Adding upstream version 6.8.9.upstream/6.8.9

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

10 files changed, 0 insertions, 3066 deletions

diff --git a/fs/fscache/Kconfig b/fs/fscache/Kconfig
deleted file mode 100644
index b313a978ae..0000000000
--- a/fs/fscache/Kconfig
+++ /dev/null
@@ -1,40 +0,0 @@
-# SPDX-License-Identifier: GPL-2.0-only
-
-config FSCACHE
-	tristate "General filesystem local caching manager"
-	select NETFS_SUPPORT
-	help
-	  This option enables a generic filesystem caching manager that can be
-	  used by various network and other filesystems to cache data locally.
-	  Different sorts of caches can be plugged in, depending on the
-	  resources available.
-
-	  See Documentation/filesystems/caching/fscache.rst for more information.
-
-config FSCACHE_STATS
-	bool "Gather statistical information on local caching"
-	depends on FSCACHE && PROC_FS
-	select NETFS_STATS
-	help
-	  This option causes statistical information to be gathered on local
-	  caching and exported through file:
-
-		/proc/fs/fscache/stats
-
-	  The gathering of statistics adds a certain amount of overhead to
-	  execution as there are a quite a few stats gathered, and on a
-	  multi-CPU system these may be on cachelines that keep bouncing
-	  between CPUs.  On the other hand, the stats are very useful for
-	  debugging purposes.  Saying 'Y' here is recommended.
-
-	  See Documentation/filesystems/caching/fscache.rst for more information.
-
-config FSCACHE_DEBUG
-	bool "Debug FS-Cache"
-	depends on FSCACHE
-	help
-	  This permits debugging to be dynamically enabled in the local caching
-	  management module.  If this is set, the debugging output may be
-	  enabled by setting bits in /sys/modules/fscache/parameter/debug.
-
-	  See Documentation/filesystems/caching/fscache.rst for more information.
diff --git a/fs/fscache/Makefile b/fs/fscache/Makefile
deleted file mode 100644
index afb090ea16..0000000000
--- a/fs/fscache/Makefile
+++ /dev/null
@@ -1,16 +0,0 @@
-# SPDX-License-Identifier: GPL-2.0
-#
-# Makefile for general filesystem caching code
-#
-
-fscache-y := \
-	cache.o \
-	cookie.o \
-	io.o \
-	main.o \
-	volume.o
-
-fscache-$(CONFIG_PROC_FS) += proc.o
-fscache-$(CONFIG_FSCACHE_STATS) += stats.o
-
-obj-$(CONFIG_FSCACHE) := fscache.o
diff --git a/fs/fscache/cache.c b/fs/fscache/cache.c
deleted file mode 100644
index 9397ed39b0..0000000000
--- a/fs/fscache/cache.c
+++ /dev/null
@@ -1,429 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* FS-Cache cache handling
- *
- * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#define FSCACHE_DEBUG_LEVEL CACHE
-#include <linux/export.h>
-#include <linux/slab.h>
-#include "internal.h"
-
-static LIST_HEAD(fscache_caches);
-DECLARE_RWSEM(fscache_addremove_sem);
-EXPORT_SYMBOL(fscache_addremove_sem);
-DECLARE_WAIT_QUEUE_HEAD(fscache_clearance_waiters);
-EXPORT_SYMBOL(fscache_clearance_waiters);
-
-static atomic_t fscache_cache_debug_id;
-
-/*
- * Allocate a cache cookie.
- */
-static struct fscache_cache *fscache_alloc_cache(const char *name)
-{
-	struct fscache_cache *cache;
-
-	cache = kzalloc(sizeof(*cache), GFP_KERNEL);
-	if (cache) {
-		if (name) {
-			cache->name = kstrdup(name, GFP_KERNEL);
-			if (!cache->name) {
-				kfree(cache);
-				return NULL;
-			}
-		}
-		refcount_set(&cache->ref, 1);
-		INIT_LIST_HEAD(&cache->cache_link);
-		cache->debug_id = atomic_inc_return(&fscache_cache_debug_id);
-	}
-	return cache;
-}
-
-static bool fscache_get_cache_maybe(struct fscache_cache *cache,
-				    enum fscache_cache_trace where)
-{
-	bool success;
-	int ref;
-
-	success = __refcount_inc_not_zero(&cache->ref, &ref);
-	if (success)
-		trace_fscache_cache(cache->debug_id, ref + 1, where);
-	return success;
-}
-
-/*
- * Look up a cache cookie.
- */
-struct fscache_cache *fscache_lookup_cache(const char *name, bool is_cache)
-{
-	struct fscache_cache *candidate, *cache, *unnamed = NULL;
-
-	/* firstly check for the existence of the cache under read lock */
-	down_read(&fscache_addremove_sem);
-
-	list_for_each_entry(cache, &fscache_caches, cache_link) {
-		if (cache->name && name && strcmp(cache->name, name) == 0 &&
-		    fscache_get_cache_maybe(cache, fscache_cache_get_acquire))
-			goto got_cache_r;
-		if (!cache->name && !name &&
-		    fscache_get_cache_maybe(cache, fscache_cache_get_acquire))
-			goto got_cache_r;
-	}
-
-	if (!name) {
-		list_for_each_entry(cache, &fscache_caches, cache_link) {
-			if (cache->name &&
-			    fscache_get_cache_maybe(cache, fscache_cache_get_acquire))
-				goto got_cache_r;
-		}
-	}
-
-	up_read(&fscache_addremove_sem);
-
-	/* the cache does not exist - create a candidate */
-	candidate = fscache_alloc_cache(name);
-	if (!candidate)
-		return ERR_PTR(-ENOMEM);
-
-	/* write lock, search again and add if still not present */
-	down_write(&fscache_addremove_sem);
-
-	list_for_each_entry(cache, &fscache_caches, cache_link) {
-		if (cache->name && name && strcmp(cache->name, name) == 0 &&
-		    fscache_get_cache_maybe(cache, fscache_cache_get_acquire))
-			goto got_cache_w;
-		if (!cache->name) {
-			unnamed = cache;
-			if (!name &&
-			    fscache_get_cache_maybe(cache, fscache_cache_get_acquire))
-				goto got_cache_w;
-		}
-	}
-
-	if (unnamed && is_cache &&
-	    fscache_get_cache_maybe(unnamed, fscache_cache_get_acquire))
-		goto use_unnamed_cache;
-
-	if (!name) {
-		list_for_each_entry(cache, &fscache_caches, cache_link) {
-			if (cache->name &&
-			    fscache_get_cache_maybe(cache, fscache_cache_get_acquire))
-				goto got_cache_w;
-		}
-	}
-
-	list_add_tail(&candidate->cache_link, &fscache_caches);
-	trace_fscache_cache(candidate->debug_id,
-			    refcount_read(&candidate->ref),
-			    fscache_cache_new_acquire);
-	up_write(&fscache_addremove_sem);
-	return candidate;
-
-got_cache_r:
-	up_read(&fscache_addremove_sem);
-	return cache;
-use_unnamed_cache:
-	cache = unnamed;
-	cache->name = candidate->name;
-	candidate->name = NULL;
-got_cache_w:
-	up_write(&fscache_addremove_sem);
-	kfree(candidate->name);
-	kfree(candidate);
-	return cache;
-}
-
-/**
- * fscache_acquire_cache - Acquire a cache-level cookie.
- * @name: The name of the cache.
- *
- * Get a cookie to represent an actual cache.  If a name is given and there is
- * a nameless cache record available, this will acquire that and set its name,
- * directing all the volumes using it to this cache.
- *
- * The cache will be switched over to the preparing state if not currently in
- * use, otherwise -EBUSY will be returned.
- */
-struct fscache_cache *fscache_acquire_cache(const char *name)
-{
-	struct fscache_cache *cache;
-
-	ASSERT(name);
-	cache = fscache_lookup_cache(name, true);
-	if (IS_ERR(cache))
-		return cache;
-
-	if (!fscache_set_cache_state_maybe(cache,
-					   FSCACHE_CACHE_IS_NOT_PRESENT,
-					   FSCACHE_CACHE_IS_PREPARING)) {
-		pr_warn("Cache tag %s in use\n", name);
-		fscache_put_cache(cache, fscache_cache_put_cache);
-		return ERR_PTR(-EBUSY);
-	}
-
-	return cache;
-}
-EXPORT_SYMBOL(fscache_acquire_cache);
-
-/**
- * fscache_put_cache - Release a cache-level cookie.
- * @cache: The cache cookie to be released
- * @where: An indication of where the release happened
- *
- * Release the caller's reference on a cache-level cookie.  The @where
- * indication should give information about the circumstances in which the call
- * occurs and will be logged through a tracepoint.
- */
-void fscache_put_cache(struct fscache_cache *cache,
-		       enum fscache_cache_trace where)
-{
-	unsigned int debug_id;
-	bool zero;
-	int ref;
-
-	if (IS_ERR_OR_NULL(cache))
-		return;
-
-	debug_id = cache->debug_id;
-	zero = __refcount_dec_and_test(&cache->ref, &ref);
-	trace_fscache_cache(debug_id, ref - 1, where);
-
-	if (zero) {
-		down_write(&fscache_addremove_sem);
-		list_del_init(&cache->cache_link);
-		up_write(&fscache_addremove_sem);
-		kfree(cache->name);
-		kfree(cache);
-	}
-}
-
-/**
- * fscache_relinquish_cache - Reset cache state and release cookie
- * @cache: The cache cookie to be released
- *
- * Reset the state of a cache and release the caller's reference on a cache
- * cookie.
- */
-void fscache_relinquish_cache(struct fscache_cache *cache)
-{
-	enum fscache_cache_trace where =
-		(cache->state == FSCACHE_CACHE_IS_PREPARING) ?
-		fscache_cache_put_prep_failed :
-		fscache_cache_put_relinquish;
-
-	cache->ops = NULL;
-	cache->cache_priv = NULL;
-	fscache_set_cache_state(cache, FSCACHE_CACHE_IS_NOT_PRESENT);
-	fscache_put_cache(cache, where);
-}
-EXPORT_SYMBOL(fscache_relinquish_cache);
-
-/**
- * fscache_add_cache - Declare a cache as being open for business
- * @cache: The cache-level cookie representing the cache
- * @ops: Table of cache operations to use
- * @cache_priv: Private data for the cache record
- *
- * 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,
-		      const struct fscache_cache_ops *ops,
-		      void *cache_priv)
-{
-	int n_accesses;
-
-	_enter("{%s,%s}", ops->name, cache->name);
-
-	BUG_ON(fscache_cache_state(cache) != FSCACHE_CACHE_IS_PREPARING);
-
-	/* Get a ref on the cache cookie and keep its n_accesses counter raised
-	 * by 1 to prevent wakeups from transitioning it to 0 until we're
-	 * withdrawing caching services from it.
-	 */
-	n_accesses = atomic_inc_return(&cache->n_accesses);
-	trace_fscache_access_cache(cache->debug_id, refcount_read(&cache->ref),
-				   n_accesses, fscache_access_cache_pin);
-
-	down_write(&fscache_addremove_sem);
-
-	cache->ops = ops;
-	cache->cache_priv = cache_priv;
-	fscache_set_cache_state(cache, FSCACHE_CACHE_IS_ACTIVE);
-
-	up_write(&fscache_addremove_sem);
-	pr_notice("Cache \"%s\" added (type %s)\n", cache->name, ops->name);
-	_leave(" = 0 [%s]", cache->name);
-	return 0;
-}
-EXPORT_SYMBOL(fscache_add_cache);
-
-/**
- * fscache_begin_cache_access - Pin a cache so it can be accessed
- * @cache: The cache-level cookie
- * @why: An indication of the circumstances of the access for tracing
- *
- * Attempt to pin the cache to prevent it from going away whilst we're
- * accessing it and returns true if successful.  This works as follows:
- *
- *  (1) If the cache tests as not live (state is not FSCACHE_CACHE_IS_ACTIVE),
- *      then we return false to indicate access was not permitted.
- *
- *  (2) If the cache tests as live, then we increment the n_accesses count and
- *      then recheck the liveness, ending the access if it ceased to be live.
- *
- *  (3) When we end the access, we decrement n_accesses and wake up the any
- *      waiters if it reaches 0.
- *
- *  (4) Whilst the cache is caching, n_accesses is kept artificially
- *      incremented to prevent wakeups from happening.
- *
- *  (5) When the cache is taken offline, the state is changed to prevent new
- *      accesses, n_accesses is decremented and we wait for n_accesses to
- *      become 0.
- */
-bool fscache_begin_cache_access(struct fscache_cache *cache, enum fscache_access_trace why)
-{
-	int n_accesses;
-
-	if (!fscache_cache_is_live(cache))
-		return false;
-
-	n_accesses = atomic_inc_return(&cache->n_accesses);
-	smp_mb__after_atomic(); /* Reread live flag after n_accesses */
-	trace_fscache_access_cache(cache->debug_id, refcount_read(&cache->ref),
-				   n_accesses, why);
-	if (!fscache_cache_is_live(cache)) {
-		fscache_end_cache_access(cache, fscache_access_unlive);
-		return false;
-	}
-	return true;
-}
-
-/**
- * fscache_end_cache_access - Unpin a cache at the end of an access.
- * @cache: The cache-level cookie
- * @why: An indication of the circumstances of the access for tracing
- *
- * Unpin a cache after we've accessed it.  The @why indicator is merely
- * provided for tracing purposes.
- */
-void fscache_end_cache_access(struct fscache_cache *cache, enum fscache_access_trace why)
-{
-	int n_accesses;
-
-	smp_mb__before_atomic();
-	n_accesses = atomic_dec_return(&cache->n_accesses);
-	trace_fscache_access_cache(cache->debug_id, refcount_read(&cache->ref),
-				   n_accesses, why);
-	if (n_accesses == 0)
-		wake_up_var(&cache->n_accesses);
-}
-
-/**
- * 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 (fscache_set_cache_state_maybe(cache,
-					  FSCACHE_CACHE_IS_ACTIVE,
-					  FSCACHE_CACHE_GOT_IOERROR))
-		pr_err("Cache '%s' stopped due to I/O error\n",
-		       cache->name);
-}
-EXPORT_SYMBOL(fscache_io_error);
-
-/**
- * fscache_withdraw_cache - Withdraw a cache from the active service
- * @cache: The cache cookie
- *
- * Begin the process of withdrawing a cache from service.  This stops new
- * cache-level and volume-level accesses from taking place and waits for
- * currently ongoing cache-level accesses to end.
