Re: [PATCH 0/8] MUSE: Userspace backed MTD v3

[Miklos Szeredi <miklos@szeredi.hu>]

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On Tue, Feb 9, 2021 at 9:06 PM Richard Weinberger <richard@nod.at> wrote:
>
> Miklos,
>
> ----- Ursprüngliche Mail -----
> >> I do wonder if MUSE should go to drivers/mtd/ instead.   Long term
> >> goal would be move CUSE to drivers/char and move the transport part of
> >> fuse into net/fuse leaving only the actual filesystems (fuse and
> >> virtiofs) under fs/.
> >>
> >> But for now just moving the minimal interface needed for MUSE into a
> >> separate header (<net/fuse.h>) would work, I guess.
> >>
> >> Do you think that would make sense?
> >
> > Yes, I'm all for having MUSE in drivers/mtd/.
> >
> > I placed MUSE initially in fs/fuse/ because CUSE was already there and muse.c
> > includes
> > fuse_i.h. So tried to be as little invasive as possible.
>
> I did a quick patch series which moves CUSE into drivers/char/
>
> https://git.kernel.org/pub/scm/linux/kernel/git/rw/misc.git/log/?h=fs_fuse_split
>
> Does this more or less what you had in mind?

Just moving the whole internal header file is not nice.  I did a
mechanical public/private separation of the interface based on what
CUSE uses.   Incremental patch attached.

But this is just a start.  From the big structures still left in
<net/fuse.h> CUSE only uses the following fields:

fc: .minor, max_read, max_write, rcu, release, initialized, num_waiting
fm: .fc
ff: .fm
fud: .fc

Dealing with the last 3 is trivial:  create and alloc function for the
fm, and create accessor functions for the accessed fields.

Dealing with fc properly is probably a bit more involved, but does not
seem to be too compex at first glance.

Do you want to take a stab at cleaning this up further?

Thanks,
Miklos

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commit 6bc38f7550ccc8c18194ee42194e334c53890afc
Author: Miklos Szeredi <mszeredi@redhat.com>
Date:   Wed Feb 10 10:59:40 2021 +0100

    separate fuse_i.h from <net/fuse.h>

diff --git a/drivers/char/cuse.c b/drivers/char/cuse.c
index 02e382b9863b..c329de20180b 100644
--- a/drivers/char/cuse.c
+++ b/drivers/char/cuse.c
@@ -35,6 +35,7 @@
 #define pr_fmt(fmt) "CUSE: " fmt
 
 #include <linux/fuse.h>
+#include <linux/mm.h>
 #include <linux/cdev.h>
 #include <linux/device.h>
 #include <linux/file.h>
diff --git a/fs/fuse/acl.c b/fs/fuse/acl.c
index 008241c4c403..f529075a2ce8 100644
--- a/fs/fuse/acl.c
+++ b/fs/fuse/acl.c
@@ -6,11 +6,11 @@
  * See the file COPYING.
  */
 
+#include "fuse_i.h"
+
 #include <linux/posix_acl.h>
 #include <linux/posix_acl_xattr.h>
 
-#include <net/fuse.h>
-
 struct posix_acl *fuse_get_acl(struct inode *inode, int type)
 {
 	struct fuse_conn *fc = get_fuse_conn(inode);
diff --git a/fs/fuse/control.c b/fs/fuse/control.c
index 39d71ef076dc..cc7e94d73c6c 100644
--- a/fs/fuse/control.c
+++ b/fs/fuse/control.c
@@ -6,12 +6,12 @@
   See the file COPYING.
 */
 
+#include "fuse_i.h"
+
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/fs_context.h>
 
-#include <net/fuse.h>
-
 #define FUSE_CTL_SUPER_MAGIC 0x65735543
 
 /*
diff --git a/fs/fuse/dax.c b/fs/fuse/dax.c
index d222bef6e622..ff99ab2a3c43 100644
--- a/fs/fuse/dax.c
+++ b/fs/fuse/dax.c
@@ -4,6 +4,8 @@
  * Copyright (C) 2020 Red Hat, Inc.
  */
 
+#include "fuse_i.h"
+
 #include <linux/delay.h>
 #include <linux/dax.h>
 #include <linux/uio.h>
@@ -11,8 +13,6 @@
 #include <linux/iomap.h>
 #include <linux/interval_tree.h>
 
-#include <net/fuse.h>
-
 /*
  * Default memory range size.  A power of 2 so it agrees with common FUSE_INIT
  * map_alignment values 4KB and 64KB.
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index f2e87baa2f59..588f8d1240aa 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -6,6 +6,8 @@
   See the file COPYING.
 */
 
+#include "fuse_i.h"
+
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/poll.h>
@@ -20,8 +22,6 @@
 #include <linux/splice.h>
 #include <linux/sched.h>
 
-#include <net/fuse.h>
-
 MODULE_ALIAS_MISCDEV(FUSE_MINOR);
 MODULE_ALIAS("devname:fuse");
 
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 924c473a577b..78f9f209078c 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -6,6 +6,8 @@
   See the file COPYING.
 */
 
+#include "fuse_i.h"
+
 #include <linux/pagemap.h>
 #include <linux/file.h>
 #include <linux/fs_context.h>
@@ -16,8 +18,6 @@
 #include <linux/iversion.h>
 #include <linux/posix_acl.h>
 
-#include <net/fuse.h>
-
 static void fuse_advise_use_readdirplus(struct inode *dir)
 {
 	struct fuse_inode *fi = get_fuse_inode(dir);
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index ca49f86fb22d..8cccecb55fb8 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -6,6 +6,8 @@
   See the file COPYING.
 */
 
+#include "fuse_i.h"
+
 #include <linux/pagemap.h>
 #include <linux/slab.h>
 #include <linux/kernel.h>
@@ -18,8 +20,6 @@
 #include <linux/uio.h>
 #include <linux/fs.h>
 
