Willem de Bruijn wrote:
> Akihiko Odaki wrote:
> > Decouple vnet-related functions from tun_struct so that we can reuse
> > them for tap in the future.
> >
> > Signed-off-by: Akihiko Odaki <akihiko.odaki@xxxxxxxxxx>
> > ---
> > drivers/net/tun.c | 53 +++++++++++++++++++++++++++--------------------------
> > 1 file changed, 27 insertions(+), 26 deletions(-)
> >
> > diff --git a/drivers/net/tun.c b/drivers/net/tun.c
> > index ec56ac865848..add09dfdada5 100644
> > --- a/drivers/net/tun.c
> > +++ b/drivers/net/tun.c
> > @@ -298,16 +298,16 @@ static bool tun_napi_frags_enabled(const struct tun_file *tfile)
> > return tfile->napi_frags_enabled;
> > }
> >
> > -static inline bool tun_legacy_is_little_endian(struct tun_struct *tun)
> > +static inline bool tun_legacy_is_little_endian(unsigned int flags)
> > {
> > return !(IS_ENABLED(CONFIG_TUN_VNET_CROSS_LE) &&
> > - (tun->flags & TUN_VNET_BE)) &&
> > + (flags & TUN_VNET_BE)) &&
> > virtio_legacy_is_little_endian();
> > }
> >
> > -static long tun_get_vnet_be(struct tun_struct *tun, int __user *argp)
> > +static long tun_get_vnet_be(unsigned int flags, int __user *argp)
> > {
> > - int be = !!(tun->flags & TUN_VNET_BE);
> > + int be = !!(flags & TUN_VNET_BE);
> >
> > if (!IS_ENABLED(CONFIG_TUN_VNET_CROSS_LE))
> > return -EINVAL;
> > @@ -318,7 +318,7 @@ static long tun_get_vnet_be(struct tun_struct *tun, int __user *argp)
> > return 0;
> > }
> >
> > -static long tun_set_vnet_be(struct tun_struct *tun, int __user *argp)
> > +static long tun_set_vnet_be(unsigned int *flags, int __user *argp)
> > {
> > int be;
> >
> > @@ -329,27 +329,26 @@ static long tun_set_vnet_be(struct tun_struct *tun, int __user *argp)
> > return -EFAULT;
> >
> > if (be)
> > - tun->flags |= TUN_VNET_BE;
> > + *flags |= TUN_VNET_BE;
> > else
> > - tun->flags &= ~TUN_VNET_BE;
> > + *flags &= ~TUN_VNET_BE;
> >
> > return 0;
> > }
> >
> > -static inline bool tun_is_little_endian(struct tun_struct *tun)
> > +static inline bool tun_is_little_endian(unsigned int flags)
> > {
> > - return tun->flags & TUN_VNET_LE ||
> > - tun_legacy_is_little_endian(tun);
> > + return flags & TUN_VNET_LE || tun_legacy_is_little_endian(flags);
> > }
> >
> > -static inline u16 tun16_to_cpu(struct tun_struct *tun, __virtio16 val)
> > +static inline u16 tun16_to_cpu(unsigned int flags, __virtio16 val)
> > {
> > - return __virtio16_to_cpu(tun_is_little_endian(tun), val);
> > + return __virtio16_to_cpu(tun_is_little_endian(flags), val);
> > }
> >
> > -static inline __virtio16 cpu_to_tun16(struct tun_struct *tun, u16 val)
> > +static inline __virtio16 cpu_to_tun16(unsigned int flags, u16 val)
> > {
> > - return __cpu_to_virtio16(tun_is_little_endian(tun), val);
> > + return __cpu_to_virtio16(tun_is_little_endian(flags), val);
> > }
> >
> > static inline u32 tun_hashfn(u32 rxhash)
> > @@ -1764,6 +1763,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
> >
> > if (tun->flags & IFF_VNET_HDR) {
> > int vnet_hdr_sz = READ_ONCE(tun->vnet_hdr_sz);
> > + int flags = tun->flags;
>
> Here and elsewhere: instead of passing around and repeatedly parsing
> flags, have a variable is_little_endian (or is_le)?
I guess this will not work everywhere, because endianness is not a
boolean flag.. Code checks both TUN_VNET_LE and TUN_VNET_BE.
