1 files changed, 198 insertions, 135 deletions

diff --git a/fs/buffer.c b/fs/buffer.c
index a7fc561758b1..bd091329026c 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -111,7 +111,6 @@ void buffer_check_dirty_writeback(struct folio *folio,
 		bh = bh->b_this_page;
 	} while (bh != head);
 }
-EXPORT_SYMBOL(buffer_check_dirty_writeback);
 
 /*
  * Block until a buffer comes unlocked.  This doesn't stop it
@@ -195,19 +194,19 @@ __find_get_block_slow(struct block_device *bdev, sector_t block)
 	pgoff_t index;
 	struct buffer_head *bh;
 	struct buffer_head *head;
-	struct page *page;
+	struct folio *folio;
 	int all_mapped = 1;
 	static DEFINE_RATELIMIT_STATE(last_warned, HZ, 1);
 
 	index = block >> (PAGE_SHIFT - bd_inode->i_blkbits);
-	page = find_get_page_flags(bd_mapping, index, FGP_ACCESSED);
-	if (!page)
+	folio = __filemap_get_folio(bd_mapping, index, FGP_ACCESSED, 0);
+	if (IS_ERR(folio))
 		goto out;
 
 	spin_lock(&bd_mapping->private_lock);
-	if (!page_has_buffers(page))
+	head = folio_buffers(folio);
+	if (!head)
 		goto out_unlock;
-	head = page_buffers(page);
 	bh = head;
 	do {
 		if (!buffer_mapped(bh))
@@ -237,7 +236,7 @@ __find_get_block_slow(struct block_device *bdev, sector_t block)
 	}
 out_unlock:
 	spin_unlock(&bd_mapping->private_lock);
-	put_page(page);
+	folio_put(folio);
 out:
 	return ret;
 }
@@ -592,6 +591,76 @@ int sync_mapping_buffers(struct address_space *mapping)
 }
 EXPORT_SYMBOL(sync_mapping_buffers);
 
+/**
+ * generic_buffers_fsync_noflush - generic buffer fsync implementation
+ * for simple filesystems with no inode lock
+ *
+ * @file:	file to synchronize
+ * @start:	start offset in bytes
+ * @end:	end offset in bytes (inclusive)
+ * @datasync:	only synchronize essential metadata if true
+ *
+ * This is a generic implementation of the fsync method for simple
+ * filesystems which track all non-inode metadata in the buffers list
+ * hanging off the address_space structure.
+ */
+int generic_buffers_fsync_noflush(struct file *file, loff_t start, loff_t end,
+				  bool datasync)
+{
+	struct inode *inode = file->f_mapping->host;
+	int err;
+	int ret;
+
+	err = file_write_and_wait_range(file, start, end);
+	if (err)
+		return err;
+
+	ret = sync_mapping_buffers(inode->i_mapping);
+	if (!(inode->i_state & I_DIRTY_ALL))
+		goto out;
+	if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))
+		goto out;
+
+	err = sync_inode_metadata(inode, 1);
+	if (ret == 0)
+		ret = err;
+
+out:
+	/* check and advance again to catch errors after syncing out buffers */
+	err = file_check_and_advance_wb_err(file);
+	if (ret == 0)
+		ret = err;
+	return ret;
+}
+EXPORT_SYMBOL(generic_buffers_fsync_noflush);
+
+/**
+ * generic_buffers_fsync - generic buffer fsync implementation
+ * for simple filesystems with no inode lock
+ *
+ * @file:	file to synchronize
+ * @start:	start offset in bytes
+ * @end:	end offset in bytes (inclusive)
+ * @datasync:	only synchronize essential metadata if true
+ *
+ * This is a generic implementation of the fsync method for simple
+ * filesystems which track all non-inode metadata in the buffers list
+ * hanging off the address_space structure. This also makes sure that
+ * a device cache flush operation is called at the end.
+ */
+int generic_buffers_fsync(struct file *file, loff_t start, loff_t end,
+			  bool datasync)
+{
+	struct inode *inode = file->f_mapping->host;
+	int ret;
+
+	ret = generic_buffers_fsync_noflush(file, start, end, datasync);
+	if (!ret)
+		ret = blkdev_issue_flush(inode->i_sb->s_bdev);
+	return ret;
+}
+EXPORT_SYMBOL(generic_buffers_fsync);
+
 /*
  * Called when we've recently written block `bblock', and it is known that
  * `bblock' was for a buffer_boundary() buffer.  This means that the block at
@@ -907,8 +976,8 @@ struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size,
 }
 EXPORT_SYMBOL_GPL(alloc_page_buffers);
 
