The current kmemdup() based allocation for IOMAP_INLINE can result in
inline_data pointer having a non-zero page offset. This causes
iomap_inline_data_valid() to fail the check:
iomap->length <= PAGE_SIZE - offset_in_page(iomap->inline_data)
and triggers the kernel BUG at fs/iomap/buffered-io.c:1061.
This particularly affects workloads with frequent small file access
(e.g. Firefox Nightly profile on NTFS with bind mount) when using the
new ntfs. This fix this by allocating a full page with alloc_page() so that
page_address() always returns a page-aligned address.
Reviewed-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
36ee131319