- */
-void fscache_withdraw_cache(struct fscache_cache *cache)
-{
-	int n_accesses;
-
-	pr_notice("Withdrawing cache \"%s\" (%u objs)\n",
-		  cache->name, atomic_read(&cache->object_count));
-
-	fscache_set_cache_state(cache, FSCACHE_CACHE_IS_WITHDRAWN);
-
-	/* Allow wakeups on dec-to-0 */
-	n_accesses = atomic_dec_return(&cache->n_accesses);
-	trace_fscache_access_cache(cache->debug_id, refcount_read(&cache->ref),
-				   n_accesses, fscache_access_cache_unpin);
-
-	wait_var_event(&cache->n_accesses,
-		       atomic_read(&cache->n_accesses) == 0);
-}
-EXPORT_SYMBOL(fscache_withdraw_cache);
-
-#ifdef CONFIG_PROC_FS
-static const char fscache_cache_states[NR__FSCACHE_CACHE_STATE] = "-PAEW";
-
-/*
- * Generate a list of caches in /proc/fs/fscache/caches
- */
-static int fscache_caches_seq_show(struct seq_file *m, void *v)
-{
-	struct fscache_cache *cache;
-
-	if (v == &fscache_caches) {
-		seq_puts(m,
-			 "CACHE    REF   VOLS  OBJS  ACCES S NAME\n"
-			 "======== ===== ===== ===== ===== = ===============\n"
-			 );
-		return 0;
-	}
-
-	cache = list_entry(v, struct fscache_cache, cache_link);
-	seq_printf(m,
-		   "%08x %5d %5d %5d %5d %c %s\n",
-		   cache->debug_id,
-		   refcount_read(&cache->ref),
-		   atomic_read(&cache->n_volumes),
-		   atomic_read(&cache->object_count),
-		   atomic_read(&cache->n_accesses),
-		   fscache_cache_states[cache->state],
-		   cache->name ?: "-");
-	return 0;
-}
-
-static void *fscache_caches_seq_start(struct seq_file *m, loff_t *_pos)
-	__acquires(fscache_addremove_sem)
-{
-	down_read(&fscache_addremove_sem);
-	return seq_list_start_head(&fscache_caches, *_pos);
-}
-
-static void *fscache_caches_seq_next(struct seq_file *m, void *v, loff_t *_pos)
-{
-	return seq_list_next(v, &fscache_caches, _pos);
-}
-
-static void fscache_caches_seq_stop(struct seq_file *m, void *v)
-	__releases(fscache_addremove_sem)
-{
-	up_read(&fscache_addremove_sem);
-}
-
-const struct seq_operations fscache_caches_seq_ops = {
-	.start  = fscache_caches_seq_start,
-	.next   = fscache_caches_seq_next,
-	.stop   = fscache_caches_seq_stop,
-	.show   = fscache_caches_seq_show,
-};
-#endif /* CONFIG_PROC_FS */
diff --git a/fs/fscache/cookie.c b/fs/fscache/cookie.c
deleted file mode 100644
index bce2492186..0000000000
--- a/fs/fscache/cookie.c
+++ /dev/null
@@ -1,1180 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* netfs cookie management
- *
- * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- *
- * See Documentation/filesystems/caching/netfs-api.rst for more information on
- * the netfs API.
- */
-
-#define FSCACHE_DEBUG_LEVEL COOKIE
-#include <linux/module.h>
-#include <linux/slab.h>
-#include "internal.h"
-
-struct kmem_cache *fscache_cookie_jar;
-
-static void fscache_cookie_lru_timed_out(struct timer_list *timer);
-static void fscache_cookie_lru_worker(struct work_struct *work);
-static void fscache_cookie_worker(struct work_struct *work);
-static void fscache_unhash_cookie(struct fscache_cookie *cookie);
-static void fscache_perform_invalidation(struct fscache_cookie *cookie);
-
-#define fscache_cookie_hash_shift 15
-static struct hlist_bl_head fscache_cookie_hash[1 << fscache_cookie_hash_shift];
-static LIST_HEAD(fscache_cookies);
-static DEFINE_RWLOCK(fscache_cookies_lock);
-static LIST_HEAD(fscache_cookie_lru);
-static DEFINE_SPINLOCK(fscache_cookie_lru_lock);
-DEFINE_TIMER(fscache_cookie_lru_timer, fscache_cookie_lru_timed_out);
-static DECLARE_WORK(fscache_cookie_lru_work, fscache_cookie_lru_worker);
-static const char fscache_cookie_states[FSCACHE_COOKIE_STATE__NR] = "-LCAIFUWRD";
-static unsigned int fscache_lru_cookie_timeout = 10 * HZ;
-
-void fscache_print_cookie(struct fscache_cookie *cookie, char prefix)
-{
-	const u8 *k;
-
-	pr_err("%c-cookie c=%08x [fl=%lx na=%u nA=%u s=%c]\n",
-	       prefix,
-	       cookie->debug_id,
-	       cookie->flags,
-	       atomic_read(&cookie->n_active),
-	       atomic_read(&cookie->n_accesses),
-	       fscache_cookie_states[cookie->state]);
-	pr_err("%c-cookie V=%08x [%s]\n",
-	       prefix,
-	       cookie->volume->debug_id,
-	       cookie->volume->key);
-
-	k = (cookie->key_len <= sizeof(cookie->inline_key)) ?
-		cookie->inline_key : cookie->key;
-	pr_err("%c-key=[%u] '%*phN'\n", prefix, cookie->key_len, cookie->key_len, k);
-}
-
-static void fscache_free_cookie(struct fscache_cookie *cookie)
-{
-	if (WARN_ON_ONCE(!list_empty(&cookie->commit_link))) {
-		spin_lock(&fscache_cookie_lru_lock);
-		list_del_init(&cookie->commit_link);
-		spin_unlock(&fscache_cookie_lru_lock);
-		fscache_stat_d(&fscache_n_cookies_lru);
-		fscache_stat(&fscache_n_cookies_lru_removed);
-	}
-
-	if (WARN_ON_ONCE(test_bit(FSCACHE_COOKIE_IS_HASHED, &cookie->flags))) {
-		fscache_print_cookie(cookie, 'F');
-		return;
-	}
-
-	write_lock(&fscache_cookies_lock);
-	list_del(&cookie->proc_link);
-	write_unlock(&fscache_cookies_lock);
-	if (cookie->aux_len > sizeof(cookie->inline_aux))
-		kfree(cookie->aux);
-	if (cookie->key_len > sizeof(cookie->inline_key))
-		kfree(cookie->key);
-	fscache_stat_d(&fscache_n_cookies);
-	kmem_cache_free(fscache_cookie_jar, cookie);
-}
-
-static void __fscache_queue_cookie(struct fscache_cookie *cookie)
-{
-	if (!queue_work(fscache_wq, &cookie->work))
-		fscache_put_cookie(cookie, fscache_cookie_put_over_queued);
-}
-
-static void fscache_queue_cookie(struct fscache_cookie *cookie,
-				 enum fscache_cookie_trace where)
-{
-	fscache_get_cookie(cookie, where);
-	__fscache_queue_cookie(cookie);
-}
-
-/*
- * Initialise the access gate on a cookie by setting a flag to prevent the
- * state machine from being queued when the access counter transitions to 0.
- * We're only interested in this when we withdraw caching services from the
- * cookie.
- */
-static void fscache_init_access_gate(struct fscache_cookie *cookie)
-{
-	int n_accesses;
-
-	n_accesses = atomic_read(&cookie->n_accesses);
-	trace_fscache_access(cookie->debug_id, refcount_read(&cookie->ref),
-			     n_accesses, fscache_access_cache_pin);
-	set_bit(FSCACHE_COOKIE_NO_ACCESS_WAKE, &cookie->flags);
-}
-
-/**
- * fscache_end_cookie_access - Unpin a cache at the end of an access.
- * @cookie: A data file cookie
- * @why: An indication of the circumstances of the access for tracing
- *
- * Unpin a cache cookie after we've accessed it and bring a deferred
- * relinquishment or withdrawal state into effect.
- *
- * The @why indicator is provided for tracing purposes.
- */
-void fscache_end_cookie_access(struct fscache_cookie *cookie,
-			       enum fscache_access_trace why)
-{
-	int n_accesses;
-
-	smp_mb__before_atomic();
-	n_accesses = atomic_dec_return(&cookie->n_accesses);
-	trace_fscache_access(cookie->debug_id, refcount_read(&cookie->ref),
-			     n_accesses, why);
-	if (n_accesses == 0 &&
-	    !test_bit(FSCACHE_COOKIE_NO_ACCESS_WAKE, &cookie->flags))
-		fscache_queue_cookie(cookie, fscache_cookie_get_end_access);
-}
-EXPORT_SYMBOL(fscache_end_cookie_access);
-
-/*
- * Pin the cache behind a cookie so that we can access it.
- */
-static void __fscache_begin_cookie_access(struct fscache_cookie *cookie,
-					  enum fscache_access_trace why)
-{
-	int n_accesses;
-
-	n_accesses = atomic_inc_return(&cookie->n_accesses);
-	smp_mb__after_atomic(); /* (Future) read state after is-caching.
-				 * Reread n_accesses after is-caching
-				 */
-	trace_fscache_access(cookie->debug_id, refcount_read(&cookie->ref),
-			     n_accesses, why);
-}
-
-/**
- * fscache_begin_cookie_access - Pin a cache so data can be accessed
- * @cookie: A data file cookie
- * @why: An indication of the circumstances of the access for tracing
- *
- * Attempt to pin the cache to prevent it from going away whilst we're
- * accessing data and returns true if successful.  This works as follows:
- *
- *  (1) If the cookie is not being cached (ie. FSCACHE_COOKIE_IS_CACHING is not
- *      set), we return false to indicate access was not permitted.
- *
- *  (2) If the cookie is being cached, we increment its n_accesses count and
- *      then recheck the IS_CACHING flag, ending the access if it got cleared.
- *
- *  (3) When we end the access, we decrement the cookie's n_accesses and wake
- *      up the any waiters if it reaches 0.
- *
- *  (4) Whilst the cookie is actively being cached, its n_accesses is kept
- *      artificially incremented to prevent wakeups from happening.
- *
- *  (5) When the cache is taken offline or if the cookie is culled, the flag is
- *      cleared to prevent new accesses, the cookie's n_accesses is decremented
- *      and we wait for it to become 0.
- *
- * The @why indicator are merely provided for tracing purposes.
- */
-bool fscache_begin_cookie_access(struct fscache_cookie *cookie,
-				 enum fscache_access_trace why)
-{
-	if (!test_bit(FSCACHE_COOKIE_IS_CACHING, &cookie->flags))
-		return false;
-	__fscache_begin_cookie_access(cookie, why);
-	if (!test_bit(FSCACHE_COOKIE_IS_CACHING, &cookie->flags) ||
-	    !fscache_cache_is_live(cookie->volume->cache)) {
-		fscache_end_cookie_access(cookie, fscache_access_unlive);
-		return false;
-	}
-	return true;
-}
-
-static inline void wake_up_cookie_state(struct fscache_cookie *cookie)
-{
-	/* Use a barrier to ensure that waiters see the state variable
-	 * change, as spin_unlock doesn't guarantee a barrier.
-	 *
-	 * See comments over wake_up_bit() and waitqueue_active().
-	 */
-	smp_mb();
-	wake_up_var(&cookie->state);
-}
-
-/*
- * Change the state a cookie is at and wake up anyone waiting for that.  Impose
- * an ordering between the stuff stored in the cookie and the state member.
- * Paired with fscache_cookie_state().
- */
-static void __fscache_set_cookie_state(struct fscache_cookie *cookie,
-				       enum fscache_cookie_state state)
-{
-	smp_store_release(&cookie->state, state);
-}
-
-static void fscache_set_cookie_state(struct fscache_cookie *cookie,
-				     enum fscache_cookie_state state)
-{
-	spin_lock(&cookie->lock);
-	__fscache_set_cookie_state(cookie, state);
-	spin_unlock(&cookie->lock);
-	wake_up_cookie_state(cookie);
-}
-
-/**
- * fscache_cookie_lookup_negative - Note negative lookup
- * @cookie: The cookie that was being looked up
- *
- * Note that some part of the metadata path in the cache doesn't exist and so
- * we can release any waiting readers in the certain knowledge that there's
- * nothing for them to actually read.
- *
- * This function uses no locking and must only be called from the state machine.
- */
-void fscache_cookie_lookup_negative(struct fscache_cookie *cookie)
-{
-	set_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags);
-	fscache_set_cookie_state(cookie, FSCACHE_COOKIE_STATE_CREATING);
-}
-EXPORT_SYMBOL(fscache_cookie_lookup_negative);
-
-/**
- * fscache_resume_after_invalidation - Allow I/O to resume after invalidation
- * @cookie: The cookie that was invalidated
- *
- * Tell fscache that invalidation is sufficiently complete that I/O can be
- * allowed again.
- */
-void fscache_resume_after_invalidation(struct fscache_cookie *cookie)
-{
-	fscache_set_cookie_state(cookie, FSCACHE_COOKIE_STATE_ACTIVE);
-}
-EXPORT_SYMBOL(fscache_resume_after_invalidation);
-
-/**
- * fscache_caching_failed - Report that a failure stopped caching on a cookie
- * @cookie: The cookie that was affected
- *
- * Tell fscache that caching on a cookie needs to be stopped due to some sort
- * of failure.
- *
- * This function uses no locking and must only be called from the state machine.
- */
-void fscache_caching_failed(struct fscache_cookie *cookie)
-{
-	clear_bit(FSCACHE_COOKIE_IS_CACHING, &cookie->flags);
-	fscache_set_cookie_state(cookie, FSCACHE_COOKIE_STATE_FAILED);
-	trace_fscache_cookie(cookie->debug_id, refcount_read(&cookie->ref),
-				fscache_cookie_failed);
-}
-EXPORT_SYMBOL(fscache_caching_failed);
-
-/*
- * Set the index key in a cookie.  The cookie struct has space for a 16-byte
- * key plus length and hash, but if that's not big enough, it's instead a
- * pointer to a buffer containing 3 bytes of hash, 1 byte of length and then
- * the key data.