-static inline void
-link_dev_buffers(struct page *page, struct buffer_head *head)
+static inline void link_dev_buffers(struct folio *folio,
+		struct buffer_head *head)
 {
 	struct buffer_head *bh, *tail;
 
@@ -918,7 +987,7 @@ link_dev_buffers(struct page *page, struct buffer_head *head)
 		bh = bh->b_this_page;
 	} while (bh);
 	tail->b_this_page = head;
-	attach_page_private(page, head);
+	folio_attach_private(folio, head);
 }
 
 static sector_t blkdev_max_block(struct block_device *bdev, unsigned int size)
@@ -934,15 +1003,14 @@ static sector_t blkdev_max_block(struct block_device *bdev, unsigned int size)
 }
 
 /*
- * Initialise the state of a blockdev page's buffers.
+ * Initialise the state of a blockdev folio's buffers.
  */ 
-static sector_t
-init_page_buffers(struct page *page, struct block_device *bdev,
-			sector_t block, int size)
+static sector_t folio_init_buffers(struct folio *folio,
+		struct block_device *bdev, sector_t block, int size)
 {
-	struct buffer_head *head = page_buffers(page);
+	struct buffer_head *head = folio_buffers(folio);
 	struct buffer_head *bh = head;
-	int uptodate = PageUptodate(page);
+	bool uptodate = folio_test_uptodate(folio);
 	sector_t end_block = blkdev_max_block(bdev, size);
 
 	do {
@@ -976,7 +1044,7 @@ grow_dev_page(struct block_device *bdev, sector_t block,
 	      pgoff_t index, int size, int sizebits, gfp_t gfp)
 {
 	struct inode *inode = bdev->bd_inode;
-	struct page *page;
+	struct folio *folio;
 	struct buffer_head *bh;
 	sector_t end_block;
 	int ret = 0;
@@ -992,42 +1060,37 @@ grow_dev_page(struct block_device *bdev, sector_t block,
 	 */
 	gfp_mask |= __GFP_NOFAIL;
 
-	page = find_or_create_page(inode->i_mapping, index, gfp_mask);
+	folio = __filemap_get_folio(inode->i_mapping, index,
+			FGP_LOCK | FGP_ACCESSED | FGP_CREAT, gfp_mask);
 
-	BUG_ON(!PageLocked(page));
-
-	if (page_has_buffers(page)) {
-		bh = page_buffers(page);
+	bh = folio_buffers(folio);
+	if (bh) {
 		if (bh->b_size == size) {
-			end_block = init_page_buffers(page, bdev,
-						(sector_t)index << sizebits,
-						size);
+			end_block = folio_init_buffers(folio, bdev,
+					(sector_t)index << sizebits, size);
 			goto done;
 		}
-		if (!try_to_free_buffers(page_folio(page)))
+		if (!try_to_free_buffers(folio))
 			goto failed;
 	}
 
-	/*
-	 * Allocate some buffers for this page
-	 */
-	bh = alloc_page_buffers(page, size, true);
+	bh = folio_alloc_buffers(folio, size, true);
 
