Merge tag 'fscache-rewrite-20220111' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull fscache rewrite from David Howells:
 "This is a set of patches that rewrites the fscache driver and the
  cachefiles driver, significantly simplifying the code compared to
  what's upstream, removing the complex operation scheduling and object
  state machine in favour of something much smaller and simpler.

  The series is structured such that the first few patches disable
  fscache use by the network filesystems using it, remove the cachefiles
  driver entirely and as much of the fscache driver as can be got away
  with without causing build failures in the network filesystems.

  The patches after that recreate fscache and then cachefiles,
  attempting to add the pieces in a logical order. Finally, the
  filesystems are reenabled and then the very last patch changes the
  documentation.

  [!] Note: I have dropped the cifs patch for the moment, leaving local
      caching in cifs disabled. I've been having trouble getting that
      working. I think I have it done, but it needs more testing (there
      seem to be some test failures occurring with v5.16 also from
      xfstests), so I propose deferring that patch to the end of the
      merge window.

  WHY REWRITE?
  ============

  Fscache's operation scheduling API was intended to handle sequencing
  of cache operations, which were all required (where possible) to run
  asynchronously in parallel with the operations being done by the
  network filesystem, whilst allowing the cache to be brought online and
  offline and to interrupt service for invalidation.

  With the advent of the tmpfile capacity in the VFS, however, an
  opportunity arises to do invalidation much more simply, without having
  to wait for I/O that's actually in progress: Cachefiles can simply
  create a tmpfile, cut over the file pointer for the backing object
  attached to a cookie and abandon the in-progress I/O, dismissing it
  upon completion.

  Future work here would involve using Omar Sandoval's vfs_link() with
  AT_LINK_REPLACE[1] to allow an extant file to be displaced by a new
  hard link from a tmpfile as currently I have to unlink the old file
  first.

  These patches can also simplify the object state handling as I/O
  operations to the cache don't all have to be brought to a stop in
  order to invalidate a file. To that end, and with an eye on to writing
  a new backing cache model in the future, I've taken the opportunity to
  simplify the indexing structure.

  I've separated the index cookie concept from the file cookie concept
  by C type now. The former is now called a "volume cookie" (struct
  fscache_volume) and there is a container of file cookies. There are
  then just the two levels. All the index cookie levels are collapsed
  into a single volume cookie, and this has a single printable string as
  a key. For instance, an AFS volume would have a key of something like
  "afs,example.com,1000555", combining the filesystem name, cell name
  and volume ID. This is freeform, but must not have '/' chars in it.

  I've also eliminated all pointers back from fscache into the network
  filesystem. This required the duplication of a little bit of data in
  the cookie (cookie key, coherency data and file size), but it's not
  actually that much. This gets rid of problems with making sure we keep
  netfs data structures around so that the cache can access them.

  These patches mean that most of the code that was in the drivers
  before is simply gone and those drivers are now almost entirely new
  code. That being the case, there doesn't seem any particular reason to
  try and maintain bisectability across it. Further, there has to be a
  point in the middle where things are cut over as there's a single
  point everything has to go through (ie. /dev/cachefiles) and it can't
  be in use by two drivers at once.

  ISSUES YET OUTSTANDING
  ======================

  There are some issues still outstanding, unaddressed by this patchset,
  that will need fixing in future patchsets, but that don't stop this
  series from being usable:

  (1) The cachefiles driver needs to stop using the backing filesystem's
      metadata to store information about what parts of the cache are
      populated. This is not reliable with modern extent-based
      filesystems.

      Fixing this is deferred to a separate patchset as it involves
      negotiation with the network filesystem and the VM as to how much
      data to download to fulfil a read - which brings me on to (2)...

  (2) NFS (and CIFS with the dropped patch) do not take account of how
      the cache would like I/O to be structured to meet its granularity
      requirements. Previously, the cache used page granularity, which
      was fine as the network filesystems also dealt in page
      granularity, and the backing filesystem (ext4, xfs or whatever)
      did whatever it did out of sight. However, we now have folios to
      deal with and the cache will now have to store its own metadata to
      track its contents.

      The change I'm looking at making for cachefiles is to store
      content bitmaps in one or more xattrs and making a bit in the map
      correspond to something like a 256KiB block. However, the size of
      an xattr and the fact that they have to be read/updated in one go
      means that I'm looking at covering 1GiB of data per 512-byte map
      and storing each map in an xattr. Cachefiles has the potential to
      grow into a fully fledged filesystem of its very own if I'm not
      careful.

      However, I'm also looking at changing things even more radically
      and going to a different model of how the cache is arranged and
      managed - one that's more akin to the way, say, openafs does
      things - which brings me on to (3)...

  (3) The way cachefilesd does culling is very inefficient for large
      caches and it would be better to move it into the kernel if I can
      as cachefilesd has to keep asking the kernel if it can cull a
      file. Changing the way the backend works would allow this to be
      addressed.

  BITS THAT MAY BE CONTROVERSIAL
  ==============================

  There are some bits I've added that may be controversial:

  (1) I've provided a flag, S_KERNEL_FILE, that cachefiles uses to check
      if a files is already being used by some other kernel service
      (e.g. a duplicate cachefiles cache in the same directory) and
      reject it if it is. This isn't entirely necessary, but it helps
      prevent accidental data corruption.

      I don't want to use S_SWAPFILE as that has other effects, but
      quite possibly swapon() should set S_KERNEL_FILE too.

      Note that it doesn't prevent userspace from interfering, though
      perhaps it should. (I have made it prevent a marked directory from
      being rmdir-able).

  (2) Cachefiles wants to keep the backing file for a cookie open whilst
      we might need to write to it from network filesystem writeback.
      The problem is that the network filesystem unuses its cookie when
      its file is closed, and so we have nothing pinning the cachefiles
      file open and it will get closed automatically after a short time
      to avoid EMFILE/ENFILE problems.

      Reopening the cache file, however, is a problem if this is being
      done due to writeback triggered by exit(). Some filesystems will
      oops if we try to open a file in that context because they want to
      access current->fs or suchlike.

      To get around this, I added the following:

      (A) An inode flag, I_PINNING_FSCACHE_WB, to be set on a network
          filesystem inode to indicate that we have a usage count on the
          cookie caching that inode.

      (B) A flag in struct writeback_control, unpinned_fscache_wb, that
          is set when __writeback_single_inode() clears the last dirty
          page from i_pages - at which point it clears
          I_PINNING_FSCACHE_WB and sets this flag.

          This has to be done here so that clearing I_PINNING_FSCACHE_WB
          can be done atomically with the check of PAGECACHE_TAG_DIRTY
          that clears I_DIRTY_PAGES.

      (C) A function, fscache_set_page_dirty(), which if it is not set,
          sets I_PINNING_FSCACHE_WB and calls fscache_use_cookie() to
          pin the cache resources.

      (D) A function, fscache_unpin_writeback(), to be called by
          ->write_inode() to unuse the cookie.

      (E) A function, fscache_clear_inode_writeback(), to be called when
          the inode is evicted, before clear_inode() is called. This
          cleans up any lingering I_PINNING_FSCACHE_WB.

      The network filesystem can then use these tools to make sure that
      fscache_write_to_cache() can write locally modified data to the
      cache as well as to the server.

      For the future, I'm working on write helpers for netfs lib that
      should allow this facility to be removed by keeping track of the
      dirty regions separately - but that's incomplete at the moment and
      is also going to be affected by folios, one way or another, since
      it deals with pages"

Link: https://lore.kernel.org/all/510611.1641942444@warthog.procyon.org.uk/
Tested-by: Dominique Martinet <asmadeus@codewreck.org> # 9p
Tested-by: kafs-testing@auristor.com # afs
Tested-by: Jeff Layton <jlayton@kernel.org> # ceph
Tested-by: Dave Wysochanski <dwysocha@redhat.com> # nfs
Tested-by: Daire Byrne <daire@dneg.com> # nfs

* tag 'fscache-rewrite-20220111' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (67 commits)
  9p, afs, ceph, nfs: Use current_is_kswapd() rather than gfpflags_allow_blocking()
  fscache: Add a tracepoint for cookie use/unuse
  fscache: Rewrite documentation
  ceph: add fscache writeback support
  ceph: conversion to new fscache API
  nfs: Implement cache I/O by accessing the cache directly
  nfs: Convert to new fscache volume/cookie API
  9p: Copy local writes to the cache when writing to the server
  9p: Use fscache indexing rewrite and reenable caching
  afs: Skip truncation on the server of data we haven't written yet
  afs: Copy local writes to the cache when writing to the server
  afs: Convert afs to use the new fscache API
  fscache, cachefiles: Display stat of culling events
  fscache, cachefiles: Display stats of no-space events
  cachefiles: Allow cachefiles to actually function
  fscache, cachefiles: Store the volume coherency data
  cachefiles: Implement the I/O routines
  cachefiles: Implement cookie resize for truncate
  cachefiles: Implement begin and end I/O operation
  cachefiles: Implement backing file wrangling
  ...

10 files changed, 1290 insertions, 1549 deletions

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 58e911cb3885..f5d3bf5b69a6 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2173,6 +2173,7 @@ struct super_operations {
 #define S_ENCRYPTED	(1 << 14) /* Encrypted file (using fs/crypto/) */
 #define S_CASEFOLD	(1 << 15) /* Casefolded file */
 #define S_VERITY	(1 << 16) /* Verity file (using fs/verity/) */
+#define S_KERNEL_FILE	(1 << 17) /* File is in use by the kernel (eg. fs/cachefiles) */
 
 /*
  * Note that nosuid etc flags are inode-specific: setting some file-system
@@ -2342,6 +2343,8 @@ static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src,
  *			Used to detect that mark_inode_dirty() should not move
  * 			inode between dirty lists.
  *
+ * I_PINNING_FSCACHE_WB	Inode is pinning an fscache object for writeback.
+ *
  * Q: What is the difference between I_WILL_FREE and I_FREEING?
  */
 #define I_DIRTY_SYNC		(1 << 0)
@@ -2364,6 +2367,7 @@ static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src,
 #define I_CREATING		(1 << 15)
 #define I_DONTCACHE		(1 << 16)
 #define I_SYNC_QUEUED		(1 << 17)
+#define I_PINNING_FSCACHE_WB	(1 << 18)
 
 #define I_DIRTY_INODE (I_DIRTY_SYNC | I_DIRTY_DATASYNC)
 #define I_DIRTY (I_DIRTY_INODE | I_DIRTY_PAGES)
diff --git a/include/linux/fscache-cache.h b/include/linux/fscache-cache.h
index 8d39491c5f9f..a174cedf4d90 100644
--- a/include/linux/fscache-cache.h
+++ b/include/linux/fscache-cache.h
@@ -1,7 +1,7 @@
 /* SPDX-License-Identifier: GPL-2.0-or-later */
 /* General filesystem caching backing cache interface
  *
- * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
+ * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
  * Written by David Howells (dhowells@redhat.com)
  *
  * NOTE!!! See:
@@ -15,207 +15,34 @@
 #define _LINUX_FSCACHE_CACHE_H
 
 #include <linux/fscache.h>
-#include <linux/sched.h>
-#include <linux/workqueue.h>
 
-#define NR_MAXCACHES BITS_PER_LONG
-
-struct fscache_cache;
-struct fscache_cache_ops;
-struct fscache_object;
-struct fscache_operation;
-
-enum fscache_obj_ref_trace {
-	fscache_obj_get_add_to_deps,
-	fscache_obj_get_queue,
-	fscache_obj_put_alloc_fail,
-	fscache_obj_put_attach_fail,
-	fscache_obj_put_drop_obj,
-	fscache_obj_put_enq_dep,
-	fscache_obj_put_queue,
-	fscache_obj_put_work,
-	fscache_obj_ref__nr_traces
+enum fscache_cache_trace;
+enum fscache_cookie_trace;
+enum fscache_access_trace;
+
+enum fscache_cache_state {
+	FSCACHE_CACHE_IS_NOT_PRESENT,	/* No cache is present for this name */
+	FSCACHE_CACHE_IS_PREPARING,	/* A cache is preparing to come live */
+	FSCACHE_CACHE_IS_ACTIVE,	/* Attached cache is active and can be used */
+	FSCACHE_CACHE_GOT_IOERROR,	/* Attached cache stopped on I/O error */
+	FSCACHE_CACHE_IS_WITHDRAWN,	/* Attached cache is being withdrawn */
+#define NR__FSCACHE_CACHE_STATE (FSCACHE_CACHE_IS_WITHDRAWN + 1)
 };
 
 /*
- * cache tag definition
- */
-struct fscache_cache_tag {
-	struct list_head	link;
-	struct fscache_cache	*cache;		/* cache referred to by this tag */
-	unsigned long		flags;
-#define FSCACHE_TAG_RESERVED	0		/* T if tag is reserved for a cache */
-	atomic_t		usage;
-	char			name[];	/* tag name */
-};
-
-/*
- * cache definition
+ * Cache cookie.
  */
 struct fscache_cache {
 	const struct fscache_cache_ops *ops;
-	struct fscache_cache_tag *tag;		/* tag representing this cache */
-	struct kobject		*kobj;		/* system representation of this cache */
-	struct list_head	link;		/* link in list of caches */
-	size_t			max_index_size;	/* maximum size of index data */
-	char			identifier[36];	/* cache label */
-
-	/* node management */
-	struct work_struct	op_gc;		/* operation garbage collector */
-	struct list_head	object_list;	/* list of data/index objects */
-	struct list_head	op_gc_list;	/* list of ops to be deleted */
-	spinlock_t		object_list_lock;
-	spinlock_t		op_gc_list_lock;
+	struct list_head	cache_link;	/* Link in cache list */
+	void			*cache_priv;	/* Private cache data (or NULL) */
+	refcount_t		ref;
+	atomic_t		n_volumes;	/* Number of active volumes; */
+	atomic_t		n_accesses;	/* Number of in-progress accesses on the cache */
 	atomic_t		object_count;	/* no. of live objects in this cache */
-	struct fscache_object	*fsdef;		/* object for the fsdef index */
-	unsigned long		flags;
-#define FSCACHE_IOERROR		0	/* cache stopped on I/O error */
-#define FSCACHE_CACHE_WITHDRAWN	1	/* cache has been withdrawn */
-};
-
-extern wait_queue_head_t fscache_cache_cleared_wq;
-
-/*
- * operation to be applied to a cache object
- * - retrieval initiation operations are done in the context of the process
- *   that issued them, and not in an async thread pool
- */
-typedef void (*fscache_operation_release_t)(struct fscache_operation *op);
-typedef void (*fscache_operation_processor_t)(struct fscache_operation *op);
-typedef void (*fscache_operation_cancel_t)(struct fscache_operation *op);
-
-enum fscache_operation_state {
-	FSCACHE_OP_ST_BLANK,		/* Op is not yet submitted */
-	FSCACHE_OP_ST_INITIALISED,	/* Op is initialised */
-	FSCACHE_OP_ST_PENDING,		/* Op is blocked from running */
-	FSCACHE_OP_ST_IN_PROGRESS,	/* Op is in progress */
-	FSCACHE_OP_ST_COMPLETE,		/* Op is complete */
-	FSCACHE_OP_ST_CANCELLED,	/* Op has been cancelled */
-	FSCACHE_OP_ST_DEAD		/* Op is now dead */
-};
-
-struct fscache_operation {
-	struct work_struct	work;		/* record for async ops */
-	struct list_head	pend_link;	/* link in object->pending_ops */
-	struct fscache_object	*object;	/* object to be operated upon */
-
-	unsigned long		flags;
-#define FSCACHE_OP_TYPE		0x000f	/* operation type */
-#define FSCACHE_OP_ASYNC	0x0001	/* - async op, processor may sleep for disk */
-#define FSCACHE_OP_MYTHREAD	0x0002	/* - processing is done be issuing thread, not pool */
-#define FSCACHE_OP_WAITING	4	/* cleared when op is woken */
-#define FSCACHE_OP_EXCLUSIVE	5	/* exclusive op, other ops must wait */
-#define FSCACHE_OP_DEC_READ_CNT	6	/* decrement object->n_reads on destruction */
-#define FSCACHE_OP_UNUSE_COOKIE	7	/* call fscache_unuse_cookie() on completion */
-#define FSCACHE_OP_KEEP_FLAGS	0x00f0	/* flags to keep when repurposing an op */
-
-	enum fscache_operation_state state;
-	atomic_t		usage;
-	unsigned		debug_id;	/* debugging ID */
-
-	/* operation processor callback
-	 * - can be NULL if FSCACHE_OP_WAITING is going to be used to perform
-	 *   the op in a non-pool thread */
-	fscache_operation_processor_t processor;
-
-	/* Operation cancellation cleanup (optional) */
-	fscache_operation_cancel_t cancel;
-
-	/* operation releaser */
-	fscache_operation_release_t release;
-};
-
-extern atomic_t fscache_op_debug_id;
-extern void fscache_op_work_func(struct work_struct *work);
-
-extern void fscache_enqueue_operation(struct fscache_operation *);
-extern void fscache_op_complete(struct fscache_operation *, bool);
-extern void fscache_put_operation(struct fscache_operation *);
-extern void fscache_operation_init(struct fscache_cookie *,
-				   struct fscache_operation *,
-				   fscache_operation_processor_t,
-				   fscache_operation_cancel_t,
-				   fscache_operation_release_t);
-
-/*
- * data read operation
- */
-struct fscache_retrieval {
-	struct fscache_operation op;
-	struct fscache_cookie	*cookie;	/* The netfs cookie */
-	struct address_space	*mapping;	/* netfs pages */
-	fscache_rw_complete_t	end_io_func;	/* function to call on I/O completion */
-	void			*context;	/* netfs read context (pinned) */
-	struct list_head	to_do;		/* list of things to be done by the backend */
-	atomic_t		n_pages;	/* number of pages to be retrieved */
-};
-
-typedef int (*fscache_page_retrieval_func_t)(struct fscache_retrieval *op,
-					     struct page *page,
-					     gfp_t gfp);
-
-typedef int (*fscache_pages_retrieval_func_t)(struct fscache_retrieval *op,
-					      struct list_head *pages,
-					      unsigned *nr_pages,
-					      gfp_t gfp);
-
-/**
- * fscache_get_retrieval - Get an extra reference on a retrieval operation
- * @op: The retrieval operation to get a reference on
- *
- * Get an extra reference on a retrieval operation.
- */
-static inline
-struct fscache_retrieval *fscache_get_retrieval(struct fscache_retrieval *op)
-{
-	atomic_inc(&op->op.usage);
-	return op;
-}
-
-/**
- * fscache_enqueue_retrieval - Enqueue a retrieval operation for processing
- * @op: The retrieval operation affected
- *
- * Enqueue a retrieval operation for processing by the FS-Cache thread pool.
- */
-static inline void fscache_enqueue_retrieval(struct fscache_retrieval *op)
-{
-	fscache_enqueue_operation(&op->op);
-}
-
-/**
- * fscache_retrieval_complete - Record (partial) completion of a retrieval
- * @op: The retrieval operation affected
- * @n_pages: The number of pages to account for
- */
-static inline void fscache_retrieval_complete(struct fscache_retrieval *op,
-					      int n_pages)
-{
-	if (atomic_sub_return_relaxed(n_pages, &op->n_pages) <= 0)
-		fscache_op_complete(&op->op, false);
-}
-
-/**
- * fscache_put_retrieval - Drop a reference to a retrieval operation
- * @op: The retrieval operation affected
- *
- * Drop a reference to a retrieval operation.
- */
-static inline void fscache_put_retrieval(struct fscache_retrieval *op)
-{
-	fscache_put_operation(&op->op);
-}
-
-/*
- * cached page storage work item
- * - used to do three things:
- *   - batch writes to the cache
- *   - do cache writes asynchronously
- *   - defer writes until cache object lookup completion
- */
-struct fscache_storage {
-	struct fscache_operation op;
-	pgoff_t			store_limit;	/* don't write more than this */
+	unsigned int		debug_id;
+	enum fscache_cache_state state;
+	char			*name;
 };
 