- */
-static int fscache_set_key(struct fscache_cookie *cookie,
-			   const void *index_key, size_t index_key_len)
-{
-	void *buf;
-	size_t buf_size;
-
-	buf_size = round_up(index_key_len, sizeof(__le32));
-
-	if (index_key_len > sizeof(cookie->inline_key)) {
-		buf = kzalloc(buf_size, GFP_KERNEL);
-		if (!buf)
-			return -ENOMEM;
-		cookie->key = buf;
-	} else {
-		buf = cookie->inline_key;
-	}
-
-	memcpy(buf, index_key, index_key_len);
-	cookie->key_hash = fscache_hash(cookie->volume->key_hash,
-					buf, buf_size);
-	return 0;
-}
-
-static bool fscache_cookie_same(const struct fscache_cookie *a,
-				const struct fscache_cookie *b)
-{
-	const void *ka, *kb;
-
-	if (a->key_hash	!= b->key_hash ||
-	    a->volume	!= b->volume ||
-	    a->key_len	!= b->key_len)
-		return false;
-
-	if (a->key_len <= sizeof(a->inline_key)) {
-		ka = &a->inline_key;
-		kb = &b->inline_key;
-	} else {
-		ka = a->key;
-		kb = b->key;
-	}
-	return memcmp(ka, kb, a->key_len) == 0;
-}
-
-static atomic_t fscache_cookie_debug_id = ATOMIC_INIT(1);
-
-/*
- * Allocate a cookie.
- */
-static struct fscache_cookie *fscache_alloc_cookie(
-	struct fscache_volume *volume,
-	u8 advice,
-	const void *index_key, size_t index_key_len,
-	const void *aux_data, size_t aux_data_len,
-	loff_t object_size)
-{
-	struct fscache_cookie *cookie;
-
-	/* allocate and initialise a cookie */
-	cookie = kmem_cache_zalloc(fscache_cookie_jar, GFP_KERNEL);
-	if (!cookie)
-		return NULL;
-	fscache_stat(&fscache_n_cookies);
-
-	cookie->volume		= volume;
-	cookie->advice		= advice;
-	cookie->key_len		= index_key_len;
-	cookie->aux_len		= aux_data_len;
-	cookie->object_size	= object_size;
-	if (object_size == 0)
-		__set_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags);
-
-	if (fscache_set_key(cookie, index_key, index_key_len) < 0)
-		goto nomem;
-
-	if (cookie->aux_len <= sizeof(cookie->inline_aux)) {
-		memcpy(cookie->inline_aux, aux_data, cookie->aux_len);
-	} else {
-		cookie->aux = kmemdup(aux_data, cookie->aux_len, GFP_KERNEL);
-		if (!cookie->aux)
-			goto nomem;
-	}
-
-	refcount_set(&cookie->ref, 1);
-	cookie->debug_id = atomic_inc_return(&fscache_cookie_debug_id);
-	spin_lock_init(&cookie->lock);
-	INIT_LIST_HEAD(&cookie->commit_link);
-	INIT_WORK(&cookie->work, fscache_cookie_worker);
-	__fscache_set_cookie_state(cookie, FSCACHE_COOKIE_STATE_QUIESCENT);
-
-	write_lock(&fscache_cookies_lock);
-	list_add_tail(&cookie->proc_link, &fscache_cookies);
-	write_unlock(&fscache_cookies_lock);
-	fscache_see_cookie(cookie, fscache_cookie_new_acquire);
-	return cookie;
-
-nomem:
-	fscache_free_cookie(cookie);
-	return NULL;
-}
-
-static inline bool fscache_cookie_is_dropped(struct fscache_cookie *cookie)
-{
-	return READ_ONCE(cookie->state) == FSCACHE_COOKIE_STATE_DROPPED;
-}
-
-static void fscache_wait_on_collision(struct fscache_cookie *candidate,
-				      struct fscache_cookie *wait_for)
-{
-	enum fscache_cookie_state *statep = &wait_for->state;
-
-	wait_var_event_timeout(statep, fscache_cookie_is_dropped(wait_for),
-			       20 * HZ);
-	if (!fscache_cookie_is_dropped(wait_for)) {
-		pr_notice("Potential collision c=%08x old: c=%08x",
-			  candidate->debug_id, wait_for->debug_id);
-		wait_var_event(statep, fscache_cookie_is_dropped(wait_for));
-	}
-}
-
-/*
- * Attempt to insert the new cookie into the hash.  If there's a collision, we
- * wait for the old cookie to complete if it's being relinquished and an error
- * otherwise.
- */
-static bool fscache_hash_cookie(struct fscache_cookie *candidate)
-{
-	struct fscache_cookie *cursor, *wait_for = NULL;
-	struct hlist_bl_head *h;
-	struct hlist_bl_node *p;
-	unsigned int bucket;
-
-	bucket = candidate->key_hash & (ARRAY_SIZE(fscache_cookie_hash) - 1);
-	h = &fscache_cookie_hash[bucket];
-
-	hlist_bl_lock(h);
-	hlist_bl_for_each_entry(cursor, p, h, hash_link) {
-		if (fscache_cookie_same(candidate, cursor)) {
-			if (!test_bit(FSCACHE_COOKIE_RELINQUISHED, &cursor->flags))
-				goto collision;
-			wait_for = fscache_get_cookie(cursor,
-						      fscache_cookie_get_hash_collision);
-			break;
-		}
-	}
-
-	fscache_get_volume(candidate->volume, fscache_volume_get_cookie);
-	atomic_inc(&candidate->volume->n_cookies);
-	hlist_bl_add_head(&candidate->hash_link, h);
-	set_bit(FSCACHE_COOKIE_IS_HASHED, &candidate->flags);
-	hlist_bl_unlock(h);
-
-	if (wait_for) {
-		fscache_wait_on_collision(candidate, wait_for);
-		fscache_put_cookie(wait_for, fscache_cookie_put_hash_collision);
-	}
-	return true;
-
-collision:
-	trace_fscache_cookie(cursor->debug_id, refcount_read(&cursor->ref),
-			     fscache_cookie_collision);
-	pr_err("Duplicate cookie detected\n");
-	fscache_print_cookie(cursor, 'O');
-	fscache_print_cookie(candidate, 'N');
-	hlist_bl_unlock(h);
-	return false;
-}
-
-/*
- * Request a cookie to represent a data storage object within a volume.
- *
- * We never let on to the netfs about errors.  We may set a negative cookie
- * pointer, but that's okay
- */
-struct fscache_cookie *__fscache_acquire_cookie(
-	struct fscache_volume *volume,
-	u8 advice,
-	const void *index_key, size_t index_key_len,
-	const void *aux_data, size_t aux_data_len,
-	loff_t object_size)
-{
-	struct fscache_cookie *cookie;
-
-	_enter("V=%x", volume->debug_id);
-
-	if (!index_key || !index_key_len || index_key_len > 255 || aux_data_len > 255)
-		return NULL;
-	if (!aux_data || !aux_data_len) {
-		aux_data = NULL;
-		aux_data_len = 0;
-	}
-
-	fscache_stat(&fscache_n_acquires);
-
-	cookie = fscache_alloc_cookie(volume, advice,
-				      index_key, index_key_len,
-				      aux_data, aux_data_len,
-				      object_size);
-	if (!cookie) {
-		fscache_stat(&fscache_n_acquires_oom);
-		return NULL;
-	}
-
-	if (!fscache_hash_cookie(cookie)) {
-		fscache_see_cookie(cookie, fscache_cookie_discard);
-		fscache_free_cookie(cookie);
-		return NULL;
-	}
-
-	trace_fscache_acquire(cookie);
-	fscache_stat(&fscache_n_acquires_ok);
-	_leave(" = c=%08x", cookie->debug_id);
-	return cookie;
-}
-EXPORT_SYMBOL(__fscache_acquire_cookie);
-
-/*
- * Prepare a cache object to be written to.
- */
-static void fscache_prepare_to_write(struct fscache_cookie *cookie)
-{
-	cookie->volume->cache->ops->prepare_to_write(cookie);
-}
-
-/*
- * Look up a cookie in the cache.
- */
-static void fscache_perform_lookup(struct fscache_cookie *cookie)
-{
-	enum fscache_access_trace trace = fscache_access_lookup_cookie_end_failed;
-	bool need_withdraw = false;
-
-	_enter("");
-
-	if (!cookie->volume->cache_priv) {
-		fscache_create_volume(cookie->volume, true);
-		if (!cookie->volume->cache_priv) {
-			fscache_set_cookie_state(cookie, FSCACHE_COOKIE_STATE_QUIESCENT);
-			goto out;
-		}
-	}
-
-	if (!cookie->volume->cache->ops->lookup_cookie(cookie)) {
-		if (cookie->state != FSCACHE_COOKIE_STATE_FAILED)
-			fscache_set_cookie_state(cookie, FSCACHE_COOKIE_STATE_QUIESCENT);
-		need_withdraw = true;
-		_leave(" [fail]");
-		goto out;
-	}
-
-	fscache_see_cookie(cookie, fscache_cookie_see_active);
-	spin_lock(&cookie->lock);
-	if (test_and_clear_bit(FSCACHE_COOKIE_DO_INVALIDATE, &cookie->flags))
-		__fscache_set_cookie_state(cookie,
-					   FSCACHE_COOKIE_STATE_INVALIDATING);
-	else
-		__fscache_set_cookie_state(cookie, FSCACHE_COOKIE_STATE_ACTIVE);
-	spin_unlock(&cookie->lock);
-	wake_up_cookie_state(cookie);
-	trace = fscache_access_lookup_cookie_end;
-
-out:
-	fscache_end_cookie_access(cookie, trace);
-	if (need_withdraw)
-		fscache_withdraw_cookie(cookie);
-	fscache_end_volume_access(cookie->volume, cookie, trace);
-}
-
-/*
- * Begin the process of looking up a cookie.  We offload the actual process to
- * a worker thread.
- */
-static bool fscache_begin_lookup(struct fscache_cookie *cookie, bool will_modify)
-{
-	if (will_modify) {
-		set_bit(FSCACHE_COOKIE_LOCAL_WRITE, &cookie->flags);
-		set_bit(FSCACHE_COOKIE_DO_PREP_TO_WRITE, &cookie->flags);
-	}
-	if (!fscache_begin_volume_access(cookie->volume, cookie,
-					 fscache_access_lookup_cookie))
-		return false;
-
-	__fscache_begin_cookie_access(cookie, fscache_access_lookup_cookie);
-	__fscache_set_cookie_state(cookie, FSCACHE_COOKIE_STATE_LOOKING_UP);
-	set_bit(FSCACHE_COOKIE_IS_CACHING, &cookie->flags);
-	set_bit(FSCACHE_COOKIE_HAS_BEEN_CACHED, &cookie->flags);
-	return true;
-}
-
-/*
- * Start using the cookie for I/O.  This prevents the backing object from being
- * reaped by VM pressure.
- */
-void __fscache_use_cookie(struct fscache_cookie *cookie, bool will_modify)
-{
-	enum fscache_cookie_state state;
-	bool queue = false;
-	int n_active;
-
-	_enter("c=%08x", cookie->debug_id);
-
-	if (WARN(test_bit(FSCACHE_COOKIE_RELINQUISHED, &cookie->flags),
-		 "Trying to use relinquished cookie\n"))
-		return;
-
-	spin_lock(&cookie->lock);
-
-	n_active = atomic_inc_return(&cookie->n_active);
-	trace_fscache_active(cookie->debug_id, refcount_read(&cookie->ref),
-			     n_active, atomic_read(&cookie->n_accesses),
-			     will_modify ?
-			     fscache_active_use_modify : fscache_active_use);
-
-again:
-	state = fscache_cookie_state(cookie);
-	switch (state) {
-	case FSCACHE_COOKIE_STATE_QUIESCENT:
-		queue = fscache_begin_lookup(cookie, will_modify);
-		break;
-
-	case FSCACHE_COOKIE_STATE_LOOKING_UP:
-	case FSCACHE_COOKIE_STATE_CREATING:
-		if (will_modify)
-			set_bit(FSCACHE_COOKIE_LOCAL_WRITE, &cookie->flags);
-		break;
-	case FSCACHE_COOKIE_STATE_ACTIVE:
-	case FSCACHE_COOKIE_STATE_INVALIDATING:
-		if (will_modify &&
-		    !test_and_set_bit(FSCACHE_COOKIE_LOCAL_WRITE, &cookie->flags)) {
-			set_bit(FSCACHE_COOKIE_DO_PREP_TO_WRITE, &cookie->flags);
-			queue = true;
-		}
-		/*
-		 * We could race with cookie_lru which may set LRU_DISCARD bit
-		 * but has yet to run the cookie state machine.  If this happens
-		 * and another thread tries to use the cookie, clear LRU_DISCARD
-		 * so we don't end up withdrawing the cookie while in use.
-		 */
-		if (test_and_clear_bit(FSCACHE_COOKIE_DO_LRU_DISCARD, &cookie->flags))
-			fscache_see_cookie(cookie, fscache_cookie_see_lru_discard_clear);
-		break;
-
-	case FSCACHE_COOKIE_STATE_FAILED:
-	case FSCACHE_COOKIE_STATE_WITHDRAWING:
-		break;
-
-	case FSCACHE_COOKIE_STATE_LRU_DISCARDING:
-		spin_unlock(&cookie->lock);
-		wait_var_event(&cookie->state,
-			       fscache_cookie_state(cookie) !=
-			       FSCACHE_COOKIE_STATE_LRU_DISCARDING);
-		spin_lock(&cookie->lock);
-		goto again;
-
-	case FSCACHE_COOKIE_STATE_DROPPED:
-	case FSCACHE_COOKIE_STATE_RELINQUISHING:
-		WARN(1, "Can't use cookie in state %u\n", state);
-		break;
-	}
-
-	spin_unlock(&cookie->lock);
-	if (queue)
-		fscache_queue_cookie(cookie, fscache_cookie_get_use_work);
-	_leave("");
-}
-EXPORT_SYMBOL(__fscache_use_cookie);
-
-static void fscache_unuse_cookie_locked(struct fscache_cookie *cookie)
-{
-	clear_bit(FSCACHE_COOKIE_DISABLED, &cookie->flags);
-	if (!test_bit(FSCACHE_COOKIE_IS_CACHING, &cookie->flags))
-		return;
-
-	cookie->unused_at = jiffies;
-	spin_lock(&fscache_cookie_lru_lock);
-	if (list_empty(&cookie->commit_link)) {
-		fscache_get_cookie(cookie, fscache_cookie_get_lru);
-		fscache_stat(&fscache_n_cookies_lru);
-	}
-	list_move_tail(&cookie->commit_link, &fscache_cookie_lru);
-
-	spin_unlock(&fscache_cookie_lru_lock);
-	timer_reduce(&fscache_cookie_lru_timer,
-		     jiffies + fscache_lru_cookie_timeout);
-}
-
-/*
- * Stop using the cookie for I/O.