 	/*
-	 * Link the page to the buffers and initialise them.  Take the
+	 * Link the folio to the buffers and initialise them.  Take the
 	 * lock to be atomic wrt __find_get_block(), which does not
-	 * run under the page lock.
+	 * run under the folio lock.
 	 */
 	spin_lock(&inode->i_mapping->private_lock);
-	link_dev_buffers(page, bh);
-	end_block = init_page_buffers(page, bdev, (sector_t)index << sizebits,
-			size);
+	link_dev_buffers(folio, bh);
+	end_block = folio_init_buffers(folio, bdev,
+			(sector_t)index << sizebits, size);
 	spin_unlock(&inode->i_mapping->private_lock);
 done:
 	ret = (block < end_block) ? 1 : -ENXIO;
 failed:
-	unlock_page(page);
-	put_page(page);
+	folio_unlock(folio);
+	folio_put(folio);
 	return ret;
 }
 
@@ -1764,7 +1827,7 @@ static struct buffer_head *folio_create_buffers(struct folio *folio,
  * WB_SYNC_ALL, the writes are posted using REQ_SYNC; this
  * causes the writes to be flagged as synchronous writes.
  */
-int __block_write_full_page(struct inode *inode, struct page *page,
+int __block_write_full_folio(struct inode *inode, struct folio *folio,
 			get_block_t *get_block, struct writeback_control *wbc,
 			bh_end_io_t *handler)
 {
@@ -1776,14 +1839,14 @@ int __block_write_full_page(struct inode *inode, struct page *page,
 	int nr_underway = 0;
 	blk_opf_t write_flags = wbc_to_write_flags(wbc);
 
-	head = folio_create_buffers(page_folio(page), inode,
+	head = folio_create_buffers(folio, inode,
 				    (1 << BH_Dirty) | (1 << BH_Uptodate));
 
 	/*
 	 * 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 page stays dirty.
+	 * 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.
@@ -1793,7 +1856,7 @@ int __block_write_full_page(struct inode *inode, struct page *page,
 	blocksize = bh->b_size;
 	bbits = block_size_bits(blocksize);
 
-	block = (sector_t)page->index << (PAGE_SHIFT - bbits);
+	block = (sector_t)folio->index << (PAGE_SHIFT - bbits);
 	last_block = (i_size_read(inode) - 1) >> bbits;
 
 	/*
@@ -1804,7 +1867,7 @@ int __block_write_full_page(struct inode *inode, struct page *page,
 		if (block > last_block) {
 			/*
 			 * mapped buffers outside i_size will occur, because
-			 * this page can be outside i_size when there is a
+			 * this folio can be outside i_size when there is a
 			 * truncate in progress.
 			 */
 			/*
@@ -1834,7 +1897,7 @@ int __block_write_full_page(struct inode *inode, struct page *page,
 			continue;
 		/*
 		 * If it's a fully non-blocking write attempt and we cannot
-		 * lock the buffer then redirty the page.  Note that this can
+		 * lock the buffer then redirty the folio.  Note that this can
 		 * potentially cause a busy-wait loop from writeback threads
 		 * and kswapd activity, but those code paths have their own
 		 * higher-level throttling.
@@ -1842,7 +1905,7 @@ int __block_write_full_page(struct inode *inode, struct page *page,
 		if (wbc->sync_mode != WB_SYNC_NONE) {
 			lock_buffer(bh);
 		} else if (!trylock_buffer(bh)) {
-			redirty_page_for_writepage(wbc, page);
+			folio_redirty_for_writepage(wbc, folio);
 			continue;
 		}
 		if (test_clear_buffer_dirty(bh)) {
@@ -1853,11 +1916,11 @@ int __block_write_full_page(struct inode *inode, struct page *page,
 	} while ((bh = bh->b_this_page) != head);
 