 /*
@@ -225,341 +52,154 @@ struct fscache_cache_ops {
 	/* name of cache provider */
 	const char *name;
 
-	/* allocate an object record for a cookie */
-	struct fscache_object *(*alloc_object)(struct fscache_cache *cache,
-					       struct fscache_cookie *cookie);
-
-	/* look up the object for a cookie
-	 * - return -ETIMEDOUT to be requeued
-	 */
-	int (*lookup_object)(struct fscache_object *object);
-
-	/* finished looking up */
-	void (*lookup_complete)(struct fscache_object *object);
-
-	/* increment the usage count on this object (may fail if unmounting) */
-	struct fscache_object *(*grab_object)(struct fscache_object *object,
-					      enum fscache_obj_ref_trace why);
+	/* Acquire a volume */
+	void (*acquire_volume)(struct fscache_volume *volume);
 
-	/* pin an object in the cache */
-	int (*pin_object)(struct fscache_object *object);
+	/* Free the cache's data attached to a volume */
+	void (*free_volume)(struct fscache_volume *volume);
 
-	/* unpin an object in the cache */
-	void (*unpin_object)(struct fscache_object *object);
+	/* Look up a cookie in the cache */
+	bool (*lookup_cookie)(struct fscache_cookie *cookie);
 
-	/* check the consistency between the backing cache and the FS-Cache
-	 * cookie */
-	int (*check_consistency)(struct fscache_operation *op);
+	/* Withdraw an object without any cookie access counts held */
+	void (*withdraw_cookie)(struct fscache_cookie *cookie);
 
-	/* store the updated auxiliary data on an object */
-	void (*update_object)(struct fscache_object *object);
+	/* Change the size of a data object */
+	void (*resize_cookie)(struct netfs_cache_resources *cres,
+			      loff_t new_size);
 
 	/* Invalidate an object */
-	void (*invalidate_object)(struct fscache_operation *op);
-
-	/* discard the resources pinned by an object and effect retirement if
-	 * necessary */
-	void (*drop_object)(struct fscache_object *object);
-
-	/* dispose of a reference to an object */
-	void (*put_object)(struct fscache_object *object,
-			   enum fscache_obj_ref_trace why);
-
-	/* sync a cache */
-	void (*sync_cache)(struct fscache_cache *cache);
-
-	/* notification that the attributes of a non-index object (such as
-	 * i_size) have changed */
-	int (*attr_changed)(struct fscache_object *object);
-
-	/* reserve space for an object's data and associated metadata */
-	int (*reserve_space)(struct fscache_object *object, loff_t i_size);
-
-	/* request a backing block for a page be read or allocated in the
-	 * cache */
-	fscache_page_retrieval_func_t read_or_alloc_page;
-
-	/* request backing blocks for a list of pages be read or allocated in
-	 * the cache */
-	fscache_pages_retrieval_func_t read_or_alloc_pages;
-
-	/* request a backing block for a page be allocated in the cache so that
-	 * it can be written directly */
-	fscache_page_retrieval_func_t allocate_page;
-
-	/* request backing blocks for pages be allocated in the cache so that
-	 * they can be written directly */
-	fscache_pages_retrieval_func_t allocate_pages;
-
-	/* write a page to its backing block in the cache */
-	int (*write_page)(struct fscache_storage *op, struct page *page);
-
-	/* detach backing block from a page (optional)
-	 * - must release the cookie lock before returning
-	 * - may sleep
-	 */
-	void (*uncache_page)(struct fscache_object *object,
-			     struct page *page);
-
-	/* dissociate a cache from all the pages it was backing */
-	void (*dissociate_pages)(struct fscache_cache *cache);
+	bool (*invalidate_cookie)(struct fscache_cookie *cookie);
 
-	/* Begin a read operation for the netfs lib */
-	int (*begin_read_operation)(struct netfs_read_request *rreq,
-				    struct fscache_retrieval *op);
-};
-
-extern struct fscache_cookie fscache_fsdef_index;
+	/* Begin an operation for the netfs lib */
+	bool (*begin_operation)(struct netfs_cache_resources *cres,
+				enum fscache_want_state want_state);
 
-/*
- * Event list for fscache_object::{event_mask,events}
- */
-enum {
-	FSCACHE_OBJECT_EV_NEW_CHILD,	/* T if object has a new child */
-	FSCACHE_OBJECT_EV_PARENT_READY,	/* T if object's parent is ready */
-	FSCACHE_OBJECT_EV_UPDATE,	/* T if object should be updated */
-	FSCACHE_OBJECT_EV_INVALIDATE,	/* T if cache requested object invalidation */
-	FSCACHE_OBJECT_EV_CLEARED,	/* T if accessors all gone */
-	FSCACHE_OBJECT_EV_ERROR,	/* T if fatal error occurred during processing */
-	FSCACHE_OBJECT_EV_KILL,		/* T if netfs relinquished or cache withdrew object */
-	NR_FSCACHE_OBJECT_EVENTS
-};
-
-#define FSCACHE_OBJECT_EVENTS_MASK ((1UL << NR_FSCACHE_OBJECT_EVENTS) - 1)
-
-/*
- * States for object state machine.
- */
-struct fscache_transition {
-	unsigned long events;
-	const struct fscache_state *transit_to;
+	/* Prepare to write to a live cache object */
+	void (*prepare_to_write)(struct fscache_cookie *cookie);
 };
 
-struct fscache_state {
-	char name[24];
-	char short_name[8];
-	const struct fscache_state *(*work)(struct fscache_object *object,
-					    int event);
-	const struct fscache_transition transitions[];
-};
+extern struct workqueue_struct *fscache_wq;
+extern wait_queue_head_t fscache_clearance_waiters;
 
 /*
- * on-disk cache file or index handle
+ * out-of-line cache backend functions
  */
-struct fscache_object {
-	const struct fscache_state *state;	/* Object state machine state */
-	const struct fscache_transition *oob_table; /* OOB state transition table */
-	int			debug_id;	/* debugging ID */
-	int			n_children;	/* number of child objects */
-	int			n_ops;		/* number of extant ops on object */
-	int			n_obj_ops;	/* number of object ops outstanding on object */
-	int			n_in_progress;	/* number of ops in progress */
-	int			n_exclusive;	/* number of exclusive ops queued or in progress */
-	atomic_t		n_reads;	/* number of read ops in progress */
-	spinlock_t		lock;		/* state and operations lock */
-
-	unsigned long		lookup_jif;	/* time at which lookup started */
-	unsigned long		oob_event_mask;	/* OOB events this object is interested in */
-	unsigned long		event_mask;	/* events this object is interested in */
-	unsigned long		events;		/* events to be processed by this object
-						 * (order is important - using fls) */
-
-	unsigned long		flags;
-#define FSCACHE_OBJECT_LOCK		0	/* T if object is busy being processed */
-#define FSCACHE_OBJECT_PENDING_WRITE	1	/* T if object has pending write */
-#define FSCACHE_OBJECT_WAITING		2	/* T if object is waiting on its parent */
-#define FSCACHE_OBJECT_IS_LIVE		3	/* T if object is not withdrawn or relinquished */
-#define FSCACHE_OBJECT_IS_LOOKED_UP	4	/* T if object has been looked up */
-#define FSCACHE_OBJECT_IS_AVAILABLE	5	/* T if object has become active */
-#define FSCACHE_OBJECT_RETIRED		6	/* T if object was retired on relinquishment */
-#define FSCACHE_OBJECT_KILLED_BY_CACHE	7	/* T if object was killed by the cache */
-#define FSCACHE_OBJECT_RUN_AFTER_DEAD	8	/* T if object has been dispatched after death */
-
-	struct list_head	cache_link;	/* link in cache->object_list */
-	struct hlist_node	cookie_link;	/* link in cookie->backing_objects */
-	struct fscache_cache	*cache;		/* cache that supplied this object */
-	struct fscache_cookie	*cookie;	/* netfs's file/index object */
-	struct fscache_object	*parent;	/* parent object */
-	struct work_struct	work;		/* attention scheduling record */
-	struct list_head	dependents;	/* FIFO of dependent objects */
-	struct list_head	dep_link;	/* link in parent's dependents list */
-	struct list_head	pending_ops;	/* unstarted operations on this object */
-	pgoff_t			store_limit;	/* current storage limit */
-	loff_t			store_limit_l;	/* current storage limit */
-};
-
-extern void fscache_object_init(struct fscache_object *, struct fscache_cookie *,
-				struct fscache_cache *);
-extern void fscache_object_destroy(struct fscache_object *);
-
-extern void fscache_object_lookup_negative(struct fscache_object *object);
-extern void fscache_obtained_object(struct fscache_object *object);
-
-static inline bool fscache_object_is_live(struct fscache_object *object)
-{
-	return test_bit(FSCACHE_OBJECT_IS_LIVE, &object->flags);
-}
-
-static inline bool fscache_object_is_dying(struct fscache_object *object)
-{
-	return !fscache_object_is_live(object);
-}
-
-static inline bool fscache_object_is_available(struct fscache_object *object)
-{
-	return test_bit(FSCACHE_OBJECT_IS_AVAILABLE, &object->flags);
-}
+extern struct rw_semaphore fscache_addremove_sem;
+extern struct fscache_cache *fscache_acquire_cache(const char *name);
+extern void fscache_relinquish_cache(struct fscache_cache *cache);
+extern int fscache_add_cache(struct fscache_cache *cache,
+			     const struct fscache_cache_ops *ops,
+			     void *cache_priv);
+extern void fscache_withdraw_cache(struct fscache_cache *cache);
+extern void fscache_withdraw_volume(struct fscache_volume *volume);
+extern void fscache_withdraw_cookie(struct fscache_cookie *cookie);
 
-static inline bool fscache_cache_is_broken(struct fscache_object *object)
-{
-	return test_bit(FSCACHE_IOERROR, &object->cache->flags);
-}
+extern void fscache_io_error(struct fscache_cache *cache);
 
-static inline bool fscache_object_is_active(struct fscache_object *object)
-{
-	return fscache_object_is_available(object) &&
-		fscache_object_is_live(object) &&
-		!fscache_cache_is_broken(object);
-}
+extern void fscache_end_volume_access(struct fscache_volume *volume,
+				      struct fscache_cookie *cookie,
+				      enum fscache_access_trace why);
+
+extern struct fscache_cookie *fscache_get_cookie(struct fscache_cookie *cookie,
+						 enum fscache_cookie_trace where);
+extern void fscache_put_cookie(struct fscache_cookie *cookie,
+			       enum fscache_cookie_trace where);
+extern void fscache_end_cookie_access(struct fscache_cookie *cookie,
+				      enum fscache_access_trace why);
+extern void fscache_cookie_lookup_negative(struct fscache_cookie *cookie);
+extern void fscache_resume_after_invalidation(struct fscache_cookie *cookie);
+extern void fscache_caching_failed(struct fscache_cookie *cookie);
+extern bool fscache_wait_for_operation(struct netfs_cache_resources *cred,
+				       enum fscache_want_state state);
 
 /**
- * fscache_object_destroyed - Note destruction of an object in a cache
- * @cache: The cache from which the object came
+ * fscache_cookie_state - Read the state of a cookie
+ * @cookie: The cookie to query
  *
- * Note the destruction and deallocation of an object record in a cache.
+ * Get the state of a cookie, imposing an ordering between the cookie contents
+ * and the state value.  Paired with fscache_set_cookie_state().
  */
-static inline void fscache_object_destroyed(struct fscache_cache *cache)
+static inline
+enum fscache_cookie_state fscache_cookie_state(struct fscache_cookie *cookie)
 {
-	if (atomic_dec_and_test(&cache->object_count))
-		wake_up_all(&fscache_cache_cleared_wq);
+	return smp_load_acquire(&cookie->state);
 }
 
 /**
- * fscache_object_lookup_error - Note an object encountered an error
- * @object: The object on which the error was encountered
+ * fscache_get_key - Get a pointer to the cookie key
+ * @cookie: The cookie to query
  *
- * Note that an object encountered a fatal error (usually an I/O error) and
- * that it should be withdrawn as soon as possible.
+ * Return a pointer to the where a cookie's key is stored.
  */
-static inline void fscache_object_lookup_error(struct fscache_object *object)
+static inline void *fscache_get_key(struct fscache_cookie *cookie)
 {
-	set_bit(FSCACHE_OBJECT_EV_ERROR, &object->events);
+	if (cookie->key_len <= sizeof(cookie->inline_key))
+		return cookie->inline_key;
+	else
+		return cookie->key;
 }
 
-/**
- * fscache_set_store_limit - Set the maximum size to be stored in an object
- * @object: The object to set the maximum on
- * @i_size: The limit to set in bytes
- *
- * Set the maximum size an object is permitted to reach, implying the highest
- * byte that may be written.  Intended to be called by the attr_changed() op.
- *
- * See Documentation/filesystems/caching/backend-api.rst for a complete
- * description.
- */
-static inline
-void fscache_set_store_limit(struct fscache_object *object, loff_t i_size)
+static inline struct fscache_cookie *fscache_cres_cookie(struct netfs_cache_resources *cres)
 {
-	object->store_limit_l = i_size;
-	object->store_limit = i_size >> PAGE_SHIFT;
-	if (i_size & ~PAGE_MASK)
-		object->store_limit++;
+	return cres->cache_priv;
 }
 
 /**
- * fscache_end_io - End a retrieval operation on a page
- * @op: The FS-Cache operation covering the retrieval
- * @page: The page that was to be fetched
- * @error: The error code (0 if successful)
+ * fscache_count_object - Tell fscache that an object has been added
+ * @cache: The cache to account to
  *
- * Note the end of an operation to retrieve a page, as covered by a particular
- * operation record.
+ * Tell fscache that an object has been added to the cache.  This prevents the
+ * cache from tearing down the cache structure until the object is uncounted.
  */
-static inline void fscache_end_io(struct fscache_retrieval *op,
-				  struct page *page, int error)
+static inline void fscache_count_object(struct fscache_cache *cache)
 {
-	op->end_io_func(page, op->context, error);
-}
-
-static inline void __fscache_use_cookie(struct fscache_cookie *cookie)
-{
-	atomic_inc(&cookie->n_active);
+	atomic_inc(&cache->object_count);
 }
 
 /**
- * fscache_use_cookie - Request usage of cookie attached to an object
- * @object: Object description
- * 
- * Request usage of the cookie attached to an object.  NULL is returned if the
- * relinquishment had reduced the cookie usage count to 0.
+ * fscache_uncount_object - Tell fscache that an object has been removed
+ * @cache: The cache to account to
+ *
+ * Tell fscache that an object has been removed from the cache and will no
+ * longer be accessed.  After this point, the cache cookie may be destroyed.
  */
-static inline bool fscache_use_cookie(struct fscache_object *object)
-{
-	struct fscache_cookie *cookie = object->cookie;
-	return atomic_inc_not_zero(&cookie->n_active) != 0;
-}
-
-static inline bool __fscache_unuse_cookie(struct fscache_cookie *cookie)
-{
-	return atomic_dec_and_test(&cookie->n_active);
-}
-
-static inline void __fscache_wake_unused_cookie(struct fscache_cookie *cookie)
+static inline void fscache_uncount_object(struct fscache_cache *cache)
 {
-	wake_up_var(&cookie->n_active);
+	if (atomic_dec_and_test(&cache->object_count))
+		wake_up_all(&fscache_clearance_waiters);
 }
 
 /**
- * fscache_unuse_cookie - Cease usage of cookie attached to an object
- * @object: Object description
- * 
- * Cease usage of the cookie attached to an object.  When the users count
- * reaches zero then the cookie relinquishment will be permitted to proceed.
- */
-static inline void fscache_unuse_cookie(struct fscache_object *object)
-{
-	struct fscache_cookie *cookie = object->cookie;
-	if (__fscache_unuse_cookie(cookie))
-		__fscache_wake_unused_cookie(cookie);
-}
-
-/*
- * out-of-line cache backend functions
- */
-extern __printf(3, 4)
-void fscache_init_cache(struct fscache_cache *cache,
-			const struct fscache_cache_ops *ops,
-			const char *idfmt, ...);
-
-extern int fscache_add_cache(struct fscache_cache *cache,
-			     struct fscache_object *fsdef,
-			     const char *tagname);
-extern void fscache_withdraw_cache(struct fscache_cache *cache);
-
-extern void fscache_io_error(struct fscache_cache *cache);
-
-extern void fscache_mark_page_cached(struct fscache_retrieval *op,
-				     struct page *page);
-
-extern void fscache_mark_pages_cached(struct fscache_retrieval *op,
-				      struct pagevec *pagevec);
-
-extern bool fscache_object_sleep_till_congested(signed long *timeoutp);
-
-extern enum fscache_checkaux fscache_check_aux(struct fscache_object *object,
-					       const void *data,
-					       uint16_t datalen,
-					       loff_t object_size);
-
-extern void fscache_object_retrying_stale(struct fscache_object *object);
-
-enum fscache_why_object_killed {
-	FSCACHE_OBJECT_IS_STALE,
-	FSCACHE_OBJECT_NO_SPACE,
-	FSCACHE_OBJECT_WAS_RETIRED,
-	FSCACHE_OBJECT_WAS_CULLED,
-};
-extern void fscache_object_mark_killed(struct fscache_object *object,
-				       enum fscache_why_object_killed why);
+ * fscache_wait_for_objects - Wait for all objects to be withdrawn
+ * @cache: The cache to query
+ *
+ * Wait for all extant objects in a cache to finish being withdrawn
+ * and go away.
+ */
+static inline void fscache_wait_for_objects(struct fscache_cache *cache)
+{
+	wait_event(fscache_clearance_waiters,
+		   atomic_read(&cache->object_count) == 0);
+}
+
+#ifdef CONFIG_FSCACHE_STATS
+extern atomic_t fscache_n_read;
+extern atomic_t fscache_n_write;
+extern atomic_t fscache_n_no_write_space;
+extern atomic_t fscache_n_no_create_space;
+extern atomic_t fscache_n_culled;
+#define fscache_count_read() atomic_inc(&fscache_n_read)
+#define fscache_count_write() atomic_inc(&fscache_n_write)
+#define fscache_count_no_write_space() atomic_inc(&fscache_n_no_write_space)
+#define fscache_count_no_create_space() atomic_inc(&fscache_n_no_create_space)
+#define fscache_count_culled() atomic_inc(&fscache_n_culled)
+#else
+#define fscache_count_read() do {} while(0)
+#define fscache_count_write() do {} while(0)
+#define fscache_count_no_write_space() do {} while(0)
+#define fscache_count_no_create_space() do {} while(0)
+#define fscache_count_culled() do {} while(0)
+#endif
 
 #endif /* _LINUX_FSCACHE_CACHE_H */
diff --git a/include/linux/fscache.h b/include/linux/fscache.h
index 3b2282c157f7..ede50406bcb0 100644
--- a/include/linux/fscache.h
+++ b/include/linux/fscache.h
@@ -1,7 +1,7 @@
 /* SPDX-License-Identifier: GPL-2.0-or-later */
 /* General filesystem caching interface
  *
- * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
+ * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
  * Written by David Howells (dhowells@redhat.com)
  *
  * NOTE!!! See:
@@ -15,146 +15,126 @@
 #define _LINUX_FSCACHE_H
 
 #include <linux/fs.h>
-#include <linux/list.h>
-#include <linux/pagemap.h>
-#include <linux/pagevec.h>
-#include <linux/list_bl.h>
 #include <linux/netfs.h>
+#include <linux/writeback.h>
 