- */
-void __fscache_unuse_cookie(struct fscache_cookie *cookie,
-			    const void *aux_data, const loff_t *object_size)
-{
-	unsigned int debug_id = cookie->debug_id;
-	unsigned int r = refcount_read(&cookie->ref);
-	unsigned int a = atomic_read(&cookie->n_accesses);
-	unsigned int c;
-
-	if (aux_data || object_size)
-		__fscache_update_cookie(cookie, aux_data, object_size);
-
-	/* Subtract 1 from counter unless that drops it to 0 (ie. it was 1) */
-	c = atomic_fetch_add_unless(&cookie->n_active, -1, 1);
-	if (c != 1) {
-		trace_fscache_active(debug_id, r, c - 1, a, fscache_active_unuse);
-		return;
-	}
-
-	spin_lock(&cookie->lock);
-	r = refcount_read(&cookie->ref);
-	a = atomic_read(&cookie->n_accesses);
-	c = atomic_dec_return(&cookie->n_active);
-	trace_fscache_active(debug_id, r, c, a, fscache_active_unuse);
-	if (c == 0)
-		fscache_unuse_cookie_locked(cookie);
-	spin_unlock(&cookie->lock);
-}
-EXPORT_SYMBOL(__fscache_unuse_cookie);
-
-/*
- * Perform work upon the cookie, such as committing its cache state,
- * relinquishing it or withdrawing the backing cache.  We're protected from the
- * cache going away under us as object withdrawal must come through this
- * non-reentrant work item.
- */
-static void fscache_cookie_state_machine(struct fscache_cookie *cookie)
-{
-	enum fscache_cookie_state state;
-	bool wake = false;
-
-	_enter("c=%x", cookie->debug_id);
-
-again:
-	spin_lock(&cookie->lock);
-again_locked:
-	state = cookie->state;
-	switch (state) {
-	case FSCACHE_COOKIE_STATE_QUIESCENT:
-		/* The QUIESCENT state is jumped to the LOOKING_UP state by
-		 * fscache_use_cookie().
-		 */
-
-		if (atomic_read(&cookie->n_accesses) == 0 &&
-		    test_bit(FSCACHE_COOKIE_DO_RELINQUISH, &cookie->flags)) {
-			__fscache_set_cookie_state(cookie,
-						   FSCACHE_COOKIE_STATE_RELINQUISHING);
-			wake = true;
-			goto again_locked;
-		}
-		break;
-
-	case FSCACHE_COOKIE_STATE_LOOKING_UP:
-		spin_unlock(&cookie->lock);
-		fscache_init_access_gate(cookie);
-		fscache_perform_lookup(cookie);
-		goto again;
-
-	case FSCACHE_COOKIE_STATE_INVALIDATING:
-		spin_unlock(&cookie->lock);
-		fscache_perform_invalidation(cookie);
-		goto again;
-
-	case FSCACHE_COOKIE_STATE_ACTIVE:
-		if (test_and_clear_bit(FSCACHE_COOKIE_DO_PREP_TO_WRITE, &cookie->flags)) {
-			spin_unlock(&cookie->lock);
-			fscache_prepare_to_write(cookie);
-			spin_lock(&cookie->lock);
-		}
-		if (test_bit(FSCACHE_COOKIE_DO_LRU_DISCARD, &cookie->flags)) {
-			__fscache_set_cookie_state(cookie,
-						   FSCACHE_COOKIE_STATE_LRU_DISCARDING);
-			wake = true;
-			goto again_locked;
-		}
-		fallthrough;
-
-	case FSCACHE_COOKIE_STATE_FAILED:
-		if (test_and_clear_bit(FSCACHE_COOKIE_DO_INVALIDATE, &cookie->flags))
-			fscache_end_cookie_access(cookie, fscache_access_invalidate_cookie_end);
-
-		if (atomic_read(&cookie->n_accesses) != 0)
-			break;
-		if (test_bit(FSCACHE_COOKIE_DO_RELINQUISH, &cookie->flags)) {
-			__fscache_set_cookie_state(cookie,
-						   FSCACHE_COOKIE_STATE_RELINQUISHING);
-			wake = true;
-			goto again_locked;
-		}
-		if (test_bit(FSCACHE_COOKIE_DO_WITHDRAW, &cookie->flags)) {
-			__fscache_set_cookie_state(cookie,
-						   FSCACHE_COOKIE_STATE_WITHDRAWING);
-			wake = true;
-			goto again_locked;
-		}
-		break;
-
-	case FSCACHE_COOKIE_STATE_LRU_DISCARDING:
-	case FSCACHE_COOKIE_STATE_RELINQUISHING:
-	case FSCACHE_COOKIE_STATE_WITHDRAWING:
-		if (cookie->cache_priv) {
-			spin_unlock(&cookie->lock);
-			cookie->volume->cache->ops->withdraw_cookie(cookie);
-			spin_lock(&cookie->lock);
-		}
-
-		if (test_and_clear_bit(FSCACHE_COOKIE_DO_INVALIDATE, &cookie->flags))
-			fscache_end_cookie_access(cookie, fscache_access_invalidate_cookie_end);
-
-		switch (state) {
-		case FSCACHE_COOKIE_STATE_RELINQUISHING:
-			fscache_see_cookie(cookie, fscache_cookie_see_relinquish);
-			fscache_unhash_cookie(cookie);
-			__fscache_set_cookie_state(cookie,
-						   FSCACHE_COOKIE_STATE_DROPPED);
-			wake = true;
-			goto out;
-		case FSCACHE_COOKIE_STATE_LRU_DISCARDING:
-			fscache_see_cookie(cookie, fscache_cookie_see_lru_discard);
-			break;
-		case FSCACHE_COOKIE_STATE_WITHDRAWING:
-			fscache_see_cookie(cookie, fscache_cookie_see_withdraw);
-			break;
-		default:
-			BUG();
-		}
-
-		clear_bit(FSCACHE_COOKIE_NEEDS_UPDATE, &cookie->flags);
-		clear_bit(FSCACHE_COOKIE_DO_WITHDRAW, &cookie->flags);
-		clear_bit(FSCACHE_COOKIE_DO_LRU_DISCARD, &cookie->flags);
-		clear_bit(FSCACHE_COOKIE_DO_PREP_TO_WRITE, &cookie->flags);
-		set_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags);
-		__fscache_set_cookie_state(cookie, FSCACHE_COOKIE_STATE_QUIESCENT);
-		wake = true;
-		goto again_locked;
-
-	case FSCACHE_COOKIE_STATE_DROPPED:
-		break;
-
-	default:
-		WARN_ONCE(1, "Cookie %x in unexpected state %u\n",
-			  cookie->debug_id, state);
-		break;
-	}
-
-out:
-	spin_unlock(&cookie->lock);
-	if (wake)
-		wake_up_cookie_state(cookie);
-	_leave("");
-}
-
-static void fscache_cookie_worker(struct work_struct *work)
-{
-	struct fscache_cookie *cookie = container_of(work, struct fscache_cookie, work);
-
-	fscache_see_cookie(cookie, fscache_cookie_see_work);
-	fscache_cookie_state_machine(cookie);
-	fscache_put_cookie(cookie, fscache_cookie_put_work);
-}
-
-/*
- * Wait for the object to become inactive.  The cookie's work item will be
- * scheduled when someone transitions n_accesses to 0 - but if someone's
- * already done that, schedule it anyway.
- */
-static void __fscache_withdraw_cookie(struct fscache_cookie *cookie)
-{
-	int n_accesses;
-	bool unpinned;
-
-	unpinned = test_and_clear_bit(FSCACHE_COOKIE_NO_ACCESS_WAKE, &cookie->flags);
-
-	/* Need to read the access count after unpinning */
-	n_accesses = atomic_read(&cookie->n_accesses);
-	if (unpinned)
-		trace_fscache_access(cookie->debug_id, refcount_read(&cookie->ref),
-				     n_accesses, fscache_access_cache_unpin);
-	if (n_accesses == 0)
-		fscache_queue_cookie(cookie, fscache_cookie_get_end_access);
-}
-
-static void fscache_cookie_lru_do_one(struct fscache_cookie *cookie)
-{
-	fscache_see_cookie(cookie, fscache_cookie_see_lru_do_one);
-
-	spin_lock(&cookie->lock);
-	if (cookie->state != FSCACHE_COOKIE_STATE_ACTIVE ||
-	    time_before(jiffies, cookie->unused_at + fscache_lru_cookie_timeout) ||
-	    atomic_read(&cookie->n_active) > 0) {
-		spin_unlock(&cookie->lock);
-		fscache_stat(&fscache_n_cookies_lru_removed);
-	} else {
-		set_bit(FSCACHE_COOKIE_DO_LRU_DISCARD, &cookie->flags);
-		spin_unlock(&cookie->lock);
-		fscache_stat(&fscache_n_cookies_lru_expired);
-		_debug("lru c=%x", cookie->debug_id);
-		__fscache_withdraw_cookie(cookie);
-	}
-
-	fscache_put_cookie(cookie, fscache_cookie_put_lru);
-}
-
-static void fscache_cookie_lru_worker(struct work_struct *work)
-{
-	struct fscache_cookie *cookie;
-	unsigned long unused_at;
-
-	spin_lock(&fscache_cookie_lru_lock);
-
-	while (!list_empty(&fscache_cookie_lru)) {
-		cookie = list_first_entry(&fscache_cookie_lru,
-					  struct fscache_cookie, commit_link);
-		unused_at = cookie->unused_at + fscache_lru_cookie_timeout;
-		if (time_before(jiffies, unused_at)) {
-			timer_reduce(&fscache_cookie_lru_timer, unused_at);
-			break;
-		}
-
-		list_del_init(&cookie->commit_link);
-		fscache_stat_d(&fscache_n_cookies_lru);
-		spin_unlock(&fscache_cookie_lru_lock);
-		fscache_cookie_lru_do_one(cookie);
-		spin_lock(&fscache_cookie_lru_lock);
-	}
-
-	spin_unlock(&fscache_cookie_lru_lock);
-}
-
-static void fscache_cookie_lru_timed_out(struct timer_list *timer)
-{
-	queue_work(fscache_wq, &fscache_cookie_lru_work);
-}
-
-static void fscache_cookie_drop_from_lru(struct fscache_cookie *cookie)
-{
-	bool need_put = false;
-
-	if (!list_empty(&cookie->commit_link)) {
-		spin_lock(&fscache_cookie_lru_lock);
-		if (!list_empty(&cookie->commit_link)) {
-			list_del_init(&cookie->commit_link);
-			fscache_stat_d(&fscache_n_cookies_lru);
-			fscache_stat(&fscache_n_cookies_lru_dropped);
-			need_put = true;
-		}
-		spin_unlock(&fscache_cookie_lru_lock);
-		if (need_put)
-			fscache_put_cookie(cookie, fscache_cookie_put_lru);
-	}
-}
-
-/*
- * Remove a cookie from the hash table.
- */
-static void fscache_unhash_cookie(struct fscache_cookie *cookie)
-{
-	struct hlist_bl_head *h;
-	unsigned int bucket;
-
-	bucket = cookie->key_hash & (ARRAY_SIZE(fscache_cookie_hash) - 1);
-	h = &fscache_cookie_hash[bucket];
-
-	hlist_bl_lock(h);
-	hlist_bl_del(&cookie->hash_link);
-	clear_bit(FSCACHE_COOKIE_IS_HASHED, &cookie->flags);
-	hlist_bl_unlock(h);
-	fscache_stat(&fscache_n_relinquishes_dropped);
-}
-
-static void fscache_drop_withdraw_cookie(struct fscache_cookie *cookie)
-{
-	fscache_cookie_drop_from_lru(cookie);
-	__fscache_withdraw_cookie(cookie);
-}
-
-/**
- * fscache_withdraw_cookie - Mark a cookie for withdrawal
- * @cookie: The cookie to be withdrawn.
- *
- * Allow the cache backend to withdraw the backing for a cookie for its own
- * reasons, even if that cookie is in active use.
- */
-void fscache_withdraw_cookie(struct fscache_cookie *cookie)
-{
-	set_bit(FSCACHE_COOKIE_DO_WITHDRAW, &cookie->flags);
-	fscache_drop_withdraw_cookie(cookie);
-}
-EXPORT_SYMBOL(fscache_withdraw_cookie);
-
-/*
- * Allow the netfs to release a cookie back to the cache.
- * - the object will be marked as recyclable on disk if retire is true
- */
-void __fscache_relinquish_cookie(struct fscache_cookie *cookie, bool retire)
-{
-	fscache_stat(&fscache_n_relinquishes);
-	if (retire)
-		fscache_stat(&fscache_n_relinquishes_retire);
-
-	_enter("c=%08x{%d},%d",
-	       cookie->debug_id, atomic_read(&cookie->n_active), retire);
-
-	if (WARN(test_and_set_bit(FSCACHE_COOKIE_RELINQUISHED, &cookie->flags),
-		 "Cookie c=%x already relinquished\n", cookie->debug_id))
-		return;
-
-	if (retire)
-		set_bit(FSCACHE_COOKIE_RETIRED, &cookie->flags);
-	trace_fscache_relinquish(cookie, retire);
-
-	ASSERTCMP(atomic_read(&cookie->n_active), ==, 0);
-	ASSERTCMP(atomic_read(&cookie->volume->n_cookies), >, 0);
-	atomic_dec(&cookie->volume->n_cookies);
-
-	if (test_bit(FSCACHE_COOKIE_HAS_BEEN_CACHED, &cookie->flags)) {
-		set_bit(FSCACHE_COOKIE_DO_RELINQUISH, &cookie->flags);
-		fscache_drop_withdraw_cookie(cookie);
-	} else {
-		fscache_set_cookie_state(cookie, FSCACHE_COOKIE_STATE_DROPPED);
-		fscache_unhash_cookie(cookie);
-	}
-	fscache_put_cookie(cookie, fscache_cookie_put_relinquish);
-}
-EXPORT_SYMBOL(__fscache_relinquish_cookie);
-
-/*
- * Drop a reference to a cookie.
