Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> writes: > On Thu, May 14, 2015 at 12:35:02PM -0500, Eric W. Biederman wrote: >> >> Add two functions sysfs_create_empty_dir and sysfs_remove_empty_dir >> that hang a permanently empty directory off of a kobject or remove >> a permanently emptpy directory hanging from a kobject. Export >> these new functions so modular filesystems can use them. >> >> As all permanently empty directories are, are names and used >> for mouting other filesystems this seems like the right abstraction. > > That sentence doesn't make much sense, cut and paste? Probably one edit too many or too few depending on how you look at it. What I meant is that since the only interesting thing about a permanently empty directory is it's name, treating them like sysfs files rather than normal sysfs directories which require a kobject seems like the right abstraction. >> Cc: stable@xxxxxxxxxxxxxxx >> Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> >> --- >> fs/sysfs/dir.c | 34 ++++++++++++++++++++++++++++++++++ >> include/linux/sysfs.h | 16 ++++++++++++++++ >> 2 files changed, 50 insertions(+) >> >> diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c >> index 0b45ff42f374..8244741474d7 100644 >> --- a/fs/sysfs/dir.c >> +++ b/fs/sysfs/dir.c >> @@ -121,3 +121,37 @@ int sysfs_move_dir_ns(struct kobject *kobj, struct kobject *new_parent_kobj, >> >> return kernfs_rename_ns(kn, new_parent, kn->name, new_ns); >> } >> + >> +/** >> + * sysfs_create_empty_dir - create an always empty directory >> + * @parent_kobj: kobject that will contain this always empty directory >> + * @name: The name of the always empty directory to add >> + */ >> +int sysfs_create_empty_dir(struct kobject *parent_kobj, const char *name) > > As this really is just a mount point, how about we be explicit with > this and call the function: > sysfs_create_mount_point() > sysfs_remove_mount_point() > That makes more sense in the long run, otherwise if you just want to > create an empty directory in sysfs, you can do so without making an > "empty" kobject and some people might do that accidentally in the > future. This makes it more obvious as to what is going on. Yeah. That seems fairly reasonable. My brain is on the edge between the functional description of creating a permanently empty directory, and the usage based description (creating a directory to mount filesystems on). But I agree a name that makes it totally obvious we are creating a directory to mount something on is going to be more usable and comprehensible. My head doesn't like sysfs_create_mount_point() as a mount point can be a file. But I will put it on the back burner and see if I can come up with something better, and if not sysfs_create_mount_point it is. Brainstorming: sysfs_create_expected_mount_point() sysfs_reserve_dir_for_mount() sysfs_create_dir_mount_point() sysfs_create_expected_mount_point() Partly I think I would like to rename the proc, sysctl and infrastructure bit as well (consistency and clarity is good). Where I get stuck is how do I ask the question: I see this directory is a mount point, is it a directory whose sole purpose in life is to be a mount point? In the context of that question I like my naming of empty_dir as it conveys what I am interested in. But I like the sysfs_create_mount_point for general use. Maybe I won't make my names consistent. I don't know. I am putting this naming question on the back burner for a bit. Eric -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