-#include <net/fuse.h>
-
 static struct page **fuse_pages_alloc(unsigned int npages, gfp_t flags,
 				      struct fuse_page_desc **desc)
 {
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
new file mode 100644
index 000000000000..e8d877de6dae
--- /dev/null
+++ b/fs/fuse/fuse_i.h
@@ -0,0 +1,657 @@
+/*
+  FUSE: Filesystem in Userspace
+  Copyright (C) 2001-2008  Miklos Szeredi <miklos@szeredi.hu>
+
+  This program can be distributed under the terms of the GNU GPL.
+  See the file COPYING.
+*/
+
+#ifndef _FS_FUSE_I_H
+#define _FS_FUSE_I_H
+
+#ifndef pr_fmt
+# define pr_fmt(fmt) "fuse: " fmt
+#endif
+
+#include <net/fuse.h>
+
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/wait.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/backing-dev.h>
+#include <linux/mutex.h>
+#include <linux/rwsem.h>
+#include <linux/rbtree.h>
+#include <linux/workqueue.h>
+#include <linux/xattr.h>
+#include <linux/pid_namespace.h>
+#include <linux/refcount.h>
+#include <linux/user_namespace.h>
+
+/** Default max number of pages that can be used in a single read request */
+#define FUSE_DEFAULT_MAX_PAGES_PER_REQ 32
+
+/** Maximum of max_pages received in init_out */
+#define FUSE_MAX_MAX_PAGES 256
+
+/** Bias for fi->writectr, meaning new writepages must not be sent */
+#define FUSE_NOWRITE INT_MIN
+
+/** It could be as large as PATH_MAX, but would that have any uses? */
+#define FUSE_NAME_MAX 1024
+
+/** List of active connections */
+extern struct list_head fuse_conn_list;
+
+/** Global mutex protecting fuse_conn_list and the control filesystem */
+extern struct mutex fuse_mutex;
+
+/** Module parameters */
+extern unsigned max_user_bgreq;
+extern unsigned max_user_congthresh;
+
+/** FUSE inode */
+struct fuse_inode {
+	/** Inode data */
+	struct inode inode;
+
+	/** Unique ID, which identifies the inode between userspace
+	 * and kernel */
+	u64 nodeid;
+
+	/** Number of lookups on this inode */
+	u64 nlookup;
+
+	/** The request used for sending the FORGET message */
+	struct fuse_forget_link *forget;
+
+	/** Time in jiffies until the file attributes are valid */
+	u64 i_time;
+
+	/* Which attributes are invalid */
+	u32 inval_mask;
+
+	/** The sticky bit in inode->i_mode may have been removed, so
+	    preserve the original mode */
+	umode_t orig_i_mode;
+
+	/** 64 bit inode number */
+	u64 orig_ino;
+
+	/** Version of last attribute change */
+	u64 attr_version;
+
+	union {
+		/* Write related fields (regular file only) */
+		struct {
+			/* Files usable in writepage.  Protected by fi->lock */
+			struct list_head write_files;
+
+			/* Writepages pending on truncate or fsync */
+			struct list_head queued_writes;
+
+			/* Number of sent writes, a negative bias
+			 * (FUSE_NOWRITE) means more writes are blocked */
+			int writectr;
+
+			/* Waitq for writepage completion */
+			wait_queue_head_t page_waitq;
+
+			/* List of writepage requestst (pending or sent) */
+			struct rb_root writepages;
+		};
+
+		/* readdir cache (directory only) */
+		struct {
+			/* true if fully cached */
+			bool cached;
+
+			/* size of cache */
+			loff_t size;
+
+			/* position at end of cache (position of next entry) */
+			loff_t pos;
+
+			/* version of the cache */
+			u64 version;
+
+			/* modification time of directory when cache was
+			 * started */
+			struct timespec64 mtime;
+
+			/* iversion of directory when cache was started */
+			u64 iversion;
+
+			/* protects above fields */
+			spinlock_t lock;
+		} rdc;
+	};
+
+	/** Miscellaneous bits describing inode state */
+	unsigned long state;
+
+	/** Lock for serializing lookup and readdir for back compatibility*/
+	struct mutex mutex;
+
+	/** Lock to protect write related fields */
+	spinlock_t lock;
+
+	/**
+	 * Can't take inode lock in fault path (leads to circular dependency).
+	 * Introduce another semaphore which can be taken in fault path and
+	 * then other filesystem paths can take this to block faults.
+	 */
+	struct rw_semaphore i_mmap_sem;
+
+#ifdef CONFIG_FUSE_DAX
+	/*
+	 * Dax specific inode data
+	 */
+	struct fuse_inode_dax *dax;
+#endif
+};
+
+/** FUSE inode state bits */
+enum {
+	/** Advise readdirplus  */
+	FUSE_I_ADVISE_RDPLUS,
+	/** Initialized with readdirplus */
+	FUSE_I_INIT_RDPLUS,
+	/** An operation changing file size is in progress  */
+	FUSE_I_SIZE_UNSTABLE,
+	/* Bad inode */
+	FUSE_I_BAD,
+};
+
+/**
+ * Request flags
+ *
+ * FR_ISREPLY:		set if the request has reply
+ * FR_FORCE:		force sending of the request even if interrupted
+ * FR_BACKGROUND:	request is sent in the background
+ * FR_WAITING:		request is counted as "waiting"
+ * FR_ABORTED:		the request was aborted
+ * FR_INTERRUPTED:	the request has been interrupted
+ * FR_LOCKED:		data is being copied to/from the request
+ * FR_PENDING:		request is not yet in userspace
+ * FR_SENT:		request is in userspace, waiting for an answer
+ * FR_FINISHED:		request is finished
+ * FR_PRIVATE:		request is on private list
+ * FR_ASYNC:		request is asynchronous
+ */
+enum fuse_req_flag {
+	FR_ISREPLY,
+	FR_FORCE,
+	FR_BACKGROUND,
+	FR_WAITING,
+	FR_ABORTED,
+	FR_INTERRUPTED,
+	FR_LOCKED,
+	FR_PENDING,
+	FR_SENT,
+	FR_FINISHED,
+	FR_PRIVATE,
+	FR_ASYNC,
+};
+
+/**
+ * A request to the client
+ *
+ * .waitq.lock protects the following fields:
+ *   - FR_ABORTED
+ *   - FR_LOCKED (may also be modified under fc->lock, tested under both)
+ */
+struct fuse_req {
+	/** This can be on either pending processing or io lists in
+	    fuse_conn */
+	struct list_head list;
+
+	/** Entry on the interrupts list  */
+	struct list_head intr_entry;
+
+	/* Input/output arguments */
+	struct fuse_args *args;
+
+	/** refcount */
+	refcount_t count;
+
+	/* Request flags, updated with test/set/clear_bit() */
+	unsigned long flags;
+
+	/* The request input header */
+	struct {
+		struct fuse_in_header h;
+	} in;
+
+	/* The request output header */
+	struct {
+		struct fuse_out_header h;
+	} out;
+
