7 files changed, 181 insertions, 234 deletions

diff --git a/fs/fuse/Kconfig b/fs/fuse/Kconfig
index ca215a3cba3e..a774166264de 100644
--- a/fs/fuse/Kconfig
+++ b/fs/fuse/Kconfig
@@ -2,6 +2,7 @@
 config FUSE_FS
 	tristate "FUSE (Filesystem in Userspace) support"
 	select FS_POSIX_ACL
+	select FS_IOMAP
 	help
 	  With FUSE it is possible to implement a fully functional filesystem
 	  in a userspace program.
diff --git a/fs/fuse/control.c b/fs/fuse/control.c
index 2a730d88cc3b..bb407705603c 100644
--- a/fs/fuse/control.c
+++ b/fs/fuse/control.c
@@ -11,6 +11,7 @@
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/fs_context.h>
+#include <linux/namei.h>
 
 #define FUSE_CTL_SUPER_MAGIC 0x65735543
 
@@ -212,7 +213,6 @@ static struct dentry *fuse_ctl_add_dentry(struct dentry *parent,
 	struct dentry *dentry;
 	struct inode *inode;
 
-	BUG_ON(fc->ctl_ndents >= FUSE_CTL_NUM_DENTRIES);
 	dentry = d_alloc_name(parent, name);
 	if (!dentry)
 		return NULL;
@@ -236,8 +236,6 @@ static struct dentry *fuse_ctl_add_dentry(struct dentry *parent,
 	inode->i_private = fc;
 	d_add(dentry, inode);
 
-	fc->ctl_dentry[fc->ctl_ndents++] = dentry;
-
 	return dentry;
 }
 
@@ -280,27 +278,29 @@ int fuse_ctl_add_conn(struct fuse_conn *fc)
 	return -ENOMEM;
 }
 
+static void remove_one(struct dentry *dentry)
+{
+	d_inode(dentry)->i_private = NULL;
+}
+
 /*
  * Remove a connection from the control filesystem (if it exists).
  * Caller must hold fuse_mutex
  */
 void fuse_ctl_remove_conn(struct fuse_conn *fc)
 {
-	int i;
+	struct dentry *dentry;
+	char name[32];
 
 	if (!fuse_control_sb || fc->no_control)
 		return;
 
-	for (i = fc->ctl_ndents - 1; i >= 0; i--) {
-		struct dentry *dentry = fc->ctl_dentry[i];
-		d_inode(dentry)->i_private = NULL;
-		if (!i) {
-			/* Get rid of submounts: */
-			d_invalidate(dentry);
-		}
-		dput(dentry);
+	sprintf(name, "%u", fc->dev);
+	dentry = lookup_noperm_positive_unlocked(&QSTR(name), fuse_control_sb->s_root);
+	if (!IS_ERR(dentry)) {
+		simple_recursive_removal(dentry, remove_one);
+		dput(dentry);	// paired with lookup_noperm_positive_unlocked()
 	}
-	drop_nlink(d_inode(fuse_control_sb->s_root));
 }
 
 static int fuse_ctl_fill_super(struct super_block *sb, struct fs_context *fsc)
@@ -346,12 +346,8 @@ static int fuse_ctl_init_fs_context(struct fs_context *fsc)
 
 static void fuse_ctl_kill_sb(struct super_block *sb)
 {
-	struct fuse_conn *fc;
-
 	mutex_lock(&fuse_mutex);
 	fuse_control_sb = NULL;
-	list_for_each_entry(fc, &fuse_conn_list, entry)
-		fc->ctl_ndents = 0;
 	mutex_unlock(&fuse_mutex);
 
 	kill_litter_super(sb);
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 45b4c3cc1396..2d817d7cab26 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -338,13 +338,6 @@ const struct dentry_operations fuse_dentry_operations = {
 	.d_automount	= fuse_dentry_automount,
 };
 
