Message-Id: <20260106131110.46687-8-linkinjeon@kernel.org>
Date: Tue,  6 Jan 2026 22:11:03 +0900
From: Namjae Jeon <linkinjeon@...nel.org>
To: viro@...iv.linux.org.uk,
	brauner@...nel.org,
	hch@...radead.org,
	hch@....de,
	tytso@....edu,
	willy@...radead.org,
	jack@...e.cz,
	djwong@...nel.org,
	josef@...icpanda.com,
	sandeen@...deen.net,
	rgoldwyn@...e.com,
	xiang@...nel.org,
	dsterba@...e.com,
	pali@...nel.org,
	ebiggers@...nel.org,
	neil@...wn.name,
	amir73il@...il.com
Cc: linux-fsdevel@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	iamjoonsoo.kim@....com,
	cheol.lee@....com,
	jay.sim@....com,
	gunho.lee@....com,
	Namjae Jeon <linkinjeon@...nel.org>,
	Hyunchul Lee <hyc.lee@...il.com>
Subject: [PATCH v4 07/14] ntfs: update iomap and address space operations

This updates the implementation of iomap and address space operations.

Signed-off-by: Hyunchul Lee <hyc.lee@...il.com>
Signed-off-by: Namjae Jeon <linkinjeon@...nel.org>
---
 fs/ntfs/aops.c  | 1871 +++++++++--------------------------------------
 fs/ntfs/iomap.c |  753 +++++++++++++++++++
 2 files changed, 1088 insertions(+), 1536 deletions(-)
 create mode 100644 fs/ntfs/iomap.c

diff --git a/fs/ntfs/aops.c b/fs/ntfs/aops.c
index 2d01517a2d59..e6670e5bb03e 100644
--- a/fs/ntfs/aops.c
+++ b/fs/ntfs/aops.c
@@ -1,354 +1,36 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * aops.c - NTFS kernel address space operations and page cache handling.
+/**
+ * NTFS kernel address space operations and page cache handling.
  *
  * Copyright (c) 2001-2014 Anton Altaparmakov and Tuxera Inc.
  * Copyright (c) 2002 Richard Russon
+ * Copyright (c) 2025 LG Electronics Co., Ltd.
  */
 
-#include <linux/errno.h>
-#include <linux/fs.h>
-#include <linux/gfp.h>
-#include <linux/mm.h>
-#include <linux/pagemap.h>
-#include <linux/swap.h>
-#include <linux/buffer_head.h>
 #include <linux/writeback.h>
-#include <linux/bit_spinlock.h>
-#include <linux/bio.h>
+#include <linux/mpage.h>
+#include <linux/uio.h>
 
 #include "aops.h"
 #include "attrib.h"
-#include "debug.h"
-#include "inode.h"
 #include "mft.h"
-#include "runlist.h"
-#include "types.h"
 #include "ntfs.h"
+#include "debug.h"
+#include "iomap.h"
 
-/**
- * ntfs_end_buffer_async_read - async io completion for reading attributes
- * @bh:		buffer head on which io is completed
- * @uptodate:	whether @bh is now uptodate or not
- *
- * Asynchronous I/O completion handler for reading pages belonging to the
- * attribute address space of an inode.  The inodes can either be files or
- * directories or they can be fake inodes describing some attribute.
- *
- * If NInoMstProtected(), perform the post read mst fixups when all IO on the
- * page has been completed and mark the page uptodate or set the error bit on
- * the page.  To determine the size of the records that need fixing up, we
- * cheat a little bit by setting the index_block_size in ntfs_inode to the ntfs
- * record size, and index_block_size_bits, to the log(base 2) of the ntfs
- * record size.
- */
-static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
+static s64 ntfs_convert_folio_index_into_lcn(struct ntfs_volume *vol, struct ntfs_inode *ni,
+		unsigned long folio_index)
 {
-	unsigned long flags;
-	struct buffer_head *first, *tmp;
-	struct page *page;
-	struct inode *vi;
-	ntfs_inode *ni;
-	int page_uptodate = 1;
-
-	page = bh->b_page;
-	vi = page->mapping->host;
-	ni = NTFS_I(vi);
-
-	if (likely(uptodate)) {
-		loff_t i_size;
-		s64 file_ofs, init_size;
-
-		set_buffer_uptodate(bh);
-
-		file_ofs = ((s64)page->index << PAGE_SHIFT) +
-				bh_offset(bh);
-		read_lock_irqsave(&ni->size_lock, flags);
-		init_size = ni->initialized_size;
-		i_size = i_size_read(vi);
-		read_unlock_irqrestore(&ni->size_lock, flags);
-		if (unlikely(init_size > i_size)) {
-			/* Race with shrinking truncate. */
-			init_size = i_size;
-		}
-		/* Check for the current buffer head overflowing. */
-		if (unlikely(file_ofs + bh->b_size > init_size)) {
-			int ofs;
-			void *kaddr;
-
-			ofs = 0;
-			if (file_ofs < init_size)
-				ofs = init_size - file_ofs;
-			kaddr = kmap_atomic(page);
-			memset(kaddr + bh_offset(bh) + ofs, 0,
-					bh->b_size - ofs);
-			flush_dcache_page(page);
-			kunmap_atomic(kaddr);
-		}
-	} else {
-		clear_buffer_uptodate(bh);
-		SetPageError(page);
-		ntfs_error(ni->vol->sb, "Buffer I/O error, logical block "
-				"0x%llx.", (unsigned long long)bh->b_blocknr);
-	}
-	first = page_buffers(page);
-	spin_lock_irqsave(&first->b_uptodate_lock, flags);
-	clear_buffer_async_read(bh);
-	unlock_buffer(bh);
-	tmp = bh;
-	do {
-		if (!buffer_uptodate(tmp))
-			page_uptodate = 0;
-		if (buffer_async_read(tmp)) {
-			if (likely(buffer_locked(tmp)))
-				goto still_busy;
-			/* Async buffers must be locked. */
-			BUG();
-		}
-		tmp = tmp->b_this_page;
-	} while (tmp != bh);
-	spin_unlock_irqrestore(&first->b_uptodate_lock, flags);
-	/*
-	 * If none of the buffers had errors then we can set the page uptodate,
-	 * but we first have to perform the post read mst fixups, if the
-	 * attribute is mst protected, i.e. if NInoMstProteced(ni) is true.
-	 * Note we ignore fixup errors as those are detected when
-	 * map_mft_record() is called which gives us per record granularity
-	 * rather than per page granularity.
-	 */
-	if (!NInoMstProtected(ni)) {
-		if (likely(page_uptodate && !PageError(page)))
-			SetPageUptodate(page);
-	} else {
-		u8 *kaddr;
-		unsigned int i, recs;
-		u32 rec_size;
-
-		rec_size = ni->itype.index.block_size;
-		recs = PAGE_SIZE / rec_size;
-		/* Should have been verified before we got here... */
-		BUG_ON(!recs);
-		kaddr = kmap_atomic(page);
-		for (i = 0; i < recs; i++)
-			post_read_mst_fixup((NTFS_RECORD*)(kaddr +
-					i * rec_size), rec_size);
-		kunmap_atomic(kaddr);
-		flush_dcache_page(page);
-		if (likely(page_uptodate && !PageError(page)))
-			SetPageUptodate(page);
-	}
-	unlock_page(page);
-	return;
-still_busy:
-	spin_unlock_irqrestore(&first->b_uptodate_lock, flags);
-	return;
-}
+	s64 vcn;
+	s64 lcn;
 
-/**
- * ntfs_read_block - fill a @folio of an address space with data
- * @folio:	page cache folio to fill with data
- *
- * We read each buffer asynchronously and when all buffers are read in, our io
- * completion handler ntfs_end_buffer_read_async(), if required, automatically
- * applies the mst fixups to the folio before finally marking it uptodate and
- * unlocking it.
- *
- * We only enforce allocated_size limit because i_size is checked for in
- * generic_file_read().
- *
- * Return 0 on success and -errno on error.
- *
- * Contains an adapted version of fs/buffer.c::block_read_full_folio().
- */
-static int ntfs_read_block(struct folio *folio)
-{
-	loff_t i_size;
-	VCN vcn;
-	LCN lcn;
-	s64 init_size;
-	struct inode *vi;
-	ntfs_inode *ni;
-	ntfs_volume *vol;
-	runlist_element *rl;
-	struct buffer_head *bh, *head, *arr[MAX_BUF_PER_PAGE];
-	sector_t iblock, lblock, zblock;
-	unsigned long flags;
-	unsigned int blocksize, vcn_ofs;
-	int i, nr;
-	unsigned char blocksize_bits;
-
-	vi = folio->mapping->host;
-	ni = NTFS_I(vi);
-	vol = ni->vol;
-
-	/* $MFT/$DATA must have its complete runlist in memory at all times. */
-	BUG_ON(!ni->runlist.rl && !ni->mft_no && !NInoAttr(ni));
-
-	blocksize = vol->sb->s_blocksize;
-	blocksize_bits = vol->sb->s_blocksize_bits;
+	vcn = NTFS_PIDX_TO_CLU(vol, folio_index);
 
-	head = folio_buffers(folio);
-	if (!head)
-		head = create_empty_buffers(folio, blocksize, 0);
-	bh = head;
+	down_read(&ni->runlist.lock);
+	lcn = ntfs_attr_vcn_to_lcn_nolock(ni, vcn, false);
+	up_read(&ni->runlist.lock);
 
-	/*
-	 * We may be racing with truncate.  To avoid some of the problems we
-	 * now take a snapshot of the various sizes and use those for the whole
-	 * of the function.  In case of an extending truncate it just means we
-	 * may leave some buffers unmapped which are now allocated.  This is
-	 * not a problem since these buffers will just get mapped when a write
-	 * occurs.  In case of a shrinking truncate, we will detect this later
-	 * on due to the runlist being incomplete and if the folio is being
-	 * fully truncated, truncate will throw it away as soon as we unlock
-	 * it so no need to worry what we do with it.
-	 */
-	iblock = (s64)folio->index << (PAGE_SHIFT - blocksize_bits);
-	read_lock_irqsave(&ni->size_lock, flags);
-	lblock = (ni->allocated_size + blocksize - 1) >> blocksize_bits;
-	init_size = ni->initialized_size;
-	i_size = i_size_read(vi);
-	read_unlock_irqrestore(&ni->size_lock, flags);
-	if (unlikely(init_size > i_size)) {
-		/* Race with shrinking truncate. */
-		init_size = i_size;
-	}
-	zblock = (init_size + blocksize - 1) >> blocksize_bits;
-
-	/* Loop through all the buffers in the folio. */
-	rl = NULL;
-	nr = i = 0;
-	do {
-		int err = 0;
-
-		if (unlikely(buffer_uptodate(bh)))
-			continue;
-		if (unlikely(buffer_mapped(bh))) {
-			arr[nr++] = bh;
-			continue;
-		}
-		bh->b_bdev = vol->sb->s_bdev;
-		/* Is the block within the allowed limits? */
-		if (iblock < lblock) {
-			bool is_retry = false;
-
-			/* Convert iblock into corresponding vcn and offset. */
-			vcn = (VCN)iblock << blocksize_bits >>
-					vol->cluster_size_bits;
-			vcn_ofs = ((VCN)iblock << blocksize_bits) &
-					vol->cluster_size_mask;
-			if (!rl) {
-lock_retry_remap:
-				down_read(&ni->runlist.lock);
-				rl = ni->runlist.rl;
-			}
-			if (likely(rl != NULL)) {
-				/* Seek to element containing target vcn. */
-				while (rl->length && rl[1].vcn <= vcn)
-					rl++;
-				lcn = ntfs_rl_vcn_to_lcn(rl, vcn);
-			} else
-				lcn = LCN_RL_NOT_MAPPED;
-			/* Successful remap. */
-			if (lcn >= 0) {
-				/* Setup buffer head to correct block. */
-				bh->b_blocknr = ((lcn << vol->cluster_size_bits)
-						+ vcn_ofs) >> blocksize_bits;
-				set_buffer_mapped(bh);
-				/* Only read initialized data blocks. */
-				if (iblock < zblock) {
-					arr[nr++] = bh;
-					continue;
-				}
-				/* Fully non-initialized data block, zero it. */
-				goto handle_zblock;
-			}
-			/* It is a hole, need to zero it. */
-			if (lcn == LCN_HOLE)
-				goto handle_hole;
-			/* If first try and runlist unmapped, map and retry. */
-			if (!is_retry && lcn == LCN_RL_NOT_MAPPED) {
-				is_retry = true;
-				/*
-				 * Attempt to map runlist, dropping lock for
-				 * the duration.
-				 */
-				up_read(&ni->runlist.lock);
-				err = ntfs_map_runlist(ni, vcn);
-				if (likely(!err))
-					goto lock_retry_remap;
-				rl = NULL;
-			} else if (!rl)
-				up_read(&ni->runlist.lock);
-			/*
-			 * If buffer is outside the runlist, treat it as a
-			 * hole.  This can happen due to concurrent truncate
-			 * for example.
-			 */
-			if (err == -ENOENT || lcn == LCN_ENOENT) {
-				err = 0;
-				goto handle_hole;
-			}
-			/* Hard error, zero out region. */
-			if (!err)
-				err = -EIO;
-			bh->b_blocknr = -1;
-			folio_set_error(folio);
-			ntfs_error(vol->sb, "Failed to read from inode 0x%lx, "
-					"attribute type 0x%x, vcn 0x%llx, "
-					"offset 0x%x because its location on "
-					"disk could not be determined%s "
-					"(error code %i).", ni->mft_no,
-					ni->type, (unsigned long long)vcn,
-					vcn_ofs, is_retry ? " even after "
-					"retrying" : "", err);
-		}
-		/*
-		 * Either iblock was outside lblock limits or
-		 * ntfs_rl_vcn_to_lcn() returned error.  Just zero that portion
-		 * of the folio and set the buffer uptodate.
-		 */
-handle_hole:
-		bh->b_blocknr = -1UL;
-		clear_buffer_mapped(bh);
-handle_zblock:
-		folio_zero_range(folio, i * blocksize, blocksize);
-		if (likely(!err))
-			set_buffer_uptodate(bh);
-	} while (i++, iblock++, (bh = bh->b_this_page) != head);
-
-	/* Release the lock if we took it. */
-	if (rl)
-		up_read(&ni->runlist.lock);
-
-	/* Check we have at least one buffer ready for i/o. */
-	if (nr) {
-		struct buffer_head *tbh;
-
-		/* Lock the buffers. */
-		for (i = 0; i < nr; i++) {
-			tbh = arr[i];
-			lock_buffer(tbh);
-			tbh->b_end_io = ntfs_end_buffer_async_read;
-			set_buffer_async_read(tbh);
-		}
-		/* Finally, start i/o on the buffers. */
-		for (i = 0; i < nr; i++) {
-			tbh = arr[i];
-			if (likely(!buffer_uptodate(tbh)))
-				submit_bh(REQ_OP_READ, tbh);
-			else
-				ntfs_end_buffer_async_read(tbh, 1);
-		}
-		return 0;
-	}
-	/* No i/o was scheduled on any of the buffers. */
-	if (likely(!folio_test_error(folio)))
-		folio_mark_uptodate(folio);
-	else /* Signal synchronous i/o error. */
-		nr = -EIO;
-	folio_unlock(folio);
-	return nr;
+	return lcn;
 }
 