+	/** Used to wake up the task waiting for completion of request*/
+	wait_queue_head_t waitq;
+
+#if IS_ENABLED(CONFIG_VIRTIO_FS)
+	/** virtio-fs's physically contiguous buffer for in and out args */
+	void *argbuf;
+#endif
+
+	/** fuse_mount this request belongs to */
+	struct fuse_mount *fm;
+};
+
+struct fuse_iqueue;
+
+/**
+ * Input queue callbacks
+ *
+ * Input queue signalling is device-specific.  For example, the /dev/fuse file
+ * uses fiq->waitq and fasync to wake processes that are waiting on queue
+ * readiness.  These callbacks allow other device types to respond to input
+ * queue activity.
+ */
+struct fuse_iqueue_ops {
+	/**
+	 * Signal that a forget has been queued
+	 */
+	void (*wake_forget_and_unlock)(struct fuse_iqueue *fiq)
+		__releases(fiq->lock);
+
+	/**
+	 * Signal that an INTERRUPT request has been queued
+	 */
+	void (*wake_interrupt_and_unlock)(struct fuse_iqueue *fiq)
+		__releases(fiq->lock);
+
+	/**
+	 * Signal that a request has been queued
+	 */
+	void (*wake_pending_and_unlock)(struct fuse_iqueue *fiq)
+		__releases(fiq->lock);
+
+	/**
+	 * Clean up when fuse_iqueue is destroyed
+	 */
+	void (*release)(struct fuse_iqueue *fiq);
+};
+
+#define FUSE_PQ_HASH_BITS 8
+#define FUSE_PQ_HASH_SIZE (1 << FUSE_PQ_HASH_BITS)
+
+struct fuse_fs_context {
+	int fd;
+	unsigned int rootmode;
+	kuid_t user_id;
+	kgid_t group_id;
+	bool is_bdev:1;
+	bool fd_present:1;
+	bool rootmode_present:1;
+	bool user_id_present:1;
+	bool group_id_present:1;
+	bool default_permissions:1;
+	bool allow_other:1;
+	bool destroy:1;
+	bool no_control:1;
+	bool no_force_umount:1;
+	bool legacy_opts_show:1;
+	bool dax:1;
+	unsigned int max_read;
+	unsigned int blksize;
+	const char *subtype;
+
+	/* DAX device, may be NULL */
+	struct dax_device *dax_dev;
+
+	/* fuse_dev pointer to fill in, should contain NULL on entry */
+	void **fudptr;
+};
+
+
+static inline struct fuse_mount *get_fuse_mount_super(struct super_block *sb)
+{
+	return sb->s_fs_info;
+}
+
+static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb)
+{
+	return get_fuse_mount_super(sb)->fc;
+}
+
+static inline struct fuse_mount *get_fuse_mount(struct inode *inode)
+{
+	return get_fuse_mount_super(inode->i_sb);
+}
+
+static inline struct fuse_conn *get_fuse_conn(struct inode *inode)
+{
+	return get_fuse_mount_super(inode->i_sb)->fc;
+}
+
+static inline struct fuse_inode *get_fuse_inode(struct inode *inode)
+{
+	return container_of(inode, struct fuse_inode, inode);
+}
+
+static inline u64 get_node_id(struct inode *inode)
+{
+	return get_fuse_inode(inode)->nodeid;
+}
+
+static inline int invalid_nodeid(u64 nodeid)
+{
+	return !nodeid || nodeid == FUSE_ROOT_ID;
+}
+
+static inline u64 fuse_get_attr_version(struct fuse_conn *fc)
+{
+	return atomic64_read(&fc->attr_version);
+}
+
+static inline void fuse_make_bad(struct inode *inode)
+{
+	set_bit(FUSE_I_BAD, &get_fuse_inode(inode)->state);
+}
+
+static inline bool fuse_is_bad(struct inode *inode)
+{
+	return unlikely(test_bit(FUSE_I_BAD, &get_fuse_inode(inode)->state));
+}
+
+extern const struct dentry_operations fuse_dentry_operations;
+extern const struct dentry_operations fuse_root_dentry_operations;
+
+/**
+ * Get a filled in inode
+ */
+struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
+			int generation, struct fuse_attr *attr,
+			u64 attr_valid, u64 attr_version);
+
+int fuse_lookup_name(struct super_block *sb, u64 nodeid, const struct qstr *name,
+		     struct fuse_entry_out *outarg, struct inode **inode);
+
+/**
+ * Send FORGET command
+ */
+void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget,
+		       u64 nodeid, u64 nlookup);
+
+struct fuse_forget_link *fuse_alloc_forget(void);
+
+struct fuse_forget_link *fuse_dequeue_forget(struct fuse_iqueue *fiq,
+					     unsigned int max,
+					     unsigned int *countp);
+
+/*
+ * Initialize READ or READDIR request
+ */
+struct fuse_io_args {
+	union {
+		struct {
+			struct fuse_read_in in;
+			u64 attr_ver;
+		} read;
+		struct {
+			struct fuse_write_in in;
+			struct fuse_write_out out;
+		} write;
+	};
+	struct fuse_args_pages ap;
+	struct fuse_io_priv *io;
+	struct fuse_file *ff;
+};
+
+void fuse_read_args_fill(struct fuse_io_args *ia, struct file *file, loff_t pos,
+			 size_t count, int opcode);
+
+
+/**
+ * Send OPEN or OPENDIR request
+ */
+int fuse_open_common(struct inode *inode, struct file *file, bool isdir);
+
+struct fuse_file *fuse_file_alloc(struct fuse_mount *fm);
+void fuse_file_free(struct fuse_file *ff);
+void fuse_finish_open(struct inode *inode, struct file *file);
+
+/**
+ * Send RELEASE or RELEASEDIR request
+ */
+void fuse_release_common(struct file *file, bool isdir);
+
+/**
+ * Send FSYNC or FSYNCDIR request
+ */
+int fuse_fsync_common(struct file *file, loff_t start, loff_t end,
+		      int datasync, int opcode);
+
+/**
+ * Notify poll wakeup
+ */
+int fuse_notify_poll_wakeup(struct fuse_conn *fc,
+			    struct fuse_notify_poll_wakeup_out *outarg);
+
+/**
+ * Initialize file operations on a regular file
+ */
+void fuse_init_file_inode(struct inode *inode);
+
+/**
+ * Initialize inode operations on regular files and special files
+ */
+void fuse_init_common(struct inode *inode);
+
+/**
+ * Initialize inode and file operations on a directory
+ */
+void fuse_init_dir(struct inode *inode);
+
+/**
+ * Initialize inode operations on a symlink
+ */
+void fuse_init_symlink(struct inode *inode);
+
+/**
+ * Change attributes of an inode
+ */
+void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
+			    u64 attr_valid, u64 attr_version);
+
+void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
+				   u64 attr_valid);
+
+/**
+ * Initialize the client device
+ */
+int fuse_dev_init(void);
+
+/**
+ * Cleanup the client device
+ */
+void fuse_dev_cleanup(void);
+
+int fuse_ctl_init(void);
+void __exit fuse_ctl_cleanup(void);
+
+/**
+ * Simple request sending that does request allocation and freeing