-const struct dentry_operations fuse_root_dentry_operations = {
-#if BITS_PER_LONG < 64
-	.d_init		= fuse_dentry_init,
-	.d_release	= fuse_dentry_release,
-#endif
-};
-
 int fuse_valid_type(int m)
 {
 	return S_ISREG(m) || S_ISDIR(m) || S_ISLNK(m) || S_ISCHR(m) ||
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index f102afc03359..95275a1e2f54 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -21,6 +21,7 @@
 #include <linux/filelock.h>
 #include <linux/splice.h>
 #include <linux/task_io_accounting_ops.h>
+#include <linux/iomap.h>
 
 static int fuse_send_open(struct fuse_mount *fm, u64 nodeid,
 			  unsigned int open_flags, int opcode,
@@ -788,12 +789,16 @@ static void fuse_short_read(struct inode *inode, u64 attr_ver, size_t num_read,
 	}
 }
 
-static int fuse_do_readfolio(struct file *file, struct folio *folio)
+static int fuse_do_readfolio(struct file *file, struct folio *folio,
+			     size_t off, size_t len)
 {
 	struct inode *inode = folio->mapping->host;
 	struct fuse_mount *fm = get_fuse_mount(inode);
-	loff_t pos = folio_pos(folio);
-	struct fuse_folio_desc desc = { .length = folio_size(folio) };
+	loff_t pos = folio_pos(folio) + off;
+	struct fuse_folio_desc desc = {
+		.offset = off,
+		.length = len,
+	};
 	struct fuse_io_args ia = {
 		.ap.args.page_zeroing = true,
 		.ap.args.out_pages = true,
@@ -820,8 +825,6 @@ static int fuse_do_readfolio(struct file *file, struct folio *folio)
 	if (res < desc.length)
 		fuse_short_read(inode, attr_ver, res, &ia.ap);
 
-	folio_mark_uptodate(folio);
-
 	return 0;
 }
 
@@ -834,13 +837,26 @@ static int fuse_read_folio(struct file *file, struct folio *folio)
 	if (fuse_is_bad(inode))
 		goto out;
 
-	err = fuse_do_readfolio(file, folio);
+	err = fuse_do_readfolio(file, folio, 0, folio_size(folio));
+	if (!err)
+		folio_mark_uptodate(folio);
+
 	fuse_invalidate_atime(inode);
  out:
 	folio_unlock(folio);
 	return err;
 }
 
+static int fuse_iomap_read_folio_range(const struct iomap_iter *iter,
+				       struct folio *folio, loff_t pos,
+				       size_t len)
+{
+	struct file *file = iter->private;
+	size_t off = offset_in_folio(folio, pos);
+
+	return fuse_do_readfolio(file, folio, off, len);
+}
+
 static void fuse_readpages_end(struct fuse_mount *fm, struct fuse_args *args,
 			       int err)
 {
@@ -1147,7 +1163,7 @@ static ssize_t fuse_send_write_pages(struct fuse_io_args *ia,
 static ssize_t fuse_fill_write_pages(struct fuse_io_args *ia,
 				     struct address_space *mapping,
 				     struct iov_iter *ii, loff_t pos,
-				     unsigned int max_pages)
+				     unsigned int max_folios)
 {
 	struct fuse_args_pages *ap = &ia->ap;
 	struct fuse_conn *fc = get_fuse_conn(mapping->host);
@@ -1157,12 +1173,11 @@ static ssize_t fuse_fill_write_pages(struct fuse_io_args *ia,
 	int err = 0;
 
 	num = min(iov_iter_count(ii), fc->max_write);
-	num = min(num, max_pages << PAGE_SHIFT);
 
 	ap->args.in_pages = true;
 	ap->descs[0].offset = offset;
 
-	while (num) {
+	while (num && ap->num_folios < max_folios) {
 		size_t tmp;
 		struct folio *folio;
 		pgoff_t index = pos >> PAGE_SHIFT;
@@ -1375,6 +1390,24 @@ static void fuse_dio_unlock(struct kiocb *iocb, bool exclusive)
 	}
 }
 
