diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 87ccb3438bec..cac8a88660d8 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -207,23 +207,22 @@ struct iomap_readpage_ctx {
 
 static void
 iomap_read_inline_data(struct inode *inode, struct page *page,
-		struct iomap *iomap)
+		struct iomap *iomap, loff_t pos)
 {
-	size_t size = i_size_read(inode);
+	unsigned int size, poff = offset_in_page(pos);
 	void *addr;
 
-	if (PageUptodate(page))
-		return;
-
-	BUG_ON(page_has_private(page));
-	BUG_ON(page->index);
-	BUG_ON(size > PAGE_SIZE - offset_in_page(iomap->inline_data));
+	/* inline source data must be inside a single page */
+	BUG_ON(iomap->length > PAGE_SIZE - offset_in_page(iomap->inline_data));
+	/* handle tail-packing blocks cross the current page into the next */
+	size = min_t(unsigned int, iomap->length + pos - iomap->offset,
+		     PAGE_SIZE - poff);
 
 	addr = kmap_atomic(page);
-	memcpy(addr, iomap->inline_data, size);
-	memset(addr + size, 0, PAGE_SIZE - size);
+	memcpy(addr + poff, iomap->inline_data - iomap->offset + pos, size);
+	memset(addr + poff + size, 0, PAGE_SIZE - poff - size);
 	kunmap_atomic(addr);
-	SetPageUptodate(page);
+	iomap_set_range_uptodate(page, poff, PAGE_SIZE - poff);
 }
 
 static inline bool iomap_block_needs_zeroing(struct inode *inode,
@@ -246,18 +245,19 @@ iomap_readpage_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
 	unsigned poff, plen;
 	sector_t sector;
 
-	if (iomap->type == IOMAP_INLINE) {
-		WARN_ON_ONCE(pos);
-		iomap_read_inline_data(inode, page, iomap);
-		return PAGE_SIZE;
-	}
-
-	/* zero post-eof blocks as the page may be mapped */
 	iop = iomap_page_create(inode, page);
+	/* needs to skip some leading uptodated blocks */
 	iomap_adjust_read_range(inode, iop, &pos, length, &poff, &plen);
 	if (plen == 0)
 		goto done;
 
+	if (iomap->type == IOMAP_INLINE) {
+		iomap_read_inline_data(inode, page, iomap, pos);
+		plen = PAGE_SIZE - poff;
+		goto done;
+	}
+
+	/* zero post-eof blocks as the page may be mapped */
 	if (iomap_block_needs_zeroing(inode, iomap, pos)) {
 		zero_user(page, poff, plen);
 		iomap_set_range_uptodate(page, poff, plen);
@@ -589,6 +589,18 @@ __iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, int flags,
 	return 0;
 }
 
+static int iomap_write_begin_inline(struct inode *inode, loff_t pos,
+		struct page *page, struct iomap *srcmap)
+{
+	/* needs more work for the tailpacking case, disable for now */
+	if (WARN_ON_ONCE(pos != 0))
+		return -EIO;
+	if (PageUptodate(page))
+		return 0;
+	iomap_read_inline_data(inode, page, srcmap, pos);
+	return 0;
+}
+
 static int
 iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, unsigned flags,
 		struct page **pagep, struct iomap *iomap, struct iomap *srcmap)
@@ -618,7 +630,7 @@ iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, unsigned flags,
 	}
 
 	if (srcmap->type == IOMAP_INLINE)
-		iomap_read_inline_data(inode, page, srcmap);
+		status = iomap_write_begin_inline(inode, pos, page, srcmap);
 	else if (iomap->flags & IOMAP_F_BUFFER_HEAD)
 		status = __block_write_begin_int(page, pos, len, NULL, srcmap);
 	else
diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
index 9398b8c31323..ee6309967b77 100644
--- a/fs/iomap/direct-io.c
+++ b/fs/iomap/direct-io.c
@@ -379,22 +379,25 @@ iomap_dio_inline_actor(struct inode *inode, loff_t pos, loff_t length,
 {
 	struct iov_iter *iter = dio->submit.iter;
 	size_t copied;
+	void *dst = iomap->inline_data + pos - iomap->offset;
 
-	BUG_ON(pos + length > PAGE_SIZE - offset_in_page(iomap->inline_data));
+	/* inline data must be inside a single page */
+	BUG_ON(length > PAGE_SIZE - offset_in_page(iomap->inline_data));
 
 	if (dio->flags & IOMAP_DIO_WRITE) {
 		loff_t size = inode->i_size;
 
 		if (pos > size)
-			memset(iomap->inline_data + size, 0, pos - size);
-		copied = copy_from_iter(iomap->inline_data + pos, length, iter);
+			memset(iomap->inline_data + size - iomap->offset,
+			       0, pos - size);
+		copied = copy_from_iter(dst, length, iter);
 		if (copied) {
 			if (pos + copied > size)
 				i_size_write(inode, pos + copied);
 			mark_inode_dirty(inode);
 		}
 	} else {
-		copied = copy_to_iter(iomap->inline_data + pos, length, iter);
+		copied = copy_to_iter(dst, length, iter);
 	}
 	dio->size += copied;
 	return copied;