+ */
+ssize_t fuse_simple_request(struct fuse_mount *fm, struct fuse_args *args);
+
+/**
+ * End a finished request
+ */
+void fuse_request_end(struct fuse_req *req);
+
+void fuse_wait_aborted(struct fuse_conn *fc);
+
+/**
+ * Invalidate inode attributes
+ */
+void fuse_invalidate_attr(struct inode *inode);
+
+void fuse_invalidate_entry_cache(struct dentry *entry);
+
+void fuse_invalidate_atime(struct inode *inode);
+
+u64 entry_attr_timeout(struct fuse_entry_out *o);
+void fuse_change_entry_timeout(struct dentry *entry, struct fuse_entry_out *o);
+
+struct fuse_dev *fuse_dev_alloc(void);
+void fuse_dev_install(struct fuse_dev *fud, struct fuse_conn *fc);
+void fuse_send_init(struct fuse_mount *fm);
+
+/**
+ * Fill in superblock and initialize fuse connection
+ * @sb: partially-initialized superblock to fill in
+ * @ctx: mount context
+ */
+int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx);
+
+/*
+ * Fill in superblock for submounts
+ * @sb: partially-initialized superblock to fill in
+ * @parent_fi: The fuse_inode of the parent filesystem where this submount is
+ * 	       mounted
+ */
+int fuse_fill_super_submount(struct super_block *sb,
+			     struct fuse_inode *parent_fi);
+
+/*
+ * Remove the mount from the connection
+ *
+ * Returns whether this was the last mount
+ */
+bool fuse_mount_remove(struct fuse_mount *fm);
+
+/*
+ * Shut down the connection (possibly sending DESTROY request).
+ */
+void fuse_conn_destroy(struct fuse_mount *fm);
+
+/**
+ * Add connection to control filesystem
+ */
+int fuse_ctl_add_conn(struct fuse_conn *fc);
+
+/**
+ * Remove connection from control filesystem
+ */
+void fuse_ctl_remove_conn(struct fuse_conn *fc);
+
+/**
+ * Is file type valid?
+ */
+int fuse_valid_type(int m);
+
+bool fuse_invalid_attr(struct fuse_attr *attr);
+
+/**
+ * Is current process allowed to perform filesystem operation?
+ */
+int fuse_allow_current_process(struct fuse_conn *fc);
+
+u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id);
+
+void fuse_update_ctime(struct inode *inode);
+
+int fuse_update_attributes(struct inode *inode, struct file *file);
+
+void fuse_flush_writepages(struct inode *inode);
+
+void fuse_set_nowrite(struct inode *inode);
+void fuse_release_nowrite(struct inode *inode);
+
+/**
+ * Scan all fuse_mounts belonging to fc to find the first where
+ * ilookup5() returns a result.  Return that result and the
+ * respective fuse_mount in *fm (unless fm is NULL).
+ *
+ * The caller must hold fc->killsb.
+ */
+struct inode *fuse_ilookup(struct fuse_conn *fc, u64 nodeid,
+			   struct fuse_mount **fm);
+
+/**
+ * File-system tells the kernel to invalidate cache for the given node id.
+ */
+int fuse_reverse_inval_inode(struct fuse_conn *fc, u64 nodeid,
+			     loff_t offset, loff_t len);
+
+/**
+ * File-system tells the kernel to invalidate parent attributes and
+ * the dentry matching parent/name.
+ *
+ * If the child_nodeid is non-zero and:
+ *    - matches the inode number for the dentry matching parent/name,
+ *    - is not a mount point
+ *    - is a file or oan empty directory
+ * then the dentry is unhashed (d_delete()).
+ */
+int fuse_reverse_inval_entry(struct fuse_conn *fc, u64 parent_nodeid,
+			     u64 child_nodeid, struct qstr *name);
+
+long fuse_ioctl_common(struct file *file, unsigned int cmd,
+		       unsigned long arg, unsigned int flags);
+
+bool fuse_write_update_size(struct inode *inode, loff_t pos);
+
+int fuse_flush_times(struct inode *inode, struct fuse_file *ff);
+int fuse_write_inode(struct inode *inode, struct writeback_control *wbc);
+
+int fuse_do_setattr(struct dentry *dentry, struct iattr *attr,
+		    struct file *file);
+
+void fuse_set_initialized(struct fuse_conn *fc);
+
+void fuse_unlock_inode(struct inode *inode, bool locked);
+bool fuse_lock_inode(struct inode *inode);
+
+int fuse_setxattr(struct inode *inode, const char *name, const void *value,
+		  size_t size, int flags);
+ssize_t fuse_getxattr(struct inode *inode, const char *name, void *value,
+		      size_t size);
+ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size);
+int fuse_removexattr(struct inode *inode, const char *name);
+extern const struct xattr_handler *fuse_xattr_handlers[];
+extern const struct xattr_handler *fuse_acl_xattr_handlers[];
+extern const struct xattr_handler *fuse_no_acl_xattr_handlers[];
+
+struct posix_acl;
+struct posix_acl *fuse_get_acl(struct inode *inode, int type);
+int fuse_set_acl(struct inode *inode, struct posix_acl *acl, int type);
+
+
+/* readdir.c */
+int fuse_readdir(struct file *file, struct dir_context *ctx);
+
+/**
+ * Return the number of bytes in an arguments list
+ */
+unsigned int fuse_len_args(unsigned int numargs, struct fuse_arg *args);
+
+/**
+ * Get the next unique ID for a request
+ */
+u64 fuse_get_unique(struct fuse_iqueue *fiq);
+void fuse_free_conn(struct fuse_conn *fc);
+
+/* dax.c */
+
+#define FUSE_IS_DAX(inode) (IS_ENABLED(CONFIG_FUSE_DAX) && IS_DAX(inode))
+
+ssize_t fuse_dax_read_iter(struct kiocb *iocb, struct iov_iter *to);
+ssize_t fuse_dax_write_iter(struct kiocb *iocb, struct iov_iter *from);
+int fuse_dax_mmap(struct file *file, struct vm_area_struct *vma);
+int fuse_dax_break_layouts(struct inode *inode, u64 dmap_start, u64 dmap_end);
+int fuse_dax_conn_alloc(struct fuse_conn *fc, struct dax_device *dax_dev);
+void fuse_dax_conn_free(struct fuse_conn *fc);
+bool fuse_dax_inode_alloc(struct super_block *sb, struct fuse_inode *fi);
+void fuse_dax_inode_init(struct inode *inode);
+void fuse_dax_inode_cleanup(struct inode *inode);
+bool fuse_dax_check_alignment(struct fuse_conn *fc, unsigned int map_alignment);
+void fuse_dax_cancel_work(struct fuse_conn *fc);
+
+#endif /* _FS_FUSE_I_H */
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 8efee00a2a1a..b0e18b470e91 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -6,6 +6,8 @@
   See the file COPYING.
 */
 
