[PATCH v4 10/24] xen/arm: compile and run xenbus

[Stefano Stabellini]

On Mon, 17 Sep 2012, Konrad Rzeszutek Wilk wrote:
> On Fri, Sep 14, 2012 at 12:13:12PM +0100, Stefano Stabellini wrote:
> > bind_evtchn_to_irqhandler can legitimately return 0 (irq 0): it is not
> > an error.
> > 
> > If Linux is running as an HVM domain and is running as Dom0, use
> > xenstored_local_init to initialize the xenstore page and event channel.
> > 
> > 
> > Changes in v4:
> > 
> > - do not xs_reset_watches on dom0.
> > 
> > 
> > Changes in v2:
> > 
> > - refactor xenbus_init.
> > 
> > Signed-off-by: Stefano Stabellini <stefano.stabellini at eu.citrix.com>
> 
> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk at oracle.com>
> 
> 
> If you would like I can also carry this in my tree.

OK, let's do that. I'll rebase again on your tree with this patch.


> >  drivers/xen/xenbus/xenbus_comms.c |    2 +-
> >  drivers/xen/xenbus/xenbus_probe.c |   62 +++++++++++++++++++++++++-----------
> >  drivers/xen/xenbus/xenbus_xs.c    |    3 +-
> >  3 files changed, 46 insertions(+), 21 deletions(-)
> > 
> > diff --git a/drivers/xen/xenbus/xenbus_comms.c b/drivers/xen/xenbus/xenbus_comms.c
> > index 52fe7ad..c5aa55c 100644
> > --- a/drivers/xen/xenbus/xenbus_comms.c
> > +++ b/drivers/xen/xenbus/xenbus_comms.c
> > @@ -224,7 +224,7 @@ int xb_init_comms(void)
> >  		int err;
> >  		err = bind_evtchn_to_irqhandler(xen_store_evtchn, wake_waiting,
> >  						0, "xenbus", &xb_waitq);
> > -		if (err <= 0) {
> > +		if (err < 0) {
> >  			printk(KERN_ERR "XENBUS request irq failed %i\n", err);
> >  			return err;
> >  		}
> > diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
> > index b793723..a67ccc0 100644
> > --- a/drivers/xen/xenbus/xenbus_probe.c
> > +++ b/drivers/xen/xenbus/xenbus_probe.c
> > @@ -719,37 +719,61 @@ static int __init xenstored_local_init(void)
> >  	return err;
> >  }
> >  
> > +enum xenstore_init {
> > +	UNKNOWN,
> > +	PV,
> > +	HVM,
> > +	LOCAL,
> > +};
> >  static int __init xenbus_init(void)
> >  {
> >  	int err = 0;
> > +	enum xenstore_init usage = UNKNOWN;
> > +	uint64_t v = 0;
> >  
> >  	if (!xen_domain())
> >  		return -ENODEV;
> >  
> >  	xenbus_ring_ops_init();
> >  
> > -	if (xen_hvm_domain()) {
> > -		uint64_t v = 0;
> > -		err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v);
> > -		if (err)
> > -			goto out_error;
> > -		xen_store_evtchn = (int)v;
> > -		err = hvm_get_parameter(HVM_PARAM_STORE_PFN, &v);
> > -		if (err)
> > -			goto out_error;
> > -		xen_store_mfn = (unsigned long)v;
> > -		xen_store_interface = ioremap(xen_store_mfn << PAGE_SHIFT, PAGE_SIZE);
> > -	} else {
> > -		xen_store_evtchn = xen_start_info->store_evtchn;
> > -		xen_store_mfn = xen_start_info->store_mfn;
> > -		if (xen_store_evtchn)
> > -			xenstored_ready = 1;
> > -		else {
> > +	if (xen_pv_domain())
> > +		usage = PV;
> > +	if (xen_hvm_domain())
> > +		usage = HVM;
> > +	if (xen_hvm_domain() && xen_initial_domain())
> > +		usage = LOCAL;
> > +	if (xen_pv_domain() && !xen_start_info->store_evtchn)
> > +		usage = LOCAL;
> > +	if (xen_pv_domain() && xen_start_info->store_evtchn)
> > +		xenstored_ready = 1;
> > +
> > +	switch (usage) {
> > +		case LOCAL:
> >  			err = xenstored_local_init();
> >  			if (err)
> >  				goto out_error;
> > -		}
> > -		xen_store_interface = mfn_to_virt(xen_store_mfn);
> > +			xen_store_interface = mfn_to_virt(xen_store_mfn);
> > +			break;
> > +		case PV:
> > +			xen_store_evtchn = xen_start_info->store_evtchn;
> > +			xen_store_mfn = xen_start_info->store_mfn;
> > +			xen_store_interface = mfn_to_virt(xen_store_mfn);
> > +			break;
> > +		case HVM:
> > +			err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v);
> > +			if (err)
> > +				goto out_error;
> > +			xen_store_evtchn = (int)v;
> > +			err = hvm_get_parameter(HVM_PARAM_STORE_PFN, &v);
> > +			if (err)
> > +				goto out_error;
> > +			xen_store_mfn = (unsigned long)v;
> > +			xen_store_interface =
> > +				ioremap(xen_store_mfn << PAGE_SHIFT, PAGE_SIZE);
> > +			break;
> > +		default:
> > +			pr_warn("Xenstore state unknown\n");
> > +			break;
> >  	}
> >  
> >  	/* Initialize the interface to xenstore. */
> > diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c
> > index bce15cf..131dec0 100644
> > --- a/drivers/xen/xenbus/xenbus_xs.c
> > +++ b/drivers/xen/xenbus/xenbus_xs.c
> > @@ -44,6 +44,7 @@
> >  #include <linux/rwsem.h>
> >  #include <linux/module.h>
> >  #include <linux/mutex.h>
> > +#include <asm/xen/hypervisor.h>
> >  #include <xen/xenbus.h>
> >  #include <xen/xen.h>
> >  #include "xenbus_comms.h"
> > @@ -622,7 +623,7 @@ static void xs_reset_watches(void)
> >  {
> >  	int err, supported = 0;
> >  
> > -	if (!xen_hvm_domain())
> > +	if (!xen_hvm_domain() || xen_initial_domain())
> >  		return;
> >  
> >  	err = xenbus_scanf(XBT_NIL, "control",
> > -- 
> > 1.7.2.5
>