 #if defined(CONFIG_FSCACHE) || defined(CONFIG_FSCACHE_MODULE)
+#define __fscache_available (1)
 #define fscache_available() (1)
+#define fscache_volume_valid(volume) (volume)
 #define fscache_cookie_valid(cookie) (cookie)
+#define fscache_resources_valid(cres) ((cres)->cache_priv)
+#define fscache_cookie_enabled(cookie) (cookie && !test_bit(FSCACHE_COOKIE_DISABLED, &cookie->flags))
 #else
+#define __fscache_available (0)
 #define fscache_available() (0)
+#define fscache_volume_valid(volume) (0)
 #define fscache_cookie_valid(cookie) (0)
+#define fscache_resources_valid(cres) (false)
+#define fscache_cookie_enabled(cookie) (0)
 #endif
 
+struct fscache_cookie;
 
-/* pattern used to fill dead space in an index entry */
-#define FSCACHE_INDEX_DEADFILL_PATTERN 0x79
+#define FSCACHE_ADV_SINGLE_CHUNK	0x01 /* The object is a single chunk of data */
+#define FSCACHE_ADV_WRITE_CACHE		0x00 /* Do cache if written to locally */
+#define FSCACHE_ADV_WRITE_NOCACHE	0x02 /* Don't cache if written to locally */
 
-struct pagevec;
-struct fscache_cache_tag;
-struct fscache_cookie;
-struct fscache_netfs;
-struct netfs_read_request;
-
-typedef void (*fscache_rw_complete_t)(struct page *page,
-				      void *context,
-				      int error);
-
-/* result of index entry consultation */
-enum fscache_checkaux {
-	FSCACHE_CHECKAUX_OKAY,		/* entry okay as is */
-	FSCACHE_CHECKAUX_NEEDS_UPDATE,	/* entry requires update */
-	FSCACHE_CHECKAUX_OBSOLETE,	/* entry requires deletion */
+#define FSCACHE_INVAL_DIO_WRITE		0x01 /* Invalidate due to DIO write */
+
+enum fscache_want_state {
+	FSCACHE_WANT_PARAMS,
+	FSCACHE_WANT_WRITE,
+	FSCACHE_WANT_READ,
 };
 
 /*
- * fscache cookie definition
- */
-struct fscache_cookie_def {
-	/* name of cookie type */
-	char name[16];
-
-	/* cookie type */
-	uint8_t type;
-#define FSCACHE_COOKIE_TYPE_INDEX	0
-#define FSCACHE_COOKIE_TYPE_DATAFILE	1
-
-	/* select the cache into which to insert an entry in this index
-	 * - optional
-	 * - should return a cache identifier or NULL to cause the cache to be
-	 *   inherited from the parent if possible or the first cache picked
-	 *   for a non-index file if not
-	 */
-	struct fscache_cache_tag *(*select_cache)(
-		const void *parent_netfs_data,
-		const void *cookie_netfs_data);
-
-	/* consult the netfs about the state of an object
-	 * - this function can be absent if the index carries no state data
-	 * - the netfs data from the cookie being used as the target is
-	 *   presented, as is the auxiliary data and the object size
-	 */
-	enum fscache_checkaux (*check_aux)(void *cookie_netfs_data,
-					   const void *data,
-					   uint16_t datalen,
-					   loff_t object_size);
-
-	/* get an extra reference on a read context
-	 * - this function can be absent if the completion function doesn't
-	 *   require a context
-	 */
-	void (*get_context)(void *cookie_netfs_data, void *context);
-
-	/* release an extra reference on a read context
-	 * - this function can be absent if the completion function doesn't
-	 *   require a context
-	 */
-	void (*put_context)(void *cookie_netfs_data, void *context);
-
-	/* indicate page that now have cache metadata retained
-	 * - this function should mark the specified page as now being cached
-	 * - the page will have been marked with PG_fscache before this is
-	 *   called, so this is optional
-	 */
-	void (*mark_page_cached)(void *cookie_netfs_data,
-				 struct address_space *mapping,
-				 struct page *page);
-};
+ * Data object state.
+ */
+enum fscache_cookie_state {
+	FSCACHE_COOKIE_STATE_QUIESCENT,		/* The cookie is uncached */
+	FSCACHE_COOKIE_STATE_LOOKING_UP,	/* The cache object is being looked up */
+	FSCACHE_COOKIE_STATE_CREATING,		/* The cache object is being created */
+	FSCACHE_COOKIE_STATE_ACTIVE,		/* The cache is active, readable and writable */
+	FSCACHE_COOKIE_STATE_INVALIDATING,	/* The cache is being invalidated */
+	FSCACHE_COOKIE_STATE_FAILED,		/* The cache failed, withdraw to clear */
+	FSCACHE_COOKIE_STATE_LRU_DISCARDING,	/* The cookie is being discarded by the LRU */
+	FSCACHE_COOKIE_STATE_WITHDRAWING,	/* The cookie is being withdrawn */
+	FSCACHE_COOKIE_STATE_RELINQUISHING,	/* The cookie is being relinquished */
+	FSCACHE_COOKIE_STATE_DROPPED,		/* The cookie has been dropped */
+#define FSCACHE_COOKIE_STATE__NR (FSCACHE_COOKIE_STATE_DROPPED + 1)
+} __attribute__((mode(byte)));
 
 /*
- * fscache cached network filesystem type
- * - name, version and ops must be filled in before registration
- * - all other fields will be set during registration
+ * Volume representation cookie.
  */
-struct fscache_netfs {
-	uint32_t			version;	/* indexing version */
-	const char			*name;		/* filesystem name */
-	struct fscache_cookie		*primary_index;
+struct fscache_volume {
+	refcount_t			ref;
+	atomic_t			n_cookies;	/* Number of data cookies in volume */
+	atomic_t			n_accesses;	/* Number of cache accesses in progress */
+	unsigned int			debug_id;
+	unsigned int			key_hash;	/* Hash of key string */
+	char				*key;		/* Volume ID, eg. "afs@example.com@1234" */
+	struct list_head		proc_link;	/* Link in /proc/fs/fscache/volumes */
+	struct hlist_bl_node		hash_link;	/* Link in hash table */
+	struct work_struct		work;
+	struct fscache_cache		*cache;		/* The cache in which this resides */
+	void				*cache_priv;	/* Cache private data */
+	spinlock_t			lock;
+	unsigned long			flags;
+#define FSCACHE_VOLUME_RELINQUISHED	0	/* Volume is being cleaned up */
+#define FSCACHE_VOLUME_INVALIDATE	1	/* Volume was invalidated */
+#define FSCACHE_VOLUME_COLLIDED_WITH	2	/* Volume was collided with */
+#define FSCACHE_VOLUME_ACQUIRE_PENDING	3	/* Volume is waiting to complete acquisition */
+#define FSCACHE_VOLUME_CREATING		4	/* Volume is being created on disk */
+	u8				coherency_len;	/* Length of the coherency data */
+	u8				coherency[];	/* Coherency data */
 };
 
 /*
- * data file or index object cookie
+ * Data file representation cookie.
  * - a file will only appear in one cache
  * - a request to cache a file may or may not be honoured, subject to
  *   constraints such as disk space
  * - indices are created on disk just-in-time
  */
 struct fscache_cookie {
-	refcount_t			ref;		/* number of users of this cookie */
-	atomic_t			n_children;	/* number of children of this cookie */
-	atomic_t			n_active;	/* number of active users of netfs ptrs */
+	refcount_t			ref;
+	atomic_t			n_active;	/* number of active users of cookie */
+	atomic_t			n_accesses;	/* Number of cache accesses in progress */
 	unsigned int			debug_id;
+	unsigned int			inval_counter;	/* Number of invalidations made */
 	spinlock_t			lock;
-	spinlock_t			stores_lock;	/* lock on page store tree */
-	struct hlist_head		backing_objects; /* object(s) backing this file/index */
-	const struct fscache_cookie_def	*def;		/* definition */
-	struct fscache_cookie		*parent;	/* parent of this entry */
+	struct fscache_volume		*volume;	/* Parent volume of this file. */
+	void				*cache_priv;	/* Cache-side representation */
 	struct hlist_bl_node		hash_link;	/* Link in hash table */
 	struct list_head		proc_link;	/* Link in proc list */
-	void				*netfs_data;	/* back pointer to netfs */
-	struct radix_tree_root		stores;		/* pages to be stored on this cookie */
-#define FSCACHE_COOKIE_PENDING_TAG	0		/* pages tag: pending write to cache */
-#define FSCACHE_COOKIE_STORING_TAG	1		/* pages tag: writing to cache */
-
+	struct list_head		commit_link;	/* Link in commit queue */
+	struct work_struct		work;		/* Commit/relinq/withdraw work */
+	loff_t				object_size;	/* Size of the netfs object */
+	unsigned long			unused_at;	/* Time at which unused (jiffies) */
 	unsigned long			flags;
-#define FSCACHE_COOKIE_LOOKING_UP	0	/* T if non-index cookie being looked up still */
-#define FSCACHE_COOKIE_NO_DATA_YET	1	/* T if new object with no cached data yet */
-#define FSCACHE_COOKIE_UNAVAILABLE	2	/* T if cookie is unavailable (error, etc) */
-#define FSCACHE_COOKIE_INVALIDATING	3	/* T if cookie is being invalidated */
-#define FSCACHE_COOKIE_RELINQUISHED	4	/* T if cookie has been relinquished */
-#define FSCACHE_COOKIE_ENABLED		5	/* T if cookie is enabled */
-#define FSCACHE_COOKIE_ENABLEMENT_LOCK	6	/* T if cookie is being en/disabled */
-#define FSCACHE_COOKIE_AUX_UPDATED	8	/* T if the auxiliary data was updated */
-#define FSCACHE_COOKIE_ACQUIRED		9	/* T if cookie is in use */
-#define FSCACHE_COOKIE_RELINQUISHING	10	/* T if cookie is being relinquished */
-
-	u8				type;		/* Type of object */
+#define FSCACHE_COOKIE_RELINQUISHED	0		/* T if cookie has been relinquished */
+#define FSCACHE_COOKIE_RETIRED		1		/* T if this cookie has retired on relinq */
+#define FSCACHE_COOKIE_IS_CACHING	2		/* T if this cookie is cached */
+#define FSCACHE_COOKIE_NO_DATA_TO_READ	3		/* T if this cookie has nothing to read */
+#define FSCACHE_COOKIE_NEEDS_UPDATE	4		/* T if attrs have been updated */
+#define FSCACHE_COOKIE_HAS_BEEN_CACHED	5		/* T if cookie needs withdraw-on-relinq */
+#define FSCACHE_COOKIE_DISABLED		6		/* T if cookie has been disabled */
+#define FSCACHE_COOKIE_LOCAL_WRITE	7		/* T if cookie has been modified locally */
+#define FSCACHE_COOKIE_NO_ACCESS_WAKE	8		/* T if no wake when n_accesses goes 0 */
+#define FSCACHE_COOKIE_DO_RELINQUISH	9		/* T if this cookie needs relinquishment */
+#define FSCACHE_COOKIE_DO_WITHDRAW	10		/* T if this cookie needs withdrawing */
+#define FSCACHE_COOKIE_DO_LRU_DISCARD	11		/* T if this cookie needs LRU discard */
+#define FSCACHE_COOKIE_DO_PREP_TO_WRITE	12		/* T if cookie needs write preparation */
+#define FSCACHE_COOKIE_HAVE_DATA	13		/* T if this cookie has data stored */
+#define FSCACHE_COOKIE_IS_HASHED	14		/* T if this cookie is hashed */
+
+	enum fscache_cookie_state	state;
+	u8				advice;		/* FSCACHE_ADV_* */
 	u8				key_len;	/* Length of index key */
 	u8				aux_len;	/* Length of auxiliary data */
-	u32				key_hash;	/* Hash of parent, type, key, len */
+	u32				key_hash;	/* Hash of volume, key, len */
 	union {
 		void			*key;		/* Index key */
 		u8			inline_key[16];	/* - If the key is short enough */
@@ -165,11 +145,6 @@ struct fscache_cookie {
 	};
 };
 
-static inline bool fscache_cookie_enabled(struct fscache_cookie *cookie)
-{
-	return fscache_cookie_valid(cookie) && test_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
-}
-
 /*
  * slow-path functions for when there is actually caching available, and the
  * netfs does actually have a valid token
@@ -177,699 +152,523 @@ static inline bool fscache_cookie_enabled(struct fscache_cookie *cookie)
  * - these are undefined symbols when FS-Cache is not configured and the
  *   optimiser takes care of not using them
  */
-extern int __fscache_register_netfs(struct fscache_netfs *);
-extern void __fscache_unregister_netfs(struct fscache_netfs *);
-extern struct fscache_cache_tag *__fscache_lookup_cache_tag(const char *);
-extern void __fscache_release_cache_tag(struct fscache_cache_tag *);
+extern struct fscache_volume *__fscache_acquire_volume(const char *, const char *,
+						       const void *, size_t);
+extern void __fscache_relinquish_volume(struct fscache_volume *, const void *, bool);
 
 extern struct fscache_cookie *__fscache_acquire_cookie(
-	struct fscache_cookie *,
-	const struct fscache_cookie_def *,
+	struct fscache_volume *,
+	u8,
 	const void *, size_t,
 	const void *, size_t,
-	void *, loff_t, bool);
-extern void __fscache_relinquish_cookie(struct fscache_cookie *, const void *, bool);
-extern int __fscache_check_consistency(struct fscache_cookie *, const void *);
-extern void __fscache_update_cookie(struct fscache_cookie *, const void *);
-extern int __fscache_attr_changed(struct fscache_cookie *);
-extern void __fscache_invalidate(struct fscache_cookie *);
-extern void __fscache_wait_on_invalidate(struct fscache_cookie *);
-
-#ifdef FSCACHE_USE_NEW_IO_API
-extern int __fscache_begin_read_operation(struct netfs_read_request *, struct fscache_cookie *);
-#else
-extern int __fscache_read_or_alloc_page(struct fscache_cookie *,
-					struct page *,
-					fscache_rw_complete_t,
-					void *,
-					gfp_t);
-extern int __fscache_read_or_alloc_pages(struct fscache_cookie *,
-					 struct address_space *,
-					 struct list_head *,
-					 unsigned *,
-					 fscache_rw_complete_t,
-					 void *,
-					 gfp_t);
-extern int __fscache_alloc_page(struct fscache_cookie *, struct page *, gfp_t);
-extern int __fscache_write_page(struct fscache_cookie *, struct page *, loff_t, gfp_t);
-extern void __fscache_uncache_page(struct fscache_cookie *, struct page *);
-extern bool __fscache_check_page_write(struct fscache_cookie *, struct page *);
-extern void __fscache_wait_on_page_write(struct fscache_cookie *, struct page *);
-extern bool __fscache_maybe_release_page(struct fscache_cookie *, struct page *,
-					 gfp_t);
-extern void __fscache_uncache_all_inode_pages(struct fscache_cookie *,
-					      struct inode *);
-extern void __fscache_readpages_cancel(struct fscache_cookie *cookie,
-				       struct list_head *pages);
-#endif /* FSCACHE_USE_NEW_IO_API */
-
-extern void __fscache_disable_cookie(struct fscache_cookie *, const void *, bool);
-extern void __fscache_enable_cookie(struct fscache_cookie *, const void *, loff_t,
-				    bool (*)(void *), void *);
+	loff_t);
+extern void __fscache_use_cookie(struct fscache_cookie *, bool);
+extern void __fscache_unuse_cookie(struct fscache_cookie *, const void *, const loff_t *);
+extern void __fscache_relinquish_cookie(struct fscache_cookie *, bool);
+extern void __fscache_resize_cookie(struct fscache_cookie *, loff_t);
+extern void __fscache_invalidate(struct fscache_cookie *, const void *, loff_t, unsigned int);
+extern int __fscache_begin_read_operation(struct netfs_cache_resources *, struct fscache_cookie *);
+extern int __fscache_begin_write_operation(struct netfs_cache_resources *, struct fscache_cookie *);
+
+extern void __fscache_write_to_cache(struct fscache_cookie *, struct address_space *,
+				     loff_t, size_t, loff_t, netfs_io_terminated_t, void *,
+				     bool);
+extern void __fscache_clear_page_bits(struct address_space *, loff_t, size_t);
 
 /**
- * fscache_register_netfs - Register a filesystem as desiring caching services
- * @netfs: The description of the filesystem
+ * fscache_acquire_volume - Register a volume as desiring caching services
+ * @volume_key: An identification string for the volume
+ * @cache_name: The name of the cache to use (or NULL for the default)
+ * @coherency_data: Piece of arbitrary coherency data to check (or NULL)
+ * @coherency_len: The size of the coherency data
  *
- * Register a filesystem as desiring caching services if they're available.
+ * Register a volume as desiring caching services if they're available.  The
+ * caller must provide an identifier for the volume and may also indicate which
+ * cache it should be in.  If a preexisting volume entry is found in the cache,
+ * the coherency data must match otherwise the entry will be invalidated.
  *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
+ * Returns a cookie pointer on success, -ENOMEM if out of memory or -EBUSY if a
+ * cache volume of that name is already acquired.  Note that "NULL" is a valid
+ * cookie pointer and can be returned if caching is refused.
  */
 static inline
-int fscache_register_netfs(struct fscache_netfs *netfs)
+struct fscache_volume *fscache_acquire_volume(const char *volume_key,
+					      const char *cache_name,
+					      const void *coherency_data,
+					      size_t coherency_len)
 {
-	if (fscache_available())
-		return __fscache_register_netfs(netfs);
-	else
-		return 0;
+	if (!fscache_available())
+		return NULL;
+	return __fscache_acquire_volume(volume_key, cache_name,
+					coherency_data, coherency_len);
 }
 
 /**
- * fscache_unregister_netfs - Indicate that a filesystem no longer desires
- * caching services
- * @netfs: The description of the filesystem
+ * fscache_relinquish_volume - Cease caching a volume
+ * @volume: The volume cookie
+ * @coherency_data: Piece of arbitrary coherency data to set (or NULL)
+ * @invalidate: True if the volume should be invalidated
  *
- * Indicate that a filesystem no longer desires caching services for the
- * moment.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
+ * Indicate that a filesystem no longer desires caching services for a volume.
+ * The caller must have relinquished all file cookies prior to calling this.
+ * The stored coherency data is updated.
  */
 static inline
-void fscache_unregister_netfs(struct fscache_netfs *netfs)
+void fscache_relinquish_volume(struct fscache_volume *volume,
+			       const void *coherency_data,
+			       bool invalidate)
 {
-	if (fscache_available())
-		__fscache_unregister_netfs(netfs);
+	if (fscache_volume_valid(volume))
+		__fscache_relinquish_volume(volume, coherency_data, invalidate);
 }
 
 /**
- * fscache_lookup_cache_tag - Look up a cache tag
- * @name: The name of the tag to search for
+ * fscache_acquire_cookie - Acquire a cookie to represent a cache object
+ * @volume: The volume in which to locate/create this cookie
+ * @advice: Advice flags (FSCACHE_COOKIE_ADV_*)
+ * @index_key: The index key for this cookie
+ * @index_key_len: Size of the index key
+ * @aux_data: The auxiliary data for the cookie (may be NULL)
+ * @aux_data_len: Size of the auxiliary data buffer
+ * @object_size: The initial size of object
  *
- * Acquire a specific cache referral tag that can be used to select a specific
- * cache in which to cache an index.
+ * Acquire a cookie to represent a data file within the given cache volume.
  *
  * See Documentation/filesystems/caching/netfs-api.rst for a complete
  * description.
  */
 static inline
-struct fscache_cache_tag *fscache_lookup_cache_tag(const char *name)
+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)
 {
-	if (fscache_available())
-		return __fscache_lookup_cache_tag(name);
-	else
+	if (!fscache_volume_valid(volume))
 		return NULL;
+	return __fscache_acquire_cookie(volume, advice,
+					index_key, index_key_len,
+					aux_data, aux_data_len,
+					object_size);
 }
 