- */
-void fscache_put_cookie(struct fscache_cookie *cookie,
-			enum fscache_cookie_trace where)
-{
-	struct fscache_volume *volume = cookie->volume;
-	unsigned int cookie_debug_id = cookie->debug_id;
-	bool zero;
-	int ref;
-
-	zero = __refcount_dec_and_test(&cookie->ref, &ref);
-	trace_fscache_cookie(cookie_debug_id, ref - 1, where);
-	if (zero) {
-		fscache_free_cookie(cookie);
-		fscache_put_volume(volume, fscache_volume_put_cookie);
-	}
-}
-EXPORT_SYMBOL(fscache_put_cookie);
-
-/*
- * Get a reference to a cookie.
- */
-struct fscache_cookie *fscache_get_cookie(struct fscache_cookie *cookie,
-					  enum fscache_cookie_trace where)
-{
-	int ref;
-
-	__refcount_inc(&cookie->ref, &ref);
-	trace_fscache_cookie(cookie->debug_id, ref + 1, where);
-	return cookie;
-}
-EXPORT_SYMBOL(fscache_get_cookie);
-
-/*
- * Ask the cache to effect invalidation of a cookie.
- */
-static void fscache_perform_invalidation(struct fscache_cookie *cookie)
-{
-	if (!cookie->volume->cache->ops->invalidate_cookie(cookie))
-		fscache_caching_failed(cookie);
-	fscache_end_cookie_access(cookie, fscache_access_invalidate_cookie_end);
-}
-
-/*
- * Invalidate an object.
- */
-void __fscache_invalidate(struct fscache_cookie *cookie,
-			  const void *aux_data, loff_t new_size,
-			  unsigned int flags)
-{
-	bool is_caching;
-
-	_enter("c=%x", cookie->debug_id);
-
-	fscache_stat(&fscache_n_invalidates);
-
-	if (WARN(test_bit(FSCACHE_COOKIE_RELINQUISHED, &cookie->flags),
-		 "Trying to invalidate relinquished cookie\n"))
-		return;
-
-	if ((flags & FSCACHE_INVAL_DIO_WRITE) &&
-	    test_and_set_bit(FSCACHE_COOKIE_DISABLED, &cookie->flags))
-		return;
-
-	spin_lock(&cookie->lock);
-	set_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags);
-	fscache_update_aux(cookie, aux_data, &new_size);
-	cookie->inval_counter++;
-	trace_fscache_invalidate(cookie, new_size);
-
-	switch (cookie->state) {
-	case FSCACHE_COOKIE_STATE_INVALIDATING: /* is_still_valid will catch it */
-	default:
-		spin_unlock(&cookie->lock);
-		_leave(" [no %u]", cookie->state);
-		return;
-
-	case FSCACHE_COOKIE_STATE_LOOKING_UP:
-		if (!test_and_set_bit(FSCACHE_COOKIE_DO_INVALIDATE, &cookie->flags))
-			__fscache_begin_cookie_access(cookie, fscache_access_invalidate_cookie);
-		fallthrough;
-	case FSCACHE_COOKIE_STATE_CREATING:
-		spin_unlock(&cookie->lock);
-		_leave(" [look %x]", cookie->inval_counter);
-		return;
-
-	case FSCACHE_COOKIE_STATE_ACTIVE:
-		is_caching = fscache_begin_cookie_access(
-			cookie, fscache_access_invalidate_cookie);
-		if (is_caching)
-			__fscache_set_cookie_state(cookie, FSCACHE_COOKIE_STATE_INVALIDATING);
-		spin_unlock(&cookie->lock);
-		wake_up_cookie_state(cookie);
-
-		if (is_caching)
-			fscache_queue_cookie(cookie, fscache_cookie_get_inval_work);
-		_leave(" [inv]");
-		return;
-	}
-}
-EXPORT_SYMBOL(__fscache_invalidate);
-
-#ifdef CONFIG_PROC_FS
-/*
- * Generate a list of extant cookies in /proc/fs/fscache/cookies
- */
-static int fscache_cookies_seq_show(struct seq_file *m, void *v)
-{
-	struct fscache_cookie *cookie;
-	unsigned int keylen = 0, auxlen = 0;
-	u8 *p;
-
-	if (v == &fscache_cookies) {
-		seq_puts(m,
-			 "COOKIE   VOLUME   REF ACT ACC S FL DEF             \n"
-			 "======== ======== === === === = == ================\n"
-			 );
-		return 0;
-	}
-
-	cookie = list_entry(v, struct fscache_cookie, proc_link);
-
-	seq_printf(m,
-		   "%08x %08x %3d %3d %3d %c %02lx",
-		   cookie->debug_id,
-		   cookie->volume->debug_id,
-		   refcount_read(&cookie->ref),
-		   atomic_read(&cookie->n_active),
-		   atomic_read(&cookie->n_accesses),
-		   fscache_cookie_states[cookie->state],
-		   cookie->flags);
-
-	keylen = cookie->key_len;
-	auxlen = cookie->aux_len;
-
-	if (keylen > 0 || auxlen > 0) {
-		seq_puts(m, " ");
-		p = keylen <= sizeof(cookie->inline_key) ?
-			cookie->inline_key : cookie->key;
-		for (; keylen > 0; keylen--)
-			seq_printf(m, "%02x", *p++);
-		if (auxlen > 0) {
-			seq_puts(m, ", ");
-			p = auxlen <= sizeof(cookie->inline_aux) ?
-				cookie->inline_aux : cookie->aux;
-			for (; auxlen > 0; auxlen--)
-				seq_printf(m, "%02x", *p++);
-		}
-	}
-
-	seq_puts(m, "\n");
-	return 0;
-}
-
-static void *fscache_cookies_seq_start(struct seq_file *m, loff_t *_pos)
-	__acquires(fscache_cookies_lock)
-{
-	read_lock(&fscache_cookies_lock);
-	return seq_list_start_head(&fscache_cookies, *_pos);
-}
-
-static void *fscache_cookies_seq_next(struct seq_file *m, void *v, loff_t *_pos)
-{
-	return seq_list_next(v, &fscache_cookies, _pos);
-}
-
-static void fscache_cookies_seq_stop(struct seq_file *m, void *v)
-	__releases(rcu)
-{
-	read_unlock(&fscache_cookies_lock);
-}
-
-
-const struct seq_operations fscache_cookies_seq_ops = {
-	.start  = fscache_cookies_seq_start,
-	.next   = fscache_cookies_seq_next,
-	.stop   = fscache_cookies_seq_stop,
-	.show   = fscache_cookies_seq_show,
-};
-#endif
diff --git a/fs/fscache/internal.h b/fs/fscache/internal.h
deleted file mode 100644
index 1336f517e9..0000000000
--- a/fs/fscache/internal.h
+++ /dev/null
@@ -1,277 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-/* Internal definitions for FS-Cache
- *
- * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#ifdef pr_fmt
-#undef pr_fmt
-#endif
-
-#define pr_fmt(fmt) "FS-Cache: " fmt
-
-#include <linux/slab.h>
-#include <linux/fscache-cache.h>
-#include <trace/events/fscache.h>
-#include <linux/sched.h>
-#include <linux/seq_file.h>
-
-/*
- * cache.c
- */
-#ifdef CONFIG_PROC_FS
-extern const struct seq_operations fscache_caches_seq_ops;
-#endif
-bool fscache_begin_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
-void fscache_end_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
-struct fscache_cache *fscache_lookup_cache(const char *name, bool is_cache);
-void fscache_put_cache(struct fscache_cache *cache, enum fscache_cache_trace where);
-
-static inline enum fscache_cache_state fscache_cache_state(const struct fscache_cache *cache)
-{
-	return smp_load_acquire(&cache->state);
-}
-
-static inline bool fscache_cache_is_live(const struct fscache_cache *cache)
-{
-	return fscache_cache_state(cache) == FSCACHE_CACHE_IS_ACTIVE;
-}
-
-static inline void fscache_set_cache_state(struct fscache_cache *cache,
-					   enum fscache_cache_state new_state)
-{
-	smp_store_release(&cache->state, new_state);
-
-}
-
-static inline bool fscache_set_cache_state_maybe(struct fscache_cache *cache,
-						 enum fscache_cache_state old_state,
-						 enum fscache_cache_state new_state)
-{
-	return try_cmpxchg_release(&cache->state, &old_state, new_state);
-}
-
-/*
- * cookie.c
- */
-extern struct kmem_cache *fscache_cookie_jar;
-#ifdef CONFIG_PROC_FS
-extern const struct seq_operations fscache_cookies_seq_ops;
-#endif
-extern struct timer_list fscache_cookie_lru_timer;
-
-extern void fscache_print_cookie(struct fscache_cookie *cookie, char prefix);
-extern bool fscache_begin_cookie_access(struct fscache_cookie *cookie,
-					enum fscache_access_trace why);
-
-static inline void fscache_see_cookie(struct fscache_cookie *cookie,
-				      enum fscache_cookie_trace where)
-{
-	trace_fscache_cookie(cookie->debug_id, refcount_read(&cookie->ref),
-			     where);
-}
-
-/*
- * main.c
- */
-extern unsigned fscache_debug;
-
-extern unsigned int fscache_hash(unsigned int salt, const void *data, size_t len);
-
-/*
- * proc.c
- */
-#ifdef CONFIG_PROC_FS
-extern int __init fscache_proc_init(void);
-extern void fscache_proc_cleanup(void);
-#else
-#define fscache_proc_init()	(0)
-#define fscache_proc_cleanup()	do {} while (0)
-#endif
-
-/*
- * stats.c
- */
-#ifdef CONFIG_FSCACHE_STATS
-extern atomic_t fscache_n_volumes;
-extern atomic_t fscache_n_volumes_collision;
-extern atomic_t fscache_n_volumes_nomem;
-extern atomic_t fscache_n_cookies;
-extern atomic_t fscache_n_cookies_lru;
-extern atomic_t fscache_n_cookies_lru_expired;
-extern atomic_t fscache_n_cookies_lru_removed;
-extern atomic_t fscache_n_cookies_lru_dropped;
-
-extern atomic_t fscache_n_acquires;
-extern atomic_t fscache_n_acquires_ok;
-extern atomic_t fscache_n_acquires_oom;
-
-extern atomic_t fscache_n_invalidates;
-
-extern atomic_t fscache_n_relinquishes;
-extern atomic_t fscache_n_relinquishes_retire;
-extern atomic_t fscache_n_relinquishes_dropped;
-
-extern atomic_t fscache_n_resizes;
-extern atomic_t fscache_n_resizes_null;
-
-static inline void fscache_stat(atomic_t *stat)
-{
-	atomic_inc(stat);
-}
-
-static inline void fscache_stat_d(atomic_t *stat)
-{
-	atomic_dec(stat);
-}
-
-#define __fscache_stat(stat) (stat)
-
-int fscache_stats_show(struct seq_file *m, void *v);
-#else
-
-#define __fscache_stat(stat) (NULL)
-#define fscache_stat(stat) do {} while (0)
-#define fscache_stat_d(stat) do {} while (0)
-#endif
-
-/*
- * volume.c
- */
-#ifdef CONFIG_PROC_FS
-extern const struct seq_operations fscache_volumes_seq_ops;
-#endif
-
-struct fscache_volume *fscache_get_volume(struct fscache_volume *volume,
-					  enum fscache_volume_trace where);
-void fscache_put_volume(struct fscache_volume *volume,
-			enum fscache_volume_trace where);
-bool fscache_begin_volume_access(struct fscache_volume *volume,
-				 struct fscache_cookie *cookie,
-				 enum fscache_access_trace why);
-void fscache_create_volume(struct fscache_volume *volume, bool wait);
-
-
-/*****************************************************************************/
-/*
- * debug tracing
- */
-#define dbgprintk(FMT, ...) \
-	printk("[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
-
-#define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
-#define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
-#define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
-
-#define kjournal(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
-
-#ifdef __KDEBUG
-#define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
-#define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
-#define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
-
-#elif defined(CONFIG_FSCACHE_DEBUG)
-#define _enter(FMT, ...)			\
-do {						\
-	if (__do_kdebug(ENTER))			\
-		kenter(FMT, ##__VA_ARGS__);	\
-} while (0)
-
-#define _leave(FMT, ...)			\
-do {						\
-	if (__do_kdebug(LEAVE))			\
-		kleave(FMT, ##__VA_ARGS__);	\
-} while (0)
-
-#define _debug(FMT, ...)			\
-do {						\
-	if (__do_kdebug(DEBUG))			\
-		kdebug(FMT, ##__VA_ARGS__);	\
-} while (0)
-
-#else
-#define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
-#define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
-#define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
-#endif
-
-/*
- * determine whether a particular optional debugging point should be logged
- * - we need to go through three steps to persuade cpp to correctly join the
- *   shorthand in FSCACHE_DEBUG_LEVEL with its prefix
- */
-#define ____do_kdebug(LEVEL, POINT) \
-	unlikely((fscache_debug & \
-		  (FSCACHE_POINT_##POINT << (FSCACHE_DEBUG_ ## LEVEL * 3))))
-#define ___do_kdebug(LEVEL, POINT) \
-	____do_kdebug(LEVEL, POINT)
-#define __do_kdebug(POINT) \
-	___do_kdebug(FSCACHE_DEBUG_LEVEL, POINT)
-
-#define FSCACHE_DEBUG_CACHE	0
-#define FSCACHE_DEBUG_COOKIE	1
-#define FSCACHE_DEBUG_OBJECT	2
-#define FSCACHE_DEBUG_OPERATION	3
-
-#define FSCACHE_POINT_ENTER	1
-#define FSCACHE_POINT_LEAVE	2
-#define FSCACHE_POINT_DEBUG	4
-
-#ifndef FSCACHE_DEBUG_LEVEL
-#define FSCACHE_DEBUG_LEVEL CACHE
-#endif
-
-/*
- * assertions
- */
-#if 1 /* defined(__KDEBUGALL) */
-
-#define ASSERT(X)							\
-do {									\
-	if (unlikely(!(X))) {						\
-		pr_err("\n");					\
-		pr_err("Assertion failed\n");	\
-		BUG();							\
-	}								\
-} while (0)
-
-#define ASSERTCMP(X, OP, Y)						\
-do {									\
-	if (unlikely(!((X) OP (Y)))) {					\
-		pr_err("\n");					\
-		pr_err("Assertion failed\n");	\
-		pr_err("%lx " #OP " %lx is false\n",		\
-		       (unsigned long)(X), (unsigned long)(Y));		\
-		BUG();							\
-	}								\
-} while (0)
-
-#define ASSERTIF(C, X)							\
-do {									\
-	if (unlikely((C) && !(X))) {					\
-		pr_err("\n");					\
-		pr_err("Assertion failed\n");	\
-		BUG();							\
-	}								\
-} while (0)
-
-#define ASSERTIFCMP(C, X, OP, Y)					\
-do {									\
-	if (unlikely((C) && !((X) OP (Y)))) {				\
-		pr_err("\n");					\
-		pr_err("Assertion failed\n");	\
-		pr_err("%lx " #OP " %lx is false\n",		\
-		       (unsigned long)(X), (unsigned long)(Y));		\
-		BUG();							\
-	}								\
-} while (0)
-
-#else
-
-#define ASSERT(X)			do {} while (0)
-#define ASSERTCMP(X, OP, Y)		do {} while (0)
-#define ASSERTIF(C, X)			do {} while (0)
-#define ASSERTIFCMP(C, X, OP, Y)	do {} while (0)
-
-#endif /* assert or not */
diff --git a/fs/fscache/io.c b/fs/fscache/io.c
deleted file mode 100644
index 0d2b8dec8f..0000000000
--- a/fs/fscache/io.c
+++ /dev/null
@@ -1,327 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* Cache data I/O routines
- *
- * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-#define FSCACHE_DEBUG_LEVEL OPERATION
-#include <linux/fscache-cache.h>
-#include <linux/uio.h>
-#include <linux/bvec.h>
-#include <linux/slab.h>
-#include <linux/uio.h>
-#include "internal.h"
-
-/**
- * fscache_wait_for_operation - Wait for an object become accessible
- * @cres: The cache resources for the operation being performed
- * @want_state: The minimum state the object must be at
- *
- * See if the target cache object is at the specified minimum state of
- * accessibility yet, and if not, wait for it.