 /**
@@ -358,8 +40,8 @@ static int ntfs_read_block(struct folio *folio)
  *
  * For non-resident attributes, ntfs_read_folio() fills the @folio of the open
  * file @file by calling the ntfs version of the generic block_read_full_folio()
- * function, ntfs_read_block(), which in turn creates and reads in the buffers
- * associated with the folio asynchronously.
+ * function, which in turn creates and reads in the buffers associated with
+ * the folio asynchronously.
  *
  * For resident attributes, OTOH, ntfs_read_folio() fills @folio by copying the
  * data from the mft record (which at this stage is most likely in memory) and
@@ -371,37 +53,8 @@ static int ntfs_read_block(struct folio *folio)
  */
 static int ntfs_read_folio(struct file *file, struct folio *folio)
 {
-	struct page *page = &folio->page;
-	loff_t i_size;
-	struct inode *vi;
-	ntfs_inode *ni, *base_ni;
-	u8 *addr;
-	ntfs_attr_search_ctx *ctx;
-	MFT_RECORD *mrec;
-	unsigned long flags;
-	u32 attr_len;
-	int err = 0;
-
-retry_readpage:
-	BUG_ON(!PageLocked(page));
-	vi = page->mapping->host;
-	i_size = i_size_read(vi);
-	/* Is the page fully outside i_size? (truncate in progress) */
-	if (unlikely(page->index >= (i_size + PAGE_SIZE - 1) >>
-			PAGE_SHIFT)) {
-		zero_user(page, 0, PAGE_SIZE);
-		ntfs_debug("Read outside i_size - truncated?");
-		goto done;
-	}
-	/*
-	 * This can potentially happen because we clear PageUptodate() during
-	 * ntfs_writepage() of MstProtected() attributes.
-	 */
-	if (PageUptodate(page)) {
-		unlock_page(page);
-		return 0;
-	}
-	ni = NTFS_I(vi);
+	struct ntfs_inode *ni = NTFS_I(folio->mapping->host);
+
 	/*
 	 * Only $DATA attributes can be encrypted and only unnamed $DATA
 	 * attributes can be compressed.  Index root can have the flags set but
@@ -413,1099 +66,194 @@ static int ntfs_read_folio(struct file *file, struct folio *folio)
 	if (ni->type != AT_INDEX_ALLOCATION) {
 		/* If attribute is encrypted, deny access, just like NT4. */
 		if (NInoEncrypted(ni)) {
-			BUG_ON(ni->type != AT_DATA);
-			err = -EACCES;
-			goto err_out;
+			folio_unlock(folio);
+			return -EACCES;
 		}
 		/* Compressed data streams are handled in compress.c. */
-		if (NInoNonResident(ni) && NInoCompressed(ni)) {
-			BUG_ON(ni->type != AT_DATA);
-			BUG_ON(ni->name_len);
-			return ntfs_read_compressed_block(page);
-		}
-	}
-	/* NInoNonResident() == NInoIndexAllocPresent() */
-	if (NInoNonResident(ni)) {
-		/* Normal, non-resident data stream. */
-		return ntfs_read_block(folio);
-	}
-	/*
-	 * Attribute is resident, implying it is not compressed or encrypted.
-	 * This also means the attribute is smaller than an mft record and
-	 * hence smaller than a page, so can simply zero out any pages with
-	 * index above 0.  Note the attribute can actually be marked compressed
-	 * but if it is resident the actual data is not compressed so we are
-	 * ok to ignore the compressed flag here.
-	 */
-	if (unlikely(page->index > 0)) {
-		zero_user(page, 0, PAGE_SIZE);
-		goto done;
-	}
-	if (!NInoAttr(ni))
-		base_ni = ni;
-	else
-		base_ni = ni->ext.base_ntfs_ino;
-	/* Map, pin, and lock the mft record. */
-	mrec = map_mft_record(base_ni);
-	if (IS_ERR(mrec)) {
-		err = PTR_ERR(mrec);
-		goto err_out;
-	}
-	/*
-	 * If a parallel write made the attribute non-resident, drop the mft
-	 * record and retry the read_folio.
-	 */
-	if (unlikely(NInoNonResident(ni))) {
-		unmap_mft_record(base_ni);
-		goto retry_readpage;
+		if (NInoNonResident(ni) && NInoCompressed(ni))
+			return ntfs_read_compressed_block(folio);
 	}
-	ctx = ntfs_attr_get_search_ctx(base_ni, mrec);
-	if (unlikely(!ctx)) {
-		err = -ENOMEM;
-		goto unm_err_out;
-	}
-	err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
-			CASE_SENSITIVE, 0, NULL, 0, ctx);
-	if (unlikely(err))
-		goto put_unm_err_out;
-	attr_len = le32_to_cpu(ctx->attr->data.resident.value_length);
-	read_lock_irqsave(&ni->size_lock, flags);
-	if (unlikely(attr_len > ni->initialized_size))
-		attr_len = ni->initialized_size;
-	i_size = i_size_read(vi);
-	read_unlock_irqrestore(&ni->size_lock, flags);
-	if (unlikely(attr_len > i_size)) {
-		/* Race with shrinking truncate. */
-		attr_len = i_size;
-	}
-	addr = kmap_atomic(page);
-	/* Copy the data to the page. */
-	memcpy(addr, (u8*)ctx->attr +
-			le16_to_cpu(ctx->attr->data.resident.value_offset),
-			attr_len);
-	/* Zero the remainder of the page. */
-	memset(addr + attr_len, 0, PAGE_SIZE - attr_len);
-	flush_dcache_page(page);
-	kunmap_atomic(addr);
-put_unm_err_out:
-	ntfs_attr_put_search_ctx(ctx);
-unm_err_out:
-	unmap_mft_record(base_ni);
-done:
-	SetPageUptodate(page);
-err_out:
-	unlock_page(page);
-	return err;
-}
 
-#ifdef NTFS_RW
+	iomap_bio_read_folio(folio, &ntfs_read_iomap_ops);
+	return 0;
+}
 
-/**
- * ntfs_write_block - write a @folio to the backing store
- * @folio:	page cache folio to write out
- * @wbc:	writeback control structure
- *
- * This function is for writing folios belonging to non-resident, non-mst
- * protected attributes to their backing store.
- *
- * For a folio with buffers, map and write the dirty buffers asynchronously
- * under folio writeback. For a folio without buffers, create buffers for the
- * folio, then proceed as above.
- *
- * If a folio doesn't have buffers the folio dirty state is definitive. If
- * a folio does have buffers, the folio dirty state is just a hint,
- * and the buffer dirty state is definitive. (A hint which has rules:
- * dirty buffers against a clean folio is illegal. Other combinations are
- * legal and need to be handled. In particular a dirty folio containing
- * clean buffers for example.)
- *
- * Return 0 on success and -errno on error.
- *
- * Based on ntfs_read_block() and __block_write_full_folio().
- */
-static int ntfs_write_block(struct folio *folio, struct writeback_control *wbc)
+static int ntfs_write_mft_block(struct ntfs_inode *ni, struct folio *folio,
+		struct writeback_control *wbc)
 {
-	VCN vcn;
-	LCN lcn;
-	s64 initialized_size;
-	loff_t i_size;
-	sector_t block, dblock, iblock;
-	struct inode *vi;
-	ntfs_inode *ni;
-	ntfs_volume *vol;
-	runlist_element *rl;
-	struct buffer_head *bh, *head;
-	unsigned long flags;
-	unsigned int blocksize, vcn_ofs;
-	int err;
-	bool need_end_writeback;
-	unsigned char blocksize_bits;
-
-	vi = folio->mapping->host;
-	ni = NTFS_I(vi);
-	vol = ni->vol;
-
-	ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index "
-			"0x%lx.", ni->mft_no, ni->type, folio->index);
-
-	BUG_ON(!NInoNonResident(ni));
-	BUG_ON(NInoMstProtected(ni));
-	blocksize = vol->sb->s_blocksize;
-	blocksize_bits = vol->sb->s_blocksize_bits;
-	head = folio_buffers(folio);
-	if (!head) {
-		BUG_ON(!folio_test_uptodate(folio));
-		head = create_empty_buffers(folio, blocksize,
-				(1 << BH_Uptodate) | (1 << BH_Dirty));
+	struct inode *vi = VFS_I(ni);
+	struct ntfs_volume *vol = ni->vol;
+	u8 *kaddr;
+	struct ntfs_inode *locked_nis[PAGE_SIZE / NTFS_BLOCK_SIZE];
+	int nr_locked_nis = 0, err = 0, mft_ofs, prev_mft_ofs;
+	struct bio *bio = NULL;
+	unsigned long mft_no;
+	struct ntfs_inode *tni;
+	s64 lcn;
+	s64 vcn = NTFS_PIDX_TO_CLU(vol, folio->index);
+	s64 end_vcn = NTFS_B_TO_CLU(vol, ni->allocated_size);
+	unsigned int folio_sz;
+	struct runlist_element *rl;
+
+	ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, folio index 0x%lx.",
+			vi->i_ino, ni->type, folio->index);
+
+	lcn = ntfs_convert_folio_index_into_lcn(vol, ni, folio->index);
+	if (lcn <= LCN_HOLE) {
+		folio_start_writeback(folio);
+		folio_unlock(folio);
+		folio_end_writeback(folio);
+		return -EIO;
 	}
-	bh = head;
-
-	/* NOTE: Different naming scheme to ntfs_read_block()! */
-
-	/* The first block in the folio. */
-	block = (s64)folio->index << (PAGE_SHIFT - blocksize_bits);
-
-	read_lock_irqsave(&ni->size_lock, flags);
-	i_size = i_size_read(vi);
-	initialized_size = ni->initialized_size;
-	read_unlock_irqrestore(&ni->size_lock, flags);
-
-	/* The first out of bounds block for the data size. */
-	dblock = (i_size + blocksize - 1) >> blocksize_bits;
-
-	/* The last (fully or partially) initialized block. */
-	iblock = initialized_size >> blocksize_bits;
-
-	/*
-	 * Be very careful.  We have no exclusion from block_dirty_folio
-	 * here, and the (potentially unmapped) buffers may become dirty at
-	 * any time.  If a buffer becomes dirty here after we've inspected it
-	 * then we just miss that fact, and the folio stays dirty.
-	 *
-	 * Buffers outside i_size may be dirtied by block_dirty_folio;
-	 * handle that here by just cleaning them.
-	 */
 