 /**
- * fscache_release_cache_tag - Release a cache tag
- * @tag: The tag to release
- *
- * Release a reference to a cache referral tag previously looked up.
+ * fscache_use_cookie - Request usage of cookie attached to an object
+ * @object: Object description
+ * @will_modify: If cache is expected to be modified locally
  *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
+ * Request usage of the cookie attached to an object.  The caller should tell
+ * the cache if the object's contents are about to be modified locally and then
+ * the cache can apply the policy that has been set to handle this case.
  */
-static inline
-void fscache_release_cache_tag(struct fscache_cache_tag *tag)
+static inline void fscache_use_cookie(struct fscache_cookie *cookie,
+				      bool will_modify)
 {
-	if (fscache_available())
-		__fscache_release_cache_tag(tag);
+	if (fscache_cookie_valid(cookie))
+		__fscache_use_cookie(cookie, will_modify);
 }
 
 /**
- * fscache_acquire_cookie - Acquire a cookie to represent a cache object
- * @parent: The cookie that's to be the parent of this one
- * @def: A description of the cache object, including callback operations
- * @index_key: The index key for this cookie
- * @index_key_len: Size of the index key
- * @aux_data: The auxiliary data for the cookie (may be NULL)
- * @aux_data_len: Size of the auxiliary data buffer
- * @netfs_data: An arbitrary piece of data to be kept in the cookie to
- * represent the cache object to the netfs
- * @object_size: The initial size of object
- * @enable: Whether or not to enable a data cookie immediately
+ * fscache_unuse_cookie - Cease usage of cookie attached to an object
+ * @object: Object description
+ * @aux_data: Updated auxiliary data (or NULL)
+ * @object_size: Revised size of the object (or NULL)
  *
- * This function is used to inform FS-Cache about part of an index hierarchy
- * that can be used to locate files.  This is done by requesting a cookie for
- * each index in the path to the file.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
+ * Cease usage of the cookie attached to an object.  When the users count
+ * reaches zero then the cookie relinquishment will be permitted to proceed.
  */
-static inline
-struct fscache_cookie *fscache_acquire_cookie(
-	struct fscache_cookie *parent,
-	const struct fscache_cookie_def *def,
-	const void *index_key,
-	size_t index_key_len,
-	const void *aux_data,
-	size_t aux_data_len,
-	void *netfs_data,
-	loff_t object_size,
-	bool enable)
+static inline void fscache_unuse_cookie(struct fscache_cookie *cookie,
+					const void *aux_data,
+					const loff_t *object_size)
 {
-	if (fscache_cookie_valid(parent) && fscache_cookie_enabled(parent))
-		return __fscache_acquire_cookie(parent, def,
-						index_key, index_key_len,
-						aux_data, aux_data_len,
-						netfs_data, object_size, enable);
-	else
-		return NULL;
+	if (fscache_cookie_valid(cookie))
+		__fscache_unuse_cookie(cookie, aux_data, object_size);
 }
 
 /**
  * fscache_relinquish_cookie - Return the cookie to the cache, maybe discarding
  * it
  * @cookie: The cookie being returned
- * @aux_data: The updated auxiliary data for the cookie (may be NULL)
  * @retire: True if the cache object the cookie represents is to be discarded
  *
  * This function returns a cookie to the cache, forcibly discarding the
- * associated cache object if retire is set to true.  The opportunity is
- * provided to update the auxiliary data in the cache before the object is
- * disconnected.
+ * associated cache object if retire is set to true.
  *
  * See Documentation/filesystems/caching/netfs-api.rst for a complete
  * description.
  */
 static inline
-void fscache_relinquish_cookie(struct fscache_cookie *cookie,
-			       const void *aux_data,
-			       bool retire)
+void fscache_relinquish_cookie(struct fscache_cookie *cookie, bool retire)
 {
 	if (fscache_cookie_valid(cookie))
-		__fscache_relinquish_cookie(cookie, aux_data, retire);
+		__fscache_relinquish_cookie(cookie, retire);
 }
 
-/**
- * fscache_check_consistency - Request validation of a cache's auxiliary data
- * @cookie: The cookie representing the cache object
- * @aux_data: The updated auxiliary data for the cookie (may be NULL)
- *
- * Request an consistency check from fscache, which passes the request to the
- * backing cache.  The auxiliary data on the cookie will be updated first if
- * @aux_data is set.
- *
- * Returns 0 if consistent and -ESTALE if inconsistent.  May also
- * return -ENOMEM and -ERESTARTSYS.
+/*
+ * Find the auxiliary data on a cookie.
  */
-static inline
-int fscache_check_consistency(struct fscache_cookie *cookie,
-			      const void *aux_data)
+static inline void *fscache_get_aux(struct fscache_cookie *cookie)
 {
-	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
-		return __fscache_check_consistency(cookie, aux_data);
+	if (cookie->aux_len <= sizeof(cookie->inline_aux))
+		return cookie->inline_aux;
 	else
-		return 0;
+		return cookie->aux;
 }
 
-/**
- * fscache_update_cookie - Request that a cache object be updated
- * @cookie: The cookie representing the cache object
- * @aux_data: The updated auxiliary data for the cookie (may be NULL)
- *
- * Request an update of the index data for the cache object associated with the
- * cookie.  The auxiliary data on the cookie will be updated first if @aux_data
- * is set.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
+/*
+ * Update the auxiliary data on a cookie.
  */
 static inline
-void fscache_update_cookie(struct fscache_cookie *cookie, const void *aux_data)
+void fscache_update_aux(struct fscache_cookie *cookie,
+			const void *aux_data, const loff_t *object_size)
 {
-	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
-		__fscache_update_cookie(cookie, aux_data);
+	void *p = fscache_get_aux(cookie);
+
+	if (aux_data && p)
+		memcpy(p, aux_data, cookie->aux_len);
+	if (object_size)
+		cookie->object_size = *object_size;
 }
 
-/**
- * fscache_pin_cookie - Pin a data-storage cache object in its cache
- * @cookie: The cookie representing the cache object
- *
- * Permit data-storage cache objects to be pinned in the cache.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
+#ifdef CONFIG_FSCACHE_STATS
+extern atomic_t fscache_n_updates;
+#endif
+
 static inline
-int fscache_pin_cookie(struct fscache_cookie *cookie)
+void __fscache_update_cookie(struct fscache_cookie *cookie, const void *aux_data,
+			     const loff_t *object_size)
 {
-	return -ENOBUFS;
+#ifdef CONFIG_FSCACHE_STATS
+	atomic_inc(&fscache_n_updates);
+#endif
+	fscache_update_aux(cookie, aux_data, object_size);
+	smp_wmb();
+	set_bit(FSCACHE_COOKIE_NEEDS_UPDATE, &cookie->flags);
 }
 
 /**
- * fscache_pin_cookie - Unpin a data-storage cache object in its cache
+ * fscache_update_cookie - Request that a cache object be updated
  * @cookie: The cookie representing the cache object
+ * @aux_data: The updated auxiliary data for the cookie (may be NULL)
+ * @object_size: The current size of the object (may be NULL)
  *
- * Permit data-storage cache objects to be unpinned from the cache.
+ * Request an update of the index data for the cache object associated with the
+ * cookie.  The auxiliary data on the cookie will be updated first if @aux_data
+ * is set and the object size will be updated and the object possibly trimmed
+ * if @object_size is set.
  *
  * See Documentation/filesystems/caching/netfs-api.rst for a complete
  * description.
  */
 static inline
-void fscache_unpin_cookie(struct fscache_cookie *cookie)
+void fscache_update_cookie(struct fscache_cookie *cookie, const void *aux_data,
+			   const loff_t *object_size)
 {
+	if (fscache_cookie_enabled(cookie))
+		__fscache_update_cookie(cookie, aux_data, object_size);
 }
 
 /**
- * fscache_attr_changed - Notify cache that an object's attributes changed
+ * fscache_resize_cookie - Request that a cache object be resized
  * @cookie: The cookie representing the cache object
+ * @new_size: The new size of the object (may be NULL)
  *
- * Send a notification to the cache indicating that an object's attributes have
- * changed.  This includes the data size.  These attributes will be obtained
- * through the get_attr() cookie definition op.
+ * Request that the size of an object be changed.
  *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
+ * See Documentation/filesystems/caching/netfs-api.txt for a complete
  * description.
  */
 static inline
-int fscache_attr_changed(struct fscache_cookie *cookie)
+void fscache_resize_cookie(struct fscache_cookie *cookie, loff_t new_size)
 {
-	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
-		return __fscache_attr_changed(cookie);
-	else
-		return -ENOBUFS;
+	if (fscache_cookie_enabled(cookie))
+		__fscache_resize_cookie(cookie, new_size);
 }
 
 /**
  * fscache_invalidate - Notify cache that an object needs invalidation
  * @cookie: The cookie representing the cache object
+ * @aux_data: The updated auxiliary data for the cookie (may be NULL)
+ * @size: The revised size of the object.
+ * @flags: Invalidation flags (FSCACHE_INVAL_*)
  *
  * Notify the cache that an object is needs to be invalidated and that it
- * should abort any retrievals or stores it is doing on the cache.  The object
- * is then marked non-caching until such time as the invalidation is complete.
- *
- * This can be called with spinlocks held.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-void fscache_invalidate(struct fscache_cookie *cookie)
-{
-	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
-		__fscache_invalidate(cookie);
-}
-
-/**
- * fscache_wait_on_invalidate - Wait for invalidation to complete
- * @cookie: The cookie representing the cache object
+ * should abort any retrievals or stores it is doing on the cache.  This
+ * increments inval_counter on the cookie which can be used by the caller to
+ * reconsider I/O requests as they complete.
  *
- * Wait for the invalidation of an object to complete.
+ * If @flags has FSCACHE_INVAL_DIO_WRITE set, this indicates that this is due
+ * to a direct I/O write and will cause caching to be disabled on this cookie
+ * until it is completely unused.
  *
  * See Documentation/filesystems/caching/netfs-api.rst for a complete
  * description.
  */
 static inline
-void fscache_wait_on_invalidate(struct fscache_cookie *cookie)
+void fscache_invalidate(struct fscache_cookie *cookie,
+			const void *aux_data, loff_t size, unsigned int flags)
 {
-	if (fscache_cookie_valid(cookie))
-		__fscache_wait_on_invalidate(cookie);
+	if (fscache_cookie_enabled(cookie))
+		__fscache_invalidate(cookie, aux_data, size, flags);
 }
 
 /**
- * fscache_reserve_space - Reserve data space for a cached object
- * @cookie: The cookie representing the cache object
- * @i_size: The amount of space to be reserved
- *
- * Reserve an amount of space in the cache for the cache object attached to a
- * cookie so that a write to that object within the space can always be
- * honoured.
+ * fscache_operation_valid - Return true if operations resources are usable
+ * @cres: The resources to check.
  *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
+ * Returns a pointer to the operations table if usable or NULL if not.
  */
 static inline
-int fscache_reserve_space(struct fscache_cookie *cookie, loff_t size)
+const struct netfs_cache_ops *fscache_operation_valid(const struct netfs_cache_resources *cres)
 {
-	return -ENOBUFS;
+	return fscache_resources_valid(cres) ? cres->ops : NULL;
 }
 
-#ifdef FSCACHE_USE_NEW_IO_API
-
 /**
  * fscache_begin_read_operation - Begin a read operation for the netfs lib
- * @rreq: The read request being undertaken
+ * @cres: The cache resources for the read being performed
  * @cookie: The cookie representing the cache object
  *
- * Begin a read operation on behalf of the netfs helper library.  @rreq
- * indicates the read request to which the operation state should be attached;
- * @cookie indicates the cache object that will be accessed.
+ * Begin a read operation on behalf of the netfs helper library.  @cres
+ * indicates the cache resources to which the operation state should be
+ * attached; @cookie indicates the cache object that will be accessed.
  *
  * This is intended to be called from the ->begin_cache_operation() netfs lib
  * operation as implemented by the network filesystem.
  *
+ * @cres->inval_counter is set from @cookie->inval_counter for comparison at
+ * the end of the operation.  This allows invalidation during the operation to
+ * be detected by the caller.
+ *
  * Returns:
  * * 0		- Success
  * * -ENOBUFS	- No caching available
  * * Other error code from the cache, such as -ENOMEM.
  */
 static inline
-int fscache_begin_read_operation(struct netfs_read_request *rreq,
+int fscache_begin_read_operation(struct netfs_cache_resources *cres,
 				 struct fscache_cookie *cookie)
 {
-	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
-		return __fscache_begin_read_operation(rreq, cookie);
+	if (fscache_cookie_enabled(cookie))
+		return __fscache_begin_read_operation(cres, cookie);
 	return -ENOBUFS;
 }
 
-#else /* FSCACHE_USE_NEW_IO_API */
-
-/**
- * fscache_read_or_alloc_page - Read a page from the cache or allocate a block
- * in which to store it
- * @cookie: The cookie representing the cache object
- * @page: The netfs page to fill if possible
- * @end_io_func: The callback to invoke when and if the page is filled
- * @context: An arbitrary piece of data to pass on to end_io_func()
- * @gfp: The conditions under which memory allocation should be made
- *
- * Read a page from the cache, or if that's not possible make a potential
- * one-block reservation in the cache into which the page may be stored once
- * fetched from the server.
- *
- * If the page is not backed by the cache object, or if it there's some reason
- * it can't be, -ENOBUFS will be returned and nothing more will be done for
- * that page.
- *
- * Else, if that page is backed by the cache, a read will be initiated directly
- * to the netfs's page and 0 will be returned by this function.  The
- * end_io_func() callback will be invoked when the operation terminates on a
- * completion or failure.  Note that the callback may be invoked before the
- * return.
- *
- * Else, if the page is unbacked, -ENODATA is returned and a block may have
- * been allocated in the cache.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-int fscache_read_or_alloc_page(struct fscache_cookie *cookie,
-			       struct page *page,
-			       fscache_rw_complete_t end_io_func,
-			       void *context,
-			       gfp_t gfp)
-{
-	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
-		return __fscache_read_or_alloc_page(cookie, page, end_io_func,
-						    context, gfp);
-	else
-		return -ENOBUFS;
-}
-
 /**
- * fscache_read_or_alloc_pages - Read pages from the cache and/or allocate
- * blocks in which to store them
- * @cookie: The cookie representing the cache object
- * @mapping: The netfs inode mapping to which the pages will be attached
- * @pages: A list of potential netfs pages to be filled
- * @nr_pages: Number of pages to be read and/or allocated
- * @end_io_func: The callback to invoke when and if each page is filled
- * @context: An arbitrary piece of data to pass on to end_io_func()
- * @gfp: The conditions under which memory allocation should be made
- *
- * Read a set of pages from the cache, or if that's not possible, attempt to
- * make a potential one-block reservation for each page in the cache into which
- * that page may be stored once fetched from the server.
- *
- * If some pages are not backed by the cache object, or if it there's some
- * reason they can't be, -ENOBUFS will be returned and nothing more will be
- * done for that pages.
- *
- * Else, if some of the pages are backed by the cache, a read will be initiated
- * directly to the netfs's page and 0 will be returned by this function.  The
- * end_io_func() callback will be invoked when the operation terminates on a
- * completion or failure.  Note that the callback may be invoked before the
- * return.
- *
- * Else, if a page is unbacked, -ENODATA is returned and a block may have
- * been allocated in the cache.
- *
- * Because the function may want to return all of -ENOBUFS, -ENODATA and 0 in
- * regard to different pages, the return values are prioritised in that order.
- * Any pages submitted for reading are removed from the pages list.
+ * fscache_read - Start a read from the cache.
+ * @cres: The cache resources to use
+ * @start_pos: The beginning file offset in the cache file
+ * @iter: The buffer to fill - and also the length
+ * @read_hole: How to handle a hole in the data.
+ * @term_func: The function to call upon completion
+ * @term_func_priv: The private data for @term_func
  *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-int fscache_read_or_alloc_pages(struct fscache_cookie *cookie,
-				struct address_space *mapping,
-				struct list_head *pages,
-				unsigned *nr_pages,
-				fscache_rw_complete_t end_io_func,
-				void *context,
-				gfp_t gfp)
-{
-	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
-		return __fscache_read_or_alloc_pages(cookie, mapping, pages,
-						     nr_pages, end_io_func,
-						     context, gfp);
-	else
-		return -ENOBUFS;
-}
-
-/**
- * fscache_alloc_page - Allocate a block in which to store a page
- * @cookie: The cookie representing the cache object
- * @page: The netfs page to allocate a page for
- * @gfp: The conditions under which memory allocation should be made
+ * Start a read from the cache.  @cres indicates the cache object to read from
+ * and must be obtained by a call to fscache_begin_operation() beforehand.
  *
- * Request Allocation a block in the cache in which to store a netfs page
- * without retrieving any contents from the cache.
+ * The data is read into the iterator, @iter, and that also indicates the size
+ * of the operation.  @start_pos is the start position in the file, though if
+ * @seek_data is set appropriately, the cache can use SEEK_DATA to find the
+ * next piece of data, writing zeros for the hole into the iterator.
  *
- * If the page is not backed by a file then -ENOBUFS will be returned and
- * nothing more will be done, and no reservation will be made.
+ * Upon termination of the operation, @term_func will be called and supplied
+ * with @term_func_priv plus the amount of data written, if successful, or the
+ * error code otherwise.
  *
- * Else, a block will be allocated if one wasn't already, and 0 will be
- * returned
+ * @read_hole indicates how a partially populated region in the cache should be
+ * handled.  It can be one of a number of settings:
  *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-int fscache_alloc_page(struct fscache_cookie *cookie,
-		       struct page *page,
-		       gfp_t gfp)
-{
-	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
-		return __fscache_alloc_page(cookie, page, gfp);
-	else
-		return -ENOBUFS;
-}
-
-/**
- * fscache_readpages_cancel - Cancel read/alloc on pages
- * @cookie: The cookie representing the inode's cache object.
- * @pages: The netfs pages that we canceled write on in readpages()
+ *	NETFS_READ_HOLE_IGNORE - Just try to read (may return a short read).
  *
- * Uncache/unreserve the pages reserved earlier in readpages() via
- * fscache_readpages_or_alloc() and similar.  In most successful caches in
- * readpages() this doesn't do anything.  In cases when the underlying netfs's
- * readahead failed we need to clean up the pagelist (unmark and uncache).
+ *	NETFS_READ_HOLE_CLEAR - Seek for data, clearing the part of the buffer
+ *				skipped over, then do as for IGNORE.
  *
- * This function may sleep as it may have to clean up disk state.
+ *	NETFS_READ_HOLE_FAIL - Give ENODATA if we encounter a hole.
  */
 static inline
-void fscache_readpages_cancel(struct fscache_cookie *cookie,
-			      struct list_head *pages)
+int fscache_read(struct netfs_cache_resources *cres,
+		 loff_t start_pos,
+		 struct iov_iter *iter,
+		 enum netfs_read_from_hole read_hole,
+		 netfs_io_terminated_t term_func,
+		 void *term_func_priv)
 {
-	if (fscache_cookie_valid(cookie))
-		__fscache_readpages_cancel(cookie, pages);
+	const struct netfs_cache_ops *ops = fscache_operation_valid(cres);
+	return ops->read(cres, start_pos, iter, read_hole,
+			 term_func, term_func_priv);
 }
 
