Re: [Qemu-devel] [PATCH 2/4] 9pfs: introduce transport specific callbacks

[Greg Kurz <groug@kaod.org>]

On Thu, 24 Nov 2016 09:31:52 +0100
Greg Kurz <groug@kaod.org> wrote:

> On Mon, 21 Nov 2016 13:39:30 -0800
> Stefano Stabellini <sstabellini@kernel.org> wrote:
> 
> > Don't call virtio functions from 9pfs generic code, use generic function
> > callbacks instead.
> > 
> > Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
> > ---  
> 
> Just a couple of indentation and line over 80 characters nits. I'll fix them
> before pushing to 9p-next.
> 
> Reviewed-by: Greg Kurz <groug@kaod.org>
> 

Hmm... second thought...

> >  hw/9pfs/9p.c               |  8 ++++----
> >  hw/9pfs/9p.h               | 18 ++++++++++++++++++
> >  hw/9pfs/virtio-9p-device.c | 18 ++++++++++++++----
> >  hw/9pfs/virtio-9p.h        |  9 ---------
> >  4 files changed, 36 insertions(+), 17 deletions(-)
> > 
> > diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
> > index 05e950f..5a20a13 100644
> > --- a/hw/9pfs/9p.c
> > +++ b/hw/9pfs/9p.c
> > @@ -47,7 +47,7 @@ ssize_t pdu_marshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...)
> >      va_list ap;
> >  
> >      va_start(ap, fmt);
> > -    ret = virtio_pdu_vmarshal(pdu, offset, fmt, ap);
> > +    ret = pdu->s->transport->pdu_vmarshal(pdu, offset, fmt, ap);
> >      va_end(ap);
> >  
> >      return ret;
> > @@ -59,7 +59,7 @@ ssize_t pdu_unmarshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...)
> >      va_list ap;
> >  
> >      va_start(ap, fmt);
> > -    ret = virtio_pdu_vunmarshal(pdu, offset, fmt, ap);
> > +    ret = pdu->s->transport->pdu_vunmarshal(pdu, offset, fmt, ap);
> >      va_end(ap);
> >  
> >      return ret;
> > @@ -67,7 +67,7 @@ ssize_t pdu_unmarshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...)
> >  
> >  static void pdu_push_and_notify(V9fsPDU *pdu)
> >  {
> > -    virtio_9p_push_and_notify(pdu);
> > +    pdu->s->transport->push_and_notify(pdu);
> >  }
> >  
> >  static int omode_to_uflags(int8_t mode)
> > @@ -1751,7 +1751,7 @@ static void v9fs_init_qiov_from_pdu(QEMUIOVector *qiov, V9fsPDU *pdu,
> >      struct iovec *iov;
> >      unsigned int niov;
> >  
> > -    virtio_init_iov_from_pdu(pdu, &iov, &niov, is_write);
> > +    pdu->s->transport->init_iov_from_pdu(pdu, &iov, &niov, is_write);
> >  
> >      qemu_iovec_init_external(&elem, iov, niov);
> >      qemu_iovec_init(qiov, niov);
> > diff --git a/hw/9pfs/9p.h b/hw/9pfs/9p.h
> > index 07cee01..ab398d0 100644
> > --- a/hw/9pfs/9p.h
> > +++ b/hw/9pfs/9p.h
> > @@ -230,6 +230,7 @@ typedef struct V9fsState
> >      enum p9_proto_version proto_version;
> >      int32_t msize;
> >      V9fsPDU pdus[MAX_REQ];
> > +    struct V9fsTransport *transport;
> >      /*
> >       * lock ensuring atomic path update
> >       * on rename.
> > @@ -343,4 +344,21 @@ void pdu_free(V9fsPDU *pdu);
> >  void pdu_submit(V9fsPDU *pdu);
> >  void v9fs_reset(V9fsState *s);
> >  
> > +struct V9fsTransport {
> > +    ssize_t     (*pdu_vmarshal)(V9fsPDU *pdu, size_t offset, const char *fmt, va_list ap);  
> 
> over 80 characters
> 
> > +    ssize_t     (*pdu_vunmarshal)(V9fsPDU *pdu, size_t offset, const char *fmt, va_list ap);  
> 
> ditto
> 
> > +    void        (*init_iov_from_pdu)(V9fsPDU *pdu, struct iovec **piov,
> > +                              unsigned int *pniov, bool is_write);  
> 
> indent
> 
> > +    void        (*push_and_notify)(V9fsPDU *pdu);
> > +};
> > +
> > +static inline int v9fs_register_transport(V9fsState *s, struct V9fsTransport *t)
> > +{
> > +    if (s->transport) {
> > +        return -EINVAL;
> > +    }
> > +    s->transport = t;
> > +    return 0;
> > +}
> > +
> >  #endif
> > diff --git a/hw/9pfs/virtio-9p-device.c b/hw/9pfs/virtio-9p-device.c
> > index 1782e4a..e1a37a4 100644
> > --- a/hw/9pfs/virtio-9p-device.c
> > +++ b/hw/9pfs/virtio-9p-device.c
> > @@ -20,7 +20,9 @@
> >  #include "hw/virtio/virtio-access.h"
> >  #include "qemu/iov.h"
> >  
> > -void virtio_9p_push_and_notify(V9fsPDU *pdu)
> > +static struct V9fsTransport virtio_9p_transport;

... shouldn't this be const ?

