Re: [Qemu-devel] [PATCH v3 5/9] xen/9pfs: connect to the frontend

2017-03-17 Thread Stefano Stabellini 
On Fri, 17 Mar 2017, Greg Kurz wrote:
> On Thu, 16 Mar 2017 13:01:54 -0700
> Stefano Stabellini  wrote:
> 
> > Write the limits of the backend to xenstore. Connect to the frontend.
> > Upon connection, allocate the rings according to the protocol
> > specification.
> > 
> > Initialize a QEMUBH to schedule work upon receiving an event channel
> > notification from the frontend.
> > 
> > Signed-off-by: Stefano Stabellini 
> > CC: anthony.per...@citrix.com
> > CC: jgr...@suse.com
> > CC: Aneesh Kumar K.V 
> > CC: Greg Kurz 
> > ---
> >  hw/9pfs/xen-9p-backend.c | 182 
> > ++-
> >  1 file changed, 181 insertions(+), 1 deletion(-)
> > 
> > diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> > index 92bb805..3fd20ff 100644
> > --- a/hw/9pfs/xen-9p-backend.c
> > +++ b/hw/9pfs/xen-9p-backend.c
> > @@ -23,8 +23,39 @@
> >  #define XEN_9PFS_RING_SIZE  XEN_FLEX_RING_SIZE(XEN_9PFS_RING_ORDER)
> >  DEFINE_XEN_FLEX_RING_AND_INTF(xen_9pfs);
> >  
> > +#define VERSIONS "1"
> > +#define MAX_RINGS 8
> > +#define MAX_RING_ORDER 8
> > +
> > +typedef struct Xen9pfsRing {
> > +struct Xen9pfsDev *priv;
> > +
> > +int ref;
> > +xenevtchn_handle   *evtchndev;
> > +int evtchn;
> > +int local_port;
> > +struct xen_9pfs_data_intf *intf;
> > +unsigned char *data;
> > +struct xen_9pfs_data ring;
> > +
> > +QEMUBH *bh;
> > +
> > +/* local copies, so that we can read/write PDU data directly from
> > + * the ring */
> > +RING_IDX out_cons, out_size, in_cons;
> > +bool inprogress;
> > +} Xen9pfsRing;
> > +
> >  typedef struct Xen9pfsDev {
> >  struct XenDevice xendev;  /* must be first */
> > +V9fsState state;
> > +char *path;
> > +char *security_model;
> > +char *tag;
> > +char *id;
> > +
> > +int num_rings;
> > +Xen9pfsRing *rings;
> >  } Xen9pfsDev;
> >  
> >  static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> > @@ -73,22 +104,171 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> >  return 0;
> >  }
> >  
> > +static void xen_9pfs_bh(void *opaque)
> > +{
> > +}
> > +
> > +static void xen_9pfs_evtchn_event(void *opaque)
> > +{
> > +}
> > +
> >  static int xen_9pfs_free(struct XenDevice *xendev)
> >  {
> > -return -1;
> > +int i;
> > +Xen9pfsDev *xen_9pdev = container_of(xendev, Xen9pfsDev, xendev);
> > +
> > +if (xen_9pdev->id != NULL) {
> > +g_free(xen_9pdev->id);
> > +}
> > +if (xen_9pdev->tag != NULL) {
> > +g_free(xen_9pdev->tag);
> > +}
> > +if (xen_9pdev->path != NULL) {
> > +g_free(xen_9pdev->path);
> > +}
> > +if (xen_9pdev->security_model != NULL) {
> > +g_free(xen_9pdev->security_model);
> > +}
> 
> You don't need the if's since g_free(NULL) is legal.