 	/*
-	 * The page and its buffers are protected by PageWriteback(), so we can
-	 * drop the bh refcounts early.
+	 * The folio and its buffers are protected by the writeback flag,
+	 * so we can drop the bh refcounts early.
 	 */
-	BUG_ON(PageWriteback(page));
-	set_page_writeback(page);
+	BUG_ON(folio_test_writeback(folio));
+	folio_start_writeback(folio);
 
 	do {
 		struct buffer_head *next = bh->b_this_page;
@@ -1867,20 +1930,20 @@ int __block_write_full_page(struct inode *inode, struct page *page,
 		}
 		bh = next;
 	} while (bh != head);
-	unlock_page(page);
+	folio_unlock(folio);
 
 	err = 0;
 done:
 	if (nr_underway == 0) {
 		/*
-		 * The page was marked dirty, but the buffers were
+		 * The folio was marked dirty, but the buffers were
 		 * clean.  Someone wrote them back by hand with
 		 * write_dirty_buffer/submit_bh.  A rare case.
 		 */
-		end_page_writeback(page);
+		folio_end_writeback(folio);
 
 		/*
-		 * The page and buffer_heads can be released at any time from
+		 * The folio and buffer_heads can be released at any time from
 		 * here on.
 		 */
 	}
@@ -1891,7 +1954,7 @@ recover:
 	 * ENOSPC, or some other error.  We may already have added some
 	 * blocks to the file, so we need to write these out to avoid
 	 * exposing stale data.
-	 * The page is currently locked and not marked for writeback
+	 * The folio is currently locked and not marked for writeback
 	 */
 	bh = head;
 	/* Recovery: lock and submit the mapped buffers */
@@ -1903,15 +1966,15 @@ recover:
 		} else {
 			/*
 			 * The buffer may have been set dirty during
-			 * attachment to a dirty page.
+			 * attachment to a dirty folio.
 			 */
 			clear_buffer_dirty(bh);
 		}
 	} while ((bh = bh->b_this_page) != head);
-	SetPageError(page);
-	BUG_ON(PageWriteback(page));
-	mapping_set_error(page->mapping, err);
-	set_page_writeback(page);
+	folio_set_error(folio);
+	BUG_ON(folio_test_writeback(folio));
+	mapping_set_error(folio->mapping, err);
+	folio_start_writeback(folio);
 	do {
 		struct buffer_head *next = bh->b_this_page;
 		if (buffer_async_write(bh)) {
@@ -1921,39 +1984,40 @@ recover:
 		}
 		bh = next;
 	} while (bh != head);
-	unlock_page(page);
+	folio_unlock(folio);
 	goto done;
 }
-EXPORT_SYMBOL(__block_write_full_page);
+EXPORT_SYMBOL(__block_write_full_folio);
 
 /*
- * If a page has any new buffers, zero them out here, and mark them uptodate
+ * If a folio has any new buffers, zero them out here, and mark them uptodate
  * and dirty so they'll be written out (in order to prevent uninitialised
  * block data from leaking). And clear the new bit.
  */
-void page_zero_new_buffers(struct page *page, unsigned from, unsigned to)
+void folio_zero_new_buffers(struct folio *folio, size_t from, size_t to)
 {
-	unsigned int block_start, block_end;
+	size_t block_start, block_end;
 	struct buffer_head *head, *bh;
 
-	BUG_ON(!PageLocked(page));
-	if (!page_has_buffers(page))
+	BUG_ON(!folio_test_locked(folio));
+	head = folio_buffers(folio);
+	if (!head)
 		return;
 
-	bh = head = page_buffers(page);
+	bh = head;
 	block_start = 0;
 	do {
 		block_end = block_start + bh->b_size;
 
 		if (buffer_new(bh)) {
 			if (block_end > from && block_start < to) {
-				if (!PageUptodate(page)) {
-					unsigned start, size;
+				if (!folio_test_uptodate(folio)) {
+					size_t start, xend;
 
 					start = max(from, block_start);
-					size = min(to, block_end) - start;
+					xend = min(to, block_end);
 