> > +
> > +static void virtio_9p_push_and_notify(V9fsPDU *pdu)
> >  {
> >      V9fsState *s = pdu->s;
> >      V9fsVirtioState *v = container_of(s, V9fsVirtioState, state);
> > @@ -126,6 +128,7 @@ static void virtio_9p_device_realize(DeviceState *dev, Error **errp)
> >      v->config_size = sizeof(struct virtio_9p_config) + strlen(s->fsconf.tag);
> >      virtio_init(vdev, "virtio-9p", VIRTIO_ID_9P, v->config_size);
> >      v->vq = virtio_add_queue(vdev, MAX_REQ, handle_9p_output);
> > +    v9fs_register_transport(s, &virtio_9p_transport);
> >  
> >  out:
> >      return;
> > @@ -148,7 +151,7 @@ static void virtio_9p_reset(VirtIODevice *vdev)
> >      v9fs_reset(&v->state);
> >  }
> >  
> > -ssize_t virtio_pdu_vmarshal(V9fsPDU *pdu, size_t offset,
> > +static ssize_t virtio_pdu_vmarshal(V9fsPDU *pdu, size_t offset,
> >                              const char *fmt, va_list ap)  
> 
> indent
> 
> >  {
> >      V9fsState *s = pdu->s;
> > @@ -158,7 +161,7 @@ ssize_t virtio_pdu_vmarshal(V9fsPDU *pdu, size_t offset,
> >      return v9fs_iov_vmarshal(elem->in_sg, elem->in_num, offset, 1, fmt, ap);
> >  }
> >  
> > -ssize_t virtio_pdu_vunmarshal(V9fsPDU *pdu, size_t offset,
> > +static ssize_t virtio_pdu_vunmarshal(V9fsPDU *pdu, size_t offset,
> >                                const char *fmt, va_list ap)  
> 
> indent
> 
> >  {
> >      V9fsState *s = pdu->s;
> > @@ -168,7 +171,7 @@ ssize_t virtio_pdu_vunmarshal(V9fsPDU *pdu, size_t offset,
> >      return v9fs_iov_vunmarshal(elem->out_sg, elem->out_num, offset, 1, fmt, ap);
> >  }
> >  
> > -void virtio_init_iov_from_pdu(V9fsPDU *pdu, struct iovec **piov,
> > +static void virtio_init_iov_from_pdu(V9fsPDU *pdu, struct iovec **piov,
> >                                unsigned int *pniov, bool is_write)  
> 
> indent
> 
> >  {
> >      V9fsState *s = pdu->s;
> > @@ -184,6 +187,13 @@ void virtio_init_iov_from_pdu(V9fsPDU *pdu, struct iovec **piov,
> >      }
> >  }
> >  
> > +static struct V9fsTransport virtio_9p_transport = {
> > +    .pdu_vmarshal = virtio_pdu_vmarshal,
> > +    .pdu_vunmarshal = virtio_pdu_vunmarshal,
> > +    .init_iov_from_pdu = virtio_init_iov_from_pdu,
> > +    .push_and_notify = virtio_9p_push_and_notify,
> > +};
> > +
> >  /* virtio-9p device */
> >  
> >  static const VMStateDescription vmstate_virtio_9p = {
> > diff --git a/hw/9pfs/virtio-9p.h b/hw/9pfs/virtio-9p.h
> > index 52c4b9d..e763da2c 100644
> > --- a/hw/9pfs/virtio-9p.h
> > +++ b/hw/9pfs/virtio-9p.h
> > @@ -14,15 +14,6 @@ typedef struct V9fsVirtioState
> >      V9fsState state;
> >  } V9fsVirtioState;
> >  
> > -void virtio_9p_push_and_notify(V9fsPDU *pdu);
> > -
> > -ssize_t virtio_pdu_vmarshal(V9fsPDU *pdu, size_t offset,
> > -                            const char *fmt, va_list ap);
> > -ssize_t virtio_pdu_vunmarshal(V9fsPDU *pdu, size_t offset,
> > -                              const char *fmt, va_list ap);
> > -void virtio_init_iov_from_pdu(V9fsPDU *pdu, struct iovec **piov,
> > -                              unsigned int *pniov, bool is_write);
> > -
> >  #define TYPE_VIRTIO_9P "virtio-9p-device"
> >  #define VIRTIO_9P(obj) \
> >          OBJECT_CHECK(V9fsVirtioState, (obj), TYPE_VIRTIO_9P)  
> 
>