- */
-bool fscache_wait_for_operation(struct netfs_cache_resources *cres,
-				enum fscache_want_state want_state)
-{
-	struct fscache_cookie *cookie = fscache_cres_cookie(cres);
-	enum fscache_cookie_state state;
-
-again:
-	if (!fscache_cache_is_live(cookie->volume->cache)) {
-		_leave(" [broken]");
-		return false;
-	}
-
-	state = fscache_cookie_state(cookie);
-	_enter("c=%08x{%u},%x", cookie->debug_id, state, want_state);
-
-	switch (state) {
-	case FSCACHE_COOKIE_STATE_CREATING:
-	case FSCACHE_COOKIE_STATE_INVALIDATING:
-		if (want_state == FSCACHE_WANT_PARAMS)
-			goto ready; /* There can be no content */
-		fallthrough;
-	case FSCACHE_COOKIE_STATE_LOOKING_UP:
-	case FSCACHE_COOKIE_STATE_LRU_DISCARDING:
-		wait_var_event(&cookie->state,
-			       fscache_cookie_state(cookie) != state);
-		goto again;
-
-	case FSCACHE_COOKIE_STATE_ACTIVE:
-		goto ready;
-	case FSCACHE_COOKIE_STATE_DROPPED:
-	case FSCACHE_COOKIE_STATE_RELINQUISHING:
-	default:
-		_leave(" [not live]");
-		return false;
-	}
-
-ready:
-	if (!cres->cache_priv2)
-		return cookie->volume->cache->ops->begin_operation(cres, want_state);
-	return true;
-}
-EXPORT_SYMBOL(fscache_wait_for_operation);
-
-/*
- * Begin an I/O operation on the cache, waiting till we reach the right state.
- *
- * Attaches the resources required to the operation resources record.
- */
-static int fscache_begin_operation(struct netfs_cache_resources *cres,
-				   struct fscache_cookie *cookie,
-				   enum fscache_want_state want_state,
-				   enum fscache_access_trace why)
-{
-	enum fscache_cookie_state state;
-	long timeo;
-	bool once_only = false;
-
-	cres->ops		= NULL;
-	cres->cache_priv	= cookie;
-	cres->cache_priv2	= NULL;
-	cres->debug_id		= cookie->debug_id;
-	cres->inval_counter	= cookie->inval_counter;
-
-	if (!fscache_begin_cookie_access(cookie, why))
-		return -ENOBUFS;
-
-again:
-	spin_lock(&cookie->lock);
-
-	state = fscache_cookie_state(cookie);
-	_enter("c=%08x{%u},%x", cookie->debug_id, state, want_state);
-
-	switch (state) {
-	case FSCACHE_COOKIE_STATE_LOOKING_UP:
-	case FSCACHE_COOKIE_STATE_LRU_DISCARDING:
-	case FSCACHE_COOKIE_STATE_INVALIDATING:
-		goto wait_for_file_wrangling;
-	case FSCACHE_COOKIE_STATE_CREATING:
-		if (want_state == FSCACHE_WANT_PARAMS)
-			goto ready; /* There can be no content */
-		goto wait_for_file_wrangling;
-	case FSCACHE_COOKIE_STATE_ACTIVE:
-		goto ready;
-	case FSCACHE_COOKIE_STATE_DROPPED:
-	case FSCACHE_COOKIE_STATE_RELINQUISHING:
-		WARN(1, "Can't use cookie in state %u\n", cookie->state);
-		goto not_live;
-	default:
-		goto not_live;
-	}
-
-ready:
-	spin_unlock(&cookie->lock);
-	if (!cookie->volume->cache->ops->begin_operation(cres, want_state))
-		goto failed;
-	return 0;
-
-wait_for_file_wrangling:
-	spin_unlock(&cookie->lock);
-	trace_fscache_access(cookie->debug_id, refcount_read(&cookie->ref),
-			     atomic_read(&cookie->n_accesses),
-			     fscache_access_io_wait);
-	timeo = wait_var_event_timeout(&cookie->state,
-				       fscache_cookie_state(cookie) != state, 20 * HZ);
-	if (timeo <= 1 && !once_only) {
-		pr_warn("%s: cookie state change wait timed out: cookie->state=%u state=%u",
-			__func__, fscache_cookie_state(cookie), state);
-		fscache_print_cookie(cookie, 'O');
-		once_only = true;
-	}
-	goto again;
-
-not_live:
-	spin_unlock(&cookie->lock);
-failed:
-	cres->cache_priv = NULL;
-	cres->ops = NULL;
-	fscache_end_cookie_access(cookie, fscache_access_io_not_live);
-	_leave(" = -ENOBUFS");
-	return -ENOBUFS;
-}
-
-int __fscache_begin_read_operation(struct netfs_cache_resources *cres,
-				   struct fscache_cookie *cookie)
-{
-	return fscache_begin_operation(cres, cookie, FSCACHE_WANT_PARAMS,
-				       fscache_access_io_read);
-}
-EXPORT_SYMBOL(__fscache_begin_read_operation);
-
-int __fscache_begin_write_operation(struct netfs_cache_resources *cres,
-				    struct fscache_cookie *cookie)
-{
-	return fscache_begin_operation(cres, cookie, FSCACHE_WANT_PARAMS,
-				       fscache_access_io_write);
-}
-EXPORT_SYMBOL(__fscache_begin_write_operation);
-
-/**
- * fscache_dirty_folio - Mark folio dirty and pin a cache object for writeback
- * @mapping: The mapping the folio belongs to.
- * @folio: The folio being dirtied.
- * @cookie: The cookie referring to the cache object
- *
- * Set the dirty flag on a folio and pin an in-use cache object in memory
- * so that writeback can later write to it.  This is intended
- * to be called from the filesystem's ->dirty_folio() method.
- *
- * Return: true if the dirty flag was set on the folio, false otherwise.
- */
-bool fscache_dirty_folio(struct address_space *mapping, struct folio *folio,
-				struct fscache_cookie *cookie)
-{
-	struct inode *inode = mapping->host;
-	bool need_use = false;
-
-	_enter("");
-
-	if (!filemap_dirty_folio(mapping, folio))
-		return false;
-	if (!fscache_cookie_valid(cookie))
-		return true;
-
-	if (!(inode->i_state & I_PINNING_FSCACHE_WB)) {
-		spin_lock(&inode->i_lock);
-		if (!(inode->i_state & I_PINNING_FSCACHE_WB)) {
-			inode->i_state |= I_PINNING_FSCACHE_WB;
-			need_use = true;
-		}
-		spin_unlock(&inode->i_lock);
-
-		if (need_use)
-			fscache_use_cookie(cookie, true);
-	}
-	return true;
-}
-EXPORT_SYMBOL(fscache_dirty_folio);
-
-struct fscache_write_request {
-	struct netfs_cache_resources cache_resources;
-	struct address_space	*mapping;
-	loff_t			start;
-	size_t			len;
-	bool			set_bits;
-	netfs_io_terminated_t	term_func;
-	void			*term_func_priv;
-};
-
-void __fscache_clear_page_bits(struct address_space *mapping,
-			       loff_t start, size_t len)
-{
-	pgoff_t first = start / PAGE_SIZE;
-	pgoff_t last = (start + len - 1) / PAGE_SIZE;
-	struct page *page;
-
-	if (len) {
-		XA_STATE(xas, &mapping->i_pages, first);
-
-		rcu_read_lock();
-		xas_for_each(&xas, page, last) {
-			end_page_fscache(page);
-		}
-		rcu_read_unlock();
-	}
-}
-EXPORT_SYMBOL(__fscache_clear_page_bits);
-
-/*
- * Deal with the completion of writing the data to the cache.
- */
-static void fscache_wreq_done(void *priv, ssize_t transferred_or_error,
-			      bool was_async)
-{
-	struct fscache_write_request *wreq = priv;
-
-	fscache_clear_page_bits(wreq->mapping, wreq->start, wreq->len,
-				wreq->set_bits);
-
-	if (wreq->term_func)
-		wreq->term_func(wreq->term_func_priv, transferred_or_error,
-				was_async);
-	fscache_end_operation(&wreq->cache_resources);
-	kfree(wreq);
-}
-
-void __fscache_write_to_cache(struct fscache_cookie *cookie,
-			      struct address_space *mapping,
-			      loff_t start, size_t len, loff_t i_size,
-			      netfs_io_terminated_t term_func,
-			      void *term_func_priv,
-			      bool cond)
-{
-	struct fscache_write_request *wreq;
-	struct netfs_cache_resources *cres;
-	struct iov_iter iter;
-	int ret = -ENOBUFS;
-
-	if (len == 0)
-		goto abandon;
-
-	_enter("%llx,%zx", start, len);
-
-	wreq = kzalloc(sizeof(struct fscache_write_request), GFP_NOFS);
-	if (!wreq)
-		goto abandon;
-	wreq->mapping		= mapping;
-	wreq->start		= start;
-	wreq->len		= len;
-	wreq->set_bits		= cond;
-	wreq->term_func		= term_func;
-	wreq->term_func_priv	= term_func_priv;
-
-	cres = &wreq->cache_resources;
-	if (fscache_begin_operation(cres, cookie, FSCACHE_WANT_WRITE,
-				    fscache_access_io_write) < 0)
-		goto abandon_free;
-
-	ret = cres->ops->prepare_write(cres, &start, &len, i_size, false);
-	if (ret < 0)
-		goto abandon_end;
-
-	/* TODO: Consider clearing page bits now for space the write isn't
-	 * covering.  This is more complicated than it appears when THPs are
-	 * taken into account.
-	 */
-
-	iov_iter_xarray(&iter, ITER_SOURCE, &mapping->i_pages, start, len);
-	fscache_write(cres, start, &iter, fscache_wreq_done, wreq);
-	return;
-
-abandon_end:
-	return fscache_wreq_done(wreq, ret, false);
-abandon_free:
-	kfree(wreq);
-abandon:
-	fscache_clear_page_bits(mapping, start, len, cond);
-	if (term_func)
-		term_func(term_func_priv, ret, false);
-}
-EXPORT_SYMBOL(__fscache_write_to_cache);
-
-/*
- * Change the size of a backing object.
- */
-void __fscache_resize_cookie(struct fscache_cookie *cookie, loff_t new_size)
-{
-	struct netfs_cache_resources cres;
-
-	trace_fscache_resize(cookie, new_size);
-	if (fscache_begin_operation(&cres, cookie, FSCACHE_WANT_WRITE,
-				    fscache_access_io_resize) == 0) {
-		fscache_stat(&fscache_n_resizes);
-		set_bit(FSCACHE_COOKIE_NEEDS_UPDATE, &cookie->flags);
-
-		/* We cannot defer a resize as we need to do it inside the
-		 * netfs's inode lock so that we're serialised with respect to
-		 * writes.