I'll make the changes, thanks


> > +
> > +for (i = 0; i < xen_9pdev->num_rings; i++) {
> > +if (xen_9pdev->rings[i].data != NULL) {
> > +xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> > +xen_9pdev->rings[i].data,
> > +(1 << XEN_9PFS_RING_ORDER));
> > +}
> > +if (xen_9pdev->rings[i].intf != NULL) {
> > +xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> > +xen_9pdev->rings[i].intf,
> > +1);
> > +}
> > +if (xen_9pdev->rings[i].evtchndev > 0) {
> > +
> > qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
> > +NULL, NULL, NULL);
> > +xenevtchn_unbind(xen_9pdev->rings[i].evtchndev,
> > + xen_9pdev->rings[i].local_port);
> > +}
> > +if (xen_9pdev->rings[i].bh != NULL) {
> > +qemu_bh_delete(xen_9pdev->rings[i].bh);
> > +}
> > +}
> > +g_free(xen_9pdev->rings);
> > +return 0;
> >  }
> >  
> >  static int xen_9pfs_connect(struct XenDevice *xendev)
> >  {
> > +int i;
> > +Xen9pfsDev *xen_9pdev = container_of(xendev, Xen9pfsDev, xendev);
> > +V9fsState *s = _9pdev->state;
> > +QemuOpts *fsdev;
> > +
> > +if (xenstore_read_fe_int(_9pdev->xendev, "num-rings",
> > + _9pdev->num_rings) == -1 ||
> > +xen_9pdev->num_rings > MAX_RINGS || xen_9pdev->num_rings < 1) {
> > +return -1;
> > +}
> > +
> > +xen_9pdev->rings = g_malloc0(xen_9pdev->num_rings * 
> > sizeof(Xen9pfsRing));
> > +for (i = 0; i < xen_9pdev->num_rings; i++) {
> > +char *str;
> > +
> > +xen_9pdev->rings[i].priv = xen_9pdev;
> > +xen_9pdev->rings[i].evtchn = -1;
> > +xen_9pdev->rings[i].local_port = -1;
> > +
> > +str = g_strdup_printf("ring-ref%u", i);
> > +if (xenstore_read_fe_int(_9pdev->xendev, str,
> > + _9pdev->rings[i].ref) == -1) {
> > +goto out;
> > +}
> > +

Re: [Qemu-devel] [PATCH v3 5/9] xen/9pfs: connect to the frontend

2017-03-17 Thread Greg Kurz 
On Thu, 16 Mar 2017 13:01:54 -0700
Stefano Stabellini  wrote:

> Write the limits of the backend to xenstore. Connect to the frontend.
> Upon connection, allocate the rings according to the protocol
> specification.
> 
> Initialize a QEMUBH to schedule work upon receiving an event channel
> notification from the frontend.
> 
> Signed-off-by: Stefano Stabellini 
> CC: anthony.per...@citrix.com
> CC: jgr...@suse.com
> CC: Aneesh Kumar K.V 
> CC: Greg Kurz 
> ---
>  hw/9pfs/xen-9p-backend.c | 182 
> ++-
>  1 file changed, 181 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> index 92bb805..3fd20ff 100644
> --- a/hw/9pfs/xen-9p-backend.c
> +++ b/hw/9pfs/xen-9p-backend.c
> @@ -23,8 +23,39 @@
>  #define XEN_9PFS_RING_SIZE  XEN_FLEX_RING_SIZE(XEN_9PFS_RING_ORDER)
>  DEFINE_XEN_FLEX_RING_AND_INTF(xen_9pfs);
>  
> +#define VERSIONS "1"
> +#define MAX_RINGS 8
> +#define MAX_RING_ORDER 8
> +
> +typedef struct Xen9pfsRing {
> +struct Xen9pfsDev *priv;
> +
> +int ref;
> +xenevtchn_handle   *evtchndev;
> +int evtchn;
> +int local_port;
> +struct xen_9pfs_data_intf *intf;
> +unsigned char *data;
> +struct xen_9pfs_data ring;
> +
> +QEMUBH *bh;
> +
> +/* local copies, so that we can read/write PDU data directly from
> + * the ring */
> +RING_IDX out_cons, out_size, in_cons;
> +bool inprogress;
> +} Xen9pfsRing;
> +
>  typedef struct Xen9pfsDev {
>  struct XenDevice xendev;  /* must be first */
> +V9fsState state;
> +char *path;
> +char *security_model;
> +char *tag;
> +char *id;
> +
> +int num_rings;
> +Xen9pfsRing *rings;
>  } Xen9pfsDev;
>  
>  static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> @@ -73,22 +104,171 @@ static int xen_9pfs_init(struct XenDevice *xendev)
>  return 0;
>  }
>  
> +static void xen_9pfs_bh(void *opaque)
> +{
> +}
> +
> +static void xen_9pfs_evtchn_event(void *opaque)
> +{
> +}
> +
>  static int xen_9pfs_free(struct XenDevice *xendev)
>  {
> -return -1;
> +int i;
> +Xen9pfsDev *xen_9pdev = container_of(xendev, Xen9pfsDev, xendev);
> +
> +if (xen_9pdev->id != NULL) {
> +g_free(xen_9pdev->id);
> +}
> +if (xen_9pdev->tag != NULL) {
> +g_free(xen_9pdev->tag);
> +}
> +if (xen_9pdev->path != NULL) {
> +g_free(xen_9pdev->path);
> +}
> +if (xen_9pdev->security_model != NULL) {
> +g_free(xen_9pdev->security_model);
> +}

You don't need the if's since g_free(NULL) is legal.