+#include "fuse_i.h"
+
 #include <linux/pagemap.h>
 #include <linux/slab.h>
 #include <linux/file.h>
@@ -22,8 +24,6 @@
 #include <linux/posix_acl.h>
 #include <linux/pid_namespace.h>
 
-#include <net/fuse.h>
-
 MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
 MODULE_DESCRIPTION("Filesystem in Userspace");
 MODULE_LICENSE("GPL");
diff --git a/fs/fuse/readdir.c b/fs/fuse/readdir.c
index a6e8660e40ef..3441ffa740f3 100644
--- a/fs/fuse/readdir.c
+++ b/fs/fuse/readdir.c
@@ -7,13 +7,12 @@
 */
 
 
+#include "fuse_i.h"
 #include <linux/iversion.h>
 #include <linux/posix_acl.h>
 #include <linux/pagemap.h>
 #include <linux/highmem.h>
 
-#include <net/fuse.h>
-
 static bool fuse_use_readdirplus(struct inode *dir, struct dir_context *ctx)
 {
 	struct fuse_conn *fc = get_fuse_conn(dir);
diff --git a/fs/fuse/virtio_fs.c b/fs/fuse/virtio_fs.c
index 57cc3fe3e07b..8868ac31a3c0 100644
--- a/fs/fuse/virtio_fs.c
+++ b/fs/fuse/virtio_fs.c
@@ -16,8 +16,7 @@
 #include <linux/fs_parser.h>
 #include <linux/highmem.h>
 #include <linux/uio.h>
-
-#include <net/fuse.h>
+#include "fuse_i.h"
 
 /* List of virtio-fs device instances and a lock for the list. Also provides
  * mutual exclusion in device removal and mounting path
diff --git a/fs/fuse/xattr.c b/fs/fuse/xattr.c
index 46a2919e53ca..cdea18de94f7 100644
--- a/fs/fuse/xattr.c
+++ b/fs/fuse/xattr.c
@@ -6,11 +6,11 @@
  * See the file COPYING.
  */
 
+#include "fuse_i.h"
+
 #include <linux/xattr.h>
 #include <linux/posix_acl_xattr.h>
 
-#include <net/fuse.h>
-
 int fuse_setxattr(struct inode *inode, const char *name, const void *value,
 		  size_t size, int flags)
 {
diff --git a/include/net/fuse.h b/include/net/fuse.h
index 7c4b8cb93f9f..2d6d63e7ad65 100644
--- a/include/net/fuse.h
+++ b/include/net/fuse.h
@@ -6,179 +6,27 @@
   See the file COPYING.
 */
 
-#ifndef _FS_FUSE_I_H
-#define _FS_FUSE_I_H
-
-#ifndef pr_fmt
-# define pr_fmt(fmt) "fuse: " fmt
-#endif
+#ifndef _NET_FUSE_H
+#define _NET_FUSE_H
 
 #include <linux/fuse.h>
-#include <linux/fs.h>
-#include <linux/mount.h>
-#include <linux/wait.h>
-#include <linux/list.h>
-#include <linux/spinlock.h>
-#include <linux/mm.h>
-#include <linux/backing-dev.h>
-#include <linux/mutex.h>
-#include <linux/rwsem.h>
-#include <linux/rbtree.h>
 #include <linux/poll.h>
-#include <linux/workqueue.h>
 #include <linux/kref.h>
-#include <linux/xattr.h>
-#include <linux/pid_namespace.h>
-#include <linux/refcount.h>
-#include <linux/user_namespace.h>
-
-/** Default max number of pages that can be used in a single read request */
-#define FUSE_DEFAULT_MAX_PAGES_PER_REQ 32
-
-/** Maximum of max_pages received in init_out */
-#define FUSE_MAX_MAX_PAGES 256
-
-/** Bias for fi->writectr, meaning new writepages must not be sent */
-#define FUSE_NOWRITE INT_MIN
-
-/** It could be as large as PATH_MAX, but would that have any uses? */
-#define FUSE_NAME_MAX 1024
 
 /** Number of dentries for each connection in the control filesystem */
 #define FUSE_CTL_NUM_DENTRIES 5
 
-/** List of active connections */
-extern struct list_head fuse_conn_list;
-
-/** Global mutex protecting fuse_conn_list and the control filesystem */
-extern struct mutex fuse_mutex;
-
-/** Module parameters */
-extern unsigned max_user_bgreq;
-extern unsigned max_user_congthresh;
-
 /* One forget request */
 struct fuse_forget_link {
 	struct fuse_forget_one forget_one;
 	struct fuse_forget_link *next;
 };
 