-	/*
-	 * Loop through all the buffers in the folio, mapping all the dirty
-	 * buffers to disk addresses and handling any aliases from the
-	 * underlying block device's mapping.
-	 */
-	rl = NULL;
-	err = 0;
-	do {
-		bool is_retry = false;
-
-		if (unlikely(block >= dblock)) {
-			/*
-			 * Mapped buffers outside i_size will occur, because
-			 * this folio can be outside i_size when there is a
-			 * truncate in progress. The contents of such buffers
-			 * were zeroed by ntfs_writepage().
-			 *
-			 * FIXME: What about the small race window where
-			 * ntfs_writepage() has not done any clearing because
-			 * the folio was within i_size but before we get here,
-			 * vmtruncate() modifies i_size?
-			 */
-			clear_buffer_dirty(bh);
-			set_buffer_uptodate(bh);
-			continue;
-		}
-
-		/* Clean buffers are not written out, so no need to map them. */
-		if (!buffer_dirty(bh))
-			continue;
+	/* Map folio so we can access its contents. */
+	kaddr = kmap_local_folio(folio, 0);
+	/* Clear the page uptodate flag whilst the mst fixups are applied. */
+	folio_clear_uptodate(folio);
+
+	for (mft_ofs = 0; mft_ofs < PAGE_SIZE && vcn < end_vcn;
+	     mft_ofs += vol->mft_record_size) {
+		/* Get the mft record number. */
+		mft_no = (((s64)folio->index << PAGE_SHIFT) + mft_ofs) >>
+			vol->mft_record_size_bits;
+		vcn = NTFS_MFT_NR_TO_CLU(vol, mft_no);
+		/* Check whether to write this mft record. */
+		tni = NULL;
+		if (ntfs_may_write_mft_record(vol, mft_no,
+					(struct mft_record *)(kaddr + mft_ofs), &tni)) {
+			unsigned int mft_record_off = 0;
+			s64 vcn_off = vcn;
 
-		/* Make sure we have enough initialized size. */
-		if (unlikely((block >= iblock) &&
-				(initialized_size < i_size))) {
-			/*
-			 * If this folio is fully outside initialized
-			 * size, zero out all folios between the current
-			 * initialized size and the current folio. Just
-			 * use ntfs_read_folio() to do the zeroing
-			 * transparently.
-			 */
-			if (block > iblock) {
-				// TODO:
-				// For each folio do:
-				// - read_cache_folio()
-				// Again for each folio do:
-				// - wait_on_folio_locked()
-				// - Check (folio_test_uptodate(folio) &&
-				//		!folio_test_error(folio))
-				// Update initialized size in the attribute and
-				// in the inode.
-				// Again, for each folio do:
-				//	block_dirty_folio();
-				// folio_put()
-				// We don't need to wait on the writes.
-				// Update iblock.
-			}
 			/*
-			 * The current folio straddles initialized size. Zero
-			 * all non-uptodate buffers and set them uptodate (and
-			 * dirty?). Note, there aren't any non-uptodate buffers
-			 * if the folio is uptodate.
-			 * FIXME: For an uptodate folio, the buffers may need to
-			 * be written out because they were not initialized on
-			 * disk before.
+			 * Skip $MFT extent mft records and let them being written
+			 * by writeback to avioid deadlocks. the $MFT runlist
+			 * lock must be taken before $MFT extent mrec_lock is taken.
 			 */
-			if (!folio_test_uptodate(folio)) {
-				// TODO:
-				// Zero any non-uptodate buffers up to i_size.
-				// Set them uptodate and dirty.
-			}
-			// TODO:
-			// Update initialized size in the attribute and in the
-			// inode (up to i_size).
-			// Update iblock.
-			// FIXME: This is inefficient. Try to batch the two
-			// size changes to happen in one go.
-			ntfs_error(vol->sb, "Writing beyond initialized size "
-					"is not supported yet. Sorry.");
-			err = -EOPNOTSUPP;
-			break;
-			// Do NOT set_buffer_new() BUT DO clear buffer range
-			// outside write request range.
-			// set_buffer_uptodate() on complete buffers as well as
-			// set_buffer_dirty().
-		}
-
-		/* No need to map buffers that are already mapped. */
-		if (buffer_mapped(bh))
-			continue;
-
-		/* Unmapped, dirty buffer. Need to map it. */
-		bh->b_bdev = vol->sb->s_bdev;
-
-		/* Convert block into corresponding vcn and offset. */
-		vcn = (VCN)block << blocksize_bits;
-		vcn_ofs = vcn & vol->cluster_size_mask;
-		vcn >>= vol->cluster_size_bits;
-		if (!rl) {
-lock_retry_remap:
-			down_read(&ni->runlist.lock);
-			rl = ni->runlist.rl;
-		}
-		if (likely(rl != NULL)) {
-			/* Seek to element containing target vcn. */
-			while (rl->length && rl[1].vcn <= vcn)
-				rl++;
-			lcn = ntfs_rl_vcn_to_lcn(rl, vcn);
-		} else
-			lcn = LCN_RL_NOT_MAPPED;
-		/* Successful remap. */
-		if (lcn >= 0) {
-			/* Setup buffer head to point to correct block. */
-			bh->b_blocknr = ((lcn << vol->cluster_size_bits) +
-					vcn_ofs) >> blocksize_bits;
-			set_buffer_mapped(bh);
-			continue;
-		}
-		/* It is a hole, need to instantiate it. */
-		if (lcn == LCN_HOLE) {
-			u8 *kaddr;
-			unsigned long *bpos, *bend;
-
-			/* Check if the buffer is zero. */
-			kaddr = kmap_local_folio(folio, bh_offset(bh));
-			bpos = (unsigned long *)kaddr;
-			bend = (unsigned long *)(kaddr + blocksize);
-			do {
-				if (unlikely(*bpos))
-					break;
-			} while (likely(++bpos < bend));
-			kunmap_local(kaddr);
-			if (bpos == bend) {
-				/*
-				 * Buffer is zero and sparse, no need to write
-				 * it.
-				 */
-				bh->b_blocknr = -1;
-				clear_buffer_dirty(bh);
+			if (tni && tni->nr_extents < 0 &&
+				tni->ext.base_ntfs_ino == NTFS_I(vol->mft_ino)) {
+				mutex_unlock(&tni->mrec_lock);
+				atomic_dec(&tni->count);
+				iput(vol->mft_ino);
 				continue;
 			}
-			// TODO: Instantiate the hole.
-			// clear_buffer_new(bh);
-			// clean_bdev_bh_alias(bh);
-			ntfs_error(vol->sb, "Writing into sparse regions is "
-					"not supported yet. Sorry.");
-			err = -EOPNOTSUPP;
-			break;
-		}
-		/* If first try and runlist unmapped, map and retry. */
-		if (!is_retry && lcn == LCN_RL_NOT_MAPPED) {
-			is_retry = true;
-			/*
-			 * Attempt to map runlist, dropping lock for
-			 * the duration.
-			 */
-			up_read(&ni->runlist.lock);
-			err = ntfs_map_runlist(ni, vcn);
-			if (likely(!err))
-				goto lock_retry_remap;
-			rl = NULL;
-		} else if (!rl)
-			up_read(&ni->runlist.lock);
-		/*
-		 * If buffer is outside the runlist, truncate has cut it out
-		 * of the runlist.  Just clean and clear the buffer and set it
-		 * uptodate so it can get discarded by the VM.
-		 */
-		if (err == -ENOENT || lcn == LCN_ENOENT) {
-			bh->b_blocknr = -1;
-			clear_buffer_dirty(bh);
-			folio_zero_range(folio, bh_offset(bh), blocksize);
-			set_buffer_uptodate(bh);
-			err = 0;
-			continue;
-		}
-		/* Failed to map the buffer, even after retrying. */
-		if (!err)
-			err = -EIO;
-		bh->b_blocknr = -1;
-		ntfs_error(vol->sb, "Failed to write to inode 0x%lx, "
-				"attribute type 0x%x, vcn 0x%llx, offset 0x%x "
-				"because its location on disk could not be "
-				"determined%s (error code %i).", ni->mft_no,
-				ni->type, (unsigned long long)vcn,
-				vcn_ofs, is_retry ? " even after "
-				"retrying" : "", err);
-		break;
-	} while (block++, (bh = bh->b_this_page) != head);
-
-	/* Release the lock if we took it. */
-	if (rl)
-		up_read(&ni->runlist.lock);
-
-	/* For the error case, need to reset bh to the beginning. */
-	bh = head;
-
-	/* Just an optimization, so ->read_folio() is not called later. */
-	if (unlikely(!folio_test_uptodate(folio))) {
-		int uptodate = 1;
-		do {
-			if (!buffer_uptodate(bh)) {
-				uptodate = 0;
-				bh = head;
-				break;
-			}
-		} while ((bh = bh->b_this_page) != head);
-		if (uptodate)
-			folio_mark_uptodate(folio);
-	}
 
-	/* Setup all mapped, dirty buffers for async write i/o. */
-	do {
-		if (buffer_mapped(bh) && buffer_dirty(bh)) {
-			lock_buffer(bh);
-			if (test_clear_buffer_dirty(bh)) {
-				BUG_ON(!buffer_uptodate(bh));
-				mark_buffer_async_write(bh);
-			} else
-				unlock_buffer(bh);
-		} else if (unlikely(err)) {
-			/*
-			 * For the error case. The buffer may have been set
-			 * dirty during attachment to a dirty folio.
-			 */
-			if (err != -ENOMEM)
-				clear_buffer_dirty(bh);
-		}
-	} while ((bh = bh->b_this_page) != head);
-
-	if (unlikely(err)) {
-		// TODO: Remove the -EOPNOTSUPP check later on...
-		if (unlikely(err == -EOPNOTSUPP))
-			err = 0;
-		else if (err == -ENOMEM) {
-			ntfs_warning(vol->sb, "Error allocating memory. "
-					"Redirtying folio so we try again "
-					"later.");
 			/*
-			 * Put the folio back on mapping->dirty_pages, but
-			 * leave its buffer's dirty state as-is.
+			 * The record should be written.  If a locked ntfs
+			 * inode was returned, add it to the array of locked
+			 * ntfs inodes.
 			 */
-			folio_redirty_for_writepage(wbc, folio);
-			err = 0;
-		} else
-			folio_set_error(folio);
-	}
+			if (tni)
+				locked_nis[nr_locked_nis++] = tni;
 
-	BUG_ON(folio_test_writeback(folio));
-	folio_start_writeback(folio);	/* Keeps try_to_free_buffers() away. */
+			if (bio && (mft_ofs != prev_mft_ofs + vol->mft_record_size)) {
+flush_bio:
+				flush_dcache_folio(folio);
+				submit_bio_wait(bio);
+				bio_put(bio);
+				bio = NULL;
+			}
 
-	/* Submit the prepared buffers for i/o. */
-	need_end_writeback = true;
-	do {
-		struct buffer_head *next = bh->b_this_page;
-		if (buffer_async_write(bh)) {
-			submit_bh(REQ_OP_WRITE, bh);
-			need_end_writeback = false;
-		}
-		bh = next;
-	} while (bh != head);
-	folio_unlock(folio);
+			if (vol->cluster_size < folio_size(folio)) {
+				down_write(&ni->runlist.lock);
+				rl = ntfs_attr_vcn_to_rl(ni, vcn_off, &lcn);
+				up_write(&ni->runlist.lock);
+				if (IS_ERR(rl) || lcn < 0) {
+					err = -EIO;
+					goto unm_done;
+				}
 
-	/* If no i/o was started, need to end writeback here. */
-	if (unlikely(need_end_writeback))
-		folio_end_writeback(folio);
+				if (bio &&
+				   (bio_end_sector(bio) >> (vol->cluster_size_bits - 9)) !=
+				    lcn) {
+					flush_dcache_folio(folio);
+					submit_bio_wait(bio);
+					bio_put(bio);
+					bio = NULL;
+				}
+			}
 
-	ntfs_debug("Done.");
-	return err;
-}
+			if (!bio) {
+				unsigned int off;
 