-		 */
-		cookie->volume->cache->ops->resize_cookie(&cres, new_size);
-		fscache_end_operation(&cres);
-	} else {
-		fscache_stat(&fscache_n_resizes_null);
-	}
-}
-EXPORT_SYMBOL(__fscache_resize_cookie);
diff --git a/fs/fscache/main.c b/fs/fscache/main.c
deleted file mode 100644
index dad85fd84f..0000000000
--- a/fs/fscache/main.c
+++ /dev/null
@@ -1,121 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* General filesystem local caching manager
- *
- * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#define FSCACHE_DEBUG_LEVEL CACHE
-#include <linux/module.h>
-#include <linux/init.h>
-#define CREATE_TRACE_POINTS
-#include "internal.h"
-
-MODULE_DESCRIPTION("FS Cache Manager");
-MODULE_AUTHOR("Red Hat, Inc.");
-MODULE_LICENSE("GPL");
-
-unsigned fscache_debug;
-module_param_named(debug, fscache_debug, uint,
-		   S_IWUSR | S_IRUGO);
-MODULE_PARM_DESC(fscache_debug,
-		 "FS-Cache debugging mask");
-
-EXPORT_TRACEPOINT_SYMBOL(fscache_access_cache);
-EXPORT_TRACEPOINT_SYMBOL(fscache_access_volume);
-EXPORT_TRACEPOINT_SYMBOL(fscache_access);
-
-struct workqueue_struct *fscache_wq;
-EXPORT_SYMBOL(fscache_wq);
-
-/*
- * Mixing scores (in bits) for (7,20):
- * Input delta: 1-bit      2-bit
- * 1 round:     330.3     9201.6
- * 2 rounds:   1246.4    25475.4
- * 3 rounds:   1907.1    31295.1
- * 4 rounds:   2042.3    31718.6
- * Perfect:    2048      31744
- *            (32*64)   (32*31/2 * 64)
- */
-#define HASH_MIX(x, y, a)	\
-	(	x ^= (a),	\
-	y ^= x,	x = rol32(x, 7),\
-	x += y,	y = rol32(y,20),\
-	y *= 9			)
-
-static inline unsigned int fold_hash(unsigned long x, unsigned long y)
-{
-	/* Use arch-optimized multiply if one exists */
-	return __hash_32(y ^ __hash_32(x));
-}
-
-/*
- * Generate a hash.  This is derived from full_name_hash(), but we want to be
- * sure it is arch independent and that it doesn't change as bits of the
- * computed hash value might appear on disk.  The caller must guarantee that
- * the source data is a multiple of four bytes in size.
- */
-unsigned int fscache_hash(unsigned int salt, const void *data, size_t len)
-{
-	const __le32 *p = data;
-	unsigned int a, x = 0, y = salt, n = len / sizeof(__le32);
-
-	for (; n; n--) {
-		a = le32_to_cpu(*p++);
-		HASH_MIX(x, y, a);
-	}
-	return fold_hash(x, y);
-}
-
-/*
- * initialise the fs caching module
- */
-static int __init fscache_init(void)
-{
-	int ret = -ENOMEM;
-
-	fscache_wq = alloc_workqueue("fscache", WQ_UNBOUND | WQ_FREEZABLE, 0);
-	if (!fscache_wq)
-		goto error_wq;
-
-	ret = fscache_proc_init();
-	if (ret < 0)
-		goto error_proc;
-
-	fscache_cookie_jar = kmem_cache_create("fscache_cookie_jar",
-					       sizeof(struct fscache_cookie),
-					       0, 0, NULL);
-	if (!fscache_cookie_jar) {
-		pr_notice("Failed to allocate a cookie jar\n");
-		ret = -ENOMEM;
-		goto error_cookie_jar;
-	}
-
-	pr_notice("Loaded\n");
-	return 0;
-
-error_cookie_jar:
-	fscache_proc_cleanup();
-error_proc:
-	destroy_workqueue(fscache_wq);
-error_wq:
-	return ret;
-}
-
-fs_initcall(fscache_init);
-
-/*
- * clean up on module removal
- */
-static void __exit fscache_exit(void)
-{
-	_enter("");
-
-	kmem_cache_destroy(fscache_cookie_jar);
-	fscache_proc_cleanup();
-	destroy_workqueue(fscache_wq);
-	pr_notice("Unloaded\n");
-}
-
-module_exit(fscache_exit);
diff --git a/fs/fscache/proc.c b/fs/fscache/proc.c
deleted file mode 100644
index dc3b0e9c8c..0000000000
--- a/fs/fscache/proc.c
+++ /dev/null
@@ -1,54 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* FS-Cache statistics viewing interface
- *
- * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#define FSCACHE_DEBUG_LEVEL CACHE
-#include <linux/module.h>
-#include <linux/proc_fs.h>
-#include <linux/seq_file.h>
-#include "internal.h"
-
-/*
- * initialise the /proc/fs/fscache/ directory
- */
-int __init fscache_proc_init(void)
-{
-	if (!proc_mkdir("fs/fscache", NULL))
-		goto error_dir;
-
-	if (!proc_create_seq("fs/fscache/caches", S_IFREG | 0444, NULL,
-			     &fscache_caches_seq_ops))
-		goto error;
-
-	if (!proc_create_seq("fs/fscache/volumes", S_IFREG | 0444, NULL,
-			     &fscache_volumes_seq_ops))
-		goto error;
-
-	if (!proc_create_seq("fs/fscache/cookies", S_IFREG | 0444, NULL,
-			     &fscache_cookies_seq_ops))
-		goto error;
-
-#ifdef CONFIG_FSCACHE_STATS
-	if (!proc_create_single("fs/fscache/stats", S_IFREG | 0444, NULL,
-				fscache_stats_show))
-		goto error;
-#endif
-
-	return 0;
-
-error:
-	remove_proc_entry("fs/fscache", NULL);
-error_dir:
-	return -ENOMEM;
-}
-
-/*
- * clean up the /proc/fs/fscache/ directory
- */
-void fscache_proc_cleanup(void)
-{
-	remove_proc_subtree("fs/fscache", NULL);
-}
diff --git a/fs/fscache/stats.c b/fs/fscache/stats.c
deleted file mode 100644
index fc94e5e79f..0000000000
--- a/fs/fscache/stats.c
+++ /dev/null
@@ -1,102 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* FS-Cache statistics
- *
- * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#define FSCACHE_DEBUG_LEVEL CACHE
-#include <linux/proc_fs.h>
-#include <linux/seq_file.h>
-#include "internal.h"
-
-/*
- * operation counters
- */
-atomic_t fscache_n_volumes;
-atomic_t fscache_n_volumes_collision;
-atomic_t fscache_n_volumes_nomem;
-atomic_t fscache_n_cookies;
-atomic_t fscache_n_cookies_lru;
-atomic_t fscache_n_cookies_lru_expired;
-atomic_t fscache_n_cookies_lru_removed;
-atomic_t fscache_n_cookies_lru_dropped;
-
-atomic_t fscache_n_acquires;
-atomic_t fscache_n_acquires_ok;
-atomic_t fscache_n_acquires_oom;
-
-atomic_t fscache_n_invalidates;
-
-atomic_t fscache_n_updates;
-EXPORT_SYMBOL(fscache_n_updates);
-
-atomic_t fscache_n_relinquishes;
-atomic_t fscache_n_relinquishes_retire;
-atomic_t fscache_n_relinquishes_dropped;
-
-atomic_t fscache_n_resizes;
-atomic_t fscache_n_resizes_null;
-
-atomic_t fscache_n_read;
-EXPORT_SYMBOL(fscache_n_read);
-atomic_t fscache_n_write;
-EXPORT_SYMBOL(fscache_n_write);
-atomic_t fscache_n_no_write_space;
-EXPORT_SYMBOL(fscache_n_no_write_space);
-atomic_t fscache_n_no_create_space;
-EXPORT_SYMBOL(fscache_n_no_create_space);
-atomic_t fscache_n_culled;
-EXPORT_SYMBOL(fscache_n_culled);
-
-/*
- * display the general statistics
- */
-int fscache_stats_show(struct seq_file *m, void *v)
-{
-	seq_puts(m, "FS-Cache statistics\n");
-	seq_printf(m, "Cookies: n=%d v=%d vcol=%u voom=%u\n",
-		   atomic_read(&fscache_n_cookies),
-		   atomic_read(&fscache_n_volumes),
-		   atomic_read(&fscache_n_volumes_collision),
-		   atomic_read(&fscache_n_volumes_nomem)
-		   );
-
-	seq_printf(m, "Acquire: n=%u ok=%u oom=%u\n",
-		   atomic_read(&fscache_n_acquires),
-		   atomic_read(&fscache_n_acquires_ok),
-		   atomic_read(&fscache_n_acquires_oom));
-
-	seq_printf(m, "LRU    : n=%u exp=%u rmv=%u drp=%u at=%ld\n",
-		   atomic_read(&fscache_n_cookies_lru),
-		   atomic_read(&fscache_n_cookies_lru_expired),
-		   atomic_read(&fscache_n_cookies_lru_removed),
-		   atomic_read(&fscache_n_cookies_lru_dropped),
-		   timer_pending(&fscache_cookie_lru_timer) ?
-		   fscache_cookie_lru_timer.expires - jiffies : 0);
-
-	seq_printf(m, "Invals : n=%u\n",
-		   atomic_read(&fscache_n_invalidates));
-
-	seq_printf(m, "Updates: n=%u rsz=%u rsn=%u\n",
-		   atomic_read(&fscache_n_updates),
-		   atomic_read(&fscache_n_resizes),
-		   atomic_read(&fscache_n_resizes_null));
-
-	seq_printf(m, "Relinqs: n=%u rtr=%u drop=%u\n",
-		   atomic_read(&fscache_n_relinquishes),
-		   atomic_read(&fscache_n_relinquishes_retire),
-		   atomic_read(&fscache_n_relinquishes_dropped));
-
-	seq_printf(m, "NoSpace: nwr=%u ncr=%u cull=%u\n",
-		   atomic_read(&fscache_n_no_write_space),
-		   atomic_read(&fscache_n_no_create_space),
-		   atomic_read(&fscache_n_culled));
-
-	seq_printf(m, "IO     : rd=%u wr=%u\n",
-		   atomic_read(&fscache_n_read),
-		   atomic_read(&fscache_n_write));
-
-	netfs_stats_show(m);
-	return 0;
-}
diff --git a/fs/fscache/volume.c b/fs/fscache/volume.c
deleted file mode 100644
index cdf991bdd9..0000000000
--- a/fs/fscache/volume.c
+++ /dev/null
@@ -1,520 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* Volume-level cache cookie handling.
- *
- * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#define FSCACHE_DEBUG_LEVEL COOKIE
-#include <linux/export.h>
-#include <linux/slab.h>
-#include "internal.h"
-
-#define fscache_volume_hash_shift 10
-static struct hlist_bl_head fscache_volume_hash[1 << fscache_volume_hash_shift];
-static atomic_t fscache_volume_debug_id;
-static LIST_HEAD(fscache_volumes);
-
-static void fscache_create_volume_work(struct work_struct *work);
-
-struct fscache_volume *fscache_get_volume(struct fscache_volume *volume,
-					  enum fscache_volume_trace where)
-{
-	int ref;
-
-	__refcount_inc(&volume->ref, &ref);
-	trace_fscache_volume(volume->debug_id, ref + 1, where);
-	return volume;
-}
-
-static void fscache_see_volume(struct fscache_volume *volume,
-			       enum fscache_volume_trace where)
-{
-	int ref = refcount_read(&volume->ref);
-
-	trace_fscache_volume(volume->debug_id, ref, where);
-}
-
-/*
- * Pin the cache behind a volume so that we can access it.
- */
-static void __fscache_begin_volume_access(struct fscache_volume *volume,
-					  struct fscache_cookie *cookie,
-					  enum fscache_access_trace why)
-{
-	int n_accesses;
-
-	n_accesses = atomic_inc_return(&volume->n_accesses);
-	smp_mb__after_atomic();
-	trace_fscache_access_volume(volume->debug_id, cookie ? cookie->debug_id : 0,
-				    refcount_read(&volume->ref),
-				    n_accesses, why);
-}
-
-/**
- * fscache_begin_volume_access - Pin a cache so a volume can be accessed
- * @volume: The volume cookie
- * @cookie: A datafile cookie for a tracing reference (or NULL)
- * @why: An indication of the circumstances of the access for tracing
- *
- * Attempt to pin the cache to prevent it from going away whilst we're
- * accessing a volume and returns true if successful.  This works as follows:
- *
- *  (1) If the cache tests as not live (state is not FSCACHE_CACHE_IS_ACTIVE),
- *      then we return false to indicate access was not permitted.
- *
- *  (2) If the cache tests as live, then we increment the volume's n_accesses
- *      count and then recheck the cache liveness, ending the access if it
- *      ceased to be live.
- *
- *  (3) When we end the access, we decrement the volume's n_accesses and wake
- *      up the any waiters if it reaches 0.
- *
- *  (4) Whilst the cache is caching, the volume's n_accesses is kept
- *      artificially incremented to prevent wakeups from happening.
- *
- *  (5) When the cache is taken offline, the state is changed to prevent new
- *      accesses, the volume's n_accesses is decremented and we wait for it to
- *      become 0.
- *
- * The datafile @cookie and the @why indicator are merely provided for tracing
- * purposes.
- */
-bool fscache_begin_volume_access(struct fscache_volume *volume,
-				 struct fscache_cookie *cookie,
-				 enum fscache_access_trace why)
-{
-	if (!fscache_cache_is_live(volume->cache))
-		return false;
-	__fscache_begin_volume_access(volume, cookie, why);
-	if (!fscache_cache_is_live(volume->cache)) {
-		fscache_end_volume_access(volume, cookie, fscache_access_unlive);
-		return false;
-	}
-	return true;
-}
-
-/**
- * fscache_end_volume_access - Unpin a cache at the end of an access.
- * @volume: The volume cookie
- * @cookie: A datafile cookie for a tracing reference (or NULL)
- * @why: An indication of the circumstances of the access for tracing
- *
- * Unpin a cache volume after we've accessed it.  The datafile @cookie and the
- * @why indicator are merely provided for tracing purposes.