-/** FUSE inode */
-struct fuse_inode {
-	/** Inode data */
-	struct inode inode;
-
-	/** Unique ID, which identifies the inode between userspace
-	 * and kernel */
-	u64 nodeid;
-
-	/** Number of lookups on this inode */
-	u64 nlookup;
-
-	/** The request used for sending the FORGET message */
-	struct fuse_forget_link *forget;
-
-	/** Time in jiffies until the file attributes are valid */
-	u64 i_time;
-
-	/* Which attributes are invalid */
-	u32 inval_mask;
-
-	/** The sticky bit in inode->i_mode may have been removed, so
-	    preserve the original mode */
-	umode_t orig_i_mode;
-
-	/** 64 bit inode number */
-	u64 orig_ino;
-
-	/** Version of last attribute change */
-	u64 attr_version;
-
-	union {
-		/* Write related fields (regular file only) */
-		struct {
-			/* Files usable in writepage.  Protected by fi->lock */
-			struct list_head write_files;
-
-			/* Writepages pending on truncate or fsync */
-			struct list_head queued_writes;
-
-			/* Number of sent writes, a negative bias
-			 * (FUSE_NOWRITE) means more writes are blocked */
-			int writectr;
-
-			/* Waitq for writepage completion */
-			wait_queue_head_t page_waitq;
-
-			/* List of writepage requestst (pending or sent) */
-			struct rb_root writepages;
-		};
-
-		/* readdir cache (directory only) */
-		struct {
-			/* true if fully cached */
-			bool cached;
-
-			/* size of cache */
-			loff_t size;
-
-			/* position at end of cache (position of next entry) */
-			loff_t pos;
-
-			/* version of the cache */
-			u64 version;
-
-			/* modification time of directory when cache was
-			 * started */
-			struct timespec64 mtime;
-
-			/* iversion of directory when cache was started */
-			u64 iversion;
-
-			/* protects above fields */
-			spinlock_t lock;
-		} rdc;
-	};
-
-	/** Miscellaneous bits describing inode state */
-	unsigned long state;
-
-	/** Lock for serializing lookup and readdir for back compatibility*/
-	struct mutex mutex;
-
-	/** Lock to protect write related fields */
-	spinlock_t lock;
-
-	/**
-	 * Can't take inode lock in fault path (leads to circular dependency).
-	 * Introduce another semaphore which can be taken in fault path and
-	 * then other filesystem paths can take this to block faults.
-	 */
-	struct rw_semaphore i_mmap_sem;
-
-#ifdef CONFIG_FUSE_DAX
-	/*
-	 * Dax specific inode data
-	 */
-	struct fuse_inode_dax *dax;
-#endif
-};
-
-/** FUSE inode state bits */
-enum {
-	/** Advise readdirplus  */
-	FUSE_I_ADVISE_RDPLUS,
-	/** Initialized with readdirplus */
-	FUSE_I_INIT_RDPLUS,
-	/** An operation changing file size is in progress  */
-	FUSE_I_SIZE_UNSTABLE,
-	/* Bad inode */
-	FUSE_I_BAD,
-};
-
 struct fuse_conn;
 struct fuse_mount;
 struct fuse_release_args;
+struct fuse_inode;
+struct fuse_iqueue_ops;
 
 /** FUSE specific file data */
 struct fuse_file {
@@ -305,118 +153,6 @@ struct fuse_io_priv {
 	.iocb = i,			\
 }
 
-/**
- * Request flags
- *
- * FR_ISREPLY:		set if the request has reply
- * FR_FORCE:		force sending of the request even if interrupted
- * FR_BACKGROUND:	request is sent in the background
- * FR_WAITING:		request is counted as "waiting"
- * FR_ABORTED:		the request was aborted
- * FR_INTERRUPTED:	the request has been interrupted
- * FR_LOCKED:		data is being copied to/from the request
- * FR_PENDING:		request is not yet in userspace
- * FR_SENT:		request is in userspace, waiting for an answer
- * FR_FINISHED:		request is finished
- * FR_PRIVATE:		request is on private list
- * FR_ASYNC:		request is asynchronous
- */
-enum fuse_req_flag {
-	FR_ISREPLY,
-	FR_FORCE,
-	FR_BACKGROUND,
-	FR_WAITING,
-	FR_ABORTED,
-	FR_INTERRUPTED,
-	FR_LOCKED,
-	FR_PENDING,
-	FR_SENT,
-	FR_FINISHED,
-	FR_PRIVATE,
-	FR_ASYNC,
-};
-
-/**
- * A request to the client
- *
- * .waitq.lock protects the following fields:
- *   - FR_ABORTED
- *   - FR_LOCKED (may also be modified under fc->lock, tested under both)
- */
-struct fuse_req {
-	/** This can be on either pending processing or io lists in
-	    fuse_conn */
-	struct list_head list;
-
-	/** Entry on the interrupts list  */
-	struct list_head intr_entry;
-
-	/* Input/output arguments */
-	struct fuse_args *args;
-
-	/** refcount */
-	refcount_t count;
-
-	/* Request flags, updated with test/set/clear_bit() */
-	unsigned long flags;
-
-	/* The request input header */
-	struct {
-		struct fuse_in_header h;
-	} in;
-
-	/* The request output header */
-	struct {
-		struct fuse_out_header h;
-	} out;
-
-	/** Used to wake up the task waiting for completion of request*/
-	wait_queue_head_t waitq;
-
-#if IS_ENABLED(CONFIG_VIRTIO_FS)
-	/** virtio-fs's physically contiguous buffer for in and out args */
-	void *argbuf;
-#endif
-
-	/** fuse_mount this request belongs to */
-	struct fuse_mount *fm;
-};
-
-struct fuse_iqueue;
-
-/**
- * Input queue callbacks
- *
- * Input queue signalling is device-specific.  For example, the /dev/fuse file
- * uses fiq->waitq and fasync to wake processes that are waiting on queue
- * readiness.  These callbacks allow other device types to respond to input
- * queue activity.
- */
-struct fuse_iqueue_ops {
-	/**
-	 * Signal that a forget has been queued
-	 */
-	void (*wake_forget_and_unlock)(struct fuse_iqueue *fiq)
-		__releases(fiq->lock);
-
-	/**
-	 * Signal that an INTERRUPT request has been queued
-	 */
-	void (*wake_interrupt_and_unlock)(struct fuse_iqueue *fiq)
-		__releases(fiq->lock);
-
-	/**
-	 * Signal that a request has been queued
-	 */
-	void (*wake_pending_and_unlock)(struct fuse_iqueue *fiq)
-		__releases(fiq->lock);
-
-	/**
-	 * Clean up when fuse_iqueue is destroyed
-	 */
-	void (*release)(struct fuse_iqueue *fiq);
-};
-
 /** /dev/fuse input queue operations */
 extern const struct fuse_iqueue_ops fuse_dev_fiq_ops;
 
@@ -456,9 +192,6 @@ struct fuse_iqueue {
 	void *priv;
 };
 
-#define FUSE_PQ_HASH_BITS 8
-#define FUSE_PQ_HASH_SIZE (1 << FUSE_PQ_HASH_BITS)
-
 struct fuse_pqueue {
 	/** Connection established */
 	unsigned connected;
@@ -487,34 +220,6 @@ struct fuse_dev {
 	struct list_head entry;
 };
 