-/**
- * ntfs_write_mst_block - write a @page to the backing store
- * @page:	page cache page to write out
- * @wbc:	writeback control structure
- *
- * This function is for writing pages belonging to non-resident, mst protected
- * attributes to their backing store.  The only supported attributes are index
- * allocation and $MFT/$DATA.  Both directory inodes and index inodes are
- * supported for the index allocation case.
- *
- * The page must remain locked for the duration of the write because we apply
- * the mst fixups, write, and then undo the fixups, so if we were to unlock the
- * page before undoing the fixups, any other user of the page will see the
- * page contents as corrupt.
- *
- * We clear the page uptodate flag for the duration of the function to ensure
- * exclusion for the $MFT/$DATA case against someone mapping an mft record we
- * are about to apply the mst fixups to.
- *
- * Return 0 on success and -errno on error.
- *
- * Based on ntfs_write_block(), ntfs_mft_writepage(), and
- * write_mft_record_nolock().
- */
-static int ntfs_write_mst_block(struct page *page,
-		struct writeback_control *wbc)
-{
-	sector_t block, dblock, rec_block;
-	struct inode *vi = page->mapping->host;
-	ntfs_inode *ni = NTFS_I(vi);
-	ntfs_volume *vol = ni->vol;
-	u8 *kaddr;
-	unsigned int rec_size = ni->itype.index.block_size;
-	ntfs_inode *locked_nis[PAGE_SIZE / NTFS_BLOCK_SIZE];
-	struct buffer_head *bh, *head, *tbh, *rec_start_bh;
-	struct buffer_head *bhs[MAX_BUF_PER_PAGE];
-	runlist_element *rl;
-	int i, nr_locked_nis, nr_recs, nr_bhs, max_bhs, bhs_per_rec, err, err2;
-	unsigned bh_size, rec_size_bits;
-	bool sync, is_mft, page_is_dirty, rec_is_dirty;
-	unsigned char bh_size_bits;
-
-	if (WARN_ON(rec_size < NTFS_BLOCK_SIZE))
-		return -EINVAL;
-
-	ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index "
-			"0x%lx.", vi->i_ino, ni->type, page->index);
-	BUG_ON(!NInoNonResident(ni));
-	BUG_ON(!NInoMstProtected(ni));
-	is_mft = (S_ISREG(vi->i_mode) && !vi->i_ino);
-	/*
-	 * NOTE: ntfs_write_mst_block() would be called for $MFTMirr if a page
-	 * in its page cache were to be marked dirty.  However this should
-	 * never happen with the current driver and considering we do not
-	 * handle this case here we do want to BUG(), at least for now.
-	 */
-	BUG_ON(!(is_mft || S_ISDIR(vi->i_mode) ||
-			(NInoAttr(ni) && ni->type == AT_INDEX_ALLOCATION)));
-	bh_size = vol->sb->s_blocksize;
-	bh_size_bits = vol->sb->s_blocksize_bits;
-	max_bhs = PAGE_SIZE / bh_size;
-	BUG_ON(!max_bhs);
-	BUG_ON(max_bhs > MAX_BUF_PER_PAGE);
-
-	/* Were we called for sync purposes? */
-	sync = (wbc->sync_mode == WB_SYNC_ALL);
-
-	/* Make sure we have mapped buffers. */
-	bh = head = page_buffers(page);
-	BUG_ON(!bh);
-
-	rec_size_bits = ni->itype.index.block_size_bits;
-	BUG_ON(!(PAGE_SIZE >> rec_size_bits));
-	bhs_per_rec = rec_size >> bh_size_bits;
-	BUG_ON(!bhs_per_rec);
-
-	/* The first block in the page. */
-	rec_block = block = (sector_t)page->index <<
-			(PAGE_SHIFT - bh_size_bits);
-
-	/* The first out of bounds block for the data size. */
-	dblock = (i_size_read(vi) + bh_size - 1) >> bh_size_bits;
-
-	rl = NULL;
-	err = err2 = nr_bhs = nr_recs = nr_locked_nis = 0;
-	page_is_dirty = rec_is_dirty = false;
-	rec_start_bh = NULL;
-	do {
-		bool is_retry = false;
-
-		if (likely(block < rec_block)) {
-			if (unlikely(block >= dblock)) {
-				clear_buffer_dirty(bh);
-				set_buffer_uptodate(bh);
-				continue;
-			}
-			/*
-			 * This block is not the first one in the record.  We
-			 * ignore the buffer's dirty state because we could
-			 * have raced with a parallel mark_ntfs_record_dirty().
-			 */
-			if (!rec_is_dirty)
-				continue;
-			if (unlikely(err2)) {
-				if (err2 != -ENOMEM)
-					clear_buffer_dirty(bh);
-				continue;
-			}
-		} else /* if (block == rec_block) */ {
-			BUG_ON(block > rec_block);
-			/* This block is the first one in the record. */
-			rec_block += bhs_per_rec;
-			err2 = 0;
-			if (unlikely(block >= dblock)) {
-				clear_buffer_dirty(bh);
-				continue;
-			}
-			if (!buffer_dirty(bh)) {
-				/* Clean records are not written out. */
-				rec_is_dirty = false;
-				continue;
-			}
-			rec_is_dirty = true;
-			rec_start_bh = bh;
-		}
-		/* Need to map the buffer if it is not mapped already. */
-		if (unlikely(!buffer_mapped(bh))) {
-			VCN vcn;
-			LCN lcn;
-			unsigned int vcn_ofs;
-
-			bh->b_bdev = vol->sb->s_bdev;
-			/* Obtain the vcn and offset of the current block. */
-			vcn = (VCN)block << bh_size_bits;
-			vcn_ofs = vcn & vol->cluster_size_mask;
-			vcn >>= vol->cluster_size_bits;
-			if (!rl) {
-lock_retry_remap:
-				down_read(&ni->runlist.lock);
-				rl = ni->runlist.rl;
+				off = ((mft_no << vol->mft_record_size_bits) +
+				       mft_record_off) & vol->cluster_size_mask;
+
+				bio = bio_alloc(vol->sb->s_bdev, 1, REQ_OP_WRITE,
+						GFP_NOIO);
+				bio->bi_iter.bi_sector =
+					NTFS_B_TO_SECTOR(vol, NTFS_CLU_TO_B(vol, lcn) + off);
 			}
-			if (likely(rl != NULL)) {
-				/* Seek to element containing target vcn. */
-				while (rl->length && rl[1].vcn <= vcn)
-					rl++;
-				lcn = ntfs_rl_vcn_to_lcn(rl, vcn);
-			} else
-				lcn = LCN_RL_NOT_MAPPED;
-			/* Successful remap. */
-			if (likely(lcn >= 0)) {
-				/* Setup buffer head to correct block. */
-				bh->b_blocknr = ((lcn <<
-						vol->cluster_size_bits) +
-						vcn_ofs) >> bh_size_bits;
-				set_buffer_mapped(bh);
-			} else {
-				/*
-				 * Remap failed.  Retry to map the runlist once
-				 * unless we are working on $MFT which always
-				 * has the whole of its runlist in memory.
-				 */
-				if (!is_mft && !is_retry &&
-						lcn == LCN_RL_NOT_MAPPED) {
-					is_retry = true;
-					/*
-					 * Attempt to map runlist, dropping
-					 * lock for the duration.
-					 */
-					up_read(&ni->runlist.lock);
-					err2 = ntfs_map_runlist(ni, vcn);
-					if (likely(!err2))
-						goto lock_retry_remap;
-					if (err2 == -ENOMEM)
-						page_is_dirty = true;
-					lcn = err2;
-				} else {
-					err2 = -EIO;
-					if (!rl)
-						up_read(&ni->runlist.lock);
-				}
-				/* Hard error.  Abort writing this record. */
-				if (!err || err == -ENOMEM)
-					err = err2;
-				bh->b_blocknr = -1;
-				ntfs_error(vol->sb, "Cannot write ntfs record "
-						"0x%llx (inode 0x%lx, "
-						"attribute type 0x%x) because "
-						"its location on disk could "
-						"not be determined (error "
-						"code %lli).",
-						(long long)block <<
-						bh_size_bits >>
-						vol->mft_record_size_bits,
-						ni->mft_no, ni->type,
-						(long long)lcn);
-				/*
-				 * If this is not the first buffer, remove the
-				 * buffers in this record from the list of
-				 * buffers to write and clear their dirty bit
-				 * if not error -ENOMEM.
-				 */
-				if (rec_start_bh != bh) {
-					while (bhs[--nr_bhs] != rec_start_bh)
-						;
-					if (err2 != -ENOMEM) {
-						do {
-							clear_buffer_dirty(
-								rec_start_bh);
-						} while ((rec_start_bh =
-								rec_start_bh->
-								b_this_page) !=
-								bh);
-					}
-				}
-				continue;
+
+			if (vol->cluster_size == NTFS_BLOCK_SIZE &&
+			    (mft_record_off ||
+			     rl->length - (vcn_off - rl->vcn) == 1 ||
+			     mft_ofs + NTFS_BLOCK_SIZE >= PAGE_SIZE))
+				folio_sz = NTFS_BLOCK_SIZE;
+			else
+				folio_sz = vol->mft_record_size;
+			if (!bio_add_folio(bio, folio, folio_sz,
+					   mft_ofs + mft_record_off)) {
+				err = -EIO;
+				bio_put(bio);
+				goto unm_done;
 			}
-		}
-		BUG_ON(!buffer_uptodate(bh));
-		BUG_ON(nr_bhs >= max_bhs);
-		bhs[nr_bhs++] = bh;
-	} while (block++, (bh = bh->b_this_page) != head);
-	if (unlikely(rl))
-		up_read(&ni->runlist.lock);
-	/* If there were no dirty buffers, we are done. */
-	if (!nr_bhs)
-		goto done;
-	/* Map the page so we can access its contents. */
-	kaddr = kmap(page);
-	/* Clear the page uptodate flag whilst the mst fixups are applied. */
-	BUG_ON(!PageUptodate(page));
-	ClearPageUptodate(page);
-	for (i = 0; i < nr_bhs; i++) {
-		unsigned int ofs;
-
-		/* Skip buffers which are not at the beginning of records. */
-		if (i % bhs_per_rec)
-			continue;
-		tbh = bhs[i];
-		ofs = bh_offset(tbh);
-		if (is_mft) {
-			ntfs_inode *tni;
-			unsigned long mft_no;
-
-			/* Get the mft record number. */
-			mft_no = (((s64)page->index << PAGE_SHIFT) + ofs)
-					>> rec_size_bits;
-			/* Check whether to write this mft record. */
-			tni = NULL;
-			if (!ntfs_may_write_mft_record(vol, mft_no,
-					(MFT_RECORD*)(kaddr + ofs), &tni)) {
-				/*
-				 * The record should not be written.  This
-				 * means we need to redirty the page before
-				 * returning.
-				 */
-				page_is_dirty = true;
-				/*
-				 * Remove the buffers in this mft record from
-				 * the list of buffers to write.
-				 */
-				do {
-					bhs[i] = NULL;
-				} while (++i % bhs_per_rec);
-				continue;
+			mft_record_off += folio_sz;
+
+			if (mft_record_off != vol->mft_record_size) {
+				vcn_off++;
+				goto flush_bio;
 			}
-			/*
-			 * The record should be written.  If a locked ntfs
-			 * inode was returned, add it to the array of locked
-			 * ntfs inodes.
-			 */
-			if (tni)
-				locked_nis[nr_locked_nis++] = tni;
-		}
-		/* Apply the mst protection fixups. */
-		err2 = pre_write_mst_fixup((NTFS_RECORD*)(kaddr + ofs),
-				rec_size);
-		if (unlikely(err2)) {
-			if (!err || err == -ENOMEM)
-				err = -EIO;
-			ntfs_error(vol->sb, "Failed to apply mst fixups "
-					"(inode 0x%lx, attribute type 0x%x, "
-					"page index 0x%lx, page offset 0x%x)!"
-					"  Unmount and run chkdsk.", vi->i_ino,
-					ni->type, page->index, ofs);
-			/*
-			 * Mark all the buffers in this record clean as we do
-			 * not want to write corrupt data to disk.
-			 */
-			do {
-				clear_buffer_dirty(bhs[i]);
-				bhs[i] = NULL;
-			} while (++i % bhs_per_rec);
-			continue;
-		}
-		nr_recs++;
-	}
-	/* If no records are to be written out, we are done. */
-	if (!nr_recs)
-		goto unm_done;
-	flush_dcache_page(page);
-	/* Lock buffers and start synchronous write i/o on them. */
-	for (i = 0; i < nr_bhs; i++) {
-		tbh = bhs[i];
-		if (!tbh)
-			continue;
-		if (!trylock_buffer(tbh))
-			BUG();
-		/* The buffer dirty state is now irrelevant, just clean it. */
-		clear_buffer_dirty(tbh);
-		BUG_ON(!buffer_uptodate(tbh));
-		BUG_ON(!buffer_mapped(tbh));
-		get_bh(tbh);
-		tbh->b_end_io = end_buffer_write_sync;
-		submit_bh(REQ_OP_WRITE, tbh);
-	}
-	/* Synchronize the mft mirror now if not @sync. */
-	if (is_mft && !sync)
-		goto do_mirror;
-do_wait:
-	/* Wait on i/o completion of buffers. */
-	for (i = 0; i < nr_bhs; i++) {
-		tbh = bhs[i];
-		if (!tbh)
-			continue;
-		wait_on_buffer(tbh);
-		if (unlikely(!buffer_uptodate(tbh))) {
-			ntfs_error(vol->sb, "I/O error while writing ntfs "
-					"record buffer (inode 0x%lx, "
-					"attribute type 0x%x, page index "
-					"0x%lx, page offset 0x%lx)!  Unmount "
-					"and run chkdsk.", vi->i_ino, ni->type,
-					page->index, bh_offset(tbh));
-			if (!err || err == -ENOMEM)
-				err = -EIO;
-			/*
-			 * Set the buffer uptodate so the page and buffer
-			 * states do not become out of sync.
-			 */
-			set_buffer_uptodate(tbh);
-		}
-	}
-	/* If @sync, now synchronize the mft mirror. */
-	if (is_mft && sync) {
-do_mirror:
-		for (i = 0; i < nr_bhs; i++) {
-			unsigned long mft_no;
-			unsigned int ofs;
+			prev_mft_ofs = mft_ofs;
 