- */
-void fscache_end_volume_access(struct fscache_volume *volume,
-			       struct fscache_cookie *cookie,
-			       enum fscache_access_trace why)
-{
-	int n_accesses;
-
-	smp_mb__before_atomic();
-	n_accesses = atomic_dec_return(&volume->n_accesses);
-	trace_fscache_access_volume(volume->debug_id, cookie ? cookie->debug_id : 0,
-				    refcount_read(&volume->ref),
-				    n_accesses, why);
-	if (n_accesses == 0)
-		wake_up_var(&volume->n_accesses);
-}
-EXPORT_SYMBOL(fscache_end_volume_access);
-
-static bool fscache_volume_same(const struct fscache_volume *a,
-				const struct fscache_volume *b)
-{
-	size_t klen;
-
-	if (a->key_hash	!= b->key_hash ||
-	    a->cache	!= b->cache ||
-	    a->key[0]	!= b->key[0])
-		return false;
-
-	klen = round_up(a->key[0] + 1, sizeof(__le32));
-	return memcmp(a->key, b->key, klen) == 0;
-}
-
-static bool fscache_is_acquire_pending(struct fscache_volume *volume)
-{
-	return test_bit(FSCACHE_VOLUME_ACQUIRE_PENDING, &volume->flags);
-}
-
-static void fscache_wait_on_volume_collision(struct fscache_volume *candidate,
-					     unsigned int collidee_debug_id)
-{
-	wait_on_bit_timeout(&candidate->flags, FSCACHE_VOLUME_ACQUIRE_PENDING,
-			    TASK_UNINTERRUPTIBLE, 20 * HZ);
-	if (fscache_is_acquire_pending(candidate)) {
-		pr_notice("Potential volume collision new=%08x old=%08x",
-			  candidate->debug_id, collidee_debug_id);
-		fscache_stat(&fscache_n_volumes_collision);
-		wait_on_bit(&candidate->flags, FSCACHE_VOLUME_ACQUIRE_PENDING,
-			    TASK_UNINTERRUPTIBLE);
-	}
-}
-
-/*
- * Attempt to insert the new volume into the hash.  If there's a collision, we
- * wait for the old volume to complete if it's being relinquished and an error
- * otherwise.
- */
-static bool fscache_hash_volume(struct fscache_volume *candidate)
-{
-	struct fscache_volume *cursor;
-	struct hlist_bl_head *h;
-	struct hlist_bl_node *p;
-	unsigned int bucket, collidee_debug_id = 0;
-
-	bucket = candidate->key_hash & (ARRAY_SIZE(fscache_volume_hash) - 1);
-	h = &fscache_volume_hash[bucket];
-
-	hlist_bl_lock(h);
-	hlist_bl_for_each_entry(cursor, p, h, hash_link) {
-		if (fscache_volume_same(candidate, cursor)) {
-			if (!test_bit(FSCACHE_VOLUME_RELINQUISHED, &cursor->flags))
-				goto collision;
-			fscache_see_volume(cursor, fscache_volume_get_hash_collision);
-			set_bit(FSCACHE_VOLUME_COLLIDED_WITH, &cursor->flags);
-			set_bit(FSCACHE_VOLUME_ACQUIRE_PENDING, &candidate->flags);
-			collidee_debug_id = cursor->debug_id;
-			break;
-		}
-	}
-
-	hlist_bl_add_head(&candidate->hash_link, h);
-	hlist_bl_unlock(h);
-
-	if (fscache_is_acquire_pending(candidate))
-		fscache_wait_on_volume_collision(candidate, collidee_debug_id);
-	return true;
-
-collision:
-	fscache_see_volume(cursor, fscache_volume_collision);
-	hlist_bl_unlock(h);
-	return false;
-}
-
-/*
- * Allocate and initialise a volume representation cookie.
- */
-static struct fscache_volume *fscache_alloc_volume(const char *volume_key,
-						   const char *cache_name,
-						   const void *coherency_data,
-						   size_t coherency_len)
-{
-	struct fscache_volume *volume;
-	struct fscache_cache *cache;
-	size_t klen, hlen;
-	u8 *key;
-
-	klen = strlen(volume_key);
-	if (klen > NAME_MAX)
-		return NULL;
-
-	if (!coherency_data)
-		coherency_len = 0;
-
-	cache = fscache_lookup_cache(cache_name, false);
-	if (IS_ERR(cache))
-		return NULL;
-
-	volume = kzalloc(struct_size(volume, coherency, coherency_len),
-			 GFP_KERNEL);
-	if (!volume)
-		goto err_cache;
-
-	volume->cache = cache;
-	volume->coherency_len = coherency_len;
-	if (coherency_data)
-		memcpy(volume->coherency, coherency_data, coherency_len);
-	INIT_LIST_HEAD(&volume->proc_link);
-	INIT_WORK(&volume->work, fscache_create_volume_work);
-	refcount_set(&volume->ref, 1);
-	spin_lock_init(&volume->lock);
-
-	/* Stick the length on the front of the key and pad it out to make
-	 * hashing easier.
-	 */
-	hlen = round_up(1 + klen + 1, sizeof(__le32));
-	key = kzalloc(hlen, GFP_KERNEL);
-	if (!key)
-		goto err_vol;
-	key[0] = klen;
-	memcpy(key + 1, volume_key, klen);
-
-	volume->key = key;
-	volume->key_hash = fscache_hash(0, key, hlen);
-
-	volume->debug_id = atomic_inc_return(&fscache_volume_debug_id);
-	down_write(&fscache_addremove_sem);
-	atomic_inc(&cache->n_volumes);
-	list_add_tail(&volume->proc_link, &fscache_volumes);
-	fscache_see_volume(volume, fscache_volume_new_acquire);
-	fscache_stat(&fscache_n_volumes);
-	up_write(&fscache_addremove_sem);
-	_leave(" = v=%x", volume->debug_id);
-	return volume;
-
-err_vol:
-	kfree(volume);
-err_cache:
-	fscache_put_cache(cache, fscache_cache_put_alloc_volume);
-	fscache_stat(&fscache_n_volumes_nomem);
-	return NULL;
-}
-
-/*
- * Create a volume's representation on disk.  Have a volume ref and a cache
- * access we have to release.
- */
-static void fscache_create_volume_work(struct work_struct *work)
-{
-	const struct fscache_cache_ops *ops;
-	struct fscache_volume *volume =
-		container_of(work, struct fscache_volume, work);
-
-	fscache_see_volume(volume, fscache_volume_see_create_work);
-
-	ops = volume->cache->ops;
-	if (ops->acquire_volume)
-		ops->acquire_volume(volume);
-	fscache_end_cache_access(volume->cache,
-				 fscache_access_acquire_volume_end);
-
-	clear_and_wake_up_bit(FSCACHE_VOLUME_CREATING, &volume->flags);
-	fscache_put_volume(volume, fscache_volume_put_create_work);
-}
-
-/*
- * Dispatch a worker thread to create a volume's representation on disk.
- */
-void fscache_create_volume(struct fscache_volume *volume, bool wait)
-{
-	if (test_and_set_bit(FSCACHE_VOLUME_CREATING, &volume->flags))
-		goto maybe_wait;
-	if (volume->cache_priv)
-		goto no_wait; /* We raced */
-	if (!fscache_begin_cache_access(volume->cache,
-					fscache_access_acquire_volume))
-		goto no_wait;
-
-	fscache_get_volume(volume, fscache_volume_get_create_work);
-	if (!schedule_work(&volume->work))
-		fscache_put_volume(volume, fscache_volume_put_create_work);
-
-maybe_wait:
-	if (wait) {
-		fscache_see_volume(volume, fscache_volume_wait_create_work);
-		wait_on_bit(&volume->flags, FSCACHE_VOLUME_CREATING,
-			    TASK_UNINTERRUPTIBLE);
-	}
-	return;
-no_wait:
-	clear_bit_unlock(FSCACHE_VOLUME_CREATING, &volume->flags);
-	wake_up_bit(&volume->flags, FSCACHE_VOLUME_CREATING);
-}
-
-/*
- * Acquire a volume representation cookie and link it to a (proposed) cache.
- */
-struct fscache_volume *__fscache_acquire_volume(const char *volume_key,
-						const char *cache_name,
-						const void *coherency_data,
-						size_t coherency_len)
-{
-	struct fscache_volume *volume;
-
-	volume = fscache_alloc_volume(volume_key, cache_name,
-				      coherency_data, coherency_len);
-	if (!volume)
-		return ERR_PTR(-ENOMEM);
-
-	if (!fscache_hash_volume(volume)) {
-		fscache_put_volume(volume, fscache_volume_put_hash_collision);
-		return ERR_PTR(-EBUSY);
-	}
-
-	fscache_create_volume(volume, false);
-	return volume;
-}
-EXPORT_SYMBOL(__fscache_acquire_volume);
-
-static void fscache_wake_pending_volume(struct fscache_volume *volume,
-					struct hlist_bl_head *h)
-{
-	struct fscache_volume *cursor;
-	struct hlist_bl_node *p;
-
-	hlist_bl_for_each_entry(cursor, p, h, hash_link) {
-		if (fscache_volume_same(cursor, volume)) {
-			fscache_see_volume(cursor, fscache_volume_see_hash_wake);
-			clear_and_wake_up_bit(FSCACHE_VOLUME_ACQUIRE_PENDING,
-					      &cursor->flags);
-			return;
-		}
-	}
-}
-
-/*
- * Remove a volume cookie from the hash table.
- */
-static void fscache_unhash_volume(struct fscache_volume *volume)
-{
-	struct hlist_bl_head *h;
-	unsigned int bucket;
-
-	bucket = volume->key_hash & (ARRAY_SIZE(fscache_volume_hash) - 1);
-	h = &fscache_volume_hash[bucket];
-
-	hlist_bl_lock(h);
-	hlist_bl_del(&volume->hash_link);
-	if (test_bit(FSCACHE_VOLUME_COLLIDED_WITH, &volume->flags))
-		fscache_wake_pending_volume(volume, h);
-	hlist_bl_unlock(h);
-}
-
-/*
- * Drop a cache's volume attachments.
- */
-static void fscache_free_volume(struct fscache_volume *volume)
-{
-	struct fscache_cache *cache = volume->cache;
-
-	if (volume->cache_priv) {
-		__fscache_begin_volume_access(volume, NULL,
-					      fscache_access_relinquish_volume);
-		if (volume->cache_priv)
-			cache->ops->free_volume(volume);
-		fscache_end_volume_access(volume, NULL,
-					  fscache_access_relinquish_volume_end);
-	}
-
-	down_write(&fscache_addremove_sem);
-	list_del_init(&volume->proc_link);
-	atomic_dec(&volume->cache->n_volumes);
-	up_write(&fscache_addremove_sem);
-
-	if (!hlist_bl_unhashed(&volume->hash_link))
-		fscache_unhash_volume(volume);
-
-	trace_fscache_volume(volume->debug_id, 0, fscache_volume_free);
-	kfree(volume->key);
-	kfree(volume);
-	fscache_stat_d(&fscache_n_volumes);
-	fscache_put_cache(cache, fscache_cache_put_volume);
-}
-
-/*
- * Drop a reference to a volume cookie.
- */
-void fscache_put_volume(struct fscache_volume *volume,
-			enum fscache_volume_trace where)
-{
-	if (volume) {
-		unsigned int debug_id = volume->debug_id;
-		bool zero;
-		int ref;
-
-		zero = __refcount_dec_and_test(&volume->ref, &ref);
-		trace_fscache_volume(debug_id, ref - 1, where);
-		if (zero)
-			fscache_free_volume(volume);
-	}
-}
-
-/*
- * Relinquish a volume representation cookie.
- */
-void __fscache_relinquish_volume(struct fscache_volume *volume,
-				 const void *coherency_data,
-				 bool invalidate)
-{
-	if (WARN_ON(test_and_set_bit(FSCACHE_VOLUME_RELINQUISHED, &volume->flags)))
-		return;
-
-	if (invalidate) {
-		set_bit(FSCACHE_VOLUME_INVALIDATE, &volume->flags);
-	} else if (coherency_data) {
-		memcpy(volume->coherency, coherency_data, volume->coherency_len);
-	}
-
-	fscache_put_volume(volume, fscache_volume_put_relinquish);
-}
-EXPORT_SYMBOL(__fscache_relinquish_volume);
-
-/**
- * fscache_withdraw_volume - Withdraw a volume from being cached
- * @volume: Volume cookie
- *
- * Withdraw a cache volume from service, waiting for all accesses to complete
- * before returning.
- */
-void fscache_withdraw_volume(struct fscache_volume *volume)
-{
-	int n_accesses;
-
-	_debug("withdraw V=%x", volume->debug_id);
-
-	/* Allow wakeups on dec-to-0 */
-	n_accesses = atomic_dec_return(&volume->n_accesses);
-	trace_fscache_access_volume(volume->debug_id, 0,
-				    refcount_read(&volume->ref),
-				    n_accesses, fscache_access_cache_unpin);
-
-	wait_var_event(&volume->n_accesses,
-		       atomic_read(&volume->n_accesses) == 0);
-}
-EXPORT_SYMBOL(fscache_withdraw_volume);
-
-#ifdef CONFIG_PROC_FS
-/*
- * Generate a list of volumes in /proc/fs/fscache/volumes
- */
-static int fscache_volumes_seq_show(struct seq_file *m, void *v)
-{
-	struct fscache_volume *volume;
-
-	if (v == &fscache_volumes) {
-		seq_puts(m,
-			 "VOLUME   REF   nCOOK ACC FL CACHE           KEY\n"
-			 "======== ===== ===== === == =============== ================\n");
-		return 0;
-	}
-
-	volume = list_entry(v, struct fscache_volume, proc_link);
-	seq_printf(m,
-		   "%08x %5d %5d %3d %02lx %-15.15s %s\n",
-		   volume->debug_id,
-		   refcount_read(&volume->ref),
-		   atomic_read(&volume->n_cookies),
-		   atomic_read(&volume->n_accesses),
-		   volume->flags,
-		   volume->cache->name ?: "-",
-		   volume->key + 1);
-	return 0;
-}
-
-static void *fscache_volumes_seq_start(struct seq_file *m, loff_t *_pos)
-	__acquires(&fscache_addremove_sem)
-{
-	down_read(&fscache_addremove_sem);
-	return seq_list_start_head(&fscache_volumes, *_pos);
-}
-
-static void *fscache_volumes_seq_next(struct seq_file *m, void *v, loff_t *_pos)
-{
-	return seq_list_next(v, &fscache_volumes, _pos);
-}
-
-static void fscache_volumes_seq_stop(struct seq_file *m, void *v)
-	__releases(&fscache_addremove_sem)
-{
-	up_read(&fscache_addremove_sem);
-}
-
-const struct seq_operations fscache_volumes_seq_ops = {
-	.start  = fscache_volumes_seq_start,
-	.next   = fscache_volumes_seq_next,
-	.stop   = fscache_volumes_seq_stop,
-	.show   = fscache_volumes_seq_show,
-};
-#endif /* CONFIG_PROC_FS */