+static const struct iomap_write_ops fuse_iomap_write_ops = {
+	.read_folio_range = fuse_iomap_read_folio_range,
+};
+
+static int fuse_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
+			    unsigned int flags, struct iomap *iomap,
+			    struct iomap *srcmap)
+{
+	iomap->type = IOMAP_MAPPED;
+	iomap->length = length;
+	iomap->offset = offset;
+	return 0;
+}
+
+static const struct iomap_ops fuse_iomap_ops = {
+	.iomap_begin	= fuse_iomap_begin,
+};
+
 static ssize_t fuse_cache_write_iter(struct kiocb *iocb, struct iov_iter *from)
 {
 	struct file *file = iocb->ki_filp;
@@ -1384,6 +1417,7 @@ static ssize_t fuse_cache_write_iter(struct kiocb *iocb, struct iov_iter *from)
 	struct inode *inode = mapping->host;
 	ssize_t err, count;
 	struct fuse_conn *fc = get_fuse_conn(inode);
+	bool writeback = false;
 
 	if (fc->writeback_cache) {
 		/* Update size (EOF optimization) and mode (SUID clearing) */
@@ -1392,16 +1426,11 @@ static ssize_t fuse_cache_write_iter(struct kiocb *iocb, struct iov_iter *from)
 		if (err)
 			return err;
 
-		if (fc->handle_killpriv_v2 &&
-		    setattr_should_drop_suidgid(idmap,
-						file_inode(file))) {
-			goto writethrough;
-		}
-
-		return generic_file_write_iter(iocb, from);
+		if (!fc->handle_killpriv_v2 ||
+		    !setattr_should_drop_suidgid(idmap, file_inode(file)))
+			writeback = true;
 	}
 
-writethrough:
 	inode_lock(inode);
 
 	err = count = generic_write_checks(iocb, from);
@@ -1420,6 +1449,15 @@ writethrough:
 			goto out;
 		written = direct_write_fallback(iocb, from, written,
 				fuse_perform_write(iocb, from));
+	} else if (writeback) {
+		/*
+		 * Use iomap so that we can do granular uptodate reads
+		 * and granular dirty tracking for large folios.
+		 */
+		written = iomap_file_buffered_write(iocb, from,
+						    &fuse_iomap_ops,
+						    &fuse_iomap_write_ops,
+						    file);
 	} else {
 		written = fuse_perform_write(iocb, from);
 	}
@@ -1794,7 +1832,7 @@ static void fuse_writepage_finish(struct fuse_writepage_args *wpa)
 		 * scope of the fi->lock alleviates xarray lock
 		 * contention and noticeably improves performance.
 		 */
-		folio_end_writeback(ap->folios[i]);
+		iomap_finish_folio_write(inode, ap->folios[i], 1);
 		dec_wb_stat(&bdi->wb, WB_WRITEBACK);
 		wb_writeout_inc(&bdi->wb);
 	}
@@ -1981,19 +2019,20 @@ static void fuse_writepage_add_to_bucket(struct fuse_conn *fc,
 }
 
 static void fuse_writepage_args_page_fill(struct fuse_writepage_args *wpa, struct folio *folio,
-					  uint32_t folio_index)
+					  uint32_t folio_index, loff_t offset, unsigned len)
 {
 	struct inode *inode = folio->mapping->host;
 	struct fuse_args_pages *ap = &wpa->ia.ap;
 
 	ap->folios[folio_index] = folio;
-	ap->descs[folio_index].offset = 0;
-	ap->descs[folio_index].length = folio_size(folio);
+	ap->descs[folio_index].offset = offset;
+	ap->descs[folio_index].length = len;
 