-struct fuse_fs_context {
-	int fd;
-	unsigned int rootmode;
-	kuid_t user_id;
-	kgid_t group_id;
-	bool is_bdev:1;
-	bool fd_present:1;
-	bool rootmode_present:1;
-	bool user_id_present:1;
-	bool group_id_present:1;
-	bool default_permissions:1;
-	bool allow_other:1;
-	bool destroy:1;
-	bool no_control:1;
-	bool no_force_umount:1;
-	bool legacy_opts_show:1;
-	bool dax:1;
-	unsigned int max_read;
-	unsigned int blksize;
-	const char *subtype;
-
-	/* DAX device, may be NULL */
-	struct dax_device *dax_dev;
-
-	/* fuse_dev pointer to fill in, should contain NULL on entry */
-	void **fudptr;
-};
-
 /**
  * A Fuse connection.
  *
@@ -821,204 +526,16 @@ struct fuse_mount {
 	struct list_head fc_entry;
 };
 
-static inline struct fuse_mount *get_fuse_mount_super(struct super_block *sb)
-{
-	return sb->s_fs_info;
-}
-
-static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb)
-{
-	return get_fuse_mount_super(sb)->fc;
-}
-
-static inline struct fuse_mount *get_fuse_mount(struct inode *inode)
-{
-	return get_fuse_mount_super(inode->i_sb);
-}
-
-static inline struct fuse_conn *get_fuse_conn(struct inode *inode)
-{
-	return get_fuse_mount_super(inode->i_sb)->fc;
-}
-
-static inline struct fuse_inode *get_fuse_inode(struct inode *inode)
-{
-	return container_of(inode, struct fuse_inode, inode);
-}
-
-static inline u64 get_node_id(struct inode *inode)
-{
-	return get_fuse_inode(inode)->nodeid;
-}
-
-static inline int invalid_nodeid(u64 nodeid)
-{
-	return !nodeid || nodeid == FUSE_ROOT_ID;
-}
-
-static inline u64 fuse_get_attr_version(struct fuse_conn *fc)
-{
-	return atomic64_read(&fc->attr_version);
-}
-
-static inline void fuse_make_bad(struct inode *inode)
-{
-	set_bit(FUSE_I_BAD, &get_fuse_inode(inode)->state);
-}
-
-static inline bool fuse_is_bad(struct inode *inode)
-{
-	return unlikely(test_bit(FUSE_I_BAD, &get_fuse_inode(inode)->state));
-}
-
 /** Device operations */
 extern const struct file_operations fuse_dev_operations;
 
-extern const struct dentry_operations fuse_dentry_operations;
-extern const struct dentry_operations fuse_root_dentry_operations;
-
-/**
- * Get a filled in inode
- */
-struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
-			int generation, struct fuse_attr *attr,
-			u64 attr_valid, u64 attr_version);
-
-int fuse_lookup_name(struct super_block *sb, u64 nodeid, const struct qstr *name,
-		     struct fuse_entry_out *outarg, struct inode **inode);
-
-/**
- * Send FORGET command
- */
-void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget,
-		       u64 nodeid, u64 nlookup);
-
-struct fuse_forget_link *fuse_alloc_forget(void);
-
-struct fuse_forget_link *fuse_dequeue_forget(struct fuse_iqueue *fiq,
-					     unsigned int max,
-					     unsigned int *countp);
-
-/*
- * Initialize READ or READDIR request
- */
-struct fuse_io_args {
-	union {
-		struct {
-			struct fuse_read_in in;
-			u64 attr_ver;
-		} read;
-		struct {
-			struct fuse_write_in in;
-			struct fuse_write_out out;
-		} write;
-	};
-	struct fuse_args_pages ap;
-	struct fuse_io_priv *io;
-	struct fuse_file *ff;
-};
-
-void fuse_read_args_fill(struct fuse_io_args *ia, struct file *file, loff_t pos,
-			 size_t count, int opcode);
-
-
-/**
- * Send OPEN or OPENDIR request
- */
-int fuse_open_common(struct inode *inode, struct file *file, bool isdir);
-
-struct fuse_file *fuse_file_alloc(struct fuse_mount *fm);
-void fuse_file_free(struct fuse_file *ff);
-void fuse_finish_open(struct inode *inode, struct file *file);
-
 void fuse_sync_release(struct fuse_inode *fi, struct fuse_file *ff, int flags);
 
-/**
- * Send RELEASE or RELEASEDIR request
- */
-void fuse_release_common(struct file *file, bool isdir);
-
-/**
- * Send FSYNC or FSYNCDIR request
- */
-int fuse_fsync_common(struct file *file, loff_t start, loff_t end,
-		      int datasync, int opcode);
-
-/**
- * Notify poll wakeup
- */
-int fuse_notify_poll_wakeup(struct fuse_conn *fc,
-			    struct fuse_notify_poll_wakeup_out *outarg);
-
-/**
- * Initialize file operations on a regular file
- */
-void fuse_init_file_inode(struct inode *inode);
-
-/**
- * Initialize inode operations on regular files and special files
- */
-void fuse_init_common(struct inode *inode);
-
-/**
- * Initialize inode and file operations on a directory
- */
-void fuse_init_dir(struct inode *inode);
-
-/**
- * Initialize inode operations on a symlink
- */
-void fuse_init_symlink(struct inode *inode);
-
-/**
- * Change attributes of an inode
- */
-void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
-			    u64 attr_valid, u64 attr_version);
-
-void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
-				   u64 attr_valid);
-
-/**
- * Initialize the client device
- */
-int fuse_dev_init(void);
-
-/**
- * Cleanup the client device
- */
-void fuse_dev_cleanup(void);
-
-int fuse_ctl_init(void);
-void __exit fuse_ctl_cleanup(void);
-
-/**
- * Simple request sending that does request allocation and freeing
- */
-ssize_t fuse_simple_request(struct fuse_mount *fm, struct fuse_args *args);
 int fuse_simple_background(struct fuse_mount *fm, struct fuse_args *args,
 			   gfp_t gfp_flags);
 
-/**
- * End a finished request
- */
-void fuse_request_end(struct fuse_req *req);
-
 /* Abort all requests */
 void fuse_abort_conn(struct fuse_conn *fc);
-void fuse_wait_aborted(struct fuse_conn *fc);
-
-/**
- * Invalidate inode attributes
- */
-void fuse_invalidate_attr(struct inode *inode);
-
-void fuse_invalidate_entry_cache(struct dentry *entry);
-
-void fuse_invalidate_atime(struct inode *inode);
-
-u64 entry_attr_timeout(struct fuse_entry_out *o);
-void fuse_change_entry_timeout(struct dentry *entry, struct fuse_entry_out *o);
 
