diff options
| author | Miklos Szeredi | 2019-05-31 11:27:25 +0200 |
|---|---|---|
| committer | Miklos Szeredi | 2019-05-31 11:27:25 +0200 |
| commit | 5d3211b651a012bc77410ebf097b7271a7ce5c95 (patch) | |
| tree | daeb13ad09e563e8cfda372dd64a4813aa174d0e /Documentation/filesystems | |
| parent | 146d62e5a5867fbf84490d82455718bfb10fe824 (diff) | |
ovl: doc: add non-standard corner cases
While most corner cases have already been dealt with, some remain and
should be documented.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Diffstat (limited to 'Documentation/filesystems')
| -rw-r--r-- | Documentation/filesystems/overlayfs.txt | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/Documentation/filesystems/overlayfs.txt b/Documentation/filesystems/overlayfs.txt index eef7d9d259e8..1da2f1668f08 100644 --- a/Documentation/filesystems/overlayfs.txt +++ b/Documentation/filesystems/overlayfs.txt @@ -336,8 +336,20 @@ the copied layers will fail the verification of the lower root file handle. Non-standard behavior --------------------- -Overlayfs can now act as a POSIX compliant filesystem with the following -features turned on: +Current version of overlayfs can act as a mostly POSIX compliant +filesystem. + +This is the list of cases that overlayfs doesn't currently handle: + +a) POSIX mandates updating st_atime for reads. This is currently not +done in the case when the file resides on a lower layer. + +b) If a file residing on a lower layer is opened for read-only and then +memory mapped with MAP_SHARED, then subsequent changes to the file are not +reflected in the memory mapping. + +The following options allow overlayfs to act more like a standards +compliant filesystem: 1) "redirect_dir" |