On 06/03, Greg KH wrote:
> On Thu, Jun 03, 2021 at 09:50:38AM +0000, Daniel Rosenberg wrote:
> > Older kernels don't support encryption with casefolding. This adds
> > the sysfs entry encrypted_casefold to show support for those combined
> > features. Support for this feature was originally added by
> > commit 7ad08a58bf67 ("f2fs: Handle casefolding with Encryption")
> >
> > Fixes: 7ad08a58bf67 ("f2fs: Handle casefolding with Encryption")
> > Cc: stable@xxxxxxxxxxxxxxx # v5.11+
> > Signed-off-by: Daniel Rosenberg <drosen@xxxxxxxxxx>
> > ---
> > fs/f2fs/sysfs.c | 15 +++++++++++++--
> > 1 file changed, 13 insertions(+), 2 deletions(-)
> >
> > diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
> > index 09e3f258eb52..6604291a3cdf 100644
> > --- a/fs/f2fs/sysfs.c
> > +++ b/fs/f2fs/sysfs.c
> > @@ -161,6 +161,9 @@ static ssize_t features_show(struct f2fs_attr *a,
> > if (f2fs_sb_has_compression(sbi))
> > len += scnprintf(buf + len, PAGE_SIZE - len, "%s%s",
> > len ? ", " : "", "compression");
> > + if (f2fs_sb_has_casefold(sbi) && f2fs_sb_has_encrypt(sbi))
> > + len += scnprintf(buf + len, PAGE_SIZE - len, "%s%s",
> > + len ? ", " : "", "encrypted_casefold");
> > len += scnprintf(buf + len, PAGE_SIZE - len, "%s%s",
> > len ? ", " : "", "pin_file");
> > len += scnprintf(buf + len, PAGE_SIZE - len, "\n");
>
> This is a HUGE abuse of sysfs and should not be encouraged and added to.
This feature entry was originally added in 2017. Let me try to clean this up
after merging this.
>
> Please make these "one value per file" and do not keep growing a single
> file that has to be parsed otherwise you will break userspace tools.
>
> And I don't see a Documentation/ABI/ entry for this either :(
There is in Documentation/ABI/testing/sysfs-fs-f2fs.
>
> not good...
>
> greg k-h