 /**
- * fscache_write_page - Request storage of a page in the cache
+ * fscache_begin_write_operation - Begin a write operation for the netfs lib
+ * @cres: The cache resources for the write being performed
  * @cookie: The cookie representing the cache object
- * @page: The netfs page to store
- * @object_size: Updated size of object
- * @gfp: The conditions under which memory allocation should be made
  *
- * Request the contents of the netfs page be written into the cache.  This
- * request may be ignored if no cache block is currently allocated, in which
- * case it will return -ENOBUFS.
+ * Begin a write operation on behalf of the netfs helper library.  @cres
+ * indicates the cache resources to which the operation state should be
+ * attached; @cookie indicates the cache object that will be accessed.
  *
- * If a cache block was already allocated, a write will be initiated and 0 will
- * be returned.  The PG_fscache_write page bit is set immediately and will then
- * be cleared at the completion of the write to indicate the success or failure
- * of the operation.  Note that the completion may happen before the return.
+ * @cres->inval_counter is set from @cookie->inval_counter for comparison at
+ * the end of the operation.  This allows invalidation during the operation to
+ * be detected by the caller.
  *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
+ * Returns:
+ * * 0		- Success
+ * * -ENOBUFS	- No caching available
+ * * Other error code from the cache, such as -ENOMEM.
  */
 static inline
-int fscache_write_page(struct fscache_cookie *cookie,
-		       struct page *page,
-		       loff_t object_size,
-		       gfp_t gfp)
+int fscache_begin_write_operation(struct netfs_cache_resources *cres,
+				  struct fscache_cookie *cookie)
 {
-	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
-		return __fscache_write_page(cookie, page, object_size, gfp);
-	else
-		return -ENOBUFS;
+	if (fscache_cookie_enabled(cookie))
+		return __fscache_begin_write_operation(cres, cookie);
+	return -ENOBUFS;
 }
 
 /**
- * fscache_uncache_page - Indicate that caching is no longer required on a page
- * @cookie: The cookie representing the cache object
- * @page: The netfs page that was being cached.
+ * fscache_write - Start a write to the cache.
+ * @cres: The cache resources to use
+ * @start_pos: The beginning file offset in the cache file
+ * @iter: The data to write - and also the length
+ * @term_func: The function to call upon completion
+ * @term_func_priv: The private data for @term_func
  *
- * Tell the cache that we no longer want a page to be cached and that it should
- * remove any knowledge of the netfs page it may have.
+ * Start a write to the cache.  @cres indicates the cache object to write to and
+ * must be obtained by a call to fscache_begin_operation() beforehand.
  *
- * Note that this cannot cancel any outstanding I/O operations between this
- * page and the cache.
+ * The data to be written is obtained from the iterator, @iter, and that also
+ * indicates the size of the operation.  @start_pos is the start position in
+ * the file.
  *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
+ * Upon termination of the operation, @term_func will be called and supplied
+ * with @term_func_priv plus the amount of data written, if successful, or the
+ * error code otherwise.
  */
 static inline
-void fscache_uncache_page(struct fscache_cookie *cookie,
-			  struct page *page)
+int fscache_write(struct netfs_cache_resources *cres,
+		  loff_t start_pos,
+		  struct iov_iter *iter,
+		  netfs_io_terminated_t term_func,
+		  void *term_func_priv)
 {
-	if (fscache_cookie_valid(cookie))
-		__fscache_uncache_page(cookie, page);
+	const struct netfs_cache_ops *ops = fscache_operation_valid(cres);
+	return ops->write(cres, start_pos, iter, term_func, term_func_priv);
 }
 
 /**
- * fscache_check_page_write - Ask if a page is being writing to the cache
+ * fscache_clear_page_bits - Clear the PG_fscache bits from a set of pages
  * @cookie: The cookie representing the cache object
- * @page: The netfs page that is being cached.
- *
- * Ask the cache if a page is being written to the cache.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-bool fscache_check_page_write(struct fscache_cookie *cookie,
-			      struct page *page)
+ * @mapping: The netfs inode to use as the source
+ * @start: The start position in @mapping
+ * @len: The amount of data to unlock
+ * @caching: If PG_fscache has been set
+ *
+ * Clear the PG_fscache flag from a sequence of pages and wake up anyone who's
+ * waiting.
+ */
+static inline void fscache_clear_page_bits(struct fscache_cookie *cookie,
+					   struct address_space *mapping,
+					   loff_t start, size_t len,
+					   bool caching)
 {
-	if (fscache_cookie_valid(cookie))
-		return __fscache_check_page_write(cookie, page);
-	return false;
+	if (caching)
+		__fscache_clear_page_bits(mapping, start, len);
 }
 
 /**
- * fscache_wait_on_page_write - Wait for a page to complete writing to the cache
+ * fscache_write_to_cache - Save a write to the cache and clear PG_fscache
  * @cookie: The cookie representing the cache object
- * @page: The netfs page that is being cached.
- *
- * Ask the cache to wake us up when a page is no longer being written to the
- * cache.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-void fscache_wait_on_page_write(struct fscache_cookie *cookie,
-				struct page *page)
+ * @mapping: The netfs inode to use as the source
+ * @start: The start position in @mapping
+ * @len: The amount of data to write back
+ * @i_size: The new size of the inode
+ * @term_func: The function to call upon completion
+ * @term_func_priv: The private data for @term_func
+ * @caching: If PG_fscache has been set
+ *
+ * Helper function for a netfs to write dirty data from an inode into the cache
+ * object that's backing it.
+ *
+ * @start and @len describe the range of the data.  This does not need to be
+ * page-aligned, but to satisfy DIO requirements, the cache may expand it up to
+ * the page boundaries on either end.  All the pages covering the range must be
+ * marked with PG_fscache.
+ *
+ * If given, @term_func will be called upon completion and supplied with
+ * @term_func_priv.  Note that the PG_fscache flags will have been cleared by
+ * this point, so the netfs must retain its own pin on the mapping.
+ */
+static inline 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 caching)
 {
-	if (fscache_cookie_valid(cookie))
-		__fscache_wait_on_page_write(cookie, page);
-}
+	if (caching)
+		__fscache_write_to_cache(cookie, mapping, start, len, i_size,
+					 term_func, term_func_priv, caching);
+	else if (term_func)
+		term_func(term_func_priv, -ENOBUFS, false);
 
-/**
- * fscache_maybe_release_page - Consider releasing a page, cancelling a store
- * @cookie: The cookie representing the cache object
- * @page: The netfs page that is being cached.
- * @gfp: The gfp flags passed to releasepage()
- *
- * Consider releasing a page for the vmscan algorithm, on behalf of the netfs's
- * releasepage() call.  A storage request on the page may cancelled if it is
- * not currently being processed.
- *
- * The function returns true if the page no longer has a storage request on it,
- * and false if a storage request is left in place.  If true is returned, the
- * page will have been passed to fscache_uncache_page().  If false is returned
- * the page cannot be freed yet.
- */
-static inline
-bool fscache_maybe_release_page(struct fscache_cookie *cookie,
-				struct page *page,
-				gfp_t gfp)
-{
-	if (fscache_cookie_valid(cookie) && PageFsCache(page))
-		return __fscache_maybe_release_page(cookie, page, gfp);
-	return true;
 }
 
+#if __fscache_available
+extern int fscache_set_page_dirty(struct page *page, struct fscache_cookie *cookie);
+#else
+#define fscache_set_page_dirty(PAGE, COOKIE) (__set_page_dirty_nobuffers((PAGE)))
+#endif
+
 /**
- * fscache_uncache_all_inode_pages - Uncache all an inode's pages
- * @cookie: The cookie representing the inode's cache object.
- * @inode: The inode to uncache pages from.
- *
- * Uncache all the pages in an inode that are marked PG_fscache, assuming them
- * to be associated with the given cookie.
+ * fscache_unpin_writeback - Unpin writeback resources
+ * @wbc: The writeback control
+ * @cookie: The cookie referring to the cache object
  *
- * This function may sleep.  It will wait for pages that are being written out
- * and will wait whilst the PG_fscache mark is removed by the cache.
+ * Unpin the writeback resources pinned by fscache_set_page_dirty().  This is
+ * intended to be called by the netfs's ->write_inode() method.
  */
-static inline
-void fscache_uncache_all_inode_pages(struct fscache_cookie *cookie,
-				     struct inode *inode)
+static inline void fscache_unpin_writeback(struct writeback_control *wbc,
+					   struct fscache_cookie *cookie)
 {
-	if (fscache_cookie_valid(cookie))
-		__fscache_uncache_all_inode_pages(cookie, inode);
+	if (wbc->unpinned_fscache_wb)
+		fscache_unuse_cookie(cookie, NULL, NULL);
 }
 
-#endif /* FSCACHE_USE_NEW_IO_API */
-
 /**
- * fscache_disable_cookie - Disable a cookie
- * @cookie: The cookie representing the cache object
- * @aux_data: The updated auxiliary data for the cookie (may be NULL)
- * @invalidate: Invalidate the backing object
- *
- * Disable a cookie from accepting further alloc, read, write, invalidate,
- * update or acquire operations.  Outstanding operations can still be waited
- * upon and pages can still be uncached and the cookie relinquished.
- *
- * This will not return until all outstanding operations have completed.
+ * fscache_clear_inode_writeback - Clear writeback resources pinned by an inode
+ * @cookie: The cookie referring to the cache object
+ * @inode: The inode to clean up
+ * @aux: Auxiliary data to apply to the inode
  *
- * If @invalidate is set, then the backing object will be invalidated and
- * detached, otherwise it will just be detached.
- *
- * If @aux_data is set, then auxiliary data will be updated from that.
+ * Clear any writeback resources held by an inode when the inode is evicted.
+ * This must be called before clear_inode() is called.
  */
-static inline
-void fscache_disable_cookie(struct fscache_cookie *cookie,
-			    const void *aux_data,
-			    bool invalidate)
+static inline void fscache_clear_inode_writeback(struct fscache_cookie *cookie,
+						 struct inode *inode,
+						 const void *aux)
 {
-	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
-		__fscache_disable_cookie(cookie, aux_data, invalidate);
+	if (inode->i_state & I_PINNING_FSCACHE_WB) {
+		loff_t i_size = i_size_read(inode);
+		fscache_unuse_cookie(cookie, aux, &i_size);
+	}
 }
 
 /**
- * fscache_enable_cookie - Reenable a cookie
- * @cookie: The cookie representing the cache object
- * @aux_data: The updated auxiliary data for the cookie (may be NULL)
- * @object_size: Current size of object
- * @can_enable: A function to permit enablement once lock is held
- * @data: Data for can_enable()
- *
- * Reenable a previously disabled cookie, allowing it to accept further alloc,
- * read, write, invalidate, update or acquire operations.  An attempt will be
- * made to immediately reattach the cookie to a backing object.  If @aux_data
- * is set, the auxiliary data attached to the cookie will be updated.
+ * fscache_note_page_release - Note that a netfs page got released
+ * @cookie: The cookie corresponding to the file
  *
- * The can_enable() function is called (if not NULL) once the enablement lock
- * is held to rule on whether enablement is still permitted to go ahead.
+ * Note that a page that has been copied to the cache has been released.  This
+ * means that future reads will need to look in the cache to see if it's there.
  */
 static inline
-void fscache_enable_cookie(struct fscache_cookie *cookie,
-			   const void *aux_data,
-			   loff_t object_size,
-			   bool (*can_enable)(void *data),
-			   void *data)
+void fscache_note_page_release(struct fscache_cookie *cookie)
 {
-	if (fscache_cookie_valid(cookie) && !fscache_cookie_enabled(cookie))
-		__fscache_enable_cookie(cookie, aux_data, object_size,
-					can_enable, data);
+	if (cookie &&
+	    test_bit(FSCACHE_COOKIE_HAVE_DATA, &cookie->flags) &&
+	    test_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags))
+		clear_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags);
 }
 
 #endif /* _LINUX_FSCACHE_H */
diff --git a/include/linux/netfs.h b/include/linux/netfs.h
index ca0683b9e3d1..b46c39d98bbd 100644
--- a/include/linux/netfs.h
+++ b/include/linux/netfs.h
@@ -124,6 +124,7 @@ struct netfs_cache_resources {
 	void				*cache_priv;
 	void				*cache_priv2;
 	unsigned int			debug_id;	/* Cookie debug ID */
+	unsigned int			inval_counter;	/* object->inval_counter at begin_op */
 };
 
 /*
@@ -196,6 +197,15 @@ struct netfs_read_request_ops {
 };
 
 /*
+ * How to handle reading from a hole.
+ */
+enum netfs_read_from_hole {
+	NETFS_READ_HOLE_IGNORE,
+	NETFS_READ_HOLE_CLEAR,
+	NETFS_READ_HOLE_FAIL,
+};
+
+/*
  * Table of operations for access to a cache.  This is obtained by
  * rreq->ops->begin_cache_operation().
  */
@@ -207,7 +217,7 @@ struct netfs_cache_ops {
 	int (*read)(struct netfs_cache_resources *cres,
 		    loff_t start_pos,
 		    struct iov_iter *iter,
-		    bool seek_data,
+		    enum netfs_read_from_hole read_hole,
 		    netfs_io_terminated_t term_func,
 		    void *term_func_priv);
 
@@ -232,7 +242,8 @@ struct netfs_cache_ops {
 	 * actually do.
 	 */
 	int (*prepare_write)(struct netfs_cache_resources *cres,
-			     loff_t *_start, size_t *_len, loff_t i_size);
+			     loff_t *_start, size_t *_len, loff_t i_size,
+			     bool no_space_allocated_yet);
 };
 
 struct readahead_control;
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 05f249f20f55..00835bacd236 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -275,7 +275,6 @@ struct nfs4_copy_state {
 #define NFS_INO_ACL_LRU_SET	(2)		/* Inode is on the LRU list */
 #define NFS_INO_INVALIDATING	(3)		/* inode is being invalidated */
 #define NFS_INO_FSCACHE		(5)		/* inode can be cached by FS-Cache */
-#define NFS_INO_FSCACHE_LOCK	(6)		/* FS-Cache cookie management lock */
 #define NFS_INO_FORCE_READDIR	(7)		/* force readdirplus */
 #define NFS_INO_LAYOUTCOMMIT	(9)		/* layoutcommit required */
 #define NFS_INO_LAYOUTCOMMITTING (10)		/* layoutcommit inflight */
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index 2a9acbfe00f0..77b2dba27bbb 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -120,11 +120,6 @@ struct nfs_client {
 	 * This is used to generate the mv0 callback address.
 	 */
 	char			cl_ipaddr[48];
-
-#ifdef CONFIG_NFS_FSCACHE
-	struct fscache_cookie	*fscache;	/* client index cache cookie */
-#endif
-
 	struct net		*cl_net;
 	struct list_head	pending_cb_stateids;
 };
@@ -194,8 +189,8 @@ struct nfs_server {
 	struct nfs_auth_info	auth_info;	/* parsed auth flavors */
 
 #ifdef CONFIG_NFS_FSCACHE
-	struct nfs_fscache_key	*fscache_key;	/* unique key for superblock */
-	struct fscache_cookie	*fscache;	/* superblock cookie */
+	struct fscache_volume	*fscache;	/* superblock cookie */
+	char			*fscache_uniq;	/* Uniquifier (or NULL) */
 #endif
 
 	u32			pnfs_blksize;	/* layout_blksize attr */
diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index 3bfd487d1dd2..fec248ab1fec 100644
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -68,6 +68,7 @@ struct writeback_control {
 	unsigned for_reclaim:1;		/* Invoked from the page allocator */
 	unsigned range_cyclic:1;	/* range_start is cyclic */
 	unsigned for_sync:1;		/* sync(2) WB_SYNC_ALL writeback */
+	unsigned unpinned_fscache_wb:1;	/* Cleared I_PINNING_FSCACHE_WB */
 
 	/*
 	 * When writeback IOs are bounced through async layers, only the
diff --git a/include/trace/events/cachefiles.h b/include/trace/events/cachefiles.h
index 920b6a303d60..1172529b5b49 100644
--- a/include/trace/events/cachefiles.h
+++ b/include/trace/events/cachefiles.h
@@ -1,7 +1,7 @@
 /* SPDX-License-Identifier: GPL-2.0-or-later */
 /* CacheFiles tracepoints
  *
- * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved.
+ * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
  * Written by David Howells (dhowells@redhat.com)
  */
 #undef TRACE_SYSTEM
@@ -19,9 +19,83 @@
 #define __CACHEFILES_DECLARE_TRACE_ENUMS_ONCE_ONLY
 
 enum cachefiles_obj_ref_trace {
-	cachefiles_obj_put_wait_retry = fscache_obj_ref__nr_traces,
-	cachefiles_obj_put_wait_timeo,
-	cachefiles_obj_ref__nr_traces
+	cachefiles_obj_get_ioreq,
+	cachefiles_obj_new,
+	cachefiles_obj_put_alloc_fail,
+	cachefiles_obj_put_detach,
+	cachefiles_obj_put_ioreq,
+	cachefiles_obj_see_clean_commit,
+	cachefiles_obj_see_clean_delete,
+	cachefiles_obj_see_clean_drop_tmp,
+	cachefiles_obj_see_lookup_cookie,
+	cachefiles_obj_see_lookup_failed,
+	cachefiles_obj_see_withdraw_cookie,
+	cachefiles_obj_see_withdrawal,
+};
+
+enum fscache_why_object_killed {
+	FSCACHE_OBJECT_IS_STALE,
+	FSCACHE_OBJECT_IS_WEIRD,
+	FSCACHE_OBJECT_INVALIDATED,
+	FSCACHE_OBJECT_NO_SPACE,
+	FSCACHE_OBJECT_WAS_RETIRED,
+	FSCACHE_OBJECT_WAS_CULLED,
+	FSCACHE_VOLUME_IS_WEIRD,
+};
+
+enum cachefiles_coherency_trace {
+	cachefiles_coherency_check_aux,
+	cachefiles_coherency_check_content,
+	cachefiles_coherency_check_dirty,
+	cachefiles_coherency_check_len,
+	cachefiles_coherency_check_objsize,
+	cachefiles_coherency_check_ok,
+	cachefiles_coherency_check_type,
+	cachefiles_coherency_check_xattr,
+	cachefiles_coherency_set_fail,
+	cachefiles_coherency_set_ok,
+	cachefiles_coherency_vol_check_cmp,
+	cachefiles_coherency_vol_check_ok,
+	cachefiles_coherency_vol_check_xattr,
+	cachefiles_coherency_vol_set_fail,
+	cachefiles_coherency_vol_set_ok,
+};
+
+enum cachefiles_trunc_trace {
+	cachefiles_trunc_dio_adjust,
+	cachefiles_trunc_expand_tmpfile,
+	cachefiles_trunc_shrink,
+};
+
+enum cachefiles_prepare_read_trace {
+	cachefiles_trace_read_after_eof,
+	cachefiles_trace_read_found_hole,
+	cachefiles_trace_read_found_part,
+	cachefiles_trace_read_have_data,
+	cachefiles_trace_read_no_data,
+	cachefiles_trace_read_no_file,
+	cachefiles_trace_read_seek_error,
+	cachefiles_trace_read_seek_nxio,
+};
+
+enum cachefiles_error_trace {
+	cachefiles_trace_fallocate_error,
+	cachefiles_trace_getxattr_error,
+	cachefiles_trace_link_error,
+	cachefiles_trace_lookup_error,
+	cachefiles_trace_mkdir_error,
+	cachefiles_trace_notify_change_error,
+	cachefiles_trace_open_error,
+	cachefiles_trace_read_error,
+	cachefiles_trace_remxattr_error,
+	cachefiles_trace_rename_error,
+	cachefiles_trace_seek_error,
+	cachefiles_trace_setxattr_error,
+	cachefiles_trace_statfs_error,
+	cachefiles_trace_tmpfile_error,
+	cachefiles_trace_trunc_error,
+	cachefiles_trace_unlink_error,
+	cachefiles_trace_write_error,
 };
 