 	inc_wb_stat(&inode_to_bdi(inode)->wb, WB_WRITEBACK);
 }
 
 static struct fuse_writepage_args *fuse_writepage_args_setup(struct folio *folio,
+							     size_t offset,
 							     struct fuse_file *ff)
 {
 	struct inode *inode = folio->mapping->host;
@@ -2006,7 +2045,7 @@ static struct fuse_writepage_args *fuse_writepage_args_setup(struct folio *folio
 		return NULL;
 
 	fuse_writepage_add_to_bucket(fc, wpa);
-	fuse_write_args_fill(&wpa->ia, ff, folio_pos(folio), 0);
+	fuse_write_args_fill(&wpa->ia, ff, folio_pos(folio) + offset, 0);
 	wpa->ia.write.in.write_flags |= FUSE_WRITE_CACHE;
 	wpa->inode = inode;
 	wpa->ia.ff = ff;
@@ -2018,63 +2057,28 @@ static struct fuse_writepage_args *fuse_writepage_args_setup(struct folio *folio
 	return wpa;
 }
 
-static int fuse_writepage_locked(struct folio *folio)
-{
-	struct address_space *mapping = folio->mapping;
-	struct inode *inode = mapping->host;
-	struct fuse_inode *fi = get_fuse_inode(inode);
-	struct fuse_writepage_args *wpa;
-	struct fuse_args_pages *ap;
-	struct fuse_file *ff;
-	int error = -EIO;
-
-	ff = fuse_write_file_get(fi);
-	if (!ff)
-		goto err;
-
-	wpa = fuse_writepage_args_setup(folio, ff);
-	error = -ENOMEM;
-	if (!wpa)
-		goto err_writepage_args;
-
-	ap = &wpa->ia.ap;
-	ap->num_folios = 1;
-
-	folio_start_writeback(folio);
-	fuse_writepage_args_page_fill(wpa, folio, 0);
-
-	spin_lock(&fi->lock);
-	list_add_tail(&wpa->queue_entry, &fi->queued_writes);
-	fuse_flush_writepages(inode);
-	spin_unlock(&fi->lock);
-
-	return 0;
-
-err_writepage_args:
-	fuse_file_put(ff, false);
-err:
-	mapping_set_error(folio->mapping, error);
-	return error;
-}
-
 struct fuse_fill_wb_data {
 	struct fuse_writepage_args *wpa;
 	struct fuse_file *ff;
-	struct inode *inode;
 	unsigned int max_folios;
-	unsigned int nr_pages;
+	/*
+	 * nr_bytes won't overflow since fuse_writepage_need_send() caps
+	 * wb requests to never exceed fc->max_pages (which has an upper bound
+	 * of U16_MAX).
+	 */
+	unsigned int nr_bytes;
 };
 
-static bool fuse_pages_realloc(struct fuse_fill_wb_data *data)
+static bool fuse_pages_realloc(struct fuse_fill_wb_data *data,
+			       unsigned int max_pages)
 {
 	struct fuse_args_pages *ap = &data->wpa->ia.ap;
-	struct fuse_conn *fc = get_fuse_conn(data->inode);
 	struct folio **folios;
 	struct fuse_folio_desc *descs;
 	unsigned int nfolios = min_t(unsigned int,
 				     max_t(unsigned int, data->max_folios * 2,
 					   FUSE_DEFAULT_MAX_PAGES_PER_REQ),
-				    fc->max_pages);
+				    max_pages);
 	WARN_ON(nfolios <= data->max_folios);
 
 	folios = fuse_folios_alloc(nfolios, GFP_NOFS, &descs);
@@ -2091,10 +2095,10 @@ static bool fuse_pages_realloc(struct fuse_fill_wb_data *data)
 	return true;
 }
 
-static void fuse_writepages_send(struct fuse_fill_wb_data *data)
+static void fuse_writepages_send(struct inode *inode,
+				 struct fuse_fill_wb_data *data)
 {
 	struct fuse_writepage_args *wpa = data->wpa;
-	struct inode *inode = data->inode;
 	struct fuse_inode *fi = get_fuse_inode(inode);
 
 	spin_lock(&fi->lock);
@@ -2103,195 +2107,148 @@ static void fuse_writepages_send(struct fuse_fill_wb_data *data)
 	spin_unlock(&fi->lock);
 }
 
