iomap: pass private data to iomap_zero_range

Allow the file system to pass private data which can be used by the
iomap_begin and iomap_end methods through the private pointer in the
iomap_iter structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250206064035.2323428-11-hch@lst.de
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Author: Christoph Hellwig

fs/gfs2/bmap.c

@@ -1300,7 +1300,8 @@ static int gfs2_block_zero_range(struct inode *inode, loff_t from,
 				 unsigned int length)
 {
 	BUG_ON(current->journal_info);
-	return iomap_zero_range(inode, from, length, NULL, &gfs2_iomap_ops);
+	return iomap_zero_range(inode, from, length, NULL, &gfs2_iomap_ops,
+			NULL);
 }
 
 #define GFS2_JTRUNC_REVOKES 8192

fs/iomap/buffered-io.c

@@ -1391,13 +1391,14 @@ static loff_t iomap_zero_iter(struct iomap_iter *iter, bool *did_zero)
 
 int
 iomap_zero_range(struct inode *inode, loff_t pos, loff_t len, bool *did_zero,
-		const struct iomap_ops *ops)
+		const struct iomap_ops *ops, void *private)
 {
 	struct iomap_iter iter = {
 		.inode		= inode,
 		.pos		= pos,
 		.len		= len,
 		.flags		= IOMAP_ZERO,
+		.private	= private,
 	};
 	struct address_space *mapping = inode->i_mapping;
 	unsigned int blocksize = i_blocksize(inode);
@@ -1465,7 +1466,8 @@ iomap_truncate_page(struct inode *inode, loff_t pos, bool *did_zero,
 	/* Block boundary? Nothing to do */
 	if (!off)
 		return 0;
-	return iomap_zero_range(inode, pos, blocksize - off, did_zero, ops);
+	return iomap_zero_range(inode, pos, blocksize - off, did_zero, ops,
+			NULL);
 }
 EXPORT_SYMBOL_GPL(iomap_truncate_page);
 

fs/xfs/xfs_iomap.c

@@ -1497,7 +1497,7 @@ xfs_zero_range(
 		return dax_zero_range(inode, pos, len, did_zero,
 				      &xfs_dax_write_iomap_ops);
 	return iomap_zero_range(inode, pos, len, did_zero,
-				&xfs_buffered_write_iomap_ops);
+				&xfs_buffered_write_iomap_ops, NULL);
 }
 
 int

include/linux/iomap.h

@@ -313,7 +313,7 @@ bool iomap_dirty_folio(struct address_space *mapping, struct folio *folio);
 int iomap_file_unshare(struct inode *inode, loff_t pos, loff_t len,
 		const struct iomap_ops *ops);
 int iomap_zero_range(struct inode *inode, loff_t pos, loff_t len,
-		bool *did_zero, const struct iomap_ops *ops);
+		bool *did_zero, const struct iomap_ops *ops, void *private);
 int iomap_truncate_page(struct inode *inode, loff_t pos, bool *did_zero,
 		const struct iomap_ops *ops);
 vm_fault_t iomap_page_mkwrite(struct vm_fault *vmf, const struct iomap_ops *ops,