-					zero_user(page, start, size);
+					folio_zero_segment(folio, start, xend);
 					set_buffer_uptodate(bh);
 				}
 
@@ -1966,7 +2030,7 @@ void page_zero_new_buffers(struct page *page, unsigned from, unsigned to)
 		bh = bh->b_this_page;
 	} while (bh != head);
 }
-EXPORT_SYMBOL(page_zero_new_buffers);
+EXPORT_SYMBOL(folio_zero_new_buffers);
 
 static void
 iomap_to_bh(struct inode *inode, sector_t block, struct buffer_head *bh,
@@ -2104,7 +2168,7 @@ int __block_write_begin_int(struct folio *folio, loff_t pos, unsigned len,
 			err = -EIO;
 	}
 	if (unlikely(err))
-		page_zero_new_buffers(&folio->page, from, to);
+		folio_zero_new_buffers(folio, from, to);
 	return err;
 }
 
@@ -2116,15 +2180,15 @@ int __block_write_begin(struct page *page, loff_t pos, unsigned len,
 }
 EXPORT_SYMBOL(__block_write_begin);
 
-static int __block_commit_write(struct inode *inode, struct page *page,
-		unsigned from, unsigned to)
+static int __block_commit_write(struct inode *inode, struct folio *folio,
+		size_t from, size_t to)
 {
-	unsigned block_start, block_end;
-	int partial = 0;
+	size_t block_start, block_end;
+	bool partial = false;
 	unsigned blocksize;
 	struct buffer_head *bh, *head;
 
-	bh = head = page_buffers(page);
+	bh = head = folio_buffers(folio);
 	blocksize = bh->b_size;
 
 	block_start = 0;
@@ -2132,7 +2196,7 @@ static int __block_commit_write(struct inode *inode, struct page *page,
 		block_end = block_start + blocksize;
 		if (block_end <= from || block_start >= to) {
 			if (!buffer_uptodate(bh))
-				partial = 1;
+				partial = true;
 		} else {
 			set_buffer_uptodate(bh);
 			mark_buffer_dirty(bh);
@@ -2147,11 +2211,11 @@ static int __block_commit_write(struct inode *inode, struct page *page,
 	/*
 	 * If this is a partial write which happened to make all buffers
 	 * uptodate then we can optimize away a bogus read_folio() for
-	 * the next read(). Here we 'discover' whether the page went
+	 * the next read(). Here we 'discover' whether the folio went
 	 * uptodate as a result of this (potentially partial) write.
 	 */
 	if (!partial)
-		SetPageUptodate(page);
+		folio_mark_uptodate(folio);
 	return 0;
 }
 
@@ -2188,10 +2252,9 @@ int block_write_end(struct file *file, struct address_space *mapping,
 			loff_t pos, unsigned len, unsigned copied,
 			struct page *page, void *fsdata)
 {
+	struct folio *folio = page_folio(page);
 	struct inode *inode = mapping->host;
-	unsigned start;
-
-	start = pos & (PAGE_SIZE - 1);
+	size_t start = pos - folio_pos(folio);
 
 	if (unlikely(copied < len)) {
 		/*
@@ -2203,18 +2266,18 @@ int block_write_end(struct file *file, struct address_space *mapping,
 		 * read_folio might come in and destroy our partial write.
 		 *
 		 * Do the simplest thing, and just treat any short write to a
-		 * non uptodate page as a zero-length write, and force the
+		 * non uptodate folio as a zero-length write, and force the
 		 * caller to redo the whole thing.
 		 */
-		if (!PageUptodate(page))
+		if (!folio_test_uptodate(folio))
 			copied = 0;
 
-		page_zero_new_buffers(page, start+copied, start+len);
+		folio_zero_new_buffers(folio, start+copied, start+len);
 	}
-	flush_dcache_page(page);
+	flush_dcache_folio(folio);
 