-static bool fuse_writepage_need_send(struct fuse_conn *fc, struct folio *folio,
-				     struct fuse_args_pages *ap,
+static bool fuse_writepage_need_send(struct fuse_conn *fc, loff_t pos,
+				     unsigned len, struct fuse_args_pages *ap,
 				     struct fuse_fill_wb_data *data)
 {
+	struct folio *prev_folio;
+	struct fuse_folio_desc prev_desc;
+	unsigned bytes = data->nr_bytes + len;
+	loff_t prev_pos;
+
 	WARN_ON(!ap->num_folios);
 
 	/* Reached max pages */
-	if (data->nr_pages + folio_nr_pages(folio) > fc->max_pages)
+	if ((bytes + PAGE_SIZE - 1) >> PAGE_SHIFT > fc->max_pages)
 		return true;
 
 	/* Reached max write bytes */
-	if ((data->nr_pages * PAGE_SIZE) + folio_size(folio) > fc->max_write)
+	if (bytes > fc->max_write)
 		return true;
 
 	/* Discontinuity */
-	if (folio_next_index(ap->folios[ap->num_folios - 1]) != folio->index)
+	prev_folio = ap->folios[ap->num_folios - 1];
+	prev_desc = ap->descs[ap->num_folios - 1];
+	prev_pos = folio_pos(prev_folio) + prev_desc.offset + prev_desc.length;
+	if (prev_pos != pos)
 		return true;
 
 	/* Need to grow the pages array?  If so, did the expansion fail? */
-	if (ap->num_folios == data->max_folios && !fuse_pages_realloc(data))
+	if (ap->num_folios == data->max_folios &&
+	    !fuse_pages_realloc(data, fc->max_pages))
 		return true;
 
 	return false;
 }
 
-static int fuse_writepages_fill(struct folio *folio,
-		struct writeback_control *wbc, void *_data)
+static ssize_t fuse_iomap_writeback_range(struct iomap_writepage_ctx *wpc,
+					  struct folio *folio, u64 pos,
+					  unsigned len, u64 end_pos)
 {
-	struct fuse_fill_wb_data *data = _data;
+	struct fuse_fill_wb_data *data = wpc->wb_ctx;
 	struct fuse_writepage_args *wpa = data->wpa;
 	struct fuse_args_pages *ap = &wpa->ia.ap;
-	struct inode *inode = data->inode;
+	struct inode *inode = wpc->inode;
 	struct fuse_inode *fi = get_fuse_inode(inode);
 	struct fuse_conn *fc = get_fuse_conn(inode);
-	int err;
+	loff_t offset = offset_in_folio(folio, pos);
+
+	WARN_ON_ONCE(!data);
 
 	if (!data->ff) {
-		err = -EIO;
 		data->ff = fuse_write_file_get(fi);
 		if (!data->ff)
-			goto out_unlock;
+			return -EIO;
 	}
 
-	if (wpa && fuse_writepage_need_send(fc, folio, ap, data)) {
-		fuse_writepages_send(data);
+	if (wpa && fuse_writepage_need_send(fc, pos, len, ap, data)) {
+		fuse_writepages_send(inode, data);
 		data->wpa = NULL;
-		data->nr_pages = 0;
+		data->nr_bytes = 0;
 	}
 
 	if (data->wpa == NULL) {
-		err = -ENOMEM;
-		wpa = fuse_writepage_args_setup(folio, data->ff);
+		wpa = fuse_writepage_args_setup(folio, offset, data->ff);
 		if (!wpa)
-			goto out_unlock;
+			return -ENOMEM;
 		fuse_file_get(wpa->ia.ff);
 		data->max_folios = 1;
 		ap = &wpa->ia.ap;
 	}
-	folio_start_writeback(folio);
 