-			/*
-			 * Skip buffers which are not at the beginning of
-			 * records.
-			 */
-			if (i % bhs_per_rec)
-				continue;
-			tbh = bhs[i];
-			/* Skip removed buffers (and hence records). */
-			if (!tbh)
-				continue;
-			ofs = bh_offset(tbh);
-			/* Get the mft record number. */
-			mft_no = (((s64)page->index << PAGE_SHIFT) + ofs)
-					>> rec_size_bits;
 			if (mft_no < vol->mftmirr_size)
 				ntfs_sync_mft_mirror(vol, mft_no,
-						(MFT_RECORD*)(kaddr + ofs),
-						sync);
+						(struct mft_record *)(kaddr + mft_ofs));
 		}
-		if (!sync)
-			goto do_wait;
+
 	}
-	/* Remove the mst protection fixups again. */
-	for (i = 0; i < nr_bhs; i++) {
-		if (!(i % bhs_per_rec)) {
-			tbh = bhs[i];
-			if (!tbh)
-				continue;
-			post_write_mst_fixup((NTFS_RECORD*)(kaddr +
-					bh_offset(tbh)));
-		}
+
+	if (bio) {
+		flush_dcache_folio(folio);
+		submit_bio_wait(bio);
+		bio_put(bio);
 	}
-	flush_dcache_page(page);
+	flush_dcache_folio(folio);
 unm_done:
+	folio_mark_uptodate(folio);
+	kunmap_local(kaddr);
+
+	folio_start_writeback(folio);
+	folio_unlock(folio);
+	folio_end_writeback(folio);
+
 	/* Unlock any locked inodes. */
 	while (nr_locked_nis-- > 0) {
-		ntfs_inode *tni, *base_tni;
-		
+		struct ntfs_inode *base_tni;
+
 		tni = locked_nis[nr_locked_nis];
+		mutex_unlock(&tni->mrec_lock);
+
 		/* Get the base inode. */
 		mutex_lock(&tni->extent_lock);
 		if (tni->nr_extents >= 0)
 			base_tni = tni;
-		else {
+		else
 			base_tni = tni->ext.base_ntfs_ino;
-			BUG_ON(!base_tni);
-		}
 		mutex_unlock(&tni->extent_lock);
 		ntfs_debug("Unlocking %s inode 0x%lx.",
 				tni == base_tni ? "base" : "extent",
 				tni->mft_no);
-		mutex_unlock(&tni->mrec_lock);
 		atomic_dec(&tni->count);
 		iput(VFS_I(base_tni));
 	}
-	SetPageUptodate(page);
-	kunmap(page);
-done:
-	if (unlikely(err && err != -ENOMEM)) {
-		/*
-		 * Set page error if there is only one ntfs record in the page.
-		 * Otherwise we would loose per-record granularity.
-		 */
-		if (ni->itype.index.block_size == PAGE_SIZE)
-			SetPageError(page);
+
+	if (unlikely(err && err != -ENOMEM))
 		NVolSetErrors(vol);
-	}
-	if (page_is_dirty) {
-		ntfs_debug("Page still contains one or more dirty ntfs "
-				"records.  Redirtying the page starting at "
-				"record 0x%lx.", page->index <<
-				(PAGE_SHIFT - rec_size_bits));
-		redirty_page_for_writepage(wbc, page);
-		unlock_page(page);
-	} else {
-		/*
-		 * Keep the VM happy.  This must be done otherwise the
-		 * radix-tree tag PAGECACHE_TAG_DIRTY remains set even though
-		 * the page is clean.
-		 */
-		BUG_ON(PageWriteback(page));
-		set_page_writeback(page);
-		unlock_page(page);
-		end_page_writeback(page);
-	}
 	if (likely(!err))
 		ntfs_debug("Done.");
 	return err;
 }
 
-/**
- * ntfs_writepage - write a @page to the backing store
- * @page:	page cache page to write out
- * @wbc:	writeback control structure
- *
- * This is called from the VM when it wants to have a dirty ntfs page cache
- * page cleaned.  The VM has already locked the page and marked it clean.
- *
- * For non-resident attributes, ntfs_writepage() writes the @page by calling
- * the ntfs version of the generic block_write_full_folio() function,
- * ntfs_write_block(), which in turn if necessary creates and writes the
- * buffers associated with the page asynchronously.
- *
- * For resident attributes, OTOH, ntfs_writepage() writes the @page by copying
- * the data to the mft record (which at this stage is most likely in memory).
- * The mft record is then marked dirty and written out asynchronously via the
- * vfs inode dirty code path for the inode the mft record belongs to or via the
- * vm page dirty code path for the page the mft record is in.
- *
- * Based on ntfs_read_folio() and fs/buffer.c::block_write_full_folio().
- *
- * Return 0 on success and -errno on error.
- */
-static int ntfs_writepage(struct page *page, struct writeback_control *wbc)
-{
-	struct folio *folio = page_folio(page);
-	loff_t i_size;
-	struct inode *vi = folio->mapping->host;
-	ntfs_inode *base_ni = NULL, *ni = NTFS_I(vi);
-	char *addr;
-	ntfs_attr_search_ctx *ctx = NULL;
-	MFT_RECORD *m = NULL;
-	u32 attr_len;
-	int err;
-
-retry_writepage:
-	BUG_ON(!folio_test_locked(folio));
-	i_size = i_size_read(vi);
-	/* Is the folio fully outside i_size? (truncate in progress) */
-	if (unlikely(folio->index >= (i_size + PAGE_SIZE - 1) >>
-			PAGE_SHIFT)) {
-		/*
-		 * The folio may have dirty, unmapped buffers.  Make them
-		 * freeable here, so the page does not leak.
-		 */
-		block_invalidate_folio(folio, 0, folio_size(folio));
-		folio_unlock(folio);
-		ntfs_debug("Write outside i_size - truncated?");
-		return 0;
-	}
-	/*
-	 * Only $DATA attributes can be encrypted and only unnamed $DATA
-	 * attributes can be compressed.  Index root can have the flags set but
-	 * this means to create compressed/encrypted files, not that the
-	 * attribute is compressed/encrypted.  Note we need to check for
-	 * AT_INDEX_ALLOCATION since this is the type of both directory and
-	 * index inodes.
-	 */
-	if (ni->type != AT_INDEX_ALLOCATION) {
-		/* If file is encrypted, deny access, just like NT4. */
-		if (NInoEncrypted(ni)) {
-			folio_unlock(folio);
-			BUG_ON(ni->type != AT_DATA);
-			ntfs_debug("Denying write access to encrypted file.");
-			return -EACCES;
-		}
-		/* Compressed data streams are handled in compress.c. */
-		if (NInoNonResident(ni) && NInoCompressed(ni)) {
-			BUG_ON(ni->type != AT_DATA);
-			BUG_ON(ni->name_len);
-			// TODO: Implement and replace this with
-			// return ntfs_write_compressed_block(page);
-			folio_unlock(folio);
-			ntfs_error(vi->i_sb, "Writing to compressed files is "
-					"not supported yet.  Sorry.");
-			return -EOPNOTSUPP;
-		}
-		// TODO: Implement and remove this check.
-		if (NInoNonResident(ni) && NInoSparse(ni)) {
-			folio_unlock(folio);
-			ntfs_error(vi->i_sb, "Writing to sparse files is not "
-					"supported yet.  Sorry.");
-			return -EOPNOTSUPP;
-		}
-	}
-	/* NInoNonResident() == NInoIndexAllocPresent() */
-	if (NInoNonResident(ni)) {
-		/* We have to zero every time due to mmap-at-end-of-file. */
-		if (folio->index >= (i_size >> PAGE_SHIFT)) {
-			/* The folio straddles i_size. */
-			unsigned int ofs = i_size & (folio_size(folio) - 1);
-			folio_zero_segment(folio, ofs, folio_size(folio));
-		}
-		/* Handle mst protected attributes. */
-		if (NInoMstProtected(ni))
-			return ntfs_write_mst_block(page, wbc);
-		/* Normal, non-resident data stream. */
-		return ntfs_write_block(folio, wbc);
-	}
-	/*
-	 * Attribute is resident, implying it is not compressed, encrypted, or
-	 * mst protected.  This also means the attribute is smaller than an mft
-	 * record and hence smaller than a folio, so can simply return error on
-	 * any folios with index above 0.  Note the attribute can actually be
-	 * marked compressed but if it is resident the actual data is not
-	 * compressed so we are ok to ignore the compressed flag here.
-	 */
-	BUG_ON(folio_buffers(folio));
-	BUG_ON(!folio_test_uptodate(folio));
-	if (unlikely(folio->index > 0)) {
-		ntfs_error(vi->i_sb, "BUG()! folio->index (0x%lx) > 0.  "
-				"Aborting write.", folio->index);
-		BUG_ON(folio_test_writeback(folio));
-		folio_start_writeback(folio);
-		folio_unlock(folio);
-		folio_end_writeback(folio);
-		return -EIO;
-	}
-	if (!NInoAttr(ni))
-		base_ni = ni;
-	else
-		base_ni = ni->ext.base_ntfs_ino;
-	/* Map, pin, and lock the mft record. */
-	m = map_mft_record(base_ni);
-	if (IS_ERR(m)) {
-		err = PTR_ERR(m);
-		m = NULL;
-		ctx = NULL;
-		goto err_out;
-	}
-	/*
-	 * If a parallel write made the attribute non-resident, drop the mft
-	 * record and retry the writepage.
-	 */
-	if (unlikely(NInoNonResident(ni))) {
-		unmap_mft_record(base_ni);
-		goto retry_writepage;
-	}
-	ctx = ntfs_attr_get_search_ctx(base_ni, m);
-	if (unlikely(!ctx)) {
-		err = -ENOMEM;
-		goto err_out;
-	}
-	err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
-			CASE_SENSITIVE, 0, NULL, 0, ctx);
-	if (unlikely(err))
-		goto err_out;
-	/*
-	 * Keep the VM happy.  This must be done otherwise
-	 * PAGECACHE_TAG_DIRTY remains set even though the folio is clean.
-	 */
-	BUG_ON(folio_test_writeback(folio));
-	folio_start_writeback(folio);
-	folio_unlock(folio);
-	attr_len = le32_to_cpu(ctx->attr->data.resident.value_length);
-	i_size = i_size_read(vi);
-	if (unlikely(attr_len > i_size)) {
-		/* Race with shrinking truncate or a failed truncate. */
-		attr_len = i_size;
-		/*
-		 * If the truncate failed, fix it up now.  If a concurrent
-		 * truncate, we do its job, so it does not have to do anything.
-		 */
-		err = ntfs_resident_attr_value_resize(ctx->mrec, ctx->attr,
-				attr_len);
-		/* Shrinking cannot fail. */
-		BUG_ON(err);
-	}
-	addr = kmap_local_folio(folio, 0);
-	/* Copy the data from the folio to the mft record. */
-	memcpy((u8*)ctx->attr +
-			le16_to_cpu(ctx->attr->data.resident.value_offset),
-			addr, attr_len);
-	/* Zero out of bounds area in the page cache folio. */
-	memset(addr + attr_len, 0, folio_size(folio) - attr_len);
-	kunmap_local(addr);
-	flush_dcache_folio(folio);
-	flush_dcache_mft_record_page(ctx->ntfs_ino);
-	/* We are done with the folio. */
-	folio_end_writeback(folio);
-	/* Finally, mark the mft record dirty, so it gets written back. */
-	mark_mft_record_dirty(ctx->ntfs_ino);
-	ntfs_attr_put_search_ctx(ctx);
-	unmap_mft_record(base_ni);
-	return 0;
-err_out:
-	if (err == -ENOMEM) {
-		ntfs_warning(vi->i_sb, "Error allocating memory. Redirtying "
-				"page so we try again later.");
-		/*
-		 * Put the folio back on mapping->dirty_pages, but leave its
-		 * buffers' dirty state as-is.
-		 */
-		folio_redirty_for_writepage(wbc, folio);
-		err = 0;
-	} else {
-		ntfs_error(vi->i_sb, "Resident attribute write failed with "
-				"error %i.", err);
-		folio_set_error(folio);
-		NVolSetErrors(ni->vol);
-	}
-	folio_unlock(folio);
-	if (ctx)
-		ntfs_attr_put_search_ctx(ctx);
-	if (m)
-		unmap_mft_record(base_ni);
-	return err;
-}
-
-#endif	/* NTFS_RW */
-
 /**
  * ntfs_bmap - map logical file block to physical device block
  * @mapping:	address space mapping to which the block to be mapped belongs
@@ -1533,26 +281,24 @@ static sector_t ntfs_bmap(struct address_space *mapping, sector_t block)
 {
 	s64 ofs, size;
 	loff_t i_size;
-	LCN lcn;
+	s64 lcn;
 	unsigned long blocksize, flags;
-	ntfs_inode *ni = NTFS_I(mapping->host);
-	ntfs_volume *vol = ni->vol;
-	unsigned delta;
-	unsigned char blocksize_bits, cluster_size_shift;
+	struct ntfs_inode *ni = NTFS_I(mapping->host);
+	struct ntfs_volume *vol = ni->vol;
+	unsigned int delta;
+	unsigned char blocksize_bits;
 
