Re: [PATCH v2] kheaders: Simplify attribute through __BIN_ATTR_SIMPLE_RO()

[Thomas Weißschuh]

Hi Masahiro,

On 2024-12-28 23:52:13+0900, Masahiro Yamada wrote:
> On Sat, Dec 21, 2024 at 11:09 PM Thomas Weißschuh <linux@xxxxxxxxxxxxxx> wrote:
> >
> > The utility macro from the sysfs core is sufficient to implement this
> > attribute. Make use of it.
> >
> > Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
> 
> 
> Applied to linux-kbuild. Thanks.

Thanks, but FYI it is also already applied to the driver-core tree.
Unfortunately Greg's confirmation mails don't go to the list.

IMO having an explicit maintainer for this file could avoid this issue
in the future.

> > ---
> > Changes in v2:
> > - Use __BIN_ATTR_SIMPLE_RO() (Thanks Masahiro)
> > - Link to v1: https://lore.kernel.org/r/20241215-sysfs-const-bin_attr-kheaders-v1-1-319bbd50e224@xxxxxxxxxxxxxx
> > ---
> > __BIN_ATTR() is used over the normal struct initializer because it is
> > shorter and can also handle the transition to const struct bin_attr
> > callbacks.
> > If you prefer, I can switch that back, but it will introduce a trivial
> > conflict with [0].
> >
> > Note: There is no formal maintainer for that source file.
> >
> > [0] https://lore.kernel.org/lkml/20241205-sysfs-const-bin_attr-simple-v1-0-4a4e4ced71e3@xxxxxxxxxxxxxx/
> > ---
> >  kernel/kheaders.c | 19 +++----------------
> >  1 file changed, 3 insertions(+), 16 deletions(-)
> >
> > diff --git a/kernel/kheaders.c b/kernel/kheaders.c
> > index 42163c9e94e557c5043e2ac7987b567f23087ee2..378088b07f46d643736c04b9075f631e0dc2a53d 100644
> > --- a/kernel/kheaders.c
> > +++ b/kernel/kheaders.c
> > @@ -29,25 +29,12 @@ asm (
> >  extern char kernel_headers_data[];
> >  extern char kernel_headers_data_end[];
> >
> > -static ssize_t
> > -ikheaders_read(struct file *file,  struct kobject *kobj,
> > -              struct bin_attribute *bin_attr,
> > -              char *buf, loff_t off, size_t len)
> > -{
> > -       memcpy(buf, &kernel_headers_data[off], len);
> > -       return len;
> > -}
> > -
> > -static struct bin_attribute kheaders_attr __ro_after_init = {
> > -       .attr = {
> > -               .name = "kheaders.tar.xz",
> > -               .mode = 0444,
> > -       },
> > -       .read = &ikheaders_read,
> > -};
> > +static struct bin_attribute kheaders_attr __ro_after_init =
> > +       __BIN_ATTR_SIMPLE_RO(kheaders.tar.xz, 0444);
> >
> >  static int __init ikheaders_init(void)
> >  {
> > +       kheaders_attr.private = kernel_headers_data;
> >         kheaders_attr.size = (kernel_headers_data_end -
> >                               kernel_headers_data);
> >         return sysfs_create_bin_file(kernel_kobj, &kheaders_attr);
> >
> > ---
> > base-commit: 499551201b5f4fd3c0618a3e95e3d0d15ea18f31
> > change-id: 20241215-sysfs-const-bin_attr-kheaders-440887f23892
> >
> > Best regards,
> > --
> > Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
> >
> 
> 
> -- 
> Best Regards
> Masahiro Yamada