-	fuse_writepage_args_page_fill(wpa, folio, ap->num_folios);
-	data->nr_pages += folio_nr_pages(folio);
+	iomap_start_folio_write(inode, folio, 1);
+	fuse_writepage_args_page_fill(wpa, folio, ap->num_folios,
+				      offset, len);
+	data->nr_bytes += len;
 
-	err = 0;
 	ap->num_folios++;
 	if (!data->wpa)
 		data->wpa = wpa;
-out_unlock:
-	folio_unlock(folio);
 
-	return err;
+	return len;
 }
 
-static int fuse_writepages(struct address_space *mapping,
-			   struct writeback_control *wbc)
+static int fuse_iomap_writeback_submit(struct iomap_writepage_ctx *wpc,
+				       int error)
 {
-	struct inode *inode = mapping->host;
-	struct fuse_conn *fc = get_fuse_conn(inode);
-	struct fuse_fill_wb_data data;
-	int err;
+	struct fuse_fill_wb_data *data = wpc->wb_ctx;
 
-	err = -EIO;
-	if (fuse_is_bad(inode))
-		goto out;
-
-	if (wbc->sync_mode == WB_SYNC_NONE &&
-	    fc->num_background >= fc->congestion_threshold)
-		return 0;
+	WARN_ON_ONCE(!data);
 
-	data.inode = inode;
-	data.wpa = NULL;
-	data.ff = NULL;
-	data.nr_pages = 0;
-
-	err = write_cache_pages(mapping, wbc, fuse_writepages_fill, &data);
-	if (data.wpa) {
-		WARN_ON(!data.wpa->ia.ap.num_folios);
-		fuse_writepages_send(&data);
+	if (data->wpa) {
+		WARN_ON(!data->wpa->ia.ap.num_folios);
+		fuse_writepages_send(wpc->inode, data);
 	}
-	if (data.ff)
-		fuse_file_put(data.ff, false);
 
-out:
-	return err;
-}
-
-/*
- * It's worthy to make sure that space is reserved on disk for the write,
- * but how to implement it without killing performance need more thinking.
- */
-static int fuse_write_begin(struct file *file, struct address_space *mapping,
-		loff_t pos, unsigned len, struct folio **foliop, void **fsdata)
-{
-	pgoff_t index = pos >> PAGE_SHIFT;
-	struct fuse_conn *fc = get_fuse_conn(file_inode(file));
-	struct folio *folio;
-	loff_t fsize;
-	int err = -ENOMEM;
-
-	WARN_ON(!fc->writeback_cache);
-
-	folio = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN,
-			mapping_gfp_mask(mapping));
-	if (IS_ERR(folio))
-		goto error;
-
-	if (folio_test_uptodate(folio) || len >= folio_size(folio))
-		goto success;
-	/*
-	 * Check if the start of this folio comes after the end of file,
-	 * in which case the readpage can be optimized away.
-	 */
-	fsize = i_size_read(mapping->host);
-	if (fsize <= folio_pos(folio)) {
-		size_t off = offset_in_folio(folio, pos);
-		if (off)
-			folio_zero_segment(folio, 0, off);
-		goto success;
-	}
-	err = fuse_do_readfolio(file, folio);
-	if (err)
-		goto cleanup;
-success:
-	*foliop = folio;
-	return 0;
+	if (data->ff)
+		fuse_file_put(data->ff, false);
 
-cleanup:
-	folio_unlock(folio);
-	folio_put(folio);
-error:
-	return err;
+	return error;
 }
 
-static int fuse_write_end(struct file *file, struct address_space *mapping,
-		loff_t pos, unsigned len, unsigned copied,
-		struct folio *folio, void *fsdata)
-{
-	struct inode *inode = folio->mapping->host;
-
-	/* Haven't copied anything?  Skip zeroing, size extending, dirtying. */
-	if (!copied)
-		goto unlock;
-
-	pos += copied;
-	if (!folio_test_uptodate(folio)) {
-		/* Zero any unwritten bytes at the end of the page */
-		size_t endoff = pos & ~PAGE_MASK;
-		if (endoff)
-			folio_zero_segment(folio, endoff, PAGE_SIZE);
-		folio_mark_uptodate(folio);
-	}
+static const struct iomap_writeback_ops fuse_writeback_ops = {
+	.writeback_range	= fuse_iomap_writeback_range,
+	.writeback_submit	= fuse_iomap_writeback_submit,
+};
 