 #endif
@@ -31,21 +105,78 @@ enum cachefiles_obj_ref_trace {
  */
 #define cachefiles_obj_kill_traces				\
 	EM(FSCACHE_OBJECT_IS_STALE,	"stale")		\
+	EM(FSCACHE_OBJECT_IS_WEIRD,	"weird")		\
+	EM(FSCACHE_OBJECT_INVALIDATED,	"inval")		\
 	EM(FSCACHE_OBJECT_NO_SPACE,	"no_space")		\
 	EM(FSCACHE_OBJECT_WAS_RETIRED,	"was_retired")		\
-	E_(FSCACHE_OBJECT_WAS_CULLED,	"was_culled")
+	EM(FSCACHE_OBJECT_WAS_CULLED,	"was_culled")		\
+	E_(FSCACHE_VOLUME_IS_WEIRD,	"volume_weird")
 
 #define cachefiles_obj_ref_traces					\
-	EM(fscache_obj_get_add_to_deps,		"GET add_to_deps")	\
-	EM(fscache_obj_get_queue,		"GET queue")		\
-	EM(fscache_obj_put_alloc_fail,		"PUT alloc_fail")	\
-	EM(fscache_obj_put_attach_fail,		"PUT attach_fail")	\
-	EM(fscache_obj_put_drop_obj,		"PUT drop_obj")		\
-	EM(fscache_obj_put_enq_dep,		"PUT enq_dep")		\
-	EM(fscache_obj_put_queue,		"PUT queue")		\
-	EM(fscache_obj_put_work,		"PUT work")		\
-	EM(cachefiles_obj_put_wait_retry,	"PUT wait_retry")	\
-	E_(cachefiles_obj_put_wait_timeo,	"PUT wait_timeo")
+	EM(cachefiles_obj_get_ioreq,		"GET ioreq")		\
+	EM(cachefiles_obj_new,			"NEW obj")		\
+	EM(cachefiles_obj_put_alloc_fail,	"PUT alloc_fail")	\
+	EM(cachefiles_obj_put_detach,		"PUT detach")		\
+	EM(cachefiles_obj_put_ioreq,		"PUT ioreq")		\
+	EM(cachefiles_obj_see_clean_commit,	"SEE clean_commit")	\
+	EM(cachefiles_obj_see_clean_delete,	"SEE clean_delete")	\
+	EM(cachefiles_obj_see_clean_drop_tmp,	"SEE clean_drop_tmp")	\
+	EM(cachefiles_obj_see_lookup_cookie,	"SEE lookup_cookie")	\
+	EM(cachefiles_obj_see_lookup_failed,	"SEE lookup_failed")	\
+	EM(cachefiles_obj_see_withdraw_cookie,	"SEE withdraw_cookie")	\
+	E_(cachefiles_obj_see_withdrawal,	"SEE withdrawal")
+
+#define cachefiles_coherency_traces					\
+	EM(cachefiles_coherency_check_aux,	"BAD aux ")		\
+	EM(cachefiles_coherency_check_content,	"BAD cont")		\
+	EM(cachefiles_coherency_check_dirty,	"BAD dirt")		\
+	EM(cachefiles_coherency_check_len,	"BAD len ")		\
+	EM(cachefiles_coherency_check_objsize,	"BAD osiz")		\
+	EM(cachefiles_coherency_check_ok,	"OK      ")		\
+	EM(cachefiles_coherency_check_type,	"BAD type")		\
+	EM(cachefiles_coherency_check_xattr,	"BAD xatt")		\
+	EM(cachefiles_coherency_set_fail,	"SET fail")		\
+	EM(cachefiles_coherency_set_ok,		"SET ok  ")		\
+	EM(cachefiles_coherency_vol_check_cmp,	"VOL BAD cmp ")		\
+	EM(cachefiles_coherency_vol_check_ok,	"VOL OK      ")		\
+	EM(cachefiles_coherency_vol_check_xattr,"VOL BAD xatt")		\
+	EM(cachefiles_coherency_vol_set_fail,	"VOL SET fail")		\
+	E_(cachefiles_coherency_vol_set_ok,	"VOL SET ok  ")
+
+#define cachefiles_trunc_traces						\
+	EM(cachefiles_trunc_dio_adjust,		"DIOADJ")		\
+	EM(cachefiles_trunc_expand_tmpfile,	"EXPTMP")		\
+	E_(cachefiles_trunc_shrink,		"SHRINK")
+
+#define cachefiles_prepare_read_traces					\
+	EM(cachefiles_trace_read_after_eof,	"after-eof ")		\
+	EM(cachefiles_trace_read_found_hole,	"found-hole")		\
+	EM(cachefiles_trace_read_found_part,	"found-part")		\
+	EM(cachefiles_trace_read_have_data,	"have-data ")		\
+	EM(cachefiles_trace_read_no_data,	"no-data   ")		\
+	EM(cachefiles_trace_read_no_file,	"no-file   ")		\
+	EM(cachefiles_trace_read_seek_error,	"seek-error")		\
+	E_(cachefiles_trace_read_seek_nxio,	"seek-enxio")
+
+#define cachefiles_error_traces						\
+	EM(cachefiles_trace_fallocate_error,	"fallocate")		\
+	EM(cachefiles_trace_getxattr_error,	"getxattr")		\
+	EM(cachefiles_trace_link_error,		"link")			\
+	EM(cachefiles_trace_lookup_error,	"lookup")		\
+	EM(cachefiles_trace_mkdir_error,	"mkdir")		\
+	EM(cachefiles_trace_notify_change_error, "notify_change")	\
+	EM(cachefiles_trace_open_error,		"open")			\
+	EM(cachefiles_trace_read_error,		"read")			\
+	EM(cachefiles_trace_remxattr_error,	"remxattr")		\
+	EM(cachefiles_trace_rename_error,	"rename")		\
+	EM(cachefiles_trace_seek_error,		"seek")			\
+	EM(cachefiles_trace_setxattr_error,	"setxattr")		\
+	EM(cachefiles_trace_statfs_error,	"statfs")		\
+	EM(cachefiles_trace_tmpfile_error,	"tmpfile")		\
+	EM(cachefiles_trace_trunc_error,	"trunc")		\
+	EM(cachefiles_trace_unlink_error,	"unlink")		\
+	E_(cachefiles_trace_write_error,	"write")
+
 
 /*
  * Export enum symbols via userspace.
@@ -57,6 +188,10 @@ enum cachefiles_obj_ref_trace {
 
 cachefiles_obj_kill_traces;
 cachefiles_obj_ref_traces;
+cachefiles_coherency_traces;
+cachefiles_trunc_traces;
+cachefiles_prepare_read_traces;
+cachefiles_error_traces;
 
 /*
  * Now redefine the EM() and E_() macros to map the enums to the strings that
@@ -69,12 +204,12 @@ cachefiles_obj_ref_traces;
 
 
 TRACE_EVENT(cachefiles_ref,
-	    TP_PROTO(struct cachefiles_object *obj,
-		     struct fscache_cookie *cookie,
-		     enum cachefiles_obj_ref_trace why,
-		     int usage),
+	    TP_PROTO(unsigned int object_debug_id,
+		     unsigned int cookie_debug_id,
+		     int usage,
+		     enum cachefiles_obj_ref_trace why),
 
-	    TP_ARGS(obj, cookie, why, usage),
+	    TP_ARGS(object_debug_id, cookie_debug_id, usage, why),
 
 	    /* Note that obj may be NULL */
 	    TP_STRUCT__entry(
@@ -85,8 +220,8 @@ TRACE_EVENT(cachefiles_ref,
 			     ),
 
 	    TP_fast_assign(
-		    __entry->obj	= obj->fscache.debug_id;
-		    __entry->cookie	= cookie->debug_id;
+		    __entry->obj	= object_debug_id;
+		    __entry->cookie	= cookie_debug_id;
 		    __entry->usage	= usage;
 		    __entry->why	= why;
 			   ),
@@ -98,69 +233,65 @@ TRACE_EVENT(cachefiles_ref,
 
 TRACE_EVENT(cachefiles_lookup,
 	    TP_PROTO(struct cachefiles_object *obj,
-		     struct dentry *de,
-		     struct inode *inode),
+		     struct dentry *de),
 
-	    TP_ARGS(obj, de, inode),
+	    TP_ARGS(obj, de),
 
 	    TP_STRUCT__entry(
 		    __field(unsigned int,		obj	)
-		    __field(struct dentry *,		de	)
-		    __field(struct inode *,		inode	)
+		    __field(short,			error	)
+		    __field(unsigned long,		ino	)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->obj	= obj->fscache.debug_id;
-		    __entry->de		= de;
-		    __entry->inode	= inode;
+		    __entry->obj	= obj->debug_id;
+		    __entry->ino	= (!IS_ERR(de) && d_backing_inode(de) ?
+					   d_backing_inode(de)->i_ino : 0);
+		    __entry->error	= IS_ERR(de) ? PTR_ERR(de) : 0;
 			   ),
 
-	    TP_printk("o=%08x d=%p i=%p",
-		      __entry->obj, __entry->de, __entry->inode)
+	    TP_printk("o=%08x i=%lx e=%d",
+		      __entry->obj, __entry->ino, __entry->error)
 	    );
 
-TRACE_EVENT(cachefiles_mkdir,
-	    TP_PROTO(struct cachefiles_object *obj,
-		     struct dentry *de, int ret),
+TRACE_EVENT(cachefiles_tmpfile,
+	    TP_PROTO(struct cachefiles_object *obj, struct inode *backer),
 
-	    TP_ARGS(obj, de, ret),
+	    TP_ARGS(obj, backer),
 
 	    TP_STRUCT__entry(
-		    __field(unsigned int,		obj	)
-		    __field(struct dentry *,		de	)
-		    __field(int,			ret	)
+		    __field(unsigned int,			obj	)
+		    __field(unsigned int,			backer	)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->obj	= obj->fscache.debug_id;
-		    __entry->de		= de;
-		    __entry->ret	= ret;
+		    __entry->obj	= obj->debug_id;
+		    __entry->backer	= backer->i_ino;
 			   ),
 
-	    TP_printk("o=%08x d=%p r=%u",
-		      __entry->obj, __entry->de, __entry->ret)
+	    TP_printk("o=%08x b=%08x",
+		      __entry->obj,
+		      __entry->backer)
 	    );
 
-TRACE_EVENT(cachefiles_create,
-	    TP_PROTO(struct cachefiles_object *obj,
-		     struct dentry *de, int ret),
+TRACE_EVENT(cachefiles_link,
+	    TP_PROTO(struct cachefiles_object *obj, struct inode *backer),
 
-	    TP_ARGS(obj, de, ret),
+	    TP_ARGS(obj, backer),
 
 	    TP_STRUCT__entry(
-		    __field(unsigned int,		obj	)
-		    __field(struct dentry *,		de	)
-		    __field(int,			ret	)
+		    __field(unsigned int,			obj	)
+		    __field(unsigned int,			backer	)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->obj	= obj->fscache.debug_id;
-		    __entry->de		= de;
-		    __entry->ret	= ret;
+		    __entry->obj	= obj->debug_id;
+		    __entry->backer	= backer->i_ino;
 			   ),
 
-	    TP_printk("o=%08x d=%p r=%u",
-		      __entry->obj, __entry->de, __entry->ret)
+	    TP_printk("o=%08x b=%08x",
+		      __entry->obj,
+		      __entry->backer)
 	    );
 
 TRACE_EVENT(cachefiles_unlink,
@@ -178,7 +309,7 @@ TRACE_EVENT(cachefiles_unlink,
 			     ),
 
 	    TP_fast_assign(
-		    __entry->obj	= obj ? obj->fscache.debug_id : UINT_MAX;
+		    __entry->obj	= obj ? obj->debug_id : UINT_MAX;
 		    __entry->de		= de;
 		    __entry->why	= why;
 			   ),
@@ -205,7 +336,7 @@ TRACE_EVENT(cachefiles_rename,
 			     ),
 
 	    TP_fast_assign(
-		    __entry->obj	= obj ? obj->fscache.debug_id : UINT_MAX;
+		    __entry->obj	= obj ? obj->debug_id : UINT_MAX;
 		    __entry->de		= de;
 		    __entry->to		= to;
 		    __entry->why	= why;
@@ -216,103 +347,285 @@ TRACE_EVENT(cachefiles_rename,
 		      __print_symbolic(__entry->why, cachefiles_obj_kill_traces))
 	    );
 
-TRACE_EVENT(cachefiles_mark_active,
+TRACE_EVENT(cachefiles_coherency,
 	    TP_PROTO(struct cachefiles_object *obj,
-		     struct dentry *de),
+		     ino_t ino,
+		     enum cachefiles_content content,
+		     enum cachefiles_coherency_trace why),
 
-	    TP_ARGS(obj, de),
+	    TP_ARGS(obj, ino, content, why),
 
 	    /* Note that obj may be NULL */
 	    TP_STRUCT__entry(
-		    __field(unsigned int,		obj		)
-		    __field(struct dentry *,		de		)
+		    __field(unsigned int,			obj	)
+		    __field(enum cachefiles_coherency_trace,	why	)
+		    __field(enum cachefiles_content,		content	)
+		    __field(u64,				ino	)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->obj	= obj->fscache.debug_id;
-		    __entry->de		= de;
+		    __entry->obj	= obj->debug_id;
+		    __entry->why	= why;
+		    __entry->content	= content;
+		    __entry->ino	= ino;
 			   ),
 
-	    TP_printk("o=%08x d=%p",
-		      __entry->obj, __entry->de)
+	    TP_printk("o=%08x %s i=%llx c=%u",
+		      __entry->obj,
+		      __print_symbolic(__entry->why, cachefiles_coherency_traces),
+		      __entry->ino,
+		      __entry->content)
 	    );
 
-TRACE_EVENT(cachefiles_wait_active,
-	    TP_PROTO(struct cachefiles_object *obj,
-		     struct dentry *de,
-		     struct cachefiles_object *xobj),
+TRACE_EVENT(cachefiles_vol_coherency,
+	    TP_PROTO(struct cachefiles_volume *volume,
+		     ino_t ino,
+		     enum cachefiles_coherency_trace why),
 
-	    TP_ARGS(obj, de, xobj),
+	    TP_ARGS(volume, ino, why),
 
 	    /* Note that obj may be NULL */
 	    TP_STRUCT__entry(
-		    __field(unsigned int,		obj		)
-		    __field(unsigned int,		xobj		)
-		    __field(struct dentry *,		de		)
-		    __field(u16,			flags		)
-		    __field(u16,			fsc_flags	)
+		    __field(unsigned int,			vol	)
+		    __field(enum cachefiles_coherency_trace,	why	)
+		    __field(u64,				ino	)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->obj	= obj->fscache.debug_id;
-		    __entry->de		= de;
-		    __entry->xobj	= xobj->fscache.debug_id;
-		    __entry->flags	= xobj->flags;
-		    __entry->fsc_flags	= xobj->fscache.flags;
+		    __entry->vol	= volume->vcookie->debug_id;
+		    __entry->why	= why;
+		    __entry->ino	= ino;
 			   ),
 
-	    TP_printk("o=%08x d=%p wo=%08x wf=%x wff=%x",
-		      __entry->obj, __entry->de, __entry->xobj,
-		      __entry->flags, __entry->fsc_flags)
+	    TP_printk("V=%08x %s i=%llx",
+		      __entry->vol,
+		      __print_symbolic(__entry->why, cachefiles_coherency_traces),
+		      __entry->ino)
 	    );
 
-TRACE_EVENT(cachefiles_mark_inactive,
+TRACE_EVENT(cachefiles_prep_read,
+	    TP_PROTO(struct netfs_read_subrequest *sreq,
+		     enum netfs_read_source source,
+		     enum cachefiles_prepare_read_trace why,
+		     ino_t cache_inode),
+
+	    TP_ARGS(sreq, source, why, cache_inode),
+
+	    TP_STRUCT__entry(
+		    __field(unsigned int,		rreq		)
+		    __field(unsigned short,		index		)
+		    __field(unsigned short,		flags		)
+		    __field(enum netfs_read_source,	source		)
+		    __field(enum cachefiles_prepare_read_trace,	why	)
+		    __field(size_t,			len		)
+		    __field(loff_t,			start		)
+		    __field(unsigned int,		netfs_inode	)
+		    __field(unsigned int,		cache_inode	)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->rreq	= sreq->rreq->debug_id;
+		    __entry->index	= sreq->debug_index;
+		    __entry->flags	= sreq->flags;
+		    __entry->source	= source;
+		    __entry->why	= why;
+		    __entry->len	= sreq->len;
+		    __entry->start	= sreq->start;
+		    __entry->netfs_inode = sreq->rreq->inode->i_ino;
+		    __entry->cache_inode = cache_inode;
+			   ),
+
+	    TP_printk("R=%08x[%u] %s %s f=%02x s=%llx %zx ni=%x b=%x",
+		      __entry->rreq, __entry->index,
+		      __print_symbolic(__entry->source, netfs_sreq_sources),
+		      __print_symbolic(__entry->why, cachefiles_prepare_read_traces),
+		      __entry->flags,
+		      __entry->start, __entry->len,
+		      __entry->netfs_inode, __entry->cache_inode)
+	    );
+
+TRACE_EVENT(cachefiles_read,
+	    TP_PROTO(struct cachefiles_object *obj,
+		     struct inode *backer,
+		     loff_t start,
+		     size_t len),
+
+	    TP_ARGS(obj, backer, start, len),
+
+	    TP_STRUCT__entry(
+		    __field(unsigned int,			obj	)
+		    __field(unsigned int,			backer	)
+		    __field(size_t,				len	)
+		    __field(loff_t,				start	)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->obj	= obj->debug_id;
+		    __entry->backer	= backer->i_ino;
+		    __entry->start	= start;
+		    __entry->len	= len;
+			   ),
+
+	    TP_printk("o=%08x b=%08x s=%llx l=%zx",
+		      __entry->obj,
+		      __entry->backer,
+		      __entry->start,
+		      __entry->len)
+	    );
+
+TRACE_EVENT(cachefiles_write,
+	    TP_PROTO(struct cachefiles_object *obj,
+		     struct inode *backer,
+		     loff_t start,
+		     size_t len),
+
+	    TP_ARGS(obj, backer, start, len),
+
+	    TP_STRUCT__entry(
+		    __field(unsigned int,			obj	)
+		    __field(unsigned int,			backer	)
+		    __field(size_t,				len	)
+		    __field(loff_t,				start	)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->obj	= obj->debug_id;
+		    __entry->backer	= backer->i_ino;
+		    __entry->start	= start;
+		    __entry->len	= len;
+			   ),
+
+	    TP_printk("o=%08x b=%08x s=%llx l=%zx",
+		      __entry->obj,
+		      __entry->backer,
+		      __entry->start,
+		      __entry->len)
+	    );
+
+TRACE_EVENT(cachefiles_trunc,
+	    TP_PROTO(struct cachefiles_object *obj, struct inode *backer,
+		     loff_t from, loff_t to, enum cachefiles_trunc_trace why),
+
+	    TP_ARGS(obj, backer, from, to, why),
+
+	    TP_STRUCT__entry(
+		    __field(unsigned int,			obj	)
+		    __field(unsigned int,			backer	)
+		    __field(enum cachefiles_trunc_trace,	why	)
+		    __field(loff_t,				from	)
+		    __field(loff_t,				to	)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->obj	= obj->debug_id;
+		    __entry->backer	= backer->i_ino;
+		    __entry->from	= from;
+		    __entry->to		= to;
+		    __entry->why	= why;
+			   ),
+
+	    TP_printk("o=%08x b=%08x %s l=%llx->%llx",
+		      __entry->obj,
+		      __entry->backer,
+		      __print_symbolic(__entry->why, cachefiles_trunc_traces),
+		      __entry->from,
+		      __entry->to)
+	    );
+
+TRACE_EVENT(cachefiles_mark_active,
 	    TP_PROTO(struct cachefiles_object *obj,
-		     struct dentry *de,
 		     struct inode *inode),
 
