To support DAX pmd mappings with unmodified applications, filesystems need to align an mmap address by the pmd size.
Call dax_get_unmapped_area() from f_op->get_unmapped_area. Note, there is no change in behavior for a non-DAX file. Signed-off-by: Toshi Kani <[email protected]> Cc: Theodore Ts'o <[email protected]> Cc: Andreas Dilger <[email protected]> Cc: Jan Kara <[email protected]> Cc: Dan Williams <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Ross Zwisler <[email protected]> Cc: <[email protected]> --- fs/ext4/file.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/ext4/file.c b/fs/ext4/file.c index fa2208b..2abc57b 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -708,6 +708,9 @@ const struct file_operations ext4_file_operations = { .open = ext4_file_open, .release = ext4_release_file, .fsync = ext4_sync_file, +#ifdef CONFIG_FS_DAX + .get_unmapped_area = dax_get_unmapped_area, +#endif .splice_read = generic_file_splice_read, .splice_write = iter_file_splice_write, .fallocate = ext4_fallocate,