> +
> +for (i = 0; i < xen_9pdev->num_rings; i++) {
> +if (xen_9pdev->rings[i].data != NULL) {
> +xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> +xen_9pdev->rings[i].data,
> +(1 << XEN_9PFS_RING_ORDER));
> +}
> +if (xen_9pdev->rings[i].intf != NULL) {
> +xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> +xen_9pdev->rings[i].intf,
> +1);
> +}
> +if (xen_9pdev->rings[i].evtchndev > 0) {
> +qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
> +NULL, NULL, NULL);
> +xenevtchn_unbind(xen_9pdev->rings[i].evtchndev,
> + xen_9pdev->rings[i].local_port);
> +}
> +if (xen_9pdev->rings[i].bh != NULL) {
> +qemu_bh_delete(xen_9pdev->rings[i].bh);
> +}
> +}
> +g_free(xen_9pdev->rings);
> +return 0;
>  }
>  
>  static int xen_9pfs_connect(struct XenDevice *xendev)
>  {
> +int i;
> +Xen9pfsDev *xen_9pdev = container_of(xendev, Xen9pfsDev, xendev);
> +V9fsState *s = _9pdev->state;
> +QemuOpts *fsdev;
> +
> +if (xenstore_read_fe_int(_9pdev->xendev, "num-rings",
> + _9pdev->num_rings) == -1 ||
> +xen_9pdev->num_rings > MAX_RINGS || xen_9pdev->num_rings < 1) {
> +return -1;
> +}
> +
> +xen_9pdev->rings = g_malloc0(xen_9pdev->num_rings * sizeof(Xen9pfsRing));
> +for (i = 0; i < xen_9pdev->num_rings; i++) {
> +char *str;
> +
> +xen_9pdev->rings[i].priv = xen_9pdev;
> +xen_9pdev->rings[i].evtchn = -1;
> +xen_9pdev->rings[i].local_port = -1;
> +
> +str = g_strdup_printf("ring-ref%u", i);
> +if (xenstore_read_fe_int(_9pdev->xendev, str,
> + _9pdev->rings[i].ref) == -1) {
> +goto out;
> +}
> +g_free(str);
> +str = g_strdup_printf("event-channel-%u", i);
> +if (xenstore_read_fe_int(_9pdev->xendev, str,
> + _9pdev->rings[i].evtchn) == -1) {
> +goto out;
> +}
> +g_free(str);
> +
> +xen_9pdev->rings[i].intf =  xengnttab_map_grant_ref(
> +

[Qemu-devel] [PATCH v3 5/9] xen/9pfs: connect to the frontend

2017-03-16 Thread Stefano Stabellini 
Write the limits of the backend to xenstore. Connect to the frontend.
Upon connection, allocate the rings according to the protocol
specification.

Initialize a QEMUBH to schedule work upon receiving an event channel
notification from the frontend.

Signed-off-by: Stefano Stabellini 
CC: anthony.per...@citrix.com
CC: jgr...@suse.com
CC: Aneesh Kumar K.V 
CC: Greg Kurz 
---
 hw/9pfs/xen-9p-backend.c | 182 ++-
 1 file changed, 181 insertions(+), 1 deletion(-)

diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
index 92bb805..3fd20ff 100644
--- a/hw/9pfs/xen-9p-backend.c
+++ b/hw/9pfs/xen-9p-backend.c
@@ -23,8 +23,39 @@
 #define XEN_9PFS_RING_SIZE  XEN_FLEX_RING_SIZE(XEN_9PFS_RING_ORDER)
 DEFINE_XEN_FLEX_RING_AND_INTF(xen_9pfs);
 