-	    TP_ARGS(obj, de, inode),
+	    TP_ARGS(obj, inode),
 
 	    /* Note that obj may be NULL */
 	    TP_STRUCT__entry(
 		    __field(unsigned int,		obj		)
-		    __field(struct dentry *,		de		)
-		    __field(struct inode *,		inode		)
+		    __field(ino_t,			inode		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->obj	= obj->fscache.debug_id;
-		    __entry->de		= de;
-		    __entry->inode	= inode;
+		    __entry->obj	= obj ? obj->debug_id : 0;
+		    __entry->inode	= inode->i_ino;
 			   ),
 
-	    TP_printk("o=%08x d=%p i=%p",
-		      __entry->obj, __entry->de, __entry->inode)
+	    TP_printk("o=%08x i=%lx",
+		      __entry->obj, __entry->inode)
 	    );
 
-TRACE_EVENT(cachefiles_mark_buried,
+TRACE_EVENT(cachefiles_mark_inactive,
 	    TP_PROTO(struct cachefiles_object *obj,
-		     struct dentry *de,
-		     enum fscache_why_object_killed why),
+		     struct inode *inode),
 
-	    TP_ARGS(obj, de, why),
+	    TP_ARGS(obj, inode),
 
 	    /* Note that obj may be NULL */
 	    TP_STRUCT__entry(
 		    __field(unsigned int,		obj		)
-		    __field(struct dentry *,		de		)
-		    __field(enum fscache_why_object_killed, why		)
+		    __field(ino_t,			inode		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->obj	= obj ? obj->fscache.debug_id : UINT_MAX;
-		    __entry->de		= de;
-		    __entry->why	= why;
+		    __entry->obj	= obj ? obj->debug_id : 0;
+		    __entry->inode	= inode->i_ino;
 			   ),
 
-	    TP_printk("o=%08x d=%p w=%s",
-		      __entry->obj, __entry->de,
-		      __print_symbolic(__entry->why, cachefiles_obj_kill_traces))
+	    TP_printk("o=%08x i=%lx",
+		      __entry->obj, __entry->inode)
+	    );
+
+TRACE_EVENT(cachefiles_vfs_error,
+	    TP_PROTO(struct cachefiles_object *obj, struct inode *backer,
+		     int error, enum cachefiles_error_trace where),
+
+	    TP_ARGS(obj, backer, error, where),
+
+	    TP_STRUCT__entry(
+		    __field(unsigned int,			obj	)
+		    __field(unsigned int,			backer	)
+		    __field(enum cachefiles_error_trace,	where	)
+		    __field(short,				error	)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->obj	= obj ? obj->debug_id : 0;
+		    __entry->backer	= backer->i_ino;
+		    __entry->error	= error;
+		    __entry->where	= where;
+			   ),
+
+	    TP_printk("o=%08x b=%08x %s e=%d",
+		      __entry->obj,
+		      __entry->backer,
+		      __print_symbolic(__entry->where, cachefiles_error_traces),
+		      __entry->error)
+	    );
+
+TRACE_EVENT(cachefiles_io_error,
+	    TP_PROTO(struct cachefiles_object *obj, struct inode *backer,
+		     int error, enum cachefiles_error_trace where),
+
+	    TP_ARGS(obj, backer, error, where),
+
+	    TP_STRUCT__entry(
+		    __field(unsigned int,			obj	)
+		    __field(unsigned int,			backer	)
+		    __field(enum cachefiles_error_trace,	where	)
+		    __field(short,				error	)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->obj	= obj ? obj->debug_id : 0;
+		    __entry->backer	= backer->i_ino;
+		    __entry->error	= error;
+		    __entry->where	= where;
+			   ),
+
+	    TP_printk("o=%08x b=%08x %s e=%d",
+		      __entry->obj,
+		      __entry->backer,
+		      __print_symbolic(__entry->where, cachefiles_error_traces),
+		      __entry->error)
 	    );
 
 #endif /* _TRACE_CACHEFILES_H */
diff --git a/include/trace/events/fscache.h b/include/trace/events/fscache.h
index 446392f5ba83..cb3fb337e880 100644
--- a/include/trace/events/fscache.h
+++ b/include/trace/events/fscache.h
@@ -1,7 +1,7 @@
 /* SPDX-License-Identifier: GPL-2.0-or-later */
 /* FS-Cache tracepoints
  *
- * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved.
+ * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
  * Written by David Howells (dhowells@redhat.com)
  */
 #undef TRACE_SYSTEM
@@ -19,65 +19,83 @@
 #ifndef __FSCACHE_DECLARE_TRACE_ENUMS_ONCE_ONLY
 #define __FSCACHE_DECLARE_TRACE_ENUMS_ONCE_ONLY
 
+enum fscache_cache_trace {
+	fscache_cache_collision,
+	fscache_cache_get_acquire,
+	fscache_cache_new_acquire,
+	fscache_cache_put_alloc_volume,
+	fscache_cache_put_cache,
+	fscache_cache_put_prep_failed,
+	fscache_cache_put_relinquish,
+	fscache_cache_put_volume,
+};
+
+enum fscache_volume_trace {
+	fscache_volume_collision,
+	fscache_volume_get_cookie,
+	fscache_volume_get_create_work,
+	fscache_volume_get_hash_collision,
+	fscache_volume_free,
+	fscache_volume_new_acquire,
+	fscache_volume_put_cookie,
+	fscache_volume_put_create_work,
+	fscache_volume_put_hash_collision,
+	fscache_volume_put_relinquish,
+	fscache_volume_see_create_work,
+	fscache_volume_see_hash_wake,
+	fscache_volume_wait_create_work,
+};
+
 enum fscache_cookie_trace {
 	fscache_cookie_collision,
 	fscache_cookie_discard,
-	fscache_cookie_get_acquire_parent,
 	fscache_cookie_get_attach_object,
-	fscache_cookie_get_reacquire,
-	fscache_cookie_get_register_netfs,
-	fscache_cookie_put_acquire_nobufs,
-	fscache_cookie_put_dup_netfs,
-	fscache_cookie_put_relinquish,
+	fscache_cookie_get_end_access,
+	fscache_cookie_get_hash_collision,
+	fscache_cookie_get_inval_work,
+	fscache_cookie_get_lru,
+	fscache_cookie_get_use_work,
+	fscache_cookie_new_acquire,
+	fscache_cookie_put_hash_collision,
+	fscache_cookie_put_lru,
 	fscache_cookie_put_object,
-	fscache_cookie_put_parent,
-};
-
-enum fscache_page_trace {
-	fscache_page_cached,
-	fscache_page_inval,
-	fscache_page_maybe_release,
-	fscache_page_radix_clear_store,
-	fscache_page_radix_delete,
-	fscache_page_radix_insert,
-	fscache_page_radix_pend2store,
-	fscache_page_radix_set_pend,
-	fscache_page_uncache,
-	fscache_page_write,
-	fscache_page_write_end,
-	fscache_page_write_end_pend,
-	fscache_page_write_end_noc,
-	fscache_page_write_wait,
-	fscache_page_trace__nr
+	fscache_cookie_put_over_queued,
+	fscache_cookie_put_relinquish,
+	fscache_cookie_put_withdrawn,
+	fscache_cookie_put_work,
+	fscache_cookie_see_active,
+	fscache_cookie_see_lru_discard,
+	fscache_cookie_see_lru_do_one,
+	fscache_cookie_see_relinquish,
+	fscache_cookie_see_withdraw,
+	fscache_cookie_see_work,
 };
 
-enum fscache_op_trace {
-	fscache_op_cancel,
-	fscache_op_cancel_all,
-	fscache_op_cancelled,
-	fscache_op_completed,
-	fscache_op_enqueue_async,
-	fscache_op_enqueue_mythread,
-	fscache_op_gc,
-	fscache_op_init,
-	fscache_op_put,
-	fscache_op_run,
-	fscache_op_signal,
-	fscache_op_submit,
-	fscache_op_submit_ex,
-	fscache_op_work,
-	fscache_op_trace__nr
+enum fscache_active_trace {
+	fscache_active_use,
+	fscache_active_use_modify,
+	fscache_active_unuse,
 };
 
-enum fscache_page_op_trace {
-	fscache_page_op_alloc_one,
-	fscache_page_op_attr_changed,
-	fscache_page_op_check_consistency,
-	fscache_page_op_invalidate,
-	fscache_page_op_retr_multi,
-	fscache_page_op_retr_one,
-	fscache_page_op_write_one,
-	fscache_page_op_trace__nr
+enum fscache_access_trace {
+	fscache_access_acquire_volume,
+	fscache_access_acquire_volume_end,
+	fscache_access_cache_pin,
+	fscache_access_cache_unpin,
+	fscache_access_invalidate_cookie,
+	fscache_access_invalidate_cookie_end,
+	fscache_access_io_end,
+	fscache_access_io_not_live,
+	fscache_access_io_read,
+	fscache_access_io_resize,
+	fscache_access_io_wait,
+	fscache_access_io_write,
+	fscache_access_lookup_cookie,
+	fscache_access_lookup_cookie_end,
+	fscache_access_lookup_cookie_end_failed,
+	fscache_access_relinquish_volume,
+	fscache_access_relinquish_volume_end,
+	fscache_access_unlive,
 };
 
 #endif
@@ -85,59 +103,79 @@ enum fscache_page_op_trace {
 /*
  * Declare tracing information enums and their string mappings for display.
  */
+#define fscache_cache_traces						\
+	EM(fscache_cache_collision,		"*COLLIDE*")		\
+	EM(fscache_cache_get_acquire,		"GET acq  ")		\
+	EM(fscache_cache_new_acquire,		"NEW acq  ")		\
+	EM(fscache_cache_put_alloc_volume,	"PUT alvol")		\
+	EM(fscache_cache_put_cache,		"PUT cache")		\
+	EM(fscache_cache_put_prep_failed,	"PUT pfail")		\
+	EM(fscache_cache_put_relinquish,	"PUT relnq")		\
+	E_(fscache_cache_put_volume,		"PUT vol  ")
+
+#define fscache_volume_traces						\
+	EM(fscache_volume_collision,		"*COLLIDE*")		\
+	EM(fscache_volume_get_cookie,		"GET cook ")		\
+	EM(fscache_volume_get_create_work,	"GET creat")		\
+	EM(fscache_volume_get_hash_collision,	"GET hcoll")		\
+	EM(fscache_volume_free,			"FREE     ")		\
+	EM(fscache_volume_new_acquire,		"NEW acq  ")		\
+	EM(fscache_volume_put_cookie,		"PUT cook ")		\
+	EM(fscache_volume_put_create_work,	"PUT creat")		\
+	EM(fscache_volume_put_hash_collision,	"PUT hcoll")		\
+	EM(fscache_volume_put_relinquish,	"PUT relnq")		\
+	EM(fscache_volume_see_create_work,	"SEE creat")		\
+	EM(fscache_volume_see_hash_wake,	"SEE hwake")		\
+	E_(fscache_volume_wait_create_work,	"WAIT crea")
+
 #define fscache_cookie_traces						\
-	EM(fscache_cookie_collision,		"*COLLISION*")		\
-	EM(fscache_cookie_discard,		"DISCARD")		\
-	EM(fscache_cookie_get_acquire_parent,	"GET prn")		\
-	EM(fscache_cookie_get_attach_object,	"GET obj")		\
-	EM(fscache_cookie_get_reacquire,	"GET raq")		\
-	EM(fscache_cookie_get_register_netfs,	"GET net")		\
-	EM(fscache_cookie_put_acquire_nobufs,	"PUT nbf")		\
-	EM(fscache_cookie_put_dup_netfs,	"PUT dnt")		\
-	EM(fscache_cookie_put_relinquish,	"PUT rlq")		\
-	EM(fscache_cookie_put_object,		"PUT obj")		\
-	E_(fscache_cookie_put_parent,		"PUT prn")
-
-#define fscache_page_traces						\
-	EM(fscache_page_cached,			"Cached ")		\
-	EM(fscache_page_inval,			"InvalPg")		\
-	EM(fscache_page_maybe_release,		"MayRels")		\
-	EM(fscache_page_uncache,		"Uncache")		\
-	EM(fscache_page_radix_clear_store,	"RxCStr ")		\
-	EM(fscache_page_radix_delete,		"RxDel  ")		\
-	EM(fscache_page_radix_insert,		"RxIns  ")		\
-	EM(fscache_page_radix_pend2store,	"RxP2S  ")		\
-	EM(fscache_page_radix_set_pend,		"RxSPend ")		\
-	EM(fscache_page_write,			"WritePg")		\
-	EM(fscache_page_write_end,		"EndPgWr")		\
-	EM(fscache_page_write_end_pend,		"EndPgWP")		\
-	EM(fscache_page_write_end_noc,		"EndPgNC")		\
-	E_(fscache_page_write_wait,		"WtOnWrt")
-
-#define fscache_op_traces						\
-	EM(fscache_op_cancel,			"Cancel1")		\
-	EM(fscache_op_cancel_all,		"CancelA")		\
-	EM(fscache_op_cancelled,		"Canclld")		\
-	EM(fscache_op_completed,		"Complet")		\
-	EM(fscache_op_enqueue_async,		"EnqAsyn")		\
-	EM(fscache_op_enqueue_mythread,		"EnqMyTh")		\
-	EM(fscache_op_gc,			"GC     ")		\
-	EM(fscache_op_init,			"Init   ")		\
-	EM(fscache_op_put,			"Put    ")		\
-	EM(fscache_op_run,			"Run    ")		\
-	EM(fscache_op_signal,			"Signal ")		\
-	EM(fscache_op_submit,			"Submit ")		\
-	EM(fscache_op_submit_ex,		"SubmitX")		\
-	E_(fscache_op_work,			"Work   ")
-
-#define fscache_page_op_traces						\
-	EM(fscache_page_op_alloc_one,		"Alloc1 ")		\
-	EM(fscache_page_op_attr_changed,	"AttrChg")		\
-	EM(fscache_page_op_check_consistency,	"CheckCn")		\
-	EM(fscache_page_op_invalidate,		"Inval  ")		\
-	EM(fscache_page_op_retr_multi,		"RetrMul")		\
-	EM(fscache_page_op_retr_one,		"Retr1  ")		\
-	E_(fscache_page_op_write_one,		"Write1 ")
+	EM(fscache_cookie_collision,		"*COLLIDE*")		\
+	EM(fscache_cookie_discard,		"DISCARD  ")		\
+	EM(fscache_cookie_get_attach_object,	"GET attch")		\
+	EM(fscache_cookie_get_hash_collision,	"GET hcoll")		\
+	EM(fscache_cookie_get_end_access,	"GQ  endac")		\
+	EM(fscache_cookie_get_inval_work,	"GQ  inval")		\
+	EM(fscache_cookie_get_lru,		"GET lru  ")		\
+	EM(fscache_cookie_get_use_work,		"GQ  use  ")		\
+	EM(fscache_cookie_new_acquire,		"NEW acq  ")		\
+	EM(fscache_cookie_put_hash_collision,	"PUT hcoll")		\
+	EM(fscache_cookie_put_lru,		"PUT lru  ")		\
+	EM(fscache_cookie_put_object,		"PUT obj  ")		\
+	EM(fscache_cookie_put_over_queued,	"PQ  overq")		\
+	EM(fscache_cookie_put_relinquish,	"PUT relnq")		\
+	EM(fscache_cookie_put_withdrawn,	"PUT wthdn")		\
+	EM(fscache_cookie_put_work,		"PQ  work ")		\
+	EM(fscache_cookie_see_active,		"-   activ")		\
+	EM(fscache_cookie_see_lru_discard,	"-   x-lru")		\
+	EM(fscache_cookie_see_lru_do_one,	"-   lrudo")		\
+	EM(fscache_cookie_see_relinquish,	"-   x-rlq")		\
+	EM(fscache_cookie_see_withdraw,		"-   x-wth")		\
+	E_(fscache_cookie_see_work,		"-   work ")
+
+#define fscache_active_traces		\
+	EM(fscache_active_use,			"USE          ")	\
+	EM(fscache_active_use_modify,		"USE-m        ")	\
+	E_(fscache_active_unuse,		"UNUSE        ")
+
+#define fscache_access_traces		\
+	EM(fscache_access_acquire_volume,	"BEGIN acq_vol")	\
+	EM(fscache_access_acquire_volume_end,	"END   acq_vol")	\
+	EM(fscache_access_cache_pin,		"PIN   cache  ")	\
+	EM(fscache_access_cache_unpin,		"UNPIN cache  ")	\
+	EM(fscache_access_invalidate_cookie,	"BEGIN inval  ")	\
+	EM(fscache_access_invalidate_cookie_end,"END   inval  ")	\
+	EM(fscache_access_io_end,		"END   io     ")	\
+	EM(fscache_access_io_not_live,		"END   io_notl")	\
+	EM(fscache_access_io_read,		"BEGIN io_read")	\
+	EM(fscache_access_io_resize,		"BEGIN io_resz")	\
+	EM(fscache_access_io_wait,		"WAIT  io     ")	\
+	EM(fscache_access_io_write,		"BEGIN io_writ")	\
+	EM(fscache_access_lookup_cookie,	"BEGIN lookup ")	\
+	EM(fscache_access_lookup_cookie_end,	"END   lookup ")	\
+	EM(fscache_access_lookup_cookie_end_failed,"END   lookupf")	\
+	EM(fscache_access_relinquish_volume,	"BEGIN rlq_vol")	\
+	EM(fscache_access_relinquish_volume_end,"END   rlq_vol")	\
+	E_(fscache_access_unlive,		"END   unlive ")
 
 /*
  * Export enum symbols via userspace.
@@ -147,7 +185,10 @@ enum fscache_page_op_trace {
 #define EM(a, b) TRACE_DEFINE_ENUM(a);
 #define E_(a, b) TRACE_DEFINE_ENUM(a);
 
+fscache_cache_traces;
+fscache_volume_traces;
 fscache_cookie_traces;
+fscache_access_traces;
 
 /*
  * Now redefine the EM() and E_() macros to map the enums to the strings that
@@ -159,362 +200,297 @@ fscache_cookie_traces;
 #define E_(a, b)	{ a, b }
 
 
-TRACE_EVENT(fscache_cookie,
-	    TP_PROTO(unsigned int cookie_debug_id,
-		     int ref,
-		     enum fscache_cookie_trace where),
+TRACE_EVENT(fscache_cache,
+	    TP_PROTO(unsigned int cache_debug_id,
+		     int usage,
+		     enum fscache_cache_trace where),
 
-	    TP_ARGS(cookie_debug_id, ref, where),
+	    TP_ARGS(cache_debug_id, usage, where),
 
 	    TP_STRUCT__entry(
-		    __field(unsigned int,		cookie		)
-		    __field(enum fscache_cookie_trace,	where		)
-		    __field(int,			ref		)
+		    __field(unsigned int,		cache		)
+		    __field(int,			usage		)
+		    __field(enum fscache_cache_trace,	where		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie	= cookie_debug_id;
+		    __entry->cache	= cache_debug_id;
+		    __entry->usage	= usage;
 		    __entry->where	= where;
-		    __entry->ref	= ref;
 			   ),
 
-	    TP_printk("%s c=%08x r=%d",
-		      __print_symbolic(__entry->where, fscache_cookie_traces),
-		      __entry->cookie, __entry->ref)
+	    TP_printk("C=%08x %s r=%d",
+		      __entry->cache,
+		      __print_symbolic(__entry->where, fscache_cache_traces),
+		      __entry->usage)
 	    );
 
