fuse: Add posix ACL support

Add a new INIT flag, FUSE_POSIX_ACL, for negotiating ACL support with
userspace.  When it is set in the INIT response, ACL support will be
enabled.  ACL support also implies "default_permissions".

When ACL support is enabled, the kernel will cache and have responsibility
for enforcing ACLs.  ACL xattrs will be passed to userspace, which is
responsible for updating the ACLs in the filesystem, keeping the file mode
in sync, and inheritance of default ACLs when new filesystem nodes are
created.

Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h
index 14ca2f10d354..42fa977e3b14 100644
--- a/include/uapi/linux/fuse.h
+++ b/include/uapi/linux/fuse.h
@@ -111,6 +111,7 @@
  *
  *  7.26
  *  - add FUSE_HANDLE_KILLPRIV
+ *  - add FUSE_POSIX_ACL
  */
 
 #ifndef _LINUX_FUSE_H
@@ -242,6 +243,7 @@ struct fuse_file_lock {
  * FUSE_NO_OPEN_SUPPORT: kernel supports zero-message opens
  * FUSE_PARALLEL_DIROPS: allow parallel lookups and readdir
  * FUSE_HANDLE_KILLPRIV: fs handles killing suid/sgid/cap on write/chown/trunc
+ * FUSE_POSIX_ACL: filesystem supports posix acls
  */
 #define FUSE_ASYNC_READ         (1 << 0)
 #define FUSE_POSIX_LOCKS        (1 << 1)
@@ -263,6 +265,7 @@ struct fuse_file_lock {
 #define FUSE_NO_OPEN_SUPPORT    (1 << 17)
 #define FUSE_PARALLEL_DIROPS    (1 << 18)
 #define FUSE_HANDLE_KILLPRIV    (1 << 19)
+#define FUSE_POSIX_ACL          (1 << 20)
 
 /**
  * CUSE INIT request/reply flags