, tagname);
-
-	/* we use the cache tag to uniquely identify caches */
-	tag = __fscache_lookup_cache_tag(tagname);
-	if (IS_ERR(tag))
-		goto nomem;
-
-	if (test_and_set_bit(FSCACHE_TAG_RESERVED, &tag->flags))
-		goto tag_in_use;
-
-	cache->kobj = kobject_create_and_add(tagname, fscache_root);
-	if (!cache->kobj)
-		goto error;
-
-	ifsdef->cache = cache;
-	cache->fsdef = ifsdef;
-
-	down_write(&fscache_addremove_sem);
-
-	tag->cache = cache;
-	cache->tag = tag;
-
-	/* add the cache to the list */
-	list_add(&cache->link, &fscache_cache_list);
-
-	/* add the cache's netfs definition index object to the cache's
-	 * list */
-	spin_lock(&cache->object_list_lock);
-	list_add_tail(&ifsdef->cache_link, &cache->object_list);
-	spin_unlock(&cache->object_list_lock);
-
-	/* add the cache's netfs definition index object to the top level index
-	 * cookie as a known backing object */
-	spin_lock(&fscache_fsdef_index.lock);
-
-	hlist_add_head(&ifsdef->cookie_link,
-		       &fscache_fsdef_index.backing_objects);
-
-	refcount_inc(&fscache_fsdef_index.ref);
-
-	/* done */
-	spin_unlock(&fscache_fsdef_index.lock);
-	up_write(&fscache_addremove_sem);
-
-	pr_notice("Cache \"%s\" added (type %s)\n",
-		  cache->tag->name, cache->ops->name);
-	kobject_uevent(cache->kobj, KOBJ_ADD);
-
-	_leave(" = 0 [%s]", cache->identifier);
-	return 0;
-
-tag_in_use:
-	pr_err("Cache tag '%s' already in use\n", tagname);
-	__fscache_release_cache_tag(tag);
-	_leave(" = -EXIST");
-	return -EEXIST;
-
-error:
-	__fscache_release_cache_tag(tag);
-	_leave(" = -EINVAL");
-	return -EINVAL;
-
-nomem:
-	_leave(" = -ENOMEM");
-	return -ENOMEM;
-}
-EXPORT_SYMBOL(fscache_add_cache);
-
-/**
- * fscache_io_error - Note a cache I/O error
- * @cache: The record describing the cache
- *
- * Note that an I/O error occurred in a cache and that it should no longer be
- * used for anything.  This also reports the error into the kernel log.
- *
- * See Documentation/filesystems/caching/backend-api.rst for a complete
- * description.
- */
-void fscache_io_error(struct fscache_cache *cache)
-{
-	if (!test_and_set_bit(FSCACHE_IOERROR, &cache->flags))
-		pr_err("Cache '%s' stopped due to I/O error\n",
-		       cache->ops->name);
-}
-EXPORT_SYMBOL(fscache_io_error);
-
-/*
- * request withdrawal of all the objects in a cache
- * - all the objects being withdrawn are moved onto the supplied list
- */
-static void fscache_withdraw_all_objects(struct fscache_cache *cache,
-					 struct list_head *dying_objects)
-{
-	struct fscache_object *object;
-
-	while (!list_empty(&cache->object_list)) {
-		spin_lock(&cache->object_list_lock);
-
-		if (!list_empty(&cache->object_list)) {
-			object = list_entry(cache->object_list.next,
-					    struct fscache_object, cache_link);
-			list_move_tail(&object->cache_link, dying_objects);
-
-			_debug("withdraw %x", object->cookie->debug_id);
-
-			/* This must be done under object_list_lock to prevent
-			 * a race with fscache_drop_object().
-			 */
-			fscache_raise_event(object, FSCACHE_OBJECT_EV_KILL);
-		}
-
-		spin_unlock(&cache->object_list_lock);
-		cond_resched();
-	}
-}
-
-/**
- * fscache_withdraw_cache - Withdraw a cache from the active service
- * @cache: The record describing the cache
- *
- * Withdraw a cache from service, unbinding all its cache objects from the
- * netfs cookies they're currently representing.
- *
- * See Documentation/filesystems/caching/backend-api.rst for a complete
- * description.
- */
-void fscache_withdraw_cache(struct fscache_cache *cache)
-{
-	LIST_HEAD(dying_objects);
-
-	_enter("");
-
-	pr_notice("Withdrawing cache \"%s\"\n",
-		  cache->tag->name);
-
-	/* make the cache unavailable for cookie acquisition */
-	if (test_and_set_bit(FSCACHE_CACHE_WITHDRAWN, &cache->flags))
-		BUG();
-
-	down_write(&fscache_addremove_sem);
-	list_del_init(&cache->link);
-	cache->tag->cache = NULL;
-	up_write(&fscache_addremove_sem);
-
-	/* make sure all pages pinned by operations on behalf of the netfs are
-	 * written to disk */
-	fscache_stat(&fscache_n_cop_sync_cache);
-	cache->ops->sync_cache(cache);
-	fscache_stat_d(&fscache_n_cop_sync_cache);
-
-	/* dissociate all the netfs pages backed by this cache from the block
-	 * mappings in the cache */
-	fscache_stat(&fscache_n_cop_dissociate_pages);
-	cache->ops->dissociate_pages(cache);
-	fscache_stat_d(&fscache_n_cop_dissociate_pages);
-
-	/* we now have to destroy all the active objects pertaining to this
-	 * cache - which we do by passing them off to thread pool to be
-	 * disposed of */
-	_debug("destroy");
-
-	fscache_withdraw_all_objects(cache, &dying_objects);
-
-	/* wait for all extant objects to finish their outstanding operations
-	 * and go away */
-	_debug("wait for finish");
-	wait_event(fscache_cache_cleared_wq,
-		   atomic_read(&cache->object_count) == 0);
-	_debug("wait for clearance");
-	wait_event(fscache_cache_cleared_wq,
-		   list_empty(&cache->object_list));
-	_debug("cleared");
-	ASSERT(list_empty(&dying_objects));
-
-	kobject_put(cache->kobj);
-
-	clear_bit(FSCACHE_TAG_RESERVED, &cache->tag->flags);
-	fscache_release_cache_tag(cache->tag);
-	cache->tag = NULL;
-
-	_leave("");
-}
-EXPORT_SYMBOL(fscache_withdraw_cache);