 	/* This could be a short (even 0-length) commit */
-	__block_commit_write(inode, page, start, start+copied);
+	__block_commit_write(inode, folio, start, start + copied);
 
 	return copied;
 }
@@ -2537,8 +2600,9 @@ EXPORT_SYMBOL(cont_write_begin);
 
 int block_commit_write(struct page *page, unsigned from, unsigned to)
 {
-	struct inode *inode = page->mapping->host;
-	__block_commit_write(inode,page,from,to);
+	struct folio *folio = page_folio(page);
+	struct inode *inode = folio->mapping->host;
+	__block_commit_write(inode, folio, from, to);
 	return 0;
 }
 EXPORT_SYMBOL(block_commit_write);
@@ -2564,38 +2628,37 @@ EXPORT_SYMBOL(block_commit_write);
 int block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf,
 			 get_block_t get_block)
 {
-	struct page *page = vmf->page;
+	struct folio *folio = page_folio(vmf->page);
 	struct inode *inode = file_inode(vma->vm_file);
 	unsigned long end;
 	loff_t size;
 	int ret;
 
-	lock_page(page);
+	folio_lock(folio);
 	size = i_size_read(inode);
-	if ((page->mapping != inode->i_mapping) ||
-	    (page_offset(page) > size)) {
+	if ((folio->mapping != inode->i_mapping) ||
+	    (folio_pos(folio) >= size)) {
 		/* We overload EFAULT to mean page got truncated */
 		ret = -EFAULT;
 		goto out_unlock;
 	}
 
-	/* page is wholly or partially inside EOF */
-	if (((page->index + 1) << PAGE_SHIFT) > size)
-		end = size & ~PAGE_MASK;
-	else
-		end = PAGE_SIZE;
+	end = folio_size(folio);
+	/* folio is wholly or partially inside EOF */
+	if (folio_pos(folio) + end > size)
+		end = size - folio_pos(folio);
 
-	ret = __block_write_begin(page, 0, end, get_block);
+	ret = __block_write_begin_int(folio, 0, end, get_block, NULL);
 	if (!ret)
-		ret = block_commit_write(page, 0, end);
+		ret = __block_commit_write(inode, folio, 0, end);
 
 	if (unlikely(ret < 0))
 		goto out_unlock;
-	set_page_dirty(page);
-	wait_for_stable_page(page);
+	folio_mark_dirty(folio);
+	folio_wait_stable(folio);
 	return 0;
 out_unlock:
-	unlock_page(page);
+	folio_unlock(folio);
 	return ret;
 }
 EXPORT_SYMBOL(block_page_mkwrite);
@@ -2604,17 +2667,16 @@ int block_truncate_page(struct address_space *mapping,
 			loff_t from, get_block_t *get_block)
 {
 	pgoff_t index = from >> PAGE_SHIFT;
-	unsigned offset = from & (PAGE_SIZE-1);
 	unsigned blocksize;
 	sector_t iblock;
-	unsigned length, pos;
+	size_t offset, length, pos;
 	struct inode *inode = mapping->host;
-	struct page *page;
+	struct folio *folio;
 	struct buffer_head *bh;
 	int err = 0;
 
 	blocksize = i_blocksize(inode);
-	length = offset & (blocksize - 1);
+	length = from & (blocksize - 1);
 
 	/* Block boundary? Nothing to do */
 	if (!length)
@@ -2623,15 +2685,18 @@ int block_truncate_page(struct address_space *mapping,
 	length = blocksize - length;
 	iblock = (sector_t)index << (PAGE_SHIFT - inode->i_blkbits);
 	
-	page = grab_cache_page(mapping, index);
-	if (!page)
-		return -ENOMEM;
+	folio = filemap_grab_folio(mapping, index);
+	if (IS_ERR(folio))
+		return PTR_ERR(folio);
 
-	if (!page_has_buffers(page))
-		create_empty_buffers(page, blocksize, 0);
+	bh = folio_buffers(folio);
+	if (!bh) {
+		folio_create_empty_buffers(folio, blocksize, 0);
+		bh = folio_buffers(folio);
+	}
 
