Re: [v8][PATCH 05/17] tools/libxc: introduce hypercall for xc_reserved_device_memory_map

["Chen, Tiejun" <tiejun.chen@intel.com>]

On 2014/12/3 3:50, Konrad Rzeszutek Wilk wrote:
> On Mon, Dec 01, 2014 at 05:24:23PM +0800, Tiejun Chen wrote:
>> We will introduce that hypercall xc_reserved_device_memory_map
>> approach to libxc.
>>
>> Signed-off-by: Tiejun Chen <tiejun.chen@intel.com>
>> ---
>>   tools/libxc/include/xenctrl.h |  5 +++++
>>   tools/libxc/xc_domain.c       | 30 ++++++++++++++++++++++++++++++
>>   2 files changed, 35 insertions(+)
>>
>> diff --git a/tools/libxc/include/xenctrl.h b/tools/libxc/include/xenctrl.h
>> index 84012fe..a3aeac3 100644
>> --- a/tools/libxc/include/xenctrl.h
>> +++ b/tools/libxc/include/xenctrl.h
>> @@ -1294,6 +1294,11 @@ int xc_domain_set_memory_map(xc_interface *xch,
>>   int xc_get_machine_memory_map(xc_interface *xch,
>>                                 struct e820entry entries[],
>>                                 uint32_t max_entries);
>> +
>> +int xc_reserved_device_memory_map(xc_interface *xch,
>> +                                  uint32_t dom,
>> +                                  struct xen_reserved_device_memory entries[],
>> +                                  uint32_t *max_entries);
>>   #endif
>>   int xc_domain_set_time_offset(xc_interface *xch,
>>                                 uint32_t domid,
>> diff --git a/tools/libxc/xc_domain.c b/tools/libxc/xc_domain.c
>> index 7fd43e9..09fd988 100644
>> --- a/tools/libxc/xc_domain.c
>> +++ b/tools/libxc/xc_domain.c
>> @@ -679,6 +679,36 @@ int xc_domain_set_memory_map(xc_interface *xch,
>>
>>       return rc;
>>   }
>> +
>> +int xc_reserved_device_memory_map(xc_interface *xch,
>> +                                  uint32_t domid,
>> +                                  struct xen_reserved_device_memory entries[],
>> +                                  uint32_t *max_entries)
>> +{
>> +    int rc;
>> +    struct xen_reserved_device_memory_map xrdmmap = {
>> +        .domid = domid,
>> +        .nr_entries = *max_entries
>> +    };
>> +    DECLARE_HYPERCALL_BOUNCE(entries,
>> +                             sizeof(struct xen_reserved_device_memory) *
>> +                             *max_entries, XC_HYPERCALL_BUFFER_BOUNCE_OUT);
>> +
>> +    if ( xc_hypercall_bounce_pre(xch, entries) )
>> +        return -1;
>> +
>> +    set_xen_guest_handle(xrdmmap.buffer, entries);
>> +
>> +    rc = do_memory_op(xch, XENMEM_reserved_device_memory_map,
>> +                      &xrdmmap, sizeof(xrdmmap));
>> +
>> +    xc_hypercall_bounce_post(xch, entries);
>> +
>> +    *max_entries = xrdmmap.nr_entries;
>> +
>
> I would bake the -EAGAIN support in here to loop here.
>
> See how the xc_domain_destroy does it.

Do you mean this change?

@@ -699,8 +699,10 @@ int xc_reserved_device_memory_map(xc_interface *xch,

      set_xen_guest_handle(xrdmmap.buffer, entries);

-    rc = do_memory_op(xch, XENMEM_reserved_device_memory_map,
-                      &xrdmmap, sizeof(xrdmmap));
+    do {
+        rc = do_memory_op(xch, XENMEM_reserved_device_memory_map,
+                          &xrdmmap, sizeof(xrdmmap));
+    } while ( rc && (errno == EAGAIN) );

      xc_hypercall_bounce_post(xch, entries);

Thanks
Tiejun

>> +    return rc ? rc : xrdmmap.nr_entries;
>> +}
>> +
>>   int xc_get_machine_memory_map(xc_interface *xch,
>>                                 struct e820entry entries[],
>>                                 uint32_t max_entries)
>> --
>> 1.9.1
>>
>