+#define VERSIONS "1"
+#define MAX_RINGS 8
+#define MAX_RING_ORDER 8
+
+typedef struct Xen9pfsRing {
+struct Xen9pfsDev *priv;
+
+int ref;
+xenevtchn_handle   *evtchndev;
+int evtchn;
+int local_port;
+struct xen_9pfs_data_intf *intf;
+unsigned char *data;
+struct xen_9pfs_data ring;
+
+QEMUBH *bh;
+
+/* local copies, so that we can read/write PDU data directly from
+ * the ring */
+RING_IDX out_cons, out_size, in_cons;
+bool inprogress;
+} Xen9pfsRing;
+
 typedef struct Xen9pfsDev {
 struct XenDevice xendev;  /* must be first */
+V9fsState state;
+char *path;
+char *security_model;
+char *tag;
+char *id;
+
+int num_rings;
+Xen9pfsRing *rings;
 } Xen9pfsDev;
 
 static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
@@ -73,22 +104,171 @@ static int xen_9pfs_init(struct XenDevice *xendev)
 return 0;
 }
 
+static void xen_9pfs_bh(void *opaque)
+{
+}
+
+static void xen_9pfs_evtchn_event(void *opaque)
+{
+}
+
 static int xen_9pfs_free(struct XenDevice *xendev)
 {
-return -1;
+int i;
+Xen9pfsDev *xen_9pdev = container_of(xendev, Xen9pfsDev, xendev);
+
+if (xen_9pdev->id != NULL) {
+g_free(xen_9pdev->id);
+}
+if (xen_9pdev->tag != NULL) {
+g_free(xen_9pdev->tag);
+}
+if (xen_9pdev->path != NULL) {
+g_free(xen_9pdev->path);
+}
+if (xen_9pdev->security_model != NULL) {
+g_free(xen_9pdev->security_model);
+}
+
+for (i = 0; i < xen_9pdev->num_rings; i++) {
+if (xen_9pdev->rings[i].data != NULL) {
+xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
+xen_9pdev->rings[i].data,
+(1 << XEN_9PFS_RING_ORDER));
+}
+if (xen_9pdev->rings[i].intf != NULL) {
+xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
+xen_9pdev->rings[i].intf,
+1);
+}
+if (xen_9pdev->rings[i].evtchndev > 0) {
+qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
+NULL, NULL, NULL);
+xenevtchn_unbind(xen_9pdev->rings[i].evtchndev,
+ xen_9pdev->rings[i].local_port);
+}
+if (xen_9pdev->rings[i].bh != NULL) {
+qemu_bh_delete(xen_9pdev->rings[i].bh);
+}
+}
+g_free(xen_9pdev->rings);
+return 0;
 }
 
 static int xen_9pfs_connect(struct XenDevice *xendev)
 {
+int i;
+Xen9pfsDev *xen_9pdev = container_of(xendev, Xen9pfsDev, xendev);
+V9fsState *s = _9pdev->state;
+QemuOpts *fsdev;
+
+if (xenstore_read_fe_int(_9pdev->xendev, "num-rings",
+ _9pdev->num_rings) == -1 ||
+xen_9pdev->num_rings > MAX_RINGS || xen_9pdev->num_rings < 1) {
+return -1;
+}
+
+xen_9pdev->rings = g_malloc0(xen_9pdev->num_rings * sizeof(Xen9pfsRing));
+for (i = 0; i < xen_9pdev->num_rings; i++) {
+char *str;
+
+xen_9pdev->rings[i].priv = xen_9pdev;
+xen_9pdev->rings[i].evtchn = -1;
+xen_9pdev->rings[i].local_port = -1;
+
+str = g_strdup_printf("ring-ref%u", i);
+if (xenstore_read_fe_int(_9pdev->xendev, str,
+ _9pdev->rings[i].ref) == -1) {
+goto out;
+}
+g_free(str);
+str = g_strdup_printf("event-channel-%u", i);
+if (xenstore_read_fe_int(_9pdev->xendev, str,
+ _9pdev->rings[i].evtchn) == -1) {
+goto out;
+}
+g_free(str);
+
+xen_9pdev->rings[i].intf =  xengnttab_map_grant_ref(
+xen_9pdev->xendev.gnttabdev,
+xen_9pdev->xendev.dom,
+xen_9pdev->rings[i].ref,
+PROT_READ | PROT_WRITE);
+if (!xen_9pdev->rings[i].intf) {
+goto out;
+}
+xen_9pdev->rings[i].data = xengnttab_map_domain_grant_refs(
+xen_9pdev->xendev.gnttabdev,
+(1 << XEN_9PFS_RING_ORDER),
+xen_9pdev->xendev.dom,
+xen_9pdev->rings[i].intf->ref,