-	if (pos > inode->i_size)
-		i_size_write(inode, pos);
+static int fuse_writepages(struct address_space *mapping,
+			   struct writeback_control *wbc)
+{
+	struct inode *inode = mapping->host;
+	struct fuse_conn *fc = get_fuse_conn(inode);
+	struct fuse_fill_wb_data data = {};
+	struct iomap_writepage_ctx wpc = {
+		.inode = inode,
+		.iomap.type = IOMAP_MAPPED,
+		.wbc = wbc,
+		.ops = &fuse_writeback_ops,
+		.wb_ctx	= &data,
+	};
 
-	folio_mark_dirty(folio);
+	if (fuse_is_bad(inode))
+		return -EIO;
 
-unlock:
-	folio_unlock(folio);
-	folio_put(folio);
+	if (wbc->sync_mode == WB_SYNC_NONE &&
+	    fc->num_background >= fc->congestion_threshold)
+		return 0;
 
-	return copied;
+	return iomap_writepages(&wpc);
 }
 
 static int fuse_launder_folio(struct folio *folio)
 {
 	int err = 0;
+	struct fuse_fill_wb_data data = {};
+	struct iomap_writepage_ctx wpc = {
+		.inode = folio->mapping->host,
+		.iomap.type = IOMAP_MAPPED,
+		.ops = &fuse_writeback_ops,
+		.wb_ctx	= &data,
+	};
+
 	if (folio_clear_dirty_for_io(folio)) {
-		err = fuse_writepage_locked(folio);
+		err = iomap_writeback_folio(&wpc, folio);
+		err = fuse_iomap_writeback_submit(&wpc, err);
 		if (!err)
 			folio_wait_writeback(folio);
 	}
@@ -3144,12 +3101,13 @@ static const struct address_space_operations fuse_file_aops  = {
 	.readahead	= fuse_readahead,
 	.writepages	= fuse_writepages,
 	.launder_folio	= fuse_launder_folio,
-	.dirty_folio	= filemap_dirty_folio,
+	.dirty_folio	= iomap_dirty_folio,
+	.release_folio	= iomap_release_folio,
+	.invalidate_folio = iomap_invalidate_folio,
+	.is_partially_uptodate = iomap_is_partially_uptodate,
 	.migrate_folio	= filemap_migrate_folio,
 	.bmap		= fuse_bmap,
 	.direct_IO	= fuse_direct_IO,
-	.write_begin	= fuse_write_begin,
-	.write_end	= fuse_write_end,
 };
 
 void fuse_init_file_inode(struct inode *inode, unsigned int flags)
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index b54f4f57789f..ec248d13c8bf 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -913,12 +913,6 @@ struct fuse_conn {
 	/** Device ID from the root super block */
 	dev_t dev;
 
-	/** Dentries in the control filesystem */
-	struct dentry *ctl_dentry[FUSE_CTL_NUM_DENTRIES];
-
-	/** number of dentries used in the above array */
-	int ctl_ndents;
-
 	/** Key for lock owner ID scrambling */
 	u32 scramble_key[4];
 
@@ -1109,7 +1103,6 @@ static inline void fuse_sync_bucket_dec(struct fuse_sync_bucket *bucket)
 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
@@ -1486,9 +1479,9 @@ void fuse_dax_cancel_work(struct fuse_conn *fc);
 long fuse_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
 long fuse_file_compat_ioctl(struct file *file, unsigned int cmd,
 			    unsigned long arg);
-int fuse_fileattr_get(struct dentry *dentry, struct fileattr *fa);
+int fuse_fileattr_get(struct dentry *dentry, struct file_kattr *fa);
 int fuse_fileattr_set(struct mnt_idmap *idmap,
-		      struct dentry *dentry, struct fileattr *fa);
+		      struct dentry *dentry, struct file_kattr *fa);
 
