[0/2] fix sync to flush processor cache for ext4 DAX files

Message

Kani, Toshi Sept. 11, 2018, 3:42 p.m. UTC

This patchset fixes an issue that sync syscall to an existing DAX file
does not flush processor cache.

Patch 1/2 adds a check to skip the journal inode. It's a bit awkward,
but I could not find a beter way to get the journal inode.

Patch 2/2 fixes the issue by moving up ext4_set_inode_flags() before
ext4_set_aops() in ext4_iget(). This assumes updated i_flags is harmless
in the error cases after the moved-up ext4_set_inode_flags(). Please
review.

---
Toshi Kani (2):
 1/2 ext4, dax: update dax check to skip journal inode
 2/2 ext4, dax: set ext4_dax_aops for dax files

---
 fs/ext4/ext4_jbd2.h | 8 ++++++++
 fs/ext4/inode.c     | 5 ++++-
 2 files changed, 12 insertions(+), 1 deletion(-)