 	/* Find the buffer that contains "offset" */
-	bh = page_buffers(page);
+	offset = offset_in_folio(folio, from);
 	pos = blocksize;
 	while (offset >= pos) {
 		bh = bh->b_this_page;
@@ -2650,7 +2715,7 @@ int block_truncate_page(struct address_space *mapping,
 	}
 
 	/* Ok, it's mapped. Make sure it's up-to-date */
-	if (PageUptodate(page))
+	if (folio_test_uptodate(folio))
 		set_buffer_uptodate(bh);
 
 	if (!buffer_uptodate(bh) && !buffer_delay(bh) && !buffer_unwritten(bh)) {
@@ -2660,12 +2725,12 @@ int block_truncate_page(struct address_space *mapping,
 			goto unlock;
 	}
 
-	zero_user(page, offset, length);
+	folio_zero_range(folio, offset, length);
 	mark_buffer_dirty(bh);
 
 unlock:
-	unlock_page(page);
-	put_page(page);
+	folio_unlock(folio);
+	folio_put(folio);
 
 	return err;
 }
@@ -2677,33 +2742,32 @@ EXPORT_SYMBOL(block_truncate_page);
 int block_write_full_page(struct page *page, get_block_t *get_block,
 			struct writeback_control *wbc)
 {
-	struct inode * const inode = page->mapping->host;
+	struct folio *folio = page_folio(page);
+	struct inode * const inode = folio->mapping->host;
 	loff_t i_size = i_size_read(inode);
-	const pgoff_t end_index = i_size >> PAGE_SHIFT;
-	unsigned offset;
 
-	/* Is the page fully inside i_size? */
-	if (page->index < end_index)
-		return __block_write_full_page(inode, page, get_block, wbc,
+	/* Is the folio fully inside i_size? */
+	if (folio_pos(folio) + folio_size(folio) <= i_size)
+		return __block_write_full_folio(inode, folio, get_block, wbc,
 					       end_buffer_async_write);
 
-	/* Is the page fully outside i_size? (truncate in progress) */
-	offset = i_size & (PAGE_SIZE-1);
-	if (page->index >= end_index+1 || !offset) {
-		unlock_page(page);
+	/* Is the folio fully outside i_size? (truncate in progress) */
+	if (folio_pos(folio) >= i_size) {
+		folio_unlock(folio);
 		return 0; /* don't care */
 	}
 
 	/*
-	 * The page straddles i_size.  It must be zeroed out on each and every
+	 * The folio straddles i_size.  It must be zeroed out on each and every
 	 * writepage invocation because it may be mmapped.  "A file is mapped
 	 * in multiples of the page size.  For a file that is not a multiple of
-	 * the  page size, the remaining memory is zeroed when mapped, and
+	 * the page size, the remaining memory is zeroed when mapped, and
 	 * writes to that region are not written out to the file."
 	 */
-	zero_user_segment(page, offset, PAGE_SIZE);
-	return __block_write_full_page(inode, page, get_block, wbc,
-							end_buffer_async_write);
+	folio_zero_segment(folio, offset_in_folio(folio, i_size),
+			folio_size(folio));
+	return __block_write_full_folio(inode, folio, get_block, wbc,
+			end_buffer_async_write);
 }
 EXPORT_SYMBOL(block_write_full_page);
 
@@ -2760,8 +2824,7 @@ static void submit_bh_wbc(blk_opf_t opf, struct buffer_head *bh,
 
 	bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
 
-	bio_add_page(bio, bh->b_page, bh->b_size, bh_offset(bh));
-	BUG_ON(bio->bi_iter.bi_size != bh->b_size);
+	__bio_add_page(bio, bh->b_page, bh->b_size, bh_offset(bh));
 
 	bio->bi_end_io = end_bio_bh_io_sync;
 	bio->bi_private = bh;