 	ntfs_debug("Entering for mft_no 0x%lx, logical block 0x%llx.",
 			ni->mft_no, (unsigned long long)block);
-	if (ni->type != AT_DATA || !NInoNonResident(ni) || NInoEncrypted(ni)) {
-		ntfs_error(vol->sb, "BMAP does not make sense for %s "
-				"attributes, returning 0.",
+	if (ni->type != AT_DATA || !NInoNonResident(ni) || NInoEncrypted(ni) ||
+	    NInoMstProtected(ni)) {
+		ntfs_error(vol->sb, "BMAP does not make sense for %s attributes, returning 0.",
 				(ni->type != AT_DATA) ? "non-data" :
 				(!NInoNonResident(ni) ? "resident" :
 				"encrypted"));
 		return 0;
 	}
 	/* None of these can happen. */
-	BUG_ON(NInoCompressed(ni));
-	BUG_ON(NInoMstProtected(ni));
 	blocksize = vol->sb->s_blocksize;
 	blocksize_bits = vol->sb->s_blocksize_bits;
 	ofs = (s64)block << blocksize_bits;
@@ -1567,9 +313,8 @@ static sector_t ntfs_bmap(struct address_space *mapping, sector_t block)
 	 */
 	if (unlikely(ofs >= size || (ofs + blocksize > size && size < i_size)))
 		goto hole;
-	cluster_size_shift = vol->cluster_size_bits;
 	down_read(&ni->runlist.lock);
-	lcn = ntfs_attr_vcn_to_lcn_nolock(ni, ofs >> cluster_size_shift, false);
+	lcn = ntfs_attr_vcn_to_lcn_nolock(ni, NTFS_B_TO_CLU(vol, ofs), false);
 	up_read(&ni->runlist.lock);
 	if (unlikely(lcn < LCN_HOLE)) {
 		/*
@@ -1589,14 +334,14 @@ static sector_t ntfs_bmap(struct address_space *mapping, sector_t block)
 			 */
 			goto hole;
 		case LCN_ENOMEM:
-			ntfs_error(vol->sb, "Not enough memory to complete "
-					"mapping for inode 0x%lx.  "
-					"Returning 0.", ni->mft_no);
+			ntfs_error(vol->sb,
+				"Not enough memory to complete mapping for inode 0x%lx. Returning 0.",
+				ni->mft_no);
 			break;
 		default:
-			ntfs_error(vol->sb, "Failed to complete mapping for "
-					"inode 0x%lx.  Run chkdsk.  "
-					"Returning 0.", ni->mft_no);
+			ntfs_error(vol->sb,
+				"Failed to complete mapping for inode 0x%lx.  Run chkdsk. Returning 0.",
+				ni->mft_no);
 			break;
 		}
 		return 0;
@@ -1613,132 +358,186 @@ static sector_t ntfs_bmap(struct address_space *mapping, sector_t block)
 	 */
 	delta = ofs & vol->cluster_size_mask;
 	if (unlikely(sizeof(block) < sizeof(lcn))) {
-		block = lcn = ((lcn << cluster_size_shift) + delta) >>
+		block = lcn = (NTFS_CLU_TO_B(vol, lcn) + delta) >>
 				blocksize_bits;
 		/* If the block number was truncated return 0. */
 		if (unlikely(block != lcn)) {
-			ntfs_error(vol->sb, "Physical block 0x%llx is too "
-					"large to be returned, returning 0.",
-					(long long)lcn);
+			ntfs_error(vol->sb,
+				"Physical block 0x%llx is too large to be returned, returning 0.",
+				(long long)lcn);
 			return 0;
 		}
 	} else
-		block = ((lcn << cluster_size_shift) + delta) >>
+		block = (NTFS_CLU_TO_B(vol, lcn) + delta) >>
 				blocksize_bits;
 	ntfs_debug("Done (returning block 0x%llx).", (unsigned long long)lcn);
 	return block;
 }
 
-/*
- * ntfs_normal_aops - address space operations for normal inodes and attributes
- *
- * Note these are not used for compressed or mst protected inodes and
- * attributes.
- */
-const struct address_space_operations ntfs_normal_aops = {
-	.read_folio	= ntfs_read_folio,
-#ifdef NTFS_RW
-	.writepage	= ntfs_writepage,
-	.dirty_folio	= block_dirty_folio,
-#endif /* NTFS_RW */
-	.bmap		= ntfs_bmap,
-	.migrate_folio	= buffer_migrate_folio,
-	.is_partially_uptodate = block_is_partially_uptodate,
-	.error_remove_folio = generic_error_remove_folio,
-};
+static void ntfs_readahead(struct readahead_control *rac)
+{
+	struct address_space *mapping = rac->mapping;
+	struct inode *inode = mapping->host;
+	struct ntfs_inode *ni = NTFS_I(inode);
 
-/*
- * ntfs_compressed_aops - address space operations for compressed inodes
- */
-const struct address_space_operations ntfs_compressed_aops = {
-	.read_folio	= ntfs_read_folio,
-#ifdef NTFS_RW
-	.writepage	= ntfs_writepage,
-	.dirty_folio	= block_dirty_folio,
-#endif /* NTFS_RW */
-	.migrate_folio	= buffer_migrate_folio,
-	.is_partially_uptodate = block_is_partially_uptodate,
-	.error_remove_folio = generic_error_remove_folio,
-};
+	if (!NInoNonResident(ni) || NInoCompressed(ni)) {
+		/* No readahead for resident and compressed. */
+		return;
+	}
 
-/*
- * ntfs_mst_aops - general address space operations for mst protecteed inodes
- *			  and attributes
- */
-const struct address_space_operations ntfs_mst_aops = {
-	.read_folio	= ntfs_read_folio,	/* Fill page with data. */
-#ifdef NTFS_RW
-	.writepage	= ntfs_writepage,	/* Write dirty page to disk. */
-	.dirty_folio	= filemap_dirty_folio,
-#endif /* NTFS_RW */
-	.migrate_folio	= buffer_migrate_folio,
-	.is_partially_uptodate	= block_is_partially_uptodate,
-	.error_remove_folio = generic_error_remove_folio,
-};
+	iomap_bio_readahead(rac, &ntfs_read_iomap_ops);
+}
 
-#ifdef NTFS_RW
+static int ntfs_mft_writepage(struct folio *folio, struct writeback_control *wbc)
+{
+	struct address_space *mapping = folio->mapping;
+	struct inode *vi = mapping->host;
+	struct ntfs_inode *ni = NTFS_I(vi);
+	loff_t i_size;
+	int ret;
 
-/**
- * mark_ntfs_record_dirty - mark an ntfs record dirty
- * @page:	page containing the ntfs record to mark dirty
- * @ofs:	byte offset within @page at which the ntfs record begins
- *
- * Set the buffers and the page in which the ntfs record is located dirty.
- *
- * The latter also marks the vfs inode the ntfs record belongs to dirty
- * (I_DIRTY_PAGES only).
- *
- * If the page does not have buffers, we create them and set them uptodate.
- * The page may not be locked which is why we need to handle the buffers under
- * the mapping->i_private_lock.  Once the buffers are marked dirty we no longer
- * need the lock since try_to_free_buffers() does not free dirty buffers.
- */
-void mark_ntfs_record_dirty(struct page *page, const unsigned int ofs) {
-	struct address_space *mapping = page->mapping;
-	ntfs_inode *ni = NTFS_I(mapping->host);
-	struct buffer_head *bh, *head, *buffers_to_free = NULL;
-	unsigned int end, bh_size, bh_ofs;
-
-	BUG_ON(!PageUptodate(page));
-	end = ofs + ni->itype.index.block_size;
-	bh_size = VFS_I(ni)->i_sb->s_blocksize;
-	spin_lock(&mapping->i_private_lock);
-	if (unlikely(!page_has_buffers(page))) {
-		spin_unlock(&mapping->i_private_lock);
-		bh = head = alloc_page_buffers(page, bh_size, true);
-		spin_lock(&mapping->i_private_lock);
-		if (likely(!page_has_buffers(page))) {
-			struct buffer_head *tail;
-
-			do {
-				set_buffer_uptodate(bh);
-				tail = bh;
-				bh = bh->b_this_page;
-			} while (bh);
-			tail->b_this_page = head;
-			attach_page_private(page, head);
-		} else
-			buffers_to_free = bh;
+	i_size = i_size_read(vi);
+
+	/* We have to zero every time due to mmap-at-end-of-file. */
+	if (folio->index >= (i_size >> PAGE_SHIFT)) {
+		/* The page straddles i_size. */
+		unsigned int ofs = i_size & ~PAGE_MASK;
+
+		folio_zero_segment(folio, ofs, PAGE_SIZE);
 	}
-	bh = head = page_buffers(page);
-	BUG_ON(!bh);
-	do {
-		bh_ofs = bh_offset(bh);
-		if (bh_ofs + bh_size <= ofs)
-			continue;
-		if (unlikely(bh_ofs >= end))
-			break;
-		set_buffer_dirty(bh);
-	} while ((bh = bh->b_this_page) != head);
-	spin_unlock(&mapping->i_private_lock);
-	filemap_dirty_folio(mapping, page_folio(page));
-	if (unlikely(buffers_to_free)) {
-		do {
-			bh = buffers_to_free->b_this_page;
-			free_buffer_head(buffers_to_free);
-			buffers_to_free = bh;
-		} while (buffers_to_free);
+
+	ret = ntfs_write_mft_block(ni, folio, wbc);
+	mapping_set_error(mapping, ret);
+	return ret;
+}
+
+static int ntfs_writepages(struct address_space *mapping,
+		struct writeback_control *wbc)
+{
+	struct inode *inode = mapping->host;
+	struct ntfs_inode *ni = NTFS_I(inode);
+	struct iomap_writepage_ctx wpc = {
+		.inode		= mapping->host,
+		.wbc		= wbc,
+		.ops		= &ntfs_writeback_ops,
+	};
+
+	if (NVolShutdown(ni->vol))
+		return -EIO;
+
+	if (!NInoNonResident(ni))
+		return 0;
+
+	if (NInoMstProtected(ni) && ni->mft_no == FILE_MFT) {
+		struct folio *folio = NULL;
+		int error;
+
+		while ((folio = writeback_iter(mapping, wbc, folio, &error)))
+			error = ntfs_mft_writepage(folio, wbc);
+		return error;
+	}
+
+	/* If file is encrypted, deny access, just like NT4. */
+	if (NInoEncrypted(ni)) {
+		ntfs_debug("Denying write access to encrypted file.");
+		return -EACCES;
+	}
+
+	return iomap_writepages(&wpc);
+}
+
+static int ntfs_swap_activate(struct swap_info_struct *sis,
+		struct file *swap_file, sector_t *span)
+{
+	return iomap_swapfile_activate(sis, swap_file, span,
+			&ntfs_read_iomap_ops);
+}
+
+const struct address_space_operations ntfs_aops = {
+	.read_folio		= ntfs_read_folio,
+	.readahead		= ntfs_readahead,
+	.writepages		= ntfs_writepages,
+	.direct_IO		= noop_direct_IO,
+	.dirty_folio		= iomap_dirty_folio,
+	.bmap			= ntfs_bmap,
+	.migrate_folio		= filemap_migrate_folio,
+	.is_partially_uptodate	= iomap_is_partially_uptodate,
+	.error_remove_folio	= generic_error_remove_folio,
+	.release_folio		= iomap_release_folio,
+	.invalidate_folio	= iomap_invalidate_folio,
+	.swap_activate          = ntfs_swap_activate,
+};
+
+void mark_ntfs_record_dirty(struct folio *folio)
+{
+	iomap_dirty_folio(folio->mapping, folio);
+}
+
+int ntfs_dev_read(struct super_block *sb, void *buf, loff_t start, loff_t size)
+{
+	pgoff_t idx, idx_end;
+	loff_t offset, end = start + size;
+	u32 from, to, buf_off = 0;
+	struct folio *folio;
+
+	idx = start >> PAGE_SHIFT;
+	idx_end = end >> PAGE_SHIFT;
+	from = start & ~PAGE_MASK;
+
+	if (idx == idx_end)
+		idx_end++;
+
+	for (; idx < idx_end; idx++, from = 0) {
+		folio = read_mapping_folio(sb->s_bdev->bd_mapping, idx, NULL);
+		if (IS_ERR(folio)) {
+			ntfs_error(sb, "Unable to read %ld page", idx);
+			return PTR_ERR(folio);
+		}
+
+		offset = (loff_t)idx << PAGE_SHIFT;
+		to = min_t(u32, end - offset, PAGE_SIZE);
+
+		memcpy_from_folio(buf + buf_off, folio, from, to);
+		buf_off += to;
+		folio_put(folio);
 	}
+
+	return 0;
 }
 