-TRACE_EVENT(fscache_netfs,
-	    TP_PROTO(struct fscache_netfs *netfs),
+TRACE_EVENT(fscache_volume,
+	    TP_PROTO(unsigned int volume_debug_id,
+		     int usage,
+		     enum fscache_volume_trace where),
 
-	    TP_ARGS(netfs),
-
-	    TP_STRUCT__entry(
-		    __field(unsigned int,		cookie		)
-		    __array(char,			name, 8		)
-			     ),
-
-	    TP_fast_assign(
-		    __entry->cookie		= netfs->primary_index->debug_id;
-		    strncpy(__entry->name, netfs->name, 8);
-		    __entry->name[7]		= 0;
-			   ),
-
-	    TP_printk("c=%08x n=%s",
-		      __entry->cookie, __entry->name)
-	    );
-
-TRACE_EVENT(fscache_acquire,
-	    TP_PROTO(struct fscache_cookie *cookie),
-
-	    TP_ARGS(cookie),
+	    TP_ARGS(volume_debug_id, usage, where),
 
 	    TP_STRUCT__entry(
-		    __field(unsigned int,		cookie		)
-		    __field(unsigned int,		parent		)
-		    __array(char,			name, 8		)
-		    __field(int,			p_ref		)
-		    __field(int,			p_n_children	)
-		    __field(u8,				p_flags		)
+		    __field(unsigned int,		volume		)
+		    __field(int,			usage		)
+		    __field(enum fscache_volume_trace,	where		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie		= cookie->debug_id;
-		    __entry->parent		= cookie->parent->debug_id;
-		    __entry->p_ref		= refcount_read(&cookie->parent->ref);
-		    __entry->p_n_children	= atomic_read(&cookie->parent->n_children);
-		    __entry->p_flags		= cookie->parent->flags;
-		    memcpy(__entry->name, cookie->def->name, 8);
-		    __entry->name[7]		= 0;
+		    __entry->volume	= volume_debug_id;
+		    __entry->usage	= usage;
+		    __entry->where	= where;
 			   ),
 
-	    TP_printk("c=%08x p=%08x pr=%d pc=%d pf=%02x n=%s",
-		      __entry->cookie, __entry->parent, __entry->p_ref,
-		      __entry->p_n_children, __entry->p_flags, __entry->name)
+	    TP_printk("V=%08x %s u=%d",
+		      __entry->volume,
+		      __print_symbolic(__entry->where, fscache_volume_traces),
+		      __entry->usage)
 	    );
 
-TRACE_EVENT(fscache_relinquish,
-	    TP_PROTO(struct fscache_cookie *cookie, bool retire),
+TRACE_EVENT(fscache_cookie,
+	    TP_PROTO(unsigned int cookie_debug_id,
+		     int ref,
+		     enum fscache_cookie_trace where),
 
-	    TP_ARGS(cookie, retire),
+	    TP_ARGS(cookie_debug_id, ref, where),
 
 	    TP_STRUCT__entry(
 		    __field(unsigned int,		cookie		)
-		    __field(unsigned int,		parent		)
 		    __field(int,			ref		)
-		    __field(int,			n_children	)
-		    __field(int,			n_active	)
-		    __field(u8,				flags		)
-		    __field(bool,			retire		)
+		    __field(enum fscache_cookie_trace,	where		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie	= cookie->debug_id;
-		    __entry->parent	= cookie->parent->debug_id;
-		    __entry->ref	= refcount_read(&cookie->ref);
-		    __entry->n_children	= atomic_read(&cookie->n_children);
-		    __entry->n_active	= atomic_read(&cookie->n_active);
-		    __entry->flags	= cookie->flags;
-		    __entry->retire	= retire;
+		    __entry->cookie	= cookie_debug_id;
+		    __entry->ref	= ref;
+		    __entry->where	= where;
 			   ),
 
-	    TP_printk("c=%08x r=%d p=%08x Nc=%d Na=%d f=%02x r=%u",
-		      __entry->cookie, __entry->ref,
-		      __entry->parent, __entry->n_children, __entry->n_active,
-		      __entry->flags, __entry->retire)
+	    TP_printk("c=%08x %s r=%d",
+		      __entry->cookie,
+		      __print_symbolic(__entry->where, fscache_cookie_traces),
+		      __entry->ref)
 	    );
 
-TRACE_EVENT(fscache_enable,
-	    TP_PROTO(struct fscache_cookie *cookie),
+TRACE_EVENT(fscache_active,
+	    TP_PROTO(unsigned int cookie_debug_id,
+		     int ref,
+		     int n_active,
+		     int n_accesses,
+		     enum fscache_active_trace why),
 
-	    TP_ARGS(cookie),
+	    TP_ARGS(cookie_debug_id, ref, n_active, n_accesses, why),
 
 	    TP_STRUCT__entry(
 		    __field(unsigned int,		cookie		)
 		    __field(int,			ref		)
-		    __field(int,			n_children	)
 		    __field(int,			n_active	)
-		    __field(u8,				flags		)
+		    __field(int,			n_accesses	)
+		    __field(enum fscache_active_trace,	why		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie	= cookie->debug_id;
-		    __entry->ref	= refcount_read(&cookie->ref);
-		    __entry->n_children	= atomic_read(&cookie->n_children);
-		    __entry->n_active	= atomic_read(&cookie->n_active);
-		    __entry->flags	= cookie->flags;
+		    __entry->cookie	= cookie_debug_id;
+		    __entry->ref	= ref;
+		    __entry->n_active	= n_active;
+		    __entry->n_accesses	= n_accesses;
+		    __entry->why	= why;
 			   ),
 
-	    TP_printk("c=%08x r=%d Nc=%d Na=%d f=%02x",
-		      __entry->cookie, __entry->ref,
-		      __entry->n_children, __entry->n_active, __entry->flags)
+	    TP_printk("c=%08x %s r=%d a=%d c=%d",
+		      __entry->cookie,
+		      __print_symbolic(__entry->why, fscache_active_traces),
+		      __entry->ref,
+		      __entry->n_accesses,
+		      __entry->n_active)
 	    );
 
-TRACE_EVENT(fscache_disable,
-	    TP_PROTO(struct fscache_cookie *cookie),
+TRACE_EVENT(fscache_access_cache,
+	    TP_PROTO(unsigned int cache_debug_id,
+		     int ref,
+		     int n_accesses,
+		     enum fscache_access_trace why),
 
-	    TP_ARGS(cookie),
+	    TP_ARGS(cache_debug_id, ref, n_accesses, why),
 
 	    TP_STRUCT__entry(
-		    __field(unsigned int,		cookie		)
+		    __field(unsigned int,		cache		)
 		    __field(int,			ref		)
-		    __field(int,			n_children	)
-		    __field(int,			n_active	)
-		    __field(u8,				flags		)
+		    __field(int,			n_accesses	)
+		    __field(enum fscache_access_trace,	why		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie	= cookie->debug_id;
-		    __entry->ref	= refcount_read(&cookie->ref);
-		    __entry->n_children	= atomic_read(&cookie->n_children);
-		    __entry->n_active	= atomic_read(&cookie->n_active);
-		    __entry->flags	= cookie->flags;
+		    __entry->cache	= cache_debug_id;
+		    __entry->ref	= ref;
+		    __entry->n_accesses	= n_accesses;
+		    __entry->why	= why;
 			   ),
 
-	    TP_printk("c=%08x r=%d Nc=%d Na=%d f=%02x",
-		      __entry->cookie, __entry->ref,
-		      __entry->n_children, __entry->n_active, __entry->flags)
+	    TP_printk("C=%08x %s r=%d a=%d",
+		      __entry->cache,
+		      __print_symbolic(__entry->why, fscache_access_traces),
+		      __entry->ref,
+		      __entry->n_accesses)
 	    );
 
-TRACE_EVENT(fscache_osm,
-	    TP_PROTO(struct fscache_object *object,
-		     const struct fscache_state *state,
-		     bool wait, bool oob, s8 event_num),
+TRACE_EVENT(fscache_access_volume,
+	    TP_PROTO(unsigned int volume_debug_id,
+		     unsigned int cookie_debug_id,
+		     int ref,
+		     int n_accesses,
+		     enum fscache_access_trace why),
 
-	    TP_ARGS(object, state, wait, oob, event_num),
+	    TP_ARGS(volume_debug_id, cookie_debug_id, ref, n_accesses, why),
 
 	    TP_STRUCT__entry(
+		    __field(unsigned int,		volume		)
 		    __field(unsigned int,		cookie		)
-		    __field(unsigned int,		object		)
-		    __array(char,			state, 8	)
-		    __field(bool,			wait		)
-		    __field(bool,			oob		)
-		    __field(s8,				event_num	)
+		    __field(int,			ref		)
+		    __field(int,			n_accesses	)
+		    __field(enum fscache_access_trace,	why		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie		= object->cookie->debug_id;
-		    __entry->object		= object->debug_id;
-		    __entry->wait		= wait;
-		    __entry->oob		= oob;
-		    __entry->event_num		= event_num;
-		    memcpy(__entry->state, state->short_name, 8);
+		    __entry->volume	= volume_debug_id;
+		    __entry->cookie	= cookie_debug_id;
+		    __entry->ref	= ref;
+		    __entry->n_accesses	= n_accesses;
+		    __entry->why	= why;
 			   ),
 
-	    TP_printk("c=%08x o=%08d %s %s%sev=%d",
+	    TP_printk("V=%08x c=%08x %s r=%d a=%d",
+		      __entry->volume,
 		      __entry->cookie,
-		      __entry->object,
-		      __entry->state,
-		      __print_symbolic(__entry->wait,
-				       { true,  "WAIT" },
-				       { false, "WORK" }),
-		      __print_symbolic(__entry->oob,
-				       { true,  " OOB " },
-				       { false, " " }),
-		      __entry->event_num)
+		      __print_symbolic(__entry->why, fscache_access_traces),
+		      __entry->ref,
+		      __entry->n_accesses)
 	    );
 
-TRACE_EVENT(fscache_page,
-	    TP_PROTO(struct fscache_cookie *cookie, struct page *page,
-		     enum fscache_page_trace why),
+TRACE_EVENT(fscache_access,
+	    TP_PROTO(unsigned int cookie_debug_id,
+		     int ref,
+		     int n_accesses,
+		     enum fscache_access_trace why),
 
-	    TP_ARGS(cookie, page, why),
+	    TP_ARGS(cookie_debug_id, ref, n_accesses, why),
 
 	    TP_STRUCT__entry(
 		    __field(unsigned int,		cookie		)
-		    __field(pgoff_t,			page		)
-		    __field(enum fscache_page_trace,	why		)
+		    __field(int,			ref		)
+		    __field(int,			n_accesses	)
+		    __field(enum fscache_access_trace,	why		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie		= cookie->debug_id;
-		    __entry->page		= page->index;
-		    __entry->why		= why;
+		    __entry->cookie	= cookie_debug_id;
+		    __entry->ref	= ref;
+		    __entry->n_accesses	= n_accesses;
+		    __entry->why	= why;
 			   ),
 
-	    TP_printk("c=%08x %s pg=%lx",
+	    TP_printk("c=%08x %s r=%d a=%d",
 		      __entry->cookie,
-		      __print_symbolic(__entry->why, fscache_page_traces),
-		      __entry->page)
-	    );
-
-TRACE_EVENT(fscache_check_page,
-	    TP_PROTO(struct fscache_cookie *cookie, struct page *page,
-		     void *val, int n),
-
-	    TP_ARGS(cookie, page, val, n),
-
-	    TP_STRUCT__entry(
-		    __field(unsigned int,		cookie		)
-		    __field(void *,			page		)
-		    __field(void *,			val		)
-		    __field(int,			n		)
-			     ),
-
-	    TP_fast_assign(
-		    __entry->cookie		= cookie->debug_id;
-		    __entry->page		= page;
-		    __entry->val		= val;
-		    __entry->n			= n;
-			   ),
-
-	    TP_printk("c=%08x pg=%p val=%p n=%d",
-		      __entry->cookie, __entry->page, __entry->val, __entry->n)
+		      __print_symbolic(__entry->why, fscache_access_traces),
+		      __entry->ref,
+		      __entry->n_accesses)
 	    );
 
-TRACE_EVENT(fscache_wake_cookie,
+TRACE_EVENT(fscache_acquire,
 	    TP_PROTO(struct fscache_cookie *cookie),
 
 	    TP_ARGS(cookie),
 
 	    TP_STRUCT__entry(
 		    __field(unsigned int,		cookie		)
+		    __field(unsigned int,		volume		)
+		    __field(int,			v_ref		)
+		    __field(int,			v_n_cookies	)
 			     ),
 
 	    TP_fast_assign(
 		    __entry->cookie		= cookie->debug_id;
+		    __entry->volume		= cookie->volume->debug_id;
+		    __entry->v_ref		= refcount_read(&cookie->volume->ref);
+		    __entry->v_n_cookies	= atomic_read(&cookie->volume->n_cookies);
 			   ),
 
-	    TP_printk("c=%08x", __entry->cookie)
-	    );
-
-TRACE_EVENT(fscache_op,
-	    TP_PROTO(struct fscache_cookie *cookie, struct fscache_operation *op,
-		     enum fscache_op_trace why),
-
-	    TP_ARGS(cookie, op, why),
-
-	    TP_STRUCT__entry(
-		    __field(unsigned int,		cookie		)
-		    __field(unsigned int,		op		)
-		    __field(enum fscache_op_trace,	why		)
-			     ),
-
-	    TP_fast_assign(
-		    __entry->cookie		= cookie ? cookie->debug_id : 0;
-		    __entry->op			= op->debug_id;
-		    __entry->why		= why;
-			   ),
-
-	    TP_printk("c=%08x op=%08x %s",
-		      __entry->cookie, __entry->op,
-		      __print_symbolic(__entry->why, fscache_op_traces))
+	    TP_printk("c=%08x V=%08x vr=%d vc=%d",
+		      __entry->cookie,
+		      __entry->volume, __entry->v_ref, __entry->v_n_cookies)
 	    );
 
-TRACE_EVENT(fscache_page_op,
-	    TP_PROTO(struct fscache_cookie *cookie, struct page *page,
-		     struct fscache_operation *op, enum fscache_page_op_trace what),
+TRACE_EVENT(fscache_relinquish,
+	    TP_PROTO(struct fscache_cookie *cookie, bool retire),
 
-	    TP_ARGS(cookie, page, op, what),
+	    TP_ARGS(cookie, retire),
 
 	    TP_STRUCT__entry(
 		    __field(unsigned int,		cookie		)
-		    __field(unsigned int,		op		)
-		    __field(pgoff_t,			page		)
-		    __field(enum fscache_page_op_trace,	what		)
+		    __field(unsigned int,		volume		)
+		    __field(int,			ref		)
+		    __field(int,			n_active	)
+		    __field(u8,				flags		)
+		    __field(bool,			retire		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie		= cookie->debug_id;
-		    __entry->page		= page ? page->index : 0;
-		    __entry->op			= op->debug_id;
-		    __entry->what		= what;
+		    __entry->cookie	= cookie->debug_id;
+		    __entry->volume	= cookie->volume->debug_id;
+		    __entry->ref	= refcount_read(&cookie->ref);
+		    __entry->n_active	= atomic_read(&cookie->n_active);
+		    __entry->flags	= cookie->flags;
+		    __entry->retire	= retire;
 			   ),
 
-	    TP_printk("c=%08x %s pg=%lx op=%08x",
-		      __entry->cookie,
-		      __print_symbolic(__entry->what, fscache_page_op_traces),
-		      __entry->page, __entry->op)
+	    TP_printk("c=%08x V=%08x r=%d U=%d f=%02x rt=%u",
+		      __entry->cookie, __entry->volume, __entry->ref,
+		      __entry->n_active, __entry->flags, __entry->retire)
 	    );
 
-TRACE_EVENT(fscache_wrote_page,
-	    TP_PROTO(struct fscache_cookie *cookie, struct page *page,
-		     struct fscache_operation *op, int ret),
+TRACE_EVENT(fscache_invalidate,
+	    TP_PROTO(struct fscache_cookie *cookie, loff_t new_size),
 
-	    TP_ARGS(cookie, page, op, ret),
+	    TP_ARGS(cookie, new_size),
 
 	    TP_STRUCT__entry(
 		    __field(unsigned int,		cookie		)
-		    __field(unsigned int,		op		)
-		    __field(pgoff_t,			page		)
-		    __field(int,			ret		)
+		    __field(loff_t,			new_size	)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie		= cookie->debug_id;
-		    __entry->page		= page->index;
-		    __entry->op			= op->debug_id;
-		    __entry->ret		= ret;
+		    __entry->cookie	= cookie->debug_id;
+		    __entry->new_size	= new_size;
 			   ),
 
-	    TP_printk("c=%08x pg=%lx op=%08x ret=%d",
-		      __entry->cookie, __entry->page, __entry->op, __entry->ret)
+	    TP_printk("c=%08x sz=%llx",
+		      __entry->cookie, __entry->new_size)
 	    );
 
-TRACE_EVENT(fscache_gang_lookup,
-	    TP_PROTO(struct fscache_cookie *cookie, struct fscache_operation *op,
-		     void **results, int n, pgoff_t store_limit),
+TRACE_EVENT(fscache_resize,
+	    TP_PROTO(struct fscache_cookie *cookie, loff_t new_size),
 
-	    TP_ARGS(cookie, op, results, n, store_limit),
+	    TP_ARGS(cookie, new_size),
 
 	    TP_STRUCT__entry(
 		    __field(unsigned int,		cookie		)
-		    __field(unsigned int,		op		)
-		    __field(pgoff_t,			results0	)
-		    __field(int,			n		)
-		    __field(pgoff_t,			store_limit	)
+		    __field(loff_t,			old_size	)
+		    __field(loff_t,			new_size	)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie		= cookie->debug_id;
-		    __entry->op			= op->debug_id;
-		    __entry->results0		= results[0] ? ((struct page *)results[0])->index : (pgoff_t)-1;
-		    __entry->n			= n;
-		    __entry->store_limit	= store_limit;
+		    __entry->cookie	= cookie->debug_id;
+		    __entry->old_size	= cookie->object_size;
+		    __entry->new_size	= new_size;
 			   ),
 
-	    TP_printk("c=%08x op=%08x r0=%lx n=%d sl=%lx",
-		      __entry->cookie, __entry->op, __entry->results0, __entry->n,
-		      __entry->store_limit)
+	    TP_printk("c=%08x os=%08llx sz=%08llx",
+		      __entry->cookie,
+		      __entry->old_size,
+		      __entry->new_size)
 	    );
 
 #endif /* _TRACE_FSCACHE_H */
diff --git a/include/trace/events/netfs.h b/include/trace/events/netfs.h
index 4d470bffd9f1..e6f4ebbb4c69 100644
--- a/include/trace/events/netfs.h
+++ b/include/trace/events/netfs.h
@@ -135,6 +135,7 @@ TRACE_EVENT(netfs_read,
 		    __field(loff_t,			start		)
 		    __field(size_t,			len		)
 		    __field(enum netfs_read_trace,	what		)
+		    __field(unsigned int,		netfs_inode	)
 			     ),
 
 	    TP_fast_assign(
@@ -143,12 +144,14 @@ TRACE_EVENT(netfs_read,
 		    __entry->start	= start;
 		    __entry->len	= len;
 		    __entry->what	= what;
+		    __entry->netfs_inode = rreq->inode->i_ino;
 			   ),
 
-	    TP_printk("R=%08x %s c=%08x s=%llx %zx",
+	    TP_printk("R=%08x %s c=%08x ni=%x s=%llx %zx",
 		      __entry->rreq,
 		      __print_symbolic(__entry->what, netfs_read_traces),
 		      __entry->cookie,
+		      __entry->netfs_inode,
 		      __entry->start, __entry->len)
 	    );