 /**
  * Acquire reference to fuse_conn
@@ -1038,100 +555,7 @@ void fuse_conn_init(struct fuse_conn *fc, struct fuse_mount *fm,
 void fuse_conn_put(struct fuse_conn *fc);
 
 struct fuse_dev *fuse_dev_alloc_install(struct fuse_conn *fc);
-struct fuse_dev *fuse_dev_alloc(void);
-void fuse_dev_install(struct fuse_dev *fud, struct fuse_conn *fc);
 void fuse_dev_free(struct fuse_dev *fud);
-void fuse_send_init(struct fuse_mount *fm);
-
-/**
- * Fill in superblock and initialize fuse connection
- * @sb: partially-initialized superblock to fill in
- * @ctx: mount context
- */
-int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx);
-
-/*
- * Fill in superblock for submounts
- * @sb: partially-initialized superblock to fill in
- * @parent_fi: The fuse_inode of the parent filesystem where this submount is
- * 	       mounted
- */
-int fuse_fill_super_submount(struct super_block *sb,
-			     struct fuse_inode *parent_fi);
-
-/*
- * Remove the mount from the connection
- *
- * Returns whether this was the last mount
- */
-bool fuse_mount_remove(struct fuse_mount *fm);
-
-/*
- * Shut down the connection (possibly sending DESTROY request).
- */
-void fuse_conn_destroy(struct fuse_mount *fm);
-
-/**
- * Add connection to control filesystem
- */
-int fuse_ctl_add_conn(struct fuse_conn *fc);
-
-/**
- * Remove connection from control filesystem
- */
-void fuse_ctl_remove_conn(struct fuse_conn *fc);
-
-/**
- * Is file type valid?
- */
-int fuse_valid_type(int m);
-
-bool fuse_invalid_attr(struct fuse_attr *attr);
-
-/**
- * Is current process allowed to perform filesystem operation?
- */
-int fuse_allow_current_process(struct fuse_conn *fc);
-
-u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id);
-
-void fuse_update_ctime(struct inode *inode);
-
-int fuse_update_attributes(struct inode *inode, struct file *file);
-
-void fuse_flush_writepages(struct inode *inode);
-
-void fuse_set_nowrite(struct inode *inode);
-void fuse_release_nowrite(struct inode *inode);
-
-/**
- * Scan all fuse_mounts belonging to fc to find the first where
- * ilookup5() returns a result.  Return that result and the
- * respective fuse_mount in *fm (unless fm is NULL).
- *
- * The caller must hold fc->killsb.
- */
-struct inode *fuse_ilookup(struct fuse_conn *fc, u64 nodeid,
-			   struct fuse_mount **fm);
-
-/**
- * File-system tells the kernel to invalidate cache for the given node id.
- */
-int fuse_reverse_inval_inode(struct fuse_conn *fc, u64 nodeid,
-			     loff_t offset, loff_t len);
-
-/**
- * File-system tells the kernel to invalidate parent attributes and
- * the dentry matching parent/name.
- *
- * If the child_nodeid is non-zero and:
- *    - matches the inode number for the dentry matching parent/name,
- *    - is not a mount point
- *    - is a file or oan empty directory
- * then the dentry is unhashed (d_delete()).
- */
-int fuse_reverse_inval_entry(struct fuse_conn *fc, u64 parent_nodeid,
-			     u64 child_nodeid, struct qstr *name);
 
 int fuse_do_open(struct fuse_mount *fm, u64 nodeid, struct file *file,
 		 bool isdir);
@@ -1150,67 +574,7 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
 		       loff_t *ppos, int flags);
 long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
 		   unsigned int flags);
-long fuse_ioctl_common(struct file *file, unsigned int cmd,
-		       unsigned long arg, unsigned int flags);
 __poll_t fuse_file_poll(struct file *file, poll_table *wait);
 int fuse_dev_release(struct inode *inode, struct file *file);
 
-bool fuse_write_update_size(struct inode *inode, loff_t pos);
-
-int fuse_flush_times(struct inode *inode, struct fuse_file *ff);
-int fuse_write_inode(struct inode *inode, struct writeback_control *wbc);
-
-int fuse_do_setattr(struct dentry *dentry, struct iattr *attr,
-		    struct file *file);
-
-void fuse_set_initialized(struct fuse_conn *fc);
-
-void fuse_unlock_inode(struct inode *inode, bool locked);
-bool fuse_lock_inode(struct inode *inode);
-
-int fuse_setxattr(struct inode *inode, const char *name, const void *value,
-		  size_t size, int flags);
-ssize_t fuse_getxattr(struct inode *inode, const char *name, void *value,
-		      size_t size);
-ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size);
-int fuse_removexattr(struct inode *inode, const char *name);
-extern const struct xattr_handler *fuse_xattr_handlers[];
-extern const struct xattr_handler *fuse_acl_xattr_handlers[];
-extern const struct xattr_handler *fuse_no_acl_xattr_handlers[];
-
-struct posix_acl;
-struct posix_acl *fuse_get_acl(struct inode *inode, int type);
-int fuse_set_acl(struct inode *inode, struct posix_acl *acl, int type);
-
-
-/* readdir.c */
-int fuse_readdir(struct file *file, struct dir_context *ctx);
-
-/**
- * Return the number of bytes in an arguments list
- */
-unsigned int fuse_len_args(unsigned int numargs, struct fuse_arg *args);
-
-/**
- * Get the next unique ID for a request
- */
-u64 fuse_get_unique(struct fuse_iqueue *fiq);
-void fuse_free_conn(struct fuse_conn *fc);
-
-/* dax.c */
-
-#define FUSE_IS_DAX(inode) (IS_ENABLED(CONFIG_FUSE_DAX) && IS_DAX(inode))
-
-ssize_t fuse_dax_read_iter(struct kiocb *iocb, struct iov_iter *to);
-ssize_t fuse_dax_write_iter(struct kiocb *iocb, struct iov_iter *from);
-int fuse_dax_mmap(struct file *file, struct vm_area_struct *vma);
-int fuse_dax_break_layouts(struct inode *inode, u64 dmap_start, u64 dmap_end);
-int fuse_dax_conn_alloc(struct fuse_conn *fc, struct dax_device *dax_dev);
-void fuse_dax_conn_free(struct fuse_conn *fc);
-bool fuse_dax_inode_alloc(struct super_block *sb, struct fuse_inode *fi);
-void fuse_dax_inode_init(struct inode *inode);
-void fuse_dax_inode_cleanup(struct inode *inode);
-bool fuse_dax_check_alignment(struct fuse_conn *fc, unsigned int map_alignment);
-void fuse_dax_cancel_work(struct fuse_conn *fc);
-
-#endif /* _FS_FUSE_I_H */
+#endif /* _NET_FUSE_H */