-#endif /* NTFS_RW */
+int ntfs_dev_write(struct super_block *sb, void *buf, loff_t start,
+			loff_t size, bool wait)
+{
+	pgoff_t idx, idx_end;
+	loff_t offset, end = start + size;
+	u32 from, to, buf_off = 0;
+	struct folio *folio;
+
+	idx = start >> PAGE_SHIFT;
+	idx_end = end >> PAGE_SHIFT;
+	from = start & ~PAGE_MASK;
+
+	if (idx == idx_end)
+		idx_end++;
+
+	for (; idx < idx_end; idx++, from = 0) {
+		folio = read_mapping_folio(sb->s_bdev->bd_mapping, idx, NULL);
+		if (IS_ERR(folio)) {
+			ntfs_error(sb, "Unable to read %ld page", idx);
+			return PTR_ERR(folio);
+		}
+
+		offset = (loff_t)idx << PAGE_SHIFT;
+		to = min_t(u32, end - offset, PAGE_SIZE);
+
+		memcpy_to_folio(folio, from, buf + buf_off, to);
+		buf_off += to;
+		folio_mark_uptodate(folio);
+		folio_mark_dirty(folio);
+		if (wait)
+			folio_wait_stable(folio);
+		folio_put(folio);
+	}
+
+	return 0;
+}
diff --git a/fs/ntfs/iomap.c b/fs/ntfs/iomap.c
new file mode 100644
index 000000000000..797bfd21ce77
--- /dev/null
+++ b/fs/ntfs/iomap.c
@@ -0,0 +1,753 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/**
+ * iomap callack functions
+ *
+ * Copyright (c) 2025 LG Electronics Co., Ltd.
+ */
+
+#include <linux/writeback.h>
+#include <linux/mpage.h>
+#include <linux/uio.h>
+
+#include "aops.h"
+#include "attrib.h"
+#include "mft.h"
+#include "ntfs.h"
+#include "malloc.h"
+#include "iomap.h"
+
+/*
+ * ioomap_zero_range is called for an area beyond the initialized size,
+ * garbage values can be read, so zeroing out is needed.
+ */
+static void ntfs_iomap_put_folio(struct inode *inode, loff_t pos,
+		unsigned int len, struct folio *folio)
+{
+	struct ntfs_inode *ni = NTFS_I(inode);
+	unsigned long sector_size = 1UL << inode->i_blkbits;
+	loff_t start_down, end_up, init;
+
+	if (!NInoNonResident(ni))
+		goto out;
+
+	start_down = round_down(pos, sector_size);
+	end_up = (pos + len - 1) | (sector_size - 1);
+	init = ni->initialized_size;
+
+	if (init >= start_down && init <= end_up) {
+		if (init < pos) {
+			loff_t offset = offset_in_folio(folio, pos + len);
+
+			if (offset == 0)
+				offset = folio_size(folio);
+			folio_zero_segments(folio,
+					    offset_in_folio(folio, init),
+					    offset_in_folio(folio, pos),
+					    offset,
+					    folio_size(folio));
+
+		} else  {
+			loff_t offset = max_t(loff_t, pos + len, init);
+
+			offset = offset_in_folio(folio, offset);
+			if (offset == 0)
+				offset = folio_size(folio);
+			folio_zero_segment(folio,
+					   offset,
+					   folio_size(folio));
+		}
+	} else if (init <= pos) {
+		loff_t offset = 0, offset2 = offset_in_folio(folio, pos + len);
+
+		if ((init >> folio_shift(folio)) == (pos >> folio_shift(folio)))
+			offset = offset_in_folio(folio, init);
+		if (offset2 == 0)
+			offset2 = folio_size(folio);
+		folio_zero_segments(folio,
+				    offset,
+				    offset_in_folio(folio, pos),
+				    offset2,
+				    folio_size(folio));
+	}
+
+out:
+	folio_unlock(folio);
+	folio_put(folio);
+}
+
+const struct iomap_write_ops ntfs_iomap_folio_ops = {
+	.put_folio = ntfs_iomap_put_folio,
+};
+
+static int ntfs_read_iomap_begin_resident(struct inode *inode, loff_t offset,
+		unsigned int flags, struct iomap *iomap)
+{
+	struct ntfs_inode *base_ni, *ni = NTFS_I(inode);
+	struct ntfs_attr_search_ctx *ctx;
+	loff_t i_size;
+	u32 attr_len;
+	int err = 0;
+	char *kattr;
+
+	if (NInoAttr(ni))
+		base_ni = ni->ext.base_ntfs_ino;
+	else
+		base_ni = ni;
+
+	ctx = ntfs_attr_get_search_ctx(base_ni, NULL);
+	if (!ctx) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
+			CASE_SENSITIVE, 0, NULL, 0, ctx);
+	if (unlikely(err))
+		goto out;
+
+	attr_len = le32_to_cpu(ctx->attr->data.resident.value_length);
+	if (unlikely(attr_len > ni->initialized_size))
+		attr_len = ni->initialized_size;
+	i_size = i_size_read(inode);
+
+	if (unlikely(attr_len > i_size)) {
+		/* Race with shrinking truncate. */
+		attr_len = i_size;
+	}
+
+	if (offset >= attr_len) {
+		if (flags & IOMAP_REPORT)
+			err = -ENOENT;
+		else
+			err = -EFAULT;
+		goto out;
+	}
+
+	kattr = (u8 *)ctx->attr + le16_to_cpu(ctx->attr->data.resident.value_offset);
+
+	iomap->inline_data = kmemdup(kattr, attr_len, GFP_KERNEL);
+	if (!iomap->inline_data) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	iomap->type = IOMAP_INLINE;
+	iomap->offset = 0;
+	iomap->length = min_t(loff_t, attr_len, PAGE_SIZE);
+
+out:
+	if (ctx)
+		ntfs_attr_put_search_ctx(ctx);
+
+	return err;
+}
+
+static int ntfs_read_iomap_begin_non_resident(struct inode *inode, loff_t offset,
+		loff_t length, unsigned int flags, struct iomap *iomap)
+{
+	struct ntfs_inode *ni = NTFS_I(inode);
+	s64 vcn;
+	s64 lcn;
+	struct runlist_element *rl;
+	struct ntfs_volume *vol = ni->vol;
+	loff_t vcn_ofs;
+	loff_t rl_length;
+
+	vcn = NTFS_B_TO_CLU(vol, offset);
+	vcn_ofs = NTFS_B_TO_CLU_OFS(vol, offset);
+
+	down_write(&ni->runlist.lock);
+	rl = ntfs_attr_vcn_to_rl(ni, vcn, &lcn);
+	if (IS_ERR(rl)) {
+		up_write(&ni->runlist.lock);
+		return PTR_ERR(rl);
+	}
+
+	if (flags & IOMAP_REPORT) {
+		if (lcn < LCN_HOLE) {
+			up_write(&ni->runlist.lock);
+			return -ENOENT;
+		}
+	} else if (lcn < LCN_ENOENT) {
+		up_write(&ni->runlist.lock);
+		return -EINVAL;
+	}
+
+	iomap->bdev = inode->i_sb->s_bdev;
+	iomap->offset = offset;
+
+	if (lcn <= LCN_DELALLOC) {
+		if (lcn == LCN_DELALLOC)
+			iomap->type = IOMAP_DELALLOC;
+		else
+			iomap->type = IOMAP_HOLE;
+		iomap->addr = IOMAP_NULL_ADDR;
+	} else {
+		if (!(flags & IOMAP_ZERO) && offset >= ni->initialized_size)
+			iomap->type = IOMAP_UNWRITTEN;
+		else
+			iomap->type = IOMAP_MAPPED;
+		iomap->addr = NTFS_CLU_TO_B(vol, lcn) + vcn_ofs;
+	}
+
+	rl_length = NTFS_CLU_TO_B(vol, rl->length - (vcn - rl->vcn));
+
+	if (rl_length == 0 && rl->lcn > LCN_DELALLOC) {
+		ntfs_error(inode->i_sb,
+				"runlist(vcn : %lld, length : %lld, lcn : %lld) is corrupted\n",
+				rl->vcn, rl->length, rl->lcn);
+		up_write(&ni->runlist.lock);
+		return -EIO;
+	}
+
+	if (rl_length && length > rl_length - vcn_ofs)
+		iomap->length = rl_length - vcn_ofs;
+	else
+		iomap->length = length;
+	up_write(&ni->runlist.lock);
+
+	if (!(flags & IOMAP_ZERO) &&
+			iomap->type == IOMAP_MAPPED &&
+			iomap->offset < ni->initialized_size &&
+			iomap->offset + iomap->length > ni->initialized_size) {
+		iomap->length = round_up(ni->initialized_size, 1 << inode->i_blkbits) -
+			iomap->offset;
+	}
+	iomap->flags |= IOMAP_F_MERGED;
+
+	return 0;
+}
+
+static int ntfs_read_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
+		unsigned int flags, struct iomap *iomap, struct iomap *srcmap)
+{
+	struct ntfs_inode *ni = NTFS_I(inode);
+	int ret;
+
+	if (NInoNonResident(ni))
+		ret = ntfs_read_iomap_begin_non_resident(inode, offset, length,
+				flags, iomap);
+	else
+		ret = ntfs_read_iomap_begin_resident(inode, offset, flags, iomap);
+
+	return ret;
+}
+
+static int ntfs_read_iomap_end(struct inode *inode, loff_t pos, loff_t length,
+		ssize_t written, unsigned int flags, struct iomap *iomap)
+{
+	if (iomap->type == IOMAP_INLINE)
+		kfree(iomap->inline_data);
+
+	return written;
+}
+
+const struct iomap_ops ntfs_read_iomap_ops = {
+	.iomap_begin = ntfs_read_iomap_begin,
+	.iomap_end = ntfs_read_iomap_end,
+};
+
+/*
+ * Check that the cached iomap still matches the NTFS runlist before
+ * iomap_zero_range() is called. if the runlist changes while iomap is
+ * iterating a cached iomap, iomap_zero_range() may overwrite folios
+ * that have been already written with valid data.
+ */
+static bool ntfs_iomap_valid(struct inode *inode, const struct iomap *iomap)
+{
+	struct ntfs_inode *ni = NTFS_I(inode);
+	struct runlist_element *rl;
+	s64 vcn, lcn;
+
+	if (!NInoNonResident(ni))
+		return false;
+
+	vcn = iomap->offset >> ni->vol->cluster_size_bits;
+
+	down_read(&ni->runlist.lock);
+	rl = __ntfs_attr_find_vcn_nolock(&ni->runlist, vcn);
+	if (IS_ERR(rl)) {
+		up_read(&ni->runlist.lock);
+		return false;
+	}
+	lcn = ntfs_rl_vcn_to_lcn(rl, vcn);
+	up_read(&ni->runlist.lock);
+	return lcn == LCN_DELALLOC;
+}
+
+const struct iomap_write_ops ntfs_zero_iomap_folio_ops = {
+	.put_folio = ntfs_iomap_put_folio,
+	.iomap_valid = ntfs_iomap_valid,
+};
+
+static int ntfs_zero_read_iomap_end(struct inode *inode, loff_t pos, loff_t length,
+		ssize_t written, unsigned int flags, struct iomap *iomap)
+{
+	if ((flags & IOMAP_ZERO) && (iomap->flags & IOMAP_F_STALE))
+		return -EPERM;
+	return written;
+}
+
+const struct iomap_ops ntfs_zero_read_iomap_ops = {
+	.iomap_begin = ntfs_read_iomap_begin,
+	.iomap_end = ntfs_zero_read_iomap_end,
+};
+
+int ntfs_zero_range(struct inode *inode, loff_t offset, loff_t length, bool bdirect)
+{
+	if (bdirect) {
+		if ((offset | length) & (SECTOR_SIZE - 1))
+			return -EINVAL;
+
+		return  blkdev_issue_zeroout(inode->i_sb->s_bdev,
+					     offset >> SECTOR_SHIFT,
+					     length >> SECTOR_SHIFT,
+					     GFP_NOFS,
+					     BLKDEV_ZERO_NOUNMAP);
+	}
+
+	return iomap_zero_range(inode,
+				offset, length,
+				NULL,
+				&ntfs_zero_read_iomap_ops,
+				&ntfs_zero_iomap_folio_ops,
+				NULL);
+}
+
+static int ntfs_write_iomap_begin_non_resident(struct inode *inode, loff_t offset,
+		loff_t length, struct iomap *iomap)
+{
+	struct ntfs_inode *ni = NTFS_I(inode);
+	struct ntfs_volume *vol = ni->vol;
+	loff_t vcn_ofs, rl_length;
+	struct runlist_element *rl, *rlc;
+	bool is_retry = false;
+	int err;
+	s64 vcn, lcn;
+	s64 max_clu_count =
+		NTFS_B_TO_CLU(vol, round_up(length, vol->cluster_size));
+
+	vcn = NTFS_B_TO_CLU(vol, offset);
+	vcn_ofs = NTFS_B_TO_CLU_OFS(vol, offset);
+
+	down_read(&ni->runlist.lock);
+	rl = ni->runlist.rl;
+	if (!rl) {
+		up_read(&ni->runlist.lock);
+		err = ntfs_map_runlist(ni, vcn);
+		if (err) {
+			mutex_unlock(&ni->mrec_lock);
+			return -ENOENT;
+		}
+		down_read(&ni->runlist.lock);
+		rl = ni->runlist.rl;
+	}
+	up_read(&ni->runlist.lock);
+
+	down_write(&ni->runlist.lock);
+remap_rl:
+	/* Seek to element containing target vcn. */
+	rl = __ntfs_attr_find_vcn_nolock(&ni->runlist, vcn);
+	if (IS_ERR(rl)) {
+		up_write(&ni->runlist.lock);
+		return false;
+	}
+	lcn = ntfs_rl_vcn_to_lcn(rl, vcn);
+
+	if (lcn <= LCN_RL_NOT_MAPPED && is_retry == false) {
+		is_retry = true;
+		if (!ntfs_map_runlist_nolock(ni, vcn, NULL)) {
+			rl = ni->runlist.rl;
+			goto remap_rl;
+		}
+	}
+
+	max_clu_count = min(max_clu_count, rl->length - (vcn - rl->vcn));
+	if (max_clu_count == 0) {