 /* iomode.c */
 int fuse_file_cached_io_open(struct inode *inode, struct fuse_file *ff);
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index bfe8d8af46f3..ecb869e895ab 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -9,6 +9,7 @@
 #include "fuse_i.h"
 #include "dev_uring_i.h"
 
+#include <linux/dax.h>
 #include <linux/pagemap.h>
 #include <linux/slab.h>
 #include <linux/file.h>
@@ -162,6 +163,9 @@ static void fuse_evict_inode(struct inode *inode)
 	/* Will write inode on close/munmap and in all other dirtiers */
 	WARN_ON(inode->i_state & I_DIRTY_INODE);
 
+	if (FUSE_IS_DAX(inode))
+		dax_break_layout_final(inode);
+
 	truncate_inode_pages_final(&inode->i_data);
 	clear_inode(inode);
 	if (inode->i_sb->s_flags & SB_ACTIVE) {
@@ -1715,7 +1719,7 @@ static int fuse_fill_super_submount(struct super_block *sb,
 	fi = get_fuse_inode(root);
 	fi->nlookup--;
 
-	sb->s_d_op = &fuse_dentry_operations;
+	set_default_d_op(sb, &fuse_dentry_operations);
 	sb->s_root = d_make_root(root);
 	if (!sb->s_root)
 		return -ENOMEM;
@@ -1850,12 +1854,10 @@ int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx)
 
 	err = -ENOMEM;
 	root = fuse_get_root_inode(sb, ctx->rootmode);
-	sb->s_d_op = &fuse_root_dentry_operations;
+	set_default_d_op(sb, &fuse_dentry_operations);
 	root_dentry = d_make_root(root);
 	if (!root_dentry)
 		goto err_dev_free;
-	/* Root dentry doesn't have .d_revalidate */
-	sb->s_d_op = &fuse_dentry_operations;
 
 	mutex_lock(&fuse_mutex);
 	err = -EINVAL;
diff --git a/fs/fuse/ioctl.c b/fs/fuse/ioctl.c
index 2d9abf48828f..57032eadca6c 100644
--- a/fs/fuse/ioctl.c
+++ b/fs/fuse/ioctl.c
@@ -502,7 +502,7 @@ static void fuse_priv_ioctl_cleanup(struct inode *inode, struct fuse_file *ff)
 	fuse_file_release(inode, ff, O_RDONLY, NULL, S_ISDIR(inode->i_mode));
 }
 
-int fuse_fileattr_get(struct dentry *dentry, struct fileattr *fa)
+int fuse_fileattr_get(struct dentry *dentry, struct file_kattr *fa)
 {
 	struct inode *inode = d_inode(dentry);
 	struct fuse_file *ff;
@@ -536,11 +536,13 @@ int fuse_fileattr_get(struct dentry *dentry, struct fileattr *fa)
 cleanup:
 	fuse_priv_ioctl_cleanup(inode, ff);
 
+	if (err == -ENOTTY)
+		err = -EOPNOTSUPP;
 	return err;
 }
 
 int fuse_fileattr_set(struct mnt_idmap *idmap,
-		      struct dentry *dentry, struct fileattr *fa)
+		      struct dentry *dentry, struct file_kattr *fa)
 {
 	struct inode *inode = d_inode(dentry);
 	struct fuse_file *ff;
@@ -572,5 +574,7 @@ int fuse_fileattr_set(struct mnt_idmap *idmap,
 cleanup:
 	fuse_priv_ioctl_cleanup(inode, ff);
 
+	if (err == -ENOTTY)
+		err = -EOPNOTSUPP;
 	return err;
 }