+		ntfs_error(inode->i_sb,
+				"runlist(vcn : %lld, length : %lld) is corrupted\n",
+				rl->vcn, rl->length);
+		up_write(&ni->runlist.lock);
+		mutex_unlock(&ni->mrec_lock);
+		return -EIO;
+	}
+
+	iomap->bdev = inode->i_sb->s_bdev;
+	iomap->offset = offset;
+
+	if (lcn <= LCN_DELALLOC) {
+		if (lcn < LCN_DELALLOC) {
+			max_clu_count =
+				ntfs_available_clusters_count(vol, max_clu_count);
+			if (max_clu_count < 0) {
+				err = max_clu_count;
+				up_write(&ni->runlist.lock);
+				mutex_unlock(&ni->mrec_lock);
+				return err;
+			}
+		}
+
+		iomap->type = IOMAP_DELALLOC;
+		iomap->addr = IOMAP_NULL_ADDR;
+
+		if (lcn <= LCN_HOLE) {
+			size_t new_rl_count;
+
+			rlc = ntfs_malloc_nofs(sizeof(struct runlist_element) * 2);
+			if (!rlc) {
+				up_write(&ni->runlist.lock);
+				mutex_unlock(&ni->mrec_lock);
+				return -ENOMEM;
+			}
+
+			rlc->vcn = vcn;
+			rlc->lcn = LCN_DELALLOC;
+			rlc->length = max_clu_count;
+
+			rlc[1].vcn = vcn + max_clu_count;
+			rlc[1].lcn = LCN_RL_NOT_MAPPED;
+			rlc[1].length = 0;
+
+			rl = ntfs_runlists_merge(&ni->runlist, rlc, 0,
+					&new_rl_count);
+			if (IS_ERR(rl)) {
+				ntfs_error(vol->sb, "Failed to merge runlists");
+				up_write(&ni->runlist.lock);
+				mutex_unlock(&ni->mrec_lock);
+				ntfs_free(rlc);
+				return PTR_ERR(rl);
+			}
+
+			ni->runlist.rl = rl;
+			ni->runlist.count = new_rl_count;
+			ni->i_dealloc_clusters += max_clu_count;
+		}
+		up_write(&ni->runlist.lock);
+		mutex_unlock(&ni->mrec_lock);
+
+		if (lcn < LCN_DELALLOC)
+			ntfs_hold_dirty_clusters(vol, max_clu_count);
+
+		rl_length = NTFS_CLU_TO_B(vol, max_clu_count);
+		if (length > rl_length - vcn_ofs)
+			iomap->length = rl_length - vcn_ofs;
+		else
+			iomap->length = length;
+
+		iomap->flags = IOMAP_F_NEW;
+		if (lcn <= LCN_HOLE) {
+			loff_t end = offset + length;
+
+			if (vcn_ofs || ((vol->cluster_size > iomap->length) &&
+					end < ni->initialized_size)) {
+				loff_t z_start, z_end;
+
+				z_start = vcn << vol->cluster_size_bits;
+				z_end = min_t(loff_t, z_start + vol->cluster_size,
+					      i_size_read(inode));
+				if (z_end > z_start)
+					err = ntfs_zero_range(inode,
+							      z_start,
+							      z_end - z_start,
+							      false);
+			}
+			if ((!err || err == -EPERM) &&
+			    max_clu_count > 1 &&
+			    (iomap->length & vol->cluster_size_mask &&
+			     end < ni->initialized_size)) {
+				loff_t z_start, z_end;
+
+				z_start = (vcn + max_clu_count - 1) <<
+					vol->cluster_size_bits;
+				z_end = min_t(loff_t, z_start + vol->cluster_size,
+					      i_size_read(inode));
+				if (z_end > z_start)
+					err = ntfs_zero_range(inode,
+							      z_start,
+							      z_end - z_start,
+							      false);
+			}
+
+			if (err == -EPERM)
+				err = 0;
+			if (err) {
+				ntfs_release_dirty_clusters(vol, max_clu_count);
+				return err;
+			}
+		}
+	} else {
+		up_write(&ni->runlist.lock);
+		mutex_unlock(&ni->mrec_lock);
+
+		iomap->type = IOMAP_MAPPED;
+		iomap->addr = NTFS_CLU_TO_B(vol, lcn) + vcn_ofs;
+
+		rl_length = NTFS_CLU_TO_B(vol, max_clu_count);
+		if (length > rl_length - vcn_ofs)
+			iomap->length = rl_length - vcn_ofs;
+		else
+			iomap->length = length;
+	}
+
+	return 0;
+}
+
+static int ntfs_write_da_iomap_begin_non_resident(struct inode *inode, loff_t offset,
+		loff_t length, unsigned int flags, struct iomap *iomap, bool mapped)
+{
+	struct ntfs_inode *ni = NTFS_I(inode);
+	struct ntfs_volume *vol = ni->vol;
+	loff_t vcn_ofs, rl_length;
+	s64 vcn, start_lcn, lcn_count;
+	bool balloc = false, update_mp;
+	int err;
+	s64 max_clu_count =
+		NTFS_B_TO_CLU(vol, round_up(length, vol->cluster_size));
+
+	vcn = NTFS_B_TO_CLU(vol, offset);
+	vcn_ofs = NTFS_B_TO_CLU_OFS(vol, offset);
+
+	update_mp = (flags & IOMAP_DIRECT) || mapped ||
+		NInoAttr(ni) || ni->mft_no < FILE_first_user;
+	down_write(&ni->runlist.lock);
+	err = ntfs_attr_map_cluster(ni, vcn, &start_lcn, &lcn_count,
+			max_clu_count, &balloc, update_mp,
+			!(flags & IOMAP_DIRECT) && !mapped);
+	up_write(&ni->runlist.lock);
+	mutex_unlock(&ni->mrec_lock);
+	if (err) {
+		ni->i_dealloc_clusters = 0;
+		return err;
+	}
+
+	iomap->bdev = inode->i_sb->s_bdev;
+	iomap->offset = offset;
+
+	rl_length = NTFS_CLU_TO_B(vol, lcn_count);
+	if (length > rl_length - vcn_ofs)
+		iomap->length = rl_length - vcn_ofs;
+	else
+		iomap->length = length;
+
+	if (start_lcn == LCN_HOLE)
+		iomap->type = IOMAP_HOLE;
+	else
+		iomap->type = IOMAP_MAPPED;
+	if (balloc == true)
+		iomap->flags = IOMAP_F_NEW;
+
+	iomap->addr = NTFS_CLU_TO_B(vol, start_lcn) + vcn_ofs;
+
+	if (balloc == true) {
+		if (flags & IOMAP_DIRECT || mapped == true) {
+			loff_t end = offset + length;
+
+			if (vcn_ofs || ((vol->cluster_size > iomap->length) &&
+						end < ni->initialized_size))
+				err = ntfs_zero_range(inode,
+						      start_lcn <<
+						      vol->cluster_size_bits,
+						      vol->cluster_size,
+						      true);
+			if (!err && lcn_count > 1 &&
+					(iomap->length & vol->cluster_size_mask &&
+					 end < ni->initialized_size))
+				err = ntfs_zero_range(inode,
+						      (start_lcn + lcn_count - 1) <<
+						      vol->cluster_size_bits,
+						      vol->cluster_size,
+						      true);
+		} else {
+			if (lcn_count > ni->i_dealloc_clusters)
+				ni->i_dealloc_clusters = 0;
+			else
+				ni->i_dealloc_clusters -= lcn_count;
+		}
+		if (err < 0)
+			return err;
+	}
+
+	if (mapped && iomap->offset + iomap->length >
+			ni->initialized_size) {
+		err = ntfs_attr_set_initialized_size(ni, iomap->offset +
+				iomap->length);
+	}
+
+	return err;
+}
+
+static int ntfs_write_iomap_begin_resident(struct inode *inode, loff_t offset,
+		struct iomap *iomap)
+{
+	struct ntfs_inode *ni = NTFS_I(inode);
+	struct attr_record *a;
+	struct ntfs_attr_search_ctx *ctx;
+	u32 attr_len;
+	int err = 0;
+	char *kattr;
+
+	ctx = ntfs_attr_get_search_ctx(ni, NULL);
+	if (!ctx) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
+			CASE_SENSITIVE, 0, NULL, 0, ctx);
+	if (err) {
+		if (err == -ENOENT)
+			err = -EIO;
+		goto out;
+	}
+
+	a = ctx->attr;
+	/* The total length of the attribute value. */
+	attr_len = le32_to_cpu(a->data.resident.value_length);
+	kattr = (u8 *)a + le16_to_cpu(a->data.resident.value_offset);
+
+	iomap->inline_data = kmemdup(kattr, attr_len, GFP_KERNEL);
+	if (!iomap->inline_data) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	iomap->type = IOMAP_INLINE;
+	iomap->offset = 0;
+	/* iomap requires there is only one INLINE_DATA extent */
+	iomap->length = attr_len;
+
+out:
+	if (ctx)
+		ntfs_attr_put_search_ctx(ctx);
+	mutex_unlock(&ni->mrec_lock);
+	return err;
+}
+
+static int __ntfs_write_iomap_begin(struct inode *inode, loff_t offset,
+				    loff_t length, unsigned int flags,
+				    struct iomap *iomap, bool da, bool mapped)
+{
+	struct ntfs_inode *ni = NTFS_I(inode);
+	int ret;
+
+	if (NVolShutdown(ni->vol))
+		return -EIO;
+
+	mutex_lock(&ni->mrec_lock);
+	if (NInoNonResident(ni)) {
+		if (da)
+			ret = ntfs_write_da_iomap_begin_non_resident(inode,
+					offset, length, flags, iomap, mapped);
+		else
+			ret = ntfs_write_iomap_begin_non_resident(inode, offset,
+					length, iomap);
+	} else
+		ret = ntfs_write_iomap_begin_resident(inode, offset, iomap);
+	return ret;
+}
+
+static int ntfs_write_iomap_begin(struct inode *inode, loff_t offset,
+				  loff_t length, unsigned int flags,
+				  struct iomap *iomap, struct iomap *srcmap)
+{
+	return __ntfs_write_iomap_begin(inode, offset, length, flags, iomap,
+			false, false);
+}
+
+static int ntfs_write_iomap_end(struct inode *inode, loff_t pos, loff_t length,
+		ssize_t written, unsigned int flags, struct iomap *iomap)
+{
+	if (iomap->type == IOMAP_INLINE) {
+		struct ntfs_inode *ni = NTFS_I(inode);
+		struct ntfs_attr_search_ctx *ctx;
+		u32 attr_len;
+		int err;
+		char *kattr;
+
+		mutex_lock(&ni->mrec_lock);
+		ctx = ntfs_attr_get_search_ctx(ni, NULL);
+		if (!ctx) {
+			written = -ENOMEM;
+			mutex_unlock(&ni->mrec_lock);
+			goto out;
+		}
+
+		err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
+				CASE_SENSITIVE, 0, NULL, 0, ctx);
+		if (err) {
+			if (err == -ENOENT)
+				err = -EIO;
+			written = err;
+			goto err_out;
+		}
+
+		/* The total length of the attribute value. */
+		attr_len = le32_to_cpu(ctx->attr->data.resident.value_length);
+		if (pos >= attr_len || pos + written > attr_len)
+			goto err_out;
+
+		kattr = (u8 *)ctx->attr + le16_to_cpu(ctx->attr->data.resident.value_offset);
+		memcpy(kattr + pos, iomap_inline_data(iomap, pos), written);
+		mark_mft_record_dirty(ctx->ntfs_ino);
+err_out:
+		ntfs_attr_put_search_ctx(ctx);
+		kfree(iomap->inline_data);
+		mutex_unlock(&ni->mrec_lock);
+	}
+
+out:
+	return written;
+}
+
+const struct iomap_ops ntfs_write_iomap_ops = {
+	.iomap_begin		= ntfs_write_iomap_begin,
+	.iomap_end		= ntfs_write_iomap_end,
+};
+
+static int ntfs_page_mkwrite_iomap_begin(struct inode *inode, loff_t offset,
+				  loff_t length, unsigned int flags,
+				  struct iomap *iomap, struct iomap *srcmap)
+{
+	return __ntfs_write_iomap_begin(inode, offset, length, flags, iomap,
+			true, true);
+}
+
+const struct iomap_ops ntfs_page_mkwrite_iomap_ops = {
+	.iomap_begin		= ntfs_page_mkwrite_iomap_begin,
+	.iomap_end		= ntfs_write_iomap_end,
+};
+
+static int ntfs_dio_iomap_begin(struct inode *inode, loff_t offset,
+				  loff_t length, unsigned int flags,
+				  struct iomap *iomap, struct iomap *srcmap)
+{
+	return __ntfs_write_iomap_begin(inode, offset, length, flags, iomap,
+			true, false);
+}
+
+const struct iomap_ops ntfs_dio_iomap_ops = {
+	.iomap_begin		= ntfs_dio_iomap_begin,
+	.iomap_end		= ntfs_write_iomap_end,
+};
+
+static ssize_t ntfs_writeback_range(struct iomap_writepage_ctx *wpc,
+		struct folio *folio, u64 offset, unsigned int len, u64 end_pos)
+{
+	if (offset < wpc->iomap.offset ||
+	    offset >= wpc->iomap.offset + wpc->iomap.length) {
+		int error;
+
+		error = __ntfs_write_iomap_begin(wpc->inode, offset,
+				NTFS_I(wpc->inode)->allocated_size - offset,
+				IOMAP_WRITE, &wpc->iomap, true, false);
+		if (error)
+			return error;
+	}
+
+	return iomap_add_to_ioend(wpc, folio, offset, end_pos, len);
+}
+
+const struct iomap_writeback_ops ntfs_writeback_ops = {
+	.writeback_range	= ntfs_writeback_range,
+	.writeback_submit	= iomap_ioend_writeback_submit,
+};
-- 
2.25.1

Powered by blists - more mailing lists